D. Klingman, A. Napier, and J. Stutz. Netgen: A program for generating large scale capacitated assignment, transportation, and minimum cost network ow problems. Management Science, 20:814-821, 1974.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....in the gbin directory underneath the GAMS system directory. AWK is included in this set of tools. If you click on the MSDOS button in the GAMS IDE, a correct path is set up so that these utilities can be used without manually changing the path. 21.2. References. The o#cial reference for NETGEN is [4]. The AWK language is described in [1] 22. Importing GNETGEN network problems GNETGEN is a generator for Generalized Network problem instances based on the NETGEN generator described in the previous paragraph. It can be downloaded from http: www.netlib.org lp generators . The sample seed ....

....The relevant code may look like: call gams String[ cmdArray = new String[5] Figure 5. GAMS ORAQUEUE Model Upload Facility cmdArray[0] C: Program Files GAMS 20.5 gams.exe ; cmdArray[1] D: TMP trnsport.gms ; cmdArray[2] WDIR=D: TMP ; cmdArray[3] SCRDIR=D: TMP ; cmdArray[4] = LO=2 ; Process p = Runtime.getRuntime( exec(cmdArray) p.waitFor( 10. SPAWNING GAMS FROM A WEB SERVER 105 Figure 6. GAMS ORAQUEUE Job Table Page 10. Spawning GAMS from a Web Server Running GAMS remotely using a Web based thin client architecture requires that GAMS is executed directly or ....

D. Klingman, A. Napier, and J. Stutz, NETGEN: A program for generating large scale capacitated assignment, transportation, and minimum cost flow networks, Management Science 20 (1974), 814--820.

....further improved include the selection strategy for commodities to reroute and the technique for choosing 4.4 Experimental Results We have tested our algorithm on a variety of problems and compared its performance to the theoretical bounds. We used two different random network generators, NETGriN[37] and RMrGEN[24] RMFGEN generates graphs that have a set of square planes with connections be tween adjacent planes. When we refer to a graph generated by NETGEN, we will indicate the number of planes. When run on random NETGEN and RMrGEN graphs with randomly placed commodities, our algorithm ....

D. Klingman, A. Napier, and J. Stutz. NETGEN: A program for generating large scale capacitated assignment, transportation, and minimum cost flow network problems. Main agemezt Sciezce, 20:814 821, 1974.

....of current applications of the CM 5. For details the interested reader can also refer to the CM 5 technical summary [96] and the CMMD library guide [97] 90 7. 3 The suite of test problems To assess the relative performance of the three splittings we used MNETGEN [4] a derivative of NETGEN [57], to generate three hundred random multicommodity network problems (MC) one hundred with linear objectives and two hundred with quadratic objective functions. The quadratic objective functions have the form K X i=1 ae c [i] T x [i] r fl fl flx [i] Gamma b x [i] fl fl fl 2 2 oe ....

D. Klingman, A Napier, and J. Stutz. NETGEN: a program for generating large scale capacitated assignment, transportation and minimum cost network problems. Management Science, 20(8):814--821, 1974.

....ensuring generality. Another typical pitfall in this context consists of testing codes on data sets representing classes that are not broad enough. This may lead to inaccurate performance prediction. An extreme example is given by the Netgen problem instances for the minimum cost flow problem [20] that were used to select the best code for a multicommodity flow application [23] That code was later proved to behave much slower than several other codes on real life instances by the same authors of [23] In general, it has been observed that some algorithms behave quite differently if ....

D. Klingman, A. Napier, and J. Stutz. Netgen: A program for generating large scale capacitated assignment, transportation, and minimum cost network flow problems. Management Science, 20:814--821, 1974.

....problem are the width and the height (in number of nodes) the total demand, the number of source and demand nodes, and bounds on the costs. Demand and supply nodes are selected randomly as well as the fraction of the demand supply assigned to a node. The random number generator is that of NETGEN [23]. The variable and fixed costs are uniformly generated over the specified interval using the C C random number generator. Complete, K n . The graph is complete. The number of nodes, the bounds on the costs and the total demand are the parameters needed to specify an instance. The source and ....

