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691.
Using integrating NO2 diffusion dosimeters, personal, indoor and outdoor exposures were measured for nine families in Topeka, Kansas. NO2 exposures in homes that used gas for cooking were clearly different from those in homes that used electricity. The gas-cooking homes had indoor levels three times the outdoor levels. Members of the gas-cooking households had levels twice those of electric-cooking families and twice the outdoor levels. A linear model that includes outdoor concentrations and stove types explains 77% of the variance in observed NO2 exposure. The differential NO2 exposures in homes with and without gas stoves should be considered in epidemiologic studies of the health effects of air pollution.  相似文献   
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By mid-1990 the National Park Service (NPS) must present to Congress recommendations for managing overflights of at least ten national parks. The authors examine the potential role of formal negotiation in setting overflight policy in these parks by reviewing the overflight controversy at Grand Canyon National Park (GCNP). Regulations controlling overflights of the GCNP are only now being implemented after a 17-year conflict that culminated in a congressionally mandated solution. The authors review this controversy and find that, contrary to common perception, the number of park visitors bothered by overflights is not small but roughly equals the number of airborne visitors (up to 450,000 per year). On the basis of this investigation, the authors determine that formal negotiation would have been an appropriate policy-making process because of the clearly defined and limited number of parties and issues involved. Considering the number of park visitors that will continue to be affected by this issue, the authors conclude that formal negotiations should be considered for overflight problems involving other parks. Such negotiations should be park-specific. Differences in park size, extent of the problem, and parties involved would prohibit park-wide negotiations.This article has been adapted from Tourist Flights over the Grand Canyon: The Potential for Negotiated Solutions to Similar Problems, Analysis and Management, October 30, 1987. The opinions expressed in this article are those of the authors; they are not meant to represent the views of the organizations with which the authors are associated.  相似文献   
694.
ABSTRACT: This paper presents a summary of the findings and recommendations of the studies of severe, sustained drought reported in this special issue. The management facilities and institutions were found to be effective in protecting consumptive water users against drought, but much less effective in protecting nonconsumptive uses. Changes in intrastate water management were found to be effective in reducing the monetary value of damages, through reallocating shortages to low-valued uses, while only water banking and water marketing, among the possible interstate rule changes, were similarly effective. Players representing the basin states and the federal government in three gaming experiments were unable to agree upon and effect major changes in operating rules. The conclusions are (1) that nonconsumptive water uses are highly vulnerable to drought, (2) that consumptive uses are well-protected, (3) that drought risk is greatest in the Upper Basin, (4) that the Lower Basin suffers from chronic water shortage but bears little drought risk, (5) that opportunities exist for win-win rule changes, (6) that such rule changes are extremely difficult to make, and (7) that intrastate drought management is very effective m in reducing potential damages.  相似文献   
695.
Conflicts between the goals of having clean air and economic development are widespread. This paper discusses the conceptual and mathematical development of a linear programming optimization model and an interative solution procedure to determine optimal economic development strategies to promote employment subject to various contexts which limit air pollution carrying capacity. Three cases are formulated: (1) maximizing employment subject to ambient concentration constraints, (2) maximizing employment subject to emissions constraints, and (3) minimizing emissions subject to employment constraints. Empirical relationships using Census and pollutant inventory data describe a conceptual urban system, so that indirect and induced impacts of development strategies are also included. The modeling incorporates both point and nonpoint sources, and is shown to be adaptable for nonreactive emissions.  相似文献   
696.
The technology transfer of flood warning systems offers a large potential for reducing human losses and property damage in flood-prone regions; much of the technology and methodology is readily transferable from developed countries and “appropriate” for developing countries. This paper examines some community folk warning systems in the United States that could be incorporated into a rational strategy for technology transfer. It discusses why official organized systems should not be relied on completely and how participation in and transfer of highly cost-effective and reliable community warning systems by development assistance agencies could greatly benefit the people as well as the governments of developing countries.  相似文献   
697.
ABSTRACT: At a time when productive water resources research is essential to protecting the quality of and wisely using our limited water resources, pervasive trends toward consumerism, fiscal restraint, centralized management, and using research for other social objectives threaten research productivity. The research prioritization and management structure that these trends have created was examined in the microcosm of its application at the Utah Water Research Laboratory. The result indicated that ephemeral prioritization and the failure of research users to target researchers to their own particular needs is diluting productivity. Incremental research prioritization and greater use of advisory councils in facilitating user-researcher interaction are suggested as corrective approaches, but the only firm conclusion at this point in time must be that empirical studies of the performance of alternatives in research management structure are solely needed.  相似文献   
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Four methods for estimating the uncertainties in air pollution measurements are outlined. The approaches are: analytical solution-approximation; application of distribution theory; experimentation; and simulation. The advantages and disadvantages of each method are illustrated using data from High-Volume air samplers, the instrument most commonly used for monitoring ambient concentrations of airborne particles.Dr Evans is Assistant Professor of Environmental Science and Mr Kinney is a doctoral candidate in the Department of Environmental Science and Physiology, Harvard School of Public Health. Dr Cooper is at the Manufacturing Research Laboratory, Thomas J. Watson Research Center, IBM, Yorktown Heights, NY.  相似文献   
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