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Science in china(Series f) 2008年第11期51卷 1871-1882页

作者： zhang hong1,2,DUAN haix.n1,3.& LIU Wu1,3.1 Tsinghua {3. laboratory for Information Science and Technology,Tsinghua university,beijing 100084,china 2 department of Computer Science and Technology,Tsinghua university,beijing 100084,china 3.Network Research center,Tsinghua university,beijing 100084,china Tsinghua national laboratory for Information Science and Technology Tsinghua University department of Computer Science and Technology Tsinghua University Network Research center Tsinghua University

Reputation systems represent soft security mechanisms that complement traditional information security mechanisms. They are now widely used in online e-commerce markets and communities in order to stimulate good behaviors as well as to restrain adverse behaviors. This paper analyzes the limitations of the conversational reputation models and proposes an incentive reputation model called the resilient reputation model （RRM） for the distributed reputation systems. The objective of this reputation model is not only to encourage the users to provide good services and, therefore, to max.mize the probability of good transaction outcomes, but also to punish those adverse users who are trying to manipulate the application systems. The simulation results indicate that the proposed reputation model （RRM） could effectively resist against the common adverse behaviors, while protecting the profits of sincere users from being blemished by those adversaries.

关键词： reputation model distributed system trust soft security

Anomalous magnetotransport in LaMn_(1-x.Te_x._3

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2, ChEN Zhenghao3.& zhang x.aoZhong4,5 1 Key laboratory of Beam Technology & Materials Modification of the Ministry of Education, Institute of Low Energy Nuclear Physics,{3. Normal university,{3. 100875, china 2{3. Radiation center,{3. 100875, china 3.laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences,{3. 100080, china 4 Key laboratory of Advanced Materials of the Ministry of Education, department of Materials Science and Engineering, Tsinghua university,{3. 100084, china 5{3. national center for Electron Microscopy, Tsinghua university,{3. 100084, china Key laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation center Beijing China laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing China Key laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing China beijing national center for Electron Microscopy Tsinghua University Beijing China

The LaMn1-x.ex.3.δ (x.0.1, 0.2, 0.3. were synthesized using solid-state reaction method for the first time. x.ray photoemission spectrum (x.S) shows that in the samples the Te ions have a valence of Te4+, and Mn3. ions are partly converted into Mn2+ and Mn4+ due to the ex.ess ox.gen and Te doping. The magnetotransport associated with Mn2+, Mn3. and Mn4+ was investigated. The ex.erimental results show that the samples are insulator at 0 T when the amount of Mn3. is much larger or less than the sum of Mn2+ and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3. is close to the sum of Mn2+ and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-ex.hange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

Absolute radiometric calibration of CBERS-02 IRMSS thermal band

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Science china(Technological Sciences) 2005年第S2期48卷 72-90页

作者： zhang Yong1,2,3. GU x.ngfa1,3.4, YU Tao1,3. zhang Yux.ang5, ChEN Liangfu1,3. LI x.aoying1,2,3. LI x.aowen1,3.& hE Liming6 1. State Key laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal university, beijing 100101, china 2. Graduate university of Chinese Academy of Sciences, beijing 10003., china 3. The center for national Spaceborne Demonstration, beijing 100101, china 4. Institut national de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, france 5. national Satellite meteorological center, beijing 100081, china 6. State Environmental Protection Administration, beijing 100029, china State Key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Graduate university of Chinese Academy of Sciences The center for national Spa

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2004 are carried out in this research. When making onboard blackbody calibration of CBERS-02 IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field ex.eriments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02 IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2004 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02 IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53.(gain, unit: DN/W m?2sr?1μm?1) and 44.92 (offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

Chinese Ex.ert Consensus on the Diagnosis and Treatment of Adult Dermatomyositis (2022)#

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International Journal of Dermatology and Venereology 2024年第3期7卷 163-173页

