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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.
31

Avaliação de propriedades mecânicas e microestruturais de juntas de aços maraging soldadas por meio dos processos laser e feixe de elétrons / Evaluation of mechanical and microstructural properties of joints in maraging steel welded by laser and electron beam welding

Maximo, Henry Wilson Pohling 07 May 2014 (has links)
Neste trabalho estudou-se as propriedades obtidas em juntas soldadas pelo processo de soldagem a laser do tipo estado sólido de onda contínua guiado por fibra, e os resultados foram comparados com juntas soldadas pelo processo feixe de elétrons. O material utilizado foi o aço maraging 350 - ASTM A 538 Grade C. As soldas realizadas com o processo feixe de elétrons possuem um procedimento de soldagem aprovado. A junta selecionada para a elaboração do trabalho foi do tipo sobreposta com material de base de espessuras diferentes, respectivamente iguais a 1,00 e 0,78 mm. As juntas soldadas foram avaliadas por: ensaio de cisalhamento, dureza Vickers e caracterização microestrutural das diversas regiões das juntas soldadas. Foram realizadas análises por microscopia óptica e microscopia eletrônica de varredura usando espectrometria de energia dispersiva (MEV/EDS). Foi realizado o teste de hipótese como técnica para a análise dos dados provenientes dos ensaios experimentais. Nas juntas soldadas com ambos processos não foi verificada a presença de descontinuidades, poros e depressões na superfície do cordão. Os resultados indicam que as condições usadas em ambos os processos de soldagem foram satisfatórias e possibilitaram a soldagem do aço maraging 350 atendendo aos requisitos necessários. / In this work, the welds made by a continuous wave diode pumped solid state laser guided by fiber were studied and the results were compared with welded joints of electron beam welding. The material used was maraging 350 steel ASTM A 538 Grade C. The welding process performed with electron beam welding has a approved welding procedure. The joint chosen for the preparation of the work was the lap joint type with different thicknesses base material respectively equal to 1,00 and 0,78 mm. The welded joints were evaluated by mechanical tests like shear test, Vickers hardness and microstructural characterization of the various regions of the welded joints. Analyzes were performed by optical microscopy and scanning electron microscopy using energy dispersive spectrometry (SEM/EDS). The hypothesis test technique was done for the analysis of data from experimental tests. For both welding process was not detected in the welded joints the presence of discontinuities, pores and depressions on the weld fillet surface. The results indicate that the conditions used for both welding process were satisfactory and allowed the welding of maraging 350 steel meeting necessary requirements.
32

Estudo comparativo da conformabilidade mecÃnica dos aÃos MAR 350 e MAR 300 / Comparative study of mechanical forming of MAR350 and Mar300 steels.

