共查询到20条相似文献,搜索用时 15 毫秒
1.
《Urban Water Journal》2013,10(7):626-635
ABSTRACTInterest in evaluating productivity changes in water companies has increased in recent years. In this paper, for the first time, we employ the Luenberger-Hicks-Moorsteen Productivity Indicator (LHMPI) to evaluate productivity changes in a sample of Chilean water companies from 2010 to 2016. Productivity change estimations obtained by both the Luenberger Productivity Indicator (LPI) and the LHMPI are compared. Moreover, both indicators were computed assuming constant and variable returns to scale technologies. The LHMPI estimates illustrate that productivity in Chilean water companies has slightly improved over the period studied due to the positive trend of outputs, whereas the inputs negatively contributed to productivity changes. Results from the empirical analysis enabled us to verify that the LHMPI and LPI (and their drivers) are statistically different. This conclusion illustrates that water regulators need to pay attention to the indicators used when assessing productivity changes in water companies. 相似文献
2.
UK water debt has increased rapidly and has become a significant management issue for most water companies, constraining investment in necessary environmental interventions. Debt is characterised as debt penetration (percentage of customers in debt) and debt intensity (average size of debt per indebted customer). Actual debt characteristics in a water company can be plotted by intensity and penetration to demonstrate performance differences between companies, changes over time and performance relative to national norms. Using the relationships between debt and deprivation, the expected debt performance can be plotted. Using the expected position as a benchmark, the company performance can be evaluated and the remedial strategies can be targeted (if required) towards reduction of frequency and size of debt. The distance between actual and expected values is used as a metric of the requirement for additional debt management investment. Examples of these debtor plots for a range of anonymous companies are presented. 相似文献
3.
Sustainability involves focusing on a project’s impact in three areas: (1) environmental; (2) economical; and (3) societal. In reality, companies’ approaches in the three areas are not evenly distributed. A study of current trends in the US construction industry related to the emerging focus on sustainable construction will be of great value for the engineering and construction industry to recognize the differences in corporate approaches to sustainability, for the sake of team alignment. A random cross‐section of 300 companies, consisting of 150 owner companies, 75 contractor companies and 75 design firms representing a variety of industries, was selected from annual company data assembled by the weekly construction news publication Engineering News Record (ENR). To identify sustainability‐related concepts within the context of these company documents, content analyses and chi‐square statistical analyses were performed on the selected companies’ publicly available annual reports and mission/vision/values statements. The primary objectives are to: (1) identify concepts of sustainability that are currently being emphasized within the US engineering and construction industry, possibly at the expense of other concepts; and (2) develop an understanding of the relationships between various company and industry groups related to the fundamental concepts of sustainable construction. 相似文献
4.
《Urban Water Journal》2013,10(7):682-691
ABSTRACTImproving the cost efficiency and quality of service across time corresponds to two important targets for regulated water companies. Following a pioneering approach, we have evaluated the influence of a set of exogenous and quality of service variables on the English and Welsh water companies’ costs over the period of 1996–2009. A true-fixed effects stochastic cost frontier model was applied since it also allowed computing of the productivity change of the water companies and their drivers. Results have shown that quality of service has an influence on water companies´ costs. This issue is very relevant for bursts in water mains since investments in reducing them will lead to a reduction in the water supply interruptions and water losses. Results of this study illustrate the importance of developing long-term planning investment programmes in the water industry. 相似文献
5.
《Urban Water Journal》2013,10(6):518-525
AbstractThe service provision of drinking water and the disposal of waste water are severely challenged by changing framework conditions. Although service providers necessitate systematic information regarding sustainability risks, no available management tool accounts for them comprehensively. In the context of the project NaCoSi ‘Ensuring Sustainability for Urban Water Systems’, a risk-based sustainability management system (RSS) was developed. This paper aims to introduce RSS and to discuss its contribution towards companies’ viability and transformation in the water sector. The paper describes the comprehensive self-screening approach of RSS, which is based on a causal-chain concept and comprises steps of risk analysis, monitoring and mitigation. Results of the testing phase suggest the validity of risk analysis and its effectiveness in deriving measures. Thus, RSS can help to improve the ability of service providers by analysing challenges and communicating them. 相似文献
6.
