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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.
41

Water quality trends in the Eerste River, Western Cape, 1990 - 2005.

Ngwenya, Faith January 2006 (has links)
<p>The Eerste River is a river system which has, over the years, been subjected to human interference. The purpose of this study was to investigatge temporal and spatial trends in the water quality of the Eerste River between 1990 and 2005. The study results revealed that the major trends in the water quality of the Eerste River are more spatial than temporal.</p>
42

Optimization of paths and locations of water quality monitoring systems in surface water environments

Nam, Kijin. January 2008 (has links)
Thesis (Ph.D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Aral, Mustafa; Committee Member: Guan, Jiabao; Committee Member: Kim, Seong-Hee; Committee Member: Roberts, Philip; Committee Member: Uzer, Turgay.
43

Proposta de metodologia para avaliação de redes de voz sobre IP / Proposal of Methodology for Evaluation of Voice over IP Networks

Silva, Vandersilvio da January 2006 (has links)
A redução de custo com telefonia através do uso de voz sobre IP tem disparado a busca de soluções que transformem redes IP originalmente dedicadas a transporte de dados em redes para transporte de voz. Esta dissertação tem por objetivo apresentar uma metodologia para sistematizar a avaliação de redes para o tráfego de voz sobre IP de acordo com as possibilidades disponíveis no cenário a ser avaliado. Inicialmente é dada uma visão geral de voz sobre IP, apresentando os protocolos utilizados, os fatores que influenciam na qualidade da voz e os métodos de avaliação de qualidade da voz. Na seqüência são apresentados trabalhos correlatos a avaliação de qualidade de aplicações de voz sobre IP. E por fim descreve-se a proposta de uma metodologia para sistematizar a avaliação de redes com VoIP. / The use of voice over IP telephony was started with solutions to adapt existent data networks to carrier voice streams. The use of monitoring techniques, QoS and signaling protocols can be combined on a such design. Our goal is to present a methodology to evaluate and choose the probing points and the voice quality evaluation techniques to be used in network redesign. An overview about VoIP protocols and parameters that change the voice quality are presented as well as some related works on evaluating voice quality based on network parameters. A proposed methodology is presented, with a case study to show how one can choose the right combination of probing points with some voice quality measurement technique.
44

Proposta de metodologia para avaliação de redes de voz sobre IP / Proposal of Methodology for Evaluation of Voice over IP Networks

Silva, Vandersilvio da January 2006 (has links)
A redução de custo com telefonia através do uso de voz sobre IP tem disparado a busca de soluções que transformem redes IP originalmente dedicadas a transporte de dados em redes para transporte de voz. Esta dissertação tem por objetivo apresentar uma metodologia para sistematizar a avaliação de redes para o tráfego de voz sobre IP de acordo com as possibilidades disponíveis no cenário a ser avaliado. Inicialmente é dada uma visão geral de voz sobre IP, apresentando os protocolos utilizados, os fatores que influenciam na qualidade da voz e os métodos de avaliação de qualidade da voz. Na seqüência são apresentados trabalhos correlatos a avaliação de qualidade de aplicações de voz sobre IP. E por fim descreve-se a proposta de uma metodologia para sistematizar a avaliação de redes com VoIP. / The use of voice over IP telephony was started with solutions to adapt existent data networks to carrier voice streams. The use of monitoring techniques, QoS and signaling protocols can be combined on a such design. Our goal is to present a methodology to evaluate and choose the probing points and the voice quality evaluation techniques to be used in network redesign. An overview about VoIP protocols and parameters that change the voice quality are presented as well as some related works on evaluating voice quality based on network parameters. A proposed methodology is presented, with a case study to show how one can choose the right combination of probing points with some voice quality measurement technique.
45

Synthesis of smart nanomaterials for preconcentration and detection of E.coli in water

