introduction to operations management - yustom - yust...

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Introduction to Operations Management

Process Selection and Process Selection and Facility Layout (Ch.6)Facility Layout (Ch.6)

Hansoo Kim ( 金翰秀 )Dept. of Management Information

Systems, YUST

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What you should do! Review Capacity Planning Read Chapter 6 and 6s

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OM Overview

Class Overview(Ch. 0)

Project Management

(Ch. 17)

Strategic Capacity Planning(Ch. 5, 5S)

Operations, Productivity, and Strategy

(Ch. 1, 2)

Mgmt of Quality/Six Sigma Quality

(Ch. 9, 10)

Supply Chain Management

(Ch 11)

Location Planning and Analysis

(Ch. 8)

Demand MgmtForecasting

(Ch 3)

Inventory Management

(Ch. 12)

Aggregated Planning

(Ch. 13)

Queueing/ Simulation

(Ch. 18)

MRP & ERP (Ch 14)

JIT & Lean Mfg System

(Ch. 15)

Term Project

Process Selection/

Facility Layout; LP(Ch. 6, 6S)X X X X

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Key Terms영어 중국어 영어 중국어

Assembly line 组装线 Line balancing 生产线平衡Automation 自动化 Numerically controlled(N/C)

machines数控机床

Balance delay 生产线闲置率 Precedence diagram 先后顺序图Cellular production 单元制造 Process layout 工艺原则布置Computer-aided manufacturing

计算机辅助制造 Production line 生产线Computer-integrated manufacturing

计算机集成制造 Product layout 产品原则布置Cycle time 节拍 Product or service

profiling产品或服务工艺

Fixed-position layout 定位布置 Project 项目Flexible manufacturing system

柔性制造系统 Robot 机器人Group technology 成组技术 Technological innovation 技术创新Intermittent processing

间歇加工 technology 技术

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Learning Objectives Explain the strategic importance of process selection. Explain the influence that process selection has on an

organization. Describe the basic processing types. Discuss automated approaches to processing. Explain the need for management of technology. List some reasons for redesign of layouts. Describe the basic layout types. List the main advantages and disadvantages of

product layouts and process layouts. Solve simple line-balancing problems. Develop simple process layouts.

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Capacity and Process Selection

Process Strategy (Key Aspects)1. Capital Intensity2. Process Flexibility

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Process Selection Strategy ( 생산전략 , 공정설계 전략 ) Process Selection ( 공정선택 )

Deciding on the way production of goods or services will be organized

“ 제품과 서비스를 어떤 방식어떤 방식으로 생성해 낼 것인가 ?” 에 대한 방안 Process = Transformation

원자재에서 제품 ( 혹 서비스 ) 로 변화되는 과정

Objective( 목적 ) Meet or exceed customer requirements ( 요구사항 ) Meet cost & managerial goals 최소의 비용으로 고객의 요구사항을 극대화 한다 !

Long-term effect ( 장기적인 영향력이 있다 ) Product & Volume Flexibility Costs & Quality

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생각해 볼 문제들… 어떤 종류의 생산 (or 서비스 ) 방식이 있을까 ?

(Which types of process strategy can exist?)

생산 (or 서비스 ) 방식을 결정하는데 고려해야 하는 요소들은 어떤 것이 있을까 ?

Which factors should be considered to select the process strategy?

예제 홍콩반점 건강검진센타 빙천맥주공장 자동차 조립공장

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4 가지 공정설계 전략 (Four Process Strategies)

Process Focus ( 공정중심 ) Product Focus ( 제품중심 ) Repetitive Focus ( 공통모듈중심 ) (Assembl

y Line) Mass Customization Focus

( 대량맞춤생산 )

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Machining Process Process Time ( 공정시간 )

= Setup Time ( 준비시간 ) + Machining Time (가공시간 )

How is the utilization of the Machine?

Machine

S-A-A-A-A-S-B-B-B-B

S-A-S-B-S-A-S-B-S-A-S-B-S-A-S-B

S = Setup Time

장단점장단점 ??

