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991.
Kunhee Choi Eul‐Bum Lee C. William Ibbs Yong–Woo Kim 《Construction Management & Economics》2013,31(8):771-782
A heavily trafficked 4.5km highway stretch on Interstate 15 east of Los Angeles was rebuilt using two extended closures, each spanning nine days with 24/7 operations. Before and during the closures, a multifaceted, extensive, dynamic public outreach programme was implemented to gain public support for the project and to minimize inconvenience to the public. That outreach programme is described, its overall effectiveness in terms of total net benefit and traffic inconvenience during lane closures is assessed, and changes in public perception of the accelerated construction strategy resulting from the outreach programme is examined. Pre‐ and post‐construction surveys performed using the project website mirrored the findings of the traffic measurement study, indicating that the outreach programme effectively reduced traffic demand. The results of two web‐based surveys with a combined total of approximately 400 respondents indicated a dramatic change in public perception of the accelerated construction strategy. The survey results showed that strong initial objection to the accelerated project eventually became supportive of future, accelerated projects. The cost–benefit analysis showed that the additional cost of the outreach programme was outweighed by the savings achieved from reduced road user delay costs. 相似文献
992.
The introduction of a non private‐funded public–private partnerships (PPP) approach to the maintenance and operation of infrastructure facilities necessitates an equitable performance standard, a sensible penalty mechanism and a credible auditing system. Yet, with limited research on this type of scheme, it is not clear whether the payment and audit mechanisms can adequately gauge the performance of private partners and truly reflect the quality of service provided in their payment. The question is whether the reliability of the payment reduction and auditing mechanisms pertinent to the non‐private funded PPP infrastructure maintenance can be systematically verified. With reference to a case study in Hong Kong, field data have been collected and tested according to the sensitivity analysis and level of confidence. The results indicate that the level of payment reduction due to poor performance is fair and the audit frequency is adequate to reflect the overall performance of the service provider. The approaches adopted in this research should provide an objective basis for public and private partners to formulate a mutually acceptable and effective mechanism for non private‐funded PPP infrastructure maintenance contracts. 相似文献
993.
This paper analysed 11 years of daily mean wind-speed data, measured at Akure, Ondo State, Nigeria, using Weibull and Rayleigh distribution functions. While both distributions showed good agreements in extreme-value estimation patterns, investigation of their wind-speed characteristics modelling criteria, using goodness-of-fit statistics, revealed that the wind data followed the Weibull more than Rayleigh. Monthly wind-speed of Akure city ranged from 1.41 to 4.24 m/s by the Weibull fittings and from 1.40 to 4.16 m/s by the Rayleigh fittings. Overall results, of 2.71 m/s (Weibull) or 2.70 m/s (Rayleigh) mean wind-speed and 18.51 W/m2 (Weibull) or 22.26 W/m2 (Rayleigh) mean power density, indicated Akure a low wind-speed site, requiring low wind-speed turbine for generating wind energy. Econometric analyses of power output simulations using such turbine system resulted in affordable wind energy cost. These bear policy implications for sustainable wind energy usage in this and similar regions of the world. 相似文献
994.
The transitional areas that lie between wildlands and urbanized spaces, generally defined as wildland–urban interfaces (WUI), represent an increasing risk factor in Mediterranean areas; these define a new scenario in forest fire fighting and prevention. We have developed a methodological approach in order to assess the hazard and vulnerability of WUI which is based on landscape analysis, on the use of Geographic Information Systems (GIS) techniques and remote sensing. Unlike traditional approaches which are based on local scale characterization of WUI, we propose a progressive multi-scale approach. In order to reach an operative classification of the WUI the methodology was developed in three stages: a regional urban development model, a landscape character assessment and finally, a WUI typology. The last WUI typology has been based on the identification of different urban morphologies and their context within the type of landscape in which they occur. 相似文献
995.
Selin Gundes 《Construction Management & Economics》2013,31(1):59-68
Construction is commonly regarded as an important industry in economic policy making owing to its strong interactions with other sectors in the economy. Using six national input–output (IO) tables compiled to date and economic data for the period between 1969 and 2006, the behaviour of the Turkish construction sector and its relationships to investment, income and to other sectors in the economy are examined. Analysis reveals that the construction industry is losing its propulsive role and that it tends to exaggerate the fluctuations of the economy. The examination of lead and lag times between changes in GNP, construction activity and investments show that public sector spending cuts, in particular, have significant effects on the amplitude and the timing of slumps of the industry. The analysis of linkage indicators indicates that for the whole period under consideration the construction industry has high linkages with only one other industry. Thus the ‘leading’ role it plays in the economy is questioned. 相似文献
996.
ABSTRACTThis paper explores the case of the historic harbour area of Naples, considered highly significant, due to its physical and cultural characteristics, with the aim of reflecting on the contemporary need for building renewed and synergic city–port relations in a sustainable perspective. Focusing on the physical and functional city–port integration, the study investigates Naples harbour planning policy between twentieth and twenty-first centuries in order to identify the limitations of older instruments and to exam the current proposal, finally suggesting perspectives for the future. The analysis highlights the fact that, in the port of Naples, with a landlord governance, the main obstacles to a more inclusive planning policy have been related to land use conflict between on one hand the public interest of the Port Authority and Municipality and the private interest of port operators on the other. In conclusion, the need for city–port plan integration is outlined as a central planning issue so as to combine the economic development of the harbour with social, cultural and ecological themes and to overcome the conflicts between the different actors involved in the complex planning process. 相似文献
997.
分析民用10 kV 变配电系统中的过电压保护,对无间隙氧化锌避雷器的保护原理、设置原则、参数选择进行阐述。以10 kV 小电阻接地系统与经消弧线圈接地系统的避雷器选择为例,阐述避雷器参数的选型。 相似文献
998.
《CoDesign》2013,9(2):96-111
Co-creation as a concept has won terrain over the past 10 years. In practice as well as in literature, co-creation is climbing the agenda in relation to contemporary opportunities and challenges within management, organisation design and change initiatives. This paper aims to build an overview of the literature on co-creation to explore what the existing literature relates to and indeed to pinpoint if any patterns or streams can be identified. The paper illustrates how the use of the concept of co-creation suggests a necessity for focusing further on specific co-creation-related issues and challenges of significance to business and society. The paper highlights new co-creation-related issues and challenges. Further, the paper crystallises an emerging design trajectory in theory and practice. 相似文献
999.
《Urban Water Journal》2013,10(1):33-37
The removal of heavy metals from storm and surface waters by slow sand filtration is described. The importance of speciation as a technique for exploring and improving the mechanisms of removal is identified. Laboratory-scale slow sand filters operating at conventional flow rate and depth were shown to be able to reduce concentrations of selected heavy metals (Cu, Cr, Pb and Cd) found in road runoff, surface water and sewage effluents to drinking water standard. Nitrogen, volatile solids and modified Stover speciation were used to differentiate between the potential mechanisms of removal, i.e. active biomass, organic adsorption and simple adsorption or precipitation on the surface of the sand. The data presented show that adsorption via organic ligands was the predominant mechanism for metal removal at the surface of the filter but chemical adsorption was the more important deeper in the filter. In the lower layers the adsorbed metals were more easily exchanged than the organically bound metals. The precise chemical ligands were not identified and varied from metal to metal. The most important operational factors affecting performance were therefore the concentration of organic matter, filter depth and the flow velocity. 相似文献
1000.
《Structure and Infrastructure Engineering》2013,9(2):153-156
In 1998, the Texas Department of Transportation (TxDOT) identified two concrete distress mechanisms occurring on its bridge over Lake Ivie in the west central part of the state: alkali – silica reaction (ASR) and delayed ettringite formation (DEF), collectively referred to by TxDOT as premature concrete deterioration (PCD). The agency sponsored two research projects to investigate the problem. One focused on determining the remaining capacity of PCD-damaged concrete members with a case study of the Lake Ivie bridge and the other assessed treatments that could be applied to members with PCD damage. Based on findings of the study, TxDOT applied a system that waterproofed the damaged columns and then confined them using resin-bonded carbon fibre reinforced polymer (CFRP) fabric strips. This paper describes the efforts of TxDOT to mitigate PCD damage for its Lake Ivie bridge. 相似文献