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241.
电子政务建设是我国国民经济和社会发展信息化建设的重要组成部分,也是贯彻落实十六大精神、深化行政管理体制改革的重要内容。本文介绍了电子政务的概念、电子政务的应用领域,并结合环境管理和政务信息化的任务,讨论了环境电子政务建设中相关的几个问题。  相似文献   
242.
This paper considers the contribution of computing to the implementation of a policy of partnership between public environmental agencies and local voluntary groups. The present policy commitment to partnerships of this kind is reviewed. Particular information needs arise when public agencies seek to give co‐ordinated support to the environmental action undertaken by local groups. These stem from the disaggregated nature of the structure and functions of the voluntary sector. Computer‐based information systems are identified as a bridge between the regional organisation of public agencies and the local activities of voluntary groups. A computer system devised to aid the forward planning of public support for voluntary action is described. It is considered that this technique has value as part of a wider strategy of interaction between the public and voluntary sectors.  相似文献   
243.
Environmental programs have been commonly driven by a preoccupation with the collection of data in the mistaken belief thatdata is synonymous withinformation. The distinction between data (that is, the quantified and qualitative attributes of a particular environment) and information (specifically, data processed so as to focus upon a particular environmental problem) will become far more important to environmental managers. They will increasingly manage their information through use of what has become known as information resource management (IRM) and the attendant use of critical success factors methodology. Environmental managers will thereby move away from concerns about data and specific EDP hardware and applications toward managing information as a valuable agency resource. In applying IRM, they will find it helpful to include a number of planning elements and to resolve early a number of issues critical to its successful use.  相似文献   
244.
Gall M 《Disasters》2004,28(1):82-97
This paper, through spatial-analysis techniques, examines the accessibility of emergency shelters for vulnerable populations, and outlines the benefits of an extended and permanently established shelter network in central Mozambique. The raster-based modelling approach considers data on land cover, locations of accommodation centres in 2000, settlements and infrastructure. The shelter analysis is a two-step process determining access for vulnerable communities first, followed by a suitability analysis for additional emergency shelter sites. The results indicate the need for both retrofitting existing infrastructure (schools, health posts) to function as shelters during an emergency, and constructing new facilities - at best multi-purpose facilities that can serve as social infrastructure and shelter. Besides assessing the current situation in terms of availability and accessibility of emergency shelters, this paper provides an example of evaluating the effectiveness of humanitarian assistance without conventional mechanisms like food tonnage and number of beneficiaries.  相似文献   
245.
Inappropriate decisions are often regarded as causes of major accidents in the process industries. To improve the quality of decisions, it is important to make the right information available at the right time. The objective of this work is to investigate what types of risk information is needed for risk-related decisions in various decision-making processes. A framework is proposed to facilitate future research for easing information deficiency. In this paper, risk information is examined through common decision-making processes, and is identified serving to 1) detect and characterize risk-related decision problems, 2) indicate the severity and urgency of decisions, 3) state requirements and constraints of workable solutions, 4) represent attributes for comparing and evaluating solutions, and 5) act as rules to maintain safety or control risk. These usages of risk information in different decision problems imply the large diversity in information needs for decision-making. An adaptive information support is thus suggested to provide targeted risk information to specific decision-makers for effective and efficient decision-making in accident prevention in the process industries.  相似文献   
246.
• ORP value from −278.71 to −379.80 mV showed indiscernible effects on methane yield. • Fe(II) and Fe(III) promoted more degradation of proteins and amino acids than Fe0. • The highest enrichment of Geobacter was noted in samples added with Fe0. • Cysteine was accumulated during iron enhanced anaerobic sludge digestion. • Both iron content and valence were important for methane production. This study compared effects of three different valent iron (Fe0, Fe(II) and Fe(III)) on enhanced anaerobic sludge digestion, focusing on the changes of oxidation reduction potential (ORP), dissolved organic nitrogen (DON), and microbial community. Under the same iron dose in range of 0−160 mg/L after an incubation period of 30 days (d), the maximum methane production rate of sludge samples dosed with respective Fe0, Fe(II) and Fe(III) at the same concentration showed indiscernible differences at each iron dose, regardless of the different iron valence. Moreover, their behavior in changes of ORP, DON and microbial community was different: (1) the addition of Fe0 made the ORP of sludge more negative, and the addition of Fe(II) and Fe(III) made the ORP of sludge less negative. However, whether being more or less negative, the changes of ORP may show unobservable effects on methane yield when it ranged from −278.71 to −379.80 mV; (2) the degradation of dissolved organic nitrogen, particularly proteins, was less efficient in sludge samples dosed with Fe0 compared with those dosed with Fe(II) and Fe(III) after an incubation period of 30 d. At the same dose of 160 mg/L iron, more cysteine was noted in sludge samples dosed with Fe(II) (30.74 mg/L) and Fe(III) (27.92 mg/L) compared with that dosed with Fe0 (21.75 mg/L); (3) Fe0 particularly promoted the enrichment of Geobacter, and it was 6 times higher than those in sludge samples dosed with Fe(II) and Fe(III) at the same dose of 160 mg/L iron.  相似文献   
247.
