Dissertations / Theses: 'End use water models'

1

Gato, Shirley, and s3024038@rmit edu au. "Forecasting Urban Residential Water Demand." RMIT University. Civil, Environmental and Chemical Engineering, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070202.113452.

Full text

Abstract:

The city of Melbourne in Victoria, Australia has been recognised as having high quality drinking water, but like other urban cities in the world, its growing population means increasing water demand. Melbourne is also already on its eight year of dry climatic conditions and is currently experiencing a drought that forced water authorities to impose water restrictions after 20 years of unrestricted supply. The current drought, dwindling supplies and possible impact of climate change highlight the importance of making better use of this precious resource. The Water Resources Strategy has been developed for Melbourne, which serve as the basis for the Victorian Government to set per capita consumption reduction targets of 15%, 25% and 30% by 2010, 2015 and 2020 respectively. The strategy was developed to ensure a continuation of a safe, reliable and cost effective water supply that is environmentally sustainable in the long term. This is in recognition that population growth and water consumption will eventually require additional supplies of water (Water Resources Strategy Committee for the Melbourne Area 2002). One of the key findings of the National Land and Water Resources Audit's Australian Water Resources Assessment 2000 is the lack of detailed knowledge about the end use (Australian Water Association 2001). The

APA, Harvard, Vancouver, ISO, and other styles

2

Scheepers, Hester Maria. "Deriving peak factors for residential indoor water demand by means of a probability based end-use model." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71639.

Full text

Abstract:

Thesis (MScEng)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: The expected peak water demand in a water distribution system (WDS) is an important consideration for WDS design purposes. In South Africa the most common method of estimating peak demand is by multiplying the average demand by a dimensionless peak factor. A peak factor is the ratio between the maximum flow rate (which refers to the largest volume of flow to be received during a relatively short time period, say , expressed as the average volume per unit time), and the average flow rate over an extended time period. The magnitude of the peak factor will vary, for a given daily water demand pattern, depending on the chosen value of . The design guidelines available give no clear indication of the time intervals most appropriate for different peak factor applications. It is therefore important to gain a better understanding regarding the effect of on the derived peak factor. A probability based end-use model was constructed as part of this study to derive diurnal residential indoor water demand patterns on a temporal scale of one second. These stochastically derived water demand patterns were subsequently used to calculate peak factors for different values of , varying from one second to one hour. The end-use model derived the water demand patterns by aggregating the synthesised end-use events of six residential indoor end-uses of water in terms of the water volume required, duration and the time of occurrence of each event. The probability distributions describing the end-use model parameters were derived from actual end-use measurements that had previously been collected in a noteworthy North-American end-use project (Mayer et al., 1999). The original comprehensive database, which included water measurements from both indoor and outdoor end-uses, was purchased for use in this project. A single execution of the end-use model resulted in the synthesised diurnal water demand pattern for a single household. The estimated water demand pattern for simultaneous water demand by groups of households was obtained by adding individual iterations of the end-use model, considering group sizes of between one and 2 000 households in the process. A total of 99 500 model executions were performed, which were statistically aggregated by applying the Monte Carlo method and forming 4 950 unique water demand scenarios representing 29 different household group sizes. For each of the 4 950 water demand scenarios, a set of peak factors was derived for eight selected values. The end-use model presented in this study yielded realistic indoor water demand estimations when compared to publications from literature. In agreement with existing knowledge, as expected, an inverse relationship was evident between the magnitude of the peak factors and . The peak factors across all time intervals were also found to be inversely related to the number of households, which agreed with other publications from literature. As the number of households increased, the degree to which the peak factor was affected by the time intervals decreased. This study explicitly demonstrated the effect of time intervals on peak factors. The results of this study could act as the basis for the derivation of a practical design guideline for estimating peak indoor flows in a WDS, and the work could be extended in future to include outdoor water demand and sensitivity to WDS pressure.
AFRIKAANSE OPSOMMING: Die verwagte water spitsaanvraag is ‘n belangrike oorweging in die ontwerp van ‘n waterverspreidingsnetwerk. Die mees algemene metode in Suid Afrika om spitsaanvraag te bereken is deur die gemiddelde wateraanvraag te vermeningvuldig met ‘n dimensielose spitsfaktor. ‘n Spitsfaktor is die verhouding tussen die maksimum watervloei tempo (wat verwys na die grootste volume water wat ontvang sal word tydens ‘n relatiewe kort tydsinterval, , uitgedruk as die gemiddelde volume per tyd eenheid), en die gemiddelde watervloei tempo gedurende ‘n verlengde tydsinterval. Die grootte van die spitsfaktor sal varieer vir ‘n gegewe daaglikse vloeipatroon, afhangende van die verkose waarde. Die beskikbare ontwerpsriglyne is onduidelik oor watter tydsintervalle meer geskik is vir die verskillende spitsfaktor toepassings. Daarom is dit belangrik om ‘n beter begrip te verkry ten opsigte van die effek van op die verkrygde spitsfaktor. ‘n Waarskynliksheidsgebaseerde eindverbruik model is opgestel om deel te vorm van hierdie studie, om daaglikse residensiële binnenshuise wateraanvraag patrone af te lei op ‘n temporale skaal van een sekonde. Die stogasties afgeleide wateraanvraag patrone is daarna gebruik om die verskeie spitsfaktore te bereken vir verskillende waardes van , wat varieer vanaf een sekonde tot een uur. Die eindverbruik model stel die daaglikse vloeipatroon van een huis saam deur die eindeverbruik gebeure van ses residensiële binnenshuise eindverbruike saam te voeg in terme van the vereiste water volume en die tyd van voorkoms van elke gebeurtenis. Die waarskynliksheids distribusie wat die eindverbruik model parameters omskryf is verkry van werklike gemete eindverbruik waardes, wat voorheen in ‘n beduidende Noord-Amerikaanse eindverbruik projek (Mayer et al. 1999) versamel is. Die oorspronklike en omvattende databasis, wat gemete waardes van binnenshuis en buite water verbruik ingesluit het, is aangekoop vir gebruik gedurende hierdie projek. ‘n Enkele uitvoering van die eindverbruik model stel gevolglik ‘n daaglikse wateraanvraag patroon saam vir ‘n elkele huishouding. Die wateraanvraag patroon vir gelyktydige water verbruik deur groepe huishoudings is verkry deur individuele iterasies van die eindverbruik model statisties bymekaar te tel met die Monte Carlo metode, terwyl groep groottes van tussen een en 2 000 huishoudings in die proses oorweeg is. ‘n Totaal van 99 500 model uitvoerings is gedoen, wat saamgevoeg is om 4 950 unieke watervraag scenarios voor te stel, wat verteenwoordigend is van 29 verskillende huishouding groep groottes. Vir elkeen van die 4 950 watervraag senarios, is ‘n stel spitsfaktore afgelei vir agt verkose waardes. Die eindverbruik model aangebied in hierdie studie lewer ‘n realistiese binnenshuise wateraanvraag skatting, wanneer dit vergelyk word met verslae in die literatuur. Ooreenkomstig met bestaande kennis is ‘n sterk inverse verhouding sigbaar tussen die grootte van die spitsfaktore en . Dit is ook gevind dat die spitsfaktore oor al die tydsintervalle ‘n inverse verband toon tot die aantal huishoudings, wat ooreenstemmend is met ander publikasies in die literatuur. Soos die aantal huishoudings toeneem, het die mate waartoe die spitsfaktor geaffekteer is deur die tydsintervalle afgeneem. Hierdie studie toon duidelik die effek van tydsintervalle op spitsfaktore. Die resultaat van hierdie studie kan dien as basis om praktiese ontwerpsriglyne te verkry in die skatting van binnenshuise spitsvloei in ‘n waterverspreidingsnetwerk, gegewe dat die werk in die toekoms uitgebrei kan word om ook buitenshuise waterverbruik in te sluit, asook sensitiwiteit tot druk in die waterverspreidingsnetwerk.

APA, Harvard, Vancouver, ISO, and other styles

3

Zaman, Bushra. "Remotely Sensed Data Assimilation Technique to Develop Machine Learning Models for Use in Water Management." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/584.

Full text

Abstract:

Increasing population and water conflicts are making water management one of the most important issues of the present world. It has become absolutely necessary to find ways to manage water more efficiently. Technological advancement has introduced various techniques for data acquisition and analysis, and these tools can be used to address some of the critical issues that challenge water resource management. This research used learning machine techniques and information acquired through remote sensing, to solve problems related to soil moisture estimation and crop identification on large spatial scales. In this dissertation, solutions were proposed in three problem areas that can be important in the decision making process related to water management in irrigated systems. A data assimilation technique was used to build a learning machine model that generated soil moisture estimates commensurate with the scale of the data. The research was taken further by developing a multivariate machine learning algorithm to predict root zone soil moisture both in space and time. Further, a model was developed for supervised classification of multi-spectral reflectance data using a multi-class machine learning algorithm. The procedure was designed for classifying crops but the model is data dependent and can be used with other datasets and hence can be applied to other landcover classification problems. The dissertation compared the performance of relevance vector and the support vector machines in estimating soil moisture. A multivariate relevance vector machine algorithm was tested in the spatio-temporal prediction of soil moisture, and the multi-class relevance vector machine model was used for classifying different crop types. It was concluded that the classification scheme may uncover important data patterns contributing greatly to knowledge bases, and to scientific and medical research. The results for the soil moisture models would give a rough idea to farmers/irrigators about the moisture status of their fields and also about the productivity. The models are part of the framework which is devised in an attempt to provide tools to support irrigation system operational decisions. This information could help in the overall improvement of agricultural water management practices for large irrigation systems. Conclusions were reached based on the performance of these machines in estimating soil moisture using remotely sensed data, forecasting spatial and temporal variation of soil moisture and data classification. These solutions provide a new perspective to problem–solving techniques by introducing new methods that have never been previously attempted.

APA, Harvard, Vancouver, ISO, and other styles

4

Norman, Laura Margaret. "Modeling Land Use Change and Associate Water Quality Impacts in the Ambos Nogales Watershed, US-Mexico Border." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1427%5F1%5Fm.pdf&type=application/pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Hager, Christian Harding. "Ichthyofaunal and dietary analysis of sympatric piscivores in a Chesapeake Bay littoral zone: Including bioenergetic models of growth and diel temperature sanctuary use." W&M ScholarWorks, 2004. https://scholarworks.wm.edu/etd/1539616682.

Full text

Abstract:

The first section of this dissertation describes the ichthyofaunal community of a mesohaline Chesapeake Bay April--November. Fish assemblages were sampled using two seine gears, a small seine that sampled 352 m 2 and a 914m haul-seine that sampled 144,473 m2. The small seine collected 32 finfish species. The larger gear captured 31 finfish species, including 17 that were not sampled by small gear. Sampled diversity was greater but density estimates were similar to those determined previously by other investigators using flume-net, drop-ring, and otter trawl techniques. Nocturnal abundance of larger fishes far exceeded daylight. Fish abundance and size distribution varied seasonally in both gears. The second section describes the littoral diet composition of striped bass (Morone saxatilis ), bluefish (Pomatomus saltatrix), and weakfish (Cynoscion regalis). These species were the most abundant piscivores sampled in the littoral zone. as in previous Chesapeake Bay diet studies the importance of pelagic prey increased with predator size, however, littoral diets evidenced greater dietary diversity and dependence on crustacean prey items. The third section consists of bioenergetic models that predict piscivore growth based on estimated nocturnal consumption and test energetic consequences of diel thermal refugia. Bluefish and weakfish were predicted to achieve better growth rates than those evidenced by field samples of aged fishes collected from across random Chesapeake habitats. Models predict that striped bass experience declining condition during warm water periods due to physiological stresses and poor prey acquisition. Theoretical diel relocation models illustrated how important species and age specific metabolic restrictions due to physical parameters are to fish health. Findings suggest that habitat specific physical dynamics may be as important as prey provision in determination of and spatial assessments of essential fish habitats.

APA, Harvard, Vancouver, ISO, and other styles

6

Boyd, Timothy David. "The Novel Use of Recombinant Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) to Reverse Cerebral Amyloidosis and Cognitive Impairment in Alzheimer’s Disease Mouse Models: Insights from the Investigation of Rheumatoid Arthritis as a Negative Risk Factor for Alzheimer’s Disease." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3571.

