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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.
21

Estudos funcionais da proteína reguladora humana Ki-1/57 e seus parceiros de interação / Functional studies of the human regulatory protein Ki-1/57 and its interaction partners

Gonçalves, Kaliandra de Almeida, 1984- 07 December 2011 (has links)
Orientador: Jörg Kobarg / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-18T16:47:23Z (GMT). No. of bitstreams: 1 Goncalves_KaliandradeAlmeida_D.pdf: 14162647 bytes, checksum: a062a24283fc9889ec54663e0b624c2f (MD5) Previous issue date: 2011 / Resumo: A proteína Ki-1/57 foi descoberta através da reação cruzada do anticorpo monoclonal Ki-1 em células do linfoma de Hodgkin. Estudos anteriores demonstraram que Ki-1/57 interage com a proteína RACK-1, sofre fosforilação por PKCs e metilação por PRMT1, uma arginino metiltransferase que modula diversas proteínas ligantes ao RNA. Estudos mostraram que Ki- 1/57 é capaz de controlar o splicing do pré-mRNA do gene viral E1A. Análises por SAXS, gel filtração analítica e ultracentrifugação analítica indicaram uma estrutura bastante alongada e flexível para a construção C-terminal 6xhis-(122-413)Ki-1/57. Ensaios de proteólise limitada também mostraram uma baixa composição de núcleos hidrofóbicos estáveis e compactos, sugerindo que a proteína é intrinsecamente desordenada, o que pode explicar o elevado número de diferentes proteínas parceiras que ela é capaz de interagir. Neste trabalho foi identificada a interação de Ki-1/57 com proteínas da Família do X frágil, e sua localização no Perfil Ribossomal, além de ser capaz de ativar a tradução quando conectada ao gene repórter da Luciferase. Outra observação importante é que Ki-1/57 é sumoilada in vitro e in vivo, sendo as lisinas alvos desta sumoilação identificadas, e a proteína não sumoilada é incapaz de atuar no splicing do pré-mRNA do gene viral E1A. Mais experimentos foram feitos no sentido de caracterizar a interação RACK-Ki-1/57. A interação entre as duas proteínas é forte, possuindo uma constante de dissociação de 0,7 ?M, seguindo uma estequiometria de 1:1 observada em experimentos de sedimentação em equilíbrio. Experimentos de ultracentrifugação analítica mostraram que a proteína RACK1 tem propriedades hidrodinâmicas similares ao seu modelo predito por homologia, e que em solução ela é encontrada em sua forma monomérica, possuindo uma leve tendência a agregação. A superexpressão de Ki-1/57 e CGI-55 provocou a alteração de 413 e 217 genes respectivamente, que em sua grande maioria foram regulados negativamente. A maioria dos genes, que foram inibidos pela superexpressão de Ki-1/57, estão envolvidos na proliferação celular, muitos sendo expressos em diferentes tumores. Os dados obtidos no teste do MTS confirmam que houve uma diminuição na proliferação celular em células superexpressando as proteínas Ki-1/57 e CGI-55. Com base nos resultados obtidos neste trabalho, novas funções da proteína Ki-1/57 foram descritas, tais como: a influência de Ki-1/57 na proliferação celular, na tradução proteica e o papel importante que a modificação pós traducional, como a sumoilação, representa para que a proteína Ki-1/57 desempenhe sua função / Abstract: The protein Ki-1/57 was discovered through cross reactivity of the monoclonal antibody Ki-1 in cells of Hodgkin lymphoma. Previously studies demonstrated that Ki-1/57 interacts with RACK-1 protein, undergoes phosphorylation by PKCs and methylation by PRMT1, an arginine methyltransferase that modulates several RNA binding proteins. Studies have shown that Ki- 1/57 is able to control the pre-mRNA splicing of the viral E1A gene. SAXS analysis, analytical gel filtration and analytical ultracentrifugation indicate a rather elongated and flexible structure to build C-terminal 6xhis-(122-413) Ki-1/57. Limited proteolysis assays also showed a low composition of stable and compact hydrophobic cores, suggesting that the protein is intrinsically unstructured, it could explain the wide array of protein partners with which it is able to interact. In this work we identified the interaction of Ki-1/57 proteins with Family fragile X, and its location on Ribosomal profile, besides being able to increase the translation when tethered to the reporter gene Luciferase. Another important observation is that Ki-1/57 is sumoylated in vitro and in vivo, the targets of this lysine sumoylated were identified, and the not somoylated protein is unable to act in the pre-mRNA splicing of E1A. More experiments were made to characterize the interaction of RACK1 with Ki-1/57. The interaction between the two proteins is strong, possessing a dissociation constant of 0.7 ?M and follows the stoichiometry of 1:1 as observed by sedimentation equilibrium experiments. Analytical ultracentrifugation experiments showed that human RACK1 has similar hydrodynamic properties to that predicted to homology model, and that in solution it is found in its monomeric form, with a slight tendency to aggregation. Overexpression of Ki-1/57 and CGI-55 caused changes in 413 and 217 genes respectively, which were mostly negative regulated. Most genes that were inhibited by overexpression of Ki-1/57 are involved in cell proliferation, and expressed in different types tumors. The MTS data obtained confirm a decrease in cell proliferation through overexpressing of Ki-1/57 and CGI-55 protein. Based on the results of this study new functions for Ki-1/57 protein have been described such as: the influence of Ki- 1/57 in cell proliferation, in protein translation and the important role that the post translational modification, such as sumoylation, represents so that the protein Ki-1/57 performs its function / Doutorado / Bioquimica / Doutor em Biologia Funcional e Molecular
22

