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Chapter 11 – Work System Design
Operations Managementby
R. Dan Reid & Nada R. Sanders2nd Edition © Wiley 2005
Work System Design Designing a work system is part of
developing an operations strategy The work system includes:
Job design Work measurements Worker compensation
Job Design Definition: specification of the work
activities for an individual or group within an organizational setting.
Behavioral factors: Degree of labor specialization (advantages,
disadvantages). Job enlargement (vertical/horizontal) and job
enrichment. Physical considerations:
Work-task continuum.
Job Design Feasibility Issues
Technical feasibility: Whether the job is within physical &
mental capabilities of the workforce Economic feasibility:
Whether the cost of performing the job is less than its added value
Behavioral feasibility: Whether the job is intrinsically satisfying
Job Design (Trends) Quality at the source. Cross-training—multi-functional
workers. Employee involvement/creation of
teams. Feedback systems. Outsourcing tasks. Automation Meaningful/rewarding jobs.
Workplace Changes Labor/organizational changes.
More technology, fewer workers and organizational layers.
Increased employee involvement. Composition (gender/ethnic diversity). Thus, managers have different roles.
Mentors or coaches rather than “bosses.”
Employee Empowerment Assume roles once owned by managers. Increases employee motivation and hence
productivity. Managers must share:
Organizational performance information. Rewards (based on organizational
performance). Knowledge/expertise needed to enhance
organizational performance. Decision-making power.
Involvement Increases trust and commitment Improves employee communications
and attitudes Involved employees are more likely to
generate new ideas Involved employees achieve a higher
quality of work life which generates higher levels of commitment leading to higher productivity
Approaches to Involving Employees
Must be long-term, ongoing attempts Communications efforts
feedback “bottom-up” communications
attitude survey feedback suggestion systems team building and quality circles
Teamwork Teams often outperform individuals. Self-managed teams have been found
to increase organizational performance. Responsible for many managerial actions:
Work assignments. Work pace. Quality assessment. Hiring/firing.
Cross-functional work teams (projects, committees).
Use of Teams Problem-solving teams:
Small groups, trained in problem-solving techniques. Used to identify, analyze, & propose solutions to workplace problems
Special-purpose task forces: Highly-focused, short-term teams with a
focused agenda (often cross-functional) Self-directed or self-managed teams:
Team members work through consensus to plan, mange, & control their assigned work flow
QWL: Definition II “Quality of work life emphasizes improving
the human dimension of work.” HR should try to improve QWL “by:
introducing participative problem solving, restructuring work, introducing innovative reward systems, improving the work environment.”
[Source: Wheelen and Hunger, 2000, p. 99]
Work/Life Issues: State of Utah Dept. of Workforce Services
“Successful work/life programs can have a tremendous bottom-line business impact by: Reducing turnover. Enhancing recruitment. Reducing absenteeism. Improving retention. Improving productivity. improving morale. Strengthening employee commitment.
Work/Life Elements Child care. Elder care. Employer efforts. Health & wellness. Parenting/fathering. Recruiting/retention Telecommuting. The workplace. Work/life balance. [Source:
http://occ.dws.state.ut.us/WorkLife/dwsdefault.asp]
Job Characteristics Theory(Hackman and Oldham, 1976)
Critical Psychological States: experience meaningfulness of the work experience responsibility for work outcomes knowledge of results
Core task dimensions skill variety task identity task significance autonomy feedback
Automation: Factors to Consider
Safety & risk of injury to workers Repetitive nature of the task
(monotonous?) Degree of precision required Complexity of the task Need for empathy, compassion, or
other emotional elements Customer acceptance of automation
Management’s View of Labor Specialization
Advantages: Minimal training
required Reasonable wages
costs High productivity Readily available
labor
Disadvantages: High absenteeism High turnover rates High scrap rates High number of
employee grievances filed
Employee’s View of Labor Specialization
Advantages: Minimal credentials
required Minimal
responsibilities Minimal mental
effort needed Reasonable wages
Disadvantages: Boredom Little growth
opportunity Little control over
work Little room for
initiative Little intrinsic
satisfaction
Eliminating Employee Boredom
Job enlargement Horizontal expansion of the job by increasing the
scope of the work assigned Enhances pride of work and sense of
accomplishment, but reduces productivity Job enrichment
Vertical expansion of the job by increased worker responsibility—planning and inspecting
Adds sense of control and enhances sense of pride
Job rotation Shifting of cross trained workers to other tasks Broadens understanding and can reduce fatigue
Alternative Workplaces Alternative workplaces are made possible by technologies like email, e-networks, cell
phones, & video conferencing. Current situation: More than 30 million employees work in
alternative workspaces A survey at IBM reveals that 87% of alternative
workplace employees believe their effectiveness has increased significantly
Sun Microsystems gives many of its designers the option to work at home
GE sales people work from home and hotel offices
Financial Incentive Plans Basic compensation systems: hourly pay,
straight salary, piece rate, commissions. Individual/group plans:
Performance is rewarded based on measures of output (similar to piece rates) and/or measures of quality.
