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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.
41

Fontes de vantagens competitivas em empresas do setor coureiro calçadista

Stein, Carle 26 September 2010 (has links)
Made available in DSpace on 2019-03-29T23:26:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-26 / Compreender e definir as estratégias para um bom desempenho no mercado tem sido uma tarefa difícil para as organizações de qualquer segmento de atuação. O desempenho de uma empresa não é necessariamente determinado pelo ambiente competitivo da indústria, onde as ideias e ações das próprias empresas podem moldar o panorama econômico e industrial (KIM; MAUBORGNE, 2009). Em virtude desse fato, este estudo buscou identificar o impacto dos fatores estruturais e dos fatores específicos à firma, no nível de vantagens competitivas das empresas. O segmento estudado foi o calçadista, onde a pesquisa foi realizada na região do Vale do Cariri, localizada no Estado do Ceará. O tipo de pesquisa foi aplicada e tem natureza descritiva. O método de pesquisa utilizado foi o quantitativo. Os dados coletados referem-se ao período de 2010, no qual foram pesquisadas 16 empresas calçadistas da região estudada. O setor calçadista do Vale do Cariri apresenta-se organizado em clusters com evidências de evolução, onde entre os mudanças observadas destaca-se uma maior preocupação das empresas pela qualidade dos calçados fabricados, uma redução da relevância do custo como fator principal de competitividade e o surgimento formal de cooperação entre as empresas. Constatou-se que a estratégia predominante adotada pelas empresas no cluster foi a baseada na estrutura com origem no ambiente externo, cujos fatores que apresentaram maior relevância na pesquisa realizada foram os ligados a fonte de financiamento, grau de competitividade das matérias-primas e numero de fornecedores de insumos. As empresas com estratégias baseadas em seus recursos e capacidades foram as que apresentaram o maior nível de competitividade sustentável no cluster estudado, cujos fatores que apresentaram maior relevância na pesquisa realizada foram os pertinentes ao desenvolvimento e design de produtos o os ligados ao gerenciamento eficiente das operações. Assim, apesar do segmento calçadista apresentar historicamente o movimento estratégico de formação de aglomerações, onde as indústrias buscam a obtenção de competitividade baseada nas vantagens obtidas na estrutura, observou-se que foram os fatores específicos à firma os que mais afetaram o nível de vantagens competitivas das empresas do cluster estudado.
42

A estratégia de cluster na geração de vantagem competitiva : a fruticultura irrigada no agropólo do baxio Jaguaribe-CE