Automatic Billiards Table / Automatisk Biljard

Zhou, Fei, Cai, Hantao, Zhang, Ruoyu January 2014 (has links)
With the development of the society, people are more willing to focus on their leisure activities. A growing number of new equipment are created nowadays. For example, automatic mahjong machine in China. Inspired by the automatic mahjong machine, we propose to add some devices on the billiard table to achieve sorting balls automatically. It includes recognition system, ball-separating system, and sorting system. We use Autodesk Inventor 2012 to model the billiards table. Some complex calculations and nonlinear analysis are completed by Matlab. Through our method, we can achieve the purpose of sorting balls automatically. / Med utvecklingen av samhället, människor är mer villiga att fokusera på sina fritidsaktiviteter. Ett växande antal av ny utrustning skapas nuförtiden. Till exempel, automatisk mahjong maskin i Kina. Inspirerad av den automatiska mahjong maskin, föreslår vi att lägga till några enheter på biljardbordet för att uppnå sorterings bollar automatiskt. Den innehåller igenkänningssystem, boll-separerar systemet, och sorteringssystem. Vi använder Autodesk Inventor 2012 för att modellera tabellen biljard. Vissa komplexa beräkningar och olinjär analys är klara med Matlab. Genom vår metod kan vi uppnå syftet att sortera bollar automatiskt.
23

Utveckling av CBC Strap Cutter : Genom att möjliggöra en viss materialseparation tillsammans med en förenklad tömningsprocess

