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The cut sets,decomposition theorems and representation theorems on intuitionistic fuzzy sets and interval valued fuzzy sets

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Science china(Information Sciences) 2011年第1期54卷 91-110页

作者： YUAN XueHai,LI HongXing & SUN KaiBiao school of electronic and Information engineering,Dalian university of technology,Dalian 116024,china school of electronic and Information engineering Dalian University of Technology Dalian China

In this paper,the cut sets,decomposition theorems and representation theorems of intuitionistic fuzzy sets and interval valued fuzzy sets are researched ***,new definitions of four kinds of cut sets on intuitionistic fuzzy sets are introduced,which are generalizations of cut sets on Zadeh fuzzy sets and have the same properties as that of Zadeh fuzzy ***,based on these new cut sets,the decomposition theorems and representation theorems on intuitionistic fuzzy sets are *** kind of cut sets corresponds to two kinds of decomposition theorems and representation *** eight kinds of decomposition theorems and representation theorems on intuitionistic fuzzy sets are obtained,*** last,new definitions of cut sets on interval valued fuzzy sets are given based on the theory of cut sets on intuitionistic fuzzy sets,and eight kinds of decomposition theorems and representation theorems on interval valued fuzzy sets are also obtained. These results provide a fundamental theory for the research of intuitionistic fuzzy sets and interval valued fuzzy sets.

关键词： intuitionistic fuzzy sets interval valued fuzzy sets triple valued fuzzy sets cut sets decomposition theorem representation theorem

Stability of impulsive stochastic functional differential systems in terms of two measures via comparison approach

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Science china(Information Sciences) 2012年第6期55卷 1313-1322页

作者： YAO FengQi 1,2 & DENG FeiQi 1 1 Institute of System engineering,South china university of technology,Guangzhou 510640,china 2 school of electrical engineering and Information,Anhui university of technology,Maanshan 243032,china Institute of System engineering South China University of Technology Guangzhou China school of electrical engineering and Information Anhui University of Technology Maanshan China

Comparison principles for general impulsive stochastic functional differential systems are *** the comparison principles and the theory of differential inequalities,stability and instability,involving two measures,of impulsive stochastic functional differential systems are *** stability and instability criteria are obtained,and two examples are also given to illustrate our results.

关键词： stochastic systems impulsive functional differential systems comparison principle stability in terms of two measures instability

Design of UWB bandpass filter with dual notched bands

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Science china(Information Sciences) 2012年第6期55卷 1436-1440页

作者： CHU QingXin & TIAN XuKun school of electronic and Information engineering,South china university of technology,Guangzhou 510640,china school of electronic and Information engineering South China University of Technology Guangzhou China

An ultra-wideband (UWB) bandpass filter (BPF) with dual sharply rejected notch-bands to elim-inate the interference from coexisting radio systems is presented in this *** characteristics of the proposed notched structure are investigated using simulations to demonstrate the design flexibility of the notch-band *** integrating the proposed notched structure into the basic UWB BPF based on a stepped-impedance stub loaded resonator (SISLR),a UWB BPF with dual sharply rejected notched bands at 5.2 and 5.8 GHz is ***,the designed filter is built and *** simulated and measured results are found to be in good agreement to verify the proposed design.

关键词： bandpass filter bandstop units notched bands ultra-wideband

A new satellite to satellite tracking algorithm from Doppler-shifted frequency measurements

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Progress in Natural Science:Materials International 2007年第10期17卷 1226-1234页

作者： Li Qiang, Guo Fucheng and Zhou Yiyu(school of electronic Science & engineering, National university of Defense technology, Changsha 410073, china) school of electronic Science and engineering National University of Defense Technology Changsha 410073 China

A new satellite to satellite tracking (SST) algorithm from Doppler-shifted frequency measurements is proposed. The estimation principle is demonstrated and the mathematic model of SST is established. The state estimation methods for a user (the cooperative case) and target satellites (the non-cooperative case) are presented based on particle swarm optimization (PSO). The Cramer-Rao lower bounds (CRLB) are deduced as well. Performance of the new algorithm is validated through computer simulations, which proved that the proposed method is effective in terms of the estimation quality compared with CRLB and superior in accuracy to the Bearings-Only (BO) method in almost all simulation cases except for the case that an enough long tracking arc-length is obtained for a user satellite.

关键词： satellite to satellite tracking (SST) Doppler-shifted frequency (DSF) Space Surveillance Network (SSN) particle swarm optimization (PSO).

Improving anti-sulfur performance of methane sensors by new vectors and active components

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Mining Science and technology 2010年第6期20卷 913-916页

作者： WANG Ying, TONG Minming, ZHANG Tao school of Information and electrical engineering, china university of Mining & technology, Xuzhou 221008, china school of Information and electrical engineering China University of Mining & Technology Xuzhou 221008 China

Conventional Pd/?-Al2O3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent de-crease in sensitivity and the working life of methane sensors. We mainly investigated the effect of nanotechnology and a cerium co-catalyst on the stability and anti-sulfur performance of methane sensors. In our experiment, an anti-sulfur methane sensor was prepared by immersing cerium-containing ?-alumina nanometer elements into a Pt-Pd bimetallic nanometer catalyst. The experi-ment about the sensitivity and stability performance of different catalytic methane sensors indicate that sensitivity, decreased by catalyst sulfur poisoning, is improved significantly by adding cerium to the vector. As well, the long-term operational stability of methane sensors increased significantly.

