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A relationship between the nonexistence of generalized bent functions and class groups

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science china Mathematics 2010年第1期53卷 213-222页

作者： LIU FengMei 1,& YUE Qin 21 Department of information Research,College of information engineering,information engineering university,Zhengzhou 450002,china 2 Department of Mathematics,nanjing university of Aeronautics and Astronautics,nanjing 210016,china 1. Department of information Research College of Information Engineering Information Engineering University Zhengzhou 450002 China2. Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A new result on the nonexistence of generalized bent functions is presented by using properties of the decomposition law of primes in cyclotomic fields and properties of solutions of some Diophantine equations. At the same time,a method is given which can be used to simplify the known results. Then we give the bounds and the meaning in algebraic number theory of the parameters in our results.

关键词： generalized bent function integral basis class group genus theory

A Raw Signal Simulator for Bistatic SAR

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Chinese Journal of Aeronautics 2009年第4期22卷 434-443页

作者： Xia Weijie,Zhou Jianjiang College of information science and Technology,nanjing university of Aeronautics and Astronautics,nanjing 210016,china [a]College of information science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article proposes a new efficient raw signal simulator for the bistatic synthetic aperture radar （SAR） based on 2D fast Fourier transform （FFT） to deal with cases of both ideal trajectory and trajectory deviation. It begins with analyzing the geometric configuration and the range history of the bistatic SAR in side-looking and squint modes of ideal trajectory as well as trajectory deviation. Then a detailed and mathematical study is conducted on the equivalence relation of bistatic-to-monostatic applications （BTMA） in the case of ideal trajectory and trajectory deviation. Also a set of formulas are derived for the equivalence relation between bistatic SAR and monostatic SAR on some reasonable assumptions. Therefore, the application of the simulation method based on the 2D FFT for the monostatic SAR can be extended to the case of bistatic SAR. Finally, the simulation results prove the validity of this method. By comparing the efficiency of the proposed method with that of the time domain method, it is shown that the former is a few orders of magnitude higher.

关键词： bistatic synthetic aperture radar raw signal simulation fast Fourier transform

Eutectic Solidification in Al-13.0%Si Alloys with Combined Addition of Strontium and Boron

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Journal of Materials science & Technology 2009年第4期25卷 437-440页

作者： Hengcheng Liao,Ke Ding,Juanjuan Bi,Min Zhang,Huipin Wang and Lei Zhao school of Materials science and engineering,southeast university,nanjing 211198,china Jiangsu Key Laboratory for Advanced Metallic Materials,nanjing 211189,china SE Univ Sch Mat Sci & Engn Nanjing 211198 Peoples R China

The influence of addition of boron （B） on eutectic solidification in a near-eutectic Al-13.0%Si alloy modified with strontium （Sr） was investigated using thermal analysis and macro/microstructure observation. Addition of B in the Sr-modified alloy leads to a considerable increase in nucleation temperature （TN, the minimum temperature prior to recalescence （TM） and growth temperature （To）. In the Sr-modified alloy, nucleation of eutectic might originate at the heterogeneous sites on the mold wall or in the melt near the wall, and eutectic solidification proceeds gradually towards the center, controlled by undercooling of melt. However, with addition of B in the Sr-modified alloy, undercooling required for eutectic nucleation became small, and hence eutectic solidification might occur almost simultaneously within whole casting, controlled by amount of heterogeneous sites. With excessive addition of B in the Sr-modified alloy, nucleation of eutectic grains was explosive within the whole casting and the power of Sr on eutectic solidification was completely poisoned.

关键词： Al-Si alloys Solidification Microstructure Thermal analysis

New concatenated soft decoding of Reed-Solomon codes with lower complexities

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The Journal of china Universities of Posts and Telecommunications 2009年第3期16卷 4-7,23页

作者： BIAN Yin-bing,FENG Guang-zeng school of Telecommunication and information engineering,nanjing university of Posts and Telecommunications,nanjing 210003,china [a]school of Telecommunication and information engineering nanjing university of Posts and Telecommunications nanjing 210003 china

To improve error-correcting performance, an iterative concatenated soft decoding algorithm for Reed-Solomon （RS） codes is presented in this article. This algorithm brings both complexity as well as advantages in performance over presently popular sot~ decoding algorithms. The proposed algorithm consists of two powerful soft decoding techniques, adaptive belief propagation （ABP） and box and match algorithm （BMA）, which are serially concatenated by the accumulated log-likelihood ratio （ALLR）. Simulation results show that, compared with ABP and ABP-BMA algorithms, the proposed algorithm can bring more decoding gains and a better tradeoff between the decoding performance and complexity.

关键词： Reed-Solomon codes soft decoding adaptive belief propagation box and match decoding algorithm LLR accumulation

Polymer-assisted nanoparticulate contrast-enhancing materials

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science china Chemistry 2010年第3期53卷 479-486页

作者： DING Yin1,3,HU Yong2,WU Wei1 & JIANG XiQun1 1Laboratory of Mesoscopic Chemistry and Department of Polymer science and engineering,College of Chemistry & Chemical engineering,nanjing university,nanjing 210093,china 2National Laboratory of Solid State Microstructure,Department of Material science and engineering,nanjing university,nanjing 210093,china 3Key Laboratory of Analytical Chemistry for Life science,Ministry of Education,school of Chemistry and Chemical engineering,nanjing university,nanjing 210093,china 1. Laboratory of Mesoscopic Chemistry and Department of Polymer science and engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing 210093 China3. Key Laboratory of Analytical Chemistry for Life Science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China2. National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing 210093 China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and *** fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of *** photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching *** nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and *** potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this *** modification of inorganic nanoparticles could enhance their biostability in physiological conditions and ability of targeting bioactive molecules.