Blåbäck, Ludvig, Khalil, Gilbert January 2016 (has links)
Syfte – Under detta examensarbete har en vidareutveckling av Cyklop Teknik AB:s existerande produkt, CBC Strap Cutter, utförts. Varav det är en maskin som kapar upp emballageband för att minska hur mycket plats avfallet tar upp, speciellt under avfallstransport. Några problemområden hade uppenbarats efter dess introduktion. En av dessa var att tömningen var omständlig då flera onödiga moment behövde utföras innan tömningen kunde ske. Bland annat i form av att lyfta maskinen från avfallstunnan som också vanligtvis agerade som ställning. Sedan efterfrågades en materialsorteringsfunktion, i form av plast och ferromagnetiskt metall, från Cyklop Teknik AB:s håll. Metod – Utförandet av arbetet har fortgått genom att färdigställa en konceptstudie. Först sammanställdes en kravspecifikation [bilaga 1] och ett Gantt-schema [bilaga 3], de var för att ge ett riktmärke för vad som skulle göras och när. Sedan gick arbetet vidare med att göra konkurrensanalyser och förstudier. Det var för att observera hur konkurrenter och närliggande industrier hade löst vissa problemområden. Ytterligare etablerades det att ingen konkurrent hade en liknande produkt som kunde sortera ingående material. Därefter utfördes konceptgenerering i form av bland annat Brainstorming för att lösa de nämnda problemområdena. Vidare har de olika koncepten sållats ut genom direkt feedback samt en metod som kallas ”Concept scoring matrix”. Till sist återstod ett enda koncept som vidareutvecklades i CAD-miljö, specifikt i SolidWorks. Resultat – Det slutliga resultatet var ett resultat som hade delats upp i olika underkomponenter. Dessa var skärande maskin, separeringsmodul, ställning och avfallstunna. Den skärande maskinen var just den delen som kapade upp det ingående materialet och den behölls så snarlik till originalet som möjligt. Det var för att låta Cyklop Teknik AB:s maskinpark och processer vara så lik som det redan var. För separeringen utvecklades en modul som använde sig av en roterande magnettub. Anledningen till det var för att det skulle ge Cyklop Teknik AB möjligheten att sälja konceptet med eller utan sortering utan att något annat påverkades. Samtidigt skulle modulen kunna anpassas och säljas för andra områden där snabb sortering av nämnda material skulle behöva utföras. En ställning har också tagits fram för att förenkla tömningen som var en kritisk del av arbetet. Eftersom inga onödiga moment skulle uppstå i så fall. Samtidigt utformades ett koncept på en avfallstunna som kunde också den underlätta tömningen. Avfallstunnan utformades därför med både hjul och truckspår för att erbjuda stora möjligheter för användaren. En enskild tömningsprocess för enbart den utvecklades också för att möjliggöra tömning när den skulle vara upphöjd av en truck. Begräsningar – Detta projekt har endast tagit fram en prototyp i CAD-miljö som skulle kunna utvecklas vidare. Anledningen till det var den korta tidsramen för projektet. Sedan har inga simuleringar eller uträkningar utförts på konceptet för att verifiera och optimera konceptet på varje område. Likaså var det på grund av den korta tidsramen. Ingen kundstudie utfördes inte heller, utan istället fortgick arbetet med information som fåtts från Cyklop Teknik AB. / Purpose - In this thesis a further development of Cyklop Teknik AB's existing product, CBC Strap Cutter, has been developed. The product is a machine that cuts packaging tape to reduce the amount space the waste takes up, especially during waste transports. Some problem areas had been revealed after the market introduction of the product. One of these problems was that several unnecessary steps had to be performed before the waste bin could be emptied. One of these step was lifting the machine from the waste bin who also acted as a rack of sorts. A material sorting function, for plastics and ferromagnetic metals, was also requested by Cyklop Teknik AB. Method – The work has been performed by completing a concept study. First a requirement specification [appendix 1] and a Gantt chart [appendix 3] was developed to provide a benchmark for what should be done and when. The work that followed thereafter was a competitive analysis supplemented by a pre-study. The purpose of these studies was to observe how the competitors and related industries had solved these and related problems. Results from the studies that was performed made it clear that no competitor had a similar product that could sort the materials. Brainstorming was thereafter performed to develop new ideas as a help to solve the aforementioned problems and to generate new concepts. Furthermore, the most appropriate concepts was selected through direct feedback from Cyklop Teknik AB among others and a method called "Concept Scoring Matrix". Finally one concept remained and was further developed in a CAD environment, specifically in SolidWorks. Results - The final result was a concept that had been divided into different sub-components. These were cutting machine, separation module, rack and waste bin. The cutting machine was the part cut up the input material. This in turn was kept as close to the original machine as possible and only acquired minor adjustments. In doing so Cyklop Teknik AB's manufacturing processes could remain similar as they have been. A module was developed for the separation, it in turn was constructed with a spinning magnetic tube. The reason for this was that it would give the company possibility of selling the concept with or without the sorting module and its function. At the same time the module could be adapted and sold for other areas where fast sorting of said material would need to be performed. A rack has also been developed to simplify the vacating of the waste bin that was a critical part of the work. In doing so there would be no unnecessary moments that had to be performed. A waste bin was also designed with both wheels and forklift slots to facilitate emptying and offer great opportunities for the user. A single emptying process was developed and made it possible to empty the waste bin when it would be hoisted by a forklift. Restrictions - This project has only developed a prototype in CAD that in turn could be developed further. The reason for this was the short time frame that was allocated for the thesis. No simulations or computations were either performed to validate and optimize the concept in each area. Likewise, it was because of the short time frame. No customer study has been conducted, the work has instead been based on the information received from the Cyklop Teknik AB.
24