Full text

Abstract:

For many years, it has been known that Rheumatoid arthritis (RA) is a negative risk factor for the development of Alzheimer’s disease (AD). It has been commonly assumed that RA patients’ usage of non-steroidal anti-inflammatory drugs (NSAIDs) have helped prevent the onset and progression of AD pathogenesis. Furthermore, experiments in animal models of Alzheimer’s disease have looked to inhibit inflammation, and have demonstrated some efficacy against AD-like pathology in these models. Thus many NSAID clinical trials have been performed over the years, but all have proven unsuccessful in AD patients. This suggests that intrinsic factors within RA pathogenesis itself may underlie RA’s protective effect. My dissertation research goal was to investigate this inverse relationship between RA and AD, in order to more precisely pinpoint critical events in AD pathogenesis toward developing therapeutic strategies against AD. It seemed improbable that any secreted factors, produced in RA pathogenesis, could maintain high enough concentrations in the circulatory system to cross the blood brain barrier and inhibit AD pathogenesis, without affecting all other organ systems. It did seem possible that the leukocyte populations induced in RA, could traverse the circulatory system, extravasate into the brain parenchyma, and impede or reverse AD pathogenesis. We thus investigated the colony-stimulating factors, which are up-regulated in RA and which induce most of RA’s leukocytosis, on the pathology and behavior of transgenic AD mice. We found that G-CSF and more significantly, GM-CSF, reduced amyloidosis throughout the treated brain hemisphere one week following bolus intrahippocampal administration into AD mice. We then found that 20 days of subcutaneous injections of GM-CSF (the most amyloid-reducing CSF in the bolus experiment) significantly reduced brain amyloidosis and completely reversed cognitive impairment in aged cognitively-impaired AD mice, while increasing hippocampal synaptic area and microglial density. These findings, along with two decades of accrued safety data using Leukine, the recombinant human GM-CSF analogue, in elderly leukopenic patients, suggested that Leukine should be tested as a treatment to reverse cerebral amyloid pathology and cognitive impairment in AD patients. It was also implied that age-related depressed hematopoiesis may contribute to AD pathogenesis.

APA, Harvard, Vancouver, ISO, and other styles

7

Dlamini, Musa V. "Short-Term Water Use Dynamics in Drainage Lysimeters." DigitalCommons@USU, 2003. https://digitalcommons.usu.edu/etd/5877.

Full text

Abstract:

Turfgrass water use (seasonal turfET) and crop coefficients were determined and a mathematical soil-water balance model for non-weighing drainage lysimeters, which simulates the occurrence (timing and amount) of drainage, was developed. Pairs of non-weighing drainage lysimeters were used to determine crop coefficients for turfgrass in four locations in the state of Utah: Logan Golf and Country Club, Murray Golf Course, Brigham Young University (Spanish Fork) Experiment Farm, and Sunbrook Golf Course (St. George). Daily weather data including air temperature, relative humidity, average wind travel, total solar radiation, precipitation, and average soil temperature were collected with an electronic weather station at each site. Daily precipitation was measured in three sites throughout the season: Murray, Spanish Fork, and Sunbrook. At Logan Golf and Country Club, precipitation was measured to November 10,2002. Water use (averages of two lysimeters) during the growing season varied from 684 to 732 mm for three years (2000- 2002) for the mid-April through late-October observation period at Logan Golf Course; 699 mm for May through October at Murray; 469 mm at Spanish Fork; and 896 mm for late-February through early November at Sunbrook, for 2002 growing season. Calculated seasonal Etr using the 82 Kimberly Penman equation with a 1 00-miles-per-day wind travel limit varied from 1166 to 1229 mm at Logan Golf and Country Club, 1067 mm at Murray, 839 mm at Spanish Fork, and 1574 mm at Sunbrook. Seasonal Etr calculated using the PM ASCE std Etr equation was greater than the 82 Kimberly Peru11an . Seasonal Eto calculated using the FAO#56 Eto equation was less than both the 82 Kimberly Penman and the PM ASCE std Etr equations. Calculated crop coefficients (as a ratio of measured crop water use and calculated potential evapotranspiration) based on alfalfa reference evapotranspiration with the 1982 Kimberly-Penman equation averaged 0.58 for the three years at Logan. Seasonal averages varied from 0.57 to 0.60. Seasonal crop coefficients (2002) were 0.57 for Logan, Spanish Fork, and Sunbrook, and 0.65 for Murray. Short-period crop coefficients also varied within a given season. Short-term crop coefficients derived from a time of wetting and drainage experiment averaged 0.55 at Logan, 0.56 at Murray, 0.60 at Spanish Fork, and 0.56 at Sunbrook.

APA, Harvard, Vancouver, ISO, and other styles

8

Kane, Dellwyn. "Hydrograph separation using end member mixing models in the Oona Water river catchment, Co Tyrone." Thesis, University of Ulster, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529518.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Smith, Kimberly C. (Kimberly Carolyn). "Evaluating PC-based water quality models as tools for land use planning." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/70200.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Meeuwig, Jessica Jane. "All water is wet : predicting eutrophication in lakes and estuaries." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35918.

Full text

Abstract:

Coastal eutrophication, defined as an increase in algal biomass (as chlorophyll (Chl)) is of increasing international concern. Although coastal eutrophication will likely increase as coastal populations grow, few models exist to support its management. Lake eutrophication has also long been recognized as an important environmental concern. However, effective lake eutrophication management exists, supported by regression and mass-balance models. Traditionally, these "Vollenweider" models link land-use to Chl via total phosphorus (TP), the nutrient considered to be limiting Chl. However, based on a data set of 63 lakes, Chl was more accurately predicted by models based on land-use than by those based on TP. This result provided the rationale to build Chl:land-use models for estuaries where the Chl:nutrient relations are unclear. Chl:land-use models were developed for 15 estuaries in PEI, 19 estuaries in Finland and 26 US estuaries. Land-use models predicted Chl more accurately than TP in the US estuaries and in some of the Finnish estuaries. In the Finnish estuaries, Chl was best predicted by a land-use model in estuaries dominated by nonpoint source loading whereas Chl was most accurately predicted by the Vollenweider approach in estuaries dominated by point-source loading. In the PEI estuaries, the accuracy of the land-use model was comparable to the accuracy of the TP model. The PEI estuaries had much lower yields of Chl per unit nutrient than lakes suggesting differences among systems. This Chl deficit (expected-observed Chl) was accounted for by herbivory and turbidity, neither of which factors are exclusive to estuaries. The comparison of Chl response to nutrients and land-use across lakes and estuaries demonstrated no systematic differences as a function of tidal energy, openness or salinity. The regression models based on the combined data accurately predicted Chl as a function of TP and percentage of the catchment forested and mean depth. These results sug

APA, Harvard, Vancouver, ISO, and other styles

11

Rui, Li. "The use of treated effluent for agricultural irrigation in the Bottelary River area: Effluent quality, farmers perception and potential extent." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=init_1918_1177917293.

Full text

Abstract:

The Bottelary River area is located in a Mediterranean climate region, where the agricultural sector plays an important role. During the dry summer season, there is not enough precipitation to meet the agricultural irrigation requirements. Some farmers extract river water which is practically the final treated effluent from the Scottsdene Wastewater Treatment Works to irrigate crops. This research investigated the use of treated effluent for agricultural irrigation in this area, particularly focused on the effluent quality, farmers perception, and the potential extent.

APA, Harvard, Vancouver, ISO, and other styles

12

Chingombe, Wisemen. "Effects of land-cover - land-use on water quality within the Kuils - Eerste River catchment." Thesis, University of Western Cape, 2012. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_5893_1373463134.

Full text

Abstract:

The most significant human impacts on the hydrological system are due to land-use change. The conversion of land to agricultural, mining, industrial, or residential uses significantly alters the hydrological characteristics of the land surface and modifies pathways and rates of water flow. If this occurs over large or critical areas of a catchment, it can have significant short and long-term impacts, on the quality of water. While there are methods available to quantify the pollutants in surface water, methods of linking non-point source pollution to water quality at catchment scale are lacking. Therefore, the research presented in this thesis investigated modelling techniques to estimate the effect of land-cover type on water quality. The main goal of the study was to contribute towards improving the understanding of how different land-covers in an urbanizing catchment affect surface water quality. The aim of the research presented in this thesis was to explain how the quality of surface runoff varies on different land-cover types and to provide guidelines for minimizing water pollution that may be occurring in the Kuils-Eerste River catchment. The research objectives were
(1) to establish types and spatial distribution of land-cover types within the Kuils-Eerste River catchment, (2) to establish water quality characteristics of surface runoff from specific land-cover types at the experimental plot level, (3) to establish the contribution of each land-cover type to pollutant loads at the catchment scale. Land-cover characteristics and water quality were investigated using GIS and Remote Sensing tools. The application of these tools resulted in the development of a land-cover map with 36 land classifications covering the whole catchment. Land-cover in the catchment is predominantly agricultural with vineyards and grassland covering the northern section of the catchment. Vineyards occupy over 35% of the total area followed by fynbos (indigenous vegetation) (12.5 %), open hard rock area (5.8 %), riparian forest (5.2 %), mountain forest

(5 %), dense scrub (4.4 %), and improved grassland (3.6 %). The residential area covers about 14 %. Roads cover 3.4 % of the total area. Surface runoff is responsible for the transportation of large quantities of pollutants that affect the quality of water in the Kuils-Eerste River catchment. The different land-cover types and the distribution and concentration levels of the pollutants are not uniform. Experimental work was conducted at plot scale to understand whether land-cover types differed in their contributions to the concentration of water quality attributes emerging from them. Four plots each with a length of 10 m to 12 m and 5 m width were set up. Plot I was set up on open grassland, Plot II represented the vineyards, Plot III covered the mountain forests, and Plot IV represented the fynbos land-cover. Soil samples analyzed from the experimental plots fell in the category of sandy soil (Sa) with the top layer of Plot IV (fynbos) having loamy sand (LmSa). The soil particle sizes range between fine sand (59.1 % and 78.9 %) to coarse sand (between 7 % and 22 %). The content of clay and silt was between 0.2 % and 2.4 %. Medium sand was between 10.7 % and 17.6 %. In terms of vertical distribution of the particle sizes, a general decrease with respect to the size of particles was noted from the top layer (15 cm) to the bottom layer (30 cm) for all categories of the particle sizes. There was variation in particle size with depth and location within the experimental plots.Two primary methods of collecting water samples were used
grab sampling and composite sampling. The quality of water as represented by the samples collected during storm events during the rainfall season of 2006 and 2007 was
used to establish
water quality characteristics for the different land-cover types. The concentration of total average suspended solids was highest in the following land-cover types, cemeteries (5.06 mg L^-1), arterial roads/main roads (3.94 mg L^-1), low density residential informal squatter camps (3.21 mg L^-1) and medium density residential informal townships (3.21 mg L^-1). Chloride concentrations were high on the following land-cover types, recreation grass/ golf course (2.61 mg L^-1), open area/barren land (1.59 mg L^-1), and improved grassland/vegetation crop (1.57 mg L^-1). The event mean concentration (EMC) values for NO₃-N were high on commercial mercantile (6 mg L^-1) and water channel (5 mg L^-1). The total phosphorus concentration mean values recorded high values on improved grassland/vegetation crop (3.78 mg L^-1), medium density residential informal townships (3mgL^-1) and low density residential informal squatter camps (3 mg L^-1). Surface runoff may also contribute soil particles into rivers during rainfall events, particularly from areas of disturbed soil, for example areas where market gardening is taking place. The study found that different land cover types contributed differently to nonpoint source pollution. A GIS model was used to estimate the diffuse pollution of five pollutants (chloride, phosphorus, TSS, nitrogen and NO₃-N) in response to land cover variation using water quality data. The GIS model linked land cover information to diffuse nutrient signatures in response to surface runoff using the Curve Number method and EMC data were developed. Two models (RINSPE and N-SPECT) were used to estimate nonpoint source pollution using various GIS databases. The outputs from the GIS-based model were compared with recommended water quality standards. It was found that the RINSPE model gave accurate results in cases where NPS pollution dominate the total pollutant inputs over a given land cover type. However, the N-SPECT model simulations were too uncertain in cases where there were large numbers of land cover types with diverse NPS pollution load. All land-cover types with concentration values above the recommended national water quality standard were considered as areas that needed measures to mitigate the adverse effects of nonpoint pollution. The expansion of urban areas and agricultural land has a direct effect on land cover types within the catchment. The land cover changes have adverse effect which has a potential to contribute to pollution.

