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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.
201

How to Handle an Internal Venture? : The Effect of Relatedness on the Outcomes of Corporate Venturing

Budryk, Michal, Schmuck, Alice January 2014 (has links)
This paper uses event history analysis to investigate the effects of relatedness on three different outcomes of corporate venturing, identified as retention, termination, and spin-off. For this purpose, relatedness is defined as the degree to which the venture’s activity matches or overlaps with the parent’s activity. Drawing from literature on relational fit, we argue that highly related ventures would be retained, moderately related ones spun off, and unrelated ones would be probable candidates for termination. However, highly related ventures may be likely to pose internal threat to the parent, and consequently be candidates for termination for political reasons as well. This raises the average level of relatedness of terminated ventures above the average of spin-offs. The empirical findings derived from a sample consisting of 78 ventures launched and developed by a number of companies across the Swedish economy give support to our expectations. The highly related ventures were found to be either terminated or retained, moderately related ones were likely to be spun off, and unrelated ones typically faced termination. This supports our hypothesis that relatedness has an impact on how the internal venture is dealt with. We follow with implications for the practice of corporate venturing management.
202

The mechanics of takeoffs in the aerials event of freestyle skiing

Jones, Philip E. January 2012 (has links)
The aerials event of freestyle skiing is a relatively new discipline having only been introduced into the Olympic Games as a medal event in 1994. The purpose of this study was to develop a simulation model for the takeoff phase of aerials, with the intention of learning more about how the requisite linear and angular velocities at takeoff are generated. Experimental data was collected for six triple somersaulting aerial jumps. The jumps were filmed with four high-speed video cameras and a total of 17 points were manually digitised for each camera view of each jump. The digitised coordinates were reconstructed using a three dimensional direct linear transformation (3D-DLT) and processed using a film program written in FORTRAN. The program produced kinematic data for the takeoff phase of the six jumps. A simulation model for takeoff was developed, comprising of a rod (body) and a ski. At the connection between the rod and the ski is a passive torque, governed by the stiffness coefficient K. Experimental values for the height of the centre of mass (CoM), moment of inertia (MoI), initial linear velocity (VG) and initial angular velocity (ωpg) were used as model inputs. A combined drag and air resistance coefficient (D) was varied with K to match the experimental VG and ωpg at takeoff, resulting in an average difference of -0.07% for VG, and -16.10% for ωpg. A straight body simulation was run, eliminating the effect of joint angle changes on CoM height and MoI, it was found that a straight body matches the experimental data just as well as a simulation using joint angles. This result suggests that joint angles changes play a different role, other than to generate angular and linear velocity. Further alterations were made to the model parameters; K was varied, which increased the angle of the CoM behind the normal to the skis (ψ) as K increased. Initial angular velocity was varied with results suggesting that a forwards leaning motion at the start of the kicker generated a larger angular velocity at takeoff. An additional ankle torque was implemented for the final 0.1s of takeoff, this increased ωpg and reduced the difference to just -3.01%. Conclusions were drawn that the passive torque of the skis and an additional ankle torque prior to takeoff play a large role in governing takeoff conditions.
203

Prototype campaign assessment of disturbance-induced tree loss effects on surface properties for atmospheric modeling

Villegas, Juan Camilo, Law, Darin J., Stark, Scott C., Minor, David M., Breshears, David D., Saleska, Scott R., Swann, Abigail L. S., Garcia, Elizabeth S., Bella, Elizabeth M., Morton, John M., Cobb, Neil S., Barron-Gafford, Greg A., Litvak, Marcy E., Kolb, Thomas E. 03 1900 (has links)
Changes in large-scale vegetation structure triggered by processes such as deforestation, wildfires, and tree die-off alter surface structure, energy balance, and associated albedo-all critical for land surface models. Characterizing these properties usually requires long-term data, precluding characterization of rapid vegetation changes such as those increasingly occurring in the Anthropocene. Consequently, the characterization of rapid events is limited and only possible in a few specific areas. We use a campaign approach to characterize surface properties associated with vegetation structure. In our approach, a profiling LiDAR and hemispherical image analyses quantify vegetation structure and a portable mast instrumented with a net radiometer, wind-humidity-temperature stations in a vertical profile, and soil temperature-heat flux characterize surface properties. We illustrate the application of our approach in two forest types (boreal and semiarid) with disturbance-induced tree loss. Our prototype characterizes major structural changes associated with tree loss, changes in vertical wind profiles, surface roughness energy balance partitioning, a proxy for NDVI (Normalized Differential Vegetation Index), and albedo. Multi-day albedo estimates, which differed between control and disturbed areas, were similar to tower-based multiyear characterizations, highlighting the utility and potential of the campaign approach. Our prototype provides general characterization of surface and boundary-layer properties relevant for land surface models, strategically enabling preliminary characterization of rapid vegetation disturbance events.
204

