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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.
71

Study of macroscopic and microscopic homogeneity of DEPFET X-ray detectors / Untersuchung der makroskopischen und mikroskopischen Homogenität von DEPFET-Röntgendetektoren

Bergbauer, Bettina 15 January 2016 (has links) (PDF)
For the X-ray astronomy project Advanced Telescope for High ENergy Astrophysics (Athena) wafer-scale DEpleted P-channel Field Effect Transistor (DEPFET) detectors are proposed as Focal Plane Array (FPA) for the Wide Field Imager (WFI). Prototype structures with different pixel layouts, each consisting of 64 x 64 pixels, were fabricated to study four different DEPFET designs. This thesis reports on the results of the electrical and spectroscopic characterization of the different DEPFET designs. With the electrical qualification measurements the transistor properties of the DEPFET structures are investigated in order to determine whether the design intentions are reflected in the transistor characteristics. In addition, yield and homogeneity of the prototypes can be studied on die, wafer and batch level for further improvement of the production technology with regard to wafer-scale devices. These electrical characterization measurements prove to be a reliable tool to preselect the best detector dies for further integration into full detector systems. The spectroscopic measurements test the dynamic behavior of the designs as well as their spectroscopic performance. In addition, it is revealed how the transistor behavior translates into the detector performance. This thesis, as the first systematic study of different DEPFET designs on die and detector level, shows the limitations of the current DEPFET assessment methods. Thus, it suggests a new concise characterization procedure for DEPFET detectors as well as guidelines for expanded testing in order to increase the general knowledge of the DEPFET. With this study of four different DEPFET variants not only designs suitable for Athena mission have been found but also improvement impulses for the starting wafer-scale device production are provided.
72

Entrepreneurial intentions and start-up realities : the case of industrial design students in South Africa

Mvula, Althea Elizabeth 06 1900 (has links)
Industrial design is recognised for the value-oriented benefits it offers to businesses. Industrial design ensures that new products are more efficient, usable, convenient and safe to use within the evolving business environment. One of the important factors for the continuous achievement of high product quality and general economic growth and stability in countries such as West Germany, Korea and Japan is their sound industrial design base. Industrial design programmes can be instrumental to ignite an entrepreneurial and innovation spirit to assist in curbing the high unemployment rate and very low levels of entrepreneurial intentions in South Africa. The core of tertiary industrial design students has unique capabilities that can assist the South African economy to stimulate manufacturing, job creation and economic growth. The purpose of this study was to investigate the entrepreneurial intentions among industrial design students enrolled for the programme in Three-Dimensional Design, at Universities of Technology in South Africa. In addition, this study investigates the relationship between entrepreneurial intentions and actual business formation by graduates of the programme. Studies have been carried out in South Africa on entrepreneurial intentions, but not on the formation, occurrence and implementation of entrepreneurial intentions amongst industrial design students, specifically. To test the links between business education and entrepreneurial intentions, a research model based on Ajzen’s (1985) Theory of Planned Behaviour was adopted and tested using quantitative empirical data collected from students in industrial design at two Universities of Technology. Quantitative data were collected from a sample of 161 participants using a validated self-administered questionnaire. IBM SPSS and STATA were used to conduct descriptive statistics, Chi-square tests, factor analysis, reliability and structural equation modelling on the primary quantitative data. The empirical evidence partially supports the effectiveness of the Theory of Planned Behaviour in predicting entrepreneurial intentions. Although perceived social norms and self-efficacy is positively related to entrepreneurial intentions, results failed to reach statistical significance. However, personal attitude was found to mediate the relationship between these variables and entrepreneurial intention. Whilst business education is positively related to self-efficacy, entrepreneurial knowledge is positively related to higher levels of personal attitude and self-efficacy. The transformation of entrepreneurial intentions into actual business start-ups were investigated using qualitative empirical data collected from past graduates of the Three-Dimensional Design programme. Qualitative data were collected from a sample of 22 graduates through structured interviews. ATLAS.ti version 7.5.9 was used to analyse the qualitative data. The researcher provided evidence that there is a relationship between entrepreneurial intentions and the actual start-up of a business, as 45.5 per cent of graduates started businesses. Furthermore, business education positively influenced the actual start-up of businesses. However, graduates experienced many challenges to business start-up, with implications for the teaching of business subjects and for policy makers. / Business Management / D. Com. (Business Management)
73

