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Particle Image Velocimetry Near the Leading Edge of a Sikorsky SSC-A09 Wing During Dynamic StallVannelli, Rachel Renee 2011 December 1900 (has links)
Dynamic stall has proven to be a complex problem in helicopter aerodynamics because it limits the helicopter flight regime. Dynamic stall is characterized by drastic increases in lift and a delay of stall due to rapid pitching motions of aerodynamic surfaces. Prediction and control of dynamic stall requires an understanding of the leading edge flow structure.
An investigation was conducted of dynamic stall near the leading edge of a large-scale Sikorsky SSC-A09 airfoil, dynamically pitching about its quarter chord, under realistic helicopter flight conditions (M_infinity = 0.1, k = 0.1, Re_c = 1.0 x 10^6). A testing model with a chord of 0.46 m and a span of 2.13 m was designed and constructed for experimentation in the Dynamic Stall Facility at Texas A&M University. Particle image velocimetry data were recorded for the first 15% of the airfoil chord. Mean velocities, Reynolds stresses, and vorticity were computed. Analyses revealed that during the upstroke, stall onset is delayed in the leading edge region and the first indications of separation are observed at 18 degree angle of attack. The edge of the boundary layer has been characterized for alpha = 18 degrees. The roles of the Reynolds stresses and vorticity are examined.
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Zaměstnanecké benefity pro centra sdílených služeb na BrněnskuVeselý, Milan January 2014 (has links)
Veselý, M. Employee benefits in shared service centre operating in Brno. Di-ploma thesis. Brno: Mendel University of Brno, 2014. The thesis analyzes the current state of employee benefits provided in the shared service centre (SSC) operating in Brno. There is also done a questionnaire survey in selected SSC investigating awareness and satisfaction of employees regarding provided benefits, and in-depth interviews with HR managers of SSC. On the basis of these data, the analysis of the various benefits and of the SSC environment is then designed a general model of employee bene-fits applicable to SSC operating in Brno.
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Expressão de marcadores moleculares em espermatogônias / Expression of molecular markers in spermatogoniaGiassetti, Mariana Ianello 03 June 2015 (has links)
Em mamíferos, a espermatogênese é mantida pela autorrenovação e diferenciação das células-tronco espermatogoniais (SSC). Apesar da grande importância do SSC para a fertilidade masculina, em Bos taurus pouco se sabe sobre a sua identificação e biologia celular. Para roedores, mais de 30 marcadores para células germinativas indiferenciadas já foram descritos. No entanto, ainda não é conhecido um marcador específico apenas para SSC. Quase todos são também expressos por gonócitos, espermatogônias mais diferenciadas ou mesmo células somáticas. Yin Yang 2 (YY2) é um factor de transcrição expresso nas células com a morfologia de gonócitos e SSC, sendo um candidato a marcador de SSC. Assim, a identificação de novos marcadores para SSC e factores que afectam a sua expressão, tais como a idade, são fundamentais para o desenvolvimento da biotecnologia como transgenia e tratamento de infertilidade, nos quais as SSC poderiam ser ferramentas biológicos importantes. Assim, nesta tese temos duas hipóteses principais: 1) a idade do dador afeta a expressão de marcadores moleculares específicos de SSC bovinas assim como potencial de células-tronco dessas células e que as sequências de DNA em que se associa YY2 regulam a expressão génica de SSC em camundongos. Os objetivos específicos, organizados em 4 artigos científicos, foram: identificar a melhor plaqueamento diferencial para enriquecer SSC bovina (artigo 1), verificar se a expressão de marcadores moleculares de SSC bovina difere entre adultos pré-púberes (artigo 2 e 3), identificar novos marcadores específicos para SSC em Bos taurus (artigo 3), verificar que a idade afeta o potencial de célula-tronco de SSC bovinas (artigo 3), descrever YY2 como um marcador específico para SSC em camundongos e verificar se as sequências DNA associadas YY2 são loci de importância para SSC. Assim, definimos o melhor plaqueamento diferencial para o enriquecimento de SSC bovinas, que idade afeta a expressão marcadores já estabelecidos assim como genes específicos do transcriptoma de SSC bovinas e que idade também afeta o seu potencial de células-tronco (ensaio de repopulação). Concluímos também que YY2 é um marcador para SSC de camundongo em cultivo, em animais adultos e que as sequências do