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Application of GPS technology to build a mine-subsidence observation station 被引量:16
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作者 LU Wei-cai CHENG Shi-guang +1 位作者 YANG Hai-sheng LIU Da-peng 《Journal of China University of Mining and Technology》 EI 2008年第3期377-380,共4页
We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers ... We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers various geologic and mining con-ditions. Having analyzed the aims of the joint survey and the comprehensive survey, we propose design principles, and work modes, for adopting GPS technology as the position measuring technique to be used in these two stages. Baseline vectors and spatial ad-justments of the GPS network were calculated after study of data processing and quality estimation methods. A coordinate system transformation and error estimates of the transformed GPS network data are discussed. The error estimates in all stages show that the GPS control network of the observation station has sufficient accuracy and is highly efficient. The network thus provides a reli-able datum for analyzing the laws of surface displacement and deformation induced by mining. 展开更多
关键词 GPS subsidence observation station initial observation data processing flow quality evaluating
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Concept Design,Modeling and Station-keeping Attitude Control of an Earth Observation Platform 被引量:2
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作者 YANG Yuenen WU Jie ZHENG Wei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1245-1254,共10页
The stratosphere airship provides a unique and promising platform for earth observation. Researches on the project design and control scheme for earth observation platforms are still rarely documented. Nonlinear dynam... The stratosphere airship provides a unique and promising platform for earth observation. Researches on the project design and control scheme for earth observation platforms are still rarely documented. Nonlinear dynamics, model uncertainties, and external disturbances contribute to the difficulty in maneuvering the stratosphere airship. A key technical challenge for the earth observation platform is station keeping, or the ability to remain fixed over a geo-location. This paper investigates the conceptual design, modeling and station-keeping attitude control of the near-space earth observation platform. A conceptual design of the earth observation platform is presented. The dynamics model of the platform is derived from the Newton-Euler formulation, and the station-keeping control system of the platform is formulated. The station-keeping attitude control approach for the platform is proposed. The multi-input multi-output nonlinear control system is decoupled into three single-input single-output linear subsystems via feedback linearization, the attitude controller design is carried out on the new linear systems using terminal sliding mode control, and the global stability of the closed-loop system is proven by using the Lyapunov theorem. The performance of the designed control system is simulated by using the variable step Runge-Kutta integrator. Simulation results show that the control system tracks the commanded attitude with an error of zero, which verify the effectiveness and robustness of the designed control system in the presence of parametric uncertainties. The near-space earth observation platform has several advantages over satellites, such as high resolution, fast to deploy, and convenient to retrieve, and the proposed control scheme provides an effective approach for station-keeping attitude control of the earth observation platform. 展开更多
关键词 earth observation platform novel design attitude control terminal sliding mode station keeping near-space
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Maintenance of Storage Batteries in Automatic Meteorological Observation Stations 被引量:1
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作者 Yanjun Du Bin Zhang Chaochang Zhang 《Meteorological and Environmental Research》 CAS 2013年第5期52-53,共2页
Firstly, the definition, structure and working principles of storage batteries in automatic meteorological observation stations were stated simply, and then the daily maintenance of the storage batteries were introduc... Firstly, the definition, structure and working principles of storage batteries in automatic meteorological observation stations were stated simply, and then the daily maintenance of the storage batteries were introduced according to previous practical experience, finally typical faults of storage batteries were analyzed. Practical evidence shows that timely external maintenance and enough supply of electrolyte can greatly extend the lifespan of storage batteries. 展开更多
关键词 Automatic meteorological observation station Storage battery Maintenance China
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Comprehensive Assessment and Analysis of National Surface Meteorological Observation Stations: A Case Study of Hebei Province
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作者 Liu Huanli Fan Zenglu Li Chan 《Meteorological and Environmental Research》 CAS 2019年第4期45-50,60,共7页