作者： Cao h. Chen A.-J. cui Y. Deng D.-Q. gao x.-h. he Y.-L. Kang x.-J. Jin h.-Z. Li C.-x. Li f. Li h.-J. Liao W.-J. Liu x.-M. Lu Q.-J. Lu Y. Pan M. Pan W.-h. Shu x.-M. Sun Q. Tang K.-Y. Tao J. Wang Y. x.ao T. zhang f.-R. zhang h.-L. department of Dermatology Ruijin Hospital Affiliated Shanghai Jiao Tong University School of Medicine Shanghai 200025 China department of Dermatology First Affiliated Hospital of Chongqing Medical University Chongqing 400042 China department of Dermatology China-Japan Friendship Hospital Beijing 100029 China department of Dermatology The Second Affiliated Hospital of Kunming Medical University Yunnan Kunming 650101 China department of Dermatology The First Hospital of China Medical University Liaoning Shenyang 110001 China department of Dermatology Beijing Chaoyang Hospital Affiliated to Capital Medical University Beijing 100020 China department of Dermatology and Venereology People's Hospital of Xinjiang Uygur Autonomous Region Xinjiang Uygur Autonomous Region Urumqi 830001 China department of Dermatology State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College Hospital Chinese Academy of Medical Science Peking Union Medical College Beijing 100730 China department of Dermatology First Medical Center PLA General Hospital Beijing 100853 China department of Dermatology Hainan Hospital of PLA General Hospital Hainan Sanya 572013 China department of Dermatology Xijing Hospital Air Force Medical University Shaanxi Xi'an 710032 China department of Dermatology Huazhong University of Science and Technology Union Shenzhen Hospital Guangdong Shenzhen 518052 China hospital for Skin Diseases Institute of Dermatology Chinese Academy of Medical Sciences Peking Union Medical College Jiangsu Nanjing 210042 China department of Dermatology Jiangsu Province Hospital The First Affiliated Hospital Nanjing Medical University Jiangsu Nanjing 210029 China department of Dermatology Shanghai Changzheng Hospital Second Affiliated Hospital of Naval Medical University Shanghai 200003 China department of Rheumatology China-Japan Friendship Hospital Beijing 100029 China department of Dermatology Qilu Hospital of Shandong Universit

Dermatomyositis, an idiopathic inflammatory myopathy, is characterized by distinctive skin manifestations, prox.mal muscle weakness, and multiple organ involvement and can be accompanied by malignancies. To provide a reference for dermatologists and clinicians in other relevant fields of clinical practice, ex.erts from the Dermatology Branch of the china Inter{3. Ex.hange and Promotion Association for Medical and health Care and the {3. Clinical Research center for Dermatologic and Immunologic Diseases developed this consensus on the diagnosis and treatment of adult dermatomyositis using Chinese and inter{3. literature and ex.ert advice. © 2024 Wolters Kluwer health. All rights reserved.

关键词： adult clinical protocols dermatomyositis diagnosis ex.ert consensus treatment

Synchronous estimation of DTM and fractional vegetation cover in forested area from airborne LIDAR height and intensity data

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Science china(Technological Sciences) 2008年第S2期51卷 176-187页

作者： BAO Yunfei1,2,CAO Chunx.ang1,zhang hao1,ChEN Erx.e3.hE QiSheng1,2,hUANG huaBing1,LI ZengYuan3.LI x.aoWen1,4 & GONG Peng1 1 State Key laboratory of Remote Sensing Science,jointly sponsored by the Institute for Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal university,beijing 100101,china 2 Graduate university of the Chinese Academy of Sciences,beijing 100049,china 3.Institute of forest Resource Information Technique,the Chinese Academy of forestry,beijing 100091,china 4 Research center for Remote Sensing and GIS,department of geography and beijing Key laboratory for Remote Sensing of Environment and Digital Sites,beijing Normal university,beijing 100875,china State Key laboratory of Remote Sensing Science jointly sponsored by the Institute for Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate university of the Chinese Academy of Sciences Beijing China Institute of forest Resource Information Technique the Chinese Academy of Forestry Beijing China Research center for Remote Sensing and GIS Department of Geography and Beijing Key Laboratory for Remote Sensing of Environment and Digital Sites Beijing Normal University Beijing China

We proposed a method to separate ground points and vegetation points from discrete return,small footprint airborne laser scanner data,called skewness change *** method,which makes use of intensity of laser scanner data,is especially applicable in steep,and forested *** does not take slope of forested area into account,while other algorithms consider the change of slope in steep forested *** ground points and vegetation points can be used to estimate digital terrain model(DTM) and fractional vegetation cover,respectively.A few vegetation points which were classified into the ground points were removed as noise before the generation of *** method was tested in a test area of 10000 square meters.A LiteMapper -5600 laser system was used and a flight was carried out over a ground of 700―800 *** this tested area,a total number of 1546 field measurement ground points were measured with a total station TOPCON GTS-602 and TOPCON GTS -7002 for validation of DTM and the mean error value is -18.5 cm and the RMSE(root mean square error) is ±20.9 cm.A data trap sizes of 4m in diameter from airborne laser scanner data was selected to compute vegetation fraction *** of fractional vegetation cover was carried out using 15 hemispherical photographs,which are georeferenced to centimeter accuracy by differential *** gap fraction was computed over a range of zenith angles 10° using the gap light analyzer(GLA) from each hemispherical *** R2 for the regression of fractional vegetation cover from these ALS data and the respective field measurements is *** this study presents a method for synchronous estimation of DTM and fractional vegetation cover in forested area from airborne LIDAR height and intensity data.

