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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.
111

Aspectos vulcanológicos dos traquidacitos da região de Piraju - Ourinhos (SP) / Volcanological aspects of the Piraju - Ourinhos (SP) trachydacites

Luchetti, Ana Carolina Franciosi 09 April 2010 (has links)
As rochas vulcânicas ácidas da região de Piraju - Ourinhos fazem parte da grande manifestação vulcânica, de natureza predominantemente básica, ocorrida na Bacia do Paraná no Cretáceo, em decorrência da quebra do continente de Gondwana, dando origem à Província Magmática do Paraná. Estas rochas estão agrupadas no Membro Chapecó que, junto com o Membro Palmas, constituem os litotipos ácidos da Formação Serra Geral, perfazendo 3% do volume total do material vulcânico da Província. As rochas vulcânicas ácidas de Piraju - Ourinhos afloram seguindo a direção do Rio Paranapanema, numa área de 65 por 20 km, totalizando 1300 km2 de superfície, e assentam-se sobre os arenitos da Formação Botucatu, sendo recobertas pelos basaltos da Formação Serra Geral. Há controvérsias na literatura sobre os modos de erupção e colocação de certas unidades vulcânicas ácidas extensas e de grande volume, relacionadas a grandes províncias basálticas, se lavas extensas ou ignimbritos reomórficos de alto grau. O objetivo deste trabalho foi caracterizar as rochas vulcânicas ácidas de Piraju - Ourinhos, dando enfoque aos aspectos vulcanológicos, especialmente físicos, através de levantamento de perfis de detalhe, descrições de estruturas observadas e micropetrográficas, além de estimativas de viscosidades, de forma a fornecer subsídios para um melhor entendimento da origem e evolução do vulcanismo ácido da Formação Serra Geral na região em questão. Quimicamente estas rochas foram classificadas como traquidacitos, sendo divididos, segundo características texturais, em cinco tipos: chocolate, cinza vítreo, bandado/laminado, sal e pimenta e granular. Os traquidacitos são porfiríticos com fenocristais, principalmente de plagioclásio e subordinadamente de clinopiroxênios (augita e pigeonita), minerais opacos (titanomagnetita e magnetita) e apatita. A matriz é vítrea a holocristalina conforme a localização no perfil do corpo vulcânico e a sua espessura, e exibe devitrificação acentuada e de alta temperatura verificada pela presença de esferulitos com fibras longas e textura micropoiquilítica, além de feições de resfriamento rápido (quenching) como cristais de plagioclásio ocos ou com terminações em cauda de andorinha. Foram observadas estruturas como juntas de baixo ângulo cerradas paralelas à laminação ou bandamento no traquidacito, juntas do tipo lápis, brechas de interação de lava com sedimentos e vitrófiro de topo de derrame, isto aliado à ausência de fenocristais quebrados, shards, púmices, fragmentos líticos, fiammés, zonas soldadas e à ausência de vestígios de caldeira na região. Estas feições sugerem que os traquidacitos de Piraju - Ourinhos foram colocados na superfície através de fissuras, como fluxos de lava de baixa viscosidade, altas temperaturas e altas taxas de efusão, o que permitiu fluírem para longe do conduto. Na porção inferior do pacote vulcânico, correspondente aos primeiros pulsos, com o predomínio de traquidacito chocolate vesiculado a escoriáceo alternado com o traquidacito cinza vítreo, a correlação entre os derrames individuais é difiícil devido à influência do paleorelevo irregular. Em direção ao topo do pacote os corpos vulcânicos estão estruturados na forma de derrames extensos e tabulares, apresentando zonas basais, centrais e superiores bem definidas. / The acid volcanic rocks of the Piraju - Ourinhos region are part of the predominantly basic volcanic manifestation that occurred in the Paraná Basin in the Cretaceous, due the breakup of the Gondwana continent, giving rise to the Paraná Magmatic Province. These rocks are grouped in the Chapecó Member which, together with the Palmas Member, constitute the acid lithotypes of the Serra Geral Formation, accounting for 3% of the total volume of the Provinces volcanic material. The Piraju - Ourinhos acid volcanic rocks outcrop following the valley of the Paranapanema River, occupying an area of 65 by 20 km with an 1300 km2 surface, and overlie the Botucatu Formation sandstones, being capped by the Serra Geral Formation basalts. There is a controversy in the literature about the eruption styles and emplacement of certain extensive acid volcanic units, related to large basaltic provinces, whether as extensive lavas or high temperature rheomorphic ignimbrites. The aim of this work was to characterize the Piraju Ourinhos acid volcanic rocks, focusing on volcanological aspects, specially the physical ones, through detailed profiles survey, structural and micropetrographic descriptions, as well as viscosity estimates, to provide basis for a better understanding of the origin and evolution of the Serra Geral Formation acid volcanism in the region. These rocks were classified chemically as trachydacites, being divided, according to textural characteristics, in five types: chocolate, gray glassy, banded/laminated, salt and pepper and granular. The trachydacites are porphyritic with mainly plagioclase fenocrystals and subordinately clinopyroxenes (augita and pigeonite), opaque minerals (titanomagnetite and magnetite) and apatite. The groundmass is glassy to holocrystalline depending on the position in the profile and thickness of the volcanic body and display high temperature devitrification features such as spherulites with long fibers and micropoikilitic texture, as well as quench textures such as hollow or swallow tail plagioclase crystals. Structures observed include sheeting joints parallel to flow lamination or banding, pencil joints, lava-sediment interaction breccias and lava flow top vitrophyre. Broken phenocrysts, shards, pumices, lithic fragments, fiammés, welded layers and caldera structures were not observed in the area. These features suggest that the emplacement of the Piraju - Ourinhos trachydacites occurred as low viscosity, high temperature and high effusion rate fissural lava flows, allowing the lava to flow large distances from the vent. In the lower part of the volcanic pile, corresponding to the first pulses, vesicular to scoriaceous chocolate trachydacite alternated with gray glassy trachydacite predominate and the correlation between single lava flows is difficult due to the irregular paleorelief. Towards the top of the pile volcanic bodies are structured as extensive and tabular lava flows, exhibiting well defined basal, central and superior zones.
112

