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An integrated quantum secure communication system

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Science china(Information Sciences) 2011年第12期54卷 2598-2611页

作者： DAI WenChao, LU Yuan, ZHU Jun & ZENG GuiHua State Key Lab of Advanced Optical Communication Systems and Networks, department of Electronic Engineering shanghai jiaotong university, {2. 2.02.0, china 1. State Key Lab of Advanced Optical Communication Systems and Networks Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China

In this paper, we investigate experimentally an integrated quantum secure communication system using weak coherent state. Two modules are involved in the presented system. One is used for generating the secret key which is obtained using continuous variable quantum key distribution scheme, and the other serves to encrypt and decrypt the real-time private data using a pure quantum cryptographic algorithm. The sifted key rate with reverse reconciliation is 8.6 and 3.9 kb/s in the quantum key distribution scheme under the individual attack and the collective attack, respectively. The system uses an all-fiber dual unbalance beam Mach-Zehnder interferometer, and is implemented with a 500 kb/s modulation rate over 2..2.km of optical fiber.

关键词： quantum key distribution quantum stream encryption integrated system

Hardening of Thermal Photons Through Inverse Compton Scattering in Strong Magnetic Fields

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Chinese Journal of Astronomy and Astrophysics 2001年第5期1卷 411-420页

作者： YiXu Hong－HuaXu departmentofphysics ShanghaiJiaotongUniversityShanghai200030 departmentofphysics ShanghaiJiaotongUni

A new spectrum function is obtained by use of the Compton scattering cross section in the laboratory frame derived earlier. This spectrum function, besides some modifications in the coefficients of the resonant term, contains also a non-resonant term which is inversely proportional to the square of the magnetic field. Based on this spectrum function, the hardening of thermal photons through inverse Compton scattering by relativistic electron beams on the surface of a strongly magnetized neutron star is investigated. Two new features are found. First, there is a maximum scattered photon energy for a given resonant scattering, beyond which resonance disappears. This maximum depends on the electron energy and the magnetic field, but is independent of the incident photon energy. Second, beyond each resonant scattering, there is a high-energy tail, resulting from non-resonant scattering. It is also found that all the tails have a common upper limit which is the highest scattered photon energy for the given incident photon and electron energies. These two new features are absent in the Monte Carlo simulations and therefore, may have physical implications for y-ray emissions.

关键词： stars: neutron star magnetic fields - scattering - gamma rays

Object Tracking and Tracing:Hidden Semi-Markov Model Based Probabilistic Location Determination

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Journal of shanghai jiaotong university(Science) 2011年第4期16卷 466-473页

作者：吴捷王东盛焕烨 department of Computer Science and Engineering Shanghai Jiaotong University

The enhancement of radio frequency identification(RFID) technology to track and trace objects has attracted a lot of attention from the healthcare and the supply chain ***,RFID systems do not always function reliably under complex and variable deployment *** many cases,RFID systems provide only probabilistic observations of object ***,an approach to predict,record and track real world object states based upon probabilistic RFID observations is *** Markov model(HMM) has been used in the field of probabilistic location *** the inherent duration probability density of a state in HMM is exponential,which may be inappropriate for modeling of object location ***,in this paper,we put forward a hidden semi-Markov model(HSMM) based approach for probabilistic location determination. We evaluated its performance comparing with that of the HMM-based *** results show that the HSMM-based approach provides a more accurate determination of real world object states based on observation data.

关键词： object tracking and tracing hidden semi-Markov model(HSMM) probabilistic location determination radio frequency identification(RFID)

Endoscopic sphincterotomy associated cholangitis in patients receiving proximal biliary self-expanding metal stents

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Hepatobiliary & Pancreatic Diseases International 2012年第6期11卷 643-649页

作者： Hui Zhou, Lei Li, Feng Zhu, Sheng-Zheng Luo, Xiao-Bo Cai,Xin-Jian Wan department of Gastroenterology, shanghai First People’s Hospital,{2., shanghai 2.0080, china department of Gastroenterology Shanghai First People's Hospital Shanghai Jiaotong University Shanghai 200080 China

BACKGROUND: Endoscopic biliary stent placement during the procedure of endoscopic retrograde cholangiopancreatography (ERCP) is preferred to provide biliary drainage for unresectable malignant biliary obstruction. There is considerable controversy over the use of endoscopic sphincterotomy (ES) prior to stent placement. This study aimed to determine whether ES before intraductal self-expanding metal stent (SEMS) placement affects the clinical outcome and complications in patients with proximal malignant obstructive biliary diseases. METHODS: In a prospective randomized controlled trial, 82.patients with inoperable malignant biliary strictures were randomly assigned to biliary stenting groups with or without ES. Resolution of jaundice and the incidence of complications including acute cholangitis, pancreatitis and stent occlusion within 6 months were evaluated. RESULTS: SEMSs were successfully deployed in all patients, resulting in clinical and biochemical improvement of obstructive symptoms in both groups. The incidence of cholangitis was higher in the ES group than in the non-ES group (58.5% vs 31.7%, P=0.015). The interval between stent placement and the first acute cholangitis was much shorter in the ES group than in the non-ES group (P=0.02.). The use of ES increased the incidence of cholangitis (P=0.004, risk ratio, 8.196). The rate of post-ERCP pancreatitis after stent placement was greater in the non-ES group than in the ES group (31.7% vs 9.8%, P=0.014). No significant differences were found in the rate of restenosis and the mortality rate between the two ***: ES prior to intraductal SEMS placement was associated with an increased incidence of acute cholangitis. ES should be carefully evaluated prior to its use in patients with proximal malignant obstructive biliary diseases.

