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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.
401

A comparative study of entrepreneurship education and entrepreneurial intentions amongst students at selected South African institutions of higher education

Matsheke, Moses Jametane 01 1900 (has links)
PhD. (Department of Business Administration, Faculty of Management Sciences), Vaal University of Technology. / Entrepreneurial intention (EI) is considered as an element used by researchers to measure the propensity of individuals to become entrepreneurs. Higher education institutions (HEIs) have been utilised globally by governments as mechanisms to increase the EIs of students by establishing entrepreneurship as an academic discipline and instituting entrepreneurship programmes at all educational levels. However, in South Africa, the Global Entrepreneurship Monitor (GEM) reports a decline in EIs in the last decade of the population aged 18-64 years. The current study investigated the influence of the entrepreneurship education (EE) at one selected Technical and Vocational Education and Training (TVET) college and a University of Technology (UOT) located in the Gauteng Province, South Africa through a comparative analysis. The Theory of Planned Behaviour (TPB) and the Theory of Reasoned Action (TRA) were used as theories to underpin the study. In addition, Self-efficacy (SE), Need to Achieve (NA) and Instrumental Readiness (IR) were included as constructs to examine further variables for EIs. The study adopted a survey design and followed a quantitative research approach in determining the relationship between the identified variables. A self-administered survey questionnaire was used to gather the data from the sampled students at the selected HEIs. The total number of usable questionnaires was 390 from the TVET college and 362 from the UOT, giving a total of 752 responses. The empirical analysis was performed by means of the descriptive statistics, exploratory factor analysis (EFA), Pearson correlations, and regression analysis. The descriptive analysis procedure was utilised to examine the demographic profile of the respondents as well as the perceptions of the respondents towards the research constructs of the study. The EFA procedure confirmed that all measurement scales applied in the study were unidimensional. The Pearson correlation analysis was used to examine the linear association between the constructs while the regression analysis was used to test the hypotheses. The results of the hypotheses tests revealed that EE was statistically significant in predicting the EI of the students from both the TVET college and UOT. The tests further revealed that EE was also statistically significant in predicting the Attitude towards Behaviour (ATB), Subjective Norm (SN), Perceived Behavioural Control (PBC), SE, NA and IR of the students from both HEIs in a similar manner. However, PBC, SE, and NA were found to be statistically insignificant for the TVET college students while for the UOT students only SN, NA and IR were statistically insignificant. The study concludes that EE is an important tool that can be used to enhance the EI of the students at both types of HEIs. It further draws the conclusion that students from the TVET college are more dependent on external factors such as the support of their families and friends as well as the availability of resources to start thinking of starting their own business, whereas those from the UOT are more reliant on internal motivation. Based on the results, the study recommends that subjects in the curriculum in HEIs should have a learning unit dedicated to stimulating entrepreneurship amongst students. Such an approach might inspire students to venture into entrepreneurship.
402

Utvärdering av luftrenare som använder sig av centrifugalteknologi : På uppdrag av Airission i samarbete med Karolinska Universitetssjukhuset i Huddinge / Assessment of the Efficiency of an Air Purification System Utilizing Centrifugal Technology : On Behalf of Airission, and in Collaboration with Karolinska University Hospital in Huddinge

