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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.
11

Information Technology, Workplace Organization And The Case Of Sisecam

Gursoy, Serkan 01 July 2003 (has links) (PDF)
This study examines the relations among information technology (IT), workplace organization and the demand for skilled labor. Recently, demand for skilled labor has relatively increased. One of the causes of this great increase is skill- biased technical change. Firms that are intensive users of IT tend to adopt a complementary set of organizational practices that include: decentralization of decision authority and a greater reliance on skill and human capital. I have explored the affects of IT on skill and organizational architecture of firm by using a detailed data which was collected from the aioecam Group of Company. I have tested that IT usage is complementary or substitutionary to a new workplace organization which includes broader job responsibilities, more decentralized decision-making and more self-managing teams together with IT and new organization are complements with worker skill measured in variety of ways.
12

History and preservation of stained glass in the Pacific Northwest : the Povey Bros. Glass Co. of Portland, Oregon /

Heald, Leslie S., January 1999 (has links)
Thesis (M.S.)--University of Oregon, 1999. / Includes vita and abstract. "This thesis examines the operations of the Povey Bros. stained glass studio, active in Portland, Oregon from 1888 to 1929, within the context of historic American stained glass ... [and] concludes with a case study of the First Christian Church in Eugene, Oregon, a 1911 church containing many Povey windows"--P. iv. Includes bibliographical references (leaves 189-195). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p1397797.
13

Dřevozpracující průmysl v Jihočeském kraji - různorodost v hodnocení rizik / Wood-processing industry in South Bohemia - variety of health risk assessment

SEDLÁČKOVÁ, Lucie January 2019 (has links)
In my diploma thesis I deal with the issue of the working environment in the woodworking industry and the diversity of the associated risks, such as noise, dust, vibrations, chemicals, physical load and working position. This issue is current due to the rise of custom joinery. Demand also rises for the quality hard wood and its products, so part of my work deals with this issue as well. I find problematic the variability of the work environment related to measurable environmental parameters. The theoretical part will be based on literature and legislation related to this issue. The areas related to wood-processing operations will be detailed. This issue is handled mainly in relation to the hygiene of work and occupational medicine. Therefore the legislation and terminology, on which the practical part is based, devote a considerable part of the theoretical part. Three companies operating in Southern Bohemia were deliberately selected for research. The practical part is based on the measurement protocols of the individual working environment factors. I obtained the results using secondary analysis of data from measurement protocols of individual factors, professional literature, decrees, government regulations and laws. Two objectives and three research questions have been set for research. Objective 1: The work will identify risk factors for the work of woodworkers. Objective 2: The work will evaluate proposals for employers' precautions to protect the health of workers in individual woodworking plants. V1: Are there significant differences in the occurrence of risk factors in woodworking with regard to the way wood and its products are processed? V2: Are there significant differences in the precautions for the health protection in wood production according to the way of processing of wood and its products? V3: How does hardwood dust affect woodworking technology and health protection precautions? The first objective was chosen for the factual description of the working environment of individual companies, as the individual operations differ significantly from the occurring risk factors and their risk. The second objective was chosen with regard to the importance of properly chosen health protection precautions. Failure to comply with the employer's obligations linked to the protection of workers' health may result in serious and permanent damage to health. The importance of appropriately chosen precautions results from the final part of my work.
14

Cristalização de Biomateriais Vitrocerâmicos e Mineralização em Meio Fisiológico Simulado

