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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.
1

Volunteer Glyphosate-Resistant Corn (Zea Mays) Control and Competition in Glyphosate-Resistant Cotton (Gossypium Hirsutum)

Storey, Reed Collins 17 August 2013 (has links)
Adoption of glyphosate-resistant crops has resulted in increased glyphosate usage and decreased use of residual herbicides thus resulting in weed pressure shifts. Weeds that display multiple-resistance to glyphosate and other herbicide modes of action have become a concern in many parts of the United States. Incorporation of multiple herbicide resistance traits into multiple cropping systems, may facilitate weed resistance to additional herbicides. Furthermore, controlling volunteer crop stands containing multiple herbicide-resistance traits may be problematic in herbicide resistant crops. These volunteer crops will compete with the currently growing crop qualifying them as a weed. Therefore, this research was conducted to determine control options for: failed glyphosate resistant corn stands, and volunteer glyphosate resistant corn stands in glyphosate resistant cotton. Furthermore, research was conducted to determine what densities of glyphosate-resistant corn will cause cotton yield loss and if time of removal of these densities impacts cotton yield loss.
2

Non-catalytic after-treatment for diesel particulates using carbon-fiber filter and experimental validation

Matsui, Kenta, Fujikake, Fumihiro, Yamamoto, Kazuhiro January 2013 (has links)
No description available.
3

Seguimento pós-tratamento primário para neoplasia de colo uterino : análise crítica

Hillesheim, Ingrid Cruz January 2012 (has links)
Introdução: Após o tratamento primário do câncer invasor de colo de útero, não existe protocolo de seguimento rigorosamente definido para essas pacientes. O tipo de acompanhamento dessas mulheres é individualizado, e não há consenso sobre a melhor estratégia a ser adotada. Objetivo: Avaliar o papel dos exames de seguimento (exame físico, citologia e exames de imagens) pós-tratamento de neoplasia de colo uterino no diagnóstico de recidivas assintomáticas e sintomáticas. Material e métodos: Foram revisados todos os prontuários das pacientes com diagnóstico de câncer de colo uterino desde 1985 até 2010. Nesse período, houve um total de 359 pacientes elegíveis para o estudo, sendo 64 destas com recidiva tumoral. Todas as análises estatísticas foram realizadas com a ajuda do programa SPSS v.18.0. Foi considerado um nível de significância de 5%. Resultados: Das 359 pacientes consideradas para o estudo, 64 (17,8%) apresentaram recidiva tumoral. Destas, 34 (53,1%) foram sintomáticas, e 30 (46,9%), assintomáticas. A maioria das pacientes teve sua recidiva diagnosticada através do exame físico, tanto no grupo das pacientes sintomáticas (50%) como no das assintomáticas (66,7%) (p = 0000). O exame citopatológico foi o responsável pela detecção da recidiva em somente um caso em ambos os grupos, correspondendo a 2,9 e 3,3%, respectivamente (p = 0000). Os exames de imagem (raio X de tórax, tomografia abdominal, ecografia abdominal, cintilografia óssea) somam 10 casos (29,4%) dos diagnósticos nas pacientes sintomáticas e oito casos (26,6%) nas assintomáticas (p = 0000). Não houve diferença estatisticamente significativa entre os grupos ou entre os diferentes métodos de detecção de recidiva. Ajustando para potenciais fatores de confusão, como a idade e o tipo de tratamento, também não houve associação. Conclusão: O grande sinalizador de recidiva tumoral neste estudo foi o exame físico. Nenhum dos exames coadjuvantes foi capaz de detectar as recorrências, tanto nas pacientes sintomáticas como nas assintomáticas. Esses resultados mostram a grande necessidade de estudos prospectivos que comparem a efetividade de diferentes regimes de seguimento que avaliem questões como a sobrevida global e a qualidade de vida. / Introduction: There is no strictly defined follow-up protocol for patients who have undergone primary treatment for invasive cervical cancer. These women are managed on a case-by-case basis and there is no consensus on the first-choice strategy. Objective: To evaluate the role played by follow-up tests and examinations (physical examination, cytology and imaging exams) in diagnosing symptomatic and asymptomatic relapses after treatment for neoplasms of the cervix. Materials and Methods: Data were collected from medical records for all patients diagnosed with cervical cancer from 1985 to 2010. There were a total of 359 eligible patients during that period, 64 of whom had tumor relapses. All statistical analyses were performed with the aid of SPSS v.18.0. The significance level adopted was 5%. Results: Sixty-four (17.8%) of the 359 patients investigated suffered tumor relapse. Thirty-four (53.1%) were symptomatic and 30 (46.9%) were asymptomatic. A majority of patients had tumor relapse diagnosed during physical examination, both among the symptomatic patients (50%), and the asymptomatic patients (66.7%) (p = 0.274). Cytopathology was responsible for detecting relapse in just 1 case in each group, corresponding to 2.9 and 3.3%, respectively (p = 0.999 Imaging exams (chest X-ray, abdominal tomography, abdominal ultrasound, bone scintigraphy) detected 10 (29.4%) relapses among symptomatic patients and 8 cases (26.6%) among asymptomatic patients (p = 0.770). There were no statistically significant differences between the two groups or between the different methods of detecting relapses. There was still no association after adjustment for potential confounding factors such as age and type of treatment. Conclusions: Physical examination was the preeminent method for detecting tumor relapse in this study. None of the other tests or exams were capable of detecting relapses in both symptomatic and asymptomatic patients. These results highlights the urgent need for prospective studies that compare the efficacy of different follow-up regimes, analyzing factors such as global survival and quality of life.
4

Seguimento pós-tratamento primário para neoplasia de colo uterino : análise crítica

Hillesheim, Ingrid Cruz January 2012 (has links)
Introdução: Após o tratamento primário do câncer invasor de colo de útero, não existe protocolo de seguimento rigorosamente definido para essas pacientes. O tipo de acompanhamento dessas mulheres é individualizado, e não há consenso sobre a melhor estratégia a ser adotada. Objetivo: Avaliar o papel dos exames de seguimento (exame físico, citologia e exames de imagens) pós-tratamento de neoplasia de colo uterino no diagnóstico de recidivas assintomáticas e sintomáticas. Material e métodos: Foram revisados todos os prontuários das pacientes com diagnóstico de câncer de colo uterino desde 1985 até 2010. Nesse período, houve um total de 359 pacientes elegíveis para o estudo, sendo 64 destas com recidiva tumoral. Todas as análises estatísticas foram realizadas com a ajuda do programa SPSS v.18.0. Foi considerado um nível de significância de 5%. Resultados: Das 359 pacientes consideradas para o estudo, 64 (17,8%) apresentaram recidiva tumoral. Destas, 34 (53,1%) foram sintomáticas, e 30 (46,9%), assintomáticas. A maioria das pacientes teve sua recidiva diagnosticada através do exame físico, tanto no grupo das pacientes sintomáticas (50%) como no das assintomáticas (66,7%) (p = 0000). O exame citopatológico foi o responsável pela detecção da recidiva em somente um caso em ambos os grupos, correspondendo a 2,9 e 3,3%, respectivamente (p = 0000). Os exames de imagem (raio X de tórax, tomografia abdominal, ecografia abdominal, cintilografia óssea) somam 10 casos (29,4%) dos diagnósticos nas pacientes sintomáticas e oito casos (26,6%) nas assintomáticas (p = 0000). Não houve diferença estatisticamente significativa entre os grupos ou entre os diferentes métodos de detecção de recidiva. Ajustando para potenciais fatores de confusão, como a idade e o tipo de tratamento, também não houve associação. Conclusão: O grande sinalizador de recidiva tumoral neste estudo foi o exame físico. Nenhum dos exames coadjuvantes foi capaz de detectar as recorrências, tanto nas pacientes sintomáticas como nas assintomáticas. Esses resultados mostram a grande necessidade de estudos prospectivos que comparem a efetividade de diferentes regimes de seguimento que avaliem questões como a sobrevida global e a qualidade de vida. / Introduction: There is no strictly defined follow-up protocol for patients who have undergone primary treatment for invasive cervical cancer. These women are managed on a case-by-case basis and there is no consensus on the first-choice strategy. Objective: To evaluate the role played by follow-up tests and examinations (physical examination, cytology and imaging exams) in diagnosing symptomatic and asymptomatic relapses after treatment for neoplasms of the cervix. Materials and Methods: Data were collected from medical records for all patients diagnosed with cervical cancer from 1985 to 2010. There were a total of 359 eligible patients during that period, 64 of whom had tumor relapses. All statistical analyses were performed with the aid of SPSS v.18.0. The significance level adopted was 5%. Results: Sixty-four (17.8%) of the 359 patients investigated suffered tumor relapse. Thirty-four (53.1%) were symptomatic and 30 (46.9%) were asymptomatic. A majority of patients had tumor relapse diagnosed during physical examination, both among the symptomatic patients (50%), and the asymptomatic patients (66.7%) (p = 0.274). Cytopathology was responsible for detecting relapse in just 1 case in each group, corresponding to 2.9 and 3.3%, respectively (p = 0.999 Imaging exams (chest X-ray, abdominal tomography, abdominal ultrasound, bone scintigraphy) detected 10 (29.4%) relapses among symptomatic patients and 8 cases (26.6%) among asymptomatic patients (p = 0.770). There were no statistically significant differences between the two groups or between the different methods of detecting relapses. There was still no association after adjustment for potential confounding factors such as age and type of treatment. Conclusions: Physical examination was the preeminent method for detecting tumor relapse in this study. None of the other tests or exams were capable of detecting relapses in both symptomatic and asymptomatic patients. These results highlights the urgent need for prospective studies that compare the efficacy of different follow-up regimes, analyzing factors such as global survival and quality of life.
5

Elaboration d'un système de dépollution adapté aux appareils de chauffage domestique au bois / Conception of a new after treatment system adapted to small wood burning appliances

Hector, Gilles 16 May 2012 (has links)
Les contextes climatique et énergétique mondiaux encouragent les pays de l'Union Européenne à améliorer leurs impacts environnementaux. Un des objectifs consiste à diminuer les émissions de CO2 en développant les énergies renouvelables. En France, la filière bois énergie représente la première source d'énergie renouvelable avec une production s'élevant à 10 MTep par an. Toutefois, il est indispensable de ne pas se limiter aux émissions de CO2 pour déterminer l'impact global d'une source d'énergie. En effet, la combustion de bois dans les appareils de chauffage domestique tels que les poêles, les inserts, les foyers ouverts, est à l'origine d'une part non négligeable de certains polluants atmosphériques tels que le CO, les COV, les HAP et les particules fines. L'objectif de ce projet est de réaliser un système efficace de dépollution capable de traiter l'ensemble des polluants à la sortie de ces appareils de chauffage. Des technologies sont déjà disponibles pour la dépollution des fumées issues de différentes sources de combustion, néanmoins nous devons intégrer les problématiques liées au fonctionnement de ces appareils ainsi que des critères de coût, de fonctionnalité et de développement durable définis dans un cahier des charges réalisé avec le partenaire industriel. Le travail réalisé nous à permis de concevoir et de tester un système complet capable de traiter tant les composants gazeux à l'aide d'un catalyseur à base de fer imprégné sur de la cérine, que les particules grâce à un lit filtrant régénéré par microondes. Le système décrit dans ce manuscrit présente une réduction faible des émissions, mais a permis de mettre en lumière les contraintes et les espoirs d'un futur système de traitement efficient. / The global energy and climate contexts encourage EU countries to improve their environmental impacts. One goal is to reduce CO2 emissions by developing the use of renewable energies. In France, wood is the first renewable energy source with an equivalent of 10 Mtoe produced each year. However, it is essential to study the global environment impact of on this energy source including CO2 emissions but also the different pollutants emitted. Indeed, the combustion of wood in small home heating units as stoves, open and closed fireplaces, is responsible for a significant part of typical air pollutants such as CO, VOCs, PAHs and fine particles. The objective of this project is to develop an effective system able to treat both pollutants emittedfrom those heaters. Few technologies are already available for smoke after treatment. However, we must incorporate in our study constraints related to the operation of these wood heating devices as well as criteria of cost, functionality and sustainability defined in the specifications set with the industrial partner of this project. The result of the work performed in this project was the conception of a complete prototype tested for emissions reduction. The system is composed of ceria impregnated iron catalyst for gaseous compounds oxidation and a microwave regenerated bed filter for particles elimination. The tests performed on the prototype showed weak emissions abatement. Nevertheless, this project highlighted constraints and hopes for a future efficient after treatment system.
6

Seguimento pós-tratamento primário para neoplasia de colo uterino : análise crítica

Hillesheim, Ingrid Cruz January 2012 (has links)
Introdução: Após o tratamento primário do câncer invasor de colo de útero, não existe protocolo de seguimento rigorosamente definido para essas pacientes. O tipo de acompanhamento dessas mulheres é individualizado, e não há consenso sobre a melhor estratégia a ser adotada. Objetivo: Avaliar o papel dos exames de seguimento (exame físico, citologia e exames de imagens) pós-tratamento de neoplasia de colo uterino no diagnóstico de recidivas assintomáticas e sintomáticas. Material e métodos: Foram revisados todos os prontuários das pacientes com diagnóstico de câncer de colo uterino desde 1985 até 2010. Nesse período, houve um total de 359 pacientes elegíveis para o estudo, sendo 64 destas com recidiva tumoral. Todas as análises estatísticas foram realizadas com a ajuda do programa SPSS v.18.0. Foi considerado um nível de significância de 5%. Resultados: Das 359 pacientes consideradas para o estudo, 64 (17,8%) apresentaram recidiva tumoral. Destas, 34 (53,1%) foram sintomáticas, e 30 (46,9%), assintomáticas. A maioria das pacientes teve sua recidiva diagnosticada através do exame físico, tanto no grupo das pacientes sintomáticas (50%) como no das assintomáticas (66,7%) (p = 0000). O exame citopatológico foi o responsável pela detecção da recidiva em somente um caso em ambos os grupos, correspondendo a 2,9 e 3,3%, respectivamente (p = 0000). Os exames de imagem (raio X de tórax, tomografia abdominal, ecografia abdominal, cintilografia óssea) somam 10 casos (29,4%) dos diagnósticos nas pacientes sintomáticas e oito casos (26,6%) nas assintomáticas (p = 0000). Não houve diferença estatisticamente significativa entre os grupos ou entre os diferentes métodos de detecção de recidiva. Ajustando para potenciais fatores de confusão, como a idade e o tipo de tratamento, também não houve associação. Conclusão: O grande sinalizador de recidiva tumoral neste estudo foi o exame físico. Nenhum dos exames coadjuvantes foi capaz de detectar as recorrências, tanto nas pacientes sintomáticas como nas assintomáticas. Esses resultados mostram a grande necessidade de estudos prospectivos que comparem a efetividade de diferentes regimes de seguimento que avaliem questões como a sobrevida global e a qualidade de vida. / Introduction: There is no strictly defined follow-up protocol for patients who have undergone primary treatment for invasive cervical cancer. These women are managed on a case-by-case basis and there is no consensus on the first-choice strategy. Objective: To evaluate the role played by follow-up tests and examinations (physical examination, cytology and imaging exams) in diagnosing symptomatic and asymptomatic relapses after treatment for neoplasms of the cervix. Materials and Methods: Data were collected from medical records for all patients diagnosed with cervical cancer from 1985 to 2010. There were a total of 359 eligible patients during that period, 64 of whom had tumor relapses. All statistical analyses were performed with the aid of SPSS v.18.0. The significance level adopted was 5%. Results: Sixty-four (17.8%) of the 359 patients investigated suffered tumor relapse. Thirty-four (53.1%) were symptomatic and 30 (46.9%) were asymptomatic. A majority of patients had tumor relapse diagnosed during physical examination, both among the symptomatic patients (50%), and the asymptomatic patients (66.7%) (p = 0.274). Cytopathology was responsible for detecting relapse in just 1 case in each group, corresponding to 2.9 and 3.3%, respectively (p = 0.999 Imaging exams (chest X-ray, abdominal tomography, abdominal ultrasound, bone scintigraphy) detected 10 (29.4%) relapses among symptomatic patients and 8 cases (26.6%) among asymptomatic patients (p = 0.770). There were no statistically significant differences between the two groups or between the different methods of detecting relapses. There was still no association after adjustment for potential confounding factors such as age and type of treatment. Conclusions: Physical examination was the preeminent method for detecting tumor relapse in this study. None of the other tests or exams were capable of detecting relapses in both symptomatic and asymptomatic patients. These results highlights the urgent need for prospective studies that compare the efficacy of different follow-up regimes, analyzing factors such as global survival and quality of life.
7

Gynekologisk cancer : En litteraturstudie om kvinnors erfarenheter efter avslutad behandling

Fockström, Anna, Ingmarsson, Melinda January 2021 (has links)
Bakgrund: I Sverige drabbas cirka 3000 kvinnor varje år av gynekologisk cancer. Cancer i kvinnans reproduktionsorgan innefattar cancer i äggstockarna, livmodern, livmoderhalsen, vulva och vaginan. Vanligtvis behandlas dessa cancerformer med cytostatika, strålbehandling, kirurgi eller hormonbehandling. Kvinnorna behandlas med kombinerade eller enskilda behandlingsformer beroende på cancerns form och stadium. Syfte: Syftet med denna studie var att beskriva kvinnors erfarenheter av gynekologisk cancer efter avslutad behandling. Metod: En beskrivande litteraturstudie innehållande 15 artiklar med både kvantitativa och kvalitativa ansatser samt mixed-methods. Dessa artiklar har sökts fram i databasen Medline via PubMed. Huvudresultat: Kvinnorna hade både negativa och i sällsynta fall även positiva erfarenheter efter en gynekologisk cancerbehandling. Oavsett om det var positiva eller negativa erfarenheter orsakade de förändringar i kvinnornas liv. Dessa förändringar innebar psykiska, fysiska och sociala konsekvenser som kvinnorna fick leva med under en längre tid. Slutsats: Även om kvinnornas erfarenheter var individuella upplevde många kvinnor liknande konsekvenser efter behandlingen mot gynekologisk cancer. Kvinnorna påverkades psykiskt, fysiskt och socialt vilket ledde till förändringar i deras liv. Sjuksköterskan hade en central roll i kvinnans möte med vården och sjuksköterskan bör eftersträva bästa möjliga omvårdnad för den unika kvinnan. / Background: About 3000 women are affected by gynecological cancer in Sweden every year. Cancer in female genitals includes cancer of the ovaries, uterus, cervix, vagina and vulva. These cancers are usually treated with chemotherapy, radiation, surgery or hormone treatment. The women are treated with combined or individual treatments depending on the type and stage of the cancer. Aim: The aim of this study was to describe women's experiences of gynecological cancer after the treatment was concluded. Methods: This study is a descriptive literature study containing 15 articles with both quantitative and qualitative approaches and mixed-methods. These articles have been searched in the database Medline through PubMed. Results: The women experienced both negative and in rare cases also positive experiences after a gynecological cancer treatment. Whether it was positive or negative experiences it caused changes in women’s lives. These changes entailed psychological, physical and social consequences that the women had to live with for a long time. Conclusion: Although the women’s experiences were individual, many women experienced similar consequences after treatment for gynecological cancer. The women were affected menatally, physically and socially which led to changes in their lives. The nurse had a central role in the women's encounter with the care and the nurses should strive for the best possible care for the unique woman.
8

Transient Flow Simulations in Exhaust After Treatment Systems

Walder, John January 2020 (has links)
The exhaust after treatment system is responsible for removing particulates and contaminants from the exhaust gases. The flow entering the SCR, a catalyst utilizing ammonia to reduce NOx emissions, was studied. The quality and distribution of flow entering the SCR plays an important role in the efficiency of the systems. A CFD study was completed initially investigating the impact on solution accuracy of different modeling approaches with respect to pressure drop and flow uniformity entering SCRs. Next, multi-species simulations were completed to analyze different modeling approaches impact on ammonia distribution and flow rates through SCRs. RANS, URANS, and DES simulations were compared in both stages. An in depth analysis of the current methodology utilized at Scania to investigate pressure drop and velocity uniformity index concluded that there is minimal benefit in changing the current methodology. DDES and URANS simulations yielded results containing less than 2% difference when compared with the current methodology. Expanding the investigation to include ammonia mixing yielded interesting disparities between simulation methods with respect to multispecies flow characteristics. This difference was attributed to disparities between the initial mixing of ammonia within the domain. The RANS and URANS simulations contained a much larger dispersion of ammonia, accredited to an increased false diffusion. DDES simulations are very computationally costly but by following time reducing processes, DDES simulations could be used early in the design and analysis phase of exhaust after treatment systems to analyze ammonia distribution and mixing.
9

Water blow out phenomena inside a heavy truck silencer / Vatten blåser ut fenomen i en tung ljuddämpare

Suram Venkata Subramaniyam, Rohit January 2020 (has links)
NOx sensors have become salient components in the development of efficient exhaust after treatment system for heavy duty vehicles in the past few years. When the accumulated water inside the silencer splashes on to the NOx sensor, it can cause permanent cracks in the sensor. To protect the sensor from this mode of failure, a dew point strategy is developed at Scania. This is important to predict when it is safe to switch on the NOx sensor without causing any harm to it. But the strategy currently includes only the phase transfer phenomena and neglects the effect of the water blow out phenomena inside the silencer. To investigate the effect of water blow out, an experimental test method is designed and the experiments are conducted at different locations in the silencer. The results from the experiments shows that the effect of water blow out is certainly an important factor to develop a better dew point strategy model. For a selected location, the quantity of water remaining after blow out and the time taken for the blow out phase are collected as data from the experiments. A mathematical model for the water blow out phenomena is developed in MATLAB. The model estimates the maximum amount of water which could be present in all the subvolumes of the silencer considering the effect of water blow out. The model is verified with the experimental data for a Scania CAS1 silencer. Calibration guidelines for the developed blow out model are also documented in this report. / NOx sensorer har blivit viktiga komponenter i utvecklingen av ett effektivt avgassystem för tunga fordon under de senaste åren. När det ackumulerade vattnet i ljuddämparen stänker på NOx-sensorn kan det orsaka permanenta sprickor i sensorn. För att skydda sensorn från detta misslyckande utvecklas en daggpunktsstrategi på Scania. Detta är viktigt att förutsäga när det är säkert att slå på NOx-sensorn utan att skada den. Men strategin innehåller för närvarande endast fasöverföringsfenomenen och försummar effekten av att vatten blåser ut fenomen inuti ljuddämparen. För att undersöka effekten av utblåsning av vatten utformas en experimentell testmetod och experimenten utförs på olika platser i ljuddämparen. Resultaten från experimenten visar att effekten av vattenblåsning verkligen är en viktig faktor för att utveckla en bättre daggpunktsstrategimodell. För en vald plats samlas mängden vatten kvar efter utblåsning och den tid det tar för utblåsningsfasen som data från experimenten. En matematisk modell för fenomen för vattenblåsning utvecklas i MATLAB. Modellen uppskattar den maximala mängden vatten som kan finnas i ljuddämparens undervolymer med tanke på effekten av vatten som blåser ut. Modellen verifieras med experimentdata för en Scania CAS1 ljuddämpare. Kalibreringsriktlinjer för den utvecklade utblåsningsmodellen dokumenteras också i denna rapport.
10

Acoustic modelling and testing of advanced exhaust system components for automotive engines

Allam, Sabry January 2004 (has links)
The increased use of the diesel engine in the passenger car, truck and bus market is due to high efficiency and lower fuel costs. This growing market share has brought with it several environmental issues for instance soot particle emission. Different technologies to remove the soot have been developed and are normally based on some kind of soot trap. In particular for automobiles the use of diesel particulate traps or filters (DPF:s) based on ceramic monolithic honeycombs are becoming a standard. This new exhaust system component will affect the acoustics and also work as a muffler. To properly design exhaust systems acoustic models for diesel particulate traps are needed. The first part of this thesis considers the modelling of sound transmission and attenuation for traps that consist of narrow channels separated by porous walls. This work has resulted in two new models an approximate 1-D model and a more complete model based on the governing equations for a visco-thermal fluid. Both models are expressed as acoustic 2-ports which makes them suitable for implementation in acoustic software for exhaust systems analysis. The models have been validated by experiments on clean filters at room temperature with flow and the agreement is good. In addition the developed filter models have been used to set up a model for a complete After Treatment Device (ATD) for a passenger car. The unit consisted of a chamber which contained both a diesel trap and a Catalytic Converter (CC). This complete model was also validated by experiments at room temperature. The second part of the thesis focuses on experimental techniques for plane wave decomposition in ducts with flow. Measurements in ducts with flow are difficult since flow noise (turbulence) can strongly influence the data. The difficulties are also evident from the lack of good published in-duct measurement data, e.g., muffler transmission loss data, for Mach-numbers above 0.1-0.2. The first paper in this part of the thesis investigates the effect of different microphone mountings and signal processing techniques for suppressing flow noise. The second paper investigates in particular flow noise suppression techniques in connection with the measurement of acoustic 2-ports. Finally, the third paper suggests a general wave decomposition procedure using microphone arrays and over-determination. This procedure can be used to determine the full plane wave data, e.g., the wave amplitudes and complex wave numbers k+ and k-. The new procedure has been applied to accurately measure the sound radiation from an unflanged pipe with flow. This problem is of interest for correctly determining the radiated power from an engine exhaust outlet. The measured data for the reflection coefficient and end correction have been compared with the theory of Munt [33] and the agreement is excellent. The measurements also produced data for the damping value (imaginary part of the wavenumber) which were compared to a model suggested by Howe [13]. The agreement is good for a normalized boundary layer thickness less than 30-40

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