Rozprawy doktorskie: „Acoustical insulation”

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Nguyen, Quyet D. [Verfasser], Reimund [Akademischer Betreuer] Gerhard i Ronald [Akademischer Betreuer] Plath. "Electro-acoustical probing of space-charge and dipole-polarization profiles in polymer dielectrics for electret and electrical-insulation applications / Quyet Doan Nguyen ; Reimund Gerhard, Ronald Plath". Potsdam : Universität Potsdam, 2019. http://d-nb.info/1218405678/34.

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Nguyen, Quyet Doan [Verfasser], Reimund [Akademischer Betreuer] Gerhard i Ronald [Akademischer Betreuer] Plath. "Electro-acoustical probing of space-charge and dipole-polarization profiles in polymer dielectrics for electret and electrical-insulation applications / Quyet Doan Nguyen ; Reimund Gerhard, Ronald Plath". Potsdam : Universität Potsdam, 2019. http://d-nb.info/1218405678/34.

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Cambridge, Jason Esan. "The Sound Insulation of Cavity Walls". Thesis, University of Canterbury. Mechanical Engineering, 2012. http://hdl.handle.net/10092/7332.

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Lightweight building materials are now commonly employed in many countries in preference to heavyweight materials. This has lead to extensive research into the sound transmission loss of double leaf wall systems. These studies have shown that the wall cavity and sound absorption material placed within the cavity play a crucial role in the sound transmission through these systems. However, the influence of the wall cavity on the sound transmission loss is not fully understood. The purpose of this research is to obtain a comprehensive understanding of the role played by the wall cavity and any associated sound absorption material on the sound transmission loss through double leaf wall systems. The research was justified by the fact that some of the existing prediction models do not agree with some observed experimental trends. Gösele’s theory is expanded and used in the creation of an infinite and finite vibrating strip model in order to acquire the desired understanding. The sound transmission loss, radiated sound pressure and directivity of double leaf systems composed of gypsum boards and glass have been calculated using the developed model. A method for calculating the forced radiation efficiency has also been proposed. Predictions are compared to well established theories and to reported experimental results. This work also provides a physical explanation for the under-prediction of the sound transmission loss in London’s model; explains why Sharp’s model corresponds to Davy’s with a limiting angle of 61° and gives an explanation for Rindel’s directivity and sound transmission loss measurements through double glazed windows. The investigation also revealed that a wide variety of conclusions were obtained by different researchers concerning the role of the cavity and the properties of any associated sound absorption material on the sound transmission loss through double wall systems. Consequently recommendations about the ways in which sound transmission through cavity systems can be improved should always be qualified with regard to the specific frequency range of interest, type of sound absorption material, wall panel and stud characteristics.

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Öqvist, Rikard. "Variations in sound insulation in lightweight timber constructions". Licentiate thesis, Luleå tekniska universitet, Drift, underhåll och akustik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26446.

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This licentiate thesis deals with the topic of variations and uncertainties in building acoustic parameters for lightweight timber constructions. A higher safety margin to the legal requirements is needed to compensate for acoustical uncertainties, which leads to higher costs. Building costs can be reduced if the variations can be identified and controlled. The project was limited to industrially prefabricated timber frame based volumes and massive timber based plate elements. This thesis is based on the work reported in three papers (A, B and C). In paper A, the variations in impact and airborne sound insulation were assessed and quantified in 30 nominally identical volume built apartments in a four-storey building. Large variations were found and the underlying causes were investigated. A statistically significant difference between floor numbers was found as the highest floor achieved better sound insulation. This difference was assumed to be caused by the higher static load on lower floors affecting the elastic layer used to structurally connect the apartments. In paper B, three room volumes were followed and measured at different stages of completion throughout the construction process. The objective was to test if acoustical deviations in the field can be identified at earlier construction stages. An ISO tapping machine was used to excite the floors and the response was measured at 20 positions. The airborne and impact sound insulation were measured in the finished building. Deviations were found, but these could not be traced to earlier stages of completion. In Paper C, the variations in sound insulation of a cross-laminated timber (CLT) building system was investigated. The construction was based on prefabricated wall and floor plate elements which were mounted at the building site. A number of acoustical uncertainties related to the measurement procedure were also investigated. The measurement uncertainty was small in comparison to the total variations. The degree of prefabrication for the CLT system was lower compared to the volume system, which indicated a greater scope for poor workmanship. All papers indicate a higher sound insulation on the upper floors in a building. It is therefore important to carefully design the elastic layer between floor numbers. The measurement uncertainty has been continuously considered in this thesis. In order to properly identify and quantify variations, the measurement uncertainty should be minimised. Advantages and drawbacks with different measurement methods and directions for future research are discussed in the concluding chapters.
Godkänd; 2010; 20101110 (ricokv); LICENTIATSEMINARIUM Ämnesområde: Teknisk akustik/Engineering Acoustics Examinator: Professor Anders Ågren, Luleå tekniska universitet Diskutant: Teknologie doktor Christian Simmons, Simmons akustik & utveckling AB, Göteborg Tid: Torsdag den 16 december 2010 kl 13.00 Plats: F719 Taylor, Luleå tekniska universitet