Návrhová studie letiště VFR / Design Study of VFR Airport

Brandejský, Petr January 2010 (has links)
The final master´s thesis targets to create concept study of VFR airport.This airport should be build up in southeast part of Czech republic, in the vicinity of the town Valašské Klobouky. In this work there are explained essential terms and definitions refered to basic rules and law. There are explained also civil aviation law and requirements of L14 regulations. Aeroclub is submitter of this work. It establishes basic conditions for airport area searching. The length of the runway is influenced mainly by performance of used aircrafts. It was impossible to find any acceptable field in searched area. There is a posibility how to solve this problem. There can be build up a runway for take-off and landings of small aeroplanes. In the second part of this thesis there are defined basic requirements on these fields. These requirements are applicated on chosen field. At the end of this thesis there is propounded an option how to dislocate runway, taxiways, aprons, hangars and other buildings.
74

Study of macroscopic and microscopic homogeneity of DEPFET X-ray detectors

Bergbauer, Bettina 17 December 2015 (has links)
For the X-ray astronomy project Advanced Telescope for High ENergy Astrophysics (Athena) wafer-scale DEpleted P-channel Field Effect Transistor (DEPFET) detectors are proposed as Focal Plane Array (FPA) for the Wide Field Imager (WFI). Prototype structures with different pixel layouts, each consisting of 64 x 64 pixels, were fabricated to study four different DEPFET designs. This thesis reports on the results of the electrical and spectroscopic characterization of the different DEPFET designs. With the electrical qualification measurements the transistor properties of the DEPFET structures are investigated in order to determine whether the design intentions are reflected in the transistor characteristics. In addition, yield and homogeneity of the prototypes can be studied on die, wafer and batch level for further improvement of the production technology with regard to wafer-scale devices. These electrical characterization measurements prove to be a reliable tool to preselect the best detector dies for further integration into full detector systems. The spectroscopic measurements test the dynamic behavior of the designs as well as their spectroscopic performance. In addition, it is revealed how the transistor behavior translates into the detector performance. This thesis, as the first systematic study of different DEPFET designs on die and detector level, shows the limitations of the current DEPFET assessment methods. Thus, it suggests a new concise characterization procedure for DEPFET detectors as well as guidelines for expanded testing in order to increase the general knowledge of the DEPFET. With this study of four different DEPFET variants not only designs suitable for Athena mission have been found but also improvement impulses for the starting wafer-scale device production are provided.
75

'Framing and classifying' the implementation of the grade 10 curriculum and assessment policy statement : a case study of selected schools in KwaZulu-Natal / 'Framing and classifying' the implementation of the grade ten curriculum and assessment policy statement

Chamane, Thabile Carol January 2015 (has links)
The South African education system has been evolving since the country became democratic in 1994 and a number of curriculum reforms have been introduced within a short space of time. These reforms revolve around power and control and therefore, Bernstein’s concepts of classification and framing form the conceptual framework for this study. This study attempts to give a picture of what is currently happening in schools pertaining to the implementation of the grade 10 Life Sciences (LS), Business Studies (BS), and Engineering Graphics and Design (EGD) Curriculum and Assessment Policy Statement (CAPS). The dual aim of this study was to find out educators’ understanding and interpretation of the CAPS that can be observed in their teaching practice and to establish how decisions on subject content (selection, sequencing and pacing) are made. Also of importance was to determine whether educators view and treat their subject as unique or as similar to other subjects. The study used a qualitative approach, using case study design. Observations were used as the main method for data construction. Four LS, BS and EGD educators from four different schools were observed teaching the same class for five consecutive lessons. Thereafter, these educators were interviewed. For triangulation purposes, learners and the subject advisor were participants in this thesis. For this purpose a group of ten randomly selected learners from observed classes per subject and school were requested to complete a questionnaire and the LS, BS and EGD subject advisors were interviewed. The subject advisors insisted that educators follow the CAPS so that learners would be able to write common assessment tasks at the end of each term. Although educators claimed that they were following the CAPS regarding content selection, sequencing and pacing, observations showed that educators were not following the CAPS document. The findings suggest that well coordinated interventions are required to support and monitor educators’ practice. / Curriculum and Instructional Studies / D. Ed. (Curriculum Studies)
76

