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范晓易  王夫运 《大地测量与地球动力学》2014,34(2):84-89

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协商民主理论对我国民主政治建设的启示     

郭万敏 《广东海洋大学学报》2014,(2):58-62

兴起于西方的协商民主对选举民主的功能性互补,使其在我国的民主政治建设实践中形成了中国特色社会主义协商民主,党的十八大报告中又明确"社会主义协商民主是我国人民民主的重要形式",提出要"健全社会主义协商民主制度",而西方协商民主理论对如何在我国民主政治建设中健全社会主义协商民主制度有着重要的启示。  相似文献   

小波变换用于建筑物变形监测精度的确定与评价     

朱辉 《北京测绘》2014,(6):32-35

重点分析工作中某厂房建筑物变形监测的精度确定问题,对观测环境条件较差的监测部位已有观测资料,首先实施小波变换来估计实际监测精度,然后与其相应的理论精度相比较,并结合实际监测条件评价其观测质量,从而为后续的变形监测工作提供参考。  相似文献   

The Acre Basin basement (NW Brazil) and the transition from the intracratonic to retroarc foreland basin system     

Rick Souza de Oliveira  Roberta Mary Vidotti 《Basin Research》2023,35(1):86-119

The understanding of the crustal transition between orogenic zones and cratonic portions in distal regions of foreland basins has received increasing attention, but the analysis is often hampered by the sedimentary cover. Despite the peculiar location of the Acre Basin, specifically between the Amazonian Craton and the sub-Andean zone, local basement studies are still scarce due to lacking seismic data and exploratory wells. Therefore, this work aims to map basement depths, estimate crustal compositions and identify the main depocenters, structures and limits of Acre Basin using an integrated analysis to understand better the region lithospheric evolution, its relationship with the Amazonian Craton and its positioning within the Andean orogeny. For that, we used well, 2D seismic reflection, airborne and ground gravity and magnetic data as well as the EMG2008. Tilt Depth estimates indicate basement depths between 500 and 7800 m and larger sedimentary thicknesses in the northern portion. Additionally, we modelled groups of potential sources between 0.1 and 22 km and Moho depths between 26 and 37 km. Compositionally, the upper crust consists dominantly of meta-sedimentary and low-grade metamorphic rocks and granites, indicating that the sub-Andean and Acre Basins share a similar basement. Thus, there are indications that the basement of the Acre Basin is essentially formed by the Sunsás province in the Amazonian Craton. However, local differences in basement depth, magnetic susceptibility and exploratory potential led to the subdivision into Divisor and Xapuri sub-basins, north and south of the Fitzcarrald Arch, respectively. Finally, it was possible to establish the limits of the Andean orogeny influence in the Acre Basin and delimit the area of the Western Amazon Foredeep installed during the Neogene.  相似文献   

Implications of Weighting Metrics for Line Generalization with Visvalingam's Algorithm   总被引：1，自引：0，他引：1  

M. Visvalingam  J. C. Whelan 《The Cartographic journal》2013,50(3):253-267

Visvalingam's algorithm was designed for caricatural line generalization. A distinction must be made between the algorithm and its operational definition, which includes the metric used to drive it. When the algorithm was first introduced, it was demonstrated using the concept of the effective area of triangles. It was noted that alternative metrics could be used and that the metrics could be weighted, for example to take account of shape.

Ordnance Survey (Great Britain) and others are using Visvalingam's algorithm for generalizing coastlines and other natural features, with complex parameter-driven functions to weight the original metric. This paper shows how free software and data were used to scrutinize the implications of one of Matthew Bloch's simple and transparent weighting functions. The results look promising, when compared with manually produced mid and small-scale maps; and encourage further research focussed on weighting functions and related topics, such as self-intersection of lines and model-based generalization. The paper discusses why weights were used in some projects. It comments on their range of applicability and reiterates the original guidance provided for the use of weights. It also demonstrates how weights can undermine the algorithm's capacity to draw caricatures with very few points. The paper provides sufficient background and links to the authors’ test data and to open source software for the benefit of others wishing to undertake research in line generalization using Visvalingam's algorithm.  相似文献   