With the rapid development of China s economic construction and the rapid advancement of urban-rural integration construction, meteorological detection environment has been damaged repeatedly, which seriously affects ... With the rapid development of China s economic construction and the rapid advancement of urban-rural integration construction, meteorological detection environment has been damaged repeatedly, which seriously affects the representativeness, accuracy, and comparability of meteorological data, so it is urgent to protect meteorological detection environment. Based on the investigation and evaluation method of detection environment of national ground meteorological observation stations and high-altitude meteorological observation stations, satellite remote sensing data, and climate analysis method, the evaluation method of detection environment and meteorological data was improved to comprehensively assess the detection environment and meteorological data of stations. After the evaluation results were compared with the results of the survey and evaluation in 2013, it is found that the new assessment method maintains the continuity of detection environment assessment and can objectively reflect the changes of the station detection environment. The research on the method and standard for the evaluation of detection environment and data analysis of meteorological stations provides a scientific basis for the establishment of detection environmental protection plans by stations at all levels, and provides technical support for the scientific and rational adjustment of station network by administrative departments at all levels. 展开更多
关键词 Surface METEOROLOGICAL observation station Detection environment Evaluation method
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Intercomparison of the South Asian High in NCEP1, NCEP2, and ERA-40 Reanalyses and in Station Observations 被引量:1
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作者 FU Jian-Jian LI Shuanglin 《Atmospheric and Oceanic Science Letters》 2012年第3期189-194,共6页
The South Asian Highs (SAHs) at 100 hPa over China in the three reanalysis datasets NCEP1, NCEP2, and ERA-40 are evaluated by using station observation data. The results demonstrate a substantial discrepancy even betw... The South Asian Highs (SAHs) at 100 hPa over China in the three reanalysis datasets NCEP1, NCEP2, and ERA-40 are evaluated by using station observation data. The results demonstrate a substantial discrepancy even between the reanalyses. First, the data of the three reanalyses generally underestimate the intensity of the SAH in the China domain. Second, there are interdecadal changes in the SAH, with highs in the 1960s and 1980s and lows in the 1970s, 1990s, and 2000s. This interdecadal variation of the SAH can be well depicted with NCEP1 data, but the high in the 1980s is missed by ERA-40. The NCEP2 corresponds well with NCEP 1 and captures the decreasing trend after 1979. Furthermore, the NCEP1 reanalysis overestimates the interdecadal changes of SAH, while ERA-40 underestimates the interdecadal changes. This work suggests that much caution should be exerted when the reanalysis datasets are adopted to study the interdecadal variability of SAH. 展开更多
关键词 South Asian High interdecadal change reanalysis datasets station observation
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Comparative Analysis on Observation Data of the Transfer Station in Nanning National Weather Station
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作者 CHENG Ai-zhen XU Jia-ling +1 位作者 HUANG Lin WANG Chao-qiu 《Meteorological and Environmental Research》 CAS 2012年第12期85-88,共4页
[Objective] The research aimed to analyze difference of the observation data by transfer station in Nanning National Weather Station. [Method] By using observation data (atmospheric pressure, temperature, relative hum... [Objective] The research aimed to analyze difference of the observation data by transfer station in Nanning National Weather Station. [Method] By using observation data (atmospheric pressure, temperature, relative humidity, wind direction and speed, precipitation, sunshine, etc.) from January to December in 2000 at old and new Nanning National Weather Station, difference of the each meteorological factor was contrasted. Main reason for difference of the each meteorological factor was analyzed from altitude, underlying surface property and station environment. [Result] Atmospheric pressure and temperature at new station were both lower than that at old station, while relative humidity and wind speed were both higher than that at old station. Rainfall and sunshine had big differences at new and old stations, but variation did not have rule. Main reasons for obvious difference of the meteorological factor were that altitude, observation environment, terrain and underlying surface property at new and old stations were different. Influences of the altitude and observation environment were especially significant. [Conclusion] The research provided basis for continuity and homogeneity correction of the data sequence at Nanning National Weather Station. 展开更多
关键词 Transfer station Comparative observation DIFFERENCE Cause analysis Nanning of Guangxi China
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The Source and Observation System of Binchuan Earthquake Signal Transmitting Seismic Station and Its Preliminary Observation Results
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作者 Wang Bin Li Xiaobin +4 位作者 Liu Zifeng Yang Jun Yang Runhai Wang Baoshan Yang Wei 《Earthquake Research in China》 CSCD 2016年第3期316-325,共10页
