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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

Conscripts to their age : African National Congress operational strategy, 1976-1986

Barrell, Howard January 1993 (has links)
No description available.
2

The assassins' web : South Africa's counter-revolutionary strategy, securocracy and operations (with particular reference to the special tasking of security force units) 1978-1990

O'Brien, Kevin A. January 2000 (has links)
No description available.
3

Umyalezo olukuhlayo ekuvuseleleni i-Afrika

Martins, Luvuyo Shaun, New Partnership for Africa's Development 12 1900 (has links)
Thesis (MA)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: This study is about the persuasive message towards the Millennium African Recovery Plan, which is known today as New Partnership for African Development. It is divided into five chapters. The first chapter, which constitutes the introductory chapter, deals with the general introduction to the entire study, the scope of the study, statement of the aim and objectives of this study, also looks at the research methods. The second chapter provides a brief theoretical background to the study of persuasion, and the third chapter looks at various applications of persuasion. This forms the basis upon which the entire study will rest as it provides different theories pertaining to persuasion. The fourth chapter concentrates on a critical evaluation of persuasion messages. The messages, which are analysed in this study, are selected from the newsletter ANC Today. These 4 articles are: 1. Africa's people central to success of recovery plan. Vol. 1 no. 2, 2-8 February 2001. 2. One step to the birth of the African Union. Vol. 1 no. 7, 9-15 March 2001. 3. Important steps to deepen democratic practice in Southern Africa. Vol. 1 no. 16, 11- 17 May 2001. 4. Our commitment to Africa Vol. 1 no. 18,25-31 May 2001 The fifth chapter contains general conclusions drawn from the persuasive messages in chapter 4. Translations for terminology are provided and are contained in the appendix, which is found at the end of this study, which is followed by the bibliography. / AFRIKAANSE OPSOMMING: Hierdie studie handeloor die oorredende boodskap gerig op die Millenium Afrika Hernuwingsplan, ook bekend as die 'Nuwe vennootskap vir Afrika se ontwikkeling'. Die studie is verdeel in vyf hoofstukke. Die eerste hoofstuk, wat die inleidende hoofstuk is, bied 'n algemene inleiding tot die studie as geheel, gee 'n oorsig van die omvang van die studie, bied die doelstellings van die studie, en gee 'n uiteensetting van die navorsingsmetode. Die tweede hoofstuk bied 'n kort teoretiese agtergrond tot die studie van oorreding, en die derde hoofstuk handeloor 'n verskeidenheid toepassings van oorreding. Hierdie hoofstuk vorm die basis waarop die navorsing berus aangesien dit 'n oorsig bied oor verskillende teorieë van oorreding. Die vierde hoofstuk konsentreer op 'n kritiese evaluering van oorredingsboodskappe. Die boodskappe wat analiseer word in hierdie studie is geselekteer uit die nuusbrief ANC Today. Die vier artikels is die volgende: 1. Africa's people central to success of recovery plan. Vol. 1 no. 2, 2-8 February 2001. 2. One step to the birth of the African Union. Vol. 1 no. 7, 9-15 March 2001. 3. Important steps to deepen democratic practice in Southern Africa. Vol. 1 no. 16, 17- 17 May 2001. 4. Our commitment to Africa. Vol. 1 no. 18,25-31 May 2001. Die vyfde hoofstuk bevat algemene gevolgtrekkings met betrekking tot die oorredende boodskappe wat ontleed is in hoofstuk 4. Vertalings van terminologie word in die bylae aan die einde van die studie gegee. / ISIXHOSA SISHWANKATHELO: Esi sifundo simalunga nomyalezo olukuhlayo ekuvuselelweni kwe-Afrika. Sahlulwe saba ziza hluko ezintlanu. Isahluko sokuqala, esiphawula intshayelelo yesahluko, sijongana nentshayelelo eqhelekileyo kuso sonke isifundo, umda wesifundo, ingxelo yenjongo yesi sifundo, kwaye sijonga kwizicwangciso zophando. Isahluko sesibini sinika imvelaphi yethiyori kwisifundo solukuhlo., kwaye isahluko sesithathu sijonga kwiindlela zokusetyenziswa kolukuhlo. Oku kwenza isakhelo apho sonke esi sifundo siza kuqwalasela khona njengokuba sinika iithiyori ezahlukeneyo malunga nolukuhlo. Isahluko sesine sizikis'ingqondo kuvavanyo olunzima Iwemiyalezo yolukuhlo. Imiyalezo, eboniswayo apha kwesi sahluko, ikhethwe kumaphetshana e-"ANC Today". La maphetshana mane ngala: 1. Africa's people central to success of recovery plan. Vol. 1 no. 2, 2-8 February 2001. 2. One step to the birth of the African Union. Vol. 1 no.7, 9-15 March 2001. 3. Impotant steps to deepen democratic practice in Southern Africa, Vol. 1 no. 16, 11- 17 May 2001. 4. Our commitment to Africa. Vol.t no.18, 25-31 May 2001. Isahluko sesihlanu siqulathe iziqukumbelo eziqelekileyo ezisukela kwimiyalezo yolukuhlo kwisahluko se-4. Isigama esitolikiweyo sinikiwe kwaye siqulathwe kwi-apendiksi, efumaneka ekupheleni kwesi sifundo, elandelwa yi-bibliyografi.
4

