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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.
51

Systemutveckling och användbarhet -Att utnyttja användbarhetstester i systemutvecklingsprocessen / Systems development and usability -Using methods for testing usability during the system development process

Forsberg, Per, Klasson, Isak January 2002 (has links)
Den här rapporten behandlar frågeställningen om hur man kan anpassa systemutvecklingav ett informationssystem enligt livscykelmodellen till att inkludera användbarhetstester. Frågeställningen grundar sig i att god användbarhet inte är ett explicit uttryckt mål i Andersens beskrivning av livscykelmodellen. För att besvara frågeställningen har vi utvecklat och testat ett bokningssystem åt en mindre verksamhet. Utvecklingsarbetet har bedrivits enligt en egen anpassning av livscykelmodellen. Testerna har utförts enligt metoden cooperativ evaluation. Frågeställningen besvaras genom att vi presenterar hur vi har gått tillväga för att inbegripa testerna i utvecklingsprocessen. De delar av informationssystemet som vi utvärderat beskrivs i rapporten. Testerna hjälpte till att identifiera problem i systemets gränssnitt som annars troligen inte skulle ha upptäckts förrän slutanvändarna fått tillgång till systemet. Slutsatserna är att det är möjligt, och dessutom önskvärt ur användbarhetssynpunkt, att innefatta användbarhetstester i utveckling av informationssystem. / This reports regards the question of how one can adjust system development according to the Systems Development Life Cycle (SDLC) to include usability testing. The question is based on the fact that usability isn’t an explicit goal in Andersen description of the SDLC. To answer this question we have developed and tested an information system for a small business. The development has been carried on according to an own adaptation of the SDLC. The testings have been performed in accordance with the Cooperativ evaluation method. The question is answered by the presentation of our adaptation to include the tests in the development process. The parts of the information system we have evaluated are described in the report. The tests helped to identify problems in the user interface which otherwise probably would not have been discovered until the end user gotten access to the system. The conclusions are that it is possible, and furthermore desirable from a usability point of view, to include usability testing duringthe development of information systems.
52

Diagnostika poruch a vad podlah v bytové a občanské výstavbě / Diagnostics of flooring failures and defects in the housing and civic construction

Vrtal, Roman January 2014 (has links)
The object of the thesis is a description of preparation process, realization and subsequent treatment of floors based on calcium sulphate, including problems related to the issue. The aim of the work is to closely acquaint the reader with methods used in diagnostics of flooring failures and defects in the housing and civic construction, including practical applications of these methods on real structures. The work also includes experimental analysis of a real floor construction during local load effect.
53

Study of Vehicle-to-Pedestrian Interactions with FEM – Evaluation of Upper Leg Test Methods using a Human Body Model / Studie av Fotgängarkollisioner med FEM – Utvärdering av Testmetoder för Lårben/Höft med en Humanmodell

