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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.
21

Forças regionais, formas urbanas e estrutura interna da cidade : um estudo de relações

Colusso, Izabele January 2015 (has links)
A busca pelo entendimento das transformações espaciais que são geradas diante do aumento do número de pessoas que vivem em cidades, do consequente aumento do espaço urbanizado, dos impactos na questão de consumo de espaço, e assim, das novas formas urbanas é assunto perseguido por diversas pesquisas. Nesta investigação, discutese a possibilidade de influência que o sistema regional pode ter sobre as formas urbanas que as cidades tendem a assumir. A diferença de escala envolvida nesta visão, que vai desde a escala regional, passa pela escala municipal, e chega à escala intraurbana, traz uma nova ótica no entendimento do paradoxo da estocástica dos modelos: que contradigam evidências empíricas porque sugerem que as cidades podem se desenvolver de forma independente. Colocada esta conjuntura que apresenta a maneira como hoje se aborda forma urbana, cidade e região, verifica-se que os estudos carecem de uma maior conexão e avaliação das influências entre as diferentes escalas e impactos. O encaminhamento desta pesquisa se dá através da proposta de um roteiro metodológico que envolve a medida de tensão regional, e verificações estatísticas e espaciais. Para esta verificação, foi utilizado o caso da região central do estado do Rio Grande do Sul, um sistema regional composto por 27 cidades, em 3 períodos de tempo, tornando possível a comparação das formas urbanas e seu respectivo crescimento e influência na estrutura interna das cidades. Os instrumentos desenvolvidos para obtenção de resultados nesta investigação fornecem uma ferramenta útil para estudar a influência do efeitos espaciais sobre a agregação de modelos de interação espacial e o quanto podem contribuir de diversas maneiras para realizações substanciais em estudos econométricos espaciais, além de que sugerem ferramentas estatísticas que inferem o valor, intensidade e hierarquia provável de fluxos médios a certos níveis de agregação de variáveis disponíveis reais e estimadas. As possibilidades de visualização e comparação da repercussão entre diferentes escalas espaciais permite assim relacionar escalas regionais, municipais e intraurbanas, e constata-se que existe grande influência da escala regional sobre as alterações da estrutura interna da cidade. / The search for understanding the spatial transformations that are generated by the increase in the number of people living in cities, the resulting increase in urbanized space, impacts on the issue of space consumption, and thus, new urban forms, is a subject pursued by several researches. In this investigation, we discuss the possible influence that the regional system can have on urban forms that cities tend to assume. The difference of scale involved in this vision, ranging from regional, passes through the municipal scale, and comes to the intraurban scale, brings a new light on the paradox of understanding the stochastic models: that they contradict empirical evidence, because they suggest that cities can develop independently from each other and from the region where they are inserted. Placed this scenario that shows how today are addressed urban form, cities and regions, it appears that is required further studies and evaluation of connection between the different scales influences and impacts. The forwarding of this research is through the proposal of a methodological plan that involves regional tension measurement, and statistics and spatial verification. To check this, we used the case of the central region of the state of Rio Grande do Sul, a regional system composed by 27 cities in three periods of time, making it possible to compare the urban forms and their respective growth and influence in the internal structure of the cities. The instruments developed to achieve results in this study provide a useful tool for studying the influence of spatial effects on the aggregation of spatial interaction models and how much they can contribute in several ways to substantial achievements in spatial econometric studies, and suggest that statistical tools to infer the value, intensity and probable hierarchy of average flows at certain levels of aggregation of real variables available and estimated. The display options and comparison of the impact of different spatial scales makes it possible to relate regional, municipal and intra-urban scale, and it appears that there is a great influence on regional scale changes in the internal structure of the city.
22

Forças regionais, formas urbanas e estrutura interna da cidade : um estudo de relações

