Iranian Journal of Fuzzy SystemsIranian Journal of Fuzzy Systems
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Feed provided by Iranian Journal of Fuzzy Systems. Click to visit.(1709-3931) COMPLEX FUZZY Hv-SUBGROUPS OF AN Hv-GROUP
http://ijfs.usb.ac.ir/article_4556_0.html
The concept of complex fuzzy sets is a generalization of ordinaryfuzzy sets. In this paper, we introduce the concept of complex fuzzy subhy-pergroups (Hv-subgroups) as well as the concept of complex anti-fuzzy subhy-pergroups (Hv-subgroups). We investigate their properties and their relationswith the traditional fuzzy (anti-fuzzy) subhypergroups (Hv-subgroups), andwe prove some results in this respect.Mon, 08 Apr 2019 19:30:00 +0100cover 16-5 October 2019
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Mon, 30 Sep 2019 20:30:00 +0100(1803-4364)0ROUGH APPROXIMATION OPERATORS BASED ON QUANTALE-VALUED FUZZY GENERALIZED ...
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Let L be an integral and commutative quantale. In this paper,by fuzzifying the notion of generalized neighborhood systems, the notion of L-fuzzy generalized neighborhood system is introduced and then a pair of lowerand upper approximation operators based on it are dened and discussed. It isproved that these approximation operators include generalized neighborhoodsystem-based approximation operators, L-fuzzy relation-based approximationoperators and L-fuzzy covering-based approximation operators as their specialcircumstances. Therefore, the research on L-fuzzy generalized neighborhoodsystem-based approximation operators has more general significance. In ad-dition, when the L-fuzzy generalized neighborhood system is serial, reflexive,unary and transitive, then the corresponding approximation operators are dis-cussed and characterized, respectively.Mon, 08 Apr 2019 19:30:00 +0100Horizontal representation of a hesitant fuzzy set and its application to multiple attribute ...
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The main aim of this paper is to present a novel method for ranking hesitant fuzzy sets (HFSs) based on transforming HFSs into fuzzy sets (FSs). The idea behind the method is an interesting HFS decomposition which is referred here to as the horizontal representation in the current study. To show the validity of the proposed ranking method, we apply it to solve a multi-attribute decision-making problem under hesitant fuzzy environment.Interestingly, the results show that the proposedmethod gives the most accepted precedence of alternatives in comparison with the other existingmethods.Mon, 30 Sep 2019 20:30:00 +0100(1803-4353) WEAK HYPER SEMI-QUANTALES AND WEAK HYPERVALUED TOPOLOGICAL SPACES
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The purpose of this paper is to construct a weak hyper semiquantaleas a generalization of the concept of semi-quantale and used it as anappropriate hyperlattice-theoretic basis to formulate new lattice-valued topologicaltheories. Based on such weak hyper semi-quantale, we aim to constructthe notion of a weak hypervalued-topology as a generalized form of the socalledlattice-valued topology (or many-valued topology). Some properties ofweak hyper semi-quantales and weak hypervalued-topologies will be studied.An adjunction between the category of weak hyper semi-quantales and thecategory of weak hypervalued quasi-topological spaces will be established.Mon, 08 Apr 2019 19:30:00 +0100A research on classification performance of fuzzy classifiers based on fuzzy set theory
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Due to the complexities of objects and the vagueness of the human mind, it has attracted considerable attention from researchers studying fuzzy classification algorithms. In this paper, we propose a concept of fuzzy relative entropy to measure the divergence between two fuzzy sets. Applying fuzzy relative entropy, we prove the conclusion that patterns with high fuzziness are close to the classification boundary. Thus, it plays a great role in classification problems that patterns with high fuzziness are classified correctly. Meanwhile, we draw a conclusion that the fuzziness of a pattern and the uncertainty of its class label are equivalent. As is well known, entropy not only measures the uncertainty of random variable, but also represents the amount of information carried by the variable. Hence, a fuzzy classifier with high fuzziness would carry much information about training set. Therefore, in addition to some assessment criteria such as classification accuracy, we could study the classification performance from the perspective of the fuzziness of classifier. In order to try to ensure the objectivity in dealing with unseen patterns, we should make full use of information of the known pattern set and do not make too much subjective assumptions in the process of learning. Consequently, for problems with rather complex decision boundaries especially, under the condition that a certain training accuracy threshold is maintained, we demonstrate that a fuzzy classifier with high fuzziness would have a well generalization performance.Mon, 30 Sep 2019 20:30:00 +0100(1805-4476) Convex structures via convex L-subgroups of an L-ordered group
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In this paper, we first characterize the convex L-subgroup of an L-ordered group by means of four kinds of cut setsof an L-subset. Then we consider the homomorphic preimages and the product of convex L-subgroups. After that,we introduce an L-convex structure constructed by convex L-subgroups. Furthermore, the notion of the degree towhich an L-subset of an L-ordered group is a convex L-subgroup is proposed and characterized. An L-fuzzy convexstructure results from convex L-subgroup degree is imported naturally, and its L-fuzzy convexity preserving mappingsis investigated.Fri, 12 Apr 2019 19:30:00 +0100A note on decision making in medical investigations using new divergence measures for ...
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Srivastava and Maheshwari (Iranian Journal of Fuzzy Systems 13(1)(2016) 25-44) introduced a new divergence measure for intuitionisticfuzzy sets (IFSs). The properties of the proposed divergence measurewere studied and the efficiency of the proposed divergence measurein the context of medical diagnosis was also demonstrated. In thisnote, we point out some errors in the proving process of twoproperties of the proposed divergence measure. Then we give amodification of the proving process.Mon, 30 Sep 2019 20:30:00 +0100(1807-4621) Super- and sub-additive transformations of aggregation functions from the point of ...
