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Improving the Structure of Multiple Dimension Turbo Codes Using Multiple Identical Component Encoders

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Wuhan university Journal of Natural Sciences 2010年第4期15卷 330-334页

作者： WANG Zhenghai1, TIAN Mao1, WANG Yuhao2.1. school of Electronic Information, Wuhan university, Wuhan 430072. Hubei,{2. 2. school of Information engineering, nanchang university, nanchang 330031, jiangxi,{2. school of Electronic Information Wuhan University Wuhan Hubei China school of Information engineering Nanchang University Nanchang Jiangxi China

In this paper,we propose an improved structure for M-dimension ( M ≥ 2.turbo codes using M identical component encoders. The presented structure only applies single recursive convolutional encoder to encode M interleaved versions of infor-mation sequence and single tail sequence to operate termination. For the commonly used two-dimension (M = 2. turbo codes,two cascade soft input soft output (SISO) decoders are detailed to de-code the corresponding codes. With the two cascade SISO decod-ers,this coding structure obviously outperforms traditional turbo codes at high code rates,especially,about 0.3 dB gain can be ob-tained at code rate 0.9 in additive white Gaussian noise channel with quadrature phase shift keying modulation. This makes the proposed coding structure very attractive for future radio commu-nication systems with high throughput requirements.

关键词： turbo codes concatenated codes convolutional codes soft input soft output (SISO)

New concurrent digital signature scheme based on the computational Diffie-Hellman problem

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The Journal of china Universities of Posts and Telecommunications 2010年第6期17卷 89-94,100页

作者： QIN Wen,ZHOU Nan-run Department of Electronic Information engineering,nanchang {2.,nanchang 330031,china [a] Department of Electronic Information engineering Nanchang University Nanchang 330031 China

Based on strong designated verifiers signatures,a new fair concurrent signature scheme is proposed. Compared with the previous concurrent signature schemes,even if a keystone must be chosen by the initial signer,the matching signer will easily get the keystone through an extraction algorithm. Due to the property of strong designate verifying,the initial signer couldn＇t make use of the keystone prepared carefully to deceive the matching signer. Then the matching signer is able to participate actively the signature scheme. Besides,there aren＇t bilinear operations in the keystone algorithm to deliver the keystone efficiently. Therefore the efficiency of our signature scheme is also improved.

关键词： designated verifiers signature fairness concurrent signature information security

Point-piezomagnetic Properties of the FeCuNbSiB Alloy Strips

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Journal of Wuhan university of Technology(Materials Science) 2009年第1期24卷 114-118页

作者：朱正吼 school of Materials Sciences and engineering Nanchang University

The piezomagnetic properties of rapidly quenched Fe73.5Cu1Nb3Si13.5B9 alloy strips were investigated in as-quenched state and after annealing for 2.h in vacuum in the temperature range of 100-300 ℃. The impedance of amorphous strips increases with frequency, and sensitively de-creases with stress increasing, especially in the frequency range of 10-100 MHz. The impedance in-creases approximately linearly with frequency below the critical frequency, but begins to decrease non-linearly with frequency above the critical frequency. The higher the point compressive stress is, the smaller the critical frequency will be. The stability of piezomagnetic properties is very excellent. The impedance of amorphous strips after annealing, especially at 300 ℃, decreases very strongly. The impedance and the absolute values of the sensitive degree of couple layers＇ amorphous strips are lower than those of single layer strips.

关键词： piezomagnetic properties amorphous strips impedance

Assessment and improvement of autocorrelation performance of chaotic sequences using a phase space method

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Science china(Information Sciences) 2011年第12期54卷 2667-2679页

作者： CHEN Bin school of Software and Communication engineering,{2. university of Finance and Economy, nanchang 330032. china 1. school of Software and Communication engineering JiangXi University of Finance and Economy Nanchang 330032 China

Chaotic sequences have been widely used as pseudorandom sequences. However, how to judge whether their autocorrelation performance is good remains a problem because we have no simple method for assessing and improving the autocorrelation performance. Using a phase space method, we have discovered that the autocorrelation performance of a chaotic sequence is determined by whether its phase space trajectory is axis symmetrical, and have deduced theorems to describe and solve these problems. This paper presents a simple yet effective method to assess and improve the autocorrelation performance of chaotic sequences. Several simulations are presented to validate the theorems and method.

关键词： chaos autocorrelation pseudorandom sequences phase space

Effect of static magnetic field on activity of immobilized α-amylase

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Chinese Science Bulletin 1997年第2期42卷 127-130页

作者： YAN Liushui, ZHU Yuanbao, HE-Shuang’e and CAO Zhixiang1 Department of Chemical engineering, nanchang Institute of Aeronautical Technology, nanchang 330034, china 2. Department of Chemistry and Chemical engineering, Hunan university, Changsha 410082. china Department of Chemical engineering Nanchang Institute of Aenwututical Techndogy Nanchang China Department of Chemistry and Chemical engineering Hunan University Changsha China

BIOLOGICAL effect of magnetic field is one of the three major subjects of contemporary biomagnetism, and is also the basis of applied biomagnetism. In order to explore magnetic biological effects, the influence of various sorts of magnetic field on many living systems as well as their different constructural levels has been extensively studied. However, only a few studies with in vitro enzyme have been reported, and few researches concerning the influence of magnetic field on immobilized enzyme reactions have been published. This note describes

关键词： static magnetic field immobilized α-amylase enzyme activity oscillatory behaviour.