Nathanael Wagner Sales Morais 18 December 2013 (has links)
nÃo hà / Os aÃos maraging sÃo materiais de ultra-alta resistÃncia que tem grande importÃncia tecnolÃgica devida sua aplicaÃÃo nos setores nuclear e bÃlico. Devido suas aplicaÃÃes de responsabilidade, à necessÃrio compreender como se comportam as propriedades plÃsticas desses materiais, pois a literatura carece de informaÃÃes sobre o comportamento mecÃnico dos aÃos Mar350 e de liga desenvolvida Mar350*. Esse trabalho investigou como a diferentes nÃveis de deformaÃÃo à frio influenciam as propriedades de anisotropia plÃstica de ambos materiais. Foram realizadas deformaÃÃes a frio nos nÃveis de 50, 70 e 80% por laminaÃÃo e apÃs foram realizados recozimentos a 900ÂC por 1h variando-se a taxa de resfriamento, resfriado-se as amostras em Ãgua, ao ar e ao forno atà a temperatura ambiente. Os resultados das anÃlises metalogrÃficas mostraram que os materiais nÃo sofrem alteraÃÃes morfolÃgicas nos grÃos com a variaÃÃo de taxa de resfriamento, mas sofrem um coalescimento nas deformaÃÃes de 50 e 70%. As amostras do aÃo Mar350 laminadas a frio em 80% mostraram um ultra-refino de grÃo e a precipitaÃÃo de uma fase intermetÃlica enquanto as amostras do aÃo Mar350* mostraram um refino grÃo quando comparado Ãs demais condiÃÃes para o mesmo aÃo, mas sem sofre um endurecimento significativo. As mediÃÃes de textura mostraram com o evoluir da deformaÃÃo à frio hà uma tendÃncia de âlimpezaâ da textura apresentado mais intensa a fibra γ. As mediÃÃes de microtextura mostram que algumas para a maioria das condiÃÃes estudadas a presenÃa da componente cubo girado menos intensa γ, componentes estas que poderiam ser a justificativa para o afastamento de ΔR de zero e os menores valores de Rm. / The maraging steels are ultra - high strength materials that has great technological importance due its application in military and nuclear sectors . Because its applications, it is necessary to understand how the plastic properties of these materials behave, because the literature lacks information on the mechanical behavior of steel the Mar350 and alloy redeveloped Mar300 . This study investigated how different levels of cold deformation influence the properties of plastic anisotropy of both materials . Cold deformation were carried out on levels of 50, 70 and 80% by rolling and after was made annealing were the materials carried out at 900  C for 1h varying the rate of cooling, the samples were cooled in water , air and the furnace until the room temperature. The results of metallographic analysis showed that the materials do not undergo morphological changes in the grains by varying the cooling rate, but some coarsening undergo a deformation in 50 and 70%. The samples of cold rolled steel Mar350 80% showed an ultra- grain refinement and precipitation of an intermetallic phase while the samples of steel Mar350* showed grain refining compared to the other conditions for the same steel, but without undergoes a significant hardening. The texture measurements showed the evolution of the cold deformation there is a tendency to cleanup texture appears more intense γ fiber . The measurements show that some microtexture for most conditions studied the presence of other components less intense outside the fiber γ , these components that could be the reason for the displacement of ΔR zero.
33

Avaliação de propriedades mecânicas e microestruturais de juntas de aços maraging soldadas por meio dos processos laser e feixe de elétrons / Evaluation of mechanical and microstructural properties of joints in maraging steel welded by laser and electron beam welding

Henry Wilson Pohling Maximo 07 May 2014 (has links)
Neste trabalho estudou-se as propriedades obtidas em juntas soldadas pelo processo de soldagem a laser do tipo estado sólido de onda contínua guiado por fibra, e os resultados foram comparados com juntas soldadas pelo processo feixe de elétrons. O material utilizado foi o aço maraging 350 - ASTM A 538 Grade C. As soldas realizadas com o processo feixe de elétrons possuem um procedimento de soldagem aprovado. A junta selecionada para a elaboração do trabalho foi do tipo sobreposta com material de base de espessuras diferentes, respectivamente iguais a 1,00 e 0,78 mm. As juntas soldadas foram avaliadas por: ensaio de cisalhamento, dureza Vickers e caracterização microestrutural das diversas regiões das juntas soldadas. Foram realizadas análises por microscopia óptica e microscopia eletrônica de varredura usando espectrometria de energia dispersiva (MEV/EDS). Foi realizado o teste de hipótese como técnica para a análise dos dados provenientes dos ensaios experimentais. Nas juntas soldadas com ambos processos não foi verificada a presença de descontinuidades, poros e depressões na superfície do cordão. Os resultados indicam que as condições usadas em ambos os processos de soldagem foram satisfatórias e possibilitaram a soldagem do aço maraging 350 atendendo aos requisitos necessários. / In this work, the welds made by a continuous wave diode pumped solid state laser guided by fiber were studied and the results were compared with welded joints of electron beam welding. The material used was maraging 350 steel ASTM A 538 Grade C. The welding process performed with electron beam welding has a approved welding procedure. The joint chosen for the preparation of the work was the lap joint type with different thicknesses base material respectively equal to 1,00 and 0,78 mm. The welded joints were evaluated by mechanical tests like shear test, Vickers hardness and microstructural characterization of the various regions of the welded joints. Analyzes were performed by optical microscopy and scanning electron microscopy using energy dispersive spectrometry (SEM/EDS). The hypothesis test technique was done for the analysis of data from experimental tests. For both welding process was not detected in the welded joints the presence of discontinuities, pores and depressions on the weld fillet surface. The results indicate that the conditions used for both welding process were satisfactory and allowed the welding of maraging 350 steel meeting necessary requirements.
34

1.000 neue Polizisten in Sachsen? - Aber nicht erst in 10 Jahren!