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The way super- and sub-additive transformations of aggregation functions are introduced involve suprema and infimataken over simplexes whose dimensions may grow arbitrarily. Exact values of such transformations may thus be hardto determine in general. In this note we discuss methods of algorithmic approximation of such transformations.Fri, 12 Apr 2019 19:30:00 +0100Solving LR fuzzy linear matrix equationâ€
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In this paper, the fuzzy matrix equation $Awidetilde{X}B=widetilde{C}$ in which $A,B$ are $n times n$crisp matrices respectively and $widetilde{C}$ is an $n times n$ arbitrary LR fuzzy numbers matrix, is investigated. A new numerical procedure for calculating the fuzzy solution is designed and a sufficient condition for the existence of strong fuzzy solution is derived. Some examples are given to illustrate the proposed method.Mon, 30 Sep 2019 20:30:00 +0100(1806-4545) Regularity in residuated lattices
http://ijfs.usb.ac.ir/article_4569_0.html
In this paper, we study residuated lattices in order to give new characterizations for dense, regular andBoolean elements in residuated lattices and investigate special residuated lattices in order to obtain newcharacterizations for the directly indecomposable subvariety of Stonean residuated lattices. Free algebra invarieties of Stonean residuated lattices is constructed. We introduce in residuated lattice a new type of filtercalled special filter and investigate its properties. Finally, regular filter property in residuated lattices isintroduced and is studied in details.Fri, 12 Apr 2019 19:30:00 +0100Systematic literature review of fuzzy logic based text summarization
http://ijfs.usb.ac.ir/article_4906_626.html
Information Overloadrq is not a new term but with the massive development in technology which enables anytime, anywhere, easy and unlimited access; participation & publishing of information has consequently escalated its impact. Assisting userslq informational searches with reduced reading surfing time by extracting and evaluating accurate, authentic & relevant information are the primary concerns in the present milieu. Automatic text summarization is the process of condensing an original document into shorter form to create smaller, compact version from the abundant information that is available, preserving the content & meaning such that it meets the needs of the user. Though many summarization techniques have been proposed but there are no lq silver bulletsrq to achieve the superlative results as of human generated summaries. Thus, the domain of text summarization is an active and dynamic field of study, practice & research with the continuous need to expound novel techniques for achieving comparable & effectual results. Fuzzy logic has appeared as a powerful theoretical framework for studying human reasoning and its application has been explored within the domain of text summarization in the past few years. This paper is a systematic literature review to gather, analyze, and report the trends, gaps and prospects of using fuzzy logic for automatic text summarization on the basis of the findings in original studies.Mon, 30 Sep 2019 20:30:00 +0100(1806-4519) Negations and aggregation operators based on a new hesitant fuzzy partial ordering
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Based on a new hesitant fuzzy partial ordering proposed by Garmendia et al. [7], in this paper a fuzzy disjunction Don the set H of finite and nonempty subsets of the unit interval and a t-conorm S on the set ¯B of equivalence class onthe set of finite bags of unit interval based on this partial ordering are introduced respectively. Then, hesitant fuzzynegations Nn on H and μn on¯B are proposed. Particularly, their De Morgan's laws are investigated with respect to binary operations C and D on H, as well as T and S on ¯B respectively, where C is a commutative fuzzy conjunction on (H,≤H) and T is a t-norm on (¯B,≤B). Finally, the new hesitant fuzzy aggregation operators are presented on H and B and their more general forms are given. Moreover, the validity of the aggregation operations is illustrated by a numerical example on decision making.Fri, 12 Apr 2019 19:30:00 +0100Multi-granulation fuzzy probabilistic rough sets and their corresponding three-way decisions ...
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This article introduces a general framework of multi-granulation fuzzy probabilistic roughsets (MG-FPRSs) models in multi-granulation fuzzy probabilistic approximation space over twouniverses. Four types of MG-FPRSs are established, by the four different conditional probabilitiesof fuzzy event. For different constraints on parameters, we obtain four kinds of each type MG-FPRSsover two universes. To find a suitable way of explaining and determining these parameters in eachkind of each type MG-FPRS, three-way decisions (3WDs) are studied based on Bayesian minimum-riskprocedure, i.e., the decision-theoretic rough set (DTRS) approach. The main contribution of this paperis twofold. One is to extend the fuzzy probabilistic rough set (FPRS) to MG-FPRS model over two universes.Another is to present an approach to select parameters in MG-FPRS modeling by using the process ofdecision-making under conditions of risk.Mon, 30 Sep 2019 20:30:00 +0100(1809-4735) New distance and similarity measures for hesitant fuzzy soft sets
http://ijfs.usb.ac.ir/article_4571_0.html
The hesitant fuzzy soft set (HFSS), as a combination of hesitant fuzzy and soft sets, is regarded as a useful tool fordealing with the uncertainty and ambiguity of real-world problems. In HFSSs, each element is defined in terms ofseveral parameters with arbitrary membership degrees. In addition, distance and similarity measures are consideredas the important tools in different areas such as pattern recognition, clustering, medical diagnosis, and the like. Forthis purpose, the present study aimed to evaluate the distance and similarity measures for HFSSs by using well-knownHamming, Euclidean, and Minkowski distance measures. Further, some examples were used to demonstrate that thesemeasures fail to perform well in some applications. Accordingly, new distance and similarity measures were proposed byconsidering a hesitance index for HFSSs and the effect of considering hesitance index was shown by using an exampleof pattern recognition. Finally, the application of the proposed measures and hesitance index was investigated in theclustering and decision-making problem, respectively. In conclusion, the use of the proposed measures in clustering andhesitance index in decision-making can provide better and more reasonable results.Fri, 12 Apr 2019 19:30:00 +0100The KKT optimality conditions for constrained programming problem with generalized convex fuzzy ...
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The aim of present paper is to study a constrained programming with generalized $alpha-$univex fuzzy mappings. In this paper we introduce the concepts of $alpha-$univex, $alpha-$preunivex, pseudo $alpha-$univex and $alpha-$unicave fuzzy mappings, and we discover that $alpha-$univex fuzzy mappings are more general than univex fuzzy mappings. Then, we discuss the relationships of generalized $alpha-$univex fuzzy mappings and get some properties. In the last, we derive necessary and sufficient Karush-Kuhn-Tucker conditions and its dual problems with generalized differentiable $alpha-$univex fuzzy mappings for fuzzy constrained programming problem.Mon, 30 Sep 2019 20:30:00 +0100(1809-4722) Completeness of Hutton [0; 1]-quasi-uniformities induced by a crisp uniformity
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In [25], Katsaras introduced a method for constructing a Hutton [0, 1]-quasi-uniformity from a crisp uniformity. In thispaper we present other different methods for making this based mainly in the concept of a fuzzy uniform structure.Furthermore, we prove that some of these methods preserve the completeness property of the quasi-uniformity. Moreover,we also show that Katsaras’ construction allows to develop a theory of completion of a Hutton [0,1]-quasi-uniformspace obtained from a uniform space.Fri, 12 Apr 2019 19:30:00 +0100Fuzzy adaptive tracking control for a class of nonlinearly parameterized systems with unknown ...