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Forsman, Jimmy. "Game engine based auralization of airborne sound insulation". Thesis, Umeå universitet, Institutionen för fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-149498.

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Describing planned acoustic design by single number ratings yields a weak link to the subjective event, especially when the single number ratings are interpreted by others than experienced acousticians. When developing infrastructure, tools for decision making needs to address visual and aural perception. Visual perception can be addressed using game engines and this has enabled the establishment of tools for visualizations of planned constructions in virtual reality. Audio engines accounting for sound propagation in the game engine environment are steadily developing and have recently been made available. The aim of this project is to simulate airborne sound insulation by extending the support of recently developed audio engines directed towards virtual reality applications. The case studied was airborne sound insulation between two adjacent rooms in a building, the sound transmitted to the receiving room through the building structure resulting from sound pressure exciting the structural elements in the adjacent source room into vibration. The receiving room composed modelled space in the game engine Unreal Engine and Steam Audio was the considered audio engine. Sound transmission was modelled by filtering based on calculations of transmission loss via direct and flanking paths using the model included in the standard EN 12354-1. It was verified that the filtering technique for modelling sound transmission reproduced attenuations in correspondence with the predicted transmission loss. Methodology was established to quantify the quality of the audio engine room acoustics simulations. A room acoustics simulation was evaluated by comparing the reverberation time derived from simulation with theoretical predictions and the simulated reverberation time showed fair agreement with Eyring’s formula above its frequency threshold. The quality of the simulation of airborne sound insulation was evaluated relating the sound field in simulation to insulation classification by the standardized level difference. The spectrum of the simulated standardized level difference was compared with the corresponding sound transmission calculation for a modelled scenario. The simulated data displayed noticeable deviations from the transmission calculation, caused by the audio engine room acoustics simulation. However, the simulated data exhibited cancellation of favourable and unfavourable deviations from the transmission calculation resulting in a mean difference across the spectrum below the just noticeable difference of about 1 dB. Single number ratings was compared and the simulated single number rating was within the standard deviation of how the transmission model calculates predictions for a corresponding practical scenario measured in situ. Thus, the simulated data shows potential and comparisons between simulated data, established room acoustics simulation software and in situ measurements should further be made to deduce whether the deviations entails defects in the airborne sound insulation prediction or is an error imposed by the audio engine room acoustics simulation.

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Přikrylová, Pavlína. "Vývoj tepelně izolačních materiálů na bázi odpadních textilních vláken". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265439.

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The increasing quantity of waste represents serious environmental, social and economic problem. Wastes produced from industry and households. A large part of the economy transforms a certain amount of raw materials to waste in their production, because it is currently emphasis is placed on finding sustainable sources of raw materials. One of the suitable secondary raw materials can be discarded textiles or waste from the textile industry. These kinds of textile waste often ends up in landfills or incinerators, so it is from an ecological and environmentally advantageous to their further use. The diploma thesis deals with the study and development of thermal and acoustic insulation materials based on textile fibers. It focuses on the legislative requirements for waste management for the sorting of textile wastes and their subsequent modification before reuse. Further it contains kinds of textile fibers and bonding technologies thermal and acoustic insulation materials. Finally, an evaluation of thermal insulation, acoustic and mechanical properties of fibrous insulation materials.

