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基于像素运动的图像模糊机理与恢复技术 被引量:4
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作者 张秉仁 陈里铭 高游 《计算机工程》 CAS CSCD 北大核心 2004年第8期21-22,共2页
从像素运动的角度分析了因运动造成图像模糊的实际过程,根据模糊图像像素间的关系建立了一维和二维匀速直线运动所造成的模糊图像的模糊模型,进而由模糊过程的逆过程给出了恢复模型。最后对匀速直线运动造成的图像模糊进行了模拟和恢... 从像素运动的角度分析了因运动造成图像模糊的实际过程,根据模糊图像像素间的关系建立了一维和二维匀速直线运动所造成的模糊图像的模糊模型,进而由模糊过程的逆过程给出了恢复模型。最后对匀速直线运动造成的图像模糊进行了模拟和恢复,取得了令人满意的 效果。 展开更多
关键词 像素运动 模糊机理 模糊模型 恢复模型 一维运动 二维运动
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南方沿海地区电网标识牌褪色模糊机理分析
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作者 李宇峰 陈震霖 +4 位作者 吴培骋 赵志刚 黄庆淡 王茂春 林宏辉 《电力安全技术》 2022年第8期5-8,共4页
南方沿海地区湿度大、盐雾多、太阳光照时间长、紫外线强、雨水多、微生物活跃、工业区分布广,对电网标识牌寿命有较大影响。而现有的电网标识牌褪色模糊研究分析仅停留在现象表面,因此,从电网使用环境和材质本身深入分析电网标识牌褪... 南方沿海地区湿度大、盐雾多、太阳光照时间长、紫外线强、雨水多、微生物活跃、工业区分布广,对电网标识牌寿命有较大影响。而现有的电网标识牌褪色模糊研究分析仅停留在现象表面,因此,从电网使用环境和材质本身深入分析电网标识牌褪色模糊机理,并提出褪色模糊防治措施以减缓电网标识牌褪色模糊速率,延长其使用寿命,为电网标识牌防褪色模糊防治提供了新的思路。 展开更多
关键词 沿海地区 电网标识牌 褪色模糊机理 褪色模糊防治
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采用瞄准式杀伤技术的防空导弹总体问题研究 被引量:1
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作者 王志达 薛林 +1 位作者 陈阳阳 李建国 《现代防御技术》 北大核心 2024年第2期42-52,共11页
定向战斗部技术是利用目标方位信息通过导弹弹体变化或战斗部起爆逻辑控制改变爆破方向以取得最大毁伤效果的新型杀伤技术,是未来新一代防空导弹实现能力跨越的关键技术之一。以装备有径向转向式定向战斗部的瞄准杀伤式防空导弹为研究对... 定向战斗部技术是利用目标方位信息通过导弹弹体变化或战斗部起爆逻辑控制改变爆破方向以取得最大毁伤效果的新型杀伤技术,是未来新一代防空导弹实现能力跨越的关键技术之一。以装备有径向转向式定向战斗部的瞄准杀伤式防空导弹为研究对象,着重研究了相关总体问题。研究了补偿导弹法向过载的脱靶信息预测方法,满足了瞄准式杀伤提前获取脱靶信息的需求;研究了预测着靶点的散布规律和预测模糊问题的形成机理,为解决模糊问题提供了理论支撑;研究了小脱靶量遭遇时的瞄准精确度提升方法;对瞄准杀伤式防空导弹实例进行了仿真。 展开更多
关键词 瞄准式杀伤技术 脱靶信息预测 预测模糊机理 冗余杀伤 偏置控制
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一种模糊参数自适应控制器在直接转矩控制中的应用 被引量:3
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作者 李永坚 胡俊达 《中小型电机》 北大核心 2003年第5期29-32,共4页
采用一种基于模糊理论的自适应控制器作为三相异步电机直接转矩控制系统的速度调节器。重点介绍了控制器的模糊控制规则和模糊推理机理。试验证明比传统的PI控制器优越。
关键词 三相异步电机 直接转矩控制系统 速度调节器 模糊控制规则 模糊推理机理 模糊参数自适应控制器
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基于模糊加权最小二乘支持向量回归的非线性系统建模方法 被引量:1
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作者 熊中刚 刘忠 罗素莲 《探测与控制学报》 CSCD 北大核心 2019年第5期111-117,共7页
针对非线性系统建模时边界数据会产生较大的建模偏差、数据计算负荷大以及如何从数据集中选取K个近邻点才能保证其性能缺乏统一标准等问题,提出了基于模糊加权最小二乘支持向量回归的非线性系统建模方法。该方法融合了模糊加权机理与最... 针对非线性系统建模时边界数据会产生较大的建模偏差、数据计算负荷大以及如何从数据集中选取K个近邻点才能保证其性能缺乏统一标准等问题,提出了基于模糊加权最小二乘支持向量回归的非线性系统建模方法。该方法融合了模糊加权机理与最小二乘支持向量回归的优点,通过引入重叠因子,在保证建模精度(均方根误差越小越好)的情况下,去除建模过程中的一些非重要数据,减小建模方法的运算时间,并能将全局与局部建模方法相融合有效解决局部建模方法所产生的边界效应问题。实验验证结果表明,分别对几种方法从训练/测试均方根误差、不同重叠因子、计算时间方面比较都有明显的有效性和优越性。 展开更多
关键词 模糊加权机理 最小二乘支持向量回归 非线性统 建模方法
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ESTIMATION METHOD FOR AIRCRAFT SIMILARITY BASED ON FUZZY THEORY AND GREY INCIDENCE ANALYSIS 被引量:4
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作者 李永平 陈闵叶 刘明 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期194-198,共5页
An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the... An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the method of grey incidence analysis. Nine feature attributes of aircraft are selected to estimate the similarity between the new aircraft and the existing aircraft. A new aircraft X and other six existing aircrafts are taken as examples. Analyses show that similarity estimation results obtained from the method are in accordance with practice. 展开更多
关键词 aircraft similarity fuzzy theory grey incidence analysis
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GRADE-LIFE PROGNOSTIC MODEL OF AIRCRAFT ENGINE BEARING 被引量:6
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作者 苗学问 牛枞 +2 位作者 杨云 韩磊 洪杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期171-178,共8页
Research on practical and verifiable prediction methods for the service life of bearings plays a critical role in improving the reliability and safety of aircraft engines. The concept of grade-life (GL) is introduce... Research on practical and verifiable prediction methods for the service life of bearings plays a critical role in improving the reliability and safety of aircraft engines. The concept of grade-life (GL) is introduced to de- scribe the service life of bearings. A GL prognostic model for aircraft engine bearings is proposed based on sup- port vector machine (SVM) and fuzzy logic inference. Firstly, the mathematical model is discussed to predict the physics-based GL (PGL). Then, the diagnostic estimation model based on SVM is presented in detail to predict the empirical GL (EPL). Thirdly, a fuzzy logic inference is adopted to fuse two GL predicted results. Finally, the GL prognostic model is verified by the run-to-failure data acquired from an accelerated life test of an aircraft bearing. The results show that the model provides a more practical and reliable prediction for the service life of bearings. 展开更多