“pay for knowledge.” Organizational plans:
Profit sharing. Gain sharing (based on costs/outputs,
participative management). Scanlon Plan: rewards employees for organizational
improvements.
Work Methods Studies Individual/group operations: use
charting (operations charts, worker-machine charts, simultaneous motion charts, activity charts) with time studies or standard time data to analyze/evaluate work efficiency.
Overall operations: identify non-value-adding (waste) and inefficient activities for process/productivity improvement
Study the Job1. Picks up wire in left
hand and moves it to the terminal
2. Simultaneously picks up solder iron in right hand and moves to the terminal
3. Solders wire to terminal and replaces solder iron in holder
4. Solders terminal #1, then
#2 - #6, going right to left
Importance of the Work Environment
Working conditions can effect worker productivity, product quality, and worker safety
Temperature, ventilation, noise, and lighting are all factors in work system design
Congress passed OSHA in 1970 to mandate specific safety conditions that must be met
The Americans with Disabilities Act also outlines reasonable workplace accommodations that industry must make in hiring people with some limitations
Work Measurement Standard time:
The length of time a qualified worker, using appropriate tools & procedures, will take to complete a job
Standard time is used in: Costing the labor component of products Tracking employee performance Scheduling & planning required
resources
Setting Standard Times Step 1: Choose the specific job to be studied Step 2: Inform the worker of the study Step 3: Break the job into distinguishable
elements Step 4: Calculate the number of cycles to
observe Step 5: Time each element, record data &
rate the worker’s performance Step 6: Compute the standard time
Doing a Time Study When making a time study
several decisions are made to assure desired results:
# of observations to make Desired level of accuracy Desired level of confidence
for the estimated standard time
Desired accuracy level is typically expressed as a % of the mean observed times
In next column is a formula for determining the number of observations needed
n: number of observations z: provides desired statistical
confidence (e.g.: 1.96 for 95%) s: observed standard deviation
in time required to complete the task element
a: desired accuracy or precision
x-bar: the mean observed time to complete the task
2
x
s
a
zn
Pat’s Pizza Place: Pat hires an analyst to determine a standard time to prepare a large pepperoni and cheese pizza. He takes 10 observations of the 7 elements and calculates the mean time and the standard deviation per element. He must then calculate the # of observations to be within 5% of the true mean 95% of the time.
The analyst must calculate the observations for each element to determine how many additional observations must be taken. The maximum number of 25 (in this case) for element #7 means that an additional 15 observations must be made and then the observed times are revised.
nsobservatio 250.24
0.03
0.05
1.96
x
s
a
zn
22
7
1
2
3
456789
10
A B C D EExample 11.3 Pat's Pizza Place
Standard Deviation Mean Observed Revised Observed Work Element (minutes) Time (minutes) Time (minutes) # Observations1. Get ball of dough 0.010 0.12 0.15 112. Flatten dough 0.030 0.25 0.25 233. Spin and toss dough 0.040 0.50 0.60 104. Place dough on counter 0.005 0.12 0.15 35. Pour sauce on formed dough 0.035 0.30 0.30 216. Place grated cheese on top 0.025 0.25 0.28 167. Place pepperoni on sauce 0.030 0.24 0.28 25
Other Time Factors Used in Calculating Standard Time
The normal time (NT) is the mean observed time multiplied by the performance rating factor (PRF)
The PRF is a subjective estimate of a worker’s pace relative to a normal work pace
The frequency of occurrence (F) is how often the element must be done each cycle.
