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Spatial and Temporal Dynamics of Surface Water in China from the 1980s to 2015 Based on Remote Sensing Monitoring

Chinese Geographical Science 2022年第1期32卷 174-188页

作者： SONG Song CAO Zheng wu zhifeng CHUAI Xiaowei School of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006China Southern Marine Science and Engineering Guangdong Laboratoty(Guangzhou) Guangzhou 511458China School of Geographic and Oceanographic Science Nanjing UniversityNanjing 210046China

Climate change and human interference play significant roles on dynamic of water body abundance,and drive related hydrological,biochemical and social/economic *** and monitoring surface water area with high resolution multi-temporal satellite imagery provide new perspective to evaluate the dynamics of surface water area,especially in continental and global *** this study,based on the Landsat images from 1980 s to 2015,we surveyed the spatial and temporal variation of surface water area,including rivers,lakes and reservoirs,in 10-yr temporal slice across ***,the driving forces of the variation has been identified to reveal the interaction of water bodies and the changing *** results show that,the water surface area expanded over all three decades with strong spatial and temporal difference,despite the drier and warmer climate background;although lakes comprise the largest portion of the surface water area,the highest contributor of surface water expansion was new constructed reservoir located in the densely populated region;climatic parameters alteration,like precipitation and temperature,resulted in the water surface expansion in the northwestern basin by growing water input linked with rain and glacier melting;in the rest part of China,rise of water surface area was predominately attributed to human relocation of water resource,which yielded more new water storage area than the disappeared water body caused by less precipitation and stronger *** conclusions highlight the integrative water resource management,especially in water conservation and restoration.

关键词： temporal dynamics spatial variation surface water area expansion driving forces

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REDUCING STAIRCASING ARTIFACTS IN SPECT RECONSTRUCTION BY AN INFIMAL CONVOLUTION REGULARIZATION

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Journal of Computational Mathematics 2016年第6期34卷 626-647页

作者： zhifeng wu Si Li Xueying Zeng Andrzej Krol School of Mathematics Guangdong Provincial Key Lab of Computational Science Sun Yat-sen University Guangzhou 510275 P. R. China School of Data and Computer Science Guangdong Provincial Key Lab of Computational Science Sun Yat-sen University Guangzhou 510275 P. R. China School of Mathematical Sciences Ocean University of China Qingdao 266100 P. R. China Department of Radiology and Department of Pharmacology SUNY Upstate Medical University Syracuse NY 13210 USA

The purpose of this paper is to investigate the ability of the infimal convolution regular- ization in curing the staircasing artifacts of the TV model in the SPECT reconstruction. We formulate the problem of SPECT reconstruction with the infimal convolution regu- larization as a convex three-block optimization problem and characterize its solution by a system of fixed-point equations in terms of the proximity operator of the functions involved in its objective function. We then develop a novel fixed-point proximity algorithm based on the fixed-point equations. Moreover, we introduce a preconditioning matrix motivated by the classical MLEM （maximum-likelihood expectation maximization） algorithm. We prove convergence of the proposed algorithm. The numerical results are included to show that the infimal convolution regularization is capable of effectively reducing the staircasing artifacts, while maintaining comparable image and coefficient recovery contrast. quality in terms of the signal-to-noise ratio

关键词： SPECT Infimal Convolution Regularization Staircasing Artifacts Fixed-pointProximity Algorithm.

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Island biogeography theory and the habitat heterogeneity jointly explain global patterns of Rhododendron diversity

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Plant Diversity 2024年第5期46卷 565-574页

作者： Yanwei Guan Yongru wu Zheng Cao zhifeng wu Fangyuan Yu Haibin Yu Tiejun Wang School of Geographical Sciences and Remote Sensing Guangzhou UniversityGuangzhou 510006China School of Life Sciences Guangzhou UniversityGuangzhou 510006China Department of Natural Resources Faculty of Geo-Information and Earth Observation(ITC)University of TwenteDrienerlolaan 5Enschede 7522 NBthe Netherlands

Mountain biodiversity is of great importance to biogeography and ***,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species *** this study,we determined which of six common hypotheses(e.g.,climate hypotheses,habitat heterogeneity hypothesis and island biogeography theory)best explain global patterns of species diversity in *** found that Rhododendron diversity patterns were most strongly explained by proxies of island biogeography theory(i.e.,mountain area)and habitat heterogeneity(i.e.,elevation range).When we examined other relationships important to island biogeography theory,we found that the planimetric area and the volume of mountains were positively correlated with the Rhododendron diversity,whereas the‘mountains-to-mainland’distance was negatively correlated with Rhododendron diversity and shared *** findings demonstrate that Rhododendron diversity can be explained by island biogeography theory and habitat heterogeneity,and mountains can be regarded as islands which supported island biogeography theory.

关键词： Mountain biodiversity Rhododendron Island biogeography theory Habitat heterogeneity Biogeographical hypotheses Plant diversity

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Effect of temperature and moisture on soil organic carbon mineralization of predominantly permafrost peatland in the Great Hing'an Mountains,Northeastern China

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Journal of Environmental Sciences 2010年第7期22卷 1057-1066页

作者： Xianwei Wang Xiuzhen Li Yuanman Hu Jiujun Lv Ju Sun Zongmei Li zhifeng wu Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China

Boreal peatlands represent a large global carbon pool. The relationships between carbon mineralization, soil temperature and moisture in the permafrost peatlands of the Great Hing＇an Mountains, China, were examined. The CO2 emissions were measured during laboratory incubations of samples from four sites under different temperatures （5, 10, 15, and 20℃） and moisture contents （0%, 30%, 60%, 100% water holding capacity （WHC） and completely water saturated）. Total carbon mineralization ranged from 15.51 to 112.92 mg C under the treatments for all sites. Carbon mineralization rates decreased with soil depth, increased with temperature, and reached the highest at 60% WHC at the same temperature. The calculated temperature coefficient （Q10） values ranged from 1.84 to 2.51 with the soil depths and moisture. However, the values were not significantly affected by soil moisture and depth for all sites due to the different peat properties （P 〉 0.05）. We found that the carbon mineralization could be successfully predicted as a two-compartment function with temperature and moisture （R^2 〉 0.96） and total carbon mineralization was significantly affected by temperature and moisture （P 〈 0.05）. Thus, temperature and moisture would play important roles in carbon mineralization of permafrost peatlands in the Great Hing＇an Mountains, indicating that the permafrost peatlands would be sensitive to the environment change, and the permafrost peatlands would be potentially mineralized under future climate change.

关键词： Great Hing'an Mountains permafrost peatland mineralization climate change

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Professor Haowen Xu:The founder of exercise biochemistry in China

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Protein & Cell 2021年第10期12卷 747-750页

作者： Wei Gong Yijing Shen Jiaqi Bao Yike Ying Han Zhou zhifeng wu Zhejiang Normal University Jinhua 321004China East China Normal University Shanghai 200062China

Professor Haowen Xu(许豪文,1935-2004)was a famous sports scientist and the founder of Exercise Biochemistry in China(Fig.1).He dedicated his life to the study of sports science and made tremendous contributions to the formation and growth of the field of Exercise Biochemistry in *** was the first to use theories of exercise biochemistry and sports medicine to guide athletes'training and competition in China(Yu,2006).

关键词： China sports biochemistry

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Symbolic algorithmic verification of intransitive generalized noninterference

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Science China(Information Sciences) 2012年第7期55卷 1650-1665页

作者： ZHOU CongHua,LIU zhifeng,wu HaiLing,CHEN Song & JU ShiGuang School of Computer Science and Telecommunication Engineering,Jiangsu University Zhenjiang 212013,China 1. School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang 212013 China

Generalized noninterference can be used to formulate transitive security policies,but is unsuitable for intransitive security *** propose a new information flow security property,which we call intransitive generalized noninterference,that enables intransitive security policies to be specified ***,we propose an algorithmic verification technique to check intransitive generalized *** technique is based on the search for counterexamples and on the window induction proof,and can be used to verify generalized *** further demonstrate that the search of counterexamples and induction proof can be reduced to quantified Boolean *** reduction enables us to use efficient quantified Boolean decision procedures to perform the check of intransitive generalized *** also reduces spatial requirement by representing the space compactly,and improves the efficiency of the verification procedure.

关键词： intransitive generalized noninterference quantified Boolean satisfiability symbolic verification multi-level security

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Evaluation of the Mechanisms Underlying Amino Acid and Microbiota Interactions in Intestinal Infections Using Germ-Free Animals

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Infectious Microbes & Diseases 2021年第2期3卷 79-86页

作者： Yapeng Yang Peng Bin Shiyu Tao Guoqiang Zhu zhifeng wu Wei Cheng Wenkai Ren Hong Wei State Key Laboratory of Agricultural Microbiology College of Animal Sciences and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina Jiangsu Co-Innovation Center for Important Animal Infectious Diseases and Zoonoses Joint International Research Laboratory of Agriculture and AgriProduct Safety of Ministry of Education of ChinaCollege of Veterinary MedicineYangzhou UniversityYangzhouJiangsuChina State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory of Lingnan Modern AgricultureNational Engineering Research Center for Breeding Swine IndustryGuangdong Provincial Key Laboratory of Animal Nutrition ControlCollege of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina

Intestinal infectious diseases refer to the inflammatory changes in the intestinal tract caused by pathogens(including bacteria,viruses,fungi,protozoa,or parasites)or their toxic products.A large number of microorganisms colonize the intestinal tract of healthy people,which together with the intestinal epithelium constitute the biological barrier of the intestinal tract to resist infectious *** an“invisible organ,”the intestinal flora is closely related to human nutrition metabolism and intestinal infections.A variety of intestinal flora participates in the nutritional metabolism of amino acids,and the small molecular substances produced by the amino acid metabolism through the intestinal flora can enhance intestinal immunity and resist bacterial *** turn,amino acids can also regulate the composition of the intestinal flora,maintain the steady-state of the intestinal flora,protect the intestinal barrier,and inhibit colonization by pathogenic *** a model animal with a clear microbial background,germ-free(GF)animals can clarify the mechanisms of interactions between intestinal microbes and amino acid metabolism in intestinal infections by combining genetic engineering technology and multi-omics *** article reviews related researches on the involvement of intestinal microbes in host amino acid metabolism and resistance to intestinal infections and discusses the advantages of GF animal models for studying the underlying *** GF animal model is helpful to further study the intervention effects of amino acid metabolism of targeted intestinal flora on intestinal infections.

关键词： germ-free animal intestinal barrier intestinal flora intestinal immunity intestinal infection metabolism of amino acids

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Urban vacant land in growing urbanization:An international review

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Journal of Geographical Sciences 2020年第4期30卷 669-687页

作者： SONG Xiaoqing WEN Mengmeng SHEN Yajing FENG Qi XIANG Jingwei ZHANG Weina ZHAO Guosong wu zhifeng Research Center for Spatial Planning and Human-Environment System Simulation School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China Hunan Key Laboratory of Land Resources Evaluation and Utilization Hunan Planning Institute of Land and ResourcesChangsha 410007China School of Public Administration China University of GeosciencesWuhan 430074China School of Geographical Sciences Guangzhou UniversityGuangzhou 510006China

Urban growth and shrinkage constitute the overall pattern of growing urbanization across the *** on urban vacant land(UVL)are few,and have proved to be mainly rudimentary and *** paper first presents the definition of UVL based on bibliometric ***,morphology,proximate causes,and the multiple functions of UVL are then analyzed at parcel,transect,city,and national levels based on an international *** show that UVL can be categorized by land cover,land usage,and land ***,UVL has been widespread and *** example,the occurrence probabilities of UVL in the cases of Guangzhou and New York are 8.46%-8.88%and 3.17%-5.08%,*** average vacancy rate of residential land amounts to 11.48%in 65 ***,UVL shows fragmentation and irregular shape,and significant spatial differences exist at parcel,transect,city,and national *** causes,such as excessive land division,irregularly shaped land parcels,decreases in resident population,deindustrialization,land speculation,insufficient investment,and environmental concerns,can all result in ***,UVL has become a gray area of social,economic,and ecological ***,it can also be considered a potential resource for enhancing urban *** implications to promote urban sustainability using monitoring,control,and differential revitalization of UVL are presented.

关键词： urban vacant land urbanization shrinking cities land use transition

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Evaluation the uncertainty of the fiber spectroradiometer

Evaluation the uncertainty of the fiber spectroradiometer

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国防光电子论坛第二届新型探测技术及其应用研讨会

作者： wu zhifeng Dai Caihong Wang Yanfei Optcial division National Institute of Metrology

The fiber spectroradiometer is now widely used in the photometry and radiometry due to the convenience. Before use the calibration is usually traced back to the tungsten lamp with known spectral irradiance. However, the working condition may differ greatly from the calibration condition, such as the signal level, the spectrum shape, and et al. In the experiment,characteristics of the fiber spectroraidometer are investigated, such as the short time stability, the nonlinear phenomena due to the integration time and signal level. Uncertainty of the calibration is evaluated taking all the factors into account.

关键词： fiber spectroradiometer radiometry nonlinear uncertainty

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论股份制银行的组织结构

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金融论坛 2005年第6期10卷 33-38,63页

作者：吴志峰北京大学光华管理学院-招商银行博士后科研工作站深圳518040

在国有商业银行改革加速和外资银行全面竞争日近两大背景下,股份制银行面临制度创新和业务创新的双重压力,其组织结构调整迫在眉睫。本文在考察组织结构理论与实践发展的基础上,针对现行组织结构的五大弊端,构建了能消除弊端、适应股份... 详细信息

在国有商业银行改革加速和外资银行全面竞争日近两大背景下,股份制银行面临制度创新和业务创新的双重压力,其组织结构调整迫在眉睫。本文在考察组织结构理论与实践发展的基础上,针对现行组织结构的五大弊端,构建了能消除弊端、适应股份制银行实践发展的新的组织结构形式:即业务事业部与地区事业部相结合的矩阵结构。在此基础上分析了审贷与风险控制部门子结构的框架,提出分行审贷与风险控制部门直属总行,建立行业专家与地区专家相结合的风险控制结构。

关键词：股份制银行国有商业银行改革组织结构调整组织结构理论组织结构形式实践发展风险控制外资银行业务创新制度创新矩阵结构控制结构行业专家事业部审贷总行部门分行

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