This paper summarizes the basic situation of the Binchuan Transmitting Seismic Station and the geophysical observations of the area where it is located,with a focus on the constitution of the observation system of the... This paper summarizes the basic situation of the Binchuan Transmitting Seismic Station and the geophysical observations of the area where it is located,with a focus on the constitution of the observation system of the transmitting seismic station,the excitation characteristics and propagation distance of signals excited by the airgun source in the reservoir and well. The paper also summarizes and discusses on the results of the observations and problems encountered since the Transmitting Seismic Station was built.Finally,this paper proposes the main research to be carried out on the basis of the project aims. 展开更多
关键词 Transmitting Seismic station Active source observation system
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Comparison and Analysis of Data at Traffic Meteorological Observation Station during Beijing Winter Olympic Games Period
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作者 Chunai WU Shuofei WANG Ting MA 《Meteorological and Environmental Research》 CAS 2022年第3期56-57,共2页
This paper presents a comparison and analysis method of data at traffic meteorological observation station during Beijing Winter Olympic Games period based on Grubbs criterion. By comparing the data of a set of standa... This paper presents a comparison and analysis method of data at traffic meteorological observation station during Beijing Winter Olympic Games period based on Grubbs criterion. By comparing the data of a set of standard multi-element observation stations with the data of multiple measured traffic stations, the outliers of each element data at each station were analyzed. It could provide data support for the maintenance of Zhangjiakou traffic meteorological observation station and a guarantee for the accuracy of forest service during Beijing Winter Olympic Games period. 展开更多
关键词 Grubbs criterion Beijing Winter Olympic Games Traffic meteorological observation station OUTLIERS
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Experimental Studies of Icing Resistanceand Observation of Icing Sleet in Heavy Icing Areaat Huangmaogeng Icing Observation Station
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作者 LiuYu XiongHaixing ChangZhineng 《Electricity》 1999年第4期35-37,共3页
关键词 Experimental Studies of Icing Resistanceand observation of Icing Sleet in Heavy Icing Areaat Huangmaogeng Icing observation station
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Technical development of operational in-situ marine monitoring and research on its key generic technologies in China 被引量:1
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作者 Yunzhou Li Juncheng Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第10期117-126,共10页
In China,operational in-situ marine monitoring is the primary means of directly obtaining hydrological,meteorological,and oceanographic environmental parameters across sea areas,and it is essential for applications su... In China,operational in-situ marine monitoring is the primary means of directly obtaining hydrological,meteorological,and oceanographic environmental parameters across sea areas,and it is essential for applications such as forecast of marine environment,prevention and mitigation of disaster,exploitation of marine resources,marine environmental protection,and management of transportation safety.In this paper,we summarise the composition,development courses,and present operational status of three systems of operational in-situ marine monitoring,namely coastal marine automated network station,ocean data buoy and voluntary observing ship measuring and reporting system.Additionally,we discuss the technical development in these in-situ systems and achievements in the key generic technologies along with future development trends. 展开更多
关键词 marine observation technology operational in-situ marine monitoring C-MAN station ocean data buoy VOS measuring and reporting system achievements in the key technologies development trend
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Parametric formation control of multiple nanosatellites for cooperative observation of China Space Station
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作者 Hao Zhou Bohan Jiao +1 位作者 Zhaohui Dang Jianping Yuan 《Astrodynamics》 EI CSCD 2024年第1期77-95,共19页
This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple nanosatellites.First,a simplified geometrical model of the CSS is constructed usi... This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple nanosatellites.First,a simplified geometrical model of the CSS is constructed using fundamental solids,such as the capsule body and cuboid.Second,the spacecraft formation configuration for the observation mission is characterized by a three-dimensional(3D)Lissajous curve using related design parameters under the full-coverage observation requirements of specific parts,such as the CSS connecting section and collision avoidance constraints.Third,a double-layer control law is designed for each nanosatellite,in which the upper layer is a distributed observer for recognizing the target formation configuration parameters,and the lower layer is a trajectory-tracking controller to make the nanosatellite converge to its temporary target position calculated from the upper layer’s outputs.The closed-loop control stability is proven under the condition that the communication network topology of the nanosatellite cluster contains a directed spanning tree.Finally,the control method is verified by numerical simulation,where the CSS connecting section is selected as the observation target,and ten small nanosatellites are assumed to perform the cooperative observation mission.The simulation results demonstrate that the double-layer control law is robust to single-point communication failures and suitable for the accompanying missions of large space objects with multiple nanosatellites. 展开更多
