Deck 17: Scheduling

Question 1

Job shop scheduling is also known as shop floor control.

Answer 1

True

Question 2

Explain what sequencing is and use rules and quantitative tools for optimizing the sequence of jobs processed through one or two workstations.

Answer 2

Sequencing is the process of prioritizing jobs and determining the processing order. See Section 17.3 for examples of sequencing jobs through one or two workstations.

Question 3

The process of assigning work to limited resources is known as scheduling.

Answer 3

False

Question 4

The process of prioritizing jobs that have been assigned to a resource is called sequencing.

Question 5

Scheduling specifies when labour, equipment and facilities are needed to produce a product.

Question 6

Scheduling is considered the last stage of the planning process.

Question 7

The wide variety of jobs in a job shop makes scheduling difficult.

Question 8

Job-shop scheduling is usually performed by skilled machine operators.

Question 9

Describe scheduling techniques and list the objectives of scheduling.

Question 10

Explain what loading is and use the assignment method to load work on to limited resources.

Question 11

Determining the optimal allocation of jobs to machines or workers can be solved using the assignment method of linear programming.

Question 12

Gantt charts show the planned and yet to be completed activities against total activities.

Question 13

The scheduling function for mass production and job shop production are basically the same.

Question 14

Use a heuristic to schedule workers and explain the capabilities provided by employee scheduling software.

Question 15

Sequencing involves determining the order in which jobs are released to the shop floor.

Question 16

Managers typically use multiple objectives when constructing a schedule.

Question 17

The sequence in which jobs should be processed is determined by using the linear programming.

Question 18

Use several methods to monitor the progress of jobs in a job shop environment.

Question 19

Explain the basics of finite scheduling, and use the theory of constraints procedure to schedule multiple jobs through multiple workstations.

Question 20

Minimizing overtime is one of several objectives that could be considered when constructing a schedule.

Question 21

Johnson's rule gives an optimal sequence for jobs processed serially through a two step system.

Question 22

With drum-buffer-rope (DBR), the bottleneck resource is always the buffer.

Question 23

Typically, there are more options available when scheduling employees because labour is a very flexible resource.

Question 24

Finite scheduling will not load a resource beyond its fixed capacity.

Question 25

The dispatch list contains the order in which the work is assigned to a productive resource.

Question 26

Scheduling using the theory of constraints (TOC) requires that the process batch sizes and the transfer batch sizes always match.

Question 27

The first-come, first-served (FCFS) sequencing rule should be only used when operating at high levels of capacity.

Question 28

The process of smoothing out the work assigned is known as

A) production control
B) sequencing
C) load levelling
D) dispatching

Question 29

The longest processing time (LPT) rule tends to complete larger jobs in-house when subcontracting is anticipated.

Question 30

Input/output control provides the information necessary to regulate work flow in a job shop environment.

Question 31

All sequencing rules strive to optimize both processing efficiency and due date performance.

Question 32

The assignment method of linear programming can be used for both the loading and employee scheduling.

Question 33

Increasing the capacity of a work centre that is a bottleneck increases the output.

Question 34

The process of assigning work to limited resources is known as

A) loading.
B) sequencing.
C) monitoring.
D) dispatching

Question 35

Which of the following is not typically considered an objective of scheduling?

A) minimizing job lateness
B) maximizing time in the system
C) minimizing overtime
D) maximizing machine utilization

Question 36

In a job shop environment, the process of prioritizing jobs assigned to a productive resource is called sequencing.

Question 37

The shortest processing time (SPT) rule is most useful when the job shop is not congested.

Question 38

The time required for a job to move through the system is referred to as flow time.

Question 39

Tardiness is defined as the difference between a job's flow time and makespan.

Question 40

The theory of constraints (TOC) approach to scheduling concentrates on scheduling the bottleneck resources.

Question 41

If the following jobs are sequenced according to the LPT rule, then the mean completion time (in days) for all jobs is (assume zero for today's date)

A) 118 days.
B) 6.6 days.
C) 33 days.
D) 23.6 days.

Question 42

The sequencing rule that minimizes average tardiness for a set of jobs to be processed on one machine is

A) first-come-first served (FCFS).
B) longest processing time (LPT).
C) shortest process time (SPT).
D) due date (DDATE).