http://ijfs.usb.ac.ir/article_4909_626.html
This paper addresses the problem of adaptive fuzzy tracking control for aclass of nonlinearly parameterized systems with unknown control directions.In this paper, the nonlinearly parameterized functions are lumped into the unknown continuous functionswhich can be approximated by using the fuzzy logic systems (FLS) in Mamdani type. Then, the Nussbaum-type function is used to detect the unknown control direction and based on the backstepping technique, the adaptive fuzzycontroller is designed. The main advantages of this paper are that (1) in the existing results the separation principle is used to deal with the nonlinearly parameterized functions, unlike them in this paper, the FLS are applied to approximate the nonlinearly parameterized functions, (2) by using the minimal learning parameters (MLP) algorithm, onlyone parameter needs to be adjusted online in the controller design procedure, which reduces the onlinecomputation burden greatly, (3) the Nussbaum-gain technique is introduced to resolve the unknown control direction problems. It is proven that the proposed control scheme renders the closed-loopsystem stable in the sense of semiglobal uniformly ultimately bounded (UUB). Finally, simulation results are provided to show the effectiveness of the proposed approach.Mon, 30 Sep 2019 20:30:00 +0100(1808-4647) On orders induced by implications
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In this paper, the orders induced by the residual implications obtained from uninorms are investigated. A necessaryand sufficient condition is presented so that the ordinal sum of fuzzy implications satisfies the law of importation witha t-norm T. Some relationships between the orders induced by an ordinal sum implication and its summands aredetermined. The algebraic structures obtained from the orders induced by the residual implications and the ordinalsum implications are discussed.Fri, 12 Apr 2019 19:30:00 +0100Mobile robot wall-following control using a behavior-based fuzzy controller in unknown environments
http://ijfs.usb.ac.ir/article_4911_626.html
This paper addresses a behavior-based fuzzy controller (BFC) for mobile robot wall-following control.The wall-following task is usually used to explore an unknown environment.The proposed BFC consists of three sub-fuzzy controllers, including Straight-based Fuzzy Controller (SFC),Left-based Fuzzy Controller (LFC), and Right-based Fuzzy Controller (RFC).The proposed wall-following controller has three characteristics: the mobile robot keeps a distance from the wall,the mobile robot has a high moving velocity, and the mobile robot has a good robustness ability of disturbance.The proposed BFC will be used to control the real mobile robot.The Pioneer 3-DX mobile robot has sonar sensors in front and sides, and it is used in this study.The inputs of BFC are sonar sensors data and the outputs of BFC are robot¡¦s left/right wheel speed.Experimental results show that the proposed BFC successfully performs the mobile robot wall-following taskin a real unknown environment.Mon, 30 Sep 2019 20:30:00 +0100(1804-4407) A new view on fuzzy automata normed linear structure spaces
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In this paper, the concept of fuzzy automata normed linear structure spaces is introduced and suitable examples areprovided. The concepts of fuzzy automata α-open sphere, fuzzy automata N -locally compact spaces, fuzzy automataN -Hausdorff spaces are also discussed. Some properties related with fuzzy automata normed linear structure spacesand fuzzy automata N -Hausdorff spaces are discussed.Fri, 12 Apr 2019 19:30:00 +0100Equality propositional logic and its extensions
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We introduce a new formal logic, called equality propositional logic. It has two basic connectives, $boldsymbol{wedge}$ (conjunction) and $equiv$ (equivalence). Moreover, the $Rightarrow$ (implication) connective can be derived as $ARightarrow B:=(Aboldsymbol{wedge}B)equiv A$. We formulate the equality propositional logic and demonstrate that the resulting logic has reasonable properties such as Modus Ponens(MP) rule, Hypothetical Syllogism(HS) rule and completeness, etc. Especially, we provide two ways to prove the completeness of this logic system. We also introduce two extensions of equality propositional logic. The first one is involutive equality propositional logic, which is equality propositional logic with double negation. The second one adds prelinearity which is rich enough to enjoy the strong completeness property. Finally, we introduce additional connective $Delta$(delta) in equality propositional logic and demonstrate that the resulting logic holds soundness and completeness.Mon, 30 Sep 2019 20:30:00 +0100(1805-4498) A robust aggregation operators for multi-criteria decision-making method with ...
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Molodtsov initiated soft set theory that provided a general mathematical framework for handling with uncertainties inwhich we encounter the data by affix parameterized factor during the information analysis as differentiated to fuzzy aswell as bipolar fuzzy set theory. The main object of this paper is to lay a foundation for providing a new application ofbipolar fuzzy soft tool in considering many problems that contain uncertainties. In present study, aggregation of bipolarfuzzy soft numbers have so far not yet been applied for ranking of alternatives in decision-making problems. To thispropose, bipolar fuzzy soft weighted arithmetic averaging (BFSWAA) operator, bipolar fuzzy soft weighted geometricaveraging (BFSWGA) operator have been used to compare two bipolar fuzzy soft numbers (BFSNs) for aggregatingdifferent bipolar fuzzy soft input arguments in bipolar fuzzy soft environment. Then, their related properties have beeninvestigated. Finally, a practical example for selection of alternatives is given to demonstrate the utility and applicationof the proposed work.Fri, 12 Apr 2019 19:30:00 +0100Monoidal closedness of $L$-generalized convergence spaces
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In this paper, it is shown that the category of stratified $L$-generalized convergence spaces is monoidal closed if the underlying truth-value table $L$ is a complete residuated lattice. In particular, if the underlying truth-value table $L$ is a complete Heyting Algebra, the Cartesian closedness of the category is recaptured by our result.Mon, 30 Sep 2019 20:30:00 +0100(1811-4864) Neuro-fuzzy Control of Bilateral Teleoperation System Using FPGA
http://ijfs.usb.ac.ir/article_4590_0.html
This paper presents an adaptive neuro-fuzzy controller ANFIS (Adaptive neuro-fuzzy inference system) for a bilateralteleoperation system based on FPGA (Field Programmable Gate Array). The proposed controller combines the learningcapabilities of neural networks with the inference capabilities of fuzzy logic, to adapt with dynamic variations in masterand slave robots and to guarantee good practical robustness against the disturbances, by adjusting neuro-fuzzy networkoutput parameters in a short time, thanks to the computing power of FPGA and its high sampling frequency. Thedesign methodology adopted to design the control algorithm aims to minimize the hardware resources used by the FPGAin order to optimize the execution and design times, and this by using the Fixed-Point Tool and HDL Coder featuresof MATLAB-Simulink. The proposed controllers were experimentally validated on a teleoperation system comprisinga pair of one degree of freedom. The experimental results clearly show that the proposed ANFIS control algorithmsignificantly outperformed the conventional control methods (PID).Mon, 15 Apr 2019 19:30:00 +0100Multidimensional fuzzy finite tree automata
http://ijfs.usb.ac.ir/article_4915_626.html
This paper introduces the notion of multidimensional fuzzy finite tree automata (MFFTA) and investigates its closure properties from the area of automata and language theory. MFFTA are a superclass of fuzzy tree automata whose behavior is generalized to adapt to multidimensional fuzzy sets. An MFFTA recognizes a multidimensional fuzzy tree language which is a regular tree language so that for each dimension, a fuzzy membership grade is assigned to each tree. We study MFFTA by extending some classical problems and properties of automata and regular languages such as determinization, reduction, duality and operations on languages. Furthermore, we provided the method of converting every complete fuzzy tree automata to an MFFTA as well as an example to show the efficiency of MFFTA in comparison to FFTA.}Mon, 30 Sep 2019 20:30:00 +0100(1808-4651) The role of states in triangle algebras
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In this paper, we enlarge the language of triangle algebra by adding a unary operation that describes properties of astate. These structure algebras are called state triangle algebra. The vital properties of these algebras are given. Thenotion of state interval-valued residuated lattice (IVRL)-filters are introduced and give some examples and propertiesof them. Using this concept, we define two types IVRL-extended σ-filters of a state triangle algebra.Mon, 15 Apr 2019 19:30:00 +0100An EPQ model for an imperfect production process with fuzzy cycle time and quality screening
http://ijfs.usb.ac.ir/article_4917_626.html
