stc annual report 2009

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Sensible Things that Communicate Annual Report 2009

Diarienummer: MIUN2010/559Cover picture photografer: Tina Stafrén Annual Report 2009 - Contact person: Program leader Mattias O’Nils

Table of contents1. Introduction 4

2. Research objectives 5

3. Illustration of the integration of research 7 3.1 Failure warning system 7

4. Summary of research results 10 4.1 System on FPGA and Vision 10 4.2 Sensor Network Security 14 4.3 Wireless Sensor Systems 15 4.3.1 Complex Wireless sensors 15 4.3.2 Environmental monitoring 18 4.3.3 Environmental monitoring system 19 4.3.4 Initiated Co-operations 22 4.4 Sensor Technologies 23 4.5 Sensor-based Services 26

5. Awards in 2009 27 5.1 The Sundsvall 42 scholarship 27 5.2 STC winner in Swedish Embedded Award 2009 28

6. PhD examinations during 2009 29 6.1 Dr. Najeem Lawal 29 6.2 Dr. Claes Mattsson 30

7. New staff and promotions 32 7.1 New PhD students within STC and supporting projects 35

8. Publications 2009 40

9. STC@MIUN research projects 44

Sensible Things that Communicate The STC@MIUN Research program

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1 IntroductionSTC@MIUN has during five years developed into a centre for innovative sensor based sys-tems and services with wide source of funding. During 2009, the 11th professor and 13 new PhD students joined the STC@MIUN environment, which means that over 70 researchers work to develop new technology in the areas of sensor technology, wireless sensor systems, system on FPGA and vision, sensor network security and sensor-based services. These re-search programs have a joint goal: to develop sensor based system and services within the areas of Industrial IT, Mobile services and Green awareness.

Figure 1. Research programs within STC@MIUN and the focused application areas.

The research centre STC@MIUN were during 2009 identified as one of four prioritized areas at Mid Sweden University that has started to implement a common research profile. STC@MIUN is also successfully integrated with education in both computer science and electronics in Mid Sweden University. Both master’s programs in computer science and electronics tar-gets a curriculum closely related to the research within STC@MIUN and its partner compa-nies. During 2009 the success of these programs is shown through two student works that has been awarded. Cheng Peng has won the Swedish Embedded Award with a Stator free RPM-sensor and Stefan Forsström were awarded a scholarship for best student work at the Sunds-vall42 conference for the master’s thesis “Fast Location - Scoped Context Dissemination”.

Applications Areas

Industrial IT

Sensor Technology

Wireless Sensor Systems

System on FPGA and Vision

Sensor-Based Services

Sensor Network Security

Mobile Services

Green Awareness

Technologies

Sensible Things that Communicate The STC@MIUN Research programSensible Things that Communicate The STC@MIUN Research program

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2 Research objectivesThe objective of STC@MIUN is to develop knowledge and technology to supportdistributed sensing in industrial, personal and environmental applications. Distributed sensing tech-nology will enable advanced digital services such as, for example, remote presence or high precision visibility in industrial supply chains, as illustrated in Fig 2 below. The distributed sensing demands stable intelligent sensor network solutions operating at low power levels, utilizing energy harvesting or other smart power solutions. The focus of STC@MIUN is on particular sensor network technologies of relevance for our industrial partners and utilizing advantages associated with both the research environment and competence at Mid Sweden University. The targeted research field is large and STC@MIUN will not be able to cover all aspects of the field.

Figure 2. Illustration of the evolution of telecommunication towards true remote presence services.

Our main focus is on key technology areas such as:

• real-time video processing• secure and power efficient routing / networking• low-power collaborative sensing• energy harvesting• low-cost radiation sensor solutions• printed electronics• mobile services based on sensor data.

Reading Hearing Seeing MDNMC BeingSensing

Communication:Human - Human

Communication:Human - NatureHuman - MachineMachine - Machine

Real-time virtual face-to-facecommunication and interaction.

Telegraph TelephoneRadio broadcast

TV Mobile, InternetSatellite, Fiber-optic

WSN(WSAN, RFID)

3D virtual vision


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Figure 3. Time evolution of objectives for the STC@MIUN research program

Initially, our resources were concentrated on the development of key technologies of rele-van-ce for different industrial partners. The next step in the project is to target the development of more system oriented demonstrators where the developed technologies will be utilized to show new functionalities and service solutions. Our ambition is to demonstrate both new technological solutions and new service concepts of general industrial interest. The evolution of the research objectives within STC@MIUN are presented in Fig. 3 and an example of the integration of research efforts is given in Section 3.

Development of technology plattforms

Development of concept demonstrators

Further development of technology platforms

Demonstration of service concepts

Start End


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3. Illustration of the integration of researchThe reference system for STC@MIUN can be described as a network of connected sensing nodes. The sensing nodes use different types of detectors, different types of intelligence and different types of communication. The nodes range from dispensable sensor nodes based on printed electronics to highly complex camera based sensors, illustrated in Fig.4

Figure 4. Distributed electronic system used as the reference system for the research in the profile.

3.1 Failure warning system A failure warning system for hydraulic motors is a god example of a project within STC@MIUN that illustrates how the different research programs integrate the competence to realize the vision of the reference system in Fig. 4. The failure of hydraulic motors can be predicted through detection of magnetic particles in the oil. Today this can be monitored manually, which means that the possibility to detect a failure is expensive and hard. If this could be measured automatically and remotely, it would enable a whole new business for the manufacture of the hydraulic motors (Hägglund Drives).

Figure 5. Hägglund Drives hydraulic motors and the possible geographical mobile service for tracking failure.

Access network node

Communication access point

Surveillance node

Telemedicine node

Visualization node Multimedia terminal

Dispensable communication terminal

Arbitrary STC


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The detection of magnetic particles can be done with electrical methods and optical methods. After analysis work by the sensor technology and vision research programs, a decision to use optical methods were made. The first prototype of an optical measurement node and a cap-tured image from the system is shown in Fig. 6.

Figure 6. Optical measurement setup and images captured in this.

Implementing the system under the constraints that the system should be wireless regar-ding both power and communication to avoid installation problems. Additional, the system should have a battery lifetime that is equivalent to the system it measures. Involving the Wireless sensor system research program an initial wireless sensing node has been evaluated. The common wireless sensor platform, Sentio 32, together with an industrial camera chip where used in the feasibility study. The result from this initial study show that if it is enough to measure three times per day, a system life time of 5.5 years can be achived.

Figure 7. Evaluation of system life time using standard batteries for the Sentio 32 based optical measure-ment setup for characterizing magnetic particles.


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In the final installation of this system, a global and geographical service needs to be develo-ped based on the theory and methods that is developed within the sensor-based services re-search program. Since the developed remote sensing service can be developed to a business, other aspect that needs to be considered is the reliability and security of the measured data. These aspects are investigated within the Sensor network security research program.

Figure 8. Interaction of competences in a common research problem.

The early failure warning system is a good example of how all parts of STC@MIUN interacts to investigate and develop a specific scenario, as shown in Fig. 8. It is also a good example of the targeted system and services for the Industrial IT applications within STC@MIUN. How-ever, this broad cooperation only applies on a few research projects, other focus on one or a few aspects of the STC@MIUN research areas.

Early failure warning system Specific challenges

General aspects of mobile sensor system

Electrical methods

Sensor Technology

Sentio32 platform and lifetime analysis

Wireless Sensor Systems

Optical methods and real-time implementation of

image processing

System on FPGA and Vision

Sensor Network Security

Mobile services

Sensor-based Services

Sensor network security Network Security


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4 Summary of research results4.1 System on FPGA and VisionThe mission statement for the STC Systems on FPGA and Vision was initially defined as being to discover when, where and how system integration on FPGA is a good implementa-tion alternative for industrial and automotive embedded systems. Points of investigation were with regards to developing applications for the technology, investigating cost issues and optimizing low power consumption for FPGA based systems. This year’s work includes a number of activities on embedded machine vision applications. New activities in the area of IP-core based design techniques including portability and lifetime aspects are defined, scheduled and initiated during this year. The results for 2009 can be summarized as follows:

Automatic design methods for optimized implementation of real-time video processing systems: We have previously developed a memory synthesis design flow for FPGA implementation of real-time video processing. This synthesis is based on methods to optimize the memory architecture for area and power and for a selected FPGA architecture. During 2008 Dr. Najeem Lawal had his dissertation from this work. During 2009, one scienti-fic journal paper was in progress and was updated according to editor’s recommendations.

Investigation of specific challenges in real-time video processing systems: An FPGA based multi-channel analogue video-display computer was demonstrated during previous years and an extension with digital Ethernet-based video streams was partly added. During 2009, a master thesis work was presented on this topic indicating that it will be possible to reach real-time performance for the demultiplexing of up to four input Ethernet video streams. Our partner CC Systems AB wanted a change of the topic for their activities in STC and we therefore defined a new area called IP design for Sensor- and Actuator Nodes.

IP design for Sensor- and Actuator Networking Nodes: In corporation with CC Sys-tems AB, new research activities were defined and scheduled for autumn 2009 until the end of 2011. These activities address the research questions on how the introduction of an FPGA platform will affect the product lifetimes, how can IP-design techniques be applied to in-crease design reuse and to what degree is portability over FPGA- vendors, families and devi-ces possible? Figure 1 depicts the envisioned prototype sensor- and actuator node connected by CAN through an USB-CAN converter to personal computer.

Even though video applications are no longer the main target for our research with CC Sys-tems, some general aspects on IP design techniques were developed with an MJPEG decoder as demonstration application. During 2009, an MJPEG decoder project was freely downloa-ded from OpenCores and analysed with respect to aspects on management of interfaces. This work resulted in the definition of a methodology having focus on separating communi-cation from computation and managing the update and reuse of interfaces for an IP-core. A scientific publication was submitted to a conference.


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Analysis and development of embedded machine vision applications: A project in cooperation with STC Sensor Solutions is aimed at the detection and characterization of mag-netic particles in hydraulic fluid. This is an industrial application of video processing at low sampling rates in the temporal domain. Reaching low energy for a battery powered wireless solution is a clear research challenge. Experimental work on modelling behaviour and en-ergy consumption for this smart camera application was carried out during 2009. From the master thesis that Mohammad Anzar Alam presented, we can conclude that battery life times of about six years can be expected if the camera is powered with four 2,6 Ah batteries. These results are approximated for a micro controller based smart camera including also LED flash light and RF communication and at a sampling rate of about 45 minutes. An experimental optical measurement cell having a hydraulic system of circulating oil, polluted with particles was built and delivered from our partner company Hägglunds. See Figure 2. Future activities include fine tuning of smart camera algorithms for that measurement cell.

Figure 1. Experimental platform for sensor networking nodes.

Figure 2. Measurement cell for hydralic oil. On the right down corner shows one acquired image.


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We have in addition two externally funded projects in embedded machine vision. One of the projects investigates real-time measurements of surface topography. An experimental topo-logy measurement system for laboratory environments was set up to work with good results during 2008. During 2009, an online measurement system was set up to work at Iggesund paper mill running a prototype paper line at 800 m/minute. See Figure 3. The results look promising so far. Online topology measurements will enable our partners to improve quality and the efficiency of use of raw material at paper mills.

The second externally founded project - OptiPos, is focused on front-end image processing of a 6DOF position- and orientation measurement system. During 2009, a scientific article was published at an IEEE conference in Romania. This project is now also enforced with a new PhD student - Waheed Malik, who is going to work with hardware architectures for smart cameras. A second paper addressing position measurements at subpixel precision was submitted and accepted for a conference in Rome. A prototype camera is now also set up to primarily run 2D Centre Of Gravity calculations at real time (640 by 480 frames at 60 Hz). An InfraRed flashing light was developed as a bachelor thesis work and made to interface with the mentioned camera prototype. See Figure 4.

Figure 4. FPGA based smart camera with megapixel optics and a flash light for infrared wavelengths.

Figure 3. Online measurement of paper topography.