Barsoumi, Rabi, Odowa, Mohammed January 2023 (has links)
Denna rapport presenterar en utvärdering av en centrifugal luftrenare från företaget Airission som användes i en infektionsavdelning på Karolinska Universitetssjukhuset. Airissions luftrenare rensar bort partiklar och aerosoler, genom så kallad centrifugalteknologi, en relativt oprövad teknologi för luftrening. Målet var att undersöka och försöka verifiera luftrenarens funktion och prestanda samt jämföra den med en konventionell luftrenare som använder traditionella tvåstegsfilter för att rena luft.För att utföra studien användes ett bioaerosolmätinstrument som i realtid mäter partikelnivåerna i rummet. Testerna utfördes under olika driftförhållanden och tidsintervall med luftrenare påslagen respektive avstängd. Datainsamlingen och analysen inkluderade beräkningen av medelvärdet, jämförelse av partikelnivåerna mellan de olika testfallen och beräkning av standardavvikelsen.Resultaten visade att Airissions centrifugala luftrenare fungerar väl för rening av luft från partiklar och aerosoler. Reningseffektiviteten var jämförbar med en konventionell luftrenare. Den var mer effektiv än en konventionell luftrenare utan användning av högeffektiva luftfilter, mer allmänt känt som HEPA-filter. En signifikant minskning av antalet partiklar i luften observerades medan luftrenaren var i drift. Det uppstod dock en del komplikationer vid appliceringen av HEPA-filtret, vilka kunde ha haft en negativ påverkan på båda luftrenarna. Sammanfattningsvis visar analysen att den tillämpade centrifugalteknologin hos Airissions luftrenare fungerar väl. Jämförelsen av den konventionella luftrenaren visar vissa fördelar med en luftrenare som använder centrifugal teknologi - både gällande effektivitet och kvalitet.Denna rapport bidrar till kunskapen om luftreningslösningar för att förbättra luftkvaliteten och minska spridningen av luftburna sjukdomar, framför allt i sjukhusmiljöer. Resultaten kan vara till nytta för fortsatt forskning och utveckling av mer effektiva luftrenare som i sin tur ger ett bättre skydd för patienter och sjukhuspersonal som exponeras för luftburna smittämnen. / This report presents an evaluation of a centrifugal air purifier from the company Airission used in an infectious ward at Karolinska University Hospital. Airission's air purifier removes particles and aerosols using centrifugal technology, a relatively untested technology for air purification. The goal was to investigate and attempt to verify the functionality and performance of the air purifier and compare it to a conventional air purifier that uses traditional two-stage filters for air purification.To conduct the study, a bioaerosol measuring instrument was used to measure real-time particle levels in the room. The tests were performed under different operating conditions and time intervals with the air purifier turned on and off. Data collection and analysis included calculating the mean values, comparing the particle levels between different test cases, and calculating the standard deviation.The results showed that Airission's centrifugal air purifier effectively purifies air from particles and aerosols. The purification efficiency was comparable to a conventional air purifier. It was more effective than a conventional air purifier without the use of highefficiency air filters, commonly known as HEPA filters. A significant reduction in the number of particles in the air was observed while the air purifier was in operation. However, some complications arose during the application of the HEPA filter, which could have had a negative impact on both air purifiers.In summary, the analysis demonstrates that the applied centrifugal technology in Airission's air purifier works well. The comparison with the conventional air purifier shows certain advantages of an air purifier that uses centrifugal technology - in terms of both efficiency and quality.This report contributes to the knowledge of air purification solutions to improve air quality and reduce the spread of airborne diseases, especially in hospital environments. The results can be useful for further research and development of more effective air purifiers, which in turn provide better protection for patients and hospital staff exposed to airborne pathogens.
403

Multivariate Vorhersagbarkeit von ICD-Schocks und Mortalität bei Patienten nach einer ICD-Neuimplantation / Risikostratifikation für maligne ventrikuläre Rhythmusstörungen / Multivariate predictability of ICD shocks and mortality in patients after an ICD new implant / Risk assessment for malignant ventricular rhythm disturbances

Lercher, Hendrik 22 November 2016 (has links)
No description available.
404

Measurements of Water-soluble Composition of Fine Atmospheric Particulate Matter (PM2.5) and Associated Precursor Gases via Ambient Ion Monitor-ion Chromatography (AIM-IC)