Alves, Eugenio Pacelli 16 October 2003 (has links)
Made available in DSpace on 2019-04-05T23:01:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-10-16 / Now, the promotion of the local and regional development, through the sectorial and geographical concentration of companies - particularly those of small and medium load - it constitutes the focus of several analysts' of the regional development interest. Basing on the average literature related to the theory of the economical clusters and of the local productive systems, the proposal of this work consisted of to characterize and to analyze the productive structure of the business area of AGROPÓLO of Low Jaguaribe, in the north of Ceará, where the horticulture is developed irrigated for melon production, being emphasized the capacity of systematic export and the degree of existent relationships mainly between the rural producers and some linked agents to the system agroindustrial of the melon. Besides the theoretical referencial, the study was also based in the empiric evidences of results obtained starting from the adoption of the system of clusters in certain setores/atividades, in some developing countries. The study in subject epistemologicamente is based in the Positivism and his/her analysis leaves of a field research accomplished in a population of companies of the section. The data were collected in the first semester of 2003 through interviews with the proprietors of the companies. The central hypothesis of this work sustains that the implantation of the model AGROPÓLO in Low Jaguaribe, idealized in agreement with the cluster system, it was an efficient strategy in the generation of competitive advantages for the companies producing of melon in this area measured by the capacity of systematic export. A secondary hypothesis was lifted up, to know: the company group that reached the largest degree of competitiveness, measured for the largest time of permanence in the external market, it was what reached the largest integration degree with the productive atmosphere. After the analysis of the results of the research, it was observed that the central hypothesis was confirmed, once the group of the producing of melon reached a degree of competitiveness of 3,2 in a scale from 1 to 4, classified as "Competitive". the secondary hypothesis was also confirmed, therefore the group that reached larger degree of competitiveness reached the largest integration degree with the external atmosphere, comparatively to the less competitive groups. At the end of the research, it was evident the positive relationship between competitiveness of the producing of melon and his/her integration with the external atmosphere in AGROPÓLO of Low Jaguaribe. It was observed that the competitiveness of the companies is anchored so much in absolute natural advantages as in competitive advantages, but those last ones were not still enough so that the producers acted at markets of nobler species and of larger duration, conquered by more competitive areas. Although the field research has had as focus the organization of the production, it was noticed that the presence of the public research in AGROPÓLO is still considered incipient, in spite of the efforts of institutions as CENTEC in Lemon tree of the North. It was identified, the non participation of the initiative deprived in the effort of developing research for best cultivate, besides as for the financing of those actions. The formation of a competitive atmosphere in the area of Low Jaguaribe lacks, therefore, of a more effective integration level between the infrastructure of the local public innovation and their private agents. That integration should increase the capacity of the producers act at the most competitive markets and to give larger sustainability in the permanence in the external market, demonstrating, in consonance with the international literature related to the cluster model, that difficultly competitive and innovative producers will exist in an area that is not competitive and innovative. Keywords: Clusters. Competitiveness. Fruticultura. / Baseando-se na literatura corrente relacionada à teoria dos Clusters econômicos e dos Sistemas Produtivos locais (SPL), a proposta deste trabalho consistiu em caracterizar e analisar a estrutura para produção de melão do AGROPÓLO do Baixo Jaguaribe, no norte do Ceará, onde é desenvolvida a fruticultura irrigada, enfatizando-se principalmente a capacidade de exportação sistemática e o grau de relacionamentos existentes entre os produtores rurais e alguns agentes externos ligados ao sistema agro-industrial do melão. Além do referencial teórico, o estudo fundamentou-se também nas evidências empíricas de resultados obtidos a partir da adoção do sistema de clusters em determinados setores em algumas regiões do país. O estudo parte de uma pesquisa de campo realizada na população de empresas do setor. Os dados foram coletados no primeiro semestre de 2003 por meio de entrevistas com os proprietários das empresas. Após a análise dos resultados da pesquisa, observou-se que o grupo dos produtores de melão que atingiu o maior grau de competitividade foi o grupo que atingiu o maior grau de integração com o ambiente externo, comparativamente aos grupos menos competitivos. Ao final da pesquisa, ficou evidente a relação positiva entre competitividade dos produtores de melão e sua integração com o ambiente externo à empresa. Embora a pesquisa de campo tenha tido como foco a organização da produção, percebeu-se que a presença da pesquisa pública no AGROPÓLO é considerada ainda incipiente, portanto, a formação de um ambiente competitivo na região do Baixo Jaguaribe carece de um nível de integração mais efetivo entre a infra-estrutura da inovação pública local e os seus agentes privados. Essa integração deve aumentar a capacidade dos produtores atuarem nos mercados mais competitivos e dar maior sustentabilidade na permanência no mercado externo, demonstrando, em consonância com a literatura internacional relacionada ao modelo de cluster, que dificilmente existirão produtores competitivos e inovadores em uma região que não seja competitiva e inovadora. Palavras-chave: Clusters. Competitividade. Fruticultura.
43

The origin and evolution of the galactic globular cluster system

Alexander, Poul Edwin Rennie January 2015 (has links)
No description available.
44