A Novel Tension-Member Follower Train for a Generic Cam-Driven Mechanism

LaPierre, Jeffrey A 13 June 2008 (has links)
"Many assembly machines for consumer products suffer from the fact that the mechanisms used to impart the necessary assembly motions to the product are orders of magnitude more massive than the product payloads that they carry. This characteristic subsequently limits the operating speed of the machine. If the follower train could be made less massive without sacrificing accuracy and control, it would therefore allow higher speeds. It is well-known that structures that carry only tensile loads can be much less massive than those that must also carry compressive loads. This concept is demonstrated in many structures, such as the suspension bridge. This master’s project set out to investigate the feasibility of a tension-member follower train for a generic cam-driven pick and place mechanism. This system was first dynamically simulated using a computer model, and then tested by constructing a proof of concept prototype. A cam-driven, low-mass tension member (in this case a spring steel strip over pulleys) under spring preload was used to replace the bellcranks and connecting rods typical of a conventional follower train. The system was determined to be feasible and will allow for increased operating speeds at potentially lower costs as an additional benefit."
113

Litofaciální vývoj a cyklická stavba svrchní části porubských vrstev (serpuchov) ve východní části OKR / Lithofacies and cyclic pattern of the upper part of the Poruba Member (Serpukhovian) in the eastern part of the Ostrava-Karviná coalfield

Michlová, Nikol January 2019 (has links)
The diploma thesis studies lithofacies and cyclic pattern of about 200 m thick upper part of the Poruba Member (Serpukhovian) in the Karviná area of the Ostrava-Karviná coalfield. The objective of this thesis is to identify laterally persistent cycles from the local ones by the set of cross-sections and to better understand their formation, especially the role of glacio- eustatic sea level changes. Set of cross-sections constructed from boreholes were used for this study. The three genetic cycles were identified in the thesis based on previous studies of Gastaldo et al. (2009). From base to top the cycles are the (i) Max, (ii) Otakar a (iii) Gaebler. Their thickness fluctuates between 19.9 and 109.9 meters. The genetic cycles are bounded, with one exception, by a transgressive erosional surface of important faunal marine bands. From the set of cross-sections and maps of thickness and sand content (%), constructed for individual genetic cycles, it is obvious that the area of maximum thickness corresponds to area of increased content of medium- and coarse-grained sandstone. Maxima of sand content and thicknesses follow NNE-SSW direction, which is in agreement with basin axis. These maxima are interpreted as areas occupied by fluvial channels that are responsible for deposition of coarse- grained...
114

Cyklická stavba nýřanských vrstev (pennsylvan) v centrální části kladensko-rakovnické pánve / Cyclic architecture of the Nýřany Member (Pennsylvanian) in the central part of the Kladno-Rakovník Basin

Páchová, Helena January 2019 (has links)
This master thesis studies cyclic pattern of the Nýřany Member (Middle Pennsylvanian, Moscovian) in the Slaný coalfield situated in the Kladno-Rakovník Basin. The main objective is to identify laterally persistent cycles and to find out their possible origin. Set of cross-sections constructed from boreholes proved lateral stability of 40 - 60 m thick units called the mesocycles. In all, eight mesocycles were identified (N0 - N7), of which the mesocycle N7 was newly defined. Maps of thickness and sand content constructed for each mesocycle provided additional information on subsidence rate and distribution of clastic sediments by fluvial processes. Lateral stability of the mesocycles suggests their allocyclic character and regionally operating mechanism responsible for their formation. Regularity in repetition of the mesocycles as indicated by their similar thicknesses and architecture may suggest that the mechanism could be periodic, possibly of climatic origin. This hypothesis is supported by calculated mean duration of the mesocycles to be ~ 400 ky, based on previously published high-precision CA-ID-TIMS radioisotopic ages of intercalated tonsteins. This "periodicity" approaches 413 ky periodicity of the long eccentricity, one of the Milankovitch orbital cycles, which, in turn, is considered here...
115

Aspectos vulcanológicos dos traquidacitos da região de Piraju - Ourinhos (SP) / Volcanological aspects of the Piraju - Ourinhos (SP) trachydacites

Ana Carolina Franciosi Luchetti 09 April 2010 (has links)
As rochas vulcânicas ácidas da região de Piraju - Ourinhos fazem parte da grande manifestação vulcânica, de natureza predominantemente básica, ocorrida na Bacia do Paraná no Cretáceo, em decorrência da quebra do continente de Gondwana, dando origem à Província Magmática do Paraná. Estas rochas estão agrupadas no Membro Chapecó que, junto com o Membro Palmas, constituem os litotipos ácidos da Formação Serra Geral, perfazendo 3% do volume total do material vulcânico da Província. As rochas vulcânicas ácidas de Piraju - Ourinhos afloram seguindo a direção do Rio Paranapanema, numa área de 65 por 20 km, totalizando 1300 km2 de superfície, e assentam-se sobre os arenitos da Formação Botucatu, sendo recobertas pelos basaltos da Formação Serra Geral. Há controvérsias na literatura sobre os modos de erupção e colocação de certas unidades vulcânicas ácidas extensas e de grande volume, relacionadas a grandes províncias basálticas, se lavas extensas ou ignimbritos reomórficos de alto grau. O objetivo deste trabalho foi caracterizar as rochas vulcânicas ácidas de Piraju - Ourinhos, dando enfoque aos aspectos vulcanológicos, especialmente físicos, através de levantamento de perfis de detalhe, descrições de estruturas observadas e micropetrográficas, além de estimativas de viscosidades, de forma a fornecer subsídios para um melhor entendimento da origem e evolução do vulcanismo ácido da Formação Serra Geral na região em questão. Quimicamente estas rochas foram classificadas como traquidacitos, sendo divididos, segundo características texturais, em cinco tipos: chocolate, cinza vítreo, bandado/laminado, sal e pimenta e granular. Os traquidacitos são porfiríticos com fenocristais, principalmente de plagioclásio e subordinadamente de clinopiroxênios (augita e pigeonita), minerais opacos (titanomagnetita e magnetita) e apatita. A matriz é vítrea a holocristalina conforme a localização no perfil do corpo vulcânico e a sua espessura, e exibe devitrificação acentuada e de alta temperatura verificada pela presença de esferulitos com fibras longas e textura micropoiquilítica, além de feições de resfriamento rápido (quenching) como cristais de plagioclásio ocos ou com terminações em cauda de andorinha. Foram observadas estruturas como juntas de baixo ângulo cerradas paralelas à laminação ou bandamento no traquidacito, juntas do tipo lápis, brechas de interação de lava com sedimentos e vitrófiro de topo de derrame, isto aliado à ausência de fenocristais quebrados, shards, púmices, fragmentos líticos, fiammés, zonas soldadas e à ausência de vestígios de caldeira na região. Estas feições sugerem que os traquidacitos de Piraju - Ourinhos foram colocados na superfície através de fissuras, como fluxos de lava de baixa viscosidade, altas temperaturas e altas taxas de efusão, o que permitiu fluírem para longe do conduto. Na porção inferior do pacote vulcânico, correspondente aos primeiros pulsos, com o predomínio de traquidacito chocolate vesiculado a escoriáceo alternado com o traquidacito cinza vítreo, a correlação entre os derrames individuais é difiícil devido à influência do paleorelevo irregular. Em direção ao topo do pacote os corpos vulcânicos estão estruturados na forma de derrames extensos e tabulares, apresentando zonas basais, centrais e superiores bem definidas. / The acid volcanic rocks of the Piraju - Ourinhos region are part of the predominantly basic volcanic manifestation that occurred in the Paraná Basin in the Cretaceous, due the breakup of the Gondwana continent, giving rise to the Paraná Magmatic Province. These rocks are grouped in the Chapecó Member which, together with the Palmas Member, constitute the acid lithotypes of the Serra Geral Formation, accounting for 3% of the total volume of the Provinces volcanic material. The Piraju - Ourinhos acid volcanic rocks outcrop following the valley of the Paranapanema River, occupying an area of 65 by 20 km with an 1300 km2 surface, and overlie the Botucatu Formation sandstones, being capped by the Serra Geral Formation basalts. There is a controversy in the literature about the eruption styles and emplacement of certain extensive acid volcanic units, related to large basaltic provinces, whether as extensive lavas or high temperature rheomorphic ignimbrites. The aim of this work was to characterize the Piraju Ourinhos acid volcanic rocks, focusing on volcanological aspects, specially the physical ones, through detailed profiles survey, structural and micropetrographic descriptions, as well as viscosity estimates, to provide basis for a better understanding of the origin and evolution of the Serra Geral Formation acid volcanism in the region. These rocks were classified chemically as trachydacites, being divided, according to textural characteristics, in five types: chocolate, gray glassy, banded/laminated, salt and pepper and granular. The trachydacites are porphyritic with mainly plagioclase fenocrystals and subordinately clinopyroxenes (augita and pigeonite), opaque minerals (titanomagnetite and magnetite) and apatite. The groundmass is glassy to holocrystalline depending on the position in the profile and thickness of the volcanic body and display high temperature devitrification features such as spherulites with long fibers and micropoikilitic texture, as well as quench textures such as hollow or swallow tail plagioclase crystals. Structures observed include sheeting joints parallel to flow lamination or banding, pencil joints, lava-sediment interaction breccias and lava flow top vitrophyre. Broken phenocrysts, shards, pumices, lithic fragments, fiammés, welded layers and caldera structures were not observed in the area. These features suggest that the emplacement of the Piraju - Ourinhos trachydacites occurred as low viscosity, high temperature and high effusion rate fissural lava flows, allowing the lava to flow large distances from the vent. In the lower part of the volcanic pile, corresponding to the first pulses, vesicular to scoriaceous chocolate trachydacite alternated with gray glassy trachydacite predominate and the correlation between single lava flows is difficult due to the irregular paleorelief. Towards the top of the pile volcanic bodies are structured as extensive and tabular lava flows, exhibiting well defined basal, central and superior zones.
116