Markovic, Milos 30 August 2012 (has links)
Atmospheric fine particulate matter (PM2.5), which is mostly formed in the atmosphere from precursor gases, contributes to numerous environmental and health concerns. Quantifying the ambient concentrations of PM2.5 and precursor gases can be challenging. Hence, many scientific questions about the formation, chemical composition, and gas/particle partitioning of PM2.5 remain unanswered. Ambient Ion Monitor - Ion Chromatography (AIM-IC) was characterized and utilized to measure the water-soluble composition of PM2.5 (dominated by pNH4+, pSO42-, and pNO3-) and associated precursor gases (dominated by NH3(g), SO2(g), and HNO3(g)) during two field campaigns. The AIM-IC detection limits for hourly sampling were determined to be 3 - 45 ng m-3. The response time for “sticky” gases was significantly improved with a nylon denuder membrane. A novel inlet configuration for the AIM-IC, which minimizes sampling inlet losses and carryover in sample analyses, was implemented. Measurements from the BAQS-Met 2007 campaign were utilized to assess the accuracy of the AURAMS model and investigate gas/particle partitioning in SW Ontario. Due to high sulphate levels, NH3(g) was the limiting chemical factor in the formation and gas/particle partitioning of PM2.5. The errors in the predictions of relative humidity and free ammonia were responsible for the poor agreement iii between modelled and measured pNO3- values. The AIM-IC measurements from the CalNex 2010 study were compared to the CMAQ model and utilized to investigate the gas/particle partitioning in Bakersfield, CA. Very high NH3(g) concentrations were observed, and the formation and partitioning of PM2.5 was limited by HNO3(g) and H2SO4. Evidence of rapid removal of HNO3(g) by interactions with super-micron dust particles, and possibly with the alkaline surface was found. CMAQ exhibited significant biases in the predicted concentrations of pSO42-, NH3(g) and HNO3(g).
405

Measurements of Water-soluble Composition of Fine Atmospheric Particulate Matter (PM2.5) and Associated Precursor Gases via Ambient Ion Monitor-ion Chromatography (AIM-IC)

Markovic, Milos 30 August 2012 (has links)
Atmospheric fine particulate matter (PM2.5), which is mostly formed in the atmosphere from precursor gases, contributes to numerous environmental and health concerns. Quantifying the ambient concentrations of PM2.5 and precursor gases can be challenging. Hence, many scientific questions about the formation, chemical composition, and gas/particle partitioning of PM2.5 remain unanswered. Ambient Ion Monitor - Ion Chromatography (AIM-IC) was characterized and utilized to measure the water-soluble composition of PM2.5 (dominated by pNH4+, pSO42-, and pNO3-) and associated precursor gases (dominated by NH3(g), SO2(g), and HNO3(g)) during two field campaigns. The AIM-IC detection limits for hourly sampling were determined to be 3 - 45 ng m-3. The response time for “sticky” gases was significantly improved with a nylon denuder membrane. A novel inlet configuration for the AIM-IC, which minimizes sampling inlet losses and carryover in sample analyses, was implemented. Measurements from the BAQS-Met 2007 campaign were utilized to assess the accuracy of the AURAMS model and investigate gas/particle partitioning in SW Ontario. Due to high sulphate levels, NH3(g) was the limiting chemical factor in the formation and gas/particle partitioning of PM2.5. The errors in the predictions of relative humidity and free ammonia were responsible for the poor agreement iii between modelled and measured pNO3- values. The AIM-IC measurements from the CalNex 2010 study were compared to the CMAQ model and utilized to investigate the gas/particle partitioning in Bakersfield, CA. Very high NH3(g) concentrations were observed, and the formation and partitioning of PM2.5 was limited by HNO3(g) and H2SO4. Evidence of rapid removal of HNO3(g) by interactions with super-micron dust particles, and possibly with the alkaline surface was found. CMAQ exhibited significant biases in the predicted concentrations of pSO42-, NH3(g) and HNO3(g).
406