Queiroz, Carlos Manuel Gomes de Araújo January 2005 (has links)
We propose new theoretical models, which generalize the classical Avrami-Nakamura models. These models are suitable to describe the kinetics of nucleation and growth in transient regime, and/or with overlapping of nucleation and growth. Simulations and predictions were performed for lithium disilicate based on data reported in the literature. One re-examined the limitations of the models currently used to interpret DTA or DSC results, and to extract the relevant kinetic parameters. Glasses and glass-ceramics with molar formulation 0.45SiO2? (0.45-x)MgO?xK2O?0.1(3CaO.P2O5) (0?x?0.090) were prepared, crystallized and studied as potential materials for biomedical applications. Substitution of K+ for Mg2+ were used to prevent devritification on cooling, to adjust the kinetics of crystallization and to modify the in vitro behaviour of resulting biomaterials. The crystallization of the glass frits was studied by DTA, XRD and SEM. Exothermic peaks were detected corresponding to bulk crystallization of whitlockite-type phosphate, Ca9MgK(PO4)7, at approximately 900ºC, and surface crystallization of a predominant forsterite phase (Mg2SiO4) at higher temperatures. XRD also revealed the presence of diopside (CaMgSi2O6 in some samples. The predominant microstructure of the phosphate phase is of the plate-type, seemingly crystallizing by a 2-dimensional growth mechanism. Impedance spectroscopy revealed significant changes in electrical behaviour, associated to crystallization of the phosphate phase. This showed that electrical measurements can be used to study the kinetics of crystallization for cases when DTA or DSC experiments reveal limitations, and to extract estimates of relevant parameters from the dependence of crystallization peak temperature, and its width at half height. In vitro studies of glasses and glass-ceramics in acelular SBF media showed bioactivity and the development of apatite layers The morphology, composition and adhesion of the apatite layer could be changed by substitution of Mg2+ by K+. Apatite layers were deposited on the surface of glass-ceramics of the nominal compositions with x=0 and 0.09, in contact with SBF at 37ºC. The adhesion of the apatite layer was quantified by the scratch test technique, having been related with SBF?s immersion time, with composition and structure of the glass phase, and with the morphology of the crystalline phase of the glass-ceramics. The structure of three glasses (x=0, 0.045 and 0.090) were investigated by MAS-NMR ( 29Si and 31P), showing that the fraction of Q3 structural units increases with the contents of Mg, and that the structure of these glasses includes orthophosphate groups (PO43-) preferentially connected to Ca2+ ions. Mg2+ ions show preference towards the silicate network. Substitution of Mg2+ by K+ allowed one to change the bioactivity. FTIR data revealed octacalcium phosphate precipitation (Ca8H2(PO4)6.5H2O) in the glass without K, while the morphology of the layer acquires the shape of partially superimposed hemispheres, spread over the surface. The glasses with K present a layer of acicular hidroxyapatite, whose crystallinity and needles thickness tend to increase along with K content. / São propostos novos modelos teóricos, que generalizam o modelo clássico de Avrami-Nakamura, apropriados para a cinética de nucleação e de crescimento em regime transiente, e/ou com sobreposição entre o estágio de nucleação e o de crescimento. Foram efectuadas simulações com base em resultados da literatura, reportados para o dissilicato de lítio. Foram examinadas as limitações dos métodos correntemente usados para obter estimativas de parâmetros cinéticos, com base em resultados de ATD. Desenvolveram-se e investigaram-se vidros e materiais vitrocerâmicos susceptíveis de aplicação biomédica com a formulação molar 0.45SiO2?(0.45-x)MgO?xK2O?0.1(3CaO.P2O5) (0?x?0.090), preparados mediante a substituição de Mg2+ por K+. A cristalização das fritas de vidro foi estudada por ATD, DRX e SEM. Foram detectados picos exotérmicos correspondentes à cristalização de fosfato (cristalização em volume) do tipo whitlockite Ca9MgK(PO4)7 a aproximadamente 900ºC, e de forsterite (Mg2SiO4) acompanhada de alguma diopside (CaMgSi2O6; cristalização superficial) a temperaturas superiores. A microestrutura predominante da fase fosfato é do tipo placa, aparentando cristalizar por um mecanismo de crescimento bidimensional. Foi usada espectroscopia de impedâncias para monitorizar a cristalização em condições em que os ensaios de ATD ou de DSC revelam limitações, recorrendo a alterações significativas de propriedades eléctricas associadas à cristalização da fase de fosfato. Os vidros e vidros cerâmicos desenvolvidos revelaram bioactividade em meio acelular in vitro, desenvolvendo camadas apatíticas em SBF. A morfologia, composição e aderência da camada de apatite pôde ser modulada com base na substituição parcial de Mg2+ por K+. Foram depositadas camadas de apatite sobre vidros ceramizados (x=0 e 0.09), em SBF a 37ºC. A adesão da camada de apatite foi quantificada pela técnica de indentação deslizante tendo sido relacionada com o tempo de imersão em SBF, com a composição e estrutura da fase vítrea, e com a morfologia da fase cristalina dos vidros cerâmicos. Foi investigada a estrutura de três vidros (x=0, 0.045 e 0.090) por MAS-RMN (29Si e 31P), verificando-se que nos vidros mais ricos em Mg, a participação da unidade estrutural Q3 é mais significativa, e que a estrutura dos vidros inclui grupos ortofosfato (PO43-) mais próximos de iões Ca2+ do que dos iões Mg2+, sendo estes incorporados preferencialmente na rede de silicato. A substituição parcial de Mg2+ por K+ permitiu ajustar a cristalização dos materiais vitrocerâmicos e modular a bioactividade pretendida. Resultados de FTIR revelaram precipitação de fosfato octacálcico (Ca8H2(PO4)6.5H2O) no vidro sem K, enquanto que a morfologia da camada adquire a forma de hemisférios parcialmente sobrepostos, espalhados sobre a superfície. Os vidros com K apresentam uma camada de hidroxiapatite acicular, cuja cristalinidade e espessura de agulhas tende a aumentar com o teor de K.
15

Utilização de resíduos de catalisador (ECAT) e cinzas da casca de arroz (CCA) na elaboração de vidros silicatos soda-cal destinados a embalagem / Use of rice rusk ash and spent catalyst as a source of raw material for the production and characterization of soda-lime silicate glasses destined for packaging

ARAUJO, MARIANA S. de 22 June 2016 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T12:39:08Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T12:39:08Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
16

Utilização de resíduos de catalisador (ECAT) e cinzas da casca de arroz (CCA) na elaboração de vidros silicatos soda-cal destinados a embalagem / Use of rice rusk ash and spent catalyst as a source of raw material for the production and characterization of soda-lime silicate glasses destined for packaging

ARAUJO, MARIANA S. de 22 June 2016 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T12:39:08Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T12:39:08Z (GMT). No. of bitstreams: 0 / Estudo realizado acerca da utilização de dois resíduos sólidos industriais (RSI) gerados em grande quantidade no Brasil, na obtenção de vidros soda-cal destinados à produção de embalagens. Os resíduos avaliados foram a cinza de casca de arroz (CCA) e resíduo do catalisador usado das unidades de Craqueamento Catalítico Fluido das Petroquímicas (ECAT), ambos podem ser classificados como resíduos sólidos de classe II de acordo com a norma NBR 10.004. Esta nova proposta para destinação desses resíduos é uma alternativa às atuais disposições, buscando não apenas minimizar os impactos ambientais gerados, mas também a valorização dos mesmos como matérias-primas. Para a produção das amostras, além da utilização dos RSIs, foram também utilizados óxidos fundente (Na2CO3) e estabilizante (CaO). Os resultados obtidos demonstraram que ambos podem ser usados como recebidos (sem tratamento prévio) substituindo matérias-primas importantes, fontes de Al2O3 e SiO2, necessárias para a formação de vidros. As amostras obtidas apresentaram a cor âmbar devido a presença de níquel (íons Ni2+) proveniente do ECAT e transmitância óptica de 18%. Estas, ainda demonstraram boa homogeneidade, i.e., ausência de bolhas e estriais e, resistências hidrolíticas média de 1,33x10-8 g/cm²·dia (superior à um vidro comercial de composição semelhante) de acordo com a ISO695-1984. O vidro obtido é adequado para aplicações que exigem baixa transmitância como embalagens de vidros em geral, os quais não requerem perfeita visibilidade e transparência. O teor de incorporação na composição final das amostras foi de aproximadamente 78% em massa. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
17

Saint-Gobain et Pont-à-Mousson face à la construction européenne 1946-1970 / Saint-Gobain and Pont-à-Mousson facing European Construction from 1946 to 1970