Systematic Analysis and Comparison of Stress Minimizing Notch Shapes : Obtaining a stress concentration factor of Kt=1 without FEM-Code

Ciomber, Isabelle, Jakel, Roland 08 May 2014 (has links) (PDF)
Als Stand der Technik sind einfache, kreisförmige Verrundungen zur Reduktion von Kerbspannungen an Querschnittsübergängen bekannt, für die aus Tabellenwerken / Diagrammen in der Literatur die Formzahl einfach abgelesen werden kann. Die Effizienz der Spannungsreduktion solcher Lösungen ist jedoch sehr begrenzt. Ziel der Arbeit ist es daher, dem Konstrukteur bzw. Berechnungsingenieur ein Verfahren in die Hand zu geben, mit dem er für Standardquerschnittsübergänge und Standardlastfälle "Nicht-Kreiskerben" ohne teure und zeitaufwendige FEM-Analyse einfach durch Nutzung geeigneter Formzahldiagramme auslegen kann. Dabei sind sogar Formzahlen von nahezu eins möglich, d.h., in der "Kerbe" bleibt praktisch nur noch die Nennspannung übrig. Die Präsentation ist zweitgeteilt: Im ersten Teil werden die Arbeitsmethoden bzw. Softwarefunktionen und verwendeten Softwarewerkzeuge vorgestellt: Dies sind die Programme Creo Parametric als vollparametrisches CAD-Werkzeug und Creo Simulate als p-FEM-Programm der Parametric Technology Coprporation (PTC). Der zweite Teil der Präsentation beschreibt den Gültigkeitsbereich sowie die untersuchten Kerbgeometrien: Die einfache kreisförmige Verrundung als Stand der Technik, die Zwei-Radien-Kerbe, die Baud-Kurve, die Methode der Zugdreiecke nach Claus Mattheck, die elliptische Kerbe sowie die konische Rundung als generalisierte elliptische Kerbe. Es wird kurz eine Bibliothek vorgestellt, mit der solche Kerben einfach ausgelegt werden können, d.h. Ihre exakte Geometrie festgelegt sowie die zugehörige Formzahl αk bestimmt werden kann. / Circular (one-radius) fillets are known as state-of-the-art for reducing notch stresses at cross section transitions. The stress concentration factor Kt of such geometries can be read out from diagrams/tables given in the literature. However, the efficiency of stress reduction of circular notches is very limited. The goal of the work therefor is to present a method for the designer/analyst how to design non-circular notches/fillets just by using suitable Kt-diagrams without time-consuming and expensive FEM analyses. Kt-numbers of nearly one are possible, that means in the "notch" just the nominal stress appears and no stress concentration takes place. The presentation has two parts: Part one describes the working methods and software functions as well as software tools: Creo Parametric as fully-parametric CAD program and Creo Simulate as embedded p-FEM-tool from Parametric Technology Corporation (PTC) have been used. The second part describes the range of validity and the examined notch geometries: The one-radius fillet as state-of-the-art, the two-radii filet, the Baud-curve, the method of tensile triangles from Claus Mattheck, the standard elliptical fillet and the conical round as generalized elliptical fillet. A notch layout library is shortly presented that allows to design such fillets, that means exactly determine the notch geometry and the related stress concentration factor Kt.
77

'Framing and classifying' the implementation of the grade 10 curriculum and assessment policy statement : a case study of selected schools in KwaZulu-Natal / 'Framing and classifying' the implementation of the grade ten curriculum and assessment policy statement