SYNTHESES, STRUCTURES AND PROPERTIES OF MULTINUCLEAR COPPER CLUSTERS AND BIOLOGICALLY RELEVANT MOLYBDENUM COMPLEXES

January 2019 (has links)
archives@tulane.edu / Metalloenzymes containing copper or molybdenum have attracted considerable attention during the past several decades, as they play significant roles in a variety of biological and chemical areas. In those enzymes, their active sites exhibit unique structural features for fundamental studies in coordination chemistry and for applications in various catalytic reactions. The work described in this dissertation focuses on systematic syntheses of organometallic complexes for use in enzymatic systems as nitrous-oxide reductases (N2OR), acetyl-CoA (acetyl coenzyme A) synthases, or carbon monoxide dehydrogenases (ACS/CODH). Synthesis of diaminobisthiolate (N2S2) ligands with phenyl-connected sulfur and nitrogen atoms are introduced in Chapter 1. The importance of the N2S2 donor atoms in functionalizing the overall enzyme active sites are discussed in Chapter 1. Compared to the previously reported procedures, the new routes in this work allow for improved synthetic control, resulting in enhanced synthetic yields under mild reaction conditions. In Chapter 2, we focus on the synthesis, characterizations and applications of Ni(N2S2) complexes. We start with a new Ni complex with a tetradentate diaminobisthiolate ligand which is a continuation of one of the focuses in the previous chapter. The differences between the new Ni(N2S2) complex and other previously reported complexes with similar structures are discussed. We use both theoretical method (density functional theory calculation) and electrochemical measurements to explore the structural-property characteristics of those complexes. Chapter 3 details the synthesis of several multi-copper clusters for assembling in CuZ active-site analogues for nitrous oxide reduction. In those complexes, tetradentate diaminobisthiolate (N2S2) is used as a backbone ligand. Those complexes exhibit unique redox features due to the mixed valence of the CuI/CuII couple. Their structures are characterized by detailed X-ray crystallography measurements. In chapter 4, we extend the studies in synthesizing analogues in molybdenum- dependent carbon monoxide dehydrogenases (Mo-CODH) active site. Two different synthetic routes are explored to yield a number of Mo- and Cu-based complexes. Electrochemical characterizations are used to investigate the redox features of those complexes. / 1 / bo Wang
45

The effects of merging and environment on galaxies and clusters of galaxies

Owers, Matthew Scott, Physics, Faculty of Science, UNSW January 2008 (has links)
This thesis addresses two fundamental questions in astrophysics: (i) To what extent is environment a driver of galaxy evolution? And (ii) How does hierarchical structure formation affect the galaxy environment? The former is addressed by examining the environments of starburst galaxies, the latter by examining clusters undergoing major mergers with focus placed on the efficacy of ??cold fronts?? in identifying systems that have recently undergone a major merger - an essential first step to understanding their impact. For the first of these studies, the 2dFGRS was exploited to select large samples of starburst galaxies. These were used to derive measurements of the local and large-scale environments, clustering properties, and morphologies of starburst galaxies. It is found local environment is most germane in terms of a starburst triggering mechanism, with the starburst galaxies showing an excess of close (<20 kpc) neighbours with comparable luminosity/mass, while 20-30% exhibit a morphology consistent with them being involved in an ongoing tidal/merger interaction. On large scales (5-15 Mpc), the starburst galaxies were found to be much less clustered compared to the overall 2dFGRS population, and were not preferentially found in rich clusters with just over half residing in low to intermediate luminosity groups. However, in a number of cases, evidence for obvious local environmental influences was lacking, indicating starbursts can also be internally driven. For the latter study, the Chandra, archive was used to select a sample of clusters exhibiting ??cold front?? features. Selection required the presence of significant density jumps (>1.5 at the lower 90% CI) in the intracluster medium and for the gas on the denser side of the front to be cooler. From this sample, the clusters Abell 1201, Abell 2163, RXJ1720.1+2638, and Abell 3667 were targeted for comprehensive spectroscopic follow-up at optical wavelengths using the 3.9m Anglo Australian and 6.5m Multiple Mirror Telescopes. Using 321 spectroscopically confirmed members for Abell 1201, 550 for Abell 3667 and 491 for Abell 2163 it is shown that these clusters contain substructure which can be directly related to the cold fronts, whilst for 335 confirmed members in RXJ1720.1+2638 promising evidence exists for merger activity related to the cold front. Despite the range of different types of cold fronts and substructures detected, it is clear that cold fronts are robust signposts of merger activity.
46

