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    A multiobjective integrated multiproject scheduling and multiskilled workforce assignment model considering learning effect under uncertainty

    , Article Computational Intelligence ; Volume 36, Issue 1 , February , 2020 , Pages 276-296 Hematian, M ; Seyyed Esfahani, M. M ; Mahdavi, I ; Mahdavi Amiri, N ; Rezaeian, J ; Sharif University of Technology
    Blackwell Publishing Inc  2020
    Abstract
    Today, organizations try to decline academically expenses using humans and resources in addition to rising managers and operators' satisfaction. Meantime, a very important step in the process of decision is the assignment of human resources, particularly in connection with research and development (R&D) projects in which the system is highly dependent on the capabilities of human resources. In this study, we tried all the assumptions that come true in the real world, considered a model for applied R&D projects to reduce costs and increase the efficiency of projects. Therefore, an integrated multiproject scheduling and multiskill human resource assignment model under uncertainty has developed... 

    Reliable design of a forward/reverse logistics network under uncertainty: A robust-M/M/c queuing model

    , Article Transportation Research Part E: Logistics and Transportation Review ; Volume 48, Issue 6 , 2012 , Pages 1152-1168 ; 13665545 (ISSN) Vahdani, B ; Tavakkoli Moghaddam, R ; Modarres, M ; Baboli, A ; Sharif University of Technology
    2012
    Abstract
    This paper presents a novel model for designing a reliable network of facilities in closed-loop supply chain under uncertainty. For this purpose, a bi-objective mathematical programming formulation is developed which minimizes the total costs and the expected transportation costs after failures of facilities of a logistics network. To solve the model, a new hybrid solution methodology is introduced by combining robust optimization approach, queuing theory and fuzzy multi-objective programming. Computational experiments are provided for a number of test problems using a realistic network instance  

    Selection of wastewater treatment process based on the analytical hierarchy process and fuzzy analytical hierarchy process methods

    , Article Iranian Journal of Environmental Health Science and Engineering ; Volume 8, Issue 2 , 2011 , Pages 267-280 ; 17351979 (ISSN) Karimi, A. R ; Mehrdadi, N ; Hashemian, S. J ; Nabi Bidhendi, G. R ; Moghaddam, R. T ; Sharif University of Technology
    2011
    Abstract
    This paper presents an application of the analytical hierarchy process and fuzzy analytical hierarchy process methods for selecting the best wastewater treatment process. The analytical hierarchy process is one of the best ways for deciding among the complex criteria structure in different levels, and the fuzzy analytical hierarchy process is a synthetic extension of the classical method when the fuzziness of the decision makers are considered. After reviewing aerobic treatment processes operated in Iran's industrial estates and determining the main criteria used for treatment process evaluation, they are arranged in a hierarchy structure. Selection of the best wastewater treatment process... 

    Tourist arrival forecasting by evolutionary fuzzy systems

    , Article Tourism Management ; Volume 32, Issue 5 , 2011 , Pages 1196-1203 ; 02615177 (ISSN) Hadavandi, E ; Ghanbari, A ; Shahanaghi, K ; Abbasian Naghneh, S ; Sharif University of Technology
    Abstract
    Accurate forecasts of tourist arrivals and study of the tourist arrival patterns are essential for the tourism-related industries to formulate efficient and effective strategies on maintaining and boosting tourism industry in a country. Forecasting accuracy is one of the most important factors involved in selecting a forecasting method. This study presents a hybrid artificial intelligence (AI) model to develop a Mamdani-type fuzzy rule-based system to forecast tourist arrivals with high accuracy. The hybrid model uses genetic algorithm for learning rule base and tuning data base of fuzzy system. Actually it extracts useful information patterns with a descriptive rule induction approach based... 

    Thirty-nine years of Iran's scientific products in the field of Geophysics

    , Article Journal of the Earth and Space Physics ; Volume 41, Issue 1 , 2015 , Pages 145-164 ; 03781046 (ISSN) Asadi, M ; Ghaderi Sohi, A ; Sharif University of Technology
    Institute of Geophysics  2015
    Abstract
    Identifying and measuring the impact and value of scientific output plays an important role in today's world of information overload. On one side, governments are trying to distribute research funds in ways that support research in strategically important fields, on the other side, researchers and scientists are seeking to access only relevant and quality information that have mainly worthy of their attention. Nowadays, countries are evaluated not only by their national products, military power, geographical area, etc., but also by such factors as the production and consumption of scientific information. Scientometric approaches are used to provide appropriate tools for evaluating scientific... 

