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Denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

science china Earth sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2, CHEN Zhenlou1,3. XU Shiyuan1,2, HU Lingzhen1 & WANG Jun1,2 1. College of Resources & Environment, East china Normal University, Shanghai 200062, china 2. State Key laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, East china Normal University, Shanghai 200062, china 3. Key laboratory of Geographical information science of Ministry of Education,East china Normal University,Shanghai 200062, china 1. College of Resources & Environment East China Normal University Shanghai 200062 China 2. State Key laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai 200062 China 3. Key laboratory of Geographical information science of Ministry of Education East China Normal University Shanghai 200062 China

From July 2003.to July 2004, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2O) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2O source of the water. Sediment N2O natural production rate was between -0.08 and 1.74 μmolN·m-2·h-1. N2O natural production rate was higher in the summer. The difference of the N2O natural production rate in the different tidal flats, the correlation between the N2O natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2O production, while in the low tidal flat sediment, the production of the N2O came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12 to 3..3. μmolN·m-2·h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

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Human knowledge acquisition from 3. interaction in virtual environments

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science china(information sciences) 2012年第7期55卷 1528-1540页

作者： CHENG Cheng,JIANG Ru & DONG XueMei Beijing laboratory of Intelligent information technology,School of Computer {3.,Beijing Institute of technology,Beijing 100081,china 1. Beijing laboratory of Intelligent information technology School of Computer Science Beijing Institute of Technology Beijing 100081 China

Recently,virtual environment (VE) based design and planning,which is a kind of interaction intensive computing,has shown great *** users of such systems are specialists or technicians and their 3. interactions with the system embed a great deal of knowledge and ***,how to integrate human knowledge and skills into VE is a great challenge to researchers in the human computer interaction *** paper proposes a method for acquiring user knowledge from *** main ideas and work include,abstracting the interactive process and formalizing the interactive semantics,as well as providing a semantic model of an interactive information repository,from which user interactive processes can be retrieved and all kinds of application logics can be established.A virtual assembly planning system is introduced as an example of a practical application of this *** show that the related models can well capture user knowledge and retrieve the interaction process.

关键词： human computer interaction interactive semantics virtual environment temporal logic virtual manufacturing virtual assembly

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A variational method for contour tracking via covariance matching

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science china(information sciences) 2012年第11期55卷 2635-2645页

作者： WU YuWei,MA Bo & LI Pei Beijing laboratory of Intelligent information technology,School of Computer {3.,Beijing Institute of technology,Beijing 100081,china 1. Beijing laboratory of Intelligent information technology School of Computer Science Beijing Institute of Technology Beijing 100081 China

This paper presents a novel formulation for contour *** model the second-order statistics of image regions and perform covariance matching under the variational level set ***,covariance matrix is adopted as a visual object representation for partial differential equation(PDE) based contour ***-Euclidean calculus is used as a covariance distance metric instead of Euclidean distance which is unsuitable for measuring the similarities between covariance matrices,because the matrices typically lie on a non-Euclidean manifold.A novel image energy functional is formulated by minimizing the distance metric between the candidate object region and a given template,and maximizing the one between the background region and the *** corresponding gradient flow is then derived according to a variational approach,enabling partial differential equations(PDEs) based contour *** on several challenging sequences prove the validity of the proposed method.

关键词： contour tracking covariance region descriptor level set Log-Euclidean Riemannian metric

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A new DSmT combination rule in open frame of discernment and its application

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science china(information sciences) 2012年第3期55卷 551-557页

作者： WEN ChengLin1, XU XiaoBin1,2 , JIANG HaiNa1 & ZHOU Zhe1 1School of Automation, Hangzhou DianZi University, Hangzhou 3.0018, china 2Department of Automation and tsinghua national {3. for information science and technology, tsinghua University, Beijing 100049, china 1. School of Automation Hangzhou DianZi University Hangzhou 310018 China2. Department of Automation and Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100049 China

A new combination rule based on Dezert-Smarandache theory (DSmT) is proposed to deal with the conflict evidence resulting from the non-exhaustivity of the discernment frame. A two-dimensional measure factor in Dempster-Shafer theory (DST) is extended to DSmT to judge the conflict degree between evidence. The original DSmT combination rule or new DSmT combination rule can be selected for fusion according to this degree. Finally, some examples in simultaneous fault diagnosis of motor rotor are given to illustrate the effectiveness of the proposed combination rule.

