MG390 Chapter 11

Consider a three sequentially stepped process named as Process A, Process B and Process C. Input comes into Process A. Output form A goes into Process B. Output from B goes into Process C. Output of C is the final output. Suppose that it takes 2 minutes per unit in Process A, 3 minutes per unit in Process B and 1 minute per unit in Process C. What will be maximum steady state output from this system?

20 per hour Process A takes 2 minutes per unit and hence can process (60/2) = 30 units 30 per hour. Process B can process only (60/3) = 20 per hour. Process C can handle (60/1) = 60 units per hour. Hence the steady state output from this system is the smallest of the three, that is 20 per hour.

A bottleneck occurs when a stage in a production process is starving.

False A bottleneck is the activity in a process that limits the overall capacity of the process.

To reduce process flow time, you might try which of the following actions?

All of these areCorrect: (Reduce interruptions. Perform activities in parallel. Change the sequence of activities. Acquire additional equipment.)

To reduce process throughput time, you might try which of the following actions? A.Outsource activities. B.Improve teamwork. C.Reduce management interference. D.Introduce incentive pay E.Change the sequence of activities.

Change the sequence of activities. Following are some suggestions for reducing the flow time of a process that do not require the purchase of new equipment. Often, a combination of ideas is appropriate. (Note that acquiring new equipment can also reduce flow time.) Perform activities in parallel. Change the sequence of activities. Reduce interruptions.

Make-to-order production processes are well suited for high-volume production of a standardized product.

False A highly efficient make-to-stock process that produces standard products that can be delivered quickly.

Process analysis can help answer many important questions such as why change in a process is necessary.

False Analyzing a process allows some important questions to be answered, such as these: How many customers can the process handle per hour? How long will it take to serve a customer? What change is needed in the process to expand capacity?

A diamond is conventionally used in a process flowchart to represent a storage area or queue.

False Decision points are depicted as a diamond with the different flows running from the points on the diamond.

When a make-to-order production process is used, production is based on forecasts.

False Make-to-order process is activated only in response to an actual order.

Make-to-stock production processes can easily handle requests for customized product features.

False Make-to-stock production processes are highly efficient processes that produce standard products that can be delivered quickly.

The long-term relationship among the inventory, throughput, and flow time of a production system in steady state is called which of the following?

Little's law

Which of the following production process terms best describes the situation when activities in a stage of production must stop because there is no work? Multiple Choice Setup time Buffering Buffer Starving Blocking

Starving Starving occurs when the activities in a stage must stop because there is no work.

Benchmarking refers to the practice of comparing the production metrics of one firm with the production metrics of another.

True Comparing the metrics of one firm to another, often referred to as benchmarking, is an important activity.

Efficiency of a production process is the ratio of the actual output of a process to some standard.

True Efficiency is a ratio of the actual output of a process relative to some standard.

Hybrid processes combine features of make-to-order and make-to-stock production processes.

True In general, hybrid processes combine the features of both make-to-order and make-to-stock.

Job design is defined as the function of specifying the work activities of an individual or group in an organizational setting.

True Job design may be defined as the function of specifying the work activities of an individual or group in an organizational setting.

Productivity in a production process can be measured by the ratio of output to input.

True Productivity is the ratio of output to input.

Consider a three sequentially stepped process named as Process A, Process B and Process C. Input comes into Process A. Output form A goes into Process B. Output from B goes into Process C. Output of C is the final output. Suppose that it takes 2 minutes per unit in Process A, 3 minutes per unit in Process B and 1 minute per unit in Process C. Suppose further that Process A receives input at the rate of 30 per hour. Where would you place a buffer? a. in front of Process C b.None c.in front of Process A d.in front of Process B e.in front of both Process B and Process C

d. in front of process B Process A takes 2 minutes per unit and hence can process (60/2) = 30 units 30 per hour. Process B can process only (60/3) = 20 per hour. Process C can handle (60/1) = 60 units per hour. Hence you must place a buffer in front of Process B.

Run time is calculated by multiplying the number of units in a batch by the setup time.

False Run time is the time required to produce a batch of parts. This is calculated by multiplying the time required to produce each unit by the batch size.

A service operation by its very nature is a make-to-stock type of production process.

False Services by their very nature often use make-to-order processes.

Cycle time is the ratio of the time that a resource is actually activated relative to the time that it is available for use.

False The cycle time of a repetitive process is the average time between completions of successive units.

Throughput rate of a production process is the amount of time a unit spends actually being worked on.

False The throughput rate is the output rate that the process is expected to produce over a period of time.

Which of the following terms describes the time a unit spends actually being worked on together with the time spent waiting in a queue?

Flow time Flow time includes the time that the unit spends actually being worked on together with the time spent waiting in a queue.

