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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.
131

Impression management strategies: the effects of attribution and presentantion order

Moreira, Rafael de Lacerda 30 May 2018 (has links)
Submitted by Rafael de Lacerda Moreira (rafaeldelacerdamoreira@gmail.com) on 2018-07-21T22:14:47Z No. of bitstreams: 1 Versão Final - Tese Rafael .pdf: 1250031 bytes, checksum: 3abf55725921846132052a1324efd6fa (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2018-07-26T16:40:59Z (GMT) No. of bitstreams: 1 Versão Final - Tese Rafael .pdf: 1250031 bytes, checksum: 3abf55725921846132052a1324efd6fa (MD5) / Made available in DSpace on 2018-07-27T19:56:45Z (GMT). No. of bitstreams: 1 Versão Final - Tese Rafael .pdf: 1250031 bytes, checksum: 3abf55725921846132052a1324efd6fa (MD5) Previous issue date: 2018-05-30 / Purpose - This research analyzes how corporate narrative disclosure can be manipulated by preparers of accounting information to create a favorable impression of the company through an examination of two different impression-management (IM) strategies: (i) attribution, and (ii) ordering or physical location of information. Design/Methodology - We conducted a 4×2 mixed-design experiment to examine the impact of attribution and optimal direction of information order on earnings forecast and the impression created about the company. Findings - Results show that the favorable report read first, without attribution, positively affects the investor, and that the favorable information read first, with attribution, undermines the positive effect. Conversely, presenting unfavorable information, with attribution, first, minimizes the impact of this information. Our findings confirm self-promoter’s paradox idea. We also tested a sandwich and an interspersed ordering (control) group; these had the worst results. In a mediation analysis, we found that perceived impression about the company mediates the relationship between information and decision-making. In addition, our results show a significant difference in decision-making influenced by users’ characteristics. In a robustness test, we tested credibility of information as an alternative explanation, finding that credibility was not an alternative explanation for investors’ decision found in the experiment. We conclude by offering suggestions for further study of IM. Originality – To our knowledge, this is the first study that analyses the effects of both attribution and ordering strategies at the same time. Literature has addressed both strategies separately but has not discussed their interactive effect. This research addresses this gap.
132

Diagnostics and characterization of beam halo at the KEK Accelerator Test Facility / Mesures et caractérisation du halo du faisceau de l'accélérateur ATF au KEK

