Papers by Keyword: Fuzzy

Abstract: With the rapid development of China's economy, an unprecedented breakthrough is also achieved in the urbanization construction speed. This paper first introduces the principle of method for evaluation of urbanization, then selects the indicator system of urbanization in Xianning mountain, and builds up a set of indicator system for evaluation of urbanization in mountainous area in Xianning with AHP, conducts a fuzzy comprehensive evaluation of urbanization of mountainous area in Xianning; finally, the evaluation result is analyzed.

Abstract: Congestion management is a hot point for research in power system. Optimal power flow (OPF) model is often used to solve this problem. However, the results cannot satisfy with market needing. To solve this problem, this paper presents a novel method of congestion management based on risk constraint and fuzzy optimization in electricity power markets. The risk constraint is used for transmission line thermal security instead of the traditional deterministic current or power constraint. The multi-objective functions are used to coordinate the conflict between security and efficiency of transmission network. Primal-Dual Interior Point Method (PDIPM) is adopted to solve the RBOPF problem. The method can minimize re-dispatch cost and the system operating risk.

Abstract: Classical time series model can efficiently handle many forecasting problems, but these models can not solves the forecasting problem in which values of the time series are represented by language values or fuzzy sets. Song and Chissom and many other scholars put forward many models, and these models can only forecast research about historical data. This paper presents a new fuzzy time series forecasting model which can predict the data of unknown years.

Abstract: For a class of T-S fuzzy time-delay systems, the problem of designing a static output feedback controller is considered via the parallel distributed compensation (PDC) approach. Namely, when one controller can not assure the stability of system, a controller switching strategy in certain set of controllers may stabilize the system. Moreover the adoption of this strategy often improves the performance of system even in the case that a single controller can stabilize the system. By defining multiple Lyapunov functions, the sufficient condition for the existence of the static out put feedback controller is presented in terms of linear matrix inequality (LMI), which guarantees the stability of the close-loop system for the switching cases. The simulation results demonstrate the effectiveness of the proposed method.

Abstract: In order to ensure work safety, large cranes generally use two motors together to upgrade the load, so often there is a synchronization error, control accuracy is affected. To address this issue, the paper crane hydraulic lifting system to study proposed control strategy based on fuzzy PID's. The results show that the method used to effectively reduce the synchronization error between the two motors to improve the control precision crane, a certain reference value.

Abstract: In this study, a fuzzy credibility constrained programming (FCCP) model is developed for agricultural irrigation systems management under uncertainty. It is then applied to a real case study in a depression at southern Urumqi, China. The optimization model can be adjusted according to various considerations from decision makers, and thus much optimal and applicable management strategies can be expected through identifying the most appropriate credibility level for the system.

Abstract: Cut angle is one of the best important parameters of chimney demolished by controlled blasting. The suitable angle is effected by a lot of factors. But mechanical principle is not entirely clear. The theoretical value of angle is usually designed by experience formula . At the same time, the factual angle made by blasting is also fuzzy and random. So in this paper, the formula to calculate fuzzy reliability of cut angle is derived according to fuzzy reliability theory. It provides an credible parameter for engineering blasting designer. Linear memberships function is adopted for theory value of cut angle and the factual blasting angle is a random variable which is suggested to be normally distributed. At last, an engineering example is given to verify the method of this paper.

Abstract: This paper is Zhengli Coal JKMD3.5 × 4 (III) E-type floor-type multi-rope friction hoist for the study, in order to enhance the system to improve monitoring and fault diagnosis for the purpose of fuzzy fault tree analysis method as the lift system the method of fault diagnosis on hoist brake system fault tree analysis, the results of the analysis can play a guiding role in the daily repair and maintenance, thereby enhancing the safety and reliability of the hoist.

Abstract: As the information weapons large role in information war, the battlefield electromagnetic environment becomes more and more complex, and having a profound impact on operations, in order to make the controller in the complex battlefield electromagnetic environment for the correct decisions, need to evaluate the electromagnetic environment. In this paper , based on the battlefield electromagnetic environment elements are introduced, on the battlefield electromagnetic environment are classified and analyzed the complexity of electromagnetic environmental assessment of general evaluation and complexity of specific evaluation methods, on the battlefield electromagnetic environment assessment has important application value.

Abstract: The data classification is an important issue in massive data classification. This paper proposes an inter-cell classification algorithm based on phase recombination neighbor points convergence which analyzes the convergence value weights of inter-cell characteristic points and filter the interferences of the minority local optimal characteristic points. The proposed algorithm can promote the convergence of the inter-cell classification data neighbor points. The simulation experiments testify the models by three types of actually collected data sets which illustrate the models have better classification performance.