关键词 China Space station(CSS) cooperative observation parametric formation 3D Lissajous curve double-layer system
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Effects of Wind Fences on the Wind Environment around Jang Bogo Antarctic Research Station
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作者 Jang-Woon WANG Jae-Jin KIM +5 位作者 Wonsik CHOI Da-Som MUN Jung-Eun KANG Hataek KWON Jin-Soo KIM Kyung-Soo HAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第12期1404-1414,共11页
This study investigated the flow characteristics altered by Jang Bogo Antarctic Research Station using computational fluid dynamics(CFD) modeling. The topography and buildings around Jang Bogo Station were constructed... This study investigated the flow characteristics altered by Jang Bogo Antarctic Research Station using computational fluid dynamics(CFD) modeling. The topography and buildings around Jang Bogo Station were constructed with computeraided-design data in the CFD model domain. We simulated 16 cases with different inflow directions, and compared the flow characteristics with and without Jang Bogo Station for each inflow direction. The wind data recorded by the site’s automatic weather station(AWS) were used for comparison. Wind rose analysis showed that the wind speed and direction after the construction of Jang Bogo Station were quite different from those before construction. We also investigated how virtual wind fences would modify the flow patterns, changing the distance of the fence from the station as well as the porosity of the fence. For westerly inflows, when the AWS was downwind of Jang Bogo Station, the decrease in wind speed was maximized(-81% for west-northwesterly). The wind speed reduction was also greater as the distance of the fence was closer to Jang Bogo Station. With the same distance, the fence with medium porosity(25%–33%) maximized the wind speed reduction.These results suggest that the location and material of the wind fence should be selected carefully, or AWS data should be interpreted cautiously, for particular prevailing wind directions. 展开更多
关键词 Jang Bogo Antarctic Research station CFD model observation environment wind fence porosity
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Study on tidal gravity observations obtained at stations Zhongshan and Changcheng, Antarctic 被引量:2
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作者 徐建桥 郝兴华 +1 位作者 孙和平 吕纯操 《地震学报》 CSCD 北大核心 2001年第3期307-313,共7页
Based on the international tidal gravity reference values at station Wuhan, the tidal gravity parameters, including the amplitude factors and phase differences are determined accurately by using the observations with ... Based on the international tidal gravity reference values at station Wuhan, the tidal gravity parameters, including the amplitude factors and phase differences are determined accurately by using the observations with three LaCoste-Romberg (LCR) gravimeters (G-589, ET-20 and ET-21) at stations Zhongshan and Changcheng in the Antarctic, respectively. The standard deviations of the determined amplitude factors of the main tidal waves are better than 0.5%. The amplitude of each tidal wave observed at station Zhongshan is much less than that of the same wave at station Changcheng. The differences of amplitude factors in the diurnal band (O1) at these two stations are less than 7% while those in the semi-diurnal band (M2) are larger than 40%. The influences of meteorology factors, such as atmospheric pressure and temperature, on the tidal gravity observations are very obvious. The oceanic loading effects on the tidal gravity are also very prominent. It is found that the amplitude of the final residual vector of every tidal wave reduces significantly after oceanic correction based on the Schwiderski(s global co-tides. However, because the local oceanic loading is not taken into account, the discrepancies of amplitude factors of wave O1 observed at Zhongshan from the corresponding values of theoretical tidal model are about 4%, and 9% at Changcheng. 展开更多
关键词 南极 中山站 长城站 重力潮汐观测 国际重力潮汐基准 理论潮汐模型
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On a Method of Climatological Observations Processing
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作者 Shamil Iliasov 《Journal of Environmental Science and Engineering(B)》 2013年第12期723-727,共5页
The task of climate observation data processing is central to the quality of an assessment of future climate change impact. The current state-of-the-art is based on the long-running observation records of the meteorol... The task of climate observation data processing is central to the quality of an assessment of future climate change impact. The current state-of-the-art is based on the long-running observation records of the meteorological stations. However, it is common for the developing states to have only relatively short and/or intermittent record histories. The issue becomes even more aggravated under an effort to assess the climatic trends for specific territories with few meteorological stations. The paper offers a simple and effective technique to handle the climate observations; the technique makes the most complete use of an available data set by counting the data provided by all meteorological stations including those with short records and omissions. The method is based on numeric differentiation of source data samples. 展开更多
关键词 Climate change meteorological station observation data processing trends.