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PrintDreams Ltd is a partner company working with a handheld printer which is their main product under development. Experiments with a similar technique for optical navigation over a surface in 3DOF are carried out within OptiPos. For this purpose, a small experimental vehicle carrying a smart camera system was built. See Figure 5. The image processing app-lication for navigation has been successfully modelled in Matlab. We have plans to use high level synthesis tools capable of reading this Matlab model and use it for hardware implemen-tation on FPGA. Ongoing work is related to debugging and verification at different abstrac-tion levels. We have good hopes to have a running prototype ready during 2010.

Figure 5. Prototype vehicle equipped with cameras and illumination for optical navigation.


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4.2 Sensor Network SecurityThe overall goals for the network solution part of the profile are to discover efficient (lower power) and secure sensor data collection for applications such as environment monitoring, surveillance and network traffic monitoring. Our results for 2009 can be summarized as follows:

Bottleneck Zone analysis in energy-constrained wireless sensor networks: We found the traffic load distribution over the deployed nodes as a function of their distances from the sink in the even-distributed large-scale and dense sensor networks. It was shown that the traffic load over a node increases when the nodes get closer to the sink, and a traffic load blowout is expected in the proximity of the sink.

Privacy and ID Management for sensor based application in Cloud Computing: We proposed a privacy preserved framework which can be utilized by value-added context-aware service cloud. Context data and related services access privileges are determined by context-aware role-based access control (CRAC) extended from role-based access control (RAC). Privacy preserved context service protocol (PPCS) is designed to protect user privacy from exposed context information. Additionally, user network and information diffusion is combined to evaluate the privacy protection effect.

We analysed the danger of sharing clear text ID profiles between different clouds. To solve this problem, a privacy preserved ID profile utilizing protocol PPID protocol is proposed. In PPID, ID and service are divided, so third party service cloud and service provider cloud can utilize user information without sacrifice user’s ID privacy. And, for cloud with simple privileges levels, this protocol can be extended to IDA protocol to provide wider privacy preserved ID services.


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4.3 Wireless Sensor SystemsOur overall objective is to increase the understanding of the problems of integrating embed-ded wireless sensors in the physical environment governed by the applications. The work in Wireless Systems focuses on two areas – complex wireless sensor nodes and technologies for environmental monitoring.

The objective of the work in complex sensor nodes is to find hardware implementation stra-tegies for sensors requiring high computational capabilities for in-sensor signal processing We focus on measuring parameters of importance for rotating machineries.

In environmental monitoring we are addressing the problems of self-powered sensors opera-ting in energy-starved environments.

During 2009 we have initiated collaborations with partners with application-specific know-ledge and interest in in situ measurements based on wireless sensors.

4.3.1 Complex Wireless SensorsWireless RPM Sensor: We have proposed a technique for measuring rotation speed. It addresses the problem of reliability of RPM sensing where the most critical component of conventional techniques, that is the bearing, can be omitted with our technique.A statistical simulation model has been developed and simulations have been used to eva-luate the technique. We can for example show that its precision is competitive in relation to existing techniques for high RPMs.


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A manuscript targeting a journal paper is currently in the review process and provides a sensitivity analysis including parameter for the individual sensing elements and parameters for the sensor system. (Stator-free RPM Sensor Using Accelerometers)

Another manuscript for journal publication is also in the review process (Design and Imple-mentation of Stator-free RPM Sensor Based on MEMS Accelerometers). This paper describes the implementation, calibration, and characterization of the RPM sensor. A prototype of the RPM sensor is shown below.

The sensor won the Swedish Embedded Award 2009 in the category Micro/Nano.

3D Vibration Sensor: Vibration analysis is used in condition monitoring for a wide range of applications. The analysis is made in the frequency domain and for detection of abnorma-lities related to bearing wear-out a sequence of frequency spectrums is needed for the vibra-tion analysis. Typically, a sample rate of hundreds of samples per second is needed where every sample is a spectrum of 1024 – 8192 points. Beside high computational capacity, also an efficient memory system is needed for in-sensor analysis. The analysis has to be performed in the sensor because of the limited bandwidth of the wireless communication.

We are aiming at developing an energy-efficient HW/SW architecture for such sensor. Cur-rently we have a working prototype capable of producing a 1024-point FFT in 5ms. The wireless 3D vibration sensor has a signal bandwidth of 22kHz and includes the RPM sensor previously described, a microSD card (8GByte), and a IEEE802.15.4 radio interface. The size is 50 x 31 x 12 mm3 including battery, see picture on the next side.


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Future work will investigate other architectures and implementation strategies to explore low-energy wireless vibration sensors.

Wireless 3D Motion Sensor: We have developed a generic wireless 3D Motion sensor unit that enables us to do initial motion analysis of both mechanical and bio-mechanical systems. It can be seen as a tool in the initial studies. Our sensor, that we call SCube, measures linear acceleration, angular speed, and orientation (using magnetometer) in all three dimensions. It is designed to be used with our wireless platform SENTIO32. The SCube is a compact solu-tion of size 50 x 31 x 12 mm (18.6 cm3). The power supply comes from a battery mounted between the sensor board and the SENTIO32. A picture of the complete unit is shown below.


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4.3.2 Environmental monitoringBasic Low-Energy Protocol: It is well known that highly synchronized TDMA-based protocols enables efficient usage of duty cycling to obtain low energy consumption of the wireless sensor nodes. The problem with this approach is that synchronism must be maintai-ned throughout the network. The crystals have a relatively high temperature coefficient. For environmental monitoring applications, it cannot be assumed that the variations in tempera-ture are the same for all nodes in the network. Due to the large distances between the nodes, different locations will expose some to the sun where others are in the shade. Large differen-ces in temperature variations must therefore be expected. We propose an adaptive synchro-nization scheme with local temperature compensation. We have shown that this approach has lower energy overhead than if relaxation of the synchronization requirements are used. At this stage we limit ourselves to star topology networks. The graphs below shows measurement results of what we can achieve when it comes to reduction of the time deviations between different nodes experiencing different temperature transients (left graphs: non-compensated, right graphs: compensated).

With the temperature compensation method implemented, stability in the synchronization protocol could be widely ensured under varying temperature conditions and synchroniza-tion accuracy was kept in the same order as under constant temperature conditions.


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Energy Harvesting: In this work we address the feasibility of battery-less operation of wireless sensor nodes using solar energy harvesting at locations where the amount of solar radiation is severely limited and the seasonal variation is large. We present two circuit ar-chitectures optimized for low energy leakage and evaluate their performance based on data gathered in a deployment during winter in Sundsvall, Sweden. We show that both architec-

tures allow operation of sensor nodes even in the darkest period of the year. The daily and seasonal variations at the test site in Sundsvall are shown below.

Because environmental monitoring applications usually demand very long lifetimes of years or tens of years without human interaction, rechargeable batteries as the energy storage tech-nology is inapplicable due to their degrading effects. This makes double layer capacitors no-wadays the only suitable choice. DLCs come with several advantages, such as long lifetime due to almost infinite recharge cycles, charging simplicity without the necessity of complex charging circuits, as well as easy determination of charge level.The very low energy overhead of both proposed systems of typically <30µA leakage, compa-red to energy levels in other systems (about 500µA) makes these systems more appropriate for the use in applications where solar energy income is limited.

Low-Energy Protocol: This work is an extension of the work “Basic Low-Energy Protocol” and is in its initial phase. The objective is to investigate how a saleable synchronous network can be efficiently designed. A simulation framework is used to explore different networking strategies. On the basis of the simulation, implementation of a network will be made.

4.3.3 Environmental monitoring systemIn June 2009 the STC program set up a wireless sensor network for ground-level CO2 measu-rements in Swedish forests. The environmental monitoring system is a collaboration between the different sub-programs within the STC program.


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The deployment is a small wireless network for monitoring the ground-level CO2 levels at six different locations. The node consists of two parts: the CO2 sensor that is placed close to the ground and the wireless communication device attached to a tree 1-1.5 meters above ground. The CO2 sensors comes from Senseair.

The network structure is depicted below. The deployment consist of six wireless CO2 sen-sors of which three of them is located in a fertilized area of the forest and the other three in a non-fertilized region. The objective is to find out if there are any differences in ground CO2 emissions between these two regions. The site is located outside Bispgården.

The sensor nodes are communicating in a tree-topology network using a TDMA-based pro-tocol. The basestation collects sensor information once every ten minutes (CO2-level, tem-perature, and humidity) for each node and passes it on to the web-server located at Campus Sundsvall.

A primitive CO2 sensor for ground emission measurement was constructed, see picture below.

GSM/GPRS

GSM/GPRS

Fertilized Non fertilized


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The wireless communication platform (SENTIO-e2) is equipped with a 433MHz radio trans-ceiver that has a communication range of 800 meters in Line-of-Sight (LoS). At the deploy-ment site we were encountering dense vegetation which brought down the communication range to tenths of meters. The picture below shows the typical environment.

The network delivered sensor information for a couple of weeks. The week point was the packaging of the sensor units that, after several days of heavy raining, led to network failure. Packaging of gas sensors located close to ground is a challenge because it must be properly sealed against water and moisture and at the same time exposed to the ambient air.

Below you can see an example of what we received from the field. In the transitions from night-to-day (05:00 – 06:00) and day-to-night (21:00 – 22:00) distinct peaks in CO2 levels can be observed.


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4.3.4 Initiated Co-operationsBiomechanics: A monitoring system for in situ measurement of alpine skiers’ upper body motions is developed. The objective is to understand the stress of the complex neck muscula-ture of the skier. The wireless 3D motion sensor is used and five of these devices form an on-body wireless network. The sensor data will be used for a biomechanical model. The work is made in co-operation with Dr. Jonas Danvind at the Sportstech group in Östersund.

Characterization of RF environment in vessel machine room: In co-operation with Kongsberg Maritime (Trondheim, Norway) we have in a pre-study investigated the condi-tions for a wireless network in vessel machine rooms. This type of environment is considered to be extremely difficult for RF communication with irregular metal objects blocking line-of-sight paths. The picture below shows parts of the interior of the machine room.

The test was carried out on a trip between Lübeck and Gothenburg in a vessel (length: 190 meters, 20,000 DWT). Wireless devices based on IEEE802.15.4 were used (SEN-TIO32). The RSSI parameter and “packet correct rate” were measured between a large numbers of positions in the machine room.

The graph below illustrates typical results obtained. All available channels (16) are characterized and large variations in (PCR) between different channels were found due to multipath fading. However, it was also found that there was always more than one channel available with high (PCR). The con-clusion we can make is that star topology network can be used if the communication protocol includes a mechanism for adaptive channel selection.


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4.4 Sensor TechnologiesLow-cost sensor solutions in NIR radiation area, portable instrument for spectroscopic iden-tification alpha emitters, X-ray imaging microscope for material resolving and development of X-ray imaging sensors are in a continued development during 2009. New started project are development of radiation hard position detector and fiber-optical sensors in health-care applications

Development of low-cost thermal detector for detection of CO2 based indoor climate control: By spreading the thermopiles in a thermopile structure more evenly and run-ning developed design optimization software, the sensitivity has been increased and the response time decreased. Demon-stration of this new designed and optimised detector in a real application show an excellent sensitivity and low noise.

Figur 1: Image shows a top view of a fabricated Al/Bi thermopile with 4 µm SiO2/SU-8 2002 membrane. The central part of the images has been magni-

fied in order to highlight the thermocouple junctions.

Portable instrument for detection of Polonium and other alpha emitters: Due to the increased threat of terrorism and other incidents where radioactive materials are dispersed there is an increasing need to detect the presence of such materials. Alpha is much more dif-ficult to detect than beta or gamma radiation because of the attenuation in air, however alpha particles is very dangerous to humans if inhaled or ingested due to the high kinetic energy of alpha particles. Therefore there is a need for a portable instrument which can, by an electro-static field, collect airborne dust particles with radioactive contaminations. The instrument should be able to determine which type of radioactive material it is and gives therefore more information than for example a Geiger-Muller counter. A prototype instrument has been built. To test the instrument, a radioactive source of 226Ra has been used. Radium decom-poses into 222Rn with a half-life time of ~1.6 year. The prototype instrument displays an excellent energy resolution and sensitivity in the detection of decay products like 218Po and 214Po. Further work includes development of portable read-out-electronics and decreasing the volume of measurement chamber to a more suitable size.