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Shi, Wanqing. "Assessing and modelling impact sound insulation of wooden joist constructions". Licentiate thesis, Luleå tekniska universitet, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26012.

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Impact sound insulation is one of the most important aspects when assessing sound insulation of floor constructions in buildings. For assessing the impact sound insulation of aconstruction, a standard tapping machine is used as a sound source. However, the use of the current standard tapping machine has been criticised, especially with regard to measurement of wooden joist floors since the noise spectrum generated by a tapping machine differs from the spectrum generated by actual footfall. There are insufficient low frequency components in the noise spectrum produced by the tapping machine and it does not, therefore, accurately reflect low frequency noise from the construction.Reduce impact sound level from wooden joist floors are the main object of our study. It is important to be able to predict the sound insulation properties of wooden joist constructions at the design stage. To reduce the noise level in the receiving room, the input power transmitted through the construction must be estimated where the appropriate sound- and vibration-insulation can be designed.This study has investigated the waveform and frequency spectra of human footfall (walking, rum- ingand jumping); of the dropping of sand balls, sand bags and tires; and of the standard tapping machine. The impact sound power radiation from a wooden joist construction while applying different impact sources, such as actual footfall and the standard tapping machine, have also been studied.Research was also carried out regarding the development of a practical impact sound insulation calculation method for wooden joist floor constructions. The characteristics with regard to mechanical properties of floor construction was calculated using the impedance method. The impact sound level inside the sound receiving room was determined. The method developed can predict the basic performance of the wooden floor structure when excited by impact sounds.
Godkänd; 1995; 20070108 (biem)

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Bernstein, Joseph Barry. "Electrical characterization of polymeric insulation by electrically stimulated acoustic wave measurements". Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/54340.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1990.
Includes bibliographical references (leaves 207-211).
by Joseph Barry Bernstein.
Ph.D.

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Mojolla, Roberto 1971. "Fonte geradora de impacto padronizado : construção e qualificação". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257890.

