Design of Flotation Circuits Using Tabu-Search Algorithms: Multispecies, Equipment Design, and Profitability Parameters

The design of a flotation circuit based on optimization techniques requires a superstructure for representing a set of alternatives, a mathematical model for modeling the alternatives, and an optimization technique for solving the problem. The optimization techniques are classified into exact and approximate methods. The first has been widely used. However, the probability of finding an optimal solution decreases when the problem size increases. Genetic algorithms have been the approximate method used for designing flotation circuits when the studied problems were small. The Tabu-search algorithm (TSA) is an approximate method used for solving combinatorial optimization problems. This algorithm is an adaptive procedure that has the ability to employ many other methods. The TSA uses short-term memory to prevent the algorithm from being trapped in cycles. The TSA has many practical advantages but has not been used for designing flotation circuits. We propose using the TSA for solving the flotation circuit design problem. The TSA implemented in this work applies diversification and intensification strategies: diversification is used for exploring new regions, and intensification for exploring regions close to a good solution. Four cases were analyzed to demonstrate the applicability of the algorithm: different objective function, different mathematical models, and a benchmarking between TSA and Baron solver. The results indicate that the developed algorithm presents the ability to converge to a solution optimal or near optimal for a complex combination of requirements and constraints, whereas other methods do not. TSA and the Baron solver provide similar designs, but TSA is faster. We conclude that the developed TSA could be useful in the design of full-scale concentration circuits.

Download Full-text

A Tabu-Gradient Search-Based Optimization Technique for Synthesis of Mechanisms

Volume 2: 28th Biennial Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2004-57420 ◽

2004 ◽

Author(s):

Ahmad Smaili ◽

Naji Atallah

Keyword(s):

Tabu Search ◽

Global Minimum ◽

Short Term Memory ◽

Search Algorithm ◽

Random Search ◽

Optimization Technique ◽

Optimization Methods ◽

Gradient Search ◽

Optimum Synthesis ◽

Timing Task

Mechanism synthesis requires the use of optimization methods to obtain approximate solution whenever the desired number of positions the mechanism is required to traverse exceeds a few (five in a 4R linkage). Deterministic gradient-based methods are usually impractical when used alone because they move in the direction of local minima. Random search methods on the other hand have a better chance of converging to a global minimum. This paper presents a tabu-gradient search based method for optimum synthesis of planar mechanisms. Using recency-based short-term memory strategy, tabu-search is initially used to find a solution near global minimum, followed by a gradient search to move the solution ever closer to the global minimum. A brief review of tabu search method is presented. Then, tabu-gradient search algorithm is applied to synthesize a four-bar mechanism for a 10-point path generation with prescribed timing task. As expected, Tabu-gradient base search resulted in a better solution with less number of iterations and shorter run-time.

Download Full-text

TABU SEARCH ALGORITHM FOR OPTIMIZING PILE FOUNDATION LAYOUT ON FOOTING OF RESIDENTIAL HOUSE

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2015.102 ◽

2015 ◽

Vol 2 (1) ◽

Author(s):

Takahiro Hara ◽

Buntara S. Gan

Keyword(s):

Tabu Search ◽

Pile Foundation ◽

Optimization Problems ◽

Search Algorithm ◽

Tabu Search Algorithm ◽

Design Practice ◽

Local Optima ◽

Combinatorial Optimization Problems ◽

Recent Advancement ◽

Residential House

In practice, positioning pile foundation on footing layout of a residential house is often based on empirical judgment and long working experiences of a designer. After the pile requirements calculated, some conditions like number of piles, spacing placement of all piles on the footing, and locations such as under columns, corner, or intersection have to be determined. Besides, the coincidence of shear and gravity centers is also another essential design consideration, which is often ignored in design practice. The present study is aimed at eliminating the horizontal torsion effects during the earthquakes occurrences by reducing the eccentricity distance between the centers of gravity and shear. The scope of present study excludes any foundation or structural related design and analysis. Recent advancement of computing capabilities of computers has made the structural analysis become a convenient tool at hand for designers. In this study, the Tabu Search algorithm was adopted as an optimization tool for pile placing on the footing of residential houses. Tabu Search algorithm was known as an efficient method for solving combinatorial optimization problems where it can find some quality solutions in relatively short running time without getting stuck in local optima. An example of footing layout design was demonstrated to show the effectiveness of the present study as a decision-making tool in design practice.

