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161.
软件以小方块在地图上标注全国195个地区的实际位置,按ISO 9223标准对各地区的年润湿时间进行分级,并以不同的颜色对应不同的等级。使用软件可查询1991年至2000年全国195个地区大气润湿时间的分布状况;不同临界相对湿度的润湿时间;各年润湿时间的变化规律情况,包括10年润湿时间的平均值和标准差;年润湿时间在各温度段所占的比例。  相似文献   
162.
移动通讯发射基站功率密度对辐射环境影响分析   总被引:1,自引:0,他引:1  
采用理论预测和实际测量的方法,对辽宁省移动通信有限公司的发射基站的电磁辐射对周边环境的影响做出预测并实际测量了场强,测算出污染半径及范围,为环境管理提供了技术支持。  相似文献   
163.
This paper presents an overview and process for developing an Internet Map Server (IMS) application for a local volunteer watershed group using an Internal Internet Map Server (IIMS) strategy. The paper illustrates that modern GIS architectures utilizing an internal Internet map server coupled with a spatial SQL command language allow for rapid development of IMS applications. The implication of this approach means that powerful IMS applications can be rapidly and affordably developed for volunteer organizations that lack significant funds or a full time information technology staff.  相似文献   
164.
为直观展现国际范围内应急管理的研究态势,以2001—2011年间SSCI数据库中相关文献和数据为基础,运用Cite SpaceⅡ软件绘制应急管理研究领域的知识图谱。通过知识图谱可视化分析,展示国际应急管理领域主要研究力量的分布,应急管理研究的起源与知识基础,其学科领域和前沿的基本态势。研究结果表明,应急管理已成为研究热点,主要力量集中在欧美发达国家。相关研究起源于医疗卫生领域,目前研究内容延伸到自然灾害、事故灾难、公共卫生事件与社会安全事件等诸多领域。研究前沿问题集中在"恐怖主义"、"实时生产监控"、"突发事件"、"应急响应"、"应急护理"等方面。  相似文献   
165.
The main aim of this study was to develop a procedure that minimizes the wasting of space for the siting of hazardous waste landfills as part of a solid waste management system. We wanted to tackle the shortage of land for waste disposal that is a serious and growing problem in most large urban regions. The procedure combines a multi-criteria decision analysis (MCDA) approach with a geographical information system (GIS). The GIS was utilised to obtain an initial screening in order to eliminate unsuitable areas, whereas the MCDA was developed to select the most suitable sites. The novelty of the proposed siting procedure is the introduction of a new screening phase before the macro-siting step aimed at producing a “land use map of potentially suitable areas” for the siting of solid waste facilities which simultaneously takes into consideration all plant types. The issue of obtaining sites evaluations of a specific facility was coupled with the issue of not wasting land appropriate to facilitate other types of waste management options. In the developed case study, the use of an innovative criteria weighting tool (the “Priority Scale”) in combination with the Analytic Hierarchy Process was useful to easier define the priorities of the evaluation criteria in comparison with other classic methods such as the Paired Comparison Technique in combination with the Simple Additive Weighting method.  相似文献   
166.
The role of behavioral ecology in improving wildlife conservation and management has been the subject of much recent debate. We sought to answer 2 foundational questions about the current use of behavioral knowledge in conservation: To what extent is behavioral knowledge used in wildlife conservation and management, and how does the use of animal behavior differ among conservation fields in both frequency and types of use? We searched the literature for intersections between key fields of animal behavior and conservation and created a systematic heat map (i.e., graphical representation of data where values are represented as colors) to visualize relative efforts. Some behaviors, such as dispersal and foraging, were commonly considered (mean [SE] of 1147.38 [353.11] and 439.44 [108.85] papers per cell, respectively). In contrast, other behaviors, such as learning, social, and antipredatory behaviors were rarely considered (mean [SE] of 33.88 [7.62], 44.81 [10.65], and 22.69 [6.37] papers per cell, respectively). In many cases, awareness of the importance of behavior did not translate into applicable management tools. Our results challenge previous suggestions that there is little association between the fields of behavioral ecology and conservation and reveals tremendous variation in the use of different behaviors in conservation. We recommend that researchers focus on examining underutilized intersections of behavior and conservation themes for which preliminary work shows a potential for improving conservation and management, translating behavioral theory into applicable and testable predictions, and creating systematic reviews to summarize the behavioral evidence within the behavior‐conservation intersections for which many studies exist.  相似文献   
167.