APA, Harvard, Vancouver, ISO, and other styles

13

James, Ryan. "Agent-Based Model to Manage Household Water Use Through Social-Environmental Strategies of Encouragement and Peer Pressure." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7581.

Full text

Abstract:

Inelastic price responses, demand hardening, and poor public awareness reduce the effectiveness of demand side strategies on water savings. This project quantified phycological household’s factors of attitudes, peer support, opportunities on water conservation with two social-environmental management strategies of encouragement and peer pressure. An agent-based model was populated with data for Logan, Utah using surveys, municipal billing, aerial imagery, weather monitoring stations, and flow, frequency, and durations of appliance use data. Results indicated those households with higher attitudes, peer support and opportunities saved the most water while peer pressure saved more than encouragement when using small and diverse social networks that could better regulate the behavior of outlier households within the network. Combined peer pressure and encouragement saved the most water as each strategy complimented one other. Managers can use results to identify and target large use households. Managers should recommend opportunities to conserve water through monthly bills and provide platforms for households to share their water use stories and information with each other.

APA, Harvard, Vancouver, ISO, and other styles

14

Zalewsky, Brian J. "Use of the Water Erosion Prediction Project (WEPP) Model to Predict Road Surface Erosion in Mountain Rangeland Areas." DigitalCommons@USU, 1998. https://digitalcommons.usu.edu/etd/3655.

Full text

Abstract:

A significant source of sediment in many watersheds is that associated with the layout, construction, and maintenance of roadways. Much work has been done in more mesic forested environments with little or none in semiarid systems. Acc urate estimation of runoff and sediment yield from native surfaced roads located in semiarid mountainous ecosystems is important to both private and public regulatory agencies. The Watershed Erosion Prediction Project (WEPP) model represents the most current erosion prediction technology. WEPP has been applied to the problems of logging road erosion in more mesic forests but has not been tested or evaluated on roadways located in semiarid mountainous ecosystems. Six rainfall simulation experiments were conducted to measure runoff and sediment yield off three separate plots located on Tickville Road, located on Camp W.G. Williams, a National Guard Training Center in Utah . These data were compared with runoff and erosion estimates produced by the WEPP model. WEPP cropland and rangeland erodibility equations were used to predict rill erodibility (Kr), interrill erodibility (Ki), and critical shear (TAUc). These were tested for their effectiveness in predicting road erodibilities in these environments. A sensitivity analysis was performed on those parameters that were suspected of having a substantial impact on model output and accuracy. There was an excellent correlation between predicted and observed total runoff volumes for all simulations (R2= 0.96). The differences were greater than 10% only for plot 2 wet; otherwise, the average difference for all six simulations was 4.9%. When using Kr, K.i , and TAUc as predicted by rangeland methods, predicted sediment yields differed from those measured, on average, by 82%. Predicted sediment yields differed by only 22% compared to calculated sediment yields, when using the cropland erodibility equations to predict Kr, K.i , and TAUc. A sensitivity analysis showed that percent slope, slope length, days since last tillage, and ridge roughness all had a significant impact on WEPP predicted sediment yields. Results show the effectiveness of the WEPP model in predicting runoff and erosion off native surfaced roads in these semiarid mountainous regions.

APA, Harvard, Vancouver, ISO, and other styles

15

Mohamed, Shehaamah. "Competing water user sectors under a transformed South African water law: the role of local government, with a case study on the City of Cape Town Municipality." Thesis, University of the Western Cape, 2003. http://etd.uwc.ac.za/index.php?module=etd&amp.

Full text

Abstract:

This thesis attempted to examine the enabling conditions of existing South African water law and its implementation by the appropriate authorities. The Cape Town Municipality's management over water supply and services is included in this study. The research attempted to expose any shortcomings that might be prevalent in the new water law. The water allocation mechanism of the transformed water legislation and the water demands within various competing water user sectors of the community, such as those pertaining to agriculture and industry, was also explored.

APA, Harvard, Vancouver, ISO, and other styles

16

Larrubia, Caio Bertolo. "Método AHP como instrumento de apoio à decisão para a manutenção da qualidade da água do reservatório de Ilha Solteira /." Ilha Solteira : [s.n.], 2010. http://hdl.handle.net/11449/98071.

Full text

Abstract:

Resumo: O reservatório da Usina Hidrelétrica Ilha Solteira localiza-se entre os estados de São Paulo, Mato Grosso do Sul, Minas Gerais e Goiás inserindo-se na Bacia Hidrográfica do Rio Paraná. Este reservatório foi construído com o objetivo de geração de energia, porém, como geralmente ocorre com a maioria dos reservatórios, passou a ser utilizado para múltiplas finalidades. Dentre os usos se destacam o transporte hidroviário, a irrigação, a aquicultura e o lazer. Devido à boa qualidade de suas águas, apresenta uma forte tendência ao aumento das utilizações deste recurso. Considerando que alguns aproveitamentos resultam em impactos e consequentes conflitos relacionados aos interesses de usos do recurso, é de suma importância o desenvolvimento de medidas disciplinadoras que visem à manutenção da qualidade da água. Nesse sentido, a presente proposta objetivou estabelecer uma hierarquia dos principais usos do reservatório considerando critérios econômicos, sociais, operacionais e a qualidade da água. Para tanto, adotou-se um Modelo Multicritério de Apoio à Decisão, onde, com a utilização do método Analytic Hierarchy Process (AHP), as modalidades de uso do reservatório foram priorizadas. De acordo com o constatado no presente estudo, o segmento de recreação e turismo apresentou o melhor desempenho nos critérios avaliados, sendo considerado como prioridade global para a utilização da água do reservatório de Ilha Solteira e de seus afluentes. O uso dos recursos hídricos para irrigação se mostrou interessante, sendo que foi apontado como prioridade em alguns municípios. A aquicultura aparece em terceiro lugar na ordem de prioridade, se destacando tanto em projetos da iniciativa privada como em projetos com investimentos públicos. A região apresentou um baixo uso dos recursos hídricos para o transporte hidroviário, sendo este segmento quase uma exclusividade... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Ilha Solteira reservoir is located between the States of São Paulo, Mato Grosso do Sul, Minas Gerais and Goias, inserted in Paraná's river basin. This reservoir was built with the purpose of power generation, but as it usually happens with most reservoirs, it began to be used for multiple purposes. Among the various uses of the reservoir can be highlighted the navigation, the irrigation, the aquaculture and the recreation. Due to the high quality of its waters, there's a strong intent on increasing the use of this resource, being that some uses result in significant impact and therefore, conflicts of interest arise. It is then of utmost importance the creation of disciplinary measures targeted on maintaining water quality. In that sense, this proposal aims to establish a hierarchy of the main uses of the reservoir, considering the criteria economical, social, operational and the quality of the water. To that end, was adapted a Multi-Criteria Decision Support model, where, using the method of Analytic Hierarchy Process (AHP), the uses of the reservoir were prioritized. According to the results of this study, the segment of recreation and tourism showed the best performance on the evaluated criteria and was defined as the global priority concerning the water usage of the reservoir of Ilha Solteira and of their tributaries. The use of water resources for irrigation proved to be interesting, and it was appointed as a priority in some cities. The aquaculture appears in third place in the priority order, standing out so much in projects of the private initiative such as in projects with public investments. The region presented low use of water resources for waterborne transport, being that segment almost exclusiveness of the São Simão-GO city. The usage of the water to supply showed little expression on the cities in the region, however deserves attention for the volume of sewage... (Complete abstract click electronic access below)
Orientador: Milton Dall'Aglio Sobrinho
Coorientador: Maurício Augusto Leite
Banca: José Augusto de Lollo
Banca: Evaldo Luiz Gaeta Espíndola
Mestre

APA, Harvard, Vancouver, ISO, and other styles

17

McHugh, Kathleen M. "Western water law and the stream-aquifer system and how models are used to determine permitting and compliance of rules governing ground and surface water interaction." Thesis, The University of Arizona, 2003. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0234_sip1_w.pdf&type=application/pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Risbey, James S. (James Sydney). "On the use of climate models to assess the impacts of regional climate change on water resources." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/57652.

Full text

Abstract:

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1994.
Includes bibliographical references (p. 207-213).
by James Sydney Risbey.
Ph.D.

APA, Harvard, Vancouver, ISO, and other styles

19

Krause, Colin William. "Evaluation and Use of Stream Temperature Prediction Models for Instream Flow and Fish Habitat Management." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/31229.

Full text

Abstract:

The SNTEMP (U.S. Fish and Wildlife Service), QUAL2E (U.S. Environmental Protection Agency), and RQUAL (Tennessee Valley Authority) stream temperature prediction models were evaluated. All models had high predictive ability with the majority of predictions, >80% for Back Creek (Roanoke County, VA) and >90% for the Smith River tailwater (SRT) (Patrick County, VA), within 3Â°C of the measured water temperature. Sensitivity of model input parameters was found to differ between model, stream system, and season. The most sensitive of assessed parameters, dependent on model and stream, were lateral inflow, starting-water, air, and wet-bulb temperature. All three models predicted well, therefore, selecting a model to assess alternative water management scenarios was based on model capabilities. The RQUAL model, used to predict SRT temperatures under alternative hydropower release regimes, illustrated potential thermal habitat improvement for brown trout (Salmo trutta) compared to existing conditions. A 7-day/week morning 1 hr release was determined to best concurrently increase occurrence of brown trout optimal growth temperatures (+10.2% mean), decrease 21Â°C (state standard) exceedances (99% prevention), and decrease hourly changes in temperature (-1.6Â°C mean) compared to existing thermal conditions. The SNTEMP model was used to assess thermal habitat under flow, shade, and channel width changes occurring from future urbanization within the Back Creek watershed. Predictions reveal that additional urban development could limit thermal habitat for present fish species by elevating summer mean daily temperature up to 1Â°C and cause 31Â°C (state standard) exceedances compared to existing conditions. Temperature impacts were lessened by single rather than cumulative changes suggesting mitigation measures may maintain suitable thermal habitat.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

20

Watson, Eric Craig. "Use of Distance Weighted Metrics to Investigate Landscape-Stream Temperature Relationships Across Different Temporal Scales." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/3117.

Full text

Abstract:

Stream ecosystems have experienced significant negative impacts from land use, resource exploitation, and urban development. Statistical models allow researchers to explore the relationships between these landscape variables and stream conditions. Weighting the relevant landscape variables based on hydrologically defined distances offers a potential method of increasing the predictive capacity of statistical models. Using observations from three grouped watersheds in the Portland Metro Area (n=66), I have explored the use of three different weighting schemes against the standard method of taking an areal average. These four different model groups were applied to four stream temperature metrics: mean seven-day moving average maximum daily temperature (Mean7dTmax), number of days exceeding 17.8 °C (Tmax7d>17.8), mean daily range in stream temperature (Range_DTR), and the coefficient of variation in maximum daily temperature (CV_Tmax). These metrics were quantified for the 2011 dry season. The strength of these model groups were also examined at a monthly basis for each of the four months within the dry season. The results demonstrate mixed effectiveness of the weighting schemes, dependent on both the stream temperature metric being predicted as well as the time scale under investigation. Models for Mean7dTmax showed no benefit from the inclusion of distance weighted metrics, while models for Range_DTR consistently improved using distance weighted explanatory variables. Trends in the models for 7dTmax>17.8 and CV_Tmax varied based on temporal scale. Additionally, all model groups demonstrated greater explanatory power in early summer months than in late summer months.

APA, Harvard, Vancouver, ISO, and other styles

21

Son, Kyongho. "Improving model structure and reducing parameter uncertainty in conceptual water balance models with the use of auxiliary data." University of Western Australia. School of Environmental Systems Engineering, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0094.

