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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Rotorsaksanalyser av testriggar : En studie av vad som krävs av Scanias forsknings- och utvecklingsavdelning för att rotorsaksanalyser ska fungera på bästa sätt / Root Cause Analysis of Test Beds : A study of what is needed from Scania's Research- and Development department to make Root Cause Analysis work in the best possible way

Lidström, Jonatan January 2015 (has links)
När Scanias maskiner som ska testa nya lastbilskomponenter eller hela lastbilar, så kallade testriggar, inte fungerar som de ska så fanns det i dagsläget en uppfattning att problemen i vissa fall dels var återkommande och dels var svåranalyserade. På grund av detta ville Scania Tekniskt Centrum (STC) införa rotorsaksanalyser av när testriggar inte fungerade som de skulle. Denna studie har undersökt vad som i dagsläget behövde förändras och vad som möjliggjorde att rotorsaksanalyser av fallerande hos testriggarna skulle fungera så bra som möjligt. En nulägesanalys gjordes. Resultaten av denna visade på att fyra roller fanns som var involverade i att åtgärda fel hos testriggarna, nämligen de som äger riggarna, de som arbetar med underhåll av riggarna, de som utvecklar riggarna och de som är ansvariga för arbetsmiljön och säkerheten hos riggarna. En process map skapades för att visa hur dessa roller i dagsläget samverkade för att bygga testriggar och åtgärda fel hos dem. Resultaten av nulägesanalysen visade på att fyra övergripande faktorer påverkade huruvida rotorsaksanalyser skulle kunna genomföras. Den första var att ha ett väldefinierat standardförfarande att följa. Den andra var att det fanns en kultur som tillät att utföra rotorsaksanalyser. Den tredje var att bakgrundskunskap kring ett fel skulle finnas tillgänglig. Den fjärde var att kunna sammansätta grupper av olika typer av roller som skulle kunna samarbeta. Dessa fyra faktorer var de som utgicks ifrån för att redovisa saker som fungerade väl och saker som krävde förändring för att rotorsaksanalyser skulle fungera på bästa sätt. Utöver detta gavs förslag på förändringar som skulle åtgärda saker som förhindrade rotorsaksanalyser.
12

Desenvolvimento da linhagem celular LEY79SF para produção de adenovírus livre de partículas competentes de replicação / Development LEY79SF line for production of RCA-free Ad

Duarte, Patrícia 05 October 2009 (has links)
A presença de Ad com competência para replicar (RCA, replication-competent adenovirus) nas preparações é um dos maiores problemas para a produção de Ad em larga escala. RCAs são gerados pela recombinação entre seqüência do vetor e seqüência homóloga do gene E1 presente nas células helper. Objetivo: desenvolver uma nova linhagem auxiliar para produção de Ad livre de RCA - LEY79 - derivada da linhagem de retinoblastoma humano Y79, tratando-se da primeira linhagem empacotadora de adenovírus com inativação mutacional da proteína supressora de tumor pRb, que crescem em suspensão. Células Y79 foram infectadas com o retrovírus pCLDE1A/E1BSN, selecionadas com G418. A eficiência de produção de AdeGFP na linhagem LEY79 foi testada e comparada com a HEK293A. Células Y79 foram adaptadas em meio livre de soro. Esperamos com a linhagem LEY79SF inovar no campo de processos para a produção de Ad recombinante. / The presence of Ad with the ability to replicate (RCA, replication-competent adenovirus) in preparations is a major problem in the large-scale production of Ad. RCAs are generated by recombination between the vector sequence and sequence of the homologous gene in E1 helper cells. Objective: To develop a new helper cell line for the production of RCA-free Ad., called LEY79, derived from the Y79 of human retinoblastoma line, the first line Packer adenovirus with mutational inactivation of the tumor suppressor protein pRb, which are adapted to grow in suspension. Y79 cells were infected with the retrovirus pCLDE1A/E1BSN, selected with G418. The efficiency of production of AdeGFP in the LEY79 was tested and compared with the HEK293A. Y79 cells were adapted to grow in serum-free medium. We hope that use of the the LEY79SF cell line will promote innovation in the processing and production of recombinant Ad.
13

