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1.
Computing with words applications are mostly built using rule‐based systems, which have some important deficits: First, it is not easy to deal with high dimension problems because the size of the rule base increases exponentially; second, it is not possible to concatenate two or more systems without losing information; and third, there are no ways to compute inputs from outputs. In this article we show an alternative kind of system that remedies those deficits in many applications. It is based on fuzzy arithmetic rather than fuzzy logic. We also show application examples. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 121–142, 2006.  相似文献   

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This work presents a novel computer‐aided design (CAD) tool for the design of tapered leaky‐wave antennas (LWAs) in hybrid waveguide printed‐circuit technology. The software package is composed of several tools, which are connected together to provide a semi‐automated step‐by‐step design procedure. The design procedure is presented and the different tools are described, together with the involved theory, leading to the design of tapered LWAs. A practical taper design is performed, and comparisons with simulations using commercial software (HFSS) are presented for validation purposes. Due to the full‐wave nature of the technique used in the analysis engine, excellent agreement is shown between the proposed 2D‐based approach, and 3D HFSS results. Also, the analysis procedure is fast, thus leading to semi‐automated designs that are not affordable with common 3D optimization techniques. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2006.  相似文献   

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A novel dispersion formulation of the 2D alternating‐direction implicit (ADI) finite‐difference time‐domain (FDTD) method is presented. The formulation is based on an increasing process analysis of the monochromatic wave in free space. A numerical experiment scheme is designed to verify the accuracy of the proposed formulation. The results obtained from the proposed formulation are in a good agreement with those from the numerical experiments, and the proposed formulation is more accurate than those reported in the literature. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2006.  相似文献   

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An effective foreign exchange (forex) trading decision is usually dependent on effective forex forecasting. In this study, an intelligent system framework integrating forex forecasting and trading decision is first proposed. Based on this framework, an advanced intelligent decision support system (DSS) incorporating a back‐propagation neural network (BPNN)‐based forex forecasting subsystem and Web‐based forex trading decision support subsystem is developed, which has been used to predict the directional change of daily forex rates and provide intelligent online decision support for financial institutions and individual investors. This article describes the forex forecasting and trading decision method, the system architecture, main functions, and operation of the developed DSS system. A comparative study is conducted between our developed system and others commonly used in order to assess the overall performance of the developed system. The assessment results show that our developed DSS outperforms some commonly used forex forecasting and trading decision systems and can provide intelligent e‐service for forex traders to make useful trading decisions in the forex market. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 475–499, 2007.  相似文献   

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The intelligent Fril/SQL interrogator is an object‐oriented and knowledge‐based support query system, which is implemented by the set of logic objects linking one another. These logic objects integrate SQL query, support logic programming language—Fril and Fril query together by processing them in sequence in slots of each logic object. This approach therefore takes advantage of both object‐oriented system and a logic programming‐based system. Fuzzy logic data mining and a machine learning tool kit built in the intelligent interrogator can automatically provide a knowledge base or rules to assist a human to analyze huge data sets or create intelligent controllers. Alternatively, users can write or edit the knowledge base or rules according to their requirements, so that the intelligent interrogator is also a support logic programming environment where users can write and run various Fril programs through these logic objects. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 279–302, 2007.  相似文献   

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In current practice, broccoli heads are selectively harvested by hand. The goal of our work is to develop a robot that can selectively harvest broccoli heads, thereby reducing labor costs. An essential element of such a robot is an image‐processing algorithm that can detect broccoli heads. In this study, we developed a deep learning algorithm for this purpose, using the Mask Region‐based Convolutional Neural Network. To be applied on a robot, the algorithm must detect broccoli heads from any cultivar, meaning that it can generalize on the broccoli images. We hypothesized that our algorithm can be generalized through network simplification and data augmentation. We found that network simplification decreased the generalization performance, whereas data augmentation increased the generalization performance. In data augmentation, the geometric transformations (rotation, cropping, and scaling) led to a better image generalization than the photometric transformations (light, color, and texture). Furthermore, the algorithm was generalized on a broccoli cultivar when 5% of the training images were images of that cultivar. Our algorithm detected 229 of the 232 harvestable broccoli heads from three cultivars. We also tested our algorithm on an online broccoli data set, which our algorithm was not previously trained on. On this data set, our algorithm detected 175 of the 176 harvestable broccoli heads, proving that the algorithm was successfully generalized. Finally, we performed a cost‐benefit analysis for a robot equipped with our algorithm. We concluded that the robot was more profitable than the human harvest and that our algorithm provided a sufficient basis for robot commercialization.  相似文献   