关键词 aircraft engine BEARING grade-life fuzzy logic inference SVM
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APPLICATION OF FUZZY INFERENCE IN IDENTIFICATION OF HELICOPTER MODEL
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作者 宋彦国 张呈林 徐锦法 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期124-129,共6页
Helicopter mathematical model mainly depends on design helicopter control system, flight simulator, and real time control simulation system. But it is difficult to establish a helicopter flight dynamics mathematical ... Helicopter mathematical model mainly depends on design helicopter control system, flight simulator, and real time control simulation system. But it is difficult to establish a helicopter flight dynamics mathematical model that has features such as rapidness, reliability and precision, because there is no unique and precise expression to some sophisticated phenomenon of helicopter. In this paper a fuzzy helicopter flight model is constructed based on the flight experimental data. The fuzzy model, which is identified by fuzzy inference, has characteristics of computed rapidness and high precision. In order to guarantee the precision of the identified fuzzy model, a new method is adopted to handle the conflict fuzzy rules. Additionally, using fuzzy clustering technology can effectively reduce the number of rules of fuzzy model, namely, the order of the fuzzy model. The simulation results indicate that the method of this paper is effective and feasible. 展开更多
关键词 helicopter mathematical model fuzzy inference fuzzy clustering flight control
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Developmental ecology of the American horseshoe crab Limulus polyphemus 被引量:5
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作者 Mark L.BOTTON Richard A.TANKERSLEY Robert E.LOVELAND 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第5期550-562,共13页
During spawning events, horseshoe crab eggs are released from the female's oviducts, and fertilized by one or more males. Eggs are shaped by the female into discrete clutches deposited in nests at depths of 10-20 cm ... During spawning events, horseshoe crab eggs are released from the female's oviducts, and fertilized by one or more males. Eggs are shaped by the female into discrete clutches deposited in nests at depths of 10-20 cm on intertidal estuarine beaches. Distinguishing between fxesh eggs and the early developmental stages is obfuscated by the large amount of dense, opaque yolk. The first unambiguous confirmation of development is the formation of the rudimentary prosomatie appendages at the "limb bud" stage. Several days thereafter, the outer chorion is shed and the developing embryo expands and undergoes a series of molts within the clear inner egg membrane. The trilobite (first iustar) stage thus attained may remain within the beach sedi- ments for several more weeks, until hatching is facilitated by environmental factors such as hydration, agitation, and osmotic shock that accompany the infiltration of seawater into the nests. Trilobites exhibit endogenous eirgatidal swimming rhythms that are entrained by mechanical agitation, suggesting that peaks in larval swimming are timed to coincide with periods of high water and the inundation of the nests. Larval swimming is limited and does not appear to result in long-distance dispersal. The limited dispersal of the larvae has important implications for the population dynamics of relatively isolated populations. The rate of larval development is highly plastic and is influenced by temperature, salinity, dissolved oxygen, and the presence of pollutants. The broad environmental tolerances of horseshoe crab embryos and larvae are important in understanding their current geographic distribution and their evolutionary persistence 展开更多
关键词 Horseshoe crab LIMULUS DEVELOPMENT EMBRYO Larval dispersal
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Development of single-chip fuzzy controller based on FFSI in binary 被引量:1
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作者 张吉礼 欧进萍 孙德兴 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期269-274,共6页