Mahlangu, Thembisile Patience 06 1900 (has links)
It is common knowledge that water is one of the basic needs for human beings. However, the consumption of contaminated water can lead to waterborne diseases and fatalities. It is, therefore imperative to constantly monitor the quality of potable water. There are numerous technologies used for water quality monitoring. These technologies are relatively effective however these tests are expensive and complex to use, which then require experienced technicians to operate them. Other tests are not rapid, making consumers of water susceptible to waterborne diseases. In this study, dye-doped, surface functionalized silica nanoparticles (SiNPs) and surface-functionalized magnetic nanocomposites (MNCs) were proposed as materials that can be applied in order to reduce the time taken to get results as well as to make the processes less complex and portable. The aim of this study was to synthesize and characterize surface functionalized dye-doped SiNPs and surface functionalized MNCs for detection and preconcentration of in water. Additionally, proof of concept had to be shown using the synthesized materials. SiNPs were the materials of choice due to their easily functionalized surfaces and their strong optical properties. SiNPs are photostable and they do not leach in solution due to the inert nature of the silica matrix in aqueous media. MNCs were chosen as materials of choice for preconcentration of E. coli in water because they are easy to synthesize and they can be applied in various biological applications due to their functional groups. SiNPs were synthesized using the water-in-oil microemulsion. The SiNPs were further functionalized with amine and carboxyl groups and avidin. Thereafter, they were bioconjugated with biotinylated anti-E. coli antibodies. The pure and surface functionalized SiNPs were characterized using ATR-FTIR spectroscopy, FE-SEM, HR-TEM, Zeta Sizer, UV-vis spectroscopy and spectrofluorometry. The application of the dye—doped surface functionalized SiNPs in E. coli detection was characterized using the fluorescence plate reader. The SiNPs were spherical and uniform in size. They increased in size as they were being functionalized, ranging from 21.20 nm to 75.06 nm. The SiNPs were successfully functionalized with amine and carboxyl groups as well as with avidin and antibodies. Two methods were investigated for carboxyl group attachment (direct and indirect attachment) and the direct attachment method yielded the best results with a surface charge of -31.9 mV compared to -23.3 mV of the indirect method. The dye loading was found to be 1% after particle synthesis. The optical properties of the Ru(Bpy) dye were enhanced 3 fold when they were encapsulated in the Si matrix. The SiNPs were binding to the E. coli cells and enabled detection. MNCs were synthesized through in-situ polymerization. The MNCs were characterized using ATR-FTIR spectroscopy, SEM, TEM and XRD. The MNCs were successfully functionalized with carboxyl groups. The increase in size of the nanocomposites as seen in SEM images proved that the Fe3O4 was successfully encapsulated in the polymer matrix. The MNCs were proven to be magnetic by a simple magnetism test whereby they were separated in an aqueous solution using an external magnetic field. The antibody-labelled MNCs were binding to the E. coli cells as shown in TEM images. E. coli cells were removed from water at varying concentrations of 1x106 CFU/mL to 1x109 CFU/mL at 10 mL volumes. This study has demonstrated that dye-doped SiNPs amplify the signal of E. coli cells using fluorescence. The study has also demonstrated that the MNCs can be applied in sample preconcentration and enrichment for E. coli detection. However, further studies should investigate and optimize the combination of the two techniques in a point of use device for water quality testing of 100 mL-samples as per the requirement of the SANS 241 standard. / Civil and Chemical Engineering / M. Tech. (Chemical Engineering)
46

Proposta de metodologia para avaliação de redes de voz sobre IP / Proposal of Methodology for Evaluation of Voice over IP Networks

Silva, Vandersilvio da January 2006 (has links)
A redução de custo com telefonia através do uso de voz sobre IP tem disparado a busca de soluções que transformem redes IP originalmente dedicadas a transporte de dados em redes para transporte de voz. Esta dissertação tem por objetivo apresentar uma metodologia para sistematizar a avaliação de redes para o tráfego de voz sobre IP de acordo com as possibilidades disponíveis no cenário a ser avaliado. Inicialmente é dada uma visão geral de voz sobre IP, apresentando os protocolos utilizados, os fatores que influenciam na qualidade da voz e os métodos de avaliação de qualidade da voz. Na seqüência são apresentados trabalhos correlatos a avaliação de qualidade de aplicações de voz sobre IP. E por fim descreve-se a proposta de uma metodologia para sistematizar a avaliação de redes com VoIP. / The use of voice over IP telephony was started with solutions to adapt existent data networks to carrier voice streams. The use of monitoring techniques, QoS and signaling protocols can be combined on a such design. Our goal is to present a methodology to evaluate and choose the probing points and the voice quality evaluation techniques to be used in network redesign. An overview about VoIP protocols and parameters that change the voice quality are presented as well as some related works on evaluating voice quality based on network parameters. A proposed methodology is presented, with a case study to show how one can choose the right combination of probing points with some voice quality measurement technique.
47

