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Purpose of Work Study
1. To improve worker health & safety
2. To improve productivity in industry
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Objectives
• Design job/workplace to fit the human
• Measure the job with a time study
• Motivate workers to be efficient and safe
• Understand professional and ethical
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responsibility
Understand the impact of engineering
solutions in a global and societal context
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The Industrial Revolution
• The change from an agriculture- to a
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manufacturing-based society
The keyword is change
Prior to that that time, there had been
good times and bad times, but the overall
standard of living was no better in 1700
than it had been in 1000 or in Roman
times
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Improved Living Standards
• Increased knowledge
• Diffusion of knowledge
• Freedom from war
• Capital
• A development orientation
• A large market
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Increased Knowledge
• Knowledge is cumulative.
• Knowledge diffuses.
• The general trend is upward.
• Many innovations require developments in
related fields. For example, the cell phone
required the development of mainframe
computers to process the information as
well as miniaturized electronics.
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Diffusion of Knowledge
• Literacy and education are essential.
• Mass-production of knowledge
– Invention of printing
– Development of libraries
– Wide distribution of professional journals
• Increasing years of schooling in the last century
• The Internet only became popular in the 1990s
• Television’s impact on education of the
population began within the last few generations
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Freedom from War
• The Industrial Revolution began in the
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United Kingdom and United States.
Political stability
No invasions
Wars fought on foreign soil
Military spending was a low percentage of
GNP
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Capital
• In the England of 1750 to 1850: Capital from
work of the poor and colonies
• United States’ advantages:
– Virgin country
– Natural resources
– Immigrant labor
• Needed on continuing basis
• Standard of living depends on availability of
capital
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A Development Orientation
• A country must want to become
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developed.
No entrenched status quo
Democracy
Private enterprises become independent
sources of decision making
“The inherent vice of capitalism is the
unequal sharing of blessings while the
inherent virtue of socialism is the equal
sharing of miseries'.”
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A Large Market
• Many developments require a large
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customer base.
Limitations:
– Technology (transportation: land transport
and horseshoes)
– Politics (trade barriers: The British Empire)
– Participation in international trade is closely
associated with economic growth.
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Technological Society’s key
concepts
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specialization of labor
energy from machines
standardization and interchangeable parts
use of machines
mass production and mass consumption
assembly line
computers
computer networks
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1. Specialization of Labor
• Degree of specialization has increased.
• All jobs have become specialized
– Engineers
– Teachers
– Farmers
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2. Energy from Machines
• 1776: Invention of steam engine
• Electric motor
• Internal combustion engine
• Computer: mental effort
• Modern communication: communication
with the masses
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3. Standardization and
Interchangeable Parts
• Interchangeable parts
– Require accurate machine tools.
– Began in 1820s – 1850s and spread gradually.
• Standardization
– Reduces number of choice available
– Can reduce production costs
– Is often opposed by sales departments
– The Japanese versus The Detroit approach
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4. Use of Machines
• Machines reduce the effect of distance on
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transport and communication.
In production, electric motors and
computers have replaced human labor.
Humans are now the supervisors of
machines.
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5. Mass Production
and Mass Consumption
• Are interdependent.
• High productivity permits high wages.
• High wages allow workers to purchase
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products.
High sales volumes permit high wages.
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6. The Assembly Line
• Product moves past stationary machines
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and workers.
Sequence of operations is standardized.
Machines are specialized.
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7. Computers
• Developed in 1940s
• Stored programs (processor and memory)
• Transistor
• Constantly increasing speed and
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decreasing cost
Make machines more flexible and free
workers to supervise
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8. Information and
Communications Networks
• One-to-many networks (radio, TV): N
Sarnoff’s Law
• Many-to-many networks (telephones): (N2 –N)/2
Metcalfe’s Law
• The Internet: 2N – N – 1
Reed’s Law
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• Mobile phones, hand-held computers
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connected to the Internet
Virtual offices
International interaction
Direct computer-to-computer interaction
(e-commerce)
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Contributors to Technology
• Scientists and engineers
• Poets, artists, and writers
Who are the people who have really
changed our lives?
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The 1700s
• The steam engine (Watt)
• Accurate machine tools (Maudslay)
• Interchangeable parts (Whitney)
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1800 – 1850
• The dynamo (Faraday)
• The electric motor (Faraday)
• Discoveries in electricity and magnetics
• The assembly line (Colt)
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1850 – 1900
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The internal combustion engine (Otto)
Electric illumination (Edison)
The telephone (Bell)
Machine computation (Hollerith)
Scientific study of work (Taylor)
– What is the best way to do this job?
– Application of the principles of science to improving
jobs
– He noticed that with a constant-volume shovel the
load was only 3.5 lbs when shoveling rice coal but 38
lbs when shoveling ore
– Maximum material was shoveled per day when the
load on the shovel was 21.5 lbs
– The same amount of work was done with 140 men
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instead of 400-600 men
The 20th Century
• The automobile (Ford)
• Mass consumption/high worker pay (Ford)
• Motion study (Gilbreths)
– Bricklaying
– The number of motions/brick was reduced from 18
to 4.5
– Bricklayers laid 350 bricks/hr while the previous record for this
type of construction had been 120 bricks/hr.
• Triode (de Forest)
• Integrated software (Microsoft/Apple)
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•Work Smart, Not Hard
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Productivity
• Definition: Producing more output for the
same input.
• Benefits:
– Improved standard of living
– Shorter work hours and earlier
retirement
– Better education
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Components of Productivity
• Labor
• Materials
• Energy
• Information
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Classic Factors
• Land: Using better seed to grow 10% more
corn/acre or better trees
• Materials: The use of a non-corrosive material to
extend the life of a bridge
• Machines: Using e-mail rather than regular mail
• Labor: Improvement in the work methods of a
nurse to permit attending to more patients
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Measuring
Standard of Living
Gross domestic product/capita = Hourly
gross domestic product/capita X Hours
worked/year/capita
45 x 240 x 7.5 = 81,000 h/lifetime
Productivity is the product of working smart
and working hard.
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Who should benefit from increased
productivity?
– Workers (higher wages)
– Society (lower prices)
– Person who risks capital (higher profits)
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Causes of Low Productivity
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Extra work content:
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Poor product design
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Restaurant example
• Automation
• Fast food
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Improper design: Design for easy maintenance
Non-standardization: Use standard materials and parts
• Splits the production volume
• Increases paperwork
• Supply of spare parts becomes more expensive and difficult
Incorrect quality standards
• Low quality: Plastic part versus metal part
• Too-high quality: Using precision threads when standard threads are sufficient
Material wastage: An office form might use a large sheet of paper when a small piece would do
Energy wastage: Standard electrical motor used in place of a high-efficiency motor
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Poor
Poor
Poor
Poor
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Too many product models
Poorly designed product: The product may not be designed to withstand the stresses of normal use
Poor production scheduling
Poor maintenance
Poor safety and health
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Poor methods
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Poor management
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Poor workers
macro method: Data being entered by hand instead of by scanner and bar code
micro method: The wrong type or size of screwdriver
arrangement: Machines are arranged in a job-shop layout when a flow-line arrangement is better
equipment use: Training is important
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Working Smart
• Potential improvement for working hard: About 20%
• Potential improvement for working smart: Unlimited
– Pegboard task
• A: “Work at a pace you can maintain for 8 hrs; assume you are paid
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by hr.” 1.02 min.
B: “Work at a pace you can maintain for 8 hrs; assume you are paid
by the piece” 0.81 min.
C: reduce the excess work content 0.41 min.
– Better product design
– Better manufacturing methods
– Better management
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