Energy resolving X-ray imaging detectors: Colour x-ray, i.e. energy resolved x-ray, by using a pixel detector system, where each pixel has the possibility to discriminate the en-ergy of an x-ray photon have been demonstrated. The idea to represent the interval of x-ray energies to “red”, “blue”, “green” nomenclature gives the possibility to use industrial video presentation technique to monitor the distribution of photon energies into an image.

Tin

Gadolinium

Iodine


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Development of X-ray imaging sensors: Different types of X-ray imaging detectors have been developed, for example a detector with 220x220 um pixel detectors where spectral performance is more important than spatial resolu-tion. The size of the detector is 15x15 mm. Development of the detector have been done by implementing n-type chan-nel stop in between the pixel. The improvement have been verified by simulation and demonstrated experimentally.

Radiation hard lateral position sensitive detector: Position sensitive detectors can be used in a variety of applications. Non-contact measurements, displacement meters, and proximity sensing are some examples of applications. Moving from visible light to UV-light means photons with higher energies. This increased energy of photons gives high stress in the silicon silicon-dioxide interface which can give problem with long term stability. The pro-ject is therefore to improve the radiation hardness of the interface. Moreover, position sen-sitive detectors for electrons in the range of 1 keV and 15 keV is of interested in applications as scanning electron microscopes. The developed detector is therefore also going to be tested with low energetic electrons, since improved sensitivity for UV-light is also expected to have improved sensitivity to electron. Next paragraph gives more detail about the simulation of low energetic electrons.

Figure 2. Measurement in Christer Fröjdh’s basement for 6 hours. The spectrum of 218Po and 214Po is clearly visible.


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Figure 4. End of pentafiber

High resolution electron detector: The project is making use of Geant4 - geometry and track-ing platform for the simulation of the passage of particles through matter using Monte Carlo methods. A goal of the project is to track the passage of a bombarding particle (electron in this case) (1Kev – 15KeV) through the detector. This involves considering possible interac-tions and decay processes. In addition, the detector response is recorded when the electron particle passes through the volume of the detector - an approximating how a real detector would respond.

Development of disposable fiber-optical sensor technology in health-care appli-cations: New fiber optic sensor technology is developed for use in health care applications. First demonstrator to develop is a temperature and pH-sensor with small dimensions. A com-bination of advanced optical fibers with 5 capillary holes i.e. pentafibers and doped Sol-Gel material processing is an important building block in the development of the sensor.

High resolution electron detector: The project is making use of Geant4 - geometry and tracking platform for the simulation of the passage of particles through matter using Monte Carlo methods.

One goal of the project is to track the passage of a bombar-ding particle (electron in this case) (1Kev – 15KeV) through the detector. This involves considering possible interactions and decay processes. In addition, the detector response is recorded when the electron particle passes through the vo-lume of the detector - an approximating how a real detector would respond

Figure 3. Simulation of optical generation in a wafer generated by 855nm infrared radiation.


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4.5 Sensor-based Services

The MediaSense and InterakTiV projects continued to make good progress producing new results during 2009.

Sensor information gateways: The project researched new functionality in bridging access to information from sensors and sensor networks and bringing this into service support in mobile systems (e.g., IMS) and the Internet. The new functionality enabled us to add sensors continuously without changing the platform through to be individually reachable on the Internet. Our initial approach is to, via Bluetooth, connect Wireless Sensor Networks (WSN) gateways to mobile phones or other devices and we have developed a low-power platform for communicating with a multitude of sensors.

User and sensor information on the Internet and in mobile services: The activities in 2009 were focused on consolidating the initial technical platform and means for aggregating and distributing user information from sensor information. This support is pivotal to the pro-ject since the new service behavior which the platform should enable requires access to such information.

Seamless media services: Simultaneously, we created new support for seamless multi-media services. This support combined with the user and sensor information was used to demonstrate seamless multimedia services between mobile devices and media centers in homes.

Demonstration of research: A residential energy-monitoring application combined with sensor-driven seamless multimedia services between an android mobile and a home media center (connected homegateway) was demonstrated at the STC Expo 2009 and due for de-monstration at the Mobile World Congress in Barcelona early in 2010. See also http://www.miun.se/ITM/Forskning/Informations--och-kommunikations-system/Forskningssamarbete/.


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5 Awards in 2009

5.1 The Sundsvall 42 scholarship Each year the association Sundsvall 42 award a stu-dent who demonstrate a promising idea with a scho-larship of 25 000 sek. In 2009 Stefan Forsström, who is a PhD student at Sensible Things that Communicate, won the scholarship for his examination work ”Fast location – scoped context dissemination”.

His work is about gathering users information and to utilize this information to offer more smart services. Stefan presents an example in his work about how cars can communicate with each other. For exampel, if you drive along the freeway and meet another car, that car could send information to your car about the comming road conditions. Since the technique already exists this could be possible today but first we need to equipe all cars with sensors and mobile broadband. That is one of the examples that Stefan brings up in his work.

Now Stefan will continue his research within the STC-project Sensor-based Services.


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5.2 STC winner in Swedish Embedded AwardPhD student Peng Cheng and master student Yan Yang at Sen-sible Things that Communicate won the Micro/Nano category in the Swedish Embedded Award 2009. Their winning contribution is a Stator-free RPM Sensor that in contrast to all other existing sensors that are based on two coupled parts, only consists of one part that is mounted on the rotating shaft. This solution simplifies the sensor design and allows more flexibility in installation. One interesting property of this sensor is that it gives higher accuracy for higher RPMs.

With the nomination Peng Cheng and Yan Yang got the opportunity to exhibit their project at the Scandinavian Technical Fair in Stockholm. That is where the grand prize ceremony took place and the prize was awarded by IM Embedded Technology and Swedish Association of Electronics Industries, KK-foundation with TeknIQ and MinST, the magazine Elektronik i Norden and Scandinavian Technical Fair. Besides the opportunity to exhibit and all the honor that comes along with the prize, Peng Cheng and Yan Yang also won a full page advertise in the magazine “Elektronik i Norden”.

The students supervisor prof. Bengt Oelmann is very proud when he says that this award confirms that Mid Sweden University has great students and a high quality of the master and bachelor programmes. And it is all made possible by the research program Sensible Things that Communicate.


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6 PhD examinations during 2009In 2009 Sensible Things that Communicate had two PhD-students that defended their thesis. First one out, in January, was Dr. Najeem Lawal and in the autumn it was Dr. Claes Mattssons turn.

6.1 Dr. Najeem Lawal

In January Najeem Lawal was the first one out to defend his doctoral thesis “Me-mory Synthesis for FPGA Implementation of Real-Time Video Processing Sys-tems.”

In this thesis, a method and a tool to enable efficient memory synthesis for real-time video processing systems on field programmable logic array are presented. In real-time video pro-cessing system (RTVPS), a set of operations are repetitively performed on every image frame in a video stream. These operations are usually computationally intensive and, depending on the video resolution, can also be very data transfer dominated. These operations, which often require data from several consecutive frames and many rows of data within each frame, must be performed accurately and under real-time constraints as the results greatly affect the accuracy of application. Application domains of these systems include machine vision, object recognition and tracking, visual enhancement and surveillance.

Developments in field programmable gate array (FPGAs) have been the motivation for choosing them as the platform for implementing RTVPS. Essential logic resources required in RTVPS operation are currently available optimized and embedded in modern FPGAs. One such resource is the embedded memory used for data buffering during real-time video pro-cessing. Each data buffer corresponds to a row of pixels in a video frame, which is allocated using a synthesis tool that performs the mapping of buffers to embedded memories. This ap-proach has been investigated and proven to be inefficient. An efficient alternative employing resource sharing and allocation width pipelining will be discussed in this thesis.

A method for optimised use of these embedded memories and, additionally, a tool sup-porting automatic generation of hardware descriptions language (HDL) modules for synthe-sis of the memories according to the developed method are the main focus of this thesis. This method consists of the memory architecture, allocation and addressing. The central objective of this method is optimised use of embedded memories in the process of buffering data on-chip for an RVTPS operation. The developed software tool is an environment for generating HDL codes implementing the memory sub-components.


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The tool integrates with the Interface and Memory Modelling (IMEM) tools in such a way that the IMEM’s output - the memory requirements of a RTVPS - is imported and processed in order to generate the HDL codes. IMEM is based on the philosophy that the memory re-quirements of an RTVPS can be modelled and synthesized separately from the development of the core RTVPS algorithm thus freeing the designer to focus on the development of the algorithm while relying on IMEM for the implementation of memory sub-components.

6.2 Dr. Claes MattssonIn september it was Dr. Claes Mattssons turn to defend his doctoral thesis called ”Design, Fabrication and Optimization of Thermal Radiation Detectors Based on Thin Polymer Membranes.”

The number of applications in which infrared radiation sensors are used is increasing. In some applications, the cost of the sensor itself is an issue, and lowcost solutions are thus required. In this thesis, the investigations have related to the use of thin polymer membranes in thermal infrared sensors, such as bolometers and thermopiles.

Infrared sensors are usually subcategorized into photonic sensors and thermal sensors. For detection of infrared radiation using a photodetector, there is a requirement for low band-gap material. By cooling the sensor, the noise can be reduced. However, this also makes infrared photodetectors rather expensive, and not an alternative for low-cost applications. In thermal sensors, the heat generated from the incident infrared radiation is converted into an electrical output by means of a heat sensitive element. The thermal sensors usually operate at room temperature, which makes them a low-cost alternative. The responsivity and response speed is, on the other hand, higher and shorter respectively in photodetectors. The basic structure of thermal sensors consists of a temperature sensitive element connected to a heat sink through a structure with low thermal conductance. It is common to use thin membranes

Dr. Najeem Lawal Source of funding KK-Foundation

Doctorial Thesis Memory Synthesis for FPGA Implementation of Real-Time Video Processing Systems


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of Silicon or Silicon Nitride as thermal insulation between the heat sink and the sensitive element. In comparison, polymers have a thermal conductance that is lower than in these materials, and this increases the generated temperature in the sensitive element. The epoxy based photoresist SU-8 has a low thermal conductivity and requires no additional processing equipment. This thesis presents a new application of SU-8 as a closed membrane in a thermal sensor.

The concept was initially demonstrated by fabricating a nickel bolometer and titanium/nickel thermopile structure with a 5 µm SU-8 / SiO2 membrane. The characterization of these com-ponents showed that the concept of SU-8 as a membrane material would work. However, for the sensor responsivity to be able to compete with commercial thermal sensors the structu-res, some optimization was required. Since the thermopile generates its own voltage output and requires no external bias, the optimizations were focused on this structure. In circuit design, it is common to use device optimization. For design optimization of thermopiles with closed membranes, few developed tools exist. An optimization tool using iterative thermal simulations was developed and evaluated. A new thermopile structure, based on the opti-mization results, was both fabricated and characterized. Using an infrared laser with a small spot, the measured responsivity of the manufactured thermopile was higher than that of a commercial sensor. In the case of a defocused spot and for longer wavelengths, the infrared absorption in the absorption layer reduces and degrades the responsivity.

The thermopile was further evaluated as a sensor in a carbon dioxide meterapplication based on the NDIR principle. An increase in the CO2 concentration demonstrated a clear decrease in the thermopile voltage response, as was expected. By normalizing the voltage response and comparing it with a commercial sensor, this showed that the SU-8 based ther-mopile is more sensitive to the CO2 concentration.

Dr. Claes Mattsson Source of funding Mid Sweden University and KK-Foundation STC@MIUN

Doctorial Thesis Design, Fabrication and Optimization of Thermal Radiation Detec-tors Based on Thin Polymer Membranes.


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7 New staff and promotionsProfessor Christer FröjdhChrister Fröjdh became a professor in solid state electronics at Mid Sweden University in 2009. His research is focused on development of semiconductor detectors for radiation detection and measurement. The applications include X-ray imaging with energy resolution, measurement of Radon levels as well as detection of hazardous radiation levels in security applications. He is currently the deputy spokesman of the MEDIPIX2 collaboration at CERN and the Chairman of the Scientific Committee for the International Workshop on Radiation Imaging Detectors. Christer got his PhD at KTH in 1998 and became an Associate Professor at KTH in 2000. He has been employed at Mid Sweden University and its predecessors since 1984.

