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111.
Guo Ya-kun Wen Xian-yun Institute of Hydraulic Research Chengdu University of Science Technology Chengdu P.R.China 《水动力学研究与进展(B辑)》1993,(1)
In this paper,using complex functional theory,the authors turn the potentialflow around the surface irregularities in a pressure conduit and semi-infinite platforms intoDirichlet problem.Based on Schwarz formula and by the application of Plemelj's formula,theauthors change the problem into the integration of a Cauchy boundary integral equation in theflow plane through the substitution of variables.Using numerical integration,the authors obtainthe velocity distribution and pressure coefficient along surface irregularities and platforms.Thephysical concept of this method is clear,the convergent speed is rapid and the computative effi-ciency is high.The calculated values agree well with the measured results.It is an effective andsimple method in solving potential flow. 相似文献
112.
Robert J. Hershock Charles D. Cowman Douglas Peters 《Journal of Product Innovation Management》1994,11(2):95-104
A growing awareness of workplace hazards and identification of airborne contaminants, coupled with a changing safety and health regulatory environment, created an unexpected demand for new and innovative respirators in the early 1980s. 3M's Occupational Health and Environmental Safety Division broke new ground by taking the team concept further than ever before in the company. The division's Action Teams successfully designed, built and introduced products in less than half the time it would have taken previously. Robert Hershock, Charles Cowman and Douglas Peters describe how 3M learned important lessons about team selection, training, performance and motivation, the importance of project sponsors, and the role of middle management. 相似文献
113.
Carla J. Robinson 《The Review of Black Political Economy》1991,19(3-4):85-109
Atlanta has the reputation of being a city of opportunity for blacks. However, in Atlanta, as well as in other cities across
the nation, the nexus of racism and economic discrimination has resulted in disparities between the housing status of blacks
and whites. This article examines racial disparities in the Atlanta housing market. It begins by tracing recent trends in
the Atlanta-area economy and by providing background information on the local housing market. It then discusses the roles
of the federal Home Mortgage Disclosure Act of 1975 and Community Reinvestment Act of 1977 in the efforts of local groups
to reduce racial disparities in the housing market. The final section discusses recent local developments that might lead
to improvements in the housing status of black Atlantans. 相似文献
114.
Gregory J. Werden Andrew S. Joskow Richard L. Johnson 《Managerial and Decision Economics》1991,12(5):341-352
The literature on industrial organization contains very little direct evidence on the effects of actual mergers. This study estimates the effects of two recent airline mergers approved by the Department of Transportation over the objection of the Department of Justice. The merger of TWA and Ozark appears to have caused a slight increase in fares and a far greater reduction in service on city pairs out of St Louis. The merger of Northwest and Republic appears to have caused a significant increase in fares and a significant reduction in overall service on city pairs out of Minneapolis-St Paul. 相似文献
115.
116.
Whilst the local multiplier impacts of the annual operation of universities has been the subject of intensive research, the economic impacts of capital construction projects have been almost completely ignored. This paper presents the results of detailed analysis of capital projects at Lancaster University in 1993-The reasons for the radically different annual operation and construction multipliers estimated in the Lancaster study are examined. Despite the smaller size of construction multipliers it is argued that it is a serious mistake to estimate local construction multipliers by making simplifying assumptions on the size of the key parameters in the multiplier equations. 相似文献
117.
Manfred J. Holler 《Quality and Quantity》1993,27(1):103-115
In this paper we will discuss some peculiarities of the Nash equilibrium which are at odds with its standard applications: (a) the underlying dynamic interpretation, (b) the incentive independency if equilibria are mixed, and (c) the unprofitability if equilibrium and maximin are mixed and the game is 2-by-2. Maximin is proposed as an alternative solution concept in “relevant situations”. 相似文献
118.
Paul S. J. Wymenga 《Bulletin of Indonesian Economic Studies》1991,27(1):127-153
Around the mid-1980s, Indonesia's protectionist regime supported an industrial structure in which industries were mainly oriented towards producing for the domestic market. Since then, trade policies have shifted to a more outward-looking strategy, stimulating the growth and diversification of non-oil manufactured exports. This paper attempts to quantify the nominal and effective rates of protection resulting from trade policies at the end of the 1980s. After an introduction in which the 1989 trade policies are discussed, estimates of nominal and effective rates of protection are presented. It is shown that though the level of protection has declined since 1987, it still varies widely across economic sectors. Furthermore, despite the more open trade strategy, the paper's findings show that the trade regime remains biased against exports. Finally, by examining some trade policy issues, the paper presents further ways of rationalising the structure of protection in Indonesia's industrial sector. 相似文献
119.
J. A. L. Cranfield 《Revue canadienne d'agroeconomie》2003,51(3):299-321
Optimal investment rules are developed for a producer agency investing in domestic-market generic advertising, export market promotion, and cost-of-production-reducing research. These rules are derived assuming either maximization of producers' surplus or social surplus. The form of the optimality rules differs according to which objective is pursued. Fixed producer agency budgets are also allowed by incorporating a constraint limiting total expenditure on the three activities. Addition of such a constraint substantially alters the structure of the optimal investment rules. Differences in these rules highlight the importance of accounting for the financing mechanism when modeling optimal checkoff fund investment decisions. Optimality rules are simulated using data for the Canadian beef sector. Results suggest historic underinvestment in domestic-market generic advertising but overinvestment in export market promotion. Sensitivity of simulation results underscores the difficulty in assessing optimality of historic producer investment in cost-of-production-reducing research. 相似文献
120.
This paper deals with an economic comparison between costs and incomes in small wastewater treatment plants where the anaerobic co-digestion process of sludge and biowaste with energy recovery is operated. Plants in the size range 1,000-30,000 persons equivalent (pe) were considered in the study: typical costs, comprehensive of capital and operating costs, were in the range euro69-105 per person per year depending on the plant size: the smaller the size the higher the specific cost. The incomes deriving from taxes and fees for wastewater treatment are generally in the range euro36-54 per person per year and can only partially cover costs in small wastewater treatment plants. However, the co-treatment of biowaste and the use of produced energy for extra credits (green certificates) determine a clear improvement in the possible revenues from the plant. These were calculated to be euro23-25 per person per year; as a consequence the costs and incomes can be considered comparable for wastewater treatment plants (WWTPs) with size larger than 10,000 pe. Therefore, anaerobic co-digestion of biowaste and sludge can also be considered a sustainable solution for small wastewater treatment plants in rural areas where several different kinds of biowaste are available to enhance biogas production in anaerobic reactors. 相似文献