OpenBSD Hardware Sensors — Environmental Monitoring and Fan Control

Murenin, Constantine Aleksandrovich 18 May 2010 (has links)
This thesis discusses the motivation, origin, history, design guidelines, API, the device drivers and userland utilities of the hardware sensors framework available in OpenBSD. The framework spans multiple utilities in the base system and the ports tree, is utilised by over 75 drivers, and is considered to be a distinctive and ready-to-use feature that sets OpenBSD apart from many other operating systems, and in its root is inseparable from the OpenBSD experience. The present framework, however, is missing the functionality that would allow the user to interface with the fan-controlling part of the hardware monitors. We therefore discuss the topic of fan control and introduce sysctl-based interfacing with the fan-controlling capabilities of microprocessor system hardware monitors. The discussed prototype implementation reduces the noise and power-consumption characteristics in fans of personal computers, especially of those PCs that are designed from off-the-shelf components. We further argue that our prototype is easier, more intuitive and robust compared to solutions available elsewhere.
407

治療溶電子線のエネルギ-および生体等価物質中吸収線量分布直読装置の研究開発

青山, 隆彦, 前越, 久, 津坂, 昌利, 小山, 修司 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(C)(2) 課題番号:07680528 研究代表者:青山 隆彦 研究期間:1995-1996年度
408

OpenBSD Hardware Sensors — Environmental Monitoring and Fan Control

Murenin, Constantine Aleksandrovich 18 May 2010 (has links)
This thesis discusses the motivation, origin, history, design guidelines, API, the device drivers and userland utilities of the hardware sensors framework available in OpenBSD. The framework spans multiple utilities in the base system and the ports tree, is utilised by over 75 drivers, and is considered to be a distinctive and ready-to-use feature that sets OpenBSD apart from many other operating systems, and in its root is inseparable from the OpenBSD experience. The present framework, however, is missing the functionality that would allow the user to interface with the fan-controlling part of the hardware monitors. We therefore discuss the topic of fan control and introduce sysctl-based interfacing with the fan-controlling capabilities of microprocessor system hardware monitors. The discussed prototype implementation reduces the noise and power-consumption characteristics in fans of personal computers, especially of those PCs that are designed from off-the-shelf components. We further argue that our prototype is easier, more intuitive and robust compared to solutions available elsewhere.
409

An improved maintenance management strategy for gas field equipment in Escravos gas–to–liquid plant, Nigeria / T.E. Onyenanu

Onyenanu, Tochukwu Emmanuel January 2010 (has links)
The safety record of most petrochemical industries in the world and Nigeria in particle, has not been able to come down to the maximum allowable range of 0 - 0.1 percent of tolerance on recordable injuries, due to increasing failure rates of equipment within the plant. Investigations on the maintenance audit carried out on the Nigerian Gas Company (NGC) revealed that 85 percent of such failures are directly linked to improper adaptability of an effective maintenance management strategy and plan within the petrochemical industries in Nigeria. Equally, the growth and continuous operation of any plant depends to a large extent on the maintenance of the equipment that refines the Crude Oil and natural Gas. As such, various maintenance management systems have been used over the years for the actualisation of the above purpose but with minimal success. This is evident in the fact that the level of maintenance performance of most Nigerian Petroleum Companies is always on the corrective maintenance model, which indirectly implies that the plant normally breaks down before maintenance management is applied. A critical look at the deficiency of improper adaptability of these maintenance management plans have conspicuously manifested in five major categories of maintenance failures which includes the following; * Failure of safety critical equipment due to lack of maintenance * Human error during maintenance * Static or spark discharge during maintenance in an intrinsically unsafe zone * Incompetence of maintenance staff, and * Poor communication between maintenance and production staff. These gaps as identified in this research must be corrected in the Nigerian Gas Industry if meaningful progress is to be made. Gas – To – Liquid technology is a very complex technology and with natural gas as the basic raw material, the technology not only looks intimidating but also is full of potential hazards. People are naturally afraid of the complex nature of gas in a confined environment (because of its highly combustible nature), its gaseous state makes it more complex for it to be kept under control and at the same time be moved from one form to another at different temperatures and pressures. The maintenance audit carried out on the Nigerian Gas Company (NGC) revealed some major loopholes in the maintenance management strategies adopted in the country. The audit reveals that the degree of adherence to conditions attached towards the maintenance management strategy of this equipment (in this case Gas field equipment) was too poor. Based on the above, this research is meant to improve the existing maintenance management strategy, by developing a Maintenance Management Strategy (MMS) that will be suitable for gas field equipment in the Escravos Gas–To– Liquid (EGTL) plant, planned to be commissioned in Nigeria early 2011. The need to research the above mentioned Maintenance Strategy became imperative due to the fact that the rate at which most of the petrochemical plants in the world are being gutted by fire, mainly due to poor maintenance management systems is alarming. This research work proffered solutions that will reduce or completely eliminate the highlighted problems above. This was based on investigations and analysis carried out in the chosen research area. Models were developed for the actualization of this Improved Maintenance Management Strategy (IMMS), so that the desired safe operability of the gas field equipment in the Escravos Gas–To– Liquid (EGTL) plant will be achieved without maintenance failure of any kind. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2011.
410