Associate professor Göran ThungströmGöran Thungström has been promoted to Associate profes-sor in Radiation Detectors at Mid Sweden University, in Oc-tober 2009. His docent lecture on radiation detectors - basic pincipals, detector processing and different types of applica-tions, was called ”Radiation Detectors and its Applications”. Göran Thungström is also project leader for the STC sub program Sensor Technologies.

Assistant professor Börje NorlinBörje Norlin became an Assistant Professor in electronics at Mid Sweden University in 2009. His research involves all type of radiation measurements and focus on energy sensi-tive X-ray imaging sensors, “Colour X-rays”. This techno-logy can be used to measure the material composition of an object directly in an X-ray image, ideal for industrial quality measurements and safety applications. Börje got his MSc in Engineering Physics and Radiation Science from Uppsala University and have been employed by Mid Sweden Uni-versity since the first day of the new millennium 2000.

Professor Christer Fröjdh

Associate Prof. Göran Thungström

Assistant Prof. Börje Norlin


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Assistant professor Jan ThimJan Thim became an Assistant Professor in electronics at Mid Sweden University in 2009. His research focus is currently on optical online measurement systems for the characterization of paper. He is also involved in research concerning color X-Ray imaging systems, where the Electronics Design Divi-sion is a part of the Medipix collaboration. In this project, the focus has been on alternative readout architectures and on X-Ray image enhancement.

Assistant professor Kent BertilssonKent Bertilsson became an Assistant Professor in electronics at Mid Sweden University in 2009. He is leading a research project in Power Electronics developing high frequency Switching Mode Power Supplies. At higher switching fre-quency less energy need to be stored in reactive components enabling more compact designs but also increased losses in transformer and semiconductor devices. Kent got his M.Sc. from Mid Sweden University in electronics 1999 and Ph.D in the area of semiconductor devices from KTH in 2004.

Assistant professor Johan SidénJohan Sidén became an Assistant Professor in Electronics at Mid Sweden University in December 2009. His research inte-rests include RFID, printed electronics, antennas, sensors and the combination of these terms. Johan holds his position as an Assistant Professor at 50% of his time while the remaining time is spent with technology development at the company Sensible Solutions Sweden AB, a spin-off from the Electro-nics Design Division. Sensible Solutions is specialized in low cost wireless sensors for widespread applications rang-ing from measuring liquid levels in diapers and detecting moisture in house walls to ecological detection of wildland fires in remote areas.

Assistant Prof. Kent Bertilsson

Assistant Prof. Jan Thim

Assistant Prof. Johan Sidén


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Research assistant Claes MattssonAt the end of 2009 Claes Mattsson was given the position as Research Assistant in electronics at Mid Sweden Univer-sity. Claes received his MSc in Electrical Engineering from Mid Sweden University in 2003. He was later employed as a PhD student at the Electronic Design Division. His research involves development and fabrication of radiation detectors mainly in silicon technology and in related micromechanical technologies for developing infrared detectors. His most re-cent research has been focused on development of a low cost infrared detector. Carbon dioxide absorbs infrared radiation at specific wavelengths, and by using an infrared radiation source and an infrared detector the carbon dioxide concen-tration in air can be determined.

Research assistant Najeem LawalNajeem Lawal became a Research Assistant at the Electro-nics Division at Mid Sweden University in June 2009. His research involves machine vision where a combination of state-of-the-art development software and hardware are employed in implementing vision system. In particular, Najeem focuses on the power consumption of vision system algorithms and works on how it can be optimized through algorithm optimization and implementation platform ex-ploration. Thus achieving longer battery life for the vision system which are often application specific and embedded in larger industrial system. Najeem came to Sweden in Septem-ber 2003 from Nigeria to study for Masters degree, which he completed in September 2004. He was given the doctoral research opportunity in January 2005 and he obtained his doctoral degree in January 2009.

Research Assistant Najeem Lawal

Research Assistant Claes Mattsson


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7.1 New PhD students within STC and supporting projects

In 2009, 13 new PhD students started within the Sensible Things that Communicates various projects . Here below is a short presentation of each and every one of them.

Naeem AhmadMSc from Linköping UniversitySource of funding: Higher Education Commission of PakistanHead Supervisor : Prof. Bengt Oelmann

His research project is hardware architectures and their im-plementation for wireless imaging sensors.

Stefan ForsströmMSc from Mid Sweden UniversitySource of funding: Regional EU target 2 funds, regional public sector, and industry such as Ericsson Research and Telia.Head Supervisor : Prof. Theo Kanter Stefan received his M.Sc. in Computer Engineering from Mid Sweden University in 2009 and is pursuing licentiate degree with the topic of “Scalable Search and Browse in Distributed Context Networks”. His research is within Sensible Reality, under the MediaSense and the STC projects, where his task is to develop Context Aware applications and services, utili-zing sensors and actuators to create the intelligent services of tomorrow. In the research, these services are mostly aimed towards java capable mobile phones such as Google An-droid. Stefans task is to develop networks that can exchange context information and to maintain the real time aspects in these Context Networks which will enable rich applications and services. The research also include investigating the ideas of having a digital self, a presence entity or presentity, which follows you around manifesting in intelligent devices around you.

PhD Naeem Ahmad

PhD Stefan Forsström


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Anzar Alam MSc from Mid Sweden UniversitySource of funding: STC@MIUNHead Supervisor : Prof. Mattias O’Nils

Anzar is doing research in optical online measurement of to-pography of paper. His main focus is to study and optimize illumination, camera and setup parameter’s effect on dyna-mic range and measurement accuracy.

Mohammad ImranMSc from Linköping UniversitySource of funding: Higher Education Commission of PakistanSupervisors: Prof. Mattias O’Nils and Dr. Najeem Lawal

Imran has a background education in DSP algorithm optimi-zation with special interest in DSP arithmetic during his mas-ters degree. He now combines his skills with current camera technology and hardware processing platform to perform research in the area of real-time video processing systems. The focus of Imran’s research is on investigation and de-velopment of strategies for partitioning between different computational platforms for low-energy implementation of smart cameras.

Victor KardebyMSc from Mid Sweden UniversitySource of funding: Regional EU target 2 funds, regional public sector, and industry such as Ericsson Research and Telia. Head Supervisor : Prof. Theo Kanter

Victor received his M.Sc. in Computer Engineering from Mid Sweden University in 2009 and is pursuing licentiate degree on the topic of “Naming and Discovery in Composable Con-text Networks”.

PhD Anzar Alam

PhD Mohammad Imran

PhD Victor Kardeby


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Shahzad KhurramMSc from Linköping UniversitySource of funding: Higher Education Commission of PakistanHead Supervisor : Prof. Bengt Oelmann

Shahzad’s research project is a study of hardware architec-tures for complex wireless sensors with high computational capacity in-sensor. The first case to be studied is a vibration sensor with FFT computation cabability.

Abdul Waheed Malik MSc from Linköping UniversitySource of funding: Higher Education Commission of PakistanHead Supervisor : Associate Professor Benny Thörnberg Waheed is doing his PhD on optical real-time measurement systems for position and orientation in at most six dimen-sions of freedom. These are machine vision systems which are suitable for aggressive parallelization and implementa-tion on Field Programmable Gate Arrays (FPGA). He is plan-ning to generalize parts of these vision systems and create a CAD tool for the designing of machine vision on FPGA.

Jawad SaleemMSc from Linköpings UniversitySource of funding: Higher Education Commission of PakistanHead Supervisor : Assistant Professor Kent Bertilsson

Jawad Saleem will work in the Power electronics group in the area of resistance welding in collaboration with IBErobot and Timrå Elbyggnad. Resistance welding is when a high current is used to weld two sheets of metal together. Tradi-tional equipments are working at the grid frequency 50/60Hz and the welding current are up to about 50kA. For thicker material really high currents up to 100 or even 200 kA is a desired. In this case it is necessary increasing the switching frequency to reduce the transformer size ant utilize 3-phase supply to the unit.

PhD Abdul Waheed Malik

PhD Shahzad Khurram

PhD Jawad Saleem


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David KrapohlDipl.-ing from Aachen University of Applied Science, GermanySource of funding: Faculty of Science, Technology and MediaHead Supervisor : Associate Professor Göran Thungström

The project is focused to investigate possible new processing steps to implement in the manufacturing of position sensitive detectors, where the termination of silicon interface have im-portant influence on the stability of responsivity for shallow absorbed irradiation. The work is done with support from SiTek Electro Optics in Gothenburg.

Abdul MajidMSc from Linköpings UniversitySource of funding: Higher Education Commission of PakistanHead Supervisor : Assistant Professor Kent Bertilsson Abdul Majid will work with digital control of switch mode power supplies in the power electronics group. Research has been performed in the group focusing on transformer and the switch topology but there are still challenging problems in the drive logic for such a converter. The challenges that arises here are how to assure that the converter operate at optimal conditions in a regulated circuit without the pos-sibility of tuning manually. At lower frequencies this can be done be sampling the signal waveforms and decide where to switch the transistor for maximum efficiency. At a few MHz this option is not available using technology that is afforda-ble in such an application

Fredrik LindeMSc from Luleå Technical UniversitySource of funding: Faculty of Science, Technology and MediaHead Supervisor : Prof. Bengt Oelmann

Fredrik is investigating ultra-low energy communication protocols for wireless sensor networks. The targeted applica-tion area is environmental monitoring.

PhD David Krapohl

PhD Abdul Majid

PhD Fredrik Linde


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Khursheed KhursheedMSc from Linköping UniversitySource of funding: Higher Education Commission of PakistanHead Supervisor : Prof. Mattias O’Nils and Dr. Najeem Lawal

Khursheed has a background education in DSP algorithm optimization with special interest in DSP arithmetic during his masters degree. He now combines his skills with current camera technology and hardware processing platform to perform research in the area of real-time video processing systems. The focus of Khursheed’s research is on investiga-tion and development of strategies for partitioning between local and centralized computing to achieve low-energy per-formance in the smart-camera node.

Jamie WaltersMSc from Birkbeck University of LondonSource of funding: Regional EU target 2 funds, regional public sector, and industry such as Ericsson Research and Telia.Head Supervisor : Prof. Theo Kanter

Jamie received his M.Sc. in Advanced Information Systems from the Birkbeck University of London in 2007 and is pursuing licentiate degree on the topic of “Distributed ser-vice networks”.

