共查询到20条相似文献,搜索用时 15 毫秒
1.
Domnita Fratila 《Journal of Cleaner Production》2009,17(9):839-845
One of the main environmental pollution sources related to machine building industry is the huge amount of cutting fluids which are supplied during the machining processes. In order to avoid the problems induced by cutting fluids' usage, considerable progress has been recently made in the field of near-dry machining (NDM). Converting conventional processes to minimal quantity lubrication (MQL) methods imposes new tasks' classification within the tribiological system in order to guarantee the process safety and product quality. This paper gives an overview on some requirements to be considered for a successful MQL application into industrial practice. Its last part is focused on the evaluation of NDM effects on the gear milling process efficiency, with respect to hob wear, surface quality, cooling effect, and environment protection. 相似文献
2.
Paul Hudson 《Mitigation and Adaptation Strategies for Global Change》2018,23(7):1019-1038
Risk-based insurance is a commonly proposed and discussed flood risk adaptation mechanism in policy debates across the world such as in the United Kingdom and the United States of America. However, both risk-based premiums and growing risk pose increasing difficulties for insurance to remain affordable. An empirical concept of affordability is required as the affordability of adaption strategies is an important concern for policymakers, yet such a concept is not often examined. Therefore, a robust metric with a commonly acceptable affordability threshold is required. A robust metric allows for a previously normative concept to be quantified in monetary terms, and in this way, the metric is rendered more suitable for integration into public policy debates. This paper investigates the degree to which risk-based flood insurance premiums are unaffordable in Europe. In addition, this paper compares the outcomes generated by three different definitions of unaffordability in order to investigate the most robust definition. In doing so, the residual income definition was found to be the least sensitive to changes in the threshold. While this paper focuses on Europe, the selected definition can be employed elsewhere in the world and across adaption measures in order to develop a common metric for indicating the potential unaffordability problem. 相似文献
3.
采用AERMOD和估算模式两种预测模式对同一生活垃圾填埋场进行了预测。比较两种预测结果可以看出,在污染源、预测范围、运行周期相同的情况下,敏感点处的落地浓度均与排放源强呈正比,与距离呈反比。预测结果同时说明,估算模式是一种保守的预测模式,其预测结果比AERMOD模式大,可作为进一步预测模式的有效补充。 相似文献
4.
《Environmental Science & Policy》2007,10(3):177-184
This study compares multiple criteria analysis (MCA) assisted decisions and unaided decisions in an environmental management context. It involved 55 decision makers in Queensland, Australia, who used MCA techniques to evaluate environmental projects alongside their own intuitive approaches under the Australian Natural Heritage Trust (NHT) program. The NHT is Australia's largest environmental program funded over A$ 2.5 billion over 10 years. The study assessed decision maker learning and perceptions of MCA's overall usefulness. It was found that MCA produced markedly different results to unaided evaluations. Feedback from decision makers typically showed that unaided decisions did not make explicit use of evaluation criteria. Even though most decision makers were unwilling to change their choices following the use of MCA, they found it a helpful input to their decision procedure. The majority of decision makers supported the adoption of MCA to make future investment decisions under the NHT program. 相似文献
5.
6.
7.
Orthogonal machining of single-crystal and coarse-grained (i.e., grain size considerably larger than the uncut chip thickness) materials has been a subject to many studies in the literature. The first part of this paper presents background on machining single-crystal materials, including experimental and modeling attempts. The second part briefly describes more recent modeling results from the authors, and presents new experimental results on planing and plunge-turning of single-crystal and coarse-grained aluminum using diamond tools. The experiments indicate that (1) cutting across grains of a coarse-grained aluminum workpiece produces distinctly varying forces and surface roughness from one grain to another, (2) plunge-turning and planing of single crystal aluminum provide equivalent force data for large rake angles, (3) forces alter between two distinct levels while cutting single crystals with small rake angles, and (4) with small rake angles, subsurface damage on single-crystal aluminum is extensive, reaching depths comparable to the uncut chip thickness. 相似文献
8.
Three- dimensional laser machining of structural ceramics such as alumina (Al2O3), silicon nitride (Si3N4), silicon carbide (SiC) and magnesia (MgO) was carried out using a 1.06 μm wavelength pulsed Nd:YAG laser. The rate of machining predicted in terms of material removed per unit time (mg/s) increased with an increase in heating rate (K/s). A thermal model based on temperature dependent absorptivity and thermophysical properties, in addition to conduction, convection and radiation based heat transfer, was developed to predict material removal rate. Predicted values were compared with actual measurements made from machined cavities. Such a study would enable advance predictions of the laser processing conditions required to machine cavities of desired dimensions. 相似文献
9.
10.
根据分形理论与系统自组织理论,本文分析了中国洪涝灾害及其灾情的分形与自组织结构特征。研究发现,中国洪涝灾害及其灾情的分形与自组织结构特征是客观存在的,在此基础上,建立了中国洪涝灾害灾情的标度一频度关系式,并构建了中国洪涝灾害死亡人数的自组织模型。 相似文献
11.