Full text

Abstract:

[Truncated abstract] The use of uncertainty analysis is gaining considerable attention in catchment hydrological modeling. In particular, the choice of an appropriate model structure, the identifiability of parameter values, and the reduction of model predictive uncertainty are deemed as essential elements of hydrological modelling. The chosen model structure must be parsimonious, and the parameters used must either be derivable from field measured data or inferred unambiguously from analysis of catchment response data. In this thesis, a long-term water balance model for the Susannah Brook catchment in Western Australia has been pursued using the ?downward approach?, which is a systematic approach to determine the model with the minimum level of complexity, with parameter values that in theory are derivable from existing physiographic data relating to the catchment. Through the analysis of the rainfall-runoff response at different timescales, and the exploration of the climate, soil and vegetation controls on the water balance response, an initial model structure was formulated, and a priori model parameter values estimated. Further investigation with the use of auxiliary data such as deuterium concentration in the stream and groundwater level data exposed inadequacies in the model structure. Two more model structures were then proposed and investigated through formulating alternative hypotheses regarding the underlying causes of observed variability, including those associated with the absence of a contribution of deep groundwater flow to the streamflow, which was indicated by deuterium concentration and internal dynamics characterized by the observed groundwater levels. ... These differences are due to differences in the time delay between rainfall and recharge between upland and riparian regions. The ages of water recharging the groundwater and discharging from the catchment were estimated by assuming a piston flow mechanism. In the deeper, upland soils, the age of recharging water was considerably larger than the unsaturated zone delay would suggest; a recharge response 16 days after an infiltration event may involve water as much as 160 days old. On the other hand, the delay and the age of recharging water were much lower in the shallow riparian zone. Where the upland zone contributes significantly to discharge, the predicted difference between the rainfall-discharge response time and the average age of discharging water can be significant.

APA, Harvard, Vancouver, ISO, and other styles

22

Lengwe, Egret Chanda. "An investigation into the use of existing public-private partnerships models in the Zambian water and sanitation sector." Thesis, Heriot-Watt University, 2014. http://hdl.handle.net/10399/2734.

Full text

Abstract:

A PPP concept has become one of the preferred strategic option used world over in the delivery of public services though still considered as a developing concept. In this study, it has been used as a tool for value addition and enhancement of service delivery as opposed to it being a financing strategy. The aim of the research was “to investigate into the use of existing PPP Models in the Zambian Water and Sanitation Sector (WSS) for increased effectiveness.” A quantitative research methodology was used to investigate the extent to which existing PPP Models could increase effectiveness through dimensions of cost, time and quality. Descriptive statistics and content analysis methods were used to analyse the data. Results indicate that all the existing PPP Models can be used to increase effectiveness of dimensions of cost, time and quality though at different levels of impact based on mean values. A Conceptual Beta Model has been developed based on the adopted existing PPP Models, the independent factors of cost, time and quality and peripheral aspects that arose from the interview survey. The sample was drawn from existing water utility companies, councils and other related stakeholders in Zambia. The data collection included literature review, questionnaires and follow up semi-structured interviews with PPP experts in Zambia. A Conceptual Alpha Model was first developed and subjected to further research prior to developing a Conceptual Beta Model. The Conceptual Beta Model aims to provide a basis for existing PPP Model increased effectiveness in the Water and Sanitation Sector and has been proposed for operationalization. The study provides a greater understanding of how existing PPP Models can be used to increase effectiveness through dimensions of cost, time and quality thereby providing tangible benefits in as far as the provision of water and sanitation services in Zambia is concerned.

APA, Harvard, Vancouver, ISO, and other styles

23

Ragaee, Sanaa. "Physicochemical and structural characteristics of water-extractable arabinoxylan from rye lines varying in extract viscosity and its relationship to end-use characteristics." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ63915.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Anputhas, Markandu. "Simulating land use change for assessing future dynamics of land and water resources." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/56181.

Full text

Abstract:

Models of land use change fall into two broad categories: pattern based and process based. This thesis focuses on pattern based land use change models, expanding our understanding of these models in three important ways. First, it is demonstrated that some driving variables do not have a smooth impact on the land use transition process. Our example variable is access to water. Land managers with access to piped water do not have any need for surface or groundwater. For variables like this, a model needs to change the way that driving variables are represented. The second important result is that including a variable which captures spatial correlation between land use types significantly increases the explanatory power of the prediction model. A major weakness of pattern based land use models is their inability to model interactions between neighbouring land parcels; the method proposed in this study can be an alternative to account for spatial neighbourhood association. These innovations are applied using the CLUE-S (Conversion of Land Use and its Effects at Small regional extent) system to the Deep Creek watershed in the Southern Interior of British Columbia. The results highlight the challenge of balancing the protection of agricultural land and conserving forest and natural areas when population and economic growth are inevitable. The results also demonstrate the implications of land use change on existing land use policies. The calibrated model was validated using remote sensing data. A series of discriminant functions were estimated for each land use type in the recent period and these functions were then used to classify. The calibrated model was run in reverse, back to the generated land use classification, and results compared. Fit was reasonable with error rates falling below ten percent when radii beyond 2.5 km were considered. Another important contribution is demonstrating the importance of modelling dynamic variables. Some important drivers are changing continuously and others depend on land use change itself. Failure to update these variables will bias model forecasts. Spatial neighbourhood association, an endogenous variable governed by land use change itself, is again used as the example dynamic variable. The study demonstrates the importance of updating all associated information.
Graduate Studies, College of (Okanagan)
Graduate

APA, Harvard, Vancouver, ISO, and other styles

25

Fatnasare, Ike S. "A study of the effect of water-pick up of UV curable offset ink on its curing time and its end use properties /." Online version of thesis, 1993. http://hdl.handle.net/1850/11169.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Kumamaru, Koji. "A comparative assessment of communal water supply and self supply models for sustainable rural water supplies : a case study of Luapula, Zambia." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9061.

Full text

Abstract:

Over the last couple of decades, a significant amount of research has been carried out on rural water supplies in developing countries, and have identified the fact that the communal water supply model is not sustainable everywhere, especially in sparsely populated rural areas; factors obstructing sustainability include lack of spare parts, management systems and private/public capacity. Despite their enormous contribution to the water sector, the extant studies stay within the subsidized communal water supply and capacity building, post construction support or management system. In other words, very few studies have been done into household (private) level water supply. The Self Supply model is an approach which provides support to households/communities to complement their efforts and accelerate sustainable access to safe water incrementally through improvement to traditional water sources (hand dug wells) by putting in their own investment. The Self Supply model may give significant benefits for sustainable safe water supplies, especially in sparsely populated rural areas, in comparison with the communal water supply though to date there has been little monitoring and systematic analysis of what impact these changes have made at the grassroots level. The standpoint of this study is pragmatic, and herein, mixing quantitative and qualitative methods was justified in order to design the research methodologies. The research was conducted in the Luapula Province of Zambia using a concurrent triangulation strategy to offset the weakness inherent within one method with the strengths of the other. The data was collected through inventory and sanitary surveys, water quality testing, household surveys, document analyses, focus group discussions and key informant interviews to determine the most appropriate water supply model for safe, accessible, sustainable, cost-effective and acceptable water supplies for households in sparsely populated rural areas of Zambia. The principal argument of this study is that reliance only on a communal water supply model limits the achievement of increased sustainable access to a safe water supply; hence a Self Supply model is needed which does not compete with the communal models but works alongside them in sparsely populated rural areas of developing countries for the purpose of increasing access and achieving sustainability. It was strongly defended by the overall findings that a Self Supply model could significantly reduce the faecal contamination risk in water quality and deliver a higher per capita water use and better convenience of access than the communal model; however its reliability with respect to the water source drying up needs to be monitored. Further, this does not mean that the communal model is not sustainable anywhere, rather that it is important to build blocks for a sustainable environment to access safe water in a symbiotic way between the communal and Self Supply models under the condition that the government and NGOs/external support agencies overcome the temptation to provide a water supply to rural dwellers as a giveaway social service.

APA, Harvard, Vancouver, ISO, and other styles

27

Sithole, Pinimidzai. "A Comparative Study of Rural Water Governance in the Limpopo Basin." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1684_1319187072.

Full text

Abstract:

In this thesis I examine and explore whether and if Integrated Water Resources Management (IWRM) inspired water reforms respond to- and address the diverse realities of women and men in informal (and formal) rural economies of Sekororo, South Africa and Ward 17 in Gwanda, Zimbabwe which are both in the Limpopo basin. South Africa and Zimbabwe, like other southern African countries, embarked on IWRMinspired water reforms, culminating in the promulgation of the National Water Acts in 1998, four years after the attainment of South Africaâs democracy in 1994 and 18 years after Zimbabwe attained independence in 1980. I argue that the adoption of IWRM, which emphasises second generation water issues such as demand management, water quality, environmental flow requirements etc, and not the development of water infrastructure, begs the question whether such reforms can make a meaningful contribution to the development agenda in countries where, during apartheid and colonialism, the water rights (among other rights) of millions of blacks were compromised because of unjust legislation and skewed underinvestment in water infrastructure

APA, Harvard, Vancouver, ISO, and other styles

28

Marsà, Salvany Alícia. "Assessing the carcinogenic risk of water disinfection by-products. Use of in vitro models to evaluate halonitromethanes and haloacetic acids." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/458681.

Full text

Abstract:

Els subproductes de desinfecció de l’aigua són tots aquells productes resultants de reaccions químiques entre la matèria orgànica i inorgànica de l’aigua i els agents químics utilitzats en la seva desinfecció. Fins aquest moment, s’han identificat més de 600 classes de DBP en aigües tractades arreu del món. Estudis epidemiològics mostren una forta relació entre la presència d’aquests productes i la incidència de càncer, però fins ara no s’han pogut identificar les espècies responsables d’aquests efectes. La majoria de protocols in vitro utilitzats per establir la genotoxicitat i carcinogenicitat de cada classe de DBP s’han basat en exposicions agudes a concentracions relativament altes d’aquestes espècies químiques, seguits d’una extrapolació a concentracions més baixes. La manca d’una metodologia més sistemàtica per analitzar el potencial carcinogènic dels DBP ha generat buits a la literatura que s’han de resoldre. A més, els mètodes utilitzats fins ara han dut a resultats que no reflecteixen un escenari real d’exposició. En aquesta tesi proposem l'aplicació d'una metodologia in vitro d'avaluació de riscos carcinogènics basada en l'avaluació d'una àmplia gamma de marcadors de transformació cel·lular, mitjançant la qual s'analitza el potencial carcinogènic i els efectes a llarg termini de dos grups de DBP, HNM i HAA. El principal avantatge d'aquesta metodologia és la possibilitat d'analitzar exposicions prolongades a concentracions més realistes dels DBP, establint així un model d'exposició més realista. Els resultats del nostre primer estudi indiquen que els HNM no són capaços d'induir una transformació tumoral en cèl·lules pulmonars humanes després d'una exposició de 8 setmanes, ni d’induir o augmentar el creixement tumoral. L'avaluació de fibroblasts en contacte amb el CM de cèl·lules exposades, emulant l'estroma tumoral, mostra que en el període d'exposició les cèl·lules estromals no adquireixen la capacitat d'induir el creixement tumoral. L'avaluació de la secreció de MMP determina que ni les cèl·lules exposades ni les cèl·lules estromals podrien secretar aquestes proteïnases que facilitarien la migració tumoral i la metàstasi. El nostre segon estudi mostra que encara que els tres mono-HAA són capaços d'induir dany oxidatiu després d'exposicions agudes, les concentracions no citotòxiques no serien genotòxiques després de 8 setmanes d'exposició. Per contra, les cèl·lules exposades a llarg termini a concentracions no citotòxiques dels HAA desenvolupen resistència als agents oxidants de l'ADN. D’altra banda, l'avaluació in vitro a llarg termini de la carcinogenicitat dels HAA demostra que no poden iniciar una transformació tumorigènica en cèl·lules urotelials. En conjunt, podem concloure que l'ús d'assajos de transformació cel·lular, basat en exposicions prolongades a baixes concentracions, emulant un escenari d'exposició més realista, és una manera més consistent d'avaluar la carcinogenicitat dels DBP. A més, les anàlisis realitzades en aquesta Tesi suggereixen que l'augment de la incidència de càncer vinculat a l'exposició als DBP no pot atribuir-se als HNM ni als HAA.
Disinfection by-products are all those chemical species that are formed during the disinfection of water. To date, more than 600 species of DBPs have been identified in chemically-disinfected waters all over the world. Although epidemiological studies show a clear link between cancer, especially bladder cancer, and DBPs exposure, none of the individual species alone has shown sufficient carcinogenic potency to account for the increased cancer risk. To date, several different models and protocols have been used, attempting to establish the specific genotoxic and carcinogenic properties of individual DBP species. Still, most in vitro hazard evaluations have focused on acute exposures to relatively high concentrations of these chemicals, followed by an extrapolation to low concentrations. The lack of a more systematic methodology to assess the carcinogenic potential of DBPs, generated gaps in the literature that must be resolved. Additionally, current assessment methods led to results that do not reflect real exposure scenarios. In this Thesis we propose the application of an in vitro carcinogenic risk assessment methodology based on the evaluation of a wide range of cell transformation markers, whereby we analyse the carcinogenic potential and long-term effects of two DBPs groups, HNMs and HAAs. The principal advantage of such methodology is the possibility to analyse prolonged exposures to more realistic concentrations of DBPs, thus, setting a more realistic exposure model. Results from our first study indicate that HNMs are not capable of inducing a tumoural transformation in human pulmonary cells after an 8 weeks’ exposure, neither to prompt exposed cells to induce or enhance tumoural growth. The evaluation of fibroblasts grown in contact with the CM of exposed cells, emulating the tumoural stroma, showed that in the exposure period stromal cells did not acquire the capacity to induce tumoural growth. Evaluation of MMPs secretion determined that neither exposed cells nor stromal cells could secrete these proteinases that would facilitate tumoural migration and metastasis. Our second study showed that although all three mono-HAAs appeared capable of inducing oxidative DNA damage after acute exposures, non-cytotoxic concentrations do not appear to be genotoxic after 8 weeks of exposure. On the contrary, cells long-term exposed to non-cytotoxic concentrations of the HAAs developed resistance to DNA-oxidising agents. In vitro long-term carcinogenicity assessment of HAAs proved them unable to initiate a tumorigenic transformation in urothelial cells neither in cells emulating the tumoural stroma. In addition, in any case cells were capable of inducing nor enhancing tumoural growth. Altogether, we conclude that the use of cell transformation assays, based on prolonged exposures to low concentrations, emulating a more realistic exposure scenario, is a more consistent manner to assess the carcinogenicity of DBPs. Additionally, analyses performed in this Thesis suggest that the increased cancer incidence linked to DBPs exposure cannot be attributed to HNMs nor HAAs.

