Auf der Grundlage technischer, wirtschaftlicher und ökologischer Kriterien werden drei Prototypen unterschiedlicher Anwendungen in Holz- und Metallbauweise untersucht und deren Unterschiede bewertet. / Based on technical, economic and ecological criteria, three prototypes of different applications in wood and metal construction are examined and their differences are evaluated.

In order to investigate the etiology of and evaluate interventions for work-related back injuries, researchers need efficient, accurate occupational exposure assessment methods suitable for large samples. The chapters in this thesis examine critical decisions using electromyography (EMG): How should exposure be measured? For what duration? Who should be measured, and how many times? Low-back EMG, or muscle activity data, was collected during 138 full-shift field measurements over 30 different job titles at 50 different worksites in 5 heavy industries: forestry, transportation, wood products, construction, and warehousing. Observations and self-reports of posture, manual materials handling (MMH), and driving exposures were collected concurrently. 1) Variability of EMG calibration measurements was investigated on right/left sides, multiple trials, 4 positions, and pre/post-shift. Position accounts for the majority of explained variability; there is little to gain by measuring multiple trials or pre- and post-shift, but measuring both sides and multiple positions is worthwhile. 2) Observation and self-report data were easier to collect and cheaper than the EMG direct measure. Costs and successful field performance need to be weighed against the added data detail when making choices about exposure assessment techniques for epidemiological studies. 3) Observed and self-reported exposures were used to predict EMG exposure metrics using mixed multiple linear regression models. Regression models using observed variables predicted 43-50% of the variability in the EMG metrics, while self-reported variables predicted 21%-36%. The observation exposure model provides a low-cost alternative to direct measurement. The self-reported exposure model should be considered with more caution. 4) Full-shift EMG data was resampled for 4, 2, and 1 hour, and for 10 and 2 minute durations to determine the optimal sampling duration. Bias was consistently low, but shorter durations had higher absolute error, percentage error, and limits of agreement. Durations of 4 and 2 hours may be acceptable but those less than 1 hour had large errors. 5) Components of EMG variance were calculated between- and within-subject, and between- industry, company, job, and post hoc grouping. Resolution, contrast, and exposure-response relationship attenuation were calculated for each grouping scheme. The post hoc scheme had the highest contrast and lowest resolution. / Medicine, Faculty of / Population and Public Health (SPPH), School of / Graduate

This diploma project drala with the solution of manipulation with plywood for the Iveco Czech Republic a.s. bus floor production. Project considers just a manipulationby the CNC cutter. Evaulating of the recent Metod of manipulation, the suggestion of the new Metod of manipulation and the preparation of the possible variants. Evaulating of the variants and probably the suggestion of the new workplace arrangement.

Nachwachsende Rohstoffe stellen in zunehmendem Umfang eine sinnvolle Alternative zu herkömmlichen Konstruktionswerkstoffen im Maschinen- und Anlagenbau dar. Speziell Lagenholzwerkstoffe bieten enormes Potential, den Anforderungen an Nachhaltigkeit und Ressourceneffizienz gerecht zu werden, ohne auf eine entsprechende technische Leistungsfähigkeit verzichten zu müssen. In diesem Zusammenhang wird im Vortrag ein an der Technischen Universität Chemnitz entwickeltes Konzept vorgestellt, Metallwerkstoffe (Stahl und Aluminium) im Maschinenbau durch nachwachsende Rohstoffe zu substituieren. Am Beispiel eines in der Automobilproduktion eingesetzten Fördersystems aus Holzwerkstoff wird dieses Konzept erläutert. Dabei handelt es sich um ein im Karosserierohbau bei Volkswagen verwendetes Skidfördersystem. Anhand einer Anforderungsliste wird im Vortrag schwerpunktmäßig der konstruktive Aufbau des Förderers vorgestellt, wobei vor allem die Unterschiede und Besonderheiten zur herkömmlichen Metallbauweise im Vordergrund stehen. Die Berechnung und Auslegung der Transporteinheit erforderte besondere Rechenmodelle, die für die verwendeten Insertverbindungen hergeleitet wurden und im Vortrag kurz erläutert werden. Speziell das dynamische Anforderungsprofil der Anwendung an die Struktur sowie die Verbindungstechnik ist durch bekannte Berechnungsgrundlagen (Bauwesen, Eurocode 5) nicht abgedeckt. Aus diesem Grund werden dem Maschinenbau entstammende Dauerfestigkeitsbetrachtungen speziell für Verbindungen des Ingenieurholzbaus genutzt. Zum Abschluss des Vortrages wird auf den mittlerweile eineinhalb jährigen, störungsfreien Praxiseinsatz bei der Volkswagen AG in Wolfsburg eingegangen und die Vorteile zum herkömmlichen Stahlfördersystem aufgezeigt. / Renewable resources become more and more a useful alternative to conventional construction materials in machine and plant construction. Especially wood veneer composites offer an enormous potential to meet the requirements of sustainability and resource efficiency without having to give up appropriate technical and mechanical capabilities. In this context the University of Technology in Chemnitz has developed a concept to replace metal materials such as steel or aluminum in mechanical engineering by renewable resources. A skid conveyor system made of wood veneer composites in automotive production used by Volkswagen will give a further explanation of this concept. Based on a list of requirements the lecture focuses the structural design. Especially the most notably differences and peculiarities to the conventional metal construction will be shown. The calculation and dimensioning required special calculation models, which have been derived for the used insert joints. Especially the dynamical requirement specifications of the application concerning the structure itself and the joints are not covered by computational models from civil engineering (Eurocode 5). Therefore fatigue strength examinations originated from mechanical engineering were adapted for joints usually used in timber engineering. The speech closes by summarizing the 18 month failure-free operation of totally five conveyor units at Volkswagen in Wolfsburg as well as their advantages compared to the conventional steel conveyor system.