This study has developed a production inventory model where the cycle timeis fuzzy, the existence of defective products is assumed in each batch andproduct screening is performed both in-production and after-production.Triangular fuzzy numbers serve to model uncertainties in the cycle time, anda fuzzified total inventory profit function is created by thedefuzzification method known as the signed distance method. The classicalapproach is used to determine the optimal policy, with the ideal cycle timematched to the total profit. Although assuming asymmetric triangular fuzzynumbers prevents the calculation of a clear analytical solution, the methodapproaches as closely as possible to an analytical solution. A numericalsolution to only one equation is needed to obtain the optimal configuration.Conversely, there is a positive trade-off, with an analytical solution tothe optimization problem if there is an assumption of symmetrical triangularfuzzy numbers. The proposed model is illustrated by a numerical example. Thepaper presents results and sensitivity analyses, in both tables and graphicillustrations. The effects on total profit are discussed in relation tovarious parameters. From the numerical studies, it is observed that thelevel of fuzziness influences the cycle time and an approximately linearrelationship, in the opposite direction, was found between the total profitand the level of fuzziness, when it was increased.Mon, 30 Sep 2019 20:30:00 +0100(1609-3173) Robust Takagi-Sugeno sensor fault tolerant control strategy for nonlinear system
http://ijfs.usb.ac.ir/article_4655_0.html
This paper presents a robust Fault Tolerant Tracking Control (FTTC) design for nonlinear uncertain systems describedby Takagi Sugeno (T-S) fuzzy models with unmeasurable premise variables subject to sensor faults. A ProportionalIntegral Observer (PIO) is proposed to estimate the faulty states and the time-varying sensor faults. The FTTC issynthesized based on the estimation derived from the PIO with a guaranteed H∞ performance to minimize the effect ofthe external disturbance. The trajectory tracking performances and the stability of the closed loop system are analyzedbased on the Lyapunov theory and the L2 optimization. The stability condition are formulated in terms of LinearMatrix Inequality (LMI). The proposed robust FTTC is illustrated using simulation results.Tue, 14 May 2019 19:30:00 +0100Some new variants of interval-valued Gronwall type inequalities on time scales
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By using an efficient partial order and concept of gH-differentiability oninterval-valued functions, we investigate some new variants of Gronwall typeinequalities on time scales, which provide explicit bounds on unknownfunctions. Our results not only unify and extend some continuousinequalities, but also in discrete case, all are new.Mon, 30 Sep 2019 20:30:00 +0100(1702-3514 ) A new method for fuzzification of nested dummy variables by fuzzy clustering ...
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In this study, the aim is to propose a new method for fuzzification of nested dummy variables. The fuzzification idea ofdummy variables has been acquired from non-linear part of regime switching models in econometrics. In these models,the concept of transfer functions is like the notion of fuzzy membership functions, but no principle or linguistic sentencehave been used for inputs. Consequently, for the non-linear part including transfer function, there is no reason why thedifferent types of functions such as logistic are used. Therefore, in order to solve the aforementioned problem like theregime switching models, the transfer functions are considered for dummy variables. However, the presented transferfunctions are proposed by fuzzy clustering membership function. Finally, using fuzzy logic, the membership functionsof clusters are combined with each other and constitute the fuzzy nested regimes. The suggested model has been usedin financial data of Iran’s stock in order to examine the equity premium Puzzle. The results of using above modelhelped in modeling appropriate second-order moments in consumption capital asset pricing model.Tue, 14 May 2019 19:30:00 +0100Persian-translation- 16-5 October 2019
http://ijfs.usb.ac.ir/article_4919_626.html
Mon, 30 Sep 2019 20:30:00 +0100(1805-4474)A new framework for high-technology project evaluation and project portfolio ...
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High-technology projects are known as tools that help achieving productive forces through scientific and technologicalknowledge. These knowledge-based projects are associated with high levels of risks and returns. The process of hightechnologyproject and project portfolio selection has technical complexities and uncertainties. This paper presentsa novel two-parted method of high-technology project portfolio selection. In the rst part, a new decision-makingmodel under Pythagorean fuzzy set (PFS) uncertainty is introduced that is last aggregation and avoids defuzzificationuntil the last step of the process. In the last step, a new PFS ranking method is used to make crisp and comparablevalues. Outcomes from this part form the objective function of a new integer programming (IP) of the project portfolioselection. To display the models application, data from a real case study of high-technology project evaluation andselection is presented, and the steps of the approach are illustrated in addition to presenting the efficacy of the model.Fri, 17 May 2019 19:30:00 +0100(1708-3855) Two-level supply chain for a deteriorating item with stock and promotional cost ...
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In this research work, a wholesaler-retailer-customer supply chain model for a deteriorating item is considered, wherethe retailer's warehouse in the market place has a limited capacity. The retailer can rent an additional warehouse(rented warehouse) if needed, with a higher rent compared to the existing warehouse (own warehouse). The customers'demand of the item is linearly in uenced by the stock level and in case of shortages the base demand is partiallybacklogged. Being the leader of the supply chain, the retailer introduces some promotional cost to boost the basedemand of the item. To participate in joint marketing decision, the wholesaler shares a compromise part of thispromotional cost. Goal of this research work is to maximize the individual profits (when the retailer is the leader andthe wholesaler is the follower) as well as the channel profit (when the retailer and the wholesaler jointly make marketingdecision) of the system. It is established that if the wholesaler shares a part of the promotional cost then the channelprofit as well as the individual prots increase. The supply chain model is also considered in imprecise environmentwhere different inventory parameters are fuzzy/rough in nature. In this case, the individual profits as well as thechannel prot become fuzzy/rough in nature. As optimization of fuzzy/rough objective is not well defined, followingcredibility/trust measure of fuzzy/rough event, an approach is followed for comparison of fuzzy/rough objectives and aParticle Swarm Optimization algorithm is implemented to nd the marketing decisions. Eciency of the algorithm insolving the problem is statistically established. The existence of the joint marketing decision is established analyticallyand numerically (with illustration) in crisp as well as in imprecise environments.Fri, 17 May 2019 19:30:00 +0100(1808-4631) Type-2 fuzzy logic based pitch angle controller for fixed speed wind energy system
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In this paper, an interval Type-2 fuzzy logic based pitch angle controller is proposed for fixed speed wind energy system (WES) to maintain the aerodynamic power at its rated value. The pitch angle reference is generated by the proposed controller which can compensate the non-linear characteristics of the pitch angle to the wind speed. The presence of third dimension in the Type-2 fuzzy logic controller (FLC) membership function offers an additional degree-of-freedom in the design of the Type-2 FLC controller to improve the system performance. The applicability of the proposed controller is evaluated by considering a nonlinear simulation model of the WES which is developed and implemented using OPAL-RT real time digital simulator. The results show that the proposed controller offers better performance than the conventional PI and fuzzy logic controllers.Fri, 17 May 2019 19:30:00 +0100(1806-4554) Adaptive particularly tunable fuzzy particle swarm optimization algorithm
http://ijfs.usb.ac.ir/article_4660_0.html
Particle Swarm Optimization (PSO) is a metaheuristic optimization algorithm that owes much of its allure to its simplicity and its high effectiveness in solving sophisticated optimization problems. However, since the performance of the standard PSO is prone to being trapped in local extrema, abundant variants of PSO have been proposed by far. For instance, Fuzzy Adaptive PSO (FAPSO) algorithms have been being studied extensively in recent years. In this study, a modified version of PSO algorithms is presented and is named as Adaptive Particularly Tunable Fuzzy Particle Swarm Optimization (APT-FPSO). In it, the global and personal learning coefficients of every single particle are tuned adaptively and particularly, at an individual extent, within each iteration with the aid of fuzzy logic concepts. Ample statistical evidence is provided indicating that the proposed algorithm further improves the potentialities and capabilities of the standard PSO.}Fri, 17 May 2019 19:30:00 +0100(1806-4512) A computational method to analyze the similarity of biological sequences under ...
