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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.
281

Lung function in relation to exercise capacity in health and disease

Farkhooy, Amir January 2017 (has links)
Background: Exercise capacity (EC) is widely recognized as a strong and independent predictor of mortality and disease progression in various diseases, including cardiovascular and pulmonary diseases. Furthermore, it is generally accepted that exercise capacity in healthy individuals and in patients suffering from cardiovascular diseases is mainly limited by the maximum cardiac output. Objectives: This thesis investigated the impact of different lung function indices on EC in healthy individuals, patients with cardiovascular disease (e.g., pulmonary hypertension (PH)) and patients with pulmonary disease (e.g., chronic obstructive pulmonary disease (COPD)). Methods: The present thesis is based on cross-sectional and longitudinal analyses of patients suffering from COPD, attending pulmonary rehabilitation at Uppsala University Hospital (studies I and II), and healthy men enrolled in the “Oslo ischemia study” (study IV). Study III is a cross-sectional study of patients suffering from PH attending the San Giovanni Battista University Hospital in Turin. EC was assessed using a bicycle ergometer in studies I and IV, with 12-minute walk tests (12MWT) in study II and with 6-minute walk tests (6MWT) in study III. Extensive pulmonary function tests, including diffusing capacity of the lung (DLCO), were performed in studies I-III and dynamic spirometry was used to assess lung function in study IV. Results: DLCO is more closely linked to decreased levels of EC than airway obstruction in COPD patients. Furthermore, the decline in 12MWT over a 5-year period was mainly explained by deterioration in DLCO in COPD patients. Spirometric parameters indicating airway obstruction significantly related to EC and exercise-induced desaturation in PH patients. A significant, but weak association between lung function parameters and EC was found in healthy subjects and this association is strengthened with increasing age. Conclusion: DLCO is the strongest predictor of low EC and EC decline in COPD. In PH, airway obstruction is strongly related to reduced 6MWT. Therefore, extensive analysis of lung function, including measurements of diffusing capacity, along with standard assessment of airway obstruction, gives a more comprehensive assessment of the functional exercise capacity in patients suffering from pulmonary hypertension or COPD. Lung function is also significantly linked to EC even in healthy subjects, lacking evident cardiopulmonary diseases.
282

A Course in Freshman English Composition Based on Theories of Creativity

Garrett, Patrick Posey 08 1900 (has links)
Today's colleges and universities are faced with the challenges of reforming their curriculums in an effort to hold a generation of students who are now demanding more than just a degree. Today prominent writers in the field of higher education point to the necessity of assessing and reconstructing college courses so that new direction will be provided. Each student entering college for the first time usually must enroll in an English composition course. Such a course offers great potential to encourage the creative capacity of the incoming student and foster an attitude of personal inquiry. The diversity of subjects and intentions which can be introduced in the beginning composition course offers a healthy reservoir of opportunity for exploring personal meaning. Introducing some of the goals and concepts of creativity may thus inspire the design of a new course given to meeting the challenges of higher education.The problem of this study was to develop a course in freshman English composition based on the theories of creativity and directed towards the development of the student's creative and critical capacity.
283

Avaliação da capacidade funcional pós-trauma em idosos / Valuation of functional capacity pos trauma in elderly