Download Full-text

A TABU SEARCH ALGORITHM FOR POST-PROCESSING MULTIPLE SEQUENCE ALIGNMENT

Journal of Bioinformatics and Computational Biology ◽

10.1142/s0219720005000928 ◽

2005 ◽

Vol 03 (01) ◽

pp. 145-156 ◽

Cited By ~ 5

Author(s):

TARIQ RIAZ ◽

WANG YI ◽

KUO-BIN LI

Keyword(s):

Tabu Search ◽

Sequence Alignment ◽

Multiple Sequence Alignment ◽

Optimization Problems ◽

Search Algorithm ◽

Solution Space ◽

Adaptive Memory ◽

Multiple Sequence ◽

Local Optima ◽

Combinatorial Optimization Problems

Tabu search is a meta-heuristic approach that is proven to be useful in solving combinatorial optimization problems. We implement the adaptive memory features of tabu search to refine a multiple sequence alignment. Adaptive memory helps the search process to avoid local optima and explores the solution space economically and effectively without getting trapped into cycles. The algorithm is further enhanced by introducing extended tabu search features such as intensification and diversification. The neighborhoods of a solution are generated stochastically and a consistency-based objective function is employed to measure its quality. The algorithm is tested with the datasets from BAliBASE benchmarking database. We have observed through experiments that tabu search is able to improve the quality of multiple alignments generated by other software such as ClustalW and T-Coffee. The source code of our algorithm is available at .

Download Full-text

APPLYING TABU SEARCH TO THE TWO-DIMENSIONAL ISING SPIN GLASS

International Journal of Modern Physics C ◽

10.1142/s0129183195000034 ◽

1995 ◽

Vol 06 (01) ◽

pp. 11-23 ◽

Cited By ~ 2

Author(s):

MANUEL LAGUNA ◽

PABLO LAGUNA

Keyword(s):

Tabu Search ◽

Spin Glasses ◽

Statistical Physics ◽

Optimization Problems ◽

Approximate Solutions ◽

Optimization Techniques ◽

Two Dimensional ◽

Optimal Solutions ◽

Spin Lattice ◽

Combinatorial Optimization Problems

A variety of problems in statistical physics, such as Ising-like systems, can be modeled as integer programs. Physicists have relied mostly on Monte Carlo methods to find approximate solutions to these computationally difficult problems. In some cases, optimal solutions to relatively small problems have been found using standard optimization techniques, e.g., cutting plane and branch-and-bound algorithms. Motivated by the success of tabu search (TS) in finding optimal or near-optimal solutions to combinatorial optimization problems in a number of different settings, we study the application of this methodology to Ising-like systems. Particularly, we develop a TS method to find ground states of two-dimensional spin glasses. Our method performs a search at different levels of resolution in the spin lattice, and it is designed to obtain optimal or near-optimal solutions to problem instances with several different characteristics. Results are reported for computational experiments with up to 64×64 lattices.

Download Full-text

The Ply Stacking Optimization for Composite Laminated Structure: Application of Tabu Search Algorithm

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.366.514 ◽

2011 ◽

Vol 366 ◽

pp. 514-517

Author(s):

Jing Zhang

Keyword(s):

Tabu Search ◽

Optimization Problems ◽

Search Algorithm ◽

Orientation Angle ◽

Composite Fiber ◽

Neighborhood Search ◽

Optimized Design ◽

Tabu Search Algorithm ◽

Laminated Structure ◽

Combinatorial Optimization Problems

In this paper, tabu search algorithm, the laminated overlay has been optimized. The total thickness of the laminated structure under certain circumstances, to composite laminates maximum system reliability indices as the objective function, the composite fiber orientation angle and relative thickness of the optimized design. It is through the local neighborhood search mechanism and the corresponding tabus to avoid circuitous search criteria and standards to cut through the broken tabu excellent release from the state, thereby ensuring a variety of effective exploration in order to ultimately achieve global optimization. This article is laminated overlay design provide a new and efficient framework, the framework of the algorithm relative to the previously used method has obvious advantages: After a limited number of cycles that can converge to satisfactory results, the optimization process shows good robustness of the algorithm, and the method to solve the structural optimization of composite materials and other combinatorial optimization problems provide a new way of thinking. This paper describes the basic idea of tabu search algorithm, composition, processes, principles, and so on.

Download Full-text

A Tabu Search for Multi-Objective Single Row Facility Layout Problem

Journal of Advanced Manufacturing Systems ◽

10.1142/s0219686714500024 ◽

2014 ◽

Vol 13 (01) ◽

pp. 17-40 ◽

Cited By ~ 12

Author(s):

N. Lenin ◽

M. Siva Kumar ◽

D. Ravindran ◽

M. N. Islam

Keyword(s):

Tabu Search ◽

Optimization Problems ◽

Search Algorithm ◽

Facility Layout ◽

Support Tool ◽

Single Row ◽

Multi Objective ◽

Combinatorial Optimization Problems ◽

Machine Sequence ◽

Linear Machine

This paper addresses the problem of multi-objective facility layout planning. The aim is to solve the single row facility layout problems (SRFLP) and find the linear machine sequence which minimizes the following: The total investment cost of machines; the total material handling cost; the total number of machines in the final sequence; and the total flow distance of the products in units. The tabu search algorithm (TSA) which has now become a very useful tool in solving a variety of combinatorial optimization problems is made use of here. TSA is developed to determine the product sequence based on which a common linear machine sequence is found out for multi-products with different machine sequences. We assume that, limited number of duplicate machine types available for job. The results are compared with other approaches and it shows the effectiveness of the TSA approach as a practical decision support tool to solve problems in SRFLP.