Yang, Renjun 05 October 2018 (has links)
Aux futurs collisionneurs linéaires et circulaires, la présence d’un halo autour du faisceau est susceptible de fortement limiter les performances, et peut également activer, voire endommager, les composants de l’accélérateur. Le halo doit par conséquent est contrôlé par un système de collimateurs efficace. Pour évaluer l’impact sur les expériences de physique des particules ainsi que les efficacités de collimation, une bonne compréhension des mécanismes physiques générateurs de halo est essentielle, pour par exemple prédire les distributions de probabilité de manière fiable. Pour ce faire, une investigation systématique ont été menée à l’Accelerator Test Facility (ATF) du KEK dans le cadre de cette thèse, d’abord à travers une analyse théorique des principales sources de halo dans ATF, puis moyennant le développement et l’implémentation de diagnostiques dédiés aux mesures du halo, dont les résultat sont ensuite présentés et comparés aux prédictions théoriques. Le halo produit par la diffusion des particules du faisceau sur les noyaux des molécules du gaz résiduel dans la chambre à vide (« Beam Gas Scattering » - BGS) est d’abord estimé analytiquement, avec certaines approximations, puis moyennant une simulation Monte-Carlo. Un nombre considérable de particules de halo BGS est prédit, ainsi qu’une dépendance dans la pression de gaz résiduel. Pour étudier la possible formation d’un halo par le mécanisme de diffusion intra-paquet à grand angle dit de « Touschek » en présence d’une dispersion optique résiduelle, le taux de cette diffusion a été estimé en fonction de plusieurs paramètres faisceau pertinents. Une simulation Monte-Carlo de la diffusion intra-faisceau à petit angle (IBS) et de « Touschek » est aussi en cours de développement. Pour tester les prédictions théoriques, les performances d’un détecteur de halo déjà existant basé sur un capteur diamant ont été améliorées moyennant une technique de repondération qui a permis d’en augmenter la gamme dynamique jusqu’à 10⁵. Afin de disposer d’un instrument complémentaire pour mesurer le halo, un moniteur YAG/OTR a aussi été conçu, construit et installé dans la ligne d’extraction d’ATF. Il a pu être montré que la gamme dynamique et la résolution de ce moniteur YAGOTR sont, respectivement, autour de 10⁵ et inférieure à 10 μm. Grâce aux diagnostiques développés pour mesurer le halo du faisceau d’ATF, les distributions transverses et en énergie ont pu être étudiées. L’accord satisfaisant obtenu entre les prédictions théoriques et les mesures, ainsi qu’une dépendance importante dans la pression de gaz résiduel, ont permis de montrer que la distribution verticale du halo est dominée par le mécanisme BGS. Par contre, la distribution horizontale est bien supérieure aux prédictions BGS, et est par ailleurs asymétrique. L’asymétrie observée peut être en partie reliée à la qualité du champ de l’élément pulsé servant à l’extraction du faisceau d’ATF, ainsi qu’à certaines aberrations dans le transport optique. La distribution de probabilité du halo en fonction de l’énergie a par ailleurs pu être mesurée, grâce à une technique nouvelle d’ajustement de la dispersion optique dans le plan vertical, et a été trouvée compatible qualitativement avec le mécanisme de diffusion « Touschek ». Un scénario plausible de génération du halo dans le plan horizontal a ainsi pu être suggéré. / At future linear and circular colliders, beam halo can strongly limit machine performances, cause as well component damage and activation, and should, therefore, be controlled by an efficient collimation system. To evaluate the impact on particle physics experiments and collimation efficiencies, a clear understanding of beam halo formation mechanisms is essential, e.g., to predict halo distribution reliably. For this purpose, systematic investigations have been carried out at the Accelerator Test Facility (ATF) of KEK. In this dissertation, the theoretical analysis of the primary halo sources at ATF and the development of dedicated halo diagnostics are presented. Measurements of beam halo at ATF are also described and compared with the theoretical predictions. Beam halo arising from Beam-Gas Scattering (BGS) in the damping ring was firstly estimated through analytical approximations and a Monte Carlo simulation. A considerable amount of halo particles generated by BGS and the corresponding vacuum dependence have been predicted. To explore the probability of beam halo formation from Touschek scattering in the presence of dispersion, the Touschek scattering rate was estimated with respect to relevant beam parameters. Furthermore, a Monte Carlo simulation of Intra-Beam Scattering (IBS) and Touschek scattering is under development. To probe the theoretical predictions, the performance of an already existing diamond sensor detector was optimized via a data rescaling technique to increase the dynamic range to 1×10⁵. For a complementary diagnostics of beam halo, a YAG/OTR monitor was also designed and installed in the extraction section of ATF2. The dynamic range and resolution of the YAG/OTR monitor have been shown to be around 1×10⁵ and less than 10 μm, respectively. Thanks to the halo monitors developed at ATF2, the transverse halo and momentum tail have been studied. Satisfactory agreement between numerical predictions and measurements as well as a significant vacuum dependence indicate that the BGS process dominates the vertical halo. On the other hand, the horizontal halo appeared to be higher than the prediction from BGS, and moreover asymmetric. The observed asymmetry was shown to be related to the quality of the extraction kicker field and optical aberration. Finally, the momentum tail was for the first time observed by implementing a novel scheme of vertical dispersion adjustment and was found to be qualitatively consistent with the presence of Touschek scattering. A possible scenario for horizontal beam halo formation from Touschek scattering was also suggested.
133

"Sistemas fracamente ligados de três corpos: moléculas e núcleos exóticos leves"

