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171.
Kalustyan É. S. 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1994,28(5):258-265
Power Technology and Engineering - 相似文献
172.
Jayatilleke S. Bandara 《Journal of economic surveys》1991,5(1):3-69
Abstract. The use of CGE models has gained much popularity among policy analysts in LDCs and there is a fast growing body of literature on this area of economics. In this survey, the advantages of general equilibrium approach over partial equilibrium approach in analysing a wide range of policy issues are highlighted. The evolution of CGE modelling is discussed and more than 60 CGE applications related to different policy issues in LDCs are surveyed. This comprehensive survey shows that the CGE models have become quite popular analytical tools among policy analysts in LDCs over the last decade or so. The debate in the economic profession regarding the value and appropriateness of using CGE models for policy analysis is examined in the final section of this paper. Some of the criticisms levelled at CGE models are discussed and it is argued that despite this criticism such models are capable of providing insight into important policy problems. 相似文献
173.
While conjoint analysis has been applied in a wide variety of different contexts in Marketing, most applications fail to explicitly consider retaliatory reactions from competitors. In this paper, a methodological extension is developed for conjoint analysis by explicitly modeling competition in a game theoretic context. The Nash equilibrium concept is employed to model competitive reactions to produce design, and its implications for reactive product strategies are discussed. The optimal product design problem for each firm is formulated as a nonlinear integer programming problem, which is solved via a specialized branch and bound method combined with a heuristic. In order to compute a Nash equilibrium, a sequential iterative procedure is proposed. The proposed procedure is illustrated under several scenarios of competition using previously published conjoint data.This research has been supported by the Henry Rutgers Research Fellowship, Rutgers University. 相似文献
174.
C S van der Waal 《Development Southern Africa》1994,11(3):429-436
In One destiny: Our common future in Africa the author relates, in popular fashion, a series of incidents which convinced him that the basic difference between black and white in South Africa is cultural deep‐seated and the cause of underdevelopment and conflict He develops a circular argument in which world‐view is taken as the root of perceptions, values and activities. The effects of experience and economic and political factors are given secondary importance. This argument cannot accommodate social change and differentiation, and the author tends to concentrate on perceptions and events which he finds morally unacceptable. He gives an unbalanced assessment and an ethnocentric interpretation of African life. Possible reasons for this type of argument are explored and an alternative which takes its departure from the interaction between experience and perception is offered 相似文献
175.
176.
Five years after the introduction of unified monetary policy in the EMU, some member countries are wondering whether they have ceded too much of their policy-making powers. The fact that National Central Banks no longer carry out sizable expansionary open market or foreign exchange market operations suggests that they face substantially reduced abilities to set economic policy.This paper demonstrates that, in fact, very little power has been yielded: on the fiscal front, the force of such policy initiatives is enhanced by the fixity of the exchange rate. On the monetary front, we show that there is an observational equivalence between all Central Bank actions under fixed exchange rates. This implies that the authorities retain the same amount of policy flexibility as before. So long as they use an alternative form of policy initiative, carrying out what previously would have been characterized as sterilized foreign exchange market operations, their ability to influence the macro performance of their economy is undiminished. 相似文献
177.
The solar photocatalytic degradation of methyl parathion was investigated using a circulating TiO2/solar light reactor. Under solar photocatalysis condition, parathion was more effectively degraded than solar photolysis and TiO2-only conditions. With solar photocatalysis, 20 mg/L of parathion was completely degraded within 60 min with a TOC decrease of 63% after 150 min. The main ionic byproducts during photocatalysis recovered from parathion degradation were mainly as NO3-, NO2- and NH4+, 80% of the sulphur as SO4(2-), and 5% of phosphorus as PO4(3-). The organic intermediates 4-nitrophenol and methyl paraoxon were also identified, and these were further degraded in solar photocatalytic condition. Two different bioassays (Vibrio fischeri and Daphnia magna) were used to test the acute toxicity of solutions treated by solar photocatalysis and photolysis. The Microtox test using V. fischeri showed that the toxicity expressed as EC50 (%) value increased from 5.5% to >82% in solar photocatalysis, indicating that the treated solution is non-toxic, but only increased from 4.9 to 20.5% after 150 min in solar photolysis. The acute toxicity test using D. magna showed that EC50 (%) increased from 0.05 to 1.08% under solar photocatalysis, but only increased to 0.12% after 150 min with solar photolysis, indicating the solution is still toxic. The pattern of toxicity reduction parallels the decrease in TOC and the parathion concentrations. 相似文献
178.
V. S. Kucheryavyi 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1985,19(9):463-466
Conclusions After the almost 2-yr operation of the gate apparatus since the start of reconstruction of friction units of the vanes, we can make a preliminary evaluation of the effectiveness of the works:There is practically no leakage of water through the gate vanes to the turbine cover, which led to a complete unloading of the drainage pumps on the turbine cover and the efficiency of operating the gate apparatus increased considerably.Repair of the gate apparatus is not required during maintenance.There is no vibration of the gate vanes, since the gaps in the friction units of the journals of the gate vanes are minimum and stable.The operating personnel objectively evaluate highly the work of the gate apparatus of the turbine after reconstruction and will continue this work on the remaining turbines.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 12–14, September, 1985. 相似文献
179.
I. S. Sheinin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(10):609-615
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 1–6, October, 1992. 相似文献
180.
I. S. Sheinin I. S. Kal'tseva 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(3):168-175
Translated from Gidrotehnicheskoe Stroitel'stvo, No. 3, pp. 27–31, March, 1992. 相似文献