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1.
Results are presented from a monitoring study of the electricity consumption of a sample of UK domestic buildings. Five-minutely average whole house power consumption was recorded for 72 dwellings at five sites over a 2-year monitoring period. The mean annual electricity consumption for the households increased significantly by 4.5% (t = 1.9; p < 0.05, one-tailed) from the first to the second year of monitoring. New techniques are developed which estimate the electricity consumption of different appliance groups, based on analysis of the five-minutely monitored data. The overall increase in electricity consumption is attributed to a 10.2% increase in the consumption of ‘standby’ appliances (such as televisions and consumer electronics) and a 4.7% increase in the consumption of ‘active’ appliance (such as lighting, kettles and electric showers). The consumption of different energy user groups (low, medium and high) is also investigated and low and high users are identified as contributing to the overall increase in consumption. The need for further investigation, such as quantitative and qualitative studies, to improve understanding in domestic electricity consumption is discussed.  相似文献   

2.
This paper proposes that projects and programmes can be empirically distinguished by the way in which they are associated with expectations and evaluations of success and failure. Support for the proposition is grounded in analysis of over sixteen hundred examples of occurrences of the terms ‘project’ and ‘programme’ with ‘success’ and ‘failure’ derived from the Oxford English Corpus (OEC). The OEC is a structured and coded database of over two billion words of naturally occurring English collected from the World Wide Web. The analysis highlights that project and programme are each modified by the terms ‘success’ and ‘failure’ in significantly different ways, indicating that they are conceptually distinct phenomena. These findings imply that academics must be cautious in their use of language in investigations of project and programme evaluations, and that practitioners should consider the implications of considering programmes as ‘scaled‐up’ projects, given their propensity to different evaluation outcomes.  相似文献   

3.
This paper reports a study of the subjective preference to daylit indoor environment of a residential room using conjoint analysis, which is a highly reputable method used to analyze the mutual relationships among different attributes. Seven influential attributes were selected in the view of daylight performance assessment. They include ‘general brightness’, ‘desktop brightness’, ‘perceived glare’, ‘sunlight penetration’, ‘quality of view’, ‘user friendliness of shading control’ and ‘impact on energy’. Each of them has two levels. A total of eight combinations (profiles) of attributes with various levels were established by adopting fractional factorial design. Subjects were asked to rank-order the eight profiles according to their preference in terms of daylit environment of a residential room. The study aims at finding out the relative impact of the seven selected attributes to the overall daylight performance and seeking an organized assessment method for a residential daylit environment. Conjoint analysis found that the seven attributes have importance level in the order of ‘quality of view’, ‘general brightness’, ‘impact on energy’, ‘user friendliness of shading control’, ‘perceived glare’, ‘desktop brightness’ and ‘sunlight penetration’.  相似文献   

4.
Real-time PCR absolute quantification applications are becoming more common in the recreational and drinking water quality industries. Many methods rely on the use of standard curves to make estimates of DNA target concentrations in unknown samples. Traditional absolute quantification approaches dictate that a standard curve must accompany each experimental run. However, the generation of a standard curve for each qPCR experiment set-up can be expensive and time consuming, especially for studies with large numbers of unknown samples. As a result, many researchers have adopted a master calibration strategy where a single curve is derived from DNA standard measurements generated from multiple instrument runs. However, a master curve can inflate uncertainty associated with intercept and slope parameters and decrease the accuracy of unknown sample DNA target concentration estimates. Here we report two alternative strategies termed ‘pooled’ and ‘mixed’ for the generation of calibration equations from absolute standard curves which can help reduce the cost and time of laboratory testing, as well as the uncertainty in calibration model parameter estimates. In this study, four different strategies for generating calibration models were compared based on a series of repeated experiments for two different qPCR assays using a Monte Carlo Markov Chain method. The hierarchical Bayesian approach allowed for the comparison of uncertainty in intercept and slope model parameters and the optimization of experiment design. Data suggests that the ‘pooled’ model can reduce uncertainty in both slope and intercept parameter estimates compared to the traditional single curve approach. In addition, the ‘mixed’ model achieved uncertainty estimates similar to the ‘single’ model while increasing the number of available reaction wells per instrument run.  相似文献   

5.
通过城市生活垃圾与污水厂脱水污泥的混合填埋模拟实验,研究了添加污泥对垃圾降解及填埋气产生过程的影响,实验结果表明,在填埋垃圾中添加污泥起到了接种微生物的作用,加快了有机垃圾的降解与填埋气的产生,产气速率较生活垃圾直接填埋提高30%以上,填埋气中CH4浓度可达到64%,与没有添加污泥相比,填埋气中CH4含量有较大幅度的提高,有利于填埋气的资源化利用,同时也可为污泥的资源化利用提供经济可行的途径。  相似文献   