Morén, David, Pehrs, Georg January 2013 (has links)
The European New Car Assessment Programme (Euro NCAP) performs several different tests to evaluate vehicles and rate their safety. Some of these tests are subsystem tests made to mimic different body parts of a pedestrian in an interaction with a vehicle. However, some criticism to the test method for the upper leg has been presented, stating that there is a discrepancy between this test method and a real-life interaction. Therefore, a modified test method for the upper leg has been proposed. The aim of this thesis was to evaluate the upper leg test method used today by Euro NCAP, and compare it with the proposed modified test method as well as to computer simulations with a Human Body Model (HBM). The evaluation was performed by comparing different parameters obtained in the two test methods. These have also been compared to computer simulations using a HBM in interaction with a passenger vehicle model. Prior to the evaluation of the test methods, the HBM was positioned into different stances to mimic postures in the human walking cycle. The vehicle model was positioned at four different heights, and three different impact points along the bonnet were used. The results showed that the different methods had their own advantages for some parameters. However, no general conclusion of which method showed the closest correlation to the HBM reference simulations could be determined. / European New Car Assessment Programme (Euro NCAP) utför flera olika tester för att utvärdera fordon och betygsätta deras säkerhet. Några av dessa tester sker med delsystem skapade för att efterlikna olika kroppsdelar hos en fotgängare i en kollision med ett fordon. Viss kritik har dock riktats mot testmetoden för lårben och höft, då studier visat att det finns en skillnad mellan testmetoden och en verklig kollision. En modifierad testmetod för lårbenet och höften har därför föreslagits. Syftet med detta examensarbete har varit att utvärdera testmetoden för lårben och höft, som idag används av Euro NCAP, och jämföra den med den föreslagna modifierade testmetoden men även datorsimuleringar med en humanmodell. Utvärderingen har genomförts genom att jämföra olika parametrar som erhållits från de två testmetoderna. Dessa parametrar har även jämförts med datorsimuleringar av fotgängarkollisioner med en humanmodell och en bilmodell. Humanmodellen positionerades i olika kroppsställningar innan utvärderingen av testmetoderna genomfördes. Detta för att efterlikna verkliga positioner i en mänsklig gångcykel. Bilmodellen positionerades vid fyra olika höjder och tre träffpunkter längs motorhuven användes. Resultaten visade att båda metoderna hade fördelar gentemot varandra för vissa parametrar. Ingen generell slutsats kunde dock dras om vilken metod som visade närmast korrelation till referenssimuleringarna med humanmodellen.
54

Rückseitige Verstärkung von Stahlbetonplatten unter Impaktbeanspruchung

Bracklow, Franz 09 November 2022 (has links)
Im Rahmen der beschriebenen Arbeit erfolgt die experimentelle Untersuchung von nachträglich an Stahlbetonplatten aufgetragenen Verstärkungsschichten, die einer Impaktbelastung ausgesetzt werden. Die Grundlage hierfür bilden drei verschieden bewehrte Testserien, welche anhand eines entwickelten Versuchsschemas geprüft werden. Zielstellung ist die Quantifizierung der Leistungsfähigkeit rückseitig applizierter Verstärkungen sowie die Weiterentwicklung einer bereits existierenden Schädigungsbeschreibung und eines analytischen bzw. numerischen Modells.
55

Synthetic Gene Complementation to Determine off-Target Silencing

Kumar, Dhirendra R. 01 January 2015 (has links)
RNA interference (RNAi) is a conserved mechanism in a wide range of eukaryotes. Introduction of synthetic dsRNA could specifically target suppression of a gene or could result in off-target silencing of another gene due to sequence similarity. To verify if the observed phenotype in an RNAi transgenic line is due to silencing of a specific gene or if it is due to another nontarget gene, a synthetic gene complementation approach could be used. Synthetic gene complementation described in this method uses the technology of synthesizing a variant of a native gene (used in RNAi silencing) to maximize the difference in DNA sequences while coding for the exact same amino acids as the original native gene. This is achieved through the use of alternate codons. The new variant gene is expressed in the original RNAi transgenic lines and analyzed for complementation of the RNAi phenotype. Complementation of the RNAi-induced phenotype will indicate gene-specific silencing and not off-target silencing.
56

Method development for testing propulsion batteries at a workshop : Parameter identification through experiments and investigation of challenges with workshop implementation / Metodutveckling för test av batterier vid verkstad : Parameteridentifikation genom experiment och studie om utmaningar för verkstadsimplementering