Yamashita, Marcelo Takeshi 10 December 2004 (has links)
Um potencial de dois corpos do tipo delta-Dirac foi utilizado para descrever sistemas fracamente ligados de três corpos. A trajetória completa dos estados Efimov em função da energia ligação de dois corpos foi calculada para o caso de três bosons idênticos: se o subsistema de dois corpos é ligado, conforme a razão entre a energia de ligação de dois e três corpos aumenta, o estado excitado desaparece e um estado virtual correspondente aparece quando a energia do estado fundamental atinge o limiar dado por 6.9hbar^2/(ma^2) (a - comprimento de espalhamento, m - massa do bóson). Quando o subsistema de dois corpos é virtual, o aumento da razão entre as energias faz com que o estado excitado se transforme em uma ressonância quando a energia do estado fundamental é 1.1hbar^2/(ma^2). Neste último caso as condições para a formação de moléculas triatômicas no interior de condensados é favorecida, pois a competição com dímeros fracamente ligados está ausente. A energia de ligação de trímeros com momento angular total nulo em condensados atômicos foi estimada através da correlação desta com o coeficiente de recombinação e com a energia do dímero, ambos conhecidos experimentalmente em alguns casos. Os tamanhos de moléculas fracamente ligadas (^4He_2$-X; Xequiv^4He, ^6Li, ^7Li e ^{23}Na) e de núcleos exóticos leves (^6He, ^{11}Li, ^{14}Be e ^{20}C) também foram calculados juntamente com um estudo sistemático do comportamento dos raios quadráticos médios conforme a interação dos subsistemas de dois corpos é variada. Neste último caso a classificação de um sistema de três corpos (tipo AAB) foi completada denominando de Samba a configuração formada por dois subsistemas de dois corpos ligados e um virtual. As equações subtraídas para os estados ligados de quatro bosons também foram deduzidas.
134

Florida Red Tides: Public Perceptions of Risk

Allen, Sara E 09 November 2007 (has links)
This research integrates the theoretical implications of risk perception, the social amplification of risk, and the role of place-specific contexts, in order to explore the various perceptions surrounding Florida red tides. Florida red tides are a naturally-occurring event, yet most scientists agree that they are increasing in frequency, duration, and severity. This has profound implication for public health, the local economy, and the biological community. While many of the negative impacts are not easily controllable at this time, some of the secondary impacts can be mitigated through individuals' responses. Unfortunately, public perceptions and consequent reactions to red tides have not been investigated. This research uses questionnaire surveys, semi-structured interviews, and newspaper content analysis to explore the various perceptions of risk surrounding red tides. Surveys and interviews were conducted along two Florida west coast beaches, Fort De Soto Park and Siesta Key. Results indicate that the underlying foundations of the social amplification of risk framework are applicable to understanding how individuals form perceptions of risk relative to red tide events. There are key differences between the spatial locations of individuals and corresponding perceptions, indicating that place-specific contexts are essential to understanding how individuals receive and interpret risk information. The results also suggest that individuals may be lacking efficient and up-to-date information about red tides and their impacts due to inconsistent public outreach. Overall, particular social and spatial factors appear to be more influential as to whether individuals amplify or attenuate the risks associated with red tides.
135

DEVELOPMENT OF AN EMPLOYEE GREEN BEHAVIOR DESCRIPTIVE NORMS SCALE

McConnaughy, Jacqueline Christine 01 June 2014 (has links)
With a growing interest in sustainability, organizations and researchers have begun to examine pro-environmental behaviors in the workplace (i.e. employee green behaviors). However, general understanding of employee green behaviors is currently limited due to a lack of measurement tools. In this study, a new scale was developed to measure employee green behavior descriptive norms, which are a source of influence on employee green behaviors that develops from observing others’ behaviors. Initial items and expected scale structure for the Employee Green Behavior Descriptive Norms Scale were developed based on the Green Five Taxonomy of employee green behaviors. Items were refined through pilot test data and a retranslation task. Data on the refined scale, the Ethical Leadership Questionnaire, and a Work-Family Culture Scale were used to test scale structure and gather evidence of construct validity. Study results supported the expected scale structure and construct validity of the newly developed scale. A multi-item, validated scale contributes to organizational assessment of employee green behavior descriptive norms and contributes to the scientific literature on employee green behaviors.
136

Chemical Abundance Analysis of Population II Stars : The Summary Includes a Background in General Astronomy

Jonsell, Karin January 2005 (has links)
<p>We are made of stardust in the sense that most atomic nuclei around us have been formed by stars. Stars synthesise new elements and expel them to the interstellar medium, from which later new generations of stars are born. We can map this chemical evolution by analysing the atmospheric contents of old Galactic halo stars. I have done two such investigations. A vigourous debate is going on whether the oxygen-to-iron ratio varies strongly with the general metal-content of halo stars. In my first study, I made an abundance analysis of 43 halo stars, and found no support for such a variation. I have also found that there probably is a cosmic spread in the abundances of oxygen, magnesium, silicon, and calcium relative to iron for halo stars. This may be an indication that the halo was built up by subsystems with differences in the star formation rate. In my second study, I performed a thorough abundance analysis of the star HE0338-3945, which is strangely overabundant in both r- and s-elements. Several other stars have been found with abundance patterns curiously similar to this star, and I define new criteria for the class r+s stars. The abundance similarities among the r+s stars suggest a common formation scenario. However, as the s-elements usually are considered to be produced in binary systems of low mass, and r-elements in supernovae of Type II, this scenario is not obvious. In the article I discuss seven hypotheses, and several of them are dismissed.</p>
137