Biazin, Damares Tomasin 18 August 2006 (has links)
O estudo teve por objetivo avaliar a capacidade funcional de idosos de 60 a 74 anos, antes do trauma e após 6 meses da alta hospitalar. A pesquisa foi conduzida na linha quantitativa através de um estudo observacional, transversal, realizado de julho a dezembro de 2004. Participaram do estudo 121 idosos, residentes na cidade de Londrina, Pr e Região Metropolitana, que sofreram trauma e foram internados em três hospitais gerais, terciários de Londrina. Após aprovação do Comitê de Ética em Pesquisa, os dados foram coletados, no domicílio, por meio de entrevistas, previamente agendadas, com idosos e seus cuidadores, utilizando-se um instrumento de Avaliação do Perfil Social, Estilo de Vida e Problema de Saúde e a Medida de Independência Funcional (MIF) para avaliação da capacidade funcional, e a análise utilizada foi a estatística descritiva. Os resultados evidenciaram que 59,5% dos idosos eram do sexo masculino e 40,5%, do feminino, com uma média de idade de 67,7 anos, sendo 62,0% casados e 19,8% viúvos. Quanto à escolaridade, 49,6% dos idosos referiram ter o primário. A maioria (76,8%) deles tem renda proveniente de aposentadoria, pensão e/ou aluguel e 78,5% têm casa própria. Os traumas sofridos apresentaram a seguinte distribuição: 62,0% quedas, 25,6% acidentes de transporte e 3,3% agressões e violências. Como conseqüência ao trauma, tiveram uma a três lesões, sendo que a maioria dos homens apresentou traumatismos nos membros inferiores, seguidos por outros nos membros superiores; nas mulheres houve predominância de luxações, entorses e distensões. Após o trauma, 31,4% necessitaram de cuidadores, sendo a maioria mulher, filha do idoso, casada, com idade entre 61 a 70 anos, sem remuneração pelo trabalho, sem outra atividade e com moradia junto ao idoso. Dos 121, a maior parte (51,2%) referiu não ter comorbidade, porém houve a presença de 1, 2 ou 3 e as principais foram: doença do sistema nervoso, doenças osteomusculares e tecido conjuntivo e doenças do aparelho geniturinário. Quanto às questionadas, as principais foram: hipertensão arterial, problemas de visão, tontura, depressão, esquecimento, colesterol elevado, diabetes mellitus, osteoporose, problemas de audição, artrose, incontinência urinária, obesidade, doenças do coração, perda de peso, derrame e artrite. A maioria (82,6%) dos idosos referiu fazer uso de medicamentos de 1 até 9, sendo os tipos mais utilizados: anti-hipertensivos (incluindo os diuréticos), hipoglicemiantes, analgésicos e antiinflamatórios, cardioterápicos e anticonvulsivantes. O trauma foi fatal para 11 idosos (9,1%), os quais eram totalmente independentes antes do mesmo. Dos 110, que sobreviveram, a aplicação da MIF mostrou que o trauma causou maior impacto no domínio motor, com diminuição da capacidade funcional, principalmente nas atividades de autocuidado e locomoção. Quanto ao nível de dependência dos idosos, foi mais evidente na necessidade de até 25% de assistência (dependência mínima). No autocuidado, as atividades que passaram a ter maior dependência, após o trauma, foram no banho e na habilidade de vestir-se abaixo da cintura; na locomoção, o maior impacto foi sentido na marcha e na capacidade para subir e descer escadas. Esses dados mostram que os idosos mais jovens, quando sofrem um trauma, podem ter sua capacidade funcional comprometida, mesmo 6 meses após a ocorrência do evento. / The research aimed to evaluate the functional capacity of younger elderly (60 to 74 years old), before trauma and six months after