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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

Analys av interna transporter och buffertlager vid Vest-Wood Sverige AB

Reis, Fredrik, Carlsson, Erik January 2007 (has links)
Denna rapport är resultatet av en analys som gjorts vid Vest-Woods fabrik i Forserum under våren 2007 i syfte att reducera interna transporter. Vest-Wood AB i Forserum tillverkar dörrar för den svenska marknaden men förser också en annan fabrik (Sdr Felding i Danmark) i samma koncern med dörrstommar. Materialhantering för att förse Sdr Felding fabriken med dörrstommar medför i dagsläget mycket interna transporter i Forserumsfabriken. För att klara ojämn efterfrågan från Sdr Felding fabriken samt för att kunna jämna ut sin egen produktion har Forserumsfabriken valt att lagerföra de tolv artiklar som beställs mest frekvent från Sdr Felding fabriken. Buffertlagret vid Forserumsfabriken där artiklarna lagerförs är placerat ca 200 m från produktionen vilket medför mycket intern transport för hantering av dessa. Uppgiften som Vest-Wood AB i Forserum ville ha analyserad var hur de kunde hitta ett mer ekonomsikt fördelaktigt upplägg av de interna transporterna inom fabriken i Forserum. För att kartlägga nuläget beräknades medelvärdet av buffertlagret baserat på inventerade lagersaldo från 2006. I samma buffertlager lagerförs den buffert som skall täcka efterfrågan för den veckas extra semester som Forserumsfabriken har jämfört med Sdr Felding fabriken. Den semesterbufferten fick räknas bort. Efter att ha fastställt medelvärdet på buffertlagret kunde lagerhållningskostnaden beräknas. I den del av Forserumsfabriken som vi analyserat sker tillverkning i tre flöden där de tolv lagerförda dörrstommarna tillverkas i två av dem. Vi räknade ut att total kapacitet i dessa båda och fann att det finns en möjlig extra kapacitet på 25 %. Med medelvärdet och möjlig extra kapacitet som underlag kunde ett förbättringsförslag tas fram. Förbättringsförslaget handlar om att ta bort buffertlagret, som ett led i att minska de interna transporterna. Förbättringsförslaget förutsätter att samarbetet och insynen mellan fabriken i Sdr Felding och fabriken i Forserum förbättras. / This report is the result of an analysis made at Vest-Woods factory in Forserum during the spring of 2007 with the purpose to reduce internal transports. Vest-Wood AB in Forserum produces doors for the Swedish market but is also a supplier of doorframes to another factory (Sdr Felding in Denmark) in the same group of companies. The material handling for supplying the factory in Sdr Felding with doorframes causes a lot of internal transports. The factory in Forserum has chosen to keep the twelve most ordered doorframes in stock to keep up with varying demand from the factory in Sdr Felding and to smooth their own manufacturing. The warehouse in Forserum, where the doorframes are stored, is placed 200 m from the manufacturing site and that contributes to the internal transport. The assignment that Vest-Wood AB in Forserum wanted analysed was how they could find a more beneficial arrangement of the internal transports from an economic point of view. To define the present situation we calculated the mean value based on inventory data from 2006. The factory in Forserum is closed for one more week than the factory in Sdr Felding is during the summer. For that reason, a buffer is built to cover the demand from the factory in Sdr Felding during this week. This buffer is also kept in the warehouse. That buffer was subtracted from the inventory results. When the mean value of the warehouse had been calculated, the yearly cost of storing the doorframes could be calculated. There are three different flows in that part of the factory in Forserum where our analysis has taken place. Production of the twelve doorframes takes place in two of them. We calculated total capacity in these two flows and found that they have potential extra capacity of 25 %. With the mean value of the warehouse and the potential extra capacity in the production we could work out a proposal of improvement. The proposal treats how to remove the warehouse as a way of reducing internal transports. The proposal assumes that the collaboration and insight between the factory in Sdr Felding and the factory in Forserum is improved.
112

Fokus på : utveckling av nyckeltal för effektiv internlogistik / Focus on : Development of Key Performance Indicators for Efficient Logistics

Mannerheim, Kristoffer, Pettersson, Martina January 2008 (has links)
Detta arbete inom prestationsmätning av effektiv logistik är utfört på Scanias produktionsenhet MB i Oskarshamn. Denna produktionsenhet tillverkar hytterna till Scanias lastbilar på europamarknaden, från plåtrulle till färdigmålad hyttkaross. Produktionsenheten MB består av en pressverkstad, en karossverkstad och ett måleri. Uppgiften i detta arbete är att utveckla ett antal mätetal för prestationsmätning av MB:s internlogistik, och utifrån dessa ge förslag på förbättringsmöjligheter i verksamheten. Uppgiften löses genom att använda Bourne och Neelys metoder för utveckling av mätetal, så som en framgångskarta för den kritiska framgångsfaktorn effektiv logistik och utformandet av ett definitionsblad, vilket explicit definierar varje mätetal. Detta tillsammans med Parmenters definitioner angående mätetal och arbetssätt vad det gäller prestationsmätning, avser att spegla moderna tillvägagångssätt för prestationsmätning och för implementering av dessa i ett företag. De mätetal som rekommenderas för implementering i MB:s logistiska verksamhet är trucktimmar per hytt, leveranspålitlighet, lageryta, energianvändning per hytt för transporter och materialhanteringskostnad per hytt. Flera förbättringsförslag rekommenderas också vad det gäller den förbättringspotential som finns vid införandet av en gemensam materialhanteringsfunktion på MB. Vidare ges också förslag på system- och rutinförändringar som kan genomföras för att ge mer tillförlitlig information för prestationsmätning och skapa mer effektiv logistik. / This master thesis within performance measurement of logistic efficiency is carried out at the Scania production unit MB in the city of Oskarshamn. This production unit manufactures the cab body to heavy trucks for the European market, from metal coil to painted cab body. The production unit consists of one press shop, one body shop and one paint shop. The mission of the thesis is to develop a few Key Performance Indicators (KPIs) for performance measurement of MB’s logistics and with these KPIs as a base, point out potential improvements at the production unit. The task was fulfilled through the use of Bourne and Neely’s methods for developing KPIs, such as a success map based on the critical success factor, efficient logistics combined with their record sheet for developing and defining each KPI. This together with Parameter’s definition regarding KPIs and guidelines for performance measurement should present a modern approach of how to implement performance measurement in a company. The KPIs which is recommended for implementation in MB’s logistic operations is forklift hours per cab, delivery reliability, storage area, energy consumption by transports per cab and material handling costs per cab. Several improvements are suggested when it comes to the benefits of a common material handling organization which serves all MB operations. Also suggestions are made regarding the information system and routine changes which aim to give more reliable information for performance measurements and as a mean to create more efficient logistics.
113