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Process-Focused Strategy ( 공정중심전략 ) Facilities( 설비 ) are organized by processprocess Similar processes are together

Example: All drill presses are together Low volume, high variety products

( 다품종 소량 ) ‘JumbledJumbled’ flowflow ( 뒤범벅 흐름 ) Other names

Intermittent process Job shop*Job shop*

OperationProduct A

Product B

11 22 33

12

Process-Focused Strategy Examples

Bank

© 1995 Corel Corp.

Machine Shop© 1995 Corel Corp.

Hospital© 1995 Corel Corp.

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Process Focus (job shop)설비 배치

L

L

L

L

L

L

L

L

L

L M

M

M

M

D

D

D

D

D

D

D

D

G

G

G

G

G

G

A A AReceiving andShipping Assembly

Painting Department

Lathe DepartmentMilling

Department Drilling Department

Grinding Department

P

P

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Process Focused Strategy장단점 장점

Greater product flexibility ( 다양한 제품을 생산 )

More general purposegeneral purpose equipmentequipment( 범용성이 높은 설비 사용 )

Lower initial capital investment( 낮은 초기 설비 투자 )

단점 High variable costs ( 높은 변동비 ) More highly trained personnel ( 다기능공 ) More difficult production planning & control

( 생산계획 및 통제의 어려움 ) Low equipment utilization (5% to 25%)

( 낮은 설비 효율성 )

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Product Focused Strategy( 제품중심전략 ) Facilities( 설비 ) are organized by productproduct High volume, low variety products

( 소품종 다량생산 ) Where found

Discrete unit manufacturing Continuous process manufacturing

Other names Flow Line productionFlow Line production Continuous production

Products A & B1 2 3

Operation

2 4 3

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Product Focused Examples

© 1995 Corel Corp.

Light Bulbs (Discrete)

Paper (Continuous)© 1984-1994 T/Maker Co.

© 1995 Corel Corp.

Soft Drinks (Continuous, then Discrete)

Mass Flu Shots (Discrete)

© 1995 Corel Corp.

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Product Focus 설비 배치L

A L

M D

M D

L G

L

InIn

OutOut

M

A L

S D

G D

G P

L

InIn

OutOut

Product AProduct A

Product BProduct B

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Product Focused Strategy장단점 장점

Lower variable cost per unit ( 낮은 변동비 )

Lower but more specialized labor skills Easier production planning and control

( 생산계획 및 통제의 용이성 ) Higher equipment utilization (70% to 90%)

( 설비의 높은 가동율 ) 단점

Lower product flexibility ( 제품 종류가 한정 ) More specialized equipment ( 전용설비 ) Usually higher capital investment

( 높은 초기투자비용 )

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Repetitive Focused Strategy( 공통모쥴중심 전략 ) Facilities often organized by assembly lines

( 일반적으로 조립라인으로 설비가 구성 ) Characterized by modulesmodules

Parts & assemblies made previously Modules combined for many output

optionsoptions Other names

Assembly line Production line

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Repetitive FocusModulesModulesParts or components of Parts or components of a product previously a product previously preparedprepared

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Repetitive Focused Strategy -Considerations ( 고려사항들… ) More structured than process-focused, less

structured than product focused제품 자체가 좀 더 구조적으로 잘 구성되어있다 Enables quasi-customizationquasi-customization다양한 다양한 고객의 요구사항을 좀 더 잘 반영한다 Using modules, it enjoys economic

advantage of continuous process, and custom advantage of low-volume, high-variety model

중심이 되는 공통 모듈을 다양한 요구의 옵션 ( 선택 사향 ) 과 결합한 생산 방식

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Repetitive-Focused Strategy Examples

Truck

© 1995 Corel Corp.

Clothes Dryer

© 1995 Corel Corp.

Fast Food

McDonald’sover 95 billion served

© 1984-1994 T/Maker Co.

