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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.
221

Electronic Coupling Effects and Charge Transfer between Organic Molecules and Metal Surfaces

Forker, Roman 12 January 2010 (has links)
We employ a variant of optical absorption spectroscopy, namely in situ differential reflectance spectroscopy (DRS), for an analysis of the structure-properties relations of thin epitaxial organic films. Clear correlations between the spectra and the differently intense coupling to the respective substrates are found. While rather broad and almost structureless spectra are obtained for a quaterrylene (QT) monolayer on Au(111), the spectral shape resembles that of isolated molecules when QT is grown on graphite. We even achieve an efficient electronic decoupling from the subjacent Au(111) by inserting an atomically thin organic spacer layer consisting of hexa-peri-hexabenzocoronene (HBC) with a noticeably dissimilar electronic behavior. These observations are further consolidated by a systematic variation of the metal substrate (Au, Ag, and Al), ranging from inert to rather reactive. For this purpose, 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) is chosen to ensure comparability of the molecular film structures on the different metals, and also because its electronic alignment on various metal surfaces has previously been studied with great intensity. We present evidence for ionized PTCDA at several interfaces and propose the charge transfer to be related to the electronic level alignment governed by interface dipole formation on the respective metals. / Zur Analyse der Struktur-Eigenschafts-Beziehungen dünner, epitaktischer Molekülfilme wird in situ differentielle Reflexionsspektroskopie (DRS) als Variante der optischen Absorptionsspektroskopie verwendet. Klare Zusammenhänge zwischen den Spektren und der unterschiedlich starken Kopplung zum jeweiligen Substrat werden gefunden. Während man breite und beinahe unstrukturierte Spektren für eine Quaterrylen (QT) Monolage auf Au(111) erhält, ist die spektrale Form von auf Graphit abgeschiedenem QT ähnlich der isolierter Moleküle. Durch Einfügen einer atomar dünnen organischen Zwischenschicht bestehend aus Hexa-peri-hexabenzocoronen (HBC) mit einem deutlich unterschiedlichen elektronischen Verhalten gelingt sogar eine effiziente elektronische Entkopplung vom darunter liegenden Au(111). Diese Ergebnisse werden durch systematische Variation der Metallsubstrate (Au, Ag und Al), welche von inert bis sehr reaktiv reichen, untermauert. Zu diesem Zweck wird 3,4,9,10-Perylentetracarbonsäuredianhydrid (PTCDA) gewählt, um Vergleichbarkeit der molekularen Filmstrukturen zu gewährleisten, und weil dessen elektronische Anordnung auf verschiedenen Metalloberflächen bereits eingehend untersucht worden ist. Wir weisen ionisiertes PTCDA an einigen dieser Grenzflächen nach und schlagen vor, dass der Ladungsübergang mit der elektronischen Niveauanpassung zusammenhängt, welche mit der Ausbildung von Grenzflächendipolen auf den entsprechenden Metallen einhergeht.
222

Application development of 3D LiDAR sensor for display computers

Ekstrand, Oskar January 2023 (has links)
A highly accurate sensor for measuring distances, used for creating high-resolution 3D maps of the environment, utilize “Light Detection And Ranging” (LiDAR) technology. This degree project aims to investigate the implementation of 3D LiDAR sensors into off-highway vehicle display computers, called CCpilots. This involves a study of available low-cost 3D LiDAR sensors on the market and development of an application for visualizing real time data graphically, with room for optimization algorithms. The selected LiDAR sensor is “Livox Mid-360”, a hybrid-solid technology and a field of view of 360° horizontally and 59° vertically. The LiDAR application was developed using Livox SDK2 combined with a C++ back-end, in order to visualize data using Qt QML as the Graphical User Interface design tool. A filter was utilized from the Point Cloud Library (PCL), called a voxel grid filter, for optimization purpose. Real time 3D LiDAR sensor data was graphically visualized on the display computer CCpilot X900. The voxel grid filter had a few visual advantages, although it consumed more processor power compared to when no filter was used. Whether a filter was used or not, all points generated by the LiDAR sensor could be processed and visualized by the developed application without any latency.
223