Ordonnancement de ressources de transports : flow-shops robotisés circulaires et un problème pratique de gestion ferroviaire / Scheduling handling resources : robotic flowshops with circular layout and a practical railway problem

Thiard, Florence 21 November 2017 (has links)
La première partie de ce travail concerne la production cyclique pour l'optimisation du taux de production dans les flowshops robotisés, où un robot est chargé du transport des pièces. Les cellules robotisées peuvent être disposées de façon linéaire ou circulaire. Les principaux résultats théoriques concernant la disposition linéaire ne peuvent être étendus à la configuration circulaire. En particulier, trouver le meilleur cycle de production de une pièce (1-cycle) est un problème polynomial dans le cas des cellules linéaires additives, mais NP-difficile pour la configuration correspondante circulaire.Nous nous concentrons principalement sur le cas des cellules circulaires équilibrées, où le temps d'usinage est identique sur toutes les machines. Après avoir présentés des outils pour l'analyse cyclique dans les cellules circulaires, nous établissons des propriétés nécessaires des 1-cycles performants, ce qui permet de conclure sur le problème du meilleur 1-cycle jusqu'à 8 machines. Toutefois, nous fournissons un contre-exemple pour 6 machines à la conjecture classique des 1-cycles, toujours ouverte dans cette configuration.Ensuite, nous étudions la structure des 1-cycles performants pour des cellules circulaires équilibrées arbitrairement grandes. Nous définissons et étudions les propriétés d'une nouvelle famille de cycles basée sur cette structure et formulons une conjecture sur sa dominance sur les 1-cycles qui conduirait à un algorithme polynomial pour le problème du meilleur 1-cycle dans ce cas. Cette structure permet de déterminer le meilleur 1-cycle jusqu'à 11 machines.Dans la deuxième partie, nous présentons le travail réalisé sur un problème industriel proposé par la SNCF dans le cadre du challenge ROADEF/EURO. Nous proposons un algorithme glouton pour ce problème combinant divers aspects de la gestion des trains au sein d'une gare. / The first part of this work deals with cyclic production for throughput optimization in robotic flow-shops, where a robot is in charge of the material handling of parts. Robotic cells may have a linear or a circular layout. Most theoretical results for the linear layout do not hold for the circular layout. In particular, the problem of finding the best one part production cycle (1-cycle), which is a polynomial problem for linear additive cells, has been proved NP-hard for the corresponding circular configuration.We mainly focus on a special case of circular balanced cells, where the processing times are identical for all machines. After presenting tools for cyclic analysis in circular cells, we study necessary properties of efficient 1-cycles. These results allow to conclude on the best one part production cycle for any parameters in circular balanced cells up to 8 machines. However, we provide a counter-example to the classical 1-cycle conjecture, still open for this configuration.Then, we study the structure of efficient one part production cycles in arbitrarily large circular balanced cells. We introduce and study a new family of cycles based on this structure, and formulate a conjecture on its dominance over one part-production cycles, which would lead to a polynomial algorithm for finding the best 1-cycle for circular balanced cells. This structure allows to settle the best one part production cycle for cells with up to 11 machines.In a second part, we present work on an industrial problem of railway stock scheduling proposed by the French railway company in the context of the ROADEF/EURO competition. We propose a greedy algorithm for this problem combining the various aspects of trains handling inside a station.
114

Ergonomisk kartläggning av internt logistikflöde - Med förbättringsförslag : En fallstudie genomförd på ett företag

