introduction to civil engineering...

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Introduction to Civil Engineering Systems

LECTURELECTURE

What is a System?What is a System?

Sam LabiSam LabiPurdue University, West Lafayette, IndianaPurdue University, West Lafayette, Indiana

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Topics for today’s conversation

System? What the System? What the …… is that?is that?

General and Specific Examples of Systems in General and Specific Examples of Systems in Everyday Life and in CEEveryday Life and in CE

Attributes of a SystemAttributes of a System

Examples of CE Systems and their attributesExamples of CE Systems and their attributes

Challenges faced by Civil Systems EngineersChallenges faced by Civil Systems Engineers

Steps for Systems DevelopmentSteps for Systems Development

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WHAT’S A SYSTEM?

How do we define a System? How do we define a System?

Etymology: Etymology: From Late Latin From Late Latin

systematsystemat--, , systemasystemaFrom Greek From Greek

systEmatsystEmat--, , systEmasystEma, , from from synistanaisynistanai ((to combine), to combine), from from synsyn-- + + histanaihistanai ((to cause to stand)to cause to stand)

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WHAT’S A SYSTEM?

MerriamMerriam--WebsterWebster’’s definitions definition““a regularly interacting or interdependent a regularly interacting or interdependent

group of items forming a unified whole.group of items forming a unified whole.””

Other definitionOther definition““A collection of interrelated objects, rules or A collection of interrelated objects, rules or

procedures that interact to achieve a procedures that interact to achieve a certain goalcertain goal””

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General Examples of SystemsGeneral Examples of Systems

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WHAT’S A SYSTEM?

General Examples:General Examples:

1. a group of devices or artificial objects or 1. a group of devices or artificial objects or an organization forming a network an organization forming a network especially for distributing something or especially for distributing something or serving a common purpose serving a common purpose

2. an organized set of doctrines, ideas, or 2. an organized set of doctrines, ideas, or principles usually intended to explain the principles usually intended to explain the arrangement or working of a whole entityarrangement or working of a whole entity

3. an organized or established procedure 3. an organized or established procedure

4. a harmonious arrangement or pattern4. a harmonious arrangement or pattern

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WHAT’S A SYSTEM?

Specific Examples of SystemsSpecific Examples of Systems

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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life: Specific Examples of Systems In Everyday Life: The Human Body (Yeah, You!)The Human Body (Yeah, You!)

-- Consists of various organs that work together Consists of various organs that work together to achieve various goals including to achieve various goals including ……

…… moving from place to place,moving from place to place,…… learning and working for a livinglearning and working for a living…… staying alive, etc.staying alive, etc.

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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:

Computer Hardware SystemComputer Hardware SystemThe CPR, Monitor, and KeyboardThe CPR, Monitor, and Keyboard

(note: this is a physical system)(note: this is a physical system)

Clip art images of computer components removed due to copyright restrictions.

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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Specific Examples of Systems In Everyday Life:Life:

Computer Operating SystemComputer Operating System

A set of sequential rules and algorithms A set of sequential rules and algorithms (written using computer code or machine (written using computer code or machine language) that govern the way the language) that govern the way the computer runs. computer runs.

Example: Disk Operating System (DOS)Example: Disk Operating System (DOS)Windows Windows ‘‘9898

(note: this is an operational system)(note: this is an operational system)

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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:Sports Stadium SystemSports Stadium System


-- Steel Columns

-- Steel Beams

-- Seats

-- Playing Field

-- Press Box

-- Scoreboard, etc

Image of stadium removed due to copyright restrictions.

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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:Rules of Operation for the Sports StadiumRules of Operation for the Sports Stadium

Entry/Exit SystemEntry/Exit System-- Certain rows enter or exit Certain rows enter or exit the stadium before others.the stadium before others.

Behavioral SystemBehavioral System-- No throwing of beer No throwing of beer cans, vandalism prohibited, etc.cans, vandalism prohibited, etc.

No spectators allowed on field during play.No spectators allowed on field during play.

Rules of Game to be followed by all players.Rules of Game to be followed by all players.


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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:

A UniversityA University’’s Physical Facilities Systems Physical Facilities System


-- Roads/Streets

-- Buildings

-- Sidewalks

-- Landscape

-- Utility lines

-- Fountains, etc

Photograph removed due to copyright restrictions.

