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Page 1: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

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DOI-Status changed to Fault-Detected

4.72.4.5

T

TPrev(Altitude) = At-or-above-threshold

Altitude = Below-threshhold

State Values DOI-Status = On F

Output Command

DOI-Power-On

high (on)

DOIDestination:

Acceptable Values:

Initiation Delay:

Completion Deadline:

Exception-Handling:

Feedback Information:

Variables:

Values:

Relationship:

Min. time (latency):

Max. time:

Exception Handling:

Reversed By:

Comments:

Turned off by some other component or components. Do not know which ones.

Should be on if ASW sent signal to turn on

DOI-status-signal

50 milliseconds

0 milliseconds

{high}

2 seconds

4 seconds

TRIGGERING CONDITION

CONTENTS

= discrete signal on line PWR set to high

Operating Mode TOperational

Not Inhibited T

References:

¸¹]ºW»_¼�½�¾_¿ÁÀ(Â�ÃÅÄÇÆ�È]½�ÉÅÊ(ÃÅËÍÌ�»�ÎÏÆ_»ÐÎ�ÑGÆÒ½�Ó�¹·Ô_Ó�Ã;Î6¹]ÉWËÕÅÖ

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éPÜ_½wÛ�ÆÒ½�Ó�¹·Ô_Ó�Ã;Î6¹]ÉWËÍÉÅÊ4Ó�ÉÅËVÎ6¼6ÉWÈRÃÅË�×ç×_¹]Û�Æ_ÈTÃ�ß�¹·Ë_Æ_»�Î6Û)ÃÅË�×çÉW»�Î6Æ_»�ÎÏÛ)Ãż6½*Û6¹·Äǹ·ÈTÃż�Î6É๷Ë_Æ_»�Î6ÛÃÅË_×*ÉW»�Î6Æ_»�ÎÏÛOÊ©¼6ÉÅÄ ÎÏÜ_½ÁÓ�ÉÅËVÎ6¼6ÉWÈ·È]½�×ÝÆ�¼6ÉGÓ�½�Û�Û�áaéPÜ�½%ºW½�Ë_½�¼6ÃÅÈ:Ê©ÉW¼6Ä�ÛRÃż6½�Û�Ü_Éåê�Ëw¹]Ë�ÎÏÜ_½%ÃÅÆ_Æ+½�Ë�×_¹æÂÃÅË_×ÍÃÅË�½ïÂ�ÃÅÄ�Æ_È·½�¹]Ë�¸(¹·ºW»_¼6½&%Ðá('�Ë�ÎÏÜ_½�½eÂ_Ã;ÄÇÆ_È·½Åî�Î6Ü_½�×_½�Ô_Ë_¹·Î6¹]ÉWË�½�Û6Û6½�Ë:ÎϹTÃ;È]È·ßàÛÏÃ�ßGÛóÎ6ÜUÃ;Î�ÎÏÜ�½ä;ÃÅÈ]»�½4Ó�ÉWÄ�½�ÛOÊ©¼6ÉWÄ ÎÏÜ_½*)��+#�,-#/.�01!QÔU½�È]×ݹ]Ë�ÎÏÜ�½32547698XÄǽ�Û6Û6ÃźW½ÁÃÅË_×ݹ]ÛOÃÅÛ�Û6¹·ºWË_½�×Ýê�Ü_½�Ë/ÃPÄǽ�Û6ÛÏÃ;ºW½Ãż�¼6¹·äŽ�Û�á('XÊQË_É*Äǽ�Û6ÛÏÃ;ºW½)ÜUÃ;Û�Ãż�¼6¹æäW½�×ǹ]ËØÎÏÜ_½YÆUÃÅÛ�Î Õ Û6½�Ó�ÉWË_×�Û�î�Î6Ü_½YÆ�¼6½�äG¹·ÉW»_Û%ä;ÃÅÈ·»_½�¹]ÛÁ»_Û6½�×Qá('XÊÎÏÜ�½�ÈTÃÅÛ�Î�Ä�½�Û6Û6ÃźW½�Ã;¼6¼6¹æäW½�×�ÄÇÉW¼�½)ÎÏÜ_ÃÅË Õ Û6½�Ó�ÉWË_×�ÛóÙ+½�Ê©Éż6½ÅîGÎÏÜ_½�×_Ã;ÎÞÃ/¹·Û�Ó�ÉÅË_Û6¹·×_½�¼�½�×�ÉWÙ_Û�ÉWÈ]½ïÎϽÅáéPÜ_½&¹·Ë_Æ_»�Î/äÅÃ;¼6¹TÃ;Ù_È]½�ÃÅÈ·Û6ÉçÛ�ÎÞÃż�ÎÏÛ/ê�¹æÎÏÜIÎ6Ü_½&ÉWÙ_Û�ÉWÈ]½ïÎϽçðS»_Ë_×�½�ÔUË_½�×8ñ/ä;ÃÅÈ]»_½;á;:�½�Ó�ÃÅ»�Û6½�ÉÅÊ�ÎÏÜ�½Û6¹·Äǹ·ÈTÃż�¹·Î�ß�ÉÅÊÎÏÜ_½�Ê©ÉW¼6ÄôÉ;ÊaÄ�ÉWÛ�Îó¹]Ë�Æ_»�Îó×_½�Ô_Ë_¹·Î6¹]ÉWË_Û�îUê�½*ÄàÃ�ß�Û�¹]Ä�Æ_È]¹æÊ�ßÇÎ6Ü_½*Ë�ÉÅÎÞÃ;Î6¹]ÉWË ¹]Ë�ÎÏÜ�½Ê©»�Î6»_¼6½;á