Ledarskap på distans : Förutsättningar, utmaningar och möjligheter

Billquist, Jessica January 2019 (has links)
En kvalitativ studie som syftar till att analysera vad som kan skapa bra förutsättningar för ett ledarskap på distans, beskriva vilka utmaningar och möjligheter detta kan medföra och uppmärksamma upplevda skillnader mellan att leda på distans och att leda på plats. Åtta semistrukturerade intervjuer genomfördes där tidigare forskning om leader-member exchange theory och arbetsrelaterad känsla av sammanhang låg till grund för intervjuguiden. En tematisk analys genomfördes vilken resulterade i fem teman: tydlighet, kommunikation, tillgänglighet, relationer och stöd samt kompetens och effektivitet. De fyra första temana bidrog till att skapa bra förutsättningar för ett ledarskap på distans, utmaningar som framkom var att skapa förutsättningarna. I dessa teman fanns även skillnader mellan typerna av ledarskap. Det femte temat var övergripande och kom att stå för möjligheter med ett ledarskap på distans och anledningar till att det var nödvändigt. Studien visar en komplex bild av ledarskap på distans där alla teman samverkar.
117

ANHÖRIGAS UPPLEVDA SITUATION NÄR EN NÄRSTÅENDE VÅRDAS PÅ EN INTENSIVVÅRDSAVDELNING : -En litteraturöversikt / FAMILY MEMBERS’ EXPERIENCES WHEN A RELATIVE RECEIVES CARE IN AN INTENSIVE CARE DEPARTMENT : -A literature review

Bergström, Henrik, Hammar, Andreas January 2019 (has links)
Bakgrund: Intensivvårdsavdelningen är en avdelning där kritiskt- och akut sjuka patienter vårdas. Avdelningen har specialiserade rutiner och utrustning för omvårdnad samt övervakning. Sjuksköterskan på en intensivvårdsavdelning har ansvar över omvårdnaden av patienten tillsammans med ledandet av omvårdnadsarbetet i vårdlaget. Utöver har även sjuksköterskan ett ansvar att uppmärksamma den anhöriga. Därför är det viktigt för sjuksköterskan att förstå anhörigas upplevelser i denna situation för att kunna ge en god omvårdnad även till dem. Syfte:  Att beskriva anhörigas upplevda situation när en närstående vårdas på en intensivvårdsavdelning. Metod: Litteraturöversikt av vetenskapliga artiklar med kvalitativ ansats med ett anhörigperspektiv för att belysa upplevelser. Resultat: Anhöriga kunde uppleva flera faktorer som påverkade situationen negativt. Rutiner, teknisk utrustning och vårdinsatser upplevdes främmande och förvirrande. Situationen gjorde det svårt för den anhörige att uppleva sig nära patienten. Anhöriga upplevde att god kommunikation och information påverkade situationen positivt. Anhöriga upplevde det viktigt att kunna vara delaktig i vården och beslutsfattandet. Slutsats: Att som anhörigas hamna på en intensivvårdsavdelning är en främmande situation som skiljer sig från andra avdelningar. Det finns olika regler, utrustning och situationer som försvårar möjligheten för den anhörige att förstå och se sammanhanget. Det är av betydelse att vården uppmärksammar och skapar möjlighet för en ökad förståelse och ett sammanhang för de anhöriga. / Background: The intensive care unit is a department where critically and acute sick patients are being treated. The department has specialized routines, equipment to treat and screening. Nurses on a intensive care unit are responsible for the treatment of patients as well as the leadership of the workforce. The nurses are also responsible to acknowledge the patient’s relatives. Therefore, it is of great importance for the nurses to understand relatives’ experiences in this situation, to be able to give treatment of good quality to relatives too. Aim: To describe the experience of relatives to patients who are being treated at the intensive care unit. Method: A literature review of scientific articles with a qualitative standpoint, aimed towards the experiences of relatives to intensive care unit patients. Results: Relatives experienced that a lot of factors affected them negatively. Routines, equipment and treatment were experienced as unfamiliar and confusing. The situation made it hard for the relatives to experience being close to the patient. Relatives experienced that good communication and information made the situation positive. Relatives experienced that being a part and having a say in the patients’ treatment were important. Conclusion: To be a relative at the intensive care unit can feel unfamiliar and differ from other kinds of departments. There are rules, equipment and situations that makes it difficult for the relatives to see the context of the situation. It is of great importance that the healthcare is attentive and give the relatives the possibility to understand the context.
118