Agerskans, Natalie January 2018 (has links)
Syftet: Syftet med denna studie är att kartlägga belastningsergonomiska risker i ett framtida internt logistikflöde, samt att ge förslag på hur dessa risker kan undvikas genom tillämpning av LEAN metodik och en ny logistiklösning. Följande frågeställningar har ställts för att identifiera orsaker till problem och förbättringsmöjligheter: 1)    Vilka arbetsmoment i det studerade logistikflödet leder till ergonomiska risker? 2)    Hur kan fallstudieföretaget införa LEAN metodik för att uppnå bättre ergonomi vid materialhantering? 3)    Hur kan en ny generell och mer ergonomisk logistiklösning för materialhantering se ut på fallstudieföretaget? Metod: Studien har genomförts baserat på en fallstudie på ett industriföretag. Data har samlats in genom intervjuer och observationer på fallstudieföretaget, studiebesök på två andra industriföretag samt genom en litteraturstudie. För att identifiera och bedöma olika ergonomiska risker har verktyget RAMP tillämpats. Studiens resultat: Studien resulterade i en ergonomisk kartläggning för ett utvalt internt logistikflöde med förslag på hur bättre ergonomi kan uppnås i fallstudieföretagets material-hantering. Den ergonomiska kartläggningen påvisade att flera arbetsmoment innebär en ökad risk för att personalen utvecklar belastningsbesvär. Många tunga lyft, skjuta- och dra arbete samt olämpliga arbetsställningar visades ha störst negativ inverkan på ergonomin. För att minska dessa risker utan större förändringar av nuvarande fabrikslayout och befintligt arbetsflöde kan bland annat arbetsrotation, olika hjälpmedel och modifieringar av teknisk utrustning införas. Förslag presenteras också på hur en ny och mer ergonomisk materialhanteringslösning kan se ut på fallstudieföretaget genom införande av en omplockningsstation och en supermarket. Även ett förslaget ramverk presenteras för hur fallstudieföretaget kan arbeta genom LEAN-metodik i syfte att uppnå en bättre ergonomi i materialhanteringen. Slutsats: Den ergonomiska kartläggningen indikerade att förbättringsåtgärder krävs för att personal inte ska riskera att utveckla belastningsbesvär och förslag har tagits fram för hur den ergonomiska situationen kan förbättras. Rekommendationer: Fallstudieföretaget rekommenderas att vidta åtgärder för de ergonomiska risker som har identifierats. Innan de föreslagna förbättringarna fullföljs krävs vidare studier för att utvärdera förbättringsförslagen ur andra än ergonomiska aspekter samt genomförande av RAMP-analys. Fallstudieföretaget rekommenderas även att undersöka möjligheten att införa det föreslagna LEAN-ramverket i syfte att skapa förutsättningar för en god ergonomisk situation. Nyckelord: Belastningsergonomi, RAMP, Omplockningsstation, Arbetsmiljö, Intern logistik, Materialhantering / Purpose: The purpose of this study is firstly to identify risks of ergonomic strain in a future internal logistics flow and secondly propose how to avoid these risks by applying LEAN methodology and a new logistics solution. In order to identify causes for problems and to find improvement opportunities the following issues have been addressed: 1)    What tasks in the studied logistics flow lead to risks of ergonomic strain? 2)    How can the studied company implement the LEAN methodology to improve ergonomics in the material handling? 3)    How can a new general and more ergonomic logistic solution for material handling look like for the studied company? Method: The study has been conducted based on a case at an industrial company. Data has been collected through interviews and observations at the company, visits at two other industries and through a literature survey. To identify and assess various ergonomic risks, the RAMP tool has been applied. Study result: The study resulted in an ergonomic survey for a selected internal logistics flow with suggestions on how to improve ergonomics in the studied company´s material handling. The ergonomic survey showed that several work tasks cause an increased risk for the operators to develop strain injuries and therefore improvements are required. Heavy lifting, pulling and sliding work pieces and incorrect working positions were shown to have the most adverse impact on good ergonomics. To reduce these risks - without major changes to the current factory layout and existing workflow - work rotation, various tools/aids and modifications of technical equip-ment can be implemented. Proposals are presented on how a new and more ergonomic material handling solution can be achieved at the studied company through the introduction of a pickup station and a “supermarket”. A suggested framework is also presented for how the company can use LEAN methodology in order to achieve better ergonomics in the material handling process. Conclusion: The ergonomic survey indicated that improvements are required in order not to risk strain injuries for the operators. Suggestions have been made for how the ergonomic situation can be improved. Recommendations: The studied company is recommended to take measures with respect to the ergonomic risks identified. Before the proposed improvements can be introduced, studies are required to evaluate the improvement proposals from other than ergonomic aspects as well as performing a RAMP analysis. The studied company is also recommended to investigate the possibility of introducing the proposed LEAN framework. Keywords: Strain ergonomics, RAMP, Picking station, Work environment, Internal logistics, Material handling
115

Effektivisering av materialflödet i inlagringsprocessen i ett distributionslager : Genom exkludering av begränsningar / A study about how a distributioncenter´ inbound process can get more efficient.

Ramde, Sara, Qadir, Lana January 2018 (has links)
Syfte – Syftet med studien är att identifiera kritiska begränsningar i inlagringsprocessen i ett distributionslager för att därmed kunna effektivisera materialflödet. Studiens syfte uppnås genom att följande forskningsfrågor har formulerats: Vilka kritiska begränsningar kan förekomma i materialflödet i en inlagringsprocess i ett distributionslager? Hur kan de identifierade begränsningarna exkluderas i en inlagringsprocess? Metod – Studien hade en induktiv ansats och datainsamling skedde genom intervjuer, observationer, dokumentstudier och litteraturstudier. En fallstudie genomfördes på ett distributionslager och empiri och teori har jämförts för att kunna uppfylla studiens syfte. Resultat – Studiens resultat påvisar att de förekommande kritiska begränsningarna i ett distributionslager är brist på yta, materialhantering, automatiska system samt lagerlayout. Studiens slutsats är att begränsningarna är sammankopplade och påverkar varandra eftersom de ingår i samma process. För att exkludera begränsningarna bör distributionslager implementera diverse standarder i sin inlagringsprocess och arbeta med ständiga förbättringar. Implikationer – Studien bidrar inte med nya teorier men bidrar med praktisk nytta för distributionslager med liknande kriterier som studiens fallföretag. Begränsningar – Studien riktar enbart in sig på distributionslager och var en fallstudie av enfallsdesign. Genom att utföra flera liknande undersökningar på företag med liknande kriterier hade generaliserbarheten kunnat stärkas. / Purpose – The purpose of the study is to identify critical constraints in the inbound process at a distribution warehouse. To accomplish the purpose two research questions were formulated: Which critical constraints can occur in the material flow in the inbound process at a distribution warehouse? How can the identified constraints be excluded in the inbound process? Method – The study was performed inductively, and the data collection techniques were interviews, observations, document studies and literature studies. A single case study was performed at a distribution warehouse and the empirical data and theories were compared to accomplish the purpose of the study. Findings – The result of the study demonstrates that the critical constraints in the inbound process at a distribution warehouse are space, material handling, automatic systems and warehouse layout. The conclusion of the study is that the constraints are connected and affect each other since they are all included in the same process. To exclude the constraints different types of standards should be implemented in the inbound process, and distribution warehouses should work with continuous improvements. Implications – The study does not contribute to new theories but can be practically beneficial for distribution warehouses similar to the studies case study. Limitations – The study only focuses on one distribution warehouse and is therefore a single case study. The generalizability could have been higher if the study had been conducted at multiple distribution warehouses.
116