Utveckling av ett cykelskåp anpassat för stadsmiljö / Development of a bike box matching city environments

Öberg, Daniel January 2019 (has links)
Projektet började som en öppen fråga i samarbete med ett konsultföretag inom produktutveckling att utveckla en säkrare parkering för cyklar. Det utfördes därför en omfattande förstudie för att utvärdera cykelvärlden och se potentiella utvecklingsmöjligheter hos olika typer av cykelparkeringar. Blidsberg mekaniska är ett företag som tillverkar cykelparkeringar och andra sorts produkter för utemiljöer. De involverades i arbetet och ville utöka sitt sortiment med ett nytt cykelskåp. Designprocessen började med en bred marknadsundersökning för att analysera befintliga cykelparkeringar i en förstudie. Under förstudien samlades även behov in som sedan skapade en kravspecifikation. Det kreativa arbetet i att utveckla ett nytt cykelskåp tog hjälp av olika kreativitetsmetoder som genererade flertalet koncept som sedan jämfördes i en matris. Ett vinnande koncept framställdes och kunde konkurrera med en redan befintlig lösning. Resultatet blev en kombination av redan befintliga lösningar. Cykelskåpet tar inte upp mer plats än behövligt för att de flesta cyklar ska få plats. Skåpet är modulanpassat och kan därför placeras mer platseffektivt på olika platser. En ljusindikation på handtaget visar om skåpet är ledigt eller upptaget och öppnas med en tagg som skannas på en RFID-läsare. / The project began as an open question in collaboration with a consulting company in product development to develop a more secure parking for bicycles. Therefore, a comprehensive feasibility study was performed to evaluate the bicycle values and to see potential development opportunities for different types of bicycle parking. Blidsberg mekaniska is a company that manufactures bicycle parking and other types of outdoor environment products. They were involved in the work and wanted to expand their range with a new bike box. The designprocess started with a marketreasearch with the aim to analyze cycle parks in a pre-study. During the pre-study demands was researched and formed a requirement specification. The creative work in the development of a new cycle park was helped by many creative methods that generated many concepts that later was compared in a matrix. The final concept was able to compete with the existing solutions. The result was a combination of already existing solutions. The bicycle locker does not take up more space than is necessary for most bicycles to fit in. The bicycle locker is modularly adapted and can therefore be placed more space efficiently in different places. A light indication on the handle indicates whether the bicycle locker is free or occupied and opened with a tag that is scanned on a RFID-reader.
25

Comparativo de empenamento e microestrutural em cremalheiras de aço SAE 1045 temperadas por indução e por condução / Comparison of warpage and microstructure in SAE 1045 steel racks quenched by induction and by conduction

