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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.
21

Behavioural evidence for magnetic orientation in rodents / Behavioural evidence for magnetic orientation in rodents

OLIVERIUSOVÁ, Ludmila January 2015 (has links)
Magnetoreception in rodents was studied in this Ph.D. thesis. Behavioural evidence for compass magnetic orientation was found in two subterranean African rodents: the social giant mole-rat (Fukomys mechowii) and solitary silvery mole-rat (Heliophobius argenteocinereus) and epigeic rodent bank vole (Clethrionomys glareolus). The study is also focused on the role of magnetic orientation in solving the orientation task in Morris water maze in bank vole.
22

The role and contribution of the Chief Technology Officer

van der Hoven, Christopher January 2011 (has links)
The Role and Contribution of the Chief Technology OfficerThe role of the Chief Technology Officer (CTO) came about because of new organisational demands on technology leaders in the 1980s. The initial research objective of this dissertation was to provide a clear scope of activities (a remit) for the CTO role. However, the analysis did not support a generic description for the role. Therefore, the approach taken explores CTO perspectives on technology management priorities when the technology context changes. There is limited literature on the role and contribution of the CTO per se. The resulting gap in the knowledge about the role is amplified by a wide variety of research methods and academic perspectives. From a theoretical point of view, the existing research tends to focus in isolation on the work being done, the working context or the worker (i.e. the CTO). There are studies that consider how the working context is changing, and studies that consider the work of the CTO, for example, the technology management priorities. There are still other studies that consider the attributes of the CTO. In this dissertation, these three perspectives - the working context, the work and the worker - are investigated in an integrated way using a data collection technique called 'personal role mapping' that is based on cognitive mapping. The 'personal role mapping' approach has been developed as part of this work. The evidence collected and analysed shows that the role of the CTO is highly idiosyncratic. This is because the CTO role changes as the organisation adapts in order to compete. Also, the role differs from one industry to another and between organisations within the same industry. To help deal with these variations, a CTO/Context Framework has been derived for use in conjunction with 'technology transition points'. The CTO/Context Framework has 20 sub-elements that support 6 primary elements including, 'technology management infrastructure', 'technology entry/exit points', 'technology business case & funding', 'operational improvement', 'people management' and 'technology business model & strategy'. The CTO can review each element with related sub-elements in anticipation or at the point of a 'technology transition'. This model for the CTO role is proposed as an alternative to a generic 'job description' (remit) for the CTO role. It is intended to be used as a platform for planning and decision-making. Together, the framework and the research approach for mapping an individual's role are offered as a unique contribution to knowledge.
23

Lokalizátor interferencí pro kmitočtová pásma EGSM a UMTS / Interference locator for EGSM and UMTS frequency bands

Predajňa, Martin January 2011 (has links)
Diploma thesis describes direction finding principles for passive localization of emitting source. Direction finding system with one rotating antenna was chosen with triangulation calculation of emitter position. Input parameters are position of measurement point and direction of maximum signal receiving level. A suitable digital compass module and GPS receiver module for this measurement was chosen. For this purpose was created a graphic user interface, which allow user to communicate with external devices and control spectrum analyzer. Results of measurements are displayed at map, together with area of possible positions of transmitter. Receiving Yagi antenna is placed on rotator and whole system is placed on roof of car. Whole system was construct and results of measurement are discuss here.
24

An investigation into business people’s spiritual value compasses

Mayet, Khadija Mahommed Hosain 23 February 2013 (has links)
The purpose of this study, which primarily focuses on spiritual values, was to develop a measurement for nine spiritual anchors – perfection, compassion, passion, inspiration, investigation, dedication, appreciation, determination and cooperation – as proposed by Karakas (2010). Through the development of such a measurement, the concept and construct of spiritual anchors was investigated and definitions were refined.After reviewing the literature on workplace spirituality and personal values, a Spiritual Value Compass Inventory was developed. The 350 responses received after distributing the inventory to a sample of South African MBA students was analysed using exploratory and confirmatory factor analysis. The findings from these analyses yielded a spiritual value compass model.The spiritual value compass model outlines the spiritual anchors held by this diverse group of businesspeople, which was shaped as “passion”, “compassion”, “investigation” and “determination”. These anchors bear relevance to Karakas’ (2010) original framework for spiritual anchors, however, they have been refined through empirical evidence.The Spiritual Value Compass Inventory and the Spiritual Value Compass model provide professionals and managers with tools to understanding their spirituality and value compasses, and could form part of an important step towards preparing these business leaders to manage and create a workforce that is motivated to perform optimally. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted
25

