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Combining in-situ water quality and remotely sensed data across spatial and temporal scales to measure variability in wet season chlorophyll-a:Great Barrier Reef lagoon(Queensland,Australia)

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Ecological Processes 2013年第1期2卷 328-349页

作者： Michelle J Devlin Eduardo Teixeira da Silva Caroline Petus Amelia Wenger Daniel Zeh Dieter Tracey Jorge GÁlvarez-Romero Jon Brodie Catchment to Reef research Group TropWaterJames Cook UniversityTownsvilleQLD4811Australia australian research Council centre of Excellence for Coral Reef Studies James Cook UniversityTownsvilleQLDAustralia School of Marine and Tropical Biology James Cook UniversityTownsvilleQLDAustralia

Introduction:Combining in-situ data from single-point time series with remotely sensed spatial data allowed a greater elucidation of changes in chlorophyll-a concentrations through wet season conditions in the Great Barrier Reef coastal ***:Single-point time-series data were collected from 2006 to 2012 during high river flow conditions to assess changes in phytoplankton biomass(measured as chlorophyll-a).Additionally,three flood plume water types,derived from classified true-colour Aqua moderate resolution imaging spectroradiometer(MODIS)images,were used to group single-point time-series data for the phytoplankton biomass ***:Survey data illustrate the heterogeneity of chlorophyll-a distribution over seasonal and inter-annual cycles and the difficulty in describing community responses through the wet *** spatial data demonstrate distinct regional differences throughout the Great Barrier *** high chlorophyll-a concentrations measured in flood plume waters immediately adjacent to the inshore,highly turbid‘inner’flood plume are a product of sufficient light,given most of the suspended solids have settled from the plume,and the availability of sufficient nutrients,which drive higher phytoplankton production and characterise the formation of secondary stage flood *** formation and extent of these secondary flood plumes were mapped using MODIS true-colour satellite *** distance and the location of the secondary plume water are reliant on flow,coastal hydrodynamics,and biological ***:The combination of in-situ data and remotely sensed data provides information on the complexity of these coastal processes during the wet season and offers managers a more comprehensive understanding of the extent of nutrient enrichment in the Great Barrier Reef coastal area and the potential influence of flood plumes on coastal marine ecosystems.

关键词： Chlorophyll-a Great barrier reef Phytoplankton Monitoring Remote sensing MODIS

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Comprehensive and high-resolution emission inventory of atmospheric pollutants for the northernmost cities agglomeration of Harbin-Changchun,China:Implications for local atmospheric environment management

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Journal of Environmental Sciences 2021年第6期33卷 150-168页

作者： Mengduo Zhang Weiwei Chen Xiangjin Shen Hongmei Zhao Chengkang Gao Xuelei Zhang Wei Liu Chengjiang Yang Yang Qin Shichun Zhang Jing Fu Daniel Tong Aijun Xiu Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Northeastern University School of Metallurgy Shenyang 110819China Heilongjiang Provincial Academy of Environmental Sciences Harbin 150090China Jilin Provincial Ecological Environment Monitoring Center Changchun 130012China Center for spatial information Science and Systems George Mason UniversityFairfaxVA 22030USA cooperative Institute for Climate&Satellites University of MarylandCollege ParkMD 20740USA