Strinnholm, Kim January 2020 (has links)
The electrification within the automotive industry goes faster than ever, which drives an increased demand for more knowledge about batteries. Vehicle manufacturers should be able to tell how long the batteries will last and have a service program for electrified vehicles, just as there is for traditional, fuel-driven ones. Scania is in the process of developing new service methods for their hybrids and fully electrified vehicles where this thesis has been a part of this development by investigating the possibilities of having a workshop test to measure the capacity of the propulsion batteries.  During the thesis, essential parameters for cycling the batteries and measure the capacity with high accuracy have been identified and investigated by conducting lab tests. In parallel to defining the properties of a successful capacity measurement, the implementation of such a measurement at a workshop has been studied alongside a brief discussion about scheduling strategies. Conducting a capacity measurement in a workshop environment introduce new challenges, and the critical question arises, how long can the capacity measurement take? It is identified that the state of charge window size, the temperature, and the relaxation time are essential parameters to control. From the experimental part of the thesis, it can be concluded that the start temperature should lay in the range of 15-25 °C with a relaxation time of 5-10 minutes providing a satisfying accuracy. A SOC window size of 20-80% seems to be the most optimal balance between time spent and accuracy in the measurement. Furthermore, it is identified that the workshop's equipment is heavily influencing the time it takes to conduct a test. It is concluded that it is necessary to be able to charge and discharge the batteries. / Elektrifieringen av fordons industrin går snabbare än någonsin, vilket driver en högre efterfrågan på mer kunskap om batterier. Fordons tillverkare ska kunna redogöra för hur länge batterierna kan användas och ha ett service program för elektrifierade fordon, likt det som redan finns för traditionella, bränsledrivna fordon. Scania håller på att utveckla nya service metoder för sina hybrider och elektriska fordon där detta examensarbete har varit en del av denna utveckling genom att undersöka möjligheterna kring en verkstadsmetod för att mäta kapaciteten hos framdrivnings batterier.  Under examensarbetet har väsentliga parametrar för cykling av batterier och mätning av kapacitet med hög noggrannhet identifierats och undersökts med laboratorietester. Parallellt med arbetet för att definiera egenskaperna hos en precis kapacitets mätning har implementationen av en sådan mätning i en verkstad studerats tillsammans med en kort diskussion om strategier för schemaläggning av dessa tester. Det introducerar nya utmaningar att utföra kapacitets mätningen i en verkstad och den viktiga frågan uppstår, hur lång tid tar en sådan kapacitets mätning? Det har identifieras att SOC fönster storleken, temperaturen och relaxeringstiden är essentiella parametrar att kontrollera. Slutsatserna är att temperaturen bör ligga i intervallet 15-25 °C med en relaxeringstid på 5-10 minuter ger en tillfredställande noggrannhet. Ett SOC fönster motsvarande 20-80% är förefaller vara den mest optimala i avvägningen mellan tidsåtgång och precision. Vidare kan den tillgängliga utrustningen på verkstaden pekas ut som en starkt påverkande faktor till tiden det tar att utföra ett sådant verkstadstest.
57

Validação do Teste de ativação de basófilos no diagnóstico de reações de hipersensibilidade a anti-inflamatórios não esteroidais / Validation of basophil activation test for the diagnosis of hypersensitivity reactions to nonsteroidal antiinflammatory drugs