Length and concise structure of fuzzy logic reasoning program and its real-time reasoning characteris-tic have their effect on the performance of a digital single-chip fuzzy controller. The control effect of a digital... Length and concise structure of fuzzy logic reasoning program and its real-time reasoning characteris-tic have their effect on the performance of a digital single-chip fuzzy controller. The control effect of a digitalfuzzy controller based on looking up fuzzy control responding table is only relative to the table and not relative tothe fuzzy control rules in the practical control process. Aiming at above problem and having combined fuzzy log-ic reasoning with digital operational characteristics of a single-chip microcomputer, functioning-fuzzy-subset in-ference (FFSI) in binary, in which triangle membership functions of error and error-in-change are all represen-ted in binary and singleton membership functions of control variable is binary too, has been introduced. The cir-cuit principle plans of a single-chip fuzzy controller have been introduced for development of its hardware, andthe primary program structure, fuzzy logic reasoning subroutine, serial communication subroutine with PC andreliability design of the fuzzy controller are all discussed in detail. The control of indoor temperature by a fuzzycontroller has been conducted using a testing-room thermodynamic system. Research results show that the FFSIin binary can exercise a concise fuzzy control in a single-chip fuzzy controller, and the fuzzy controller is there-fore reliable and possesses a high performance-price ratio. 展开更多
关键词 functioning-fuzzy-subset inference single-chip fuzzy controller testing-room thermodynamic system indoor temperature experiment
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Influence of driver’s yielding behavior on pedestrian-vehicle conflicts at a two-lane roundabout using fuzzy cellular automata 被引量:2
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作者 LI Chuan-yao LIU Shi-kun +1 位作者 XU Guang-ming CEN Xue-kai 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期346-358,共13页
The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability a... The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability and pedestrian safety.Therefore,this study proposes a fuzzy cellular automata(FCA)model to explore the safety and efficiency impacts of pedestrian-vehicle conflicts at a two-lane roundabout.To reason the decision-making process of individual drivers before crosswalks,membership functions in the fuzzy inference system were calibrated with field data conducted in Changsha,China.Using specific indicators of efficiency and safety performance,it was shown that circulating vehicles can move smoothly in low traffic flow,but the roundabout system is prone to the traffic congestion if traffic flow reaches to a certain level.Also,the high yielding rate of drivers has a negative impact on the traffic efficiency but can improve pedestrian safety.Furthermore,a pedestrian restriction measure was deduced for the roundabout crosswalk from the FCA model and national guideline of setting traffic lights. 展开更多
关键词 ROUNDABOUT pedestrian-vehicle conflicts fuzzy inference system fuzzy cellular automata model pedestrian restriction measure
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Path-tracking Control of a Tractor-aircraft System 被引量:6
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作者 Nengjian Wang Hongbo Liu Wanhui Yang 《Journal of Marine Science and Application》 2012年第4期512-517,共6页
An aircraft tractor plays a significant role as a kind of important marine transport and support equipment. It's necessary to study its controlling and manoeuvring stability to improve operation efficiency. A virtual... An aircraft tractor plays a significant role as a kind of important marine transport and support equipment. It's necessary to study its controlling and manoeuvring stability to improve operation efficiency. A virtual prototyping model of the tractor-aircraft system based on Lagrange's equation of the first kind with Lagrange mutipliers was established in this paper, According to the towing characteristics, a path-tracking controller using fuzzy logic theory was designed. Direction control herein was carried out through a compensatory tracking approach. Interactive co-simulation was performed to validate the path-tracking behavior in closed-loop, Simulation results indicated that the tractor followed the reference courses precisely on a flat ground. 展开更多
关键词 path-tracking controller aircraft tractor preconcert route fuzzy control CO-SIMULATION
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Fuzzy TOPSIS method to primary crusher selection for Golegohar Iron Mine(Iran) 被引量:6
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作者 Mohammad Javad Rahimdel Mohammad Karamoozian 《Journal of Central South University》 SCIE EI CAS 2014年第11期4352-4359,共8页
