Journal of Intelligent & Fuzzy Systems - Volume 37, issue 6

Authors: Li, Yongkun | Wang, Chun

Article Type: Research Article

Abstract:  In this paper, we consider a class of quaternion-valued inertial neural networks with time-varying delays. First, by applying a continuation theorem of coincidence degree theory, we establish the existence of anti-periodic solutions of the considered neural networks. Second, by choosing a proper variable substitution, we transform the neural networks into a system of first order differential equations, and by constructing a suitable Lyapunov function, we derive a set of sufficient conditions ensuring the global exponential stability of the system. Finally, we give two examples to illustrate the effectiveness of our results.

Keywords: Quaternion-valued inertial neural networks, anti-periodic solutions, coincidence degree, exponential stability

DOI: 10.3233/JIFS-182731

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7797-7813, 2019

Authors: Shoaib, Muhammad | Cheong, Joono | Kim, Younghwan | Cho, Hyeonjoong

Article Type: Research Article

Abstract: We present a novel technique for 3D point cloud simplification — the so-called fractal bubble algorithm — to minimize the computational time and overall storage space. The proposed fractal bubble algorithm generates 2D elastic bubbles and copies of themselves through 2D data sets representing planar geometric contours. Each of the bubbles, as it grows, is made to select a single point of its first contact, and all the selected points become the simplified set of points. The fractal bubble algorithm is repeatedly applied to the simplification of planar slices of general 3D point clouds corresponding to 3D geometric objects, leading …to the global simplification of 3D point clouds. The benefits of the algorithm are: first the algorithm is computationally light and memory efficient, second it is simple to implement and inherently allows the organized selection of the points of contact and finally it enables us to simplify the point cloud data through a multi-scale fashion by varying a set of user-controlled algorithm parameters. Numerical results verify the effectiveness of the proposed algorithm. Show more

Keywords: 3D point cloud, fractal bubble algorithm, data simplification, multi-scale reduction

DOI: 10.3233/JIFS-182742

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7815-7830, 2019

Authors: Dey, Arindam | Agarwal, Aayush | Dixit, Pranav | Long, Hoang Viet | Werner, Frank | Pal, Tandra | Son, Le Hoang

Article Type: Research Article

Abstract: A genetic algorithm (GA) belongs to the class of evolutionary algorithms and it is one of the most studied heuristic algorithms to solve graph coloring problems. In this paper, we propose a new GA algorithm for the total graph coloring problem. To the best of our knowledge, no algorithm based on a GA exists in the literature for total graph coloring. In the proposed approach, a novel encoding scheme is introduced, where all the edges and vertices of the graph are represented in a chromosome without any repetition. For the initialization of the population, a greedy algorithm is used to …determine the total number of colors required for a total coloring of the graph. The number of colors is used as the fitness value of a chromosome which depends on the sequence of vertices and edges representing the chromosome. We introduce a convergence criteria for GA based on the total coloring conjecture. A two-point crossover and mutation operations, suitable for total coloring, are suggested. The proposed algorithm is applied on some well-known and standard graphs. In our computational tests, graphs are used with a maximum number of 690 vertices and 6650 edges of the graph, respectively. The proposed algorithm determines an optimal solution for 21 graphs among the 27 graphs. The solution of remaining the 6 graphs is near optimal and differs by at most one unit from the optimal value. The results show the effectiveness of the proposed approach. Show more

Keywords: Total coloring, total chromatic number, total coloring conjecture, genetic algorithm, crossover, mutation

DOI: 10.3233/JIFS-182816

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7831-7838, 2019

Authors: Aslam, Muhammad | Raza, Muhammad Ali | Ahmad, Liaquat

Article Type: Research Article

Abstract: In this paper, a new acceptance-sampling plan has been introduced for the two-stage process for multiple lines under the neutrosophic statistics. The parameters of the proposed sampling plan have been determined by satisfying the given risks using the optimization solution under the neutrosophic statistical interval method (NSIM) Using the specific producer’s and consumer’s risks, the parameters of the proposed plan have also been determined under neutrosophic operating function (NOF). The comparison based on the sample size of the proposed and the existing plans has been given at different plan parameters. The tables are provided, and an industrial example is illustrated …for the practical use of the proposed sampling plan. The comparison reveals that the proposed plan is more efficient, flexible, and adequate to be used under uncertainty. Show more

Keywords: Neutrosophic statistic, EWMA, sampling plan, producer’s and consumer’s risks, multistage neutrosophic, average sample number

DOI: 10.3233/JIFS-182849

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7839-7850, 2019

Authors: Mahesh, Miriyala | Harigovindan, V.P.

Article Type: Research Article

Abstract:  IEEE 802.11ah defines amendments to IEEE 802.11 to support the Internet of Things (IoT). IEEE 802.11ah implements restricted access window (RAW) mechanism to reduce the contention and energy consumption in dense IoT networks. The RAW mechanism is a group-based MAC protocol that partitions the devices into various groups and confines the channel access of a group of devices to the restricted time interval known as the RAW slot. However, the standard does not specify, grouping mechanism, duration of RAW slots, and the number of RAW slots while configuring the RAW mechanism. In an IoT network, each device has distinct transmission …requirements. Thus, it is necessary to find the optimal number of RAW slots that can maximize the network performance, to group the devices with similar transmission requirements and to assign a RAW slot that adaptively varies with the traffic requirements of the respective group. In this paper, we exploit fuzzy logic to find the optimal number of RAW slots by considering network size, collision probability, and modulation and coding schemes. Further, we propose a traffic-aware adaptive RAW slot allocation (TARA) scheme that uses fuzzy c-means clustering algorithm to group the devices with similar traffic requirements and to assign each group with a RAW slot whose duration adaptively varies with the transmission requirements of the devices. We have also presented a simple yet accurate analytical model to evaluate the performance of the RAW mechanism. Results show that the optimal number of RAW slots found using fuzzy logic significantly enhances the performance of the RAW mechanism in terms of throughput and energy consumption. Further, it is observed that the TARA scheme can effectively meet the traffic requirements of different group of devices when compared to the uniform grouping scheme. Finally, extensive simulations are conducted using ns-3 to validate the analytical results. Show more

Keywords: Internet of Things (IoT), restricted access window (RAW), IEEE 802.11ah, fuzzy logic, Wi-Fi HaLow, fuzzy c-means clustering

DOI: 10.3233/JIFS-182899

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7851-7864, 2019

Authors: Eslami, Mohammad | Shayesteh, Mohammad Reza | Pourahmadi, Majid | Ayatollahitafti, Vahid

Article Type: Research Article

Abstract: Generally, increase in energy demand and consequently unwanted events in a current system will lead to instability. To increase the power system reliability, the current system can be expanded, resulting in a high financial burden. Therefore, one of the most effective options is appropriate controllers usage for stability. In order to overcome the defects of classical controllers such as non-linear, complex uncertain systems, an appropriate mathematical model needs to be designed in limited working conditions. In this paper, a new fractional-order fuzzy proportional-integral-deferential (FOPID) controller is proposed. The proposed controller in its structure is an integral, derivative gain with a …fractional order. This controller is structurally adjustable with two fractional orders, performing the stability process in a short time. On the other hand, in the proposed controller, the optimal adjustment of the controller gain and membership functions has turned into an optimization problem, which is done by a hybrid algorithm based on the virus colony search (VCS) and artificial bee colony (ABC). Local and final search powers in the proposed hybrid algorithm reduce the possibility of local presence dramatically. Simulation results have shown that the proposed controller achieves the higher robustness, the lower fall time, and the lower frequency oscillations compared to the existing controllers. Show more

Keywords: Fractional-order fuzzy controller, intelligent hybrid algorithm, virus serach colony, bee colony, optimization, low frequency oscillation

DOI: 10.3233/JIFS-182918

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7865-7882, 2019

Authors: Sirbiladze, Gia | Ghvaberidze, Bezhan | Matsaberidze, Bidzina | Midodashvili, Bidzina

Article Type: Research Article

Abstract: For the facility location problem under extreme environment a two-stage fuzzy approach is developed. On the first stage, the fuzzy multi-attribute group decision making (MAGDM) model for evaluation of the selection ranking index of a candidate service site is created. For this purpose the triangular fuzzy Choquet averaging (TFCA) operator is constructed. Interaction attributes, influencing the service centers’ selection process, are defined. Interaction indexes between attributes and importance values of attributes are taken into account in the construction of the 2-order additive triangular fuzzy valued fuzzy measure (TFVFM). On the second stage, based on the TFCA operator, a new objective …function - selection ranking index of candidate sites is constructed. We consider also two classical objective functions - total cost for opening of service centers and number of agents needed to operate the opened service centers. A new objective function together with latter ones creates the multi-objective fuzzy facility location set covering problem. A Pareto front for this problem is constructed. A simulation example of emergency service facility location planning for a city is considered. The example deals with the problem of planning fire station locations for serving emergency situations in specific demand points – critical infrastructure objects. Show more

Keywords: Multi-objective facility location problem, associated probabilities of a fuzzy measure, fuzzy numbers, choquet integral, multi-attribute group decision making

DOI: 10.3233/JIFS-18723

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7883-7893, 2019

Authors: Yang, Eunsuk

Article Type: Research Article

Abstract:  This paper investigates standard completeness for substructural fuzzy logics based on mianorms with n -contraction and n -mingle axioms. For this, first, right and left n -contractive and n -mingle logic systems based on mianorms , their corresponding algebraic structures, and their algebraic completeness results are discussed. Next, completeness with respect to algebras whose lattice reduct is [0, 1], known as standard completeness , is established for these systems via Yang’s construction in the style of Jenei–Montagna. Finally, further standard completeness results are introduced for their fixpointed involutive extensions.

Keywords: Mianorms, substructural logic, fuzzy logic, semilinear logic, mianorm-based logic

DOI: 10.3233/JIFS-190150

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7895-7907, 2019

Authors: Deng, Xue | Liu, Guandong

Article Type: Research Article

Abstract: Considering the uncertainty of financial market and the investor’s different attitudes towards risk caused by the various goals, in this paper, a portfolio selection problem with background risks and mental accounts constraints is studied to explore their impact on investment decisions. Firstly, we establish a model with normal uncertain variables, and the optimal solutions of portfolio models with and without background risk are compared. Secondly, considering that the investors always divide an account into several sub-accounts, we put forward an uncertain portfolio model combining uncertainty theory and mental account theory. Thirdly, a portfolio model with background risk and mental accounts …is proposed, and the total expected returns of the models in with different proportions of mental accounts are compared. Finally, some numerical applications are provided to validate the model. The result shows that when the levels of tolerance are the same, the expected return of a portfolio with background risk is lower than that without background risk. In addition, the result also shows that when the percent of savings account decreases and that of the consumption account increases, the total expected return increases. Show more

Keywords: Uncertain theory, portfolio selection, background risk, mental account, saving account

DOI: 10.3233/JIFS-190157

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7909-7921, 2019

Authors: Pereira, Javier | de Oliveira, Elaine C.B. | Morais, Danielle C. | Costa, Ana Paula C.S. | Arroyo-López, Pilar

Article Type: Research Article

Abstract: ELECTRE TRI, a family of multi-criteria methods used to sort alternatives into preference-ordered categories, defines an outranking function to measure the membership degree of an alternative to a category, whenever imprecise evaluations are available. Recent extensions use Hesitant Fuzzy Sets (HFS) to consider uncertain evaluations. However, deterministic parameters are considered, which avoids the application to cases in which non-fuzzy scores and unstable parameters are available. In this study, an approach is proposed for: 1) modeling hesitant outranking functions originated from unstable parameters provided by several DMs; 2) using the HFS to calculate the ELECTRE TRI-C indices; 3) reducing the DMs …cognitive effort when they are asked to provide information. An application to supplier development is presented by using ELECTRE TRI-C. Results are compared by using different HFS aggregation operators and sensitivity analysis shows that a robust conclusion can be obtained. Future lines of research are also suggested. Show more

Keywords: ELECTRE TRI-C, hesitant fuzzy sets, sensitivity analysis, supplier development

DOI: 10.3233/JIFS-190166

Citation: Journal of Intelligent & Fuzzy Systems, vol. 37, no. 6, pp. 7923-7933, 2019