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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.
51

A review of the fluvial geomorphology monitoring of the receiving streams of the Mooi-Mgeni [River] Transfer Scheme Phase 1 /

Hunter, Alistair Malcolm Scott. January 2009 (has links)
Thesis (M.Env.Dev.) - University of KwaZulu-Natal, Pietermaritzburg, 2009. / Full text also available online. Scroll down for electronic link.
52

Spatial monitoring of natural resource condition in Southern Africa /

Van der Merwe, Joseph Petrus Albertus. January 2005 (has links)
Thesis (MSc)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
53

Monitoring land use and land cover changes in Belize, 1993-2003 a digital change detection approach /

Ek, Edgar. January 2004 (has links)
Thesis (M.S.)--Ohio University, August, 2004. / Title from PDF t.p. Includes bibliographical references (p. 98-101)
54

Rights Holders, Stakeholders, and Scientists: A Political Ecology of Ambient Environmental Monitoring in Alberta, Canada

Thill, Zackery 06 September 2018 (has links)
States increasingly rely on ambient environmental monitoring systems to provide information on environmental conditions in order to make science-based decisions on resource management. This kind of monitoring relies on a network of state and intergovernmental agencies to generate indexes, thresholds, and indicators to assess the status of air, water, and biodiversity. As a result, these thresholds and indexes generate representations of environmental change, and they establish acceptable limits on pollution. However, in settler states like Canada, there are often major gaps in how First Nations experience environmental change compared to the agencies that produce the science. In recent years, monitoring has taken on a new importance because the findings from these agencies contribute to understanding how industrial development impacts First Nations’ treaty rights. Many First Nation communities have called for greater say in government agencies and have advocated for indicators that represent both their basic environmental concerns and their treaty rights. Using oil sands monitoring agencies as a lens, this dissertation examines the politics of environmental knowledge production between Indigenous groups and the state. I employ the “logic of elimination” concept from settler colonialism studies to explore the extent to which Indigenous groups have been incorporated in research design, decision-making, and the establishment of environmental thresholds. I use interviews, participant observation, and a Q-method survey to develop an understanding how settler colonialism functions not only through policies and legislation, but also scientists’ positionalities. The findings from this research demonstrate that monitoring agencies have no uniform policies to guide how they work with First Nations. Because of this, agencies have continually engaged with First Nations as stakeholders—not rights holders. This designation places First Nations on the same level as other interest groups and limits their abilities to shape what is monitored and how thresholds are set. As a result, the stakeholder position offers few avenues for First Nations to ensure treaty rights are considered in monitoring activities. / 10000-01-01
55

Imagens multitemporais ALOS/PALSAR baseada em orientação a objeto na discriminação da cobertura da terra

Beneditti, Cristina Aparecida [UNESP] 30 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-30Bitstream added on 2014-06-13T19:07:52Z : No. of bitstreams: 1 beneditti_ca_me_prud.pdf: 3065249 bytes, checksum: b10d04069c7a91011443ee9fcf72ab9c (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Sensores ópticos são amplamente utilizados para mapeamento da cobertura da terra em escala local e pequenas regiões, com uma ampla variedade de aplicações, incluindo planejamento urbano, inventario agrícola e florestal, gerenciamento de bacias hidrográficas e monitoramento ambiental. Mapeamento de cobertura da terra com dados da banda L SAR tem focado primariamente em florestas e área úmidas de regiões tropical e boreal, com ênfase no monitoramento de desmatamento tropical e reflorestamento. No inicio de 2006, aquisições sistemáticas do ALOS PALSAR tem fornecido conjunto de dados multisazonais com alta resolução (12,5m), com potencial para substituir ou complementar os conjuntos de dados ópticos para mapeamento de cobertura da terra em regiões que a cobertura de nuvens é menos problemática, mas ainda um limitante para a variação sazonal da cobertura da terra. Este estudo avalia a utilização de dados PALSAR multitemporal, combinados com modelo digital de superfície (DSM) derivado do ALOS PRISM, para o mapeamento da cobertura da terra em uma região central do estado de São Paulo, Brasil. A área de estudo (22.5ºS 47.8 ºW) está situada na região oeste do reservatório de Barra Bonita, próximo a confluência dos rios Tietê e Piracicaba, com elevações variando entre 300 e 1000m. Os usos da terra dominante são agricultura ( cana de açúcar, cítricas e gramíneas) e florestal (eucaliptos). A vegetação natural é restrita a vegetação riparia, mata na front da cuesta e macrofitas aquáticas sazonais. Áreas urbanas presente na região são São Pedro e Aguas de São Pedro. Duas cenas PALSAR no modo Fine-Beam Single-polarization (FBS) (08 de abril de 2008 e 09 de janeiro de 2009... / Optical sensors are widely used for land cover mapping at local and small region scales, for a wide variety of applications including urban planning, forest and crop inventory, watershed management, and environmental monitoring. Land cover mapping with L-band SAR data has focused primarily on forest and wetland areas in tropical and boreal regions, with particular emphasis on monitoring tropical deforestation and regrowth. Beginning in 2006, systematic acquisitions of ALOS PALSAR have provided multi-season, near-global data sets at high (12.5 m) resolution, with the potential to substitute for or complement optical data sets for land cover mapping in regions where cloud cover is less problematic, but still limiting for seasonally varying land cover. This study evaluates the utility of multi-temporal PALSAR data, combined with a digital surface model (DSM) derived from ALOS PRISM, for land cover mapping at a site in central São Paulo state, Brazil. The study area (22.5ºS 47.8 ºW) is situated at the west end of the Barra Bonita Reservoir, at the entrance point of the Tietê River, with elevations ranging from about 300 to 1000 m. Dominant land uses are agriculture (sugar cane, citrus, pasture) and forestry (eucalyptus). Natural vegetation is largely restricted to riparian forest, forests on steep slopes, and seasonal aquatic macrophytes. Urban areas include the cities of São Pedro and Águas de São Pedro. Two PALSAR Fine-Beam Single-polarization (FBS) mode scenes (8 April 2008 and 9 January 2009... (Complete abstract click electronic access below)
56

