城市消防应急指挥地理信息服务系统开发研究     

周士刚 《测绘与空间地理信息》2014,(5):133-136

阐述了GIS(地理信息系统)的概念、特点以及GIS技术应用的范围,分析了城市消防附属设施资源与GIS技术的紧密相关特性。以城市消防部门应用需求为基础,提出了基于GIS技术的城市消防应急指挥地理信息系统结构设计、数据库设计、专题空间地理信息数据设计、功能设计等。最后结合哈尔滨市城市消防应急指挥地理信息系统开发试验,展示了部分项目开发内容。  相似文献   

基于布尔矩阵的空间关联规则提取方法研究     

陈俊明 《测绘与空间地理信息》2014,(5):123-126

空间关联规则是空间数据挖掘(SDM)中的重要内容之一。由于空间数据的复杂性,传统的空间关联规则挖掘方法主要是将空间数据库变换为非空间数据库,通过挖掘算法挖掘空间关联规则。目前,Apriori算法是关联规则挖掘中使用最为普遍的算法,但是,由于该算法在关联规则提取过程中需要多次扫描数据库,并且产生冗余的候选项集,因此,在执行大型数据库的关联规则挖掘时,具有效率低下的缺陷。本文基于Apriori算法提出了基于布尔矩阵的空间关联规则挖掘算法,并以挖掘福建省厦门市土地覆盖现状与地形特征因子的空间关联关系作为试验案例,对比Apriori算法的提取结果与提取效率,结果表明:该算法不仅减少了扫描数据库的次数,而且减少了冗余候选项集的产生,提高了空间关联规则的提取效率。  相似文献   

基于bat和vbs的Oracle属性数据和ArcSDE空间数据自动备份技术     

曹铁朋 《测绘与空间地理信息》2014,(7):74-76,79

数据库自动备份功能的实现大都是制作一个工具在Windows任务里定时执行,而工具的制作则多种多样,可以使用高级语言开发平台编写,也可以使用脚本写成批命令执行。常规的是开发一个自动备份工具,这样做有一定的开发量,且需要依赖某些部署环境。本文介绍在Windows平台下,如何仅通过dos命令和vbs脚本完成Oracle属性数据和ArcSDE空间数据的自动备份功能。  相似文献   

倾斜航空摄影斜视影像分辨率分析     

王海风  盛艳容  马杰 《测绘与空间地理信息》2014,(9):85-88

通过分析倾斜航摄仪的特点,提出一种面向倾斜影像的三维影像分辨率,介绍了3个方向分辨率概念以及推导了斜视影像分辨率的计算公式。结合当前市场上主流的倾斜航摄仪配置,分析了其影像分辨率变化的特点。本文得出的结论对航空摄影设计有重要指导意义,为影像量测精度分析打下了基础。  相似文献   

基于ArcGIS Server的医院网络地理信息服务系统     

高翔  蔡国林  徐柱 《测绘与空间地理信息》2014,(9):42-45

为解决目前医院地理信息服务系统在信息共享、空间分析等方面的不足,采用ArcGIS Server组件、C#编程语言、SQL Server数据库研发了医院网络地理信息服务系统。该系统以天地图作为基础地理数据,融合医院空间与医疗信息,并部署到互联网环境中。除具有医疗专题信息的网络浏览与查询外,系统还实现了诸多空间分析、地学统计等功能,既可为市民就医提供更全面的信息查询,又可为医疗事故的突发与应急提供技术支撑。  相似文献   

运用SI-Harris算子提取遥感图像点特征   总被引：1，自引：0，他引：1  

孟伟灿  朱述龙  曹闻  杨海鹏  刘岩 《测绘科学技术学报》2014,(4)

推导了SI-Harris算子(尺度不变Harris算子)的理论公式,并将其应用于遥感图像的点特征提取。重点对Harris算子与SI-Harris算子在不同空间分辨率遥感图像上的点特征提取进行实验比较,利用"重复率"指标对实验结果进行定量评价。实验表明:SI-Harris算子"重复率"较Harris算子有明显提升,可用于不同空间分辨率遥感图像的点特征提取,进而可服务于不同空间分辨率遥感图像的匹配。  相似文献   

