B/S模式下地质图管理系统的设计与实现     

郝明  邓昌荣  张建龙  梁虹 《地理空间信息》2011,(4):28-30,33

截止2008年底,青藏高原1：250000区域地质调查已完成100多幅地质图的建库工作,在此基础上,建立了基于WebGIS的管理系统。该系统基于国产优秀的MapGIS 7-IMS平台进行二次开发,采用B/S结构,与以往的地质软件的C/S模式相比,系统采用了B/S结构,使得系统的维护和更新方便、开发更简单并且共享性强、总...  相似文献   

Probability of serviceability failure in a braced excavation in a spatially random field: Fuzzy finite element approach   总被引：2，自引：0，他引：2  

Zhe Luo  Sez Atamturktur  C. Hsein Juang  Hongwei Huang  Ping-Sien Lin 《Computers and Geotechnics》2011

A simplified framework is proposed for evaluating the probability of “serviceability failure” in a braced excavation in a spatially random field. Here, the “serviceability failure” is said to occur when the excavation-induced wall or ground movement exceeds specified limiting values. Knowledge of this probability can aid in engineering decision-making to prevent damage to adjacent infrastructures. The proposed framework consists of five elements: (1) finite element method (FEM) for analyzing wall and ground responses in a braced excavation, (2) fuzzy set modeling of parameter uncertainty, (3) spatial averaging technique for handling spatial variability, (4) vertex method for processing fuzzy input through FEM model, and (5) interpretation of fuzzy output. The proposed framework is demonstrated through a well-documented case history. The results show the proposed framework is simple and effective for assessing the probability of serviceability failure in a braced excavation in a spatially random field. To focus on the proposed fuzzy FEM approach, the scope of this paper is limited to one-dimensional modeling of spatial variability with an assumed exponential autocorrelation function.  相似文献   

Probabilistic infinite slope analysis   总被引：1，自引：0，他引：1  

D.V. Griffiths  Jinsong Huang  Gordon A. Fenton 《Computers and Geotechnics》2011

Research activity in the mechanics of landslides has led to renewed interest in the infinite slope equations, and the need for a more general framework for giving insight into the probability of failure of long slopes involving non-homogeneous vertical soil profiles and variable groundwater conditions. This paper describes a methodology in which parameters such as the soil strength, slope geometry and pore pressures, are generated using random field theory. Within the limitations of the infinite slope assumptions, the paper clearly demonstrates the important “seeking out” effect of failure mechanisms in spatially random materials, and how “first order” methods that may not properly account for spatial variability can lead to unconservative estimates of the probability of slope failure.  相似文献   

Spatial distribution and source diagnosis of polycyclic aromatic hydrocarbons in soils from Chengdu Economic Region,Sichuan Province,western China     

Xinli Xing  Shihua Qi  Jiaquan Zhang  Chenxi Wu  Yuan Zhang  Dan Yang  Joshua Owago Odhiambo 《Journal of Geochemical Exploration》2011

Surface soils from the Chengdu Economic Region (CER) were analyzed for sixteen United States Environment Protection Agency priority polycyclic aromatic hydrocarbons (PAHs) to study the spatial distribution and to identify the sources of PAHs. Relatively high concentrations (more than 1500 ngg^− 1) of high molecular weight PAHs were found in Chengdu Plain, in the middle of CER, while high concentrations (more than 500 ng g^− 1) of low molecular weight PAHs were detected in the surrounding mountains. The concentrations of ∑₁₆-PAHs in topsoil samples from CER (12.52–75,431.47 ngg^− 1, average value was 3233.92 ngg^− 1) were higher than that from the southern China (21.91–3077 ngg^− 1, average value was less than 500 ngg^− 1), and they were comparable to concentrations in soils from the northern China (366–254,080 ngg^− 1, mean value was more than 3000 ngg^− 1). The concentrations from CER were also much higher than the concentrations of some world clean regions such as Antarctic (34.9–171 ngg^− 1), European high mountains (9–11,000 ngg^− 1, mean value was 158 ngg^− 1) and some Europe residential (736 ngg^− 1) and arable soils (60–145 ngg^− 1, mean value was 66 ngg^− 1). The ratio of tracer compounds (BaA/(BaA + Chr), Flo/(Flo + Pyr), and IcdP/(IcdP + BghiP)) indicated that the high concentrations of PAHs in soils were mainly derived from fossil fuels combustion in mountain region and from the incomplete combustion of petroleum in developed plain area (such as Chengdu and Deyang). From the above distribution characteristics and ratios of tracer compounds, we inferred the reasons for the distribution pattern of PAHs in CER were the domestic heating, emissions, and the physicochemical properties of PAHs.  相似文献   

Spatial association between regionalizations using the information-theoretical V-measure     

J. Nowosad 《International journal of geographical information science》2018,32(12):2386-2401

  相似文献   

EU marine strategy framework directive (MSFD) and marine spatial planning (MSP): Which is the more dominant and practicable contributor to maritime policy in the UK?     

