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Elektrische Charakterisierung PLD-gewachsener Zinkoxid-NanodrähteZimmermann, Gregor 14 October 2010 (has links) (PDF)
Die vorliegende Arbeit beschäftigt sich mit der elektrischen Charakterisierung von Zinkoxid-Nanodrähten, die mittels gepulster Laserablation (PLD) hergestellt wurden.
Ausgehend von den so generierten ZnO-Nanodraht-Ensembles werden Methoden zu deren elektrischer Untersuchung diskutiert und auf praktische Anwendbarkeit hin verglichen. Die entwickelten Methoden werden auf Ensembles von auf n-leitenden ZnO- und ZnO:Ga-Dünnschichten aufgewachsenen Phosphor-dotierten ZnO-Nanodrähten angewendet. Deren reproduzierbares, in Strom–Spannungs- (I–U-) Kennlinien beobachtetes diodenartiges Verhalten wird genauer beleuchtet.
Im Zusammenhang mit der elektrischen Charakterisierung einzelner ZnO-Nano-drähte werden experimentelle Methoden zur Vereinzelung und zur Kontaktierung der vereinzelten ZnO-Nanodrähte diskutiert. Dabei werden sowohl etablierte Methoden wie Elektronenstrahllithographie (EBL) als auch neue Techniken wie elektronen- und ionenstrahlinduzierte Deposition (EBID/IBID) und Strom–Spannungs-Rastersondenmikroskopie (I-AFM) behandelt und ihre Eignung für eingehende elektrische Untersuchungen und reproduzierbare Messungen analysiert.
Die geeignetsten Methoden werden schließlich eingesetzt, um spezifischen Widerstand sowie Ladungsträgermobilität und -dichte sowohl in nominell undotierten als auch in Aluminium-dotierten ZnO-Nanodrähten zu untersuchen und zu vergleichen. In der Ableitung der physikalischen Materialparameter aus den Messdaten wird dabei besonderes Augenmerk auf die Einbeziehung der geometrischen Besonderheiten der Nanodrähte gegenüber Volumenmaterial- und Dünnschichtproben gelegt. Im Zuge dessen wird unter anderem ein Modell für den elektrischen Widerstand in Nanodrähten mit ihrer Länge nach veränderlichem Querschnitt abgeleitet.
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Elektrische Charakterisierung PLD-gewachsener Zinkoxid-NanodrähteZimmermann, Gregor 17 August 2010 (has links)
Die vorliegende Arbeit beschäftigt sich mit der elektrischen Charakterisierung von Zinkoxid-Nanodrähten, die mittels gepulster Laserablation (PLD) hergestellt wurden.
Ausgehend von den so generierten ZnO-Nanodraht-Ensembles werden Methoden zu deren elektrischer Untersuchung diskutiert und auf praktische Anwendbarkeit hin verglichen. Die entwickelten Methoden werden auf Ensembles von auf n-leitenden ZnO- und ZnO:Ga-Dünnschichten aufgewachsenen Phosphor-dotierten ZnO-Nanodrähten angewendet. Deren reproduzierbares, in Strom–Spannungs- (I–U-) Kennlinien beobachtetes diodenartiges Verhalten wird genauer beleuchtet.
Im Zusammenhang mit der elektrischen Charakterisierung einzelner ZnO-Nano-drähte werden experimentelle Methoden zur Vereinzelung und zur Kontaktierung der vereinzelten ZnO-Nanodrähte diskutiert. Dabei werden sowohl etablierte Methoden wie Elektronenstrahllithographie (EBL) als auch neue Techniken wie elektronen- und ionenstrahlinduzierte Deposition (EBID/IBID) und Strom–Spannungs-Rastersondenmikroskopie (I-AFM) behandelt und ihre Eignung für eingehende elektrische Untersuchungen und reproduzierbare Messungen analysiert.