Im Projekt wurde die Substitution von Metallen durch Holzwerkstoffe in drei ausgewählten Anwendungsfällen untersucht. Es wurde ein Arbeitstisch mit Nutenplatte, ein Schlitten für einen Rollenprüfstand und ein Vertikalförderer in Metallbauweise subsituiert. Die resultierenden drei Holzbauweisen wurden als Prototyp realisiert. Ein Vergleich der Bauweisen zeigt technische, ökonomische und ökologische Vorteile sowie Grenzen der Holzbauweisen. Förderkennzeichen: 22023611 bzw. 11NR236 / The substitution of three applications made from metals using wooden materials was the objective of the project. A workbench with a slotted table top, a sliding carriage for a roller test bench and a vertical conveying system have been substituted. As a result, three wood constructions were realized as prototypes. A comparison of the constructions shows technical, economical and ecological advantages as well as limits of the wood design itself.

This dissertation focuses on the material transport system design problem (MTSDP), integrating decisions of technology selection and flow network design. This research is motivated by the design of material transport systems (MTS) in manufacturing plants. The objective is to design a MTS with minimum lifetime costs, subject to service requirements, flow network restrictions, and limited resources. We characterize the MTSDP from the perspectives of task requirements, transport technology, and space utilization. A classification is proposed for transport technologies such that instances in the same class share the same properties, and a decision framework is proposed to emphasize the inter-relationships of three major decisions: task clustering, network connecting, and technology selection. We consider fixed and variable costs, arc capacities, and empty travel in our formulations. We propose two solution approaches for the MTSDP. The first is the compact formulation (CF) approach where the three major decisions are handled by a mixed integer non-linear programming (MINLP) formulation. Relaxation techniques are applied to linearize the model. The solution of the resulting linear formulation (MILP) provides a lower bound to that of MINLP. A tightened formulation reduces the computational time by a factor of 3.85. The experiment also shows that when control system costs are significant, designs with multiple-task clusters are more economical than those restricted to single-task clusters. The other approach is clustering/set partition (CSP), where the three decisions are decomposed and solved sequentially. In an example MTS design problem, three methods are compared: CSP, a GREEDY approach from the literature, and enumeration. CSP finds the optimal solution, while GREEDY results in 31% greater costs. A similar comparison with another example is made for the CF and CSP approaches. We apply the CSP approach in a case problem, using data from an auto parts manufacturer. We include flow path crossing constraints and perform experiments to determine solution quality over a range of small problem sizes. The largest difference from optimality is 3.34%, and the average is 0.98%. More importantly, based on these experiments, it seems there is no evidence that the difference percentage grows with an increase in the number of tasks.