《Marine Policy》2014

This paper is a comparative analysis of the contribution to UK marine governance of two recent EU initiatives: the Marine Strategy Framework Directive (MSFD) and Marine Spatial Planning (MSP). MSFD imposed a duty on Member States to achieve Good Environmental Status (GES) in four regional seas, while MSP required Member States to replace their fragmented, sector-based system of maritime decision making with an integrated approach. This paper explains MSFD and MSP, examines their relationship, and compares their practicability, concluding that MSP is both the more dominant and the more practicable instrument, reflecting the UK's preference for sustainable development over conservationism in marine policy. A recent proposal by the European Commission to make MSP and integrated coastal management a Directive reinforces the UK position.  相似文献   

Issues and challenges in spatio-temporal application of an ecosystem services framework to UK seas     

《Marine Policy》2014

The concepts of ecosystem services and human welfare provide strong integrative frameworks that can be used to inform marine policy and management decisions that support sustainable development. A theoretical framework has been developed and applied to create a model for UK seas to measure changes in final ecosystem services, in terms of human welfare. The model that has been developed is explicitly spatial and temporal to facilitate its use in supporting marine planning decisions. The development and application of this framework to UK seas necessarily requires many assumptions to be made. The paper describes the development and population of the framework and discusses the practical limitations and challenges in seeking to develop and apply such models. Significant differences in long-term values of different services were identified under the different scenarios. All scenarios highlight the projected decline in oil and gas revenues which provide particular intense values at sites of extraction. These values are partially replaced by revenues from offshore renewables in some of the scenarios. Values associated with carbon sequestration, maritime transport, tourism and pollution assimilation are also very significant but more spatially diffuse. The study has demonstrated that it is possible to develop spatio-temporal models to evaluate changes in final ecosystem service benefits using existing data, although the approach necessarily requires many assumptions to be made.  相似文献   

1961-2010 年东北地区降水事件时空均匀性研究   总被引：3，自引：0，他引：3  

李邦东  ;赵中军  ;舒黎忠  ;王式功  ;尚可政 《气象与环境学报》2014,30(3):52-58

利用1961-2010年东北三省和内蒙古四盟90个气象站逐日降水资料,分析了中国东北地区降水事件的气候特征及时空分布均匀性变化。结果表明：近50 a来,东北地区年降水量略有减少,但冬、春季降水量显著增加;考虑降水日数,冬、春季降水量增加主要是由于降水强度的增加,夏、秋季降水量减少主要是由于降水频次的减少。气候变暖的大背景下,虽然年降水量线性变化趋势并不明显,但是降水量年际间分布不均匀性增加,降水有向极端化发展的趋势,夏、秋季表现更为明显,各等级降水事件尤其是降雪在近20 a时间分布明显不均匀。降水量空间均匀性在1993年发生转折突变,突变后空间不均匀性增加,降水日数空间均匀性在1986年发生变率突变,突变后振荡加剧。降水事件时空不均匀性的增加一定程度上造成了东北地区旱涝事件发生可能性增加,不同地域旱涝事件同发现象加剧。  相似文献   

Effect of spatial and temporal scales on habitat suitability modeling: A case study of Ommastrephes bartramii in the northwest pacific ocean     

Caixia Gong  Xinjun Chen  Feng Gao  Siquan Tian 《中国海洋大学学报(英文版)》2014,13(6):1043-1053

Temporal and spatial scales play important roles in fishery ecology, and an inappropriate spatio-temporal scale may result in large errors in modeling fish distribution. The objective of this study is to evaluate the roles of spatio-temporal scales in habitat suitability modeling, with the western stock of winter-spring cohort of neon flying squid(Ommastrephes bartramii) in the northwest Pacific Ocean as an example. In this study, the fishery-dependent data from the Chinese Mainland Squid Jigging Technical Group and sea surface temperature(SST) from remote sensing during August to October of 2003–2008 were used. We evaluated the differences in a habitat suitability index model resulting from aggregating data with 36 different spatial scales with a combination of three latitude scales(0.5°, 1° and 2°), four longitude scales(0.5°, 1°, 2° and 4°), and three temporal scales(week, fortnight, and month). The coefficients of variation(CV) of the weekly, biweekly and monthly suitability index(SI) were compared to determine which temporal and spatial scales of SI model are more precise. This study shows that the optimal temporal and spatial scales with the lowest CV are month, and 0.5° latitude and 0.5° longitude for O. bartramii in the northwest Pacific Ocean. This suitability index model developed with an optimal scale can be cost-effective in improving forecasting fishing ground and requires no excessive sampling efforts. We suggest that the uncertainty associated with spatial and temporal scales used in data aggregations needs to be considered in habitat suitability modeling.  相似文献   

Social participation and social capital with equity and efficiency: An approach from central-place theory     

《Applied geography (Sevenoaks, England)》2014

A great deal of attention has been paid to the efficiency of the analysis of sustainable urban and regional growth. This includes social participation and social capital, which require a consideration of equity. In this paper, an approach from central-place theory for sustainable urban and regional growth is examined, taking into consideration relevant variables such as ageing, social interaction and accessibility. A lack of consideration of equity could cause several social exclusion problems, and these problems could develop into spatial consumer exclusion. Solutions for these problems would not only improve equity but also efficiency, and the outcome would addresses the necessity of an alternative spatial formation based on a wider-regional rural central-place system according to given economic, social and spatial configurations.  相似文献