Colusso, Izabele January 2015 (has links)
A busca pelo entendimento das transformações espaciais que são geradas diante do aumento do número de pessoas que vivem em cidades, do consequente aumento do espaço urbanizado, dos impactos na questão de consumo de espaço, e assim, das novas formas urbanas é assunto perseguido por diversas pesquisas. Nesta investigação, discutese a possibilidade de influência que o sistema regional pode ter sobre as formas urbanas que as cidades tendem a assumir. A diferença de escala envolvida nesta visão, que vai desde a escala regional, passa pela escala municipal, e chega à escala intraurbana, traz uma nova ótica no entendimento do paradoxo da estocástica dos modelos: que contradigam evidências empíricas porque sugerem que as cidades podem se desenvolver de forma independente. Colocada esta conjuntura que apresenta a maneira como hoje se aborda forma urbana, cidade e região, verifica-se que os estudos carecem de uma maior conexão e avaliação das influências entre as diferentes escalas e impactos. O encaminhamento desta pesquisa se dá através da proposta de um roteiro metodológico que envolve a medida de tensão regional, e verificações estatísticas e espaciais. Para esta verificação, foi utilizado o caso da região central do estado do Rio Grande do Sul, um sistema regional composto por 27 cidades, em 3 períodos de tempo, tornando possível a comparação das formas urbanas e seu respectivo crescimento e influência na estrutura interna das cidades. Os instrumentos desenvolvidos para obtenção de resultados nesta investigação fornecem uma ferramenta útil para estudar a influência do efeitos espaciais sobre a agregação de modelos de interação espacial e o quanto podem contribuir de diversas maneiras para realizações substanciais em estudos econométricos espaciais, além de que sugerem ferramentas estatísticas que inferem o valor, intensidade e hierarquia provável de fluxos médios a certos níveis de agregação de variáveis disponíveis reais e estimadas. As possibilidades de visualização e comparação da repercussão entre diferentes escalas espaciais permite assim relacionar escalas regionais, municipais e intraurbanas, e constata-se que existe grande influência da escala regional sobre as alterações da estrutura interna da cidade. / The search for understanding the spatial transformations that are generated by the increase in the number of people living in cities, the resulting increase in urbanized space, impacts on the issue of space consumption, and thus, new urban forms, is a subject pursued by several researches. In this investigation, we discuss the possible influence that the regional system can have on urban forms that cities tend to assume. The difference of scale involved in this vision, ranging from regional, passes through the municipal scale, and comes to the intraurban scale, brings a new light on the paradox of understanding the stochastic models: that they contradict empirical evidence, because they suggest that cities can develop independently from each other and from the region where they are inserted. Placed this scenario that shows how today are addressed urban form, cities and regions, it appears that is required further studies and evaluation of connection between the different scales influences and impacts. The forwarding of this research is through the proposal of a methodological plan that involves regional tension measurement, and statistics and spatial verification. To check this, we used the case of the central region of the state of Rio Grande do Sul, a regional system composed by 27 cities in three periods of time, making it possible to compare the urban forms and their respective growth and influence in the internal structure of the cities. The instruments developed to achieve results in this study provide a useful tool for studying the influence of spatial effects on the aggregation of spatial interaction models and how much they can contribute in several ways to substantial achievements in spatial econometric studies, and suggest that statistical tools to infer the value, intensity and probable hierarchy of average flows at certain levels of aggregation of real variables available and estimated. The display options and comparison of the impact of different spatial scales makes it possible to relate regional, municipal and intra-urban scale, and it appears that there is a great influence on regional scale changes in the internal structure of the city.
23

Intellektuellt Kapital : Medelstora företags rapportering av intellektuellt kapital / Intellectual capital : MidCap companies reporting of intellectual capital

Ahlfridh, Philip, Nordström, Ebba January 2020 (has links)
Tidigare forskning har endast fokuserats på företag med begränsningen LargeCap och i denna studie studerar vi vad medelstora företag rapporterar om intellektuellt kapital. Studiens resultat visar på ett liknande trendmönster med tidigare studier som enbart har analyserat LargeCap företag.   Syftet med studien är att undersöka vad medelstora företag rapporterar om intellektuellt kapital, med insamlad data från svenska börsnoterade företag. För att bemöta syftet har litteratur från tidigare forskning och empiriska data från urvalsföretagens årsredovisningar för 2014 samt 2018 använts. Till följd av detta kunde en frågeställning skapas: vilka delar av intellektuellt kapital är det börsnoterade företag redovisar?   Studien visar på att MidCap företag följer samma trend i rapporteringen av intellektuellt kapital som LargeCap företag. Resultatet visar dock på en lägre frekvens av rapporteringen i MidCap företag jämfört med tidigare studier om LargeCap företag.   Studien har bidragit till ett nytt teoretiskt perspektiv för att illustrera företags rapportering av intellektuellt kapital. Studien har bidragit till att skiljaktigheten i företagens rapportering inte är beroende av storleken för att bedöma ett rapporteringsmönster. Ett empiriskt bidrag är att studien har tillfört en ny tillämpningsgrupp i en befintlig teori och det praktiska bidraget är att intressenter informeras om vilka delar företag rapporterar om intellektuellt kapital samt hur företag kan använda denna studie till att anpassa rapporteringen av intellektuellt kapital. / Previous research has solely been focusing on companies with the restriction LargeCap and in this study we have studied what MidCap companies report regarding intellectual capital. The study results show a similar pattern with previous studies that has only analysed LargeCap.   The purpose of this study is to examine what MidCap companies reports about intellectual capital, with collected data from Swedish listed companies. To meet the purpose has literature from previous research and empirical data from the sampled companies' annual reports from 2014 and 2018 been used. Due to this could an issue be established: which parts of intellectual capital are the listed companies reporting?   The study of MidCap companies follows the same pattern in the reporting of intellectual capital as LargeCap companies. However, the result shows a lower frequency of reports in MidCap companies in relation to previous research about LargeCap companies.   The study has contributed to a new theoretical perspective to illustrate companies reporting regarding intellectual capital. The research has contributed to differences in companies reporting are not dependent on the size to assess a reporting pattern. An empirical contribution is that the study has brought a new sample group for an existing theory and the practical contribution is that the stakeholders are getting informed which parts of intellectual capital companies are reporting and also how companies can utilize this study to adjust their reporting of intellectual capital.
24