Selection of the crusher required a great deal of design regarding to the mine planning. Selection of suitable primary crusher from all of available primary crushers is a multi-criterion decision making(MCDM) problem.... Selection of the crusher required a great deal of design regarding to the mine planning. Selection of suitable primary crusher from all of available primary crushers is a multi-criterion decision making(MCDM) problem. The present work explores the use of technique for order performance by similarity to ideal solution(TOPSIS) with fuzzy set theory to select best primary crusher for Golegohar Iron Mine in Iran. Gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impact crusher, hammer mill and feeder breaker crushers have been considered as alternatives. Also, the capacity, feed size, product size, rock compressive strength, abrasion index and application of primary crusher for mobile plants were considered as criteria for solution of this MCDM problem. To determine the order of the alternatives, closeness coefficient is defined by calculating the distances to the fuzzy positive ideal solution(FPIS) and fuzzy negative ideal solution(FNIS). Results of our work based on fuzzy TOPSIS method show that the gyratory is the best primary crusher for the studied mine. 展开更多
关键词 primary crusher multi-criterion decision making(MCDM) technique for order performance by similarity to ideal solution fuzzy set theory Golegohar Iron Mine gyratory crusher
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Status Evaluation of Loose of Jig Bed Based on Fuzzy Inference System 被引量:1
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作者 程健 郭一楠 +1 位作者 孙伟 穆俊英 《Journal of China University of Mining and Technology》 2003年第2期142-144,共3页
This paper mainly describes that loose of jig bed affects jig's separation effect, and the corresponding fuzzy rules were built. Using the evaluating index of jig's separation effect--imperfection (I) and tota... This paper mainly describes that loose of jig bed affects jig's separation effect, and the corresponding fuzzy rules were built. Using the evaluating index of jig's separation effect--imperfection (I) and total misplaced material (Cz), it evaluates status of loose of jig bed by fuzzy inference system. Experimental simulation and applications in practice prove the method's feasibility. 展开更多
关键词 JIG loose of jig bed fuzzy inference system
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Fuzzy Comprehensive Assessment Method to Determine Tectonic Stress Patterns
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作者 张海 戚蓝 +1 位作者 郝彩哲 郭磊 《Transactions of Tianjin University》 EI CAS 2007年第6期462-468,共7页
The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the direction... The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the directions of along-river, cross-river, shear clockwise, and shear counterclockwise , 26 types of tectonic stress patterns were presented. And the stress vector of each pattern was obtained with FE software by taking unit displacement as boundary load. Then, by taking the 26 types of tectonic stress patterns as index set and 3 main stresses as factor set and choosing various operators, comparison of directions of computational stress vector and survey stress vector was made and the most possible tectonic stress pattern was obtained. Taking the 26 types of tectonic stress patterns as index set and strike angle as factor set, comparison of relationships between formation of fault and tectonic stress was made,and the tectonic stress patterns were assessed with known fault information. By summarizing the above assessment results, the most impossible tectonic stress pattern was obtained . Finally an engineering case was quoted to validate that the method is more feasible and reliable than traditional empirical method. 展开更多
关键词 in-situ stress tectonic stress patterns fuzzy comprehensive assessment FAULT
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Generating Fuzzy Rule-based Systems from Examples Based on Robust Support Vector Machine
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作者 贾泂 张浩然 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期144-147,共4页
This paper firstly proposes a new support vector machine regression (SVR) with a robust loss function, and designs a gradient based algorithm for implementation of the SVR, then uses the SVR to extract fuzzy rules and... This paper firstly proposes a new support vector machine regression (SVR) with a robust loss function, and designs a gradient based algorithm for implementation of the SVR, then uses the SVR to extract fuzzy rules and designs fuzzy rule-based system. Simulations show that fuzzy rule-based system technique based on robust SVR achieves superior performance to the conventional fuzzy inference method, the proposed method provides satisfactory performance with excellent approximation and generalization property than the existing algorithm. 展开更多
关键词 support vector machine fuzzy rules rule-based system generalization.