Graded-Density Reservoirs for Accessing High Stress Low Temperature Material States   总被引：1，自引：0，他引：1  

Raymond F. Smith  K. Thomas Lorenz  Darwin Ho  Bruce A. Remington  Alex Hamza  John Rogers  Stephen Pollaine  Seokwoo Jeon  Yun-Suk Nam  J. Kilkenny 《Astrophysics and Space Science》2007,307(1-3):269-272

In recently developed laser-driven shockless compression experiments an ablatively driven shock in a primary target is transformed into a ramp compression wave in a secondary target via unloading followed by stagnation across an intermediate vacuum gap. Current limitations on the achievable peak longitudinal stresses are limited by the ability of shaping the temporal profile of the ramp compression pulse. We report on new techniques using graded density reservoirs for shaping the loading profile and extending these techniques to high peak pressures.  相似文献   

On the cosmic ray spectrum from type II supernovae expanding in their red giant presupernova wind     

《Astroparticle Physics》2015

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Assessment of future runoff trends under multiple climate change scenarios in the Willamette River Basin,Oregon, USA     

Il‐Won Jung  Heejun Chang 《水文研究》2011,25(2):258-277

We investigated trends in future seasonal runoff components in the Willamette River Basin (WRB) of Oregon for the twenty‐first century. Statistically downscaled climate projections by Climate Impacts Group (CIG), eight different global climate model (GCM) simulations with two different greenhouse gas (GHG) emission scenarios, (A1B and B1), were used as inputs for the US Geological Survey's Precipitation Runoff Modelling System. Ensemble mean results show negative trends in spring (March, April and May) and summer (June, July and August) runoff and positive trends in fall (September, October and November) and winter (December, January and February) runoff for 2000–2099. This is a result of temperature controls on the snowpack and declining summer and increasing winter precipitation. With temperature increases throughout the basin, snow water equivalent (SWE) is projected to decline consistently for all seasons. The decreases in the centre of timing and 7‐day low flows and increases in the top 5% flow are caused by the earlier snowmelt in spring, decreases in summer runoff and increases in fall and winter runoff, respectively. Winter runoff changes are more pronounced in higher elevations than in low elevations in winter. Seasonal runoff trends are associated with the complex interactions of climatic and topographic variables. While SWE is the most important explanatory variable for spring and winter runoff trends, precipitation has the strongest influence on fall runoff. Spatial error regression models that incorporate spatial dependence better explain the variations of runoff trends than ordinary least‐squares (OLS) multiple regression models. Our results show that long‐term trends of water balance components in the WRB could be highly affected by anthropogenic climate change, but the direction and magnitude of such changes are highly dependent on the interactions between climate change and land surface hydrology. This suggests a need for spatially explicit adaptive water resource management within the WRB under climate change. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

Spatial interpolation of snow water equivalency using surface observations and remotely sensed images of snow‐covered area     

Brian J. Harshburger  Karen S. Humes  Von P. Walden  Troy R. Blandford  Brandon C. Moore  Raymond J. Dezzani 《水文研究》2010,24(10):1285-1295

As demand for water continues to escalate in the western Unites States, so does the need for accurate monitoring of the snowpack in mountainous areas. In this study, we describe a simple methodology for generating gridded‐estimates of snow water equivalency (SWE) using both surface observations of SWE and remotely sensed estimates of snow‐covered area (SCA). Multiple regression was used to quantify the relationship between physiographic variables (elevation, slope, aspect, clear‐sky solar radiation, etc.) and SWE as measured at a number of sites in a mountainous basin in south‐central Idaho (Big Wood River Basin). The elevation of the snowline, obtained from the SCA estimates, was used to constrain the predicted SWE values. The results from the analysis are encouraging and compare well to those found in previous studies, which often utilized more sophisticated spatial interpolation techniques. Cross‐validation results indicate that the spatial interpolation method produces accurate SWE estimates [mean R² = 0·82, mean mean absolute error (MAE) = 4·34 cm, mean root mean squared error (RMSE) = 5·29 cm]. The basin examined in this study is typical of many mid‐elevation mountainous basins throughout the western United States, in terms of the distribution of topographic variables, as well as the number and characteristics of sites at which the necessary ground data are available. Thus, there is high potential for this methodology to be successfully applied to other mountainous basins. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献