Environmental Inequalities in the Anthropocene

Schuster, Antonia 17 June 2024 (has links)
Die Dissertation beleuchtet die dringende Notwendigkeit, Maßnahmen zu ergreifen, um den Druck auf die Ressourcen der Erde zu mindern und nachhaltige Bedingungen für gegenwärtige und künftige Generationen zu schaffen. Zwei zentrale Strategien werden diskutiert: Die Dekarbonisierung von Energiesystemen und die Reduktion der Emissionen von Haushalten. Diese Strategien sind eng mit Fragen von Gerechtigkeit verbunden, sowohl im Zusammenhang mit einer gerechten Energiewende als auch in der Emissionsminderung von Haushalten. Die Dissertation besteht aus vier Artikeln, die diese Themen vertiefen. Die erste untersucht den Kohleausstieg in europäischen Regionen und die Wahrnehmung der Energiewende durch die davon betroffenen Menschen. Die nächsten beiden untersuchen die Emissionsreduktion auf Haushaltsebene, wobei die sozialen Realitäten der Emittenten analysiert werden, um Reduktionspotenziale zu identifizieren. Die vierte Publikation bietet einen historischen Überblick über Energiekonsummuster und zeigt vergangene und bestehenden Ungleichheiten auf. Die Ergebnisse zeigen, dass die Klimakrise nur unter Berücksichtigung von Ungleichheiten und Ungerechtigkeiten verstanden und angegangen werden kann. Lösungen müssen darauf abzielen, weitere Ungerechtigkeiten zu vermeiden. Die Ergebnisse der Dissertation bieten unter anderem wertvolle Erkenntnisse für Entscheidungsträger auf verschiedenen Ebenen, um eine gerechte Transformation zu klimaneutralen Gesellschaften voranzutreiben. Es wird jedoch betont, dass weitere Forschung in diesen Bereichen, einschließlich anderer fossiler Energieträger und betroffener Regionen, sowie unterschiedlicher Lebensstile, entscheidend ist, um effektive Instrumente zur Unterstützung nachhaltiger Praktiken zu entwickeln. / The dissertation underscores the urgent need to address the strain human activities place on the Earth system, emphasizing the necessity for sustainable solutions to ensure the well-being of current and future generations. Mitigating the impacts of the climate crisis requires significant reductions in greenhouse gas emissions, prompting a closer examination of their sources and contributors. Two primary strategies are proposed: decarbonizing energy systems and reducing household emissions. However, discussions surrounding these strategies often intersect with considerations of justice, highlighting the complex social dimensions of addressing climate change. The dissertation comprises four papers that delve into these issues. The first explores the transition away from coal in European regions, assessing perceptions of justice among affected actors. The subsequent publications focus on emissions reduction at the household level, analyzing social realities and identifying potential avenues for mitigation. The final publication provides a historical perspective on energy consumption patterns, emphasizing past and contemporary societal inequalities. Findings indicate disparities in emissions across households and individuals, necessitating urgent action to reduce per capita emissions. Moreover, sociological frameworks are employed to better understand the ecological dimensions of emissions, revealing complex relationships between social classes and environmental impact. While efforts to combat the climate crisis must prioritize justice and equity, the dissertation also underscores the need for further research. This includes examining alternative energy sources, regions disproportionately affected by climate change, as well as diverse lifestyles. Such research will be essential for developing effective strategies to support sustainable practices and address the complex social dynamics of climate action.
224

Extended Bluetooth Profiles on CCpilot displays

Johnson, Alexander January 2017 (has links)
Bluetooth is used in modern cars to connect smartphones to stream music, to access internet and for phone services such as phone book contacts and making calls. Similar features are now requested by customers of maximatecc's products, e.g. display computers, for offroad vehicles. This thesis is aimed to investigate what is needed to support these features in maximatecc's Linux based displays and how the features can be used in a Qt application. For instance, the connectivity features in personal cars most commonly utilizes the Bluetooth profiles: Advanced Audio Distribution Profile (A2DP) Audio/Video Remote Control Profile (AVRCP) Personal Area Network (PAN) Profile Hands Free Profile (HFP) Phone Book Access Profile (PBAP) Message Access Profile (MAP). In Linux operating system the Bluetooth stack Bluez is used in the lower level implementation. Open source software components recommended to implement the above profiles includes: Obexd (for MAP and PBAP) PulseAudio (for A2DP and HFP) oFono (for HFP) Connman (for PAN) all of which help to implement the top level profiles of the Bluetooth stack needed, easily controlled by a Qt application through DBus. Most of the external software components were not possible to add to the Linux image on the CCpilot VA display during the period of the thesis. Instead some features of the profiles have been tested, through a Qt demo and python test scripts, on a Virtual Machine in an environment similar to the CCpilot VA. All profiles tested had some functionality verified except for AVRCP, which is not supported until later versions of Bluez, not available for the Linux kernel on the CCpilot VA. However, the audio in the HFP only occasionally worked. On the CCpilot VA only PBAP was tested successfully.
225

