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基于rs与GIS技术的分布式水文模型模拟径流变化刍议

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水土保持学报 2004年第4期18卷 12-15页

作者：李道峰刘昌明北京师范大学环境科学研究所水环境模拟国家重点实验室水沙科学教育部重点实验室

基于遥感和地理信息系统技术的分布式水文模型是目前水文模拟发展的主要方向。分析了分布式水文模型、遥感和地理信息系统技术在流域径流模拟过程中的结合点,并针对流域径流要素对土地覆被和气候变化响应过程为目的,讨论利用分布式水文... 详细信息

基于遥感和地理信息系统技术的分布式水文模型是目前水文模拟发展的主要方向。分析了分布式水文模型、遥感和地理信息系统技术在流域径流模拟过程中的结合点,并针对流域径流要素对土地覆被和气候变化响应过程为目的,讨论利用分布式水文模型研究土地覆被和气候变化下径流响应过程的一般方法。

关键词： rs技术 GIS技术分布式水文模型模拟径流变化

Symmetric carbon tetramers forming spin qubits in hexagonal boron nitride

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npj Computational Materials 2023年第1期9卷 407-416页

作者： Zsolt Benedek Rohit Babar Ádám Ganyecz Tibor Szilvási Örs Legeza Gergely Barcza Viktor Ivády Strongly Correlated Systems Lendület Research Group Wigner Research Centre for PhysicsPO Box 49H-1525 BudapestHungary MTA-ELTE Lendület“Momentum”NewQubit Research Group Pázmány PéterSétány 1/A1117 BudapestHungary Department of Chemical and Biological Engineering The University of AlabamaTuscaloosaAL 35487USA Institute for Advanced Study Technical University of MunichLichtenbergstrasse 2a85748 GarchingGermany Department of Physics of Complex Systems Eötvös Loránd UniversityEgyetem tér 1-3H-1053 BudapestHungary Department of Physics Chemistry and BiologyLinköping UniversitySE-58183 LinköpingSweden

Point defect quantum bits in semiconductors have the potential to revolutionize sensing at atomic ***,vacancy-related defects are at the forefront of high spatial resolution and low-dimensional *** the other hand,it is expected that impurity-related defect structures may give rise to new features that could further advance quantum sensing in low ***,we study the symmetric carbon tetramer clusters in hexagonal boron nitride and propose them as spin qubits for *** utilize periodic-DFT and quantum chemistry approaches to reliably and accurately predict the electronic,optical,and spin properties of the studied *** show that the nitrogen-centered symmetric carbon tetramer gives rise to spin state-dependent optical signals with strain-sensitive intersystem crossing ***,the weak hyperfine coupling of the defect to their spin environments results in a reduced electron spin resonance linewidth that can enhance sensitivity.

关键词： hexagonal boron quantum

A Distributed GIS and rs Information Comprehensive Analysis and Process System

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A Distributed GIS and RS Information Comprehensive Analysis ...

Optimal Design on the Magnetic Field of the High-speed Response Solenoid Valve

ICIG’2000 First International Conference on Image and Graphics--Image and Graphic Technology Toward 21st Century and Beyond

作者： Zhao Min , Ling Fugen, Lin Xinggang, Du Jing Tsinghua University, 100084 beijing,China Tianchen New Technology Development Co. 100085 beijing

An important trend in the development of GIS and rs is their permeation and integration. So, we integrated and developed a GIS/rs information comprehensive analysis and process system and made a comprehensive study on the architecture of distributed multiprocessor, data handling procedure and the design of fast data path from the point of promptness of comprehensive information process. We also approached the method and mechanism of the GIS/rs information comprehensive analysis and Process system through technological practices in GIS-aid rs image correction, rs automatically generating DEM as GIS information source, and GIS data generating composed maps.