关键词：载体催化元件抗硫性能有源元件甲烷传感器纳米催化剂纳米氧化铝稳定性能工作寿命

Numerical calculation on temperature field of FGH95 alloy droplet during rapid solidification

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Journal of university of Science and technology Beijing 2003年第3期10卷 51-54页

作者： Huanming Chen and Benfu Hu Materials Science and engineering school, university of Science and technology Beijing, Beijing 100083,china Physics and electrical Information engineering school, Ningxia university, Yinchuan 750021,china Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Ningxia Univ Phys & Elect Informat Engn Sch Yinchuan 750021 Peoples R China

The temperature field of FGH95 alloy droplet atomized by plasma rotatingelectrode processing (PREP) during solidification has been calculated through numerical analysisbased on equivalent sensible heat capacity method. And thus the relational curves among temperaturegradient of solid-liquid interface, moving velocity of solid-liquid interface and solid fractionduring solidification have been presented. The results indicate that the relation between averagetemperature gradient of solid-liquid interface and droplet size, and the relation between averagemoving velocity of solid-liquid interface and droplet size can be expressed during solidification.

关键词： FGH95 alloy droplet temperature field numerical calculation

THEORETICAL DESIGN AND MOTION PLANNING OF NONHOLONOMIC MANIPULATOR

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Chinese Journal of Mechanical engineering 2004年第2期17卷 222-225页

作者： Tan Yuegang Deng Yuhui WU Zhengping school of Mechanical and electronic engineering,Wuhan university of technology,Wuhan 430070, china school of Mechanical and electronic engineering Wuhan University of Technology Wuhan 430070

A new nonholonomic transmission mechanism is proposed based on thenonholonomic theory and nonlinear control principle, and combined with conditions of thenonholonomic motion planning and control, that is researched to compose method of the motiontransfer chain from this transmission mechanism, on which a new nonholonomic manipulator isdesigned. This nonholonomic manipulator is a controllable multi-joint manipulator that actuated onlyby two-servo electromotor. Its motion expresses the characteristic of nonholonomy constraint andnonlinear, and that also satisfies the chained form convertibility. And then, using the nonlinearcontrol principle of chained system, motion characteristic of the nonholonomic manipulator isapplied. From simulation verification and analysis, the usefulness of the theoretical design andcontrol strategies is shown, and that is important in design and research of handiness robot andmulti-finger robot hand.

关键词： Nonholonomic system Nonholonomic motion planning Nonlinear controlMulti-joint Manipulator

Effect of Asymmetry in a Bistable System Subject to Multiplicative Colored Noise

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Communications in Theoretical Physics 2007年第12期48卷 1059-1062页

作者： ZHOU Yu-Rong~(1,2)GUO Feng~3 and PANG Xiao-Feng~1~1 school of Life Science and technology,university of electronic Science and technology of china,Chengdu 610054,china~2 school of Information and Electric engineering,Panzhihua university,Panzhihua 617000,china~3 school of Automation engineering,university of electronic Science and technology of china,Chengdu 610054,china school of Life Science and technology University of Electronic Science and Technology of China Chengdu 610054 China school of Information and Electric engineering Panzhihua University Panzhihua 617000 China school of Automation engineering University of Electronic Science and Technology of China Chengdu 610054 China

By the method of the stochastic energetics,we investigate the stochastic resonance (SR) phenomenon of anoverdamped Brown particle in an asymmetric bistable potential,driven by external periodical signal and *** expressions have been obtained for the quasi-steady-state probability distribution *** is found thatthe input energy (IE) pumped into the system by the external driving shows an SR-like behavior as a function of thenoise strength,whereas the IE turns to be a monotonic function of the correlation time of the *** effect ofpotential asymmetry is also studied on SR and IE.

关键词： asymmetric bistable system stochastic resonance stochastic energetics

A type of M2 -transmitter N2 -receiver MIMO radar array and 3D imaging theory

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Science china(Information Sciences) 2011年第10期54卷 2147-2157页

作者： ZHU YuTao & SU Yi school of electronic Science and engineering,National university of Defense technology,Changsha 410073,china school of electronic Science and engineering National University of Defense Technology Changsha China

With two-dimensional synthetic apertures,a wideband radar array can realize 3D imaging of air targets,but this needs large numbers of antenna ***,when the transmitting frequency is very high,the interval of array elements makes it hard to fit the available space,which makes the imaging resolution *** paper proposes a type of M 2 -transmitter N 2 -receiver multiple-input multiple-output (MIMO) radar,which is equivalent to a rectangular radar array with (M N) 2 T/R antenna elements based on phase center approximation theory,and which can realize the 3D imaging of air *** 3D imaging theory and MIMO inverse synthetic aperture radar (MIMO-ISAR) 3D imaging theory are also proposed in this paper,and two simulations are given to show their validity.

关键词： MIMO radar array phase center approximation 3D imaging ISAR