Chamane, Thabile Carol January 2015 (has links)
The South African education system has been evolving since the country became democratic in 1994 and a number of curriculum reforms have been introduced within a short space of time. These reforms revolve around power and control and therefore, Bernstein’s concepts of classification and framing form the conceptual framework for this study. This study attempts to give a picture of what is currently happening in schools pertaining to the implementation of the grade 10 Life Sciences (LS), Business Studies (BS), and Engineering Graphics and Design (EGD) Curriculum and Assessment Policy Statement (CAPS). The dual aim of this study was to find out educators’ understanding and interpretation of the CAPS that can be observed in their teaching practice and to establish how decisions on subject content (selection, sequencing and pacing) are made. Also of importance was to determine whether educators view and treat their subject as unique or as similar to other subjects. The study used a qualitative approach, using case study design. Observations were used as the main method for data construction. Four LS, BS and EGD educators from four different schools were observed teaching the same class for five consecutive lessons. Thereafter, these educators were interviewed. For triangulation purposes, learners and the subject advisor were participants in this thesis. For this purpose a group of ten randomly selected learners from observed classes per subject and school were requested to complete a questionnaire and the LS, BS and EGD subject advisors were interviewed. The subject advisors insisted that educators follow the CAPS so that learners would be able to write common assessment tasks at the end of each term. Although educators claimed that they were following the CAPS regarding content selection, sequencing and pacing, observations showed that educators were not following the CAPS document. The findings suggest that well coordinated interventions are required to support and monitor educators’ practice. / Curriculum and Instructional Studies / D. Ed. (Curriculum Studies)
78

The integration of indigenous graphics knowledge and skills to enhance Grade 9 learners’ understanding of graphic designs in Technology Education