NT=(OT)(PRF)(F) The allowance factor (AF) is the amount of time allowed
for personal, fatigue, and unavoidable delays Standard Time=normal time x allowance factor,
where:
(NT)(AF)ST
117.6%1.1760.151
1
PFD1
1AF WorkedTme
Calculating Normal Time and Standard Time at Pat’s Pizza
The standard time for preparing a large, hand-tossed pepperoni pizza is 2.312 minutes. This means that a worker can prepare 207 pizzas in an 8-hour shift (480 minutes divided by 2.312 minutes)
12
1314
1516171819202122
A B C D E FExample 11.4 Calculating Standard Time for a Hand-Tossed Cheese and Pepperoni Pizza
Revised Observed Performance Rating Frequency Normal Time Standard TimeWork Element Time (minutes) Factor (minutes) (minutes)
1. Get ball of dough 0.15 0.90 1 0.135 0.1592. Flatten dough 0.25 1.00 1 0.250 0.2943. Spin and toss dough 0.60 0.85 1 0.510 0.6004. Place dough on counter 0.15 1.10 1 0.165 0.1945. Pour sauce on formed dough 0.30 1.20 1 0.360 0.4236. Place grated cheese on top 0.28 1.00 1 0.280 0.3297. Place pepperoni on sauce 0.28 0.95 1 0.266 0.313
Total Time 1.966 2.312
Other Time Study Methods
Elemental time data for typical work elements from previously completed time studies can be stored in a data base for use on future similar studies.
Predetermined time data (e.g. MTM and MTS) is a larger database of valid work element times used to set standards for common job elements Reach, grasp, move, engage, insert, turn, etc.
Work Sampling is a technique for estimating the proportion of time a worker spends on an activity
Work Sampling Procedure Identify the worker or machine to be
sampled Define the activities to be observed Estimate the sample size based on level of
accuracy and confidence level Develop the random observation schedule.
Make observations over a time period that is representative of normal work conditions
Observe, record data, and check to see if the estimated sample size remains valid
Estimate the proportion of the time spent on the given activity
Work Sampling Example: We are interested in estimating the proportion of time spent by secretaries arranging and scheduling travel. We are considering the possibility of bringing an on site travel agency to free up secretaries from this time consuming task. We estimate that the proportion might be as high as .50.
Step 1 – We need to estimate the number of observations needed to provide an estimate with 97% confidence (z=2.17), and the resulting estimate will be within 5% of its true value. We use
Step 2 – Based on the first 30 observations the secretary was making travel reservations 6 times (6 out of 30 observations = 0.2). With this new estimate, recalculate the sample size needed .
Final Step – After making the 302 observations, the secretary was making reservations 60 times or 19.9%. This estimate can now be used to make the decision on savings that might result by consolidating this task with an in house travel agency
nsobservatio 470.890.510.50.05
2.17p1p
e
zn
22
0.5p
nsobservatio 3020.210.20.05
2.17n
2
Worker Compensation Systems
Compensation is the third part of work system design
Time-based plans (day pay) versus output-based systems (incentive pay)
Group incentive plans: profit sharing & gain sharing
Plans put part of a worker’s salary at risk Does the compensation system undermine teamwork? Does plan prevent free-riders not doing their fair share? Does the incentive plan encourage workers to support the
long-term health of the organization?
Learning Curves When the number of times the
task is repeated doubles, the
time per task reduces as shown
in the graph
With an 85% learning curve rate,
the 2nd time a task is done will
take 85% of the 1st time.
The 4th time will take 85% of the
2nd
If an employee took 12 hours to
complete an initial task, how long
will the 16th time take (4th
doubling)
T x Ln = time required to perform a task the nth time
T = the time required to perform the task the first time
L = the rate of learningn = the number of times the
task has doubled
hours 6.26(.85)x 12task 16thfor Hours 4
Chapter 11 Highlights Work system design involves job design, work
measurements, and worker compensation. Relevant job design issues include design feasibility,
the choice of human or machine, the use of teams, and the location where the work is to be done.
Methods or process analysis is concerned with how the employee does the job and is used to make improvements.
Work measurement is used to determine standard times and are usually based on time studies. Standard times are used for product costing, process evaluations, and for planning workloads and staffing.
Chapter 11 Highlights (Continued)
Doing a time study requires breaking the job into work elements and determining the number of observations.
Work sampling involves random observations of a worker to determine the proportion of time spent on each activity.
Standard times are developed with time studies, elemental time data, and predetermined time data.
Worker compensation systems are time-based or out-put based and can be based on individual or group performance.
Learning curves show the rate of learning that occurs when an employee repeats the same task over time.
Chapter 11 Homework Hints
11.5: calculate normal time (NT) 11.6: use NT from 11.5 and allowance factor—job time
[AFJOB] to calculate standard time (ST) 11.7: use the total ST from 11.6 to calculate the
number of units. 11.8: use NT from 11.5 and allowance factor—time
worked [AFTIME WORKED] to calculate ST 11.9: use the total ST from 11.8 to calculate the
number of units. 11.10: check the book for help in finding “other
factors” to choose between the two models calculated above.
11.19: refer to example 11.6 and use table 11-9 for data to calculate the time based on the learning curve.
Note that each problem is worth 5 points for a total of 35 points for the assignment.