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Orientador: Stelamaris Rolla Bertoli
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-27T02:02:34Z (GMT). No. of bitstreams: 1 Mojolla_Roberto_M.pdf: 4732831 bytes, checksum: e5a198764e38a4eea41b14c8e3fbcaa0 (MD5) Previous issue date: 2015
Resumo: Uma das queixas mais frequentes entre moradores de edifícios residenciais é o incomôdo causado por ruídos de impactos nos sistemas piso-teto decorrentes do caminhar ou quedas de objetos. Segundo as normas nacionais e internacionais, avaliar o desempenho acústico destes sistemas depende do uso de equipamentos normalizados e certificados. Para atender aos métodos de avaliação do desempenho acústico sugerido pelas normas, é necessário importar grande parte dos equipamentos recomendados, causando transtornos de diversas ordens. A avaliação da isolação acústica de pisos submetidos a impactos depende do uso de uma fonte de impacto padronizado (Standard Tapping Machine). Este é o equipamento padronizado para excitação de pisos na avaliação do nível de pressão sonora de impactos. A norma NBR 15575-3 (2013) indica a utilização do método de medição e avaliação do desempenho acústico de pisos com relação ao ruído de impactos proposto pela ISO 140-7 (1998) e ISO 717-2 (2013). No anexo A da norma ISO 140-7 (1998) são descritas as características e funções que a máquina de impacto padronizado deve cumprir. Esta pesquisa teve como objetivo construir e qualificar para uso uma fonte sonora de impacto padronizado. Para construção da fonte, observando as indicações do Anexo A da norma ISO 140-7 (1998), as partes que compõem o equipamento foram desenhadas, confeccionadas e montadas. Para qualificar o protótipo da fonte foram realizadas medidas em campo do nível de pressão sonora de impacto em sistemas piso-teto compartilhado em edifícios, conforme recomendado pela norma NBR 15575-3 (2013), empregando uma máquina de impactos comercial e repetindo o procedimento com o protótipo construído. A comparação dos níveis de pressão sonora de impacto padronizado, obtidos em função de frequências, validou numericamente a utilização do protótipo nas medições em campo realizadas. Estas medições quantificaram e qualificaram o isolamento sonoro oferecido pelos sistemas piso-teto ensaiados com relação ao ruído de impacto. Foram incorporadas inovações ao protótipo por meio da adoção de rolamentos lineares como guias para queda dos martelos e a inserção de peças resilientes sobre os contados de elevação dos martelos, reduzindo a emissão de ruído aéreo de funcionamento
Abstract: One of the most frequent complaints among inhabitants of residential buildings is the annoyance caused by noise impacts in the floor-ceiling systems resulting from walking or falling objects. According to national and international standards, assess the acoustic performance of these systems depends on the use of standardized and certified equipment. To meet the methods of assessing the acoustic performance suggested by the standards it is necessary to import most of the recommended equipment, causing disturbances of several orders. Assessment of acoustic insulation flooring subjected to impacts depends on use of a standardized source of impacts (Standard Tapping Machine). This is the standard equipment for floors excitation in the evaluation of sound pressure level impacts. The NBR 15575-3 (2013) indicates the use of the method of measurement and evaluation of acoustic performance levels with respect to noise impacts proposed by the ISO 140-7 (1998) and ISO 717-2 (2013). In Annex A of ISO 140-7 (1998) the features and functions are described that the machine must meet standardized impacts. This research aimed to construct and qualify to use a sound source of standardized impacts. For construction of the source, checking the indications in Annex A of ISO 140-7 (1998), the component parts of the equipment are designed, made and assembled. To qualify the prototype of the source were carried out measures in the field of sound pressure level of impact in floor-ceiling shared systems in buildings, as recommended by the standard 15575-3 (2013), using a commercial impact machine and repeating the procedure with the prototype built. Comparison of sound pressure levels of standardized impacts, obtained as a function of frequency, numerically validated the use of the prototype in measurements performed in the field. These measurements quantify and qualify the sound insulation provided by floor-ceiling systems tested with respect to the impact of noise. Innovations were incorporated into the prototype through the adoption of linear bearings as guides for the fall of the hammers and the inclusion of resilient pieces on the numbered elevation of hammers, reducing the emission of airborne noise operation
Mestrado
Arquitetura, Tecnologia e Cidade
Mestre em Arquitetura, Tecnologia e Cidade

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Mahasaranon, Sararat. "Acoustic and thermal properties of recycled porous media". Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5516.

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This thesis is concerned with developing porous materials from tyre shred residue and polyurethane binder for acoustic absorption and thermal insulation applications. The resultant materials contains a high proportion of open, interconnected cells that are able to absorb incident sound waves through viscous friction, inertia effects and thermal energy exchanges. The materials developed are also able to insulate against heat by suppressing the convection of heat and reduced conductivity of the fluid locked in the large proportion of close-cell pores. The acoustic absorption performance of a porous media is controlled by the number of open cells and pore size distribution. Therefore, this work also investigates the use of catalysts and surfactants to modify the pore structure and studies the influence of the various components in the chemical formulations used to produce these porous materials. An optimum type and amounts of catalyst are selected to obtain a high chemical conversion and a short expanding time for the bubble growth phase. The surfactant is used to reduce the surface tension and achieve a homogenous mixing between the solid particulates tyre shred residue, the water, the catalyst and the binder. It is found that all of the components significantly affect the resultant materials structure and its morphology. The results show that the catalyst has a particularly strong effect on the pore structure and the ensuing thermal and acoustical properties. In this research, the properties of the porous materials developed are characterized using standard experimental techniques and the acoustic and thermal insulation performance underpinned using theoretical models. The important observation from this research is that a new class of recycled materials with pore stratification has been developed. It is shown that the pore stratification can have a positive effect on the acoustic absorption in a broadband frequency range. The control of reaction time in the foaming process is a key function that leads to a gradual change in the pore size distribution, porosity, flow resistivity and tortuosity which vary as a function of sample depth. It is shown that the Pade approximation is a suitable model to study the acoustic behaviour of these materials. A good agreement between the measured data and the model was attained.

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Araujo, Bianca Carla Dantas de. "Proposta de elemento vazado acústico". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/16/16132/tde-01062010-102405/.