A methodology for characterizing and introducing MOSFET imperfections in analog top-down synthesis and bottom-up validation

Vancaillie, Laurent 31 August 2005 (has links)
State-of-the art electronic systems include ever more features and gather mixed-signal subsystems, possibly from different physical domains. At the same time, cost and development time are reduced; stressing the need for an efficient design flow for fast and reliable design. The present thesis contributes to the construction of an improved design flow supported by mixed-signal hardware description languages (HDL-AMS). In a hierarchical view, the electronic systems are recursively divided into subsystems, down to basic cells and transistor level. The typical design flow results of a top-down synthesis, from the system specifications to the physical realizations, and of a bottom-up validation, from the test of the basic cells up to the test of the system. To improve the link between the technological level and the basic cells, we develop a measurement-based analog ID card which aims to optimize the analog performance and the reliability at high temperature by enabling the choice of optimal process (bulk vs. partially-depleted silicon-on-insulator (SOI) vs. fully-depleted SOI), optimal devices (e.g. multi-threshold voltages process) and optimal bias (weak vs. moderate vs. strong inversion). In the present thesis, we deal with the following analog performance parameters: gain, gain-bandwidth product, MOSFET mismatch in weak inversion and harmonic distortion of MOSFETs in triode regime. We show that SOI transistors are still advantageous over bulk in deep-submicron CMOS technologies and that short-channel SOI transistors can safely be used for mixed-signal operation up to 250°C. The analog ID card can be included in the design flow supported by HDL-AMS. Behavioral models for the basic cells are developed using such languages and further assembled into a ÄÓ modulator with continuous-time integrators as it is a good candidate for low-power consumption and operation at high temperature. The related design issues are assessed using the behavioral models and a design optimization method is presented for a key building block, an active RC integrator with passive resistors.
138

Chemical Abundance Analysis of Population II Stars : The Summary Includes a Background in General Astronomy

Jonsell, Karin January 2005 (has links)
We are made of stardust in the sense that most atomic nuclei around us have been formed by stars. Stars synthesise new elements and expel them to the interstellar medium, from which later new generations of stars are born. We can map this chemical evolution by analysing the atmospheric contents of old Galactic halo stars. I have done two such investigations. A vigourous debate is going on whether the oxygen-to-iron ratio varies strongly with the general metal-content of halo stars. In my first study, I made an abundance analysis of 43 halo stars, and found no support for such a variation. I have also found that there probably is a cosmic spread in the abundances of oxygen, magnesium, silicon, and calcium relative to iron for halo stars. This may be an indication that the halo was built up by subsystems with differences in the star formation rate. In my second study, I performed a thorough abundance analysis of the star HE0338-3945, which is strangely overabundant in both r- and s-elements. Several other stars have been found with abundance patterns curiously similar to this star, and I define new criteria for the class r+s stars. The abundance similarities among the r+s stars suggest a common formation scenario. However, as the s-elements usually are considered to be produced in binary systems of low mass, and r-elements in supernovae of Type II, this scenario is not obvious. In the article I discuss seven hypotheses, and several of them are dismissed.
139

The Effect of an Overall Rating Item on Halo Error in Performance Evaluations

Hogue, S. Elizabeth 01 May 2010 (has links)
This study focuses on how the presence or absence of an overall rating item on a performance evaluation form affects levels of halo error and satisfaction with the form. Participants included undergraduate college students who were randomly assigned to groups receiving a form with or without an overall rating item at the beginning of the form. A satisfaction item was included on both forms. The analyses included a z-test for correlations from independent samples to determine the difference between the two evaluation forms and a t-test to determine the difference between the satisfaction scores of the two forms. The analyses indicated that the differences between the groups were not significant for levels of halo error or satisfaction.
140

Search for the p1/2- resonance in 7he with the 7li(d,2he) reaction and measurement of the deuteron electrodisintegration under 180-deg at the s-dalinac

Ryezayeva, Natalya. Unknown Date (has links)
Techn. University, Diss., 2006--Darmstadt.

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