Lu Liao Mildred E. Warner George C. Homsy 《Journal of the American Planning Association. American Planning Association》2020,86(1):60-74
AbstractProblem, research strategy, and findings: Plans often sit on the shelf and fail to promote action. This raises the question of how and when plans matter. This is especially important in sustainability planning where local governments are more likely to take actions with short-term benefits that are easy to adopt. How can planners promote more sustainability actions, especially those with longer term benefits? In this study we examine factors influencing local sustainability actions by tracking 651?U.S. local governments’ adoption of 34 sustainability actions from 2010 to 2015. We differentiate places that recently adopted a sustainability plan from those that have had a plan for a longer period and those that have never adopted a sustainability plan. We use difference-in-difference (DID) modeling to assess what effect plans have on the level of sustainability actions. We find a plan may have its greatest effect in motivating actions when it is newly created. Places that adopted a plan between 2010 and 2015 exhibited a significant increase in sustainability actions during those same years. By contrast, places that already had a plan in 2010 showed higher initial levels of sustainability actions but did not show a higher level of growth in the number of actions adopted compared with places without plans. In general, we find local governments with higher levels of sustainability actions articulate social equity goals, devote staff and budget resources to the effort, engage the public, and promote interdepartmental coordination. Local governments under Republican control enact fewer sustainability actions.Takeaway for practice: Sustainability plans are most effective in spurring local sustainability actions when they are newly created. However, this initiation impact in motivating actions wanes over time. Promoting continued adoption of sustainability actions requires a comprehensive approach with attention to political support, public participation, social equity, interdepartmental coordination, and local capacity. 相似文献
7.
Sustainable development principles have been implemented in various sectors including the construction industry since it was published in the Brundtland Commission Report in 1987. In line with this development, implementation of infrastructure construction projects has been given particular attention as they have more significant impacts on the environment, society and economy. It is considered that proper development and operation of infrastructure projects such as highways can contribute significantly to the mission of sustainable development. However, there is little existing work to provide appropriate methods to assess the sustainability performance of infrastructure projects. The study described in this paper introduces a simulation model, using system dynamics principle, to evaluate the sustainability performance of highway infrastructure projects during the construction and operation stage. The study introduces the indicators which measure the sustainability performance of highway projects and identifies the dynamic factors affecting indicator performance by referring to the relevant feasibility studies of highway projects. A real highway project is presented to demonstrate the application of the simulation model in evaluating the sustainability performance of the project. The case study is used to explore the solutions for improving those poor sustainability performance areas through policy scenarios. 相似文献
8.
Accurate pollutant mass budgets are needed for identifying contaminant sources and establishing cleanup goals. We monitored mercury discharges from an abandoned mine site in northern California with the objectives of: (1) estimating the mass loading of mercury from the site; (2) evaluating the factors that control the mercury discharges; (3) assessing the significance of peak flows in transporting contaminants; and (4) developing methods for measuring the effectiveness of cleanup efforts. We sampled water downstream from the mine site over a wide range of streamflows. Mercury concentrations varied over 2000-fold, from 485 to 1 040 000 ng/l, grossly exceeding the regulatory water quality objective of 12 ng/l at all times. Particulate mercury represented over 99.97% of the total mercury, and mercury concentrations were closely correlated to suspended sediment concentrations (r=0.98). Thus, we can use suspended sediment concentrations as a proxy for mercury concentrations, and calculate a continuous record of mercury flux from continuous monitoring of streamflow (using a small flume) and turbidity (using an optical backscatter sensor). Mercury fluxes inferred in this way are consistent with fluxes estimated from field samples. In January and February of 1998, our small abandoned mine site released approximately 82 kg of mercury to downstream waters. Most of the mercury was released during brief intense rainstorms. For example, in one 200-min period we recorded 3.4 cm of rain, a 2.6-fold increase in streamflow (460–1120 l/s), and an 82-fold increase in mercury flux (1.2–99 g/min). Over 75% of the total mercury flux during this 2-month period occurred in less than 10% of the total time. In systems such as this one, where contaminant transport is highly episodic, sampling programs that miss the high-flow episodes may greatly underestimate the actual water quality threat. In addition, changes in pollutant fluxes or concentrations in receiving waters may not reflect changes in pollutant sources (such as an environmental cleanup) if the stochastic forcing (e.g. intense rainstorms) varies through time. We propose that water quality trends can be more accurately measured by changes in the relationship between contaminant flux and stochastic driving factors, as expressed by contaminant rating curves. 相似文献
9.