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O conforto ambiental requer a busca de alternativas de projeto que promovam menos impacto energético na arquitetura. Em locais de climas quentes e úmidos, a ventilação natural é uma das estratégias de projeto; inseridos nesta visão, os elementos vazados (cobogós ou combogós, com são popularmente conhecidos no nordeste brasileiro) agem como componentes arquitetônicos que proporcionam permanente ventilação natural, proteção solar e iluminação natural, além de facilidade de fabricação. Apesar do uso secular dos elementos vazados, eles perderam espaço na produção arquitetônica contemporânea, e são raras pesquisas com vistas a aprimorar seu potencial como alternativa passiva de projeto. Entretanto, existe consciência dos problemas acústicos correlatos que advém da sua utilização na ventilação natural, tais como o comprometimento na isolação dos ruídos externos e na privacidade entre ambientes. O presente trabalho, por esses motivos, tem por proposta desenvolver um elemento vazado acústico, objetivando utilizá-lo na minoração do problema da dicotomia entre os aspectos térmicos e acústicos envolvidos. O desempenho do isolamento sonoro in situ dos elementos criados foi avaliado com base na Norma ISO 140-5, tendo sido também estudado o desempenho da ventilação natural através de simulações computacionais, utilizando métodos da dinâmica dos fluidos computacional - CFD. Foram desenvolvidos 4 tipos de blocos, todos eles avaliados em diferentes montagens numa parede do tipo fachada, segundo 3 condições: fechados e abertos (com e sem material absorvente). Os resultados revelaram o quão susceptível é a transmissão do ruído em aberturas de ventilação, entretanto, resultados satisfatórios de isolamento sonoro foram obtidos, principalmente em uma das montagens (bloco tipo 3, caixa), a qual apresentou desempenho similar ao bloco fechado com um Índice de Redução de Ruído Padrão Global (Dntw) de 27 dB. Esta montagem apresenta relação de área aberta satisfatória para promover a ventilação natural dentro de um ambiente (confirmada pelo melhor desempenho comparativo de ventilação dos blocos simulados), além de apresentar isolamento sonoro superior ao de outros (poucos) elementos existentes no mercado, com o objetivo de promover a ventilação natural e reduzir a transmissão de ruído para se obter bom desempenho.
The environmental comfort requires the search for design alternatives that promote less energy impact on architecture. In places with hot and humid climates, natural ventilation is one of design strategies; into this vision, the hollow elements (cobogós or combogós, as popularly known in northeastern Brazil) act as architectural components that provide permanent natural ventilation, sun protection and natural lighting, and ease of manufacture. Despite the secular use of hollow elements, they lost space in contemporary architectural production, and there are few surveys with a view to enhancing its potential as an alternative passive design. However, there is awareness of the problems related noise that comes from its use in natural ventilation, such as commitment in the isolation of external noise and privacy between environments. In this work, for these reasons, the proposal is to develop an element hollow sound, aiming to use it in alleviating the problem of the dichotomy between the thermal and acoustic aspects involved. The performance of sound insulation in situ of the elements created was assessed based on the ISO 140-5, was also studied the performance of natural ventilation through computer simulations, using methods of computational fluid dynamics - CFD. Were developed 4 types of blocks, all studied at different mounts on a wall like facade, according to 3 conditions: closed and open (with and without sound absorption material). The results revealed how likely is the transmission of noise from the vent, however, satisfactory sound insulation were obtained, especially in one of the mounts (block type 3, box), which presented a performance similar to a closed block with index Noise Reduction Global Standard (Dntw) of 27 dB. This assembly has an open area ratio of satisfactory to promote natural ventilation in an environment (confirmed by the comparative performance of simulated ventilation of the blocks), while maintaining sound insulation than the other (few) elements in the market, with the objective to promote natural ventilation and reduce noise transmission to achieve good performance

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Shimizu, Takafumi. "Study on improvement of sound insulation performance for multi-layer windowpanes and gaps". 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215221.