21 May 2019 (has links)
Ab dem Jahr 2017 sollen jährlich 600 neue Polizistinnen und Polizisten ausgebildet werden. Die 1.000 zusätzlichen Stellen würden bei einem solchen Einstellungskorridor erst im Jahr 2026 erreicht, da den Einstellungen große Altersabgänge gegenüberstehen. Das ergab eine Kleine Anfrage von Valentin Lippmann, innenpolitischer Sprecher der Fraktion BÜNDNIS 90/DIE GRÜNEN. In den nächsten beiden Jahren wird kein einziger Polizist mehr auf der Straße stehen. Die GRÜNEN im Sächsischen Landtag haben den Stellenabbau und die Schließung von Polizeirevieren immer kritisiert und die Neueinstellung von Polizeikräften gefordert. Sachsens Bürgerinnen und Bürger müssen sich sicher sein, dass die Polizei schnell vor Ort ist, wenn sie gerufen wird.
35

Die Einführung von Vorgangsbearbeitungssystemen in der öffentlichen Verwaltung als IT-organisatorischer Gestaltungsprozeß

Knaack, Ildiko 08 December 1999 (has links)
Die Arbeit entwickelt einen konzeptionellen Rahmen für den IT-organisatorischen Gestaltungsprozeß bei der Einführung von Vorgangsbearbeitungssystemen und berücksichtigt dabei die Besonderheiten der öffentlichen planenden Verwaltung (Ministerialverwaltung). Die Einführung von Vorgangsbearbeitungssystemen greift wie kein anderes IT-System zuvor in die Ablauf- und Aufbauorganisation der öffentlichen Verwaltung ein. Vorgangsbearbeitungssysteme eröffnen grundlegend neue Gestaltungsmöglichkeiten der Bearbeitung von Vorgängen und erfordern zugleich eine an die IT-Unterstützung angepaßte, optimierte Organisation der Vorgangsbearbeitung. Der Einführungsprozeß ist durch eine Vielzahl von informationstechnischen und organisatorischen Abhängigkeiten und Wechselwirkungen gekennzeichnet. Informa-tionstechnik und Organisation werden als zwei Determinanten der Gestaltung betrachtet, die bei der Durchführung informationstechnisch-organisatorischer Gestaltungsmaßnahmen zu berücksichtigen sind. Der Gestaltungsbedarf ergibt sich aus der Art und Weise der Nutzung des Vorgangsbearbeitungssystems. Ziel der Gestaltung ist eine schrittweise optimierte und an die Spezifika der Behörde angepaßte Nutzung des Vorgangsbearbeitungssystems. Ausgehend von einer Systematisierung der konventionellen und IT-gestützten Vorgangsbearbeitung und einer Untersuchung, inwieweit Methoden und Konzepte des Softwareengineerings, der Verwaltungsmodernisierung und der Organisationswissenschaft informationstechnisch-organisatorische Wechselwirkungen berücksichtigen, wird das Drei-Ebenen-Modell der IT-organisatorischen Gestaltung als konzeptioneller Rahmen entwickelt. Da die konkrete Durchführung IT-organisatorischer Gestaltungsmaßnahmen von den Spezifika der jeweiligen Behörde und dem einzuführenden Vorgangsbearbeitungssystem abhängig ist, wird der IT-organisatorische Gestaltungsprozeß anhand unterschiedlicher Nutzungsstufen von Vorgangsbearbeitungssystemen und an Beispielen IT-organisatorischer Gestaltung des Projekts DOMEA® verdeutlicht. / The work provides concept standards for the IT-related process of implementation a document- and workflowmanagement-system and at the same time takes into account the distinctive features of the public sector. Like no IT-system before, the implementation of a document- and workflowmanagement-system influences the process and structure of the public sector. Document- and workflowmanagement-systems ensure completely new ways of working and at the same time require an optimal organization of document- and workflowmanagement that fits with the needs of IT-support. The process of implementation is characterized by a large number of IT-related and organizational dependences and interaction. IT and organization are considered as two determinants are crucial of a successful organizational and IT-related framing. The need of framing depends on the way document- and workflowmanagement-system is used. The aim is to gradually optimize the use of document- and workflowmanagement-system and to adapt it to the specific needs of the individual organization. Starting from a systematization of conventional and IT-based document- and workflowmanagement and a study on the dependences of IT and organization with methods and concepts of software-engineering, the modernization of the public sector and with theory of organization, the three-tier-model of IT-based shaping is developed. The concrete organizational an IT-related implementation depends on the specific needs of the individual organization and of the document- and workflowmanagement-system to be implemented. Therefore, the organizational an IT-related implementation will be characterized by different levels of using a document- and workflowmanagement-system and by examples of the DOMEA®-project.
36