Automated Monitoring for Data Center Infrastructure

Jafarizadeh, Mehdi January 2021 (has links)
Environmental monitoring using wireless sensors plays a key role in detecting hotspots or over-cooling conditions in a data center (DC). Despite a myriad of Data Center Wireless Sensor Network (DCWSN) solutions in literature, their adoption in DCs is scarce due to four challenges: low reliability, short battery lifetime, lack of adaptability, and labour intensive deployment. The main objective of this research is to address these challenges in our specifically designed hierarchical DCWSN, called Low Energy Monitoring Network (LEMoNet). LEMoNet is a two-tier protocol, which features Bluetooth Low Energy (BLE) for sensors communication in the first tier. It leverages multi-gateway packet reception in its second tier to mitigate the unreliability of BLE. The protocol has been experimentally validated in a small DC and evaluated by simulations in a midsize DC. However, since the main application of DCWSNs is in colocation and large DCs, an affordable and fast approach is still required to assess LEMoNet in large scale. As the first contribution, we develop an analytical model to characterize its scalability and energy efficiency in a given network topology. The accuracy of the model is validated through extensive event-driven simulations. Evaluation results show that LEMoNet can achieve high reliability in a network of 4800 nodes at a duty cycle of 15s. To achieve the network adaptability, we introduce and design SoftBLE, a Software-Defined Networking (SDN) based framework that provides controllability to the network. It takes advantages of advanced control knobs recently available in BLE protocol stacks. SoftBLE is complemented by two orchestration algorithms to optimize gateway and sensor parameters based on run-time measurements. Evaluation results from both an experimental testbed and a large-scale simulation study show that using SoftBLE, sensors consume 70% less power in data collection compared to those in baseline approaches while achieving the Packet Reception Rate (PRR) no less than 99.9%. One of its main steps of DCWSN commissioning is sensor localization, which is labour-intensive if is driven manually. To streamline the process, we devise a novel approach for automated sensor mapping. Since Radio Frequency (RF) alone is not a reliable data source for sensor localization in harsh and multi-path rich environments such as a DCs, we investigate using non-RF alternatives. Thermal Piloting is a classification model to correlate temperature sensor measurements with the expected thermal values at their locations. It achieves an average localization error of 0.64 meters in a modular DC testbed. The idea is further improved by a multimodal approach that incorporates pairwise Received Signal Strength (RSS) measurements of RF signals. The problem is formulated as Weighted Graph Matching (WGM) between an analytical graph and an experimental graph. A parallel algorithm is proposed to find heuristic solutions to this NP-hard problem, which is 30% more accurate than the baselines. The evaluation in a modular DC testbed shows that the localization errors using multi-modality are less than one-third of that of using thermal data alone. / Thesis / Candidate in Philosophy
57

Nanomaterials-based electrochemical sensors for health and environmental monitoring