Amaral, Regis Fabiano do January 2016 (has links)
A microestrutura de uma peça temperada determina suas características mecânicas. Dessa forma, torna-se fundamental conhecer os parâmetros que influenciam na formação da estrutura do componente tratado com função dos tratamentos térmicos aplicados, permitindo obter melhorias de qualidade de uma peça frente a sua aplicação. Métodos distintos podem ser empregados para obtenção da camada de têmpera. Entretanto, esses métodos devem ser parametrizados adequadamente para garantir a qualidade do produto final. No trabalho em questão, aplicaram-se dois metódos distintos de têmpera: por indução e por condução para obtenção da camada martensítica, dureza e durabilidade requerida em cremalheiras de aço SAE 1045, utilizadas em mecanismo de direção automotiva. Fabricou-se um lote de peças, do qual metade das peças foram tratadas por indução e a outra por condução. Após a têmpera e após o revenido, foi avaliado o nível de empenamento, a dureza superficial, a microdureza, a microestrutura formada. A peças após o término do processo de fabricação, foram montadas no sistema caixa de direção, sendo realizados ensaios de durabilidade e impacto dos mesmos. Os tratamentos realizados demonstraram resultados de empenamento, dureza, microestrutura e ensaios de durabilidade e impacto no produto final, dentro das especificações. O processo de têmpera por condução levou a melhor micrestrutura, mais alta dureza e menores níveisde empenamento comparado com o processo de têmpera por indução. Mas, também constatou-se que é possível desenvolver melhorias no processo de indução para atingir-se resultados melhores. / The microstructure of a hardened part is determining its mechanical characteristiscs. Thus, the knowledge of pararameters influencing the heat treated part’s microstructure is of fundamental importance. This allows to obtain quality improvements for specific applications. Diferent methods can be used for the obtation of a hardened layer. However, in these methods the parameters have to be correctly set to reach the final product quality. In this work, two diferente techniques were applied, induction and conduction surface hardening to obtain a required martensitic layer depth, hardness and durability of SAE 1045 steel racks used in automotive driving systems. A batche of parts were manufactured, being half of the parts surface hardened by Induction and half by conduction. After hardening and after tempering, the warpage level, surface hardness, microhardness and microstructure were investigated. The parts were mounted in a steering gear system and then endurance tests and impact tests were carried out. The results of warpage levels, hardness, microstructure and endurance tests, as well as the impact tests were in the range of the specifications. The conduction hardening process leads to better microstructure, higher hardness and lower warpage levels compared to induction hardening. But it was found that the Induction hardening can be optimized to reach better results.
26

Improving the time frame reduction for reuse of roof rack components in cars using Case-based reasoning

Harish Acharya, Maniyoor, Sudsawat, Suppatarachai January 2012 (has links)
Now a days where technological advancements are growing at a rapid pace, it has become a common norm for all the manufacturing companies to be abreast with these advancements for being competitive in market. This thesis deals with development of one such common norm for one of the products (Roof rack component) for company Thule. The main aim of the thesis is to curtail the products lead time to market and this was achieved by using an artificial intelligence technique i.e., Case-based reasoning (CBR). Roof rack component which is mounted on car roof is mainly constituted by two parts foot pad and bracket, this thesis main interest was concerned with only brackets and its geometry. This thesis is based on contemplating the already implemented concepts in this context, designer requirements and exploring better solutions. The methods of implementation adopted here was using CBR concept which is based on indexing , retrieve, adapt, review, retain and employing these concepts in form of an algorithm. The concept for developing the algorithm was based on Iterative closest point (ICP) approach which emphasise on assigning lower weight to pairs with greater point to point distance. The results portrayed are with respect to geometry and also with respect to application interface developed, which both together provides us a better solution.
27

The Influence of Under Sleeper Pads on Railway Track Dynamics

Witt, Stephen January 2008 (has links)
In this work the influence of Under Sleeper Pads on the dynamic forces on a railway track is investigated. A special interest is devoted to the effect of using Under Sleeper Pads in a railway track with changing vertical stiffness. The contact force between wheel and rail and the ballast contact forces are examined. For the investigation a finite element model with the length of thirty sleepers is created and calculations are performed with the software LS-DYNA. Three different cases of varying vertical track stiffness are studied: the transition from an embankment to a bridge, a randomly varying track stiffness along the railway track and hanging sleepers.
28

The Influence of Under Sleeper Pads on Railway Track Dynamics

Witt, Stephen January 2008 (has links)
<p>In this work the influence of Under Sleeper Pads on the dynamic forces on a railway track is investigated. A special interest is devoted to the effect of using Under Sleeper Pads in a railway track with changing vertical stiffness. The contact force between wheel and rail and the ballast contact forces are examined. For the investigation a finite element model with the length of thirty sleepers is created and calculations are performed with the software LS-DYNA. Three different cases of varying vertical track stiffness are studied: the transition from an embankment to a bridge, a randomly varying track stiffness along the railway track and hanging sleepers.</p>
29

