Multi Objectives Fuzzy Ant Colony Optimization Design of Supply Path Searching

One of problem faced in supply chain management is path searching. The best path depend not only on distance, but also other variables, such as: the quality of involved companies, quality of delivered product, and other value resulted by quality measurement. Commonly, the ant colony optimization could search the best path that has only one objective path. But it would be difficult to be adopted, because in the real case, the supply path has multi path and objectives (especially in palm oil based bioenergy supply). The objective of this paper is to improve the ant colony optimization for solving multi objectives based supply path problem by using fuzzy ant colony optimization. The developed multi objectives fuzzy ant colony optimization design was explained here, that it was used to search the best supply path. Salah satu masalah yang dihadapi dalam Supply Chain Management adalah pencarian jalur. Jalur terbaik tidak hanya tergantung pada jarak, tetapi juga variabel lain, seperti: kualitas Perusahaan yang terlibat, kualitas produk yang dikirimkan, dan nilai lain yang dipengaruhi oleh pengukuran kualitas. Umumnya, Ant Colony Optimization bisa mencari jalur terbaik yang hanya memiliki satu jalur objektif. Tapi akan sulit untuk diadopsi, karena dalam kasus nyata, jalur supply memiliki banyak jalur dan tujuan (khususnya pasokan minyak kelapa sawit berbasis bioenergi). Tujuan dari penelitian ini adalah untuk meningkatkan Ant Colony Optimization dalam menyelesaikan masalah jalur supply dengan menggunakan Fuzzy Ant Colony Optimization. Tujuan pengembangan Fuzzy Ant Colony Optimization dijelaskan disini, yaitu digunakan untuk mencari jalur supply terbaik

Genetic algorithms for satellite scheduling problems

Recently there has been a growing interest in mission operations scheduling problem. The problem, in a variety of formulations, arises in management of satellite/space missions requiring efficient allocation of user requests to make possible the communication between operations teams and spacecraft systems. Not only large space agencies, such as ESA (European Space Agency) and NASA, but also smaller research institutions and universities can establish nowadays their satellite mission, and thus need intelligent systems to automate the allocation of ground station services to space missions. In this paper, we present some relevant formulations of the satellite scheduling viewed as a family of problems and identify various forms of optimization objectives. The main complexities, due highly constrained nature, windows accessibility and visibility, multi-objectives and conflicting objectives are examined. Then, we discuss the resolution of the problem through different heuristic methods. In particular, we focus on the version of ground station scheduling, for which we present computational results obtained with Genetic Algorithms using the STK simulation toolkit.Peer ReviewedPostprint (published version

Application of simulated annealing to solve multi-objectives for aggregate production planning

Aggregate production planning (APP) is one of the most significant and complicated problems in production planning and aim to set overall production levels for each product category to meet fluctuating or uncertain demand in future and to set decision concerning hiring, firing, overtime, subcontract, carrying inventory level. In this paper, we present a simulated annealing (SA) for multi-objective linear programming to solve APP. SA is considered to be a good tool for imprecise optimization problems. The proposed model minimizes total production and workforce costs. In this study, the proposed SA is compared with particle swarm optimization (PSO). The results show that the proposed SA is effective in reducing total production costs and requires minimal time

Optimasi Site Layout Menggunakan Multi-objectives Function Pada Proyek Pembangunan Gedung Kuliah Terpadu Tahap III Politeknik Negeri Malang

