Journal of Intelligent & Fuzzy Systems - Volume 32, issue 6

Authors: Ghafour, Karzan | Ramli, Razamin | Zaibidi, Nerda Z.

Article Type: Research Article

Abstract: Queueing models, in which the arrival and/or departure procedure do not follow the Poisson assumption, are more complex and may produce less tractable systematic results. In a production network, each stage or echelon can be portrayed with a lining framework with stock, especially when the procedure is liable to a long sitting tight time for retailers to meet the item. In particular, these problems lead to the uncertainty in demand and lead-time, both of which can be assumed as a probabilistic problem. Therefore, it is vital to create a mechanism to facilitate and reduce the long waiting time in the …system. This paper considers an M/G/6-first come first service queueing model under the continued review (R , Q ) policy. The DMEI-FCFS model is developed to reduce the long expected waiting time of the retailers in the system. The proposed model is able to reduce the expected waiting time in the system from 13 hours and 30 minutes to 6 hours and 2 minutes. From the model, the optimal expected number of the retailers and also the expected waiting time for both the queue and the system can be determined. Finally, the evaluation of the DMEI-FCFS model is conducted based on the performance measures of the expected waiting time in the system and also sensitivity analysis by using a simulation. Show more

Keywords: Poisson arrival rate, Gamma service time, multi service channels and three echelons

DOI: 10.3233/JIFS-152509

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4059-4068, 2017

Authors: Mohagheghi, Vahid | Mousavi, S. Meysam | Vahdani, Behnam | Siadat, Ali

Article Type: Research Article

Abstract: High and new technology-project as a tool to achieve productive forces through scientific and technological knowledge is characterized as knowledge based with high risk and returns. Often conflicting objectives of these projects have complicated their assessment and selection process. This paper offers a novel approach of high technology-project portfolio selection in two main parts. In the first part, a new risk reduction compromise decision-making model is proposed that applies a new approach in determining the weights of experts and in avoiding information loss. The objective function of a new interval type-2 fuzzy sets (IT2Fs) based mathematical model of project portfolio …selection is formed by the outcome. To depict model’s applicability, data from case study of high technology-project selection in the literature is used to present the efficacy of the model. Show more

Keywords: High and new technology-projects, project portfolio selection, compromise solutions, mathematical modeling, interval type-2 fuzzy sets

DOI: 10.3233/JIFS-152510

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4069-4079, 2017

Authors: Ebrahimnejad, S. | Naeini, M.A. | Gitinavard, H. | Mousavi, S.M.

Article Type: Research Article

Abstract: In current global business, outsourcing of information technology (IT) has become a growing approach. In this respect, selecting a service activity of IT outsourcing as well as IT outsourcing projects could be designed based on multi-criteria decision-making frameworks. This study proposes a new decision-making approach based on group decision analysis under interval-valued hesitant fuzzy (IVHF)-environment to rank the IT outsourcing services’ activities. The IVHFSs could assist the decision makers by assigning some interval-values membership degrees for an IT outsourcing services’ activities among the conflict criteria under a set to margin of errors. For this purpose, the preferences and opinions of …decision makers are expressed by linguistic terms, which are converted to interval-valued hesitant fuzzy elements. In the proposed approach, the weights of criteria and decision makers are computed based on interval-valued hesitant fuzzy preference evaluation method and interval-valued hesitant fuzzy utility degree method, respectively. Consequently, the criteria and decision makers’ weights are provided in the procedure of proposed evaluating and ranking approach to decrease the errors. In addition, the decision makers’ judgments are aggregated in the last step of the proposed approach to avoid the loss of data. Finally, the proposed interval-valued hesitant fuzzy approach is implemented to a real case study to indicate the applicability of the presented approach. In addition, a comparative analysis is provided to discuss the obtained results. Show more

Keywords: IT outsourcing, group decision making model, interval-valued hesitant fuzzy sets theory, IT services providers