A Questionnaire Study to Assess the Value of the Vulnerable Elders Survey, G8, and Predictors of Toxicity as Screening Tools for Frailty and Toxicity in Geriatric Cancer Patients

Hentschel, Leopold, Rentsch, Anke, Lenz, Felicitas, Hornemann, Beate, Schmitt, Jochen, Baumann, Michael, Ehninger, Gerhard, Schuler, Markus 22 May 2020 (has links)
Background: The aim of this study was to identify an appropriate screening instrument for the identification of frail elderly patients in a tertiary cancer center. In order to improve cancer care for older patients, the use of a geriatric assessment (GA) has been proposed to identify frail patients or those who are at a higher risk for chemotherapy-related toxicities. In busy clinical routine, an appropriate screening instrument could be used to spare time- and resource-consuming application of GA. Patients and Methods: We administered the Vulnerable Elders Survey (VES-13), G8 questionnaire, and Predictors of Toxicity (POT) as well as a GA at the first visit of 84 consecutive patients at a single Comprehensive Cancer Center. Analysis for patients’ characteristics as well as sensitivity, specificity, and positive and negative predictive value (npv) was conducted. Results: The median age of the patients was 73 years (range 63–93 years), 61.9% were male, most (63%) suffered from gastrointestinal tumors, 39.3% had a multiple cancer diagnosis, and 53.6% had metastasis. 30 (35.7%) individuals were classified as ‘frail’ by the GA. Sensitivity of G8 was 38.3%, and the npv was 63.8%. Sensitivity for VES-13 was 57.1%, and npv was 76.3%. Sensitivity of POT was 72.7%, and the npv was 80.6%. Conclusion: For the first time, the VES13, G8, and POT are compared in a sample of older German patients. The POT seems to be a sufficient screening tool to identify frail patients in a tertiary referral cancer center and helps to save time and resources compared with a complete GA.
37

Plauen 1945 bis 1949 - vom Dritten Reich zum Sozialismus. Entnazifizierung und personell-struktureller Umbau in kommunaler Verwaltung, Wirtschaft und Bildungswesen

Krone, Andreas 31 January 2001 (has links)
Die Arbeit untersucht den gesellschaftlichen Umbruch in der Spitzenstadt Plauen vom Ende des Zweiten Weltkrieges bis zur Gründung der DDR. Detailliert und mit zahlreichen Beispielen unterlegt wird die Entnazifizierung in ihren verschiedenen Phasen bis zum offiziellen Abschluss im März 1948 dargestellt. Parallel zur politischen Säuberung vollzieht die Studie die personellen und strukturellen Reformen in der Stadtverwaltung ebenso wie im Schulwesen nach. Wesentliche Besonderheit dabei für Plauen: Hier war die SED von 1946 bis 1950 in der Stadtverorndetenversammlung in der Minderheit, zudem stellte die LDP den Oberbürgermeister, was den Transformationsprozess von einer Diktatur in eine andere zumindest erschwerte. Für die Wirtschaft waren in den Nachkriegsjahren im stark zerstörten Plauen Trümmerberäumung und Wiederaufbauarbeiten prägend. Der Neubeginn in Industrie und Handwerk wurde maßgeblich behindert durch Demontagen und schier unerfüllbare Arbeitskräfte-Anforderungen der Sowjets für die Wismut. Der Schulbetrieb begann im Herbst 1945 unter katastrophalen materiellen und räumlichen Bedingungen. Ab dem Schuljahr 1946/47 griff das Konzept der Einheitsschule. Die Entnazifizierung schlug hier besonders hart durch, so dass die Neulehrerausbildung seit Anfang 1946 immer mehr an Bedeutung gewann. Dabei wurde besonderer Wert auf den "politischen" Lehrer gelegt.
38