    Circular economy adoption barriers: An extended fuzzy best–worst method using fuzzy DEMATEL and Supermatrix structure

    , Article Business Strategy and the Environment ; Volume 31, Issue 4 , 2022 , Pages 1566-1586 ; 09644733 (ISSN) Govindan, K ; Khalili Nasr, A ; Karimi, F ; Mina, H ; Sharif University of Technology
    John Wiley and Sons Ltd  2022
    Abstract
    In the real world, there are complex decision-making problems in which a variety of intertwined factors and hierarchical structures exist, and it is difficult or impossible to solve these problems using classical methods. The prioritization of circular economy (CE) adoption barriers is one such complex problem that cannot be solved using current classical methods. Hence, in this paper, for the first time, a new method, namely, FBWDS, is developed. FBWDS derives from the combination of fuzzy best–worst method (BWM), fuzzy decision-making trial and evaluation laboratory (DEMATEL), and Supermatrix structure. This proposed method establishes weights of the intertwined factors in hierarchical... 

    Possibilistic Linear Programming and its Comparison with Stochastic Programming in Portfolio Selection Problem

    , M.Sc. Thesis Sharif University of Technology Asasian Kolur, Mehdi (Author) ; Mahdavi Amiri, Nezamoddin (Supervisor)
    Abstract
    In recent decades fuzzy linear programming and possiblistic linear programming models have been considered as strong tools for modeling uncertainty of problems. Here, after describing the possibility theory and considering the fuzzy relations with respect to possiblistic programming, we consider some models of fuzzy linear programming and its possiblistic model. Then, some of stochastic linear programming are discussed. After explanning the portfolio selection problem, we analyz and compare the numerical results of these two kinds of linear programming approaches. Finally using MATLAB software enviroment, the algorithms are implemented and tested  

    Integrated approach for land use suitability analysis

    , Article International Agrophysics ; Volume 25, Issue 4 , 2011 , Pages 311-318 ; 02368722 (ISSN) Abbaspour, M ; Mahiny, A. S ; Arjmandy, R ; Naimi, B ; Sharif University of Technology
    2011
    Abstract
    An integrated fuzzy spatial multi-criteria evaluation and analytic hierarchy process within a GIS was applied to assess the land use suitability for agriculture in Golestan province, Iran. In this way, a type of multi-criteria evaluation method called weighted linear combination in a spatial domain was employed to incorporate six factors and three constraining criteria into the evaluation of land use suitability for agriculture. A fuzzy set methodology was used to calculate values of a membership function of each factor. The relative importance weights of factors were estimated using analytic hierarchy proces. The application of the presented approach in Golestan province indicated that the... 

    Selection of wastewater treatment process based on the analytical hierarchy process and fuzzy analytical hierarchy process methods

    , Article International Journal of Environmental Science and Technology ; Volume 8, Issue 2 , March , 2011 , Pages 267-280 ; 17351472 (ISSN) Karimi, A. R ; Mehrdadi, N ; Hashemian, S. J ; Nabi Bidhendi, G. R ; Tavakkoli Moghaddam, R ; Sharif University of Technology
    2011
    Abstract
    This paper presents an application of the analytical hierarchy process and fuzzy analytical hierarchy process methods for selecting the best wastewater treatment process. The analytical hierarchy process is one of the best ways for deciding among the complex criteria structure in different levels, and the fuzzy analytical hierarchy process is a synthetic extension of the classical method when the fuzziness of the decision makers are considered. After reviewing aerobic treatment processes operated in Iran's industrial estates and determining the main criteria used for treatment process evaluation, they are arranged in a hierarchy structure. Selection of the best wastewater treatment process... 

    Fuzzy modeling techniques and artificial neural networks to estimate annual energy output of a wind turbine

    , Article Renewable Energy ; Volume 35, Issue 9 , September , 2010 , Pages 2008-2014 ; 09601481 (ISSN) Jafarian, M ; Ranjbar, A. M ; Sharif University of Technology
    2010
    Abstract
    The purpose of this article is to develop a new method to estimate annual energy output for a given wind turbine in any region which should be easy to use and has satisfactory accuracy. To do this, hourly wind speeds of 25 different stations in Netherlands, output power curve of S47 wind turbine and fuzzy modeling techniques and artificial neural networks were used and a model is developed to estimate annual energy output for S47 wind turbine in different regions. Since this model has three inputs (average wind speed, standard deviation of wind speed, and air density of that region), this model is easy to use. The accuracy of this method is compared with the accuracy of conventional methods... 

