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81.
The demand for and supply of analysts’ opinions in this model yield an equilibrium that demonstrates how the information content of the opinions reacts to changes in exogenous parameters. The model also shows how changes in the parameters make analysts’ opinions more or less dispersed; for example, a decline in investor risk aversion, a decrease in market volatility, and an increase in information costs can lead to analysts’ opinions becoming more similar. Recognizing how exogenous factors can affect the supply and demand of analysts’ opinions gives additional insights into questions concerning what may appear to be herd behavior by analysts and also the relationship between forecast dispersion and information content. (JEL: G29, C71)  相似文献   
82.
Problems arising with connecting the second exhaust-heat boiler to the first exhaust-heat boiler under load in the case of flow circuits of combined-cycle plants of type PGU-450 are considered. Similar problems exist for two-boiler single-turbine units of type PGU-325 and for two-boiler single-turbine units of traditional steampower plants with an output of 200–300 MW upon connection of the second furnace of a two-furnace boiler to the operating first furnace. Analysis of the temperature-induced stressed state and of the cyclic strength of thick-walled elements of the steam-water conduit of PGU-450 and of two-furnace boilers of two-boiler single-turbine units with an output of 200–300 MW (the check valve, the inlet header of the water economizer) is used for determining the steam temperature differences in the high-pressure conduits to the steam turbine and the order of connection of the second exhaust-heat boiler to the operating fist one. Modes of enabling a two-boiler single-turbine unit of a combined-cycle plant, which are most “rigid” from the standpoint of thermal strength, are determined. __________ Translated from élektricheskie Stantsii, No. 2, February 2006, pp. 11–17.  相似文献   
83.
84.
Ohne Zusammenfassung Dipl.-Ing. (univ.) Michael Belau ist Director und Head of Rental Management Dipl.-Wirtschaftsing. (FH) Michael Schildger ist Vice President und Head of Finance Dr. Verena Sturm ist Manager Corporate Real Estate Services  相似文献   
85.
86.
The rise of environmentalism in the past decade has become a major transforming force in pollutive and hazard prone industries. Corporate environmental responsiveness is not simply a peripheral and one of the many ‘social’ or ‘ethical’ issues facing business. It is becoming a central concern for competitiveness, productivity, and profitability. It is creating strategic transformation of companies in a diverse range of industries such as, Autos, Chemicals, Oil, Fast Foods, Power Generation, Pharmaceuticals, etc. The process of environmentally directed self-renewal, called ‘greenewal’ here, affects all aspects of companies. It implies changes in products, production systems, waste management practices and internal systems. It seeks to make companies simultaneously more competitive and environmentally responsible. This paper describes the pressures of and responses to environmentalism in a selected set of industries. It examines the processes of greenewal that companies are undergoing. It identifies implications for strategic greening of firms.  相似文献   
87.
ARE EQUIVALENCE SCALES THE SAME FOR THE UNITED STATES AND CANADA?   总被引:1,自引:0,他引:1  
This research uses microdata from the 1986 Statistics Canada Family Expenditure Survey and from the 1986–88 U.S. Consumer Expenditure Survey to estimate equivalence scales using a methodology which is very similar to that employed by Statistics Canada for the estimation of Low-Income Cutoffs. Employing identical sample selection criteria and identically specified models, we find that equivalence scales for the two countries are not, in general, statistically different when estimated in the same way. The larger issue is then whether the two countries should choose the same methodology for the estimation of equivalence scales.  相似文献   
88.
This article analyses the effects of action aimed at narrowing the gap between South Africa's ‘two agricultures’, specifically the effects of the Farmer Support Programme (FSP) on structural aspects of maize production under different marketing policies. This is done by assembling a sectoral linear programming model of the South African summer-rainfall grain-producing area. The emphasis is on the inclusion of supply, demand and production risk. Results show that the effects of a successful FSP on specific interest groups, e.g. consumers of a specific product, or producers in a specific region, depend on the marketing policy followed, as well as on the effectiveness of the FSP. The analysis accentuates the interrelationships in South African crop production and illustrates how past policies ignored regional comparative advantages, distorted regional development and affected social welfare.  相似文献   
89.
The influences of the Samarra impoundment on the ecology of the downstream sector of the river Tigris are investigated. Zooplankton were collected monthly from July 1987 to July 1988. It was found that zooplankton were most abundant during high river discharges in March. During the month of low river discharge, September, the zooplankton population was greatly reduced immediately below the barrage and remained so to the last downstream station. Several factors seem to explain such differences. The high discharge from the impoundment was found to be the dominating factor and may flush the small backwaters in which zooplankton were abundant, thus increasing the population in the river. Zooplankton species vary in their ability to sustain populations in the river, variations which are due mainly to species-specific characteristics.  相似文献   
90.
Summary. This paper defines and studies optimality in a dynamic stochastic economy with finitely lived agents, and investigates the optimality properties of an equilibrium with or without sequentially complete markets. Various Pareto optimality concepts are considered, including interim and ex ante optimality. We show that, at an equilibrium with a productive asset (land) and sequentially complete markets, the intervention of a government may be justified, but only to improve risk sharing between generations. If markets are incomplete, constrained interim optimality is investigated in two-period lived OLG economies. We extend the optimality properties of an equilibrium with land and give conditions under which introducing a pay-as-you-go system at an equilibrium would not lead to any Pareto improvement. Received: October 5, 1998; revised version: April 3, 2001  相似文献   
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