Ñл_Æ+½�¼�äй·Û6ÉW¼�ß ÄÇÉG×_½�Û�ÄÇÃ�ß�Ë_½�½�×ÍÎÏÉÇÙÒ½�Û�ÆÒ½�Ó�¹·Ô_½�×[Ê©ÉW¼�¹·Ë_Æ_»�Î�ä;ÃÅÈ]»�½�Û�ÎÏÉ�×_½�Î6½�¼6Ä�¹]Ë�½�ê�Ü�¹]ÓÞܹ]Ë�Æ_»�ÎÏÛPÎ6É�»�Û6½ÝÃ;ÎYÃÅË:ß&ÎϹ·Äǽ;á

õQöS÷8ö·õ <ªþ��Ðþ��[ÿ=��� �����>��? ����(û��þ@���ÒûÑGÎÏÃ;ÎϽ�ä;Ãż6¹]ÃÅÙ_È·½àä;ÃÅÈ]»_½�ÛØÃż6½�¹·Ë�Ê©½�¼�¼6½�×sÊ©¼�ÉWÄ Î6Ü_½�äÅÃ;È]»_½�Û�É;Ê)¹·Ë_Æ_»�Îãä;Ãż�¹TÃÅÙ_È·½�ÛwÉżwÊ©¼6ÉWÄ É;ÎÏÜ_½�¼Û�ÎÏÃ;ÎϽ�ä;Ãż6¹]ÃÅÙ_È·½�ä;ÃÅÈ·»_½�Û�á4¸(¹·ºW»_¼6½�AÝÛ6Ü_Éåê�Û�ÃÝÆUÃż�ÎϹTÃ;ÈU½ïÂ�ÃÅÄ�Æ_È]½�ÉÅÊOÃÝÛ�ÎÏÃ;ÎϽ�ä;Ãż6¹]ÃÅÙ_È]½P×�½�Û6Ó�¼6¹·Æ�ÎϹ·ÉWËÊ©ÉW¼�Î6Ü_½ÝÃÅÈ·Î6¹·ÎÏ»�×_½�Û�ê�¹æÎÏÓÞÜQá