Secondary ion emission from single massive gold cluster impacts

Hager, George Joseph 17 September 2007 (has links)
Secondary ion mass spectrometry, SIMS, is one of the most versatile surface analytical techniques. The significant parameter determining the performance of SIMS is the secondary ion yield. Atomic projectiles, traditionally used in SIMS, are an inefficient method to desorb and generate secondary ions. The use of poly-atomic projectiles, such as (CsI)nCs, Au3, SF5 and C60, has been demonstrated to be an effective means to enhance secondary ion yields. Still larger secondary ion yields can be obtained with massive gold clusters, specifically Au4004+. Secondary ion yields from organic targets approach unity and are in excess of unity for selected inorganic targets. This dissertation is a first study of the secondary ion emission characteristics resulting from surface bombardment of keV Au400. The enhanced secondary ion yields from these massive clusters resulted in a need to detect isobaric secondary ions. An eight-anode detector was designed, built and implemented to study secondary ion emission resulting from massive projectile impacts. Secondary ion yield enhancements, resulting from use of the multi-anode detector, are reported along with secondary ion distributions for organic and inorganic targets. Au-adduct ions have been observed in mass spectra resulting form organic and inorganic targets bombarded by Au400. Data indicate that these adducts are a result of projectile/surface molecule interactions and not a product of Au implantation. Secondary ion yields of these adducts are reported. Although these adduct ion yields are an order of magnitude lower than the non-adduct ions, we have demonstrated their potential usefulness in analytical applications, such as examining surface homogeneity. Finally, these novel projectiles have been used to examine secondary ion emission from targets with different structural properties which have the same stoichiometry. In a comparative study, we have measured a significant difference in secondary ion emission and yields from the two systems, graphite and α-ZrP. Au400, at 136 keV, is effective in terms of secondary ion yield and secondary ion multiplicity enhancement. When used in the event-by-event bombardment/detection mode, the desorption volume has a diameter between 10-20 nm with and emission depth of approximately 5 nm, perturbing less than an attomole of analyte.
47

Stellar masses of star forming galaxies in clusters

Randriamampandry, Solohery January 2010 (has links)
No description available.
48

The Relationship Between Active Galactic Nuclei and Metal-enriched Outflows in Galaxy Clusters

