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ASSIGNMENT #6 CIVE 645 1. There may be several routes for conveying water from some upstream node 1 to some particular node N downstream through an existing water distribution system: e.g., (a) In the above network, a given flow Q is transferred through the network to a demand node N. The goal is to route the flows in such a way that total channel loss is minimized, where channel loss coefficients clij per unit length are given for each link or arc of length Lij. Ignore the maximum capacities of the links for this problem and also temporarily ignore the iterative solution process used by MODSIM to calculate channel losses. Specify how the arc paramaters [lij, uij, cij] for any link (i,j) in this network should be defined, as well as the demand node parameters (i.e., priority and demand), that will result in minimization of total channel loss in the MODSIM solution. (b) Instead of Q being specified in the above network, suppose that now the objective is to find the maximum flow that can be delivered to demand node N, assuming that upper bounds uij are now specified on the flow in each link or arc (i,j) and channel losses are ignored. Specify the arc parameters and demand node parameters that would be required to solve this problem with MODSIM [Hint: you may need to add a supply node such as a dummy reservoir].. (c) How would you define the arc parameters and demand node parameters in order to find the shortest path through this network, assuming each link is of length Lij? We are not trying to route flows in this network, but simply identify the shortest connected path through the network. Can this be done in MODSIM? Explain. [Hint: remember that MODSIM preserves integer solutions if all arc parameters are integers.] 1 2 3 j k l m NN Q
2 2. One of the disadvantages of MODSIM is that networks are solved sequentially over each time period, rather than obtaining a fully dynamic optimal solution. Suppose we wanted MODSIM to solve a fully dynamic problem over 2…