Diagnostika Thomsonovým rozptylem na tokamaku COMPASS / Thomson Scattering Diagnostic on COMPASS Tokamak

Aftanas, Milan January 2015 (has links)
Thorough study of plasma behaviour in magnetically confined fusion devices is of great importance in recent research. Diagnostics capable to reliably provide important parameters of the hot plasma are key tool in the effort to control fusion energy on Earth. Thomson Scattering diagnostic has a credit of being a complex design diagnostic with reliable measurement of electron temperature and density profiles. The main subjects of this thesis are design of the Thomson Scattering system for the COMPASS tokamak, analysis of output data errors and exploitation of the data to study plasma behaviour. Besides this work, the author has been involved in the design of Thomson Scattering systems for the ITER tokamak and this design is presented here as well. Powered by TCPDF (www.tcpdf.org)
26

Computational Chemistry and Molecular Modeling of Polyphosphazenes for Biomedical Applications

Kroger, Jessica 05 October 2012 (has links)
No description available.
27

Behavioral Investigation of the Light-Dependent Magnetoreception Mechanism of Drosophila melanogaster

Dommer, David H. 11 August 2008 (has links)
Use of a magnetic compass has been demonstrated in all major classes of vertebrates as well as several classes of invertebrates, and is proposed to involve a photo-induced radical pair mechanism (RPM). My dissertation research consisted of characterizing a magnetic compass in a model species, Drosophila melanogaster. Preliminary experiments were carried out with adult flies, however, due to the behavioral complexity of adult responses a new behavioral assay of magnetic compass orientation was developed using larval Drosophila that elicits a robust magnetic compass response in a trained magnetic direction. This manuscript describes experiments that were conducted showing that larval magnetic compass orientation: 1) demonstrates a complex 3-dimensional pattern of response consistent with a RPM; 2) is consistent with a receptor mechanism that utilizes short- and long-wavelength antagonistic photopigments, proposed to explain wavelength dependent effects in vertebrates (e.g. amphibians and birds); and 3) produces axially symmetrical patterns of response with respect to the geomagnetic field. Additionally, tests of adult Drosophila under low and high intensities of monochromatic long wavelength light revealed a similar behavioral response to varying intensities of monochromatic light as previously reported in migratory birds (E. rubecula). These findings indicate that the magnetic compass of larval Drosophila shares a common functional architecture and similar biophysical mechanism with that of at least some vertebrates (e.g. amphibians and possibly birds), suggesting that the magnetic compass of modern vertebrates may have evolved once in a common ancestor of these three lineages over 450 million years ago. Furthermore, findings indicating a spontaneous preference for magnetic directions in D. melanogaster larvae suggest that a light-dependent magnetoreception mechanism is more widespread in insects than was previously suspected. The development of a behavioral assay to study the light-dependent magnetic compass in an organism with a simple nervous system, a limited behavioral repertoire, and with the possibility of using the full power of modern molecular and genetic techniques holds considerable promise to increase our understanding of the biophysical mechanism(s) and neurophysiological structures underlying magnetic orientation in terrestrial animals. / Ph. D.
28

Tilt-Compensated Magnetic Field Sensor

Bingaman, Adam Neal 22 June 2010 (has links)
Motion and tilt have long hindered the accuracy, reliability, and response of magnetic detection systems. Perturbations in the magnetic field reading resulting from motion cause degradation of the output signal, compromising the performance and reliability of the magnetometer system. The purpose of this document is to describe the development, construction, and testing of a tilt-stabilized three-axis magnetic field sensor. The sensor is implemented as a three-axis general-purpose magnetic field sensor, with the additional capability of being implemented as a compass. Design and construction of system hardware is discussed, along with software development and implementation. Finite impulse response filters are designed and implemented in hardware to filter the acquired magnetic signals. Various designs of median filters are simulated and tested for smoothing inclination signal irregularities and noise. Trigonometric conversions necessary for tilt-compensation are calculated in software using traditional methods, as well as the Coordinate Rotation Digital Computer (CORDIC) algorithm. Both calculation methods are compared for execution time and efficiency. Successful incorporation of all design aspects leads to detection and output of stable earth magnetic fields, sinusoidal signals, and aperiodic signatures while the magnetometer system is subject to significant tilt motion. Optimized system execution time leads to a maximum detectable signal bandwidth of 410 Hz. Integration of azimuth angle calculation is incorporated and is successfully tested with minimal error, allowing the system to be used as a compass. Results of the compensated system tests are compared to non-compensated results to display system performance, including tilt-compensation effectiveness, noise attenuation, and operational speed. / Master of Science
29