APA, Harvard, Vancouver, ISO, and other styles

29

Tysén, Hannes, and Bore Sköld. "Optimizing profits for hydropower producers using dynamic models : A theoretical approach to solve the optimal use of water over time." Thesis, Umeå universitet, Nationalekonomi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-91778.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Hublart, Paul. "Exploring the use of conceptual catchment models in assessing irrigation water availability for grape growing in the semi-arid Andes." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS181.

Full text

Abstract:

La thèse explore l’utilisation de modèles hydrologiques globaux pour estimer la disponibilité en eau agricole dans le contexte des Andes chiliennes semi-arides. Dans cette région, l’approvisionnement en eau des cultures irriguées de fonds de vallée durant l’été dépend de précipitations se produisant sous forme de neige à haute altitude lors de quelques évènements hivernaux. L’influence des phénomènes ENSO et PDO induit par ailleurs une forte variabilité climatique à l’échelle inter-annuelle, marquée par l’occurrence d’années extrêmement sèches ou humides. La région connaît aussi depuis les années 1980 une progression importante de la viticulture irriguée. Afin de prendre en compte les variations saisonnières et inter-annuelles de la disponibilité et de la consommation en eau d’irrigation, une chaîne de modélisation intégrée a été développée et différentes méthodes de quantification/réduction des incertitudes de simulation ont été mises en œuvre. Les écoulements naturels ont été simulés avec un modèle hydrologique global de type empirique/conceptuel prenant en compte les processus d’accumulation et d’ablation de la neige. En parallèle, les besoins en eau d’irrigation ont été estimés à l’échelle du bassin à partir de modèles phénologiques orientés processus et d’une approche simple du bilan hydrique du sol. Dans l’ensemble, une approche holistique et parcimonieuse a été privilégiée afin de maintenir un niveau d’abstraction mathématique et de représentation des processus équivalent à celui des modèles de bassin couramment utilisés. Afin d’améliorer l’utilité et la fiabilité des simulations obtenues en contexte de changement ou de forte variabilité climatique, l’effet des températures extrêmes sur le développement des cultures et l’impact des pertes en eau par sublimation à haute altitude ont fait l’objet d’une attention particulière. Ce cadre de modélisation conceptuel a été testé pour un bassin typique des Andes semi-arides (1512 km2, 820–5500 m a.s.l.) sur une période de 20 ans incluant une large gamme de conditions climatiques et des pratiques agricoles non-stationnaires (évolution des variétés de vigne, des surfaces et modes d’irrigation, etc). L’évaluation des modèles a été réalisée dans un cadre bayésien en faisant l’hypothèse d’erreurs auto-corrélées, hétéroscédastiques et non-gaussiennes. Différents critères et sources de données ont par ailleurs été mobilisés afin de vérifier l’efficacité et la cohérence interne de la chaîne de modélisation ainsi que la fiabilité statistique et la finesse des intervalles de confiance obtenus. De manière alternative, une caractérisation des erreurs de structure et de l’ambiguïté propre au choix du modèle hydrologique a été réalisée de manière non-probabiliste à partir d’une plate-forme de modélisation modulaire. Dans l’ensemble, la prise en compte explicite de la consommation en eau des cultures a mis en valeur certaines interactions entre paramètres hydrologiques et permis d’améliorer la fiabilité des simulations hydrologiques en année sèche. Finalement, une étude de sensibilité à différents seuils d’augmentation de la température et de la concentration en CO2 a été effectuée afin d’évaluer l’impact potentiel des changements climatiques sur le comportement de l’hydrosystème et la capacité à satisfaire la demande en eau d’irrigation dans le futur
This thesis investigates the use of lumped catchment models to assess water availability for irrigation in the upland areas of northern-central Chile (30°S). Here, most of the annual water supply falls as snow in the high Cordillera during a few winter storms. Seasonal snowpacks serve as natural reservoirs, accumulating water during the winter and sustaining streams and aquifers during the summer, when irrigation demand in the cultivated valleys is at its peak. At the inter-annual timescale, the influence of ENSO and PDO phenomena result in the occurrence of extremely wet and dry years. Also, irrigated areas and grape growing have achieved a dramatic increase since the early 1980s. To evaluate the usefulness of explicitly accounting for changes in irrigation water-use in lumped catchment models, an integrated modeling framework was developed and different ways of quantifying/reducing model uncertainty were explored. Natural streamflow was simulated using an empirical hydrological model and a snowmelt routine. In parallel, seasonal and inter-annual variations in irrigation requirements were estimated using several process-based phenological models and a simple soil-water balance approach. Overall, this resulted in a low-dimensional, holistic approach based on the same level of mathematical abstraction and process representation as in most commonly-used catchment models. To improve model reliability and usefulness under varying or changing climate conditions, particular attention was paid to the effects of extreme temperatures on crop phenology and the contribution of sublimation losses to water balance at high elevations. This conceptual framework was tested in a typical semi-arid Andean catchment (1512 km2, 820–5500 m a.s.l.) over a 20–year simulation period encompassing a wide range of climate and water-use conditions (changes in grape varieties, irrigated areas, irrigation techniques). Model evaluation was performed from a Bayesian perspective assuming auto-correlated, heteroscedastic and non-gaussian residuals. Different criteria and data sources were used to verify model assumptions in terms of efficiency, internal consistency, statistical reliability and sharpness of the predictive uncertainty bands. Alternatively, a multiple-hypothesis and multi-criteria modeling framework was also developed to quantify the importance of model non-uniqueness and structural inadequacy from a non-probabilistic perspective. On the whole, incorporating the effects of irrigation water-use led to new interactions between the hydrological parameters of the modeling framework and improved reliability of streamflow predictions during low-flow periods. Finally, a sensitivity analysis to changes in climate conditions was conducted to evaluate the potential impacts of increasing temperatures and atmospheric CO2 on the hydrological behavior of the catchment and the capacity to meet future water demands

APA, Harvard, Vancouver, ISO, and other styles

31

Noronha, Sannervik Angela. "Modelling productivity of willow stands in Sweden : evaluation of concepts for radiation use efficiency and soil water and nitrogen availability /." Uppsala : Dept. of Short Rotation Forestry, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/s286-ab.html.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Minunno, Francesco. "On the use of the bayesian approach for the calibration, evaluation and comparison of process-based forest models." Doctoral thesis, ISA/UL, 2014. http://hdl.handle.net/10400.5/7350.

Full text

Abstract:

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
Forest ecosystems have been experiencing fast and abrupt changes in the environmental conditions, that can increase their vulnerability to extreme events such as drought, heat waves, storms, fire. Process-based models can draw inferences about future environmental dynamics, but the reliability and robustness of vegetation models are conditional on their structure and their parametrisation. The main objective of the PhD was to implement and apply modern computational techniques, mainly based on Bayesian statistics, in the context of forest modelling. A variety of case studies was presented, spanning from growth predictions models to soil respiration models and process-based models. The great potential of the Bayesian method for reducing uncertainty in parameters and outputs and model evaluation was shown. Furthermore, a new methodology based on a combination of a Bayesian framework and a global sensitivity analysis was developed, with the aim of identifying strengths and weaknesses of process-based models and to test modifications in model structure. Finally, part of the PhD research focused on reducing the computational load to take full advantage of Bayesian statistics. It was shown how parameter screening impacts model performances and a new methodology for parameter screening, based on canonical correlation analysis, was presented

APA, Harvard, Vancouver, ISO, and other styles

33

Keller, Kathrin M., Sebastian Lienert, Anil Bozbiyik, Thomas F. Stocker, (Sidorova) Olga V. Churakova, David C. Frank, Stefan Klesse, et al. "20th century changes in carbon isotopes and water-use efficiency: tree-ring-based evaluation of the CLM4.5 and LPX-Bern models." COPERNICUS GESELLSCHAFT MBH, 2017. http://hdl.handle.net/10150/624331.

Full text

Abstract:

Measurements of the stable carbon isotope ratio (delta C-13) on annual tree rings offer new opportunities to evaluate mechanisms of variations in photosynthesis and stomatal conductance under changing CO2 and climate conditions, especially in conjunction with process-based biogeochemical model simulations. The isotopic discrimination is indicative of the ratio between the CO2 partial pressure in the intercellular cavities and the atmosphere (c(i)/c(a)) and of the ratio of assimilation to stomatal conductance, termed intrinsic water-use efficiency (iWUE). We performed isotope-enabled simulations over the industrial period with the land biosphere module (CLM4.5) of the Community Earth System Model and the Land Surface Processes and Exchanges (LPX-Bern) dynamic global vegetation model. Results for C3 tree species show good agreement with a global compilation of delta C-13 measurements on leaves, though modeled C-13 discrimination by C3 trees is smaller in arid regions than measured. A compilation of 76 tree-ring records, mainly from Europe, boreal Asia, and western North America, suggests on average small 20th century changes in isotopic discrimination and in c(i)/c(a) and an increase in iWUE of about 27% since 1900. LPX-Bern results match these century-scale reconstructions, supporting the idea that the physiology of stomata has evolved to optimize trade-offs between carbon gain by assimilation and water loss by transpiration. In contrast, CLM4.5 simulates an increase in discrimination and in turn a change in iWUE that is almost twice as large as that revealed by the tree-ring data. Factorial simulations show that these changes are mainly in response to rising atmospheric CO2. The results suggest that the downregulation of c(i)/c(a) and of photosynthesis by nitrogen limitation is possibly too strong in the standard setup of CLM4.5 or that there may be problems associated with the implementation of conductance, assimilation, and related adjustment processes on long-term environmental changes.

APA, Harvard, Vancouver, ISO, and other styles

34

O'Hara, Jeffrey Keith. "Water resources planning under climate change and variability." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3259069.