6.
Engineering properties of municipal solid waste(MSW) depend largely on the waste's initial composition and degree of degradation.MSWs in developing countries usually have a high kitchen waste content(called HKWC MSW).After comparing and analyzing the laboratory and field test results of physical composition,hydraulic properties,gas generation and gas permeability,and mechanical properties for HKWC MSW and low kitchen waste content MSW(called LKWC MSW),the following findings were obtained:(1) HKWC MSW has a higher initial water content(IWC) than LKWC MSW,but the field capacities of decomposed HKWC and LKWC MSWs are similar;(2) the hydraulic conductivity and gas permeability for HKWC MSW are both an order of magnitude smaller than those for LKWC MSW;(3)compared with LKWC MSW,HKWC MSW has a higher landfill gas(LFG) generation rate but a shorter duration and a lower potential capacity;(4) the primary compression feature for decomposed HKWC MSW is similar to that of decomposed LKWC MSW,but the compression induced by degradation of HKWC MSW is greater than that of LKWC MSW;and(5) the shear strength of HKWC MSW changes significantly with time and strain.Based on the differences of engineering properties between these two kinds of MSWs,the geo-environmental issues in HKWC MSW landfills were analyzed,including high leachate production,high leachate mounds,low LFG collection efficiency,large settlement and slope stability problem,and corresponding advice for the management and design of HKWC MSW landfills was recommended.  相似文献   

7.
As global considerations about the environment are on the increase, those working in the field of architecture have carried out many initiatives to protect the environment. The KGBCC (Korean Green Building Certification Criteria) was developed in 2000 in Korea and has operated since 2002. The Apartment for Good Living competition has been held since 1996 as social interest in green residences increases. The objective of this study is to suggest improvements and further direction for the KGBCC by comparison with resident satisfaction levels. For this study, a questionnaire about satisfaction levels was taken by residents of KGBCC-certified apartments and ‘Apartment for Good Living’-awarded apartment in Dongtan District, Hwasung City, Gyeonggi-do, Korea. The survey results were compared and analyzed, and the comparison results of both apartment and the improvement direction of KGBCC were verified.  相似文献   

8.
Microbial source tracking techniques are used in the UK to provide an evidence-base to guide major expenditure decisions and/or regulatory action relating to sewage disposal. Consequently, it is imperative that the techniques used robustly index faecal indicator organisms (FIOs) that are the regulatory parameters for bathing and shellfish harvesting areas. This study reports a ‘field-scale’ test of microbial source tracking (MST) based on the quantitative PCR analyses of Bacteroidales 16S rRNA genetic marker sequences. The project acquired data to test the operational utility of quantitative Bacteroidales MST data, comparing it with FIO concentrations in streams, effluents and bathing waters. Overall, the data did not exhibit a consistent pattern of significant correlations between Bacteroidales MST parameters and FIOs within the different sample matrices (i.e. rivers, bathing waters and/or effluents). Consequently, there was little evidence from this study that reported concentrations and/or percentages of human and/or ruminant faecal loadings (that are based on Bacteroidales MST gene copy numbers) offer a credible evidence-base describing FIO contributions to receiving water ‘non-compliance’. The study also showed (i) there was no significant attenuation of the Bacteroidales gene copy number ‘signal’ through the UV disinfection process; and (ii) single non-compliant samples submitted for Bacteroidales MST analysis, do not reliably characterise the balance of faecal loadings due to the high variability in the MST signal observed.At this stage in the development of the MST tool deployed, it would be imprudent to use the percentage human and/or ruminant contributions (i.e. as indicated by MST data acquired at a bathing water) as the sole or principal element in the evidence-base used to guide major expenditure decisions and/or regulatory action.  相似文献   