关键词： DSmT rule of combination open frame of discernment evidence conflict simultaneous faults diagnosis generalized basic probability assignment

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A policy-based automated negotiation for privileges in grid environments

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Journal of Pharmaceutical Analysis 2009年第1期21卷 11-16页

作者： Run-lian Zhang1,2, Xiao-nian Wu2,3. Xiao-she Dong11.School of Electronic & information Engineering, Xi’an Jiaotong University, Xi’an 710049, china 2.School of information and Communication, Guilin University of Electronic {3., Guilin 541004, china 3.national laboratory for Modern Communications, Chengdu 610041, china. School of Electronic and information Engineering Xi'an Jiaotong University Xi'an 710049 China School of information anf Communication Guilin University of Electronic Technology Guilin 541004 China national laboratory of Modern Communications Chengdu 610041 China

To maintain the global consistency of the authorizing is a challenge when the system authorization is changed in grid environments. This paper proposes a policy-based automatically negotiating method to deal with this issue. An effective system framework, which includes the certificate management, the access policy repertory, the negotiator and the automatically negotiating mechanism, is designed and implemented. The experimental results show that automated negotiation can quickly regain the global authorization consistency and only cause a little system overhead increasing. Compared with the manual authorization maintaining, the presented method can reduce the negotiating time significantly, and reduce the meaningless grid jobs because the inconsistent privileges are controlled timely.

关键词： grid security authorization policy negotiation

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A new one-bit diFFerence collision attack on HAVAL-128

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science china(information sciences) 2012年第11期55卷 2521-2529页

作者： ZHANG WenYing1,2,3.LI YanYan1 & WU Lei1 1School of information science and Engineering,Shandong Normal University,Jinan 250014,china 2State Key Lab of information Security,Institute of information Engineering,Chinese Academy of sciences,Beijing 100093.china 3.handong Provincial Key laboratory for Novel Distributed Computer Software technology,Jinan 250014,china 1. School of information science and Engineering Shandong Normal University Jinan 250014 China2. State Key Lab of Information Security Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China3. Shandong Provincial Key Laboratory for Novel Distributed Computer Software Technology Jinan 250014 China

In this paper,we give a new fast attack on *** attack includes many present methods of constructing hash ***,we present a neighborhood *** propose a new difference path different from the previous *** conclusion is that,when the output of each step satisfies our condition,the message m can collide with m'= m + Δm,where Δm =(0,0,0,0,23.,0,...,0).There is only one bit difference between m and m'.Two pairs of collision examples for HAVAL-128 are *** order to improve the probability of collision,we use four tricks of message *** attack's running time is less than 225.83.2-pass HAVAL computations,which is the best result for one-bit collision of HAVAL so far.

关键词： cryptography hash function HAVAL-128 collision message modification

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The band structures of BSb and B_xGa_(1-x)Sb alloys

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science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 843-847页

作者： XIONG DePing1, ZHOU ShouLi2, WANG Qi3. LUO Li1, HUANG YongQing3.& REN XiaoMin3.1 School of Physics and Optoelectronic Engineering, Guangdong University of technology, Guangzhou 510006, china 2 College of information Engineering, Zhejiang University of technology, Hangzhou 3.003., china 3.Key laboratory of Optical Communication and Lightwave Technologies Ministry of Education, Beijing University of Posts and Telecommunications, Beijing 100876, china 1. School of Physics and Optoelectronic Engineering Guangdong University of Technology Guangzhou 510006 China 2. College of information Engineering Zhejiang University of Technology Hangzhou 310032 China 3. Key laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The band structures of BSb and BxGa1-xSb alloys are studied using first-principles calculations in the generalized gradient approximation. By SQS-8 supercells to model a random alloy, the direct transition energy-gap (Γ15v- Γ1c) bowing of 3.0 eV is obtained for BxGa1-xSb alloys in x = 0-50%, in x = 0-11% the energy-gap is the band-gap and increases by 7 meV/%B with boron composition increasing; by SQS-16 supercells the bowing parameter is about 1.9 eV in x = 0-12.5%. The formation enthalpies of mixing, ΔH, are calculated for BxGa1-xAs and BxGa1-xSb alloys. A comparison of enthalpies indicates that BxGa1-xSb films with boron composition of 7% may be possible.