Profitability and productivity change over time are two key indicators to evaluate the performance of water companies. In this study, the profit inefficiency of water utilities was estimated based on the Luenberger Productivity Indicator (LPI). The empirical approach focused on the English and Welsh water industry from 2001 to 2018. It was illustrated that water companies suffered a profit inefficiency effect of 50%, mainly (44%) attributed to allocation inefficiency, whereas technical inefficiency contributed by 6%. Estimated profit LPI values revealed the impact of the price reviews on the profit productivity of the English and Welsh water companies. 相似文献
10.
《Utilities Policy》2007,15(2):64-77
International actors and factors, including multinational companies, have constrained and influenced local decision-making on the structure of water systems in Europe since 1990. The EU itself has exercised a major influence through environmental directives, fiscal policies associated with economic and monetary union, and internal market policies. International financial institutions have also influenced developments, especially in central and eastern Europe, through policies and conditionalities linked to loans. The multinational water companies adopted policies of expansion in selected cities throughout Europe, achieving the privatisation of water services which had previously been directly provided by public authorities. This behaviour is subject to analysis in terms of the political economy of multinational company strategies, including the relationships between these strategies and political structures and developments. The multinational companies have been the most significant international actors, but their impact has been largely through political strategies rather than through competition with rival local companies. 相似文献
11.
工程建筑公司项目群管理:一个实施模型 总被引:1,自引:0,他引:1
对于以项目为基础的工程建筑公司而言,项目管理能力是其核心竞争力的体现.传统的项目管理过于关注单个项目的绩效,没有从企业组织的角度整体考虑,特别是在多项目环境下,往往会造成企业资源紧缺.在分析项目群管理概念的基础上,结合工程建筑公司特点,提出了项目群管理模式的实施模型,其实施过程包含目标合同的选择、项目群方案的确立、项目群实施过程控制、项目群管理绩效四个方面,并对各个方面的影响因素进行了详细的论述.旨在为工程建筑公司实施多项目管理提供一个"行动路线图",以重新审视、改进其当前的管理模式和技术,提高企业的市场竞争力和组织项目管理能力. 相似文献
12.
Annie R. Pearce Stephanie A. Smith Maria Saxton Angie De Soto 《International Journal of Construction Education and Research》2018,14(1):59-73
ABSTRACTToday’s college graduates seek employment that contributes to sustainability, while employers seek new employees who have practical, hands-on experience addressing sustainability challenges. However, few students emerge from university with the mindset and tools to immediately apply sustainability concepts to the challenges they face. A multidisciplinary, immersive, co-curricular “boot camp” sustainability learning experience can address these challenges. This article describes the design and pilot testing of a sustainability boot camp at Virginia Tech involving a team of nine interdisciplinary faculty fellows from 6 colleges and insight from over 200 sustainability experts from multiple domains. Learning outcomes were developed based on thematic analysis of industry interviews from multiple sectors, yielding a set of competencies that companies seek in new hires for sustainability positions. The program is structured around three elements (sustainability integration, professional development, and network building) and incorporates lectures, professional development training, networking opportunities, and problem-based learning to help students develop a “sustainability lens” that can be applied to not only future professional activities but also personal decisions. The first two offerings of the boot camp with 60 students provided lessons learned for others developing similar programs. 相似文献
13.
《Urban Water Journal》2013,10(5):334-342
ABSTRACTThis study applies an integrated approach to investigate public perception of residential water issues during a period of economic crisis. The study investigates the perceptions and practices of Athenians in water conservation, their satisfaction with the supplied water, their opinion on the privatization of Water Company and their willingness for additional payment for the improvement of water services. A survey was conducted using a structured questionnaire. Results indicate that the respondents have adopted water conservation practices, but there is still room for further saving. Most of the respondents declared to be satisfied with the supplied water and do not agree to the privatization of water companies. Women, older participants and those having lower income are less willing for additional payment. Research findings are useful tool for policymakers to design policies and make decisions regarding water management, ownership of water companies and changes in behavior of water use. 相似文献
14.
