Sound transmission devices have advanced filtering abilities that theoretically protect the ear from harmful Masking noise while amplifying the sounds that need to be heard, such as backup alarms. Therefore, such devices should provide improved signal detection in noise when compared to their passive counterparts. The masked threshold of a vehicular backup alarm was determined for audiometrically normal and non-normal hearers using two types of sound transmission devices and their passive counterparts within pink noise and milling machine noise at intensities of 75, 85, 95 and 105 dBA. Results indicated that the sound transmission devices did not have any statistically significant advantages over the passive devices with respect to masked threshold of a backup alarm. Therefore, it cannot be concluded that these devices offer advantage over similar passive devices with respect to signal detection. Additionally, ratings of comfort and the ability to detect the alarm for each device were gathered. Both scales did not show any significant differences between the two device types. / Master of Science

LHCb is a high-precision experiment for the study of CP violation and rare decays in B physics. It has two Ring Imaging Cherenkov (RICH) counters for particle identification. The RICH system uses Hybrid Photon Detectors (HPD) for single photon detection. This thesis describes tests performed on individual HPDs for quantum efficiency and vacuum quality. It then presents work done monitoring HPD vacuum quality through regular ion feedback measurements after they were mounted into the RICH. Also discussed is HPD vacuum degradation and how replacement and repair of deteriorated HPDs was implemented using data from the vacuum monitoring. Preparations for an upgrade to LHCb have started. The upgrade will extend the discovery potential of the LHCb by increasing the rate of data collection. This thesis presents particle identification and avour tagging studies using upgrade simulations. Flavour tagging using kaons was then reoptimised for upgrade conditions and this work is described with discussions of the results.

Currently in the United States, Active Noise Reduction (ANR) headphones cannot be tested and labeled as hearing protection devices (HPDs) due to inherent limitations with the existing psychophysical headphone testing standard, real-ear attenuation at threshold (REAT). This research focused on the use of a standard, for physical, microphone-in-real-ear testing, (MIRE, ANSI S12.42-1995), to determine if MIRE may be appropriately used to measure the total attenuation (i.e., passive + active) of ANR headphones. The REAT " Method B, Subject-Fit protocol," ANSI S12.6-1997(R2002), was also used to assess passive attenuation (and used for comparison with the MIRE data), as this is the current standard for passive Headphone attenuation testing. The MIRE protocol currently does not specify a standardized location for measurement microphone placement. Prior research is mixed as to the potential benefits and shortcomings of placing the measurement microphone outside versus inside the ear canal. This study captured and compared acoustic spectral data at three different microphone locations: in concha, in ear canal-shallow depth, and in ear canal-deep depth (with a probe tube microphone positioned near the tympanic membrane), using human test participants and five ANR headphones of differing design. Results indicate that the MIRE protocol may be used to supplant the REAT protocol for the measurement of passive attenuation, although differences were observed at the lowest-tested frequency of 125 Hz. Microphone placement analysis revealed no significant difference among the three locations specified, with a noted caveat for the probe tube microphone location at the highest tested frequency of 8000 Hz. Overall findings may be useful to standards-making committees for evaluating a viable solution and standardized method for testing and labeling ANR headphones for use as hearing protection devices. Microphone placement results may assist the practitioner in determining where to place measurement microphones to best suit their particular needs when using MIRE. Discussion includes an in-depth interpretation of the data, comparisons within and between each protocol, and recommendations for further avenues to explore based on the data presented. / Ph. D.

