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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.
11

Chitobiase as a tool in water quality monitoring

MacKenzie, Scott 11 March 2016 (has links)
Time-consuming and expensive benthic surveys are currently the most common means of determining impacts on invertebrates and fish habitat in lotic systems. We propose using the rate of chitobiase production by benthic invertebrates as a complement for determining impacts on freshwater systems. We successfully modified the existing assay to a microplate approach for high throughput analysis of chitobiase activity. Next we conducted two case studies in: 1) the Dead Horse Creek, Manitoba, to determine if changes in chitobiase could detect impacts on the benthic community from wastewater effluent and; 2) in Snake and Kinch Creeks, Manitoba to see if chitobiase could be used to assess fish habitat quality. In both cases, we observed no strong relationships between chitobiase and traditional metrics (e.g., abundance, biomass, diversity). We recommend further studies concerning the timing of chitobiase release in lotic systems and assessments of its use in mesocosm and microcosm toxicity studies / May 2016
12

The Design of a DSP Based Power Quality Monitoring Device

Lin, Jin-Yi 03 July 2001 (has links)
Electric power utilities and end users are becoming increasingly concerned about the quality of power supply. To reduce the losses caused by power service disturbances, mitigation devices are available for improving the power quality. The first step in the power quality improvement is to monitor the system behavior by using some Electronic recording devices. A design and implementation of a digital signal processor based power quality monitoring device is presented in this thesis. Several event-triggering methods are studied and implemented to detect system disturbances. Simulation and test results indicate that the proposed design can meet the requirements for power measurements and transient event recording during steady and transient states.
13

A critical review of Hong Kong air quality data /

Ip, To-yan, Francis. January 2001 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (p. [84-85]).
14

A mathematical procedure for air monitoring instrumentation location

Lee, Thomas Davis 08 1900 (has links)
No description available.
15

Study of air-borne polycyclic aromatic hydrocarbons in El Paso, TX

Santiago, Lynn Marie, January 2008 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
16

Application of cluster analysis to identify sources of particulate matter in Hong Kong /

Chan, Sik-foon, Joyce. January 1995 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references.
17

Chance constrained models for air pollution monitoring and control /

Lelas, Vedran, January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 226-244). Available also in a digital version from Dissertation Abstracts.
18

Participatory Air Quality Monitoring System

Choi, Daeyoung 08 September 2010 (has links)
No description available.
19

Site Selection for Air Pollution Monitoring in the Vicinity of Point Sources

Brown, John C. 01 January 1978 (has links) (PDF)
Ever since air pollution became a national concern in the 1950's, more and more emphasis has been placed on collection of representative air samples for many purposed, to include (1) evaluation of the degree to which national ambient air quality standards are being met and (2) to monitor maximum emission levels from point sources. Until recently efforts were directed toward qualitative methods of siting monitors for representative sampling. Since the dispersion of effluents is most complex, the quality of the data collected on the basis of judgment and, more or less, incremental siting about the source, has become suspect. Furthermore, with the increasing demands for monitoring due to international growth in network monitoring systems, amendments to the Clean Air Act and the legislation on the Prevention of Significant Deteoriation of Air Quality, it is not cost-effective to encircle point sources with large numbers of equally spaced monitors. This paper discussed the history of air pollution concerns that have resulted in the need for monitoring; the development of siting techniques through largely qualitative measures; and finally, summarizes three quantitative methodologies for monitoring point sources. Emphasis is placed on the methodology developed by Noll, et al., (1977), based on the author's belief that this methodology represents the state of the art.
20

Projeto e avaliação de desempenho de redes de monitoramento de qualidade da água utilizando o conceito de entropia.

