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1.
Experiments were performed in a 1.5 MW pilot-scale furnace to investigate the differences between air- and oxy-fired flame behavior from a pulverized coal oxy-research burner designed for flexible operating conditions. The flame behavior was characterized by recording video images of the flames and by measuring radiation intensity along the flame length. Various strategies relating air- and oxy-fired operation of the burner primary register were investigated where the oxy-fired burner primary mass, momentum and velocity were matched to the air-fired conditions. Matching either burner primary mass or momentum under oxy-fired conditions with air-fired conditions resulted in a flame stabilized within the quarl. Matching primary velocity with air-fired conditions resulted in a detached flame indicating a delay in flame ignition for the oxyfired conditions. A decrease in primary velocity of 13% was necessary in order to stabilize a flame within the quarl similar to the air-fired case. Additional experiments also showed a flame could be stabilized with no oxygen enrichment of the primary (~3 vol.%, dry O2 in the primary). Experiments where oxygen was injected at the burner face indicated injection at the boundary of the primary and secondary flow paths strongly attach a flame and injection at the coal rich primary flow path increased the radiative intensity of the flame.  相似文献   

2.
Today, U.S. corporations are discovering the merit of combining the principles of total quality environmental management (TQEM) into their measurement and communications programs. This approach has been particularly productive in the permitting process that is necessary for starting, expanding, or sustaining plant operations—a procedure that can easily be thwarted in the absence of a prominent and aggressive communications component. The need to benchmark and measure such a communication program'S progress is critical both for internal management and for environmental regulators concerned that an applicant demonstrate a high degree of public involvement.  相似文献   

3.
Industrial ecology is a new multidisciplinary field of study requiring that economic activity be integrated with, and have minimal impact on, surrounding natural systems. This systems-based approach is beginning to be implemented in private firms through the development of Design for Environment (DFE) methodologies and tools which support the integration of technological and environmental considerations in all economic activities. As part of this development process, a matrix system is proposed by the author by which the environmental and energy costs embedded in materials as used in generic applications may be identified, facilitating environmentally and economically efficient selection of materials. This Material Environmental Evaluation Matrix is supported by checklists which inform the evaluation process. A set of completed matrices for major materials in common applications forms the basis for an Environmentally Efficient Materials Database (EEMD). Once completed, the EEMD would inform consumers, product and process designers, business planners and managers, regulators and government purchasers, public interest groups, and others in their choice of optimal, environmentally and economically efficient, material options.  相似文献   

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5.
This article argues that much of the economic criticism of the Integrated Programme for Commodities has been based on outdated and simplistic models and that fears of ‘dirigisme’ and price raising derive from a misunderstanding of the fundamental focus of the IPC on price stabilization. Moreover, the proposed IPC would, it is argued, generate benefits significantly in exces of its costs, which themselves have often been exaggerated. The article concludes by arguing that compensatory finance should be viewed as complementary to, not competitive with, the IPC.  相似文献   

6.
在介绍美国农药环境风险评估的概念、分级、地下水农药监测情况及水资源的立法保护等基础上,重点阐述了美国环保署在农药登记管理过程中使用的2个地下水风险评估模型,即SCI-GROW和PRZM-GW模型。SCI-GROW是以好氧条件土壤半衰期和土壤有机碳分配系数为自变量的经验线性回归模型,而PRZM-GW则是描述农药在土壤中运动的一维、有限差分模型。本文通过对美国环保署这2个特点鲜明的模型的介绍,希望能为我国的农药地下水风险评估及模型的开发提供一个新视角。  相似文献   

7.
Benchmarking is a powerful management technique that can help improve an organization's environmental performance on a number of dimensions. Benchmarking is not a cookbook solution but a systematic process of searching for the organization that is the best at a given process (“best-in-class”) and continually adopting or adapting new processes to accelerate improvement. As a continual process including planning, analysis, integration, action, and maturity phases, benchmarking should be integrated into the planning stage of the management system. Once processes are strategically identified, they can be improved within the company's Total Quality Management program. Many benefits, such as teamwork and job satisfaction, accompany benchmarking, but the greatest companywide advantage is becoming more competitive. Finding a suitable partner is crucial to the success of the benchmarking process. This article shows the traditional one-on-one approach is the most effective because it saves time and money that allows organizations to learn from each other. In addition, examples of where benchmarking partners may be found, as well as several success indicators in the benchmarking process, are presented. Since the ultimate intent of benchmarking is positive change, the difference between reengineering and continuous performance improvement and the role benchmarking plays in each is also discussed.  相似文献   

