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1.
目的:研究黄芩在河北省燕山及太行山山脉生态适宜性区划。方法:通过第四次全国中药资源普查等方式获取黄芩分布位点信息,利用地理信息系统技术和最大信息熵模型分析其分布区的主导生态因子、数值和权重,得出黄芩药材在河北省的生态适宜生长区。结果:研究表明,海拔、坡度、最暖季降水量、最湿月降水量、年均温、土壤类型、植被类型7项环境因子是影响黄芩分布的主要生态因子;黄芩在河北省的生态适宜生长区主要分布在承德、张家口、保定等地的燕山及太行山山脉区域。结论:可在太行山山脉的承德市、张家口市、保定市,燕山山脉的秦皇岛市引种栽培黄芩。  相似文献   
2.
基于GIS的卫勤指挥自动化系统设计   总被引:2,自引:0,他引:2  
地理信息系统(GIS)是在现代计算机软、硬件支持下,以地理空间数据库为基础新开发构建的一个属性管理系统。具有独特项目属性信息存贮,自动查询,智能运算分析,直观仿真图示等功能。笔者认为,这个系统经二次开发,可很好的用于卫勤指挥自动化系统的建设,大有开发价值。  相似文献   
3.
This work documents ambient lead dust deposition values (lead loading) for the boroughs of New York City in 2003-2004. Currently, no regulatory standards exist for exterior concentrations of lead in settled dust. This is in contrast to the clearance and risk assessment standards that exist for interior residential dust. The reported potential for neurobehavioral toxicity and adverse cognitive development in children due to lead exposure prompts public health concerns about undocumented lead sources. Such sources may include settled dust of outdoor origin. Dust sampling throughout the five boroughs of NYC was done from the top horizontal portion of pedestrian traffic control signals (PTCS) at selected street intersections along main thoroughfares. The data (n=214 samples) show that lead in dust varies within each borough with Brooklyn having the highest median concentration (730 μg/ft2), followed in descending order by Staten Island (452 μg/ft2), the Bronx (382 μg/ft2), Queens (198 μg/ft2) and finally, Manhattan (175 μg/ft2). When compared to the HUD/EPA indoor lead in dust standard of 40 μg/ft2, our data show that this value is exceeded in 86% of the samples taken. An effort was made to determine the source of the lead in the dust atop of the PTCS. The lead in the dust and the yellow signage paint (which contains lead) were compared using isotopic ratio analysis. Results showed that the lead-based paint chip samples from intact signage did not isotopically match the dust wipe samples taken from the same surface. We know that exterior dust containing lead contributes to interior dust lead loading. Therefore, settled leaded dust in the outdoor environment poses a risk for lead exposure to children living in urban areas, namely, areas with elevated childhood blood lead levels and background lead dust levels from a variety of unidentified sources.  相似文献   
4.
基于GIS、GPS的教学模式在卫勤培训中的应用   总被引:1,自引:0,他引:1  
鉴于GIS、GPS的功能和特点,建立基于GIS、GPS的教学训练模式既扩展其应用范围,又促进卫勤干部地形数字化理念和识图能力的提高。实践证明,教学效果好、效率高,是军事地形学教学内容和手段的更新。该训练模式使卫勤指挥干部的技能更加贴近信息化战场,适应了现代战争卫勤保障的需要。  相似文献   
5.
BackgroundReducing the retail availability of tobacco has been proposed as a component of tobacco endgame, yet it is not known whether retail availability has a direct impact on smoking behaviours. A narrative review and a meta-analysis have been undertaken to examine the density and proximity of tobacco retail outlets, but were limited in scope, exposure and outcome variables. The aim of this current study was to undertake a systematic review of the international literature on the density and proximity of tobacco retail outlets to homes, schools and communities and their association with smoking behaviours among youth.MethodsWe reviewed and critically appraised the evidence documenting the association between density or proximity of tobacco retail outlets and smoking behaviours among school-age youth (18 and under), between 1 January 1990 and 21 October 2019. We reviewed original quantitative research that examined the associations of tobacco retail outlet density and proximity with individual smoking status or population-level smoking prevalence; initiation of smoking; frequency of tobacco use; sales to minors; purchasing by minors; susceptibility to smoking among non-smokers; perceived prevalence of smoking, and quitting behaviours.FindingsThirty-five peer-reviewed papers met the inclusion criteria. This review provided evidence of a relationship between density of tobacco retail outlets and smoking behaviours, particularly for the density near youths’ home. A study using activity spaces also found a significant positive association between exposure to tobacco retail outlets and daily tobacco use. The review did not provide evidence of an association between the proximity of tobacco retail outlets to homes or schools and smoking behaviours among youth.ConclusionsThe existing evidence supports a positive association between tobacco retail outlet density and smoking behaviours among youth, particularly for the density near youths’ home. This review provides evidence for the development and implementation of policies to reduce the density of tobacco retail outlets to reduce smoking prevalence among youth.  相似文献   
6.