La imagen social de la profesión de enfermería a través de la prensa escrita - Chimbote - Perú

Morán Silva, Rosa María January 2017 (has links)
La imagen social de una profesión en gran medida es construida por la forma en que es expuesta y divulgada por los medios de comunicación ante la sociedad, mostrando la coyuntura del ejercicio profesional, así como, artículos estereotipados, distorsionados y poco acertados a la realidad. Por todo ello, surge la presente investigación cualitativa, la cual tuvo por objetivo caracterizar, analizar y discutir los elementos que determinan la construcción de la imagen social de la profesión en enfermería, a través de la prensa escrita, en la ciudad de Chimbote-Perú. Tiene como marco referencial y metodológico la teoría de la representación social según Serge Moscovici (1961) y Denize Jodelet (2003), desde la perspectiva procesual. Se analizaron treinta artículos de tres periódicos de mayor circulación del ámbito nacional, regional y local (el comercio, el trome y El diario de Chimbote). Se asumió como instrumentos una guía de examen de periódico y una guía iconográfica. El tratamiento de los datos se realizó a través del análisis documental e iconográfico, considerando dos grandes categorías: transformación histórico-social de la imagen de la profesión de enfermería; y (Re) surgimiento de una imagen socio-política y laboral de la Enfermería. De acuerdo a lo analizado, se evidencia que la representación social de la profesión de enfermería se construye a partir del dinamismo e interacción de los grupos editoriales y columnistas, de acuerdo a la representación que ellos tienen de la realidad sanitaria y de los mismos profesionales de enfermería. Esta representación está fuertemente cargada a un contexto de imagen tradicional y hegemónica del sector. / Tesis
5

On Implemintation of Loudspeakers for Feedback Control, Open-Air, Active Noise Control Headsets

White, Andrew 11 April 1999 (has links)
The loudspeakers used in active noise reduction (ANR) headsets are generally identical to loudspeakers used in commercial headphones. Unfortunately, the frequency response characteristics of these loudspeakers are not particularly well suited for open-air active noise control (ANC). Open-air headsets float outside the ear with no contact between the system and the user and allow for regular conversation with others in the environment. This study has identified three limitations on the closed-loop performance of open-air headsets: the distribution of gain and phase in the loudspeaker's open-loop frequency response function, manufacturing variations in loudspeakers that can deviate from design specifications by up to 40%, and the variations in acoustic impedance coupling (ear-to-speaker) among users. This thesis explores the mechanisms that underlie these limitations with the goal of designing open-air headsets that are robust to manufacturing and user variations. Methods are introduced on ways to minimize the effects of manufacturing and user variations and are proven by experiment. With these variations minimized, the controller's design is only limited by the frequency response of the loudspeaker. A comprehensive examination of techniques to model moving-coil loudspeakers is presented followed by detailed studies on how each parameter affects the system's frequency response. A review of frequency domain control system design is then included to help the reader understand loop-shaping techniques. Finally, a compensator is designed for an open-air ANR headset using loop-shaping techniques and the robustness of the closed-loop performance is verified experimentally. / Master of Science
6

