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61.
随着近些年振动试验技术的快速发展,对于振动试验数据的保存、管理和统计提出了更高的要求。鉴于此,附属于试验室信息管理系统的振动试验数据管理系统作为振动试验有效的管理工具,必然会成为提升试验室振动试验能力、规范试验技术的有效工具。  相似文献   
62.
The paper tests the material Kuznets Curve (MKC) hypothesis with regard to aluminium consumption for 20 high-income countries over the period 1970 to 2009. The test is based on the suggestion of Narayan and Narayan (2010). Various unit root and cointegration tests are applied. The aluminium and GDP series are found to be integrated of order one and cointegrated. Additionally, the Blundell–Bond system generalized methods-of-moments (GMM) is employed to conduct a panel causality test in a vector error-correction mechanism (VECM) setting. Unidirectional causality running from real per capita GDP to the aluminium intensity is uncovered in both the short-run and long-run. While controlling for structural shocks, the MKC hypothesis is found to hold at individual levels for Austria, Canada, Denmark, Finland, Greece, Italy, Japan, and United Kingdom as well as for the whole panel. A 1% increase in GDP generates an increase of 0.87% in metal intensity in the short-run and a fall of 0.82% in the long-run for the panel.  相似文献   
63.
排放污染物总量核定是排放污染物总量控制中的一项难度很大的基础工作。文章针对目前排污总量核定中存在的环境监测硬件投入不足、体系不完善、可操作性不强、法律效力不够和规范化管理不力等问题 ,提出了排污总量核定应形成一项基本的工作制度 ,应加强排污总量核定体系的运行和监督管理。  相似文献   
64.
Abstract

The importance of field surveys to provide data on acute pesticide hazards is discussed. The types of questions which small field surveys of pesticide exposure should answer are presented. In addition to protective clothing, the value of distance, time, and personal hygiene in reducing exposure are considered. Finally, the importance of an adequate data base for the development of protocols and guidelines for public protection is discussed.  相似文献   
65.
Abstract

The use of agrochemicals like crop protecting agents, veterinary disinfectants, and wood preservatives may result in (un)intentional exposure of the environment, animals and man. This paper deals with current testing strategies to assess the potential health risks for humans exposed to these chemicals during production or application or via consumption of foods containing pesticide residues.

Principles and procedures for safety assessment of pesticide residues in food as developed by WHO/FAO are described. Different types of toxicity studies in mammalian test animal species are discussed and a strategy is outlined in order to characterize the toxicity profile of a compound and the relationship between applied doses and adverse effects. Safety testing of agrochemicals should be carried out in relation to its intended use, and in particular attention will be paid to toxicity testing of residues of pesticides in food. Extrapolation of results from animal studies to humans and the use of safety factors is discussed.

Besides the use of animal protocol studies for safety testing of agrochemicals, the potential use of in‐vitro models derived from organs and tissues of animals is discussed. Data on the in‐vitro metabolism of thiabendazole, aldicarb and alachlor are discussed in order to demonstrate that such data may complement or partly substitute whole animal experimentation.

Principles and procedures for safety testing of residues of agrochemicals in food as applied during the last three decades, constitute a ‘safety‐first’ approach, providing sufficient safety margins for the consumer of foods which may contain low levels of residues of agrochemicals.  相似文献   
66.
重庆市环境质量自动监测(控)系统网络集成设计   总被引:5,自引:0,他引:5  
针对目前重庆市环境空气质量自动监测现状,结合自动监控系统设计先进技术和国内部分省市已建成的环境信息监控网络的先进经验,对重庆市环境空气自动监测监控系统的建设进行设计,并介绍了环境空气质量自动监测监控系统的组成和实现的功能.现有的自动监测系统存在不同类型设备、通讯方式落后等问题,建设重庆市环境质量自动监控系统的思路是采用GPRS/CDMA/ADSL为主的数据通信传输技术,建立通信控制和信息集成系统,把重庆市环境空气、水、噪声自动监测系统进行系统化的集成,设计成一个完善的环境信息自动化动态监控平台.  相似文献   
67.
环境监测预警体系只有依靠计算机信息系统才能发挥其作用,根据预警体系的特点、内容以及要实现的功能,论述了信息系统硬件建设和软件建设的基本要求、系统的组成和系统实现的方法。  相似文献   
68.
分析了目前环境监测部门的数据传输现状,设计了基于VPN互联网络的环境质量数据层级化直报业务系统,介绍了网络直报系统的业务模型、数据审核和存储策略、系统功能设计及其应用等。  相似文献   
69.
Adaptive management is an approach to recurrent decision making in which uncertainty about the decision is reduced over time through comparison of outcomes predicted by competing models against observed values of those outcomes. The National Wildlife Refuge System (NWRS) of the U.S. Fish and Wildlife Service is a large land management program charged with making natural resource management decisions, which often are made under considerable uncertainty, severe operational constraints, and conditions that limit ability to precisely carry out actions as intended. The NWRS presents outstanding opportunities for the application of adaptive management, but also difficult challenges. We describe two cooperative programs between the Fish and Wildlife Service and the U.S. Geological Survey to implement adaptive management at scales ranging from small, single refuge applications to large, multi-refuge, multi-region projects. Our experience to date suggests three important attributes common to successful implementation: a vigorous multi-partner collaboration, practical and informative decision framework components, and a sustained commitment to the process. Administrators in both agencies should consider these attributes when developing programs to promote the use and acceptance of adaptive management in the NWRS.  相似文献   
70.
Accurate prediction of municipal water demand is critically important to water utilities in fast-growing urban regions for drinking water system planning, design, and water utility asset management. Achieving the desired prediction accuracy is challenging, however, because the forecasting model must simultaneously consider a variety of factors associated with climate changes, economic development, population growth and migration, and even consumer behavioral patterns. Traditional forecasting models such as multivariate regression and time series analysis, as well as advanced modeling techniques (e.g., expert systems and artificial neural networks), are often applied for either short- or long-term water demand projections, yet few can adequately manage the dynamics of a water supply system because of the limitations in modeling structures. Potential challenges also arise from a lack of long and continuous historical records of water demand and its dependent variables. The objectives of this study were to (1) thoroughly review water demand forecasting models over the past five decades, and (2) propose a new system dynamics model to reflect the intrinsic relationship between water demand and macroeconomic environment using out-of-sample estimation for long-term municipal water demand forecasts in a fast-growing urban region. This system dynamics model is based on a coupled modeling structure that takes into account the interactions among economic and social dimensions, offering a realistic platform for practical use. Practical implementation of this water demand forecasting tool was assessed by using a case study under the most recent alternate fluctuations of economic boom and downturn environments.  相似文献   
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