Abastecimento de materiais numa linha de montagem final multiproduto / Material supply in multiproduct final assembly line

Rodrigues, Márcio Garcia [UNESP] 21 April 2016 (has links)
Submitted by MÁRCIO GARCIA RODRIGUES null (marciogarcia@maxionsc.com) on 2016-04-28T15:54:31Z No. of bitstreams: 1 Dissertacao_Marcio Garcia_280416.pdf: 2456536 bytes, checksum: b79ef40cb702a054ccb7d7f939704cf6 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-02T12:54:04Z (GMT) No. of bitstreams: 1 rodrigues_mg_me_guara.pdf: 2472389 bytes, checksum: 1c7d0b1b7f5b2d9c139a65d762cda63a (MD5) / Made available in DSpace on 2016-05-02T12:54:04Z (GMT). No. of bitstreams: 1 rodrigues_mg_me_guara.pdf: 2472389 bytes, checksum: 1c7d0b1b7f5b2d9c139a65d762cda63a (MD5) Previous issue date: 2016-04-21 / A crescente variedade de produtos nos sistemas atuais de produção é um grande desafio para a logística interna de abastecimento de materiais numa linha de montagem final, o abastecimento logístico precisa estar em concordância com a programação de produção de forma a disponibilizar para montagem o material necessário, no momento certo e na quantidade correta. A linha de montagem objeto do estudo acompanha esta tendência. Nela são montados modelos variados de chassis. Desta forma, o objetivo geral da pesquisa é desenvolver um modelo de abastecimento para linha de montagem multiprodutos, onde o ponto principal do trabalho é a definição do conceito mais adequado de acordo com o tipo e quantidade do material a ser abastecido. Através de uma pesquisa-ação foi proposto um modelo de abastecimento de linha que demonstrou uma redução de aproximadamente 50% da área ocupada na borda de linha, em consequência da redução de materiais, e aumento de 3% da produtividade, em virtude das reduções das indisponibilidades e perdas por set-up de abastecimento. / The increasing variety of products in current production systems is a big challenge for internal logistics supply of materials to a final assembly line, the logistic supply must be in step with the production program, in order to provide the necessary material for assembly at the right time and in the correct quantities. The assembly line which is the object of this study follows the trend. On it, several models of chassis are assembled. Therefore, the general objective of this research is to develop a supply model for a multi-product assembly line, with the main focus of the work on determining the most suitable concept in terms of the type and amount of material to be supplied. Through research-action, a model to supply the line has been proposed, which demonstrated a reduction of approximately 50% of the area occupied alongside the line, due to the reduction in materials, and an increase of 3% in productivity, owing to the reductions in outages and losses during supply set-up.
117

Análise das estratégias de movimento adotadas durante a realização de manuseio de carga.