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Mass-Customization Focused Strategy ( 대량맞춤생산전략 ) Rapid, low-cost production that

caters to constantly changing unique customer desires

주문생산의 장점 : Customization ( 고객의 Needs 에 적극적으로 대응 )

대량생산의 장점 : Low-cost rapid Production ( 저비용 효율생산 )

여러 전략의 장점을 정보시스템과 OM 기법을 통해 결합한 전략 방식

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Process Strategies

Rapid throughput techniques

Mass Customization

Modular techniques

Repetitive FocusModular design

Flexible equipment

Product-focusedLow variety, high volume

High utilization (70% - 80%)Specialized equipment

Process-focusedHigh variety, low volume

Low utilization (5% - 20%)General purpose equipment

Effective scheduling techniques

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A Comparison (1)Process Focus

(Job Shop)(Low volume, High variety)

Repetitive Focus

(Modular)

Product focus(High-volume, low-variety)

Mass Customization(High-volume, high-variety)

1. Small quantity, large variety of products

Long runs, standardized product, from modules

Large quantity, small variety of products

Large quantity, large variety of products

2. General purpose equipment ( 이것도 저것도 생산해야 하기때문에… )

Special equipment aids in use of assembly line

Special purpose equipment

Rapid changeover on flexible equipment

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A Comparison (2)Process Focus Repetitive

FocusProduct

focusMass

Customization

3 Broadly skilled operators (두루두루 잘 알아야 한다 )

Modestly trained employees

Operators less broadly skilled

Flexible operators trained for customization

4 Many instructions because of change in jobs

Reduced training and number of job instructions

Few work orders and job instructions

Custom orders require many instructions

5 Raw material high relative to product value

JIT techniques used

Raw material low relative to product value

Raw material low relative to product value

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A Comparison (3)Process Focus Repetitive

FocusProduct focus Mass

Customization

6 WIP high relative to output

JIT techniques used

WIP low relative to output

WIP driven down by JIT, kanban, lean production

7 Units move slowly thru plant

Movement measured in hours & days

Units move swiftly thru facility

Goods move swiftly thru facility

8 Finished goods made to order, not stored

Finished goods made to frequent forecasts

Finished goods made to forecast, then stored

Finished goods made to order

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A Comparison (4)Process Focus Repetitive

FocusProduct focus Mass

Customization9 Scheduling complex and concerned with trade-off between inventory, capacity, and customer service

Scheduling based on building models from a variety of forecasts

Scheduling relatively simple, concerns establishing sufficient rate of output to meet forecasts

Scheduling sophisticated to accommodate customization

10 Fixed costs low, variable costs high

Fixed costs dependent on flexibility of facilities

Fixed costs high, variable costs low

Fixed costs high; variable costs must be low

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A Comparison (5)Process Focus Repetitive

FocusProduct focus Mass

Customization11 Costing, done by job, is estimated prior to doing job but only known after doing job

Costs usually known based on experience

Because of high fixed costs, cost dependent on utilization of capacity

High fixed costs and dynamic variable costs

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Volume and Variety of ProductsVolume andVariety ofProducts

Low Volume HighVariety Process

(Intermittent)

RepetitiveProcess

(Modular)

High VolumeLow Variety

Process(Continuous)

One or very fewunits per lot

Projects

Very small runs, highvariety

Job Shops

Modest runs, modestvariety

DisconnectedRepetitive

Long runs, modestvariations

ConnectedRepetitive

Very long runs,changes inattributes

Continuous

Equipment utilization 5%-25% 20%-75% 70%-80%

Poor Strategy(High variable

costs)

Mass Customization

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Areas of Technology Machine technology Automatic identification systems (AIS)

Bar-code, RFID Process control Vision system Robot Automated storage and retrieval systems

(ASRS) Flexible manufacturing systems (FMS) Computer-integrated manufacturing (CIM)

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FMS 에 의한 생산라인의 개념도

1

23

45

6

7

8

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FMS 예

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자동창고

중앙관제실

공구저장소

공구무인반송차

머시닝센터

작업물 무인운반차

준비작업장

차팔렛트 반송컨베이어라인

FMS 예

세정실

35

FMS 예

36

37

Types of Robot Cylindrical

Polar

Cartesian

Joint Arm

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FMS Machine

39

ASRS ( 자동창고 )

40

AGV ( 무인운반차 )

