• فهرست مقالات vibration damping

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        1 - A Multi-supplier Inventory Model with Permissible Delay in Payment and ‎Discount
        M. Farhangi E. Mehdizadeh
        ‎This paper proposes a multi-supplier multi-product inventory model in which the suppliers have unlimited production capacity, allow delayed payment, and offer either an all-unit or incremental discount. The retailer can delay payment until after they have sold all چکیده کامل
        ‎This paper proposes a multi-supplier multi-product inventory model in which the suppliers have unlimited production capacity, allow delayed payment, and offer either an all-unit or incremental discount. The retailer can delay payment until after they have sold all the units of the purchased product. The retailer’s warehouse is limited, but the surplus can be stored in a rented warehouse at a higher holding cost. The demand over a finite planning horizon is known. This model aims to choose the best set of suppliers and also seeks to determine the economic order quantity allocated to each supplier. The model will be formulated as a mixed integer and nonlinear programming model which is NP-hard and will be solved by using genetic algorithm (GA), simulated annealing (SA) algorithm, and vibration damping optimization (VDO) algorithm. Finally, the performance of the algorithms will be ‎compared.‎ پرونده مقاله
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        2 - توسعه و حل یک مدل تعیین اندازه انباشته دو سطحی با چند روش تولید بوسیله الگوریتم‌ بهینه سازی میرایی ارتعاش
        محمد ابراهیمی مقصود امیری
        مسئله تعیین اندازه انباشته شامل تعیین مقدار محصول و زمان بندی برای چندین قلم بر روی یک واحد تسهیل با بیش از یک تعداد متناهی از دوره به طوری که تقاضا و ظرفیت محدود می تواند با حداقل هزینه ارضا شود، می باشد. در این مقاله، یک مدل تعیین اندازه انباشته دو سطحی با چند روش تول چکیده کامل
        مسئله تعیین اندازه انباشته شامل تعیین مقدار محصول و زمان بندی برای چندین قلم بر روی یک واحد تسهیل با بیش از یک تعداد متناهی از دوره به طوری که تقاضا و ظرفیت محدود می تواند با حداقل هزینه ارضا شود، می باشد. در این مقاله، یک مدل تعیین اندازه انباشته دو سطحی با چند روش تولید ارائه می شود. هدف مدل ارائه شده مینیمم سازی هزینه می باشد. از الگوریتم بهینه سازی میرایی ارتعاش برای حل مدل استفاده می شود. از آنجایی که کیفیت حل همه الگوریتم های فرا ابتکاری به پارامترهای آن ها وابسته است، برای تنظیم پارامتر الگوریتم میرایی ارتعاش از روش تاگوچی استفاده شده است. سپس برای اثبات عملکرد مناسب روش حل ارائه شده، ابتدا مسائل آزمایشی با ابعاد مختلف تولید شده و سپس توسط نرم افزار لینگو و الگوریتم بهینه سازی میرایی ارتعاش حل گردید. در نهایت پاسخ لینگو و الگوریتم بهینه سازی میرایی ارتعاش را با هم از نظر زمان حل مقایسه می کنیم که نتایج بدست آمده نشان می دهد، جواب الگوریتم بهینه سازی میرایی ارتعاش در مسائل با اندازه بزرگ کیفیت بهتری نسبت لینگو داشته است. پرونده مقاله
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        3 - Three Metaheuristic Algorithms for Solving the Multi-item Capacitated Lot-sizing Problem with Product Returns and Remanufacturing
        Esmaeil Mehdizadeh Amir Fatehi Kivi
        This paper proposes a new mixed integer programming model for multi-item capacitated lot-sizing problem with setup times, safety stock and demand shortages in closed-loop supply chains. The returned products from customers can either be disposed or be remanufactured to چکیده کامل
        This paper proposes a new mixed integer programming model for multi-item capacitated lot-sizing problem with setup times, safety stock and demand shortages in closed-loop supply chains. The returned products from customers can either be disposed or be remanufactured to be sold as new ones again. Due to the complexity of problem, three meta-heuristics algorithms named simulated annealing (SA) algorithm, vibration damping optimization (VDO) algorithm and harmony search (HS) algorithm have been used to solve this model. Additionally, Taguchi method is conducted to calibrate the parameter of the meta-heuristics and select the optimal levels of the algorithm’s performance influential factors. To verify and validate the efficiency of the proposed algorithms in terms of solution quality, the obtained results were compared with those obtained from Lingo 8 software for a different problem. Finally, computational results of these algorithms were compared and analyzed by producing and solving some small, medium and large-size test problems. The results confirmed the efficiency of the HS algorithm against the other methods. پرونده مقاله
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        4 - A New Hybrid Algorithm to Optimize Stochastic-fuzzy Capacitated Multi-Facility Location-allocation Problem
        Esmaeil Mehdizadeh Mohammad Reza Tavarroth Vahid Hajipour
        Facility location-allocation models are used in a widespread variety of applications to determine the number of required facility along with the relevant allocation process. In this paper, a new mathematical model for the capacitated multi-facility location-allocation p چکیده کامل
        Facility location-allocation models are used in a widespread variety of applications to determine the number of required facility along with the relevant allocation process. In this paper, a new mathematical model for the capacitated multi-facility location-allocation problem with probabilistic customer's locations and fuzzy customer’s demands under the Hurwicz criterion is proposed. This model is formulated as α-cost minimization model according to different criteria. Since our problem is strictly Np-hard, a new hybrid intelligent algorithm is presented to solve the stochastic-fuzzy model. The proposed algorithm is based on a vibration damping optimization (VDO) algorithm which is combined with the simplex algorithm and fuzzy simulation (SFVDO). Finally, a numerical example is presented to illustrate the capability of the proposed solving methodologies. پرونده مقاله