DOI: 10.3233/JIFS-152520

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4081-4093, 2017

Authors: Abiri, Ebrahim | Bezareh, Zobeideh | Darabi, Abdolreza

Article Type: Research Article

Abstract: The memory includes flip flap cells which can store binary information. Therefore by designing the binary storing cell, which has the low chip area and power consumption, the high capacity memories with high performance can be presented. The gate diffusion input (GDI) method employed in designing low power logic gates can decrease the chip area and parasitic and interconnection capacitors. In this paper, the modified-GDI (m-GDI) method is used based on a basic GDI method in order to design master-slave D-Flip Flap (M/S-DFF) circuit. By employing the presented M/S-DFF circuit and the Boolean functions of m-GDI method, Random Access Memory …(RAM) cell is designed. For optimizing the performance of the proposed memory cell and gaining the minimum power and propagation delay, the transistors size is adjusted with non-dominated sorting genetic algorithm-II (NSGA-II) in MATLAB software. Finally, the 4-words×4-bits RAM (4×4 RAM) cell is designed and evaluated by employing optimized RAM cell with algorithm. Due to the achieved results, the power consumption of the 4×4 RAM cell is 72.3% , while its propagation delay and Power-Delay Product (PDP) criterion are decreased 75.9% and 93% , respectively, in compare with similar cells which aren’t optimized. The circuit simulation is done with Synopsys H-SPICE simulator in 32 nm CNTFET technology. For ensuring the accurate function of this algorithm, it is experimented on memory cell and decoder. By comparing NSGA-II algorithm with Multiple Objective Particle Swarm Optimization (MOPSO) algorithm, it can be observed that this method has good ability in multi-objective optimization. Show more

Keywords: Gate Diffusion Input (GDI) method, carbon nano tube (CNT) field effect transistor (CNTFET), Non-dominated Sorting Genetic Algorithm II (NSGA- II), Random Access Memory (RAM), Power-Delay Product (PDP), multiple objective particle swarm optimization (MOPSO)

DOI: 10.3233/JIFS-152591

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4095-4108, 2017

Authors: Gao, Xiao-Yan | Yang, Xiao-Fei

Article Type: Research Article

Abstract: In this paper, the concept of compactness measures of (L , M )-fuzzy Q-convergence spaces is introduced. It is used to define compactness measures of (L , M )-fuzzy topological spaces and pointwise (L , M )-fuzzy quasi-uniform spaces. It is shown that the concept of compactness measures satisfies the lattice-valued Tychonoff theorem in the framework of (L , M )-fuzzy Q-convergence spaces and (L , M )-fuzzy topological spaces. Also, it is proved that the compactness measures of a pointwise (L , M )-fuzzy quasi-uniform space is equal to the compactness measures of its induced (L , M )-fuzzy …topological space. Show more

Keywords: Compactness, (L, M)-fuzzy Q-convergence space, (L, M)-fuzzy topology, Pointwise (L, M)-fuzzy quasi-uniformity

DOI: 10.3233/JIFS-152603

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4109-4118, 2017

Authors: Naz, Shafaq | Shabir, Muhammad

Article Type: Research Article

Abstract: This paper deals with a particular class of hyperstructures called semihypergroups, which is a generalization of semigroups. We introduce the notions of SU-qausi hyperideal, SU-bi-hyperideal, SU-generalized bi-hyperideal, SU-interior hyperideal and discuss several properties of these hyperideals. We also characterize regular and intra-regular semihypergroups by the properties of their SU-hyperideals.

Keywords: SU-subsemihypergroup, SU-quasi-hyperideal, SU-bi-hyperideal, SU-generalizedbi-hyperideal, SU-interior hyperideal, regular semihypergroup and intra-regular semihypergroup

DOI: 10.3233/JIFS-15331

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4119-4134, 2017

Authors: Jiang, Qi-yu | Yang, Xiao-jing | Sun, Xiao-sheng

Article Type: Research Article

Abstract: Sub-health is the third state featuring a deterioration in physiological function between health and illness, and it has been a global problem received increasing attention. This paper presents a novel computational model for aided diagnosis of sub-health, which is with TCM (Traditional Chinese Medicine) diagnosis as an instance. All the original medical records of sub-health were obtained from the First Affiliated Hospital of Guangzhou University of Chinese Medicine, and these records were divided into training set (training cases) and test set (test cases). Based on rough set and fuzzy mathematics, training set was used to extract important features in different …classifications of sub-health and generated fuzzy weight matrixes. The results of test set were achieved with integrated calculation of fuzzy weight matrixes and feature values of sub-health symptom. In order to further evaluate the novel model, it was compared with the linear model, Naive Bayesian classification and fuzzy comprehensive. The results showed that the accuracy of the novel model for the diagnosis of sub-health is higher than the linear model and Naive Bayesian classification, and is a little better than fuzzy comprehensive. So the novel model presented in this study can be used to assist the diagnosis of sub-health and play an active role in intelligent medical inthe future. Show more