Understanding societies beyond economics

Proestou, Maria 25 April 2016 (has links)
Die gegenwärtige Politik betrachtet Windenergieanlagen als ein entscheidendes Mittel für die Gestaltung einer nachhaltigen Zukunft. Dennoch lehnen die BewohnerInnen der griechischen Insel Amorgos Anträge zum Bau von Windenergieanlagen ab. In der vorliegenden Untersuchung analysiere ich, wie die InselbewohnerInnen die Option der Windenergie beurteilen. Die Analyse basiert auf einem interdisziplinären theoretischen Ansatz und einem neu entwickelten analytischen Rahmenwerk, dem Institutions - Habits - Intuitions (IHI) framework. Qualitative Forschungsmethoden, insbesondere persönliche Befragungen und teilnehmende Beobachtungen, sind wesentliche Elemente der Datenerhebung und erlauben mir, mich umfassend in den amorgianischen Kontext zu vertiefen. Die Forschungsergebnisse zeigen, dass der Beurteilungsprozess auf dem Zusammenwirken von Kosten-Nutzen Kalkulationen, der Infragestellung der Thematik der Windenergie und intuitivem Handeln basiert. Die Option der Windenergie erschüttert die herkömmlichen Interaktionen der InselbewohnerInnen, die die lokale Tourismuswirtschaft und Gemeindeverwaltung bestimmen. Die Kombination pre-formeller Institutionen, eingefahrener Gepflogenheiten und intuitives Agierens aufgrund bisheriger Erfahrungen bringt die amorgianische Gesellschaft dazu, Windenergieprojekte abzulehnen. Die Analyse beruht auf der Anwendung von Ansätzen der Sozialpsychologie und der Institutionenökonomik. Damit wird u.a. die gängige Annahme, der Mensch sei a priori ein Investor hinterfragt und die Absicht verfolgt, die Kluft zwischen Wirtschaftswissenschaften und ‘realer Welt’ zu verringern. Die Insel von Amorgos ist ein beispielhafter Mikrokosmos in und für Griechenland als Ganzes. Energiepolitische Strategien und die lokalen und nationalen Beurteilungsprozesse dieser sind dabei nur zu verstehen, wenn die mit dem Neoliberalismus zusammenhängende, tiefgreifende sozio-ökonomische Krise Griechenlands in den Blick genommen wird. / Locals of the Greek island of Amorgos refuse wind energy proposals, while contemporary politics regards wind farms as a crucial means of pursuing a sustainable future. On the basis of an interdisciplinary theoretical approach, I develop a new analytical framework called Institutions - Habits - Intuitions (IHI) framework to explain the way Amorgians judge the option of wind energy development on their island. The data collection relies on qualitative research methods, that is, face-to-face interviews and participant observations, which enable me to delve into the particular Amorgian context. The research results show that the synergy of locals’ calculation (cost-benefit analysis), reflection and intuitive action influences their deliberation on the wind energy issue. The option of wind energy development shocks the ordinary run of things on the island, which is characterised by off-the-record interactions that shape both the tourism economy and the municipal administration. The combination of local pre-formal institutions, entrenched habits and intuitive responses causes Amorgian society to resist wind farms. Analysing the Amorgian case through applying approaches derived from social psychology and institutional economics, I aim at bringing the readers of this book to reflect on the discourse on sustainability and narrowing the gap between the discipline of economics and the real world. My analysis questions the utilitarian assumption that man is a priori an investor, and goes beyond the case of Amorgos, which constitutes a microcosm of Greece, which currently experiences a deep socio-economic crisis. I draw attention to the fact that locals of Amorgos act and interact within the context of this crisis, which is related to the political economic thinking attributed to neoliberalism. Finally, I claim that increasing bureaucratisation of social life clashes with local ethics, thereby affecting responses to politics of climate change mitigation.
226