http://ijfs.usb.ac.ir/article_4661_0.html
In this paper, we propose a new method to analyze the difference and similarity of biological sequences, based on the fuzzy set theory. Considering the sequence order and some chemical and structural properties, we present a computational method to cluster the biological sequences. By some examples, we show that the new method is relatively easy and we are able to compare the sequences of arbitrary lengths.Fri, 17 May 2019 19:30:00 +0100(1704-3632) Robustified distance based fuzzy membership function for support vector machine ...
http://ijfs.usb.ac.ir/article_4662_0.html
Fuzzification of support vector machine has been utilized to deal with outlier and noise problem. This importanceis achieved, by the means of fuzzy membership function, which is generally built based on the distance of the pointsto the class centroid. The focus of this research is twofold. Firstly, by taking the advantage of robust statisticsin the fuzzy SVM, more emphasis on reducing the impact of outliers on the generalizability of SVM has been placed.Moreover, the variety of membership function for the elliptical data has been designated, based on the classic and robustMahalanobis distance. Minimum covariance determinant and orthogonalised Gnanadesikan Kettenring estimators areemployed in the structure of the robust–fuzzy SVM. By implementing the new membership function, the disadvantagesof the traditional fuzzy membership function has been rectified. Simulated and real benchmarking data set confirm theeffectiveness of the proposed methods. Compared with the traditional SVM and fuzzy SVM, these methods give a betterperformance on reducing the effects of outliers and significantly improves the classification accuracy and generalization.Sun, 19 May 2019 19:30:00 +0100(1802-4271) Customer loyalty program based on quality function deployment with fuzzy linguistic ...
http://ijfs.usb.ac.ir/article_4793_0.html
The competition among shopping malls is getting increasingly more intense. In order to enhance corporate competitivenessand profitability, how to retain key loyal customers has become an important issue for the managers of shoppingmalls. Customer loyalty programs are a universal practice. This study proposes an analytical model for developing thestrategic management of customer loyalty programs. Based on quality function deployment, our model constructs afuzzy relational matrix to integrate the customer benefits and the customer loyalty programs. The results contributeto a better understanding of the different importance of customer benefits with respect to “Utilitarian benefits”, “Hedonicbenefits” and “Symbolic benefits”. The study’s findings provide prioritized customer loyalty programs, including“Newest information transmissions,” “Communication service specialists,” “Exclusive free gift promotions,” and “VIPlounge service,” which can be used to determine the directions for the improvement for shopping malls. The study hasimplications for the theory and for practitioners. First, it allows for the integration of customer benefits in customerloyalty programs and for the consideration of the VIP customers in the programs. Second, the requirement evaluationconsidering fuzzy linguistic preferences allows for prioritizing the customer loyalty programs when dealing with uncertaintyand vagueness. Finally, this approach helps to obtain more realistic results by integrating fuzzy decision-makinginto QFD.Sun, 30 Jun 2019 19:30:00 +0100(1811-4866) BL-general fuzzy automata and minimal realization: based on the associated categories
http://ijfs.usb.ac.ir/article_4798_0.html
The present paper is an attempt to study the minimal BL-general fuzzy automata which realizes the given fuzzybehavior. Of two methods applied for construction of such automaton presented here, one has been based on Myhill-Nerode's theory while the other has been based on derivatives of the given fuzzy behavior. Meanwhile, the categoriesof BL-general fuzzy automata and fuzzy behavior, along with a functorial relationship between them, are introduced.Tue, 02 Jul 2019 19:30:00 +0100(1810-4784) The Wijsman structure of a quantale-valued metric space
http://ijfs.usb.ac.ir/article_4875_0.html
We define and study a quantale-valued Wijsman structure on the hyperspace of all non-empty closed sets of a quantalevaluedmetric space. We show its admissibility and that the metrical coreflection coincides with the quantale-valuedHausdorff metric and that, for a metric space, the topological coreflection coincides with the classical Wijsman topology.We further define an index of compactness and show that the indices of compactness of the quantale-valued metricspace and of the hyperspaces equipped with the quantale-valued Hausdorff metric and with the quantale-valued Wijsmanstructure coincide.Sun, 01 Sep 2019 19:30:00 +0100( 1901-4968 ) On the Non-Parametric Multivariate Control Charts in Fuzzy Environment
http://ijfs.usb.ac.ir/article_4876_0.html
Multivariate control chats are generally used in situations where the simultaneous monitoring or control of two ormore related quality characteristics is necessary. In most processes in the real world, distribution of the processcharacteristics are unknown or at least Non-normal, so the non-parametric or distribution-free charts are desirable.Most non-parametric statistical process-control techniques depend on ranks. In this survey, we apply the fuzzy settheory to deal with the circumstances that the values of each characteristic are presented in linguistic form, so wepropose non-parametric multivariate control charts based on sign and Wilcoxon signed-rank tests. The performance ofthe proposed charts is investigated in a simulation study. Numerical examples are used to demonstrate the effectivenessand performance of the proposed charts.Sun, 01 Sep 2019 19:30:00 +0100(1807-4598) Switching Fuzzy Modelling and Control Scheme Using T-S Fuzzy Systems with Nonlinear ...
http://ijfs.usb.ac.ir/article_4877_0.html
This paper extends the idea of switching T-S fuzzy systems with linear consequent parts to nonlinear ones. Eachnonlinear subsystem is exactly represented by a T-S fuzzy system with Lure type consequent parts, which allows tomodel and control wider classes of switching systems and also reduce the computation burden of control synthesis.With the use of a switching fuzzy Lyapunov function, the LMI conditions for asymptotic stability of the system withmaximum decay-rate and disturbance attenuation properties under arbitrary switching law are derived. Moreover,several numerical examples are provided to demonstrate the effectiveness of the proposed approaches to reduce thecomputational burden of control synthesis and improving the closed-loop performance of the system.Sun, 01 Sep 2019 19:30:00 +0100(1810-4770) Fuzzy Decision Making in Testing Hypotheses: An Introduction to the Packages ...