Federating EU development cooperation? : Europe's contributions to international development effectiveness

Steingass, Sebastian Dionysius January 2018 (has links)
The European Union (EU) has long strived to act collectively in the face of international challenges such as poverty, hunger and state fragility beyond its borders. While the EU member states and institutions seek coherent responses to these challenges, they also have partly competing agendas. Yet there has been increasing agreement on collective action. To understand this agreement, this thesis asks how policy professionals contribute to the advocacy of policy norms for collective action between the EU institutions and the member states. The research analyses policy processes in EU development cooperation since the early 2000s. In development cooperation the EU's effectiveness has been particularly contested because of the combination of competing ideas about the EU's role and about how to achieve effective and sustainable development. The research finds that, while formal decisions about collective action remain in the hands of member states, transnational networks of policy professionals in the EU institutions, member state bureaucracies and civil society contribute to shaping the terms of debate regarding the EU's role in effective development cooperation. These network interactions, which form around institutional decision-making centres, transcend the organisational boundaries of member state bureaucracies, EU institutions and civil society organisations. These findings fill a gap in our understanding of how EU norms governing collective external action are advocated as existing research has tended to focus on how institutional structure facilitate state coordination. By concentrating on the cases of Germany and the United Kingdom and their engagement with the EU institutions, the research revises existing, dominant views on norm advocacy in EU external action: It links the previously little related concepts of norm advocacy and discursive networks to analyse the agency and scope of policy professionals in the advocacy of EU policy norms; and it provides new empirical insights into the role of these policy professionals for collective action between the EU institutions and the member states in development cooperation.
119

A characterization of soil organic matter in Holocene paleosols from Kansas

Monson, Jessica Laura Bruse 01 May 2013 (has links)
Carbon isotope studies are commonly used to provide a proxy for past vegetation communities and for evaluating environmental change. Original studies suggested carbon isotope ratios of soil organic matter (SOM) faithfully preserved the isotopic composition of standing vegetation with little or no modification in the pedogenic and shallow burial environment. Recent studies of modern soils and laboratory experiments suggest that this may not necessarily be the case and that degradation of SOM in the burial environment may alter the original C-isotope ratio of bulk SOM. A first step in addressing the issue is to begin to understand the transformations of SOM in the burial environment; of particular interest in this study are transformations involving microbial residues. Sedimentary sequences with stacked buried soils afford the opportunity to study the changes that may occur through time and are especially useful if numerical ages and other environmental proxies are present. The objective of this study is to thoroughly investigate the composition and quantity of organic matter that has been preserved in the surface and buried soils at the Claussen site, using Fourier Transform Infrared Spectroscopy (FTIR), which provides an estimate for the abundance of organic matter components preserved in each paleosol's SOM. We can trace the fate of bioavailable OM and determine the magnitude of preferential decay of SOM with time by first comparing the composition of bulk SOM to the composition of physically protected carbon, located in soil microaggregates (Christensen, 1992) of the stacked buried soils. The results of this project suggest differences in the composition of paleosol and surface soil SOM that could impact paleovegetation interpretations derived from δ13C values.
120

Strategies That Small Business Leaders Use to Motivate Millennial Employees

Nilo, James Alvaro 01 January 2018 (has links)
Millennial workers occupy the majority of employment positions worldwide, which is a concern to business leaders in the United States related to having knowledge and ability to train, motivate, and retain millennial employees. Using Gilbert's behavior engineering model as a conceptual framework, this multiple case study explored the strategies that business leaders used to motivate their millennial employees. The study population included 4 leaders of small restaurant businesses in eastern North Carolina. Data were collected from semistructured, face-to-face interviews using 7 open-ended questions and review of company documents, websites, and social media. Data were coded and analyzed following Morse's method of data analysis. Three themes emerged from data analysis: rewards and recognition, high-quality leader-member relationship, and professional development. The findings of this research are significant for small business leaders who want to implement effective motivational strategies to manage millennial employees to keep their organizations productive and profitable. The implications of this study for positive social change include the potential to help millennial workers grow in their careers, become financially stable, and develop into prospective leaders prepared to propel their organizations and societies in the future.

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