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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:MITMIT’’s GPA Scoring Systems GPA Scoring System

GPA Scoring:GPA Scoring:Set of RulesSet of RulesA A Computational FormulaComputational Formula usedused

-- depends on the depends on the credit hourscredit hours of each of each course takencourse taken-- also depends on also depends on grade earnedgrade earned for for each courseeach course


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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:MIT Credit Union Bank Structure and MIT Credit Union Bank Structure and

Facilities SystemFacilities System


-- Counters

-- Computers

-- Cash counting machines

-- Safes and Vaults

-- Security Cameras

-- Accounting books, etc

-- Utilities

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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:MIT Credit Union Loan Application SystemMIT Credit Union Loan Application System

Set of Rules for Loan ApprovalSet of Rules for Loan Approval-- Credit History,Credit History,-- Amount to be borrowed,Amount to be borrowed,-- Outstanding loan balances, etc.Outstanding loan balances, etc.

All these are entered into a formula which spits out All these are entered into a formula which spits out a decision on whether to accept or to reject the a decision on whether to accept or to reject the loan applicationloan application


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WHAT’S A SYSTEM?

Specific Examples of Systems In Everyday Life:Specific Examples of Systems In Everyday Life:Queuing System at BMV, McDonalds, etc.Queuing System at BMV, McDonalds, etc.


SOME OPERATIONAL RULES

-- Enter from the back of Queue, not the front

-- Stand in a straight line

-- Proceed to the front of the queue and not towards the back

-- Leave the queue after you are served

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WHAT’S A SYSTEM?

Specific Examples of Systems In Civil Engineering:Specific Examples of Systems In Civil Engineering:Traffic Signal System (Equipment)Traffic Signal System (Equipment)


-- Metal Poles

-- Light Bulbs

-- Electrical Wiring

-- Signs

-- Processor

-- Loop Detectors in Pavement, etc

Photograph removed due to copyright restrictions.

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WHAT’S A SYSTEM?

Specific Examples of Systems In Civil Engineering: Specific Examples of Systems In Civil Engineering: Traffic Signal System (Timing Sequence)Traffic Signal System (Timing Sequence)


TIMING SEQUENCE (Example)

1. Main Street

Green – 17 seconds Yellow – 3 secondsRed – 10 seconds

2. Side StreetGreen – 10 seconds Yellow – 3 seconds Red – 17 seconds

3. Additional All Red Time for both Streets– 3 seconds

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WHAT’S A SYSTEM?Specific Examples of Systems In Civil Engineering: Specific Examples of Systems In Civil Engineering:

A System of Construction Activity Sequence and A System of Construction Activity Sequence and Schedules (such as the Critical Path Method)Schedules (such as the Critical Path Method)

-- Do some activities Do some activities ………… before certain others, before certain others, …… after certain othersafter certain others…… simultaneously with certain otherssimultaneously with certain others

-- Choose the best sequence of activities that Choose the best sequence of activities that ………… minimizes time delayminimizes time delay…… is consistent with supply schedulesis consistent with supply schedules…… does not compromise the budgetdoes not compromise the budget…… is within labor constraints, etc.is within labor constraints, etc.


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WHAT’S A SYSTEM?

Specific Examples of Systems In Civil Engineering:Specific Examples of Systems In Civil Engineering:

A Sedimentation Pond (Physical Structure)A Sedimentation Pond (Physical Structure)

PondPondLinerLinerPumps, Pumps, Pipes, etc.Pipes, etc.


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WHAT’S A SYSTEM?

Specific Examples of Systems In Civil Engineering: Specific Examples of Systems In Civil Engineering: A DecisionA Decision--Support System for Sewer Pipe Support System for Sewer Pipe

ReplacementReplacement

Hypothetical example of some decision Hypothetical example of some decision parameters:parameters:

-- When pipe age exceeds 50 yearsWhen pipe age exceeds 50 years-- If slope exceeds 5%If slope exceeds 5%-- If demand exceeds pipe capacityIf demand exceeds pipe capacity-- if sewer condition (corrosion levels) are if sewer condition (corrosion levels) are

found to be very high , etc.found to be very high , etc.

(note: this DSS is an operational system)(note: this DSS is an operational system)

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WHAT’S A SYSTEM?

Specific Examples of Systems : Specific Examples of Systems :

The Rest Room The Rest Room ““SystemSystem””


KeyboardKeyboard

Occasional Occasional MonitorMonitor

Software UnitsSoftware Units

Central Central Processing Processing

UnitUnit

MouseMouse

Floppy DiskFloppy Disk

Sound Sound KnobKnob

(Stereo)(Stereo)

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WHAT’S A SYSTEM?