genoma que se associam YY2 possivelmente tem capacidade de regulação génica em SSC murina. / Mammalian spermatogenesis is sustained by self-renewal and differentiation of spermatogonial stem cells (SSC). Despite the importance of the SSC for male fertility, in Bos taurus líttle is known about their identification identity and cell biology. For rodents, more than thirty markers for undifferentiated germ cells have already been described. However, none of these represents a marker specific for SSC, as most are also expressed in gonocytes, differentiated spermatogonia or even somatic cells. Yin Yang 2 (YY2) is a transcription factor specifically expressed in cells with the morphology of gonocytes and SSC in the mouse, being a candidate marker for SSC. For the use of SSC as an important biological tool in the development of biotechnology such as transgenesis and the treatment of infertility, it is important to identify new markers for SSC and factors that affect their expression, such as the age of donors. Therefore, the experimental work described in this thesis was based on two main hypothesis: (1) the donor age affects the expression of specific molecular markers in SSC as well their potential as stem cells and 2) YY2 exerts important functions in SSC and genomic targets correspond to loci relevant for gene regulation or genome management in SSC. The specific goals have been organized in 4 manuscripts as follows: optimization of differential plating to enrich for bovine SSC (Article 1), check if the expression of molecular markers of bovine SSCs differs between prepubertal and adult donors (Article 2 and 3), identify new markers specific for SSC in Bos taurus (Article 3), continuation of the initial description of YY2 as a specific marker for SSC in mice and check if sequences bound by YY2 in vivo harbor the capacity to influence gene expression in SSC. As conclusions, we present an optimized differential plating protocol for the enrichment of bovine SSC, we conclude that age effects the expression of SSC markers, the expression of specific genes of bovine SSC and that age also affects their potential as stem cells (measured in repopulation assays). We also contribute to the description of the restricted expression of YY2 in prepuberal and adult SSC in mice and we show that YY2 binding sites represent genomic sequences relevant for control of gene expression.
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Vergleichende Genomanalyse bei Mensch und Schwein am Beispiel ausgewählter syntenischer Regionen des humanen Chromosoms 6 / Comparative genome analysis of defined syntenic regions of human and porcine chromosomsDuscher, Sonja 03 May 2001 (has links)
No description available.
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Koncern som tillväxtinkubator för småföretag : – En fallstudie i ett shared service centers möjligheter attstödja entreprenöriella småföretag / Business Group as Growth Incubator for SMEs : – A Case Study Concerning a Shared Service Center’sPossibilities of Supporting Small and Medium-sizedEntrepreneurial EnterprisesEurenius Hallgren, Albin January 2011 (has links)
No description available.
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Synoptic Atmospheric Conditions, Land Cover, and Equivalent Temperature Variations in KentuckyNa-Yemeh, Dorothy Yemaa 01 April 2017 (has links)
Research has demonstrated that equivalent temperature (TE), which incorporates both the surface air temperature (T) and moist heat content associated with atmospheric moisture, is a better indicator of overall heat content. This thesis follows up on a study that used TE to determine the impacts of land use/land cover and air masses on the atmospheric heat content over Kentucky during the growing season (April-September). The study, which used data from the Kentucky Mesonet, reveals that moist weather types dominate the growing season and, as expected, differences between T and TE are smaller under dry atmospheric conditions but larger under moist conditions. For example, the lowest TE-T difference was 10.04 °C on a dry weather day on the 18th of April, 2010 (T = 8.91 °C and TE = 18.95 °C). On the other hand, the highest estimated difference for a day of moist tropical weather was 46.54 °C on the 11th of August, 2010 (T = 26.54 °C and TE = 73.08 °C). Since land cover type influences both moisture availability and temperature in the lower atmosphere, the research shows that TE is larger in areas with higher physical evaporation and transpiration rates. Results support the hypothesis that the influence of different weather types over a region is a likely cause of interannual variation in TE.