PhD Khursheed Khursheed

PhD Jamie Walters


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8 Publications 2009This is a list of publications produced during 2009 and connected to STC:

Theo Kanter, Stefan Forsström, Victor Kardeby, Jamie Walters, Patrik Österberg, Stefan Pet-tersson, “Ubiquitous Mobile Awareness from Sensor Networks”, Enabling Context-Aware Web Services: Methods, Architectures, and Technologies, Publisher: Chapman and Hall/CRC, 2009

Theo Kanter, Patrik Österberg, Jamie Walters, Victor Kardeby, Stefan Forsström, Stefan Pet-tersson, “The MediaSense Framework”, ICDT’09

Theo Kanter, Stefan Pettersson, Stefan Forsström, Victor Kardeby, Roger Norling, Jamie Walters, Patrik Österberg, ”Distributed Context Support for Ubiquitous Mobile Awareness Services”, Chinacom 2009

Stefan Forsström, Victor Kardeby, Roger Norling, Theo Kanter, ”Dissemination of Anonymi-sed Context Information by Extending the DCXP Framework”, Monami 2009

Theo Kanter, Stefan Pettersson, Stefan Forsström, Victor Kardeby, Patrik Österberg, “Ubiqui-tous Mobile Awareness from Sensor Networks”, UbiIslands 2009

Claes Mattsson, Göran Thungström, H. Rodjegard, Kent Bertilsson, Hans-Erik Nilsson, Hans Martin, “Experimental evaluation of a thermopile detector with SU-8 membrane in a carbon dioxide meter setup” IEEE Sensors Journal, vol. 9, n 12, p 1633-8, Dec. 2009

Claes Mattsson, Göran Thungström, Kent Bertilsson, Hans-Erik Nilsson, Hans Martin, “Fabrication and characterization of a design optimized SU-8 thermopile with enhanced sen-sitivity,” Measurement Science & Technology, vol. 20, n 11, p 115202 (9 pp.), Nov. 2009

Henrik Andersson, Anatoliy Manuilskiy, Göran Thungström, A. Lundgren, Hans-Erik Nils-son, ”Principle of FT spectrometer based on a lateral effect position sensitive detector and multi channel Fabry-Perot interferometer Measurement,” vol. 42, n 5, p 668-71, June 2009

L. Herrnsdorf, M. Björk, B. Cederquist, Claes Mattsson, Göran Thungström, Christer Fröjdh, “Point dose profile measurements using solid-state detectors in characterization of Compu-ted Tomography systems,” Nuclear Instruments & Methods in Physics Research, Section A (Accelerators, Spectrometers, Detectors and Associated Equipment), vol. 607, n 1, p 223-5, 1 Aug. 2009


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Claes Mattsson, Kent Bertilsson, Göran Thungström, Hans-Erik Nilsson, Hans Martin, “Thermal simulation and design optimization of a thermopile infrared detector with an SU-8 membrane,” Journal of Micromechanics and Microengineering, vol. 19, n 5, p 055016 (9 pp.), May 2009

Börje Norlin, Christer Fröjdh, “Characterisation of spectral performance of pixellated X-ray imaging detectors in a microscopy setup,” Nuclear Instruments & Methods in Physics Re-search, Section A (Accelerators, Spectrometers, Detectors and Associated Equipment), vol. 607, n 1, p 199-201, 1 Aug. 2009 Mattias O’Nils, Jan Thim, Börje Norlin, Bengt Oelmann, “Threshold modulation for continu-ous energy resolution with two channels per pixel in a photon counting X-ray image detec-tor,” Nuclear Instruments & Methods in Physics Research, Section A (Accelerators, Spectro-meters, Detectors and Associated Equipment), vol. 607, n 1, p 236-9, 1 Aug. 2009

Qinghua Wang and Tingting Zhang, “Bottleneck Zone Analysis in Energy-Constrained Wireless Sensor Networks”, Communications Letters, IEEE Volume 13, Issue 6, June 2009 Page(s):423 – 425.

QinghuaWang, Tingting Zhang, “Characterizing the traffic load distribution in dense sensor networks,” to appear in Proc. of the 2nd International workshop on Wireless Sensor Net-works: Theory and Practice (WSN’09) in conjunction with IFIP NTMS 2009, Cairo, Egypt, December 2009.

Xin Huang, Y. He, Y. Hou, L. Li, L. Sun, S. Zhang, Y. Jiang, and Tingting Zhang, “Privacy of Value-added Context-aware Service Cloud,” in Proc. of CloudCom2009 December 2009.

Xin Huang, Tingting Zhang, Y. Hou, ID Management among Clouds, First International Con-ference on Future Information Networks, October, 2009.

Qinghua Wang, Tingting Zhang, “A multihoming extention of wireless node implementation in ns-2”, 2009 Fourth International Conference on Communications and Networking in China , August 26-28, 2009, Xi’an, China.

Qinghua Wang and Tingting Zhang, “Traffic load analysis in large-scale and dense wireless sensor networks“, in Proc. of the 6th Swedish National Computer Networking Workshop and 9th Scandinavian Workshop on Wireless Adhoc Networks (SNCNW-adhoc’09), Uppsala, Sweden, March 2009.

Qinghua Wang and Tingting Zhang, “Simulating wireless multihomed node in ns-2 “, in Proc. of the 6th Swedish National Computer Networking Workshop and 9th Scandinavian Workshop on Wireless Adhoc Networks (SNCNW-adhoc’09), Uppsala, Sweden, March 2009.


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Qinghua Wang and Tingting Zhang, “A survey on security in wireless sensor network ne-towkrs “, in Security in RFID and Sensor networks, Y. Zhang and P. Kitsos, Eds. CRC press, Taylor Francis Group 2009, Chapter 14, pp. 293-320.

Tomas Unander & Hans-Erik Nilsson, (2009). Characterization of Printed Moisture Sensors in Packaging Surveillance Applications. IEEE Sensors Journal, vol. 9: 8, ss. 922-928.

Theo Kanter, (2009). Foreword : Context-Aware Mobile and Ubiquitous Computing for Enhanced Usability: Adaptive Technologies and Applications. I Context-Aware Mobile and Ubiquitous Computing for Enhanced Usability : Adaptive Technologies and Applications. IGI Global.

Jan Thim & Börje Norlin, (2009). Noise Coupling in Digital X-Ray Imaging. I Medical Ima-ging: Principles, Detectors, and Electronics. Wiley.

Qinghua Wang & Tingting Zhang (2009). Security in Wireless Sensor Networks. I Security in RFID and Sensor Networks. Auerbach Publication.

Omeime Esebamen, Börje Norlin & Göran Thungström, (2009). Spectral Performance of Pho-ton Counting Pixel Detector Using Attenuation Spectra for Test Samples. I Nuclear Physics Methods and Accelerators in Biology and Medicine,. New York : . S. 177--179.

Stefan Forsström, Victor Kardeby, Jamie Walters, Roger Norling, & Theo Kanter, (2009). Dis-semination of Anonymised ContextInformation by Extending the DCXP Framework. I First International ICST Conference on Mobile Networks And Management : Doctoral Student Colloquium.

Anna Fröjdh, Erik Fröjdh, Göran Thungström, Christer Fröjdh, Börje & Norlin, (2009). Pro-cessing and characterization of a MEDIPIX2-compatible silicon detector with 220 um pixel size. I 11th International Workshops on Radiation Imaging Detectors.

Erik Fröjdh, Anna Fröjdh, Börje Norlin & Christer Fröjdh, (2009). Spectral response of a sili-con detector with 220 um pixel size bonded to MEDIPIX2. I 11th International Workshop on Radiation Imaging Detectors.

Linda Karlsson & Mårten Sjöström, (2009). Multiview plus depth scalable coding in the depth domain. I 2009 3DTV-Conference: The True Vision - Capture, Transmission and Dis-play of 3D Video : Potsdam, Germany, May 04-06, 2009.

Lisa Nordin, Mattias O’Nils, Per Engstrand, Roland Bäck, Christer Sandberg & Olof Ferritsi-us, (2009). Measurement and prediction of dewatering characteristics for mechanical pulps using optical fibre analyzers. I Proceedings of the International Mechanical Pulping Confe-rence.


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Rahim Rahmani, Theo Kanter & Christer Åhlund, (2009). Active Queue Management Con-troller to capture bursty traffic by Fuzzy Controller for Multimedia Traffic in Heterogeneous Networks. I Ninth IEEE Malaysia International Conference on Communications (MICC 2009).

Karl W Sandberg, Theo Kanter & Yan Pan, (2009). Mobile technology as part of the research agenda on democracy. I The 13th International conference on Human-Computer Interaction.

Jan Thim, Anatoliy Manuilskiy, Mattias O´Nils, Benny Thörnberg, J Lindgren & J Lidén, (2009). The Impact of Surface Movement in Online Paper Topgraphy Cahracerization Using Light Triangulation. I Proceedings fo the Papermaker´s Research Symposium.

Jan Thim, Börje Norlin, Mattias O’Nils, Suliman Abdalla & Bengt Oelmann, (2009). Realizing Increased Sub-pixel Spatial Resolution in X-Ray Imaging using Displaced Multiple Images. I 11th International Workshop on Radiation Imaging Detectors.

Benny Thörnberg & Najeem Lawal, (2009). Real-time Component Labelling and Feature Ex-traction on FPGA. I IEEE Proceedings on International Symposium on Signals, Circuits and Systems.. S. 217--220.

Qinghua Wang & Tingting Zhang, (2009). Simulated Wireless Multihomed Node in NS-2. I The Sixth Swedish National Computer Networking Workshop and Ninth Scandinavian Workshop on Wireless Adhoc Networks.

Qinghua Wang & Tingting Zhang, (2009). A Multi-homing Extension of Wireless Node Im-plementation in Ns-2. I The 2009 Fourth International Conference on Communications and Networking in China : ChinaCom’09.. S. 751--756.


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9 STC@MIUN research projectsIn the following section we present the ongoing PhD-student projects within STC@MIUN. In addition we also present areas where new PhD students will be allocated during 2009 on-wards.

Project presentations

Online paper topography measurements in paper plant

Soft-IP Interface Modification Methodology

Hardware Centric Machine Vision for High Precision COG

Optipos - Optical Position Measurement in Real-time for Consumer Products

Development of Low-cost Thermal detector for CO2 Based Indoor Climate Control

Energy resolving X-ray imaging detectors

Development of Radiation Hard Position Detecting Devices

Fast Measurement of Radon in buildings

Development of pixelated X-ray imaging sensors in silicon

High Frequency Switch Mode Power Supplies

Development of disposable fiber-optical sensor technology in health-care applications

Wireless Visual Sensor Networks

High resolution Electron Detector

Stator-free Wireless RPM Sensor

Printed Circuit Board (PCB) Transformers

Battery-less Operation of Wireless Sensor Networks using Solar Energy Harvesting

MediaSense

Influence of paper substrates on the performance of printed electronics

Inkjet printed WORM Memory Card reader

Printed RFID Sensors


Sensible Things that Communicate January 2010

Sensible Things that Communicate


Online paper topographymeasurements in paper plant

BackgroundAn online paper surface measurement prototype has been developed and tested in the Iggesund pilot paper manufacturing machine. The prototype measures micro structural topography on the paper surface. The measurements were taken in a rough industrial environment for different quality of reels at speeds from 0 to 790 m/min. The developed prototype has advantages over conventional measurement systems such as parallel readout and an extremely short time forsurface profile information gathering.

ObjectivesThe developed measurement system consists of a laser triangulation optical module, a digital imaging part and software. Special software was developed for acquisition of laser synchronized images and pre-processing of the images. The objective is to measure paper surface topographyat a maximum velocity of 2000 m/min. Three CCD industrial cameras and laser one light sourcebuilds up and extracts the laser triangulation geometry.

ResultsThe short pulse illumination and a narrow spectrum of the laser source have minimized the impact of harsh industrial environment conditions. The sensitivity of the whole range of the wavelength spectra was found to be 3.3 µm. Three types of reels; coated & uncoatedpaperboards and LWC paper, were analysed.Figure 2 shows spectrums of the results in terms of roughness amplitudes.

Ongoing activitiesFurther improvement in accuracy of measurement device and analysis software is in progress.

Figure 1: The prototype installed in the pilot.

Figure 2: Spectrum of 3 different papers showing different power spectral densities.

For further information contact:

Mohammad Anzar Alam

E-mail: [email protected]

Phone: +46737106210



www.kks.sewww.tillvaxtverket.sewww.miun.se

Soft-IP Interface Modification Methodology

Xiaozhou Meng and Benny ThörnbergITM, Mid Sweden University

GoalsTo propose a Soft-IP Interface Modification Methodology (SIPIMM) for an increased IP portability regarding the communication interface problem.

Communication interface mismatchThe soft-IP portability issue is described in figure 1. The IP integrator chooses the IP with the right functionality and performance and then imports it into their IP component library.Different bus interface protocols are not compatible with each other. In addition, the bus standards are evolving such that a previously developed IP might have an earlier version of interface protocol.

MethodologyTo make efficient reuse of IP and its interfaces, an interface-based soft IP model is introduced. Based on this model, the methodology SIPIMM is proposed to ease the communication interface mismatch problem. There are mainly five steps as follow:

A. IP verification: Verify the functional correctness.B. Interface-based soft IP model: Clarify the boundary. (Fig 2)C. Interface modification: One or more IPCs might be

designed if they are not predefined (Fig 3), then replace the interface with new IPC.