An Investigation of Performance Limitations in Active Noise Reduction Headsets

Clatterbuck, Daniel C. 13 May 1998 (has links)
Closed-loop performance of an active noise reduction (ANR) headset is limited by phase lag. Speaker dynamics, control hardware, and acoustic wave propagation from the control speaker to the error microphone all contribute to this phase lag. Understanding these sources of phase lag and their relative effects on performance allows for better design of an analog or digital ANR headset. This thesis demonstrates that the three most significant sources of phase lag in a digital ANR headset are the dynamics of the control speaker's diaphragm, the anti-aliasing filter, and the smoothing filter. Additionally, it is demonstrated that the acoustic wave propagation from the control speaker to the error microphone is not a major contributor of phase lag. Based on these results, it was determined that attention should be focused on the anti-aliasing and smoothing filters when attempting to minimize phase lag and improve a digital ANR system's performance. A design procedure was developed to calculate filter responses that contributed a minimal amount of phase lag to a headset. Using this minimal phase filter design procedure, a digital ANR headset was successfully built and tested. Initial testing revealed that the anti-aliasing filter was not as vital to performance as the smoothing filter. Further testing indicated that the anti-aliasing requirements could be effectively met through the use of only a smoothing filter. Therefore, in order to minimize the phase lag of a digital ANR headset, a smoothing filter may be utilized in the absence of an anti-aliasing filter for some applications. / Master of Science
7

Fator S astrofisico para a reação de captura 4He(t,g)7Li pela investigação da reação de transferência elástica no sistema 7Li + 4He / Astrophysical S factor for the 4He(t,g)7Li capture reaction by the investigation of the elastic-transfer reaction in the 7Li + 4He system