Setiap proyek konstruksi harus ada fasilitas proyek (site facilities) untuk menunjang kinerja pekerja konstruksi. Tata letak fasilitas proyek harus menyesuaikan kebutuhan maupun keadaan/medan di lapangan.Fasilitas proyek (site facilities) pada proyek konstruksi berskala besar harus diimbangi dengan fasilitas kerja yang memadai dan efisien sehingga aktifitas pembangunan dapat berjalan lancar, nyaman serta mendukung program keselamatan dan kesehatan kerja (K3). Sistem manajemen keselamatan kerja sangat penting dalam proyek berskala besar, tingginya intensitas kegiatan yang ada di dalam proyek tersebut mengharuskan penempatan site facilities yang efisien, aman dan nyaman untuk pekerja konstruksi. Pada penelitian ini dilakukan pegoptimasian site layoutproyek dengan menggunakan analisis multi-objectives function yaitu analisis Traveling Distance (jarak tempuh) dan analisisSafety Index (tingkat keamanan dan keselamatan). Semakin kecil nilai traveling distance yang dihasilkan maka semakin dekat perjalanan pekerja untuk berpindah ke fasilitas proyek ke lain dan semakin kecil nilai safety index maka tingkat kecelakaan yang dialami pekerja yang melalui zona bahaya juga akan semakin kecil. Site layout yang paling optimal diketahui dari beberapa skenario pemindahan fasilitas proyek untuk mendapatkan site layout yang efisien. Dari identifikasi dari 4 skenario yang di analisa maka didapat nilai traveling distance paling minimum pada skenario 2 dengan nilai sebesar 59579,271 meter atau mengalami penurunan nilai traveling distance sebesar 0,96% dari kondisi eksisting. Untuk perhitungan nilai safety index diketahui bahwa nilai safety index minimum pada skenario 4 dengan nilai sebesar 809,606 atau mengalami penurunan nilai safety index sebesar 0,95% dari kondisi eksisting. Analisa site layout optimum dan memenuhi kriteria antara persentase 30% untuk nilai traveling distance dan 70% untuk nilai safety index adalah site layout pada skenario 4 dengan nilai total sebesar 1,041273

Catalytic-Dielectric Barrier Discharge Plasma Reactor For Methane and Carbon Dioxide Conversion

A catalytic - DBD plasma reactor was designed and developed for co-generation of synthesis gas and C2+ hydrocarbons from methane. A hybrid Artificial Neural Network - Genetic Algorithm (ANN-GA) was developed to model, simulate and optimize the reactor. Effects of CH4/CO2 feed ratio, total feed flow rate, discharge voltage and reactor wall temperature on the performance of catalytic DBD plasma reactor was explored. The Pareto optimal solutions and corresponding optimal operating parameters ranges based on multi-objectives can be suggested for catalytic DBD plasma reactor owing to two cases, i.e. simultaneous maximization of CH4 conversion and C2+ selectivity, and H2 selectivity and H2/CO ratio. It can be concluded that the hybrid catalytic DBD plasma reactor is potential for co-generation of synthesis gas and higher hydrocarbons from methane and carbon dioxide and showed better than the conventional fixed bed reactor with respect to CH4 conversion, C2+ yield and H2 selectivity for CO2 OCM process

Optimal sizing of C-type passive filters under non-sinusoidal conditions

In the literature, much attention has been focused on power system harmonics. One of its important effects is degradation of the load power factor. In this article, a C-type filter is used for reducing harmonic distortion, improving system performance, and compensating reactive power in order to improve the load power factor while taking into account economic considerations. Optimal sizing of the C-type filter parameters based on maximization of the load power factor as an objective function is determined. The total installation cost of the C-type filter and that of the conventional shunt (single-tuned) passive filter are comparatively evaluated. Background voltage and load current harmonics are taken into account. Recommendations defined in IEEE standards 519-1992 and 18-2002 are taken as the main constraints in this study. The presented design is tested using four numerical cases taken from previous publications, and the proposed filter results are compared with those of other published techniques. The results validate that the performance of the C-type passive filter as a low-pass filter is acceptable, especially in the case of lower short-circuit capacity systems. The C-type filter may achieve the same power factor with a lower total installation cost than a single-tuned passive filter

Facility layout problem: Bibliometric and benchmarking analysis

Facility layout problem is related to the location of departments in a facility area, with the aim of determining the most effective configuration. Researches based on different approaches have been published in the last six decades and, to prove the effectiveness of the results obtained, several instances have been developed. This paper presents a general overview on the extant literature on facility layout problems in order to identify the main research trends and propose future research questions. Firstly, in order to give the reader an overview of the literature, a bibliometric analysis is presented. Then, a clusterization of the papers referred to the main instances reported in literature was carried out in order to create a database that can be a useful tool in the benchmarking procedure for researchers that would approach this kind of problems