Attributes of a system:

1. Physical structure

2. Rules or procedures for operation of the system

3. Goals or objectives

4. Criteria by which attainment of the goals are measured (MOE’s)

5. Condition or performance of the system at any time

6. Environment within which system operates

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WHAT’S A SYSTEM?

Components of a system:These typically refer only to the following attributes:

- Physical Structure

- Operating procedures/rules

Note:

Not all systems have a physical structure component.

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WHAT’S A SYSTEM?

Examples of CE Systems and AttributesExamples of CE Systems and AttributesSystemSystem Physical Physical

Structure(s)Structure(s)OperationOperation GoalsGoals Performance Performance

CriteriaCriteriaInterstate 90 Interstate 90 Freeway Freeway System,System,

PavementPavementRoad SignsRoad SignsBridgesBridges

Vehicular Vehicular useuse

Improve Improve traffic flowtraffic flow

Congestion Congestion levelslevels

Traffic Signal Traffic Signal SystemSystem

Traffic Lights,Traffic Lights,Video Video CamerasCameras

Vehicular & Vehicular & pedestrian pedestrian useuse

Minimize Minimize delaydelay

Average Average delay per delay per vehicle and vehicle and pedestrianpedestrian

Freeway Freeway PatrolsPatrols

Vans, 2Vans, 2--way way radios, Tow radios, Tow cranescranes

Patrolling Patrolling the the highwayhighway

Quickly clear Quickly clear accidentsaccidents

Accident Accident response & response & clearance clearance time, minutestime, minutes

Boston Waste Boston Waste Treatment Treatment SystemSystem

Filtration Units, Filtration Units, Sedimentation Sedimentation ponds, etc.ponds, etc.

Effluent Effluent TreatmentTreatment

Maximize Maximize amt. of waste amt. of waste treatedtreated

Volume of Volume of waste treated waste treated /hr/hr

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WHAT’S A SYSTEM?

Some General Categories of CE SystemsSome General Categories of CE Systems

Physical vs. OperationalPhysical vs. Operational

Dynamic vs. StaticDynamic vs. Static

Network vs. NonNetwork vs. Non--networknetwork

SupersystemSupersystem vs. Subsystemvs. Subsystem

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Questions that systems design seeks to answer:

Obviously, CE system design can be Obviously, CE system design can be aa daunting taskdaunting task ……

WHETHER?

WHY?HOW?

WHAT?

WHAT?WHICH?

WHAT?

WHEN?

WHEN?

WHEN?

WHY?

WHY?

WHEN?WHEN?

HOW?

HOW?WHAT IF?

WHEN?

WHEN?

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WHAT’S A SYSTEM?

Examples of such questions:Examples of such questions:Is the physical structure of IIs the physical structure of I--90 adequate for the kinds of 90 adequate for the kinds of

trucks that use that highway?trucks that use that highway?

How can we describe highway traffic operations on How can we describe highway traffic operations on PurduePurdue’’s State Street?s State Street?

Is the level of congestion on IIs the level of congestion on I--93 tolerable?93 tolerable?

How can we minimize delay at our local intersections?How can we minimize delay at our local intersections?

Is it OK to use a new cheaper lightweight material for our Is it OK to use a new cheaper lightweight material for our steel structures?steel structures?

What factors affect our decision to design a new water What factors affect our decision to design a new water treatment plant for our fast growing city?treatment plant for our fast growing city?

How can we optimize the operations of our waste How can we optimize the operations of our waste treatment plant?treatment plant?

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Examples of such questions (continued):Examples of such questions (continued):

Why do we choose a concrete pavement over an asphalt Why do we choose a concrete pavement over an asphalt pavement for a specific project?pavement for a specific project?

When should we replace a bridge deck?When should we replace a bridge deck?

Whether or not to line a large sedimentation pond.Whether or not to line a large sedimentation pond.

How to describe the way PurdueHow to describe the way Purdue’’s Loop Transit works.s Loop Transit works.

What economic conditions make it more attractive to build a What economic conditions make it more attractive to build a highway in 2005 instead of now?highway in 2005 instead of now?

How to predict the condition of a steel bridge elements 10 How to predict the condition of a steel bridge elements 10 years from now?years from now?

What factors to consider in designing a parking garage for What factors to consider in designing a parking garage for Purdue?Purdue?