关键词： sphincterotomy biliary obstructions endoscopic retrograde cholangiopancreatography cholangitis pancreatitis

Chemical Extraction Preparation of Delithiated Cathode Materials of Li-ion Battery

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Journal of Wuhan university of Technology(Materials Science) 2009年第6期24卷 863-866页

作者：闫时建 School of Materials Science and Engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2.2.8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

TFEL of Ce^(3+) in zine sulpho-oxide

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Chinese Science Bulletin 1998年第14期43卷 1179-1183页

作者： YU Lei\+1, LOU Zhidong\+1, XU Chunxiang\+1, XU Zheng\+2.and XU Xurong\+2.1. Institute of Material physics, Tianjin Institute of Technology, Tianjin 300191, china {2., Northern jiaotong university, Beijing 100044, china Institute of Material physics Tianjin Institute of Technology Tianjin China department of physics Northern Jiaotong University Beijing China

A new TFEL material ZnS X O 1-X : Ce 3+ is prepared. The EL brightness of ZnS X O 1-X : Ce 3+ is at least one order higher than that of ZnS: Ce 3+ at the same doping concentration of Ce 3+ . The EL emission wavelength of ZnS X O 1-X : Ce 3+ (\%X\%=0.5) ranges from 400 to 600 nm. The emission of ZnS X O 1-X : Ce 3+ may be used as the blue part of white TFEL.

关键词： thin_film electroluminescence (TFEL) filter layered optimization zine sulpho_oxide.

Classification and Functional Separable Solutions to Extended Nonlinear Wave Equations

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Communications in Theoretical physics 2005年第10期44卷 589-596页

作者： ZHANG Shun--Li LOU Sen--Yue QU Chang--Zheng YUE Rui--Hong Institute of Modern physics, Northwest university, Xi'an 710069,{2. department of Mathematics, Northwest university, Xi'an 710069,{2. Center of Nonlinear Science, Ningbo university, Ningbo 3152.1,{2. department of physics, shanghai Jiao Tong university,{12.,{2. Institute of Modern physics Northwest University department of Mathematics Northwest University Center of Nonlinear Science Ningbo University department of physics Shanghai Jiao Tong University

The generalized conditional Symmetry approach is applied to study the variable separation of the extendedwave equations. Complete classification of those equations admitting functional separable solutions is obtained ... 详细信息

关键词： nonlinear wave equations functional separable solutions generalized conditional symmetry

Stability of Solution of a Class of Quasilinear Elliptic Equations

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Acta Mathematicae Applicatae Sinica 2002年第3期18卷 461-470页

作者： Qi-kang Ran, Ai-nong Fangdepartment of Applied Mathematics, shanghai {2. of Finance and Economics, shanghai 2.0433, chinadepartment of Applied Mathematics, shanghai jiaotong university, shanghai 2.0030, china department of Applied Mathematics Shanghai University of Finance and Economics Shanghai China department of Applied Mathematics Shanghai Jiaotong University Shanghai China

In this paper, using capacity theory and extension theorem of Lipschitz functions we first discuss the uniqueness of weak solution of nonhomogeneous quasilinear elliptic equationsin space W(θ,p)(Ω), which is bigger than W1,p(Ω). Next, using revise reverse Holder inequality we prove that if ωc is uniformly p-think, then there exists a neighborhood U of p, such that for all t ∈U, the weak solutions of equation corresponding t are bounded uniformly. Finally, we get the stability of weak solutions on exponent p.

关键词： Nonhoraogeneous quasilinear elliptic equations capacity stability

Resting state brain activity and functional brain mapping

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Progress in Natural Science:Materials International 2007年第5期17卷 511-519页

作者： Zhao Xiaohu , Wang Peijun and Tang Xiaowei (College of life Sciences in Zhejiang university, Hangzhou 310058, china Imaging {2. of Tong Ji Hospital of Tong Ji university, shanghai 2.0065, china Bio-X Lab, {2. of physics, Zhejiang university, Hangzhou 31002., china) [a]College of life Sciences in Zhejiang university Hangzhou China [b]Imaging department of Tong Ji Hospital of Tong Ji university Shanghai China [c]Bio-X Lab Department of Physics Zhejiang University Hangzhou China

Functional brain imaging studies commonly use either resting or passive task states as their control conditions, and typically identify the activation brain region associated with a specific task by subtracting the resting from the active task conditions. Numerous studies now suggest, however, that the resting state may not reflect true mental "rest" conditions. The mental activity that occurs during "rest" might therefore greatly influence the functional neuroimaging observations that are collected through the usual subtracting analysis strategies. Exploring the ongoing mental processes that occur during resting conditions is thus of particular importance for deciphering functional brain mapping results and obtaining a more comprehensive understanding of human brain functions. In this review article, we will mainly focus on the discussion of the current research background of functional brain mapping at resting state and the physiological significance of the available neuroimaging data.

关键词： resting state brain activity default mode brain networks BOLD deactivation OEF.