Avalanching on dunes and its effects : size statistics, stratification, & seismic surveys

Arran, Matthew Iain January 2018 (has links)
Geophysical research has long been interdisciplinary, with many phenomena on the Earth's surface involving multiple, linked processes that are best understood using a combination of techniques. This is particularly true in the case of grain flows on sand dunes, in which the sedimentary stratification with which geologists are concerned arises from the granular processes investigated by physicists and engineers, and the water permeation that interests hydrologists and soil scientists determines the seismic velocities of concern to exploration geophysicists. In this dissertation, I describe four projects conducted for the degree of Doctor of Philosophy, using a combination of laboratory experimentation, fieldwork, numerical simulation, and mathematical modelling to link avalanching on dunes to its effects on stratification, on the permeation of water, and on seismic surveys. Firstly, I describe experiments on erodible, unbounded, grain piles in a channel, slowly supplied with additional grains, and I demonstrate that the behaviour of the consequent, discrete avalanches alternates between two regimes, typified by their size statistics. Reconciling the `self-organised criticality' that several authors have predicted for such a system with the hysteretic behaviour that others have observed, the system exhibits quasi-periodic, system-spanning avalanches in one regime, while in the other avalanches pass at irregular intervals and have a power-law size distribution. Secondly, I link this power-law size distribution to the strata emplaced by avalanches on bounded grain piles. A low inflow rate of grains into an experimental channel develops a pile, composed of strata in which blue-dyed, coarser grains overlie finer grains. Associating stopped avalanche fronts with the `trapped kinks' described by previous authors, I show that, in sufficiently large grain piles, mean stratum width increases linearly with distance downslope. This implies the possibility of interpreting paleodune height from the strata of aeolian sandstones, and makes predictions for the structure of avalanche-associated strata within active dunes. Thirdly, I discuss investigations of these strata within active, Qatari barchan dunes, using dye-infiltration to image strata in the field and extracting samples across individual strata with sub-centimetre resolution. Downslope increases in mean stratum width are evident, while measurements of particle size distributions demonstrate preferential permeation of water along substrata composed of finer particles, explaining the strata-associated, localised regions of high water content discovered by other work on the same dunes. Finally, I consider the effect of these within-dune variations in water content on seismic surveys for oil and gas. Having used high performance computing to simulate elastic wave propagation in the vicinity of an isolated, barchan sand dune, I demonstrate that such a dune acts as a resonator, absorbing energy from Rayleigh waves and reemitting it over an extensive period of time. I derive and validate a mathematical framework that uses bulk properties of the dune to predict quantitative properties of the emitted waves, and I demonstrate the importance of internal variations in seismic velocity, resulting from variations in water content.
25

Propriétés mécaniques, structure interne et mécanismes de transfert de l'oxygène dans le liège / Mechanical properties, internal structure and transport mechanism of oxygen in cork