Carregaro, Rodrigo Luiz 02 February 2007 (has links)
Made available in DSpace on 2016-06-02T20:19:04Z (GMT). No. of bitstreams: 1 DissRLC.pdf: 4124701 bytes, checksum: 7ad00279ff99c72a1e55ee44b80f553a (MD5) Previous issue date: 2007-02-02 / Financiadora de Estudos e Projetos / Despite recent technological advances, occupational activities of manual nature are still essential in many sectors and industries. Such activities impose risky conditions, which are inherent to its nature and can be responsible for musculoskeletal injuries. In addiction, the complexity and the interaction of risk factors, many still not comprehended, that act together during the performance of manual material handlings confer challenges and stimulations to the preventive approach. In this way, two main studies (Studies I and II) and two unfolding studies had been carried through. The main studies contextualized the hamstrings flexibility and its influence on the performance of occupational tasks. The objectives of Study I had been to compare the results of two clinical tests used to evaluate hamstrings flexibility and to evaluate the reliability of the photogrammetric procedure adopted for the analysis. The fingertip-to-floor test and straight leg raise test were applied in 35 healthy male subjects. Based on tests results, subjects were divided into two groups: normal and reduced flexibility. Superficial anatomical landmarks were fixed on bony references by means of manual palpation in order to permit the tracing of the hip, thoracic-lumbar, leg, knee and tibio-tarsal angles. The student t test was applied to evaluate the differences between the two groups, for each variable. Findings showed that hip angle was significant lower at the reduced flexibility group and that the straight leg raise test was more sensible for detecting subjects with reduced flexibility. The aim of Study II was to evaluate the influence of hamstrings flexibility on the movement strategy of the trunk and pelvis adopted by healthy subjects during the performance of the manual handling. Subjects were divided into two groups, based on the straight leg raise test. A JVC digital camera with a sampling of 50 frames/second and positioned perpendicularly to the sagittal plane of the subjects was used to register the activity. The cross-correlation coefficient was used to quantify movement patterns relationship between groups, and the student t test applied to the movement variables in order to determine differences between groups. The results had demonstrated that subjects with reduced flexibility used a lesser pelvic amplitude and bigger amplitudes of the trunk during handling. Still, subjects with reduced flexibility adopted a retroverted movement of the pelvis, without great alterations during the activity. The unfolding studies contextualized the comparison of the strategies adopted by subjects with experience in load handling activities and inexperienced individuals. The Study III had as objective to evaluate the manual handling performed by 16 experienced subjects and 15 inexperienced ones. It was used a flexible electrogoniometer to measure trunk movements and the University of Michigan 3D software to estimate the intradiscal compression in L5/S1 during the handling. The normalized movement patterns were evaluated and the coefficient of variation was applied to quantify the variability of this movement. The student t test determined the differences between variables. Results pointed out to great variability of adopted postures. Smaller amplitudes of flexion had been found, but bigger amplitudes of trunk extension when the loads were deposited, respectively, in low and high surfaces for experienced individuals. Experienced subjects presented lower intradiscal compression during box deposition and the lowering task was characterized by the highest intradiscal compression. Study IV aimed to compare manual handling strategies adopted by experienced and inexperienced subjects with relation to the positioning of the feet and trunk during lowering and inclination of the box during lowering and lifting activities. Ten experienced workers and 10 subjects without professional experience with the handling activity had been selected. The manual handling carried out between different heights was filmed. By means of one edition software, the images referring to the instant of 50% of the task had been selected and used to classify the postures and to measure the inclination of the box. An ANOVA with 3 factors was used to evaluate the inclination of the box with relation to the experience, handled load and type of handling (lifting and lowering). The results had indicated that subjects with professional experience adopted strategies characterized by biggest inclination of the box and adoption of balanced postures of the trunk, with widening of the support base. Professional experience determined the adoption of different movement strategies, when compared to inexperienced ones, in response to task conditions. However, other studies are suggested in order to determine if such strategies were protective or risky ones. The results presented in this dissertation raise the hypothesis that hamstrings flexibility is a risk factor for the increase of trunk overload, during the performance of manual material handling. / Apesar dos recentes avanços tecnológicos, as atividades ocupacionais de natureza manual ainda são imprescindíveis e amplamente utilizadas em muitos setores e indústrias. Tais atividades impõem condições de risco, que são inerentes à sua natureza e podem ser responsáveis por lesões músculo-esqueléticas. Em adição, a complexidade e a interação de fatores de risco, muitos ainda não totalmente compreendidos, que atuam em conjunto durante a realização do manuseio de materiais conferem desafios e estímulos à abordagem preventiva. Deste modo, foram realizados dois estudos principais e dois estudos decorrentes das pesquisas direcionadas ao estudo do manuseio de carga. Os estudos principais (Estudos I e II) contextualizam a flexibilidade dos músculos isquiotibiais e sua influência na performance de tarefas ocupacionais. Os objetivos do Estudo I foram comparar os resultados de dois testes clínicos utilizados para avaliar a flexibilidade dos músculos isquiotibiais e avaliar a confiabilidade do procedimento fotogramétrico utilizado. Os testes de Dedos ao Chão e Elevação dos Membros Inferiores (MMII) em Extensão foram aplicados em 35 sujeitos sadios do gênero masculino. Com base nos resultados dos testes, os sujeitos foram divididos em dois grupos: flexibilidade normal e reduzida. Marcadores superficiais refletivos foram fixados em referências ósseas por meio da palpação para permitir o traçado dos ângulos do quadril, tóraco-lombar, perna, joelho e tíbio-tarsico. Aplicou-se o teste t de student para avaliar as diferenças de cada variável entre os dois grupos. Os achados demonstraram que o ângulo do quadril foi significativamente menor no grupo com flexibilidade reduzida e o teste de Elevação dos MMII foi mais sensível para detectar sujeitos com redução de flexibilidade. O objetivo do Estudo II foi avaliar a influência da flexibilidade dos músculos isquiotibiais na estratégia de movimento do tronco e pelve adotada por sujeitos sadios durante a realização do manuseio de carga. Os sujeitos foram divididos em dois grupos, com base na aplicação do teste de Elevação dos MMII. Uma câmera digital JVC com amostragem de 50 quadros/segundo e posicionada perpendicularmente ao plano sagital dos sujeitos foi utilizada para registrar a atividade. O coeficiente de correlação cruzada foi utilizado para quantificar a relação dos padrões de movimento entre os grupos, e o teste t de student aplicado nas variáveis de movimento para determinar as diferenças entre grupos. Os resultados indicaram que sujeitos com flexibilidade reduzida utilizaram uma menor amplitude pélvica e uma maior amplitude do tronco durante o manuseio. Ainda, sujeitos com flexibilidade reduzida adotam movimento em retroversão da pelve, sem grandes alterações ao longo da atividade. Os desdobramentos (Estudos III e IV) contextualizaram a comparação das estratégias adotadas por sujeitos com experiência no manuseio de cargas e por indivíduos inexperientes em tais atividades. O Estudo III teve como objetivo avaliar o manuseio realizado por 16 sujeitos experientes e 15 inexperientes. Utilizou-se um eletrogoniômetro flexível para mensurar o movimento da coluna e o programa 3D da Universidade de Michigan para estimar a compressão intradiscal em L5/S1 durante o manuseio. Foram avaliados os padrões de movimento normalizados e o coeficiente de variação foi aplicado para quantificar a variabilidade deste movimento. O teste t de student foi aplicado na determinação das diferenças para as variáveis em estudo. Os resultados apontam para uma grande variabilidade de posturas adotadas. Foram encontradas menores amplitudes de flexão, mas maiores amplitudes de extensão da coluna quando as cargas eram depositadas, respectivamente, em superfícies baixas e altas para indivíduos experientes. Sujeitos experientes apresentaram menores valores de compressão intradiscal durante a deposição da caixa e a atividade de abaixamento com 15kg foi caracterizada por maior sobrecarga intradiscal. O Estudo IV teve como objetivos comparar as estratégias de manuseio realizadas por sujeitos experientes e inexperientes com relação ao posicionamento dos pés e tronco durante atividade de abaixamento e de inclinação da carga no levantamento e abaixamento. Foram selecionados 10 trabalhadores experientes e 10 sujeitos sem experiência profissional com o manuseio de cargas. O manuseio realizado entre diferentes alturas foi filmado. Por meio de um programa de edição, as imagens referentes ao instante de 50% da tarefa foram selecionadas e utilizadas para classificar as posturas e mensurar a inclinação da caixa. Utilizou-se uma ANOVA com 3 fatores para avaliar a inclinação da carga com relação à experiência, carga manuseada e tipo de manuseio (levantamento e abaixamento). Os resultados indicaram que sujeitos com experiência profissional do manuseio adotaram estratégias caracterizadas pela maior inclinação da caixa e adoção de posturas mais equilibradas do tronco, com afastamento dos pés. A experiência profissional parece determinar a adoção de estratégias de movimento diferentes do grupo inexperiente, em resposta às condições da atividade. Entretanto, novos estudos são sugeridos com o intuito de determinar se tais estratégias foram protetoras ou de risco. Ainda, o conjunto de resultados apresentados na dissertação levanta a hipótese de que a flexibilidade dos isquiotibiais seja um fator de risco para o aumento de sobrecarga na coluna, durante a realização do manuseio de materiais.
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Exposição biomecânica durante o manuseio de caixas em ambiente real e simulado com trabalhadores industriais