Long QT syndrome in Sweden : founder effects and associated cardiac phenotypes / Långt QT syndrom i Sverige : foundereffekter och associerade kardiella fenotyper

Winbo, Annika January 2012 (has links)
Background: We aimed to increase the knowledge regarding the familial arrhythmogenic disorder Long QT Syndrome (LQTS) and its recessive variant Jervell and Lange-Nielsen Syndrome (JLNS) in Sweden, including prevalences and clinical phenotypes. A specific focus was directed towards two KCNQ1 mutations –p.Y111C and p.R518X- commonly identified in Swedish LQTS index cases. Methods: Cases and families with LQTS (p.Y111C or p.R518X) and JLNS were recruited via regional clinical practices, national referrals to the Clinical Genetics laboratory, Umeå University Hospital, and a national inventory. Molecular genetics methods were used for case ascertainment. Clinical data was obtained via medical records, a questionnaire, and/or an interview. Electrocardiograms were manually assessed. In p.R518X heterozygotes intra-familial phenotypic variability (QTc and cardiac events) was assessed by analysis of sequence variants (modifier genes). The origins of the mutations p.Y111C and p.R518X were investigated using genealogical and haplotype analysis (microsatellite markers). In families sharing a common haplotype mutation age and associated prevalence was analyzed using ESTIAGE and DMLE computer software. Results: We identified p.Y111C (170 mutation-carriers) and p.R518X (101 mutation-carriers) as two major causes of LQTS/JLNS in Sweden. LQTS phenotype was revealed to be relatively benign in p.Y111C and p.R518X (annual incidence of life-threatening cardiac events, before therapy 0.05% and 0.04%, respectively). Gender-specific effects of genetic modifiers on phenotypic expression were seen. A founder origin, approximately 600-700 years ago in two northern river valleys was established for p.Y111C and p.R518X, and a high prevalence of LQTS founder descendants suggested. A minimum JLNS prevalence of 1:200 000 in preadolescent Swedish children was revealed. JLNS phenotype was mainly severe, with a cumulative incidence of life-threatening cardiac events of 53% (annual incidence rate before therapy 5%) and four sudden deaths. Possible founder effects regarding four KCNQ1 mutations; p.Y111C (8%), p.R518X (50%), c.572_576del (17%) and p.Q530X (8%) together explained 83% of the JLNS mutation-spectrum in Sweden, consisting of 8 KCNQ1 mutations. Conclusion: The high prevalence of p.Y111C- and p.R518X-related LQTS as well as JLNS revealed in Sweden could be explained by the combination of mild clinical phenotypes in heterozygotes and strong founder effects present during the population development of northern Sweden. Increased knowledge regarding the occurrence of LQTS and JLNS as well as mutation- and/or genotype-specific data constitute prerequisites for possible improvement of patient management.
227

Real-Time Visualization of Construction Equipment Performance / Realtidsvisualisering av materialhantering på bergtäckt

Palomeque, Carlos January 2014 (has links)
This thesis is a proof-of-concept project that aims at modify and reuse existing communication protocols of wireless vehicle to vehicle communication in order to build a prototype of a real time graphical application that runs in an embedded environment. The application is a 2D visualization of the flow of material at a quarry and is built on top of existing communication protocols that enable wireless vehicle to vehicle communication according to the 802.11p standard for intelligent transport solutions. These communication protocols have already been used within the Volvo group in other research rojects, but not in a context of a real-time graphical 2D visualization. The application runs on an ALIX embedded motherboard and combined with the necessary hardware represent one node that makes the communication network. The visualization monitors the position of every active node in the network and the flow of material between material locations and crusher that process the material at the quarry. The visualization is implemented in C/C++ using Qt 4.6.2 Graphics View framework.
228

Testing the Global Banking Glut Hypothesis

Punzi, Maria Teresa, Kauko, Karlo 03 1900 (has links) (PDF)
This paper presents VAR results on the recent economic history of the U.S and focuses on the dependence of U.S. macrofinancial variables on international capital flows. Both gross and net flows are included in the analysis. The results indicate that cross-border funding has affected the build-up in the U.S. housing market irrespective of how these flows are defined and measured. Both the savings glut hypothesis and the banking glut hypothesis are supported by these findings. However, net banking flows appear to explain the higher volatility in the increase in house prices as well as the mortgage loan boom. (authors' abstract) / Series: Department of Economics Working Paper Series
229