ÑÐÆ+½�Ó�é5BDCE8$BDF ¼6½�èV»_¹·¼6½�Û4ÃÅÈ]ÈVÛ�ÎÞÃ;Î6½�ä;Ãż6¹]ÃÅÙ_È]½�ÛÎ6ÜUÃ;Îa×�½�Û6Ó�¼6¹·ÙÒ½�Î6Ü_½�Æ_¼�ÉÐÓ�½�Û�Û4Û�ÎÞÃ@ÎϽ�Î6É�¹]Ë_Ó�È]»_×_½ÃÅËE.1G�H GI� J(G�äÅÃ;È]»_½;á(éPÜ_¹·ÛaäÅÃ;È]»_½�¹·Û(ÎÏÜ�½P×_½�ÊSÃÅ»�È·Îaä;ÃÅÈ·»_½P»_Æ+ÉWËãÛ�ÎÏÃż�Î6»_ÆØÉW¼4»_Æ+ÉWËãÛ6Æ+½�Ó�¹·ÔUÓ�Ä�ÉÐ×_½Îϼ6ÃÅË_Û�¹·ÎϹ·ÉWË_Û�ð�Ê©ÉW¼�½ïÂ�ÃÅÄ�Æ_È]½;îRÃ;Ê�ÎϽ�¼�Î6½�Ä�ÆÒÉżÏÃż�ßyÛ6ÜV»�Î6×_Éåê�ËíÉÅÊÁÎÏÜ_½�Ó�ÉWÄ�Æ_»�Î6½�¼ÏñïáØéPÜ_¹]Û�Ê©½�Ã@ÎÏ»_¼�½¹]Û�»�Û6½�×ìÎÏÉ�½�Ë_Û6»_¼�½ØÓ�ÉWË_Û�¹]Û�ÎϽ�Ë�Ó�ßìÙ+½�Î�ê%½�½�ËKÎÏÜ_½ØÓ�ÉWÄÇÆ�»�ÎϽ�¼�ÄÇÉG×_½�È(ÉÅÊ�ÎÏÜ_½ØÆ_¼�ÉÐÓ�½�Û6Û�Û�ÎÞÃ;Î6½ÇÃ;Ë_×ÎÏÜ�½ã¼6½�Ã;È(Æ_¼�ÉÐÓ�½�Û6Û�Û�ÎÞÃ;Î6½ã»_ÆÒÉÅËyÛ�ÎÞÃ;¼�ÎÏ»�ÆKÉż�Ã;Ê�ÎϽ�¼�È]½�ÃåäG¹·Ë_º&Ó�ÉÅËVÎ6¼6ÉWÈ(ÄÇÉG×_½�ÛYê�Ü_½�¼�½�Æ�¼6ÉGÓ�½�Û�Û6¹·Ë_ºÉÅÊ)¹]Ë_Æ_»ÐÎÏÛ�ÜUÃÅÛàÙ+½�½�Ë�¹·ËVÎ6½�¼�¼6»_Æ�Î6½�×QáK:ÁßpÄÇÃ�LV¹]Ë�ºNMóË�LVË_Éåê�Ë£ÎÏÜ_½ ×_½ïÊSÃÅ»_È·Î�Û�ÎÞÃ;Î6½Íä;ÃÅÈ]»�½ÍÃ;Ë_×Ù:ß[ÓÞÜ_ÃÅË_ºW¹·Ë_ºàÎÏÉ�ÎÏÜ_½/»_Ë�LVË_Éåê�ËyäÅÃ;È]»_½Ý»_Æ+ÉWËçÓÞÜUÃÅË�ºW½�Û�Î6ÉàÓ�ÉÅËVÎ6¼6ÉWÈÄÇÉG×_½�ÛYê�Ü_½�¼6½w¹·Ë_Æ_»�Î6Û�Ãż�½Ë_ÉÅÎ&ÙÒ½�¹]Ë_ºsÆ_¼�ÉÐÓ�½�Û�Û�î)Î6Ü_½y»_Û6½yÉ;Ê/Ã;Ë »�Ë�LVË_Éåê�Ë�Û�ÎÞÃ;Î6½çäÅÃ;È]»_½[Ê©Éż6Ó�½�Û�¼6½�Û�ßGË_ÓÞÜ_¼�ÉWË_¹"O�Ã;ÎϹ·ÉWËòÉÅÊÎÏÜ�½�Ä�ÉG×_½�Èaê�¹æÎÏÜyÎÏÜ_½�ÉW»�Î6Û6¹·×_½ãê�ÉW¼�È]×KÃ;Ê�Î6½�¼ÝÃÅËK¹]Ë:ÎϽ�¼6¼6»�Æ�ÎϹ·ÉWËì¹]ËìÆ_¼6ÉGÓ�½�Û6Û�¹]Ë_º ¹]Ë_Æ�»�ÎÏÛ�áPC[Ã;ËVßÃÅÓ�Ó�¹]×�½�Ë:ÎÏÛ%ÜUÃ�äW½)Ù+½�½�ËàÓ�ÃÅ»_Û6½�×&Ù:ßãÎÏÜ_½YÃÅÛ�Û6»_Ä�Æ�ÎϹ·ÉWËØÎÏÜUÃ;ÎÁÎÏÜ�½YÆ_¼�ÉÐÓ�½�Û�Û�Û�ÎÏÃ;ÎϽó×_ÉG½�ÛÁË_ÉÅÎÁÓÞÜUÃÅË�ºW½