hospital discharge. The research was conducted in a qualitative line through an observatory and cross-sectional study, realized during the period of June to December of 2004.121 elderlies participated on the study, all residents of the city of Londrina, Pr and the metropolitan area, who had suffered traumas and had been admitted in three general tertiary hospitals, in Londrina. After the approval of the Committee of Ethics in Research, the data was collected in domicile through interviews, previously booked, with elderlies and their caregivers, using an instrument of Valuation of the Social Profile, Life Stile and Health Problem and the Functional Independence Measure (FIM) to the functional capacity valuation, and the analysis used was the descriptive statistical. The results evinced that 59.5% of the elderlies were men and 40.5% were women, with an age average of 67.7 years old, with 62.0% being married and 19.8% widows. Relating to the scholar degree, 49.6% of the elderlies said they had finished the elementary school. Most of the elderlies (76.8%) have an income proceeding from retirement, pension and/or renting and 78.5% have their own house. The traumas suffered by the elderlies present the following distribution: 62.0% a fall, 25.6% transportation accidents, 3.3% aggressions and violence. As a consequence of the trauma, the elderlies had one to three lesions, most of the men had inferior members? injuries, followed by superior members? injuries, and the women had a prevalence of dislocations, sprains and distensions. After the trauma, 31.4% of the elderlies needed caregivers. Most of the caregivers were women, the elderly?s daughter, married, between 61 to 70 years old, did not receive for the work, did not have another activity and lived with the elderly. From the 121 elderlies, most of them (51.2%) reported that they did not have comorbidities, however, there were a presence of 1, 2 or 3 comorbidities reported and the main ones were: nervous system disease, musculoskeletal and connective tissue disease and genitourinary tract diseases. Related to the comorbidities questioned the main ones were: arterial hypertension, vision problems, dizziness, depression, forgetfulness, high cholesterol, diabetes mellitus, osteoporosis, hearing problems, arthrosis, urinary incontinence, obesity, heart diseases, lost of weight, stroke and arthritis. Most of the elderlies (82.6%) reported about using medicines and they consume from 1 to 9 medicines, and the most used ones: antihypertensives (including the diuretics), hypoglycemiants, analgesics and anti-inflammatory drugs, cardiac drugs and anticonvulsants. The trauma was fatal to 11 elderlies (9.1%) who were totally independent before the trauma. From the 110 elderlies who survived from the trauma, the application of the FIM showed that the trauma caused more impact on the motor domain, with a reduction of the functional capacity, mainly on the activities of self-care and locomotion. Related to the level of elderlies? dependence, it was more evinced on the necessity of till 25% of attendance (minimun dependence). On the self-care, the activities that the elderlies started to have more dependence, after the trauma, were the shower and the capacity of getting dressed beneath the waist; on the locomotion, the biggest impact sensed was the pace and the capacity of climb and step down the stairs. This data showed that when the younger elderlies suffer a trauma they may have their functional capacity compromised, even six months after the occurrence of the event.
284