Nogueira, Helen Cristina 18 November 2016 (has links)
Submitted by Aelson Maciera (aelsoncm@terra.com.br) on 2017-04-24T17:31:20Z No. of bitstreams: 1 TeseHCN.pdf: 982841 bytes, checksum: bcab3da38d92906a3e65c80c31f92e51 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-25T14:19:24Z (GMT) No. of bitstreams: 1 TeseHCN.pdf: 982841 bytes, checksum: bcab3da38d92906a3e65c80c31f92e51 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-25T14:19:34Z (GMT) No. of bitstreams: 1 TeseHCN.pdf: 982841 bytes, checksum: bcab3da38d92906a3e65c80c31f92e51 (MD5) / Made available in DSpace on 2017-04-25T14:28:40Z (GMT). No. of bitstreams: 1 TeseHCN.pdf: 982841 bytes, checksum: bcab3da38d92906a3e65c80c31f92e51 (MD5) Previous issue date: 2016-11-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Bundesministerium für Bildung und Forschung (BMBF) / Musculoskeletal risks involving manual box handling can be minimized with the adoption of preventive approaches such as the inclusion of handles in boxes. However, the literature indicates the acquisition of motor skills over working time, can also be a protective factor in development of musculoskeletal disorders. Thus, the study 1 aimed to evaluate the physical load of the upper arms and upper back between 37 novice and 21 experienced subject during handling a new box design compared to commercial ones. The order of surfaces to handle (places to boxes depositions – floor and shoulder levels) and the type of box was randomized. In addition to direct measures (electrogoniometry, inclinometry and electromyography) subjective scales were used to assess the comfort and perceived effort. In general, both experienced and inexperienced subjects had lower biomechanics load handling non-commercial boxes compared to commercial ones. However, the inexperienced subjects demonstrated greater reductions in physical overload during the handling of non-commercial boxes, being more advantageous the recommendation of these boxes for this user profile. In the real work setting, handling boxes is highly rotating mainly in developing countries. Thus, interventions focus on boxes could help the workers, who may have different levels of experience with the job. However, the real work environment involves other tasks besides handling box, and tasks distribution over time could minimize the handling risks. In this way, the study 2 has been proposed to assess the physical exposure in real environment, where in addition to handling box workers perform other activities, aiming to identify the representative handling task in the total work exposure. The biomechanical exposure was assessed from muscular electrical activity of trapezius and upper limb movement recordings during a period of 4 hours to the work routine. The results showed that handling box task required the greater activation of the trapezius in relation to other activities, particularly in peak loads (percentiles 90 and 99 APDF - Amplitude Probability Distribution Function). Effect size calculations have identified the magnitude of the difference between the tasks is large, particularly in peak loads. In relation to the total job, handling box differed by greater amplitudes of upper back forward flexion and left arm elevation postures. Thus, the handling task requires interventions to decrease the physical load in a real work environment in order to promote occupational health, as identified in simulated environment by other studies. The conclusions of this thesis are related to the importance of considering the profile of workers' experience and the need to assessment work exposure involving all tasks performed, emphasizing the importance of studies involving workers in the real working environment. / Os riscos musculoesqueléticos do manuseio de caixas podem ser minimizados a partir da adoção de medidas preventivas, como a inserção de alças em caixas. No entanto, a literatura aponta que a aquisição de habilidades motoras, ao longo do tempo de trabalho, também pode ser um fator protetor no desencadeamento de lesões musculoesqueléticas. Dessa forma, o Estudo 1 teve como objetivo avaliar a carga física dos membros superiores e do tronco superior imposta à 37 sujeitos inexperientes e 21 experientes durante o manuseio de um novo design de caixa, comparado às caixas comerciais. A ordem do ajuste das superfícies onde as caixas foram depositadas (chão e ombro) e da utilização das caixas foi randomizada. Além de medidas diretas (eletrogoniometria, inclinometria e eletromiografia) foram utilizadas escalas para avaliação da agradabilidade e do esforço percebido. Em linhas gerais, tanto os sujeitos experientes como os não experientes apresentaram menor carga biomecânica durante o manuseio das caixas não comerciais comparadas às comerciais. No entanto, os inexperientes demonstraram maiores reduções da sobrecarga física durante o manuseio das caixas não comerciais, sendo mais vantajosa a recomendação dessas caixas para esse perfil de usuário. O contexto real de trabalho, o manuseio de caixas nos países em desenvolvimento é altamente rotativo. Dessa forma, intervenções na caixa poderiam favorecer os trabalhadores, que podem ter diferentes níveis de experiência com o trabalho. No entanto, o ambiente real de trabalho envolve outras tarefas além do manuseio de caixas, e a forma como as tarefas são distribuídas ao longo do tempo poderiam minimizar os riscos do manuseio. Dessa forma, o estudo 2 foi proposto para avaliar a exposição física em ambiente real, onde além do manuseio de caixas os trabalhadores realizam outras atividades, a fim de identificar a representatividade do manuseio na exposição total do trabalho. A exposição foi avaliada a partir do registro da atividade elétrica muscular do trapézio e dos movimentos do membro superior durante um período de 4h da jornada de trabalho. Os resultados demonstraram que o manuseio de caixas exigiu a maior ativação do trapézio em relação às demais atividades realizadas, particularmente nas cargas de pico (percentis 90 e 99 da APDF – Amplitude Probability Distribution Function). Cálculos do tamanho do efeito identificaram que a magnitude da diferença entre as tarefas é grande, principalmente nas cargas de pico. Já em relação ao trabalho total, o manuseio de caixas se diferiu pelas maiores amplitudes da postura de flexão anterior da coluna superior e de elevação do membro superior esquerdo. Dessa forma, o manuseio de caixas requer intervenções para diminuição da sobrecarga física em ambiente real de trabalho, a fim de promover saúde ocupacional, como identificado em ambiente simulado por outros estudos. As conclusões desta tese são referentes à importância de se considerar o perfil de tempo de experiência dos trabalhadores, bem como a necessidade de avaliações da exposição do trabalho envolvendo todas as tarefas realizadas, enfatizando a importância de estudos realizados com trabalhadores e no ambiente real de trabalho. / FAPESP: 2013/04839-5 / FAPESP: 2015/12493-7 / CNPq: 162324/2012-0
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A utilização dos conceitos de manufatura enxuta e da teoria das restrições no abastecimento de uma linha de montagem / Using lean manufacturing and theory of constraints concepts on an assembly line supply

