Heuristics and Metaheuristics Algorithms
Mehdi Khadem; Abbas Toloie Eshlaghy; kiamars Fathi Hafshejani
Abstract
Over the past decade, solving complex optimization problems with metaheuristic algorithms has attracted many experts and researchers.There are exact methods and approximate methods to solve optimization problems. Nature has always been a model for humans to draw the best mechanisms and the best engineering ...
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Over the past decade, solving complex optimization problems with metaheuristic algorithms has attracted many experts and researchers.There are exact methods and approximate methods to solve optimization problems. Nature has always been a model for humans to draw the best mechanisms and the best engineering out of it and use it to solve their problems. The concept of optimization is evident in several natural processes, such as the evolution of species, the behavior of social groups, the immune system, and the search strategies of various animal populations. For this purpose, the use of nature-inspired optimization algorithms is increasingly being developed to solve various scientific and engineering problems due to their simplicity and flexibility. Anything in a particular situation can solve a significant problem for human society. This paper presents a comprehensive overview of the metaheuristic algorithms and classifications in this field and offers a novel classification based on the features of these algorithms.
Supply chain management
Hamidreza Mahmoudi; Morteza Bazrafshan; Mohadeseh Ahmadipour
Abstract
In this paper, a framework for optimizing the oil condensate supply chain is modeled using mathematical planning to design and make strategic and tactical decisions. According to this framework, investment and operating costs for oil and gas transmission lines can be minimized to meet the pressure requirements ...
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In this paper, a framework for optimizing the oil condensate supply chain is modeled using mathematical planning to design and make strategic and tactical decisions. According to this framework, investment and operating costs for oil and gas transmission lines can be minimized to meet the pressure requirements and the transmission network. Also, we can minimize the production of pollutants in the chain-related sectors. In the case under study, all possible decisions are considered to consider the environmental aspects of the supply chain. Therefore, the structure and decisions of the supply chain are generally based on two objective functions, including reducing transmission and maintenance costs and pollution in treatment plants and distribution centers. The proposed model is 95% reliable, which is acceptable reliability, and can estimate goals with only 5% error. Using the proposed model will reduce costs by 31% and emissions by 51%. Also, there will be an 8% increase in the capacity of fields and refineries and an increase in exports by 65%. Using the results obtained from solving the model, we can determine the share of each petroleum product in the cost and each part of the chain in the production of greenhouse gases. According to the results, fuel oil has the highest and oils the lowest. In addition, refineries have the greatest impact, and storage tanks have the least impact on environmental pollution.
Engineering Optimization
Okwuchi Smith Onyekwere; Mobolaji Humphrey Oladeinde; Kindness Alfred Uyanga
Abstract
There is great interest in application of natural fibres, such as bamboo fibre, as reinforcement in composite production. Herein, to achieve high performance under optimum process conditions, experimental design and optimization techniques are used to investigate the best parameter settings for processing ...
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There is great interest in application of natural fibres, such as bamboo fibre, as reinforcement in composite production. Herein, to achieve high performance under optimum process conditions, experimental design and optimization techniques are used to investigate the best parameter settings for processing bamboo fibre polyester composites. Single response optimization of the properties of bamboo fibre polyester composites using Taguchi orthogonal array, analysis of variance and Post hoc test was carried out. The test samples comprised of untreated, mercerized, acetylated and mercerized-acetylated bamboo fibre composites at fibre contents of 10, 20, 30, 40, and 50 wt %. All composite samples were fabricated using conventional hand lay-up process on randomly oriented long bamboo fibres. It was found that optimum parameter setting for impact strength was achieved at mercerization treatment and 30wt% fibre content with impact strength of 158.23 J/cm. For flexural strength, optimum parameter setting was found to be mercerization treatment at 50 wt % level of fibre content which resulted to flexural strength of 62.7 MPa. The optimum parameter setting for tensile strength is observed at mercerized-acetylation treatment at 50 wt% fibre content with tensile strength of 72.96 MPa. However, no significant difference, (P <.005) was observed in flexural strength, tensile strength and impact strength of mercerized and mercerized-acetylated fibre composites. This study established a research approach to improve bamboo fibre composite properties for more extended applications and to obtain optimal operating conditions by using optimization techniques. It will also serve as a guide for composite manufacturers on parameter settings selection.
Operations Research
Saeed Khalili; Masood Mosadegh Khah
Abstract
This study presents a new mathematical optimization model using queuing theory to determine the hotel capacity in an optimal manner. For this purpose, a Knapsack model based on the queuing theory is proposed. In this regard, after simulating a hotel's reception system with the help of queuing models ...
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This study presents a new mathematical optimization model using queuing theory to determine the hotel capacity in an optimal manner. For this purpose, a Knapsack model based on the queuing theory is proposed. In this regard, after simulating a hotel's reception system with the help of queuing models and using a limited two-dimensional Knapsack model, the capacity and an optimum number of rooms are obtained. Since the proposed model is too complex on large scales, a modified Genetic Algorithm (GA) approach enhanced by Taguchi method is employed to solve the problem. The obtained results indicate that unlike previous studies, the proposed models can be applied to different scenarios.