Lagorce-Tachon, Aurélie 10 December 2015 (has links)
Lors de la conservation des vins en bouteilles, des réactions d’oxydation prématurées peuvent se produire et les propriétés barrières à l’oxygène de l’obturateur en liège sont souvent mises en cause. À l’heure actuelle, aucune étude n’a permis de déterminer la structure interne du liège ou l’effet de l’hydratation sur ses propriétés mécaniques. Quant aux propriétés barrières à l’oxygène, l’étape limitante au transfert reste indéterminée ainsi que l’effet de la compression et le rôle de l’interface verre/liège. L’étude de la structure interne du liège par imagerie a permis de visualiser la macroporosité du matériau et de conclure que pour les qualités de liège étudiées, les lenticelles ne sont pas interconnectées. La caractérisation des propriétés mécaniques du liège a montré que le module de Young n’était pas affecté pour une humidité relative < 50 %. En milieu plus humide, ce dernier diminue à cause de la formation de clusters de molécules d’eau entre les chaines de polymères constituants les parois cellulaires. En comparant le comportement du liège brut avec celui d’autres obturateurs, un effet de la taille des particules de liège et du ratio liège/additifs utilisés dans ces obturateurs, a également été mis en évidence. Au regard du mécanisme de transfert de gaz, les mécanismes en jeu et en particulier l’étape limitante ont été clairement déterminés : il s’agit de la diffusion au travers des parois cellulaires selon la loi de Fick. L’effet de la compression du bouchon ne modifie pas significativement le transfert d’oxygène tandis que le rôle de l’interface verre/liège semble gouverner les transferts de gaz de l’extérieur vers l’intérieur de la bouteille. / During the post bottling aging, premature oxidation reactions could occur and the oxygen barrier properties of the stopper are often pointed out. Nowadays, the internal structure of this material or the effect of hydration on its mechanical properties are still undetermined. Moreover, regarding the barrier properties, the limiting step of the oxygen transfer was not yet fully understood as well as the effect of compression or the role of the glass/cork interface in a bottleneck. The study of the internal structure of cork stopper allowed us to visualize the macroporosity of the material and conclude that there is no interconnectivity between lenticels, for the two qualities studied. The effect of hydration on the mechanical properties of cork was also investigated. The results shown that the rigidity of the material was not significantly affected for relative humidity < 50 %. Above this hydration level, the Young’s moduli decrease due to clusters formation of water molecules. Comparing the natural cork behavior to other stoppers, an effect of the particle size and the ratio cork/additives used in these stoppers was also highlighted. Regarding the transport mechanism of gas through cork, the limiting step was clearly determined: it’s the diffusion through the cell wall according to a Fickian mechanism. The compression of the stopper does not have a significant impact on the effective diffusion coefficient of oxygen. However, the role of the glass/cork interface is really important and seems to govern the gas transfer from the surrounding atmosphere into the bottle.
26

Propiedades psicométricas de la Gender Role Conflict Scale en varones trabajadores del sector de comunicaciones de Lima Metropolitana / Psychometric properties of the Gender Role Conflict Scale in working men of the communications sector of Metropolitan Lima

Chávarri Cafferata, Mariel Alejandra, Lamas Nuñovero, Andrea 30 July 2020 (has links)
El objetivo de la investigación fue determinar las propiedades psicométricas de la Gender Role Conflict Scale (GRCS) en varones que trabajan en el sector de comunicación en Lima Metropolitana. La muestra estuvo conformada por 337 varones, cuyo rango de edad oscila entre 23 a 58 años (M =34.00, DE = 9.39). Los instrumentos aplicados fueron la GRCS y la Escala de Pensamientos Patriarcales (EPP). En la validez basada en la estructura interna se comprobó el modelo de cuatro factores relacionados, mostrando un buen ajuste (χ²/gl = 2.06, CFI = .86 y, RMSEA = .06).  En la validez basada en relaciones con otras variables, entre los factores de la GRCS se obtuvo correlaciones altas y moderadas (valores de Pearson entre .24 y .78) y con las dimensiones de la EPP arrojó correlaciones bajas y moderadas (valores de Spearman entre .10. y .39). Los resultados del análisis de confiabilidad por consistencia interna indicaron coeficientes Omega (>.70) adecuados por cada dimensión. En general, la GRS posee adecuadas propiedades psicométricas. / The objective of the research was to determine the psychometric properties of the Gender Role Conflict Scale (GRCS) in men who work in the communication sector in Metropolitan Lima. The sample was made up of 337 men, whose age range ranged from 23 to 58 years (M = 34.00, SD = 9.39). The instruments applied were the GRCS and the Scale of Patriarchal Thoughts (EPP). In the validity based on the internal structure, the four-factor model was tested, showing a good fit (χ² / gl = 2.06, CFI = .86 and, RMSEA = .06). In the validity based on relationships with other variables, between the GRCS factors it obtained high and moderate correlations (Pearson values ​​between .24 and .78) and with the dimensions of the EPP it produced low and moderate correlations (Spearman values ​​between. 10. and .39). The results of the internal consistency reliability analysis indicated by dimension an adequate Omega coefficient (> .70) in the scale and its dimensions. In general, the GRCS has adequate psychometric properties. / Tesis
27