Tillämpa Root Cause Analysis på återkommande problem med administrativa symptom : En explorativ studie av materialdifferenser inom Volvo Car Body Components

Wedelin, Erik, Carlström, Philip January 2015 (has links)
Root Cause Analysis (RCA) är en metodik som kan användas vid problemlösning för att gå till botten av en problemsituation och lösa ut de grundläggande orsakerna bakom problematiken. Problemet med RCA är att denna metod har främst undersökts och använts i sammanhang då ett problem med fysisk händelse, ett praktiskt symptom, har inträffat. En enligt studenterna förbisedd del av denna forskning berör problem där symptomet inte kan kopplas till en fysisk händelse – ett administrativt symptom. Syftet med denna studie är att tillämpa RCA på ett problem med administrativt symptom för att sedan ställa detta resultat i relation till andra studier med praktiska respektive administrativa symptom. Därefter gör studenterna bedömningen huruvida RCA är en lämplig metodik vid tillämpningen av ett administrativt symptom eller inte.   Denna studie har genomförts på Volvo Cars Body Components (VCBC) i Olofström där det undersökta problemet med administrativt symptom har varit VCBCs materialdifferenser på produktionsmaterialet plåt. Utifrån denna studie framkom sex rotorsaker bakom VCBCs problematik, vilka alla oberoende av varandra gav upphov till problematiken. Denna trend kunde uppvisas i annan studie med administrativt symptom, men kunde inte uppvisas i någon studie då ett praktiskt symptom studerats. En slutsats av denna studie visar på att skillnaden mellan ett problem med ett praktiskt respektive administrativt symptom ligger i själva ursprunget till den grundläggande rotorsaken. I fall med praktiska symptom kan denna direkt hänvisas till en mänsklig faktor som ursprung till problematiken, en trend som inte framgår i de fall då ett administrativt symptom undersökts. Det är också studenternas slutsats att RCA är en lämplig metodik att använda vid problem med administrativa symptom. / Root Cause Analysis (RCA) is a method that can be used in problem solving to get to the bottom of a problem situation and solving the root causes behind the problems. The problem of RCA is that this method has mainly been studied and used in contexts where a problem with the physical event, a practical symptom occurred. According to the students, an overlooked part of this research addresses problems where the symptom cannot be linked to a natural event – an administrative symptom. The purpose of this study is to apply RCA to a problem with an administrative symptom in order to then set the result in relation to other studies with practical and administrative symptoms. Thereafter the students will do the assessment whether RCA is a suitable methodology to apply on an administrative symptom or not.   This study was conducted at Volvo Cars Body Components (VCBC) in Olofström where the investigated problem with an administrative symptom has been VCBCs material differences in the production material sheet. Based on this study six root causes were revealed to be behind VCBCs problems, where all, independent of each other, gave rise to problem. This trend could be presented in another study with administrative symptom, but could not be produced in any study where a practical symptoms was studied. One conclusion of this study show that the difference between a problem with a practical respectively administrative symptom lies in the very origin of the fundamental root cause. In cases of practical symptoms, this may actually refer to a human factor as the origin of the problem, a trend which is not clear in cases where an administrative symptom is investigated. It is also the student's conclusion that RCA is an appropriate methodology to use in case of problems with the administrative symptoms
14

Desenvolvimento da linhagem celular LEY79SF para produção de adenovírus livre de partículas competentes de replicação / Development LEY79SF line for production of RCA-free Ad