Die geeignetsten Methoden werden schließlich eingesetzt, um spezifischen Widerstand sowie Ladungsträgermobilität und -dichte sowohl in nominell undotierten als auch in Aluminium-dotierten ZnO-Nanodrähten zu untersuchen und zu vergleichen. In der Ableitung der physikalischen Materialparameter aus den Messdaten wird dabei besonderes Augenmerk auf die Einbeziehung der geometrischen Besonderheiten der Nanodrähte gegenüber Volumenmaterial- und Dünnschichtproben gelegt. Im Zuge dessen wird unter anderem ein Modell für den elektrischen Widerstand in Nanodrähten mit ihrer Länge nach veränderlichem Querschnitt abgeleitet.
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Fallstudie om Prediktivt och Tillståndsbaserat Underhåll inom Läkemedelsindustrin / Case study regarding Predictive and Condition-based Maintenance in the Pharmaceutical IndustryRedzovic, Numan, Malki, Anton January 2022 (has links)
Underhåll är en aktivitet som varje produktion vill undvika så mycket som möjligt på grund av kostnaderna och tiden som anknyts till den. Trots detta så är en väl fungerande underhållsverksamhet väsentlig för att främja produktionens funktionssäkerhet och tillgänglighet att tillverka. En effektiv underhållsorganisation går däremot inte ut på att genomföra mer underhåll än vad som egentligen är nödvändigt utan att genomföra underhåll i rätt tid. På traditionellt sätt så genomförs detta genom att ersätta slitage delar och serva utrustningen med fastställda mellanrum för att förebygga att haveri, vilket kallas för förebyggande underhåll. De tidsintervaller som angivits för service bestäms av leverantörerna och grundar sig i en generell uppskattning av slitagedelarnas livslängd utifrån tester och analys. Till skillnad från att köra utrustningen till den går sönder som kallas för Avhjälpande underhåll så kan underhåll genomföras vid lämpliga tider så att det inte påverkar produktion och tillgänglighet. Men de tidsintervall som leverantörerna rekommenderar till företagen garanterar inte att slitage delen håller sig till det intervallet, delarna kan exempelvis rasa tidigare än angivet eller till och med hålla längre. Av denna anledning är det naturliga steget i underhållets utveckling att kunna övervaka utrustningens hälsa i hopp om att kunna förutspå när och varför ett haveri ska uppstå. Den här typen av underhåll kallas för tillståndsbaserat och prediktivt underhåll och medför ultimat tillgänglighet av utrustning och den mest kostnadseffektiva underhållsorganisationen, då god framförhållning och översikt uppnås för att enbart genomföra underhåll när det behövs. Det som gör tillståndsbaserat och prediktivt underhåll möjligt är den fjärde industriella revolutionen “Industri 4.0” och teknologierna som associeras med den som går ut på absolut digitalisering av produktionen och smarta fabriker. Teknologier som IoT, Big Dataanalys och Artificiell Intelligens används för att koppla upp utrustning till nätet med hjälp av givare för att samla in och lagra data som ska användas i analyser för att prognosera dess livslängd. Uppdragsgivaren AstraZeneca i Södertälje tillverkar olika typer av läkemedel som många är livsviktiga för de patienter som tar dessa mediciner. Om AstraZenecas produktion står still på grund av fel i utrustningen kommer det inte enbart medföra stora ekonomiska konsekvenser utan även påverka de människor som med livet förlitar sig på den medicin som levereras. För att försäkra produktionens tillgänglighet har AstraZeneca gjort försök att tillämpa tillståndsbaserat och prediktivt underhåll men det är fortfarande enbart i startgroparna. Eftersom ventilation är kritisk del av AstraZeneca produktion då ett fel i ventilationssystemet resulterar i totalt produktionsstopp i byggnaden förens problemet åtgärdas och anläggningen sanerats blev det även rapportens fokusområde. Arbetets uppgift går därför ut på att undersöka möjligheter för AstraZeneca att utveckla deras prediktiva och tillståndsbaserat underhåll på deras ventilationssystem, för att sedan kunna identifiera och presentera förslag på åtgärder. Dessa förslag analyserades sedan med hjälp av verktygen QFD-Matris och Pugh-Matris för att kunna uppskatta vilket förslag som är mest kostnadseffektivt, funktions effektivt samt vilket förslag som kommer tillföra mest nytta för underhållet på AstraZeneca. / Maintenance is an activity that every production wants to avoid as much as possible due to the costs and the time associated with it. Despite this, a well-functioning maintenance operation is essential to promote the production's availability to manufacture and operational reliability. Running