关键词： distributed GIS and rs image process geographic process

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cnki会议

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厦门大学学报（自然科学版） 2002年第S1期41卷 160-161页

作者： TAO Gang, CHEN Hui-yan, JIN Ya-ying, HE Zhong-bo (Lab of Vehicle Electronic Engineering, School of Vehicle & Transportat ion Engineering, beijing Institute of Technology, beijing 100081, China)

As an integrated control unit that directly transfo rm s digital electric signals into analogy hydraulic signals, High-speed response solenoid valve (HSV) plays an important role in determining an electro-hydrauli c automatic system’s overall performance. In the process of designing an HSV, o ne should well understand that various soft magnetic material properties and geo metries greatly affect HSV’s magnetic field design that accordingly has a direc t influence on HSV’s electric performance. As an approach of improving HSV perf ormance, this paper presents an optimal design method on HSV’s magnetic field b y making a full consideration of the effects of various soft magnetic material a nd geometries. The proposed optimal design method, based on HSV’s three-dimens ion solid modeling with the PRO/E software, simplifying from the previous three -dimension solid model to the axially symmetric plane model of the magnetic fie ld and the consequent the magnetic finite element method simulating within ANSYS analysis environment for obtaining accurate results on the distribution of HSV ’s magnetic field and flux-line as well as the magnetic force, can achieve lar ger magnetic force and lower power of an HSV by adjusting the structure paramete rs of the solenoid valve and selecting various soft magnetic materials which are of different B-H (flux density vs. field intensity) curves. Considering the no nlinearity and saturation of various soft magnetic materials, this paper process es the nonlinearity simulated calculation and experiment measure of three soft m agnetic materials and different structure parameters. The comparison of the simu lating and experimenting results proves that the simulating calculation and the proposed optimal design method are effective in HSV’s designing and its perform ance prediction. The researching results show that, for HSV’s designing, the pr oposed optimal design method can well simulate HSV’s the magnetic field, enhanc e the reliability and

关键词： modeling magnetic field simulation optimal des ign

Polishing technology of surface for diamond film using the method of laser ablation

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Chinese Science Bulletin 1997年第23期42卷 2010-2013页

作者： Gu, CZ Jin, ZS Wang, YG Zhuang, rs Lu, XY Zhao, ST Zou, GT Jilin Univ State Key Lab Superhard Mat Changchun 130023 Peoples R China

THE chemical vapor deposition (CVD) methods have been developed so much in the past tenyears that it has become less expensive to deposit a thick CVD diamond film than to polish thediamond. The polycrystalline films nomnally exhibit a pronounced roughness because there arelots of large pointed grains on the surface of the films. On the other hand, the thickness unityof diamond film is poor because of the effects of deposition condition, especially for those syn-thesized by the methods of hot filament CVD (HFCVD) and electron assistant CVD(EACVD). Poor thickness unity and rough surface of thick diamond film limits their poten-

关键词： diamond film laser ablation polishing of surface.

Responses of soil respiration in non-growing seasons to environmental factors in a maize agroecosystem,Northeast China

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Chinese Science Bulletin 2010年第24期55卷 2723-2730页

作者： LI RongPing1,2,3, ZHOU GuangSheng1,4 & WANG Yu1,3 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, beijing 100093, China 2 Institute of Atmospheric Environment, China Meteorological Administration, Shenyang 110016, China 3 Graduate University of Chinese Academy of Sciences, beijing 100049, China 4 Chinese Academy of Meteorological Sciences, beijing 100081, China State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China Institute of Atmospheric Environment China Meteorological Administration Shenyang 110016 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Chinese Academy of Meteorological Sciences Beijing 100081 China

Based on continuous three-year measurements (from 2004 to 2007) of eddy covariance and related environmental factors, environmental controls on variation in soil respiration (rs) during non-growing season were explored in a maize agroecosystem in Northeast China. Our results indicated that during non-growing seasons, daily rs was 1.08-4.08 g CO2 m-2 d-1, and the lowest occurred in late November. The average rs of non-growing season was 456.06 ± 20.01 g CO2 m-2, accounting for 11% of the gross primary production (GPP) of the growing season. Additionally, at monthly scale, the lowest value of rs appeared in January or February. From the beginning to the end of non-growing season, daily rs tended to decrease first, and then increase to the highest. There was a significant quadratic curve relationship between rs and soil temperature at 10 cm depth when soil temperature was more than 0°C (Prs (Prs was established by coupling soil temperature and moisture, which could explain the rate of up to 53%-79%. Meanwhile, the standard error of regression estimation between the values of prediction and observation for rs could reach 2.7%-11.8%. rs in non-growing season can account for 22.4% of rs in growing season, indicating that it plays a critical role in assessing the carbon budget in maize agroecosystem, Northeast China.