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Khan, Amir. "Vibro-acoustic products from re-cycled raw materials using a cold extrusion process : a continuous cold extrusion process has been developed to tailor a porous structure from polymeric waste, so that the final material possesses particular vibro-acoustic properties". Thesis, University of Bradford, 2008. http://hdl.handle.net/10454/4289.

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A cold extrusion process has been developed to tailor a porous structure from polymeric waste. The use of an extruder to manufacture acoustic materials from recycled waste is a novel idea and the author is not aware of any similar attempts. The extruder conveys and mixes the particulates with a reacting binder. The end result is the continuous production of bound particulates through which a controlled amount of carbon dioxide gas that is evolved during the reaction is used to give the desired acoustic properties. The cold extrusion process is a low energy consuming process that reprocesses the post manufacturing waste into new vibro-acoustic products that can be used to meet the growing public expectations for a quieter environment. The acoustical properties of the developed products are modelled using Pade approximation and Johnson-Champoux-Allard models. Applications for the developed products are widespread and include acoustic underlay, insulation and panels in buildings, noise barriers for motorways and railway tracks, acoustic insulation in commercial appliances and transport vehicles.

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Ikonen, Linus, i Daniel Nilsson. "Quality assessment of mineral wool insulation plates : Using ultrasonic non-destructive testing". Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-18223.

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In the manufacturing process of mineral wool insulation plates, defects arise, such as unmelted base minerals and uncured binder which gets embedded within the plates. To be able to sort out these defective plates from a manufacturing line, a reliable quality assessment is needed. The aim is to find an ultrasonic non-destructive testing method that can identify the embedded defects. This was achieved through experiments on defective insulation plates using three different ultrasonic non-destructive testing methods that were of interest. These methods were higher harmonics, pulse-echo and through transmission. Of these three, the through transmission method showed the most promising results in finding the defects that were sought after. The through transmission method utilizes two aligned transducers, one acting as a transmitter and one as a receiver. When the defective area passes through the sound beam between the transducers the intensity of the beam drops, indicating that a defect is present. The weakened intensity is due to the signal attenuation, mainly caused by the higher density of the defects compared to the base material in the surrounding insulation plate. The method is well suited for being implemented in a production line since it’s a fast method and, therefore, suited for moving objects. More measurements are needed to establish a reliable reference value to consistently distinguish the defects from the surrounding plate. The method was only evaluated in a small scale experimental environment so further experiments on a larger scale are needed to mimic and evaluate the reliability in the real case scenario of the production lines.
I tillverkningsprocessen av isolerskivor i stenull uppstår inneboende defekter i isolerskivorna, dessa defekter består av osmälta basmineraler och ohärdat bindemedel. För att kunna sortera bort dessa skadade skivor från tillverkningslinjen behövs en pålitlig metod för kvalitetsbedömning. Avsikten med det här arbetet är att hitta en oförstörande provningsmetod baserad på ultraljud som kan identifiera de inneboende defekterna. Detta genomfördes genom experiment på defekta isolerskivor med tre olika oförstörande provningsmetoder baserade på ultraljud. Dessa metoderna var, higher harmonics, pitch-echo och through transmission. Through transmission visade lovande resultat i att identifiera de båda typerna av skador. Metoden är baserad på att en sändare sänder ut ultraljud till en mottagare placerad i linje med sändaren. När ett defekt område passerar ultraljudsvågen mellan sändaren och mottagaren försvagas intensiteten av signalen. Försvagningen av signalen beror mestadels på att densiteten är högre hos defekterna än hos basmaterialet i isolerskivan. Denna försvagning indikerar att en defekt befinner sig i mätområdet. Metoden är väl implementerbar i en tillverkningslinje, då det är en snabb metod vilket den behöver vara då objektet är i rörelse. Mer mätningar behövs för att fastställa ett pålitligt referensvärde för att konsekvent kunna sortera ut de defekta isolerskivorna. Metoden är endast utvärderad i en småskalig laborationsmiljö och det behövs fler tester i en större skala undersöka pålitligheten i det verkliga scenariot med tillverkningslinjen.

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Öqvist, Rikard. "Measurement and perception of sound insulation from 20 Hz between dwellings". Doctoral thesis, Luleå tekniska universitet, Drift, underhåll och akustik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-62843.

