(a) The following tasks are to be assigned to work stations with the intention of minimising...

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(a) The following tasks are to be assigned to work stations with the intention of minimising idle time. Precedence relationships are shown. Management has designated an output of 500 units per day. Assume 420 minutes are available each day. Task A Duration (seconds) Immediate predecessor 45 BEM2007 B 11 A C 9 B D 50 E 15 D F G H T J K 222289 12 C 12 C 12 E 12 E F,G,H,I J 2 Turn over Question 2 (continued) 1. Construct a precedence diagram for the tasks. 2. Calculate the cycle time. 3. Using the cycle time calculated in 2, balance the line. There are two heuristic (assignment) rules. The primary rule is to prioritise the selection of tasks according to the "largest number of following tasks": count the number of following tasks and choose the task with the largest number of following tasks. Where there is a tie, apply the secondary rule "choose the longest operating time". If there is again a tie (with equal operating times), then select a task arbitrarily. 4. Indicate dearly which tasks are to be grouped together in the appropriate number of work stations. 5. Comment on the efficiency of the line and suggest how efficiency could be improved. 5 marks 2 marks 9 marks 2 marks 2 marks 20 marks (a) The following tasks are to be assigned to work stations with the intention of minimising idle time. Precedence relationships are shown. Management has designated an output of 500 units per day. Assume 420 minutes are available each day. Task A Duration (seconds) Immediate predecessor 45 BEM2007 B 11 A C 9 B D 50 E 15 D F G H T J K 222289 12 C 12 C 12 E 12 E F,G,H,I J 2 Turn over Question 2 (continued) 1. Construct a precedence diagram for the tasks. 2. Calculate the cycle time. 3. Using the cycle time calculated in 2, balance the line. There are two heuristic (assignment) rules. The primary rule is to prioritise the selection of tasks according to the "largest number of following tasks": count the number of following tasks and choose the task with the largest number of following tasks. Where there is a tie, apply the secondary rule "choose the longest operating time". If there is again a tie (with equal operating times), then select a task arbitrarily. 4. Indicate dearly which tasks are to be grouped together in the appropriate number of work stations. 5. Comment on the efficiency of the line and suggest how efficiency could be improved. 5 marks 2 marks 9 marks 2 marks 2 marks 20 marks