Patrícia Duarte 05 October 2009 (has links)
A presença de Ad com competência para replicar (RCA, replication-competent adenovirus) nas preparações é um dos maiores problemas para a produção de Ad em larga escala. RCAs são gerados pela recombinação entre seqüência do vetor e seqüência homóloga do gene E1 presente nas células helper. Objetivo: desenvolver uma nova linhagem auxiliar para produção de Ad livre de RCA - LEY79 - derivada da linhagem de retinoblastoma humano Y79, tratando-se da primeira linhagem empacotadora de adenovírus com inativação mutacional da proteína supressora de tumor pRb, que crescem em suspensão. Células Y79 foram infectadas com o retrovírus pCLDE1A/E1BSN, selecionadas com G418. A eficiência de produção de AdeGFP na linhagem LEY79 foi testada e comparada com a HEK293A. Células Y79 foram adaptadas em meio livre de soro. Esperamos com a linhagem LEY79SF inovar no campo de processos para a produção de Ad recombinante. / The presence of Ad with the ability to replicate (RCA, replication-competent adenovirus) in preparations is a major problem in the large-scale production of Ad. RCAs are generated by recombination between the vector sequence and sequence of the homologous gene in E1 helper cells. Objective: To develop a new helper cell line for the production of RCA-free Ad., called LEY79, derived from the Y79 of human retinoblastoma line, the first line Packer adenovirus with mutational inactivation of the tumor suppressor protein pRb, which are adapted to grow in suspension. Y79 cells were infected with the retrovirus pCLDE1A/E1BSN, selected with G418. The efficiency of production of AdeGFP in the LEY79 was tested and compared with the HEK293A. Y79 cells were adapted to grow in serum-free medium. We hope that use of the the LEY79SF cell line will promote innovation in the processing and production of recombinant Ad.
15

The influence of percentage replacement on the aggregate and concrete properties from commercially produced coarse recycled concrete aggregate