Mesure de la section efficace d'électroproduction de photons sur le neutron à Jefferson Lab en vue de la séparation du terme de diffusion Compton profondément virtuelle / Measurement of the photon electroproduction cross section off the neutron at Jefferson Lab in view of the separation of the deeply virtual Compton scattering term

Desnault, Camille 17 September 2015 (has links)
La section efficace d'électroproduction de photons sur le nucléon est proportionnelle aux amplitudes au carré de diffusion Compton profondément virtuelle (DVCS) et du Bethe-Heitler ainsi qu'un terme d'interférence de ces deux processus. Sa mesure sur le neutron fut réalisée dans le cadre de l'expérience E08-025 qui s'est déroulée en 2010 dans le Hall A à Jefferson Lab (USA). Par une forte sensibilité au terme d'interférence, elle aura permis l'extraction de trois observables dépendantes des Distributions Généralisées de Partons (GPDs), ainsi que la perspective de séparer par une méthode Rosenbluth le terme |DVCS|².Les GPDs sont des fonctions de structure qui nous permettent de comprendre la structure interne des nucléons en terme de corrélation entre les distributions en position transverse et en impulsion longitudinale des quarks au sein du nucléon. Plus qu'un moyen d'accéder à une image tri-dimensionnelle de la composition élémentaire du nucléon, la détermination des GPDs du neutron permettrait par la règle de somme de Ji l'accès au moment angulaire des quarks dans le nucléon, la pièce manquante à la compréhension du mystère lié au spin du nucléon.Cette thèse aborde le contexte théorique de la mesure de la section efficace d'électroproduction de photons sur le neutron, puis une description de la configuration expérimentale utilisée pour sa réalisation. Elle expose la sélection des données d'intérêt pour cette mesure et présente les résultats obtenus par une méthode d'ajustement des données à une simulation Monte Carlo dont la démarche est expliquée en détails. Pour finir, une étude systématique des résultats achève ce manuscrit. / The photon electroproduction cross section off the nucleon is proportional to the deeply virtual Compton scattering (DVCS) and Bethe-Heitler amplitudes squared together with an interference term between these two processes. Its measurement on the neutron has been performed in the framework of the E08-025 experiment which took place in 2010 in Hall A at Jefferson Lab (USA). Thanks to a high sensibility to the interference term, it made possible the extraction of three Generalized Parton Distributions (GPDs) dependent observables, as well as the prospect to extract the |DVCS|² term through a Rosenbluth separation.The GPDs are structure functions which allow to understand the internal structure of nucleons in term of the correlation between transverse spatial and longitudinal momentum distributions of quarks inside the nucleon. More than a way to access a three-dimensional picture of the elementary arrangement of the nucleon, the measurement of GPDs on the neutron would give access by the Ji's sum rule to the angular momentum of quarks in the nucleon, the missing piece for the understanding of the nucleon spin puzzle.This thesis outlines the theoretical context of the measurement of the photon electroproduction cross section off the neutron, and the experimental setup used for its achievement. It describes the selection of the experimental data of interest for this measurement and presents the results obtained from a fitting method of data to a Monte Carlo simulation, which is explained in detail. Finally, a systematic study of the results completes this manuscript.
28

Physicochemical and rheological properties of interacted protein hydrolysates derived from tuna processing by-products with sodium alginate

Gao, Jingrong, He, Shan, Nag, Anindya, Zeng, Xin-An 04 April 2024 (has links)
The physicochemical properties of tuna protein hydrolysates were enhanced by interaction with sodium alginate. The increase in emulsifying capacity and stability was from 50 to 150 m² g⁻¹ and from 36 to 49 min, respectively. The increase in foaming capacity and stability was from 100% to 140% and from 65% to 70%, respectively. The reason for the increased physicochemical properties was the reduced zeta potential level of tuna protein hydrolysates after interaction with sodium alginate. The change in internal structure of tuna protein hydrolysates after interaction with sodium alginate was determined by SEM and FTIR. The SEM results showed that a net cross-linking structure was formed from a sheet structure after the tuna protein hydrolysates interacted with sodium alginate. FTIR demonstrated that parts of the β-sheet of tuna protein hydrolysates were changed into an irregular coiled structure or α-helix after interaction with sodium alginate. In order to understand the interacted complex better, the rheological properties of interacted tuna protein hydrolysates with sodium alginate were further determined. In this study, the one-step was developed, easy-to-operate and cost-effective process that can further add value to tuna protein hydrolysates derived from tuna processing by-products.

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