<p>This thesis is based on work done in two different experimental projects. </p><p>The first project, the Tau RICH, is a previously proposed τ-neutrino appearance experiment for the CERN neutrino beam at the Gran Sasso laboratory in Italy. The proposed experimental concept is based on the use of focusing RICH detectors with liquid radiator (C₆F₁₄). Simulations made with a Geant4 code show that in the proposed experimental set-up, Cherenkov light from delta electrons will constitute a severe background that in practice would render the experiment unfeasible.</p><p>The second project, ATLAS, is a general purpose detector at the CERN 14 TeV proton-proton collider LHC which will start operation in 2007. To make the reconstruction and selection of the events in ATLAS more accurate, complete and up-to-date information on the interaction of the produced particles with the detector is needed. A service program code, the Material Integration Service (MIS), has been developed which makes use of the detector descriptions already available in a Geant4 code and which uses a novel algorithm, based on line integrals evaluated within small volume elements that build up the detector. This code is demonstrated to constitute a practically useful tool of satisfactory performance and accuracy.</p><p>The charged Higgs boson production in the gluon-bottom quark mode, gb → tH^±, followed by charged Higgs decays into a chargino and a neutralino, is studied for a specific choice of values for the Minimal Supersymmetric Standard Model (MSSM) parameters. It is shown, using a Monte Carlo code to simulate the ATLAS detector and the assumed MSSM physics model, that for an integrated luminosity of 300 fb^-1, in the intermediate region 4 < tanβ < 10 where H^± decays to SM particles cannot be used for H^± discovery, charged Higgs decays to non-SM particles can be used for Higgs discovery at the 5 σ significance level.</p>

This thesis is based on work done in two different experimental projects. The first project, the Tau RICH, is a previously proposed τ-neutrino appearance experiment for the CERN neutrino beam at the Gran Sasso laboratory in Italy. The proposed experimental concept is based on the use of focusing RICH detectors with liquid radiator (C6F14). Simulations made with a Geant4 code show that in the proposed experimental set-up, Cherenkov light from delta electrons will constitute a severe background that in practice would render the experiment unfeasible. The second project, ATLAS, is a general purpose detector at the CERN 14 TeV proton-proton collider LHC which will start operation in 2007. To make the reconstruction and selection of the events in ATLAS more accurate, complete and up-to-date information on the interaction of the produced particles with the detector is needed. A service program code, the Material Integration Service (MIS), has been developed which makes use of the detector descriptions already available in a Geant4 code and which uses a novel algorithm, based on line integrals evaluated within small volume elements that build up the detector. This code is demonstrated to constitute a practically useful tool of satisfactory performance and accuracy. The charged Higgs boson production in the gluon-bottom quark mode, gb → tH±, followed by charged Higgs decays into a chargino and a neutralino, is studied for a specific choice of values for the Minimal Supersymmetric Standard Model (MSSM) parameters. It is shown, using a Monte Carlo code to simulate the ATLAS detector and the assumed MSSM physics model, that for an integrated luminosity of 300 fb-1, in the intermediate region 4 &lt; tanβ &lt; 10 where H± decays to SM particles cannot be used for H± discovery, charged Higgs decays to non-SM particles can be used for Higgs discovery at the 5 σ significance level.

<p>  </p> <p>Noise-induced hearing loss (NIHL) is a significant occupational health concern in the construction industry, necessitating effective hearing protection for workers. This project explores the detrimental consequences of environmental pollutants, specifically noise pollution common in construction settings. The research incorporates user interviews with construction workers and managers to identify challenges and motivations surrounding the use of hearing protection devices.</p> <p>My findings underscore the necessity of addressing pollution in the construction industry to safeguard the well-being of workers. Noise pollution emerges as a primary concern, leading to hearing loss, stress, decreased productivity, and safety hazards. The research revealed that workers grapple with obstacles, including discomfort, lack of awareness, and cost barriers, while also recognizing driving forces, including fear of hearing loss and the encouragement of supervisors. The design process involved thorough research, including a literature review, competitive analysis, and semi-structured user interviews, resulting in an advanced hearing protection device that prioritizes effective communication, cleanliness, and user comfort. The final product incorporates innovative features such as lighting indicators, a compact charging case, strategically positioned buttons, secure fit with magnets, and a range of color options. Furthermore, the accompanying application features customizable ambient sounds, performance feedback, and gamification elements.</p>