D. IP integration: Integrate the IP in to target system.E. Documentation: User guide, datasheet, test plan etc.

Case StudyAn M-JPEG decoder project (Fig 4) that was downloaded for free from OpenCores. This VHDL project comes with an earlier version of the bus interface and the FPGA vendor and the device family was fixed to Xilinx Virtex II pro. Due to the change of development environment, we were facing a communication mismatch requiring modifications of the interfaces from OPB to Fast Simplex Link (FSL) and from VGA monitor output to Native Port Interface (NPI). We modified these interfaces using the proposed methodology SIPPIM. The IP model is built as figure 5. The final system is shown as figure 6.

ConclusionSIPIMM is based on that computation is divided into functional units which have a distinct separation from communication. The benefit is clearly the increased communication portability for soft IP. In addition, the increased reuse of design works leads to a reduced work load for the IP integrator. A case study is presented to show that this methodology can be efficiently applied on a real-world design. There are lots of essential issues for IP reuse except for interface mismatch. IP design is a mixed topic with technical, financial and legal issues.

References:[1] H. C. van Assen, M. Egmont-Petersen, and J. H. C. Reiber, Daniel

D.Gajski, et al., “Essential Issues for IP Reuse”, Proceedings of ASP-DAC, pp.37-42, Jan. 2000.

[2] M.Keating and .Bricaud, Reuse Methodology Manual: For System-on-a-Chip Designs, 3rd ed. Boston, MA: Kluwer,2002.

On-ChipSystem

Soft IPCore

IPC1

InterfaceBlock

…

ComputationalBlock

Fcn1

Fcn2

Fcnm

…

IPC

IPC

Fig.2. A generalized interface-based soft IP model

Computational Block

Dummy Functions

Data

Control

IPC

Protocol

Fig.3. IPC design with a dummy function in the computation block.

Fig.6. Block diagram of complete SOC including the updated decoder IP.

PLBMemory

MicroBlaze

TFT

DecoderIP

PLB

FSL

NPI

M-JPEGDecoder

Reorder

IPC1

IPC2

InterfaceBlock

ComputationalBlock

On-ChipSystem

Decoder IP

Fig.5. Interface-based soft IP model for an M-JPEG decoder.

FPGA Vendor

FPGA Family

IP Vender

OpenSourceVirtex2p

Xilinx

NPI

OPB

FSL

Communication IP ProviderIP IntegratorI t t

Fig.1. Soft-IP portability issue for IP integrator

Fig.4. Block diagram of original decoder project.

M-JPEGDecoder

VGA(VGA Controller

& Reorder)

Decoder IP

OPBIPIF

Mon-itor

Memory

OPB




Hardware Centric Machine Vision for High Precision COG

GoalsTo develop a hardware oriented method for real-time object’s high precision Centre Of Gravity calculation in video.

Precision evaluation versus SNRFrom the variation of COG derived, if the light spots exactly the origin dot of coordinate system and wuSNR ˆσ= , the revised standard deviation formula developed:

( ) SNRy

,x

Nx,ycstd

Ωx,yΩx,y

⋅

≈∑∑∈∈

22

11)(

1 (1)

where x, y the coordinates value of pixels and N the total pixels in the range of light spot.

Algorithm Principles

11x11 convolving with low pass filter

Input video stream

Background subtraction

+Thresholding

B=(In>Th)In B Labelling and

morphologicalfiltering

COGOutput

Algorithm 1:

Algorithm 2:

11x11 convolving with mean value

low pass filter

Input video stream


+Thresholding


morphological filtering

COGOutput 11x11 convolving

with Gaussian smoothening filter

Algorithm 3:

11x11 convolving with mean value

low pass filter

Input video stream


+Thresholding


morphological filtering

COGOutput 11x11 convolving

with Gaussian smoothening filter

Squaring O=P*P

P O

Preprocessing Object processing



Fig. 1. Alternative algorithms

A) B)Fig. 2. Profile of pre-processing filter of Algorithm A) 1, B) 2

Especially hardware oriented preprocessing operator that combined high pass filter with enhancement operator and Gaussian noise filter together, see Fig. 2B. For real-time processing on FPGA, convolving is preferable implemented using the hardware architecture shown in Fig. 3 andsubsequent processing for components labeling and COG calculation based on optimal hardware design on FPGA.

Line Delay1 Line Delay10Line Delay2

1 1 1

10 pixel delay

1 1 1 1 1 1

Computation kernel for preprocessing

Output pixel

Fig.3 Hardware architecture for the preprocessing filter

Experiments250 frame images with 90 light spots captured and images with orwithout a complex synthetic background in Fig. 4 to be simulated.

Fig. 4. Synthetic background added to original images.

Results and ConclusionThe simulation results in Fig.5 show that the new method can not only eliminate the affection of synthesized background, but also improve as high as 195 percent for the sub-pixel precision at SNR=11 and 40 percent for the slope. Through this workanalyses, the suggested hardware architectures are suitable for computation of the developed algorithm.

11 12 13 14 15 16 17 18 19 20 2110

15

20

25

30

35

40

45

50

55Subpixel precision in Column dimension versus SNR

SNR

1/st

dDev

(C)

11 12 13 14 15 16 17 18 19 20 210

20

40

60

80

100


SNR

1/st

dDev

(C)

11 12 13 14 15 16 17 18 19 20 2110

20

30

40

50

60

70

80


SNR

1/st

dDev

(C)

11 12 13 14 15 16 17 18 19 20 2110

20

30

40

50

60

70

80


SNR

1/st

dDev

(C)

Fig. 5. Sub-pixel precision versus SNR for Algorithms

For further information contact:{xin.cheng,benny.thornberg}@miun.se



PROJECT INFORMATION – February, 2010 STC – Sensible Things that Communicate

Mid Sweden University Phone: 0771-975 000STC – Sensible Things that Communicates Fax: 060-14 84 56851 70 Sundsvall Internet: www.miun.se/stc

www.kks.se

OPTIPOS - OPTICAL POSITION MEASUREMENT IN REAL-TIME FORCONSUMER PRODUCTS

BackgroundSystems that can measure their own locations are becoming more frequently used in different applications. A headset for Virtual Reality (VR) presentation must measures its position and orientation in order to track the movement of its user’s head. It is also necessary to measure position and orientation for a handheld printer that operates as a computer mouse, printing text and graphics while it is moved over a large surface.

ObjectivesOptical position measurement methods and its related algorithms and implementations will be investigated in this project. Methods based on prepared environments already exist that can measure an objects position and orientation within a room for 6 Dimensions Of Freedom (6DOF) or in 3DOF over a surface. We intend to investigate if these methods can be enhanced to work in general unprepared environments, if it is possible to optimize these algorithms in order to reduce implementation costs and also if it is possible to automate the estimation of implementation costs for such algorithms.

ResultsFigure 1A show a prototype of a vehicle with optical navigation in 3DOF. The cameras shown under the vehicle is used to monitor a travelled path. Figure 1B show an intelligent camera design for measurement of position and orientation in 6DOF. Small reflectors are used in combination with an infrared flash light for detection of light spots used as references. The diagram in C shows SNR versus subpixel precision for 90 light spots.

Figure 1. Prototype for A) 3DOF and B) 6DOF

Waheed Malik Dr. N. Lawal Xin Cheng [email protected] [email protected]


Optipos - Optical Position measurement in Real-time for Consumer Products



PROJECT INFORMATION – January, 2010 STC – Sensible Things that Communicate

Mid Sweden University Phone: 0771-975 000STC – Sensible Things that Communicates Fax: 060-14 84 56851 70 Sundsvall Internet: www.miun.se/stc

www.kks.se

DEVELOPMENT OF LOW-COST THERMAL DETECTOR FOR CO2 BASED INDOOR CLIMATE CONTROL

BackgroundThermal sensors for IR detection, such as bolometer and thermopiles are used in a number of applications. These applications include remote temperature control and gas detection. One step in the direction towards a low cost system is the use of a low cost infrared detector. ObjectivesThe goal of this research project has been to produce a low cost thermal detector using a combination of classic semiconductor materials and polymers.

The use of a CMOS compatible polymer, reduces the process complexity and thermal conductivity of the closed membrane structure, which increases the responsivity of the detector. Results

Using an iterative design optimization tool, an optimized detector design was developed and fabricated. The thermopile was characterized having a responsivity of 60 V/W and a thermal time constant of 70 ms. Using the NDIR method, the detector was also characterized in a CO2 detection application Iterative Design Optimization

Detector Fabrication

Detector Characterization

Detector Utilization

CO2 Detection Result

Development of Low-cost Thermal Detec-tor for CO2 Based Indoor climat control




Energy resolving X-ray imaging detectors

BackgroundWith a single photon processing X-ray imaging system, “colour” X-ray images can be achieved. The most advanced system existing so far is the Medpix system, Mid Sweden University is one of the partners designing this system, Medipix is an international research project directed from Cern in Geneva.

“Colour” X-ray imaging means that each pixel in the image contains spectroscopic X-ray energy information. Since the absorption coefficient for X-rays is materialdependent, material resolving X-ray imaging can be achieved.

ObjectivesA three bin representation for energy resolved X-ray images is demonstrated. The advantage with using three bin representations is that industrial video processing “knowhow” can be used. Hence a demonstrator setup might be possible to implement in industrial applications using existing video controlling mechanisms.

A test sample containing Tin, Gadolinium and Iodine is prepared. The materials in Table 1 are of interest in medical imaging where they can be used as contrast agents.

Table 1: Elements of test sample.Element Atom Kab (keV) Test sampleSn (Tin) 50 29.190 Tin with 3 % silver

I (Iodine) 53 33.164 Iodine powder

Gd (Gadolinium) 64 50.229 Scintillator Gd2O2S:Tb

ResultsThe image below is an energy resolved X-ray trans-mission image.

Fig 1 Left: Theoretical X-ray

image with uniform absorption. Without colour information the

image would be gray, but the test samples introduces energy

shifts in the image. Right: Image of a test object containing

Tin, Gadolinium and Iodine, the colour shows the Kab energy of

the object.

Examples of applications were material resolved X-ray imaging is interesting

• Wood-chip characterisation, online• Paper characterisation, online• Paper coating characterisation, online• Welding quality surveillance• General online manufacturing quality surveillance • Contrast agents identification in medical imaging• Dose reduction in medical imaging• Security surveillance

For further information contact: Börje [email protected]

060-148594

Sn

Gd

I

Tin

Gadolinium

Iodine



Development of Radiation HardPosition Detecting Devices

Background

Objective

Ongoing activities

www.miun.se www.tillvaxtvarket.se




Fast Measurement of Radon in buildings

BackgroundRadon is a gaseous isotope (222Rn) with a half-life of ~4 days. Its relative long decay time makes it possible to be released from the ground and contaminate the air in houses. Radon can also be released from building material, i.e. blue light concrete or gas concrete made of alum shale.

Inhaled Radon in lungs decomposes into 218Po and 214Po, which decay products, can cause lung-cancer. It is especially dangerous for smoker since radioactive particles can be stuck to particles in the smoke. Highest allowed concentration of Radon in buildings is 200 Bq/m3

(Sweden). WHO have suggested a decreased value to 100 Bq/m3 from the international standard of 1000 Bq/m3

Measurement of Radon concentration must be fast to verify the effect of remediation.

Measurement chamber

Fig. 1 Electrostatic forces transport the charged decay products to the detector for measurement. The filter limit the measurement to decay product decomposed inside the chamber, i.e. decay of Radon

Results

Fig. 2 Measurement of decay products, 218Po and 214Po

The two decay products of 222Rn are spectro-scopic resolved in the measurement

AcknowledgmentThe project is financed by Vinnova to develop a measurement platform. The project is collaboration between Mid Sweden University and Czech Technical University in Prague.


Göran Thungström

[email protected]

Phone: 060-14 88 05

filterdetector

Ra A’218Po

Ra C´214Po




Development of pixelated X-ray imaging sensors in silicon

BackgroundNew X-ray imaging devices use pixelated imaging sensors that are bump-bonded to a pixelated readout chip. In this way each photon that reaches each pixel can be processed separately. The most advanced system existing so far is the Medpix system, Mid Sweden University is one of the partners designing this system, Medipix(http://medipix.web.cern.ch/MEDIPIX/) is an international research project directed from Cern in Geneva.

