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31.
Replacement investment is essentially a regenerative optimal stopping problem; that is, the key decision concerns when to terminate the life of existing plant – and hence when to start over again. This paper examines this optimisation problem within a continuous time framework and studies the qualitative and quantitative impact of uncertainty on the timing of new investment (and the criteria that should be used for terminating the life of existing plant).  相似文献   
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In this paper the role of expenses in explaining closed-end fund discounts is re-examined. A present value model is developed to illustrate the relationship between expenses and discounts. Earlier studies find that discounts are not related to management fees. In this paper, using a larger sample over a longer and different period and a better specification of the expense variable consistent with the model developed, discounts are found to be significantly related to expenses. The relationship between expenses and discounts holds in the presence of other control variables.  相似文献   
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Young children's memory for television advertising is important in order for children to recognize brands in stores and/or to recall the brand name in making a purchase request. Two experiments showed that the use of visual advertising retrieval cue (a green frog as the brand character) improved memory performance and brand evaluations. Study 1 (n = 40) showed promise in the cue's assistance in children's recalling the brand name (cued recall) from the ad memory trace. Study 2 (n = 40) contained multiple exposures to the ad, which resulted in greater free recall and in support for the cue's assistance in better access of the brand name from the ad memory trace (cued recall). Affected ad memory resulted in more favorable brand evaluations and intent to request the brand's purchase. © 1994 John Wiley & Sons, Inc.  相似文献   
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We study the evolution of an economy where agents who are heterogeneous with respect to risk attitudes can either earn a certain income or enter a risky rent-seeking contest. We assume that agents behave rationally given their preferences, but that the population distribution of preferences evolves over time in response to material payoffs. We show that, in particular, initial distributions with full support converge to stationary states where all types are still present. Although rents are perfectly dissipated in material terms at a steady state, efficiency is greater than if everybody had been risk neutral, since risk lovers specialize in rent seeking.  相似文献   
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Reuse of wastewater is regarded as one important way to deal with the world's shortage of potable water. The authors focused on a disinfection system using micro-bubbles and evaluated its capability for wastewater reuse. This paper reports experimental results from examination of the basic characteristics of micro-bubbles and disinfection of secondary effluent by air or ozone micro-bubbles. The results suggest that when micro-bubbles are applied in an ozonation system it is possible to reduce the reactor size, the amount of ozone decomposition equipment needed and the ozone dose rate.  相似文献   
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This study investigates the hybrid mediated electrochemical oxidation (HMEO) technology, which is a newly developed non thermal electrochemical oxidation process for organic destruction. A combination of ozone and ultrasonication processes to the mediated electrochemical oxidation (MEO) process is termed as hybrid mediated electrochemical oxidation. The electrochemical cell was developed in this laboratory. In the present study, several organic compounds, such as phenol, benzoquinone and ethylenediaminetetraacetic acid (EDTA), were chosen as the model organic pollutants to be destructed by the hybrid process. The organic destruction was monitored based on the CO2 generation and total organic carbon (TOC) reduction. The HMEO process was found to be extremely effective in the destruction of all the target organics chosen in this study. The information obtained from this study will provide an insight in adopting this technique for dealing with more recalcitrant organics (POPs).  相似文献   
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