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Fatores de resistência ao processo de implementação de um centro de serviços compartilhados : uma abordagem segundo a teoria institucional / Resistance factors in the process of implementing a shared service center : an approach in theory institutionalBerdejo, Ludwig Miguel Agurto 03 September 2009 (has links)
A presente pesquisa procura estudar uma mudança organizacional de larga escala em uma rede hoteleira multinacional. Esta mudança tem como foco a implementação de um Centro de Serviços Compartilhados (CSC) que passa a realizar de forma centralizada as rotinas e processos administrativos, contábeis e financeiros de mais de quarenta unidades hoteleiras do grupo. Na implementação de mudanças desta magnitude, é necessário lidar com as resistências internas da organização que se apresentam no decorrer do processo. Neste sentido, esta pesquisa objetiva estudar quais são as principais resistências que envolvem um processo de mudança, tomando como ponto base os elementos da resistência apontados por Burns e Scapens (2000). Este construto foi desenvolvido para dar um foco intraorganizacional aos processos de mudança, sendo influenciado pela Old Institutional Economics (OIE), e procura sanar algumas críticas postas às primeiras pesquisas da New Institutional Sociology (NIS) pelas quais esta última estaria descrevendo os processos de mudança como lineares e inevitáveis, nos quais os atores se tornavam voluntariamente isomórficos às instituições. Com base neste construto, este trabalho procura analisar os elementos de resistência (i) por existência de conflito de interesses; (ii) por falta de competência (conhecimento e / ou experiência); e (iii) por apego às instituições postas no ambiente, identificando quais são as mais importantes e como estas resistências se relacionam ao processo de institucionalização posto por Burns e Scapens (2000), no processo de codificação, incorporação, repetição e institucionalização. Assim, por meio de um estudo descritivo, com o uso de técnicas qualitativas e quantitativas, entrevistas, questionários e das ferramentas multivariadas Análise de Conglomerados, Análise de Correspondência (ANACOR), análise de homogeneidade (HOMALS) e da Categorical Principal Component Analysys (CAPTCA), procura-se analisar e observar como os gestores operacionais (gerentes gerais e subgerentes das unidades hoteleiras) e os gestores corporativos (alta diretoria e condutores da mudança) assimilam e percebem a mudança promovida pela implementação de um CSC. O CSC, por sua vez um modelo recente nas organizações, foi implementado para 42 unidades hoteleiras do grupo, distribuídas em cinco marcas com características distintas, através de um cronograma de migração de dezoito meses de duração. Os achados permitem concluir que as principais resistências existentes ao processo estão relacionadas com a resistência por falta de competência e por apego às instituições existentes. É preciso considerar que os elementos da resistência estão todos eles entrelaçados e todos devem ser analisados em planos de ação que visem à institucionalização completa no novo modelo do CSC. Os resultados desta pesquisa levantam insumos para considerar que a identificação das principais resistências em um processo de institucionalização, dentro do construto descrito por Burns e Scapens (2000), é bastante útil para direcionar ações e estratégias que visem à completa institucionalização do modelo. Nestes estudo, a análise dos elementos da resistência lança luz sobre as possíveis causas da resistência dos gestores operacionais pela falta de conhecimento principalmente com os temas essenciais relacionados à análise das informações contábeis e financeiras. Adicionalmente, levantam-se argumentos sobre as possíveis causas da resistência destes mesmos gestores por apego às instituições, especificamente nas marcas superiores, onde se demandam informações específicas e diferenciadas em função da complexidade maior destas unidades. Ambas as conclusões servem como um importante direcionador, tanto para a organização foco de estudo como para outras organizações que passem por processos de mudança similares ou que estejam procurando implementar um centro de serviços compartilhados, solução recente e em franca expansão no Brasil. / The following research brings a study on a large-scale organizational change in an international hotel chain. The change has as its focus the implementation of a Shared Service Center (SSC) that accomplishes the administrative, accounting and financial processes in a centralized way in more than forty hotel unities of the group. In order to implement changes of such magnitude, it is necessary to deal with internal resistances within the organization that appear during the process. In this sense, this research aims to study which are the main resistances involved in a change process, based on the resistance elements indicated by Burns and Scapens (2000). Influenced by the Old Institutional Economics (OIE), the present research has been developed to bring an intra-organizational focus to the change processes, and it intends to solve some criticism brought toward the first researches developed by the New Institutional Sociology (NIS). Those researches would describe the change processes as being linear and unavoidable, and, through such processes, the actors supposedly became voluntarily isomorphic to the institutions. Based on those ideas, this paper intends to analyze the following elements of resistance: (i) formal and overt due to competing interests; (ii) by lack of capability (knowledge and experience); and (iii) by attachment to the institutions set in the environment, identifying which are the most important resistances and how they would relate to the process of institutionalization considered by Burns and Scapens (2000) in the encoding, enacting, reproduction and institutionalization process. Thus, through descriptive research, using qualitative and quantitative techniques, interviews, surveys and through multivariate analysis such as Conglomerate Analysis, Correspondence Analysis (ANACOR), Homogeneity Analysis (HOMALS) and Categorical Principal Component Analysis (CAPTCA), the research aims to analyze and observe how operational managers (general managers and assistant managers of the hotel unities) and corporative managers (board members) assimilate and realize the change promoted by the implementation of a SSC. On its turn, the SSC, being a recent model on the organizations, was implemented in 42 hotel unities of the group, distributed in five brands with distinct characteristics, through a migration chronogram lasting 18 months. The findings led to the conclusion that the main resistances to the process are related to the resistance by lack of capability and by attachment to the existing institutions. It is necessary to consider that the elements of the resistance are interconnected, and they should be analyzed in action plans aiming the complete institutionalization within the new model of the SSC. The results of this research bring inputs to consider that the identification of the main resistances in an institutionalization process, as described by Burns and Scarpens (2000). Those inputs are very useful to lead actions and strategies, in order to guide the complete institutionalization of the model. In this specific case observed, the analysis of the elements of resistance illuminates the possible reasons for which there is, by the operational managers, resistance by lack of knowledge, resistance which is mainly connected to the essential subjects related to the analysis of accounting and financial information. Additionally, the research raises arguments on the possible causes of the resistance of such operational managers, caused by attachment to the institutions, specifically on the superior brands, in which there is a demand for specific and different information because of the complexity of those unities when compared to the economical brands. The conclusions work as an important guide, both to the organization focused in this study and to the ones that possibly may go through similar change processes or that may be trying to implement a center of shared services, a recent solution that is in expansion in Brazil.