Soares, Paulo Fernando 24 July 2001 (has links)
A manutenção da qualidade ambiental está diretamente relacionada ao conhecimento e controle das variáveis que interferem no problema, sejam elas resultantes das ações do homem sobre o ambiente ou de suas transformações naturais. Este conhecimento sobre o meio ambiente pode ser obtido através de monitoramento e, no caso dos corpos d’água, a eficácia do monitoramento depende em especial de um projeto e operação adequados do sistema de informações, que é constituído pela aquisição, manipulação, análise e utilização da informação obtida. No que se refere à aquisição da informação, ainda existem grandes lacunas a serem preenchidas na decisão sobre onde, quando e o que monitorar. Neste trabalho são enfocadas as atividades básicas do projeto da rede de monitoramento, ou seja, a localização das estações, a seleção das variáveis, a freqüência e a duração da amostragem, procurando-se buscar um conjunto de diretrizes de aplicação que seja exeqüível e eficaz para o projeto e manutenção de redes de monitoramento, uma vez que não se dispõe atualmente na literatura, de procedimento geral que vise solucionar este problema. A localização das estações de monitoramento na bacia hidrográfica, denominada de macrolocalização, a determinação de freqüências amostrais e a definição das variáveis a serem monitoradas, são tarefas que fazem parte do projeto da rede de monitoramento da qualidade da água. A rede de monitoramento, por sua vez, é parte do sistema de informações sobre qualidade da água, cujo objetivo é a descrição dos fenômenos físicos, químicos e biológicos relacionados à qualidade do corpo d’água. A eficiência da metodologia discutida neste trabalho é demonstrada e discutida através de estudos de casos. Dentre as contribuições deste trabalho podem-se destacar: (i) a ampliação do trabalho de POMEROY e ORLOB, para a localização de estações de monitoramento baseando-se na área e características de drenagem da bacia hidrográfica; (ii) a adaptação do procedimento de otimização no processo de macrolocalização de SHARP; (iii) a dedução da equação da entropia para análise de múltiplas variáveis; (iv) o desenvolvimento de um aplicativo computacional para a análise e avaliação de desempenho de estações de monitoramento baseado no conceito de entropia; e (v) a proposição de uma metodologia geral de dimensionamento e redimensionamento de redes de monitoramento de qualidade da água . Neste trabalho são descritas, discutidas e aplicadas as metodologias disponíveis para a macrolocalização e as recentemente propostas para o redimensionamento de redes de monitoramento, baseadas no conceito de entropia, objetivando a produção de diretrizes de projeto de redes de monitoramento, especialmente para países em desenvolvimento. Assim sendo, neste trabalho não se faz somente uma análise de métodos disponíveis para o projeto de redes de monitoramento mas também é proposta uma metodologia de dimensionamento e redimensionamento de redes de monitoramento para bacias com poucos dados e para bacias com dados de qualidade da água. Desta forma espera-se contribuir com países em processo de início e organização de seus sistemas de informação ambiental, e também para aqueles com suas redes já em operação, facilitando-se a decisão quanto à destinação de recursos para a adequação da realidade financeira aos objetivos de operação e manutenção destes sistemas. / The maintenance of the environmental quality is directly related to the knowledge and control of the variables affected by the problem, either as a result of the human action on the environment, or due to natural transformations. Knowledge on the environment can be obtained through monitoring. The effectiveness of the monitoring especially depends on the project of the information system and its operation. Data acquisition, manipulation, analysis, as well as the use of the generated information, are all activities that must be prepared by the project. As far as the acquisition of information is concerned, there are research gaps about the decision on where, when and what to monitor. This study will focus on the basic activities of the monitoring network project, that is, the location of the stations, the variable selection and the sampling frequency. The objective is to find out a group of application guidelines that has a practical use and is effective both to the project and maintenance of monitoring networks, since a general procedure to solve this problem is not available in the literature. Water quality monitoring networks are part of the water resources information system, with the objective of describing the physical, chemical and biological phenomena related to the quality of the water body. The efficiency of the methodology discussed in this study is demonstrated and discussed through case studies. The most important contributions of this study are: (i) the expansion of the POMEROY and ORLOB studies to locate monitoring stations based on the watershed area and channel network; (ii) the extended use of the optimization procedure proposed by SHARP to improve the macrolocation process; (iii) the deduction of the entropy equation to analyze the multiple variables; (iv) the software to analyze and to propose a new design for monitoring networks, based on the entropy concept; and (v) the proposal of a general methodology to the water quality monitoring network design and redesign. The processes and methodologies proposed in this study were developed to be applied in developing countries. Usually such countries are in the process of initialization and organization of their environmental information systems, and we hope that this study will be able to bring satisfactory benefits, taking into account that optimization is necessary to bring the costs down and to make the monitoring effort sustainable.

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