Thomas L. Daniels 《Journal of the American Planning Association. American Planning Association》2013,79(2):178-192
Problem: It would be useful to identify and connect the major ideas of American environmental planning from the late 19th century up to today, to show its evolution over time and anticipate its potential future direction. Purpose: I aim to tie together the major ideas of American environmental planning, showing how they have evolved, and suggest what additional changes will be required to progress further toward sustainability. Methods: I review the literature, defining five time periods that are useful for understanding and analyzing environmental planning successes and shortcomings. Results and conclusions: Environmental planning has its roots in the physical design of cities and the tension between conserving natural resources for human use and protecting wilderness. In the 1920s, regional environmental planning emerged. Federal environmental impact statements were first required in the 1970s, along with efforts to clean up and prevent pollution. A backlash against government command and control began in the 1980s, leading governments to use incentives to address environmental problems. The current era makes sustainability the goal, tying together the ideas and practices of the previous eras and blending regulation and financial incentives to address national and global environmental problems, such as climate change. To reduce carbon footprints and increase water and energy conservation in the face of significant population growth in the United States will require making environmental planning a political priority, with the goals of curbing sprawling land development, and changing lifestyles and business practices. Takeaway for practice: Environmental planning ideas have been around for the past century and underlie the currently popular concept of planning for sustainability. However, environmental planning has been only modestly effective at influencing business practices and lifestyles. To change this, federal and local governments will have to lead by example, pursuing environmental sustainability as seriously as they pursue economic growth. Research support: None. 相似文献
15.
ABSTRACTThis paper introduces a simulation-based sustainable life of pipe (SLP) determination for a water distribution system (WDS) using a triple top line (TTL) sustainability index (SI). SLP is the pipe replacement time maximizing SI. The approach is applied to the U-City system, a hypothetical urban WDS. Two case studies were conducted: (1) SLP to identify a conservation goal and (2) optimal SLP analysis using revised harmony search (ReHS) to discover replacement timing. The results show conservation targeting a 1% annual rate of demand growth maximizes the SI. And after optimizing the SLP, earlier pipe replacement and higher benefits result from the maximum SI approach compared to the least cost approach. In conclusion, the demonstrations show that using the TTL-based SI can guide demand management and pipe replacement strategies to maximize a comprehensive set of sustainability benefits. 相似文献
16.
This paper describes three analyses to examine differences in construction company POT profitability between (1) different financial years and (2) different sizes of companies. In the first analysis, the aggregated profitability of a sample of 80 UK general contractors was found not to differ significantly from 3.23% for each year of the period examined. The size (turnover) of companies, however, was significantly and positively correlated with profitability. The second analysis, of a sub-sample of eight very large companies, showed that profitability enhancement was associated with diversification into house building and other related activities. The third analysis, of 110 speculative house builders, showed profit margins to be around four times those of general contractors but uncorrelated with company size. Systematic changes were found, however, over the period involved. In all cases, the variability of profitability between companies was found to reduce with company size, implying a greater consistency in the financial performance of larger companies. 相似文献
17.
《Urban Water Journal》2013,10(6):568-575
ABSTRACTModeling and forecasting for various time horizons of urban water supply are important for different operations within a utility company. This study proposes the ‘elliptic orbit model’ for daily urban water supply prediction from the viewpoint of time-series analysis. As additional efforts and costs are required to acquire and predict more different forecast variables, it is argued that many studies failed to carefully check whether such efforts and costs were deserved and to what degree they might ameliorate the prediction accuracy. Thus predictive modeling based on available water supply data has its own advantages. Only the water-supply time-sequence data is used and mapped into the polar coordinates to design the proposed ‘elliptic orbit model’, so the purpose of this study is to present one vivid approach for forecasting daily urban water supply in an intuitive and concise way. The proposed model archives satisfying experimental results and may inspire other applications. 相似文献
18.