Klingman D., Napier A., and Stutz J. Netgen: A program for generating large scale capacitated assignment, transportation, and minimum-cost flow network problems. Management Science, 20:814--820, 1974.

....as above, pricing rules such as first eligible arc rule or Dantzig CPLEX rule need about 14 to 75 times more cpu time for the large scale problems of our test set (e.g. the network problems from Tab. 4) 7 Test Data We evaluate our code on different classes of networks: some are obtained from Klingman, Napier, and Stutz [1974] and created with their network generator NETGEN, some have been generated by ourselves with NETGEN, and some are real world data from our application. NETGEN Networks. To make computational studies of network flow implementations comparable, some problem generators were developed to generate ....

....international algorithm implementation challenge: Problem definitions and specifications (DIMACS [1990] presents standard problem definitions including input and output formats. These formats are widely accepted and supported by almost all publicly available problem generators such as NETGEN (Klingman, Napier, and Stutz [1974]) GRIDGEN (Lee and Orlin) GRIDGRAPH (Goldberg) RMFGEN (Goldfarb and Grigoriadis) etc. All these problem generators are available from DIMACS [1993] Our random test set was generated with NETGEN. The random number seed, which is an input parameter of NETGEN, is for all networks 13502460. ....

Klingman, D., Napier, A., and Stutz, J. (1974). NETGEN: A program for generating large scale capacitated assignment, transportation, and minimum cost flow network problems. Management Science, 20(5).

....0g, ffi 1 and go to STEP 2. else ffi ffi 1. If ffi = 4 then ffi 1, AT AT nf ag and go to STEP 2 else go to STEP 3. 19 4 Numerical results The heuristic procedures developed in this paper have been applied to a set of random instances created using the NETGEN generator of Klingman, Napier and Stutz, 1974. Network sizes range from 50 nodes and 250 arcs to 200 nodes and 9950 arcs. The proportion of tariff arcs varies from 5 to 20 . The arc costs vary from 5 to 35, with 20 of the costs set at their maximum value of 35. In some instances, the tariff arcs are scattered throughout the network, while ....

D. Klingman, A. Napier and J. Stutz, "Netgen : a program for generating large scale capacitated assignment, transportation, and minimum cost flow network problems", Management Science 20, 814-821 (1974).

....STEP 2. else ffi ffi 1. If ffi = 4 then ffi 1, AT AT nf ag and go to STEP 2 else go to STEP 3. 5 Numerical results The heuristic procedures developed in this paper have been applied to a set of random instances created using the NETGEN generator of Klingman, Napier and Stutz [11]. Network sizes range from 50 nodes and 250 arcs to 200 nodes and 9975 arcs. The proportion of tariff arcs varies from 5 to 20 . The arc costs vary from 5 to 35, with 20 of the costs set at their maximum value of 35. In some instances, the tariff arcs are scattered throughout the network, while ....

KLINGMAN D., NAPIER A. et STUTZ J., Netgen : a program for generating large scale capacitated assignment, transportation, and minimum cost flow network problems, Management Science 20, pp. 814-821, 1974.

....and cost parameters are set to 10 4 (10000) The values of X and Y are set as follows: ffl GRID SQUARE family, X = Y ; ffl GRID WIDE family, Y = 16 and X increases; ffl GRID LONG family, X = 16 and Y increases. NETGEN is a classical generator developed by Klingman, Napier, and Stutz [27]. We used a version of NETGEN (obtained from DIMACS and fixed by Bland et al. 6] to generate two example families, NETGEN HI and NETGEN LO. The families are identical except for maximum capacity value. 2 The assignments to the 15 parameters of NETGEN are as follows: ffl NETGEN HI: 1 seed ....

D. Klingman, A. Napier, and J. Stutz. Netgen: A Program for Generating Large Scale Capacitated Assignment, Transportation, and Minimum Cost Flow Network Problems. Management Science, 20:814--821, 1974.

