Measuring the Quality of Approximate Solutions to Zero-One Programming Problems

1981 ◽  
Vol 6 (3) ◽  
pp. 319-332 ◽  
Author(s):  
Eitan Zemel
2020 ◽  
Vol 54 (2) ◽  
pp. 307-323
Author(s):  
Wen-Chiung Lee ◽  
Jen-Ya Wang

This study introduces a two-machine three-agent scheduling problem. We aim to minimize the total tardiness of jobs from agent 1 subject to that the maximum completion time of jobs from agent 2 cannot exceed a given limit and that two maintenance activities from agent 3 must be conducted within two maintenance windows. Due to the NP-hardness of this problem, a genetic algorithm (named GA+) is proposed to obtain approximate solutions. On the other hand, a branch-and-bound algorithm (named B&B) is developed to generate the optimal solutions. When the problem size is small, we use B&B to verify the solution quality of GA+. When the number of jobs is large, a relative deviation is proposed to show the gap between GA+ and another ordinary genetic algorithm. Experimental results show that the proposed genetic algorithm can generate approximate solutions by consuming reasonable execution time.


1977 ◽  
Vol 33 (6) ◽  
pp. 1503-1508 ◽  
Author(s):  
V. A. Morozov ◽  
N. L. Gol'dman ◽  
M. K. Samarin

2016 ◽  
Vol 55 ◽  
pp. 685-714
Author(s):  
Roderick Sebastiaan De Nijs ◽  
Christian Landsiedel ◽  
Dirk Wollherr ◽  
Martin Buss

This article discusses the quadratization of Markov Logic Networks, which enables efficient approximate MAP computation by means of maximum flows. The procedure relies on a pseudo-Boolean representation of the model, and allows handling models of any order. The employed pseudo-Boolean representation can be used to identify problems that are guaranteed to be solvable in low polynomial-time. Results on common benchmark problems show that the proposed approach finds optimal assignments for most variables in excellent computational time and approximate solutions that match the quality of ILP-based solvers.


Author(s):  
I. V. Kozin ◽  
S. E. Batovskiy

It is known that a large number of applied optimization problems can’t be exactly solved nowadays, because their computational complexity is related to the NP-hard class. In many cases metaheuristics of various types are used to search for approximate solutions, but the choice of the concrete metaheuristic has open question of the quality of the chosen method. There are several possible solutions to this problem, one of which is the verification of metaheuristic algorithms using examples from known test libraries with known records. Another approach to solving the problem of evaluating the quality of algorithms is to compare the "new" algorithm with other algorithms, the work of which has already been investigated. The construction a generator of random problems with a known optimal solution can solve the problem of obtaining "average" estimates of the accuracy for used algorithm in comparison with other methods. The article considers the construction of generators of random non-waste maps of rec-tangular cutting with restrictions on the rectangles of limited sizes. The existence of sets of such cards forms the basis of test problems for checking the quality of approximate algorithms for searching for optimal solution. Rectangular cutting, which is considered in the article, is also the basis for building cuts using more complex shapes. As the simplest method of generating random rectangular non-waste maps, considered a method that uses guillotine cutting. Also, a more complex algorithm for generating a random rectangular cut is given, whose job is to generate a random dot grid and remove some random points from this grid. Much attention is paid to the implementation of the above methods, since the main purpose of the article is to simplify using of generators in practice. All the above algorithms are already used in the software system for testing evolution-aryfragmentary algorithms for various classes of optimization problems on the graphs


2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Tadashi Kawanago

We establish a general existence result for Galerkin's approximate solutions of abstract semilinear equations and conduct an error analysis. Our results may be regarded as some extension of a precedent work (Schultz 1969). The derivation of our results is, however, different from the discussion in his paper and is essentially based on the convergence theorem of Newton’s method and some techniques for deriving it. Some of our results may be applicable for investigating the quality of numerical verification methods for solutions of ordinary and partial differential equations.


Quantum ◽  
2021 ◽  
Vol 5 ◽  
pp. 454
Author(s):  
Benjamin Tan ◽  
Marc-Antoine Lemonde ◽  
Supanut Thanasilp ◽  
Jirawat Tangpanitanon ◽  
Dimitris G. Angelakis

We propose and analyze a set of variational quantum algorithms for solving quadratic unconstrained binary optimization problems where a problem consisting of nc classical variables can be implemented on O(log⁡nc) number of qubits. The underlying encoding scheme allows for a systematic increase in correlations among the classical variables captured by a variational quantum state by progressively increasing the number of qubits involved. We first examine the simplest limit where all correlations are neglected, i.e. when the quantum state can only describe statistically independent classical variables. We apply this minimal encoding to find approximate solutions of a general problem instance comprised of 64 classical variables using 7 qubits. Next, we show how two-body correlations between the classical variables can be incorporated in the variational quantum state and how it can improve the quality of the approximate solutions. We give an example by solving a 42-variable Max-Cut problem using only 8 qubits where we exploit the specific topology of the problem. We analyze whether these cases can be optimized efficiently given the limited resources available in state-of-the-art quantum platforms. Lastly, we present the general framework for extending the expressibility of the probability distribution to any multi-body correlations.


Author(s):  
Sivakumar Rathinam ◽  
Pramod Khargonekar

The problem of finding the shortest path for a vehicle visiting a given sequence of target points subject to the motion constraints of the vehicle is an important problem that arises in several monitoring and surveillance applications involving unmanned aerial vehicles. There is currently no algorithm that can find an optimal solution to this problem. Therefore, heuristics that can find approximate solutions with guarantees on the quality of the solutions are useful. The best approximation algorithm currently available for the case when the distance between any two adjacent target points in the sequence is at least equal to twice the minimum radius of the vehicle has a guarantee of 3.04. This article provides a new approximation algorithm which improves this guarantee to 1+π3≈2.04. The developed algorithm is also implemented for hundreds of typical instances involving at most 30 points to corroborate the performance of the proposed approach.


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