Hybrid Algorithm for Solving the Quadratic Assignment Problem

The Quadratic Assignment Problem (QAP) is a combinatorial optimization problem; it belongs to the class of NP-hard problems. This problem is applied in various fields such as hospital layout, scheduling parallel production lines and analyzing chemical reactions for organic compounds. In this paper we propose an application of Golden Ball algorithm mixed with Simulated Annealing (GBSA) to solve QAP. This algorithm is based on different concepts of football. The simulated annealing search can be blocked in a local optimum due to the unacceptable movements; our proposed strategy guides the simulated annealing search to escape from the local optima and to explore in an efficient way the search space. To validate the proposed approach, numerous simulations were conducted on 64 instances of QAPLIB to compare GBSA with existing algorithms in the literature of QAP. The obtained numerical results show that the GBSA produces optimal solutions in reasonable time; it has the better computational time. This work demonstrates that our proposed adaptation is effective in solving the quadratic assignment problem

APPLICATION OF GROUP GENETIC ALGORITHM FOR GENERATION OF CELLS TO SOLVE A MACHINE LAYOUT PROBLEM

This paper explains the improvement of a layout arrangement as a result of application of Group Genetic Algorithm (GGA) on an excel platform for generaation of cells, in celluar manufacturing to minimize distance travelled and materials handling between workstations. It is based on a case study of ABC (Pvt) Ltd, a privately owned manufacturing company in Zimbabwe. The main objective of the study is to come up with manufacturing cells of machine part matrix generated from chromosomes using GGA. The researchers use the GGA to come up with a machine part matrix which reduces distances between machines which processes related parts. Excel is used in calculating fitness function values and the analysis of the best chromosome is done using the radar and line plots. From the study the first offspring in the second generation (chrom 4) is chosen as the best chromosome which enables best machine layout with 83% machine-part movement minimization and 62% machine utilization and 73% effectiveness

Facility Planning and Associated Problems: A Survey

In this study, we have classified and reviewed different types of problems which are related to facility planning and layout design for different types of manufacturing processes. The main problems which are related to location of  facilities which also affects the system performance  such as distribution of man, material and machine in a plant or a factory and their optimization technique while using of mathematical models, their solutions and application related to whole problems is presented. For solving this type of problems, intelligent techniques such as expert systems, fuzzy logic and neutral networks have been used. In this paper the recent analysis on facility layout is incorporated and facility layout problem is surveyed. Many intelligent techniques and conventional algorithms for solving FLP are presented. In our discussion different research direction, general remarks and tendencies have been mentioned Keywords—Facility Planning, Material handling Optimization metho

Facility layout design with genetic algorithms and an application

Tesis yerleşiminin en uygun bir şekilde tasarlanması, üretim tesislerinin etkin ve verimli bir şekilde işletilebilmesinde önemli bir role sahiptir. Tesis yerleşim tasarımı problemleri, çeşitli akış ilişkilerinin de değerlendirilmesini gerektiren problemlerdir ve literatürde Karesel Atama Problemleri (KAP) olarak çözümlendirilmesi yoluna sıkça gidilmiştir. KAP için tesis yerleşimi tasarımı NP-Zor sınıfına girmektedir ve bu nedenle, bu çalışmada, bu tarz problemlere çözüm getirmesi açısından başarılı bir metot olan Genetik Algoritmalar (GA)’dan faydalanılmıştır. Visual Studio C++ 6.0 ortamında LO (Layout Optimizer -Yerleşim En İyileyici) isimli bir yazılım geliştirilmiştir. Bu yazılımla elde edilen sonuçlar, KAP kütüphanesinden alınan literatür problemleriyle test edilmiştir ve her problem için bilinen en iyi çözüme %99’dan daha fazla bir oranda yaklaşılmıştır. Metodoloji, yapısal elektrik malzemeleri imalat sektöründe bir tedarikçi firma için uygulanmıştır ve taşıma maliyetlerinde % 41’lik bir iyileşme sağlanabileceği ortaya konulmuştur.Design of the facility layouts have important effects on the operational productivity and efficiency of a facility. Facility layout design problems (FLDP) are the problems that should consider the flow relations between departments and in the literature the use of Quadratic Assignment Problems (QAP) for these kinds of problems is very frequently applied. Since, for QAP, the FLDP is NP-Hard, in this study, Genetic Algorithms (GA) is utilized. The methodology is coded via Visual Studio C++ 6.0 and the program is called LO (Layout Optimizer). The methodology is tested with QAP library test problems and the difference between LO results and the best known results are less than %1 for each problem. The methodology is applied to a supplier in the structural electricity materials manufacturing sector and a %41 decrease in the transportation costs is expected with the redesign of the facility

Penggunaan Metode Algoritma Craft dan Blocplan untuk Perbaikan Tata Letak Fasilitas Lantai Produksi pada Industri Sparepart Sepeda Motor