Õ 6

Page 23: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

Digital Altimeter 1

Values below -20 are treated as -20 and values above 2500 as 2500

Altitude

100 millisecondsnone

2.11 4.2

F

Input Value

F

T

T

= Obsolete

Startup

DA1-Alt-Signal

Receive DA1-Message FROM Digital-Altimeter-1

Time > Time (DA1-Message arrived) + 2 seconds

Source:

Type:

Possible Values (Expected Range):

Exception-Handling:

Units:

Granularity:

Arrival Rate (Load):

Min-Time-Between-Inputs:Max-Time-Between-Inputs:

Obsolescence:

Exception-Handling:

Description:

Comments:

References:

Appears in:

integer

-20..2500

2 seconds

feet AGL

1 foot

one per second average

DEFINITION

T

F

= FIELD (Altitude in DA1-Message)

= PREV (DA1-Alt-Signal)

Receive DA1-Message FROM Digital-altimeter-1

Receive DA1-Message FROM Digital-altimeter-1

Time > Time (DA1-Message arrived) + 2 seconds

¸(¹]ºW»�¼6½=%п�À(Â�ÃÅÄ�Æ_È]½�ÉÅÊ(ÃÅËE'�Ë_Æ_»ÐÎ�ÑÐÆ+½�Ó�¹·ÔUÓ�Ã;ÎϹ·ÉWËÕWÕ

Page 24: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

DOI-Power-On

4.102.12

Analog-ALT = Unknown

Dig-Alt1 = Unknown

Dig-Alt2 = Unknown

Dig1-Valid-and-Below

altitude will change to Unknown if all input signals are lost for 2 seconds.Because the altitude-status-signals change to obsolete after 2 seconds,

When at least one altimeter reports an altitude below the threshold, then the aircraft is

T T F

The altitude is assumed to be unknown at startup, when the pilot issuesa reset command, and when no recent input has come from any altimeter.

At least one altimeter reports a valid altitude above the threshold and none below.

At least one altimeter reports a valid altitude below the threshold..

No valid data is received from any altimeter (all report test or failed status).

m

m

m

m

m

2.12.1assumed to be below the threshold.

m

State Value

Altitude

Q�RTSURTVWRYX�ZTRY[T\]�^�^9RT_TV`[ba X9\

DEFINITION= Unknown

Startup T

T

T

T

T

Controls.Reset = T

T

= Below-threshold

Analog-Valid-and-Below

Dig2-Valid-and-Below T

T

= Cannot-be-determined

Analog-Alt = Invalid

Dig-Alt1 = Invalid

Dig-Alt2 = Invalid

T

T

T

c�d [Te�f RT[TZYRTX�ZYRT\2 secondsg hTZTRT^9iUaje9X9kUlm_TX9n�f ajX9o9\

p�RT[TZTV`aj^9iUaje9X9\

T

T

T

FTT T

F

F F

F F

Analog-Valid-and-Above

Dig1-Valid-and-Above

Dig2-Valid-and-Above

T

F

T

T F T

= At-or-above-threshold

q e�rr�RTX�iU[Y\

¸(¹]ºW»�¼6½sA�¿�À(Â�ÃÅÄ�Æ_È]½�ÉÅÊ(ÃÅËt'�Ë�Ê©½�¼�¼6½�×çÑGÎÏÃ;ÎϽvuÁÃż�¹TÃÅÙ�È]½�ÑÐÆ+½�Ó�¹·ÔUÓ�Ã;ÎϹ·ÉWË

Õ�w

Page 25: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

T

T

Altitude

2.5.1 4.3, 4.8.2

Macro

Description:

Comments:

References:

Appears in:

