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ch16 Student: _ "Flow-shop scheduling" is used in high volume systems True False Line balancing is a major factor in the design and scheduling of low volume systems because of batch processing True False Scheduling in intermediate-volume systems has three basic issues: run size, timing, and sequence True False When operations are often bottlenecked, additional planned idle time will improve the throughput in those areas True False When orders exceed our capacity, priority rules are used to select which orders will be accepted True False The term loading, as used in scheduling, refers to choosing the order in which jobs will be processed in lowvolume systems True False Loading is the determination of which work centers should perform which jobs True False A Gantt chart is a basic scheduling tool but works best for high-volume systems True False A Gantt chart is a basic scheduling tool that is most useful in low-volume systems True False 10 A schedule chart depicts the loading and idle times for a group of machines or departments True False 11 The output of the system cannot exceed the output of the bottleneck operation(s) True False 12 The elimination of idle time on both bottleneck and non-bottleneck operations must be accomplished to optimize output True False 13 As long as the bottleneck operations are used effectively idle time in non-bottleneck operations will not affect the overall productivity of the system True False 14 The quantity sent to a bottleneck operation could be split into two or more process batches to better utilize a bottleneck resource rather than process the entire batch True False 15 Splitting a large lot after one operation beyond a bottleneck operation would reduce the overall waiting time of the bottleneck operation True False 16 Input/output (I/O) control refers to monitoring the productivity changes since productivity is determined by the ratio of Output to Input True False 17 Infinite loading and finite loading are two major approaches used to load work centers True False 18 A schedule chart can be used to monitor job progress True False 19 The assignment model seeks an optimum matching of tasks and resources True False 20 Sequencing is concerned with the order in which jobs are done, while loading is concerned with assigning jobs to work centers or workstations True False 21 Priority rules are widely used to sequence jobs in high-volume systems True False 22 The assignment method is limited to a maximum of two jobs per resource True False 23 Priority rules generally assume that job setup cost is independent of processing sequence of jobs True False 24 In a single work center, makespan improvement can be accomplished by selecting the optimal sequencing rule True False 25 Priority rules are used in low-volume systems to identify an optimal processing sequence True False 26 The SPT priority rule always results in the lowest average completion time True False 27 Bottlenecks may shift with the passage of time, so that different operations become bottleneck operations at different times True False 28 If optimal sequencing through three work centers is desired, Johnson's Rule II is used rather than Johnson's Rule True False 29 In the decision-making hierarchy, scheduling decisions are the final step in the transformation process before actual output occurs True False 30 Makespan is the total time needed to complete a group of jobs True False 31 The theory of constraints has a goal of maximizing flow through the entire system True False 32 A major disadvantage of the SPT rule is that it tends to make very short jobs wait for a long time while longer, more important jobs are processed True False 33 The SPT rule minimizes idle time for subsequent operations True False 34 Johnson's rule is a technique used to sequence jobs through a two-step work sequence True False 35 A basic difference between scheduling in service systems and scheduling in manufacturing systems is the random nature of requests in manufacturing systems as opposed to more uniform requests in service systems True False 36 Batch process helps maximize worker efficiency True False 37 Because scheduling is a matter of detailed execution, it has little impact on the operations strategy of an organization True False 38 Scheduling pertains to: A hiring workers B process selection C buying machinery D timing the use of specific resources E determining the lowest cost 39 Which of the following is the last step in the capacity/scheduling chain? A product planning B process planning C capacity planning D aggregate planning E scheduling 40 Which of the following is not an example of a high-volume system? A aircraft manufacturing B magazine printing C petroleum refining D waste treatment E commercial donut baking 41 Which of the following is not usually a characteristic of successful high-volume systems? A smooth workflow through the system B customized output C rapid repair of breakdowns D minimal quality problems E reliable supply schedules 42 Primary considerations in scheduling high-volume systems involve: (I) coordinating the flow of inputs (II) overcoming the disruptions to planned outputs (III) assigning workers to work centers A I and III B I and II C II and III D I, II, and III E II only 43 Organizations with fixed, perishable capacity can benefit from _ A Yield Management B Price increases C Constraints D Sub-optimization E Waiting lines 44 A work center can be a _ A machine B group of machines C department D facility E all of the above 45 The EDD priority rule usually does well with regard to _ A Cost B Lateness C Overtime D Waste E Makespan 46 Which of the following is not an assumption of priority rules? A The set of jobs is known: no new jobs arrive after processing begins B Setup time is independent of processing sequence C Finite loading is assumed D Processing times are deterministic E No machine breakdowns are assumed 47 The two different approaches to load work centers in job-shop scheduling are: A load charts and schedule charts B Gantt charts and assignment method C infinite loading and finite loading D linear programming and makespan E none of the above 48 The priority rule which will sequence jobs in the order they are received is _ A EDD B LIFO C SPT D CR E FCFS 49 A scheduling technique used to achieve an optimum, one-to-one matching of tasks and resources is: A the assignment method B Johnson's rule C the optimum production technology method (OPT) D the appointment method E the reservation method 50 In a task assignment situation, in how many different ways can five jobs be assigned to five machines? A B C 25 D 120 E 3,125 51 In an assignment method problem, if it takes Abe hours to build a birdhouse and hours for a doghouse, while Betty takes hours for a birdhouse and hours for a doghouse, what is the reduced cost (in hours) of assigning Abe to build the doghouse? A hours B hour C hours D hours E hours 52 The matrix below shows relative costs for various job-machine combinations Which set of pairs constitutes the minimum-cost solution using the Assignment method? A 1-B, 2-C, 3-A B 1-B, 2-A, 3-C C 1-A, 2-C, 3-B D 1-A, 2-B, 3-C E 1-C, 2-A, 3-B 53 Based on the cost information given in the table below, which set of job-machine pairs reflects the minimum-cost solution using the Assignment method? A 1-B, 2-A, 3-C B 1-A, 2-B, 3-C C 1-C, 2-A, 3-B D 1-B, 2-C, 3-A E 1-C, 2-B, 3-A 54 Effective scheduling cannot: A yield cost savings and improved productivity B reduce the need for expansion of facilities C improve customer service D eliminate the need to train employees E improve patient care in medical settings 55 The priority rule where jobs are processed according to the smallest ratio of due date to processing time is: A CR B EEDD C FCFS D S/O E SPT 56 Scheduled due dates are the result of: A promises to customers B MRP processing C managerial decisions D all of the above E our competitor's promises 57 Which of the following is not a measure for judging the effectiveness of a schedule sequence? A average number of jobs at the work center B total number of jobs at the work center C average completion (flow) time D average job tardiness E none of the above 58 The purpose of cyclical scheduling is to: A eliminate weekends and holidays B rotate schedules C add flexible hours D incorporate overtime E observe work patterns 59 Average completion (flow) time for a schedule sequence at a work center is: A the sum of processing time divided by the number of jobs B the sum of jobs' flow times divided by the number of jobs C overall flow time divided by total processing time D total processing time plus total late time divided by number of jobs E the sum of flow time plus total late time divided by number of jobs 60 The scheduling sequencing rule which always results in the lowest average completion (flow) time is the: A first come, first served (FCFS) rule B shortest processing time first (SPT) rule C earliest due date first (EDD) rule D least slack per operation first (S/O) rule E run until slack happens (RUSH) rule 61 Which sequencing rule is designed specifically to minimize job tardiness? A S/O B EDD C FCFS D SPT E LPT 62 A scheduling rule used for sequencing jobs through two work centers is: A critical ratio rule B Johnson's rule C slack per operation rule D shortest processing time rule E Pareto rule 63 For the jobs listed below, which processing sequence would result using Johnson's Rule? A c-a-d-b B b-d-a-c C a-b-c-d D d-c-b-a E c-a-b-d 64 What is the optimum job sequence for the jobs listed below using Johnson's Rule? A e-g-f-d B d-g-f-e C d-f-g-e D e-d-f-g E f-e-d-g 100 Where in the optimum sequence should car E be scheduled? A first B second C third D fourth E fifth With Johnson's Rule, E will be first in the schedule AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #100 Topic Area: Scheduling in Low-Volume Systems 101 Where in the optimum sequence should car A be scheduled? A first B second C third D fourth E fifth With Johnson's Rule, A will be last in the sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #101 Topic Area: Scheduling in Low-Volume Systems 102 What is the optimum sequence (first car to last)? A A; B; C; D; E B E; D; C; B; A C E; B; D; C; A D E; D; B; C; A E E; B; D; A; C This is the Johnson's Rule sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #102 Topic Area: Scheduling in Low-Volume Systems 103 What is the throughput time for the optimal schedule? A 24 hours B 25 hours C 26 hours D 28 hours E 50 hours This is the makespan that results from using Johnson's Rule AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #103 Topic Area: Scheduling in Low-Volume Systems 104 What is the idle time at the paint work center for the optimal schedule? A hour B hours C hours D hours E 10 hours There are four hours of idle time at the paint work center AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #104 Topic Area: Scheduling in Low-Volume Systems Stevenson - Chapter 16 105 What is the result of the row reduction? Feedback: This is the result of the row reduction AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading Stevenson - Chapter 16 #105 Topic Area: Scheduling in Low-Volume Systems 106 What is the result of the row and column reductions? Feedback: This is the result of the row and column reductions AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading Stevenson - Chapter 16 #106 Topic Area: Scheduling in Low-Volume