제 14 주차 강의
 14 주차
 교과서 18장: Training and other Management Practice(Learning Effect 포함)
 Learning Effect, Motivation, Lean Manufacturing, Toyota Production System,
 1-12주차
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산업공학, 산업 발전 역사, IE 인재의 모습
교과서 1-2장: Methods, Problem Solving Tools
제조 프로세스
교과서 3~6장: Operation, Manual, Equip., Tool, Workplace 개선
교과서 7~8장: Cognitive work, Safety(개괄적으로)
교과서 9~10장: Implementation, Job Evaluation
Time Study(rating, allowance),
Standard Data(Machining, Welding, etc.)
PTS
Work Sampling
Indirect(Work Sampling)/Expense Work(어려운 문제-지식노동자) 교과서의
논리는 부적합’)
 Implementation/Follow Up, Wage Payment/Compensation,
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PowerPoint to accompany
Methods, Standards, and Work Design
12th Edition
Niebel/Freivalds
Training and Other Management Practices
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Trends in Work Management
 Survey:
 ‘Motion and Time Study’ ranked Number 1 in
1954, 1964 survey
 Team work, Job evaluation, Training
 산업별 최강자를 보자:
 10대 산업:
자동차,조선,일반기계,전자(휴대폰,가전,디스플
레이,반도체),철강,석유화학,섬유
 건설산업:
 한국은 거의 모든 분야에서 5위 이내
 What next?
3
Learning Curve Phenomenon
Reduction in cycle time that occurs in a repetitive
work activity as the number of cycles increases
 An important topic in time study
 When a worker accomplishes a task over and
over, the time required for each successive cycle
decreases as he or she learns the task
 At first the learning effect is rapid, and the cycle time
decreases significantly
 As more and more cycles are completed, the cycle time
reduction becomes less and less
Log-Linear Model
When learning curve time data are plotted on loglog coordinates, the plot yields a straight line with
slope m
y = kxm
where y = dependent variable, k = constant
representing the value of the dependent variable for
the first work cycle, x = number of work units
completed, and m = slope
ln LR 
m=
and LR = 2m
ln 2
Learning Effect(exponential decay): Log/Log Graph
(예)Learning Curve for LR = 80%
Two Widely Used Log-Linear Models
1. Crawford Model
 Dependent variable is unit time TN
2. Wright Model (Original Learning Curve Model)
 Dependent variable is cumulative average time
T
N
Crawford Model
Most widely used learning curve model in industry today
T N  T1 N
m
Example: T1 = 10 hr, LR = 80%, how long will it take to complete the 20th
work unit?
m = ln(0.80)/ln 2 = -0.32193
T20 = 10(20)-0.32193 = 3.81 hr
Total cumulative time
N
TT N  T1  i
i 1
Cumulative average time
T
N

TT N
N
m
Wright Model
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First learning curve model to be published
Based on cumulative average time per unit
T N = T1Nm
Total cumulative time:
TTN = N T N
or TTN = T1Nm+1
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Unit time:
TN = TTN - TTN-1
Comparison of Crawford and Wright
Typical Learning Rates (Crawford)
Type of work
LR, %
Assembly
84-85
Prototype assembly 65
Clerical ops
75-85
Inspection
86
Machining
90
Welding
85-90
Industry
Aerospace
Complex machines
Construction
Electronics mfg
Machine shop
Shipbuilding
LR, %
85
75-85
70-90
90-95
90-95
80-85
Worker-Machine Systems
 Learning in a work-machine system will
be a composite of the learning rates of
the two components of the system
LRw-m = pw LRw + pm LRm
where pw = proportion of cycle time
controlled by worker, and pm = proportion
of cycle time controlled by machine
Learning Loss due to Interruption
Effect of Breaks(휴가) on Learning
Other Factors Affecting Learning
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Product complexity
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LR
Preproduction planning
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More opportunities for learning - higher T1 and lower
Fewer opportunities for learning - lower T1 and higher
LR
Labor turnover - slower learning (higher LR)
Plateau model - learning curve consists of two
phases:
1. Start-up - log-linear model applies
2. Steady state - no further improvement
Plateau Learning Curve Model
Why the Plateau Model Occurs
 In a worker-machine system, worker is
finally limited by the speed of the machine
 No incentives for workers to make further
improvements
 Management is unwilling or unable to
invest in newer production technologies
that would sustain the learning curve
 Management does not believe that
learning can continue indefinitely, and this
becomes a self-fulfilling prophecy
Maslow’s Hierarchy of Human Needs(1970)
•Food, Water, Health
•Avoid Physical Injury, Nice
Supervisor
•Social Belonging, Friendship
•Achievement, Show
Competence
•Ego Satisfaction: 사람마다
다르다
Herzberg’s Motivation Maintenance Theory(1966)
 Herzberg(1966)
 Extrinsic (Hygiene) Factors: 대개 de-motivators
 Intrinsic Factors: motivator
 (예) Working Condition, Supervision, Salary,
Human Relation은 Extrinsic
 (예) Work Itself, Job Enrichment(수직), Job
Enlargement(수평)은 Intrinsic
 연령대, 교육 정도, 급여 수준 모두가 영향을
미치는 요소로 밝혀 졌다.
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Human Interaction
 Transactional Analysis
 Dale Carnegie’s Approach
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Trends in Manufacturing Industries
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Lean Manufacturing(TPS)
Total Quality Management
Total Productive Maintenance
Computer Integrated Manufacturing
Real Time Enterprises
Supply Chain Management
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결론
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과학/공학기술의 수준은 선진국의 척도
0.5차, 2.5 차 산업의 대두
인류의 지속적 성장을 위해서는 지능형 제조가 필요(인구,
환경, 소득격차,
산업공학은 공학분야 내에서 독특한 역할 담당
제조업에서의 산업공학적 Know-how는
정보화 시대, 지식 사회에도 아주 유용할 것
인류역사상 최초로 “받던 나라”에서 “주는 나라”로
가장 중요한 부분은 전공지식+따뜻한 가슴
(한국인의 약점 4C: Comm, Crea, Car, Caus…)
(한국인의 장점 4E: Endu, Edu, Emo, End..)
미래형
인재
Credit::박진우/김해중/이동명
정직, 성실