Immelman, Derick Wade 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The aim of this research is to investigate the potential use of coarse recycled concrete aggregate (RCA) as a material in structural concrete. The lack of knowledge and specifications in South Africa are the main reasons for this research of RCA. By increasing the database of research of RCA in South Africa the possibility of specifications for this alternative building material can be initiated. The implications of such specifications would lead to RCA acceptance in concrete design and therefore reducing the amount of construction and demolition (C&D) waste accumulating at landfill sites and decreasing the extraction of depleting natural aggregates. The objectives that are achieved through this research project are firstly, what is the percentage replacement of RCA to a concrete blend that will produce a material that achieves similar or better results than a concrete blend containing natural aggregates. Secondly, what aggregate properties and limits should be defined in the specification of RCA for it to be accepted as a material in concrete mixtures. The objectives were assessed through examining the geometrical, physical and chemical properties of the aggregate as a material and the fresh and hardened concrete properties of concrete which contains RCA as a constituent. RCA which was processed by a commercial recycling facility which produces concrete masonry units was collected at three different instances. This material was reprocessed in the laboratory to control the grading and amount of fine material not guaranteed by the recycling process. The RCA is then combined with natural aggregate (NA) at the replacement percentages: 0, 15, 30, 50 and 100% which is then used to examine the aggregate properties. It was determined that the physical properties of RCA were dependent on the geometrical properties, while taking into consideration that the geometrical properties are dependent on the source and method of recycling of the original C&D waste. The chemical properties were established as dependent on the physical properties of the RCA. The RCA is then mixed with NA at the same replacement percentages together with other concrete constituents to produce the concrete used to examine fresh and hardened concrete properties. The fresh concrete properties investigated were: slump, slump loss, air content and fresh compacted density. The hardened concrete properties studied were: compressive strength, tensile splitting strength, oxygen permeability, water sorptivity, chloride conductivity, modulus of elasticity, shrinkage and creep. The concrete properties were not significantly influenced by the inclusion of RCA. According to the aggregate and concrete properties examined in this investigation, the full replacement of NA in structural concrete is possible and will improve the sustainable development of the construction industry. / AFRIKAANSE OPSOMMING: Die doel van hierdie navorsing is om ondersoek in te stel na die potensiele gebruik van growwe herwonne betonaggregaat (RCA) as ‘n materiaal in betonstruktuurontwerp. Die gebrek aan kennis en spesifikasies in Suid Afrika is die vernaamste rede vir hierdie navorsing van RCA. Deur die vermeerdering van die databasis van hierdie navorsing van RCA in Suid-Afrika kan die moontlikheid van spesifikasies vir hierdie alternatiewe boumateriaal geïnisieer word. Die implikasie van sodanige spesifikasies sou lei tot RCA aanvaarding in betonontwerp en dus die vermindering van die hoeveelhede konstruksie en sloping (C&D) van afvalversameling by stortterreine en om die ontginning van natuurlike aggregate te verminder. Die doelwitte wat deur hierdie navorsingsprojek bereik word is eerstens, wat is die vervangings persentasie van RCA in 'n betonmengsel wat produseer word wat dieselfde of beter resultate sal lewer as 'n betonmengsel wat uit natuurlike aggregate bestaan. Tweedens, watter aggregaat eienskappe en beperkings moet gedefinieer word in die spesifikasie van RCA sodat dit aanvaarbaar is as ‘n materiaal in betonstruktuur ontwerp. Die doelwitte word geassesseer deur die ondersoek van die geometriese, fisiese en chemiese eienskappe van die aggregaat as ‘n wesenlike materiaal en die vars en verharde betoneienskappe van RCA as ‘n bestanddeel in struktuurbetonontwerp. RCA monsters was geneem by ‘n kommersiele herwinningsfasiliteit wat RCA gebruik om betonsteen eenhede te vervaardig, is op drie verskillende tydperke ingesamel. Hierdie materiaal is herverwerk in die laboratorium om die gradering en die hoeveelheid van fyn materiaal wat nie deur die herwinningsproses beheer is nie. Die RCA was dan gekombineer met NA teen vervangingspersentasies van: 0, 15, 30, 50 en 100 % wat dan gebruik was om die eienskappe van die aggregaat te ondersoek. Daar is vasgestel dat die fisiese eienskappe van die RCA afhanklik van die geometriese eienskappe, met inagneming dat die geometriese eienskappe afhanklik is van die bron en metode van die herwinning van die oorspronklike C&D afval. Dit is gestig dat die chemise eienskappe is afhanklik van die fisiese eienskappe van die RCA. Die RCA is toe gemeng met NA teen dieselfde vervangingspersentasies saam met ander beton bestanddele om beton te produseer wat dan vergelyk kan word met vars en verharde beton eienskappe. Die volgende vars betoneienskappe is ondersoek: insinking, insinking verlies, luginhoud en vars gekompakteerde digtheid. Die volgende verharde betoneienskappe is bestudeer: druksterkte, trek die splintsing van krag, suurstofpermeabiliteit, water sorptiwiteit, chloride geleidingsvermoё, modulus van elastisiteit, krimp en kruip. Die beton eienskappe was nie beduidend beïnvloed deur die insluiting van RCA nie. Volgens die aggregate en beton eienskappe wat in hierdie navorsing ondersoek is, blyk dit dat die volle vervangingswaarde van NA in strukturele beton moontlik is en die volhoubare ontwikkeling van die konstruksiebedryf sal verbeter.
16