Estudo ab initio da adsorção de átomos de zircônio sobre superfí­cies de óxido de cério: Zrn/CeO2(111) / Ab initio study of zirconium atons adsorption on cerium oxide surfaces: Zrn/CeO2(111)

Mucelini, Johnatan 19 July 2018 (has links)
Catalisadores baseados em óxidos de cério (CeOx, 3/2≤ x ≤ 2) como suporte são utilizados em várias reações de alto interesse econômico, por exemplo as reações de catalizadores de três-vias. Sabe-se que é possível melhorar as propriedade catalíticas da céria, através da mistura com óxido de zircônio e com a adição de partículas metálicas na superfície do material. Entretanto, a deposição de átomos de Zr sobre CeO2(111) é pouco explorada apesar de já ter sido utilizada para a síntese de nanopartículas de Ag de tamanho controlado. Uma das particularidades dos sistemas Zr/CeO2(111) é formar ilhas altura entre 1,5 e 3,0 Å sobre a superfície da céria que são sugeridas na literatura com camadas de Zr-O e O-Zr-O. Entretanto, a natureza e magnitudes das interações entre Zr e CeO2(111) ainda não são totalmente conhecidas, bem como as modificações causadas pelo Zr na superfície de CeO2 e os mecanismos que controlam a oxidação do Zr e a formação de ZrO2 na superfície. Visando entender as interações Zr/CeO2(111) e a formação de ZrO2 sobre CeO2(111), realizou-se um estudo teórico da adsorção de n (1 ≤n ≤ 4) adatomos de Zr sobre CeO2(111), e da formação de ZrO2 sobre CeO2(111). As análises de carga indicam transferências de carga do adatomos de Zr para a superfície e mudança no estado de oxidação das espécies. Os Zr se oxidam á Zr4+ e interagem com O2- da superfície, onde quatro cátions Ce4+ se reduzem á Ce3+. Analises energéticas indicam que o processo é muito estabilizante, mais de 10 eV por Zr. Com o aumento da quantidade n de adatomos de Zr na superfície, observa-se 4 × n reduções de Ce4+ e migrações de O2- de dentro da superfície para próximo dos Zr4+, formando agregados de ZrO2 sobre a superfície. A migração de O se deve a dois fatores, a interação dos O2- com Zr4+ no agregado é mais estável do que a interação dos O2- com Ce3+ dentro da superfície, e a migração de O diminuir a tensão causada pelo maior raio do Ce3+ em relação ao Ce4+. Em adição, foi encontrado uma tendência de estabilidade para os Zr4+ migrarem para sítios Ce dentro da superfície, devido a maior quantidade de coordenações Zr-O e a redução da tensão criada pelos Ce3+. / Cerium oxides (CeOx, 3/2≤ x ≤ 2) based catalysts are employed in several reactions with high economic interest, such as the reaction in three-way-catalysts. It is well know that is possible to improve the ceria catalytic properties, by mixing with zirconium oxide and adding metallic particles over the material surface. Meanwhile, the deposition of Zr atoms over CeO2(111) is little explored although it has already been used for synthesis Ag nanoparticles of controlled size. One of the particularities of the Zr/CeO2(111) systems is to form islands of height between 1,5 and 3,0 Å on the surface of the ceria, which are suggested in the literature to be Zr-O and O-Zr-O layers. However, the nature and magnitudes of interactions between Zr and CeO2 surface are little know, as well as the CeO2 modifications induced by Zr and the mechanisms for Zr oxidation and ZrO2 formation over the surface. Aiming to understand the Zr-CeO2(111) interactions and the ZrO2 formation over the CeO2(111), this mastering project perform a theoretical study of n (1 ≤ n ≤ 4) Zr adatoms absorption over CeO2(111), and the ZrO2 formation over CeO2(111). The charge analysis indicated charge transfer from Zr adatons to the surface together with change in species oxidation state. The Zr oxidize to Zr4+ and interact with surface O2- , where four Ce4+ cations reduce to Ce3+. Energetic analysis pointed out that the process is very stabilizing, more than 10 eV per Zr adatom. With the increase of quantity n of Zr adatoms over the surface, it is observer 4 × n Ce4+ reductions and O2- migrations from inside surface to close the Zr4+, forming ZrO2 aggregates over the surface. The O migration occurs because of two reasons, the O2- interaction with Zr4+ in the agregate is more stabilizer than the interaction of O2- with Ce3+ inside the surface, and the O migration decrease the strain produced bue to the radius of Ce3+ being greater than the Ce4+ radius. In addition, was found a stability trend for Zr4+ to migrate to inside surface Ce sites, due of the more Zr-O coordinations and release of the strain induced by Ce3+.
285