Systems 107 Can an optimum assignment be made after the row and column reductions? No Feedback: The minimum number of lines to cover all zeroes is AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading Stevenson - Chapter 16 #107 Topic Area: Scheduling in Low-Volume Systems 108 What is the result of modifying the row and column reductions table? Feedback: Here is the modified row and column reduction table AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading Stevenson - Chapter 16 #108 Topic Area: Scheduling in Low-Volume Systems 109 Can an optimum assignment be made after the first modification of the row and column reductions table? Yes Feedback: Now the minimum number of lines needed to cover all zeroes is AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading Stevenson - Chapter 16 #109 Topic Area: Scheduling in Low-Volume Systems 110 What is the optimum assignment of jobs to machines? to A; to B; to C Feedback: This is the optimum set of assignments AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading Stevenson - Chapter 16 #110 Topic Area: Scheduling in Low-Volume Systems 111 What are the total costs for the optimum assignment of jobs to machines? $14 Feedback: Given the optimum assignments, this is the total cost AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading Stevenson - Chapter 16 #111 Topic Area: Scheduling in Low-Volume Systems Refer to the following data for jobs waiting to be processed at a single work center (jobs are shown in order of arrival): Stevenson - Chapter 16 112 What is the schedule sequence using the first come, first served (FCFS) priority rule? A-B-C-D-E Feedback: This is the FCFS sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #112 Topic Area: Scheduling in Low-Volume Systems 113 What is the average completion time for the first come, first served (FCFS) priority rule schedule? Average job tardiness? Average number of jobs at the center? 11.6 days; 5.6 days; 2.9 jobs Feedback: These values result from using FCFS AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #113 Topic Area: Scheduling in Low-Volume Systems 114 What is the schedule sequence using the earliest due date (EDD) priority rule? A-B-D-E-C Feedback: This is the EDD sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #114 Topic Area: Scheduling in Low-Volume Systems 115 What is the average completion time for the earliest due date (EDD) priority rule schedule? Average job tardiness? Average number of jobs at the center? 10.2 days; 4.2 days; 2.55 jobs Feedback: These values result from the EDD sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #115 Topic Area: Scheduling in Low-Volume Systems 116 If jobs A, B, and C require two operations each, while jobs D and E require one operation each, what is the schedule sequence using the slack per operation (S/O) priority rule? A-B-D-E-C Feedback: This is the S/O sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #116 Topic Area: Scheduling in Low-Volume Systems 117 What is the average completion time for the slack per operation (S/O) priority rule schedule? Average job tardiness? Average number of jobs at the center? 10.6 days; 4.6 days; 2.65 jobs Feedback: These values result from using the S/O rule AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #117 Topic Area: Scheduling in Low-Volume Systems 118 What is the schedule sequence using the shortest processing time (SPT) priority rule? A-D-E-B-C Feedback: This is the SPT sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #118 Topic Area: Scheduling in Low-Volume Systems 119 What is the average completion time for the shortest processing time (SPT) priority rule? Average job tardiness? Average number of jobs at the center? 10 days; days; 2.5 jobs Feedback: These values result from using SPT AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #119 Topic Area: Scheduling in Low-Volume Systems Given the following data for jobs awaiting processing at a manufacturing cell in which jobs are first processed by machine A, then by Machine B: Stevenson - Chapter 16 120 If these jobs were scheduled in the sequence shown, what would be the throughput time? 20 hours Feedback: The W-X-Y-Z sequence would have a makespan of 20 hours AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #120 Topic Area: Scheduling in Low-Volume Systems 121 If these jobs were scheduled in the sequence shown, what would be the idle time at machine B? hours Feedback: Idle time would be five hours if this sequence is used AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #121 Topic Area: Scheduling in Low-Volume Systems 122 If these jobs were scheduled in the sequence shown, when would idle time occur at machine B? hours at the outset; hour between W and X Feedback: There would be one hour of idle time between jobs W and X AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #122 Topic Area: Scheduling in Low-Volume Systems 123 In developing the sequence which will minimize throughput time, what is the initial job to be placed in the schedule sequence? Y Feedback: Y would be placed first (on the left-hand side) of the sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #123 Topic Area: Scheduling in Low-Volume Systems 124 In developing the sequence that will minimize throughput time, where in the schedule sequence should job W be placed? W should be second Feedback: W would be placed in the sequence after Y and Z had been placed AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #124 Topic Area: Scheduling in Low-Volume Systems 125 In developing the sequence which will minimize throughput time, where should job X be placed? Third Feedback: X would be the last job placed in the sequence, and it would be in the gap between W and Z AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #125 Topic Area: Scheduling in Low-Volume Systems 126 What is the sequence which will minimize throughput time? Y-W-X-Z Feedback: This is the Johnson's Rule sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #126 Topic Area: Scheduling in Low-Volume Systems 127 What is the throughput time for the optimum schedule? 19 hours Feedback: This is the makespan that results from using Johnson's Rule AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #127 Topic Area: Scheduling in Low-Volume Systems 128 What is the idle time at machine B for the optimum schedule? hours Feedback: B has four hours of idle time in the Johnson's Rule sequence AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #128 Topic Area: Scheduling in Low-Volume Systems 129 When does idle time occur at machine B for the optimum schedule? hour at the outset; hours between Y and W; hour between W and X Feedback: These are the places in the schedule in which machine B is idle AACSB: Analytic Blooms: Apply Difficulty: Medium Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #129 Topic Area: Scheduling in Low-Volume Systems 130 Job X, which has a duration of four days, is due by the close of business on Friday, December 23 Without looking at the work already scheduled on X's required resource, the scheduler schedules X to be begun on the morning of Tuesday, December 20 This is an example of A infinite scheduling B finite scheduling C forward scheduling D backward scheduling E prioritization Backward loading takes a job's due date and subtracts required processing time from that AACSB: Reflective Thinking Blooms: Remember Difficulty: Easy Learning Objective: 16-02 Describe scheduling needs in high-volume and intermediate-volume systems Stevenson - Chapter 16 #130 Topic Area: Scheduling in Low-Volume Systems 131 Job X, which has a duration of four days, is due by the close of business on Friday, December 23 Without looking at the work already at X's required resource, the scheduler schedules X to be begun immediately and assumes that X will be done four days from now This is an example of _ A infinite scheduling B finite scheduling C forward scheduling D backward scheduling E prioritization Forward loading schedules a job ahead from a point in time and assumes its completion date based on that AACSB: Reflective Thinking Blooms: Remember Difficulty: Easy Learning Objective: 16-02 Describe scheduling needs in high-volume and intermediate-volume systems Stevenson - Chapter 16 #131 Topic Area: Scheduling in Low-Volume Systems 132 Job X arrived at work center Q at noon At p.m that same day X was begun X left work center Q at 3:15 p.m that same day X's flow time, in minutes, was A 195 B 120 C 75 D 60 E Cannot be determined Flow time is the difference between when a job leaves a work center and when it arrives at that work center AACSB: Analytic Blooms: Apply Difficulty: Easy Learning Objective: 16-05 Give examples of commonly used priority rules Stevenson - Chapter 16 #132 Topic Area: Scheduling in Low-Volume Systems 133 Which of the following is critical to effective yield management? A one-price pricing B forecasting C capacity flexibility D constant demand E trained service personnel Forecast accuracy is critical to ensuring that adequate capacity is held back for last-minute customers who are not price sensitive AACSB: Reflective Thinking Blooms: Remember Difficulty: Medium Learning Objective: 16-06 Summarize some of the unique problems encountered in service systems; and describe some of the approaches used for scheduling service systems Stevenson - Chapter 16 #133 Topic Area: Scheduling Services 134 Which of the following is least likely to be a consideration when scheduling a high-volume system? A equipment failures B material shortages C accidents D worker absences E demand variability High-volume operations are used when demand exhibits little or no variability AACSB: Reflective Thinking Blooms: Remember Difficulty: Medium Learning Objective: 16-02 Describe scheduling needs in high-volume and intermediate-volume systems Stevenson - Chapter 16 #134 Topic Area: Scheduling Operationsch16 Summary Category # of Questi ons AACSB: Analytic 65 AACSB: Reflective Thinking 69 Blooms: Apply 65 Blooms: Remember 68 Blooms: Understand Difficulty: Easy 23 Difficulty: Hard 11 Difficulty: Medium 100 Learning Objective: 16-01 Explain what scheduling involves and the importance of good scheduling 10 Learning Objective: 16-02 Describe scheduling needs in high-volume and intermediate-volume systems 12 Learning Objective: 16-03 Describe scheduling needs in job shops Learning Objective: 16-04 Use and interpret Gantt charts; and use the assignment method for loading 34 Learning Objective: 16-05 Give examples of commonly used priority rules 66 Learning Objective: 16-06 Summarize some of the unique problems encountered in service systems; and describe some of the approa ches used for scheduling service systems Stevenson - Chapter 16 Topic Area: Operations Strategy 144 Topic Area: Scheduling in Low-Volume Systems 106 Topic Area: Scheduling Operations 18 Topic Area: Scheduling Services ... bottleneck and non-bottleneck operations must be accomplished to optimize output True False 13 As long as the bottleneck operations are used effectively idle time in non-bottleneck operations will not... scheduling needs in high-volume and intermediate-volume systems Stevenson - Chapter 16 #3 Topic Area: Scheduling Operations When operations are often bottlenecked, additional planned idle time... shortest processing time first (SPT) priority rule to schedule these jobs, what will be the average completion time? A 7.5 hours B hours C hours D 2.5 hours E hours 93 If he uses the shortest