关键词： band-gap bowing parameter boride alloys

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Predistortion of high speed optical OFDM signal for aliasing-free receiving in multiple low-bandwidth receiver system

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Chinese Optics Letters 2010年第4期8卷 377-380页

作者：程林闻和郑小平张汉一郭奕理 State Key laboratory on Integrated Optoelectronics/tsinghua national laboratory for information science and technology Department of Electronic EngineeringTsinghua University

A cost-effective method of multi-receiver optical orthogonal frequency-division multiplexing（OOFDM） system is proposed to reduce the requirement for the speed of the receiver and the size of fast Fourier transform（FFT）.The sampling rate of analog-to-digital converters（ADCs） can be reduced to 1/N of the original signal bandwidth in an N-receiver *** by signal predistortion at the transmitter, aliasing-free signal can be retrieved independently and directly at the low speed receivers.A back-to-back experimental result is given for a two-receiver *** effect of the electrical filters added before the ADC is studied and the analysis for filters optimization is given.

关键词： Cost reduction Fast Fourier transforms Orthogonal frequency division multiplexing

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Multi-spectral image fusion method based on two channels non-separable wavelets

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science in china(Series F) 2008年第12期51卷 2022-2032页

作者： LIU Bin1,2 & PENG JiaXiong3.1 School of Mathematics and Computer science, Hubei University, Wuhan 43.062, china 2 Key laboratory of Applied Mathematics of Hubei Province, Wuhan 43.062, china 3.Institute of Image Recognition and Artificial Intelligence, Huazhong University of science and technology, Wuhan 43.074, china 1. School of Mathematics and Computer science Hubei University Wuhan 430062 China 2. Key laboratory of Applied Mathematics of Hubei Province Wuhan 430062 China 3. Institute of Image Recognition and Artificial Intelligence Huazhong University of Science and Technology Wuhan 430074 China

A construction method of two channels non-separable wavelets filter bank which dilation matrix is [1, 1; 1,-1] and its application in the fusion of multi-spectral image are presented. Many 4×4 filter banks are designed. The multi-spectral image fusion algorithm based on this kind of wavelet is proposed. Using this filter bank, multi-resolution wavelet decomposition of the intensity of multi-spectral image and panchromatic image is performed, and the two low-frequency components of the intensity and the panchromatic image are merged by using a tradeoff parameter. The experiment results show that this method is good in the preservation of spectral quality and high spatial resolution information. Its performance in preserving spectral quality and high spatial information is better than the fusion method based on DWFT and IHS. When the parameter t is closed to 1, the fused image can obtain rich spectral information from the original MS image. The amount of computation reduced to only half of the fusion method based on four channels wavelet transform.

关键词： image fusion non-separable wavelets multi-spectral image panchromatic image

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Configural processing of different topologically structured figures:an ERP Study

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science china(Life sciences) 2009年第12期52卷 1198-1204页

作者： ZHANG JunJun1, ZHU WeiNa2,3.4, DING XiaoJun1, ZHOU ChangLe1, HU XinTian2,3.& MA YuanYe2,3. 1 Lab of Mind, Art and Computation, Xiamen University, Xiamen 3.1005, china 2 Kunming Institute of Zoology, Chinese Academy of sciences, Kunming 650223. china 3.State Key {3. of Brain and Cognitive science, Institute of Biophysics, Chinese Academy of sciences, Beijing 1001001, china 4 School of information science, Yunnan University, Kunming 650223. china 1. Lab of Mind Art and Computation Xiamen University Xiamen 361005 China 2. Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China 3. State Key laboratory of Brain and Cognitive science Institute of Biophysics Chinese Academy of Sciences Beijing 1001001 China 4. School of information science Yunnan University Kunming 650223 China

According to Chen's theory, topological differences are perceived faster than feature differences in early visual perception. We hypothesized that topological perception is caused by the sensitivity in discriminating figures with and without "holes" . An ERP experiment was conducted utilizing a passive paradigm to investigate the differences in perceiving figures with "hole" and with "no-hole" . The results showed differences in N170 components between figures with "holes" and with "no-holes" . The inversion of the "hole" could influence the latency of N170, but the inversion of the "no-hole" could not, which indicated that global features are processed first in the "hole" perception whilst local features are given priority to the "no-hole" perception. This result was similar to studies concerning face and non-face objects, suggesting a configural processing of the "hole" .

关键词： visual evoked potential topological perception N170

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