Measurement of Hadron Multiplicities in Deep Inelastic Scattering and Extraction of Quark Fragmentation Functions / Mesure de multiplicités des Hadrons en Diffusion Profondément inélastique et Extraction de Fonctions de Fragmentation des Quark

Curiel Garcia, Quiela Marina 11 December 2014 (has links)
One of the goals of the COMPASS experience is the study of the nucleon spin structure. Data were taken from a polarized muon beam (160 GeV/c) scattering off a polarized target (6LiD or NH3). In this context, the need of a precise knowledge of quark Fragmentation Functions (final-state hadronisation of quarks q into hadrons h, FFs) was raised. The FFs can be extracted from hadron multiplicities produced in Semi-Inclusive Deep Inelastic Scattering (SIDIS). This thesis presents the measurement of charged hadrons (pions and kaons) multiplicities from SIDIS data collected in 2006. The data cover a large kinematical range: Q2>1 (GeV/c)2, y є [0.1,0.9], x є [0.004,0.7] and W є [5,17] GeV. These multiplicities provide an important input for global QCD analyses of world data at NLO, aiming at the FFs determination. / L'un des objectifs de l'expérience COMPASS est l'étude de la structure du nucléon de spin. Les données ont été prises à partir d'un faisceau de muons polarisée (160 GeV/c) diffuse sur une cible polarisée (6LiD ou NH3). Dans ce contexte, la nécessité d'une connaissance précise des fonctions de fragmentation des quarks (état final du hadronisation de quarks q en hadrons h, FFs) a été soulevée. Le FFs peuvent être extraites de multiplicités de hadrons produits en Semi-Inclusive diffusion profondément inélastique (SIDIS). Cette thèse présente la mesure de la multiplicité de hadrons charge (pions et kaons) à partir de données SIDIS collectées en 2006. Les données couvrent un large domaine cinématique : Q2>1 (GeV/c)2, y є [0.1,0.9], x є [0.004,0.7] and W є [5,17] GeV. Ces multiplicités fournissent un apport important pour l'analyse des données mondiales au 2ème ordre de QCD, visant la détermination de FFs.
30

Nízkoteplotní polarizovaný terč pro studium spinové struktury nuklonů v experimentu COMPASS / Low temperature polarized target for spin structure studies of nucleons at COMPASS

Pešek, Michael January 2014 (has links)
Title: Low temperature polarized target for spin structure studies of nucleons at COMPASS Author: Bc. Michael Pešek Department: Department of low temperature physics Supervisor of the master thesis: prof. Ing. Miroslav Finger, DrSc. Abstract: In presented thesis we describe concept of Deep Inelastic Scattering of leptons on nucleons in context of nucleon spin structure studies. Both polarized and unpolarized cases are discussed and concept of Transverse Momentum Dependent Parton Distribution Functions (TMD PDF) is introduced. The possibility of TMDs measurement using Semi-inclusive DIS (SIDIS) is described along with related results from COMPASS experiment. The future Drell-Yan programme at COMPASS is briefly mentioned and its importance is presented on the universality test i.e. change of sign of T-odd TMDs when measured in Drell-Yan and SIDIS. The importance of Polarized Target (PT) for spin structure studies is highlighted and principles of Dynamic Nuclear Polarization (DNP) are given using both Solid effect and spin temperature concept. COMPASS experiment is described in many details with accent given to PT. Finally the thermal equilibrium (TE) calibration procedure is described and carried out for 2010 and 2011 physics runs at COMPASS. The average polarization measurement results from 2010 and 2011 are...

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