Blose, Princess 05 August 2020 (has links)
Abstract in English, Swati and Ndebele / This single descriptive case study explored the integration of indigenous graphics knowledge and skills into the Technology curriculum of a school in the Ehlanzeni District of the Mpumalanga Province with a Grade 9 Technology teacher and the learners. The integration of indigenous knowledge and skills can help promote Grade 9 learners’ understanding of graphic design, which forms part of the content taught in Technology Education. The graphics knowledge and skills existent in the indigenous contexts from which most of learners come can make the learning of graphic design relevant and more understandable to learners. Hence, there was a need to research this issue. One Grade 9 Technology teacher was purposively selected for an interview and observed while teaching the class. Seven learners from this teacher’s class were also selected to be interviewed. The data analysed in the present study were obtained from the teacher and seven learners. The constructivist theory of learning framed this study. The findings revealed that, although the teacher had some understanding of technology, (i) she battled with the concept of indigenous knowledge; (ii) she was unaware that indigenous knowledge is even mentioned in the subject’s Curriculum, Assessment Policy Statement (CAPS); and, (iii) her limited understanding of the concept of indigenous knowledge meant that she did not to know how she could integrate indigenous knowledge into the teaching of graphic design. She also did not capitalise on indigenous knowledge as a resource in a resource-hungry teaching environment that she faced. While she acknowledged the importance of the learners’ culture, she did not take full advantage thereof in her teaching. Her adoption of demonstration as her predominant teaching approach provided an opportunity for integrating indigenous knowledge and skills but, again, she did not capitalise on that opportunity fully. This study can help transform the teaching of Technology by ensuring the integration of indigenous knowledge into the teaching of graphic design, a much-needed approach to education in the (South) African context. / Lesifundvo sinye, lesichazako sihlola kufakwa kwelwati lwebuchwepheshe nemakhono eluhlelwenitifundvo Lwebuchwepheshe esikolweni seSigodzi saseNhlanzeni eSifundzeni saseMpumalanga. Kuloku, thishela nemfundzi wesifundvo sebuchwepheshe welibanga 9 babe nencenye kulesifundvo lesifuna kubona kutsi kufakwa kwelwati lwendzabuko nemakhono kungatfutfukisa kuvisisa kwemfundzi likhono lekuhlanganisa titfombe nemfanekiso, lokuyincenye yengcikitsi lefundziswa eSifundvweni seBuchwepheshe Technology teacher and learners participated in a study seeking to determine how the integration of indigenous knowledge and skills can help to promote learners’ understanding of graphic design, which forms part of the content taught in Technology Education. Lwati lwebuchwepheshe nemakhono losekuvele kukhona encenyeni yendzabuko leyo linyenti lebafundzi lebeta, baphindza bayisebentisa lokwenta kufundza ngemakhona etitfombe nemifanekiso kwekubili kufaneleke kuphindze kuvisiseke kakhulu. Ngenca yalesizatfu, thishela munye wesifundvo seBuchwepheshe weLibanga 9 wakhetfwa ngenhloso kute ahlolwe ngemibuto, aphindze acashelwe lapho afundzisa. Bafundzi labaSikhombisa kuleliklasi lalothishela bakhetfwa kute bahlolwe ngemibuto, lokwatsi emva kwaloko ledatha yahlatiywa. Ngekusebentisa ithiyori yemcambititayela yekufundza kute kwetiwe luhlaka lwalesifundvo, lokutfoliwe kuveta kutsi, nakuba thishela anekuvisisa lokutsite ngebuchwepheshe, (i) unebumatima ngemcondvo welwati lwendzabuko; (ii) bekangati nekutsi lwati lwendzabuko kukhulunywa ngalo esifundvweni seCurriculum Assessment Policy Statement (CAPS); nekutsi (iii) lwati lwakhe lolulinganiselwe ngemcodvo welwati lwendzabuko kusho kutsi akakwati kukufaka lapho afundzisa likhono lekuhlanganisa titfombe nemifanekiso. Amange asebentise lwati lwendzabuko kutsi lumsite njengemtfombo wesimondzawo sekulambela kufundzisa lebekabukene naso. Nakuba akuvuma kubaluleka kwemasiko ebafundzi bakhe, amange akusebentise kutsi kumsite ekufundziseni kwakhe. Kusebentisa kufanekisa njengendlela legcame kakhulu ekufundziseni kwakhe kumnike litfuba lekufaka lwati lwendzabuko nemakhono, kodvwa, futsi, amange akusebentise kute kumsite. Lokutfolwe kulesifundvo kungasita ekushintjeni kufundzisa sifundvo seBuchwepheshe, ngekuciniseka kutsi kufakwa lwati lwendzabuko ekufundziseni emakhono ekuhlanganisa titfombe nemifanekiso – lokuyintfo ledzingeka kakhulu emfundvweni nemcodvo we (Ningizimu) ne-Afrika. / Leli rhubhululo elilodwa elihlathululako elisasibonelo beliphenya ngokuhlanganiswa kwelwazi kanye namakghonofundwa wendabuko asagrafu kukharikhyulamu yeThekinoloji yesikolo esisesiPhandeni seHlanzeni esiFundeni seMpumalanga. Ukufika lapha. utitjhere wakwaGreyidi 9 kanye nabafundi bazibandakanye kurhubhululo elifuna ukuthola ukobana ukuhlanganiswa kwelwazi namakghonofundwa kungasiza bunjani ekuthuthukiseni ilwazi labafundi malungana nokudizayinwa kwamagrafiki (graphic design), okuyinto eyingcenye yommongo ofundiswa eFundweni yeThekonoloji. Ilwazi kanye namakghonofundwa wegrafiki sele akhona ngaphakathi kobujamo bendabuko, kukulapho abafundi abanengi beza khona, kanti bangasebenza ukobana benze ukufundwa kwedizayini yegrafiki ukobana kukhambisane neendingo zabafundi begodu kuzwisiseke. Yeke-ke ngalesi sizathu, utitjhere munye wakwa Greyidi 9 weThekinoloji wakhethwa ngehloso ukobana abuzwe ngehlolombono, ngemva kwalokho idatha yoke yahlathululwa. Ngokulandela ithiyori i-constructivist theory yokufunda ngokwesakhiwo serhubhululo leli, okutholakeleko kwaveza ukobana, nanyana utitjhere bekanelwazi lethekinoloji, y, (i) bekakalukana nokuzwisisa amagama amalungana nelwazi lendabuko; (ii) bekangakatjheji ukobana ilwazi lendabuko khelavezwa kuSitatimende soMthethomgomo seKharikhyulamu yezokuHlola (Curriculum Assessment Policy Statement (CAPS)) yesifundo; begodu (iii) ukuzwisisa kwakhe kancani igama lelwazi lendabuko bekutjho ukobana bekangazi ukobana ilwazi leli bekangalihlanganisa bunjani nokufundisa ukudizayinwa kwegrafiki. Njengombana wabuka ukuqakatheka kwesikopilo labafundi, akhange asebenzise ngokuzeleko ithuba eliveleko lokha nakafundisako. Ukulandela kwakhe indlela yokufundisa ngokukhombisa njengendlela ejayelekileko yokufundisa kulethe ithuba lokuhlanganisa ilwazi kanye namakghonofundwa wendabuko, kanti, begodu, akhange abambelele kilokho. Okutholakeleko kileli rhubhululo kungasiza ukutjhugulula ukufundiswa kweThekinoloji, ngokuqinisekisa ukuhlanganiswa kwelwazi lendabuko ngokudizayinwa kwegrafiki – okuyindlela edingeka khulu efundweni ngaphasi kobujamo beSewula Afrika. / Curriculum and Instructional Studies / M. Ed. (Curriculum Studies)
79