Kirkpatrick, Charles January 2012 (has links)
Clusters of galaxies are host to powerful Active Galactic Nuclei (AGN) that greatly affect the thermal history of clusters. By keeping X-ray emitting gas from cooling, massive, run away star formation does not occur in the brightest cluster galaxy (BCG). This is achieved through radio jets displacing large quantities of metal-rich gas and carving out cavities in the intracluster medium (ICM). This metal-rich gas was originally formed within the BCG and ejected through type Ia supernovae. The current distribution of the ejecta suggests an extra source of energy has spread the material far out into the ICM. Currently, it is unclear what mechanisms are responsible. In this thesis, I present evidence, in the form of X-ray imaging and spectra, that establishes a link between AGN and the observed distribution of metal-rich gas. First, the BCG in the Abell 1664 cluster is unusually blue and is forming stars at a rate of ~23 solar masses per year. The BCG is located within 5 kpc of the X-ray peak, where the cooling time of 3.5×10^8 yr and entropy of 10.4 keV cm^2 are consistent with other star-forming BCGs in cooling flow clusters. The cooling rate in this region is roughly consistent with the star formation rate, suggesting that the hot gas is condensing onto the BCG. We use the scaling relations of Birzan et al. (2008) to show that the AGN is underpowered compared to the central X-ray cooling luminosity by roughly a factor of three. We suggest that A1664 is experiencing rapid cooling and star formation during a low-state of an AGN feedback cycle that regulates the rates of cooling and star formation. Modeling the emission as a single temperature plasma, we find that the metallicity peaks 100 kpc from the X-ray center, resulting in a central metallicity dip. However, a multi-temperature cooling flow model improves the fit to the X-ray emission and is able to recover the expected, centrally-peaked metallicity profile. Next, using deep Chandra observations of the Hydra A galaxy cluster, we examine the metallicity structure near the central galaxy and along its powerful radio source. We show that the metallicity of the ICM is enhanced by up to 0.2 dex along the radio jets and lobes compared to the metallicity of the undisturbed gas. The enhancements extend from a radius of 20 kpc from the central galaxy to a distance of ~120 kpc. We estimate the total iron mass that has been transported out of the central galaxy to be between 2E7 and 7E7 solar masses which represents 10% - 30% of the iron mass within the central galaxy. The energy required to lift this gas is roughly 1% to 5% of the total energetic output of the AGN. Evidently, Hydra A’s powerful radio source is able to redistribute metal-enriched, low entropy gas throughout the core of the galaxy cluster. The short re-enrichment timescale < 1E9 yr implies that the metals lost from the central galaxy will be quickly replenished. Finally, we present an analysis of the spatial distribution of metal-rich gas in 29 galaxy clusters using deep observations from the Chandra X-ray Observatory. The BCGs have experienced recent active galactic nucleus activity in the forms of bright radio emission, cavities, and shock fronts embedded in the hot atmospheres. The heavy elements are distributed anisotropically and are aligned with the large-scale radio and cavity axes. They are apparently being transported from the halo of the BCG into the ICM along large-scale outflows driven by the radio jets. The radial ranges of the metal-enriched outflows are found to scale with jet power as R ~ P^0.43, with a scatter of only 0.42 dex. The heavy elements are transported beyond the extent of the inner cavities in all clusters, suggesting this is a long lasting effect sustained over multiple generations of outbursts. Black holes in BCGs will likely have difficulty ejecting metal enriched gas beyond 1 Mpc unless their masses substantially exceed 1E9 solar masses. It is likely however for these black holes to output enough energy to uplift all the peaked, metal-rich gas beyond the BCG to the currently observed widespread distribution.
49

Secondary ion emission from single massive gold cluster impacts

Hager, George Joseph 17 September 2007 (has links)
Secondary ion mass spectrometry, SIMS, is one of the most versatile surface analytical techniques. The significant parameter determining the performance of SIMS is the secondary ion yield. Atomic projectiles, traditionally used in SIMS, are an inefficient method to desorb and generate secondary ions. The use of poly-atomic projectiles, such as (CsI)nCs, Au3, SF5 and C60, has been demonstrated to be an effective means to enhance secondary ion yields. Still larger secondary ion yields can be obtained with massive gold clusters, specifically Au4004+. Secondary ion yields from organic targets approach unity and are in excess of unity for selected inorganic targets. This dissertation is a first study of the secondary ion emission characteristics resulting from surface bombardment of keV Au400. The enhanced secondary ion yields from these massive clusters resulted in a need to detect isobaric secondary ions. An eight-anode detector was designed, built and implemented to study secondary ion emission resulting from massive projectile impacts. Secondary ion yield enhancements, resulting from use of the multi-anode detector, are reported along with secondary ion distributions for organic and inorganic targets. Au-adduct ions have been observed in mass spectra resulting form organic and inorganic targets bombarded by Au400. Data indicate that these adducts are a result of projectile/surface molecule interactions and not a product of Au implantation. Secondary ion yields of these adducts are reported. Although these adduct ion yields are an order of magnitude lower than the non-adduct ions, we have demonstrated their potential usefulness in analytical applications, such as examining surface homogeneity. Finally, these novel projectiles have been used to examine secondary ion emission from targets with different structural properties which have the same stoichiometry. In a comparative study, we have measured a significant difference in secondary ion emission and yields from the two systems, graphite and α-ZrP. Au400, at 136 keV, is effective in terms of secondary ion yield and secondary ion multiplicity enhancement. When used in the event-by-event bombardment/detection mode, the desorption volume has a diameter between 10-20 nm with and emission depth of approximately 5 nm, perturbing less than an attomole of analyte.
50

An economic assessment of the emerging renewable chemical and polymer cluster in Ohio with estimated economic impact on the state's economy

Ellis, Kathryn S., January 2009 (has links)
Thesis (M.S.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 117-125)

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