WHAT’S A SYSTEM?

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WHAT’S A SYSTEM?

Therefore, all engineers face the challenge of:

Planning and managing our systems effectively: we as engineers should obviously be able to carry out effective …

(1) Systems description,(2) Systems analysis,(3) Systems optimization,(4) Systems evaluation, and(5) Systems selection (for more than one

alternative).

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WHAT’S A SYSTEM?

SYSTEMS DESIGN

Physical design: What physical design should I use for the new facility?What physical modifications should I make to an existing system?

Operational design: What rules or procedures should govern the operation of my new system?What changes in operational rules and procedures are needed to my existing system?

The challenges that all engineers face (continued):

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WHAT’S A SYSTEM?

SYSTEMS DESCRIPTION

Description of physical structure: How can I describe the composition or physical structure of my design? Graphically? Blue Prints, Artistic sketches? If the structure changes over time, can I predict the future physical structure say, 10 years from now?How should I describe proposed physical modifications to an existing structure?

Description of Operational Procedures: How should I describe the way the system works? An equation? Probability distributions? Graphical simulation?How should I describe proposed changes in the operations of the system?

Description of System Condition: How can I describe the condition of the system? Using GIS?How can I predict the future condition of the system? Using statistical models?


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WHAT’S A SYSTEM?

SYSTEMS ANALYSIS

Analysis of the Physical Structure:

How do we calculate to get the engineering features of each member of the system. E.g., what are the shear forces and bending moments in each member of a steel truss?

Analysis of the System’s Operational Procedures: How does the system work? How are loads supported?

How is the effluent treated?


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WHAT’S A SYSTEM?

SYSTEMS OPTIMIZATION

Optimization of Physical Structure: What physical design gives me the highest benefits at least possible costs of construction and maintenance of the physical structure?

Description of Operational Procedures: How should I operate my system in order to yield the most benefits with minimal costs?


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WHAT’S A SYSTEM?

SYSTEMS EVALUATION

Evaluation of physical structure: Is the system structurally sound?Are bending moments and deflections acceptable?Is the system physical condition OK?

Evaluation of Operational Procedures: Are the system goals being achieved?Is there a more economical way to operate the system?What is the ratio of the system benefits to its costs?Are there any environmental side effects of system operation?

Evaluation of System Condition: Five years from now, will the expected condition be acceptable?level of cracks can we expect on the system structure 5 years from now?


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WHAT’S A SYSTEM?

SYSTEMS SELECTION (only where we are choosing one of many alternative designs for a system)

Selection of Best Physical Structure: On what basis should I say a particular physical design alternative is the best?

- Aesthetics? - Maintainability?- Environmental compatibility? Etc.

Selection of Best Operational Procedure: On what basis should I say a particular operational design alternative is the best?

- Availability of skilled operating personnel? - Harmony of operations with the environment? Etc.


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WHAT’S A SYSTEM?

Summary of the challenges we civil engineers face …

Design, Optimize Physical Structure

Describe, Predict Condition

Analyze, Evaluate Operation/Usage

Activities for the Systems Designer

System Attributes

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WHAT’S A SYSTEM?

Therefore, …The overall steps in systems development are:

SYSTEMSDESIGN

SYSTEMSDESCRIPTION

SYSTEMSANALYSIS

SYSTEMSEVALUATION

SYSTEMSSELECTION

SYSTEMS OPTIMIZATION

- PHYS. STRCT.- OPS/USAGE

- PHYS. STRCT.- CONDITION- OPS/USAGE



- PHYS. STRCT.- OPS/USAGE

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The Last Word The Last Word ……

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The Last Words for Today

Key questions for the systems engineerKey questions for the systems engineer

1. How should I design my system? What factors to consider in 1. How should I design my system? What factors to consider in the design?the design? What steps should I follow?What steps should I follow?

2. How can I best describe (or predict in future) the physical 2. How can I best describe (or predict in future) the physical structure, condition or performance of the system to any structure, condition or performance of the system to any interested party?interested party?

3. How do I choose from several alternative systems? What 3. How do I choose from several alternative systems? What factors should I consider?factors should I consider?

4. How can I tell if a given system is doing well? 4. How can I tell if a given system is doing well?

5. How can I optimize the operations of my system? What 5. How can I optimize the operations of my system? What should I minimize? What should I maximize?should I minimize? What should I maximize?

*Tools include Math, Econ, probability, statistics, operations research, etc.

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