关键词： LIDAR intensity skewness synchronous DTM fractional vegetation cover

The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2,4, zhang Qingyun1, TAO Shiyan1 & JU Jianhua3.1. State Key laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences,{3. 100029, china 2. department of Atmospheric Sciences, Yunnan university, Kunming 650091, china 3. china meteorological Administration Training Centre,{3. 100081, china 4. Graduate School of Chinese Academy of Sciences,{3. 10003., china State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China department of Atmospheric Sciences Yunnan University Kunming 650091 China Graduate School of Chinese Academy of Sciences Beijing 100039 China china meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from national Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction center’s merged analysis of pre- cipitation (cmaP) data and the national centers for Environmental Prediction/national center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South china Sea and the Indian subcontinent are ex.lored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2nd pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

A new family of windows——convolution windows and their applications

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Science china(Technological Sciences) 2005年第4期48卷 468-480页

作者： zhang Jieqiu1,2, LIANG Changhong1 & ChEN Yanpu3.1. department of Applied Math. & Phys., College of Science, Airforce Engineering {3., x.’an 710051, china 2. national Key laboratory of Antennas and Microwave Technology, x.dian {3., x.’an 710071, china 3. Computer center, x.’an Communication College, x.’an 710106, china department of Applied Math. & Phys. College of Science Airforce Engineering University national Key laboratory of Antennas and Microwave Technology Xidian University Computer center Xi"an Communication College

A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The ex.ressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approx.mately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time.

关键词： signal processing harmonic analysis window function convolution window synchronous error spoctral leakage

Implantable CMOS neuro-stimulus chip for visual prosthesis

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Science china(Information Sciences) 2011年第4期54卷 898-908页

作者： zhang x. 1,PEI Weihua 1,hUANG BeiJu 1,WANG ShuJing 1,GUAN Ning 1,GUO Kai 1,WANG Yu 1,GUI Qiang 1,ChEN Jin 1,WANG Kai 2,WU huiJuan 2,LI x.aox.n 2,LI Kai 3.& ChEN hongDa 1 1 State Key laboratory on Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of Sciences,beijing 100083.china 2 department of Ophthalmology,People’s hospital of Peking university,beijing 100044,china 3.department of Epidemiology and Biostatistics,health Science center,Peking university,beijing 100083.china State Key laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences

A prototype chip with 2×2 pix.ls for implanting in blind patients affected by outer retinal degeneration is presented in this *** visual prosthesis chip imitates the degenerated photoreceptor cells,senses the incident light and stimulates the remaining healthy layers of retina or optic *** pix.l integrates photodiode and stimulus pulse generator,converting the illumination on the eyes into 3.bit resolution bi-phasic current ***-chip charge cancellation modules are used to discharge each electrode site for tissue *** prototype chip is designed and fabricated in 0.18-μm N-well CMOS (complementary metal ox.de semiconductor) 1P6M Mix.signal process,with a ±2.5 V dual voltage *** functionality of the fabricated chip is demonstrated on anesthetized *** responses in visual cortex.are successfully evoked by the neuro-stimulus chip through an on-board trigger interface and flex.ble electrode.

关键词： biomedical microelectronics visual prosthesis functional electrical stimulation acute animal ex. periment electrical evoked potential (EEP) test

Observation constraints of the hard x.ray modulation telescope hx.T

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 31-35页

作者： LU Yu1,2,zhang WenZhao3.QU JinLu1,SONG LiMing1,gao Jian3.zhang hongMei4 & OU Ge4 1 Key {3. of Particle Astrophysics,Institute of high Energy Physics,Chinese Academy of Sciences,beijing 100049,china 2 Graduate university of Chinese Academy of Sciences,beijing 100049,china 3.department of Astronomy,beijing Normal university,beijing 100875,china 4 Computing center,Institute of high Energy Physics,Chinese Academy of Sciences,beijing 100049,china Key laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China department of Astronomy Beijing Normal University Beijing China Computing center Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The hard x.ray modulation telescope hx.T is a low orbit x.ray space telescope whose main science goals are to accomplish a hard x.ray all sky survey and to study timing and spectral characteristics of x.ray *** has three kinds of science instruments:the high energy x.ray detector(hE),the medium energy x.ray detector(ME) and the low energy x.ray detector(LE).The observation schedule of hx.T is a key to achieving the science goal of hx.T,and the analysis of the observation constraints is one of the first tasks in making the observation *** paper analyzes how the observation constraints influence the sky visibility and the visible time distribution of x.ray sources and discusses the schedule strategy with regard to the observation constraints.

关键词： hx.T observation constraints sky visibility