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41.
New business formation is a formidable and daunting task, which may require personal perseverance and self‐efficacy. If this is indeed the case, will entrepreneurs and non‐entrepreneurs differ on such attributes? Also, if high levels of perseverance and self‐efficacy help entrepreneurs to overcome setbacks, snags, and obstacles, do these positive attributes co‐occur with significant personal costs, such as the tendency to experience regretful thinking? This study uses a random sample of 217 patent inventors in the medical industry (surgery devices) to address these questions. Results indicate that entrepreneurs score significantly higher on self‐efficacy and on two distinct aspects of perseverance—perceived control over adversity and perceived responsibility regarding outcome of adversity—than did non‐entrepreneurs. Also, although entrepreneurs report the same number of regrets, their regrets are stronger and are qualitatively different from those reported by non‐entrepreneurs. These findings suggest that perseverance and self‐efficacy do indeed co‐occur with regretful thinking. Finally, post hoc analysis reveals that the higher the overall perseverance scores of patent inventors, the higher their annual earnings. We conclude by examining the implications for theory, researcher, and practice. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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This study estimates the economic value of externalities related to waste transfer stations in Israel. Most externalities are associated with local disamenities experienced by residents living in close proximity to transfer stations - including noise, odor, litter, vermin, visual intrusion and any associated perceived discomfort. Following the mapping of all active transfer stations in Israel, problematic sites near residential areas were identified. Four of these sites were selected for detailed examination. The study involved estimating the economic value of disamenities using the Hedonic Price Method, which examines the impact of disamenities on property values. The results indicate that the maximum spatial extent of the impact occurs about 2.8km away from a transfer station with an increase of about $5000 in housing price for each additionalkm away from the site. Alternatively, an increase of 1% in the average distance of a house from the local transfer station is associated with a 0.06% rise in the price of the average house. These figures, representing the relationship between changes in environmental quality and property prices, indicate that transfer stations create externalities that should be taken into account in location and clean-up policies for transfer stations as well as in potential compensation policies.  相似文献   
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The aim of this study was to evaluate the importance of biotransformation of paralytic shellfish toxins during the detoxification process in contaminated oysters. Mathematical models based upon the detoxification patterns of digestive gland and other tissues were developed. It was demonstrated that biotransformations do not seem to play an important role in digestive gland or other tissue detoxification kinetics with our data set. Moreover, different toxin transfers from digestive gland toward other tissues were investigated. No significant transfer was highlighted in our data set. These first conclusions were drawn after comparing the results obtained from 13 biotransformations and identifiable transfer scenarios. Finally, to determine a more robust model, all 12 states corresponding to toxic compounds and tissues were aggregated into a single state model. The best adjustment was obtained with a simple one-compartment model based on total flesh toxicity with elimination rate expressed by a function depending on initial concentrations of GTX3 and GTX2 (i.e. the two major toxic compounds found in contaminated oysters).  相似文献   
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The purpose of this paper is twofold. First, we raise some issues related to the expected dimension of the carbon market. This analysis is based on a survey of model results on the implementation of the Kyoto goal with and without reliance on emissions trading. In particular, we consider both the emissions and the financial implications associated with different trading scenarios. Transfers related to international GHG trading might be equivalent to a 400% increase in foreign direct investment to countries with economies in transition. A closer look at the GHG reductions expected from the developing world also suggests that global models may be overly optimistic in their assessment of the contribution of flexibility mechanisms in meeting the Kyoto emission goals. OECD countries may need to rely more on domestic policies to reduce their emissions than what has so far been projected by global models. Second, we use a simple microeconomic model to test the potential contribution of typical power generation technologies in the context of the Clean Development Mechanism. Projects that are defined as additional in terms of the environment but already profitable can bring about significant results at a relatively low price of certified emission reductions. To assume that the contribution of the CDM will come close to what is projected by global models (both for prices and quantities) is to assume that such projects could be credited under the CDM. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The analysis of the variability of vehicle trajectories can reveal important information about how situational constraints influence drivers’ behaviour (e.g., lateral position and/or speed). Variability in the lateral position using a driving simulator was examined. Forty-two participants had to drive on two road environments: a 3 km straight road with a crest vertical curve (CVC) with perceptual treatments and narrowed lane width with subsequent provision of a hard shoulder, by relocation of the road markings. The results showed that, on the one hand the lateral position variability was greater when driving on the test CVC, before meeting oncoming vehicle and on the narrowed lane width; and on the other hand it was limited according to the perceptual treatment used. The lateral position variability would be a difficulty indicator of road geometry which would inform road managers of the presence of a risk zone on their road network.  相似文献   
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An integrated approach based on multiple indicators and individual and combinational evaluation methods is proposed to evaluate water scarcity. Four evaluation methods are employed, and their results are joined through three combination methods in order to obtain a consistent evaluation. This iterative-correction approach has been applied to Yunnan Province in China for water scarcity evaluation. The results demonstrate the capability of the iterative-correction framework to provide insightful analyses of water scarcity. Diqing Tibetan Autonomous Prefecture (Diqing) and Nujiang Li Autonomous Prefecture (Nujiang) ranked 1st and 2nd, indicating the best situation for water scarcity evaluation, while Yuxi and Zhaotong ranked 15th and 16th, indicating the worst situation. Two types of major water scarcities were observed in Yunnan Province. One was a typical representative of lack of water quality in the central part of Yunnan, and the other was a typical engineering type in the western part of Yunnan. The water scarcity has been found to arise from non-judicious water use, rapid urbanization and lack of protective measures for water resources. Therefore, it is necessary to conduct more water conservancy projects in future to alleviate the water scarcity issue.  相似文献   
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In order to better manage artisanal and small-scale gold mining, the Burkinabe authorities have planned to build a suitable methodological support as an aid to elaborating appropriate policies and actions. The developed methodology concerns (a) at a spatial level, the generation and analysis of a geological resources map needed by the artisanal miners and (b) at a socioeconomic level, analysis of the miners' activity. This paper reports and discusses the results of our suggestion to also introduce the use of an approach known as multi-agent system (MAS) as a complementary part of this initial methodology, at a downstage level to the above two analysis stages. MAS methodology could be used to develop simulation models to forecast the future of the activity. MAS is appropriate for describing the dynamics of systems where it is impossible to obtain all output data of a model from a purely mathematical or statistical transformation of input data. Our suggestion involves (i) demonstrating the capacity of the approach to simulate all parameters needed by mining policy makers and (ii) evaluating to what extent the methodology is accepted by them, as well as, at a more scientific level, the literature regarding mining system simulation.  相似文献   
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