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| 1 | 北斗导航系统卫星激光测距综述显示文摘Satellite laser ranging(SLR)is an unambiguous measurement technique and generates high accuracy satellite orbit data.All satellites in the BeiDou navigation satellite system(BDS)carried laser retro-reflector arrays(LRAs),so they can be tracked by ground SLR stations in order to provide the accurate observation data.The Shanghai astronomical observatory(SHAO)designed the LRAs,and also developed the dedicated SLR systems using a 1 m-aperture telescope and a transportable cabin-based SLR system with a telescopes of 60 cm aperture.These enable BDS satellite ranging during daytime and nighttime with centimeter-level precision,allowing highly accurate estimations of satellite orbits.Moreover,some of the BDS satellites are also equipped with laser time transfer(LTT)payloads,which were developed by the SHAO and China Academy of Space Technology(CAST),providing a highly accurate time comparison between the satellites and ground clocks.This paper describes the dedicated SLR system and the design of the LRAs for BDS satellites,as well as global SLR measurements.The SLR tracking data is used for evaluating the orbit accuracy of BDS satellites and broadcast ephemeris,with an accuracy of less than 1 m.The LTT measurements to BDS satellites for a single shot have a precision of approximately 300 picoseconds,with a time stability of 20 picoseconds in 500 s. | ZHANG Haifeng LONG Mingliang YANG Huafeng MENG Wendong CHENG Zhi’en DENG Huarong ZHANG Zhongping ZHANG A’li | 2020 | Aerospace China2020，21，4： | 4 |
| 2 | A Feasible Atmospheric Correction Method to TM Image显示文摘In this paper, an atmospheric correction method to TM image is presented, which can simulate the atmospheric correction parameters, such as optical depth, sky radiance and path radiance at the time the satellite passes,by using interpolation among local meteorological records, parameterization models and dark pixels. The TM image of the Nanjing area in China was corrected by this method. For analyzing the accuracy of this method, the calculated reflectance, apparent reflectance and ground measured reflectance were compared. NDVI before and after atmospheric cor- rection were also compared. The results show that the method is applicable and efficient in the visible to near infrared band of TM image. In order to improve the accuracy of the method, the infrared spectrum measured data for the two other bands of TM image are required in future field investigations. The method is suitable to many other satellite optical remote sensing images with the same or similar spectral characteristics of TM images. | ZHENG Wei LIU Chuang ZENG Zhi-yuan LONG En | 2007 | Journal of China University of Mining and Technology2007，17，1： | 3 |
| 3 | Significant loss of soil inorganic carbon at the continental scale显示文摘Widespread soil acidification due to atmospheric acid deposition and agricultural fertilization may greatly accelerate soil carbonate dissolution and CO_(2) release.However,to date,few studies have addressed these processes.Here,we use meta-analysis and nationwide-survey datasets to investigate changes in soil inorganic carbon(SIC)stocks in China.We observe an overall decrease in SIC stocks in topsoil(0-30 cm)(11.33 g C m^(-2)yr^(-1))from the 1980s to the 2010s.Total SIC stocks have decreased by∼8.99±2.24%(1.37±0.37 Pg C).The average SIC losses across China(0.046 Pg C yr^(-1))and in cropland(0.016 Pg C yr^(-1))account for∼17.6%-24.0%of the terrestrial C sink and 57.1%of the soil organic carbon sink in cropland,respectively.Nitrogen deposition and climate change have profound influences on SIC cycling.We estimate that∼19.12%-19.47%of SIC stocks will be further lost by 2100.The consumption of SIC may offset a large portion of global efforts aimed at ecosystem carbon sequestration,which emphasizes the importance of achieving a better understanding of the indirect coupling mechanisms of nitrogen and carbon cycling and of effective countermeasures to minimize SIC loss. | Xiao-Dong Song Fei Yang Hua-Yong Wu Jing Zhang De-Cheng Li Feng Liu Yu-Guo Zhao Jin-Ling Yang Bing Ju Chong-Fa Cai Biao Huang Huai-Yu Long Ying Lu Yue-Yu Sui Qiu-Bing Wang Ke-Ning Wu Feng-Rong Zhang Ming-Kui Zhang Zhou Shi Wan-Zhu Ma Gang Xin Zhi-Ping Qi Qing-Rui Chang En Ci Da-Gang Yuan Yang-Zhu Zhang Jun-Ping Bai Jia-Ying Chen Jie Chen Yin-Jun Chen Yun-Zhong Dong Chun-Lan Han Ling Li Li-Ming Liu Jian-Jun Pan Fu-Peng Song Fu-Jun Sun Deng-Feng Wang Tian-Wei Wang Xiang-Hua Wei Hong-Qi Wu Xia Zhao Qing Zhou Gan-Lin Zhang | 2022 | National Science Review2022，9，2： | 2 |
| 4 | Synthesis of (+) 8-O-Cinnamyl-p-chlorogoniotriol and its Analogues显示文摘(+) 8-O-Cinnamyl-p-chlorogoniotriol (p-chlorohowjinol A) and its analogues have beensynthesized in nine steps from a-D-glucoheptonic-r-lactone. Pharmacological tests showed thatmost of the compounds possessed antitumor activities toward tumor cell in | Hong CHEN Long En ZHOU Yan Jun ZHANG De Quan YU(Institute of Meteria Medica Chinese Academy of Medical Sciences &Peking Union Medical College. Beijing 100050) | 1999 | Chinese Chemical Letters1999，10，6： | 1 |
