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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Numerical and Experimental Study of Droplet-Air Flow Interaction on the GDL Surface of PEMFC for Water Management Monitoring, Control and Diagnostics

Esposito, Angelo 30 August 2010 (has links)
No description available.
332

Water Management as a Tool to reach Sustainable Peace; The Case of Israel and Syria

Heise, Aline January 2010 (has links)
In my thesis essay I have researched the impact of water management on the outcome of peace negotiation and treaty in the case of Israel and Syria. My research question was “How should the water resources of the Golan Heights be addressed in a coming peace treaty between Israel and Syria for this treaty to be sustainable?”. I emanated from the theory advocated by researchers Ohlsson, Homer-Dixon and Gleick, arguing that the detailed incorporation of water management in negotiations as well as in a final peace treaty between countries is crucial for these to be sustainable. I used this theory in analysing the extended data related to the two countries’ water resources and water policies, as well as two previous rounds of negotiation. I came to the conclusion that for any future negotiation to lead to a sustainable peace agreement between the two countries, it is crucial for them to establish very detailed stipulations on the shared water resources. Both Israel and Syria are in great need of accessing and controlling water resources, however Israel is much more dependent than Syria on the waters of the Golan Heights. When an internationally recognized borderline between the countries in the future will be established, it will by default be situated on or closely connected to vital water resources. Therefore the water management, including use of and withdrawal from these resources needs to be clearly regulated, otherwise conflict might rise again between the two countries. If water management would be included in the peace treaty in as thoroughly manner as the theorists suggests, this would enable the treaty to become sustainable, as well as make feasible the resolution of related conflicting matters.
333

Evaluation of the Effect of Microporous Sublayer Design and Fabrication on Performance and Adhesion in PEM Fuel Cell Assemblies

Henderson, Kenneth Reed 20 October 2005 (has links)
The typical architecture of the proton exchange membrane fuel cell (PEMFC) contains a layer called the microporous sublayer (MSL). The MSL is a mixture of carbon black and polytetrafluoroethylene (PTFE), which is typically applied to the gas diffusion layer (GDL). The composition (wt.% PTFE) and loading (mg/cm2) can be varied to optimize the electrochemical performance of the PEMFC and the overall adhesion of the layers within the PEMFC. This research establishes correlations that characterize the performance and adhesion of the layers within the PEMFC based on composition, loading, fabrication pressure, and fabrication time. MSL loading was varied from 1.5-4 mg/cm2, composition was varied from 10-50 wt.% PTFE, fabrication pressure was varied from 3.45-10.34 MPa, and fabrication time was varied from 2-8 minutes. Using these four factors, correlations were created, and optimal solutions for each response were identified. The adhesion correlation identifies a low MSL loading, mid-range MSL composition, high fabrication pressure, and high fabrication time as desirable factors. The performance correlation suggests that the PEMFC performance is enhanced with low MSL loadings, low MSL PTFE content, and a low fabrication pressure and does not find fabrication time to be a significant factor in the correlation. / Master of Science
334

Water, Conflict, & Cooperation: Ramallah, West Bank

Amjad, Urooj Quezon 08 April 2000 (has links)
Conclusions of this case study on Ramallah imply that an effective water management strategy will have a dual intent: incorporate "trickle-up" municipal level water management strategies and integrate conflict reduction measures. This study finds that Ramallah's cooperation with the Palestinian Authority and environmental Non-governmental organizations has a strong influence on water management and water conflict alleviation. Palestinian municipal and regional water management processes, can potentially contribute to effective water management and water conflict reduction between Israelis and Palestinians. The study focuses on Ramallah, a centrally located, mid-sized town in the West Bank. This research uses interviews of Palestinian water managers and researchers, gathered in the West Bank throughout the summer of 1999, as well as secondary sources. / Master of Urban and Regional Planning
335

User interactions in strategic research: The example of two UK 'Integrated Urban Drainage Pilots'

Sharp, Liz January 2008 (has links)
No / According to Lowe and Phillipson (2006) the traditional binary division into `basic¿ and `applied¿ research, have recently been extended to a new category called `strategic¿ research, signifying research which is both inter-disciplinary and interacts with research users. Sharp and Dixon (2007) have argued that there are different level of strategic research, signifying different levels of interaction, resource sharing, and joint development of outputs. Drawing on this understanding, this paper considers two user-oriented `Integrated Urban Drainage¿ pilot projects conducted during 2006-7, in order to consider what insights these `not-quite¿ research projects can yield about the nature of strategic research. The paper finds that the pilots were similar to other inter-disciplinary research projects ¿ except that they were commissioned and partly managed by practitioners. Common dilemmas, for example about the inter-linkages between work packages and about the extent of stakeholder interaction, highlight the increasingly fluid boundaries between the categories of `policy evaluation¿, `policy pilot¿ and `research project¿. The paper concludes that the concepts of `researcher¿ and `research user¿ might be replaced with a more flexible idea about `research stakeholders¿ whose varied interests in projects require a flexible communication strategy to fulfil a range of needs.
336

Collaborative research in sustainable water management: issues of interdisciplinarity.