关键词： contrast agent cell image gold nanoparticles iron oxide nanoparticles carbon nanotubes polymeric-inorganic hybrid nanoparticles

Wavelet estimation of the diffusion coefficient in time dependent diffusion models

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science china Mathematics 2007年第11期50卷 1597-1610页

作者： Ping CHEN~(1,2+) Jin-de WANG~1 1 Department of Mathematics,nanjing university,nanjing 210093,china 2 school of science,nanjing university of science and Technology,nanjing 210094,china Department of Mathematics Nanjing University Nanjing 210093 China school of science Nanjing University of Science Technology Nanjing 210094 China

The estimation problem for diffusion coefficients in diffusion processes has been studied in many papers,where the diffusion coefficient function is assumed to be a 1-dimensional bounded Lipschitzian function of the state or the time *** is no previous work for the nonparametric estimation of time-dependent diffusion models where the diffusion coefficient depends on both the state and the *** paper introduces and studies a wavelet estimation of the time-dependent diffusion coefficient under a more general assumption that the diffusion coefficient is a linear growth Lipschitz *** the properties of martingale,we translate the problems in diffusion into the nonparametric regression setting and give the Lr convergence rate.A strong consistency of the estimate is *** this result one can estimate the time-dependent diffusion coefficient using the same structure of the wavelet estimators under any equivalent probability *** example,in finance,the wavelet estimator is strongly consistent under the market probability measure as well as the risk neutral probability measure.

关键词： wavelet estimation time-dependent diffusion coefficient linear growth condition strong consistency

Predicting the Maintainability of Open Source Software Using Design Metrics

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Wuhan university Journal of Natural sciences 2008年第1期13卷 14-20页

作者： ZHOU Yuming1,2, XU Baowen1,3 1. school of Computer science and engineering, southeast university, nanjing 210096, Jiangsu,china 2. Department of Computing, Hong Kong Polytechnic university, Hong Kong, china 3. Jiangsu Institute of Software Quality, nanjing 210096, Jiangsu,china school of Computer science and engineering Southeast University Nanjing China Department of Computing Hong Kong Polytechnic University Hong Kong China Jiangsu Institute of Software Quality Nanjing China

This paper empirically investigates the relationships between 15 design metrics and maintainability of 148 Java open source software. The results show that size and complexity metrics are strongly related to the maintainability of open source software. However, cohesion and coupling, as currently captured by existing metrics, do not seem to have a significant impact on maintainability. When used together, these metrics can predict system maintainability fairly accurately （mean MREs below 30%）.

关键词： open source: object-oriented maintainability metric prediction regression

Dependence Analysis Based on Dynamic Slicing for Debugging

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 398-404页

作者： Chen Zhen qiang 1, Xu Bao wen 1,2 1 Department of Computer science & engineering, southeast university, nanjing 210096, china 2 State Key Laboratory of Software engineering, Wuhan university, Wuhan 430072, china Department of Computer science & engineering Southeast University Nanjing 210096 China

Dynamic program slicing is an effective technique for narrowing the errors to the relevant parts of a program when debugging. Given a slicing criterion, the dynamic slice contains only those statements that actually affect the variables in the slicing criterion. This paper proposes a dynamic slicing method based on static dependence analysis. It uses the program dependence graph and other static information to reduce the information needed to be traced during program execution. Thus, the efficiency is dramatically improved while the precision is not depressed. The slicing criterion is modified to fit for debugging. It consists of file name and the line number at which the statement is.

关键词： program slice slicing criterion program dependence graph

Silicon-based microelectrode arrays for stimulation and signal recording of in vitro cultured neurons

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science china(information sciences) 2011年第10期54卷 2199-2208页

作者： PAN HaiXian 1,L XiaoYing 1 ,WANG ZhiGong 2,REN TianLing 3,FANG Tao 1,ZHANG Jie 1,ZHOU ChangJian 3 & WANG LiGang 3 1 State Key Laboratory of Bioelectronics,southeast university,nanjing 210096,china 2 Institute of RF-& OE-ICs,southeast university,nanjing 210096,china 3 Institute of Microelectronics,Tsinghua university,Beijing 100084,china 1. State Key Laboratory of Bioelectronics Southeast University Nanjing 210096 China2. Institute of RF-& OE-ICs Southeast University Nanjing 210096 China3. Institute of Microelectronics Tsinghua University Beijing 100084 China

Microelectrode arrays (MEAs) for stimulation and signal recording of in vitro cultured neurons are *** MEA is composed of 60 independent electrodes with 59 working ones and one reference *** electrodes are divided into 30 *** each pair of electrodes,four independent states can be realized to define the accessing modes of neurons cultured on the surface of the electrodes.A total MEA covers an area of 10 mm×10 *** are fabricated in a silicon-based semiconductor *** implemented MEA is bonded on a specially designed printed-circuit-board (PCB) and surrounded by a culture *** impedance measurement has been made to verify the electrical characteristics of *** surface was modified to enhance the biocompatibility.A series of PC12 cells culture experiments validates the effectiveness of the *** extracellular signal recording experiment with acetylcholine (Ach) as a stimulant has been carried out,and the results show the feasibility of MEAs for extracellular action potential *** electrical stimulation and recording experiments have been carried out *** indicate that MEAs can be used for extracellular stimulation,recording,simultaneous stimulation and recording,and isolation of PC12 cells network cultured in vitro.

关键词： microelectrode arrays (MEAs) extracellular recording stimulation and recording neurons net-work in vitro