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D1 exam help with scheduling diagram

Hi, I've already posted this on the official exam post for the Edexcel D1 paper, but no reply yet. I just wanted to know how to directly construct a scheduling diagram, from a given activity network, without drawing the Gantt chart first?
Reply 1
^ For this question specifically
Original post by techfan42
^ For this question specifically


Are there any constraints? Eg time available or workers available?
Reply 3
Original post by SeanFM
Are there any constraints? Eg time available or workers available?


No, you only need to complete the project in the minimum time using as few workers as possible
Original post by techfan42
No, you only need to complete the project in the minimum time using as few workers as possible


I think in the book it says somewhere (in the chapter explaining how to draw scheduling diagrams) that, if given a choice of events, you assign a worker to the event with the lowest latest finishing time, or something like that. Combine that with maybe a planned route in your head and you can definitely do it without a gantt chart, and keeping an eye on the critical path.

I'd probably set one worker doing the critical activities and then the rest doing the others in a particular order. I'd guess that 3 workers was the minimum, not sure you can do it in 2.
Reply 5
Original post by SeanFM
I think in the book it says somewhere (in the chapter explaining how to draw scheduling diagrams) that, if given a choice of events, you assign a worker to the event with the lowest latest finishing time, or something like that. Combine that with maybe a planned route in your head and you can definitely do it without a gantt chart, and keeping an eye on the critical path.

I'd probably set one worker doing the critical activities and then the rest doing the others in a particular order. I'd guess that 3 workers was the minimum, not sure you can do it in 2.


Yeah, I know that, if given a choice, you have to pick the one with the smallest latest time. But I don't know how we formulate the planned route, what order do I follow in placing activites upon the diagram
Original post by techfan42
Yeah, I know that, if given a choice, you have to pick the one with the smallest latest time. But I don't know how we formulate the planned route, what order do I follow in placing activites upon the diagram


The worker with the critical activities (if one worker can afford to do all of the critical activities himself, which is not always the case) goes on the first line, then you get the other guys to do things, making sure that the first worker's activities have all the non-critical requirements satisfied at the right times. (I'm not 100% sure what you're asking, sorry :colondollar:)
Reply 7
Original post by SeanFM
The worker with the critical activities (if one worker can afford to do all of the critical activities himself, which is not always the case) goes on the first line, then you get the other guys to do things, making sure that the first worker's activities have all the non-critical requirements satisfied at the right times. (I'm not 100% sure what you're asking, sorry :colondollar:)


I understand the fact that all critical activities are placed on the first line, with the first respective worker completing them. However, what I don't understand is the thought process which goes in while assigning the other workers activities. For example: would you pick B as the first activity for the second worker. If so, then what would the next one be: G, D, E, L...? That's what I don't get. How are you supposed to assign the remaining activities?
Original post by techfan42
I understand the fact that all critical activities are placed on the first line, with the first respective worker completing them. However, what I don't understand is the thought process which goes in while assigning the other workers activities. For example: would you pick B as the first activity for the second worker. If so, then what would the next one be: G, D, E, L...? That's what I don't get. How are you supposed to assign the remaining activities?


Yes, B first for the second worker is a good start. Then, given the choice, the one with the earliest latest finish time is D. At this point I'd get a third worker to do E, and then give 1 worker all of the activities in the top half of the graph while getting G, L and K done with the other and it should be sorted.

There are multiple perfectly valid answers for this, and even if you get it slightly wrong you will get most of the marks as long as you've done it in time, used the correct amount of workers, drawn it properly (or something like that, I remember the marks being quite generous). Just map things out quickly in your head and do things in a neat order, keeping an eye on what needs to be done for the critical path.

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