Misumi, Denise Shimbo 10 May 2013 (has links)
Introdução: Atualmente, o diagnóstico das reações de hipersensibilidade a anti-inflamatórios não esteroidais (AINEs) baseia-se na história relatada pelo paciente e, em determinados casos, é realizado o Teste de Provocação. Todavia, este teste pode expor os pacientes a riscos graves, inclusive anafilaxia. Em busca de ferramenta mais segura, tem-se estudado o Teste de Ativação de Basófilos (BAT). Trata-se de um teste in vitro, no qual é possível testar diversos estímulos em uma única amostra de sangue, avaliando a ativação dos basófilos (indicativo de reação de hipersensibilidade), através do aumento da expressão de moléculas na superfície desses leucócitos, como o CD63. Objetivo: Padronizar e validar o BAT para ácido acetilsalicílico (AAS), diclofenaco, dipirona e paracetamol em pacientes com hipersensibilidade a AINEs. Metodologia: Participaram 20 (testados com os quatro AINEs) + 33 (testados somente com AAS) pacientes atendidos no Serviço de Imunologia Clínica e Alergia do HCFMUSP, que apresentaram manifestações cutâneas em até 24 horas após exposição a um ou múltiplos AINEs, bem como 13 (quatro AINEs) + 26 (AAS) controles. A técnica consistiu em incubar sangue total com os AINEs já mencionados e, depois, marcar as amostras com anticorpos monoclonais (CD45, anti-IgE e CD63) para posterior leitura por citometria de fluxo. Os resultados obtidos foram comparados com as histórias clínicas e os testes de provocação oral, quando realizados. Resultados: Utilizando os critérios de positividade do BAT empregados na literatura (isto é, porcentagem de CD45+IgE+highCD63+ e índice de estimulação), a sensibilidade e a especificidade variaram de acordo com o AINE: para ácido acetilsalicílico foram 75,0% e 16,7%, respectivamente, diclofenaco, 100% e 0%, dipirona, 23,5% e 66,7%, paracetamol, 40,0% e 42,9%. Após a realização de curvas dose-resposta e tempo-resposta somente com AAS, foi encontrado novo critério de positividade: média de intensidade de fluorescência (MFI) menor do que 6575 representava BAT positivo; com isso, os valores de sensibilidade e especificidade foram: 84,4% e 34,6%, respectivamente. O BAT foi mais sensível em pacientes cuja última reação ocorreu há menos de um ano da data de execução do BAT (93,7%). Conclusão: Devido aos baixos valores de sensibilidade e/ou especificidade, não foi possível padronizar e, por conseguinte, validar o BAT para ácido acetilsalicílico, diclofenaco, dipirona e paracetamol. / Introduction: Currently, the diagnosis of nonsteroidal antiinflammatory drugs (NSAIDs) hypersensivitity is based on patients´ clinical history and drug provocation tests, which are done in selected cases. Nevertheless, this test may expose patients to severe risks, including anaphylaxis. Looking for a safer tool, Basophil Activation Test (BAT) for allergy diagnosis has been studied in the last years. It is an in vitro method where a wide variety of stimuli can be tested, incubating them with the patient\'s blood sample, and observing basophil activation (indication of hypersensitivity) through upregulation of CD63 (or other basophil activation markers) on this leucocyte\'s membrane. Objective: To standardize and validate BAT stimulated with acetylsalicylic acid (ASA), diclophenac, dipyrone and paracetamol in NSAID hypersensitive patients. Methods: Patients which reported immediate reactions (less than 24 hours) after exposure to one or multiple NSAIDs, with cutaneous symptoms were enrolled from Clinical Immunology and Allergy outpatient clinic from HC-FMUSP. BAT with the four NSAIDs was tested on 20 patients and 13 controls and BAT with ASA only, on 33 patients and 26 controls. BAT consisted of incubating whole blood with NSAIDs, then triple-labeled with monoclonal antibodies (CD45, anti-IgE, CD63) for analysis by flow cytometry. BAT results were compared to clinical history and oral provocation tests, when available. Results: According to literature\'s positivity criteria (percentage of CD45+IgE+highCD63+ and stimulation index), sensitivity and specificity varied according to the NSAID tested: for ASA was 75.0% and 16.7% respectively, diclophenac, 100.0% and 0.0%, dipyrone, 23.5% and 66.7%, paracetamol, 40.0% and 42.9%. A new positivity criterion was possible to be defined after further dose-response and time-response curves only for ASA: Mean Fluorescence Intensity lower than 6575 (positive BAT). Accordingly, new sensitivity and specificity for BAT in ASA hypersensitivity were 84,4% and 34,6%. Patients that presented the last reaction in the last year were more likely to present a positive BAT (93.7%). Conclusion: Due to low values for sensitivity and/or specificity, it was not possible to standardize and validate BAT for ASA, diclophenac, dipyrone and paracetamol.
58

The rate-limiting mechanism for the heterogeneous burning of iron in normal gravity and reduced gravity

