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Public projects are conducted on behalf of citizens and taxpayers, who may have different views of what success looks like. The authors argue that the definition of success needs to be broad and multifaceted, even more in public than private projects. A generic six-criteria model is suggested, which covers project success on three analytical levels, from various valuation perspectives, and intended and unintended impacts alike. The model is used to evaluate 34 projects some years into their operational phases. The findings suggest that public projects are often more successful than people think. For example, cost performance is largely acceptable, contrary to the impression presented by the media and some academic studies. We also demonstrate how projects can be successful in some respects yet unsuccessful in others. We argue that the media, the most important source of information for members of the public, has a narrow definition of success and is negatively biased. It seems that ex post evaluation applying a standardized and multifaceted framework, provides a good basis for learning and improvement, to enhance the success of future projects on all levels.  相似文献   

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Urban water utilities have focused on setting water prices to cover average costs, usually using increasing block rate designs. In an attempt to contribute to the use of efficient, equitable, and revenue-sufficient pricing, this paper estimates the long-run marginal and average social costs of water supply in Mekelle city using a multi-product translog cost function that incorporates the shadow price of natural water. Findings show that the marginal social costs of providing one m3 of residential and non-residential water are Birr 5.33 and 7.71 (Birr = Ethiopian currency: 1 Euro ≈ 23 Birr), respectively, while the average current prices are Birr 4.46 and 6.10/m3. On the other hand, the average social costs of residential and non-residential water are estimated at Birr 14.34 and 16.36/m3, respectively, implying that marginal social cost-based prices would still lead to a revenue deficit of approximately Birr 9/m3.  相似文献   

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The critical role of the front–end development phase for the success of megaprojects is widely acknowledged despite a lack of theorizing and empirical evidence on what constitutes development performance and success and how to measure them. Rational–instrumental conceptualizations focus on identifying a large number of universal success factors that help avoid the pitfalls of megaproject development. However, these approaches neglect the adversarial and contingent nature of megaprojects and the complex dynamic interactions between their multiple facets. As a remedy, to define and measure the performance and success of megaproject development phase, we build a process–oriented framework which focuses on convergence in terms of project representations and stakeholders’ volition. Then, we propose clear definitions of megaproject development performance and success, by attempting to address the ambiguous distinction between the definitions of overall project success and performance, and by suggesting ways in which our results could help set on a more rigorous ground the research on the relation between development phase performance and overall project success.  相似文献   

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This paper calls into question a main assumption of governance research that the success of regional energy transitions depends to a large extent on collaborative governance structures. The role of network-based governance in two regions, Lüchow-Dannenberg and Prignitz, is analysed. Alternative ways of understanding the success of energy transitions are discussed with the help of three strands of critical governance literature: debates about ‘socio-materiality’, the often neglected role of power and key individuals. Especially power and the ‘material’ dimension of energy regions may help to explain interregional differences in the success of energy governance.  相似文献   

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Since REACh applies in all of EU, special emphasis has been put on the reduction of systematic ecotoxicity testing. In this context, it is important to extract a maximum of information from existing ecotoxicity databases in order to propose alternative methods aimed at replacing and reducing experimental testing. Consequently, we analyzed a database of new chemicals registered in France and Europe during the last twenty years reporting aquatic ecotoxicity data with respect to three trophic levels (i.e., Algae EC50 72 h, Daphnia EC50 48 h and Fish LC50 96 h). In order to ensure the relevance of the comparison between these three experimental tests, we performed a stringent data selection based on the pertinence and quality of available ecotoxicological information. At the end of this selection, less than 5% of the initial number of chemicals was retained for subsequent analysis. Such an analysis showed that fish was the least sensitive trophic level, whereas Daphnia had the highest sensitivity. Moreover, thanks to an analysis of the relative sensitivity of trophic levels, it was possible to establish that respective correction factors of 50 and 10 would be necessary if only one or two test values were available. From a physicochemical point of view, it was possible to characterize two significant correlations relating the sensitivity of the aforementioned trophic levels with the chemical structure of the retained substances. This analysis showed that algae displayed a higher sensitivity towards chemicals containing acid fragments whereas fish presented a higher sensitivity towards chemicals containing aromatic ether fragments.Overall, our work suggests that statistical analysis of historical data combined with data yielded by the REACh regulation should permit the derivation of robust safety factors, testing strategies and mathematical models. These alternative methods, in turn, could allow a replacement and reduction of ecotoxicological testing.  相似文献   

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The NRCC model of fully developed compartment fires is discussed. Although the mathematics involved is quite simple, it allows a rather comprehensive simulation of the fire process. The model offers an explanation for the findings that ventilation control is related to the pyrolysis mechanism and is not a result of scarcity of air in the fire compartment, and that thermal feedback is of secondary importance in the burning (pyrolysis) of cellulosic fuels. Another feature of the model is the introduction of the normalized heat load concept. The normalized heat load is a scalar quantity that depends on the total heat absorbed by the compartment boundaries during the fire incident, and is practically independent of the temperature history of the fire. A simple explicit formula has been proposed and proved experimentally to describe the normalized heat load for real-world fires with fair accuracy. The normalized heat load concept offers a simple means for converting fire severities into fire resistance requirements, and makes it possible to design buildings for prescribed levels of structural fire safety. The potential of fires to spread by convection and the expected characteristics of fires of noncharring plastics are also discussed. Reference: T. Z. Harmathy, Postflashover Fires—An Overview of the Research at the National Research Council of Canada (NRCC), 1970–1985,Fire Technology, Vol. 22, No. 3, August 1986, p. 210.  相似文献   

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The objective of this comment is to supplement the paper by Meikle and Connaughton, published in this journal. That paper concentrated on the non-replacement of an ageing housing stock, and the maintenance implications of the recent shift towards owner-occupation in England. The ethics behind this trend of tenure change were not questioned; an acceptance of ‘individual’ ownership and responsibility seemed apparent. The relative success of public sector housing management was not considered. This comment will aim to address this. While recent changes in housing tenure will create new problems to overcome, and will therefore need to be examined carefully, a multitude of existing problems remain. This comment will seek to illuminate one problem area: the effective management of multiple-unit housing stocks, and how this may provide a framework for the maintenance of the nation's ageing housing stock.  相似文献   

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In this paper we argue that it is necessary to apply economic impact models in smart specialization policy in order to come up with reliable economic impact estimations. Solutions suggested in the smart specialization (S3) literature for economic impact assessments cover the economic effects only partially. To estimate the impacts in the industrial, regional and national dimensions in their entirety the application of specifically designed economic models becomes necessary. We extended the geographic macro and regional (GMR)-Hungary policy impact model with additional features to make this model applicable for S3 economic impact estimations. In our policy simulations we illustrate how the application of this model helps policy-makers in the prioritization process.  相似文献   

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Bridges are taken for granted in the modern world as utilitarian structures and if noticed at all are remarked upon mainly for the elegance of their engineering structures, but a mere couple of centuries ago many in Europe still had chapels in which prayers for a safe crossing could be said. In the Dong areas of south-west China, which remained remote until around two decades ago, the bridges are the principal monuments, elaborately roofed and decorated with shrines to various gods, built with pride and at great local cost. Our research began with the question of why so much trouble was taken over these bridges, and led on to how they were read by their users and builders, and what they were considered to mean. The consequent excursions into anthropological theory and traditional Chinese ideologies, which can only be briefly summarised in the following paper, revealed a rich and complex network of causes, fascinating in their multiplicity and interaction. The enquiry was pushed far beyond the bounds of traditional art history, engaging fundamental questions about the significance of architecture as a communicative and ritual medium in traditional oral-based cultures. At a more general level it also prompted a thought-provoking exploration of the similarities and differences between bridges metaphorical and bridges physical.  相似文献   

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《Urban Water Journal》2013,10(8):812-826
ABSTRACT

This study provides an overview of the 21st century research trends for water leakage control strategies that focus on pressure management, active leakage control, pipe rehabilitation, asset management and District Metered Area (DMA) design. The biggest contribution comes from the research team in Italy, whilst the most active researcher is based in Greece. Research in this field has gained momentum from 2008 although a couple of studies have been conducted since 2000. Control strategies are receiving attention not only from academia but also from industrial players who are looking for technological advances by collaborating with academic institutions in research and development. The main strategy to reduce water leakage is the pressure management of water distribution systems using optimal settings of a pressure reducing valve installation. Despite available technologies, the commitment from the government, the water operators and the local consumers are the most important criterion for the effective implementation of water-leakage control strategies.  相似文献   

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The reversal of the migration turnaround: resumption of traditional trends?   总被引:1,自引:0,他引:1  
"Cochrane and Vining's study of recent trends in core-periphery migration, while suffering from some weaknesses in methodology and interpretation, confirms very clearly that the reversal of the metropolitan migration turnaround is a widespread phenomenon in the developed non-Communist world. Evidence from the United Kingdom also supports this observation. An examination of the possible factors responsible for the rise and fall of counterurbanization over the past two decades suggests that two major forces--population deconcentration and regional restructuring--are operating simultaneously but relatively independently and that they both fluctuate in their nature and strength over time in response to prevailing demographic and economic circumstances."  相似文献   

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