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Population growth and urbanization are projected by the United Nations to add 2,5 billionpeople to the world’s urban population by 2050. We need to construct buildings in anunprecedented scale to meet global housing demand. Sustainable development is critical.Compared to traditional heavy constructions, lightweight wooden constructions are moreenvironmentally friendly and will play a key role in meeting future demands. However, thereare two major problems with lightweight constructions that need to be addressed: 1) Limitedlow frequency sound insulation and 2) Variations in sound insulation.Annoyance from walking sound tend to be higher in lightweight than in heavy constructionseven with the same measured sound insulation. The Swedish research program AkuLiteindicated that the correlation between measured sound insulation and annoyance wassignificantly improved by extending current evaluation methods from 50 Hz down to 20 Hz.Secondly, large variations in sound insulation between nominally identical lightweightconstructions are common, which leads to larger safety margins. By identifying and quantifyingunderlying causes, production costs can be minimized and the performance can be improved.The aim of the thesis is to develop a new evaluation method for impact sound insulation thatbetter correspond to rated annoyance, and to identify and control underlying causes forvariations in sound insulation. The thesis contains six papers.In Paper I and II, sound insulation measurements were carried out in a large number ofnominally identical rooms of two different industrially prefabricated lightweight woodenconstructions. The purpose was to assess and quantify the variations in impact and airbornesound insulation. In Paper I, 30 nominally identical apartments of a volume based system wasevaluated. The apartments on the highest floor achieved significantly better sound insulationdue to the extra weight on lower floors affecting the elastic connections between stories. InPaper II, 18 rooms of a cross-laminated timber system of plate elements were evaluated.Additionally, several potential parameters related to measurement uncertainty wereinvestigated.Paper III deals with measurement uncertainty. An empirical study of reverberation timemeasurements showed that current methods need to be improved, if sound insulationrequirements are to be extended to 20 Hz.Paper IV and V verified that the frequency range 20-50 Hz is important for walking soundannoyance, and that alternative frequency adaptation terms can improve the correlation betweenmeasured impact sound insulation and annoyance ratings. In Paper IV, the methodology was toperform extensive field measurements in apartment buildings of various construction types andto perform questionnaire surveys among the residents. In Paper V, the methodology was toevaluate annoyance based on binaural recordings of walking sound in a two-part listening test.In Paper VI, 70 measurements in a lightweight wooden system were evaluated to quantify thetotal variations in impact and airborne sound insulation from 20 and 50 Hz, respectively. It wasconcluded that the proposed metrics of impact sound insulation were primarily determined bythe impact sound level 20-40 Hz and that the measurement methods must be evaluatedthoroughly to avoid excessive safety margins. A new evaluation method for impact sound insulation from 25 Hz, that correspond to the ratedannoyance for both heavy and lightweight constructions is proposed. By using the proposedmethod and attending the specific causes for variations, the lightweight industry will be able todevelop improved multi-story dwellings with higher perceived acoustic quality.

Forskningsfinansiärer:

Sven Tyréns Stiftelse

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RIZZO, Giuseppe. "Pulsed Electro-Acoustic space charge apparatus – qualifying, testing and monitoring of insulation for HVDC cables and accessories". Doctoral thesis, Università degli Studi di Palermo, 2022. http://hdl.handle.net/10447/533110.

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Cabrita, Ariana Reis. "Análise funcional e económica de edifícios com paredes exteriores em blocos de argila expandida". Master's thesis, Universidade de Évora, 2013. http://hdl.handle.net/10174/16074.