In the long distance pipeline remote monitoring system, small leak detection becomes an important issue. Weak singularities in small leak signals are usually difficult to detect precisely under complicated noise background, which may cause false alarm or miss alarm. The advantage of applying the harmonic wavelet method is explored in this paper. Pipeline small leak sensitive characteristics are recognized and the negative pressure wave inflexions are extracted by harmonic wavelet analysis, expressed in terms of harmonic wavelet time-frequency mesh map, time-frequency contour map, and time-frequency profile plot. This paper also presents a comparative study of both Daubechies wavelet and harmonic wavelet analysis when applied to pipeline small leak detection under complicated background noises. Results of simulating test and field experiment show that it is possible to distinguish weak non-stationarities from complicated noises by harmonic wavelet analysis in pipeline small leak detection system. The comparison clearly illustrates that harmonic wavelet based pipeline small leakage detection method is significantly more accurate than other wavelets analysis such as Daubechies wavelet. This work provides a reliable and safe guarantee for oil and gas long distance transportation, reducing petroleum product losses and protecting surrounding environment.  相似文献   
168.
Lack of sanitation affects the lives of billions of people worldwide. It is now generally agreed that sustainable solutions to this complex problem require social and cultural factors to be addressed in addition to the habitual economic and technical aspects. Increasingly, sector professionals view the fragmented approaches to sanitation as a limiting factor. This refers to the fragmentation of the knowledge on the subject among often hermetic disciplines and to the distribution of political mandates on sanitation across many institutions, which independently tackle specific aspects of the issue. Holistic approaches have often been suggested as a solution. This paper presents the development of such a holistic approach, designed to assess sanitation development in rural and peri-urban settings. Tested in three Mexican communities, it relies on qualitative research tools to identify critical influences to sanitation development. This article presents generic results about micro and macro-factors affecting sanitation development in Mexican villages, and reflexively examines the research process as well as the strengths and limitations of the approach. The conceptual map developed for each case study successfully highlights the interconnectedness of all factors affecting sanitation development. Despite some weaknesses, these maps constitute a practical assessment tool for interdisciplinary teams deployed in integrated water and sanitation development programs and a valuable didactic tool for training activities.  相似文献   
169.
为了研究太原汾河景区的水质状况并为其水质保护和水华暴发预警及防治提供依据,2012年6月至10月,对该区域8个采样点的浮游藻类细胞密度、氨氮、总氮和总磷及它们之间的关系进行了调查分析。结果表明,多数样点总氮超标,总磷相对稳定,均不超标,氮磷比变化较明显,多数采样点以7月份的细胞密度较高,下游端较上游端浮游藻类生长旺盛,污染情况也较为严重。多数采样点浮游藻类细胞密度与总氮和氮磷比呈负相关,与总磷呈正相关。  相似文献   
170.
近30 a基本农田领域研究态势的可视化分析   总被引:4,自引:0,他引:4  
论文通过收集"基本农田"为关键词的537篇检索文献,建立关键词共现关系聚类图谱与时区图谱,以Citespace可视化分析法分析近30 a(1986—2015年)中国基本农田领域研究的发展态势。研究结果表明:1)基本农田领域的研究聚类集中在基本农田保护、评价、划定以及建设等4个领域,研究内容与方法侧重点不同;2)基本农田研究内涵及内容体系丰富,具有明显的时代性特征,并且具有明显的地域差异性和时间变异性;3)基本农田研究还存在一定的共性问题,一是基本农田划定与评价指标体系过于笼统,评价体系缺乏协调性,二是缺少各级别的基金资助与支持。研究建议:基本农田评价与划定标准体系要考虑区域特征与需求;基本农田研究要适应土地利用规划及土地整治等国家战略要求;同时,基本农田研究应是一项科学问题,要发展成为国家自然基金等资助的重要检索关键词与申报领域。  相似文献   
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