Fig 1. Photo of a fabricated detector mounted on a circuit board from Cern.

Pixelated silicon sensors compatible with the MEDIPIX2 readout chip have been fabricated at Mid Sweden University. The sensors have a large pixel size of 220 µm to investigate the performance of a pixel detector with reduced charge sharing.

New sensor approachThe new sensor approach is to use n-type “channel stops” between the pixels and to use an n-doped dicing area. The voltage drop will in this case occur at the surface of the wafer as show from simulation. New masks with n-type channel stop and alternating guard rings have been fabricated. Different geometries were introduced to see the effect on reverse current and response.

Fig. 2. With p-type guard rings punch through effect extends

the field while an n-type guard ring effectively terminates the

field

Fig. 3. Layout of the modified sensor. Blue colour is p-type and green is n-type.

ResultsThe n-type channel stop effectively decreases the leakage current and the interpixel current of the detector. Further work will be done to develop methods to reduce the width of the guard ring and the space for dicing.


Göran Thungström

[email protected]

060-148805




High Frequency Switch Mode Power Supplies

BackgroundThe most essential unit required for all the electronic devices is the Power Supply Unit (PSU). It is required to design a compact Switch Mode Power Supply (SMPS) to make it compatible with the most modern electronic equipments. The continuous efforts on the improvement of the switching devices such as MOSFETS, diodes lead to the increased switching speeds of the power supplies. The switching devices working at higher frequencies reduces the size of passive elements such as capacitors, inductors and transformers which results in the compact size, weight, the increased power density of the converter and hence the high speed voltage regulation

ObjectivesThe goal of this project is to design and develop the highly energy efficient converter circuits operating in the high frequency range (MHz region) by using the Coreless PCB step-down Power Transformers developed in Mid Sweden University.

ResultsThe energy efficiency of the converter usingvarious transistors in the frequency range of 2.8-3.7MHz with the maximum output power of 35W is illustrated in fig.1. It can be observed that the Efficiency of the converter using SiC Mosfet is higher when compared to the other transistors.

Fig.2 Input Voltage vs. Energy Efficiency of the Converter

Ongoing activitiesCharacterizing the gate drive transformers designed for two switch flyback and half bridge converter circuits. Currently working on two switch flyback converter for improving the energy efficiency of the converter at higher frequencies


Hari Babu Kotte

[email protected]

Phone: 070-4738295




Development of disposable fiber-optical sensor technology in health-care applicationsBackgroundThe proposal for this project is related to development of new measurement technology and service functions in health care. The reason for this development is a complex mix between changes in human values, technology development, globalization, etc. Technology is one way to meet the rising health care cost in the modern society. And technology can provide new tools, that are more flexible and provide more freedom and quality values for service providers and service consumers.

ObjectivesThe idea is to use new fiber optic sensor technology for monitoring the health state of the patients, either in vivo or for sample taking. By using specialty fibers and new coatings technologies, we aim for better understanding of the limits and possibilities the combination of these technologies can give us. In the beginning we will aim at building an optical temperature and pH sensor in the physiological range.

Figure 1. Pentafiber

Ongoing activities2 prototype sensors have been built. These sensors consist of a Pentafiber (Fig 1) and a capillary tube together. Two versions of the probe are built. One that is welded and one where the pentafiber is tucked into a capillary tube (Fig 2).The idea is to fill the holes and the capillary tube, with Sol-Gel or Polymer that are doped with temperature and pH sensitive materials. At current stage we are doing some research on Sol-Gel, to find a Sol-Gel that have the right fluidic mechanics. And how to dry the Sol-Gel in the capillary tube without having errors in the dried Sol-Gel due to shrinking.

ResultsThe two different probes are built. And the next step is to characterize the probes.


Krister Hammarling

[email protected]

Phone: +46(0)60-148717

Figure 2. Pentafiber in a capillary tube. Pentafiber is in middle, and to the left in the picture.




Wireless VisualSensor Networks

IntroductionThe use of cameras as sensors in a sensor network introduces a whole range of new possibilities and challenges. New possibilities to:

• use machine vision in new places • optical positioning of people and things• remote reading of displays• surveillance of remote places

Camera based sensor networks will introduce a set of new challenges, as indicated in Figure 1:

• Low-power and low-energy real-time image processing architectures

• Intelligence partitioning

Figure 1. Wireless visual sensor network.

Architectures for imaging nodesIn previous research we have determined that FPGA technology show low-power and high performance for real-time image processing systems. In this project, we extend these studies to find architecture(s) that also show low energy behaviour as well.

Intelligence partitioningThe introduction of the high-performance sensor nodes introduces the design challenge of where to place the intelligence of the system, in the node or in some central computing server.

Analysis of magnetic particles in oil

A system for characterization of magnetic particle in oil is a system which requires wireless vision nodes. Figure 2 shows the lab setup for the optical measurement of magnetic particles. The developed image processing methods has been implemented on the 32-bit SENTIO platform and a VGA camera from Aptina. From the implementation we have estimated power consumption and timing of the different part according to the system model defined in Figure 3

Figure 3. System model for energy analysis of magnetic particle measurement system.

From the estimated values for the microcontroller implementation we see the system lifetime for the magnetic particle system for different measurement frequencies and how the energy is consumed for the different frequencies.

Figure 4. Battery life time vs. measurement frequency and relative energy consumption vs. measurement frequency.

For further information contact: Prof. Mattias O’Nils, [email protected]. Najeem Lawal, [email protected] MSc Khursheed, [email protected] Muhammad Imran, [email protected]

Intelligencepartitioning

Architecture for image processing

Figure 2. Magnetic particle measure-ment test setup.




High ResolutionElectron Detector

BackgroundRadiation describes any process in which energy that is emitted by one body travels through a medium or through space, ultimately to be absorbed by another body. These energies can be fathomed by devices that can interpret them in their various forms. The different radiation depending on their waveform ranges from X ray, ultraviolet rays (UV), gamma rays, thermal and even visible light.

Fig 1: Soft X-ray free-electron laser detector

ObjectivesThis project is primarily on the creation of a N+P detector and (at first) by way of simulation study not only various cost effective ways of developing high resolution detectors for low energy of electrons but also understanding the physics of electron radiation on silicon as well as improving the sensitivity and responsivity of the detectors.

Ongoing activitiesWith the help of Synopsys simulation package the n+p detector has been processed (figure 2) and simulated. What is now been investigated is with the use of another simulation software Geant4, the study of electrons radiation on the processed silicon detector. Geant4 is geometry and tracking platform for the simulation of the passage of particles through matter using Monte Carlo methods.

Fig 2: Sentaurus sprocess simulation of 5e15cm^3

doped phosphorus silicon implanted with arsenic

Fig 3: An image of a Geant4 simulated stark of silicon phantom

radiated with electrons

A goal of the simulation is to track the passage of a bombarding particle (electron in this case) through the detector. This involves considering possible interactions and decay processes. In addition, the detector response is recorded when the electron particle passes through the volume of the detector, - an approximating how a real detector would respond.


Omeime Xerviar Esebamen

[email protected]

076 211 4335




Stator-free Wireless RPM Sensor– A brand new way to measure rotor RPM !

AdvantagesNew!

RPM measurement that is not depend on stator side setup. The sensor package can be completely sealed.

Fast!Wide range (from 100 up to 100000 RPM) and

bandwidth (up to 100 kHz regardless of rotor RPM).The measurement rate and resolution are not limited by rotor gear number.

Accurate!Nonlinearity < 0.5%, SNR > 86 dB and the precision

increases with higher rotor RPM.

Small and light!Can be made very small (<2cm diameter), thin

(<1cm height) and light weight (<50gram) if mounted on one end of rotor shaft as a pad, or otherwise can be mounted as a ring around shaft.

Low cost!Based on commercial off-the-shelf electronic

components.

Wireless communication!RPM reading is sent out by RF signal, so data

receiver can be flexibly placed meters away from the sensor.

Wireless power!The power supply to the sensor can simply

come from stator side DC or AC magnetic field.

Potential customers Engine and transmission manufacturer

Motor and generator manufacturer

Process industry

Energy industry

Aerospace and military industry


Peng Cheng

[email protected]

Phone: 060148495




Printed Circuit Board (PCB) Transformers

BackgroundPower Supply Unit (PSU) plays a vital role in all the Electronic equipments. It is required to design a compact Switch Mode Power Supplies (SMPS) to make it compatible with the most modern Electronic equipments. As some of the applications demand multiple output and electrical isolation, the transformer became one of the irreplaceable components in the modern power supplies. The miniaturized SMPS is possible only with the increased switching frequency which in turn results in smaller passive elements, reduced cost and high speed voltage regulation.

At Mid Sweden University, various high frequency Coreless PCB transformers for power and signaltransfer applications were designed and the power transformers were evaluated for high power and at higher frequencies by using the Radio Frequency (RF) Power amplifier.

ObjectivesThe goal of this project is to develop several high frequency Coreless Printed Circuit Board (PCB) gate drive and power transformers for SMPS applications which are highly energy efficient and can be operated in MHz frequency region

ResultsA four layered 8:1 step down transformer was characterized by using the RF Power Amplifier for different load power ratings at an optimal

Fig.1 Load Power vs. Energy Efficiency of the Transformer

Operating frequency of 3.9MHz and are illustrated as shown in fig.1.Energy efficiency of the transformer is found to be in the range of 88-95%.

Ongoing activitiesDesigned the gate drive transformers required for the two switch flyback and half bridge converter circuits and evaluating their performance with sinusoidal excitations


Radhika Ambatipudi

[email protected]

Phone: 0761418934




Battery-less Operation of Wireless Sensor Networks using Solar Energy Harvesting

BackgroundDuring the the last years, power consumption of wireless sensor networks has been reduced tremendously. However, limited capacity of batteries still limits the lifetime of this promising technology.

In outdoor applications solar energy harvesting can help to reach “eternal” lifetime.

ArchitectureFig.1. depicts the architecture for a solar energy harvesting circuit developed at Mid Sweden University.

Light is converted to electricity using the photovoltaic effect, which then is stored in an electrochemical double layer capacitor providing energy to the attached sensor node

SimulationDue to the dependence on solar radiation, we developed a simulator for the proposed solar energy harvesting system. The simulator is based on real solar radiation data and estimates energy levels to the load and thus can predict time of no operation (Fig.2).

ExperimentInitial experiments have verified the functionality and accuracy of the simulator under artificial light conditions. A long time test in a network deployment is planned for further analysis of the system behaviour in the real environment.


Sebastian Bader

[email protected]

Phone: 060 148495

Fig. 1. Basic architecture of a battery-less solar energy harvesting system

Fig. 2. Simulation of operating time




MediaSense

BackgroundThe MediaSense project creates an open technology platform for the provision of distributed user and sensor information. The platform enables utilization of this information in multimedia service delivery and control across fixed andmobile heterogeneous broadband infrastructure.The project provides means for the acquisition of sensor and context information from mobile phones connected to 3G networks, portable computers connected to wireless broadband, and media centers in homes connected to fiber optic broadband.

ObjectivesHow we may interact with each other and the things that we use has been radically altered by the Internet. This is further fueled by the sharing and access to user and sensor information in mobile services and multimedia on the Internet.The objective of the MediaSense project is to understand the new possibilities for achieving things and rethink areas such as transport, journalism, archiving industrial processes, environmental sensing, context awareness, andonline collaboration. These challenges mandate studies not only of new models interacting with services and applications but also investigate in detail the necessary properties of systems, services and applications that utilize sensor and context information.

ResultsA seamless media-transfer prototype was shown at the STC Expo 2009. The prototype had the ability to transfer sessions to a mobile device,continuing the session without pause or video lag. The prototype enables a home server to transfer the media session from the home TV to the owner’s mobile device upon leaving the home.The prototype was also connected to a Zigbee sensor platform, which can both sense the environment, and control its surroundings using the built-in power socket actuator. The actuator controls a wall socket as an on/off switch, which enables remote power controlling. The Zigbee sensor has also been successfully integrated with Ericsson’s intelligent home media system.