Quick and dirty

Buschmann, Anna 18 December 2020 (has links)
Die Studie erforscht institutionalle Arrangements, die auf eine Privatisierung des Agrarlands in der Republik Georgien abzielen, deren Formalisierung der Eigentumsrechte den letzten Schritt der Agrarreformen darstellen, und speziell, wie sich die Durchsetzung des Rechts auf Privateigentum entwickelt hat. Laut Schätzungen ist bisher nur ca. ein Drittel des Landes registriert. Das Ziel der Analyse dient dem Verständnis, wie sich politische Reformen, die eine Privatisierung des Agrarlands beabsichtigen, auf den Landbesitz allgemein und die Agrarproduktion im Besonderen auswirken. Anhand von zwei der führenden landwirtschaftlichen Exportprodukte – Haselnuss und Wein –, verfolgt die Studie methodologisch einen abduktiven Forschungsansatz, der von Triangulation geleitet ist. Die Ergebnisse basieren auf einer Umfrage, Fokusgruppen-Interviews mit Agrarproduzenten sowie Interviews mit Leitern verarbeitender Betriebe, Repräsentanten der Regierung sowie Experten. Die Ergebnisse zeigen einerseits, dass Nutzungs- und später Eigentumsrechte konstant kraft einer ‚property rule’ durchgesetzt wurden, und somit einen Status quo gesichert haben, der besonders die Mitglieder ehemaliger einflussreicher (lokaler) Regierungskreise begünstigt hat; demgegenüber haben die Reformen kontinuierlich Unsicherheit unter der Landbevölkerung erzeugt – indem die Durchsetzung privater Eigentumsrechte von einer ‚property rule’ hin zu einer ‚liability rule’ verändert worden ist –, während die erforderlichen Kosten zur (Wieder-)Erlangung der Besitzansprüche zunehmend den ehemaligen Rechtsinhabern aufgebürdet worden ist. Die Ergebnisse lassen eine potentielle Umverteilung in Form konzentrierten Landbesitzes vermuten, während die Mehrheit der Betriebe künftig auf die Durchsetzung von Landnutzungsrechten vertrauen darf, um ihre Subsistenzwirtschaft fortzuführen. / This study focuses on the institutional change of agricultural land privatization in the Republic of Georgia, where the formalization of private property rights forms the last step of the agrarian land reforms, and specifically how people’s entitle-ment to land has been protected over time. It is estimated that so far only about a third of the land has been registered. The aim of the analysis is to understand how political reforms targeting land privatization have affected land ownership, and to show the effects on agricultural production. By focussing on two leading export products of Georgian agriculture – hazelnut and wine – the study methodologi-cally follows an abductive research strategy led by the principles of triangulation. It is based on survey data, focus groups interviews with agrarian producers as well as interviews with processors, government representatives and experts. The results reveal, on the one hand, that by constantly enforcing use and then owner-ship rights according to a property rule maintained a status-quo which has mainly favored former influential (local) government circles; in contrast, the reforms have persistently generated insecurity to rural neighborhoods – by changing the enforcement of people’s private ownership rights from a property rule to a liabil-ity rule –, while the emerging costs to (re-)claim ownership were increasingly shifted to the former right holders who can hardly raise the required financial means. The results suggest a re-distribution of land in the form of a rising concen-tration of land ownership, while the majority of agricultural producers may rely on the granting of use-rights to proceed with their subsistence farming in the fu-ture.
230

Terminál pro docházkový systém / Attendance System Terminal

Chmelař, Jakub January 2014 (has links)
This thesis deals with electronic attendance systems which are nowadays being widely used to record employee attendance. General problem of attendance tracking is introduced in first part of the thesis along with a conceptual solution of an attendance system terminal. Author then describes a circuitry and a PCB design of a baseboard for a Cubieboard2 minicomputer, a RFID reader and a touchscreen LCD display. After successful testing of said PCB, the terminal has been completed and it was possible to focus on a software solution. Latter part of the thesis is dedicated to a specifics of the Allwinner A20 platform and its support by a GNU/Linux operating system. In following chapter author describes use of a Buildroot software for creating a Linux based binary image for an aforementioned minicomputer. Since an operating system and a peripheral support were successfully tested author could focus on a design and implementation of an attendance software that is described in the final chapter.

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