Ward, Nicholas Rhys January 2007 (has links)
This thesis presents a research project in the field of oxygen system fire safety relating to the heterogeneous burning of iron in normal gravity and reduced gravity. Fires involving metallic components in oxygen systems often occur, with devastating and costly results, motivating continued research to improve the safety of these devices through a better understanding of the burning phenomena. Metallic materials typically burn in the liquid phase, referred to as heterogeneous burning. A review of the literature indicates that there is a need to improve the overall understanding of heterogeneous burning and better understand the factors that influence metal flammability in normal gravity and reduced gravity. Melting rates for metals burning in reduced gravity have been shown to be higher than those observed under similar conditions in normal gravity, indicating that there is a need for further insight into heterogeneous burning, especially in regard to the rate-limiting mechanism. The objective of the current research is to determine the cause of the higher melting rates observed for metals burning in reduced gravity to (a) identify the rate-limiting mechanism during heterogeneous burning and thus contribute to an improved fundamental understanding of the system, and (b) contribute to improved oxygen system fire safety for both ground-based and space-based applications. In support of the work, a 2-s duration ground-based drop tower reduced-gravity facility was commissioned and a reduced-gravity metals combustion test system was designed, constructed, commissioned and utilised. These experimental systems were used to conduct tests involving burning 3.2-mm diameter cylindrical iron rods in high-pressure oxygen in normal gravity and reduced gravity. Experimental results demonstrate that at the onset of reduced gravity, the burning liquid droplet rapidly attains a spherical shape and engulfs the solid rod, and that this is associated with a rapid increase in the observed melting rate. This link between the geometry of the solid/liquid interface and melting rate during heterogeneous burning is of particular interest in the current research. Heat transfer analysis was performed and shows that a proportional relationship exists between the surface area of the solid/liquid interface and the observed melting rate. This is confirmed through detailed microanalysis of quenched samples that shows excellent agreement between the proportional change in interfacial surface area and the observed melting rate. Thus, it is concluded that the increased melting rates observed for metals burning in reduced gravity are due to altered interfacial geometry, which increases the contact area for heat transfer between the liquid and solid phases. This leads to the conclusion that heat transfer across the solid/liquid interface is the rate-limiting mechanism for melting and burning, limited by the interfacial surface area. This is a fundamental result that applies in normal gravity and reduced gravity and clarifies that oxygen availability, as postulated in the literature, is not rate limiting. It is also established that, except for geometric changes at the solid/liquid interface, the heterogeneous burning phenomenon is the same at each gravity level. A conceptual framework for understanding and discussing the many factors that influence heterogeneous burning is proposed, which is relevant to the study of burning metals and to oxygen system fire safety in both normal-gravity and reduced-gravity applications.
59

Validação do Teste de ativação de basófilos no diagnóstico de reações de hipersensibilidade a anti-inflamatórios não esteroidais / Validation of basophil activation test for the diagnosis of hypersensitivity reactions to nonsteroidal antiinflammatory drugs