Full text

Abstract:

Thesis (Ph. D.)--University of California, San Diego, 2007.
Title from first page of PDF file (viewed June 21, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.

APA, Harvard, Vancouver, ISO, and other styles

35

Sahu, Parameswar. "Use of Time Series, Barometric and Tidal Analyses to Conceptualize and Model Flow in an Underground Mine: The Corning Mine Complex, Ohio." Ohio University / OhioLINK, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1108395116.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Casari, Matheus Puttinati 1989. "Uso da espectroscopia por impedância para a medição da fração volumétrica de água em emulsões de água e óleo : The use of impedance spectroscopy for the water concentration measurement in water and oil emulsions." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265959.

Full text

Abstract:

Orientador: Niederauer Mastelari
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-24T20:16:15Z (GMT). No. of bitstreams: 1 Casari_MatheusPuttinati_M.pdf: 7346334 bytes, checksum: 21f16ea44e6fdefa2b0445fe1a0b6b3a (MD5) Previous issue date: 2014
Resumo: A concentração volumétrica de água na produção de óleo cru é um parâmetro constantemente monitorado para acompanhar as sempre inconstantes propriedades do reservatório assim com para razões de otimização; resumindo, o que é importante é o volume de óleo na produção. A medição da concentração volumétrica de água é geralmente feita em bancada (colhendo uma amostra da produção e analisando-a em um laboratório) ou por sensores que monitoram a concentração em tempo real. Uma das técnicas utilizadas para a medição online da concentração de água é a espectroscopia por impedância. De fato, propriedades dielétricas e condutivas formam a impedância elétrica da solução. Na presente análise foram considerados os dois tipos básicos de emulsão: água em óleo (A/O) e óleo em água (O/A). O objetivo deste trabalho foi comparar a concentração de água medida com a predição do modelo matemático baseado nas medições das propriedades dielétricas e condutivas da solução. As emulsões de água e óleo foram sintetizadas em condições de laboratório. A concentração de água variou entre 13,1% à 41,1% em volume para as emulsões A/O e de 50% à 60% em volume para as emulsões O/A à temperaturas de 25°C à 62°C e salinidade da água de 0 (água deionizada), 1Kg/m³ e 10Kg/m³ de NaCl. A constante dielétrica e condutividade das emulsões foram medidas em um sensor composto por dois cilindros concêntricos cuja área dos eletrodos é bem maior que a distância entre eles. Essa geometria favorece os efeitos polarização e é apropriada para materiais dielétricos como as emulsões A/O, além de aumentar o erro de medição em soluções condutivas. Para melhores resultados com as emulsões O/A foi utilizado em sensor de placas paralelas com uma distância entre eletrodos bem maior que a sua área o que favorece os efeitos de transporte de carga. Os dados foram medidos por uma Ponte RLC de precisão Agilent E4980A em uma faixa de frequência de 20Hz à 1MHz. Os dados obtidos nos testes foram proporcionais à concentração de água na solução e seguiram o modelo matemático de Maxwell com um erro máximo de 4%. Os resultados também mostraram que a constante dielétrica não sofre influência significativa da temperatura e salinidade da água, assim como a medida do volume de água. Já para as emulsões O/A os testes mostraram grande influência da temperatura e salinidade da água nas medições, onde o conhecimento prévio destas condições é imprescindível ao método
Abstract: The volumetric concentration of water in crude oil production is a parameter constantly monitored to access the ever changing reservoir properties as well as for economical purposes; after all what is needed is the net oil production. The measurement of water concentration is usually done in over-the-bench (sampling the crude stream and screening in a chemistry lab) or by online instruments which continuously monitor the concentration. One of the techniques for online assessment of water concentration is the impedance spectroscopy. In fact, the dielectric and conductive property of the liquid phase is proportional to the electrical impedance. In the present analysis it was considered the two basic types of emulsions: the water in oil (W/O) and the oil in water (O/W). The objective of this work was to compare the measured water concentration against model's prediction based on the measured dielectric and conductive properties of the emulsions. The water and oil emulsions were synthesized in laboratory conditions. The water concentration range was 13.1% to 41.1% (v/v) for W/O emulsions and 50% to 60% (v/v) for O/W emulsions at temperatures of 25oC to 62oC and water salinity of 0 (de-ionized water), 1Kg/m³ and 10Kg/m³ of NaCl. The emulsion dielectric constant and conductivity were measured in a sensor made by two concentric cylinders whose electrodes area is much bigger than the distance between them. This geometry favors the polarization effects and is appropriate for dielectric solution as A/O emulsions. For better results for the O/A emulsion it was used a parallel electrode sensor where the distance between the electrodes is much bigger than the electrodes area which favors the charge transport effects. The data were measured by the Precision LCR Meter Agilent E4980A in a frequency range of 20Hz to 1MHz. The experimental data was found proportional to the volumetric concentration and follows Maxwell correlation within 4%. The experimental tests also disclosed that the dielectric constant, or the volumetric concentration, were almost insensitive to the changes in temperature and in salinity and so the water concentration of W/O emulsions. For O/W emulsions the tests showed a great influence of the temperature and salinity on the conductivity measurements. So, for O/W emulsions the temperature and water salinity must be considered
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica

APA, Harvard, Vancouver, ISO, and other styles

37

Zhang, Shulan. "Soil hydraulic properties and water balance under various soil management regimes on the Loess Plateau, China /." Umeå : Dept. of Forest Ecology, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/2005126.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Snygg, Oliver, and Carl Torberger. "Vilka nya markanadsmodeller kanfå producerande företag att gå motcirkulär ekonomi?" Thesis, KTH, Industriell produktion, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-255347.

Full text

Abstract:

Miljömedvetenheten i världen ökar. Samhällsdebatten formas allt mer av ett miljöperspektiv på flera olika fronter. Allt fler börjar förstå att jordens resurser är ändliga och vi måste tänka om hur vi lever idag. Den producerande industrin står för stor dela avbrukandet av råmaterial, men hur kommer industrin se ut i framtiden?Framtidens industri beskrivs ofta som en cirkulär ekonomi där minimala mängder råmaterial bryts och den största parten av det material som faller ur användning går återin i produktionen. Verkligheten vi lever i idag är en annan, större parten av världensindustri fortsätter med linjär produktion där råmaterial brukas i tillverkningen och produkter deponeras vid slutet av dess livscykel. Projektgruppen undersöker byggstenarna inom cirkulär ekonomi och var vi egentligen befinner oss i utveckling mot en hållbarare hantering av råvaror. Syftet med rapporten är att utreda vilka ekonomiska drivkrafter som finns för företag att själva gå mot cirkulär ekonomi i form av nya marknadsmodeller. Möjligheter till dessa marknadsmodeller växer ofta fram med hjälp av ny teknik från Industri 4.0 som Internet of Things och Big Data. Vi har nått slutsatsen att marknadsmodeller som pay-per-use där företagen behåller ägandet av produkten ofta är enkla att implementera i cirkulär ekonomi, då företaget själva kan kontrollera hela kretsloppet för produkten. De underlättar om man ska basera sin produktion på retur av produkter om man själv har kontroll över volymerna. Dessa modeller bygger ofta på att man säljer service-baserade tjänster som är beroende av Internet of Things och Big Data.
Environmental awareness in the world is increasing. The social debate is increasingly formed by an environmental perspective on several fronts. More and more people are beginning to understand that the earth's resources are finite and we must think about how we live today. The producing industry accounts for a large part of the use of raw materials, but how will the industry change in the future? The industry of the future is often described as a circular economy where minimal amounts of raw materials are broken and the majority of the material that is in use goes back to production. The reality we live in today is another, the greater part of the world's industry continues with linear production where raw materials are used in manufacturing and products are deposited at the end of its lifecycle. The project group examines the building blocks of circular economy and where we are today in the development towards sustainable management of raw materials. The purpose of the report is to investigate the economic advantages for companies to change to circular economy in the form of new business models. Opportunities for these business models often grow with the help of new technology from Industry 4.0 like Internet ofThings and Big Data. We have the conclusion that business models such as pay-per-use where companies maintain ownership of the product, often are easy to implement in circular economics, since the company itself can control the entire circuit for the product. They make it easier to base their production on return of products if they control the volumes of the returned products themself. These models are often based on selling services that are dependent on the Internet of things and Big Data.

APA, Harvard, Vancouver, ISO, and other styles

39

Snygg, Oliver, and Carl Torberger. "Vilka nya marknadsmodeller kan få producerande företag att gå mot cirkulär ekonomi?" Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264557.

Full text

Abstract:

Miljömedvetenheten i världen ökar. Samhällsdebatten formas allt mer av ett miljöperspektiv på flera olika fronter. Allt fler börjar förstå att jordens resurser är ändliga och vi måste tänka om hur vi lever idag. Den producerande industrin står för stor dela av brukandet av råmaterial, men hur kommer industrin se ut i framtiden? Framtidens industri beskrivs ofta som en cirkulär ekonomi där minimala mängder råmaterial bryts och den största parten av det material som faller ur användning går åter in i produktionen. Verkligheten vi lever i idag är en annan, större parten av världens industri fortsätter med linjär produktion där råmaterial brukas i tillverkningen och produkter deponeras vid slutet av dess livscykel. Projektgruppen undersöker byggstenarna inom cirkulär ekonomi och var vi egentligen befinner oss i utveckling mot en hållbarare hantering av råvaror. Syftet med rapporten är att utreda vilka ekonomiska drivkrafter som finns för företag att själva gå mot cirkulär ekonomi i form av nya marknadsmodeller. Möjligheter till dessa marknadsmodeller växer ofta fram med hjälp av ny teknik från Industri 4.0 som Internet of Things och Big Data. Vi har nått slutsatsen att marknadsmodeller som pay-per-use där företagen behåller ägandet av produkten ofta är enkla att implementera i cirkulär ekonomi, då företaget själva kan kontrollera hela kretsloppet för produkten. De underlättar om man ska basera sin produktion på retur av produkter om man själv har kontroll över volymerna. Dessa modeller bygger ofta på att man säljer service-baserade tjänster som är beroende av Internet of Things och Big Data.
Environmental awareness in the world is increasing. The social debate is increasingly formed by an environmental perspective on several fronts. More and more people are beginning to understand that the earth's resources are finite and we must think about how we live today. The producing industry accounts for a large part of the use of raw materials, but how will the industry change in the future? The industry of the future is often described as a circular economy where minimal amounts of raw materials are broken and the majority of the material that is in use goes back to production. The reality we live in today is another, the greater part of the world's industry continues with linear production where raw materials are used in manufacturing and products are deposited at the end of its lifecycle. The project group examines the building blocks of circular economy and where we are today in the development towards sustainable management of raw materials. The purpose of the report is to investigate the economic advantages for companies to change to circular economy in the form of new business models. Opportunities for these business models often grow with the help of new technology from Industry 4.0 like Internet of Things and Big Data. We have the conclusion that business models such as pay-per-use where companies maintain ownership of the product, often are easy to implement in circular economics, since the company itself can control the entire circuit for the product. They make it easier to base their production on return of products if they control the volumes of the returned products themself. These models are often based on selling services that are dependent on the Internet of things and Big Data.

APA, Harvard, Vancouver, ISO, and other styles

40

Wetzell, Lauren McKinnon. "Simple Models For Predicting Dune Erosion Hazards Along The Outer Banks Of North Carolina." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000191.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Clingenpeel, Glenn C. (Glenn Christopher). "Conception and Design of Constructed Wetland Systems to Treat Wastewater at the Biosphere 2 Center with Use of Reaction Rate Models and the Habitat Evaluation Procedure to Determine the Effects of Designing for Wildlife Habitat on Treatment Efficiency." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc278445/.

Full text

Abstract:

A study was undertaken to explore relationships between wetland characteristics which make them efficient water purifiers versus their ability to serve as wildlife habitat. The effects of designing constructed wetlands for improved habitat on water treatment efficiencies were quantified. Results indicate that some sacrifice in treatment efficiency is required and that the degree of efficiency reduction is dependant upon pollutant loading rates. However, sacrifice in efficiency is much smaller than increase in habitat quality, and can be offset by increasing wetland area. A practical, theoretical application was then attempted.

