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111.
112.
“江苏重点污染源污染物排放总量监测管理信息系统”软件是以全省重点污染源年排放申报登记数据和江苏省环境水系的编码成果作为系统设计的基础。该系统的功能框架设计是在征求了环境监测管理部门使用意见后逐步形成的,系统设计采用分模块平行开发方式,以微软新一代先进的开发平台,NET作为开发环境,用Access数据库管理软件存储全省总量监测数据。该系统具有对重点污染源废水,废气污染物监测的收集,汇总,分析,查询和报表打印等功能。 相似文献
113.
Sutphen S 《Disasters》1983,7(3):194-201
A case study of a flood which occurred at Lake Elsinore, California, February, 1980, focuses upon the assistance which the community received during both the flood and recovery periods. Relevant literature on disaster research is examined, including a model of disaster recovery, and the study places the events which occurred din Lake Elsinore within that recovery model. Implications for policy include the recommendation that decision-makers consider the pre-disaster growth of the community indecisions to support recovery assistance. 相似文献
114.
Kastner R 《Disasters》1983,7(1):41-43
Abstract—This paper describes in detail the separate components of an ideal expatriate refugee health worker training course. Emphasis is given to organizational aspects of such courses. 相似文献
115.
Access数据库加密系统安全性剖析及改进策略 总被引:6,自引:0,他引:6
MSAccess是国内中小型企业的MIS广泛采用的数据库系统,它开发和维护都很方便,而且数据处理功能强大,是目前应用最为广泛地中小型数据库系统。但是由于其在加密方面设计欠周密,造成用户可以通过日期字段等方式对隐藏的密钥进行还原,使之成为该种数据库系统首要安全问题。笔者对其加密系统的漏洞和各种获取Access数据库密码的方式进行分析,提出一种通用的动态密钥空间加密技术改进和保护同类问题数据库系统。该技术具有密码保护的通用性和确保加密信息安全的特殊性;必定能为目前广大的MSAccess用户现存的数据安全问题的解决提供良好的思路和实施方法。同时它也给具有类似安全漏洞的大型数据库的加密体系的设计提供一个极好的新策略。 相似文献
116.
Impact significance determination is widely recognized as a vital and critical EIA activity. But impact significance related concepts are poorly understood. And the quality of approaches for impact significance determination in EIA practice remains highly variable. This article seeks to help establish a sound and practical conceptual foundation for formulating and evaluating impact significance determination approaches.It addresses the nature (what is impact significance?), the core characteristics (what are the major properties of significance determination?), the rationale (why are impact significance determinations necessary?), the procedural and substantive objectives (what do impact significance determinations seek to achieve?), and the process for making impact significance judgments (how is impact significance determination conducted?). By identifying fundamental attributes and key distinctions associated with impact significance determinations, a basis is provided for designing and evaluating impact significance determination procedures at both the regulatory and applied levels. 相似文献
117.
118.
黏胶基活性炭纤维对三氯一氟甲烷的吸附性能 总被引:1,自引:0,他引:1
采用动态吸附试验,利用自制的试验装置研究了黏胶基活性炭纤维〔Viscose-Based Activated Carbon Fibre (Viscose-Based ACF)〕对三氯一氟甲烷(CFC-11)气体的吸附效果. 在进口ρ(CFC-11)为0.5~8.0 mg/L,空塔气速为0.2 m/s,气体体积流率为0.72 m3/h的条件下,计算出黏胶基活性炭纤维对CFC-11气体的吸附,容量为0.788 g/g,传质区高度为0.077 2 m,全床层饱和度为65.47%,并作出活性炭纤维(AFC)的穿透曲线. 用Freundlich方程对等温吸附曲线进行拟合显示,进口ρ(CFC-11)在0.5~8.0 mg/L时,Freundlich方程较好地拟合了等温吸附曲线,且便于实际计算. 相似文献
119.
Input–output modelling is a useful tool in policy analysis and economic planning. This methodology is used to detect the inter-industry linkages known as forward and backward linkages. Examination of these measures provides one mechanism for identifying “key” or “leading” sectors. The main objective of this paper is to measure the linkages of the mining and quarrying industry in the European Union (EU) and to determine if any of the industry subsectors can be considered key sectors. The paper shows that three subsectors can be considered key sectors: the mining of coal and lignite and extraction of peat in Germany; mining of metal ores in Sweden; and other mining and quarrying in Austria, Denmark and Spain. These sectors are more stimulated by overall industry growth than other sectors and have greater impacts in terms of investment expenditures on the national economy than other sectors. The values of the forward and backward linkages show that the mining and quarrying is an industry that would be stimulated by an increase in a regional economy's production more than other sectors, while an increase in the mining and quarrying industry's output would not stimulate this regional economy more than an increase in other sectors. 相似文献
120.
本研究选取山西省具有代表性的焦化厂,通过在废气排放烟囱上采集燃烧室废气和装煤/出焦废气,初步研究了煤焦化过程甲烷排放特征。结果显示燃烧室废气中CH4占∑(CH4+NMHC)的比例远高于装煤和出焦废气。基于EPA AP-42排放因子的计算方法,煤焦化三个工段的CH4排放因子为228.5±56.1g/t。结合中国机械炼焦炉焦炭产量,2004年中国机械炼焦CH4排放为0.03Tg/a,占中国总CH4排放的0.1%,可能是山西省除煤炭开采外的重要甲烷排放源,该值还需再进一步的工作中完善和验证。 相似文献