9.
The organic matter contained in municipal solid waste (MSW) and in the MSW fractions obtained by mechanical separation has strong environmental impact when the waste is used as landfill. This is partly due to the biological activity that occurs under anaerobic conditions. Negative effects on the environment include unpleasant odors, biogas, leachate and biomass self-heating. Measuring the biological reactivity of waste with the help of indicators is an important tool to prevent waste impact. The aim of this study was to develop an index capable of describing the aerobic reactivity of waste, using both biological and chemical indicators. To develop this index, 71 MSW and MSW-product samples, including biologically treated MSW and mechanically separated MSW fractions, were analyzed. Fifty of the 71 samples analyzed represented MSWs and their derived products collected from a number of Italian waste plants and sites. The remaining 21 were MSW samples collected at different times during 8 different full-scale aerobic biological processes in four treatment plants used to reduce the biological reactivity of wastes. Five of these processes used the entire (unsorted) MSW, while the remaining three used the organic fraction of the MSW obtained by mechanical pre-treatment (waste sieving). Respirometric activity (Dynamic Respiration Index, DRI) and eluates characterization (chemical oxygen demand--COD, and 5 days biological oxygen demand--BOD5) were used as indicators of waste strength, as they had previously been reported to be indirect measures of waste impact on landfill. Summarizing all studied indicators, Principal Component Analysis (PCA) was used to develop the Putrescibility Index (Ip). The results revealed Ip index of 204+/-33 (mean+/-standard deviation) and 159+/-14 for the organic fraction of MSW and MSW untreated waste respectively, and of 106+/-16 and 101+/-22 for the corresponding biologically treated waste.  相似文献   

10.
The environmental impacts of municipal solid waste (MSW) management have been highlighted in China, due to the continually increasing amount of MSW being generated and the limited capacity of waste treatment facilities. Of particular interest is greenhouse gas (GHG) mitigation, aided by the Kyoto Mechanisms. China is an important case study for this global issue; however, an analysis of the entire life cycle of MSW management on GHG emissions is not available for China. This study evaluates the current and possible patterns of MSW management with regard to GHG emissions, using life cycle assessment (LCA), based on the Tianjin case. We assess the baseline scenario, reflecting the existing MSW management system, as well as a set of alternative scenarios, five exploring waste treatment technology innovations and one exploring integrated MSW management, to quantitatively predict potentials of GHG mitigation for Tianjin. Additionally, a sensitivity analysis is used to investigate the influence of landfill gas (LFG) collection efficiency, recycling rate and methodological choice, especially allocation, on the outcomes. The results show GHG emissions from Tianjin's MSW management system amount to 467.34 Mg CO2 eq. per year, based on the treatment of MSW collected in the central districts in 2006, and the key issue is LFG released. The integrated MSW management scenario, combining different improvement options, shows the highest GHG mitigation potential. Given the limited financial support and the current waste management practice in Tianjin, LFG utilization scenario would be the preferred choice. The sensitivity analysis of recycling rate shows an approximately linear relation of inverse proportion between recycling rate and total GHG emissions. Kitchen waste composting makes a considerable contribution to total GHG emissions reduction. Allocation choices result in differences in total quantitative outcomes, but preference orders and contributions analysis are found to be robust, suggesting LCA can support decision making.  相似文献   

11.
The lines of ‘damage-begin’ and ‘specimen-break’ for dynamic loading of a geogrid were determined in a series of laboratory testing. The cyclic load ratio was set to R = 0.5, loading frequency f = 10 Hz and f = 3 Hz. The test results show clearly that the chosen procedure for the determination and analysis of the beginning of damage and break is reproducible and allow for safe extrapolation for lower load levels. Furthermore the method chosen enables explicit decrease of the required testing time. The assumption of linear damage accumulation was examined in two-step-trials. The number of load cycles to ‘break’ evaluated in ‘one-step-tests’ compared with those of ‘two-step-loading’ are practically the same. The existence of ‘damage-lines’ for the examined geogrid under a dynamic pulsating load of 10 Hz and 3 Hz and a R-value of 0.5 could be verified. Damage of the specimens occurs only for load-cycles lying between the ‘damage-line’ and the ‘stress-cycle-diagram’ (‘Woehler-curve’). When it comes to dimensioning against ‘damage-beginning’ or ‘break’, higher loading frequencies present the critical case.  相似文献   

12.
Classification of contaminated land is important for risk assessment and so it is vital to understand and quantify all of the uncertainties that are involved in the assessment of contaminated land. This paper uses a case study to compare two methods for assessing the uncertainty in site investigations (uncertainty of individual measurements, including that from sampling, and uncertainty of the mean value of all measurements within an area) and how the different methods affect the decisions made about a site. Using the ‘uncertainty of the mean value’ there is shown to be no significant possibility of ‘significant harm’ under UK guidance at one particular test site, but if you consider the ‘uncertainty of the measurements’ a significant proportion (50%) of the site is shown to be possibly contaminated. This raises doubts as to whether the current method using ‘uncertainty of the mean’ is sufficiently robust, and suggests that ‘uncertainty of measurement’ information may be preferable, or at least beneficial when used in conjunction.  相似文献   

