در این مقاله یک مسأله برنامه ریزی چند هدفه کسری خطی با متغیرها و بردار منابع فازی مورد مطالعه قرار می گیرد و الگوریتمی با رویکرد پارامتری جهت حل آن ارائه می شود. فرآیند حل پیشنهاد شده برای تعیین جواب بهینه مسأله مبتنی بر رویکرد پارامتری خواهد بود که این امر ضمن انطباق بیشتر جواب با واقعیت، اطلاعات جامع تری را در اختیار تصمیم گیرنده قرار خواهد داد. سادگی روش مطرح شده یکی از مزیت های الگوریتم پیشنهادی است که امکان درک مطلوب تر فرآیند حل را توسط کاربر فراهم می آورد. همچنین جهت توصیف فرآیند حل روش پیشنهاد شده، یک مثال عددی ارائه می شود.

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تکنولوژی تحلیل پوششی داده‌ها کاربردی گسترده در اندازه‌گیری کارایی واحدهای همگن با عوامل ورودی و خروجی چندگانه دارد. این عوامل ممکن است در شرایط عدم قطعیت بویژه در محیط‌های فازی یا تصادفی تعیین گردند. از این رو در توسیع مدل‌های استاندارد DEA به محیط‌های دو ترکیبی تصادفی فازی، بخشی از ساختار طبیعی DEA ممکن است تغییر یابد. به عنوان مثال خطی بودن، شدنی بودن و یا قرار نگرفتن مقادیر کارایی (ورودی محور) در فاصله 0 تا 1 از جمله این موارد می‌باشند. در این مقاله، رویکرد جدیدی مبتنی بر آلفا برش‌ها برای ارزیابی کارایی واحد‌های تصمیم‌گیرنده در مدل‌های تحلیل پوششی داده‌ها با ورودی‌ها و خروجی‌ها تصادفی فازی ارائه می‌شود. رویکرد پیشنهادی ضمن ارائه روش جدید در حل مساله DEA با پارامترهای تصادفی فازی، به اصلاح موارد یاد شده می‌پردازد. همچنین، یک مثال عددی به اعتبار سنجی و ویژگی‌های مدل پیشنهادی می‌پردازد. Manuscript profile

In the process of milk production, the highest cost relates to animal feed. Based on reports provided by the experts, around seventy percent of dairy livestock costs included feed costs. In order to minimize the total price of livestock feed, according to the limits of feed sources in each region or season, and also the transportation and maintenance costs and ultimately milk price reduction, optimization of the livestock nutrition program is an essential issue. Because of the uncertainty and lack of precision in the optimal food ration done with existing methods based on linear programming, there is a need to use appropriate methods to meet this purpose. Therefore, in this study formulation of completely mixed nutrient diets of dairy cows is done by using a fuzzy linear programming in early lactation. Application of fuzzy optimization method and floating price make it possible to formulate and change the completely mixed diets with adequate safety margins. Therefore, applications of fuzzy methods in feed rations of dairy cattle are recommended to optimize the diets. Obviously, it would be useful to design suitable software, which provides the possibility of using floating prices to set feed rations by the use of fuzzy optimization method. Manuscript profile

In this research, the multi-objective project management decision problem with fuzzy goals and fuzzy constraints are considered. We constitute α-cut approach and two various fuzzy goal programming solution methods for solving the Multi-Objective Project Management (MOPM) decision problem under fuzzy environments. The Interactive fuzzy multi-objective linear programming (i-FMOLP) and Weighted Additive approaches are proposed for solving multi-objective PM decision problem where fuzzy information are demonstrated by using linear membership functions (LMF). The proposed approaches effort contemporarily to minimize the total project costs, total completion time and total crashing costs and the several constraints such as the time between events i and j, the crashing time for activity (i,j) and the total budget capital. The weight of criteria for each objective function base on project DM preference degree computed with Fuzzy AHP technique. The performance analysis calculated with a set of distance metric for i-FMOLP and Weighted Additive solution methods that represent uncertainty goals and constraints in PM decision problem with ideal solution in an industrial case study is compared. Manuscript profile

Irrigation water management is crucial for agricultural production and livelihood security in many regions and countries throughout the world. Over the past decades, controversial and conflictladen water-allocation issues among competing municipal, industrial and agricultural interests have raised increasing concerns. Particularly, growing population, varying natural conditions and shrinking water availabilities have exacerbated such competitions. Shrinking water availabilities can result in reduced water supplies, while growing population can lead to increased water demands, these two facts can further intensify the water shortage. Stochastic programming methodology is applied in this paper to a capital investment problem in water resources. A framework is offered for the evaluation of electricity generation and water supply for agricultural irrigation. This essessment is conducted through the construction of an appropriate stochastic optimization model. A recursive least squares algorithm is incorp-orated in the model which enablee more accurate estimation of model parameters. Manuscript profile

In this paper, Chebyshev acceleration technique is used to solve the fuzzy linear system (FLS). This method is discussed in details and followed by summary of some other acceleration techniques. Moreover, we show that in some situations that the methods such as Jacobi, Gauss-Sidel, SOR and conjugate gradient is divergent, our proposed method is applicable and the acquired results are illustrated by some numerical examples. Manuscript profile

Ranking fuzzy numbers plays a very important role in linguistic decision making and other fuzzy application systems. In spite of many ranking methods, no one can rank fuzzy numbers with human intuition consistently in all cases. Shortcoming are found in some of the convenient methods for ranking triangular fuzzy numbers such as the coefficient of variation (CV index), distance between fuzzy sets, centroid point and original point, and also weighted mean value. In this paper, we introduce a new method for ranking triangular fuzzy number to overcome the shortcomings of the previous techniques. Finally, we compare our method with some convenient methods for ranking fuzzy numbers to illustrate the advantage our method. Manuscript profile

Many ranking methods have been proposed so far. However, there is yet no method that can always give a satisfactory solution to every situation; some are counterintuitive, not discriminating; some use only the local information of fuzzy values; some produce different ranking for the same situation. For overcoming the above problems, we propose a new method for ranking fuzzy quantities based on the distance method. Then, an application of using fuzzy ordering in the fuzzy mathematical programming as well as fuzzy primal simplex algorithm is indicated. In particular, we emphasize that the fuzzy ordering will be useful when a decision maker needs to evaluate the optimality condition in any solving process. Manuscript profile