| 5 | Distribution Characteristics of Spermophilus dauricus in Manchuria City in China in 2015 through ‘3S' Technology显示文摘Plague is a virulent infectious disease in China.In this study,‘3S’technology was used to perform spatial autocorrelation analysis and spatial interpolation analysis for Spermophilus dauricus(S.Dauricus,a species of ground squirrel)captured in Manchuria City in 2015.The results were visually inspected.During the two-month(May to July)plague surveillance in 2015,198 S.dauricus individuals were captured in the study area | FAN Long Xing WU En Qi QU Xiao Chen LIU Chao NING Bao An LIU Ying | 2016 | Biomedical and Environmental Sciences2016，29，8： | 1 |
| 6 | Hourly classified identifications: the annual relative variation rates (RVRs) are approximate in different cities for the same building with the same shading coefficient 显示文摘 | J LONG En - shen Zang Zi - xuan | 2005 | Building and Environment2005，40，4： | 1 |
| 7 | Spatiotemporal wavelet analysis for functional MRI显示文摘 | Long C Brown EN Manoach D | 2004 | Neuroimage2004，23，2： | 1 |
| 8 | Response of droplet parameters to liquid viscosity in the flow field of an air-blast sprayer显示文摘The physical properties of sprayed droplets such as viscosity affect their deposition on the target.In order to understand the response characteristics of droplet parameters to the viscosity of a spray solution,a three-dimensional model of the external flow field of an air-blast sprayer based on computational fluid dynamics(CFD)was established according to the actual spray range and the sprayer duct structure.The change rules of droplet diameter and droplet density with distance under different viscosities of the spray solution in the flow field were obtained through numerical solution of the CFD model.The reliability of the model was verified by a chi-squared test comparing the numerical calculations with the results of field experiments.The results showed that the change rule of droplet parameters in an airflow field under different values of the spray solution viscosity was consistent.With the increase in the axial distance,the droplet size decreased initially,then increased,and finally decreased,while the droplet density gradually decreased.Moreover,the greater the spray solution viscosity,the shorter the conveying distance of the droplets in the axial direction,although viscosity was helpful in reducing the droplet drift.In addition,at the same axis distance,with the increased viscosity of the spray solution,the droplet size increased,and the sedimentation of the droplets was more rapid,while the density of the droplets decreased.The results provided a new framework for the study of air-blast spraying technology and serve as a reference for the optimization of the sprayer structure and the preparation method for spray solutions. | Xi'en Zhou Bing Xiahou Long Zhang Daozong Sun Xiuyun Xue Qiufang Dai Shuran Song | 2023 | International Journal of Agricultural and Biological Engineering2023，16，5： | 0 |
| 9 | Orientations of Rare-earth-containing Heteropolyoxometalates with Different Sizes in the Interlayer of Synthetic Multibilayer Films显示文摘Three rare-earth-containing heteropolyoxometalates with different sizes, Na9[Eu(W5 O18)2], K13[Eu(SiW11O39)2], and K17[Eu(P2W17O61)2], have been incorporated by self-assembly into the interlayer of synthetic multibilayer films of dimethyldioctadecylammonium chloride and exhibited different orientations. | Yong Hui WANG, Xin Long WANG, Chang Wen HU*, En Bo WANG Institute of Polyoxometalate Chemistry, Faculty of Chemistry, Northeast Normal University, Changchun 130024 | 2002 | Chinese Chemical Letters2002，13，9： | 0 |
| 10 | A Study on Human-Computer Interaction Mechanism in an Intelligent Tutoring System显示文摘Discussion is a common and important learning process.Involvement of a virtual agent can provide adaptive support for the discussion process.Argumen-tative knowledge construction is beneficial to learners’acquisition of knowledge,but the effectiveness of argumentative scaffolding in existing studies is not consistent.Based on an intelligent discussion system,a total of 47 undergraduate students took part in the experiment and they were assigned to three different conditions:content-related plus content-independent scaffolding condition,content-related scaffolding condition,and the control condition.Under the content-related and content-independent scaffolding condition,the computer agent provided an idea from semantically different categories(content-related scaffolding)according to the automatic categorization of the current contributions,and further inquired the participants about their attitudes and reasons(content-independent scaffolding).Under the condition of content-related scaffolding condition,the virtual agent only provided semantically different