Single-Molecule Detection and Optical Scanning in Miniaturized Formats

Melin, Jonas January 2006 (has links)
<p>In later years polymer replication techniques have become a frequently employed fabrication method for microfluidic and micro-optical devices. This thesis describes applications and further developments of microstructures replicated in polymer materials. </p><p>A novel method for homogenous amplified single-molecule detection utilizing a microfluidic readout format is presented. The method enables enumeration of single biomolecules by transforming specific molecular recognition events at nanometer dimensions to micrometer-sized DNA macromolecules. This transformation process is mediated by target specific padlock probe ligation, followed by rolling circle amplification (RCA) resulting in the creation of one rolling circle product (RCP) for each recognized target. Throughout this transformation the discrete nature of the molecular population is preserved. By hybridizing a fluorescence-labeled DNA detection oligonucleotide to each repeated sequence of the RCP, a confined cluster of fluorophores is generated, which makes optical detection and quantification possible. Spectral multiplexing is also possible since the spectral profile of each RCP can be analyzed separately. The microfluidic data acquisition process is characterized in detail and conditions that allow for quantification limited only by Poisson sampling statistics is established. The molecular characteristics of RCPs in solution are also investigated.</p><p>Furthermore a novel thermoplastic microfluidic platform is described. The platform allows for observation of the microchannels using high magnification optics and also offers the possibility of on-chip cell culture and the integration of mechanical actuators.</p><p>A novel fabrication process for the integration of polymer micro-optical elements on silicon is presented. The process is used for fabrication of a micro-optical system consisting of a laser and a movable microlens making beam steering possible. Such a micro-scanning system could potentially be used for miniaturized biochemical analysis.</p>
17

Product Cycles for Sweden's Export of Machinery goods

Nömtak, Fredrika January 2005 (has links)
This thesis analyzes the product cycles of five different product groups within the Swedish machinery export during the time period 1964-2003. The result is that even though Sweden is a preferable region to launch new products and adopt new technologies, according to the product cycle models, the production is approaching a decreasing regional specialisation.
18

Single-Molecule Detection and Optical Scanning in Miniaturized Formats

Melin, Jonas January 2006 (has links)
In later years polymer replication techniques have become a frequently employed fabrication method for microfluidic and micro-optical devices. This thesis describes applications and further developments of microstructures replicated in polymer materials. A novel method for homogenous amplified single-molecule detection utilizing a microfluidic readout format is presented. The method enables enumeration of single biomolecules by transforming specific molecular recognition events at nanometer dimensions to micrometer-sized DNA macromolecules. This transformation process is mediated by target specific padlock probe ligation, followed by rolling circle amplification (RCA) resulting in the creation of one rolling circle product (RCP) for each recognized target. Throughout this transformation the discrete nature of the molecular population is preserved. By hybridizing a fluorescence-labeled DNA detection oligonucleotide to each repeated sequence of the RCP, a confined cluster of fluorophores is generated, which makes optical detection and quantification possible. Spectral multiplexing is also possible since the spectral profile of each RCP can be analyzed separately. The microfluidic data acquisition process is characterized in detail and conditions that allow for quantification limited only by Poisson sampling statistics is established. The molecular characteristics of RCPs in solution are also investigated. Furthermore a novel thermoplastic microfluidic platform is described. The platform allows for observation of the microchannels using high magnification optics and also offers the possibility of on-chip cell culture and the integration of mechanical actuators. A novel fabrication process for the integration of polymer micro-optical elements on silicon is presented. The process is used for fabrication of a micro-optical system consisting of a laser and a movable microlens making beam steering possible. Such a micro-scanning system could potentially be used for miniaturized biochemical analysis.
19

Development of novel multiplexed systems for in situ PLA

Broberg, John January 2011 (has links)
The in situ proximity ligation assay (in situ PLA) is an immunoassay that enables directvisualisation of single protein targets or protein interactions in cell or tissue samples. This project revolves around designing and introducing several novel multiplexable components tobe used in conjunction with Olink Bioscience's Duolink product line. In this report, a novel in silico approach to DNA oligomer interaction design is presented. Using this in silico method, a multiplexed system of DNA oligomers has been designed andevaluated using in situ PLA and fluorescence microscopy.
20

Product Cycles for Sweden's Export of Machinery goods

Nömtak, Fredrika January 2005 (has links)
<p>This thesis analyzes the product cycles of five different product groups within the Swedish machinery export during the time period 1964-2003.</p><p>The result is that even though Sweden is a preferable region to launch new products and adopt new technologies, according to the product cycle models, the production is approaching a decreasing regional specialisation.</p>

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