Denke, Robson Zacarelli 10 April 2007 (has links)
Neste trabalho obtivemos o coeficiente de normalização da parte não ressonante da reação de captura 3H(alpha,gama)7Li (ou alternativamente, o fator S astrofísico) aplicando o método indireto ANC (Coeficientes de Normalização Assintótica) para a reação de transferência elástica do sistema 7Li + 4He. Essa reação de captura é de suma relevância na nucleosíntese de elementos leves no Universo primordial. Nesse método, o fator espectroscópico (ou alternativamente, o ANC) é obtido pela investigação de uma reação de transferência periférica que contenha como vértice a correspondente reação de captura. Reações de transferência têm normalmente dois vértices e um deles deve ser conhecido para que possamos obter o outro. No caso de uma transferência elástica, cuja característica é que o canal de saída elástico e de transferência são os mesmos, existe a vantagem da necessidade de consideração de apenas um vértice. Assim, uma análise combinada da distribuição angular para o espalhamento elástico 4He(7Li,7Li)4He, e para a reação de transferência 4He(7Li,4He)7Li, permitiu a extração do fator espectroscópico e consequentemente do ANC para o estado ligado <3He|4He>=7Li de uma forma única. As distribuições angulares para esses processos foram medidas no Laboratório Pelletron de São Paulo em duas energias de centro de massa 9.67 MeV e 10.62 MeV. Utilizamos nessas medidas feixes de 7Li obtidos no acelerador Pelletron com as energias de laboratório de 26.6 e 29.2 MeV. Empregamos um alvo gasoso de 4He e um sistema de colimadores de dupla-fenda na detecção. As partículas de 7Li espalhadas elasticamente e as partículas alfa da reação de transferência foram ambas detectadas em ângulos de laboratório diânteiros por um sistema de telescópios delta E - E com detectores de silício. Um código de simulação de Monte Carlo foi desenvolvido para calcular o ângulo sólido para esse sistema de fendas em ângulos próximos de zero grau. Um conjunto de parâmetros globais do Modelo Óptico foi obtido da análise das distribuições angulares do espalhamento elástico do sistema 7Li + 4He, juntamente com outras distribuições angulares obtidas da literatura em diferentes energias (~ 7-32 MeV). Os parâmetros do potencial óptico encontrados foram usados em uma análise de DWBA (Aproximação de Born de Ondas Distorcidas) para descrever a contribuição da reação de transferência de um tritio nas distribuições angulares. O fator espectroscópico obtido para o sistema ligado <3He|4He>=7Li foi S = 0.55+-0.03 e o coeficiente ANC C2 = 17.5 +- 1.0 fm-1. Com estes resultados, a seção de choque de captura para a reação 3H(alpha,gama)7Li e o respectivo fator S astrofísico foram calculados. / The normalization coefficient for the non-resonant part of the 3H(alpha,gama)7Li capture reaction (or alternately, the astrophysical S-factor) was obtained with the indirect method ANC (Asymptotic Normalization Coefficients). In this method the spectroscopic factor (or alternately, the ANC) is extracted from the investigation of a peripheral transfer reaction, which involves the same vertex as the corresponding capture reaction. Usually transfer reactions have two vertexes and the spectroscopic factor for one of them has to be known to obtain the other. In this work we investigate the 4He(7Li,4He)7Li elastic transfer reaction to obtain the spectroscopic factor and ANC for the 4He + t = 7Li bound system. The elastic transfer process, where the elastic and transfer exit channels are the same, has the advantage of having only one unknown vertex. Thus, the combined analysisof the angular distribution for elastic 4He(7Li,7Li)4He, and transfer process 4He(7Li,4He)7Li, allowed the extraction of the spectroscopic factor (and ANC) for the <3H|4He>=7Li bound system in an unique way. Angular distributions for these processes were measured at the Pelletron Laboratory at the center of mass energies of 9.67 MeV and 10.62 MeV. In these measurements, the 7Li beams with 26.6 MeV and 29.2 MeV were obtained from the Sao Paulo Pelletron accelerator. A 4He gas target and a double-slit collimator system were used. The 7Li scattered particles and alpha particles from transfer reaction were both detected at forward angles by a set of delta E - E silicon detectors telescopes. A Monte Carlo simulation code was developed to calculate the solid angle for the collimator system near the zero degree. A global optical potential parameters set for the 7Li + 4He system were defined using the measured elastic scattering angular distribution and other angular distributions obtained from the literature at different energies (from ~ 7-32 MeV). These optical potential parameters were used in the DWBA (Distorted Wave Born Approximation) analysis to describe the tritium transfer reaction contribution in the angular distributions. The obtained spectroscopic factor for the <3H,4He>=7Li bound system is S = 0.55+-0.03 and the ANC coefficient C2 = 17.5+-1.0 fm-1. With these results, the 3H(alpha,gama)7Li direct capture cross sections and astrophysical S-factor were calculated.
8

Fator S astrofisico para a reação de captura 4He(t,g)7Li pela investigação da reação de transferência elástica no sistema 7Li + 4He / Astrophysical S factor for the 4He(t,g)7Li capture reaction by the investigation of the elastic-transfer reaction in the 7Li + 4He system

Robson Zacarelli Denke 10 April 2007 (has links)
Neste trabalho obtivemos o coeficiente de normalização da parte não ressonante da reação de captura 3H(alpha,gama)7Li (ou alternativamente, o fator S astrofísico) aplicando o método indireto ANC (Coeficientes de Normalização Assintótica) para a reação de transferência elástica do sistema 7Li + 4He. Essa reação de captura é de suma relevância na nucleosíntese de elementos leves no Universo primordial. Nesse método, o fator espectroscópico (ou alternativamente, o ANC) é obtido pela investigação de uma reação de transferência periférica que contenha como vértice a correspondente reação de captura. Reações de transferência têm normalmente dois vértices e um deles deve ser conhecido para que possamos obter o outro. No caso de uma transferência elástica, cuja característica é que o canal de saída elástico e de transferência são os mesmos, existe a vantagem da necessidade de consideração de apenas um vértice. Assim, uma análise combinada da distribuição angular para o espalhamento elástico 4He(7Li,7Li)4He, e para a reação de transferência 4He(7Li,4He)7Li, permitiu a extração do fator espectroscópico e consequentemente do ANC para o estado ligado <3He|4He>=7Li de uma forma única. As distribuições angulares para esses processos foram medidas no Laboratório Pelletron de São Paulo em duas energias de centro de massa 9.67 MeV e 10.62 MeV. Utilizamos nessas medidas feixes de 7Li obtidos no acelerador Pelletron com as energias de laboratório de 26.6 e 29.2 MeV. Empregamos um alvo gasoso de 4He e um sistema de colimadores de dupla-fenda na detecção. As partículas de 7Li espalhadas elasticamente e as partículas alfa da reação de transferência foram ambas detectadas em ângulos de laboratório diânteiros por um sistema de telescópios delta E - E com detectores de silício. Um código de simulação de Monte Carlo foi desenvolvido para calcular o ângulo sólido para esse sistema de fendas em ângulos próximos de zero grau. Um conjunto de parâmetros globais do Modelo Óptico foi obtido da análise das distribuições angulares do espalhamento elástico do sistema 7Li + 4He, juntamente com outras distribuições angulares obtidas da literatura em diferentes energias (~ 7-32 MeV). Os parâmetros do potencial óptico encontrados foram usados em uma análise de DWBA (Aproximação de Born de Ondas Distorcidas) para descrever a contribuição da reação de transferência de um tritio nas distribuições angulares. O fator espectroscópico obtido para o sistema ligado <3He|4He>=7Li foi S = 0.55+-0.03 e o coeficiente ANC C2 = 17.5 +- 1.0 fm-1. Com estes resultados, a seção de choque de captura para a reação 3H(alpha,gama)7Li e o respectivo fator S astrofísico foram calculados. / The normalization coefficient for the non-resonant part of the 3H(alpha,gama)7Li capture reaction (or alternately, the astrophysical S-factor) was obtained with the indirect method ANC (Asymptotic Normalization Coefficients). In this method the spectroscopic factor (or alternately, the ANC) is extracted from the investigation of a peripheral transfer reaction, which involves the same vertex as the corresponding capture reaction. Usually transfer reactions have two vertexes and the spectroscopic factor for one of them has to be known to obtain the other. In this work we investigate the 4He(7Li,4He)7Li elastic transfer reaction to obtain the spectroscopic factor and ANC for the 4He + t = 7Li bound system. The elastic transfer process, where the elastic and transfer exit channels are the same, has the advantage of having only one unknown vertex. Thus, the combined analysisof the angular distribution for elastic 4He(7Li,7Li)4He, and transfer process 4He(7Li,4He)7Li, allowed the extraction of the spectroscopic factor (and ANC) for the <3H|4He>=7Li bound system in an unique way. Angular distributions for these processes were measured at the Pelletron Laboratory at the center of mass energies of 9.67 MeV and 10.62 MeV. In these measurements, the 7Li beams with 26.6 MeV and 29.2 MeV were obtained from the Sao Paulo Pelletron accelerator. A 4He gas target and a double-slit collimator system were used. The 7Li scattered particles and alpha particles from transfer reaction were both detected at forward angles by a set of delta E - E silicon detectors telescopes. A Monte Carlo simulation code was developed to calculate the solid angle for the collimator system near the zero degree. A global optical potential parameters set for the 7Li + 4He system were defined using the measured elastic scattering angular distribution and other angular distributions obtained from the literature at different energies (from ~ 7-32 MeV). These optical potential parameters were used in the DWBA (Distorted Wave Born Approximation) analysis to describe the tritium transfer reaction contribution in the angular distributions. The obtained spectroscopic factor for the <3H,4He>=7Li bound system is S = 0.55+-0.03 and the ANC coefficient C2 = 17.5+-1.0 fm-1. With these results, the 3H(alpha,gama)7Li direct capture cross sections and astrophysical S-factor were calculated.
9

Évaluation des fonctions de pédotransfert d’un sol hétérogène, milieu récepteur d’eau usée traitée, sur un site pilote dédié / Evaluation of pedotransfer functions of a heterogeneous soil, the receptor milieu for treated wastewater, a dedicated pilot site

Nasri, Behzad 10 December 2013 (has links)
Cette thèse a été effectuée dans le cadre du projet ANCRES. Son rôle est d'assurer la compréhension physique du milieu récepteur, le sol, alors qu'une autre équipe étudie l'impact physico-chimique des eaux usées traitées sur le sol. Pour cela, il faut connaître ses propriétés texturales et structurales contrôlant ses fonctions d'épuration et d'évacuation. La problématique est donc de comprendre le processus de l'infiltration imposée par un dispositif d'ANC dans un sol caillouteux. D'abord, suite au positionnement du site pilote d'ANC au pied d'un versant au cœur du plateau portlandien dans le département de l'Yonne en France, on a identifié là un type de sol hétérogène et complexe, caillouteux, une colluvion qui n'était pas cartographiée sur la carte géologique BRGM de cette région et sur laquelle on focalise la thèse. Ensuite, dans le sol complexe du site pilote, on a d'abord mesuré la conductivité hydraulique du sol par l'appareil Guelph sur 15 m² de la fouille de l'ANC à une profondeur de 120 cm : au total, on a fait 15 essais d'infiltration. De plus, on a récupéré 15 échantillons du sol accompagnant ses essais de Guelph pour la caractérisation physique au laboratoire. On a mesuré la texture, l'humidité résiduelle (HR), la teneur en cailloux (Rw) et la matière organique (MO) des échantillons au laboratoire. Ensuite, pour l'étude du processus d'infiltration, on a instrumenté ce site par un dispositif de surveillance hydrique (tensiométrie, teneur en eau, piézométrie) et de prélèvement d'eau interstitielle du sol. De plus, la masse volumique (densité) apparente d'un sol hétérogène a été déterminée. Parmi les paramètres mesurés, certains sont choisis comme indicateurs pour caractériser un sol comme milieu récepteur potentiel des eaux usées traitées en ANC. Puis, en utilisant la MO et la texture des échantillons, on a estimé la masse volumique apparente de la matrice du sol du site piloteau moyen de fonctions de pédotransfert appelées BD-FPTs et on a testé la relation entre la conductivité hydraulique à saturation Ks et la texture de ce sol complexe. Pour cela, une méthodologie en quatre phases a été développée pour évaluer la capacité prédictive des fonctions Ks-FPTs. Cette méthodologie de sélection n'a pas été trouvée dans la littérature mais est élaborée pour les besoins de la thèse. On a déduit les meilleures Ks-FPTs pour ce type de sol. Enfin, avec les données d'humidité volumique et du potentiel matriciel du sol, acquises par une centrale d'acquisition des données, le régime hydrodynamique du sol sous le massif filtrant de l'ANC a été étudié et on a mis en évidence l'écoulement préférentiel dans un sol caillouteux. Les résultats ont montré que dans la colluvion, bien que la matrice du sol soit fine, la conductivité hydraulique mesurée est plus élevée qu'attendu. Cela démontre que la fraction des cailloux dans le sol joue un rôle essentiel en accélérant l'évacuation des eaux usées traitées et aussi l'eau pluviale vers les couches sous-jacentes, et finalement vers la nappe. Cette propriété serait un point fort pour la fonction de transfert du sol et on peut en déduire une méthode pour améliorer la capacité de transfert de l'eau des sols lourds dans les projets d'aménagement urbain ou périurbain : l'ajout de graviers et graves calcaires par mélange au sol en place. On conclut que cette expérimentation, unique en son genre, a été utile pour évaluer la fonction de rétention / transfert de l'eau dans le sol recevant les eaux usées traitées. On a identifié les paramètres prédicteurs pertinents et les relations empiriques qui permettent de faire l'économie de nombreux essais in situ d'eau / The soil is an essential compartment in hydrologic cycle of water in the nature. Therefore, it is clear that taking into account the properties and organization of the soil is essential to the understanding and management of flows involved in the development of the quality of groundwater and surface water. The on-site sanitation (ANC) is a management method of domestic wastewater, by which the water is sent into the soil after settling and filtration liquefaction / aerobic degradation. The second step was often provided by the top soil in place himself, and this continues to this day on many plots of on-site sanitation.This thesis was carried out under ANCRES project. Its role was to ensure the physical understanding of the receptor medium, soil, while another research team was investigating the physico-chemical impact of treated wastewater on the sol. To ensure it, we have to understand its textural and structural properties controlling its purifying power and hydrodynamic processes. So, the problematic is to understand the process of infiltration imposed by an ANC in a heterogeneous stony soil. At first, due to the positioning of the pilot ANC site, at the foot of a slope in the Yonne department in France, a type of complex and heterogeneous soil, a colluvion, was identified. This soil has not been mapped on the BRGM (Bureau de recherches géologiques et minières) geological map of the area. So, the thesis was focalised on this soil. Then, in this soil complex at a depth of the 120 cm of the excavation of the ANC, the soil hydraulic conductivity was first measured by a Guelph apparatus on 15 m². We totally made 15 infiltration tests. Furthermore, we have collected 15 soil samples with each Guelph test for physics laboratory physical characterization. Then, in order to study the soil functions, this site was instrumented by the water monitoring devices (tensiometers, water content probes, and piezometer) and the interstitial water sampling device from the soil. In addition, the bulk of this heterogeneous soil was determined. Among the measured parameters, a series of indicators chosen to characterize the soil as a potential receptor medium of treated wastewater of the ANC. Then, the bulk density of the soil matrix using pedotransfer functions called BD-FPTs was estimated and the relationship between saturated hydraulic conductivity Ks and the texture of the soil complex (by Ks-FPT function) was tested. For this aim, a four-phase methodology was developed to assess the predictive ability of Ks- FPTs functions. This methodology in four phases is not found in the literature but was prepared for the purposes of the thesis. We concluded the best Ks- FPTS for this type of soil. Finally, with the volumetric water content and soil matrix potential data acquired by a the data loggers, the hydrodynamic regime of the soil under the sand pack of the ANC has been studied and demonstrated the preferential flow in a stony soil was demonstrated. The results showed that in the colluvion, although the soil matrix is fine, the measured hydraulic conductivity is higher than expected. This shows that the stone fraction in the soil plays an important role in accelerating the evacuation of treated wastewater and also rainwater to the underlying layers, and finally to the water table. This property would be a strong point for the transfer function of the soil and we can deduce a method to improve the transfer function of heavy soils in urban or peri-urban development projects. This could be possible by adding the gravel and -limestone to soil matrix and mixing them. It has been concluded that this experiment, unique in its kind, has been useful in evaluating the function of retention / transfer of water in the soil receiving treated wastewater. In addition, the relevant predictor parameters and empirical relationships that make the economy of many water tests were identified
10

An investigation into outside factors effect on ANC headphone performance

Grahn, Andreas, Lindgren, Eddie January 2022 (has links)
In the current studied literature there is a lack of data and documentation on how outside factors affect the performance of ANC headphones. The purpose of this thesis is to investigate how these factors affect ANC headphone performance. The investigation into these factors was done by gathering quantitative data with experiments. The analysis method chosen was an ANOVA-inspired method that compared the differences found in the processed data. The results show that the sample variation between the number of speakers used did not differ by much. However, the variability in the samples collected using different noise types was noticeably higher while short noise resulted in odd-shaped graphs. When combining parameters from the different tests, effects such as graph shapes, seem to remain. These are the conclusions made. When testing with pink noise, the amount of speakers used and how long the pink noise is played makes a minimal difference for attenuation and variation. However, having more speakers and playing the sound for longer durations creates slightly more stable measurements. Unstable noise recordings are unsuitable for product quality testing due to the unreliable results they give. These noise recordings are still suitable for other research purposes.

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