La réaction de désaromatisation hydroxylante de phénols (HPD) est un outil puissant pour accéder de façon biomimétique, en une seule étape à partir de 2-alkylphénols, aux ortho-quinols, c’est-à-dire les 6-alkyl-6-hydroxycyclohexa-2,4-diénones. Ces synthons peuvent être présentés tels quels par de nombreux produits naturels mais peuvent aussi servir d’intermédiaires hautement fonctionnalisés pour la construction rapide d’architectures structurales complexes. L’acide o-iodoxybenzoïque (IBX), un réactif de type iodane-?5, et sa formulation stabilisée non-explosible (SIBX) se sont révélés particulièrement efficaces pour promouvoir des réactions HPD de manière ortho-sélective. Ces travaux de thèse concernent l’application de cette réaction à l’élaboration d’un intermédiaire ortho-quinolique clé hautement fonctionnalisé pour la synthèse d’un antibiotique de type angucycline, la (+)-aquayamycine, ainsi qu’à la première synthèse totale d’un ortho-quinol naturel non dimérisant, la (+)-wasabidiénone B1. Enfin, le développement d’une version asymétrique de cette réaction a été entrepris. La génération in situ de iodanes à partir de iodoarènes chiraux et de m-CPBA comme co-oxydant permet de préparer soit des ortho-quinols de façon non racémique lorsque des quantités stoechiométriques des deux réactifs sont utilisées, soit des ortho-quinols régio- et diastéréosélectivement époxydés lorsqu’une quantité catalytique de iodoarène chiral est employée. Un suivi de ces réactions par spectrométrie de masse a conduit à la détection d’espèces de type iodanyl-?3 et/ou -?5, et à la proposition d’un mécanisme pour ces réactions de désaromatisation hydroxylante asymétrique. / The hydroxylative phenol dearomatization (HPD) reaction is a powerful tool to access, in one biomimetic step from various 2-alkylphenols, ortho-quinols, i.e., 6-alkyl-6-hydroxycyclohexa-2,4-dienones. These dearomatized moieties can be found as such in few natural products or can be used as highly functionalized intermediates. The ?5-iodane 2-iodoxybenzoic acid (IBX) and its stabilized nonexplosive formulation (SIBX) have proved particularly useful and efficient in mediating HPD reactions in a strictly ortho-selective manner. This PhD work describes the application of our SIBX-mediated HPD reaction to the elaboration of a key ortho-quinolic advanced intermediate for the synthesis of the angucycline-type antibiotic (+)-aquayamycin, and to the first total synthesis of the natural non-dimerizing ortho-quinol (+)-wasabidienone B1. An asymmetric version of this HPD reaction has been also developed. In situ generation of iodanes from chiral iodoarenes and m-CPBA as co-oxidant enables the preparation of either ortho-quinols in a non racemic form when using stoechiometric amounts of both reagents, or regio- and diastereoselectively epoxidized ortho-quinols when a catalytic amount of the chiral iodoarene is used. Monitoring of these reactions by mass spectrometry allowed the detection of ?3- and/or ?5-iodanyl-type species, and the proposition of a mechanism for these asymmetric hydroxylative dearomatization reactions.