41

AGVS ( 무인운반차 시스템 )

http://www.steinbockus.com/AGVs/animation.gif

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Computer Integrated Manufacturing(CIM)

43

Facility Layout Design

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Objectives of Facility Layout Develop an economical layout which will meet

the requirements of: product design and volume (product strategy) process equipment and capacity (process strategy) quality of work life (human resource strategy) building and site constraints (location strategy)

사내물류비용의 최소화 공간의 효율적 활용 노동력의 효율적 활용

불필요한 움직임을 최소화함 병목현상을 완화 제조 및 서비스 시간 단축

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What is Facility Layout Location or arrangement of everything

within & around buildings Objectives are to maximize

Customer satisfaction Utilization of space, equipment, & people Efficient flow of information, material, &

people Employee morale & safety

46

Types of Layouts Fixed-position layout Process-oriented layout Office layout Retail layout Warehouse layout Product-oriented layout

47

Emergency Room Layout(Process-Oriented Layout)

Surgery

RadiologyE.R. beds Pharmacy Billing/exit

E.R.Triage room

E.R. AdmissionsPatient B - erratic pacemaker

Patient A - broken leg

Hallway

48

Steps in Developing aProcess-Oriented Layout1 Construct a “from-to matrix”2 Determine space requirements for each

department3 Develop an initial schematic diagram4 Determine the cost of this layout5 By trial-and-error (or more sophisticated

means), try to improve the initial layout6 Prepare a detailed plan that evaluates

factors in addition to transportation cost

49

Cost of Process-Oriented Layout

j department and i department

between load a move cost to Cj department toi department

from moved loads ofnumber Xsdepartment individual ji,

sdepartmentor centers work ofnumber totaln where

CX cost Minimize

ij

ij

n

1i

n

1jijij

50

Interdepartmental Flow of Parts1 2 3 4 5 6

1

2

3

4

5

6

50 100 0 0 20

30 50 10 0

20 0 100

50 0

0

51

Possible Layout 1

AssemblyDepartment

(1)

PrintingDepartment

(2)

Machine ShopDepartment

(3)

ReceivingDepartment

(4)

ShippingDepartment

(5)

TestingDepartment

(6)

Room 1 Room 2 Room 2

Room 4 Room 5 Room 660’

40’

52

Interdepartmental Flow Network Showing Number of Weekly Loads

100

50 30

1020

50

20

10050

2 3

4 5 6

11

근접운반비 (Adjacent Cost) = $1, 비근접운반비 (Non-Adjacent C.) = $2

Total Cost = 50+200+40+30+50+10+40+100+50 = $570

53

Possible Layout 2

PaintingDepartment

(2)

AssemblyDepartment

(1)

Machine ShopDepartment

(3)

ReceivingDepartment

(4)

ShippingDepartment

(5)

TestingDepartment

(6)

Room 1 Room 2 Room 2

Room 4 Room 5 Room 660’

40’

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Interdepartmental Flow Graph Showing Number of Weekly Loads

2 1 3

654

10050

30

10

20

50

20 10050

근접운반비 (Adjacent Cost)= $1, 비근접운반비 (Non-Adjacent C.)=$2

Total Cost = 50+100+20+60+50+10+40+100+50=$480

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Computer Programs to Assist in Layout CRAFT SPACECRAFT CRAFT 3-D MULTIPLE CORELAP ALDEP COFAD FADES - expert system

56

Cellular Layout - Work Cells A temporary product-orient

arrangement of machines and personnel in what is ordinarily a process-oriented facilities

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Work Cell Floor PlanOfficeOffice

Tool RoomTool RoomWork CellWork Cell

SawsSaws DrillsDrills

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Improving Layouts by Moving to the Work Cell Concept

59

Work Cell Advantages

InventoryFloor space

Direct labor costs

Equipment utilizationEmployee

participationQuality

60

Office Layout Design positions people,

equipment, & offices for maximum information flow

Arranged by process or product Example: Payroll dept. is by process

Relationship chart used Examples

Insurance company Software company

61

Relationship Chart ( 부문상호관계표 )

1 PresidentO

2 Costing UA A

3 Engineering IO

4 President’s Secretary

1122

33

Ordinary closeness: President (1) & Costing (2)

Absolutely necessary: President (1) & Secretary (4)

44

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Office Relationship Chart1 President

2 Chief Technology Officer

3 Engineer’s Area

4 Secretary

5 Office entrance

7 Equipment cabinet

8 Photocopy equipment

9 Storage room

9 Storage room

UIIAUOE

IOEI

OAOAXOUE

A I IEUA

II EAX

UUO

OU

O

Val.