http://ijfs.usb.ac.ir/article_4878_0.html
This paper reviews and compares two R packages “FPV” and “Fuzzy.p.value”. These packages are designed fortesting hypotheses in a fuzzy environment using a fuzzy p-value based approach. In fact, the packages “FPV” and“Fuzzy.p.value” propose some useful functions for testing hypotheses when the data / hypotheses are fuzzy rather thancrisp. The proposed methods and functions have been presented together with illustrative practical examples.Sun, 01 Sep 2019 19:30:00 +0100(1810-4773) Partially continuous pretopological and topological operators for intuitionistic ...
http://ijfs.usb.ac.ir/article_4879_0.html
In this paper, pretopological and topological operators are introduced based on partially continuous linear transformationsof the membership and non-membership functions for intuitionistic fuzzy sets. They turn out to be a generalizationof the topological operators for intuitionistic fuzzy sets. On the other hand it is a generalization of the fuzzy set pretopologicaloperators introduced by Wenzhong and Kimfung.Sun, 01 Sep 2019 19:30:00 +0100(1903-5072) Continuity of super- and sub-additive transformations of continuous functions
http://ijfs.usb.ac.ir/article_4880_0.html
We prove a continuity inheritance property for super- and sub-additive transformations of non-negative continuousmultivariate functions defined on the domain of all non-negative points and vanishing at the origin. As a corollaryof this result we obtain that super- and sub-additive transformations of continuous aggregation functions are againcontinuous aggregation functions.Sun, 01 Sep 2019 19:30:00 +0100(1812-4922) Ulam-Hyers-Rassias stability for fuzzy fractional integral equations
http://ijfs.usb.ac.ir/article_4895_0.html
In this paper, we study the fuzzy Ulam-Hyers-Rassias stability for two kinds of fuzzy fractional integral equations byemploying the fixed point technique.Sat, 14 Sep 2019 19:30:00 +0100(1904-5145) Probit and nested logit models based on fuzzy measure
http://ijfs.usb.ac.ir/article_4897_0.html
Inspired by the interactive discrete choice logit models [Aggarwal, 2019], this paper presents the advanced familiesof discrete choice models, such as nested logit, mixed logit, and probit models to consider the interaction amongthe attributes. Besides the DM’s attitudinal character is also taken into consideration in the computation of choiceprobabilities. The proposed choice models make use of Choquet integal and the recent attitudinal Choquet integral.The models are termed as Choquet nested logit (CNL), Choquet mixed multinomial logit (CMMNL), and Choquetmultinomial probit (CMP). These are further extended to represent the DM’s attitudinal character, and termed asattitudinal CNL, attitudinal CMMNL, and attitudinal CMP.Sat, 14 Sep 2019 19:30:00 +0100(1806-4525) Generalized interval-valued intuitionistic fuzzy Hamacher generalized Shapley ...
http://ijfs.usb.ac.ir/article_4920_0.html
The interval-valued intuitionistic fuzzy set (IVIFS) which is an extension of the Atanassov’s intuitionistic fuzzy set is apowerful tool for modeling real life decision making problems. In this paper, we propose the generalized interval-valuedintuitionistic fuzzy Hamacher generalized Shapley Choquet integral (GIVIFHGSCI) and the interval-valued intuitionisticfuzzy Hamacher generalized Shapley Choquet integral (IVIFHGSCI) operators, which consider the importance of theordered positions and correlations among the arguments with the assumption that the aggregated arguments areinterrelated. Furthermore, some of the properties and special cases of these operators are discussed. An approachfor multicriteria decision making based on these operators is developed. Finally an illustrative example follows.Fri, 20 Sep 2019 19:30:00 +0100(1804-4433) Joint influence of leakage delays and proportional delays on almost periodic ...
http://ijfs.usb.ac.ir/article_4921_0.html
This paper deals with fuzzy cellular neural networks (FCNNs) with leakage delays and proportional delays. Applying thedifferential inequality strategy, fixed point theorem and almost periodic function principle, some sufficient criteria whichensure the existence and global attractivity of a unique almost periodic solution for fuzzy cellular neural networks withleakage delays and proportional delays are derived. Computer simulations are carried out to illustrate our theoreticalfindings. Our results are new and complement some previous published ones.Fri, 20 Sep 2019 19:30:00 +0100(1808-4632) A new family of (A, N)-implications: construction and properties
http://ijfs.usb.ac.ir/article_4922_0.html
This paper deals with a new family of (A, N)-implications derived from fuzzy negation and continuous monotonefunction, and, some properties, for instance, the left neutrally, the exchange principle, the ordering property, the lawsof contraposition, for the proposed family of (A, N)-implications are studied. Moreover, the T-conditionality and theModus tollens for the new family of (A, N)-implications are also studied and some results are obtained.Fri, 20 Sep 2019 19:30:00 +0100(1811-4847) Single cycle supply chain coordination model for fuzzy stochastic demand of ...
http://ijfs.usb.ac.ir/article_4923_0.html
Market demand of the perishable bakery products are volatile. Hence, demand of such items are random variable.The most appealing demand distribution of such items is lognormal demand distribution. Using historical data, theparameters of lognormal distribution are obtained. But, there is a problem of overestimation or underestimation of theparameters. Fuzzy triangular numbers are used to overcome such problems. Single period (newsboy) inventory model isused to obtain an optimal order quantity. The retailers and manufacturers profit is obtained by using the supply chaincoordination model. At the end of day, all the remaining items rotted. Hence, there is no gain from unsold items. Also,the some items are defective at the time of purchase. Thus, loss sharing strategy is proposed between manufacturersand retailers. All of these aspects are incorporated in the supply chain coordination model. The data is collected fromKoregaon Park, Pune market, India to illustrate the methodology.Fri, 20 Sep 2019 19:30:00 +0100(1810-4760) A fuzzy capacitated facility location-network design model: A hybrid firefly and ...
