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141.
National and international research on regional development has matured from the use of single elements and indicators to the application of comprehensive multi-element and multi-indicator measures. We selected 12 indicators from six dimensions for analysis in this study, including income, consumption, education, population urbanization, traffic, and indoor living facilities. We then proposed the polyhedron method to comprehensively measure levels of regional multidimensional development. We also enhanced the polygon and vector sum methods to render them more suitable for studying the status of regional multidimensional development. Finally, we measured levels of regional multidimensional development at county, city, and provincial scales across China and analyzed spatial differences using the three methods above and the weighted sum method applied widely. The results of this study reveal the presence of remarkable regional differences at the county scale across China in terms of single and multidimensional levels of regional development. Analyses show that values of the regional multidimensional development index (RMDI) are high in eastern coastal areas, intermediate in the midlands and in northern border regions, and low in the southwest and in western border regions. Districts characterized by enhanced and the highest levels of this index are distributed in eastern coastal areas, including cities in central and western regions, as well as areas characterized by the development of energy and mineral resources. The regional distribution of reduced and the lowest levels of this index is consistent with concentrations of areas that have always been impoverished. Correlation analyses of the results generated by the four methods at provincial, city, and county scales show that all are equivalent in practical application and can be used to generate satisfactory measures for regional multidimensional development. Additional correlation analyses between RMDI values calculated using the polyhedron method and per capita gross domestic product (GDP) demonstrate that the latter is not a meaningful proxy for the level of regional multidimensional development.  相似文献   
142.
Village-level multidimensional poverty measurement in China: Where and how   总被引:2,自引:2,他引:0  
Village is an important implementation unit of national poverty alleviation and development strategies of rural China, and identifying the poverty degree, poverty type and poverty contributing factors of each poverty-stricken village is the precondition and guarantee of taking targeted measures in poverty alleviation strategies of China. To respond it, we construct a village-level multidimensional poverty measuring model, and use indicator contribution degree indices and linear regression method to explore poverty factors, while adopting Least Square Error (LSE) model and spatial econometric analysis model to identify the villages’ poverty types and poverty difference. The case study shows that: (1) Spatially, there is obvious territoriality in the distribution of poverty-stricken villages, and the poverty-stricken villages are concentrated in contiguous poverty-stricken areas. The areas with the highest VPI, in a descending order, are Gansu, Yunnan, Guizhou, Guangxi, Hunan, Qinghai, Sichuan, and Xinjiang. (2) The main factors contributing to the poverty of poverty-stricken villages in rural China include road construction, terrain type, frequency of natural disasters, per capita net income, labor force ratio, and cultural quality of labor force. The main causes of poverty include underdeveloped road construction conditions, frequent natural disasters, low level of income, and labor conditions. (3) Chinese poverty-stricken villages include six main subtypes, and most poverty-stricken villages are affected by multiple poverty-forming factors, reflected by a relatively high proportion of the three-factor dominant type, four-factor coordinative type, and five-factor combinative type. (4) There exist significant poverty differences in terms of geographical location and policy support, and the governments still need to carry out targeted poverty alleviation measures according to local conditions. The research can not only draw a macro overall poverty-reduction outline of impoverished villages in China, but also depict the specific poverty characteristics of each village, helping the government departments of poverty alleviation at all levels to mobilize all kinds of anti-poverty resources.  相似文献   
143.
城市效应对登陆热带气旋妮妲降水影响的模拟   总被引:2,自引:2,他引:0       下载免费PDF全文
运用中尺度数值模式WRF耦合城市冠层模式(urban canopy model,UCM),对2016年登陆深圳的热带气旋妮妲(1604)(以下简称妮妲)进行数值模拟。高分辨率数值模拟较好地再现了妮妲登陆前后的强度、路径和累积降水。利用城市化过程当中城市冠层对热带气旋降水的敏感性试验结果表明:城市冠层会减弱对流运动和水汽的输送,导致热带气旋登陆后珠江口城市群区域累积降水量略减少。应用最新的土地利用资料进行的城市下垫面敏感性试验结果表明:由于城市下垫面粗糙度增加,造成登陆地面风的减速,强度减弱,潜热通量与2 m高度比湿相应减小;城市下垫面粗糙度增加会加强该区域垂直对流运动以及不稳定能量增加,有利于降水增强,尤其在城市化下垫面处,热带气旋登陆后6 h累积降水增加量最大可超过20 mm。总体而言,对登陆热带气旋降水而言,耦合城市冠层使城市区域热带气旋降水减少,但在数值模拟中城市冠层影响作用不显著。城市化下垫面对登陆热带气旋暴雨的增幅作用明显,在登陆热带气旋降水预报中应重视。  相似文献   
144.
The topological structure of the electric topological current of the locally gauge invariant Maxwell-Chern-Simons Model and its bifurcation is studied. The electric topological charge is quantized in term of winding number. The Hopf indices and Brouwer degree labeled the local topological structure of the electric topological current. Using Φ-mapping method and implicit function theory, the electric topological current is found generating or annihilating at the limit points and splitting or merging at the bifurcate points. The total electric charge holds invariant during the evolution. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
145.
化肥是提高作物产量的物质基础, 在过去的几十年中, 它在世界农业建设中起过巨大作用。近百年的肥料试验表明, 化学肥料具有和有机质一样的持续增产效果, 在提高作物产量、品质的同时, 还可培肥土壤。随着化肥工业的发展, 化肥的负作用会逐渐减小。  相似文献   
146.
In this paper,the data of continuous atmospheric vertical integral vapour and liquid water content during April-June of 1992-1994 obtained by a ground-based dual-channel microwave radiometer are used to analyse the statistical characteristics of atmospheric vapour and liquid water content,and the relative distribution characteristics of vapour and liquid water content in cloudy atmosphere,the correlative relation of integral liquid water content L and ground precipitation intensity I.and precipitation transform rate of precipitation system.Finally,the weather modification condition of precipitus stratiform clouds and seeding potential is analyzed and discussed.  相似文献   
147.
近40年湖南洪涝灾害的演变趋势及其成因   总被引:7,自引:1,他引:6  
段德寅  汪扩军  陆魁东 《气象》1999,25(6):42-46
利用湖南52个代表站1958 ̄1998年4 ̄9月的降水资料,确定了洪涝年,分析了近40年湖南洪涝的特征和演变趋势。在此基础上,探讨了近期洪涝灾害日益严重的原因。它们是:气候背景因素,大气环流异常,厄尔尼诺的影响,洞庭湖的水文特性和面积锐减,社会因素。  相似文献   
148.
GMS实时资料识别冰雹研究   总被引:4,自引:0,他引:4  
段旭  雷茂生  李英 《气象》1999,25(12):21-23
利用1997 ̄1998年3 ̄4月GMS-5的红外亮温和水汽亮温资料,根据云南春季冰雹和非冰雹的红外、水汽亮温值二维概率分布,建立数学判别式、结果表明,我必 非冰雹的识别率为94%,冰雹判虽准确率为30.8%。  相似文献   
149.
The observation on the outcrop in the field is one of the most direct and efficient methods to obtain the underground formation information, which provides the most direct first-hand geological data for geological science research. However, the traditional outcrop investigation, especially for the outcrop with a large slope and unreachable area, mainly relies on the inspection, measurement of the slope bottom, and photos to record outcrop information, making it difficult to accurately characterize the whole geological body. Consumer unmanned aerial vehicle (UAVs) with the advantages of good mobility, strong adaptability and low cost, can obtain outcrop images from a short distance, multiple perspectives and varying heights. In this paper, the image acquisition method and model construction accuracy without control points available for the geological outcrop with a large slope are discussed. Consumer UAVs is used to capture images through vertical route and then the geological model is set up. The results show that oblique photogrammetry technology combined with consumer UAVs can effectively build a large slope geological outcrop model with millimeter resolution. The model has the characteristics of high resolution, uniform resolution and high measurement accuracy up to millimeter, which can effectively reduce the difficulty of field investigation and the personnel safety risk, thus it accurately reproduces the outcrop situation with large slope in the field, providing a real and reliable data basis for the section interpretation, analysis and measurement of large slope outcrop.  相似文献   
150.
云南暴雨涡散场动能转换函数的动态分析   总被引:1,自引:0,他引:1  
对1996年云南主汛期(6-8月)逐日散度风动能和旋转风动能之间的转换函数C(KD,KR)特征进行深入研究,同时分析了C(KD,KR)各项Af、Az、B、C在动能转换函数中所起的作用。研究结果表明,对流层内C(KD,KR)>0,同时对流层低层的C(K,KR)>中高层的C(KD,KR)之和.极易出现暴雨过程;Af项在整个动能转换中起主要作用,71%的Af与C(KD,KR)具有相同的符号,Az项和B项在动能转换中起振荡作用,Az+B控制着29%的动能转换方向。  相似文献   
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