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1.
A new approach to fuzzy modeling   总被引:7,自引:0,他引:7  
This paper proposes a new approach to fuzzy modeling. The suggested fuzzy model can express a given unknown system with a few fuzzy rules as well as Takagi and Sugeno's model (1985), because it has the same structure as that of Takagi and Sugeno's model. It is also as easy to implement as Sugeno and Yasukawa's model (1993) because its identification mimics the simple identification procedure of Sugeno and Yasukawa's model. The suggested algorithm is composed of two steps: coarse tuning and fine tuning. In coarse tuning, fuzzy C-regression model (FCRM) clustering is used, which is a modified version of fuzzy C-means (FCM). In fine tuning, gradient descent algorithm is used to precisely adjust parameters of the fuzzy model instead of nonlinear optimization methods used in other models. Finally, some examples are given to demonstrate the validity of this algorithm  相似文献   

2.
A formal approach to fuzzy modeling   总被引:1,自引:0,他引:1  
A formalism for coding fuzzy models of dynamical systems is presented. It is shown that the formalism is rich enough to capture the performance of arbitrary conventional discrete time dynamical systems whose transition maps are polynomials with rational coefficients. The proof of this fact provides a constructive algorithm for generating fuzzy models to arbitrarily closely approximate an arbitrary map on a compact set. Our modeling formalism highlights the similarities between fuzzy systems and hybrid control systems. We hope to be able to exploit these similarities by extending results from the area of hybrid systems to the fuzzy domain and vice versa  相似文献   

3.
4.
This study proposes a hybrid robust approach for constructing Takagi–Sugeno–Kang (TSK) fuzzy models with outliers. The approach consists of a robust fuzzy C-regression model (RFCRM) clustering algorithm in the coarse-tuning phase and an annealing robust back-propagation (ARBP) learning algorithm in the fine-tuning phase. The RFCRM clustering algorithm is modified from the fuzzy C-regression models (FCRM) clustering algorithm by incorporating a robust mechanism and considering input data distribution and robust similarity measure into the FCRM clustering algorithm. Due to the use of robust mechanisms and the consideration of input data distribution, the fuzzy subspaces and the parameters of functions in the consequent parts are simultaneously identified by the proposed RFCRM clustering algorithm and the obtained model will not be significantly affected by outliers. Furthermore, the robust similarity measure is used in the clustering process to reduce the redundant clusters. Consequently, the RFCRM clustering algorithm can generate a better initialization for the TSK fuzzy models in the coarse-tuning phase. Then, an ARBP algorithm is employed to obtain a more precise model in the fine-tuning phase. From our simulation results, it is clearly evident that the proposed robust TSK fuzzy model approach is superior to existing approaches in learning speed and in approximation accuracy.  相似文献   

5.
A transformed input-domain approach to fuzzy modeling   总被引:2,自引:0,他引:2  
This paper presents an explanation of a fuzzy model considering the correlation among components of input data. Generally, fuzzy models have a capability of dividing an input space into several subspaces compared to a linear model. But hitherto suggested fuzzy modeling algorithms have not taken into consideration the correlation among components of sample data and have addressed them independently, which results in an ineffective partition of the input space. In order to solve this problem, this paper proposes a new fuzzy modeling algorithm, which partitions the input space more effectively than conventional fuzzy modeling algorithms by taking into consideration the correlation among components of sample data. As a way to use the correlation and divide the input space, the method of principal component is used. Finally, the results of the computer simulation are given to demonstrate the validity of this algorithm  相似文献   

6.
Despite research showing that interaction between the elderly and young people is beneficial to the health and well-being of both, little is known about the grandparent–grandchild relationship. Consequently, it is difficult to make informed design decisions about technologies to support their intergenerational interactions. This paper investigates one particularly important type of intergenerational interaction, namely play. The paper presents research that examines grandparent–grandchildren interactions in preschool playgroups. Through the use of vignettes drawn from observation of playful activity, pertinent features of intergenerational play are identified, focussing on the roles grandparents and grandchildren use when playing together. The results are relevant to researchers wishing to understand intergenerational play and to technology designers wanting to support it.  相似文献   