Closeness

A Absolutely necessary

E Especially important

I Important

O Ordinary OK

U Unimportant

X Not desirable

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Retail /Service Layout -Grid Design

OfficeOffice CartsCarts Check-Check-outout

Grocery StoreGrocery StoreMeatBread

Milk

ProduceFrozen Foods

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Store Layout - with Dairy, Bread, High Drawer Items in Corners

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Warehouse Layout Design balances space (cube)

utilization & handling cost Similar to process layout

Items moved between dock & various storage areas

Optimum layout depends on Variety of items

stored Number of items picked

66

An Assembly Line Layout

67

Line Balancing

Precedence diagramPrecedence diagram Network showing order Network showing order

of tasks and restrictions of tasks and restrictions on their performanceon their performance

Cycle timeCycle time Maximum time product Maximum time product

spends at any one spends at any one workstationworkstation

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Line Balancing

Precedence diagramPrecedence diagram Network showing order Network showing order

of tasks and restrictions of tasks and restrictions on their performanceon their performance

Cycle timeCycle time Maximum time product Maximum time product

spends at any one spends at any one workstationworkstation

Cd = production time availabledesired units of output

Cycle time example

Cd = (8 hours x 60 minutes / hour)(120 units)

Cd = = 4 minutes480120

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Flow Time vs Cycle Time Cycle time = max time spent at any Cycle time = max time spent at any

station station Flow time = time to complete all Flow time = time to complete all

stationsstations

70

Flow Time vs Cycle Time Cycle time = max time spent at any Cycle time = max time spent at any

station station Flow time = time to complete all Flow time = time to complete all

stationsstations

1 2 3

4 minutes4 minutes 4 minutes4 minutes 4 minutes4 minutes

Flow time = 4 + 4 + 4 = 12 minutesFlow time = 4 + 4 + 4 = 12 minutesCycle time = max (4, 4, 4) = 4 minutesCycle time = max (4, 4, 4) = 4 minutes

71

Efficiency of Line

ii

ii = 1= 1

ttii

nCnCaaEE = =

ii

ii = 1= 1

ttii

CCddNN = =

EfficiencyEfficiency Minimum number Minimum number of workstationsof workstations

wherewhere

ttii = completion time for element = completion time for element iijj = number of work elements= number of work elementsnn = actual number of workstations= actual number of workstationsCCaa = actual cycle time= actual cycle timeCCdd = desired cycle time= desired cycle time

72

Line Balancing Process

1. Draw and label a precedence diagram.1. Draw and label a precedence diagram.2. Calculate the desired cycle time required for the 2. Calculate the desired cycle time required for the

line.line.3. Calculate the theoretical 3. Calculate the theoretical

minimum number of workstations.minimum number of workstations.4. Group elements into workstations, 4. Group elements into workstations,

recognizing cycle time and recognizing cycle time and precedence constraints.precedence constraints.

5. Calculate the efficiency of the line.5. Calculate the efficiency of the line.6. Stop if theoretical minimum number of 6. Stop if theoretical minimum number of

workstations on an acceptable efficiency level workstations on an acceptable efficiency level reached. If not, go back to step 4.reached. If not, go back to step 4.