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The circuit envelope (CE) simulation technique is reviewed for the first time in this article. The concomitant models of linear devices applied in the CE simulation are discussed. Then, a method to obtain the responses of the nonlinear circuits excited by multicarrier modulated signals is developed. A novel decimal‐coding chaos genetic algorithm (DCGA) combined with the suitable crossover and mutation operations is firstly presented for solving the nonlinear equations encountered in the CE simulation. The chaos process is applied to find further ascendant solutions in the current genus space in order to update the current colony and avoid premature states in the whole evolution progress. Finally, some examples are studied to verify the validity of the DCGA. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2006  相似文献   

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The major contribution of fuzzy set theory is its capability of representing vague data. Fuzzy logic offers a systematic base in dealing with situations that are ambiguous or not well defined. In the literature, there exist some fuzzy control charts developed for linguistic data that are mainly based on membership and probabilistic approaches. In this article, α‐cut control charts for attributes are developed. This approach provides the ability of determining the tightness of the inspection by selecting a suitable α‐level: The higher α the tighter inspection. The article also presents a numerical example and interprets and compares other results with the approaches developed previously. © 2004 Wiley Periodicals, Inc. Int J Int Syst 19: 1173–1195, 2004.  相似文献   

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In this article, a stochastic search technique based on seeker optimization algorithm (SOA) is proposed for null steering of linear antenna arrays by controlling the position‐only, phase‐only, and amplitude‐only. The SOA is relatively new optimization algorithm based on the concept of simulating the act of humans' intelligent search with their memory, experience, and uncertainty reasoning. Several numerical examples of Chebyshev pattern with the single, multiple, and broad nulls imposed at the directions of interference are given to illustrate the performance and flexibility of the proposed algorithm. For a comparison, the nulling patterns obtained by simulated annealing (SA) and tabu search (TS) algorithms are also given. Furthermore, the results of SOA are statistically compared with those of SA and TS algorithms. The statistical results of simulations show that SOA is superior to the other compared algorithms. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   

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Yang Xu  Da Ruan 《Information Sciences》2011,181(10):1836-1862
Key issues for resolution-based automated reasoning in lattice-valued first-order logic LF(X) are investigated with truth-values in a lattice-valued logical algebraic structure-lattice implication algebra (LIA). The determination of resolution at a certain truth-value level (called α-resolution) in LF(X) is proved to be equivalently transformed into the determination of α-resolution in lattice-valued propositional logic LP(X) based on LIA. The determination of α-resolution of any quasi-regular generalized literals and constants under various cases in LP(X) is further analyzed, specified, and subsequently verified. Hence the determination of α-resolution in LF(X) can be accordingly solved to a very broad extent, which not only lays a foundation for the practical implementation of automated reasoning algorithms in LF(X), but also provides a key support for α-resolution-based automated reasoning approaches and algorithms in LIA based linguistic truth-valued logics.  相似文献   

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Traditional connectionist theory-refinement systems map the dependencies of a domain-specific rule base into a neural network, and then refine this network using neural learning techniques. Most of these systems, however, lack the ability to refine their network's topology and are thus unable to add new rules to the (reformulated) rule base. Therefore, with domain theories that lack rules, generalization is poor, and training can corrupt the original rules — even those that were initially correct. The paper presents TopGen, an extension to the KBANN algorithm, which heuristically searches for possible expansions to the KBANN network. TopGen does this by dynamically adding hidden nodes to the neural representation of the domain theory, in a manner that is analogous to the adding of rules and conjuncts to the symbolic rule base. Experiments indicate that the method is able to heuristically find effective places to add nodes to the knowledge bases of four real-world problems, as well as an artificial chess domain. The experiments also verify that new nodes must be added in an intelligent manner. The algorithm showed statistically significant improvements over the KBANN algorithm in all five domains.  相似文献   