Ali, Md Younus January 2023 (has links)
Bisphenol A (BPA), an endocrine disruptor, requires monitoring in water for health safety. Glutamate, H2O2, and glucose are vital biomarkers for various diseases. However, lab-based methods are expensive, time-consuming, and require skilled personnel, making them unsuitable for point-of-care (POC) devices. The electrochemical sensor enables POC device development. However, it suffers from low sensitivity and selectivity. This thesis focuses on the use of nanomaterials to enhance the sensitivity and selectivity of electrochemical sensors to monitor BPA in water, along with glutamate, H2O2, and glucose in bio-fluids. A BPA sensor was developed using chemically modified MWCNTs with βCD on a screen-printed carbon electrode (SPCE). The MWCNTs-βCD/SPCE exhibited high sensitivity, attributed to the catalytic activity of MWCNTs and the host-guest interaction ability of βCD. It provided a linear range (LR) of 125 nM −30 µM, with a limit of detection (LOD) of 13.76 nM (SNR = 3). We improved the performance by curing the MWCNTs-βCD/SPCE with CTAB. The sensor demonstrated a dynamic range of 500 fM to 10 μM, with a LOD of 96.5 fM, surpassing the Canada-assigned PNEC of BPA in water (0.77 nM). We fabricated a nonenzymatic glutamate sensor using CuO nanostructures and MWCNTs on SPCE. The sensor showed irreversible oxidation of glutamate involving one electron and one proton, and an LR of 20 μM−200 μM with LOD of 17.5 μM and sensitivity of 8500 μAmM−1cm−2. The sensor is promising to detect glutamate in blood. We developed a nonenzymatic glucose sensor using green synthesized gold nanoparticles and CuO-modified SPCE. The LR offered by the sensor (2 µM to 397 µM) is suitable for quantifying saliva glucose. We also created nonenzymatic H2O2 sensor by green synthesized silver nanoparticles modified SPCE which offers LR of 0.5- 161.8 µM with LOD 0.3 µM which is capable of H2O2 monitoring in urine. / Thesis / Doctor of Philosophy (PhD) / Bisphenol A (BPA) is a plastic pollutant and an endocrine-disrupting chemical that causes reproductive and neurodevelopmental disorders, and many diseases including obesity, diabetes, and cardiovascular disease. In addition, glutamate, hydrogen peroxide (H2O2), and glucose are vital biomarkers for various acute and chronic diseases. These diseases impose significant burdens on individuals, healthcare systems, and the economy. Therefore, they must be monitored. In this thesis, we developed a BPA sensor using chemically modified multiwall carbon nanotubes (MWCNTs) with β-cyclodextrin (βCD) and cetrimonium bromide (CTAB) which can detect BPA at very low concentration beyond Canada-assigned predicted-no-effect-concentrations (PNEC) of BPA. We also developed a glutamate sensor using MWCNTs and wet chemically synthesized copper oxide (CuxO) nanostructure which offers a linear range related to blood glutamate level. Moreover, we fabricated nonenzymatic H2O2 and glucose sensors using green synthesized gold (AuNPs) and silver (AgNPs) nanoparticles (using orange peel extraction as a reducing and stabilizing agent) which are useful to quantify urine H2O2 and saliva glucose respectively.
58

A prevention of significant deterioration case study

Astruc, Salud 05 September 2009 (has links)
The PSD permitting of new sources has drawn increasing public and governmental opposition. Much of the opposition is due to heightened environmental awareness. The issues are further compounded by inherent obstacles resulting from the PSD regulations and guidelines. A chronological review of the process used by Old Dominion Electric Cooperative to obtain a PSD permit is presented to demonstrate the major PSD permitting issues facing new developers. The issues include the appropriate methodology for Best Available Control Technology determination, protocol to be used for air quality analysis, the best way to handle the Federal Land Manager's current concerns, and public participation. The present case study is analyzed to develop suggestions that would improve the current PSD process without jeopardizing the integrity of the program. Additionally, recommendations are made for developers who may encounter similar obstacles. / Master of Science
59

Zebra GC: A Fully Integrated Micro Gas Chromatography System

Garg, Apoorva 29 August 2014 (has links)
A ready-to-deploy implementation of microfabricated gas chromatography (microGC) system characterized for detecting hazardous air pollutants (HAPs) at parts-per-billion (ppb) concentrations in complex mixtures has been described. A microfabricated preconcentrator (microPC), a MEMS separation column with on-chip thermal conductivity detector (microSC-TCD), the flow controller unit, and all the necessary flow and thermal management as well as user interface circuitry are integrated to realize the fully functional microGC system. The work reports extensive characterization of microPC, microSC and micro]TCD for target analytes: benzene, toluene, tetrachloroethylene, chlorobenzene, ethylbenzene, and p-xylene. Limit of Detection (LOD) of ~1 ng was achieved, which corresponds to 10 min sampling time at a flow rate of 1 mL/min for analyte present at ~25 ppbv concentration. An innovative method for generating very sharp injection plugs from the microPC even in the presence of flow sensitive detectors like micro]TCD is described. A one-to-one comparison between microGC system and conventional Automated Thermal Desorption-Gas Chromatograph-Flame Ionization Detector (ATD GC-FID) system for real gasoline samples in simulated car refueling scenario is reported. / Master of Science
60

The lichen flora of Hull, with particular reference to zonal distribution and environmental monitoring

Seaward, Mark R.D. January 2004 (has links)
Yes / The role of lichens as environmental monitors is widely recognised. Not only are they valuable as indicators of habitat stability and enyironmental continuity, but they are also effectiye in monitoring environmental quality. more particularly air and soil (and more recently water) pollution. In the past. the main role of lichens in this context has been to monitor sulphur dioxide air pollution. especially stable and rising levels (Seaward 1993). Howeyer, it has also been shown that lichens arc effective monitors of falling levels of gaseous sulphur dioxide and indeed of other pollutants. some of which are manifesting themselves as a consequence of the reduction in the former; of particular interest in this respect is the use of lichens to detect and determine the extent of qualitative changes in air pollution such as the impact of acid rain and hypertrophication (Seaward 1997: Seaward & Coppins 2(04).

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