Download Full-text

Linking Search Space Structure, Run-Time Dynamics, and Problem Difficulty: A Step Toward Demystifying Tabu Search

Journal of Artificial Intelligence Research ◽

10.1613/jair.1576 ◽

2005 ◽

Vol 24 ◽

pp. 221-261 ◽

Cited By ~ 8

Author(s):

J. P. Watson ◽

L. D. Whitley ◽

A. E. Howe

Keyword(s):

Random Walk ◽

Tabu Search ◽

Optimization Problems ◽

Search Algorithm ◽

Search Space ◽

Tabu Search Algorithm ◽

Problem Difficulty ◽

Time Dynamics ◽

Combinatorial Optimization Problems ◽

Run Time

Tabu search is one of the most effective heuristics for locating high-quality solutions to a diverse array of NP-hard combinatorial optimization problems. Despite the widespread success of tabu search, researchers have a poor understanding of many key theoretical aspects of this algorithm, including models of the high-level run-time dynamics and identification of those search space features that influence problem difficulty. We consider these questions in the context of the job-shop scheduling problem (JSP), a domain where tabu search algorithms have been shown to be remarkably effective. Previously, we demonstrated that the mean distance between random local optima and the nearest optimal solution is highly correlated with problem difficulty for a well-known tabu search algorithm for the JSP introduced by Taillard. In this paper, we discuss various shortcomings of this measure and develop a new model of problem difficulty that corrects these deficiencies. We show that Taillard's algorithm can be modeled with high fidelity as a simple variant of a straightforward random walk. The random walk model accounts for nearly all of the variability in the cost required to locate both optimal and sub-optimal solutions to random JSPs, and provides an explanation for differences in the difficulty of random versus structured JSPs. Finally, we discuss and empirically substantiate two novel predictions regarding tabu search algorithm behavior. First, the method for constructing the initial solution is highly unlikely to impact the performance of tabu search. Second, tabu tenure should be selected to be as small as possible while simultaneously avoiding search stagnation; values larger than necessary lead to significant degradations in performance.

Download Full-text

Solving examination timetabling problem within a hyper-heuristic framework

Bulletin of Electrical Engineering and Informatics ◽

10.11591/eei.v10i3.2996 ◽

2021 ◽

Vol 10 (3) ◽

Author(s):

Shinta Dewi ◽

Raras Tyasnurita ◽

Febriyora Surya Pratiwi

Keyword(s):

Tabu Search ◽

Optimization Problems ◽

Search Algorithm ◽

Exact Algorithm ◽

Time Algorithm ◽

Hill Climbing ◽

Exam Timetabling ◽

University Of Toronto ◽

Combinatorial Optimization Problems ◽

Hard Constraints

Scheduling exams in colleges are a complicated job that is difficult to solve conventionally. Exam timetabling is one of the combinatorial optimization problems where there is no exact algorithm that can answer the problem with the optimum solution and minimum time possible. This study investigated the University of Toronto benchmark dataset, which provides 13 real instances regarding the scheduling of course exams from various institutions. The hard constraints for not violate the number of time slots must be fulfilled while paying attention to fitness and running time. Algorithm of largest degree, hill climbing, and tabu search within a hyper-heuristic framework is investigated with regards to each performance. This study shows that the Tabu search algorithm produces much lower penalty value for all datasets by reducing 18-58% from the initial solution.

Download Full-text

Optimal Design of Mechanisms Using Simulated Annealing: Theory and Applications

14th Design Automation Conference ◽

10.1115/detc1988-0030 ◽

1988 ◽

Author(s):

P. Jain ◽

A. M. Agogino

Keyword(s):

Simulated Annealing ◽

Combinatorial Optimization ◽

Computer Aided Design ◽

Optimization Problems ◽

Mechanical Design ◽

Optimization Technique ◽

Global Optimum ◽

Optimization Techniques ◽

Kinematic Synthesis ◽

Combinatorial Optimization Problems

Abstract A new approach to optimization in kinematic synthesis of mechanisms is presented which is based on simulated annealing, a probabilistic combinatorial optimization technique. The advantage of this technique is that it converges to the global optimum asymptotically. Simulated annealing has been successfully applied to solve several combinatorial optimization problems in the fields of computer-aided design of VLSI chips, image processing and graph theory. However, it has not been used as an optimization tool in the field of mechanical design. We solve three problems in kinematic synthesis using simulated annealing and the results show that the method is fast and obtains solutions at least as good as and in some cases better than those obtained by conventional optimization techniques.

Download Full-text