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111.
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Runoff monitoring of six rainfall events was carried out in a highway, Winterthur, Switzerland focusing on first flush (runoff volume up to 2.88 mm). Six runoff events were used to investigate the characteristics of particle-associated PAHs in first flush. The fine fraction (< 45 microm) had a relatively higher contribution than the coarse fraction. A significant contribution of the coarse fraction was observed at some periods when the runoff flow rapidly increased. Fluctuation of PAH content during a runoff event was significant in the coarse fraction and, in contrast, the PAH content in the fine fraction was less fluctuating. The weighted average PAH content in each event ranged from 17 to 62 microg/g in total SS, from 23 to 54 microg/g in the fine fraction and from 16 to 84 microg/g in the coarse fraction. The loading of particle-associated PAHs from the first flush of highway runoff ranged from 0.06 to 0.22 g/ha in a total of 12 PAH species.  相似文献   
113.
It is considered that refractory dissolved organic substances have caused an increase in the COD concentration in Lake Biwa in recent years. We investigated the organic matter in the first flush of stormwater runoff from a road in the watershed area of the lake, and studied the possibility of improvement in the water environment from that aspect. After percolating the stormwater through soil, we analyzed organic substances fractionated by using GPC-TC. And we examined the effect of removal of organic substances by comparing the peak height before and after percolation. In the result of the experiments, we found that soil infiltration reduced the refractory dissolved organic substance and we successfully designed a system for a simple and easy experimental facility to treat urban runoff.  相似文献   
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Hypotheses which relate top-level managers' age, years of company and industry service, and education to strategic change are studied with a sample of 855 managers from 27 railroads. Results generally support hypotheses that younger managers and those with less experience are more likely to alter their strategies with changing environmental conditions.  相似文献   
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This study examines effects of four combinations of accounting bases and service levels — GAAP and income tax bases, and audit and review service levels — on loan officers' decisions, both separately and in interaction. It examines effects on loan decisions and perceptions of interest rates, default risk, confidence, and usefulness. The interaction of accounting basis and service level significantly affects perceived confidence but does not affect other decisions. Accounting basis and service level separately affect interest rates, default risk, and report usefulness, but do not affect the loan decision.  相似文献   
118.
Kamstra et al. [Kamstra, M.J., Kramer, L.A., Levi, M.D., 2000. Losing sleep at the market: the daylight saving anomaly. The American Economic Review 90, 1005–1011] argue that the mean weekend return following the changes in daylight saving time is less than the mean weekend return throughout the rest of the year. Opposing studies, such as Pinegar [Pinegar, J.M., 2002. Losing sleep at the market: comment. The American Economic Review 92, 1251–1256), reason that the observed results depend upon methodology. We extend the ongoing discussions by providing further evidence for equity markets and bond markets in Germany and across Europe. We further demonstrate that the daylight saving effect does not serve as a potential rationale for the weekend effect.  相似文献   
119.
Graphical models provide a powerful and flexible approach to the analysis of complex problems in genetics. While task-specific software may be extremely efficient for any particular analysis, it is often difficult to adapt to new computational challenges. By viewing these genetic applications in a more general framework, many problems can be handled by essentially the same software. This is advantageous in an area where fast methodological development is essential. Once a method has been fully developed and tested, problem-specific software may then be required. The aim of this paper is to illustrate the potential use of a graphical model approach to genetic analyses by taking a very simple and well-understood problem by way of example.  相似文献   
120.
Given the objective of maximizing the wealth of existing shareholders, this paper discusses some of the issues that arise in attempting to measure the performance of individual businesses within a bank. The paper describes two return measures – return on assets within a business and the return on the 'equity' of an individual business – and discusses the appropriate bench–marks. The paper ends with a discussion of the cost of unused allocated capital and the appropriate performance metric.
(J.E.L.: G30, G31).  相似文献   
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