Denise Shimbo Misumi 10 May 2013 (has links)
Introdução: Atualmente, o diagnóstico das reações de hipersensibilidade a anti-inflamatórios não esteroidais (AINEs) baseia-se na história relatada pelo paciente e, em determinados casos, é realizado o Teste de Provocação. Todavia, este teste pode expor os pacientes a riscos graves, inclusive anafilaxia. Em busca de ferramenta mais segura, tem-se estudado o Teste de Ativação de Basófilos (BAT). Trata-se de um teste in vitro, no qual é possível testar diversos estímulos em uma única amostra de sangue, avaliando a ativação dos basófilos (indicativo de reação de hipersensibilidade), através do aumento da expressão de moléculas na superfície desses leucócitos, como o CD63. Objetivo: Padronizar e validar o BAT para ácido acetilsalicílico (AAS), diclofenaco, dipirona e paracetamol em pacientes com hipersensibilidade a AINEs. Metodologia: Participaram 20 (testados com os quatro AINEs) + 33 (testados somente com AAS) pacientes atendidos no Serviço de Imunologia Clínica e Alergia do HCFMUSP, que apresentaram manifestações cutâneas em até 24 horas após exposição a um ou múltiplos AINEs, bem como 13 (quatro AINEs) + 26 (AAS) controles. A técnica consistiu em incubar sangue total com os AINEs já mencionados e, depois, marcar as amostras com anticorpos monoclonais (CD45, anti-IgE e CD63) para posterior leitura por citometria de fluxo. Os resultados obtidos foram comparados com as histórias clínicas e os testes de provocação oral, quando realizados. Resultados: Utilizando os critérios de positividade do BAT empregados na literatura (isto é, porcentagem de CD45+IgE+highCD63+ e índice de estimulação), a sensibilidade e a especificidade variaram de acordo com o AINE: para ácido acetilsalicílico foram 75,0% e 16,7%, respectivamente, diclofenaco, 100% e 0%, dipirona, 23,5% e 66,7%, paracetamol, 40,0% e 42,9%. Após a realização de curvas dose-resposta e tempo-resposta somente com AAS, foi encontrado novo critério de positividade: média de intensidade de fluorescência (MFI) menor do que 6575 representava BAT positivo; com isso, os valores de sensibilidade e especificidade foram: 84,4% e 34,6%, respectivamente. O BAT foi mais sensível em pacientes cuja última reação ocorreu há menos de um ano da data de execução do BAT (93,7%). Conclusão: Devido aos baixos valores de sensibilidade e/ou especificidade, não foi possível padronizar e, por conseguinte, validar o BAT para ácido acetilsalicílico, diclofenaco, dipirona e paracetamol. / Introduction: Currently, the diagnosis of nonsteroidal antiinflammatory drugs (NSAIDs) hypersensivitity is based on patients´ clinical history and drug provocation tests, which are done in selected cases. Nevertheless, this test may expose patients to severe risks, including anaphylaxis. Looking for a safer tool, Basophil Activation Test (BAT) for allergy diagnosis has been studied in the last years. It is an in vitro method where a wide variety of stimuli can be tested, incubating them with the patient\'s blood sample, and observing basophil activation (indication of hypersensitivity) through upregulation of CD63 (or other basophil activation markers) on this leucocyte\'s membrane. Objective: To standardize and validate BAT stimulated with acetylsalicylic acid (ASA), diclophenac, dipyrone and paracetamol in NSAID hypersensitive patients. Methods: Patients which reported immediate reactions (less than 24 hours) after exposure to one or multiple NSAIDs, with cutaneous symptoms were enrolled from Clinical Immunology and Allergy outpatient clinic from HC-FMUSP. BAT with the four NSAIDs was tested on 20 patients and 13 controls and BAT with ASA only, on 33 patients and 26 controls. BAT consisted of incubating whole blood with NSAIDs, then triple-labeled with monoclonal antibodies (CD45, anti-IgE, CD63) for analysis by flow cytometry. BAT results were compared to clinical history and oral provocation tests, when available. Results: According to literature\'s positivity criteria (percentage of CD45+IgE+highCD63+ and stimulation index), sensitivity and specificity varied according to the NSAID tested: for ASA was 75.0% and 16.7% respectively, diclophenac, 100.0% and 0.0%, dipyrone, 23.5% and 66.7%, paracetamol, 40.0% and 42.9%. A new positivity criterion was possible to be defined after further dose-response and time-response curves only for ASA: Mean Fluorescence Intensity lower than 6575 (positive BAT). Accordingly, new sensitivity and specificity for BAT in ASA hypersensitivity were 84,4% and 34,6%. Patients that presented the last reaction in the last year were more likely to present a positive BAT (93.7%). Conclusion: Due to low values for sensitivity and/or specificity, it was not possible to standardize and validate BAT for ASA, diclophenac, dipyrone and paracetamol.

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