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A study on the early-warning technique concerning debris flow disasters

Journal of Geographical Sciences 2002年第3期12卷 363-370页

作者： ZHOU Jinxing, WANG Lixian, XIE Baoyuan, FEI Shimin, WANG Xilin (1. Inst. of Forestry Research, Chinese Academy of Forestry Science, beijing 100091, china 2. College of resource & {3., beijing Forestry university, beijing 100083. china) Inst of Forestry Research Chinese Academy of Forestry Science 北京 100091 College of resource & environment Beijing Forestry University 北京 100083

According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destructive strength, the debris flow torrent, high sand-carrying capacity flush flood torrent and common flush flood by the techniques. In this paper, the classification indices system and the quantitative rating methods are presented. Based on torrent classification, debris flow torrent hazard zone mapping techniques by which the debris flow disaster early-warning object can be ascertained accurately are identified. The key techniques of building the debris flow disaster neural network (NN) real time forecasting model are given detailed explanations in this paper, including the determination of neural node at the input layer, the output layer and the implicit layer, the construction of knowledge source and the initial weight value and so on. With this technique, the debris flow disaster real-time forecasting neural network model is built according to the rainfall features of the historical debris flow disasters, which includes multiple rain factors such as rainfall of the disaster day, the rainfall of 15 days before the disaster day, the maximal rate of rainfall in one hour and ten minutes. It can forecast the probability, critical rainfall of eruption of the debris flows, through the real-time rainfall monitoring or weather forecasting. Based on the torrent classification and hazard zone mapping, combined with rainfall monitoring in the rainy season and real-time forecasting models, the debris flow disaster early-warning system is built. In this system, the gis technique, the advanced international software and hardware are applied, which makes the system’s performance steady with good expansibility. The system is a visual information system that serves management and decision-making, which can facilitate timely inspect of the variation of the torrent type

关键词： debris flows disaster early-warning technique torrent classification mapping of the hazard zones

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Comments on scaling effect of reciprocity in BRDF study

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Progress in Natural Science:Materials International 2004年第3期 95-96页

作者： ZHAO Hongrui* and WANG Jindi(Research Center for Remote Sensing and gis, Department of Geography, beijing Normal university, beijing key laboratory for Remote Sensing of environment and Digital Cities, beijing 100875, china) ResearchCenterforRemoteSensingandgis DepartmentofGeographyBeijingNormalUniversityBeijingKeyLaboratoryforRemoteSensingofEnvironmentandDigitalCitiesBeijing100875China

Reciprocity principle is a common theory in electromagnetics and optics. It is also one of the general principles of the radiation transformation theory. However, in many remote sensing studies, this principle cannot be always supported by experimental data, especially when the scaling effect of the remote sensing image pixel is considered. The debate over the issue of whether the reciprocity principle can be used as a fundamental standard in evaluating the effectiveness of remote sensing observations has lasted for years. Using geometrical optics model, Li and Wan proved the existence of the scaling effect in applying the reciprocity principle to a remote sensing image pixel in 1998. In 2002, Snyder challenged Li’s proof, and attempted to prove that reciprocity principle is universally valid without any scale limitation. In this paper, we will argue with Snyder’s theory and point out that Snyder’s theory had neglected an important condition used in Li’s proof and, as a result, drawn the wrong conclusion. Here we will restate Li’s condition in his demonstration and offer a further proof to verify that reciprocity principle cannot be applied unconditionally to the study of bi directional reflectance distribution function (BRDF) of land surfaces in field or satellite remote sensing observation scale.

关键词： BRDF reciprocity scaling effect.

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Resistance to chemical attack of bittern-resisting cement in high-bittern environment

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International Journal of Minerals,Metallurgy and Materials 2005年第5期 87-93页

作者： Yunbing Hou, Bingwen Wang, Yu Chen, Botao Zhang, and Lin Yu School of resource & Safety Engineering, china university of Mining & Technology ({3.), {3. 100083. china

A new kind of bittern-resisting cement (BRC) was introduced. This material is based on the ternary cementitious system of clinker containing C4A3.S phase, high-activity ground granulated blast-furnace slag (GGBFS) and fly ash (FA). The hydration proc- ess and the hydrated products of BRC were studied by means of XRD, TG-DTA and SEM, and the resistance to chemical attack of BRC in high-bittern environment was also examined. The corrosion experiment in seven kinds of brines proved that BRC exhibits an excellent resistance to chemical attack of bittern. The corrosion resistance factors were calculated and all of them were greater than 0.96. It showed that BRC totally controls the cement-based material corrosion in brines from four aspects: (1) making full use of the dominant complementation effect of mineral materials; (2) diminishing the hydrated products easy to be attacked; (3. improving the microstructure of hardened cement mortar; (4) degrading the chemical attack of bittern.

关键词： bittern-resisting cement ternary cementitious system high-activity mineral materials resistance to chemical attack bit- tern corrosion resistance factor corrosion mechanism

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Loose architecture of multi-level massive geospatial data based on virtual quadtree

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Science china(Technological Sciences) 2008年第S1期51卷 114-123页

作者： YANG ChongJun,WU Sheng,REN YingChao,FU Li,ZHANG FuQing,WANG Gang,TAN Jian,LIU DongLin,MA ChaoJi & LIANG Li State key laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal {3.,beijing 100101,china 1. State key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

This paper proposed a virtual quadtree (VQT) based loose architecture of multi-level massive geospatial data for integrating massive geospatial data dispersed in the departments of different hierarchies in the same sector into a unified gis (Geographic Information System) platform. By virtualizing the nodes of the quad-tree,the VQT separates the structure of data organization from data storage,and screens the difference between the data storage in local computer and in the re-mote computers in network environment. And by mounting,VQT easily integrates the data from the remote computers into the local VQT so as to implement seam-less integration of distributed multi-level massive geospatial data. Based on that mode,the paper built an application system with geospatial data over 1200 GB distributed in 12 servers deployed in 12 cities. The experiment showed that all data can be seamlessly rapidly traveled and performed zooming in and zooming out smoothly.

关键词： massive geospatial data virtual quadtree loose architecture

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Effects of Amino Acids Replacing Nitrate on Growth,Nitrate Accumulation,and Macroelement Concentrations in Pak-choi (Brassica chinensis L.)

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Pedosphere 2007年第5期17卷 595-600页

作者： WANG Hua-Jing WU Liang-Huan WANG Min-Yan ZHU Yuan-Hong TAO Qin-Nan ZHANG Fu-Suo Ministry of Education key laboratory of environmental Remediation and Ecosystem Health College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 （China） College of Geography and resource Sciences Sichuan Normal University Chengdu 610066 （China） Department of Crop and Soil Sciences the Pennsylvania State University （USA） College of resources and environment China Agricultural University Beijing 100094 （China）

A hydroponic experiment was carried out to determine the influence of replacing 20% of nitrate-N in nutrient solutions with 20 individual amino acids on growth, nitrate accumulation, and concentrations of nitrogen （N）, phosphorus （P）, and potassium （K） in pak-choi （Brassica chinensis L.） shoots. When 20% of nitrate-N was replaced with arginine （Arg） compared to the full nitrate treatment, pak-choi shoot fresh and dry weights increased significantly （P ≤ 0.05）, but when 20% of nitrate-N was replaced with alanine （Ala）, valine （Val）, leucine （Leu）, isoleucine （Ile）, proline （Pro）, phenylalanine （Phe）, methionine （Met）, aspartic acid （Asp）, glutamic acid （Glu）, lysine （Lys）, glycine （Gly）, serine （Ser）, threonine （Thr）, cysteine （Cys）, and tyrosine （Tyr）, shoot fresh and dry weights decreased significantly （P ≤ 0.05）. After replacing 20% of nitrate-N with asparagine （Asn） and glutamine （Gin）, shoot fresh and dry weights were unaffected. Compared to the full nitrate treatment, amino acid replacement treatments, except for Cys, Gly, histidine （His）, and Arg, significantly reduced （P ≤0.05） nitrate concentrations in plant shoots. Except for Cys, Leu, Pro, and Met, total N concentrations in plant tissues of the other amino acid treatments significantly increased （P ≤ 0.05）. Amino acids also affected total P and K concentrations, but the effects differed depending on individual amino acids. To improve pak-choi shoot quality, Gln and Asn, due to their insignificant effects on pak-choi growth, their significant reduction in nitrate concentrations, and their increase in macroelement content in plants, may be used to partially replace nitrate-N.

关键词： amino acids growth N P and K nitrate accumulation pak-choi

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Establishing Forest Landscape resources Information System Based on 3. Technique

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Chinese Forestry Science and Technology 2003年第1期2卷 71-77页

作者： ZHANG Zhifeng SHI Tongguang GONG HuiliThe key lab of resource and environment {3., capital Normal university. beijing, 10003.2 The department of civil engineering, Shandong Institute of Architecture & Engineering, Jinan ,250014

The application of Geographic Information System(gis), Remote Sensing(RS) and Global Position System(GPS) in the research of forest landscape is outlined in this paper. The integration of the 3. technique is also described. In the 3. system, RS is used to obtain the various information of forest landscape. GPS is used to obtain the ground data of orientation and guide the people to the different places. And gis is used in information management and processing.

关键词： gis RS GPS FLRIS

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基于PS-DR-DP理论模型的区域资源环境承载力综合评价

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地理学报 2019年第2期74卷 340-352页

作者：王亮刘慧中国科学院地理科学与资源研究所中国科学院区域可持续发展分析与模拟重点实验室北京100101 中国科学院大学资源与环境学院北京100049 北京师范大学地理科学学部北京100875

资源环境承载力状态评价研究成果众多,研究视角多侧重于"压力—状态—响应"模型的传统途径。本文构建了区域资源环境承载力综合评价框架体系,通过建立"PS-DR-DP"正六边形相互作用力理论模型,将资源环境承载力分解为"压力—支撑力""破坏... 详细信息

资源环境承载力状态评价研究成果众多,研究视角多侧重于"压力—状态—响应"模型的传统途径。本文构建了区域资源环境承载力综合评价框架体系,通过建立"PS-DR-DP"正六边形相互作用力理论模型,将资源环境承载力分解为"压力—支撑力""破坏力—恢复力""退化力—提升力"三对相互作用力,分别对应资源支撑能力、环境容量和风险灾害抵御能力,根据不同作用力大小变化所引起的六边形的形状和面积的变化综合测度区域资源环境承载力状态的变化。基于上述理论模型,采用分类排列多边形图示法,研究了北京市2010-2015年资源环境承载力状态的变化。结果表明,2010-2015年北京市资源环境承载力趋于理想承载状态。2010年正向因子综合承载作用力与负向因子综合承载作用力的比值为1.0143.比值大于1,区域承载状态较好;而2015年该比值为1.1411。与2010年相比,2015年北京市资源环境承载状态相对更佳。2015年相比较于2010年,负向因子作用力均减弱,正向因子综合作用力增强。2015年人口规模为2171万,承载贡献均值为0.7025,进入最佳承载门槛,且仍具有进一步承载的空间。研究结论对北京市2020年人口规模控制在23.0万以内提供了理论支撑。

关键词：综合承载力 PS-DR-DP模型人口规模北京市

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Crop Yield and Soil Responses to Long-Term Fertilization on a Red Soil in Southern china

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Pedosphere 2009年第2期19卷 199-207页

作者： ZHANG Hui-Min WANG Bo-Ren XU Ming-Gang FAN Ting-Lu key laboratory of Plant Nutrition and Nutrient Cycling Ministry of Agriculture of China and Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Department of resource and environment Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China Department of Agronomy Henan University of Science and Technology Luoyang 471003 China

A 15-year fertilization experiment with different applications of inorganic N,P and K fertilizers and farmyard manure (M)was conducted to study the yield and soil responses to long-term fertilization at Qiyang,Hunan Province,china. Average grain yields of wheat and corn(1 672 and 5 111 kg ha-1,respectively)for the treatment NPKM were significantly higher than those(405 and 3.0 kg ha-1)of the unfertilized control and single inorganic fertilizer *** with the corresponding initial values of the experiment,all treatments showed a yield decline of 9 to 111 kg ha-1 year-1 in wheat and 3. to 260 kg ha-1 year-1 in corn,respectively,and a significant pH decline of 0.07 to 0.12 pH year?1,except for the treatments PK and *** long-term fertilization,the soil organic C,soil available P,exchangeable Ca2+ and Mg2+and available Cu2+and Zn2+contents were higher in the treatment NPKM than in the treatments applied with inorganic fertilizer *** to the treatment NPK,the treatment NPKM,where manure partially replaced inorganic N,had a positive impact on arresting the decline of soil *** improved grain yields of wheat and corn, suggesting that application of NPK fertilizer in combination with farmyard manure is important to maintain soil fertility and buffering capacity in red soil.

关键词： corn long-term fertilization red soil wheat yield

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Monitoring Glacier and Supra-glacier Lakes from Space in Mt. Qomolangma Region of the Himalayas on the Tibetan Plateau in china

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Journal of Mountain Science 2009年第3期6卷 211-220页

作者： YE Qinghua ZHONG Zhenwei KANG Shichang Alfred Stein WEI Qiufang LIU Jingshi key laboratory of Tibetan environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences (CAS) Beijing 100085 China State key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China International Institutefor Geo-Information Science and Earth Observation (ITC) PO Box 67500 AA Enschede The Netherlands

Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote sensing and Geographical Information System （gis） techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 3. years, with retreat dominating. The glacier retreat area was 3.23.km2 （or o.75 km^2 yr^-1 during 1974 and 1976, 8.68 km^2 （or 0.3. km^2 yr^-1 during 1976 and 1992, 1.44 km^2 （or 0.12 km^2 yr^-1） during 1992-2ooo. 1.14 km^2 （or 0.22 km^2 yr^-1 during 2000-2003. and 0.52 km^2 （or 0.07 km^2 yr^-1 during 2003.2008, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2 in 1974 increased to 0.71 km^2 in 2008, which was more than 13.times larger in the last 3. years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 5400 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.

关键词： Glacier lake Remote Sensing Mr. Qomolangma region Himalayas Tibetan Plateau

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Incremental Study Based on Support Vector Used to Anomaly Detection for Hyperspectral Imagery

Incremental Study Based on Support Vector Used to Anomaly De...

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2010 International Conference on Remote Sensing (ICRS 2010)

作者： Liyan Zhang1 Derong Chen2 Yonghua Sun1 1.key laboratory of 3. Information Acquisition and Application of the Ministry of Education key laboratory of Integrated Disaster Assessment and Risk Governance of the Ministry of Civil Affairs key laboratory of resource environment and gis of beijing. capital Normal university 2. College of Mechanical and Electrical Engineering beijing Institute of Technology beijing Peoples R china

While detecting anomalies in hyperspectral imagery with support vector data description （SVDD）, large numbers of operation was run because of the high dimension character of dataset and the complexity of background and the high miss rate was discovered because of the interfered background by interior anomalies. This paper used incremental support vector data description （ISVDD） method that samples are divided many sub- sample, and incremental study is designed to simplify the computation. On every sub-sample study, optimization is needed according of the support vectors obtained from above sub-sample and current sub-sample data. By the experiment on the HYMAP data, computation complexity of the algorithm decrease obviously and the computation speed increase highly under the similar detection effect compared with SVDD algorithm.

关键词： hyperspectral imagery anomaly detection incremental support vector data description

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