Fundamental Limits of Poisson Channels in Visible Light Communications

Ain-Ul-Aisha, FNU 18 April 2017 (has links)
Visible Light Communications (VLC) has recently emerged as a viable solution for solving the spectrum shortage problem. The idea is to use artificial light sources as medium to communicate with portable devices. In particular, the light sources can be switched on and off with a very high-frequency corresponding to 1s and 0s of digital communication. The high-frequency on-off switching can be detected by electronic devices but not the human eyes, and hence will not affect the light sources' illumination functions. In VLC, if a receiver is equipped with photodiodes that count the number of arriving photons, the channels can be modeled as Poisson channels. Unlike Gaussian channels that are suitable for radio spectrum and have been intensively investigated, Poisson channels are more challenging and are not that well understood. The goal of this thesis is to characterize the fundamental limits of various Poisson channels that models different scenarios in VLC. We first focus on single user Poisson fading channels with time-varying background lights. Our model is motivated by indoor optical wireless communication systems, in which the noise level is affected by the strength of the background light. We study both the single-input single-output (SISO) and the multiple-input and multiple-output (MIMO) channels. For each channel, we consider scenarios with and without delay constraints. For the case without a delay constraint, we characterize the optimal power allocation scheme that maximizes the ergodic capacity. For the case with a strict delay constraint, we characterize the optimal power allocation scheme that minimizes the outage probability. We then extend the study to the multi-user Poisson channels and analyze the sum-rate capacity of two-user Poisson multiple access channels (MAC). We first characterize the sum-rate capacity of the non-symmetric Poisson MAC when each transmitter has a single antenna. We show that, for certain channel parameters, it is optimal for a single-user to transmit to achieve the sum-rate capacity. This is in sharp contrast to the Gaussian MAC, in which both users must transmit, either simultaneously or at different times, in order to achieve the sum-rate capacity. We then characterize the sum-rate capacity of the Poisson MAC with multiple antennas at each transmitter. By converting a non-convex optimization problem with a large number of variables into a non-convex optimization problem with two variables, we show that the sum-rate capacity of the Poisson MAC with multiple transmit antennas is equivalent to a properly constructed Poisson MAC with a single antenna at each transmitter. We further analyze the sum-rate capacity of two-user Poisson MIMO multiple-access channels (MAC), when both the transmitters and the receiver are equipped with multiple antennas. We first characterize the sum-rate capacity of the Poisson MAC when each transmitter has a single antenna and the receiver has multiple antennas. We show that similar to Poisson MISO-MAC channels, for certain channel parameters, it is optimal for a single user to transmit to achieve the sum-rate capacity, and for certain channel parameters, it is optimal for both users to transmit. We then characterize the sum-rate capacity of the channel where both the transmitters and the receiver are equipped with multiple antennas. We show that the sum-rate capacity of the Poisson MAC with multiple transmit antennas is equivalent to a properly constructed Poisson MAC with a single antenna at each transmitter.
286

Proposta de sistemática para análise e gestão de capacidade de produção em empresas de manufatura considerando aspectos econômicos

Valentim, Thiago Leal Sümmchen January 2017 (has links)
Em um mercado competitivo e dinâmico, é fundamental que os sistemas de gerenciamento da produção direcionem seu foco cada vez mais no sentido da busca pela eficiência da gestão econômica. O conhecimento da capacidade produtiva de uma empresa impulsiona a tomada de decisões na busca pela otimização do desempenho operacional e aumento da lucratividade, permitindo o correto posicionamento da empresa em relação à sua demanda e à definição das melhores formas de atendê-la. A discussão teórica sobre capacidade e seus conceitos correlatos tradicionalmente gira em torno de uma conceituação técnica, que trata sobre as restrições físicas do sistema produtivo e abrange noções de volume e tempos de produção, porém não agrega a noção do valor econômico vinculado ao esforço produtivo que o processo pode gerar. Neste contexto, o presente trabalho foca no tema da análise e gestão de capacidade produtiva. Parte-se da lacuna identificada da falta de incorporação de elementos econômicos ao contexto dos estudos sobre capacidade produtiva e da inexistência de uma sistemática estruturada para esta finalidade, que integre as visões técnica e econômica em um modelo unificado. O objetivo principal desta dissertação é a proposição de uma sistemática que apoie a análise e a gestão da capacidade de produção de uma organização, com foco em aspectos econômicos. Para tanto, fundamenta-se na utilização do método de custeio das Unidades de Esforço de Produção (UEPs) como apoio à parametrização técnica e econômica do processo produtivo, bem como no uso de Programação Linear para a modelagem matemática do problema. A sistemática é validada com sua aplicação em um estudo de caso real, e os resultados confirmam a percepção de que um modelo que integra aspectos técnicos e econômicos para a gestão da capacidade produtiva é mais aderente à realidade de uma empresa moderna, e a contraposição destes aspectos permite uma gestão mais robusta da capacidade. / In a competitive and dynamic market, it is imperative that the operations management systems focus increasingly on the pursuit of economic efficiency. The knowledge regarding the production capacity of a company thrusts the decision making process in the direction of operation performance optimization and the increase in profitability, allowing the company to position itself correctly facing its market and to find the correct way to meet its demand. The theoretical discussion regarding capacity and its related concepts traditionally revolves around technical definitions, that deal with physical restraints of the productive system and covers notions of volume and lead times, albeit not adding the notion of the economic value linked to the production effort the system can generate. In this context, the present work focuses on the theme of production capacity analysis and management. Starting from the identified gap of the lack of consideration of economic aspects in the context of production capacity studies and the absence of a structured model to this end, that merges the technical e economic view in a unified model. The main goal of this dissertation is to propose a systematic approach that supports an organization’s production capacity management and analysis, focusing on economic aspects. To that end, it builds on the application of the Unity of Production Effort method (UPE) to support the technical and economical standardization of the productive process, as well as the use of Linear Programming in the mathematical modelling of the problem. The systematic approach is validated through its application on a real case study, and the results confirm the perception that a model that integrates technical and economic aspects to capacity management is more adherent to the reality of the modern company, and the contraposition of said aspects allow for a more robust capacity management.
287