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Barriers to Implementation and Strategies to Improve Adherence to the Sepsis BundlesAmistad, Rowena 01 January 2019 (has links)
Sepsis is associated with high mortality and morbidity. Immediate recognition and treatment is crucial to prevent complications that can be highly detrimental and cause a significant impact on the U.S. healthcare economy. Numerous studies have been conducted to improve patient outcomes and lower healthcare costs from sepsis and septic shock. Many of these studies were focused on exploring healthcare providers' knowledge and compliance to the Surviving Sepsis Campaign (SSC) guidelines. This study aimed to explore and identify barriers to the implementation of the sepsis bundles and strategies to enhance healthcare providers' adherence to these bundles. A systematic review of articles was conducted using the ACE Star Model of Knowledge Transformation. Studies such as randomized controlled trials (RTC's), systematic reviews, retrospective studies, and prospective observational studies conducted in Intensive Care Units (ICUs) within the past 10 years were utilized, guided by the American Association of Critical Care Nurses' (AACN's) grading system. Sources of evidence were obtained from PubMed, CINAHL, and GoogleScholar. The results of this study are aimed at helping support the evidence-based clinical practice among providers caring for patients with sepsis and septic shock in an ICU setting using evidence-based guidelines. The results of this study provide an opportunity for healthcare systems to relieve financial burdens from sepsis and thus contribute to pos
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Sulfide stress cracking resistance of API-X100 high strength low alloy steel in H2S environmentsAlmansour, Mansour A. 05 1900 (has links)
Sulfide Stress Cracking (SSC) resistance of the newly developed API-X100 High Strength Low Alloy (HSLA) steel was investigated in the NACE TM0177 "A" solution. The NACE TM0177 "A" solution is a hydrogen sulfide (H2S) saturated solution containing 5.0 wt.% sodium chloride (NaC1) and 0.5 wt.% acetic acid (CH3COOH). The aim of this thesis was to study the effect of microstructure, non-metallic inclusions and alloying elements of the X100 on H2S corrosion and SSC susceptibility. The study was conducted by means of electrochemical polarization techniques and constant load (proof ring) testing. Microstructural analysis and electrochemical polarization results for X100were compared with those for X80, an older generation HSLA steel. Uniaxial constant load SSC testing was conducted using X100 samples and the results were compared with those reported for older generation HSLA steels.
Addition of H2S to the NACE TM0177 "A" solution increased the corrosion rate of X100from 51.6 to 96.7 mpy. The effect of H2S on the corrosion rate was similar for X80. The corrosion rate for X80 increased from 45.2 to 80.2 mpy when H2S was added to the test solution. Addition of H2S enhanced the anodic kinetics by forming a catalyst (FeHSads) on the metal surface and as a result, shifted the anodic polarization curve to more current densities. Moreover, the cathodic half cell potential increased due to the decrease in pH, from 2.9 to 2.7, which shifted the cathodic polarization curve to more current densities. The increase in both the anodic and cathodic currents, after H2S addition, caused the rise in the corrosion current density.