概要地介绍了中文环境科技核心期刊、美国《工程索引》(EI)和《科学引文索引》(SCI)收录中国科研论文的情况,以及两份知名英文环境期刊的论文评审标准。EI和SCI收录其来源期刊中英文摘要符合要求的论文。一篇好英文摘要有助于论文被国际环境期刊录用和增加论文的影响力。基于目前EI及SCI的来源期刊中缺少中文专业期刊,国内的环境科研人员可以先将其重要研发成果陆续在中文环境核心期刊上发表,形成系列文章,然后再融合这些文章,投寄英文国际环境期刊。这个策略可及时将研发成果公开发表,提高论文被国际期刊录用的几率,并增加中文环境核心期刊的知名度和声望。  相似文献   
248.
SUMMARY

The causes for environmental breaches producing losses to the forest resources in the biosphere reserve Mariposa Monarca in Mexico have been investigated, mainly using methods of spatial analysis. It was demonstrated that the availability of forest resources themselves does not affect the frequency of breaches but does have consequences on the amount of resource loss per breach. Furthermore, a strong dependency on the traffic ways was demonstrated. The larger the distance to the traffic ways, the lower is the frequency of breaches. This behaviour could be described mathematically and led to the result that 38% of the breaches can be considered as caused by traffic ways. A weak dependency on the number of inhabitants could be found but no dependency on socioeconomic parameters. Taking into account the results of this analysis, a simple resource management model was developed, using a differential equation. It estimates the future development of natural resources. The model is implemented in a Geographic Information System. Sample calculations underline the importance of the supervising actions and show the possibilities of the model with respect to the measures that have to be taken to preserve natural resources in a supervised national park.  相似文献   
249.
光电芬顿氧化法深度处理垃圾渗滤液研究   总被引:6,自引:1,他引:5  
采用光电芬顿氧化法对北京市某垃圾填埋场已经生化处理后的垃圾渗滤液进行深度处理,分别考察了电流强度和铁的不同价态等因素对渗滤液总有机碳(TOC)、化学需氧量(COD)以及色度去除效果的影响,并对阳极氧化、电芬顿和光电芬顿不同反应过程进行了对比。通过分析渗滤液UV-Vis光谱(200~500 nm)变化和渗滤液中有机污染物的分子量变化,发现光电芬顿反应可以明显改善渗滤液生化性。深入研究了反应过程中铁价态的变化规律。试验结果发现,以高比表面积的活性炭纤维(ACF)为阴极的光电芬顿反应可以有效降解垃圾渗滤液,在pH为3,Fe2+ 浓度为1 mmol/L,电流为0.5 A,O2通入量为250 mL/min条件下降解360 min,垃圾渗滤液TOC和COD去除率分别达到78.9%和62.8%,色度完全去除。  相似文献   
250.
危险化学品运输管理及事故应急系统探讨   总被引:1,自引:7,他引:1  
通过全球定位系统(GPS)、地理信息系统(GIS)、专家系统(ES)、自动监测等技术的集成,充分发挥各自技术的优势,建立危险化学品运输及事故应急系统。该系统由基于GPS技术的“运输车辆管理”、基于自动监测技术的“事故自动报警”、基于扩散数学模型和GIS技术的“泄漏模拟分析”、基于专家系统的“事故应急救援”以及基于Web技术“信息发布及数据维护”等5个子系统组成,通过集成各子系统实现危险化学品运输管理的自动化、智能化,在事故发生的第一时间自动报警,避免因人为因素而贻误救援时间,同时通过现场信息数据分析做出最有效的救援安排。  相似文献   
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