Variation in Immune Response Among Native and Invading Genotypes of Yellow Starthistle (Centaurea solstitialis)

Kaczowka, Angela M., Kaczowka, Angela M. January 2017 (has links)
Invasive plants may leave enemies behind when they colonize a new habitat, allowing selection to favor increased investment in growth and/or reproduction over defensive traits. Previous studies have identified reduced diversity of potential bacterial pathogens and evolutionary increases in growth and reproduction in invading populations of yellow starthistle (Centaurea solstitialis). This study leverages a recently developed high-throughput assay of immune function to test for evidence of a trade-off between increased growth and defense against bacterial pathogens in yellow starthistle's invasion of California (USA). Seven bacterial strains were cultured from infected leaf tissue in the native range. Healthy leaf tissue from five native European collections and six invading collections were exposed to these native bacterial strains. A standardized assay of peroxidase activity was used measure the oxidative burst immune response to pathogen recognition by the leaf. Immune responses were compared to plant growth within and between ranges to assess evidence for a trade-off. Plant genotypes from the native range demonstrated a higher immune response to bacterial strains than did invading genotypes, consistent with a trade-off with plant growth across regions. The same trade-off was also apparent across genotypes from the native range, but not across genotypes from the invaded range. Our results provide evidence that increased growth in a highly invasive plant species may come at a cost to immune function, consistent with the hypothesis that escape from enemies can provide opportunities for shifts in resource allocation that favor the proliferation of non-native species.
205

Fabrication and testing of 4.2m off-axis aspheric primary mirror of Daniel K. Inouye Solar Telescope

Oh, Chang Jin, Lowman, Andrew E., Smith, Greg A., Su, Peng, Huang, Run, Su, Tianquan, Kim, Daewook, Zhao, Chunyu, Zhou, Ping, Burge, James H. 22 July 2016 (has links)
Daniel K. Inouye Solar Telescope (formerly known as Advanced Technology Solar Telescope) will be the largest optical solar telescope ever built to provide greatly improved image, spatial and spectral resolution and to collect sufficient light flux of Sun. To meet the requirements of the telescope the design adopted a 4m aperture off-axis parabolic primary mirror with challenging specifications of the surface quality including the surface figure, irregularity and BRDF. The mirror has been completed at the College of Optical Sciences in the University of Arizona and it meets every aspect of requirement with margin. In fact this mirror may be the smoothest large mirror ever made. This paper presents the detail fabrication process and metrology applied to the mirror from the grinding to finish, that include extremely stable hydraulic support, IR and Visible deflectometry, Interferometry and Computer Controlled fabrication process developed at the University of Arizona.
206

Power Consumption Models for Streaming on Mobile Terminals with On-Off Characteristics

Godavarthi, Nandini Chowdary January 2016 (has links)
The usage of smartphones has been increasing with surprising speed. These smartphones are popular for delivery of video content. The main drawbacks of these smartphones are battery life and video freezing. Despite, while streaming a video it consumes large of amount of power affecting QoE. So, in this case we considered streaming a video from server to mobile client involving ONOFF characteristics. While streaming, there exists some transition delay while switching the power states and the effect of these transition delays might affect instantaneous power consumption of the smartphone. Henceforth, this thesis aims to determine the effect on instantaneous power consumption from distributed state durations and transitions in exponential fluid flow model, for a streamed video. Power measurements along with ON and OFF times were measured with the help of a benchmark tool, Monsoon Power Monitor tool. VLQoE tool, a video streaming tool was used to present a two state model based on the inter-picture time, for the HTTP-based video streaming. Experiments were executed in a closed enclosure setup using a black-box to avoid external obstacles that might possibly affect the power consumption metrics. Considering these measurements, the effect on instantaneous power consumption stemming from the exponentially distributed state durations and transitions in the corresponding fluid flow model can be determined and modelled.
207

A Study to Establish Some Guiding Principles for Public School Administrators to Use in Off-campus Student-teaching Programs

Latham, James L. 05 1900 (has links)
This study is directed to the establishment of some principles to serve as guides for public school administrators and college authorities in conducting off-campus student-teaching programs.
208

The Raddled Vessel

Grieff, Stacey 11 March 2013 (has links)
The wearing effects of being overworked and in somewhat poor health are reflected in my paintings, ceramic work, and mixed media pieces. I use old and dilapidated materials such as window frames, instrument cases, and wood to symbolically address my physical and emotional states. I reuse items from the past that show a sense of fatigue, tattered edges, and deterioration. Like these objects I felt run down, old, and at times, useless. However, I am comforted by the idea that old objects can, with some care, regain new life. I have discovered I seek my own rejuvenation through my creativity. As a means of releasing anger and frustration toward my fading health, I create assemblages of wilted flowers, encaustic hourglass forms, and mixed media teapots. I also create clay vessels that appear to be deteriorating and encapsulate objects in encaustic medium. Items that belonged to my relatives serve as a metaphor for my genetic illnesses. Searching for answers, living in the present, and maintaining hope are things I carry with me on my artistic journey to find a sense of self worth and to overcome disease.
209