APA, Harvard, Vancouver, ISO, and other styles

42

Stipinovich, Amalia. "Change in land cover and water abstraction : modelling runoff effects in the Bot River Catchment." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1654.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Vilanculos, Agostinho Chuquelane Fadulo. "The use of hydrological information to improve flood management-integrated hydrological modelling of the Zambezi River basin." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1018915.

Full text

Abstract:

The recent high profile flooding events – that have occurred in many parts of the world – have drawn attention to the need for new and improved methods for water resources assessment, water management and the modelling of large-scale flooding events. In the case of the Zambezi Basin, a review of the 2000 and 2001 floods identified the need for tools to enable hydrologists to assess and predict daily stream flow and identify the areas that are likely to be affected by flooding. As a way to address the problem, a methodology was set up to derive catchment soil moisture statistics from Earth Observation (EO) data and to study the improvements brought about by an assimilation of this information into hydrological models for improving reservoir management in a data scarce environment. Rainfall data were obtained from the FEWSNet Web site and computed by the National Oceanic and Atmospheric Administration Climatic Prediction Center (NOAA/CPC). These datasets were processed and used to monitor rainfall variability and subsequently fed into a hydrological model to predict the daily flows for the Zambezi River Basin. The hydrological model used was the Geospatial Stream Flow Model (GeoSFM), developed by the United States Geological Survey (USGS). GeoSFM is a spatially semi-distributed physically-based hydrological model, parameterised using spatially distributed topographic data, soil characteristics and land cover data sets available globally from both Remote Sensing and in situ sources. The Satellite rainfall data were validated against data from twenty (20) rainfall gauges located on the Lower Zambezi. However, at several rain gauge stations (especially those with complex topography, which tended to experience high rainfall spatial variability), there was no direct correlation between the satellite estimates and the ground data as recorded in daily time steps. The model was calibrated for seven gauging stations. The calibrated model performed quite well at seven selected locations (R2=0.66 to 0.90, CE=0.51 to 0.88, RSR=0.35 to 0.69, PBIAS=−4.5 to 7.5). The observed data were obtained from the National Water Agencies of the riparian countries. After GeoSFM calibration, the model generated an integration of the flows into a reservoir and hydropower model to optimise the operation of Kariba and Cahora Bassa dams. The Kariba and Cahora Bassa dams were selected because this study considers these two dams as the major infrastructures for controlling and alleviating floods in the Zambezi River Basin. Other dams (such as the Kafue and Itezhi-Thezi) were recognised in terms of their importance but including them was beyond the scope of this study because of financial and time constraints. The licence of the reservoir model was limited to one year for the same reason. The reservoir model used was the MIKE BASIN, a professional engineering software package and quasi-steady-state mass balance modelling tool for integrated river basin and management, developed by the Denmark Hydraulic Institute (DHI) in 2003. The model was parameterised by the geometry of the reservoir basin (level, area, volume relationships) and by the discharge-level (Q-h) relationship of the dam spillways. The integrated modelling system simulated the daily flow variation for all Zambezi River sub-basins between 1998 and 2008 and validated between 2009 and 2011. The resulting streamflows have been expressed in terms of hydrograph comparisons between simulated and observed flow values at the four gauging stations located downstream of Cahora Bassa dam. The integrated model performed well, between observed and forecast streamflows, at four selected gauging stations (R2=0.53 to 0.90, CE=0.50 to 0.80, RSR=0.49 to 0.69, PBIAS=−2.10 to 4.8). From the results of integrated modelling, it was observed that both Kariba and Cahora Bassa are currently being operated based on the maximum rule curve and both remain focused on maximising hydropower production and ensuring dam safety rather than other potential influences by the Zambezi River (such as flood control downstream – where the communities are located – and environmental issues). In addition, the flood mapping analysis demonstrated that the Cahora Bassa dam plays an important part in flood mitigation downstream of the dams. In the absence of optimisation of flow releases from both the Kariba and Cahora Bassa dams, in additional to the contribution of any other tributaries located downstream of the dams, the impact of flooding can be severe. As such, this study has developed new approaches for flood monitoring downstream of the Zambezi Basin, through the application of an integrated modelling system. The modelling system consists of: predicting daily streamflow (using the calibrated GeoSFM), then feeding the predicted streamflow into MIKE BASIN (for checking the operating rules) and to optimise the releases. Therefore, before releases are made, the flood maps can be used as a decision-making tool to both assess the impact of each level of release downstream and to identify the communities likely to be affected by the flood – this ensures that the necessary warnings can be issued before flooding occurs. Finally an integrated flood management tool was proposed – to host the results produced by the integrated system – which would then be accessible for assessment by the different users. These results were expressed in terms of water level (m). Four discharge-level (Q-h) relationships were developed for converting the simulated flow into water level at four selected sites downstream of Cahora Bassa dam – namely: Cahora Bassa dam site, Tete (E-320), Caia (E-291) and Marromeu (E-285). However, the uncertainties in these predictions suggested that improved monitoring systems may be achieved if data access at appropriate scale and quality was improved.

APA, Harvard, Vancouver, ISO, and other styles

44

Tita-Goldstein, Amal. "Mise en forme des poudres par compression : influence du procédé et de la formulation pour la maitrise des propriétés d'usage." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0238/document.

Full text

Abstract:

Ce travail porte sur l'étude de liens entre les propriétés mécaniques de comprimés modèles composés de billes de verre et les caractéristiques physico-chimiques des liants, constitués de sucres et préparés sous forme de sirops. Le procédé de fabrication consiste en une méthode modifiée de compression humide. Deux paramètres de formulation ont été testés : le taux de saturation en sirop et sa concentration massique. Nous en avons tiré une variable unique qui est la fraction massique de sucre ajoutée aux billes de verre. Ces paramètres se sont avérés essentiels dans la maîtrise de la tenue mécanique des comprimés. Il en est de même pour leurs conditions de stockage. Une corrélation linéaire a été établie entre une activité de l'eau, définie comme critique, du fructose, du galactose, du glucose, du lactose et du saccharose et l'apparition du phénomène de transition vitreuse pour chacun de ces sucres, engendrant une chute brutale dans la résistance mécanique de leurs comprimés respectifs. Le taux de cristallisation des sucres et l'absence d'anomérie sont aussi des paramètres qui semblent être à l'origine d'une meilleure tenue mécanique des comprimés
This work focuses on the study of relationships between the mechanical properties of model compacts composed by glass beads and the physicochemical characteristics of binders consisting of sugars and prepared in the form of syrups. Fructose, galactose, glucose, lactose and sucrose were used in this study. The manufacturing process consists in a modified wet compression method. Two formulation parameters were tested: the saturation ratio and the mass concentration of the syrup. We deduced from them a single variable which is the mass fraction of sugar added to the glass beads. These parameters were essential in controlling the mechanical strength of the compacts. It has been shown that storage conditions also influence tablets properties. A linear correlation was established between a specific water activity value, defined as critical, and the glass transition temperature for each of sugars, resulting in a collapse in mechanical strength of the compacts. The rate of crystallization of sugar and the absence of anomeric forms are also parameters that seem to be targeted in order to increase compacts mechanical strength

APA, Harvard, Vancouver, ISO, and other styles

45

Tazzo, Ivonete Fátima. "Modelagem da evapotranspiração máxima para as culturas do pimentão e do tomateiro em estufa plástica na primavera." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/3171.

Full text

Abstract:

Conselho Nacional de Desenvolvimento Científico e Tecnológico
Growing crops in protected environment aiming to increase productivity and quality of vegetables is commonly used in Southern Brazil , mainly to reduce the seasonality of production caused by a winter cold season. Sweet pepper is an alternative profitable crop to rotate with other crops inside greenhouse, because of their adaptation and tomato is the most cultivated crop in these environments in Brazil . The cultivation during the Spring inside plastic greenhouses is used to take advantage of a previous area and structure already assembled, as most growers are small farmers. Moreover, an important advantage is the quality and earliness of crops grown in these environments. In order to achieve these goals and reach the potential yield, water demand has to be met through irrigation. An inadequate irrigation, both surplus and shortage, may not only decrease yield, but also may lead to diseases and leaching of ions, mainly nitrates. Aiming to develop, test and evaluate regression models to calculate maximum evapotranspiration based upon meteorological and crop variables for sweet pepper (Capsicum annuum L) and tomato (Lycopersicon esculentum, Mill) grown in plastic greenhouse during the Spring, an experiment was conducted during the Spring of the 2005 and during of the 2006, in a plastic greenhouse in the Crop Production Department of the Federal University of Santa Maria. Maximum evapotranspiration (ETm) of sweet pepper and tomato was determined with three drainage lysimeters filled with substrate for each crop. The ETm (in mm) was obtained from the difference between irrigated and drained water. Regression models to estimate the ETm were generated using the experimental data measured during the Spring of 2005, being selected only those with the slope parameters significant by the t test (p <0.05) and with coefficient of determination (R2) greater than 0.60. The performance of the selected models was evaluated using the experimental data collected during the Spring 2006. Statistics used for models evaluation were: mean square root error (RMSE), coefficient of determination (R2), coefficient of correlation (r), coefficient of accuracy or agreement (d) and coefficient of confidence (c) and models were ranked based upon the coefficient of confidence and the "sum of the values of the ordinary positions" of all the statistics (åPO). Results showed that leaf area index and plant height are the crop variables that result in the best performance of the model to estimate ETm of sweet pepper and tomato grown in greenhouses during the Spring. Models that consider Etm divided by the root square of leaf area index showed good performance, although in their generation they were not always the best ones. Air vapor pressure deficit and incoming solar radiation measured inside greenhouses, and air vapor pressure deficit, incoming solar radiation, net radiation and reference evapotranspiration measured outside the greenhouse, are the meteorological variables that presented the best ETm estimation for sweet pepper and tomato grown in plastic greenhouse during the spring.
O cultivo em ambiente protegido é utilizado na região Sul do Brasil, com o intuito de aumentar a produtividade e a qualidade de olerícolas e principalmente para diminuir a sazonalidade de produção, devido a uma estação fria. O pimentão é uma alternativa de rotação de culturas economicamente viável para o cultivo em estufas, devido à sua adaptação e o tomateiro é a olerícola mais cultivada nesses ambientes no Brasil. O cultivo na primavera no interior de estufas é usado para aproveitar a estrutura já montada e da área, pois a maioria das propriedades é de pequeno porte. Além disso, a grande vantagem é a qualidade e a precocidade das culturas nesses ambientes. Para se atingir esses objetivos é necessária a irrigação para atender a demanda hídrica das culturas e dessa forma atingir o potencial produtivo. A irrigação inadequada, em excesso e ou por escassez, além de comprometer o rendimento da cultura pode causar problemas de doenças e ao ambiente devido à lixiviação de íons, principalmente, de nitratos. Com o objetivo de gerar, testar e avaliar modelos de regressão para determinar a evapotranspiração máxima em função de variáveis meteorológicas e fenométricas das culturas do tomateiro e do pimentão cultivados em estufa plástica na primavera, foi realizado um experimento na primavera de 2005 e um na primavera de 2006, em uma estufa plástica do Departamento de Fitotecnia da Universidade Federal de Santa Maria. A evapotranspiração máxima (ETm) do pimentão (Capsicum annuum L) e do Tomateiro (Lycopersicon esculentum, Mill), foi determinada com 3 lisímetros de drenagem com substrato para cada cultura, sendo a ETm (em mm) obtida pela diferença entre a água irrigada e drenada. Os modelos de regressão para a estimativa da ETm foram gerados utilizando o banco de dados experimentais obtidos na primavera de 2005, sendo selecionados apenas os que apresentaram parâmetros angulares significativos pelo teste t (p < 0,05) e coeficiente de determinação (R2) maior do que 0,60. Os testes dos modelos de estimativa da ETm selecionados foram efetuados com os dados experimentais obtidos na primavera de 2006, para o que se utilizaram os valores das estatísticas: raiz do quadrado médio do erro (RMSE), coeficientes de determinação (R2), de correlação (r), de exatidão ou concordância (d) e de confiança (c). A análise do desempenho dos modelos foi realizada através dos valores do coeficiente de confiança e do somatório dos valores das posições ordinais das estatísticas de avaliação (åPO). Verificou-se que o índice de área foliar e a altura de plantas são as variáveis fenométricas que propiciam melhor desempenho dos modelos de estimativa da ETm do pimentão e do tomateiro cultivados em estufa na primavera. Os modelos que incluem a divisão da ETm do pimentão e do tomateiro pela raiz quadrada do índice de área foliar mostram desempenho classificado como Bom quando testados, embora na sua geração nem sempre sejam os melhores. O déficit de saturação do ar e a radiação solar global incidente no interior da estufa, e o déficit de saturação do ar, a radiação solar global, o saldo de radiação e a evapotranspiração de referência no exterior da estufa, são as variáveis meteorológicas que apresentaram os melhores resultados na estimativa da ETm do pimentão e do tomateiro cultivados na primavera em estufa plástica.

