In Universal Mobile Telecommunications Systems radio access, information packets of different services and users are sent across the air interface organized into radio frames. A radio frame is divided into a fixed num...
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In Universal Mobile Telecommunications Systems radio access, information packets of different services and users are sent across the air interface organized into radio frames. A radio frame is divided into a fixed number of time slots, different packets can share the same time slot and exactly one slot must be assigned to each packet. The packets of different services have divisible sizes and the slot capacity is limited. Quality of Service requirements set time intervals within which each packet must be scheduled. In this work, we address the problem of scheduling packets related to two different services to the time slots of a radio frame. The problem is a variant of the High-Multiplicity Multiprocessor Scheduling Problem in which there are two classes of jobs with divisible sizes, and the jobs must satisfy assignment restrictions. Two polynomial-time scheduling algorithms, maximizing the number of scheduled packets, and the weighted throughput, are provided.
This paper deals with the single machine scheduling problem with multiple financial resource constraints. It is shown that the problem can be reduced to the two machine flow shop scheduling problem if the financial re...
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This paper deals with the single machine scheduling problem with multiple financial resource constraints. It is shown that the problem can be reduced to the two machine flow shop scheduling problem if the financial resources arrive uniformly over time, and it is also shown that the LPT (Largest Processing Time) rule generates an optimal solution to the problem if the financial resources are consumed uniformly by all the jobs. Hence there exist polynomial algorithms for these two special cases of the problem. (C) 1997 Elsevier Science B.V.
We consider the problem of obtaining integer solutions to a minmax linear programming problem. Although this general problem is NP-complete, it is shown that a restricted version of this problem can be solved in polyn...
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We consider the problem of obtaining integer solutions to a minmax linear programming problem. Although this general problem is NP-complete, it is shown that a restricted version of this problem can be solved in polynomial time. For this restricted class of problems two polynomial time algorithms are suggested, one of which is strongly polynomial whenever its continuous analogue and an associated linear programming problem can be solved by a strongly polynomial algorithm. Our algorithms can also be used to obtain integer solutions for the minmax transportation problem with an inequality budget constraint. The equality constrained version of this problem is shown to be NP-complete. We also provide some new insights into the solution procedures for the continuous minmax linear programming problem.
A number of results in hamiltonian graph theory are of the form "P-1 implies P-2", where P-1 is a property of graphs that is NP-hard and P-2 is a cycle structure property of graphs that is also NP-hard. An e...
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A number of results in hamiltonian graph theory are of the form "P-1 implies P-2", where P-1 is a property of graphs that is NP-hard and P-2 is a cycle structure property of graphs that is also NP-hard. An example of such a theorem is the well-known Chvatal-Erdos Theorem, which states that every graph G with alpha less than or equal to kappa is hantiltonian. Here kappa is the vertex connectivity of G and alpha is the cardinality of a largest set of independent vertices of G. In another paper Chvatal points out that the proof of this result is in fact a polynomial time construction that either produces a Hamilton cycle or a set of more than kappa independent vertices. In this note we point out that other theorems in hamiltonian graph theory have a similar character. In particular, we present a constructive proof of a well-known theorem of Jung (Ann. Discrete Math. 3 (1978) 129) for graphs on 16 or more vertices. (C) 2002 Elsevier Science B.V. All rights reserved.
This paper describes several algorithms for solution of linear programs. The algorithms are polynomial when the problem data satisfy certain conditions.
This paper describes several algorithms for solution of linear programs. The algorithms are polynomial when the problem data satisfy certain conditions.
In this paper the problem of optimally guillotine cutting a rectangle (A, B) into small rectangles of two kinds is considered. Rectangles of the first kind (c,a(i)), i is an element of I have the same width, and their...
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In this paper the problem of optimally guillotine cutting a rectangle (A, B) into small rectangles of two kinds is considered. Rectangles of the first kind (c,a(i)), i is an element of I have the same width, and their heights can be various. Rectangles of the second kind (b(j),d), j is an element of J have the same height, and their widths can be various. The number of occurrences of each small rectangle in a cutting pattern is not restricted. Similar problems often appear in the furniture industry. This cutting problem is reduced to the shortest path problem in a special rectangular grid, for which a linear time algorithm is suggested. This approach generalizes the approach of [E. Girlich, A.G. Tarnowski, On polynomial solvability of two multiprocessor scheduling problems, Mathematical Methods of Operations Research 50 (1999) 27-51;A.G. Tarnowski, Advanced polynomial time algorithm for guillotine generalized pallet loading problem, in: The International Scientific Collection: Decision Making Under Conditions of Uncertainty (Cutting-Packing Problems), Ufa State Aviation Technical University, 1997, pp. 93-124] and allows us to construct polynomial algorithms for the guillotine cutting problem considered with a fixed number of small rectangles of two kinds. (c) 2007 Elsevier B.V. All rights reserved.
polynomial algorithms for solving the quadratic assignment problem on special types of networks are proposed. The structure of the links between the objects to be located is represented by a graph.
polynomial algorithms for solving the quadratic assignment problem on special types of networks are proposed. The structure of the links between the objects to be located is represented by a graph.
To estimate test reliability and to create parallel tests, test items frequently are matched. Items can be matched by splitting tests into parallel test halves, by creating T splits, or by matching a desired test form...
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To estimate test reliability and to create parallel tests, test items frequently are matched. Items can be matched by splitting tests into parallel test halves, by creating T splits, or by matching a desired test form. Problems often occur. algorithms are presented to solve these problems. The algorithms are based on optimization theory in networks (graphs) and have polynomial complexity. Computational results from solving sample problems with several hundred decision variables are reported.
We consider three graph partitioning problems, both from the vertices and the edges point of view. These problems are dominating set, list-q-coloring with costs (fixed number of colors q) and coloring with non-fixed n...
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The paper considers the Common Due-Window (CDW) problem where a single machine processes a certain number of jobs against a common due-window. Each job possesses different processing times but different and asymmetric...
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ISBN:
(纸本)9781479945009
The paper considers the Common Due-Window (CDW) problem where a single machine processes a certain number of jobs against a common due-window. Each job possesses different processing times but different and asymmetric earliness and tardiness penalties. The objective of the problem is to find the processing sequence of jobs, their completion times and the position of the given due-window to minimize the total penalty incurred due to tardiness and earliness of the jobs. This work presents exact polynomial algorithms for optimizing a given job sequence for a single machine with the run-time complexity of O(n(2)), where n is the number of jobs. We also provide an O (n) algorithm for optimizing the CDW with unit processing times. The algorithms take a sequence consisting of all the jobs (J(i,i) = 1, 2, ..., n) as input and return the optimal completion times, which offers the minimum possible total penalty for the sequence. Furthermore, we implement our polynomial algorithms in conjunction with Simulated Annealing (SA) to obtain the best processing sequence. We compare our results with that of Biskup and Feldmann [1] for different due-window lengths.
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