Using a bottom-up estimation method,a comprehensive,high-resolution emission inventory of gaseous and particulate atmospheric pollutants for multiple anthropogenic sectors with typical local sources has been developed for the Harbin-Changchun city agglomeration(HCA).The annual emissions for CO,NO_(x),SO_(2),NH_(3),VOC S,PM_(2.5),PM 10,BC and OC during 2017 in the HCA were estimated to be 5.82 Tg,0.70 Tg,0.34 Tg,0.75 Tg,0.81 Tg,0.67 Tg,1.59 Tg,0.12 Tg and 0.26 Tg,*** PM 10 and SO_(2),the emissions from industry processes were the dominant contributors representing 54.7%and 49.5%,respectively,of the total emissions,while 95.3%and 44.5%of the total NH_(3)and NO x emissions,respectively,were from or associated with agricultural activities and *** distributions showed that most emissions(except NH_(3))occurred in November to March and were concentrated in the central cities of Changchun and Harbin and the surrounding *** burning of straw made an important contribution to PM_(2.5)in the central regions of the northeastern plain during autumn and spring,while domestic coal combustion for heating purposes was significant with respect to SO_(2)and PM_(2.5)emissions during autumn and ***,based on Principal Component Analysis and Multivariable Linear Regression model,air temperature,relative humidity,electricity and energy consumption,and the urban and rural population were optimized to be representative indicators for rapidly assessing the magnitude of regional atmospheric pollutants in the *** indicators and equations were demonstrated to be useful for local atmospheric environment management.

关键词： Anthropogenic emissions Inventory Air quality Atmospheric pollution Environmental management Northern China

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spatially resolved transcriptomics in immersive environments

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Visual Computing for Industry,Biomedicine,and Art 2022年第1期5卷 12-24页

作者： Denis Bienroth Hieu TNim Dimitar Garkov Karsten Klein Sabrina Jaeger-Honz Mirana Ramialison Falk Schreiber Department of Computer and information Science University of KonstanzKonstanzGermany Cell Biology Murdoch Children’s Research InstituteParkvilleMelbourneVICAustralia australian Regenerative Medicine Institute Monash UniversityClaytonMelbourneVICAustralia Systems Biology Institute Australia ClaytonMelbourneVICAustralia Faculty of information Technologies Monash UniversityMelbourneAustralia

spatially resolved transcriptomics is an emerging class of high-throughput technologies that enable biologists to systematically investigate the expression of genes along with spatial *** data acquisition,one major hurdle is the subsequent interpretation and visualization of the datasets *** address this challenge,VR-Cardiomics is presented,which is a novel data visualization system with interactive functionalities designed to help biologists interpret spatially resolved transcriptomic *** implementing the system in two separate immersive environments,fish tank virtual reality(FTVR)and head-mounted display virtual reality(HMD-VR),biologists can interact with the data in novel ways not previously possible,such as visually exploring the gene expression patterns of an organ,and comparing genes based on their 3D expression ***,a biologist-driven use-case is presented,in which immersive environments facilitate biologists to explore and compare the heart expression profiles of different genes.

关键词： spatially-resolved transcriptomics spatial transcriptomics Virtual reality Fish tank virtual reality Head-mounted display Immersive analytics Immersive environment

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Performance of cooperative spatial Modulation with AF Protocol in Wireless Relay Network

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Chinese Journal of Electronics 2019年第1期28卷 143-151页

作者： YU Xiangbin PAN Qing WANG Cheng College of Electronic and information Engineering Nanjing University of Aeronautics and Astronautics National Mobile Communications research Laboratory Southeast University

By combing spatial modulation(SM) with the Amplify-and-forward(AF) cooperative communication, a cooperative SM scheme with AF(AF-SM) protocol is presented, and the corresponding Bit error rate(BER)performance is investigated. Based on the performance analysis, the error probability of antenna index estimation(Pa) and the error probability of symbol estimation(Pd),which constitutes the overall average BER, are derived,respectively. As a result, tightly approximate closedform expressions of Paand Pdare attained, *** these expressions, the closed-form overall average BER is achieved. During the analysis, the computational complexity of AF-SM detector is also provided in terms of the complex addition and multiplication ***, the asymptotic BER at high SNR and the corresponding diversity gain are further derived, and the resultant diversity gain of Nr+ 1 is obtained for the system with Nrreceive antennas. Simulation results show that our theoretical analysis is valid, and provides good performance evaluation method for cooperative SM system. Moreover, the BER performance can be effectively improved as Nrincreases due to higher diversity gain.

关键词： spatial modulation(SM) cooperative communication Amplify and forward protocol Diversity gain Average bit error rate

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Added-value of GEO-hyperspectral Infrared Radiances for Local Severe Storm Forecasts Using the Hybrid OSSE Method

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Advances in Atmospheric Sciences 2021年第8期38卷 1315-1333页

作者： Pei WANG Zhenglong LI Jun LI Timothy JSCHMIT cooperative Institute for Meteorological Satellite Studies University of Wisconsin-MadisonMadisonWI53706USA Advanced Satellite Product Branch Center for Satellite Applications and ResearchNESDIS/NOAAMadisonWI53706USA

High spectral resolution(or hyperspectral)infrared(IR)sounders onboard low earth orbiting satellites provide high vertical resolution atmospheric information for numerical weather prediction(NWP)*** contrast,imagers on geostationary(GEO)satellites provide high temporal and spatial resolution which are important for monitoring the moisture associated with severe weather systems,such as rapidly developing local severe storms(LSS).A hyperspectral IR sounder onboard a geostationary satellite would provide four-dimensional atmospheric temperature,moisture,and wind profiles that have both high vertical resolution and high temporal/spatial *** this work,the added-value from a GEO-hyperspectral IR sounder is studied and discussed using a hybrid Observing System Simulation Experiment(OSSE)method.A hybrid OSSE is distinctively different from the traditional OSSE in that,(a)only future sensors are simulated from the nature run and(b)the forecasts can be evaluated using real *** avoids simulating the complicated observation characteristics of the current systems(but not the new proposed system)and allows the impact to be assessed against real *** Cross-track Infrared Sounder(CrIS)full spectral resolution(FSR)is assumed to be onboard a GEO for the impact studies,and the GEO CrIS radiances are simulated from the ECMWF Reanalysis v5(ERA5)with the hyperspectral IR all-sky radiative transfer model(HIRTM).The simulated GEO CrIS radiances are validated and the hybrid OSSE system is verified before the impact *** LSS cases from 2018 and 2019 are selected to evaluate the value-added impacts from the GEO CrIS-FSR *** impact studies show improved atmospheric temperature,moisture,and precipitation forecasts,along with some improvements in the wind *** added-value,consisting of an overall 5%Root Mean Square Error(RMSE)reduction,was found when a GEO CrIS-FSR is used in replacement of LEO ones indicat-ing the potential for a

关键词： GEO hyperspectral IR hybrid OSSE satellite data assimilation

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The impact of time synchronization error on passive coherent pulsed radar system

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Science China(information Sciences) 2010年第12期53卷 2664-2674页

作者： HE You 1,ZHANG CaiSheng 1,2,DING JiaHui 2 & TANG XiaoMing 1 1 research Institute of information Fusion,Naval Aeronautical and Astronautical University,Yantai 264001,China 2 Nanjing research Institute of Electronics Technology,Nanjing 210039,China research Institute of information Fusion Naval Aeronautical and Astronautical University Yantai China Nanjing research Institute of Electronics Technology Nanjing China

Passive bistatic coherent radar system operates with distinct non-cooperative transmitter and receiver located at different *** such spatial separation,the receiving system needs to independently solve the problem of time and phase synchronization via direct-path *** impact of time synchronization error was explored and solved in passive bistatic coherent *** common model of digital sampling process is introduced to illustrate the effect of time synchronization error(TSE).The periodicity of relative sample instant variation of each pulse is ***,normalized interference power(NIP) is defined to evaluate the potential impact of *** NIP expressions are derived when the difference between the adjacent relative sample instant is uniform distribution or Gaussian *** is found that there are new spurious frequency components and the detection performance is decreased in the case of asynchronous *** the same time,the analytical Doppler frequency bias expression caused by TSE is *** results are confirmed by simulation in the cases of different periods of relative sampling instant.

关键词： passive coherent radar(PCR) time synchronization error(TSE) normalized interference power(NIP)

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Spatiotemporal Pattern of Cultivated Land Pressure and Its Influencing Factors in the Huaihai Economic Zone, China

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Chinese Geographical Science 2023年第2期33卷 287-303页

作者： LI Yi FANG Bin LI Yurui FENG Weilun YIN Xu School of Geography Nanjing Normal UniversityNanjing 210023China research Center of New Urbanization and Land Problem Nanjing Normal UniversityNanjing 210023China Jiangsu Provincial Geographic information Resources Development and Utilization cooperative Innovation Center Nanjing 210023China Institute of Geographic Sciences and Natural Resources research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101China School of Geographic Science Hebei Normal UniversityShijiazhuang 050024China

Cultivated land pressure represents a direct reflection of grain security. Existing relevant studies rarely approached the spatiotemporal pattern of cultivated land pressure or the spatial heterogeneity of its influencing factors from the level of economic *** the Huaihai Economic Zone(HEZ), China for case analysis, this study investigated the spatiotemporal pattern of cultivated land pressure in diverse periods from 2000 to 2018 based on a modified cultivated land pressure index and spatial correlation models. On this basis, it explored the influencing factors of the spatial differentiation of cultivated land pressure in the late stage of the study using geographical detector as well as multi-scale geographically weighted regression model. The results indicated that: 1) in the study period, the global cultivated land pressure index of the study area decreased gradually, but cultivated land pressure increased locally in a significant way, especially in the central and southern Shandong Province;2) the spatial pattern of cultivated land pressure manifested global clustering features. Hot and secondary-hot spots presented a narrowing and clustering trend, whereas cold and secondary-cold spots manifested a spreading and clustering trend;3) average slope, the proportion of non-grain crops, population urbanization rate, and multiple cropping index have significant effects on the spatial differentiation of cultivated land pressure. The former three factors were positively correlated with cultivated land pressure, and the last factor was negatively correlated with cultivated land pressure;and 4) the amount of cultivated land has increased in the central and southern Shandong Province through land consolidation which, nonetheless, failed to improve the grain production. In regards to major grain producing areas similar to the HEZ in China, the authors suggest that great importance should be given to the balance of the quality and quantity of cultivated land, the op

关键词： cultivated land pressure spatiotemporal pattern influencing factors Huaihai Economic Zone China

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Street Mapping of Ife Metropolis, Osun State, Nigeria

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Journal of Geographic information System 2016年第3期8卷 387-395页

作者： Idowu Sunday Kolawole Taofik Abayomi Alaga Samson Akintunde Ogunyemi Oladimeji Samuel Popoola Mustapha Olayemi Oloko-Oba Advanced Space Technology Application Laboratory (ASTAL) Cooperative Information Network (COPINE) National Space Research and Development Agency (NASRDA) Obafemi Awolowo University Campus Ile Ife Nigeria

The importance of Remote Sensing and Geographic information System in map making cannot be overemphasized because of its ability to integrate spatial data with non-spatial data and also communicate the resulting information in a way that everyone would understand. Several works have taken advantage of the abilities of these technologies to produce street maps using High Resolution Images. The increase in development in Ile Ife, Osun State, Nigeria, has brought about navigation challenge and associated difficulties. This work intends to produce a street map that will ease navigation within the study area and help in road network analysis, site suitability analysis etc. Aerial Photographs, captured in the year 2009 and GeoEye1 Satellite Image of 2011 were used to extract the road network of Ife Metropolis. The image was imported into ArcGIS environment, where the database was created having feature datasets such as roads and special features. To have all the elements in vector format, the image was digitized. The street names collected from the field work was inputted into the database and then subjected to cartographical processes. 512 Roads were captured within four classes of Road Network namely Express road (5), Secondary Road (25), Primary Roads (22) and Street Road (460). This field work revealed that a larger percentage of the roads were not paved, while most of the paved ones have deteriorated and the newly constructed ones were not documented. It also showed that some of the roads were not named according to the standard and some were not named at all. From this study, we recommend that the naming system should be standardized across the study area. It is also recommended that provision should be made for street map revision on a yearly basis so as to account for changes.

关键词： Remote Sensing Geographic information System Aerial Photograph Digitization

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High-power,electronically controlled source of user-defined vortex and vector light beams based on a few-mode fiber amplifier

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Photonics research 2021年第5期9卷 856-864页

作者： DI LIN JOEL CARPENTER YUTONG FENG YONGMIN JUNG SHAIF-UL ALAM DAVID J.RICHARDSON Optoelectronics research centre University of SouthamptonSouthampton SO171BJUK School of information Technology and Electrical Engineering The University of QueenslandBrisbaneQLD 4072Australia

Optical angular momentum(OAM)-based structured light beams provide an additional degree of freedom for practical applications ranging from optical communication to laser-based material processing. Many techniques exist for generating such beams within laser sources and these primarily rely upon the use of specially designed optical components that limit laser power scaling and ready tunability of the topological charge and polarization of the output OAM beams. Here we show that some of these limitations can be overcome by employing a computer controlled reflective phase-only spatial light modulator to adaptively tailor the input(and subsequent output) beam wavefront and polarization in a few-mode fiber amplifier. In this way modal-coupling-induced beam distortion within the fiber amplifier can be mitigated and we are able to generate at will any desired supported spatial mode guided in the fiber, including conventional linearly polarized(LP) modes, scalar OAM modes, and cylindrical vector modes, at average powers >10 W and with a peak power of >11 kW. Our results pave the way to the realization of practical high-power structured laser sources with tunable chirality and polarization.

关键词： amplifier fiber power

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一种能实现单频PPP-RTK的GNSS局域参考网数据处理算法

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地球物理学报 2015年第7期58卷 2306-2319页

作者：张宝成 ODIJK Dennis 中国科学院测量与地球物理研究所动力大地测量学国家重点实验室武汉430077 GNSS research centre Department of Spatial SciencesCurtin University

全球范围内大量布设的GNSS（Global Navigation Satellite System）参考网为精密定位、导航和授时等应用提供了丰富的数据资源.基于局域参考网,先后发展了若干侧重实现双频精密定位的技术,如NRTK（Network Real Time Kinematic）,PPP（P... 详细信息

全球范围内大量布设的GNSS（Global Navigation Satellite System）参考网为精密定位、导航和授时等应用提供了丰富的数据资源.基于局域参考网,先后发展了若干侧重实现双频精密定位的技术,如NRTK（Network Real Time Kinematic）,PPP（Precise Point Positioning）和PPP-RTK等.其中,PPP-RTK融合了NRTK和PPP的技术优势,是目前相关研究的热点.本文改进了利用局域参考网提取各类改正信息的算法,以便于实现单频PPP-RTK,具体步骤包括：1）逐参考站实施非组合PPP,并固定已知站星距和卫星钟差,预估电离层延迟、浮点模糊度等参数;2）联合所有参考站的PPP模糊度预估值,通过重新参数化,形成一组双差整周模糊度和接收机、卫星相位偏差;3）固定双差整周模糊度,精化求解卫星相位偏差和各参考站PPP电离层延迟.基于网解中用到的卫星轨道和钟差,以及网解所提供的卫星相位偏差和（内插的）电离层延迟,参考网内的单频流动站即可实施PPP-RTK.基于澳大利亚某连续运行参考站网和流动站的实测数据,考察了：1）参考网数据处理中,双差模糊度的固定成功率（98.89%）和卫星相位偏差估值的时间稳定性（各连续弧段优于0.2周）;2）流动站处电离层延迟的内插精度（优于10cm）;3）单天内任一历元起算,固定静态（动态）单频PPP整周模糊度所需时长（均不超过10min）;4）模糊度固定前后,单频动态PPP的定位精度（模糊度固定后,平面和天顶RMS分别优于5cm和10cm;模糊度固定前,相应RMS仅为28～53cm）.

关键词：单频PPP-RTK 卫星相位偏差电离层延迟整周模糊度固定

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