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101.
Ya. V. Maksimenko V. S. Nesterenko 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1989,23(11):617-620
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 6–7, November, 1989. 相似文献
102.
An innovative method for modelling biological processes under anaerobic conditions is presented and discussed. The method is based on titrimetric and off-gas measurements. Titrimetric data is recorded as the addition rate of hydroxyl ions or protons that is required to maintain pH in a bioreactor at a constant level. An off-gas analysis arrangement measures, among other things, the transfer rate of carbon dioxide. The integration of these signals results in a continuous signal which is solely related to the biological reactions. When coupled with a mathematical model of the biological reactions, the signal allows a detailed characterisation of these reactions, which would otherwise be difficult to achieve. Two applications of the method to the enhanced biological phosphorus removal processes are presented and discussed to demonstrate the principle and effectiveness of the method. 相似文献
103.
General relationships between organisms and their habitat, consistent across spatial scales and regions, suggest the existence of repeatable ecological processes and are useful for the management of stream networks. From published data, we defined four guilds of European fish species with contrasting preferences for microhabitat hydraulics within stream reaches. At the scale of stream reaches and across 139 French sites (590 460 fishes sampled), we analysed how fish guild proportions were related to reach hydraulics (proportion of pools vs. riffles %POOL; median discharge by unit width Q50/W). The strongest correlations were observed between two fish guilds and %POOL (p < 0.001, r2 ≥ 0.41) and between one fish guild proportion and Q50/W (p < 0.001, r2 = 0.10). These reach–scale relationships were consistent across six large French basins, and consistent with the analyses made at the microhabitat scale. Therefore, microhabitat preferences for hydraulics are strong enough to generate consistent reach‐scale community responses to hydraulics across regions, despite the influence of other filters such as temperature, nutrient levels or history. The distribution of basic geomorphic features (pools, riffles) in streams and their modification (by dams, weirs and dikes) can modify the proportion of fish guilds by up to 80%, probably contributing to the long‐term decline of riffle‐dwelling species in Europe. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
104.
Steven N. S. Cheung 《Economic Affairs》1986,6(5):26-29
The speed with which communist China has embuaced markets has surprised Western analysis and observers, But Chinese economic progress will founder in corruption and inefficiency, argues Professor Steven Cheung of the university of Hong Kong, untess she insitutes a well-defined system of private property rights to safeguord investment and stimulate trade. 相似文献
105.
S K Smith 《Journal of economic and social measurement》1986,14(1):37-49
As the elderly population of the United States grows in absolute number and as a proportion of total population, accurate projections of that population become increasingly important for sound policy decisions. Cohort component techniques are typically used for state and local projections of the elderly population, but are often outdated or even nonexistent for many local areas. This paper suggests an alternative approach, based on Medicare data and simple projection techniques. Projections for several base periods and projection horizons are made for all states and for counties in Florida and are compared with actual Medicare enrollment. On the basis of these comparisons it appears that Medicare data and simple projection techniques can produce very useful short-run projections of the elderly population for states and local areas. 相似文献
106.
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108.
Numerous labor-management issues possess ethical dimensions and pose ethical questions. In this article, the authors discuss four labor-management issues that present important contemporary problems: union organizing, labor-management negotiations, employee involvement programs, and union obligations of fair representation. In the authors view, labor and management too often view their ethical obligations as beginning and ending at the law's boundaries. Contemporary business realities suggest that cooperative and enlightened modes of interaction between labor and management seem appropriate.Robert S. Adler is Associate Professor of Legal Studies at the Kenan-Flagler Business School, University of North Carolina at Chapel Hill. He teaches courses in Business Law, Business Ethics, and Regulation. Prior to coming to UNC, Professor Adler served as Counsel to the Subcommittee on Health and the Environment of the Committee on Energy and Commerce of the U.S. House of Representatives.William J. Bigoness is Professor of Business Administration and Director, Center for Management Studies at the Kenan-Flagler Business School, University of North Carolina at Chapel Hill. His professional interests include organizational behavior, human resource management, and labor-management relations. Dr. Bigoness was Visiting Professor of Business Administration at the International Institute for Management Development (IMD) located in Lausanne, Switzerland from 1985 to 1987. 相似文献
109.
This paper makes a preliminary assessment of how the current structure for the distribution of UK National Lottery funds affects the promise of net additionality for the designated 'good causes'. Indifference analysis demonstrates that the funding structure is optimal in these terms. However, the measurement of net additionality is highly problematic and involves both quantitative and qualitative techniques. Whilst a preliminary comparison with Ireland shows that the UK system is in a better position to achieve net additionality through its accountability and transparency, net additionality could still be only a relatively small proportion of the dedicated Lottery money, depending on the behaviour of politicians, local authorities, other interest groups, and the distribution boards themselves. 相似文献
110.
We provide a framework in which we link the valuation and assetallocation policies of defined benefits plans with the lifetimemarginal productivity schedule of the worker and the pensionplan formula. In turn, we examine the retirement policies thatare implied by the primitives of the model and the value ofpension obligations. Our model provides an explicit valuationformula for a stylized defined benefits plan. The optimal assetallocation policies consist of the replicating portfolio independentof the pension liabilities. We show that the worker with retirewhen the ratio of pension benefits to current wages reachesa critical value which depends on the parameters of the pensionplan and the discount rate. Using numerical techniques we analyzethe feedback effect of retirement policies on the valuationof plans and on the asset allocation decisions. 相似文献