Ch4(Process Analysis)

8/18/2019 Ch4(Process Analysis)

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©The McGraw-Hill Companies,


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Chapter 4Process Analysis


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• Process Analysis

• Process Flowcharting

• Types of Processes

• Process Performance Metrics

OBJECTIVES


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Process Analysis Terms

• Process Is any part of an organi!ation that

ta"es inp#ts an$ transforms them into o#tp#ts

• Cycle Time Is the a%erage s#ccessi%e time

&etween completions of s#ccessi%e #nits

• 'tili!ation Is the ratio of the time that a

reso#rce is act#ally acti%ate$ relati%e to the

time that it is a%aila&le for #se


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Process Flowcharting

Defined

• Process flowcharting is the #se of a $iagram to

present the ma(or elements of a process

• The &asic elements can incl#$e tas"s or

operations) flows of materials or c#stomers)

$ecision points) an$ storage areas or *#e#es

• It is an i$eal metho$ology &y which to &egin

analy!ing a process


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Flowchart

Sym&ols

Tasks or operations Examples: Giving an

admission ticket to a

customer, installing a

engine in a car, etc.

Examples: Giving an

admission ticket to a

customer, installing a

engine in a car, etc.

Decision Points Examples: How much

change should be

given to a customer,

which wrench shouldbe used, etc.

Examples: How much

change should be

given to a customer,

which wrench shouldbe used, etc.

Purpose and Examples


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Examples: heds,

lines o! people waiting

!or a service, etc.

Examples: heds,

lines o! people waiting

!or a service, etc.

Examples: "ustomers

moving to a seat,

mechanic getting a

tool, etc.

Examples: "ustomers

moving to a seat,

mechanic getting a

tool, etc.

torage areas or

#ueues

$lows o!

materials or

customers

Flowchart

Sym&ols Purpose and Examples


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E+ample Flowchart of St#$ent ,oing to

School %es

&o

Goo!

o!!

Go to

school

toda'(

)alk to

class

Drive to

school


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Types of Processes

Single-stage Process

tage *

tage * tage + tage

Multi-stage Process


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Types of Processes -Contin#e$.

tage * tage +-u!!er

Multi-stage Process with Buffer

A ffer refers to a storage area &etween stages

where the o#tp#t of a stage is place$ prior to

&eing #se$ in a $ownstream stage


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Other Process Terminology• Bloc"ing

– Occ#rs when the acti%ities in a stage m#st stop &eca#sethere is no place to $eposit the item (#st complete$

– If there is no room for an employee to place a #nit of wor"

$own) the employee will hol$ on to it not a&le to contin#e

wor"ing on the ne+t #nit• Star%ing

– Occ#rs when the acti%ities in a stage m#st stop &eca#se

there is no wor"

– If an employee is waiting at a wor" station an$ no wor" iscoming to the employee to process) the employee will

remain i$le #ntil the ne+t #nit of wor" comes


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Other Process Terminology -Contin#e$.

• Bottlenec" – Occ#rs when the limite$ capacity of a process

ca#ses wor" to pile #p or &ecome #ne%enly

$istrite$ in the flow of a process

– If an employee wor"s too slow in a m#lti/stageprocess) wor" will &egin to pile #p in front of that

employee0 In this is case the employee represents

the limite$ capacity ca#sing the &ottlenec"0

• Pacing – 1efers to the fi+e$ timing of the mo%ement of items

thro#gh the process


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Other Types of Processes

• Ma"e/to/or$er

– Only acti%ate$ in response to an act#al or$er

– Both wor"/in/process an$ finishe$ goo$s in%entory"ept to a minim#m

• Ma"e/to/stoc"

– Process acti%ate$ to meet e+pecte$ or forecast

$eman$

– C#stomer or$ers are ser%e$ from target stoc"ing

le%el


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Process Performance Metrics

• Operation time 2 Set#p time 3 1#n time

• Thro#ghp#t time 2 A%erage time for a #nit to

mo%e thro#gh the system

• Velocity 2 Thro#ghp#t time Val#e/a$$e$ time

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Process Performance Metrics -Contin#e$.

• Cycle time 2 A%erage time &etweencompletion of #nits

• Thro#ghp#t rate 2 4 0

Cycle time

• Efficiency 2 Act#al o#tp#t

Stan$ar$ O#tp#t

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Process Performance Metrics -Contin#e$.

• Pro$#cti%ity 2 O#tp#t

Inp#t

• 'tili!ation 2 Time Acti%ate$

Time A%aila&le

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Cycle Time E+ample

S#ppose yo# ha$ to pro$#ce 566 #nits in 76 ho#rs to

meet the $eman$ re*#irements of a pro$#ct0 8hat is

the cycle time to meet this $eman$ re*#irement9

S#ppose yo# ha$ to pro$#ce 566 #nits in 76 ho#rs to

meet the $eman$ re*#irements of a pro$#ct0 8hat is

the cycle time to meet this $eman$ re*#irement9

Answer: There are 4,!! minutes "#!minutes$hour x ! hours% in ! hours& So the

a'erage time (etween completions would ha'eto (e: )*cle time + 4,!!$#!! units + minutes&

Answer: There are 4,!! minutes "#!minutes$hour x ! hours% in ! hours& So the

a'erage time (etween completions would ha'eto (e: )*cle time + 4,!!$#!! units + minutes&

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Process Thro#ghp#t Time 1e$#ction

• Perform acti%ities in parallel

• Change the se*#ence of acti%ities

• 1e$#ce interr#ptions

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Ch4(Process Analysis)

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