13.
Transition regions: Regional-national eco-innovation systems and strategies   总被引:2,自引:0,他引:2  
The key phenomenon around which the paper is constructed, given its core interest in the transition from a fossil fuels energy regime to a zero emissions and/or renewable energy regime (sometimes also ‘post-hydrocarbons’ regime; Smith, 2008), is the notion and explanation of ‘transition regions’. These are sub-national territories, usually with some degree of devolved governance in the fields of innovation, economic development and energy that, for reasons to be demonstrated, act as regional ‘lighthouses’ for eco-innovation both to other regions and countries. These are the places that are subject to ‘learning visits’ by global policy-makers and other interested parties eager to learn how success was achieved. Because regions differ within state-systems, the case material is presented according to three kinds of political model. These are, first, the liberal market model, notably north America and the UK; second is the co-ordinated market model such as Germany and some Nordic countries; and third hybrids which have a reasonably entrepreneurial economic climate typical of the ‘liberal market’ model but strong welfare states, more typical of the ‘co-ordinated market’ model such as Denmark, a small state, and China, a large one. Finally, each of six cases will be presented in the sequence of the ‘system’ and regional governance of ‘transition regions’ first, with the nature and role of the national eco-innovation regime summarised afterwards where top-down governmental influence is clearly visible, even weakly. Also eco-innovations that are broadly in the same field, such as renewable energy production, or electric vehicle consumption are studied, giving maximum comparative value from their emergence in different countries and regions.  相似文献   

14.
Residents' engagement in pro-environmental behavior is crucial in tackling the environmental challenges that cities face. Research shows that residents who are attached to their place of residence are more likely to engage in pro-environmental behavior and, consequently, place attachment has been prescribed as a pro-environmental policy. However, previous research has not explored which specific aspect of place attachment is most effective at promoting different types of pro-environmental behavior. Furthermore, in the context of big cities which typically host both natives and migrants, different resident groups may be attached to their places of residence due to different reasons. This implies that different types of place attachment policies may be required for each group of residents. Using survey data in Beijing, China, we find that the social bonding dimension of place attachment is most effective at promoting pro-environmental behavior and that this relationship is stronger for native born residents and those with longer residency length. We also find that the effect of place social bonding is stronger for high-effort than low-effort pro-environmental behavior. Our findings have implications for the design and implementation of place attachment policies for local authorities in Beijing and in other big cities where different groups of residents cohabit. Generally, our research results imply that place attachment policies that focus on promoting social connections amongst urban residents to their place of residence will be most effective.  相似文献   

15.
This paper investigates the potential CO2 emission reductions related to a partial switch from fossil fuel-based heat and electricity generation to renewable wood waste-based systems in Flanders. The results show that valorization in large-scale CHP (combined heat and power) systems and co-firing in coal plants have the largest CO2 reduction per TJ wood waste. However, at current co-firing rates of 10%, the CO2 reduction per GWh of electricity that can be achieved by co-firing in coal plants is five times lower than the CO2 reduction per GWh of large-scale CHP. Moreover, analysis of the effect of government support for co-firing of wood waste in coal-fired power plants on the marginal costs of electricity generation plants reveals that the effect of the European Emission Trading Scheme (EU ETS) is effectively counterbalanced. This is due to the fact that biomass integrated gasification combined cycles (BIGCC) are not yet commercially available. An increase of the fraction of coal-based electricity in the total electricity generation from 8 to 10% at the expense of the fraction of gas-based electricity due to the government support for co-firing wood waste, would compensate entirely for the CO2 reduction by substitution of coal by wood waste. This clearly illustrates the possibility of a ‘rebound’ effect on the CO2 reduction due to government support for co-combustion of wood waste in an electricity generation system with large installed capacity of coal- and gas-based power plants, such as the Belgian one.  相似文献   