Erfolgreiche Bürger-Behörden-Kontakte

Goldschmidt, Rüdiger 14 January 2003 (has links)
In dieser Diplomarbeit wird eine Beziehungsstruktur von Konstrukten erarbeitet und empirisch geprüft, die den grundsätzlichen und insbesondere den differenzierten Einfluss von Vertrauen auf die Zufriedenheit mit einem spezifischen Kontakt zwischen Bürger und Behörde abbildet.
39

Generative Incubators

Roth, Steffen, Vordank, Tino 13 February 2007 (has links)
Starting the own business is sometimes a dream sometimes a nightmare but undoubtedly from a macro-economic perspective it is considered to be a promising concept to secure long-term economic growth and society’s welfare, at least in Germany. Strong efforts were made to support start ups and potential entrepreneurs to run their own business. A plethora of programs were launched which were supposed to facilitate the start up process – but reality is disenchanting: The published data in the 2004 GEM indicate that the idea of an entrepreneurial society in Germany is still far beyond its realization. Germany ranks 17th out of 31 GEM states in terms of “nascent entrepreneurs” and only 22nd regarding the “young entrepreneurs”. Compared to other GEM countries the German adults are considered to be more pessimistic in terms of entrepreneurial issues: The chances of establishing a successful business are evaluated lower than the years before. On the other hand the context factors which are considered to influence the start up opportunities especially in terms of governmental support and physical infrastructure were evaluated to be one of the best. Especially concerning the latter aspect strong efforts have been made to support entrepreneurs. In this context, and maybe because of - A “… post-1970s fascination with ‘high-tech’ regions worldwide” (Cooke/Leydesdorff 2006: 9), - A continuous liberalization of the world market and its impact on national production systems (which is well discussed in the context of the conversion of cooperatives), or - The dawn of the concept of national innovations systems (e.g. Lundvall 1988; Cozzens et al. 1990), For more than two decades, one promising concept of sustaining entrepreneurs was seen in the idea of incubators1 which mainly offer support in terms of infrastructure and funding opportunities. Meantime, we observe that questions emerge of how effective and efficient incubators work as one major instrument of macroentrepreneurial (Van de Veen 1995, Chiles/Meyer 2001) activities in order to facilitate start ups and to support the first steps of a new business from its start to its growth. The value of the incubator model as an effective means of technology and knowledge transfer especially from universities is continually discussed and questioned (Cunningham 1999). For example, a study run by Allen and Kahman (1985) concluded that incubators are tools for developing enterprises which create a positive environment for small businesses to succeed. Indeed, lots of studies brought up that incubators are an efficient and effective way to sustain spin-out processes and to contribute to regional development and prosperity. However, on the other hand some shortcomings are obvious: Finer and Holberton (2000) take into question the incubator model because it takes the initiative away from the start-up team. The paper refers to these observations. We assume by means of some international empirical studies that the functions of incubators are enhanced as a result of a (evolutional) learning process. On this basis we derive hypothesis about the dealing with the upcoming challenges and provide further research questions in an explorative way. Paragraph 2 introduces a three phased model of business incubators and classifies existing incubators. It will be obvious, that there is an increasing amount of functions that are allocated by incubators. Within paragraph 3 we examine recent developments from a macroeconomic perspective and contrast to this the evolution of incubators. Paragraph 4 presents two types of incubators that take these
40

Masterplan „Digitale Verwaltung Sachsen“: Überblick

12 August 2020 (has links)
Der Masterplan »Digitale Verwaltung Sachsen« ist das Regierungsprogramm zum Ausbau der elektronischen Verwaltung im Freistaat Sachsen. Die beiden Kernziele sind, dass bis Ende 2022 alle Verwaltungsleistungen gemäß OZG-Umsetzungskatalog elektronisch zur Verfügung stehen und dass alle Verwaltungsverfahren soweit wie möglich innerhalb der Verwaltung durchgängig elektronisch bearbeitet werden. Redaktionsschluss: 14.03.2019

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