In H2S saturated NACE TM-0177 "A" solution, the X100 steel corrosion rate was higher than the X80 steel by 20%. Longer phase boundaries and larger nonmetallic inclusions in the X100 microstructure generated more areas with dissimilar corrosion potentials and therefore, a stronger driving force for corrosion. Higher density of second phase regions and larger nonmetallic inclusions acted as an increased cathode area on the X100 surface which increased the cathodic current density and consequently, increased the corrosion current density.
Proof ring tests on the X100 gave a threshold stress value, C5th, of 46% YS, 343.1 MPa(49.7 ksi). The main failure was caused by SSC cracking. SSC nucleated at corrosion pits on the metal surface and microcracks in the metal body and propagated perpendicular to the applied stress. Hydrogen Induced Cracking (HIC) was observed in the X100. HIC cracks nucleated at banded martensite-ferrite interfaces and propagated along the rolling direction parallel to the applied tensile stress through the softer ferrite phase.
When compared to older HSLA grades, the X100 tested in this study had a high SSC susceptibility and therefore, is not be recommended for H2S service applications. The high X100 SSC susceptibility was caused by the material high corrosion rates in H2Smedia which formed corrosion pits that acted as crack initiation sites on the metal surface and provided more hydrogen that migrated into the steel. In addition, the X100
inhomogeneous microstructure provided a high density of hydrogen traps in front of the main crack tip which promoted SSC microcrack formation inside the metal. Microcracks in the metal body connected with the main crack tip that originated from corrosion pits which assisted SSC propagation.
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Sulfide stress cracking resistance of API-X100 high strength low alloy steel in H2S environmentsAlmansour, Mansour A. 05 1900 (has links)
Sulfide Stress Cracking (SSC) resistance of the newly developed API-X100 High Strength Low Alloy (HSLA) steel was investigated in the NACE TM0177 "A" solution. The NACE TM0177 "A" solution is a hydrogen sulfide (H2S) saturated solution containing 5.0 wt.% sodium chloride (NaC1) and 0.5 wt.% acetic acid (CH3COOH). The aim of this thesis was to study the effect of microstructure, non-metallic inclusions and alloying elements of the X100 on H2S corrosion and SSC susceptibility. The study was conducted by means of electrochemical polarization techniques and constant load (proof ring) testing. Microstructural analysis and electrochemical polarization results for X100were compared with those for X80, an older generation HSLA steel. Uniaxial constant load SSC testing was conducted using X100 samples and the results were compared with those reported for older generation HSLA steels.
Addition of H2S to the NACE TM0177 "A" solution increased the corrosion rate of X100from 51.6 to 96.7 mpy. The effect of H2S on the corrosion rate was similar for X80. The corrosion rate for X80 increased from 45.2 to 80.2 mpy when H2S was added to the test solution. Addition of H2S enhanced the anodic kinetics by forming a catalyst (FeHSads) on the metal surface and as a result, shifted the anodic polarization curve to more current densities. Moreover, the cathodic half cell potential increased due to the decrease in pH, from 2.9 to 2.7, which shifted the cathodic polarization curve to more current densities. The increase in both the anodic and cathodic currents, after H2S addition, caused the rise in the corrosion current density.
In H2S saturated NACE TM-0177 "A" solution, the X100 steel corrosion rate was higher than the X80 steel by 20%. Longer phase boundaries and larger nonmetallic inclusions in the X100 microstructure generated more areas with dissimilar corrosion potentials and therefore, a stronger driving force for corrosion. Higher density of second phase regions and larger nonmetallic inclusions acted as an increased cathode area on the X100 surface which increased the cathodic current density and consequently, increased the corrosion current density.
Proof ring tests on the X100 gave a threshold stress value, C5th, of 46% YS, 343.1 MPa(49.7 ksi). The main failure was caused by SSC cracking. SSC nucleated at corrosion pits on the metal surface and microcracks in the metal body and propagated perpendicular to the applied stress. Hydrogen Induced Cracking (HIC) was observed in the X100. HIC cracks nucleated at banded martensite-ferrite interfaces and propagated along the rolling direction parallel to the applied tensile stress through the softer ferrite phase.
When compared to older HSLA grades, the X100 tested in this study had a high SSC susceptibility and therefore, is not be recommended for H2S service applications. The high X100 SSC susceptibility was caused by the material high corrosion rates in H2Smedia which formed corrosion pits that acted as crack initiation sites on the metal surface and provided more hydrogen that migrated into the steel. In addition, the X100
inhomogeneous microstructure provided a high density of hydrogen traps in front of the main crack tip which promoted SSC microcrack formation inside the metal. Microcracks in the metal body connected with the main crack tip that originated from corrosion pits which assisted SSC propagation.
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