DEFINITION

THRES

Dig1-Valid-and-Below

Dig1-alt = Valid

DA1-Alt-Signal < 2000

¸¹]ºW»_¼�½sxпÁÀ(Â�ÃÅÄÇÆ�È]½�ÉÅÊ(ÃyC[ÃÅÓ�¼�É&ÑGÆÒ½�Ó�¹·Ô_Ó�Ã;Î6¹]ÉWË

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'XÊ%ÃàÄÇÉG×_½�ÈRÉ;ÊÁÃàÛ6»_Æ+½�¼�äG¹]Û6Éż�ßç×�¹]Û6Æ�ÈTÃ�ß ¹]Û)¹·Ë_Ó�È·»_×_½�×[¹]ËÍÎÏÜ_½wÛ�ÆÒ½�Ó�¹æÔUÓ�Ã;Î6¹]ÉW˪î+Î6Ü_½w»_Ë�LVË_Éåê�˹]ÛÝ»_Û�½�×íÊ©ÉW¼*Û�ÎÞÃ@ÎϽÇä;Ãż�¹TÃÅÙ�È]½�Û�¹·Ë,ÎÏÜ�½àÛ6»�ÆÒ½�¼�äG¹]Û�ÉW¼�ß,×_¹]Û�Æ_ÈTÃ�ßKÄ�ÉÐ×_½�È�ÉWË_È·ßì¹æÊ�ÎÏÜ�½àÛ�ÎÏÃ;ÎϽÇÉÅÊPÎÏÜ�½×_¹·Û6Æ_È]Ãåß,Ó�Ã;ËpÓÞÜUÃ;Ë_ºW½�¹]Ë_×�½�Æ+½�Ë_×_½�Ë:ÎÏÈ·ßIÉÅÊóÎÏÜ_½�Û�ÉÅÊ�Î�ê�Ã;¼6½ÅázÌ)Î6Ü_½�¼�ê�¹]Û6½;î%Û�»_ÓÞÜëäÅÃ;¼6¹TÃ;Ù_È]½�ÛwÄw»_Û�ÎÛ6Æ+½�Ó�¹·Ê�ßwÃÅËã¹]Ë_¹æÎϹ]ÃÅÈ:äÅÃ;È]»_½�ð©½Å᧺_áæî:Ù_ÈTÃÅË�L+î�O�½�¼�É_î:½�Î6ÓÅáµñ*ÎÏÜUÃ@Î4Û6Ü_ÉÅ»_È]×ãÙ+½PÛ6½�ËVÎ�ê�Ü_½�ËãÎÏÜ_½PÓ�ÉWÄÇÆ�»�ÎϽ�¼¹]ÛP¼�½�Û�ÎÞÃż�ÎϽ�תá

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Page 27: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

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Page 28: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

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Page 29: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

= ...

= ...

(number of outputs N within an interval of time D)

(rate at which actuators can accept and react to data produced by component)

Destination:

Acceptable Values:

Units:

Granularity:

Exception Handling:

Hazardous Values:

Timing Behavior:

Initiation Delay:

Completion Deadline:

Reversed By:

Comments:

References:

DEFINITION

Name

Load:

Min time between outputs:

Max time between outputs:

Exception-Handling:

Output Capacity Assumptions:

Hazardous timing behavior:

Feedback Information:

Variables:

Values:

Relationship:

Min. time (latency):

Max. time:

Exception Handling:

Output Command

Õ�Ý

Page 30: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

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Name

p�RT[TZTV`aj^9iUaje9X9\q e�rr�RTX�iU[Y\Q�RTSURTVWRYX�ZTRY[T\]�^�^9RT_TV`[ba X9\

DEFINITION

= ...

= ...

Operating Mode

¸(¹·ºW»_¼6½ Þ�¿¬ß�½�Ë_½�¼6ÃÅÈO¸UÉW¼6Ä ÉÅÊ(ÃÇÌ�Æ+½�¼6Ã;ÎϹ·Ë_º�CÍÉÐ×�½�ÛYÑÐÆ+½�Ó�¹æÔUÓ�Ã@ÎϹ]ÉÅËÕ Þ

Page 31: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

startup, timeouts, transitions to particularmodes or states such as maintenance or

This table must include all conditions under

off-line mode, ...

which the value changes to unknown, such asStartup T

...