16.
Due to prolonged droughts in recent years, the use of rainwater tanks in urban areas has increased in Australia. In order to apportion sources of contribution to heavy metal and ionic contaminants in rainwater tanks in Brisbane, a subtropical urban area in Australia, monthly tank water samples (24 sites, 31 tanks) and concurrent bulk deposition samples (18 sites) were collected during mainly April 2007-March 2008. The samples were analysed for acid-soluble metals, soluble anions, total inorganic carbon and total organic carbon, and characteristics such as total solid and pH. The Positive Matrix Factorisation model, EPA PMF 3.0, was used to apportion sources of contribution to the contaminants. Four source factors were identified for the bulk deposition samples, including ‘crustal matter/sea salt’, ‘car exhausts/road side dust’, ‘industrial dust’ and ‘aged sea salt/secondary aerosols’. For the tank water samples, apart from these atmospheric deposition related factors which contributed in total to 65% of the total contaminant concentration on average, another six rainwater collection system related factors were identified, including ‘plumbing’, ‘building material’, ‘galvanizing’, ‘roofing’, ‘steel’ and ‘lead flashing/paint’ (contributing in total to 35% of the total concentration on average). The Australian Drinking Water Guideline for lead was exceeded in 15% of the tank water samples. The collection system related factors, in particular the ‘lead flashing/paint’ factor, contributed to 79% of the lead in the tank water samples on average. The concentration of lead in tank water was found to vary with various environmental and collection system factors, in particular the presence of lead flashing on the roof. The results also indicated the important role of sludge dynamics inside the tank on the quality of tank water.  相似文献   

17.
18.
工业污水和生活污水排放量日益增多,污水处理厂污泥产量日趋加大,污泥填埋关键技术问题已成为当今环境工程以及环境岩土工程的热点问题之一。污泥和垃圾混合填埋在其他国家已得到应用,但由于目前中国关于污泥及其城市生活垃圾混合样的基础性室内试验成果不多,对污泥与城市垃圾混合样的工程力学特性及其混合填埋的适宜比例等不甚了解,从而导致中国污泥垃圾混合填埋工程事故频繁发生。对不同配比的污泥与城市生活垃圾混合样进行了固结压缩实验、三轴固结不排水实验、无侧限抗压强度实验,得出污泥与城市生活垃圾混合样的工程力学特性;同时,用ANSYS数值模拟方法,对不同配合比的污泥城市生活垃圾混合填埋边坡的稳定性进行分析,从而对污泥与城市生活垃圾混合填埋的适宜配合比及其稳定安全问题提出理论支撑。  相似文献   

19.
The availability of innumerable intelligent building (IB) products, and the current dearth of inclusive building component selection methods suggest that decision makers might be confronted with the quandary of forming a particular combination of components to suit the needs of a specific IB project. Despite this problem, few empirical studies have so far been undertaken to analyse the selection of the IB systems, and to identify key selection criteria for major IB systems. This study is designed to fill these research gaps. Two surveys: a general survey and the analytic hierarchy process (AHP) survey are proposed to achieve these objectives. The first general survey aims to collect general views from IB experts and practitioners to identify the perceived critical selection criteria, while the AHP survey was conducted to prioritize and assign the important weightings for the perceived criteria in the general survey. Results generally suggest that each IB system was determined by a disparate set of selection criteria with different weightings. ‘Work efficiency’ is perceived to be most important core selection criterion for various IB systems, while ‘user comfort’, ‘safety’ and ‘cost effectiveness’ are also considered to be significant. Two sub-criteria, ‘reliability’ and ‘operating and maintenance costs’, are regarded as prime factors to be considered in selecting IB systems. The current study contributes to the industry and IB research in at least two aspects. First, it widens the understanding of the selection criteria, as well as their degree of importance, of the IB systems. It also adopts a multi-criteria AHP approach which is a new method to analyse and select the building systems in IB. Further research would investigate the inter-relationship amongst the selection criteria.  相似文献   

20.
An increasing number of change processes and initiatives are organized and implemented as projects, often through the formation of ‘large-scale transformation projects’ (LST), involving a great number of specialists, departments, partners, development work, and knowledge bases. The theoretical foundation that supports the choice of managing change as projects and, in effect, the role of project management has received surprisingly little attention in the current literature. In this paper, we present a model where the success of change initiatives is explained by the quality of project management, which in turn is determined by the quality of knowledge integration. The outlined model highlights knowledge integration as a process determined by the scope and speed of change, which typically result in problems with synchronization of activities within an LST project. Our model draws on the idea of ‘knowledge entrainment’ to explain the fact that different parts (organizations, teams, individuals) tend to develop different time orientations and hence rely on different cycles of knowledge processes. This has important effects on the absorptive capacity of the involved parts of the project and the amount of information and knowledge that the project can digest. This paper discusses different knowledge-entrainment mechanisms and their effects on the role and practice of project management. Empirical data from an LST project in Posten, one of Northern Europe’s largest messaging and logistics operators, illustrate the model. The paper contributes to the analysis of the relationships between knowledge integration and time, particularly in LST projects.  相似文献   

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