An improved maintenance management strategy for gas field equipment in Escravos gas–to–liquid plant, Nigeria / T.E. Onyenanu

Onyenanu, Tochukwu Emmanuel January 2010 (has links)
The safety record of most petrochemical industries in the world and Nigeria in particle, has not been able to come down to the maximum allowable range of 0 - 0.1 percent of tolerance on recordable injuries, due to increasing failure rates of equipment within the plant. Investigations on the maintenance audit carried out on the Nigerian Gas Company (NGC) revealed that 85 percent of such failures are directly linked to improper adaptability of an effective maintenance management strategy and plan within the petrochemical industries in Nigeria. Equally, the growth and continuous operation of any plant depends to a large extent on the maintenance of the equipment that refines the Crude Oil and natural Gas. As such, various maintenance management systems have been used over the years for the actualisation of the above purpose but with minimal success. This is evident in the fact that the level of maintenance performance of most Nigerian Petroleum Companies is always on the corrective maintenance model, which indirectly implies that the plant normally breaks down before maintenance management is applied. A critical look at the deficiency of improper adaptability of these maintenance management plans have conspicuously manifested in five major categories of maintenance failures which includes the following; * Failure of safety critical equipment due to lack of maintenance * Human error during maintenance * Static or spark discharge during maintenance in an intrinsically unsafe zone * Incompetence of maintenance staff, and * Poor communication between maintenance and production staff. These gaps as identified in this research must be corrected in the Nigerian Gas Industry if meaningful progress is to be made. Gas – To – Liquid technology is a very complex technology and with natural gas as the basic raw material, the technology not only looks intimidating but also is full of potential hazards. People are naturally afraid of the complex nature of gas in a confined environment (because of its highly combustible nature), its gaseous state makes it more complex for it to be kept under control and at the same time be moved from one form to another at different temperatures and pressures. The maintenance audit carried out on the Nigerian Gas Company (NGC) revealed some major loopholes in the maintenance management strategies adopted in the country. The audit reveals that the degree of adherence to conditions attached towards the maintenance management strategy of this equipment (in this case Gas field equipment) was too poor. Based on the above, this research is meant to improve the existing maintenance management strategy, by developing a Maintenance Management Strategy (MMS) that will be suitable for gas field equipment in the Escravos Gas–To– Liquid (EGTL) plant, planned to be commissioned in Nigeria early 2011. The need to research the above mentioned Maintenance Strategy became imperative due to the fact that the rate at which most of the petrochemical plants in the world are being gutted by fire, mainly due to poor maintenance management systems is alarming. This research work proffered solutions that will reduce or completely eliminate the highlighted problems above. This was based on investigations and analysis carried out in the chosen research area. Models were developed for the actualization of this Improved Maintenance Management Strategy (IMMS), so that the desired safe operability of the gas field equipment in the Escravos Gas–To– Liquid (EGTL) plant will be achieved without maintenance failure of any kind. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2011.

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