an efficient maintenance operation is not about carrying out more maintenance than is necessary but carrying out the right amount of maintenance at the right time. Traditionally speaking this is done by replacing worn parts and servicing the equipment at set intervals to prevent breakdowns, this method is called preventive maintenance. The intervals specified for service are determined by the suppliers and are based on general estimates of the service life for the spare parts from test and analytics. Preventive maintenance allows for maintenance to be carried out at appropriate time to not affect production and availability unlike running the equipment until breakdown, which is called reactive maintenance. However, these intervals that the suppliers recommend do not guarantee that the parts adhere to the given interval, the part can for example break down earlier than expected or even outlast its prescribed lifetime. Because of this, the natural step in the development of maintenance is giving companies the ability to monitor the health of the equipment in hope of being able to predict potential breakdowns. This is what Condition-Based and predictive maintenance is and it provides the ultimate availability of equipment and the most cost-effective maintenance organization, because the good foresight and overview allows maintenance to be carried out only when needed. The fourth industrial revolution “Industry 4.0”, absolute digitalization of production, smart factories and all the technologies associated with this is what makes this type of maintenance possible. Technologies such as IoT, Big Data Analytics and Artificial Intelligence are used to connect equipment to the network using sensors so that data can be stored and collected to be analyzed to forecast the lifespan of parts and equipment. AstraZeneca in Södertälje manufactures different types of medicine, many of which are vital for the patients who take them. If their production comes to a standstill due to equipment failure, it will not only have major financial consequences but also greatly affect the people who rely on the medicine offered with their lives. To ensure the availability of production, AstraZeneca has made attempts to apply condition-based and predictive maintenance, but it is still only in its infancy. Since ventilation is a critical part of AstraZeneca's production, as a failure here will result in a total production stoppage for the building affected and will not resume before the problem is remedied and the plant is decontaminated, it also became the report's focus area. The task at hand is therefore to investigate the opportunities AstraZeneca must develop their predictive and condition-based maintenance for their ventilation systems, in order to be able to present proposals for measures. The proposals will then be analyzed using tools like the QFD-Matrix and the Pugh-Matrix in order to estimate which is more cost effective, function effective and which one will bring the most benefit to AstraZeneca.
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The development of the “Sudan Pionier Mission” into a mission among the Nile-Nubians (1900-1966)Lauche, Gerald 02 1900 (has links)
This study deals with modern mission history in north eastern Africa. When the rigid Islamistic Mahdi regime in the Sudan was defeated by an Anglo-Egyptian army in 1898, H G Guinness and K Kumm came to Aswan and initiated the Sudan Pionier Mission (SPM) in 1900. The SPM had its spiritual roots in the Holiness Movement and became an interdenominational German-based faith mission. Although the SPM was started in Aswan to advance from there to the south to evangelize animistic people groups in the Eastern Sudan, the SPM actually consolidated its work in and around Aswan for internal and external reasons. Thus, the focus of the SPM shifted from an animistic to an Islamic audience with a special emphasis on the Nile-Nubians occupying the Nile valley between Aswan and Dongola. This study contributes generally to the historiography of the SPM between 1990 until 1966 and analyzes especially the development of the SPM into a mission among the Nile-Nubians during this period. The ethnic groups of the Nile-Nubians will be introduced and their historical, political, social, economic, linguistic and religious situation will be presented. This thesis further describes the topographical development of the SPM and its missiological approach. A special emphasis is given to the life story of the Kunuuzi Nubian convert Samu’iil Ali Hiseen (SAH-1863-1900) and his multifaceted contribution to the work of the SPM. SAH was the first Nubian evangelist in modern times and the major stakeholder of the Nubian vision. Neither the history of the SPM as “Nubian Mission” nor the life and work of SAH have been researched and presented before. / Christian Spirituality, Church History and Missiology / D. Th. (Missiology)