Ongoing activitiesCurrent activities within the MediaSense project include an architecture that natively support sensor and context services, distributed context database objects, naming of globally addressablecontext, real-time aspects of context networks, and next generation context aware applications.


Prof. Theo Kanter

E-mail: [email protected]

Phone: 060-14 88 59





BackgroundThere is major interest in new functions for paper-based products, which can include intelligent drug packaging, talking in-store displays, packages with sensors that canindicate product shelf life over time and during shipment, printed images that can be animated, paper that can be used to connect to the Internet, and much more.

The objectives are find design and technology concepts to implement electronic functionalities on paper substrates.

In general, plastic substrates have been used for printed electronics, much because of the high requirements for very uniform and flat surfaces. However, the market and demand for printed electronics that can be manufactured on paper substrates is potentially very large. New functionalities, such as sensors, memory cards or indicators could then be integrated with traditional graphical products such as packages.

ObjectivesTo be able to print such functionalities successfully on paper based substrates there is important to understand the paper/ink interaction. The influence of the type of paper used has been shown to be substantial. Therefore an optimal paper substrate selection is critical for a specific applicationis important. In this project the interaction of the paper substrate and ink is investigated. The inks used are so called metal nano particle inks, where particles that are some tens on nano meter is mixed together with solvent to form a printable substance. After printing these particles have to be melt together to have a good conductivity, so called sintering. Because of their small size,the particles have a much lower melting temperature than the bulk metal, so silver nano particles can give a good conductivity even at such a low temperature as 100°C, a temperature that paper can withstand without problems.

Much of the research have has been directed towards integration of a specific nano-particle based printed modulator device called WORM, see Figure 1.

Figure 1. Photo of WORM device, where the thin line between the contacts are the actual WORM and has a length of 125µm.

The WORM device is actually an electrically programmable memory that can change its internal resistance by several orders of magnitude depending on applied power. We have also found that such WORM devices can be design to trigger by humidity or temperature which opens up for possible sensor functionalities.

ResultsThe nano ink/paper studies have shown interesting connections between the behaviour of the printed WORMs and the paper substrate used. Investigations is ongoing, but for example the stability of WORM memories have been investigated. The graph in Figure 5 show the resistance drop over time in normal Swedish summer climate.

Figure 2. Graph showing how the resistance of WORM memories drop over time, it can be seen that the change is upto 7% over a period of 14 days.

Figure 3. AFM picture showing prinetd silver nano particles, the size of each particle is in the range of 50-100nm.


Dr. Henrik Andersson

[email protected]

Phone: +46 70 3622245





Inkjet Printed WORM Memory Card Reader

BackgroundMemory cards have been manufactured by ink jet printing of silver nano ink on photo paper. In addition, a compact memory card reader for PC has been constructed, see Figure 1. This makes for a complete system of printed memory cards and inexpensive readers that can be used for various applications.

The memory cards each have 8 memory cells and have the same physical layout as Secure Digital cards, left part in Figure 2. The memories can be programmed to specific values representing the data on the cards, so called Write Once Read Many (WORM) memories. The memory card reader measures the resistance values of the WORMS and reads it back to the PC by USB connection.

Figure 1. Photo of memory card reader.

ResultsThe application of such a system of low cost printable memory cards can be many, for example the information on the cards can be connected to personalized information on the internet, so that when the card is inserted in the reader a personalized webpage is automatically displayed. The memory cards are manufactured by ink jet printing silver nano particle ink on photo paper by a Dimatix materials printer, see right part in Figure 2 for a photo of a magnified memory structure.

By using multiple resistance states of the memory, the possible combinations increases from 256 if two states is used to 6561 with three states and 65536 with four statesand so on.

Figure 2. Photo of memory, left and magnified memory structure, right.

The number of possible states is related to the resolution of the reader and the stability of the WORM memory. The memories in this article are programmed to 10kΩ, 6kΩ or 2kΩ- The reader that was constructed can resolve 50Ω, in the range of 0-10kΩ so it is mostly how well the memories can be programmed and the stability that sets the limit for how many states that can be used.

In Figure 3 is shown a screen capture of the card reader demo software developed in Labview.

Figure 3. Screen capture of the reader software.


Dr. Henrik Andersson

[email protected]

Phone: +46 70 3622245




Printed RFID SensorsBackgroundAs the number of wireless sensors are increasing exponentially around us they typically suffer from two major drawbacks; cost and battery lifetime. This project focuses on utilizing existing RFID chips and new printing technologies to overcome these limitations in order to provide sensor solutions to areas where it previously has not been affordable or technically practical. Application examples rangefrom detection of high humidity values inside house walls to telling whether a transported package has been exposed to wetness or too high temperature. The research is conducted in collaboration with the projects Paper Four and PriMeBits and in close collaboration with the company Sensible Solutions Sweden AB.

ObjectivesThe objectives are to utilize two or more ordinary RFID chips, incorporated into the same RFID label but with individual antennas for each chip where one antenna is ‘normal’ and the other antennas comprise different sensors that change the antenna properties in accordance to the physical quantity they are designed to detect. A concept with differential measurements of the tags activation energies is a promising way of retrieving information of such sensors. In addition to present values the objective is also to tell whether a certain sensor value has occurred earlier in time, i.e. a memory effect.

ResultsThree different sensor setups have so far been demonstrated using innovative printing- and paper technology. The first solution takes advantage of laminating a paper material specially designed to absorb moisture next to a printed RFID antenna, allowing an intelligent RFID readout protocol to retrieve information of the moisture value at the location of the sensor label. Second and third demonstrated solutions uses a specific nano-particle based printed modulator device called WORM that are integrated as modulators in RFID antennas and tells whether a high temperature or humidity value has ever occurred.

Ongoing activitiesTwo main activities are currently taking place. One focuses on intelligent and fast readout algorithms for handheld RFID readers. The other investigates how to combine three or more sensor tags into the same label in order to combine different sensor properties, for example both present and historical values.


Name: Jinlan Gao

E-mail [email protected]

Phone: 076 400 09 66




Connecting mobile services

BackgroundThe proliferation of mobile sensor-based services mandate research regarding support for the utilization of sensor and context information from mobile phones connected to 3G networks, portable computers connected to wireless broadband, and media centers in homes connected to fiber optic broadband. Such services require an open technology platform for the provision of distributed user and sensor information. The platform should support scalable utilization of this information in sensor based multimedia service across fixed and mobile heterogeneous broadband infrastructure.

ObjectivesConnecting to resources today requires extensive configuration of the device itself as well as any intermediate devices and access to these devices is mostly limited to the local network. The goal of the research project is to investigate the possibility to create support for a globally unique namespaceto which devices can attach to and communicate with other devices. This support would enable users to access their devices regardless of their current location.

ResultsBy separating identity from location a new layer of indirection is created which is collocated with the novel support for context exchange created within the MediaSense project. Adding a new layer enables client applications to base their connectivity on a new context namespace independent of today’s DNS and IP addresses. This renders knowledge about devices location and means of connection superfluous for applications. This does not remove the possibility to associate devices with a location if an application calls for it but such location would be more descriptive than a DNS name or IP address.

Current activitiesCurrently a proof of concept is being developed that enables the use of a networked printer regardless of the user’s location both within and outside of the local area network where the printer resides.


Victor Kardeby

E-mail:[email protected]

Phone:060-14 85 74





Scalable and Searchable

Real-time Context Exchange

Background With the development of rich mobile devices such

as the Google android, the need for applications

which change their behavior based on the user’s

context is demanded. Such intelligent applications

are called context aware applications and this

research is about enabling these applications.

Objectives Context aware applications need to access the

context of both the user and also the context of

the user’s friends and people related to the user.

This mandates the use of distributed architectures

to administer the exchange of context information.

This research’s objective is to create such a

“Context Network”, and to enable scalable

applications which can provide real-time services.

The larges problem in context aware applications

is the immediacy of information, which means that

context information is required to accessible

everywhere, and should be acquired without

delay. There is also a large secondary problem,

the need to be able to perform complex queries in

regards to context. For example, one would like to

know: “The status of all people that are in front of

me, travelling in the same direction, and has the

same interests”. To answer such a query reliably,

complete knowledge about all people in the whole

world is required, which is not a possibility in

current architecture.

Results Initial results include architectures supporting

context exchange in real-time, such as protocols

using Distributed Hash Tables, and also ad hoc

grouping protocols. But also many proof of

concept applications, including context ware

applications on Google Android, home computers,

and even low end mobile devices using the Java

ME platform.

Ongoing activities Current activities within this research include

extensions to previous architectures to solve the

search problem and the dynamics of evolving

context.


Stefan Forsström

[email protected]

Phone: 070-6084796

Context




Distributed Object Models in Support of Context

Oriented Applications and Services

BackgroundMultimedia coupled with sensor-based services

over heterogeneous networks mandate research

in support of the notion that distributed

infrastructures provide the most scalable and

reliable means of exchanging context information

supporting the Internet of things. Other research

into linked data and knowledge discovery inspires

the need to create scalable intelligent

architectures for enabling context dependent

applications and services. The existing

MediaSense research provides the ideal

foundation for further exploration in this direction.

ObjectivesDynamic entities require robust infrastructures

underpinning interaction and service delivery

reflecting the continual changes in context.

Architectures that distribute and utilize the

supporting sensor information within the

constraints of traditional publish-subscribe

systems provide sensor information in primitive

forms requiring extensive application level

transformations limiting the dynamic addition and

removal of sources. By applying ontological

representations to sensors elevated as first class

objects in a distributed meta-model, we provide

for a real-time linked-data solution improving on

traditional implementations. Further, by providing

for object schemata underpinning presentities and

with schemata which are continually evolving over

sensor domains, we always represent an accurate

temporal view of a user's context and by

extension a user's presence with respect to the

available sensors and actuators.

Further implications of such real-time knowledge

lies in the ability to create real-time indexable and

distributed searches, real-time applications

delivering multimedia and the discovery of

resources available to users.

ResultsEarlier results include the implementation of

distributed frameworks in support of real-time

context exchange. Further examination of this

approach and the previously implemented

centralized solution has been undertaken

establishing a clear path forward for the

distributed approach. Continual research within

MediaSense has evolved services and

applications which highlight the importance of

such a research direction.

Ongoing activitiesWe have created object based presence profiles,

seamless media-transfer services and are looking

at object-oriented persistence on mobile devices

as well as presence aggregation and translation.

Further work will solidify an implementation over

these collective solutions.


Jamie Walters MSc.(Lon)

[email protected] Phone: 060-14 87 16



Scalable and Searchable

Real-time Context Exchange

Background With the development of rich mobile devices such

as the Google android, the need for applications

which change their behavior based on the user’s

context is demanded. Such intelligent applications

are called context aware applications and this

research is about enabling these applications.

Objectives Context aware applications need to access the

context of both the user and also the context of

the user’s friends and people related to the user.

This mandates the use of distributed architectures

to administer the exchange of context information.

This research’s objective is to create such a

“Context Network”, and to enable scalable

applications which can provide real-time services.

The larges problem in context aware applications

is the immediacy of information, which means that

context information is required to accessible

everywhere, and should be acquired without

delay. There is also a large secondary problem,

the need to be able to perform complex queries in

regards to context. For example, one would like to

know: “The status of all people that are in front of

me, travelling in the same direction, and has the

same interests”. To answer such a query reliably,

complete knowledge about all people in the whole

world is required, which is not a possibility in

current architecture.

Results Initial results include architectures supporting

context exchange in real-time, such as protocols

using Distributed Hash Tables, and also ad hoc

grouping protocols. But also many proof of

concept applications, including context ware

applications on Google Android, home computers,

and even low end mobile devices using the Java

ME platform.

Ongoing activities Current activities within this research include

extensions to previous architectures to solve the

search problem and the dynamics of evolving

context.


Stefan Forsström

[email protected]

Phone: 070-6084796

Context

Distributed Object Models in Support of Context Oriented Applications

and Services


A research program at Mid Sweden University, sponsored by The Knowledge Foundation, in partnership with:

iberson

SenseAir ®

Adal AB

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