Role of biological monitoring in water quality assessment and a case study on the Crocodile River, Eastern Transvaal

Roux, Dirk Johannes 14 May 2014 (has links)
M.Sc. (Zoology) / National water quality monitoring in South Africa has in the past mainly focused on measuring physical and chemical variables. However, it is increasingly realised that measuring physical and chemical variables on their own cannot provide an accurate account of the general "health" of an aquatic ecosystem. Biological communities, on the other hand, are accurate indicators of overall environmental conditions. Water quality management must, therefore, rely on comparative data for both chemical composition and biological effects. In fact, it appears as if biological monitoring (biomonitoring) is worldwide becoming a primary tool in assessing environmental condition and verifying compliance with effluent discharge. This study classified different biomonitoring approaches and techniques under bioassessment (referring to the field oriented biomonitoring protocols which make use of biotic indices to assess water quality); bioassays (toxicity tests which is usually laboratory-based); behavioural bioassays (including aspects such as early warning systems, and preference and avoidance studies); bacteriological studies (the monitoring of certain microbes to allow the detection of faecal contamination); measurement of bioaccumulation (referring to the methods by which the uptake and retention of chemicals in the body of an organism can be monitored); and fish pathology (fish health studies dealing with the causes, processes and effects of disease). Habitat assessment and evaluation was identified as an essential part of any biosurvey. There can be little uncertainty about the mutual dependence of habitat quality, biological health and chemical characteristics of water in the environment. Relative habitat condition, as the principal determinant of attainable biological potential, should set the context for interpreting the results of a biosurvey and can be used as a general predictor of biological condition. Chemistry can further help to explain and characterise certain impacts. The Crocodile River, Eastern Transvaal, was selected for conducting a case study. The SASS2 rapid bioassessment protocol, as well as a habitat quality index (Hal) was used during five consecutive biosurveys. From the results obtained in this study, it appears as if biomonitoring can be used to good effect in overall environmental assessment. The SASS2 index appeared to be both a robust and sensitive indicator of environmental condition. Application of the SASS2 technique on a regional or even national basis should be feasible with regard to simplicity and practicality. It is also cheaper and less labour intensive than comprehensive chemical monitoring. However, bioassessments should not replace but rather compliment chemical and physical monitoring.
48

Business Process Performance Measurement for Rollout Success / Prestandamätning i affärsprocesser för framgång i driftsättning

