| publications-4501 |
article |
2006 |
Hoffmann, M. and Hoffmann, Mark and Worthington, Andrew C. and Worthington, Andrew C. and Higgs, Helen and Higgs, Helen |
Urban water demand with fixed volumetric charging in a large municipality: the case of Brisbane, Australia * |
Australian Journal of Agricultural and Resource Economics |
10.1111/j.1467-8489.2006.00339.x |
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This paper uses suburb-level quarterly data to model residential water demand in Brisbane, Australia, from 1998 to 2003. In this system, residential consumption is charged using a fixed annual service fee with no water entitlement followed by a fixed volumetric charge per kilolitre. Water demand is specified as average quarterly household water consumption and the demand characteristics include the marginal price of water, household income and size, and the number of rainy and warm days. The findings not only confirm residential water as price and income inelastic, but also that the price and income elasticity of demand in owner-occupied households is higher than in rented households. The results also show that weather, particularly summer months and the number of rainy days, exerts a strong influence on residential water consumption. |
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| publications-4502 |
article |
2006 |
Gilg, Andrew W. and Gilg, Andrew W. and Barr, Stewart and Barr, Stewart |
Behavioural attitudes towards water saving? Evidence from a study of environmental actions |
Ecological Economics |
10.1016/j.ecolecon.2005.04.010 |
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| publications-4503 |
article |
1994 |
Simpson, Angus R. and Simpson, Angus R. and Dandy, Graeme C. and Dandy, Graeme C. and Murphy, Laurence and Murphy, Laurence J. and Murphy, L. |
Genetic algorithms compared to other techniques for pipe optimization |
Journal of Water Resources Planning and Management |
10.1061/(asce)0733-9496(1994)120:4(423) |
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The genetic algorithm technique is a relatively new optimization technique. In this paper we present a methodology for optimizing pipe networks using genetic algorithms. Unknown decision variables are coded as binary strings. We investigate a three-operator genetic algorithm comprising reproduction, crossover, and mutation. Results are compared with the techniques of complete enumeration and nonlinear programming. We apply the optimization techniques to a case study pipe network. The genetic algorithm technique finds the global optimum in relatively few evaluations compared to the size of the search space. |
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| publications-4504 |
article |
2004 |
Campbell, Heather E. and Campbell, Heather E. and Johnson, Ryan M. and Johnson, Ryan M. and Larson, Elizabeth Hunt and Larson, Elizabeth Hunt and Larson, Elizabeth Hunt |
Prices, Devices, People, or Rules: The Relative Effectiveness of Policy Instruments in Water Conservation1 |
Review of Policy Research |
10.1111/j.1541-1338.2004.00099.x |
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Water conservation policy is a natural laboratory for addressing general issues of relevance to policy analysis and public administration, particularly the relative effectiveness of policies in changing human behavior. Using multivariate regression analysis of a dataset comprised of more than 200,000 monthly observations of more than 19,000 household accounts over six years, this paper makes three main contributions. First, it contributes to the substantive area of water conservation policy by analyzing what works. Second, it contributes to our understanding of generic policy instruments. Third, it raises an important issue regarding standard assumptions about selection bias. The results support earlier work warning that offsetting behavior can negate engineering solutions to policy problems, but further indicate that adding communication to engineering solutions can create cooperation that overcomes offsetting behavior. They also provide evidence that appropriate regulation can be effective, and that pricing can be effective even when price elasticities of demand are low. Copyright 2004 by The Policy Studies Association. |
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| publications-4505 |
article |
2006 |
Gaudin, Sylvestre and Gaudin, Sylvestre |
Effect of price information on residential water demand |
Applied Economics |
10.1080/00036840500397499 |
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Microeconomic theory predicts that people decrease consumption when price increases, the magnitude of the effect depending on price elasticity. The law of demand, however, implicitly assumes that consumers know prices, an assumption that is not always satisfied in markets with ex post billing. When prices are not transparent, elasticity estimates are potentially lower than their full information potential. Evidence of low price elasticity abounds in residential water demand studies, limiting the effectiveness and desirability of using price signals as a conservation tool. It is hypothesized that resident's sluggish response to price is partly due to the absence of price information on water bills. Differences in the informational content of bills are documented for the first time on the basis of sample bills collected from 383 utilities across the USA. A standard aggregate water demand model is augmented with qualitative variables describing differences in billing information, allowing such variables to affect the intensity with which consumers respond to price signals. No evidence is found that non-price information items affect price elasticity but there is a statistically significant effect in the case of price-related information; in our sample, price elasticity increases by 30\% or more when price information is given on the bill. |
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| publications-4506 |
article |
2006 |