viewpoints.Under the control condition,the subjects expressed their opinion independently without the participation of the virtual agent.Findings revealed that compared with the control group,when the virtual agent provided semantically different ideas(content-related scaffolding),the discussion breadth(number of categories)was improved and the subjects felt that they had a more comprehensive understanding of the problem.Compared with the content-related scaffolding condition,when the virtual agent provided semantically different ideas and further asked about the attitudes and reasons,the subjects expressed more agreement with these views,but mentioned fewer categories during the discussion.This study suggests that the content-related scaffolding can facilitate the cognitive processing effect relevant to the topic of discussion.When the content independent scaffolding is added,it can promote the argumentative processing,but may have a negative effect on the cognitive processing related to the topic discussed. | GAO Hongli YANG Lei XU Sheng LONG Zhou LIU Kai HU Xiang’en | 2022 | Frontiers of Education in China2022，17，1： | 0 |
| 11 | Dynamic evaluation of a scaled-down heat pipe-cooled system during start-up/shut-down processes using a hardware-in-the-loop test approach显示文摘Micro-mobile heat pipe-cooled nuclear power plants are promising candidates for distributed energy resource power genera-tors and can be flexibly deployed in remote places to meet increasing electric power demands.However,previous steady-state simulations and experiments have deviated significantly from actual micronuclear system operations.Hence,a transient analysis is required for performance optimization and safety assessment.In this study,a hardware-in-the-loop(HIL)approach was used to investigate the dynamic behavior of scaled-down heat pipe-cooled systems.The real-time features of the HIL architecture were interpreted and validated,and an optimal time step of 500 ms was selected for the thermal transient.The power transient was modeled using point kinetic equations,and a scaled-down thermal prototype was set up to avoid mod-eling unpredictable heat transfer behaviors and feeding temperature samples into the main program running on a desktop PC.A series of dynamic test results showed significant power and temperature oscillations during the transient process,owing to the inconsistency of the rapid nuclear reaction rate and large thermal inertia.The proposed HIL approach is stable and effective for further studying of the dynamic characteristics and control optimization of solid-state small nuclear-powered systems at an early prototyping stage. | Jiao‑Long Deng Tian‑Shi Wang En‑Ping Zhu Shuo Yuan Xiao‑Jing Liu Xiang Chai | 2023 | Nuclear Science and Techniques2023，34，11： | 0 |
| 12 | THE CHEMICAL STRUCTURE OF HYPODEMAPYRAZIN显示文摘A novel alkaloid named Hypodemapyrazine was isolated from the whole plantof a fern,Hypodematium sinense Iwatsuki. Its chemical structure has been elucidated to be a novel skeleton containing ahydro-pyrazine by means of UV, IR, 1H-NMR, 13C-NMR and HRMS spectroscopy. | Ying Hua LU Ya Min CHEN Xin Min WUN Hong En WANG Cun Shen MA Rong Long ZHU De Quan YU Jining Medical College, Jining. Shandong 272113 Institute of Materia Medica, Chinese Academy of Medical Sciences, Bejing 100050 | 1993 | Chinese Chemical Letters1993，4，7： | 0 |
| 13 | Removal of Stripes in Remote Sensing Images Based on Statistics Combined with Image Enhancement显示文摘A method to remove stripes from remote sensing images is proposed based on statistics and a new image enhancement method.The overall processing steps for improving the quality of remote sensing images are introduced to provide a general baseline.Due to the differences in satellite sensors when producing images,subtle but inherent stripes can appear at the stitching positions between the sensors.These stitchingstripes cannot be eliminated by conventional relative radiometric calibration.The inherent stitching stripes cause difficulties in downstream tasks such as the segmentation,classification and interpretation of remote sensing images.Therefore,a method to remove the stripes based on statistics and a new image enhancement approach are proposed in this paper.First,the inconsistency in grayscales around stripes is eliminated with the statistical method.Second,the pixels within stripes are weighted and averaged based on updated pixel values to enhance the uniformity of the overall image radiation quality.Finally,the details of the images are highlighted by a new image enhancement method,which makes the whole image clearer.Comprehensive experiments are performed,and the results indicate that the proposed method outperforms the baseline approach in terms of visual quality and radiation correction accuracy. | Xiaofei QU Weiwei ZHAO En LONG Meng SUN Guangling LAI | 2023 | Journal of Geodesy and Geoinformation Science2023，6，1： | 0 |
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