关键词：中国东北地区农田生态系统生长季节土壤呼吸环境因素玉米土壤含水量反应

基于GNSS/GIS/rs集成技术的铁路列车运营监控

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计算机工程与应用 2003年第23期39卷 224-228页

作者：张李勇张飞舟北京航空航天大学自动化科学及电气工程学院北京100083 北京大学遥感与地理信息系统研究所北京100871

文章阐述了全球导航卫星系统GNSS(GlobalNavigationSatelliteSystem)、地理信息系统GIS(GeographicInfor-mationSystem)、遥感rs(RemoteSensing)技术的基本特征、相互关系及其集成基本方式。针对我国目前智能铁路运输系统发展趋势,运用GNSS/GIS/rs集成技术,进行铁路列车运营监控探讨性研究。该集成导航技术将卫星导航、地理信息系统以及遥感技术融合在一起,可实现铁路运输管理“自动化”、列车行驶“智能化”,减少运输服务时间,提高铁路运输整体效益,并且具有良好的实用价值。

关键词：全球定位系统全球导航卫星系统地理信息系统遥感铁路智能交通系统运营监控

Monitoring of Pinus massoniana spatial pattern changes based on rs and GIS techniques

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Forest Ecosystems 2008年第1期10卷 32-35页

作者： WANG Lei, HUANG Hua-guo, ZHANG Xiao-li*, LUO You-qing, SHI Juan Key Laboratory for Silviculture and Conservation of Ministry of Education, beijing Forestry University, beijing 100083, P. R. China Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry University Beijing 100083 P. R. China

Our research focused on Pinus massoniana information extracted from remote sensing images based on the knowledge detection and decision tree algorithm and established a spatial pattern model, combining quantitative theoretical ecology with remote sensing (rs) and geometric information system (GIS) techniques. Applying information extraction methods and a spatial pattern model, we studied P. massoniana spatial patterns changes before and after the invasion by pine wood nematode (Bursaphelenchus xylophilus) in Fuyang and Zhoushan counties, Zhejiang Province, east China. The P. massoniana spatial patterns are clustering, whether the invasion happened or not. But the degree of clustering is different. Our results show good agreement with field data. Applying the results, we analyzed the relationship between spatial patterns and the invasion level. Then we drew the elementary conclusion that there are two kinds of patterns for pine wood nematode to spread: continuous and discontinuous diffusion. This approach can help monitor and evaluate the changes in ecological systems.

关键词： Bursaphelenchus xylophilus invasion remote sensing GIS information extraction Pinus massoniana spatial pattern

Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion

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Science China Earth Sciences 2006年第6期49卷 632-640页

作者： QIN Jun1, YAN Guangjian1, LIU Shaomin1, LIANG Shunlin2, ZHANG Hao1, WANG Jindi1 & LI Xiaowen1 1. State Key Laboratory of Remote Sensing Science, School of Geography and Remote Sensing, Research Center for rs&GIS, beijing Normal University, beijing 100875, China 2. Department of Geography, 2181 Lefrak Hall, University of Maryland, College Park, MD20742, USA 1. State Key Laboratory of Remote Sensing Science School of Geography and Remote Sensing Research Center for RS&GIS Beijing Normal University Beijing 100875 China 2. Department of Geography 2181 Lefrak Hall University of Maryland College Park MD20742 USA

The use of a priori knowledge in remote sensing inversion has great implications for ensuring the stability of inversion process and reducing uncertainties in retrieved results, especially under the condition of insufficient observations. Common optimization algorithms have difficulties in providing posterior distribution and thus cannot directly acquire uncertainties in inversion results, which is of no benefit to remote sensing application. In this article, ensemble Kalman filter (EnKF) has been introduced to retrieve surface geophysical parameters from remote sensing observations, which has the capability of not merely obtaining inversion results but also giving its posterior distribution. To show the advantage of EnKF, it is compared to standard MODIS AMBRALS algorithm and highly effi-cient global optimization method SCE-UA. The inversion abilities of kernel-driven BRDF models with different kernel combinations at several main cover types are emphatically discussed when observa-tions are deficient and a priori knowledge is introduced into inversion.

关键词： remote sensing inversion, a priori knowledge, posterior distribution, ensemble kalman filter, BRDF, kernel-driven model, albedo.