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Carrier profiling of ZnO nanowire structures by scanning capacitance microscopy and scanning spreading resistance microscopy / Profilage porteur de structures de nanofils ZnO par microscopie à capacité de balayage et microscopie à dispersionWang, Lin 28 April 2016 (has links)
Ce travail de thèse porte sur l'application des techniques Scanning Capacitance Microscopy (SCM) et Scanning Spreading Resistance Microscopy (SSRM) pour la caractérisation électrique de nanofils de ZnO avec l'objectif d'en déterminer le dopage par profilage des porteurs libres suite à des essais de dopage de type p. Afin de pouvoir utiliser un référentiel planaire nécessaire à ces mesures par sonde locale, un procédé de remplissage par dip-coating et de polissage a été spécialement développé sur des champs de nanofils quasi-verticaux. De plus, dans le but de parvenir à un étalonnage des mesures SCM et SSRM, nous avons conçu et fait fabriquer des échantillons étalons de dopage de type n, contenant des niveaux de Ga en escalier de densité variable de 2×10^17 à 3×10^20 cm^-3. Les mesures sur des coupes transversales de ces deux de structures multicouches ont permis, pour la première fois sur ZnO d'établir un étalonnage des mesures SCM et SSRM et de déterminer le dopage intrinsèque électriquement actif de couches 2D nanométriques, résultat difficilement atteignable par d'autres techniques d'analyse. Des résultats inattendus de concentration résiduelle de porteur de l'ordre de 2×10^18 et 3×10^18 cm^-3 ont été trouvés sur les nanofils de ZnO crus par MOCVD et par CBD respectivement. Outre la caractérisation électrique microscopique des nanofils par SCM et SSRM, des techniques macroscopiques classiques ont été utilisées pour caractériser des assemblées importantes de nanofils de ZnO. L'origine de la difference entre les résultats de deux genres de technique a été discutée. Nous avons aussi étudié les effets des dopages ex-situ par diffusion du phosphore (procédé SOD) et des dopages in situ par incorporation d'antimoine (Sb) pendant la croissance MOCVD. Les résultats majeurs sont obtenus pour l'antimoine, en utilisant des couches ZnO: Sb 2D et des nanofils cœur-coquille ZnO/ZnO: Sb, ou l'hypothèse d'une compensation partielle du dopage n résiduel par un centre accepteur créé par le dopage Sb semble pouvoir être établie raisonnablement. / Based on atomic force microscope (AFM), scanning capacitance microscopy (SCM) and scanning spreading resistance microscopy (SSRM) have demonstrated high efficiency for two dimensional (2D) electrical characterizations of Si semiconductors at nanoscale and then have been extensively employed in Si-based structures/devices before being extended to the study of some other semiconductor materials. However, ZnO, a representative of the third generation semiconductor material, being considered a promising candidate for future devices in many areas, especially in opto-electronic area, has rarely been addressed. Recently, extensive research interests have been attracted by ZnO NWs for future devices such as LED, UV laser and sensor. Therefore, a good understanding of electrical properties of the NWs is in need. In this context, this thesis work is dedicated to the 2D electrical characterization of ZnO NWs with the focus of carrier profiling on this kind of nanostructure in the effort of their p-type doping. For this purpose, a planarization process has been developed for the NWs structure in order to obtain an appropriate sample surface and perform SCM/SSRM measurements on the top of the NWs. For quantitative analysis, Ga doped ZnO multilayer staircase structures were developed serving as calibration samples. Finally, residual carrier concentrations inside the CBD and MOCVD grown ZnO NWs are determined to be around 3×10^18 cm^-3 and 2×10^18 cm^-3, respectively. The results from SCM/SSRM characterization have been compared with that from macroscopic C-V measurements on collective ZnO NWs and the differences are discussed. In addition to carrier profiling on NWs structure, applications of SCM/SSRM on some other ZnO-based nanostructures are also investigated including ZnO:Sb films, ZnO/ZnO:Sb core-shell NWs structure, ZnO/ZnMgO core-multishell coaxial heterostructures.