Question 43

If a job is ahead of schedule, then its critical ratio (CR) will be

A) less than one.
B) greater than one.
C) equal to one.
D) none of the above.

Question 44

The process of prioritizing jobs that have been assigned to a resource is called

A) loading.
B) monitoring.
C) sequencing.
D) input/output analysis.

Question 45

If the following jobs are sequenced according to the SPT rule, then the total number of jobs that would be late is (assume zero for today's date)

A) 0 jobs.
B) 1 job.
C) 2 jobs.
D) 3 jobs.

Question 46

If the following jobs are sequenced according to the FCFS rule, then the mean tardiness (in days) for all jobs would be (assume zero for today's date)

A) 5 days.
B) 8.33 days.
C) 10.6 days.
D) 25 days

Question 47

If the following jobs are sequenced according to the SPT rule, then the mean tardiness (in days) for all the jobs is (assume zero for today's date)

A) 16 days.
B) 13 days.
C) 5.2 days.
D) 3.2 days.

Question 48

The time required to complete a group of jobs is referred to as

A) flow time.
B) makespan.
C) completion time.
D) none of the above.

Question 49

If the work remaining is greater than the time remaining, the critical ratio (CR) will be

A) less than one.
B) greater than one.
C) equal to one.
D) none of the above.

Question 50

If the following jobs are sequenced according to the first-come-first-served (FCFS) rule, then the mean completion time in days for all jobs is (assume zero for today's date)

A) 33 days.
B) 22 days.
C) 6.6 days.
D) 4.4 days.

Question 51

If the following jobs are sequenced according to the FCFS rule, then job C is completed on day (assume zero for today's date)

A) 11.
B) 17.
C) 25.
D) 30.

Question 52

If the following jobs are sequenced according to the SPT rule, then the maximum job tardiness (in days) is (assume zero for today's date)

A) 26 days.
B) 16 days.
C) 10 days.
D) 5.2 days.

Question 53

If the following jobs are sequenced according to the FCFS rule, then the total number of jobs that would be late is (assume zero for today's date)

A) 4.
B) 3.
C) 2.
D) 1.

Question 54

The sequencing rule that will minimize average job completion time for a set number of jobs to be processed on one machine is

A) first-come-first served (FCFS).
B) longest processing time (LPT).
C) shortest process time (SPT).
D) due date (DDATE).

Question 55

If the following jobs are sequenced according to the SPT rule, then the mean completion time (in days) for all the jobs is (assume zero for today's date)

A) 6.6 days.
B) 16 days.
C) 22 days.
D) 33 days.

Question 56

If the following jobs are sequenced according to the SPT rule, then job B is completed on day (assume zero for today's date)

A) 6.
B) 14.
C) 15.
D) 22.

Question 57

If the following jobs are sequenced according to the LPT rule, then the maximum job tardiness (in days) is (assume zero for today's date)

A) 7 days.
B) 10 days.
C) 20 days.
D) 25 days.

Question 58

If the following jobs are sequenced according to the LPT rule, then the mean tardiness (in days) for all jobs is (assume zero for today's date)

A) 62 days.
B) 12.4 days.
C) 15.5 days.
D) 25 days.

Question 59

If the following jobs are sequenced according to the FCFS rule, then the maximum job tardiness (in days) is (assume zero for today's date)

A) 0 days.
B) 8 days.
C) 20 days.
D) 25 days.

Question 60

Which of the following is not part of the procedure for a minimization problem under the assignment method of loading?

A) performing row reductions
B) performing column reductions
C) developing a constraint matrix
D) developing an opportunity cost matrix

Question 61

If the following jobs are sequenced according to the DDATE rule, then job A would be completed on day (assume zero for today's date)

A) 8.
B) 12.
C) 16.
D) 22.

Question 62

If the following jobs are sequenced according to the SLACK rule, then the total number of jobs that would be late is (assume zero for today's date)

A) 1 jobs.
B) 2 jobs.
C) 3 jobs.
D) 4 jobs.

Question 63

The following set of jobs must be processed serially through a two-step system. The times at each process are in hours. If Johnson's Rule is used to sequence the jobs then the makespan time (in hours) for all jobs is

A) 42 hours.
B) 53 hours.
C) 90 hours.
D) 95 hours.

Question 64

If the following jobs are sequenced according to the SLACK rule, then the mean tardiness (in days) for all jobs is (assume zero for today's date)

A) 11.25 days.
B) 7.8 days.
C) 20 days.
D) 12.5 days.

Question 65

If the following jobs are sequenced according to the SLACK rule, then job A would be completed on day (assume zero for today's date)

A) 8.
B) 7.
C) 15.
D) 12.

Question 66

Four products (1, 2, 3, and 4) must be processed on one of the four machines (A, B, C, and D). The times required in minutes for each product on each machine are shown below: If management wishes to assign products to machines so that the total time to complete all the products is minimized, then Product 3 is assigned to

A) machine A.
B) machine B.
C) machine C.
D) machine D.

Question 67

If the following jobs are sequenced according to the SLACK rule, then the maximum job tardiness (in days) is (assume zero for today's date)

A) 18 days.
B) 12 days.
C) 10 days.
D) 7 days.

Question 68

If the following jobs are sequenced according to the LPT rule, then the total number of jobs that would be late is (assume zero for today's date)

A) 5 jobs.
B) 4 jobs.
C) 3 jobs.
D) 2 jobs.

Question 69

If the following jobs are sequenced according to the DDATE rule, then the mean tardiness (in days) for all jobs is (assume zero for today's date)

A) 9.0 days.
B) 5.4 days.
C) 3.2 days.
D) 2.8 days

Question 70

If the following jobs are sequenced according to the DDATE rule, then the maximum job tardiness (in days) is (assume zero for today's date)

A) 12 days.
B) 15 days.
C) 16 days.
D) 27 days.

Question 71

If the following jobs are sequenced according to the DDATE rule, then the total number of jobs that would be late is (assume zero for today's date)

A) 5 jobs.
B) 4 jobs.
C) 3 jobs.
D) 2 jobs.

Question 72

If the following jobs are sequenced according to the SLACK rule, then the mean completion time (in days) for all jobs is (assume zero for today's date)

A) 35 days.
B) 19.4 days.
C) 18.4 days.
D) 7 days.

Question 73

Four products (1, 2, 3, and 4) must be processed on one of the four machines (A, B, C, and D). The times required in minutes for each product on each machine are shown below. If management wishes to assign products to machines so that the total time to complete all the products is minimized, then Product 4 is assigned to

A) machine A.
B) machine B.
C) machine C.
D) machine D.

Question 74

Four products (1, 2, 3, and 4) must be processed on one of the four machines (A, B, C, and D). The times required in minutes for each product on each machine are shown below: The minimum time required to complete all the products is

A) 29 minutes.
B) 27 minutes.
C) 33 minutes.
D) 36 minutes.

Question 75

Four products (1, 2, 3, and 4) must be processed on one of the four machines (A, B, C, and D). The times required in minutes for each product on each machine are shown below: If management assigns products to machines so that the total time to complete all jobs is minimized, then the time to complete Product 1 is

A) 10 minutes.
B) 9 minutes.
C) 16 minutes.
D) 12 minutes

Question 76

The following set of jobs must be processed serially through a two-step system. If Johnson's Rule is used to sequence the jobs, then the order in which the jobs would be performed is

A) A-B-C-D-E
B) C-B-E-D-A
C) E-B-D-A-C
D) D-E-B-A-C

Question 77

If the following jobs are sequenced according to the LPT rule, then job D would be completed on day (assume zero for to day's date)

A) 5.
B) 25.
C) 30.
D) 33.

Question 78

Four products (1, 2, 3, and 4) must be processed on one of the four machines (A, B, C, and D). The times required in minutes for each product on each machine are shown below: If management wishes to assign products to machines so that the total time to complete all the products is minimized, then Product 1 is assigned to

A) machine A
B) machine B
C) machine C
D) machine D

Question 79

The scheduling rule that minimizes the makespan time for a set of jobs that must be processed through a two-step system where every job follows the same sequence through the two processes is the

A) shortest processing time (SPT).
B) Johnson's Rule.
C) assignment method.
D) minimal slack rule.

Question 80

If the following jobs are sequenced according to the DDATE rule, then the mean completion time (in days) for all jobs is (assume zero for today's date)

A) 16.4 days.
B) 22.6 days.
C) 28.7 days.
D) 33.0 days