Made available in DSpace on 2016-06-02T20:19:19Z (GMT). No. of bitstreams: 1 4746.pdf: 1426086 bytes, checksum: f41b8c37c91b06ab62579658c926ad62 (MD5) Previous issue date: 2012-11-20 / Universidade Federal de Sao Carlos / With the rapid development of civil aviation in Brazil there was a large number of subjects involved in the aircraft maintenance work. Much of workers develop tasks involving manual material handling (MMH), which already have evidenced musculoskeletal risks. However, workers from the aircraft maintenance industry suffer huge pressure due the safety issues and the quality of the work that is performed. There were no studies in the literature that addressed the risk factors present in this sector. Thus, the aim of Study 1 was to evaluate the psychosocial indicators, as well as reports of musculoskeletal symptoms and disorders among workers iof the aircraft maintenance industry. One hundred and one employees were assessed using the Nordic Musculoskeletal Questionnaire, a standardized physical examination, the Job Content Questionnaire and the Utrecht Work Engagement Scale. The results indicate that the workers are exposed to good psychosocial conditions, which have neither prevented the emergence of musculoskeletal disorders, nor the self reported pain and functional disability, particularly associated with the lower back. As the MMH was the main activity performed by the aircraft maintenance workers assessed, musculoskeletal disorders seem to be associated with the biomechanical characteristics of this activity. Despite the risks already identified, the literature suggests some strategies for reducing the physical load imposed to the musculoskeletal system during MMH. These strategies such as the implementation of handles on boxes, ensuring better coupling object/hands during handling. However, the recommendations of adaptations in boxes are not conclusive regarding handle placement, and their impact on workers' musculoskeletal conditions. Thus, the Study 2 was conducted based on a systematic literature review. The aim was to synthesize evidence regarding the effect of adjustment on boxes, aiming at reduction of musculoskeletal load. A survey was conducted in the following databases: Embase, Pubmed / Medline, Web of Science, and Lilacs Bireme CINAHAL, Sportdiscuss, Cochrane. Two reviewers independently selected the relevant studies, and any disagreements were solved by consensus. Cross-sectional studies were included. The scale proposed by Ariens (2000) was used to assess the quality of the studies included in this review. The electronic search yielded a total of 1170 references published in English. At the end of the selection process, and after manual search of references, the selection included 15 cross-sectional studies. Due to do the great methodological variability, regarding both methods and the proposed adaptations (size and mass of boxes), associated with the low quality of the studies prevented the synthesis of evidence. There is a need of using objective and subjective methods to evaluate standardized boxes with handles, which can also be applied to the assessment of other ergonomic interventions. Furthermore, the handles should be investigated using various positions and inclinations, and the MMH has to be carried out to different heights, in order to provide more conclusive evidence to support the implementation of those adaptations in the occupational practice. Experienced subjects have also to be considered in future studies. / Com o desenvolvimento acelerado da aviação civil no Brasil observou-se um elevado número de sujeitos envolvidos com o trabalho de manutenção de aeronaves. Grande parte dos trabalhadores desenvolvem tarefas que envolvem a realização do manuseio de cargas, o qual já tem grandes evidências de riscos musculoesqueléticos. No entanto, o setor de manutenção de aeronaves sofre grandes pressões com a segurança e com a qualidade do trabalho realizado. Não foram encontrados na literatura estudos que abordassem os fatores de risco presentes neste setor. Dessa forma, o Estudo 1 teve como objetivo avaliar os indicadores psicossociais, assim como os relatos de sintomas musculoesqueléticos entre trabalhadores do setor de manutenção de aeronaves. Cento e um funcionários foram avaliados por meio do Questionário Nórdico de Sintomas Osteomusculares, por uma avaliação física padronizada e pelas Escala de Estresse e Trabalho e a Escala de Bem Estar e Trabalho. Os resultados indicam que trabalhadores da indústria de manutenção de aeronaves envolvidos com tarefas de manuseio de materiais são expostos a boas condições psicossociais, o que não impediu o surgimento de distúrbios musculoesqueléticos, nem o alto índice de relato de dor e incapacidade funcional, particularmente associado com a parte inferior da coluna. Como o manuseio de materiais foi a principal atividade realizada no setor de manutenção de aeronaves avaliado, os distúrbios musculoesqueléticos encontrados foram associados às características biomecânicas desta atividade. Apesar dos riscos já identificados, a literatura aponta algumas estratégias para redução da carga física imposta ao sistema musculoesquelético durante o manuseio de cargas. Tratam-se de