环境监测是环境保护的基础,环境监测为环保工作提供了科学依据和技术支持,环境监测技术使人们能够更为及时、有效地监测、判断环境状况,进而探究环境保护的方法和途径,明确环保工作的方向和目标,制定科学、正确的环保制度和政策。在环境问题日益严重的现代社会,环境监测技术已经成为一项不可或缺的现代科学技术。本文首先分析了环境监测的涵义和发展过程,然后分析了环境监测技术的发展概况以及未来发展趋势。 相似文献
12.
《Environmental Science & Policy》2008,11(4):329-335
This article introduces a tradeable permit system concerning flood mitigation. The proposed economic instrument aims at encouraging collaboration between upstream and downstream zones and that between public and private sectors on flood management. It can also serve as a channel for burden-sharing among flood management, spatial planning and conservation easement in terms of both finance and strategies. The existing research and applications on tradeable permits for environmental management, together with principles of flood management, lay the groundwork for developing the tradeable flood mitigation permit (TFMP) system. 相似文献
13.
With more than 130,000 organizations worldwide certified according to ISO requirements, business people, regulatory authorities and other stakeholders have reason to wonder whether the purpose of ISO 14001, which is to help improve environmental performance, is being fulfilled. There is a growing body of literature attempting to answer this question. The results, however, are inconclusive.This meta-study analyzes a pool of 23 studies connecting environmental performance to environmental management systems. It shows that the reason that earlier studies arrived at mixed conclusions is twofold. Firstly, there is no agreement on what environmental performance is or how to measure it. Secondly, there is neither clarity nor agreement about how or why environmental management systems are expected to aid performance. It is therefore unclear whether the mechanisms that lead to improvement are expected to be the same for all companies or dependent on each implementation.The authors conclude that it is more fruitful to research how environmental management systems affect performance, rather than whether they do so or not. The recommended starting point for such studies is environmental performance as each organization defines it. This in turn implies a case by case approach and a need for much more research in the field. 相似文献
14.
海洋环境文化是海洋文化和环境文化的一个分支,其建设状况对海洋环境保护影响甚大.本文从引入海洋环境文化的概念入手,探析其内涵及重要性,分析了海洋环境文化与海洋经济的辩证关系,并就海洋环境问题,从海洋环境文化层面剖析原因,提出了海洋环境文化建设的对策思路. 相似文献
15.
Using a revised version of a previously published expert classification system, a database of potential Sustainable Flood Retention Basins has been developed for Scotland. The research shows that the majority of small and former (often old) drinking water reservoirs are kept full and their spillways are continuously in operation. Utilising some of the available capacity to contribute to flood control could significantly reduce the costs of complying with the European Union Flood Directive. Furthermore, the application of a previously developed classification model for Baden in Germany for the Scottish data set showed a lower diversity for basins in Scotland due to less developed infrastructure. The classification system appears to be robust and has the potential, with minor modifications, to be applied across Europe. The principle value of this approach is a clear and unambiguous categorisation, based on standard variables, which can help to promote communication and understanding between stakeholders. 相似文献
16.
Aerosols and environmental pollution 总被引:2,自引:0,他引:2
The number of publications on atmospheric aerosols has dramatically increased in recent years. This review, predominantly
from a European perspective, summarizes the current state of knowledge of the role played by aerosols in environmental pollution
and, in addition, highlights gaps in our current knowledge. Aerosol particles are ubiquitous in the Earth’s atmosphere and
are central to many environmental issues; ranging from the Earth’s radiative budget to human health. Aerosol size distribution
and chemical composition are crucial parameters that determine their dynamics in the atmosphere. Sources of aerosols are both
anthropogenic and natural ranging from vehicular emissions to dust resuspension. Ambient concentrations of aerosols are elevated
in urban areas with lower values at rural sites. A comprehensive understanding of aerosol ambient characteristics requires
a combination of measurements and modeling tools. Legislation for ambient aerosols has been introduced at national and international
levels aiming to protect human health and the environment. 相似文献
17.
18.
19.
Using CALFED as a case study, this article explores problems with a conventional conceptual framework for understanding environmental crises. That framework, which both derives from and influences legal regimes, posits that environmental managers should fulfill the protective requirements of environmental laws, but should discern exactly where the brink of non-compliance lies and should allow or even facilitate resource consumption right up to that perceived edge. In contexts like CALFED, where environmental conditions are uncertain and institutions are unavoidably somewhat rigid and inflexible, that approach will function poorly, and this article therefore articulates an alternative conceptual approach capable of improving the reliability of resource allocation patterns. That alternative approach posits that in conditions of scarcity, environmental uncertainty, and rigidly constraining environmental laws, the intensity and reliability of resource use are likely to be inversely proportional, and reducing the intensity of consumptive use will tend to increase the stability and reliability of consumptive patterns. 相似文献