8.
Securing flows for environmental purposes from an already fully utilized river is an impossible task--unless users are either coerced into freeing up water, or offered incentives to do so. One sensible strategy for motivating users to liberate volumes is to offer them economic compensation. The right amount for that compensation then becomes a key environmental management issue. This paper analyses a proposal to restore and maintain ecosystems on a stretch of the Río Conchos in northern Mexico, downstream from a large irrigation district that consumes nearly all local flows. We present here estimates of environmental flow requirements for these ecosystems and compute compensation figures for irrigators. These figures are derived from crop-specific irrigation water productivities we statistically estimate from a large set of historical production and irrigation data obtained from the district. This work has general implications for river ecosystem management in water-stressed basins, particularly in terms of the design of fair and effective water sharing mechanisms.  相似文献   

9.
旅游商品发展对策思考   总被引:4,自引:1,他引:4  
发展旅游商品是近年来中国旅游经济理论和实践中的热点问题之一,本文提出并论述了制定旅游商品发展规划,培育开发主体,在市场调研基础上科学开发,有效组织生产,市场建设与规范和宣传促销六大对策措施。  相似文献   

10.
11.
A method for evaluating areas for national park status   总被引:1,自引:0,他引:1  
A procedure for evaluating different areas as national parks based on a scoring system is proposed. A National Park Evaluation Form (NPEF) evaluating natural, cultural, and recreational resources in accordance with international criteria for national parks is presented. The evaluation points given to an area indicate the possibility of the area becoming a national park. In this method, subjectivity and bias have been minimized by a special application of the Delphi technique. The method outlined here could help in the efforts of selecting and establishing national parks in many countries.  相似文献   

12.

Call for Papers

Rolex Calls for Entries to 11th Awards for Enterprise and Extends Deadlines for All Countries  相似文献   

13.
We performed a sociocultural preference assessment for a suite of ecosystem services provided by the Kiamichi River watershed in the south‐central United States, a region with intense water conflict. The goal was to examine how a social assessment of services could be used to weigh tradeoffs among water resource uses for future watershed management and planning. We identified the ecosystem services beneficiaries groups, analyzed perception for maintaining services, assessed differences in the importance and perceived trends for ecosystem services, and explored the perceived impact on ecosystem services arising from different watershed management scenarios. Results show habitat for species and water regulation were two ecosystem services all beneficiaries agreed were important. The main discrepancies among stakeholder groups were found for water‐related services. The identification of potential tradeoffs between services under different flow scenarios promotes a dynamic management strategy for allocating water resources, one that mitigates potential conflicts. While it is widely accepted the needs of all beneficiaries should be considered for the successful incorporation of ecosystem services into watershed management, the number of studies actually using the sociocultural perspective in ecosystem service assessment is limited. Our study demonstrates it is both possible and useful to quantify social demand of ecosystem services in watershed management.  相似文献   

14.
瑞典的生态税收规模较大,种类较多,并具有特色,主要是对能源及其他与环境有关的税基的征税。近年我国能源的消耗量逐渐增大,以及废旧电池等对环境污染较大,应该借鉴瑞典的经验,开征独立的环境保护税,并配合其他措施,将取得的税收用于环境的保护。  相似文献   

15.
Incorporation of aesthetic considerations in the process of landscape planning and development has frequently met with poor results due to its lack of theoretical basis, public involvement, and failure to deal with spatial implications. This problem has been especially evident when dealing with large areas, for example, the Adirondacks, Scenic Highways, and National Forests and Parks. This study made use of public participation to evaluate scenic quality in a portion of the Niagara Escarpment in Southern Ontario, Canada. The results of this study were analyzed using thevisual management model proposed by Brown and Itami (1982) as a means of assessing and evaluating scenic quality. Themap analysis package formulated by Tomlin (1980) was then applied to this assessment for the purpose of spatial mapping of visual impact. The results of this study illustrate that it is possible to assess visual quality for landscape/management, preservation, and protection using a theoretical basis, public participation, and a systematic spatial mapping process.  相似文献   