Puerta, Marcus Vinicius [UNESP] 24 June 2016 (has links)
Submitted by MARCUS VINICIUS PUERTA null (mvpuerta@gmail.com) on 2016-08-22T19:55:29Z No. of bitstreams: 1 Dissertação MVP Final.pdf: 3273798 bytes, checksum: b791361123375f0b442593d8b7acae86 (MD5) / Rejected by Ana Paula Grisoto (grisotoana@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão com o arquivo correto. Agradecemos a compreensão. on 2016-08-23T12:44:16Z (GMT) / Submitted by MARCUS VINICIUS PUERTA (mvpuerta@gmail.com) on 2016-08-23T15:19:31Z No. of bitstreams: 1 Dissertação MVP Final.pdf: 3359235 bytes, checksum: 885367a13dfa3a719a6d5d176985a236 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-24T17:00:02Z (GMT) No. of bitstreams: 1 puerta_mv_me_guara.pdf: 3359235 bytes, checksum: 885367a13dfa3a719a6d5d176985a236 (MD5) / Made available in DSpace on 2016-08-24T17:00:02Z (GMT). No. of bitstreams: 1 puerta_mv_me_guara.pdf: 3359235 bytes, checksum: 885367a13dfa3a719a6d5d176985a236 (MD5) Previous issue date: 2016-06-24 / O grande número de competidores globais existentes no mercado tem levado as indústrias da cadeia automotiva a buscarem incessantemente melhorias na gestão operacional, e nesse sentido esse trabalho apresenta uma proposta de integração das técnicas e abordagens da Manufatura Enxuta e da Teoria das Restrições, através de uma aplicação prática, visando a melhoria da sistemática de abastecimento de componentes para utilização em células de solda pertencentes a uma linha de montagem de chassis. Em uma primeira etapa foram apresentados os conceitos e as possibilidades de integração de ambas as teorias e, a partir de um diagnóstico inicial do sistema de abastecimento, foram propostas alterações, de maneira evolutiva, em que melhorias baseadas na Manufatura Enxuta eram implementadas a cada rodada de experimento, culminando com a implementação de melhorias baseadas na Teoria das Restrições, integrando ambos os conceitos. O resultado final obtido corrobora a eficiência da integração das duas abordagens para a melhoria de processos, as quais contribuíram para uma diminuição dos tempos de ciclo de abastecimento na ordem de 89% para a célula alvo estudada, sendo superior ao resultado obtido utilizando-se apenas uma das técnicas, sem que houvesse necessidade de investimentos e/ou despesas significativas. / The large number of global players in the market has led the automotive industry chain to incessantly seek improvements in operations management to increase their results and, based on this fact, this paper presents a proposal for integrating the techniques and approaches of Lean Manufacturing and Theory of Constraints through an action research application, aiming at improving the material supply system of welding cells from a chassis frame assembly line. In the first stage were presented the concepts and possibilities of integration of both theories and, from an initial diagnosis of the supply system, changes were proposed in an evolutionary way, in which improvements based on Lean Manufacturing were implemented on each experiment round, culminating in the implementation of improvements based on the Theory of Constraints, integrating both concepts. The final result confirms the efficiency of the integration of these two approaches as a way to improve processes, which contributed to an 89% decrease of the supply cycle times of the studied target cell. This result is better than the result obtained using only one of the techniques, without the need for investments and / or significant expenses.
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Movimentação manual de cargas e analise ergonomica do trabalho em unidades de beneficiamento de tomate de mesa / Manual material handling and ergonomics work analysis in fresh tomatoes packing houses

