1 华中科技大学本科生课程考试试卷(A A 卷) 课程名称：企业生产与物流管理 课程类别 公共课 专业课 考试形式 开卷 闭卷 所在院系： 专业及班级： 考试日期： 2013.7.4 学 号： 姓 名： 任课教师： 祁超 题号 一 二 三 四 五 六 总分 分数 1. Given the following product structure, master production schedule, and related information. Complete a material requirements planning for item D (i.e. identify the planned order release for item D). Assume the adopted lot sizing rule is lot-for-lot. (15 points) Period 45678 9 10 11 12 Gross requirements for item X 50 20 100 Item On hand Lead Time Item On hand Lead Time X 50 1 A 5 1 B1 20 2 C 0 1 B2 20 2 D 10 2 X B1(1)B2(2) A(1) D(1)C(2)D(2) 2 Answer: 4 5 6 7 8 9 10 11 12 4 5 6 7 8 9 10 11 12 4 5 6 7 8 9 10 11 12 4 5 6 7 8 9 10 11 12 3 2. The following jobs are waiting to be processed at Jeremy LaMontagnes machine center. Today is 250. Job Release Date Processing Time (days)Due Date 1 215 30 260 2 220 20 290 3 225 40 300 4 240 50 320 5 250 20 340 Sequence the five jobs using First-Come-First-Served (FCFS), Shortest Processing Time (SPT), Minimal Slack (MS), and Critical Ratio (CR), respectively. For each obtained sequence, please compute the completion time (Cj), flow time (Fj), and tardiness (Tj) for each job. In addition, please compare the average flow time, average tardiness, and maximum tardiness associated with these dispatching rules. (15 points) 4 5 3. Apply shifting bottleneck heuristic to the following job shop scheduling instance with the makespan objective. (20 points) Jobs Machine Sequence Processing Times 1 1, 2, 3, 4 p11=9;p21=8;p31= 4;p41= 4 2 1, 2, 4, 3 p12=5;p22=6;p42=3;p32=6 3 3, 1, 2, 4 p33=10;p13= 4;p23=9;p43=2 6 7 4. Six jobs are to be processed through a two-step operation. The first operation involves sanding, and the second involves painting. Processing times are as follows: Job Operation 1 (hours) Operation 2 (hours) A 10 5 B 7 4 C 5 7 D 3 8 E 2 6 F 4 3 (1) Determine a sequence to minimize the maximum completion time (i.e. makespan) for these six jobs. (5 points) (2) Illustrate the obtained schedule graphically using Gantt Chart, and compute the makespan. (5 points) 8 9 5. Development of a new deluxe version of a particular software product is being considered by Ravi Beharas software house. The activities necessary for the completion of the project are listed in the following table. Activity Normal Time (weeks) Expedited Time (weeks) Normal Cost Expedited Cost Immediate Predecessor(s) A 4 3 $2000$2600- B 2 1 22002800- C 3 3 500500- D 8 4 23002600A E 6 3 9001200B F 3 2 30004200C G 4 2 14002000D, E （1） Draw the Job-On-Node network diagram for the project. (4 points) （2） Use Critical Path Method based on normal times. Compute the earliest starting time (ES), earliest finishing time (EF), latest starting time (LS), and latest finishing time (LF) for each activity. Identify the critical path, the critical activities, makespan, and the total cost to complete the project on normal times. (6 points) （3） If you wish to reduce the makespan by 1 week, which activity should be expedited, and how much will this increase the total cost? (4 points) （4） Identify the shortest makespan following time/cost tradeoff heuristic. How much will cost increase compared with the cost in (2)? (6 points) 10 11 6. Michael Carrigg, Inc., is a disk manufacturer in need of an aggregate plan for July through December. The company has gathered the following data. Assume the working hour per day is 24 hours, in which 8 hours are regular time, and the hours above 8 hours are overtime. Costs Holding cost $8/disk/month Subcontracting $80/disk Regular-time labor $12/hour/worker Overtime labor $18/hour for hours above 8 hours/worker/day Hiring cost $40/worker Firing cost $80/worker Demand July 400 Aug. 500 Sept. 550 Oct. 700 Nov. 800 Dec. 700 Other data Current workforce (June) 8 people Labor-hours/disk 4 hours Workingdays/month 20 days Beginning inventory (at the begging of July) 150 disks Ending inventory (at the end of Dec.) 0 disks （1）Develop the aggregate plan by varying the workforce level for each month so that production meets demand, and compute the total cost of the plan. The company has 8 workers on board in June. (10 points) （2）Develop the aggregate plan by varying overtime only and using a constant workforce of 8 workers. Compute the total cost of the plan. (10 points) 12