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This article introduces a self‐organizing map‐based approach for estimating the climatic profile of locations of interest situated within an area of known morphology. The potential of the proposed methodology is illustrated on a number of locations within the Greek territory, and its superiority over other—customarily used as well as novel—climatic profile estimation methodologies is demonstrated and numerically evaluated. It is envisioned that, after further development, the proposed methodology can be employed for creating accurate climatic maps of areas of known morphology. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 503–522, 2006.  相似文献   

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We propose an algorithm to quadrangulate an N‐sided patch (2 ≤ N ≤ 6) with prescribed numbers of edge subdivisions at its boundary. Our algorithm is guaranteed to succeed for arbitrary valid input, which is proved using a canonical simplification of the input and a small set of topological patterns that are sufficient for supporting all possible cases. Our algorithm produces solutions with minimal number of irregular vertices by default, but it also allows the user to choose other feasible solutions by solving a set of small integer linear programs. We demonstrate the effectiveness of our algorithm by integrating it into a sketch‐based quad remeshing system. A reference C++ implementation of our algorithm is provided as a supplementary material.  相似文献   

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This paper develops a kinematic path‐tracking algorithm for a nonholonomic mobile robot using an iterative learning control (ILC) technique. The proposed algorithm produces a robot velocity command, which is to be executed by the proper dynamic controller of the robot. The difference between the velocity command and the actual velocity acts as state disturbances in the kinematic model of the mobile robot. Given the kinematic model with state disturbances, we present an ILC‐based path‐tracking algorithm. An iterative learning rule with both predictive and current learning terms is used to overcome uncertainties and the disturbances in the system. It shows that the system states, outputs, and control inputs are guaranteed to converge to the desired trajectories with or without state disturbances, output disturbances, or initial state errors. Simulations and experiments using an actual mobile robot verify the feasibility and validity of the proposed learning algorithm. © 2005 Wiley Periodicals, Inc.  相似文献   

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We discuss the parallelization of an efficient algorithm for the partial stabilization of large‐scale linear control systems in generalized state‐space form. The algorithm is composed of highly parallel iterative schemes that appear in the computation of certain matrix functions. Here we evaluate different approaches to exploit parallelism at two levels, based on threads and processes. Our experimental results on a cluster of symmetric multiprocessors and a CC‐NUMA platform show that the efficiency of the matrix operations underlying the iterative schemes carry over to the parallel implementation of the stabilization algorithm. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

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Mesh simplification is the process of reducing the number of triangles in a mesh representation of object surface. For a given level of detail or error tolerance, the conventional mesh simplification algorithms maximize the edge length globally, without explicitly considering local object shape. In this paper, we present a shape‐adaptive mesh simplification algorithm that locally maximizes edge length, depending on local shape. The proposed algorithm achieves shape‐adaptive simplification by iteratively maximizing edges between vertices, based on comparison with the ‘optimal’ edge lengths derived from local directional curvatures for a given error tolerance. Edge‐based processing facilitates the local shape adaptation and preserves sharp features. Experimental results demonstrate the efficacy of the proposed algorithm, by showing good visual quality and extremely small approximation error. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

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This article examines new issues resulting from applying case‐based reasoning (CBR) in e‐commerce and proposes a unified logical model for CBR‐based e‐commerce systems (CECS) that consists of three cycles and covers almost all activities of applying CBR in e‐commerce. This article also decomposes case adaptation into problem adaptation and solution adaptation, which not only improves the understanding of case adaptation in the traditional CBR, but also facilitates the refinement of activity of CBR in e‐commerce and intelligent support for e‐commerce. It then investigates CBR‐based product negotiation. This article thus gives insight into how to use CBR in e‐commerce and how to improve the understanding of CBR with its applications in e‐commerce from a logical viewpoint. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 29–46, 2005.  相似文献   

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