A process flowchart uses symbols to represent which of the following? Flows of material or customers Factory location Data analysis Warehouse space available Workforce schedules

Flows of material or customers

According to Little's law, which of the following ratios is used to find flow time? Multiple Choice Process velocity/Throughput time Cycle time/Process time Value-added time/Process velocity Inventory/Throughput rate Throughput time/Process velocity

Inventory/Throughput rate Little's law says there is a long-term relationship among the inventory, throughput, and flow time of a production system in steady state. The relationship is: Inventory = Throughput rate × Flow time. Hence, Flow time = Inventory/Throughput rate.

The long-term relationship among the inventory, throughput, and flow time of a production system in steady state is called which of the following? Multiple Choice Murphy's law Little's law Peterson's rule Robert's rule None of these

Little's Law Little's law says there is a long-term relationship among the inventory, throughput, and flow time of a production system in steady state.

Explanation Item 9 Item 9 1 of 1 points awarded Item Scored Consider a three sequentially stepped process named as Process A, Process B and Process C. Input comes into Process A. Output form A goes into Process B. Output from B goes into Process C. Output of C is the final output. Suppose that it takes 2 minutes per unit in Process A, 3 minutes per unit in Process B and 1 minute per unit in Process C. Suppose further that Process A receives input at the rate of 30 per hour. Which process will be experiencing starving?

Process C

A process flowchart uses which of the following symbols to represent tasks or operations in a flow diagram? Inverted triangle Diamond Rectangle A dashed line Arrow

Rectangle

According to Little's law, which of the following can be used to estimate inventory? Multiple Choice Value-added time/Process velocity Set up time/Throughput rate Process velocity/Flow time Process time/Cycle time Throughput rate ×Flow time

Throughput rate ×Flow time Correct Little's law says there is a long-term relationship among the inventory, throughput, and flow time of a production system in steady state. The relationship is: Inventory = Throughput rate × Flow time.

A triangle is conventionally used in a process flowchart to represent a storage area or queue.

True The storage of goods or other items (are represented) as inverted triangles.

Inventory turn is a better measure than the total value of inventory for comparative purposes because it is a relative measure.

True A better measure than the total value of inventory is inventory turn. Because inventory turn scales the amount of inventory by dividing by the cost of goods sold, this provides a relative measure that has some comparability.

When we use a make-to-stock production process, we control our production based on a desired amount of finished goods inventory.

True A make-to-stock process can be controlled based on the actual or anticipated amount of finished goods inventory.

Buffering in a production process refers to a storage area between stages of production activity where output of a stage is placed prior to being used in a "downstream" stage.

True A multiple-stage process may be buffered internally. Buffering refers to a storage area between stages where the output of a stage is placed prior to being used in a downstream stage. Buffering allows the stages to operate independently.

A "process" is any part of an organization that takes inputs and transforms them into outputs that, hopefully, are of greater value to the organization than the original inputs.

True A process is any part of an organization that takes inputs and transforms them into outputs that, it is hoped, are of greater value to the organization than the original inputs.

Process analysis can help answer many important questions such as how many customers can a process handle per hour.

True Analyzing a process allows some important questions to be answered, such as this: How many customers can the process handle per hour?

If you want to reduce process flow time, it has been suggested that you can reduce interruptions in the production process.

True Many processes are performed with relatively large time intervals between the activities. For example, purchase orders may be issued only every other day. Individuals preparing reports that result in purchase orders should be aware of deadlines to avoid missing them, because improved timing in these processes can save many days of flow time.

Pacing in production processes refers to the fixed timing of the movement of items through the process.

True Pacing refers to the fixed timing of the movement of items through the process.

If you want to reduce process flow time, it has been suggested that you can perform activities in the process in parallel.

True Perform activities in parallel. Most of the steps in an operations process are performed in sequence. A serial approach results in the flow time for the entire process being the sum of the individual steps plus transport and waiting time between steps. Using a parallel approach can reduce flow time by as much as 80 percent and produces a better result.

Process velocity is the ratio of the total throughput time to the value added time.

True Process velocity (also known as throughput ratio) is the ratio of the total throughput or flow time to the value-added time. Value-added time is the time in which useful work is actually being done to the unit.

Setup time is the time required to prepare a process to produce a particular item.

True Setup time is the time required to prepare a machine to make a particular item.

A rectangle is conventionally used in a process flowchart to represent a task or operation.

True Tasks are shown as rectangles.

Methods Time Management (MTM) and Most Work Measurement System (MOST) are proprietary examples of predetermined motion-time data systems (PMTSs).

True The two indirect methods are predetermined motion-time data systems (PMTS), which sum data from tables of generic movement times developed in the laboratory to arrive at a time for the job (the most widely used are proprietary systems—Methods Time Measurement [MTM] and Most Work Measurement System [MOST]), and elemental data, which sums times from a database of similar combinations of movements to arrive at job time.