    Long-term prediction of solar and geomagnetic activity daily time series using singular spectrum analysis and fuzzy descriptor models

    , Article Earth, Planets and Space ; Volume 61, Issue 9 , 2009 , Pages 1089-1101 ; 13438832 (ISSN) Mirmomeni, M ; Kamaliha, E ; Shafiee, M ; Lucas, C ; Sharif University of Technology
    Abstract
    Of the various conditions that affect space weather, Sun-driven phenomena are the most dominant. Cyclic solar activity has a significant effect on the Earth, its climate, satellites, and space missions. In recent years, space weather hazards have become a major area of investigation, especially due to the advent of satellite technology. As such, the design of reliable alerting and warning systems is of utmost importance, and international collaboration is needed to develop accurate short-term and long-term prediction methodologies. Several methods have been proposed and implemented for the prediction of solar and geomagnetic activity indices, but problems in predicting the exact time and... 

    Robust-fuzzy model for supplier selection under uncertainty: an application to the automobile industry

    , Article Scientia Iranica ; Volume 25, Issue 4 , 2018 , Pages 2297-2311 ; 10263098 (ISSN) Rabieh, M ; Modarres, M ; Azar, A ; Sharif University of Technology
    Sharif University of Technology  2018
    Abstract
    This paper proposes an innovative robust-fuzzy method for multi-objective, multi-period supplier selection problem under multiple uncertainties. This approach integrates robust optimization and fuzzy programming. Uncertain parameters are modeled as random variables that take value within a symmetrical interval. However, due to the complexity or ambiguity of some real world problems and especially the nature of some of the available input data, the length of interval is also highly uncertain. This ambiguity motivated us to present a new approach, which could be applicable to multiple uncertainties conditions. Thus, in our approach, the half-length of these intervals is also represented by... 

    An efficient content-based video coding method for distance learning applications

    , Article Scientia Iranica ; Volume 16, Issue 2 D , 2009 , Pages 85-103 ; 10263098 (ISSN) Lotfi, T ; Bagheri, M ; Darabi, A. A ; Kasaei, S ; Sharif University of Technology
    2009
    Abstract
    This paper presents a novel method for cooperative educational dissemination systems. Taking into consideration the inherent characteristics of distance learning video streams (existence of a few slow moving objects in a classroom), we have proposed a novel content-based video coding method that is very efficient at low bitrate channels. On the encoding side, we have applied a background subtraction algorithm for motion segmentation using a novel statistical background modeling approach. At each frame, the moving objects are extrapolated with a rectangular model and tracked frame by frame (which forms the only data needed to be sent over the channel). On the decoding side, we have used a new... 

    A decision support system for demand management in healthcare supply chains considering the epidemic outbreaks: A case study of coronavirus disease 2019 (COVID-19)

    , Article Transportation Research Part E: Logistics and Transportation Review ; Volume 138 , June , 2020 Govindan, K ; Mina, H ; Alavi, B ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    The disasters caused by epidemic outbreaks is different from other disasters due to two specific features: their long-term disruption and their increasing propagation. Not controlling such disasters brings about severe disruptions in the supply chains and communities and, thereby, irreparable losses will come into play. Coronavirus disease 2019 (COVID-19) is one of these disasters that has caused severe disruptions across the world and in many supply chains, particularly in the healthcare supply chain. Therefore, this paper, for the first time, develops a practical decision support system based on physicians' knowledge and fuzzy inference system (FIS) in order to help with the demand... 

    Optimum synthesis of fuzzy logic controller for trajectory tracking by differential evolution

    , Article Scientia Iranica ; Vol. 18, Issue 2 B , 2011 , pp. 261-267 ; ISSN: 10263098 Nejat Pishkenari, H ; Mahboobi, S. H ; Alasty, A ; Sharif University of Technology
    Abstract
    Differential Evolution (DE) and Genetic Algorithms (GA) are population based search algorithms that come under the category of evolutionary optimization techniques. In the present study, these evolutionary methods have been utilized to conduct the optimum design of a fuzzy controller for mobile robot trajectory tracking. Comparison between their performances has also been conducted. In this paper, we will present a fuzzy controller to the problem of mobile robot path tracking for a CEDRA rescue robot. After designing the fuzzy tracking controller, the membership functions will be optimized by evolutionary algorithms in order to obtain more acceptable results  

    Integration of adaptive neuro-fuzzy inference system, neural networks and geostatistical methods for fracture density modeling