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The development of the “Sudan Pionier Mission” into a mission among the Nile-Nubians (1900-1966)Lauche, Gerald 02 1900 (has links)
This study deals with modern mission history in north eastern Africa. When the rigid Islamistic Mahdi regime in the Sudan was defeated by an Anglo-Egyptian army in 1898, H G Guinness and K Kumm came to Aswan and initiated the Sudan Pionier Mission (SPM) in 1900. The SPM had its spiritual roots in the Holiness Movement and became an interdenominational German-based faith mission. Although the SPM was started in Aswan to advance from there to the south to evangelize animistic people groups in the Eastern Sudan, the SPM actually consolidated its work in and around Aswan for internal and external reasons. Thus, the focus of the SPM shifted from an animistic to an Islamic audience with a special emphasis on the Nile-Nubians occupying the Nile valley between Aswan and Dongola. This study contributes generally to the historiography of the SPM between 1990 until 1966 and analyzes especially the development of the SPM into a mission among the Nile-Nubians during this period. The ethnic groups of the Nile-Nubians will be introduced and their historical, political, social, economic, linguistic and religious situation will be presented. This thesis further describes the topographical development of the SPM and its missiological approach. A special emphasis is given to the life story of the Kunuuzi Nubian convert Samu’iil Ali Hiseen (SAH-1863-1900) and his multifaceted contribution to the work of the SPM. SAH was the first Nubian evangelist in modern times and the major stakeholder of the Nubian vision. Neither the history of the SPM as “Nubian Mission” nor the life and work of SAH have been researched and presented before. / Christian Spirituality, Church History and Missiology / D. Th. (Missiology)
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Porovnání metod efektivní a funkční konektivity ve funkční magnetické rezonanci / A comparison of effective and functional connectivity methods in fMRIGajdoš, Martin January 2012 (has links)
Functional magnetic resonance imaging (fMRI) is recent important method, used in neuroimaging. The aim of this thesis is to develop software tool for comparison of two methods for functional and effective connectivity estimation. In this thesis are described the basics of magnetic resonance imaging, fMRI, basic terms of fMRI experiments and generally are described methods of functional and effective connectivity. Then are more detailed mentioned methods of dynamic causal modeling (DCM), Granger causal modeling (GCM) and independent component analysis (ICA). Practical implementation of DCM in toolbox SMP and ICA in toolbox GIFT is also mentioned. In purpose to describe behavior of DCM and GCM in dependence on several parameters are performed Monte Carlo simulations. Then the concept and realization of software tool for simulating connectivity and comparison of DCM and GCM are described. Finally results of DCM and GCM comparison and results of Monte Carlo simulations are discussed.
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THE ROLE OF NATIVE POINT DEFECTS AND SURFACE CHEMICAL REACTIONS IN THE FORMATION OF SCHOTTKY BARRIERS AND HIGH N-TYPE DOPING IN ZINC OXIDEDoutt, Daniel R. 08 August 2013 (has links)
No description available.