Keywords: Aided decision, diagnosis model, fuzzy mathematics, rough set, TCM

DOI: 10.3233/JIFS-15958

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4135-4143, 2017

Authors: Tong, Qiang | Cheng, Jingwei | Zhang, Fu

Article Type: Research Article

Abstract: In recent years there have been a great deal of interests in effectively extracting information from RDF repositories. However, users often experience empty answer problems (EAP) when they are not familiar with the structure or content of a RDF dataset and issue a restrictive query to the system. A solution is to allow users to incorporate fuzzy conditions into the query to make it more flexible. Although a fuzzy query is more or less satisfactory, there are still occasions when no or too few entities in a RDF dataset satisfy the query criteria with a degree more than zero, which …is called a fuzzy-EAP problem. In this paper, we propose a query relaxation approach based on relative proximity relations to tackle this problem. We present a framework of fuzzy query relaxation over RDF datasets, and present query relaxation algorithms for atomic f-SPARQL queries and complex f-SPARQL queries. Moreover, this paper reports on a prototype implementation on an extension of LUBM dataset to verify the feasibility and effectiveness of the proposed method. The experimental results show a relatively high recall as more relevant results are returned after relaxation. Show more

Keywords: Query relaxation, f-SPARQL, flexible RDF queries, relative proximity relation, minimal failing subqueries

DOI: 10.3233/JIFS-16675

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4145-4157, 2017

Authors: Rocha Filho, Orlando Donato | de Oliveira, Ginalber Luiz Serra

Article Type: Research Article

Abstract: In this paper an evolving Neuro–Fuzzy Network Modeling based on recursive parameter estimation with fuzzy instrumental variable method, is proposed. The proposed methodology presents an online evolving clustering algorithm composed of participatory learning based on the maximum likelihood norm. To avoid the curse of dimensionality in relation to the number of evolving rules, the algorithm uses an online adaptive norm strategy in the creation of fuzzy rules. The performance of the proposed methodology is concerned to benchmark problems: experiments considering the convergence analysis, by proposal of three Lemmas and one Theorem, of the fuzzy instrumental variable applied to the parametric …estimation of nonlinear systems in a noise environment; nonlinear systems identification are performed and compared to evaluate the performance of the approach proposed with other models of evolving systems widely cited in the literature and statistical analysis of experimental results from black box modeling of a helicopter with two degrees of freedom are used for the purpose of show the performance and efficiency the proposed approach. Show more

Keywords: Evolving Neuro–Fuzzy, Takagi–Sugeno, black box modeling fuzzy instrumental variable

DOI: 10.3233/JIFS-16569

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4159-4172, 2017

Authors: Bagheri, Mansour | Miri, Mahmoud | Shabakhty, Naser

Article Type: Research Article

Abstract: In this paper modeling of epistemic uncertainty in reliability analysis of structures under degradation of resistance has been brought into focus. Proposing a new method, random variables has been modeled in the form of fuzzy triangular numbers and applying alpha level set optimization method based on genetic algorithm and FORM method, the fuzzy time dependent reliability index of a steel corroded beam has been determined. The proposed method is operative in the problems in which most of random variables are fuzzy sets and in nonlinear limit state functions. The fuzzy time dependent reliability index including bounds of uncertainty, offers a …more comprehensive evaluation of reliability of structures compared to classic methods of time dependent reliability analysis. Survey results showed the accuracy and efficiently of the proposed method in comparison to the alternative search approaches thorough lower computational effort. Show more

Keywords: Fuzzy random variable (FRV), alpha level set optimization method, Genetic Algorithm (GA), first order reliability method (FORM), corrosion

DOI: 10.3233/JIFS-161320

Citation: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 6, pp. 4173-4182, 2017