http://ijfs.usb.ac.ir/article_4924_0.html
Facility location-network design (FLND) problem, which determines the location of facilities and also communicationlinks between the demand and facility nodes, is arisen from the combination of the facility location and network designproblems. This paper deals with fuzzy capacitated facility location-network design model which aims to select thefacilities and candidate links in a way that yield to minimize the total costs, containing: costs of opening facilities, linkconstruction and transportation costs. In this study, several types of links have been considered for connecting twonodes in which their capacity, transportation and construction costs are distinct. Besides, the possibility of multiplelink selection between two nodes and also the necessity of the existence of a facility in some nodes are considered. Thereare also several types of facilities which the budget for each type is unique. Moreover, to open the facilities and toconstruct the links, limited budgets are considered. As a result of the uncertainty in customers demand, an interactivefuzzy solution approach is applied. Because this problem is classified as an NP-hard class, a hybrid meta-heuristicalgorithm based on Firefly and Invasive Weed Optimization (FIWO) is developed. Finally, the behavior of the modelis tested, and the proposed algorithms performance is compared with some other solving methods.Fri, 20 Sep 2019 19:30:00 +0100(1903-5068) Hyperspace of a fuzzy quasi-uniform space
http://ijfs.usb.ac.ir/article_4925_0.html
The aim of this paper is to present a fuzzy counterpart method of constructing the Hausdorff quasi-uniformity of acrisp quasi-uniformity. This process, based on previous works due to Morsi [25] and Georgescu [9], allows to extendprobabilistic and Hutton [0, 1]-quasi-uniformities on a set X to its power set. In this way, we obtain an endofunctor foreach one of the categories of those objects. We will demonstrate the commutativity of these endofunctors with Lowenand Katsaras’ functors. Furthermore, we will prove the compatibility of our construction with the Hausdorff fuzzyquasi-pseudometric introduced in [33].Fri, 20 Sep 2019 19:30:00 +0100(1807-4565) Interval number ranking method considering multiple decision attitudes
http://ijfs.usb.ac.ir/article_4926_0.html
Many interval number ranking methods cannot represent the different attitudes of decision makers with different riskappetites. Therefore, interval numbers are expressed in the Rectangular Coordinate System (RCS). After mining theinterval numbers in the RCS, the Symmetry Axis Compensation Factor, which is known as λ, was introduced, andthe Equivalent Function of the Goal Interval Number (GIN) was deduced. Thus, the interval number ranking methodconsidering symmetry axis compensation was defined along with its application procedures. Additionally, the feasibilityand effectiveness of this method were veried through examples. This method is intuitive and simple and can representmultiple attitudes of decision makers with different risk appetites.Fri, 20 Sep 2019 19:30:00 +0100(1811-4851) Several new results based on the study of distance measures of intuitionistic fuzzy sets
http://ijfs.usb.ac.ir/article_4927_0.html
It is doubtless that intuitionistic fuzzy set (IFS) theory plays an increasingly important role in solving the problemsunder uncertain situation. As one of the most critical members in the theory, distance measure is widely used inmany aspects. Nevertheless, it is a pity that part of the existing distance measures has some drawbacks in practicalsignificance and accuracy. To make up for their drawbacks and pursue more accuracy and effectiveness, in this paper, wepropose a new inclusion relation of IFSs and a new definition called strict distance measure. Based on this new relation,an analysis is given to point out that the common shortcoming of Hamming distance measure and Euclidean distancemeasure is the mishandling of hesitancy degree. Therefore, the role of hesitancy degree in distance measure is studieddeeply and then three strict distance measures are put forward to overcome the above shortcoming. In addition, a noveldefinition called the characteristic function of distance measure is defined to describe the character of strict distancemeasure. On this basis, a theorem is presented to illustrate the inevitability of the occurrence of unrecognized resultin pattern recognition problems in some special cases. This theorem also shows that the problem cannot be entirelyattributed to distance measures. In view of this condition, we provide an appropriate solution. Compared with otherexisting distance measures in some examples, the superiorities of our improved distance measures are demonstrated tobe more effective and more practical significance.Fri, 20 Sep 2019 19:30:00 +0100(1804-4409) A novel ranking method for intuitionistic fuzzy set based on information fusion and ...
http://ijfs.usb.ac.ir/article_4928_0.html
A novel ranking method based on multi-time information fusion is proposed for intuitionistic fuzzy sets (IFSs) andapplied to the threat assessment problem, a multi-attribute decision making (MADM) one. This method integrates adesigned intuitionistic fuzzy entropy (IFE), the closeness degree of technique for order preference by similarity to idealsolution (TOPSIS), the decision maker¡¯s (DM¡¯s) risk attitude and decision information from DMs in multiple times.Firstly, a novel IFE is designed in order to sufficiently express the fuzziness and the unknown of uncertainty conveyed byIFSs. Secondly, considering the distance from the positive ideal solution and the negative ideal solution simultaneously,the closeness degree of TOPSIS is utilized to characterize the amount of information conveyed by the IFS. The amountof information and the uncertainty of information are combined by the introduction of DMs¡¯ risk attitudes and then; anovel single time ranking method for IFSs is structured. Next, to reflect the subjective ranking intention on alternatives,the comprehensive preference model of DMs is established. The optimal attribute weights are derived from the linearprogramming model which incorporates the subjective ranking intension and the objective ranking result. Finally, thedecision information from DMs in multiple times is aggregated to give the final ranking results. A threat assessmentexample and comparison analysis demonstrates the flexibility and effectiveness of the proposed method.Fri, 20 Sep 2019 19:30:00 +0100(1811-4829) Fuzzy based efficient DBS placement in the 5G cellular network
http://ijfs.usb.ac.ir/article_4930_0.html
Currently, cellular networks are one of the essential communication methods for people. Providing proper coverage forthe users and also offering high-quality services to them are two of the most important issues of concern in cellularnetworks. The fifth-generation cellular communication networks can provide higher data transmission rates, which leadto a higher quality of service but this higher rate has let to reduced antenna coverage in these networks. Besides this,natural and unnatural events in the environment can also affect the coverage of users in the cellular network. One wayto resolve this issue is by using drones as cellular antennas. The most important factor in providing good coverageand high-quality service for users is the optimal placement of antennas. In this article, the problem of finding theappropriate locations of drone base stations (DBSs) is modeled as a P-median optimization problem, where P is thenumber of required antennas to cover the users. We have used a fuzzy clustering algorithm to define a set of specifiedcandidate points that are required to select the locations of DBSs in the P-median model. The optimal value of P wasobtained using the bisection algorithm. Finally, the optimal positions of DBSs have been determined by solving theoptimization problem. According to the results, in the case of a proper selection of fuzzy clustering parameters, betterresults will be obtained in comparison to the results of other approaches.Sat, 21 Sep 2019 20:30:00 +0100(1903-5076) Extended and infinite ordered weighted averaging and sum operators with numerical ...
http://ijfs.usb.ac.ir/article_4931_0.html
This study discusses some variants of Ordered Weighted Averaging (OWA) operators and related information aggregationmethods. In detail, we define the Extended Ordered Weighted Sum (EOWS) operator and the Extended OrderedWeighted Averaging (EOWA) operator, which are applied in scientometrics evaluation where the preference is overfinitely many representative works. As contrast, we also define the Infinite Ordered Weighted Sum (InOWS) operatorand the Infinite Ordered Weighted Averaging (InOWA) operator, which are more suitable for the corresponding scientometrics evaluation where all of works of scholars are considered. We also define the family of Infinite Gaussianmaxitive OWA weights function and the family of Infinite Gaussian OWA weights function, and discuss some of theirmathematical properties. Some illustrative examples, comparisons and figures are provided to better expound theirapplicability in scientometrics evaluation.Sat, 21 Sep 2019 20:30:00 +0100(1812-4906) A new quadratic deviation of fuzzy random variable and its application to portfolio ...