7.
Recently, the study of incorporating probability theory and fuzzy logic has received much interest. To endow the traditional fuzzy rule-based systems (FRBs) with probabilistic features to handle randomness, this paper presents a probabilistic fuzzy neural network (ProFNN) by introducing the probability of input linguistic terms and providing linguistic meaning into the connectionist architecture. ProFNN integrates the probabilistic information of fuzzy rules into the antecedent parts and quantifies the impacts of the rules on the consequent parts using mutual subsethood, which work in conjunction with volume defuzzification in a gradient descent learning frame work. Despite the increase in the number of parameters, ProFNN provides a promising solution to deal with randomness and fuzziness in a single frame. To evaluate the performance and applicability of the proposed approach, ProFNN is carried out on various benchmarking problems and compared with other existing models with a performance better than most of them.  相似文献   

8.
Human emotion expressed in social media plays an increasingly important role in shaping policies and decisions. However, the process by which emotion produces influence in online social media networks is relatively unknown. Previous works focus largely on sentiment classification and polarity identification but do not adequately consider the way emotion affects user influence. This research developed a novel framework, a theory-based model, and a proof-of-concept system for dissecting emotion and user influence in social media networks. The system models emotion-triggered influence and facilitates analysis of emotion-influence causality in the context of U.S. border security (using 5,327,813 tweets posted by 1,303,477 users). Motivated by a theory of emotion spread, the model was integrated in an influence-computation method, called the interaction modeling (IM) approach, which was compared with a benchmark using a user centrality (UC) approach based on social positions. IM was found to have identified influential users who are more broadly related to U.S. cultural issues. Influential users tended to express intense emotions of fear, anger, disgust, and sadness. The emotion trust distinguishes influential users from others, whereas anger and fear contributed significantly to causing user influence. The research contributes to incorporating human emotion into the data-information-knowledge-wisdom model of knowledge management and to providing new information systems artifacts and new causality findings for emotion-influence analysis.  相似文献   

9.
Ben  Yunlong  Xiaoxian  Hai   《Neurocomputing》2008,71(7-9):1436-1448
Inspired by the phenomenon of symbiosis in natural ecosystems a multi-swarm cooperative particle swarm optimizer (MCPSO) is proposed as a new fuzzy modeling strategy for identification and control of non-linear dynamical systems. In MCPSO, the population consists of one master swarm and several slave swarms. The slave swarms execute particle swarm optimization (PSO) or its variants independently to maintain the diversity of particles, while the particles in the master swarm enhance themselves based on their own knowledge and also the knowledge of the particles in the slave swarms. With four benchmark functions, MCPSO is proved to have better performance than PSO and its variants. MCPSO is then used to automatically design the fuzzy identifier and fuzzy controller for non-linear dynamical systems. The proposed algorithm (MCPSO) is shown to outperform PSO and some other methods in identifying and controlling dynamical systems.  相似文献   

10.
Conventional portfolio optimization models have an assumption that the future condition of stock market can be accurately predicted by historical data. However, no matter how accurate the past data is, this premise will not exist in the financial market due to the high volatility of market environment. This paper discusses the fuzzy portfolio optimization problem where the asset returns are represented by fuzzy data. A mean-absolute deviation risk function model and Zadeh’s extension principle are utilized for the solution method of portfolio optimization problem with fuzzy returns. Since the parameters are fuzzy numbers, the gain of return is a fuzzy number as well. A pair of two-level mathematical programs is formulated to calculate the upper bound and lower bound of the return of the portfolio optimization problem. Based on the duality theorem and by applying the variable transformation technique, the pair of two-level mathematical programs is transformed into a pair of ordinary one-level linear programs so they can be manipulated. It is found that the calculated results conform to an essential idea in finance and economics that the greater the amount of risk that an investor is willing to take on, the greater the potential return. An example, which utilizes the data from Taiwan stock exchange corporation, illustrates the whole idea on fuzzy portfolio optimization problem.  相似文献   

11.
In this paper a hybrid learning system that combines different fuzzy modeling techniques is being investigated. In order to implement the different methods, we propose the use of intelligent agents, which collaborate by means of a multiagent architecture. This approach, involving agents which embody the different problem solving methods, is a potentially useful strategy for enhancing the power of fuzzy modeling systems. ©1999 John Wiley & Sons, Inc.  相似文献   

12.
ABSTRACT

This article discusses methodological considerations of user-centred design for non-human animals. These considerations are illustrated through a design research project that aims to apply digital technology to build games for orangutans’ enrichment. The article argues that design for other species reveals limitations of designers’ knowledge of prospected users. The article explores how to approach participants who cannot express themselves verbally and how to recognise play that may not look familiar to the designer. The article finally presents a participatory design method that allows for non-human contributions in design. This method applies play as an interspecies co-creative act and can be used as a starting point for addressing questions of difference in play and designing games that allow for ambiguous play.  相似文献   

13.
用于生理信号情感识别的自适应遗传算法   总被引:3,自引:0,他引:3  
针对用生理信号识别情感中的最优情感特征组合的选择这一组合优化问题,将遗传算法中的交叉、变异操作加以改进形成新的算法.该算法用来选择最能代表相应情感状态的最优特征组合,并以最近邻法的分类正确率作为当前搜索到的最优特征组合的评价准则,对joy、anger、pleasure、sadness这4种情感状态进行识别,得到了较好的情感识别效果.仿真实验表明了该方法的可行性和有效性.  相似文献   

14.
A new approach to fuzzy modeling and control of discrete-time systems   总被引:3,自引:0,他引:3  
We present a new approach to fuzzy modeling and control of discrete-time systems which is based on the formulation of a novel state-space representation using the hyperbolic tangent function. The new representation, designated the hyperbolic model, combines the advantages of fuzzy system theory and classical control theory. On the one hand, the hyperbolic model is easily derived from a set of Mamdani-type fuzzy rules. On the other hand, classical control theory can be applied to design controllers for the hyperbolic model that not only guarantee stability and robustness but are themselves equivalent to a set of Mamdani-type fuzzy rules. Thus, this new approach combines the best of two worlds. It enables linguistic interpretability of both the model and the controller, and guarantees closed-loop stability and robustness.  相似文献   

15.
This paper proposes MULTIMOORA-IFN2 technique for multi-criteria decision making MCDM). The proposed approach involves information fusion which allows considering information expressed in both crisp and fuzzy variables. What is more, we introduce the aggregation of the different parts of MULTIMOORA which makes the technique more operational, especially in case of large-scale applications. The empirical example considers the case of energy storage technology selection. The sensitivity of the results obtained by applying MUTIMOORA-IFN2 is checked in two ways. The weighting is adjusted to ascertain whether the changes in the importance of the criteria impact the ranks of the energy storage technologies. Further on, the results obtained by applying MULTIMOORA-IFN2 are compared to those obtained by employing TOPSIS and VIKOR methods.  相似文献   

16.
基于F-SVMs的多模型建模方法   总被引:4,自引:1,他引:4  
针对全局模型难以精确描述复杂工业过程的问题,提出一种基于模糊支持向量机(F-SVMs)的多模型(F-SVMs MM)建模方法。用模糊支持向量分类算法(F-SVC)对输入数据进行预处理,得到多模型模糊隶属度;用模糊支持回归算法(F-SVR)建立多模型(MM)估计器。应用该方法对pH中和滴定过程进行建模,仿真结果表明,F-SVMs MM跟踪性能好、泛化能力强,比USOCPN方法和标准支持向量机(SVMs)方法具有更好的性能和推广能力。  相似文献   

