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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.
91

Interaction and Intervention a case study: 1019 Cameron Street, Alexandria, Virginia

Meadows, Craig Stuart 03 May 2004 (has links)
It is a favorite canon of preservation architects that soon 95% of work will deal with an existing construct in some manner. Reasons for this include the public's affinity toward old and historic buildings, and the utter lack of undeveloped sites in urban areas. This thesis is directed toward creating a methodology in which to define the intervention and interaction between new to existing. The general attitude toward history and existing buildings is quite divisive. Typically architects demolish existing buildings or they attempt to preserve every detail and facet of a "historical" building. The National Historic Trust, apart of the Department of Interior, provides loose guidelines with which to guide an intervention or to otherwise treat a "historic" edifice. Carlo Scarpa is one architect who has finely honed the ability to interact and intervene. / Master of Architecture
92

Beneficial Reuse of Dredged Materials in Upland Environments

Haus, Nicholas Wes 02 February 2012 (has links)
Sediments excavated from dredging operations are known as dredged materials. Beneficial reuse of dredged materials in confined utilization facilities (CUFs) is a new approach that has the potential to productively utilize large quantities of dredged materials. However, several factors can inhibit the use of dredged materials in CUFs. In this study, high levels of salts and polycyclic aromatic hydrocarbons (PAHs) were investigated. In the first part of this study, 176,000 m3 of saline dredged materials was placed into a CUF. In less than 4 years, most of the dredged materials had developed horizonation and converted to Inceptisols. The formation of pedogenic Bg horizons in these soils occurred after a polygonal prism network had developed which partially disintegrated into a blocky structured, oxidized horizon with an abundance of redoximorphic features. During the study period, the soil chemistry of the weathering dredged materials shifted from Na-dominated to Ca and Mg-dominated system, allowing plant invasion. In the second part of the study, a bench-scale greenhouse bioremediation experiment was conducted to test the effectiveness of biosolids, compost, and straw at enhancing PAH degradation. Initial concentrations of PAHs decreased significantly after 150 days using standard methods of extraction. However, at 327 days the concentrations of many PAHs, especially those with higher molecular weights, had rebounded close to initial levels. This indicates that PAH bioremediation studies using organic matter additions and conducted using standard methods of extraction need to be carried out longer periods of time or that extraction methods need to be improved. / Master of Science
93

The feasibility of utilizing grey water in Hong Kong buildings

梁雪輝, Leung, Suet-fai. January 2002 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
94

Recycled water usage in peri-urban agriculture : an examination of its socio-economic and environmental benefits in Port Elizabeth

Makinana, Anazo January 2015 (has links)
This study examines whether recycled water (specifically grey water) is used in peri-urban agriculture in greater Port Elizabeth. It also investigates the socio-economic as well as environmental benefits of using recycled water in peri-urban agriculture. Community perceptions and narratives about the use of recycled water for farming purposes were also investigated. Study respondents were purposively selected from Motherwell and Uitenhage in Port Elizabeth. A qualitative research methodology and methods were used. This involved using purposive sampling to sample, select and interview 22 respondents and eight key informants. All the respondents were interviewed using in-depth semi-structured interviews. The study found that while many respondents have heard about water recycling, they are however not using recycled grey water for their peri-urban farming activities. Instead, peri-urban farmers continue to use water supplied by the municipality. Recycled water is mostly used for watering sport fields around Port Elizabeth. This continued usage of municipal water (instead of recycled water) is not only costly to the municipality but the individual farmers as well. The respondents were however aware of the benefits of using recycled water. These include economic (money saved from not paying irrigation water bills), environmental (nutrient contents found in recycled water) and socio-economic (conserving fresh available for use in other community purposes). The study recommends that the Nelson Mandela Metro Municipality should do more (through educational and environmental campaigns) to encourage peri-urban farmers to use recycled water in their farming activities.
95

DoD Ranges Interoperability and Resource Reuse Achievable Through the Test and Training Enabling Architecture, TENA

Hudgins, Gene 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / To ensure range interoperability and range resource reuse are available and promoted across the DoD Test and Training range community, the Central Test and Evaluation Investment Program (CTEIP) has developed and continues to refine the Test and Training Enabling Architecture (TENA). TENA provides the architecture and software implementation to enable range interoperability, to foster range asset reuse, to provide composability, and to enable simulation‐based system engineering/acquisition. TENA has proven to be a critical enabler of major distributed live military exercises but has expanded to embrace other usage. Inclusive of new technologies, TENA developers are actively involved with the integrated Network Enhanced Telemetry (iNET), a CTEIP program which will provide wireless connectivity over which a variety of users will run applications and exchange data.
96

The Test and Training Enabling Architecture, TENA, Enabling Technology for the Joint Mission Environment Test Capability (JMETC) and Other Emerging Range Systems

Hudgins, Gene 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / The Joint Mission Environment Test Capability (JMETC) is a distributed live, virtual, and constructive (LVC) testing capability developed to support the acquisition community and to demonstrate Net-Ready Key Performance Parameters (KPP) requirements in a customer-specific Joint Mission Environment (JME). JMETC, using the Test and Training Enabling Architecture, TENA, provides connectivity to the Services' distributed test capabilities and simulations, and industry test resources. TENA is well-designed for supporting JMETC events through its architecture and software capabilities which enable interoperability among range instrumentation systems, facilities, and simulations. TENA, used in major exercises and distributed test events, is also interfacing with other emerging range systems, such as iNET.
97

It Takes Water and Energy in a Block

Hilmersson, Alvin, Norén, Fanny, Ullén, Alexander, Wiik, Lucas January 2016 (has links)
This report investigates sustainable solutions for electricity and water savings in an urban neighbourhood consisting of a block of buildings in Sege Park, Malmö. The solutions were evaluated in terms of sharing, producing, recycling and saving. The proposed solution includes a solar panel system on the available rooftop area for electricity production. Recycling and water savings includes collecting rainwater and reusing greywater for daily water demand in terms of flushing toilets, laundry and irrigation. Energy savings are achieved by using heat exchangers for space and water heating. Results from simulations in MATLAB and Excel showed that the electricity production reached a coverage ratioof 20% of the yearly consumption with hourly matching. However, the block has an excess electricity production, a total of 17,400 kWh, that does not correlate with the demand. Water demand for flushing toilets, laundering and irrigation during an average day can be matched by the reuse of greywater alone. Collection of rainwater is not required, although possible. The amount of reusable water, 18,540 litres a day, can cover the greywater need for three blocks equivalent to the one investigated. The conclusion is that water demand can be covered by greywater but electricity demand is too high for self-sustainability, even with the best solar panels available today.
98

Service-based automation of software construction activities

Zinn, Marcus January 2013 (has links)
The reuse of software units, such as classes, components and services require professional knowledge to be performed. Today a multiplicity of different software unit technologies, supporting tools, and related activities used in reuse processes exist. Each of these relevant reuse elements may also include a high number of variations and may differ in the level and quality of necessary reuse knowledge. In such an environment of increasing variations and, therefore, an increasing need for knowledge, software engineers must obtain such knowledge to be able to perform software unit reuse activities. Today many different reuse activities exist for a software unit. Some typical knowledge intensive activities are: transformation, integration, and deployment. In addition to the problem of the amount of knowledge required for such activities, other difficulties also exist. The global industrial environment makes it challenging to identify sources of, and access to, knowledge. Typically, such sources (e.g., repositories) are made to search and retrieve information about software unitsand not about the required reuse activity knowledge for a special unit. Additionally, the knowledge has to be learned by inexperienced software engineers and, therefore, to be interpreted. This interpretation may lead to variations in the reuse result and can differ from the estimated result of the knowledge creator. This makes it difficult to exchange knowledge between software engineers or global teams. Additionally, the reuse results of reuse activities have to be repeatable and sustainable. In such a scenario, the knowledge about software reuse activities has to be exchanged without the above mentioned problems by an inexperienced software engineer. The literature shows a lack of techniques to store and subsequently distribute relevant reuse activity knowledge among software engineers. The central aim of this thesis is to enable inexperienced software engineers to use knowledge required to perform reuse activities without experiencing the aforementioned problems. The reuse activities: transformation, integration, and deployment, have been selected as the foundation for the research. Based on the construction level of handling a software unit, these activities are called Software Construction Activities (SCAcs) throughout the research. To achieve the aim, specialised software construction activity models have been created and combined with an abstract software unit model. As a result, different SCAc knowledge is described and combined with different software unit artefacts needed by the SCAcs. Additionally, the management (e.g., the execution of an SCAc) will be provided in a service-oriented environment. Because of the focus on reuse activities, an approach which avoids changing the knowledge level of software engineers and the abstraction view on software units and activities, the object of the investigation differs from other approaches which aim to solve the insufficient reuse activity knowledge problem. The research devised novel abstraction models to describe SCAcs as knowledge models related to the relevant information of software units. The models and the focused environment have been created using standard technologies. As a result, these were realised easily in a real world environment. Softwareengineers were able to perform single SCAcs without having previously acquired the necessary knowledge. The risk of failing reuse decreases because single activities can be performed. The analysis of the research results is based on a case study. An example of a reuse environmenthas been created and tested in a case study to prove the operational capability of the approach. The main result of the research is a proven concept enabling inexperienced software engineers to reuse software units by reusing SCAcs. The research shows the reduction in time for reuse and a decrease of learning effort is significant.
99

The combined fouling of nanofiltration membranes by particulate solidsand dissolved organics in wastewater treatment and reuse

Law, Ming-chu, Cecilia, 羅明珠 January 2009 (has links)
published_or_final_version / Civil Engineering / Master / Master of Philosophy
100

A multi-criteria water quality index for optimal allocation of reclaimed municipal wastewater

Yu, John Kuo-an,1944- January 1977 (has links)
Use-oriented benefits and treatment cost analysis have been incorporated into a water quality index to derive economically optimized pollutant concentrations for use in the development of waste water treatment programs. This multi-criteria water quality index can be used in decision-making at federal and local governmental levels. Five major pollutants (coliforms, nitrogen, phosphorus, suspended solids, and detergent) were considered in the treatment of municipal wastewater. With each higher level of improvement, the treatment costs increase proportionally, but the benefits associated with the reuse of this treated wastewater also increase in all cases except that of nutrient removal for agricultural use. Listed in descending order of their general utility, possible uses of reclaimed water include water supply, recreation, irrigation, industrial use, waste disposal, transportation, and commercial fishery. The optimal concentration of a pollutant was defined as that point at which the marginal costs of its removal equal the marginal benefits thereby obtained. The optimum net benefits associated with each kind of reclamation are derived simultaneously. The multicriteria water quality index is a combination of the maximum net benefits and the water quality index of the optimal individual concentrations. Walski and Parker's water quality index was used in rating water quality. This methodology was applied to the Tucson region for the expediency of acquiring data. Possible uses considered for the reclaimed municipal wastewater included agricultural irrigation and recreational lakes in the Tucson metropolitan area. Results from this study indicate that the multi-criteria water quality index is zero dollars, or (NB = $1.83•10⁶, WQI = 0). Similar evaluations for other cities, made in the same way, would permit ranking of this index. This ranking would be useful for making decisions concerning the allocation of regional funds for treating municipal wastewater. This approach could also be used on a local level for determining optimal concentrations of pollutants and for optimal allocation of the treated water.

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