16.
Compared to continental areas, most islands have exceptionally long coastlines relative to their total land area. For this reason, islands are uncommonly vulnerable to problems associated with coasts. The future of the human inhabitants of many island states depends intrinsically on the sustainable management of their coasts, a challenge which grows more pressing as island populations increase and the associated demands on island coastlines change and grow. These issues are presented and discussed in this article. The mechanics of the sustainable management of island coasts is itself an important issue. At the national or local level, management is plagued by problems of insufficient and/or imprecise data and understanding that may lead to inappropriate solutions that even exacerbate the problems they are intended to solve. At an inter-governmental or international level, problems associated with the understanding of island environments need to be resolved before optimal management strategies can be developed. This article presents a brief explanation of the nature of coastal vulnerability on oceanic islands, followed by a discussion of several key problems associated with their sustainable development and the role of human and non-human factors in recent environmental change. It discusses the future of oceanic island coasts in the face of both internal and external threats to their sustainable management. It concludes with a blueprint for their survival.  相似文献   

17.
Economic sustainability or intergenerational equity entails maintaining social well-being by decisions about investments in different types of assets. Under certain conditions, consumption can be sustained by depleting resources, or various kinds of natural capital, while building up other kinds of capital. Theoretically, the choices involve the use of a set of accounting prices. The question becomes one of finding and implementing accounting prices that express the roles of the various capital goods in achieving the objective of the economy.Hartwick's rule holds that an economy can be sustained if the value of the total, net investment in the economy, evaluated at those accounting prices, is zero. The rule applies to a special, abstract economic model which expresses a social objective different from the discounted-utilitarian objective on which national accounting is based. Different objectives give rise to different accounting prices. Because the prices may not be right, the zero net-investment rule using available national-accounting prices cannot generate a condition for sustaining an economy.Still, environmental accounting is a tool which, used prudently, can make an important contribution to social decision-making. This paper expands upon these ideas by discussing the incorporation of natural resource and intangible environmental costs and benefits into green accounting at the firm as well as the economy level. Common techniques of mine valuation and standard corporate accounting are the bases for this extension to the valuation of and accounting for decisions concerning the environment.  相似文献   

18.
Material efficiency improvement saves energy and reduces the consumption of primary resources and reduces the volume of waste. In this article an approach for analysing the potential for material efficiency improvement is proposed and discussed. In this approach the product functions performed by the materials and various improvement measures are taken into account. The potential for material saving and associated energy saving is assessed and evaluated economically. In this paper the approach is tested in an analysis of the potential for material efficiency improvement with respect to plastic packaging in the Netherlands. The technical reduction potential is found to be 34 ± 7% (157 ± 30 ktonne virgin plastics). Realization of this potential would improve the energy efficiency of the lifecycle of plastic packaging by 31% (10 PJ in 1988). From our study we conclude that our approach can indeed be used to investigate the potential for material efficiency improvement. However, a reliable technical and particularly an economical assessment of reduction measures cannot be made until more detailed data become available.  相似文献   

19.
The author uses two publications, Fighting Poverty in the US and Europe (Alesina and Glaeser) and Poetry magazine, to underscore the important role that educational institutions play in developing a person’s political philosophy and imagination. European nations, for instance, have better funded social welfare programs than the US because their system of public education incorporates more liberal or left-leaning teachings into their standard curricula. The author sees implications for a more intentional approach to education in the US for those who are interested in changing the food system. If American educational institutions viewed their role as producing food competent citizens, he argues, then we would be more successful in addressing obesity, promoting a more sustainable food system, and even reducing poverty. Food system activists, dieticians and nutritionists, parents, and elected officials should take a more aggressive position with educational institutions to develop programs, services, and curricula capable of achieving these ends.  相似文献   

20.
In the past much of the training effort of public agencies was not aimed at specific job vacancies or at areas of skill shortages. In contrast, targeted training aims to provide identified disadvantaged groups with training to enable them to compete for identified job vacancies. This paper looks at the success of targeted training through three examples, at how its effectiveness can be improved, and the role of local government in initiating and developing such training.  相似文献   

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