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Probabilistic Fuzzy Hypermodules
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作者 詹建明 徐扬 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期125-128,共4页
We introduce the concept of T-fuzzy subhypermodules of hypermodules with respect to triangular norms and obtain some results. In particular, we define a probabilistic version of hypermodules using random sets and show... We introduce the concept of T-fuzzy subhypermodules of hypermodules with respect to triangular norms and obtain some results. In particular, we define a probabilistic version of hypermodules using random sets and show that fuzzy hypermodules defined in triangular norms are consequences of probabilistic hypermodules under certain conditions. 展开更多
关键词 T-fuzzy subhypermodule hypermodule probability space random set.
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Objective function of cost in optimal tolerance allocation
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作者 王瑜 翟文杰 +3 位作者 杨立平 吴伟国 姬舒平 马玉林 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第6期741-746,共6页
An objective function model is proposed for cost in optimizing and allocating tolerance with consideration of manufacturing conditions. With the fuzzy comprehensive evaluation method,a manufacturing difficulty coeffic... An objective function model is proposed for cost in optimizing and allocating tolerance with consideration of manufacturing conditions. With the fuzzy comprehensive evaluation method,a manufacturing difficulty coefficient is derived,which takes into account of several factors affecting the manufacturing cost,including the forming means of the blank,size,machining surface features,operator’s skills and machinability of materials. The coefficient is then converted into a weight factor used in the inversed square model representing the relationship between the cost and tolerance,and,hence,an objective function for cost is established in optimizing and allocating tolerance. The higher is the manufacturing difficulty coefficient,the higher is the relative manufacturing cost and the higher is the weight factor of the tolerance allocation,which indicates the increase of the tolerance’s effects on the total manufacturing cost and,therefore,a larger tolerance should be allocated. The computer-aided tolerance allocation utilizing this model makes it more convenient,accurate and practicable. 展开更多
关键词 computer-aided tolerance allocation cost tolerance model fuzzy comprehensive evalnatinn manufacturing difficulty coefficient
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Application of Fuzzy Automata Theory and Knowledge Based Neural Networks for Development of Basic Learning Model
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作者 Manuj Darbari Hasan Ahmed Vivek Kr. Singh 《Computer Technology and Application》 2011年第1期58-61,共4页
The paper focuses on amalgamation of automata theory and fuzzy language. It uses adaptive knowledge based abstract framework which uses dynamic neural network framework along with fuzzy automata as Models of Learning,... The paper focuses on amalgamation of automata theory and fuzzy language. It uses adaptive knowledge based abstract framework which uses dynamic neural network framework along with fuzzy automata as Models of Learning, combining the two methodologies the authors develop a new framework termed as Fuzzy Automata based Neural Network (FANN). It highlights conversion of knowledge rule to fuzzy automata thereby generating a framework FANN. FANN consists of composite fuzzy automation divided into "Performance Evaluator" and "Feature Extraction" which takes the help of previously stored samples of similar situations. The authors have extended FANN for Urban Traffic Modeling. 展开更多
关键词 Fuzzy logic automata theory urban traffic systems.
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Modeling Multisource-heterogeneous Information Based on Random Set and Fuzzy Set Theory
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作者 文成林 徐晓滨 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期87-92,共6页
This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. First... This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. Firstly, based on strong random set and weak random set, the unified form to describe both data (unambiguous information) and fuzzy evidence (uncertain information) is introduced. Secondly, according to signatures of fuzzy evidence, two Bayesian-markov nonlinear measurement models are proposed to fuse effectively data and fuzzy evidence. Thirdly, by use of "the models-based signature-matching scheme", the operation of the statistics of fuzzy evidence defined as random set can be translated into that of the membership functions of relative point state variables. These works are the basis to construct qualitative measurement models and to fuse data and fuzzy evidence. 展开更多
关键词 random set theory DATA fuzzy evidence fuzzy membership functions qualitative measurement model.
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