Robot Racking : A Racking Solution for Autonomous Production

Envall, Zakarias January 2018 (has links)
As an engineering student, the most natural way of summarizing this thesis project is by relating it to a mathematical equation. The solution to this equation is given, and it is in the form of a racking concept that enables the use of robots. The other side of the equation is however a bit more complex. This side contains several undefined variables, which can only be solved by delving into various theoretical fields and exploring unchartered depths of the creative space.The project’s main objective is to design a concept rack for Gestamp HardTech in Luleå, Sweden, for storage and in-house transport of the beams which are produced at the HardTech facility. The rack is meant to be loaded both into and out of by robots and should suit an as wide array of beams as possible. To determine the possibilities and limitations of the rack’s robot-user, several automation aspects are researched, centered on industrial robots and machine vision. The beams which are produced at the Gestamp HardTech Luleå production plant today are analyzed, whereby twelve of them are ultimately chosen for the rack’s design to be focused on. What follows this is a creative process consisting of a creative idea-generating phase, an evaluative phase focused on implementation of the ideas, and a refinement phase where the rack concept is finalized. The process includes various methods of idea generating, a great deal of sketching, physical testing of the concepts, and finally CAD-modeling. The result, named 4.0-Rack, is in the form of a modular rack-concept which balances the aspects of flexibility, by suiting ten of the reviewed beams, with a high packing-grade, providing a mean packing-grade of 83% in relation to the way the beams are currently packed.
30

Comparativo de empenamento e microestrutural em cremalheiras de aço SAE 1045 temperadas por indução e por condução / Comparison of warpage and microstructure in SAE 1045 steel racks quenched by induction and by conduction

Amaral, Regis Fabiano do January 2016 (has links)
A microestrutura de uma peça temperada determina suas características mecânicas. Dessa forma, torna-se fundamental conhecer os parâmetros que influenciam na formação da estrutura do componente tratado com função dos tratamentos térmicos aplicados, permitindo obter melhorias de qualidade de uma peça frente a sua aplicação. Métodos distintos podem ser empregados para obtenção da camada de têmpera. Entretanto, esses métodos devem ser parametrizados adequadamente para garantir a qualidade do produto final. No trabalho em questão, aplicaram-se dois metódos distintos de têmpera: por indução e por condução para obtenção da camada martensítica, dureza e durabilidade requerida em cremalheiras de aço SAE 1045, utilizadas em mecanismo de direção automotiva. Fabricou-se um lote de peças, do qual metade das peças foram tratadas por indução e a outra por condução. Após a têmpera e após o revenido, foi avaliado o nível de empenamento, a dureza superficial, a microdureza, a microestrutura formada. A peças após o término do processo de fabricação, foram montadas no sistema caixa de direção, sendo realizados ensaios de durabilidade e impacto dos mesmos. Os tratamentos realizados demonstraram resultados de empenamento, dureza, microestrutura e ensaios de durabilidade e impacto no produto final, dentro das especificações. O processo de têmpera por condução levou a melhor micrestrutura, mais alta dureza e menores níveisde empenamento comparado com o processo de têmpera por indução. Mas, também constatou-se que é possível desenvolver melhorias no processo de indução para atingir-se resultados melhores. / The microstructure of a hardened part is determining its mechanical characteristiscs. Thus, the knowledge of pararameters influencing the heat treated part’s microstructure is of fundamental importance. This allows to obtain quality improvements for specific applications. Diferent methods can be used for the obtation of a hardened layer. However, in these methods the parameters have to be correctly set to reach the final product quality. In this work, two diferente techniques were applied, induction and conduction surface hardening to obtain a required martensitic layer depth, hardness and durability of SAE 1045 steel racks used in automotive driving systems. A batche of parts were manufactured, being half of the parts surface hardened by Induction and half by conduction. After hardening and after tempering, the warpage level, surface hardness, microhardness and microstructure were investigated. The parts were mounted in a steering gear system and then endurance tests and impact tests were carried out. The results of warpage levels, hardness, microstructure and endurance tests, as well as the impact tests were in the range of the specifications. The conduction hardening process leads to better microstructure, higher hardness and lower warpage levels compared to induction hardening. But it was found that the Induction hardening can be optimized to reach better results.

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