Axelsson, Mattias, Sonesson, Johan January 2004 (has links)
Business process improvement for increased product quality is of continuous importance in the software industry. Quality managers in this sector need effective, hands-on tools for decision-making in engineering projects and for rapidly spotting key improvement areas. Measurement programs are a widespread approach for introducing quality improvement in software processes, yet employing all-embracing state-of-the art quality assurance models is labor intensive. Unfortunately, these do not primarily focus on measures, revealing a need for an instant and straightforward technique for identifying and defining measures in projects without resources or need for entire measurement programs. This thesis explores and compares prevailing quality assurance models using measures, rendering the Measurement Discovery Process constructed from selected parts of the PSM and GQM techniques. The composed process is applied to an industrial project with the given prerequisites, providing a set of measures that are subsequently evaluated. In addition, the application gives foundation for analysis of the Measurement Discovery Process. The application and analysis of the process show its general applicability to projects with similar constraints as well as the importance of formal target processes and exhaustive project domain knowledge among measurement implementers. Even though the Measurement Discovery Process is subject to future refinement, it is clearly a step towards rapid delivery of tangible business performance indicators for process improvement. / Vikten av förbättringar i affärsprocesser i syfte att öka produktkvaliteten i mjukvaruindustrin ökar stadigt. Kvalitetsansvariga i industrin behöver effektiva och påtagliga verktyg för beslutsfattande i utvecklingsprojekt och för lokalisering av förbättringsområden. Mätningsprogram är en utbredd ansats för kvalitetsförbättring i mjukvaruprocesser men användning av heltäckande kvalitetsmodeller är resurskrävande. Dessa fokuserar inte primärt på mätpunkter vilket blottar behovet av en snabb och direkt teknik för identifiering och definiering av mätpunkter i projekt som saknar resurser eller behov av heltäckande mätningsprogram. Denna uppsats undersöker och jämför rådande kvalitetssäkringsmodeller med mätpunkter, vilket resulterar i Measurement Discovery Process utifrån valda delar av PSM- och GQM-modellerna. Processen appliceras på ett industriellt projekt med nämnda förutsättningar, vilket skapar en uppsättning mätpunkter som sedan utvärderas. Detta ligger även till grund för utvärdering av Measurement Discovery Process. Appliceringen och utvärderingen av processen synliggör dess generella applicerbarhet på projekt med liknande begränsningar såväl som vikten av formella processer i målprojektet och omfattande domänkunskap hos de som implementerar mätningarna. Measurement Discovery Process är föremål för framtida förbättringar men samtidigt ett tydligt steg mot snabbt framtagande av konkreta prestandamått för kvalitetsförbättring i affärsprocesser. / Mattias Axelsson: +46 708 67 53 81 Johan Sonesson: +46 709 72 74 30 / +46 40 12 48 03
49

Kvalita služeb v hotelnictví - spokojenost zákazníka / Service Quality in Hotel Industry - Customer Satisfaction

Fučíková, Martina January 2009 (has links)
The theoretical part of the master thesis focuses mainly on particular methods to help to identify customer satisfaction with regard to the specific processes in the hotel industry. The practical part determines the customer satisfaction in the hotel Jalta. A customer satisfaction survey based on a research of the web pages www.hrs.com, www.booking.com, www.tripadvisor and the evaluation of questionnaires provided by the hotel Jalta has been carried out. In addition a mystery shopping with an enclosed report and suggestions for improvement were made. The goal was to examine the appropriateness of questions with regard to the output of information.
50

Investigating the relevance of quality measurement indicators for South African higher education libraries

Ntshuntshe-Matshaya, Pateka Patricia January 2021 (has links)
Philosophiae Doctor - PhD / This study investigates the relevance of quality measurement indicators at higher education libraries for faculty academics, librarians, and students. The study followed a mixed-method design with a mixture of quantitative and qualitative data collection. Faculty academics, librarians and students ranked the existing quality measurement indicators for South African higher education libraries. The findings revealed that for library quality measures to meet the needs of faculty academics, librarians, and students, the resources must be accessible both physically and virtually, and staff should be accountable and willing to offer services responsive to the users' needs and expectations of a safe, secure, and comfortable library space, be it physical or virtual. The qualitative data highlighted the importance of adequate resources and the adoption of new developments as measures for quality. Quality measurement indicators must include elements such as adequate funding; relevant resources aligned with teaching and learning programmes; programmes that are integrated into teaching plans; effective supplier collaboration with respect to the process of acquiring relevant learning materials; effective student training; communication of the value of library services and alignment with the student learning outcomes; research support in a digital environment with e-tools and website navigability; research data management; and open access, which is a prominent role of the library. Based on the data, there was a quality measure (process) that was commendable even though it did not form part of the existing quality measures nor a service whose relevance was assessed. The separation of undergraduate and postgraduate learning spaces was amongst those services that ranked quite high from the students' responses (qualitative data). Even though there were differences emphasized on each indicator by either faculty academics or students, there were also discrepancies in the interpretation of what each quality indicator means to each study population group. As the study of this nature has recommendations and gaps identified in terms of research findings, it is quite important to record that there was a series of gaps that were identified in terms of library expectations and perceptions. These gaps were suggested as part of further research that must be conducted to fill the void in terms of library users’ voices in the development of higher education library measurement indicators.

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