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Planning Study on National Power Grid Interconnection Centered on Three Gorges Hydropower Station
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作者 Zhou Xiaoqian(President, China Power Crid Construction Corporation) 《Electricity》 1999年第2期2-3,共2页
关键词 Planning Study on National Power Grid Interconnection centered on Three Gorges Hydropower station GRID
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The Theoretical Principles of the Body-Centered Therapy to Promote Affective Attunement in Children with Autism Spectrum Disorder
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作者 Magda Di Renzo 《Journal of Behavioral and Brain Science》 2017年第12期545-556,共12页
Background: The roots of autism spectrum disorders become evident in first attunement mechanisms between mother and child that allow a first level of mentalizing. Neurosciences and current developmental theories confi... Background: The roots of autism spectrum disorders become evident in first attunement mechanisms between mother and child that allow a first level of mentalizing. Neurosciences and current developmental theories confirm the existence of defensive mechanisms related to body and affectivity that psychodynamic theories had already highlighted. Reading child’s behavior not only by administering tests but also through careful clinical observations allows a better understanding of the communication and social difficulties present in autistic children. The identification of the zone of proximal development can promote a therapeutic intervention that respects the individuality of the child and the specificity of his relational approach to the world. Conclusion: The paper presents the theoretical principles of a body-centered therapy to promote the attunement processes necessary to activate cognitive resources. 展开更多
关键词 AUTISM SPECTRUM DISORDERS Body-centered THERAPY AFFECTIVE attunement MENTALIZING Clinical observation
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Temperature variations at the Great Wall and Zhongshan stations 被引量:1
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作者 BIAN LinGen MA YongFeng +1 位作者 LU ChangGui LU LongHua 《Chinese Journal of Polar Science》 2011年第1期42-48,共7页
Surface meteorological observations have been carried out at the Great Wall station (GW) and Zhongshan station (ZS) from 1984 to 2008 and from 1989 to 2008 respectively. The variation in mean air temperature and i... Surface meteorological observations have been carried out at the Great Wall station (GW) and Zhongshan station (ZS) from 1984 to 2008 and from 1989 to 2008 respectively. The variation in mean air temperature and its trends are derived from the meteorological observation data recorded at both stations. The warming rate of the annual mean temperature at GW is similar to that at Bellingshausen station, which is about 3 km distant. Thus, the warming trend is representative of the King George Island region. The warming rate of ZS is less different from that at Davis station,which is about 100 km from ZS. It can be said that the meteorological data recorded at both stations are representative of the regions of the King George Island and east coast of the Antarctic. 展开更多
关键词 Chinese Antarctic station Meteorological observation air temperature TREND
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Simulation analysis of a method to improve data-transmission performance of Nanshan 26 m Radio Telescope based on Software-Defined Networks 被引量:1
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作者 Jie Wang Hai-Long Zhang +5 位作者 Na Wang Xin-Chen Ye Wan-Qiong Wang Jia Li Meng Zhang Ya-Zhou Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第11期79-88,共10页
Data Center of Xinjiang Astronomical Observatory(XAO-DC)commenced operating in 2015,and provides services including archiving,releasing and retrieving precious astronomical data collected by the Nanshan 26 m Radio Tel... Data Center of Xinjiang Astronomical Observatory(XAO-DC)commenced operating in 2015,and provides services including archiving,releasing and retrieving precious astronomical data collected by the Nanshan 26 m Radio Telescope(NSRT)over the years,and realises the open sharing of astronomical observation data.The observation data from NSRT are transmitted to XAO-DC 100 km away through dedicated fiber for long-term storage.With the continuous increase of data,the static architecture of the current network cannot meet NSRT data-transmission requirements due to limited network bandwidth.To get high-speed data-transmission using the existing static network architecture,a method for reconstruction data-transmission network using Software-Defined Networks(SDN)is proposed.Benefit from the SDN’s data and control plane separation,and open programmable,combined with the Mininet simulation platform for experiments,the TCP throughput(of single thread)was improved by~24.7%,the TCP throughput(of multi threads)was improved by~9.8%,~40.9%,~35.5%and~11.7%.Compared with the current network architecture,the Latency was reduced by~63.2%. 展开更多
关键词 data transmission observation data data center virtual machine
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Spatio-Temporal Change of Atmospheric Precipitation on Territory of North-West of Ukraine 被引量:1
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作者 Budnik S.V. 《Journal of Atmospheric Science Research》 2019年第4期1-4,共4页
The direction of the trend of precipitation over time is an important characteristic for both theoretical and practical use.The presented study is devoted to the analysis of changes in the territory of the trend of pr... The direction of the trend of precipitation over time is an important characteristic for both theoretical and practical use.The presented study is devoted to the analysis of changes in the territory of the trend of precipitation over the year over time.At the present stage of climate change in the north-west of Ukraine,there is a general tendency to increase rainfall over the year.This trend is not the same across the territory and depends on the height and latitude of the area.The amount of precipitation varies both in space and in time,however,the distribution of the characteristics of the rains themselves(intensity,duration and others)continue to remain similar throughout the territory.The revealed features of changes in the amount of precipitation in space and time can be useful in studying the unevenness of wetting,forecasting floods,changes in erosion activity,etc. 展开更多
关键词 Precipitation characteristics TREND TERRITORY Meteorological station Long-term observations
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The spatial distribution of dark matter annihilation originating from a gamma-ray line signal 被引量:1
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作者 Tong-Suo Lu Tie-Kuang Dong Jian Wu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第5期520-526,共7页
The GeV-TeV -γ-ray line signal is the smoking gun signature of dark matter annihilation or decay. The detection of such a signal is one of the main targets of some space-based telescopes, including Fermi-LAT and the ... The GeV-TeV -γ-ray line signal is the smoking gun signature of dark matter annihilation or decay. The detection of such a signal is one of the main targets of some space-based telescopes, including Fermi-LAT and the upcoming missions CALET, DAMPE and Gamma-400. An important feature of γ-ray line photons that originate from dark-matter-annihilation is that they are concentrated at the center of the Galaxy. So far, no reliable γ-ray line has been detected by Fermi-LAT, and the upper limits on the cross section of annihilation into "y-rays have been reported. We use these upper limits to estimate the "maximal" number of -y-ray line photons detectable for Fermi- LAT, DAMPE and Gamma-400, and then investigate the spatial distribution of these photons. We show that the center of the distribution will usually be offset from the Galactic center (Sgr A*) due to the limited statistics. Such a result is almost indepen- dent of models of the dark matter distribution, and will render the reconstruction of the dark matter distribution with the γ-ray line signal very challenging for foreseeable space-based detectors. 展开更多
关键词 COSMOLOGY observations -- cosmology dark matter -- Galaxy center-- instrumentation detectors
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