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Critical perspectives: North Sea offshore wind farms. : Oral histories, aesthetics and selected legal frameworks relating to the North Sea. / Kritiska perspektiv: vindkraftparker i Nordsjön : Muntlig historia, estetik och utvalda rättsliga ramar relaterade till NordsjönMoss, Joanne January 2021 (has links)
The study is developed from five in-depth interviews with individuals from different walks of life who have interacted significantly with the North Sea. The study discusses change in the North Sea specifically in the development of fixed turbine wind farms and their physical and aesthetic effects. Observations speakers make as to changes in the North Sea and as to its beauty are contextualised and discussed using NASA satellite images, photographs and review of available academic literature, UK policy documents and law. This context includes a study of the industrialised North Sea with reference to the sediment sea plumes behind monopile turbines. The United Kingdom was selected for particular study of its wind farm development permissions process, including evaluations of seascape and the requirement of independence for expert evidence. Decline of trawler access to the North Sea is referenced to wind farm growth, and to adverse changes in public opinion leading to closure of the UK Dogger Bank to trawlers. Finality of wind farm development decisions is considered against the prospect of overturn by the courts. This aspect covers the application and development of principles relating to appeal by way of judicial review in the UK jurisdictions of Scotland, England and Wales, and Northern Ireland. The study identifies, and explains the English aesthetic evaluation of wind farms. It concludes that sea plumes are the result of a legal choice to allow permit applications to succeed without testing by reference to detailed in-sea turbine dimensions. In the permissions process (a) sea plumes are not evaluated by the seascape criteria applicable to coastal or off-coastal wind farms (b) deep offshore wind farms are instead evaluated by possible changes to character of the sea. The study further concludes that (i) the open horizon of the North Sea has been lost in significant part (ii) the combined aesthetic of transience, decay, and nostalgia underlies the aesthetic of the North Sea Maunsell forts (contrasted to Sealand), and also underlies attitudes to decommissioning wind farms, and (iii) concepts of sea beauty may be based on appearance or health, being regulated by different legal regimes in each eventuality (respectively the European Landscape Convention, or the OSPAR/ biodiversity/ habitat initiatives)
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Applied Drama in English Language LearningMohd Nawi, Abdullah January 2014 (has links)
This thesis is a reflective exploration of the use and impact of using drama pedagogies in the English as a Second Language (ESL)/ English as a Foreign Language (EFL) classroom. It stems from the problem of secondary school English language learning in Malaysia, where current teaching practices appear to have led to the decline of the standard of English as a second language in school leavers and university graduates (Abdul Rahman, 1997; Carol Ong Teck Lan, Anne Leong Chooi Khaun, & Singh, 2011; Hazita et al., 2010; Nalliah & Thiyagarajah, 1999). This problem resonates with my own experiences at school, as a secondary school student, an ESL teacher and, later, as a teacher trainer. Consequently, these experiences led me to explore alternative or supplementary teaching methodologies that could enhance the ESL learning experience, drawing initially from drama techniques such as those advocated by Maley and Duff (1983), Wessels (1987), and Di Pietro (1983), and later from process drama pedagogies such as those advocated by Greenwood (2005); Heathcote and Bolton (1995); Kao and O'Neill (1998), and Miller and Saxton (2004). This thesis is an account of my own exploration in adapting drama pedagogies to ESL/EFL teaching. It examines ways in which drama pedagogies might increase motivation and competency in English language learning.
The main methodology of the study is that of reflective practice (e.g. Griffiths & Tann, 1992; Zeichner & Liston, 1996). It tracks a learning journey, where I critically reflect on my learning, exploring and implementing such pedagogical approaches as well as evaluate their impact on my students’ learning. These critical reflections arise from three case studies, based on three different contexts: the first a New Zealand English for Speakers of Other Languages (ESOL) class in an intermediate school, the second a Malaysian ESL class in a rural secondary school, and the third an English proficiency class of adult learners in a language school. Data for the study were obtained through the following: research journal and reflective memo; observation and field notes; interview; social media; students’ class work; discussion with co-researchers; and through the literature of the field.
A major teaching methodology that emerges from the reflective cycles is that of staging the textbook, where the textbook section to be used for the teaching programme is distilled, and the key focuses of the language, skills, vocabulary, and themes to be learnt are identified and extracted. A layer of drama is matched with these distilled elements and then ‘staged’ on top of the textbook unit, incorporating context-setting opportunities, potential for a story, potential for tension or complication, and the target language elements.
The findings that emerge through critical reflection in the study relate to the drama methodologies that I learn and acquire, the impact of these methodologies on students, the role of culture in the application of drama methodologies, and language learning and acquisition. These findings have a number of implications. Firstly, they show how an English Language Teaching (ELT) practitioner might use drama methodologies and what their impact is on student learning. While the focus is primarily on the Malaysian context, aspects of the findings may resonate internationally. Secondly, they suggest a model of reflective practice that can be used by other ELT practitioners who are interested in using drama methodologies in their teaching. Thirdly, these findings also point towards the development of a more comprehensive syllabus for using drama pedagogies, as well as the development of reflective practice, in the teacher training programmes in Malaysia.
The use of drama pedagogies for language learning is a field that has not been researched in a Malaysian context. Therefore, this account of reflective practice offers a platform for further research and reflection in this context.
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