Wang, Wei 27 June 2016 (has links)
Fondée en 1685, la Compagnie de Saint-Gobain est aujourd’hui une très grande firme mondiale. Elle doit à son développement propre, mais aussi à sa fusion avec Pont-à-Mousson. Elle était déjà la première multinationale française au début du XXème siècle. Elle a cherché très tôt l’internationalisation, surtout en direction de l’Europe, s’implantant en Allemagne comme en Italie. Après la deuxième Guerre mondiale, Pont-à-Mousson a pris part à la création de la Communauté économique du charbon et de l’acier (CECA). Cette dernière est considérée comme la première institution conduisant à l’unité européenne, notamment à une Europe économique. Pour les deux entreprises définies chacune comme un centre autonome de décision, il s’agit, dans ce livre, d’étudier le processus de la prise de décision économique, à l’intérieur, d’analyser l’environnement extérieur pendant la période de 1945-1970 dans le contexte de la construction européenne. Pour quelle raison Pont-à-Mousson a-t-il participé avec un tel intérêt à la création de la CECA ? Quel rôle les groupes Saint-Gobain et Pont-à-Mousson ont-ils joué dans l’ouverture du marché commun ? Quels ont été la politique et les objectifs des dirigeants politiques ? L’un des intérêts de l’ouvrage consiste à tenter de définir l’évolution des stratégies passées d’une attitude défensive à une attitude offensive, les deux entreprises à s’adapter à l’Europe et acceptant ainsi la transformation progressive de leur modèle de gestion. C’est très largement la contrainte européenne qu’a poussé à leur rapprochement, sans que celui-ci puisse s’expliquer par la seule pression d’un état français interventionniste : les stratégies d’entreprises elle-même ont joué un rôle déterminant. / Founded in 1685, Company of Saint-Gobain is now a very large global firm, which is due to its own development, but also to its merger with Pont-à-Mousson. In the early twentieth century, the Companies were already the leading French multinational. It sought early internationalization, especially to Europe, establishing itself in Germany and Italy. After World War II, Pont-à-Mousson took part in the creation of the European Coal and Steel Community (ECSC). The latter is considered as the first institution leading to European unity, especially in an economic Europe. For both companies, each defined as an autonomous centre of decision, it is this book that aims to study the inside process of economic decision-making and to analyse the external environment during the 1945-1970 in the context of European integration. Why Pont-à-Mousson has involved with such an interest in the creation of the ECSC? Which role did the groups of Saint-Gobain and Pont-à-Mousson play in the opening of the common market? What were the policy and objectives of the political leaders? One of the interests of this book is to try to define the evolution of strategies, from a defensive attitude to an offensive attitude, the two companies adapt to Europe and thus accepting the gradual transformation in their Management model. This is mostly the European constraint that has pushed them closer, rather than under the only pressure pushed by an interventionist French state: strategies of the Company itself played a decisive role.
18

The American Studio Glass Movement: A Regional Study of its Birth in Northwest Ohio

Harrington, Kaysie Marie 26 November 2018 (has links)
No description available.
19

Finns det ett samband mellan bullernivå och spänning i m. trapezius? : En studie på operatörer inom glastillverkningsindustrin