Dynamics of reverse knowledge transfer in MNCs : case studies of an American MNC and its Japanese subsidiary

Ishihara, Hiroyuki January 2017 (has links)
Recently, facing the fierce competition around the world, the headquarters of many MNCs are under pressure to make a decision quickly and effectively for their global marketing strategy. Under such a situation, how effectively the headquarters can obtain knowledge regarding the market situation of subsidiaries around the world is important. In this research, the concept of reverse knowledge transfer is applied to the space of the headquarters' acquisition of knowledge from subsidiaries, from the perspective of decision-making for global marketing strategies. In the extant literature, however, studies on reverse knowledge transfer analyzing the mechanisms dynamically in a multi-faceted way from the perspective of transferring marketing-related knowledge are rare. In order to capture the reverse knowledge transfer mechanisms in a MNC precisely and dynamically, three case studies of the headquarters of an American MNC and its Japanese subsidiary were conducted. Through analysis of the case studies, two new factors were found; one is 'bypass effect', and the other is 'heeding capacity'. By bringing in those new factors, a new dynamic model for reverse knowledge transfer is proposed.
288

Estudo ab initio da adsorção de átomos de zircônio sobre superfí­cies de óxido de cério: Zrn/CeO2(111) / Ab initio study of zirconium atons adsorption on cerium oxide surfaces: Zrn/CeO2(111)

Johnatan Mucelini 19 July 2018 (has links)
Catalisadores baseados em óxidos de cério (CeOx, 3/2≤ x ≤ 2) como suporte são utilizados em várias reações de alto interesse econômico, por exemplo as reações de catalizadores de três-vias. Sabe-se que é possível melhorar as propriedade catalíticas da céria, através da mistura com óxido de zircônio e com a adição de partículas metálicas na superfície do material. Entretanto, a deposição de átomos de Zr sobre CeO2(111) é pouco explorada apesar de já ter sido utilizada para a síntese de nanopartículas de Ag de tamanho controlado. Uma das particularidades dos sistemas Zr/CeO2(111) é formar ilhas altura entre 1,5 e 3,0 Å sobre a superfície da céria que são sugeridas na literatura com camadas de Zr-O e O-Zr-O. Entretanto, a natureza e magnitudes das interações entre Zr e CeO2(111) ainda não são totalmente conhecidas, bem como as modificações causadas pelo Zr na superfície de CeO2 e os mecanismos que controlam a oxidação do Zr e a formação de ZrO2 na superfície. Visando entender as interações Zr/CeO2(111) e a formação de ZrO2 sobre CeO2(111), realizou-se um estudo teórico da adsorção de n (1 ≤n ≤ 4) adatomos de Zr sobre CeO2(111), e da formação de ZrO2 sobre CeO2(111). As análises de carga indicam transferências de carga do adatomos de Zr para a superfície e mudança no estado de oxidação das espécies. Os Zr se oxidam á Zr4+ e interagem com O2- da superfície, onde quatro cátions Ce4+ se reduzem á Ce3+. Analises energéticas indicam que o processo é muito estabilizante, mais de 10 eV por Zr. Com o aumento da quantidade n de adatomos de Zr na superfície, observa-se 4 × n reduções de Ce4+ e migrações de O2- de dentro da superfície para próximo dos Zr4+, formando agregados de ZrO2 sobre a superfície. A migração de O se deve a dois fatores, a interação dos O2- com Zr4+ no agregado é mais estável do que a interação dos O2- com Ce3+ dentro da superfície, e a migração de O diminuir a tensão causada pelo maior raio do Ce3+ em relação ao Ce4+. Em adição, foi encontrado uma tendência de estabilidade para os Zr4+ migrarem para sítios Ce dentro da superfície, devido a maior quantidade de coordenações Zr-O e a redução da tensão criada pelos Ce3+. / Cerium oxides (CeOx, 3/2≤ x ≤ 2) based catalysts are employed in several reactions with high economic interest, such as the reaction in three-way-catalysts. It is well know that is possible to improve the ceria catalytic properties, by mixing with zirconium oxide and adding metallic particles over the material surface. Meanwhile, the deposition of Zr atoms over CeO2(111) is little explored although it has already been used for synthesis Ag nanoparticles of controlled size. One of the particularities of the Zr/CeO2(111) systems is to form islands of height between 1,5 and 3,0 Å on the surface of the ceria, which are suggested in the literature to be Zr-O and O-Zr-O layers. However, the nature and magnitudes of interactions between Zr and CeO2 surface are little know, as well as the CeO2 modifications induced by Zr and the mechanisms for Zr oxidation and ZrO2 formation over the surface. Aiming to understand the Zr-CeO2(111) interactions and the ZrO2 formation over the CeO2(111), this mastering project perform a theoretical study of n (1 ≤ n ≤ 4) Zr adatoms absorption over CeO2(111), and the ZrO2 formation over CeO2(111). The charge analysis indicated charge transfer from Zr adatons to the surface together with change in species oxidation state. The Zr oxidize to Zr4+ and interact with surface O2- , where four Ce4+ cations reduce to Ce3+. Energetic analysis pointed out that the process is very stabilizing, more than 10 eV per Zr adatom. With the increase of quantity n of Zr adatoms over the surface, it is observer 4 × n Ce4+ reductions and O2- migrations from inside surface to close the Zr4+, forming ZrO2 aggregates over the surface. The O migration occurs because of two reasons, the O2- interaction with Zr4+ in the agregate is more stabilizer than the interaction of O2- with Ce3+ inside the surface, and the O migration decrease the strain produced bue to the radius of Ce3+ being greater than the Ce4+ radius. In addition, was found a stability trend for Zr4+ to migrate to inside surface Ce sites, due of the more Zr-O coordinations and release of the strain induced by Ce3+.
289

Hur blir en stad konkurrenskraftig på den internationella kongressmarknaden? : En analys av Stockholm som mötesdestination / How to become a competitive city in the international congress market? : An analysis of Stockholm as a meeting destination

Kostic, Vladica, Mikael, Sjöberg January 2010 (has links)
<p><strong>Background: </strong>The increasing globalization of business and research has led to an increased demand for international meetings. This is a market that a number of countries wish to access and the competition is fierce to get the chance to host major conferences. Stockholm has a pronounced good position in the international meeting market and this essay will examine what it takes to be a successful meeting destination for international congresses.</p><p><strong>Purpose: </strong>The purpose of this thesis is to examine the fundamental factors that must be met for a meeting destination to be successful in the international market for conventions.</p><p><strong>Question at issue:</strong> How can a city develop into a more attractive meeting destination for international congresses?</p><p><strong>Method: </strong>Persons with key positions in the Stockholm meeting industry have been approached by qualitative interviews by the authors.</p><p><strong>Theory: </strong>As a theoretical framework the authors used the value of the physical meeting, generally on the congresses, the planning process for site selection for the meeting, the meeting platform and image.</p><p><strong>Conclusion: </strong>The authors' findings are based on the empirical material gathered during the study interviews. The results from these interviews show the importance of facilities and hotels, availability, and the image.</p> / <p><strong>Bakgrund: </strong>Den ökade globaliseringen av företag och forskning har lett till en ökad efterfrågan av internationella möten. Detta är en marknad som många länder vill ta del av och konkurrensen är hård om att få chansen att arrangera större kongresser. Stockholm har idag en uttalad god position på den internationella mötesmarknaden och denna uppsats ämnar undersöka vad som krävs för att bli en framgångsrik mötesdestination för internationella kongresser.</p><p><strong>Syfte: </strong>Uppsatsens syfte är att undersöka vilka grundläggande faktorer som måste uppfyllas för att en mötesdestination ska bli framgångsrik på den internationella marknaden för kongresser.</p><p><strong>Frågeställning: </strong>Hur kan en stad utvecklas till att bli en mer attraktiv mötesdestination för internationella kongresser?</p><p><strong>Metod: </strong>Författarna har använt sig av kvalitativa intervjuer med några av Stockholms mötesindustris nyckelpersoner.</p><p><strong>Teori: </strong>Som teoretisk referensram har författarna använt sig av värdet av det fysiska mötet, allmänt om kongresser, planeringsprocessen för val av plats för möte, mötesplattformen samt image.</p><p><strong>Slutsats: </strong>Författarnas slutsatser baseras på det empiriska material som insamlats under studiens intervjuer. Resultaten från dessa intervjuer visar på vikten av faciliteter och hotell, tillgänglighet samt image.</p>
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Hur blir en stad konkurrenskraftig på den internationella kongressmarknaden? : En analys av Stockholm som mötesdestination / How to become a competitive city in the international congress market? : An analysis of Stockholm as a meeting destination

Kostic, Vladica, Mikael, Sjöberg January 2010 (has links)
Background: The increasing globalization of business and research has led to an increased demand for international meetings. This is a market that a number of countries wish to access and the competition is fierce to get the chance to host major conferences. Stockholm has a pronounced good position in the international meeting market and this essay will examine what it takes to be a successful meeting destination for international congresses. Purpose: The purpose of this thesis is to examine the fundamental factors that must be met for a meeting destination to be successful in the international market for conventions. Question at issue: How can a city develop into a more attractive meeting destination for international congresses? Method: Persons with key positions in the Stockholm meeting industry have been approached by qualitative interviews by the authors. Theory: As a theoretical framework the authors used the value of the physical meeting, generally on the congresses, the planning process for site selection for the meeting, the meeting platform and image. Conclusion: The authors' findings are based on the empirical material gathered during the study interviews. The results from these interviews show the importance of facilities and hotels, availability, and the image. / Bakgrund: Den ökade globaliseringen av företag och forskning har lett till en ökad efterfrågan av internationella möten. Detta är en marknad som många länder vill ta del av och konkurrensen är hård om att få chansen att arrangera större kongresser. Stockholm har idag en uttalad god position på den internationella mötesmarknaden och denna uppsats ämnar undersöka vad som krävs för att bli en framgångsrik mötesdestination för internationella kongresser. Syfte: Uppsatsens syfte är att undersöka vilka grundläggande faktorer som måste uppfyllas för att en mötesdestination ska bli framgångsrik på den internationella marknaden för kongresser. Frågeställning: Hur kan en stad utvecklas till att bli en mer attraktiv mötesdestination för internationella kongresser? Metod: Författarna har använt sig av kvalitativa intervjuer med några av Stockholms mötesindustris nyckelpersoner. Teori: Som teoretisk referensram har författarna använt sig av värdet av det fysiska mötet, allmänt om kongresser, planeringsprocessen för val av plats för möte, mötesplattformen samt image. Slutsats: Författarnas slutsatser baseras på det empiriska material som insamlats under studiens intervjuer. Resultaten från dessa intervjuer visar på vikten av faciliteter och hotell, tillgänglighet samt image.

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