    , Article Oil and Gas Science and Technology ; Vol. 69, issue. 7 , 2014 , pp. 1143-1154 ; ISSN: 12944475 Jafari, A ; Kadkhodaie-Ilkhchi, A ; Sharghi, Y ; Ghaedi, M ; Sharif University of Technology
    Abstract
    Image logs provide useful information for fracture study in naturally fractured reservoir. Fracture dip, azimuth, aperture and fracture density can be obtained from image logs and have great importance in naturally fractured reservoir characterization. Imaging all fractured parts of hydrocarbon reservoirs and interpreting the results is expensive and time consuming. In this study, an improved method to make a quantitative correlation between fracture densities obtained from image logs and conventional well log data by integration of different artificial intelligence systems was proposed. The proposed method combines the results of Adaptive Neuro-Fuzzy Inference System (ANFIS) and Neural... 

    A joint model of destination and mode choice for urban trips: A disaggregate approach

    , Article Transportation Planning and Technology ; Volume 36, Issue 8 , Jul , 2013 , Pages 703-721 ; 03081060 (ISSN) Seyedabrishami, S ; Shafahi, Y ; Sharif University of Technology
    2013
    Abstract
    Trip destination and mode choice are highly influenced by travelers' perceptions and behaviors; selecting a destination and a vehicle for a trip are two interdependent problems. This paper presents and applies a disaggregate joint model for traveler destination and mode choice. The choice model uses fuzzy set and probability theory to deal with the uncertainty embedded in travelers' perceptions and behaviors. The model is structured as a decision tree in which the fuzzy and non-fuzzy classification of influential variables regarding destination selection and mode choice expand the tree. The most influential explanatory variables among all the variables categorized for travelers' household,... 

    Analyzing price, warranty length, and service capacity under a fuzzy environment: Genetic algorithm and fuzzy system

    , Article Scientia Iranica ; Volume 20, Issue 3 , 2013 , Pages 975-982 ; 10263098 (ISSN) Mahmoudi, A ; Shavandi, H ; Sharif University of Technology
    2013
    Abstract
    In this article, we propose a bi-objective model for the pricing-queuing problem under a fuzzy environment. We consider two objectives: maximizing the profit function and minimizing the waiting time in queue. Imagine a firm which sells a product in a channel providing after sales services. The sales price and warranty length affect customer demand. We formulate the demand function as a fuzzy system considering the sales price and warranty length. The firm optimizes the sales price and warranty length, as well as waiting time, in the queue of after sales services, to maximize its revenues and minimize waiting time. To solve the derived model, we develop a hybrid solution method of a fuzzy... 

    Ranking the sawability of ornamental stone using Fuzzy Delphi and multi-criteria decision-making techniques

    , Article International Journal of Rock Mechanics and Mining Sciences ; Volume 58 , 2013 , Pages 118-126 ; 13651609 (ISSN) Mikaeil, R ; Ozcelik, Y ; Yousefi, R ; Ataei, M ; Mehdi Hosseini, S ; Sharif University of Technology
    2013
    Abstract
    The main purpose of this study is to compare the many different rock properties in the rock sawability. The comparison was realized with the combination of the analytic hierarchy process (AHP) and Fuzzy Delphi method and also TOPSIS method. The analysis is one of the multi-criteria techniques providing useful support in selecting among several alternatives with different objectives and criteria. FDAHP method was used in determining the weights of the criteria by decision makers and then ranking the sawability of the rocks was determined by TOPSIS method. The study was supported by the results obtained from a questionnaire carried out to know the opinions of the experts in this subject.... 

    An adaptive neural network-fuzzy linear regression approach for improved car ownership estimation and forecasting in complex and uncertain environments: The case of Iran

    , Article Transportation Planning and Technology ; Volume 35, Issue 2 , 2012 , Pages 221-240 ; 03081060 (ISSN) Azadeh, A ; Neshat, N ; Rafiee, K ; Zohrevand, A. M ; Sharif University of Technology
    Abstract
    This paper applies a novel adaptive approach consisting of Artificial Neural Network (ANN) and Fuzzy Linear Regression (FLR) to improve car ownership forecasting in complex, ambiguous, and uncertain environments. This integrated approach is applied to forecast car ownership in Iran from 1930 to 2007. In this study, the level of car ownership is viewed as the result of demographic, politico-social, and urban structure factors including average family size, total population density, urban population density, urbanization rate, gross national product per capita, gasoline price, and total road length. To capture the potential complexity, uncertainty, and linearity relation between the car...