Rank of loop, constraint degree of path, coupling degree of graph and their application

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Progress in Natural Science:Materials International 2005年第2期15卷 79-85页

作者： YANG Tingli1*, LUO Yufeng2. ZHANG Ce3 and YAO Fanghua1(1. SINOPIC Jinling Petrochemical Corp., Nanjing 2.0037, china 2. Department of Mechanical engineering,{2., nanchang 33002., china 3. Department of Mechanical engineering, Tianjin university, Tianjin 300072. china) SINOPIC Jinling Petrochemical Corp. Nanjing 210037 China. Department of Mechanical engineering Nanchang University Nanchang 330029 China. Department of Mechanical engineering Tiánjin University Tianjin 300072 China

Some new concepts (rank of a loop, degree of freedom of a graph, path unit and ordered path arrangement, constraint degree of path, coupling degree of a graph, basic graph, etc.), formulas, and algorithms, are proposed in this paper. Based on these concepts, a new systematic theory and practical method for the design of topological structure, kinematics and dynamics of mechanical systems is established. Some conjectures and problems needed to be researched are also put forward. The concepts, formulae and algorithms presented in this paper will find wide potential applications.

关键词： rank of loop degree of freedom of graph constraint degree of path coupling degree of graph

Real estate appraisal system based on GIS and BP neural network

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中国有色金属学会会刊：英文版 2011年第S3期21卷 626-630页

作者： LIU Xiao-sheng1, DENG Zhe1, WANG Ting-li2.1. school of Architecture and Survey engineering,{2. university of Science and Technology, Ganzhou 341000, china 2. school of Applied Science,{2. university of Science and Technology, Ganzhou 341000, china [a] school of Architecture and Survey engineering Jiangxi University of Science and Technology Ganzhou 341000 China [b] school of Applied Science Jiangxi University of Science and Technology Ganzhou 341000 China

For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was designed which includes appraisal model, trade case, GIS database and query analysis module. With the help of the L-M algorithm in MATLAB software, BP neural network was improved and the trade cases were trained, then the BP neural network which has already been trained was tested. At the same time, the BP neural and GIS were put together to construct the hedonic price estimate model. The C# and ArcGIS9.3 were used to achieve the system in VS2.08. City basic geographic data and real estate related information were used as the basic data in practice. The results show that the functions of querying, adding and editing the spatial data and attribute data are achieved and also the efficiency and accuracy of real estate are improved, so that the new method of real estate is provided by the system.

关键词： BP neural network GIS hedonic price real estate appraisal

Synthesis of a Novel UV-curable Prepolymer Hexanediol Diglycidyl Ether Diacrylate and Its Cured Film Tensile Property

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Journal of Wuhan university of Technology(Materials Science) 2011年第1期26卷 4-9页

作者：黄笔武 school of Material Science and engineering Nanchang University

A novel UV-curable prepolymer hexanediol diglycidyl ether diacrylate （HDGEA） was synthesized by utilizing hexanediol diglycidyl ether （HDGE） and acrylic acid （AA） as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimal synthetic conditions were that the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90-110 ℃, and the molar ratio of HDGE to AA was 1︰2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-curing initiator was added to the synthesized HDGEA to prepare a kind of UV-curing coating. The mechanical properties of the UV-cured films were determined, giving 31.87 MPa of tensile strength, 871.88 MPa of Young＇s modulus and 6.77% of elongation at tear.

关键词： hexanediol diglycidyl ether diacrylate synthesis acrylic acid UV-curable prepolymer film

The study of adsorption gas sensor based carbon nanotube film

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Science china(Technological Sciences) 2005年第4期48卷 372-384页

作者： LI Xin1, LIU Junhua2.& ZHU Changchun1 1. school of Electronic and Information engineering, Xi’an Jiaotong {2., Xi’an 710049, china 2. school of Electric engineering, Xi’an Jiaotong {2., Xi’an 710049, china 1. school of Electronic and Information engineering Xi’an Jiaotong University 710049 Xi’an China 2. school of Electric engineering Xi’an Jiaotong University 710049 Xi’an China

The study of gas sensitivity of multi-wall carbon nanotubes (MWNTs), which is deposited by low press chemical vapor deposition (LPCVD), is presented. The results show that the pure MWNTs are not sensitive to the gases measured, while the composite film consisting of the MWNTs and silicon dioxide is sensitive to the methane, the hydrogen and the acetylene. The MWNTs and silicon dioxide composite film have the capacitance characteristic because of the formation of Schottky junctions within the MWNTs. The chemistry adsorption of the gas measured on the surface of the MWNTs affects the space discharge area of the Schottky junction, so that the dielectric constant changes with the gas concentration. That is why the gas is sensed.

关键词： gas sensor, carbon nanotubes, low press chemical vapor deposition, scatter.