Domene, Elena and Domene, Elena and SaurΔ±Μ, David and SaurΓ, David |
Urbanisation and Water Consumption: Influencing Factors in the Metropolitan Region of Barcelona: |
Urban Studies |
10.1080/00420980600749969 |
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This paper is concerned with the relationships between urbanisation and residential water consumption, taking as a case study the Metropolitan Region of Barcelona. More precisely, it investigates the influence of certain demographic, behavioural and housing factors on this consumption using descriptive statistics and a regression analysis. The data are derived from a sample of 532 households in 22 municipalities of the study area. Results show that income, housing type, members per household, the presence of outdoor uses (garden and swimming pool), the kind of species planted in the garden and consumer behaviour towards conservation practices play a significant role in explaining variations in water consumption. It is concluded that, along with prices and incomes, further research is needed on other demographic and housing variables in order to obtain a more comprehensive understanding of the determinants of domestic water consumption in areas periodically affected by water stress. |
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| publications-4507 |
article |
2018 |
Qi, Qinglin and Qi, Qinglin and Qi, Qinglin and Tao, Fei and Tao, Fei and Zuo, Ying and Zuo, Ying and Zhao, Dongming and Zhao, Dongming and Zhao, Dongming |
Digital Twin Service towards Smart Manufacturing |
Procedia CIRP |
10.1016/j.procir.2018.03.103 |
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Abstract Digital twin provides an effective way for the cyber-physical integration of manufacturing. Meanwhile, smart manufacturing services could optimize the entire business processes and operation procedure of manufacturing, to achieve a new higher level of productivity. The combination of smart manufacturing services and digital twin would radically change product design, manufacturing, usage, MRO and other processes. Combined with the services, the digital twin will generate more reasonable manufacturing planning and precise production control to help achieve smart manufacturing, through the two-way connectivity between the virtual and physical worlds of manufacturing. This paper specifies and highlights how manufacturing services and digital twin are converged together and the various components of digital twin are used by manufacturers in the form of services. |
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| publications-4508 |
article |
1971 |
Schelling, Thomas C. and Schelling, Thomas C. |
Dynamic models of segregation |
Journal of Mathematical Sociology |
10.1080/0022250x.1971.9989794 |
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Some segregation results from the practices of organizations, some from specialized communication systems, some from correlation with a variable that is nonβ€random; and some results from the interplay of individual choices. This is an abstract study of the interactive dynamics of discriminatory individual choices. One model is a simulation in which individual members of two recognizable groups distribute themselves in neighborhoods defined by reference to their own locations. A second model is analytic and deals with compartmented space. A final section applies the analytics to β€neighborhood tipping.’ The systemic effects are found to be overwhelming: there is no simple correspondence of individual incentive to collective results. Exaggerated separation and patterning result from the dynamics of movement. Inferences about individual motives can usually not be drawn from aggregate patterns. Some unexpected phenomena, like density and vacancy, are generated. A general theory of β€tipping’ begins to emerge. |
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| publications-4509 |
article |
1980 |
Agthe, Donald E. and Agthe, Donald E. and Billings, R. Bruce and Billings, R. Bruce |
Dynamic models of residential water demand |
Water Resources Research |
10.1029/wr016i003p00476 |
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Static, Fisher-Kaysen, Koyck, flow adjustment (Bergstrom), and stock adjustment econometric models of the demand for residential water are tested for their ability to explain the monthly residential demand for water in Tucson. Marginal price and a second price-related variable are used in the estimating equations to account for block rates and fixed charges in the water rate schedule. The other independent vari ables are household income and evapotranspiration minus rainfall. The Fisher-Kaysen model produced very poor statistical results. The estimated long-run marginal price elasticities of demand varied from β’0.266 to β’0.705. The short-run marginal price elasticity estimates varied from β’0.179 to β’0.358 except for the linear flow adjustment model with a value of β’2.226. This unexpected result casts some doubt on the applicability of the flow adjustment model to estimating the price elasticity of demand with monthly data. |
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| publications-4510 |
article |
1982 |
Howe, Charles W. and Howe, Charles W. |
The impact of price on residential water demand: Some new insights |
Water Resources Research |
10.1029/wr018i004p00713 |
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Marginal price elasticities are reestimated from the Johns Hopkins Residential Water Use Project data of 1963–1965, utilizing more appropriate forms of household water demand functions derived from recent advances in consumer theory that account for the effects of a rate structure. Winter season elasticity is found to be a very low β’0.06 compared to β’0.23 in a 1967 study. For summer demands, price elasticities are found to be lower than earlier estimates, namely, β’0.568 versus β’0.860 for eastern U.S. areas and β’0.427 versus β’0.519 for western areas. |
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