Ribeiro, Ivan Augusto Vall 26 February 2007 (has links)
Orientadores: Mauro Jose Andrade Tereso, Roberto Funes Abrahão / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-09T16:53:25Z (GMT). No. of bitstreams: 1 Ribeiro_IvanAugustoVall_M.pdf: 11470420 bytes, checksum: 7b4d66edae261245bb8810ee6aa0e792 (MD5) Previous issue date: 2007 / Resumo: A Tomaticultura constitui-se num dos maiores mercados agrícolas brasileiros, gerando mais de duzentos mil empregos diretos. Atualmente a exigência por produtos seguros se fortalece num ritmo muito acelerado, fazendo com que o beneficiamento pós-colheita dos produtos agrícolas se constitua numa atividade em grande expansão no Brasil. A Movimentação Manual de Cargas (MMC) nas unidades de beneficiamento de tomates (UB) é a atividade laboral mais freqüênte nas etapas do processo de beneficiamento e a que mais expõe os trabalhadores a riscos de lesão do sistema osteomuscular. O objetivo geral desse estudo foi analisar as tarefas de MMC das Unidades de Benrficiamento de Tomate de Mesa, visando contribuir para a prevenção das ocorrências de distúrbios osteomusculares nos trabalhadores. Para a realização do estudo, foram escolhidas seis Unidades de Beneficiamento, todas localizadas no estado de São Paulo. A compreensão do funcionamento geral das UB, foi possível a partir da aplicação do método da Análise Ergonômica do Trabalho (AET). Através de ferramentas que compõem o método da AET, como as observações sistemáticas, que possibilitaram o conhecimento do fluxo de produção, e as verbalizações dos trabalhadores, foi possível a identificação das etapas do processo de beneficiamento em que a MMC se apresentava com maior predominância. Para avaliar o risco de lesão do sistema osteomuscular dos trabalhadores nas etapas selecionadas dentro do processo de beneficiamento onde a MMC se apresentava de forma predominante, foram aplicados os métodos da equação National Institute for Occupational Safety and Health (NIOSH), que é um método de análise quantitativa e que determina o Limite de Peso Recomendado (LPR) para cada tarefa e o método do Diagrama das Áreas Dolorosas que é um método subjetivo em que os trabalhadores através de um questionário apontam para as áreas do corpo que apresentam desconforto. Em todas as etapas do processo de beneficiamento estudadas, o peso real da carga movimentada manualmente superou o limite de peso recomendado (LPR) pelo NIOSH. O Diagrama de Áreas Dolorosas identificou extremo desconforto na área posterior do tronco, ombros, braços e antebraços, corroborando os resultados obtidos pela equação do NIOSH / Abstract: Tomato cropping is one of the biggest Brazilian agriculture markets, that generates more than 200,000 direct jobs. Nowadays the demand for safe products increases in a very accelerated rhythm, making the post harvest beneficiary process of the agriculture products an activity with a great expansion in Brazil. The manual material handling (MMH) in the fresh tomatoes packing houses is the most frequent labor activity in the phases of beneficiary process and the one of major risk of bone-muscle system lesion to the workers. The main goal of this work was to analyze the MMH tasks in six table tomato packing house in order to contribute to the prevention of the bone-muscle disturb occurrences in them. To accomplish this six packing houses located in São Paulo state were chosen. The comprehension of the packing house general functionalities was accomplished from the application of Work Ergonomic Analyses (WEA) method. Using WEA method tools, as the systematic observations, made it possible the identification of beneficiary process phases in which the MLM was predominant. In order to evaluate the risk of bone-muscle system lesion of the workers in the selected phases of the beneficiary process where MMH was predominant, two methods were applied: the first one was the Equation Method of the National Institute for Occupational Safety and Health (NIOSH), which is a quantitative analysis method that determines the Recommended Weight Limit (RWL) for each task. The second one was the Painful Area Diagram method, which is a subjective method where the workers indicates, through a questionnaire, the body areas which present discomfort. In all studied phases of the beneficiary process, the actual load weight manually moved overcome the NIOSH recommended weight limit (RWL). The painful area diagram identified extremely discomfort in the posterior area of the trunk, shoulders, arms and forearms, reaffirming the results obtained by the NIOSH equation / Mestrado / Planejamento e Desenvolvimento Rural Sustentável / Mestre em Engenharia Agrícola

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