过江隧道深基坑中SMW工法加钢支撑围护结构现场监测分析 总被引:1,自引:0,他引:1
杭州庆春路过江隧道是“钱江第一隧”,其江北岸基坑是典型的粉性土基坑,最大开挖深度16 m,主要采用SMW工法(劲性水泥土搅拌连续墙)加钢支撑的围护结构体系,围护桩最长达27 m。基坑开挖过程监测数据表明:围护桩的最大水平位移与开挖深度及时间密切相关,支撑的架设及内部结构能很好限制桩体变形;气温、降雨等外界条件的变化对支撑轴力的影响较大,临近基坑支撑的拆除也会产生重大影响;钢支撑轴力均未达到设计值,应对设计方案进行优化;基坑降水及由此引发的渗流会改变土体有效应力,是基坑周围地表沉降的主要原因,同时相邻基坑的施工也会产生一定影响;地下水位的变化能很好反应围护桩的止水效果,可作为判断基坑是否出现漏水的指标。对于粉性土基坑,有效控制基坑周围水的变化,对保持基坑安全有重要意义。 相似文献
19.
The outbreak of COVID-19 led to restrictions on movements and activities, which presented a serious challenge to the resilience of the water sector. It is essential to understand how successfully water companies responded to this unprecedented event so effective plans can be built for future disruptive events. This study aimed to evaluate how the water sectors in the UK and Ireland were affected from a holistic sustainability and resilience-based perspective. Using pre-COVID data for 18 indicators of company performance and comparing them to the first year of the pandemic, the direction and magnitudes of change varied across companies. Financial indicators were significantly negatively affected, with interest cover ratio, post-tax return on regulated equity, and operating profit, exhibiting the greatest average declines of 21%, 21%, and 18%, respectively, a trend that would be dangerous to provisions and company operations if continued. Despite this, service and environmental indicators improved during the first year of the pandemic, exemplified by unplanned outage, risk of sewer storm flooding, and water quality compliance risk decreasing by a mean average of 37%, 32%, and 27%, respectively. Analysis using the Hicks-Moorsteen Productivity Index concluded that average productivity increased by 35%. The results suggest that the water sector was relatively resilient to the COVID-19 pandemic in terms of services, but adverse effects may have manifested in a deteriorated financial position that could exacerbate future challenges arising from exogenous pressures such as climate change. Specific advice for the UK water sector is to scrutinize non-critical spending, such as shareholder payments, during periods of economic downturn to ensure essential capital projects can be carried out. Although results are temporal and indicator selection sensitive, we recommend that policy, regulation, and corporate culture embrace frameworks that support long-term resilience to since the relative success in response to COVID-19 does not guarantee future success against differing challenges. This study generates a timely yet tentative insight into the diverse performance of the water sector during the pandemic, pertinent to the water industry, regulators, academia, and the public. 相似文献
20.
Benchmarking can be a useful tool for utility companies to improve their efficiency, offering many potential positives such as assessing performance objectively, exposing areas where improvement is needed, and identifying best performing companies, ultimately illuminating possible strategies for poorer performers to implement. Despite these positives, the challenge remains of how to compare the performance of different organisations from different sectors. This research aimed to develop a methodology to effectively compare companies across sectors using UK utilities across the water and sewage, energy, and communications sectors as a case study. A methodology was constructed based on service, environmental, and financial metrics, and cross-sector benchmarking was undertaken, which generated performance scores based on company metrics relative to sector peers. This circumnavigated issues of indicators often being mismatched across sectors and the lack of relevance and context when sectors do use similar indicators. Results showed that the sample of 18 utilities had two distinct clusters, one of eight sector leaders and the other of ten lower performers. Sky had the highest overall score of 13.5 (maximum 15), suggesting it significantly outperformed the rest of the communications sector. Similarly, British Gas and SSE lead the energy sector, whilst Wessex, Severn Trent, and United Utilities lead the way for water and sewage companies. The two distinct groups of sector leaders and lower performers can be employed to identify other companies that may offer learning opportunities. Top performers can assess top performers in other sectors to identify how they might continue improving, rather than be potentially limited within their sectors. Conversely, lower-performing companies can look within and across sectors to identify best practices to improve their performance. The methodological development and UK utility sustainability results collectively provide novel insight into the water, energy, and communication sectors and contribute to the international academic literature on benchmarking by illustrating an alternative and unique solution to comparing diverse sectors in any region. 相似文献