17.
The paper proposes a novel approach to fuzzy modeling of human working memory (WM) using electroencephalographic (EEG) signals, acquired during human face encoding and recall experiments in connection with a face recognition problem. The EEG signals acquired from the short term memory (STM) during memory encoding instances are considered as the input of the proposed working memory model. On the other hand, the EEG response of the WM to visual stimuli acquired during WM recall instances are considered as the output of the proposed working memory model. The entire experiment is primarily divided into two phases. In the first phase, the WM of a human subject is modeled by a fuzzy implication relation, describing a mapping from the STM response (during encoding) to the WM responses (during recall) to visual stimuli. During STM encoding, the subject is visually presented with the full face stimulus of a person. During WM recall, four partial face stimuli of the same person (made familiar during encoding) are used for the subject to recall the respective full face.The second phase is undertaken to validate the WM model by visually stimulating the subject again with randomly selected partial faces of people, being familiar in the first phase and the WM EEG responses are recorded. The WM responses along with the WM model, developed in the first phase, are used to retrieve the STM information by using an inverse fuzzy (implication) relation. Besides WM modeling, another important contribution of the paper lies in devising a solution to the inverse fuzzy relation computation in the settings of an optimization problem. An error metric is then defined to measure the discrepancy between the model-predicted STM encoding pattern and the actual pattern encoded by the STM (as captured by the EEG signal during encoding in the first phase). Apparently, smaller the error magnitude better is the accuracy of the proposed model to effectively differentiate people with memory failures. Experimentally it is observed that the proposed model yields a very small error, in the order of 10−4, thus showing a high level of similarity between actual and model predicted STM response for all the healthy subjects. An experiment undertaken using eLORETA software confirms that the orbito-frontal cortex of prefrontal lobe is responsible for STM encoding whereas dorsolateral prefrontal region is responsible for WM recall. An analysis undertaken reveals that the proposed WM model produces the best response in the theta frequency band of EEG spectra, thus assuring the association of the theta frequency range in the face recognition task. Comparative analysis performed also substantiates that the proposed technique of computing max–min inverse fuzzy relation outperforms the existing techniques for inverse fuzzy computation, with a successful retrieval accuracy of 87.92%. The proposed study would find interesting applications to diagnose memory failures for people with Pre-frontal lobe amnesia.  相似文献   

18.
In the current literature dealing with job shop scheduling, most of the approaches have developed models based on the assumption that the problem domain does not contain any imprecision. However, this hypothesis is strongly challenged in the implementation phase of such models-imprecision is inherent to production systems involving human intervention. The aim of this paper is to demonstrate the advantages of possibilistic production data modeling in a real-world application, i.e., semiconductor manufacturing. In this work, a discrete-event simulation model (MELISSA) for performance evaluation of a batch-manufacturing facility previously developed in our laboratory has been extended to treat uncertainties modeled by fuzzy numbers. Due to the confidential nature of industrial data, an illustrative example, presenting the same typical features as a real problem, is treated and analyzed using fuzzy concepts. Inclusion of fuzzy techniques provides the decision-maker with a range of possible values for completion times, average storage times, and operator workload instead of a unique value (which has little significance due to the variety of human operators). In addition, the negative portion of average waiting times yields useful information for the manager to detect deficient resources in the production system  相似文献   

19.
20.
This paper presents a systematic approach to design first order Tagaki-Sugeno-Kang (TSK) fuzzy systems. This approach attempts to obtain the fuzzy rules without any assumption about the structure of the data. The structure identification and parameter optimization steps in this approach are carried out automatically, and are capable of finding the optimal number of the rules with an acceptable accuracy. Starting with an initial structure, the system first tries to improve the structure and, then, as soon as an improved structure is found, it fine tunes its rules’ parameters. Then, it goes back to improve the structure again to find a better structure and re-fine tune the rules’ parameters. This loop continues until a satisfactory solution (TSK model) is found. The proposed approach has successfully been applied to well-known benchmark datasets and real-world problems. The obtained results are compared with those obtained with other methods from the literature. Experimental studies demonstrate that the predicted properties have a good agreement with the measured data by using the elicited fuzzy model with a small number of rules. Finally, as a case study, the proposed approach is applied to the desulfurization process of a real steel industry. Comparing the proposed approach with some other fuzzy systems and neural networks, it is shown that the developed TSK fuzzy system exhibits better results with higher accuracy and smaller size of architecture.  相似文献   

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