Fire departments have right-of-entry to most commercial industrial sites and preemptively map them to identify the onsite resources and hazards they need to promptly and safely respond to an emergency event. This is not the case for private farms. Emergency responders are blind to resources and hazards prior to arrival and must spend critical minutes locating them during an emergency response at a farm location. The original 2013 Farm Mapping to Assist, Protect and Prepare Emergency Responders (Farm MAPPER) project was undertaken to develop a method to give emergency responders an up-to-date view of on-farm hazard information to safely and efficiently conduct emergency response activities on private agricultural operations. In 2017, an augmented reality version of Farm MAPPER was developed to combine the technological advantages of geographic information system-based data points with a heads-up display and graphical overlay of superimposed hazard imagery and informative icons. The development and testing of this iOS- and Android-ready prototype uncovered lessons learned applicable to other mobile-based apps targeting farmers, ranchers, and rural populations faced with limited or inconsistent mobile internet connectivity.  相似文献   
7.
Assessing access to healthcare for an entire healthcare system involves accounting for demand, supply, and geographic variation. In order to capture the interaction between healthcare services and populations, various measures of healthcare access have been utilized, including the popular two-step floating catchment area (2SFCA) method. However, despite the many advantages of 2SFCA, the problems, such as inappropriate assumption of healthcare demand and failure to capture cascading effects across the system have not been satisfactorily addressed. In this paper, a statistical model for evaluating flows of individuals was added to the 2SFCA method (hereafter we refer to it as F2SFCA) in order to overcome limitations associated with its current restriction. The proposed F2SFCA model can incorporate both spatial and nonspatial dimensions and thus synthesizes them into one framework. Moreover, the proposed F2SFCA model can be easily adapted to measure access for different types of individuals, over different service provider types, or with capacity constraints in a healthcare system. We implemented the proposed model in a case study assessing access to healthcare for the elderly in Taipei City, Taiwan, and compared the weaknesses and strengths to the 2SFCA method and its variations.  相似文献   
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9.
ObjectiveTo better determine the relationship between spatial access to colonoscopy and colorectal cancer (CRC) outcomes, our objective was to examine the agreement of the classic, enhanced, and variable two‐step floating catchment area (2SFCA) methods in evaluating spatial access to colonoscopy and to compare the predictive validity of each method related to late‐stage CRC. 2SFCA methods simultaneously consider supply/demand of services and impedance (ie, travel time).Data SourcesColonoscopy provider locations were obtained from the South Carolina Ambulatory Surgery Database. ZIP code tabulation area (ZCTA) level population estimates and area‐level poverty level were obtained from the American Community Survey. Rurality was determined by the United States Department of Agriculture''s Rural‐Urban Commuting Area codes. Individual‐level CRC data were obtained from the South Carolina Central Cancer Registry.Study DesignUsing the classic, enhanced, and variable 2SFCA methods, we calculated ZCTA‐level spatial access to colonoscopy. We assessed agreement between the three methods by calculating Spearman''s rank coefficients and weighted Kappas (Κ). Global and Local Moran''s I were used to assess spatial clustering of accessibility scores across 2SFCA methods. We performed multilevel logistic regression analyses to examine the association between spatial accessibility to colonoscopy, area‐ and individual‐level factors, and late‐stage CRC.Principal FindingsWe found strong agreement (Weighted Κ = 0.82; 95% CI = 0.79‐0.86) and identified similar clustering patterns with the classic and enhanced 2SFCA methods. There was negligible agreement among the classic/enhanced 2SFCA and the variable 2SFCA. Across all 2SFCA methods, regression models showed that spatial access to colonoscopy, rurality, and poverty level were not associated with greater odds of late‐stage CRC, though Black race was associated with late‐stage CRC across all models.ConclusionsNone of the 2SFCA methods showed an association with late‐stage CRC. Future studies should explore which elements (spatial or nonspatial) of access to care have the greatest impact on CRC outcomes.  相似文献   
10.
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