This study focused on designing a training programme for audiometricians, using the principles of instructional design. Instructional design is the continuing, systematic development of instructional specifications, utilizing researched strategies and principles to create detailed outcomes for the development, implementation, evaluation and maintenance of training programmes. An audiometrician is defined by SANS (10083:2004), as a person registered with the Health Professions Council of South Africa as an audiometrician, hearing aid acoustician or someone trained in audiometry. Audiometricians are adult learners. Therefore, in addition to instructional design principles, the principles of adult learning were also incorporated in the training programme. The successful training of audiometricians may ensure that noise induced hearing loss is significantly reduced when audiometric monitoring is appropriately implemented as part of a hearing conservation programme. Training for audiometricians is critical in this process as incorrect audiometric monitoring may negatively influence the outcomes of a hearing conservation programme. This study followed a descriptive research design where the results were described in a quantitative manner. Data was collected by means of electronically mailed questionnaires. All participants were practicing audiometricians at the time of the study and were registered with the South African Society for Occupational Health Nursing. All participants had an audiometric certificate as qualification. For the analysis of data, 181 completed questionnaires were used. The results were analyzed and described in terms of the respondents’ own experience regarding audiometry; their opinions regarding the topics they have been taught in audiometry; the duration of their own training programmes and their opinions regarding a future training programme for audiometricians. Based on the results of the above analysis, the instructional design programme for audiometricians was developed. The obtained results were used to determine what the topics, content, duration, learning outcomes and learner evaluation methods should be in the development of a training programme for audiometricians. This research study developed a training programme for audiometricians in order to ensure that all future audiometricians have the necessary knowledge to perform comprehensive hearing evaluations, interpret audiometric findings and thereby assist in reducing noise induced hearing loss in the industrial sector through hearing conservation programmes. AFRIKAANS : Hierdie studie is toegespits op die ontwerp van ‘n onderrigprogram vir oudiometriste waarin die beginsels van onderrigontwerp toegepas is. Onderrigontwerp behels die deurlopende en stelselmatige ontwikkeling van onderrigspesifikasies deur gebruik te maak van nagevorsde strategieë en beginsels om gedetailleerde uitkomste vir die ontwikkeing, evaluering en onderhoud van opleidingsprogramme daar te stel. ‘n Oudiometris word gedefinieer deur wetgewing (SANS 10083:2004) as ‘n person wat geregistreer is by die Health Professions Council of South Africa as ‘n oudiometris, gehoorapparaat akoestikus of iemand wat opgelei is in oudiometrie. Oudiometriste is volwasse leerders. Om hierdie rede is nie net die beginsels van onderrigontwerp nie, maar ook die beginsels van volwasse leer in die onderrigprogram geïnkorporeer. Suksesvolle onderrig van oudiometriste kan verseker dat die voorkoms van geraas-geïnduseerde gehoorverlies verminder, mits oudiometriese monitering toepaslik as deel van ‘n program vir gehoorkonservering geïntegreer word. Opleiding vir oudiometriste is krities belangrik in hierdie proses want indien oudiometriese monitering verkeerd gedoen word, kan dit die gehoorkonserveringsprogram in totaliteit negatief beïnvloed. ‘n Beskrywende navorsingsontwerp is in hierdie studie gebruik en die resultate is kwantitatief beskryf. Data is deur middel van vraelyste wat elektronies versend is, versamel. Al die deelnemers was ten tye van die studie praktiserende oudiometriste wat by die South African Society for Occupational Health Nursing geregistreer was. Elkeen was in besit van ‘n oudiometriese sertifikaat as kwalfikasie. Vir data-ontleding is 181 voltooide vraelyste gebruik. Die data was geanaliseer en beskryf in terme van die respondente se eie ervaring ten opsigte van oudiometrie; hul mening omtrent die temas wat by hul opleiding ingesluit was; die duur van hul opleidingsprogramme en hul idees omtrent ‘n toekomstige opleidingsprogram vir oudiometriste. Die onderrigontwerp-program is op grond van die resultate van bognoemde analise ontwikkel. Die resultate wat verkry is, is gebruik om die temas, inhoud, duur, leeruitkomste en evalueringsmetodes in die ontwikkeling van ‘n opleidingsprogram vir oudiometriste te bepaal. Hierdie studie is gerig op die ontwikkeling van ‘n opleidingsprogram vir oudiometriste met die doel om te verseker dat hulle oor die nodige kennis beskik om omvattende gehoorevaluerings uit te voer, om oudiometriese bevindinge te interpreteer en daardeur, in gesondheidssorgprogramme, by te dra tot die vermindering van geraas-geïnduseerde gehoorverlies in die industriële sektor Copyright / Dissertation (MCommunication Pathology)--University of Pretoria, 2012. / Speech-Language Pathology and Audiology / unrestricted

The aim of my thesis on the topic „Regional and structural EU policy – economic and legislative aspect“ is a description of all important aspects of Regional policy EU and the performance of regional policy in the context of a specific project.