Performance and productivity of production line system are very influenced by facility layout planning. Facilities composition which is appropriate with flow of materials between departments, certainly would sustain the continuity of the system. PT. X is one of the subsidiaries of PT. Astra Otoparts Tbk. which manufactures motorcycle chains. Composition of the current layout facilities on the 1st Plant has not fully optimized well and indeed has a potential possibility to be developed further in the future. This statement is supported from the result of existing MHPS which gives Rp 1,047,678.49 for total cost of material handling, 463.1 meters for total distance, and 1,617.24 minutes for total time of material movements. Also, the total area of empty spaces that can be utilized by the company in the current layout is only 89.74 m2. As for the purposes of this research are: analyzing the performance of current layout, developing new layout designs to improve the current one, and comparing the current with proposed improvement layouts. The process of designing proposed layouts is done by using improvement-based algorithm (CRAFT) and hybrid/composite algorithm (BLOCPLAN) that both of the algorithms need same inputs, which are: current facility layout and the flow of material. Based from the results of MHPS calculation for both proposed layouts, show that layout from BLOCPLAN algorithm gives maximal reduction to the total cost of material handling so that the amounts will be decreased to Rp 1,022,419.91 (reducing 2.4% from total cost of current layout), 434.62 meters for total distance (reducing 6.2%), and 1,506.23 minutes for total time of material movements (reducing 6.86%). As for the total area of empty spaces, BLOCPLAN layout gives 110.74 m2 (23.4%) to be minimized than the current layout

Un algoritmo greedy para el diseño de distribución de planta con multi productos y rutas de procesamiento en las instalaciones industriales

Esta tesis aborda el problema de distribución en planta, el cual, en líneas generales, pretende asignar o distribuir instalaciones en un sistema de producción. Existen muchos planteamientos diferentes dependiendo de la naturaleza de los talleres de trabajo consideradas de la planta industrial, por ejemplo el tipo de producto que se fabrica, la flexibilidad requerida en las rutas de procesamiento, la forma de las instalaciones, el número de niveles, etcétera. Uno de los planteamientos más abordados ha sido el problema de distribución en planta con instalaciones de áreas iguales, generalizándose como un problema de asignación cuadrática. Para solucionar este tipo de problemas, el presente trabajo desarrolla un algoritmo greedy para la distribución de las instalaciones en la planta con los siguientes tipos de naturaleza: sistema productivo por procesos, con rutas de procesamiento, presencia de equipos para el manejo de materiales en fila múltiple, distribución en un solo nivel y horizonte de planeamiento estático. El método propuesto AlgoDist minimiza el costo total del manejo de materiales considerando la métrica de distancia Manhattan y logra obtener un equilibrio adecuado entre los algoritmos tipo constructor que generan la distribución ocupando paulatinamente las posiciones del dominio de ubicación, y los algoritmos tipo mejoría que promueven la mejor solución a partir de una distribución inicial de planta. El algoritmo heurístico es bastante eficaz para la resolución de problemas de optimización combinatoria de múltiples filas, con uso de tiempo computacional mínimo. Finalmente, el rendimiento del algoritmo ha sido probado en varios casos de estudio y sus resultados fueron comparados con los obtenidos en otros trabajos citados en la bibliografía, mostrando un grado de eficiencia del 96%, pero con un bajo costo computacional.Tesi

Solving the Multi Objective Flexible Job Shop Problem Using Combinational Meta Heuristic Algorithm Based on Genetic Algorithm and Tabu-Search 1

ABSTRACT Flexible Job Shop Scheduling Problem (FJSSP) has an especial place in industry environments; due to this issue and also due to its mathematical characteristics large number of managers and researchers are considered this problem. Flexible Job Shop Scheduling Problem is more complexthan JSSP and classified as Np-Hard problems. So in this paper a combinational optimization Meta heuristic based on Genetic algorithm is proposed for solving this problem and Tabu search method as a local search algorithm is used to increasing the quality of solutions. In current paper the FJSSP is studied in Multi objective mode and during the solving the problem three objective functions are considered as Makespan, Total workload of machines and Maximum workload of machines and all of them should be minimized. This problem is coded by VBA Software and finally the solutions of proposed algorithm are compared with other papers and the efficiency of solution will be examined

Integrated quadratic assignment and continuous facility layout problem

In this paper, an integrated layout model has been considered to incorporate intra and inter-department layout. In the proposed model, the arrangement of facilities within the departments is obtained through the QAP and from the other side the continuous layout problem is implemented to find the position and orientation of rectangular shape departments on the planar area. First, a modified version of QAP with fewer binary variables is presented. Afterward the integrated model is formulated based on the developed QAP. In order to evaluate material handling cost precisely, the actual position of machines within the departments (instead of center of departments) is considered. Moreover, other design factors such as aisle distance, single or multi row intra-department layout and orientation of departments have been considered. The mathematical model is formulated as mixed-integer programming (MIP) to minimize total material handling cost. Also due to the complexity of integrated model a heuristic method has been developed to solve large scale problems in a reasonable computational time. Finally, several illustrative numerical examples are selected from the literature to test the model and evaluate the heuristic

A simple heuristic for linear sequencing of machines in layout design

This paper presents a simple heuristic to determine a common linear machine sequence for multiple products with different operation sequences and a limited number of duplicate machine types available for the job. The heuristic is based on minimisation of the total flow distance travelled by a product on the linear machine sequence. It is assumed that the flows of products are allowed only in the forward direction, either in-sequence or by-pass. It is also assumed that backtrack movements are not allowed. The effectiveness of the proposed heuristic is demonstrated through the solutions of two typical layout design problems taken from the literature. Subsequently, a number of additional problems are solved and their results are compared with the results applying existing methods. The results indicate that the proposed method can be an effective tool in solving layout design problems