Dixon, J., Sharp, Liz January 2007 (has links)
No / This paper reflects on what is meant by interdisciplinary engagement in the context of two integrated urban water management research programmes in the UK and New Zealand. Different extents of interdisciplinary engagement in research teams are conceptualised on a continuum that ranges from rhetorical intentions to joint research. We discuss how interdisciplinary working in research programmes is shaped through the processes of bidding, research management and production of outputs. The paper concludes that if higher levels of interdisciplinarity are desired, they need to be specifically funded and planned for. In particular, funders may need to provide flexibility in relation to interdisciplinary outputs, which may be hard to specify at the start of a research programme.
337

Analyse eines urbanen Gewässereinzugsgebietes als Planungsgrundlage nachhaltiger Wasserbewirtschaftung am Beispiel der Wuhle im Raum Berlin

Ertl, Christoph 18 December 2007 (has links)
Die genaue Kenntnis über den Wasserhaushalt stellt die Grundlage für die Bewirtschaftung der Ressource Wasser dar. Im urbanen Raum spielen dabei die siedlungshydrologischen Randbedingungen, wie Versiegelung, Anschlussgrad an die Kanalisation oder wasserbauliche Eingriffe, eine nicht zu vernachlässigende Rolle. Zur Quantifizierung der verschiedenen Wasserhaushaltsgrößen wurde ein konzeptioneller Ansatz entwickelt, der die jeweiligen Randbedingungen berücksichtigt und deren gegenseitige Beeinflussung abbildet. Hierbei muss der Einfluss auf den Wasserhaushalt auch bei veränderten Bedingungen simulierbar sein. Als Untersuchungsgebiet wurde das Gebiet der Wuhle, ein rechter Nebenfluss der Spree, gewählt, da es alle relevanten Aspekte der Wasserwirtschaft beinhaltet. Die Wuhle entspringt auf der Barnim-Grundmoränenhochfläche bei Ahrensfelde und mündet nach etwa 15,7 km Lauflänge im Stadtteil Köpenick in die Spree. Der Ansatz beruht auf der Berechnung der Wasserhaushaltsgrößen mit Hilfe eines flächendifferenzierten Verfahrens zur Ermittlung des Gesamtabflusses aus Niederschlag abzüglich der Verdunstung sowie dessen Aufteilung in einen oberirdischen und einen unterirdischen Teil. Zur Verifizierung der wasserhaushaltlich bestimmten Abflussgrößen wurden detaillierte hydraulische Untersuchungen an der Wuhle durchgeführt und abschnittsweise interpretiert. Anschließend wurde mit Hilfe der Förderdaten der Wasserwerke eine Grundwasserhaushaltsbilanz durchgeführt. Im Ergebnis ließ sich hydrogeologisch der Anteil an Uferfiltrat an der Gesamtfördermenge ermitteln. Zur Simulation des Einflusses des Wasserhaushaltes und der Grundwassernutzung auf den Grundwasserkörper wurde mit Hilfe des Simulators FEFLOW© eine numerische Modellierung der Strömungsverhältnisse durchgeführt. Über den Abgleich der simulierten Grundwasserhöhen mit den Grundwasserständen aus der Stichtagsmessung erfolgte eine zusätzliche Überprüfung der wasserhaushaltlich berechneten Abflussgrößen. / The exact knowledge of the water balance is the basis of the water supply and distribution within a catchment area. In an urban area the boundary conditions of the civil engineering like the sewer system or the hydraulic engineering plays an important role. To quantify the water balance a conceptual approach was developed which takes the current conditions and their interdependence into consideration. The impact of changing conditions on the water balance can also be simulated. As investigation area the catchment of the Wuhle River was chosen because it includes all relevant aspects of water management. The Wuhle River has its source on the ground moraine of the Barnim plateau directly at the city boundary in Ahrensfelde and reaches the Spree in the quarter Köpenick after about 15.7 km. This method uses a differentiated calculation by area to determine the total outflow of rainfall minus evaporization. It also determines the submontane and aboveground distribution. For verification purposes detailed hydraulic investigations were carried out at the Wuhle. With the production rate of the waterworks the groundwater balance was then calculated. As a result the amount of bank filtrate of the total groundwater withdrawal was determined in a hydro geological way. Using the simulation software FEFLOW© a numeric model of the flow pattern was created to simulate the influence on the water balance and the groundwater. The displayed subterranean catchment area of the water work Wuhlheide was based on the water table contours which were interpolated from a fixed date measurement of the groundwater heads. By comparing the simulated groundwater heads and the water levels from the fixed date measurement an additional verification of the water balance was realised.
338

Water Harvesting for Integrated Water Resources Management and Sustainable Development in Khartoum State

Hassan Mahmoud, Wifag 21 October 2013 (has links) (PDF)
Khartoum State in Sudan is subject to the erratic and intense rainfall during the short rainy season and dryness and heat throughout the rest of the year. High intensity rainstorms with a short duration have become more frequent in the area during the last two decades resulting in cities inundation and flash floods in the rural parts. On the other hand, the dry season means hot weather in the urban parts and water shortage in the rural part. Rural areas are dependent on the runoff water brought about by the seasonal streams as a source of water. For this study, Khartoum City Center and Seleit area were taken to investigate the application of water harvesting in the urban and rural areas, respectively. Accordingly, the hydrological characteristics and the specification of the potential water harvesting sites and systems were examined. For Khartoum City Center, characteristics of the drainage system were examined using ArcGIS platform. It is found that the drainage system covers 42% of the area with total capacity of 24000 m3. Daily rainfall data for urban meteorological station were used to calculate the probability and the return period of the rainfall, as well as the potential runoff. Rainfall probability of occurrence was calculated applying Gumbel distribution method for extreme events that were arranged according to the Peak-over-Threshold method. The potential runoff that could be generated from a certain rainfall was calculated using the Natural Resources Conservation Services method provided by the United States Department of Agriculture (US-NRCS). Accordingly, the curve number was calculated depending on the land use/land cover and the hydrological soil group. Consequently, the weighted curve number is found to be 94%, indicating dominant imperviousness. 13.1 mm rainfall depth produces runoff volume equal to the drainage system capacity with return period of one year; whereas more than four folds the drainage system capacity is produced by 30 mm rainfall depth that is considered the threshold for raising flood hazard. Six potential sites for roof rainwater harvesting were selected. Accordingly, it is found that, the application of roof water harvesting in 18% and 72% of the commercial and business district buildings can accommodate the runoff resulting from the 13.1 and 30 mm rainfall depth, respectively. Hence, impounding rainstorm water would help managing the urban runoff water, and consequently, the stored water could be used for making more green areas that will enhance the urban environment. Three watersheds of ephemeral streams (wadi), namely Wadi El Kangar, Wadi El Seleit, and Wadi El Kabbashi make up Seleit area. Distinct maps were prepared in ArcMap for the calculation of the potential runoff and the specification of the appropriate water harvesting sites and systems. The Wadis watersheds areas are found to be 540, 344 and 42 km2 for Wadi El Kangar, Wadi El Seleit and Wadi El Kabbashi, respectively. Daily rainfall data of rural meteorological station were classified into three groups representing the soil dry (AMCI), moderate (AMCII), and wet (AMCIII) moisture conditions; the respective CNI, CNII, and CNIII values were calculated accordingly. The weighted CN values indicate high runoff potential within the three soil moisture conditions. Accordingly, the rainfall thresholds for runoff generation for AMCI, AMCII and AMCIII conditions are found to be respectively 18.3 mm, 9.1 mm and 4.4 mm for Wadi El Kabbashi and 22 mm, 11 mm and 5 mm for both Wadi El Seleit and Wadi El Kangar. El Kangar dam subwatershed was used for calibrating the potential runoff calculated by the NRCS method. Since the Wadis are ungauged, Google Earth and GIS platforms were used to calculate geometrically the volume of the dam reservoir water for three years. This volume was compared to the annual runoff calculated by the NRCS method. Consideration to different factors was made to locate the potential water harvesting sites. Accordingly, water harvesting systems for fodder and crop plantation; sand storage surface or subsurface dams; or groundwater recharge, were specified. The socio-economic study revealed that the financial capacity, if any, of the villagers is very limited. Thus, the financial source for the construction of the suggested potential water harvesting or the rehabilitation of the existing ones is questionable. Hence, other potential financial sources are needed to help executing water harvesting projects in the region, e.g. Khartoum State Government. Applying water harvesting in Seleit area is found to be promising. Improving the livelihood of the villagers by applying runoff water harvesting could assure better water accessibility, better income generation from farms production, and allocation of time for other activities, e.g. education. This would be reflected in reduced migration to nearby cities and stabilized market supply of agricultural and animal products. Therefore, the development of the rural part is of great benefit to the development of Khartoum State, as long as the interdependency and mutual benefit between the rural and urban areas, represented by the local food and labor market, remain exist.
339

Analysis of the cost effectiveness of alternative policies and technologies to manage water extractions by the oil sands sector along the lower Athabasca River

Mannix, Amy Elinor Unknown Date
No description available.
340

Analysis of the cost effectiveness of alternative policies and technologies to manage water extractions by the oil sands sector along the lower Athabasca River

Mannix, Amy Elinor 11 1900 (has links)
The Lower Athabasca Water Management Framework limits water extractions by the oil sands industry near Fort McMurray, Alberta. To increase water-use efficiency and minimise the cost of water restrictions, several policy and technology options were developed and assessed using quantitative and qualitative methods. Selected options were the policies of water trade and pricing with refund, and the technologies of storage, and consolidated tailings and increased recycling. Options were designed based on year 2020 demand and assessed relative to prior allocation. Using linear programming and static optimisation, it is shown that an off-stream storage sized to avoid water restrictions, in combination with efficient water allocation (e.g. water trade), is most cost-effective, although provides no ongoing incentive to increase water-use efficiency. Only the policy options provide equal incentives across firms to increase efficiency. To achieve both objectives of increased water-use efficiency and minimised costs, a combined policy and technology approach is recommended. / Agricultural and Resource Economics

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