Evaluation of drainage networks developed in hard rock terrain     

M. Sameena  J. Krishnamurthy  V. Jayaraman  G. Ranganna 《国际地球制图》2013,28(5):397-420

An attempt was made to study the influence of various factors such as geology, landforms, slope, soil, landuse/cover on the development of the drainage network. To compare and evaluate drainage networks developed in various geologic terrains, differing in rock type and structure, three sub-basins of the Bhadra river basin, located in Chikmagalur district, Karnataka, India were selected for the study. Quantitative morphometric analysis was carried out for both linear aspects and areal aspects for all three sub-basins. The applicability of Horton's laws was also studied. Each of the quantitative parameters was interrelated with thematic details derived from remote sensing data. The results of the study indicate that the drainage characteristics are entirely different for all three sub-basins. The study has also established the applicability of Horton's laws pertaining to quantitative morphometry of the sub-basins.  相似文献   

重庆市国土房管信息安全体系规划和实施     

王彦集  黄辉  靳莉君 《国土资源信息化》2013,(4):24-28

随着我国政府及各行业信息化进程的不断推进,信息系统安全问题已经被提升到关系国家安全的战略性高度。本文结合信息系统安全等级保护和信息安全保障体系建设等方面的工作,从信息安全建设目标、原则和体系架构三个方面,阐述了重庆市国土房管信息安全体系总体规划,并从物理安全、网络安全、主机安全、数据安全和安全制度五个方面,介绍了信息安全体系建设的主要实施内容。  相似文献   

资源三号卫星数据矿山地质环境调查研究     

刘丹丹  刘江  余凡 《测绘与空间地理信息》2013,(8):12-14

采矿引起的一系列矿山环境问题不仅威胁到人们生命财产安全,而且严重影响和制约着经济的发展,也引发了一系列社会问题和矛盾。本文运用资源三号卫星遥感数据,以黑龙江省鹤岗市为例,解译鹤岗市矿山地质环境,并对遥感图像解译成果进行综合分析研究。  相似文献   

Environmental Health Injustice: Exposure to Air Toxics and Children's Respiratory Hospital Admissions in El Paso,Texas     

Sara E. Grineski  Timothy W. Collins  Jayajit Chakraborty  Yolanda J. McDonald 《The Professional geographer》2013,65(1):31-46

Although much environmental justice research tacitly assumes that unequal environmental exposures produce geographic disparities in adverse health outcomes, very few empirical environmental justice studies have tested that assumption. This article does so by using estimates of exposure to air toxics disaggregated by emission source (point and mobile) to predict children's hospitalization rates for both asthma and respiratory infections in El Paso, Texas. Air toxics emissions from most source categories were found to be significant predictors of children's respiratory infection hospitalization rates, but not asthma hospitalization rates, at the census tract level. Findings suggest that sociospatial disparities in respiratory infection rates might be linked to environmental inequalities.  相似文献   

Soil seed bank longevity of the exotic annual grass Bromus rubens in the Mojave Desert,USA     

《Journal of Arid Environments》2013

Although arid environments are often considered among the least invaded terrestrial biomes, the impacts of exotic plant species can be severe and long lasting. Bromus rubens (red brome) is an exotic annual grass species in the Mojave Desert known to outcompete native plant species, alter habitat, and promote accumulation of fuel that contributes to increasing fire frequency and severity. We assessed longevity of the exotic B. rubens seeds in the soil by burying seeds at four depths (0, 2, 5, and 10 cm) and recovering seeds 6, 12, 18, and 24 months after burial. Seed viability was reduced with greater burial depth and greater time since burial. A relatively small proportion of seeds retained viability for two years, suggesting that while the B. rubens seed bank can be large, it is relatively short-lived. Although B. rubens apparently relies more on the annual production, dispersal, and germination of seeds than on a long-lived seed bank for its annual recruitment, the numerous seeds produced by individual plants indicate that even a small proportion of seeds remaining viable for more than a year can aid recruitment from the seed bank and is an important factor in understanding population dynamics.  相似文献