Systematic Analysis and Comparison of Stress Minimizing Notch Shapes : Obtaining a stress concentration factor of Kt=1 without FEM-Code

Ciomber, Isabelle, Jakel, Roland 08 May 2014 (has links)
Als Stand der Technik sind einfache, kreisförmige Verrundungen zur Reduktion von Kerbspannungen an Querschnittsübergängen bekannt, für die aus Tabellenwerken / Diagrammen in der Literatur die Formzahl einfach abgelesen werden kann. Die Effizienz der Spannungsreduktion solcher Lösungen ist jedoch sehr begrenzt. Ziel der Arbeit ist es daher, dem Konstrukteur bzw. Berechnungsingenieur ein Verfahren in die Hand zu geben, mit dem er für Standardquerschnittsübergänge und Standardlastfälle "Nicht-Kreiskerben" ohne teure und zeitaufwendige FEM-Analyse einfach durch Nutzung geeigneter Formzahldiagramme auslegen kann. Dabei sind sogar Formzahlen von nahezu eins möglich, d.h., in der "Kerbe" bleibt praktisch nur noch die Nennspannung übrig. Die Präsentation ist zweitgeteilt: Im ersten Teil werden die Arbeitsmethoden bzw. Softwarefunktionen und verwendeten Softwarewerkzeuge vorgestellt: Dies sind die Programme Creo Parametric als vollparametrisches CAD-Werkzeug und Creo Simulate als p-FEM-Programm der Parametric Technology Coprporation (PTC). Der zweite Teil der Präsentation beschreibt den Gültigkeitsbereich sowie die untersuchten Kerbgeometrien: Die einfache kreisförmige Verrundung als Stand der Technik, die Zwei-Radien-Kerbe, die Baud-Kurve, die Methode der Zugdreiecke nach Claus Mattheck, die elliptische Kerbe sowie die konische Rundung als generalisierte elliptische Kerbe. Es wird kurz eine Bibliothek vorgestellt, mit der solche Kerben einfach ausgelegt werden können, d.h. Ihre exakte Geometrie festgelegt sowie die zugehörige Formzahl αk bestimmt werden kann. / Circular (one-radius) fillets are known as state-of-the-art for reducing notch stresses at cross section transitions. The stress concentration factor Kt of such geometries can be read out from diagrams/tables given in the literature. However, the efficiency of stress reduction of circular notches is very limited. The goal of the work therefor is to present a method for the designer/analyst how to design non-circular notches/fillets just by using suitable Kt-diagrams without time-consuming and expensive FEM analyses. Kt-numbers of nearly one are possible, that means in the "notch" just the nominal stress appears and no stress concentration takes place. The presentation has two parts: Part one describes the working methods and software functions as well as software tools: Creo Parametric as fully-parametric CAD program and Creo Simulate as embedded p-FEM-tool from Parametric Technology Corporation (PTC) have been used. The second part describes the range of validity and the examined notch geometries: The one-radius fillet as state-of-the-art, the two-radii filet, the Baud-curve, the method of tensile triangles from Claus Mattheck, the standard elliptical fillet and the conical round as generalized elliptical fillet. A notch layout library is shortly presented that allows to design such fillets, that means exactly determine the notch geometry and the related stress concentration factor Kt.

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