Daňová soustava a dohody o zamezení dvojího zdanění / The tax system and agreements on the avoidance of double taxation

Kohoutová, Petra January 2013 (has links)
1 Abstract: The tax system and agreements on the avoidance of double taxation This diploma thesis "The tax system and agreements on the avoidance of double taxation" is focused on practical issues in the field of using international corporate structure in order to decrease the tax liability applicable on entrepreneurs. The diploma thesis includes the basic description of the legal rules applicable in the Czech Republic, such as acts and also international treaties. In the field of EU law, the diploma thesis described briefly EU directives based on which it is possible to transfer dividends, interest and royalties between mother and daughter companies without withholding tax payable in the Czech Republic. International treaties described in this diploma thesis were double taxation avoidance treaties between the Czech Republic and Cyprus and between Cyprus and Seychelles. First part of the diploma thesis is describing legal regulation of income taxes applicable in the Czech Republic. It is aimed mainly on interests, dividends and royalties. The first part of the diploma thesis is of theoretical nature which gives basics for the second and third part which practically analyze possibilities to decrease tax burdens of entrepreneurs. Second part of the diploma thesis brings analysis of individual model situations...
210

Ion tempeture measurements in the scrape-off layer of the Tore Supra Tokamak / Mesure de la température ionique dans le plasma périphérique du Tokamak Tore-Supra

Kocan, Martin 06 October 2009 (has links)
La thèse décrit les mesures de températures ioniques (Ti) dans la Scrape-Off-Layer (SOL) – un paramètre important cependant rarement mesuré – à l'aide d'une sonde Analyseur à Retard de Champ (RFA) installée sur le Tokamak Tore Supra. La thèse s'organise en 4 chapitres. Dans le premier sont brièvement rappelés les enjeux de la fusion nucléaire, la géométrie des limiteurs et la physique la SOL, le principe des sondes de Langmuir, etc. Sont aussi adressés les différents diagnostics dédiés aux mesures de Ti dans la SOL, utilisés dans le passé. Le second chapitre est consacré au RFA. Le principe de l'analyseur, les détails techniques et opérationnels sur Tore Supra ainsi que les effets instrumentaux sur les mesures y sont abordés. Il est conclut que l'influence instrumentale sur les mesures RFA de Ti sont relativement faibles. Dans le troisième chapitre, les mesures systématiques de Ti (ainsi que d'autres paramètres) dans la SOL de Tore Supra sont présentées. Il est montré que le rapport Ti / Te > 1 (Te étant la température électronique) dans la SOL, mais aussi dans le plasma confiné ; et que ce rapport augmente avec le rayon plasma. Un autre résultat important est que Ti dans la SOL change significativement, suivant étroitement les paramètres centraux, alors que Te dans la SOL n'évolue presque pas. Dans le dernier chapitre est présenté le statut actuel de trois projets en cours visant à valider indépendamment la mesure de Ti dans la SOL de Tore Supra : le développement d'une tête de sonde à tunnel segmenté permettant une mesure des fluctuations de Ti dans la SOL ; la mesure de Ti au bord des plasmas du Tokamak Joint European Torus (JET) ; et la comparaison des mesures de RFA avec les mesures de spectroscopie d'échange de charge et recombinaison (CXRS) sur Tore Supra. / The thesis describes measurements of the scrape-off layer (SOL) ion temperature Ti – an important but yet rarely measured parameter – with a retarding field analyzer (RFA) probe in the limiter tokamak Tore Supra. The thesis is organized in four chapters. In the first chapter, some well known facts about nuclear fusion, limiter SOL, Langmuir probes, etc. are briefly recalled. Various diagnostics for SOL Ti measurements developed in the past are addressed as well. The second chapter is dedicated to the RFA. The principle of the RFA, technical details and operation of the Tore Supra RFA, and the influence of instrumental effects on RFA measurements are addressed. It is concluded that the influence of instrumental effects on RFA Ti measurements is relatively small. In the third chapter, the systematic measurements of Ti (as well as other parameters) in the Tore Supra SOL are presented. It is shown that Ti / Te >1 (with Te being the electron temperature) in the SOL but also in the confined plasma, and increases with radius. Also important result is that while SOL Ti changes significantly, following the core properties rather closely, SOL Te hardly changes at all. In the final chapter the present status of three ongoing projects aimed at the independent validation of SOL Ti measurements in Tore Supra is presented: the development of the segmented tunnel probe for fast SOL Ti measurements, the measurement of edge ion temperature in Joint European Torus (JET) tokamak, and the comparison of RFA with charge exchange recombination spectroscopy in Tore Supra.

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