DEFINITION

= Unknown

= ...

c�d [Te�f RT[TZYRTX�ZYRT\g hTZTRT^9iUaje9X9kUlm_TX9n�f ajX9o9\

State Value

Name

p�RT[TZTV`aj^9iUaje9X9\q e�rr�RTX�iU[Y\Q�RTSURTVWRYX�ZTRY[T\]�^�^9RT_TV`[ba X9\

Q�RTfj_YiURTna X�^9à9iá[Y\

Q�RTfj_YiURTnâ X�^9à9iá[Y\(so can check that behavior specified for all values of related inputs, assumes stays insame state for other inputs)

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wWÖ

Page 32: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

(the applicability of these will depend on the value type)

(number of inputs N within an interval of time D)

(continuous, periodic, random, s-r)

(if s-r)

Startup

= FIELD ( ... )

Receive xx-Message from ...

Receive xx-message from ... F

(timing statement)

T

Receive xx-message from ...

(timing statement)

F

T

Event that triggers change

Conditions under whichprevious value used.

NameInput Value

Source:

Type:

Possible Values (Expected Range):

Units:Granularity:Exception-Handling:

Timing Behavior:

Load:Min-Time-Between-Inputs:Max-Time-Between-Inputs:Max-Time-Before-First-Input:Related Outputs:

Latency : Min-time-after-outputLatency : Min-time-after-outputLatency : Min-time-after-output Min-time-after-output

Exception-Handling:

= Obsolete

T

= PREV ( .. )

DEFINITION

Exception-Handling:

Description:

Comments:

References:

Appears in:

Obsolescence:

¸(¹·ºW»_¼6½�6�6W¿¬ß�½�Ë_½�¼6ÃÅÈO¸UÉW¼6Ä ÉÅÊ(ÃÅËE'�Ë_Æ_»�Î)ÑÐÆ+½�Ó�¹·ÔUÓ�Ã;ÎϹ·ÉWË

w 6

Page 33: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

= FIELD ( ... )

(number of inputs N within an interval of time D)

I’M NOT SURE ABOUT THE FORM OF THIS YET

= Obsolete

DEFINITION

= PREV ( .. )

Obsolescence:

Exception-Handling:

Description:

Comments:

References:

Appears in:

Source:

Type:

Possible Values (Expected Range):

Name

Units:

Granularity:

Exception-Handling:

Timing Behavior:

Load:

Min-Time-Between-Inputs:

Max-Time-Between-Inputs:

Control Input

Exception-Handling:

¸(¹·ºW»_¼6½76 Õ ¿¬ß�½�Ë_½�¼ÏÃÅÈO¸UÉW¼�ÄÚÉÅÊ(ù��ÉÅËVÎ6¼6ÉWÈã'�Ë�Æ_»�Î)ÑÐÆ+½�Ó�¹æÔUÓ�Ã@ÎϹ]ÉÅËw:Õ

Page 34: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

= ...

(usually blank or message)

(number of outputs N within an interval of time D)

= ...

I’M NOT SURE ABOUT THE FORM OF THIS YET

(rate at which humans can accept and react to data produced by component)

Comments:

References:

Reversed By:

NameDisplay Output

Type:

Acceptable Values:

Hazardous Values:Granularity:Units:

Update Requirements:

Update Delay:

Destination:

DEFINITION

Update Completion Deadline:Output Capacity Assumptions:

Update Load:Min update rate:Max update rate:

Deletion Requirements (including data age):Hazardous timing behavior:Exception-Handling:

Failure Indication:

(discrete values, queue)

¸(¹]ºW»�¼6½�6 w ¿¬ß�½�Ë�½�¼ÏÃ;ÈO¸8Éż6ÄÚÉ;ÊaÃ�2�¹]Û�Æ_ÈTÃ�ß�Ì�»ÐÎÏÆ_»�ÎYÑGÆÒ½�Ó�¹·Ô_Ó�Ã;Î6¹]ÉWË

w~w

Page 35: Representation - Massachusetts Institute of Technologysunnyday.mit.edu/papers/user2.pdf · Blackbox Behavior Physical Representation Principles System Design Purpose System Design

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p�RT[TZTV`aj^9iUaje9X9\q e�rr�RTX�iU[Y\Q�RTSURTVWRYX�ZTRY[T\]�^�^9RT_TV`[ba X9\

Name

DEFINITION

Macro

¸(¹]ºÅ»_¼6½�6�¾�¿¬ß�½�Ë_½�¼6ÃÅÈM¸UÉW¼6Ä ÉÅÊ4ÃyC[Ã;Ó�¼6ÉàÑÐÆ+½�Ó�¹·ÔUÓ�Ã;ÎϹ·ÉWËw ¾