APA, Harvard, Vancouver, ISO, and other styles

46

Goward, Kelly J. "Relationship of nutrients and pesticides to landuse characteristics in three subwatersheds of the upper White River, IN." Virtual Press, 2004. http://liblink.bsu.edu/uhtbin/catkey/1286601.

Full text

Abstract:

Stream samples were tested at 18 sites in three subwatersheds of the Upper White River for ammonia, nitrate, orthophosphate, atrazine, and diazinon. Nutrient results were tested with a general linear model and in linear regressions with selected landuse characteristics. A critical areas index for surface runoff of pollutants was created using a geographic information system. Comparisons were made between results obtained by Ball State University and by the Muncie Bureau of Water Quality and other outside laboratories. Most mean concentrations of nutrients were likely related to combinations of agricultural and residential landuse factors. Only concentrations of ammonia and orthophosphate were significantly related (a = 0.05) to any landuse characteristics. Atrazine levels were high in the spring, but decreased in the fall. Results suggest that improved or increased best management practices should be implemented in these subwatersheds to control non-point source pollution of the streams.
Department of Natural Resources and Environmental Management

APA, Harvard, Vancouver, ISO, and other styles

47

Yen, Jeffrey Lee. "A system model for assessing water consumption across transportation modes in urban mobility networks." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39527.

Full text

Abstract:

Energy and environmental impacts are two factors that will influence urban region composition in the near future. One emerging issue is the effect on water usage resulting from changes in regional or urban transportation trends. With many regions experiencing stresses on water availability, transportation planners and users need to combine information on transportation-related water consumption for any region and assess potential impacts on local water resources from the expansion of alternative transportation modes. This thesis will focus on use-phase water consumption factors for multiple vehicle modes, energy and fuel pathways, roads, and vehicle infrastructure for a given transportation network. While there are studies examining life cycle impacts for energy generation and vehicle usage, few repeatable models exist for assessing overall water consumption across several transportation modes within urban regions. As such, the question is: is it possible to develop a traceable decision support model that combines and assesses water consumption from transportation modes and related mobility infrastructure for a given mobility network? Based on this, an object-oriented system model of transportation elements was developed using the Systems Modeling Language (SysML) and Model-Based Systems Engineering principles to compare water consumption across vehicle modes for assessing the resiliency of existing infrastructure and water resources. To demonstrate the intent of this model, daily network usage water consumption will be analyzed for current and alternative network scenarios projected by policies regarding the expansion of alternative energy. The model is expected to show variations in water consumption due to fluctuations in energy pathways, market shares, and driving conditions, from which the model should help determine the feasibility of expanding alterative vehicles and fuels in these networks. While spatially explicit data is limited compared to the national averages that are used as model inputs, the analytical framework within this model closely follows that of existing assessments and the reusable nature of SysML model elements allows for the future expansion of additional transportation modes and infrastructure as well as other environmental analyses.

APA, Harvard, Vancouver, ISO, and other styles

48

Sandels, Claes. "Modeling and Simulation of Electricity Consumption Profiles in the Northern European Building Stock." Doctoral thesis, KTH, Elkraftteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184093.

Full text

Abstract:

The electric power systems are currently being transformed through the integration of intermittent renewable energy resources and new types of electric loads. These developments run the risk of increasing mismatches between electricity supply and demand, and may cause non-favorable utilization rates of some power system components. Using Demand Response (DR) from flexible loads in the building stock is a promising solution to overcome these challenges for electricity market actors. However, as DR is not used at a large scale today, there are validity concerns regarding its cost-benefit and reliability when compared to traditional investment options in the power sector, e.g. network refurbishment. To analyze the potential in DR solutions, bottom-up simulation models which capture consumption processes in buildings is an alternative. These models must be simple enough to allow aggregations of buildings to be instantiated and at the same time intricate enough to include variations in individual behaviors of end-users. This is done so the electricity market actor can analyze how large volumes of flexibility acts in various market and power system operation contexts, but also can appreciate how individual end-users are affected by DR actions in terms of cost and comfort. The contribution of this thesis is bottom-up simulation models for generating load profiles in detached houses and office buildings. The models connect end-user behavior with the usage of appliances and hot water loads through non-homogenous Markov chains, along with physical modeling of the indoor environment and consumption of heating and cooling loads through lumped capacitance models. The modeling is based on a simplified approach where openly available data and statistics are used, i.e. data that is subject to privacy limitations, such as smart meter measurements are excluded. The models have been validated using real load data from detached houses and office buildings, related models in literature, along with energy-use statistics from national databases. The validation shows that the modeling approach is sound and can provide reasonably accurate load profiles as the error results are in alignment with related models from other research groups. This thesis is a composite thesis of five papers. Paper 1 presents a bottom-up simulation model to generate load profiles from space heating, hot water and appliances in detached houses. Paper 2 presents a data analytic framework for analyzing electricity-use from heating ventilation and air conditioning (HVAC) loads and appliance loads in an office building. Paper 3 presents a non-homogeneous Markov chain model to simulate representative occupancy profiles in single office rooms. Paper 4 utilizes the results in paper 2 and 3 to describe a bottom-up simulation model that generates load profiles in office buildings including HVAC loads and appliances. Paper 5 uses the model in paper 1 to analyze the technical feasibility of using DR to solve congestion problems in a distribution grid.
Integrering av förnybara energikällor och nya typer av laster i de elektriska energisystemen är möjliga svar till klimatförändringar och uttömning av ändliga naturresurser. Denna integration kan dock öka obalanserna mellan utbud och efterfrågan av elektricitet, och orsaka en ogynnsam utnyttjandegrad av vissa kraftsystemkomponenter. Att använda efterfrågeflexibilitet (Demand Response) i byggnadsbeståndet är en möjlig lösning till dessa problem för olika elmarknadsaktörer. Men eftersom efterfrågeflexibilitet inte används i stor skala idag finns det obesvarade frågor gällande lösningens kostnadsnytta och tillförlitlighet jämfört med traditionella investeringsalternativ i kraftsektorn. För att analysera efterfrågeflexibilitetslösningar är botten-upp-simuleringsmodeller som fångar elförbrukningsprocesser i byggnaderna ett alternativ. Dessa modeller måste vara enkla nog för att kunna representera aggregeringar av många byggnader men samtidigt tillräckligt komplicerade för att kunna inkludera unika slutanvändarbeteenden. Detta är nödvändigt när elmarknadsaktören vill analysera hur stora volymer efterfrågeflexibilitet påverkar elmarknaden och kraftsystemen, men samtidigt förstå hur styrningen inverkar på den enskilda slutanvändaren. Bidraget från denna avhandling är botten-upp-simuleringsmodeller för generering av elförbrukningsprofiler i småhus och kontorsbyggnader. Modellerna kopplar slutanvändarbeteende med elförbrukning från apparater och varmvattenanvändning tillsammans med fysikaliska modeller av värmedynamiken i byggnaderna. Modellerna är byggda på en förenklad approach som använder öppen data och statistisk, där data som har integritetsproblem har exkluderats. Simuleringsresultat har validerats mot elförbrukningsdata från småhus och kontorsbyggnader, relaterade modeller från andra forskargrupper samt energistatistik från nationella databaser. Valideringen visar att modellerna kan generera elförbrukningsprofiler med rimlig noggrannhet. Denna avhandling är en sammanläggningsavhandling bestående av fem artiklar. Artikel 1 presenterar botten-upp-simuleringsmodellen för genereringen av elförbrukningsprofiler från uppvärmning, varmvatten och apparater i småhus. Artikel 2 presenterar ett dataanalytiskt ramverk för analys av elanvändningen från uppvärmning, ventilation, och luftkonditioneringslaster (HVAC) och apparatlaster i en kontorsbyggnad. Artikel 3 presenterar en icke-homogen Markovkedjemodell för simulering av representativa närvaroprofiler i enskilda kontorsrum. Artikel 4 använder resultaten i artiklarna 2 och 3 för att beskriva en botten-upp-simuleringsmodell för generering av elförbrukningsprofiler från HVAC-laster och apparater i kontorsbyggnader. Artikel 5 använder modellen i artikel 1 för att analysera den tekniska möjligheten att använda efterfrågeflexibilitet för att lösa överbelastningsproblem i ett eldistributionsnät.

QC 20160329

APA, Harvard, Vancouver, ISO, and other styles

49

Jacobs, Heinz Erasmus. "A conceptual end-use model for residential water demand and return flow." Thesis, 2008. http://hdl.handle.net/10210/468.

Full text

Abstract:

A conceptual end use model for residential water demand and return flow is presented in this thesis. The model requires a unique description of a single residential stand in terms of all its end-uses. The end-uses include toilet flushing, bathing and showering, garden watering, leaks, et cetera. Various parameters describe each of the end-uses. The model predicts five components relating to water demand and wastewater flow at a residence: indoor water demand, outdoor water demand, hot water demand, wastewater flow volume and concentration of solutes in the wastewater. Twelve monthly results are calculated, for each of the five components, to provide a typical seasonal pattern as well as an annual value. The large number of input parameters in an end-use model allows for powerful and detailed analysis. The parameters required to populate the model are discussed and guideline values are presented. The end-use model is used to conduct a sensitivity analysis of each independent parameter for each of the five individual model components. The elasticity and sensitivity is determined at a base point with respect to each parameter for all five results. A research significance index is also devised to integrate the elasticity and availability of data for each parameter. The result is a prioritised list of the most critical parameters for each of the five components, which are the ones that should receive the focus for future study and data recording. The parameters are combined to obtain a list of the overall most important parameters in the model for all components combined, and based on a combination of the elasticity-based rank and the sensitivity based rank. The five most important parameters are the household size, toilet flush frequency, toilet flush volume, the washing machine event frequency and the volume of leaks on a stand. The practical application of the model is illustrated. The researchers first apply the model to mimic a few commonly accepted characteristics of water demand. The effectiveness of some specific water demand management measures are evaluated by adjusting selected model parameters. The measures include xeriscaping, the installation of dual-flush toilets, low-flow showerheads, pool ownership and pool cover use. The model also enables practitioners to obtain an insight into the water use habits of homeowners. The model forms the basis for further research work in the field. Its relatively simple structure and realistic data requirement encourages its integration into existing commercially available software suites for water and sewer system analysis and -management in the civil engineering industry in South Africa, as well as abroad.
Prof. J. Haarhoff

APA, Harvard, Vancouver, ISO, and other styles

50

TingWee, Yee, and 黃儀婷. "Relationship between water and energy consumption at end use." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/04564184644454544659.

Full text

Abstract:

碩士
國立成功大學
土木工程學系
102
Energy and water are closely related to each other, yet management of the two resources has historically been independent. Energy is consumed in water supply, end use and water recycling. Previous studies found that end use consumed largest energy in the water-energy life cycle. The purpose of this study is to examine the relationship between water and energy consumption at the end-use stage. It first reviewed energy consumption at each stage in the water life cycle that helps to determine factors which increase energy consumption at water supply, wastewater, end use and water recycling. Three cases of an apartment, school and manufacturing plant were employed to analyze the correlation between water and energy consumption at end-use. The analysis results reveal that water consumption’s correlation to energy consumption increases from apartment, school to manufacturing plant. Water usage is positively related to energy consumption in the manufacturing plant. Furthermore, various end users have different factors affecting energy consumption. Factors that affect energy consumption in a manufacturing plant include distance of end users, level of treatment and pump efficiency. Meanwhile, appliance age, efficiency of water heater and pump system are factors that affect energy consumption in the apartment and school. Management can plan on water distribution based on the factors affecting energy consumption at the end use.

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'End use water models'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles