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Leadership & Management

operation managrement time management manpower calculations

Neha KajulkarFolgen

- 1. © Wiley 2010 1 Chapter 11 – Work System Design Operations Management by R. Dan Reid & Nada R. Sanders 4th Edition © Wiley 2010
- 2. © Wiley 2010 2 Learning Objectives Describe the elements of work system design and the objectives of each element Describe relevant job design issues Describe methods analysis Understand the importance of work measurement Describe how to do a time study
- 3. © Wiley 2010 3 Learning Objectives – con’t Describe how to do work sampling Develop standard times Show how to use work standards Describe compensation plans Describe learning curves
- 4. © Wiley 2010 4 Designing a Work System Designing a work system is part of developing an operations strategy Effective operations strategy provides structure for company productivity The work system includes: Job design Work measurements Worker compensation
- 5. © Wiley 2010 5 Design a Job Job Design specifies work activities of an individual or group Jobs are designed by answering questions like: What is the job’s description? What is the purpose of the job? Where is the job done? Who does the job? What background, training, or skills are required to do the job?
- 6. © Wiley 2010 6 Additional Job Design Factors Technical feasibility: The job must be physically and mentally doable Economic feasibility: Cost of performing the job is less than the value it adds Behavioral feasibility: Degree to which the job is intrinsically satisfying to the employee
- 7. © Wiley 2010 7 Machines or People - Should the Job Be Automated? 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 Need for personal customer relationships
- 8. © Wiley 2010 8 Levels of Labor Specialization Level of labor specialization can: Reduce the employee’s scope of expertise (higher levels of specialization) Increase the employee’s scope of expertise (lower levels of specialization) Work satisfaction helps define level of specialization Specialization can result in employee boredom
- 9. © Wiley 2010 9 Specialization: Management’s View Advantages: Readily available labor Minimal training required Reasonable wages costs High productivity Disadvantages: High absenteeism High turnover rates High scrap rates Grievances filed
- 10. © Wiley 2010 10 Specialization: Employee’s View 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
- 11. © Wiley 2010 11 Eliminating Employee Boredom Job enlargement Horizontal expansion of the job through increasing the scope of the work assigned. Job enrichment Vertical expansion of the job through increased worker responsibility Adding work planning or inspection to a routine assembly task Job rotation Shifting of cross trained workers to other tasks Broadens understanding and can reduce fatigue
- 12. © Wiley 2010 12 Team Approach to Job Design 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, manage, & control their assigned work flow
- 13. © Wiley 2010 13 The Alternative Workplace An alternative workplace brings work to the worker rather than the worker to the workplace 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 AT&T provides flexible workstations so workers can rotate in and out as needed
- 14. © Wiley 2010 14 Methods Analysis A detailed step-by-step analysis of how a given job is performed Can distinguish between value-added & non- value-added steps Analysis can revise the procedure to improve productivity After improvement, must revise the new standard operating procedure Follow-up to insure that changes actually improve the operation
- 15. © Wiley 2010 15 Methods Analysis Method analysis consists of: 1. Identify the operation to be analyzed 2. Gather all relevant information 3. Talk with employees who use the operation 4. Chart the operation 5. Evaluate each step 6. Revise the existing or new operation as needed 7. Put the revised or new operation into effect, then follow up on the changes or new operation
- 16. © Wiley 2010 16 Methods Analysis at FEAT Company: The methods analyst has been asked to review the transformer wiring operation because of past quality problems from poor solder joints. The solder operation sequence and the workstation layout are shown below. 1. 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
- 17. © Wiley 2010 17 Analyst’s Recommendations: A. Maize reviews the workplace layout and the present flow chart (below), and recommends reversing the solder sequence from #6-#1, which is less problematic for the right handed operator. He schedules a follow up to insure that the new method has fixed the quality problem.
- 18. © Wiley 2010 18 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
- 19. © Wiley 2010 19 Work Measurement Work Measurement helps determine how long it should take to do a job Involves determining Standard Time Standard time: the length of time a qualified worker, using appropriate processes and tools to complete a specific job, allowing time for personal fatigue, and unavoidable delays
- 20. © Wiley 2010 20 Work Measurement Standard time is used in: Costing the labor component of products Tracking employee performance Scheduling & planning required resources
- 21. © Wiley 2010 21 Setting Standard Times Step 1: Choose the specific job to be studied Step 2: Tell the worker whose job you will be studying Step 3: Break the job into easily recognizable units Step 4: Calculate the number of cycles you must observe Step 5: Time each element, record data & rate the worker’s performance Step 6: Compute the normal time Step 7: Compute the standard time
- 22. © Wiley 2010 22 How to do 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
- 23. © Wiley 2010 23 Doing a Time Study Need to determine how many observations are required Involves determining the level of accuracy required and confidence level desired n: number of observations of an element that are needed z: the number of normal standard deviations needed for desired confidence s: the standard deviation of the sample a: desired accuracy or precision x-bar: the mean of the sample observations 2 x s a z n
- 24. © Wiley 2010 24 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. ns observatio 25 0.24 0.03 0.05 1.96 x s a z n 2 2 7 1 2 3 4 5 6 7 8 9 10 A B C D E Example 11.3 Pat's Pizza Place Standard Deviation Mean Observed Revised Observed Work Element (minutes) Time (minutes) Time (minutes) # Observations 1. Get ball of dough 0.010 0.12 0.15 11 2. Flatten dough 0.030 0.25 0.25 23 3. Spin and toss dough 0.040 0.50 0.60 10 4. Place dough on counter 0.005 0.12 0.15 3 5. Pour sauce on formed dough 0.035 0.30 0.30 21 6. Place grated cheese on top 0.025 0.25 0.28 16 7. Place pepperoni on sauce 0.030 0.24 0.28 25
- 25. © Wiley 2010 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.
- 26. © Wiley 2010 26 Other Time Factors Used in Calculating Standard Time 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% 1.176 0.15 1 1 PFD 1 1 AF Work ed Tme
- 27. © Wiley 2010 27 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 13 14 15 16 17 18 19 20 21 22 A B C D E F Example 11.4 Calculating Standard Time for a Hand-Tossed Cheese and Pepperoni Pizza Revised Observed Performance Rating Frequency Normal Time Standard Time Work Element Time (minutes) Factor (minutes) (minutes) 1. Get ball of dough 0.15 0.90 1 0.135 0.159 2. Flatten dough 0.25 1.00 1 0.250 0.294 3. Spin and toss dough 0.60 0.85 1 0.510 0.600 4. Place dough on counter 0.15 1.10 1 0.165 0.194 5. Pour sauce on formed dough 0.30 1.20 1 0.360 0.423 6. Place grated cheese on top 0.28 1.00 1 0.280 0.329 7. Place pepperoni on sauce 0.28 0.95 1 0.266 0.313 Total Time 1.966 2.312
- 28. © Wiley 2010 28 Other Time Study Methods Elemental time data establishes standards based on previously completed time studies, stored in an organization’s database. Predetermined time data (e.g. MTM and MTS) is a published database element time data used for establishing standard times Reach, grasp, move, engage, insert, turn, etc. Work Sampling is a technique for estimating the proportion of time a worker spends on an activity
- 29. © Wiley 2010 29 Work Sampling Procedures 1. Identify the worker or machine to be sampled 2. Define the activities to be observed 3. Estimate the sample size based on level of accuracy and confidence level 4. Develop the random observation schedule. Make observations over a time period that is representative of normal work conditions 5. Make you observations and record the data. Check to see whether the estimated sample size remains valid 6. Estimate the proportion of the time spent on the given activity
- 30. © Wiley 2010 30 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 ns observatio 470.89 0.5 1 0.5 0.05 2.17 p 1 p e z n 2 2 ) ) 0.5 p ns observatio 302 0.2 1 0.2 0.05 2.17 n 2
- 31. © Wiley 2010 31 Compensation Compensation is the third part of work system design Time-based plans (pay based on the number of hours worked) vs. output-based systems (pay based on the number of units completed) 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?
- 32. © Wiley 2010 32 Worker Compensation Systems – con’t Group incentive plans reward employees when company achieves certain performance objectives Profit sharing – a employee bonus pool based on sharing of company’s profits Gain sharing – emphasizes cost reduction rather than profits Plans put part of a worker’s salary at risk Compensation system may undermine teamwork
- 33. © Wiley 2010 33 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 learning n = the number of times the task has doubled hours 6.26 (.85) x 12 task 16th for Hours 4
- 34. © Wiley 2010 34 Work System Design within OM: How it all fits together Work system design includes job design, methods analysis, and work measurement. Manufacturing or industrial engineers often do these activities. Job design determines exactly how the product or service will be done and is linked directly to product and process design. Based on the type of product (standard or custom) and its proposed process (mass-producing or producing one at a time), a company determines the skills set needed by its employees as well as the necessary equipment. Method analysis provides a means for evaluating different processes and materials, thus allowing a company to focus on continuous improvement. This ties in directly with a company’s total quality management (TQM) focus.
- 35. © Wiley 2010 35 WSD: How it all fits together con’t Work measurement techniques allow a company to develop standards to use as a basis for evaluating the cost and effectiveness of different methods and materials for building a product or providing a service. These time standards provide a time estimate to use as a basis for establishing detailed work schedules and for determining long-term staffing levels. These time estimates can be used as a basis for making delivery or completion-time promises to customers. Standard times are used to develop lead-time estimates, which are inputs for the MRP (material requirement planning) system as well as the MPS (master production schedule) process. Work system design provides the means for setting standards against which to compare new methods, new materials, and new designs, assures that employees know how to do their job, and provides the information needed by the company to calculate its costs.
- 36. © Wiley 2010 36 Work System Design Across the Organization Work system design affections functional areas throughout the organization Accounting calculates the cost of products manufactured, variances between planned and actual costs as well as operational efficiency Marketing uses work system design as the bases for determining led time
- 37. © Wiley 2010 37 Work System Design Across the Organization – con’t Information systems uses estimates of job duration and resources in the software for scheduling and tracking operations Human resources uses work sampling to establishes and validate hiring criteria
- 38. © Wiley 2010 38 Chapter 11 Highlights Work system design involves job design, methods or process analysis and work measurement. Job design specifies the work activities of an individual or group in support of organizational objectives 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. Technical feasibility is the degree to which an individual or group of individuals is physically and mentally able to do the job. Economic feasibility is the degree to which the value of a job adds and the cost of have the job done are profitable for the company.
- 39. © Wiley 2010 39 Chapter 11 Highlights – con’t Methods or process analysis is concerned with how the employee does the job. Methods analysis can also be used to improve the efficiency of an operation. Work measurement is used to determine standard times. A standard time is how long it should take a qualified operator, using the appropriate process, material, and equipment, and working at a sustained pace, to do a particular job. Standard times are used for product costing, process and material evaluations, and for planning workloads and staffing. Standard times are usually based on time studies. Work sampling is used to estimate the proportion of time that should be spent on an activity.
- 40. © Wiley 2010 40 Chapter 11 Highlights – con’t To do a time study, first identify the job then break the job into work elements. Finally, determine the number of observations needed and perform the observation. Work sampling involves random observations of a worker. Each time you observe the worker, you note what activity the worker is doing. After numerous observations, you can project the expected proportion of time the worker should spend on different activities. Standard times are developed with either time studies, elemental time data, or predetermined time data. You learned how to develop standard times using time studies. After conducting the time study, you compute the mean observed time for each work element. You compute the normal time for the work element by multiplying the mean observed time by the performance rating factor. You find the standard time for each work element by multiplying the normal time by the allowance factor.
- 41. © Wiley 2010 41 Chapter 11 Highlights – con’t Standard times are used to compare alternative processes, evaluate new materials or components, and evaluate individual worker performance. Standards also allow you to determine when a job should be completed or how many units can be done in a period of time. Worker compensation systems are either time-based or out-put based. Time-based systems pay the employee for the number of hours worked. Output-based systems pay the employee for the number of units completed. Compensation schemes can be based on either individual or group performance. 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. Using learning curves, you can estimate how long a particular task will take. It allows the company to schedule better and calculate cost more accurately.
- 42. 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 problems 5-10 are worth 5 points; 19 is worth 10 for a total of 40 points for the assignment.