73

Line Balancing

WORK ELEMENTWORK ELEMENT PRECEDENCEPRECEDENCE TIME (MIN)TIME (MIN)

AA Press out sheet of fruitPress out sheet of fruit —— 0.10.1BB Cut into stripsCut into strips AA 0.20.2CC Outline fun shapesOutline fun shapes AA 0.40.4DD Roll up and packageRoll up and package B, CB, C 0.30.3

Desired unit of output : 6,000 unitsAvailable working hour a day : 40 Hrs

74

Line Balancing

WORK ELEMENTWORK ELEMENT PRECEDENCEPRECEDENCE TIME (MIN)TIME (MIN)

AA Press out sheet of fruitPress out sheet of fruit —— 0.10.1BB Cut into stripsCut into strips AA 0.20.2CC Outline fun shapesOutline fun shapes AA 0.40.4DD Roll up and packageRoll up and package B, CB, C 0.30.3

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

75

Line Balancing

WORK ELEMENTWORK ELEMENT PRECEDENCEPRECEDENCE TIME (MIN)TIME (MIN)

AA Press out sheet of fruitPress out sheet of fruit —— 0.10.1BB Cut into stripsCut into strips AA 0.20.2CC Outline fun shapesOutline fun shapes AA 0.40.4DD Roll up and packageRoll up and package B, CB, C 0.30.3

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

Cd = = = 0.4 minute40 hours x 60 minutes / hour6,000 units

24006000

N = = = 2.5 workstations1.00.4

0.1 + 0.2 + 0.3 + 0.40.4

76

Line Balancing

WORK ELEMENTWORK ELEMENT PRECEDENCEPRECEDENCE TIME (MIN)TIME (MIN)

AA Press out sheet of fruitPress out sheet of fruit —— 0.10.1BB Cut into stripsCut into strips AA 0.20.2CC Outline fun shapesOutline fun shapes AA 0.40.4DD Roll up and packageRoll up and package B, CB, C 0.30.3

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

Cd = = = 0.4 minute40 hours x 60 minutes / hour6,000 units

24006000

N = = = 2.5 workstations1.00.4

0.1 + 0.2 + 0.3 + 0.40.4 3

workstations

77

Line Balancing

WORK ELEMENTWORK ELEMENT PRECEDENCEPRECEDENCE TIME (MIN)TIME (MIN)

AA Press out sheet of fruitPress out sheet of fruit —— 0.10.1BB Cut into stripsCut into strips AA 0.20.2CC Outline fun shapesOutline fun shapes AA 0.40.4DD Roll up and packageRoll up and package B, CB, C 0.30.3

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

78

Line Balancing

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

REMAINING REMAININGWORKSTATION ELEMENT TIME ELEMENTS

79

Line Balancing

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

REMAINING REMAININGWORKSTATION ELEMENT TIME ELEMENTS

1 A 0.3 B, C

80

Line Balancing

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

REMAINING REMAININGWORKSTATION ELEMENT TIME ELEMENTS

1 A 0.3 B, CB 0.1 C, D

81

Line Balancing

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

REMAINING REMAININGWORKSTATION ELEMENT TIME ELEMENTS

1 A 0.3 B, CB 0.1 C, D

2 C 0.0 D

82

Line Balancing

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

REMAINING REMAININGWORKSTATION ELEMENT TIME ELEMENTS

1 A 0.3 B, CB 0.1 C, D

2 C 0.0 D3 D 0.1 none

83

Line Balancing

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

REMAINING REMAININGWORKSTATION ELEMENT TIME ELEMENTS

1 A 0.3 B, CB 0.1 C, D

2 C 0.0 D3 D 0.1 none

A, B C D

Work station 1

Work station 2

Work station 3

0.3 minute

0.4 minute

0.3 minute

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Line Balancing

0.10.1

0.20.2

0.40.4

0.30.3D

B

C

A

CCdd = 0.4 = 0.4NN = 2.5 = 2.5

REMAINING REMAININGWORKSTATION ELEMENT TIME ELEMENTS

1 A 0.3 B, CB 0.1 C, D

2 C 0.0 D3 D 0.1 none

A, B C D

Work station 1

Work station 2

Work station 3

0.3 minute

0.4 minute

0.3 minute

E = = = 0.833 = 83.3%0.1 + 0.2 + 0.3 + 0.43(0.4)

1.01.2

85

Announcement Next week Exam I

Concepts, Terms Calculation Problems

Examples, Solved problems, and HW HW ( 제출하지 않음 )

Example 1, 2 Solved Problem 1

86

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