Fransson, Linda, Bergenfeldt, Karin January 2018 (has links)
Sammanfattning Titel: Finns det ett samband mellan bullernivå och spänning i m. trapezius? Bakgrund: Företaget Saint-Gobain Sekurit Scandinavia AB tillverkar bilglas. I deras arbetsmiljöarbete ingår konceptet Smart Workplace. En del av det arbetet behandlar belastningsergonomi och bullerexponering. Syfte: Syftet med examensarbetet var att se om det fanns en korrelation mellan minskat buller och minskad muskelspänning. Målet var att kunna påvisa om operatörer i det aktuella fallet ute i produktion fick minskad muskelaktivitet i m. trapezius eller inte, när bullernivån minskar. Dessutom undersöktes vilka åtgärdsmöjligheter som fanns, kopplat till Smart Workplace, för att minska bullerexponeringen. Teori: Sambandet mellan bullerexponering och spända muskler är relativt outforskat och få forskningsstudier har gjorts. Det finns dock visade samband mellan bullerexponering och hormoner, blodtryck samt hjärtfrekvens. Metod: Tretton operatörer som arbetade vid linje 5230 mättes med EMG-mätare på en nackmuskel på höger sida medan de drog höger hand längs övre kanten på ett bilglas. Arbetsplatsen valdes ut i samråd med företaget. Arbetsmomentet var likadant som operatörer normalt utförde på arbetsplatsen. Mätning utfördes i sex minuter, halva tiden utan hörselkåpor och halva tiden med hörselkåpor. I samband med EMG-mätningarna utfördes även ljudnivåmätning för att säkerställa att ljudnivån var densamma vid alla mätningar. Resultat: Resultatet visade att det inte gick att påvisa att minskad ljudtrycksnivå ger minskad muskeltonus. Däremot visade resultatet på de lägsta 10 % av RVE-värdena att det blev en skillnad om operatörerna hade hörselkåpor eller inte vilket betyder att det inte går att utesluta att det kan finnas ett samband mellan minskat buller och minskad muskeltonus. Den dagliga bullerexponeringsnivån på linje 5230 var 84,7 (± 4,2) dB(A). Kåporna dämpade mer än nödvändigt jämfört med den bullerexponering som operatörerna utsattes för. Diskussion: Felkällor som noterades var författarnas inverkan på operatören vid mätningen, svårigheter med EMG-utrustning, felaktig kalibrering, placering av EMG-elektroderna, underhudsfett och hudmotstånd samt avläsning av diagram. Vidare studier bör utforska området ytterligare då inte så många studier finns inom området. Intressant fokus hade varit mätning av muskelspänning under längre tid samt med högre bullerexponering. Slutsats: Denna studie kan inte påvisa att minskad ljudtrycksnivå ger minskad muskeltonus. Området kring linje 5230 hade en daglig bullerexponeringsnivå på 84,7 (± 4,2) dB(A) vilket innebär att åtgärder måste sättas in för att minska bullernivån både för att klara lagkraven men också för att nå målen med Smart Workplace. För framtida arbetsplatser på SG Sekurit Scandinavia är det avgörande att kraven på maximala bullernivåer finns med som ett kriterium vid upphandling. Om man inte klarar nivåerna för bullerexponeringen är det viktigt att beräkning enligt HML-metoden genomförs för att kunna välja rätt hörselskydd som ger korrekt dämpning. / Abstract Title: Is there a correlation between noise level and tension in m. trapezius? Background: The company Saint-Gobain Sekurit Scandinavia AB manufactures car glass. Their work environment improvement includes a concept called Smart Workplace. A part of that work contains ergonomics and noise exposure. Aim: The aim of this master thesis was to see if there was a correlation between reduced noise level and reduced muscle tension. The goal was to demonstrate if the operators in the studied environment in production got reduced muscle tension in m. trapezius or not, when the noise level was reduced. It was also investigated which possibilities for actions there was, according to Smart Workplace, to reduce noise exposure. Theory: The correlation between noise exposure and muscle tension is relatively unexplored. Few research studies have been done on this topic. However research has shown correlation between noise exposure and hormones, blood pressure and heart rate. Method: Thirteen operators who worked on the line 5230 were measured with EMG-equipment on a neck muscle on their right side while they moved the right hand over the upper side of a car glass. The workstation was chosen in consultation with the company and the work situation was the same as the one the operators performed in their normal work. The EMG-measurements took place during six minutes, half the time without earmuffs and half the time with earmuffs. In connection with the EMG-measurements the noise level was measured to ensure that the noise level was the same. Results: The results showed that there is no correlation between reduced noise level and decreased muscle tonus. However the result from the lowest 10 percent of the RVE-measurements showed a difference if the operators had earmuffs or not, which means that a correlation between reduced noise and reduced muscle tonus can`t be excluded. The daily noise exposure level at line 5230 was 84,7 (± 4,2) dB(A). The attenuation of the earmuffs was too high compared to the noise level the operators were exposed to. Discussion: Error sources was the writers influence on the operators during the measurements, difficulties with the equipment during the EMG-measurement, wrong calibration, the location for the EMG-electrodes, fat under the skin and resistance on the skin and reading of the diagram. Further studies should be done to investigate this topic more since there are few studies in this field. An interesting focus would be to measure during a longer period of time or with higher noise levels. Conclusion: This study cannot show that reduced noise level gives reduced muscle tension. The area around line 5230 had a daily noise exposure level of 84,7 (± 4,2) dB(A) which means that action must be taken to reduce the noise level both in order to fulfill legal requirements and also to reach the goals for Smart Workplace. For future workplaces at SG Sekurit Scandinavia it is crucial that the requirement for maximum noise level is a criteria from the start. If the company cannot meet the requirements on noise levels it is important that calculations are done according to the HML-method to be able to choose the right hearing protectors.
20

Hospodářská krize 1929-1934 a její dopad na jablonecké sklářství se zvláštním zřetelem na oblast Železnobrodska / Economic crisis in 1929-1934 and its impact on the Jablonec glass industry with special reference to Železný Brod region

Bursová, Veronika January 2012 (has links)
A B S T R A C T This thesis analyzes the impact of the economic crisis in 1929-1934 on the Jablonec glass making with main attention to the district Železný Brod. One of the main causes of decline of the Czechoslovak glass industry in the first half of the 30s of 20th century was formed by pro-export focus. The region of Železný Brod and Jablonec nad Nisou had represented sites with major export, production and refining of glass that were for this reason by the economic crisis strongly affected. Deteriorating economic conditions at the beginning of 30s have resulted in intensified state intervention in industry, including the glass manufacturing as one of the most affected industrial areas. Because mostly cartels had regulatory function in the industry, a number of agreements among the glass producers in Jablonec nad Nisou and Železný Brod area were concluded. This thesis considers with different types of production and refining of the glass in order to offer the complete overview over the glass production in districts Jalonec nad Nisou and Železný Brod. The second part puts also emphasis on the social status of domestic craftsmen considering their relations with employers, which determined in times of economic crisis the legislation enacted after establishment of the Czechoslovak Republic, in the 20s and...

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