http://ijfs.usb.ac.ir/article_4947_0.html
The aim of this paper is to propose a convex risk measure in the framework of fuzzy random theory and verify itsadvantage over the conventional variance approach. For this purpose, this paper defines the quadratic deviation (QD)of fuzzy random variable as the mathematical expectation of QDs of fuzzy variables. As a result, the new risk criterionessentially describes the variation of a fuzzy random variable around its expected value. For triangular and trapezoidalfuzzy random variables as well as their linear combinations, we establish the analytical expressions of their QDs,and obtain the desirable convexity about the analytical expressions with respect to critical parameters. To explorethe practical value of the proposed QD, we apply it to a portfolio selection problem to quantify the investment risk,and develop three mean-QD models to find the optimal allocation of the fund in different risky securities. Due to theconvexity of our QD, the original three mean-QD models can be turned into their equivalent convex parametric quadraticprogramming problems, which can be solved by conventional optimization methods. The computational results clearlydemonstrate that our new QD signicantly reduces the computational complexity that cannot be avoided when varianceis used as a risk criterion. Finally, the numerical comparison between the proposed mean-QD model and mean-variancemodel is conducted to show the consistency between the optimal results in both techniques. Meanwhile, the comparisonbetween the proposed QD, variance, spread, and second moment is made to summarize the similarities and differencesbetween them, distinguish these four risk criteria and determine their respective application scopes in decision systems.Mon, 30 Sep 2019 20:30:00 +0100(1901-4964) New optimality conditions for multiobjective fuzzy programming problems
http://ijfs.usb.ac.ir/article_4964_0.html
In this paper we study fuzzy multiobjective optimization problems defined for n variables. Based on a new p-dimensionalfuzzy stationary-point definition, necessary efficiency conditions are obtained. And we prove that these conditions arealso sufficient under new fuzzy generalized convexity notions. Furthermore, the results are obtained under generaldifferentiability hypothesis.Tue, 15 Oct 2019 20:30:00 +0100(1902-5015) An extended hesitant group decision-making technique based on the prospect theory ...
http://ijfs.usb.ac.ir/article_4989_0.html
Throughout the present manuscript, we are going to introduce a novel group emergency decision-making technique in which the application of prospect theory explains the psychological behaviour of the decision maker who is affected bythe hesitancy and uncertainty of cognition in decision making problems. Instead of usual aggregation procedure, we implement here a new fusion technique that is based on modified version of extended hesitant fuzzy set (EHFS), and itdefinitely keeps possible amount of expert's information more than the existing fusion technique of hesitant fuzzy set (HFS). The main motivation of re-visiting the concept of EHFS comes from its potential role in increasing the richnessof numerical appearance in the form of value-groups, and of course its ability in identifying various decision makers in decision making situations. Such a definition further expands the practical applications of HFSs. Finally, we employthe barrier lake problem to illustrate the feasibility and the validity of the presented technique.Sun, 03 Nov 2019 20:30:00 +0100(1903-5074) Hesitant q-rung orthopair fuzzy aggregation operators with their applications in ...
http://ijfs.usb.ac.ir/article_4990_0.html
The aim of this manuscript is to present a new concept of hesitant q-rung orthopair fuzzy sets (Hq-ROFSs) by combining the concept of the q-ROFSs as well as Hesitant fuzzy sets. The proposed concept is the generalization of the fuzzysets, intuitionistic fuzzy sets, hesitant fuzzy sets, and Pythagorean fuzzy sets as well as intuitionistic hesitant fuzzy sets (IHFSs) and hesitant Pythagorean fuzzy sets (HPFSs).Furthermore some basic operational laws of hesitant q-rungorthopair fuzzy have been investigated. The score and accuracy functions are defined which play a vital role in decision making process for making comparison between the hesitant q-rung orthopair fuzzy numbers (Hq-ROFNs). Underthe Hq-ROF environment, Hq-ROF weighted averaging (Hq-ROFWA) and Hq-ROF weighted geometric (Hq-ROFWG) operators are introduced and various properties of these aggregation operators are studied. Additionaly, a numericalapplication shows that how the proposed operators are utilized to solve multi-criteria decision making (MCDM) problems in which experts added their optimistic and pessimistic preferences. Finally the analysis of proposed method with othermethods is presented which show that the method presented in this paper is more flexible and superior than existing methods.Sun, 03 Nov 2019 20:30:00 +0100(1902-5024) Using Necessarily Weak Efficient Solutions for Solving a Biobjective Transportation ...
http://ijfs.usb.ac.ir/article_4993_0.html
This paper considers a biobjective transportation problem with various fuzzy objective functions coefficients. Fuzzy coefficients can be of different types such as triangular, trapezoidal, (semi) L - R, or flat (semi) L - R fuzzy numbers.First, we convert the problem to a parametric interval biobjective transportation problem using Υ- cuts of fuzzy coefficients. Then, we consider a fix Υ-cut and obtain a necessarily weak efficient solution to the yielded interval biobjectiveprogram by a new algorithm. It uses basic feasible solutions and the parametric simplex algorithm. Furthermore, we suggest another algorithm for finding a reasonable solution, called Υ-necessarily weak efficient, to the main biobjectivetransportation problem. To illustrate the validity and performance of the proposed algorithms, we present some numerical examples. Sun, 03 Nov 2019 20:30:00 +0100(1811-4823) Trend analysis in L-fuzzy contexts with absent values
http://ijfs.usb.ac.ir/article_4994_0.html
Sometimes we have to work with L-fuzzy context sequences where one or more values are missing. These sequences can represent, among other things, the evolution in time of an L-fuzzy context. The studies of tendencies that wehave done so far used tools that are not valid when the L-fuzzy context has unknown values. In this work we address such situations and we propose new methods to tackle the problem. Besides, we use the study of tendencies to analyserelations between the objects and the attributes of L-fuzzy contexts and to replace the absent values taking into account the behaviour of the sequence.Sun, 03 Nov 2019 20:30:00 +0100(1907-5317)The left (right) distributivity of semi-t-operators over 2-uninorms
http://ijfs.usb.ac.ir/article_4997_0.html
Recently the distributive equations involving various classes of aggregation operators have aroused widespread attentionbecause of their importance in the theoretic and applied communities of fuzzy set theory. 2-uninorms and semi-toperators are two special classes of aggregation operators and have been proved to be useful in many areas such asfuzzy decision making, approximate reasoning and so on. Therefore, the aim of this paper is to investigate the left(right) distributivity of semi-t-operators over 2-uninorms. We consider five subclasses of 2-uninorms and characterizethe corresponding left (right) distributive equations of semi-t-operators over 2-uninorms. Thu, 07 Nov 2019 20:30:00 +0100