....well adapted to the search of optimal routes in an urban network. Nevertheless, based on his computational experience, Bertsekas concludes in [2] that his code is by far the fastest code for random problems of the type generated by NETGEN (a program that randomly generates shortest path problems [5]) and for few destinations (more than one, but much less than the maximum possible) However, the difference of performance observed here can be explained by several reasons. Origin Algorithm 1 Algorithm 2 1 0.16 0.02 5 0.13 0.01 10 0.19 0.02 20 0.04 0.01 50 0.03 0.01 100 0.84 0.01 150 0.10 0.01 ....

A. Napier D. Klingman and J. Stutz. Netgen: A program for generating large-scale capacitated assignment, transportation, and minimum cost flow network problems. Management Science, 20:814--821, 1974.

....Cholesky factor tend to be much more dense than the original coefficient matrix A, even if there is no dense column in A. Forming and factoring the matrix AD 2 A T is thus quite expensive. We generated minimum cost flow network problems using NETGEN, developed by Klingman, Napier, and Stutz [21]. Table 5 gives the parameters we used, except for the number of nodes and arcs. Table 6 summarizes the characteristics of the resulting linear programming problems. To prevent rank deficiency, we let the adaptive algorithm keep the artificial variables, but we let OB1 R discard the artificial ....

D. Klingman, A. Napier, and J. Stutz. NETGEN: A program for generating large scale capacitated assignment, transportation, and minimum cost flow network problems. Management Science, 20(5):814--821, January 1974.

....of random minimum cost network flow problems. Unlike other generators for the same purpose, netrand generates problems with a known optimal solution and offers control over the degree of degeneracy present at optimality. This preliminary version of netrand is intended as a replacement for netgen [20], trying, with some limitations, to provide the user with the same controls over the problem structure and parameters. Currently, netrand can generate uncapacitated mcnf problems, including special sub classes based on bipartite graphs, like the assignment and transportation problems. The user ....

D. Klingman, A. Napier, and J. Stutz, Netgen: A program for generating large scale capacitated assignment, transportation, and minimum cost flow network problems, Management Science, 20 (1974), pp. 814--821.

....codes in a way that makes possible comparisons on the number of iterations required by each method. We have tested the three methods on a set of ten randon test problems. These problems are the first ten of the set of thirty five problems tested in [12] and generated by a revised version of NETGEN [15]. Table 1 reports the characteristics of these ten problems. Problem Number of Number of number variables constraints 1 1308 200 2 1511 200 3 2000 200 4 2200 200 5 2900 200 6 3174 300 7 4519 300 8 5169 300 9 6075 300 10 6320 300 Table 1: Test problems All the computations have been performed in ....

D. Klingman, A. Napier, and J. Stutz. NETGEN: A program for generating largescale capacitated assignment, transportation, and minimum cost flow network problems. Management Science, 20:814--821, 1974.

....Cholesky factor tend to be much more dense than the original coefficient matrix A, even if there is no dense column in A. Forming and factoring the matrix AD 2 A T is thus quite expensive. We generated minimum cost flow network problems using NETGEN, developed by Klingman, Napier, and Stutz [23]. Before comparing the two codes, we illustrate the typical behavior of the adaptive algorithm using three examples. W. Wang, D. P. O Leary Adaptive Iterative Method in IPM 15 LP size Cholesky factor L Problem Rows Columns Nonzeros Density NETLIB: d2q06c 2132 5728 137349 0.060 degen3 1503 ....

D. Klingman, A. Napier, and J. Stutz. NETGEN: A program for generating large scale capacitated assignment, transportation, and minimum cost flow network problems. Management Science, 20(5):814--821, January 1974.

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D. Klingman, A. Napier, and J. Stutz. Netgen: A program for generating large scale capacitated assignment, transportation, and minimum cost network ow problems. Management Science, 20:814-821, 1974.

No context found.

D. Klingman, A. Napier, and J. Stutz. Netgen: A program for generating large scale capacitated assignment, transportation, and minimum cost network flow problems. Management Science, 20:814--821, 1974.

No context found.

D. Klingman, A. Napier, and J. Stutz. Netgen: A program for generating large scale capacitated assignment, transportation, and minimum cost network ow problems. Management Science, 20:814-821, 1974.

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