estratégias nos instrumentos de trabalho, como a implementação de pegas em caixas, garantindo melhor acoplamento objeto/mãos durante o manuseio. No entanto, as adaptações em caixas não são conclusivas em relação às recomendações de posicionamento e sua repercussão nas condições musculoesqueléticas dos trabalhadores. Desta forma, foi realizado o Estudo 2 desta dissertação a partir de uma revisão sistemática da literatura. O objetivo foi sintetizar evidências em relação ao efeito da adaptação de caixas na redução da carga musculoesquelética. Foi realizada pesquisa nas seguintes bases de dados: dados Embase, Pubmed/Medline, Web of Science, Bireme e Lilacs CINAHAL, Sportdiscuss, Cochrane. Dois revisores independentes selecionaram os estudos pertinentes, e as eventuais discordâncias foram solucionadas por consenso. Foram incluídos estudos tranversais. A escala proposta por Ariens (2000) foi utilizada para avaliação da qualidade dos estudos incluídos nesta revisão. A busca eletrônica resultou em um total de 1170 referências publicadas em inglês. Ao final do processo de seleção e da busca manual das referências dos artigos inicialmente incluídos na revisão, totalizou-se a seleção de 15 estudos transversais. A grande variabilidade metodológica, tanto em termos de avaliação como em relação às formas de adaptação de pegas propostas, tamanho e massa das caixas, associadas à baixa qualidade dos estudos incluídos, inviabilizou o agrupamento dos estudos para síntese de evidência. Observa-se a necessidade da utilização conjunta de metodologias objetivas e subjetivas padronizadas na avaliação de caixas adaptadas com pegas, o que pode ser estendido para outros tipos de intervenções ergonômicas. Além disso, as caixas adaptadas precisam ser investigadas a partir de diferentes posicionamentos e inclinações das pegas, a serem manuseadas em diferentes alturas, para fornecer evidências mais definitivas para a implementação na prática ocupacional. A questão da experiência dos sujeitos avaliados também deve ser considerada em estudos futuros.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T13:51:24Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T13:51:24Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T13:51:24Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T13:51:24Z (GMT). No. of bitstreams: 0 / Neste trabalho foram estudadas as series de ligas La0,7Mg0,3Al0,3Mn0,4Co(0,5-x)NbxNi3,8 (x =0 a 0,5) e La0,7Mg0,3Al0,3Mn0,4Nb(0,5-x)Ni(3,8-x) (x =0,3; 0,5 e 1,3), como eletrodo negativo de baterias de Níquel Hidreto Metálico. A pulverização das ligas foi realizada com duas pressões de H2 (2 bar e 9 bar). A capacidade de descarga das baterias de níquel hidreto metálico foi analisada pelo equipamento de testes elétricos Arbin BT-4. As ligas, no estado bruto de fusão, foram analisadas por microscopia eletrônica de varredura (MEV), espectroscopia de energia dispersiva (EDS) e difração de raios-X. Com o aumento da concentração de nióbio nas ligas nota-se a diminuição da estabilidade cíclica das baterias e da capacidade máxima de descarga. A capacidade de descarga máxima obtida foi para a liga La0,7Mg0,3Al0,3Mn0,4Co0,5Ni3,8 (45,36 mAh) e a bateria que apresentou a melhor performance foi a liga La0,7Mg0,3Al0,3Mn0,4Co0,4Nb0,1Ni3,8 (44,94 mAh). / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Marco Antonio Oliveira da Silva (maosilva@ipen.br) on 2016-12-22T12:40:27Z No. of bitstreams: 0 / Made available in DSpace on 2016-12-22T12:40:27Z (GMT). No. of bitstreams: 0 / Foram estudados as propriedades de absorção ótica, de termoluminescência e de ressonância paramagnética eletrônica do mineral natural de silicato de nome MONTICELITA do grupo Olivina, para caracterização desse mineral, cuja formula química é CaMgSiO4. A absorção ótica mostrou que há três bandas de absorção em 450 nm, 660 nm e 1050 nm. As duas primeiras bandas, a primeira no azul e a segunda no amarelo-vermelho são responsáveis pela cor verde da Monticelita. Essas duas bandas são consequência do elemento cromo contido no mineral absorver fótons do feixe universal no visível de frequências centradas em 450 nm e 660 nm. A banda em 1050 nm é devido ao Fe2+. As curvas de emissão de uma amostra de Monticelita irradiada com raios gama de doses entre 10 e 1000 Gy apresenta três picos em 150 °C , 270 °C e 370 °C . Pelo método da deconvolução e de várias taxas de aquecimento foram obtidos energia E1=1,35 eV e fator de frequência s1=4,98x1011 s-1 para o pico 270 °C e E2=1,70 eV e s2=1,88x1011 s-1 para pico 370 °C . A irradiação com raios gama de doses entre 5 kGy e 50 kGy produziram pico TL de 380 °C com intensidade TL em função da dose linear e crescente. Este resultado e importante para dosimetria da radiação de altas doses. O espectro EPR de uma amostra natural, mostrou um resultado não esperado e interessante. Além dos sinais típicos de interação hiperfina do Mn2+, um sinal avantajado de g =6,34 indica que o ferro formou moléculas de hematita, Fe2O3. Esse sinal desaparece com aquecimento acima de 800 °C de recozimento, dando origem dipolos magnéticos de Fe3+, que dá origem a um sinal típico em g =2. Esta descrição mostra bem a caracterização do mineral Monticelita. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP