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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.
171

Infiltração da água em latossolo vermelho distroférrico utilizando infiltrômetros de cilíndro único / Water infiltration in dystropheric red latosol using single cylinder infiltrometers

Frigo, Jianice Pires 19 April 2017 (has links)
Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2017-09-05T12:35:02Z No. of bitstreams: 1 Jianice_Frigo2017.pdf: 1119086 bytes, checksum: 87f159fe89d2840c9e6c7be155e2a65c (MD5) / Made available in DSpace on 2017-09-05T12:35:02Z (GMT). No. of bitstreams: 1 Jianice_Frigo2017.pdf: 1119086 bytes, checksum: 87f159fe89d2840c9e6c7be155e2a65c (MD5) Previous issue date: 2017-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The infiltration process understanding and its relationship with soil properties is essential for the efficient management of soil and water. Thus, this paper aimed at evaluating water infiltration in an area of Oxisol, using single ring infiltrometers with different diameters. In addition, it also aimed at comparing the performance of 7 cm (A7) and 15 cm (A15) cylinders, matching soil moisture and bulk density to water infiltration and evaluating spatial distribution of infiltration. For this purpose, 24 data points were evaluated, placed in 8 plots of a circular area prepared for permaculture cropping, named as Mandala. Shewhart graphs and process capability index were used to compare cylinders and the inverse of distance square for data interpolation. It was observed that the average stable infiltration rate, determined with A7 cylinder, was 196.79 mm h-1 and with A15 cylinder was 187.30 mm h-1, consequently, there was a difference of 5.6%. The process capacity was estimated at 0.61 for A7 and 1.62 for A15, considered adequate for A15 and inadequate for A7 cylinder. Thus, it was concluded that the infiltration rates that were stabilized and determined by the cylinders were compatible with the rates determined by other methods in other papers. Regarding the performance of single-ring infiltrometers, it is concluded that, although both cylinders presented controlled processes, and did not differ statistically, cylinder A15 presented less variability on data, and may be considered adequate due to its process capability index. / O entendimento do processo de infiltração e das suas relações com as propriedades do solo é fundamental para o eficiente manejo do solo e da água. Assim, este trabalho teve como objetivo avaliar a infiltração de água em uma área de latossolo vermelho, para tanto, foram utilizados infiltrômetros de único cilindro, de diferentes diâmetros. Além disso, objetivou-se comparar o desempenho desses cilindros de 7 (A7) e de 15 cm (A15), relacionar a umidade e a densidade aparente do solo à infiltração da água e avaliar a distribuição espacial da infiltração. Foram avaliados 24 pontos de coleta de dados, alocados em 8 parcelas de um talhão circular preparado para plantio em regime de permacultura, denominado mandala. Gráficos de Shewhart e o índice de capacidade de processo foram utilizados para a comparação entre os cilindros e inverso do quadrado da distância para interpolação de dados. Verificou-se que a taxa de infiltração estável média, determinada com o cilindro A7, foi de 196,79 mm h-1 e com o cilindro A15 foi de 187,30 mm h-1, cuja diferença foi de 5,6 %. A capacidade de processo foi estimada em 0,61 para A7 e 1,62 para A15, a qual foi considerada adequada para o cilindro A15, porém inadequada para cilindro A7. Desta forma, neste trabalho, concluiu-se que as taxas de infiltração estáveis e determinadas pelos cilindros foram compatíveis com as taxas determinadas por outros métodos em outros trabalhos. Em relação ao desempenho dos infiltrômetros de cilindros únicos, conclui-se que, embora ambos os cilindros tenham apresentado processos controlados e não tenham diferido estatisticamente, o cilindro A15 apresentou menos variabilidade dos dados, e pode ser considerado adequado em função do seu índice de capacidade de processo.
172

Modellierung und Bewertung von Maßnahmen zur Schaffung einer Stadt der kurzen Wege

Hübner, Susan 27 April 2017 (has links) (PDF)
Urban Sprawl, d. h. die exzessive Ausdehnung städtischer Fläche erzeugt sowohl aus ökonomischer, ökologischer und sozialer als auch aus verkehrlicher Sicht negative Wirkungen für Mensch und Umwelt und stellt damit ein ernst zu nehmendes Problem im urbanen Kontext dar. Diese Entwicklung ist einerseits auf natürliche Ursachen wie Bevölkerungswachstum, Präferenzen der Haushalte und die fallenden Transportkosten zurückzuführen. Andererseits treiben aber auch bestehende Marktverzerrungen wie die Subventionierung suburbaner Infrastrukturen, die fehlende Einbeziehung des Nutzens von freier Fläche und im Speziellen die Nicht-Berücksichtigung der externen Kosten des Verkehrs das städtische Wachstum über das optimale Maß hinaus voran. Im Zentrum der vorliegenden Arbeit steht daher das Konzept einer Stadt der kurzen Wege, das eine Möglichkeit darstellt, diesen Problemen zu begegnen. Ziel ist es dabei, mit Hilfe von Verdichtung und Nutzungsmischung innerhalb urbaner Strukturen die Verlagerung und Vermeidung von Verkehr zu erreichen und die zurückgelegten Distanzen insgesamt zu senken. Um die Wirksamkeit dieses Konzeptes besser beurteilen zu können, untersucht die vorliegende Arbeit die folgenden Fragestellungen: • Wie kann eine Stadt der kurzen Wege definiert werden? Welche Merkmale besitzt sie, welche Wirkungen erzeugt sie und wie können diese gemessen werden? • Wie kann eine Stadt der kurzen Wege umgesetzt werden? Welche Strategie wird dazu verfolgt und welche Maßnahmen stehen zur Verfügung? • Inwieweit tragen ausgewählte Maßnahmen zur Schaffung einer Stadt der kurzen Wege bei? Wie wirken sie und welche Rolle spielt ihre Ausgestaltung?
173

Contribution à l'indicateur de Hicks-Moorsteen et à la théorie de la productivité. / A contrivution to the Hicks-Moorsteen index and productivity theory

Stenger, Agathe 04 June 2015 (has links)
Ce travail contribue à la définition des mesures de l'efficacité et de la productivité dans la théorie microéconomique. Il présente des apports théoriques et empiriques. En premier lieu, cette thèse élabore une critique sur certaines mesures classiques de l’efficacité et de la productivité. Il est montré que la mesure directionnelle, sous l'hypothèse de rendements d'échelle constants, pose un certain nombre de problèmes quant à l’évaluation des variations de la productivité. De plus, il est établi que la « slacks-based » et la directionnelle « slack-based » mesures (ou mesures de Färe-Lovell) ne permettent pas de caractériser la technologie de production. Il résulte que ce type de mesure ne permet pas d’évaluer l'efficacité et les variations de productivité. Une approche alternative est proposée qui permet de contourner cette difficulté. Ensuite, cette thèse introduit deux nouveaux indicateurs: un indicateur social de Luenberger-Hicks-Moorsteen et un indicateur de productivité généralisé. Le premier permet d'évaluer l'effet des politiques sur les capabilités au sens d'A. Sen. Il consiste en une transposition des indicateurs de Hicks-Moorsteen en considérant le rôle spécifique d’un sous-vecteur prenant en compte les facteurs sociaux. Le second indicateur généralise les indicateurs standards de productivité. Il permet de retrouver à la fois les indicateurs de Luenberger et le Luenberger Hicks-Moortsteen comme cas spéciaux de cet indicateur généralisé. En considérant la version multiplicative de l’indicateur généralisé, on retrouve comme cas particuliers, les indicateurs de Malmquist et le Hicks-Moorsteen. Enfin, cette thèse présente des applications empiriques qui illustrent la méthodologie. Ces études évaluent et comparent la performance des régions touristiques et plus précisément celle du Languedoc-Roussillon, qui mobilise un cadre d'analyse transfrontalier. / This phd contributes to the definition of efficiency measures and productivity indicator, in the microeconomic theory. It presents theoretical and empirical contributions. Firstly, this phd develops a review on standard measures of efficiency and productivity. It is shown that the directional measure, under the assumption of constant returns to scale, raises some problems in the assessment of productivity changes. Moreover, it is established that the "slacks-based" and directional "slack-based" measures (or Färe-Lovell measures) do not allow to characterize technology. It follows that such measures do not allow to evaluate efficiency and productivity changes. An alternative approach is proposed which overcomes this difficulty. Then, this phd introduces two new indicators: a social Luenberger-Hicks-Moorsteen indicator and a generalized indicator of productivity. The first mesure the impact of publics policies in the line of the capability theory introduce by A. Sen. This indicator consists on a transposition of the Hicks-Moorsteen indicator by considering a sub-vector of social factors. The second indicator generalizes standards productivity indicators. It allows to find the Luenberger and the Luenberger Hicks-Moortsteen as special cases of this general indicator. Considering the multiplicative version of the generalized indicator, on can find the Malmquist and Hicks-Moorsteen indicators, as special cases. Finally, this phd presents some empirical applications to illustrate the methodology. These studies evaluate and compare the performance of the tourist destination, and specifically for the Languedoc-Roussillon, which involves a cross-border analysis framework
174

Vliv vrubů při cyklickém vysokofrekvenčním únavovém zatěžování / Influence of notches under cyclic high-frequency fatigue loading

Kozáková, Kamila January 2021 (has links)
The diploma thesis deals with the evaluation of the lifetimes of smooth and notched specimens. The comparison of their lifetimes is focused on the case of high-frequency cyclic loading in the area of high-cycle and gigacycle fatigue of materials. The theory of critical distances is used to evaluate and recalculate the life curves of the notched specimens. The effect of the notch is quantified using the Line method. The critical length parameter is determined so that the life curve of the notched specimens corresponds to the curve measured on smooth specimens. The result is the dependence of the critical length parameter on the number of cycles to fracture. Knowledge of critical length parameters can be used to determine the lifetime of notched specimens as well as real notched components using the results of fatigue tests of smooth specimens.
175

Městský dům - architektura kombinace funkcí / City House – Mixet Use Architecture

Starý, Ondřej January 2013 (has links)
The main goal of the project is to design a city house near the central part of Brno as an alternative for the existing monofunctional zones and finding out the most suitable functions for the area. The idea is based on a compact city block which communicates with the events on the streets and connects them together to the house via inner atrium. Within the intensive urban structure, housing was chosen for the most important component because nowadays it disappears from the city centres. As the prerequisite for the high-quality living, the residential floors were raised on a three-storey platform which integrates the culture, offices and the commercial use. The roof of the platform is also used as a green roof terrace with a lot of vegetation which protects the living against the polution and noise from the traffic. So it becomes a safe and calm place for the relaxation and children´s games in a busy part of the city. The important point of view where the emphasis was placed was connecting all the functions together not only within the house itself, but also within the range of the whole city. The house functions and the street area are mutually connected via inner public atrium which becomes the important people meeting site. The residential floors are connected to the rest of the house through the large roof skylight which allows the sun rays to reach the lower floors. So the city house doesn´t hide its purpose on its own, but rather "lives together with the city".
176

Zvýšení konkurenceschopnosti železniční osobní dopravy v úseku Uničov - Šumperk / Competitiveness Improvements of Railway Passenger Transport in Section Unicov - Sumperk

Melecký, Martin January 2017 (has links)
The thesis target is to design construction treatments resulting in improving the passenger railway transport in this section. Planned modernization and electrification will change the transport nature significantly, which calls for an examination of the existing track possibilities. The task was to focus on the regarding stations as a crucial troughput aspect and on the travel quality improvment by minor construction adjustments. I have examined walking distances, designed a new Troubelice - Centrum stop. By convenient platform shifts higher velocities criteria were met. All precautions respect the wheelchair access. The station design allows higher velocities operation and do not restricts current use.
177

Modellierung und Bewertung von Maßnahmen zur Schaffung einer Stadt der kurzen Wege

Hübner, Susan 18 February 2016 (has links)
Urban Sprawl, d. h. die exzessive Ausdehnung städtischer Fläche erzeugt sowohl aus ökonomischer, ökologischer und sozialer als auch aus verkehrlicher Sicht negative Wirkungen für Mensch und Umwelt und stellt damit ein ernst zu nehmendes Problem im urbanen Kontext dar. Diese Entwicklung ist einerseits auf natürliche Ursachen wie Bevölkerungswachstum, Präferenzen der Haushalte und die fallenden Transportkosten zurückzuführen. Andererseits treiben aber auch bestehende Marktverzerrungen wie die Subventionierung suburbaner Infrastrukturen, die fehlende Einbeziehung des Nutzens von freier Fläche und im Speziellen die Nicht-Berücksichtigung der externen Kosten des Verkehrs das städtische Wachstum über das optimale Maß hinaus voran. Im Zentrum der vorliegenden Arbeit steht daher das Konzept einer Stadt der kurzen Wege, das eine Möglichkeit darstellt, diesen Problemen zu begegnen. Ziel ist es dabei, mit Hilfe von Verdichtung und Nutzungsmischung innerhalb urbaner Strukturen die Verlagerung und Vermeidung von Verkehr zu erreichen und die zurückgelegten Distanzen insgesamt zu senken. Um die Wirksamkeit dieses Konzeptes besser beurteilen zu können, untersucht die vorliegende Arbeit die folgenden Fragestellungen: • Wie kann eine Stadt der kurzen Wege definiert werden? Welche Merkmale besitzt sie, welche Wirkungen erzeugt sie und wie können diese gemessen werden? • Wie kann eine Stadt der kurzen Wege umgesetzt werden? Welche Strategie wird dazu verfolgt und welche Maßnahmen stehen zur Verfügung? • Inwieweit tragen ausgewählte Maßnahmen zur Schaffung einer Stadt der kurzen Wege bei? Wie wirken sie und welche Rolle spielt ihre Ausgestaltung?
178

Galaxy populations in distant, X-ray selected clusters of galaxies

Trudeau, Ariane 19 August 2022 (has links)
Galaxy clusters are the largest gravitationally bound structures in the Universe. Their masses are dominated by dark matter ($\sim$85\% of the mass) with stars representing 1-4\% of their masses. A hot, X-ray emitting gas called the intracluster medium makes most of their baryonic mass. The presence of this gas and of numerous neighbouring galaxies prematurely stop the star formation in clusters. In other terms, more galaxies in clusters are passive than in the general population of galaxies. This effect is mass and position-dependant: high-mass galaxies are more likely to be passive than less massive ones; galaxies inhabiting the cluster core are also less likely to form stars than those in the outskirts. The fraction of passive galaxies is greater in local clusters than in high-redshift ones, because they had more time to evolve. Much is unknown about the cessation of star formation, called quenching, in clusters. Thus, although many examples of infalling galaxies being stripped of their gas have been reported for low-mass galaxies, it is unclear if the most massive members became quenched before or after they become cluster members. The relationship between quenching and the cluster mass is also poorly understood. Despite the variety of methods devised to find clusters of galaxies, most of what we know about quenching in $z\gtrsim 1$ clusters was discovered with optically/infrared-selected cluster samples (clusters found as overdensities of galaxies), or samples of mixed origin. Yet, there is tentative evidence that optically/infrared-selected samples are biased toward having more passive galaxies than those that were X-ray selected. In the present dissertation, quenching is explored in X-ray selected cluster samples. A sample of high-redshift, low-mass galaxy clusters is built by finding galaxy overdensities coincident with sources of extended X-ray emission. A photometry-based analysis reveals that the fraction of quenched galaxies in these clusters is very variable. Moreover, the brightest cluster galaxies are also diverse. Yet, for all the information that photometry can provide, this sample candidate clusters need to be confirmed with spectroscopy. Spectroscopic observations obtained for four candidate clusters are reduced and analysed. The results show that three of them are clusters, the fourth candidate being a superposition of structures. Member spectra are examined to infer their star formation history, and the results shows the existence of an intermediary population of galaxies, where an old stellar population coexists with weak star formation. Finally, the galaxies of a $z=1.98$ X-ray selected cluster, XLSSC 122 are investigated in detail. Photometric data in 12 bands are organized to perform spectral energy distribution fittings, a technique that allows a simplified reconstitution of the history of the star formation. Results show that the members were formed at diverse epochs, the oldest being about 2.5 Gyrs old. Simulations drawn from the Multi Dark Planck 2 are used to infer the mass-scale of the cluster when the oldest galaxies were formed, something that has never been done before. The oldest galaxies were probably formed when XLSSC 122 had accreted $<$10\% of its $z=1.98$ mass, i.e. the mass-scale of a galaxy group. / Graduate
179

Mapping Business Model Success Factors in Low Populated Developing Areas - A Minor Field Study in Northern Namibia with Focus on Agricultural Technology / Kartläggning av framgångsfaktorer för affärsmodeller i lågbefolkade utvecklingsområden - En fältstudie i norra Namibia med fokus på lantbruksteknik

Canclini, Sofia, Liang, Victor January 2018 (has links)
Namibia has the third lowest population density in the world and a large part of the population are dependent on small-scale subsistence farming for survival. What was found during the study is that large distances between communities has created challenges in terms of infrastructure, logistics and communication. These factors needsto be taken into consideration when conducting or starting business. This research examined success factors in existing business initiatives by and for rural farmers in northern Namibia with focus on the implementation of new technology that supports everyday work. Previous literature shows that the best way to implement and startbusiness in scarcely populated areas has not eectively been addressed. The purpose of this study is to gain a general understanding of the context and identify business model success. An eight-week eld study was performed in Namibia during spring of2018. Empirical data was gathered through qualitative interviews and workshops with farmers and business initiative takers that focus on the cultivation and processing of the staple grain mahangu. The main ndings from the research is that more businesses are forming in these rural areas and farmers are slowly adapting to the benets thatnew technology entails, although, full acceptance of new tools is slower due to the long distances, low income, and deeply rooted traditions. A major success-factor is to increase availability through small-scale empowerment of many farmers. Having many smaller businesses in a large area will increase the availability which in turn will lead to increased spread and adaption of technology. The long term benets of new businesses can support the development of the country and also increase quality of life for rural people. It was also identied that a large part of the population conduct business on the informal markets, which implies that no taxes are paid. For future research it is recommended to investigate how a transition from the informal to formal market can aect the lives of the farmers but also the national development of the country. / Namibia har den tredje lägsta befolkningstätheten i världen och en stor del av befolkningen är beroende av småskaligt lantbruk för att överleva. Det som konstaterats under studien är att stora avstånd mellan befolkningen skapar nya utmaningar när det gäller infrastruktur, logistik och kommunikation. Dessa faktorer måste beaktas vid genomförande eller påbörjande av nya verksamheter. Denna forskning undersökte framgångsfaktorer inom befintliga affärsverksamheter, av och för lantbrukare i norra Namibia med fokus på implementering av ny teknik som stödjer och underlättar det dagliga arbetet. Tidigare litteratur påvisade att nuvarande forskning, gällande det bästa sättet att genomföra och starta verksamheter i områden med låg befolkningstäthet för självförsörjande bönder är begränsad. Syftet med denna studie är att skapa en generell förståelse för sammanhanget och identifiera framgångsfaktorer för existerande affärsmodeller. En 8-veckor lång fältstudie utfördes i Namibia under våren 2018. Empirisk data samlades genom kvalitativa intervjuer och workshops med bönder och affärsinitiativtagare som fokuserar på odling och bearbetning av basgrödan mahangu. Resultat visar att ny teknologi är på uppgång och bönder anpassar sig, om än långsamt, till de fördelar som ny teknik innebär. Full acceptans av nya verktyg är emellertid långsam. Detta på grund av långa avstånd, låg inkomst och djupt rotade traditioner. En viktig framgångsfaktor vore att stötta småskaliga jordbruksentreprenörer. Att ha många mindre företag i ett stort område ökar tillgängligheten vilket i sin tur leder till ökad spridning, acceptans och anpassning av ny teknik. De långsiktiga fördelarna med nya företag är att de kan öka livskvaliteten för landsbygden därmed stödja Namibias övergripande utveckling. Det identfierades också att en stor del av befolkningen bedriver verksamhet påde informella marknaderna, vilket innebär att inga skatter betalas. För framtida forskning rekommenderas att undersöka hur en övergång från den informella till den formella marknaden kan påverka böndernas liv, men också landets nationella utveckling.
180

Structural Analysis on Activity-travel Patterns, Travel Demand, Socio-demographics, and Urban Form: Evidence from Cleveland Metropolitan Area

Chen, Yu-Jen 24 August 2017 (has links)
No description available.

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