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A introdução de novos materiais e soluções construtivas deve dotar os edifícios de uma boa qualidade funcional, designadamente, no domínio térmico e acústico bem como não introduzir aumentos significativos de custo. A garantia de condições de conforto térmico e acústico nos edifícios pressupõe o cumprimento de um conjunto de critérios regulamentares, designadamente, o Regulamento das Características de Comportamento Térmico dos Edifícios (RCCTE), o Regulamento Geral do Ruído (RGR) e o Regulamento dos Requisitos Acústicos de Edifícios (RRAE), que devem ser cumpridos na fase de projeto e corretamente implementados na fase de execução. Este trabalho tem como principal objetivo a análise funcional e económica de edifícios com paredes exteriores em blocos de argila expandida. Para o efeito proceder-se-á à caracterização dos blocos de argila expandida, efetuar-se-á a análise térmica e acústica de um caso de estudo onde serão utilizados estes blocos na envolvente exterior e efetuar-se-á a análise técnica e económica desta solução; ABSTRACT: The introduction of new materials and construction solutions must provide a better functional quality to the buildings, particularly on thermal and acoustic behavior, but should not increase significantly its cost. To guarantee comfort conditions in buildings the construction solutions must respect a variety of criterias, in particular three regulations: RCCTE (Regulamento das Características de Comportamento Térmico dos Edifícios), RGR (Regulamento Geral do Ruído) and RRAE (Regulamento dos Requisitos Acústicos de Edifícios). These rules must be taken into account in the project stage and also correctly implemented during the construction stage. The main purpose of this dissertation is to analyze functionally and economically buildings which have exterior walls filled with expanded clay blocks. These blocs will be fully characterized and applied to a case study, analyzing its thermal and acoustic behavior and finally studying this solution technically and economically.

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Pavasovic, Vladimir, i vpavasovic@wmgacoustics com au. "The radiation of Sound from Surfaces at Grazing Angles of Incidence". RMIT University. Applied Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20060911.115939.

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It is difficult to predict the sound radiation from large factory roofs. The existing infinite panel theories of sound insulation are not sufficient when the sound radiates at grazing angles. It has been shown that the reason for the collapse of the theory is the well known result for the radiation efficiency. This research will present a simple analytic strip theory, which agrees reasonably well with numerical calculations for a rectangular panel. Simple analytic strip theory has lead to the conclusion that it is mainly the length of the panel in the direction of radiation, rather than its width that is important in determining its radiation efficiency. The findings of the current research also indicated that apart from the effect due to coincidence, a panel was non-directional compared to an opening.

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Pavarin, Cora. "ENERGY, ACOUSTICS AND ENVIRONMENTAL SUSTAINABILITY ANALYSIS OF BUILDING SYSTEMS BASED ON WOOD WOOL MINERALIZED WITH PORTLAND CEMENT". Doctoral thesis, Università degli studi di Padova, 2014. http://hdl.handle.net/11577/3425274.

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In the present work various aspects of the energetic, thermal and acoustic properties of porous materials with wood wool mineralized Portland cement have been analyzed, in cooperation with the company Celenit Srl, a manufacturer of panels for building insulation. These products are also recognized interesting and desirable for their environmental sustainability through specific certifications. Remind that sustainability means "development that meets the needs of the present without compromising the ability of future generations to meet their own needs", as formulated in 1987 by the United Nations Assembly Gro H. Brundtland. It is for these reasons that in periods of strong research in renewable energy and environmental crisis such as the current one is important to ensure the sustainability of materials, elements, components, and building processes. During the Ph.D. school some software for the evaluation of the thermal performance of the products were subjected to analysis and validation. As input data were chosen experimental values obtained in the laboratories of the Department of Industrial Engineering (DII). Sound absorption, sound reduction and impact noise tests were done in laboratory for what concern the acoustic part. These analyses have led to the development of dynamic databases for data collection and usage. The dynamic databases, processed in Excel, are collecting all the data of the acoustic tests performed in the lab at the University of Padua. In particular they have been processed two separate databases: one collecting data of airborne sound insulation and one collecting data of test acoustic absorption of materials.
Nel presente lavoro sono stati analizzati diversi aspetti relativi alle proprietà energetiche, termiche ed acustiche di materiali porosi in lana di legno mineralizzata con cemento Portland, in collaborazione con la ditta Celenit S.r.l., produttrice di pannelli per l’isolamento edilizio. Questi prodotti si rivelano interessanti e attualmente desiderabili anche per la loro sostenibilità ambientale riconosciuta tramite certificazioni specifiche. Ricordiamo che, in ambito edilizio, costruire sostenibile significa sviluppare progetti e realizzare edifici che soddisfino a pieno le esigenze degli utenti di oggi garantendo alle generazioni future di poter fare altrettanto, così come formulato nel 1987 all’Assemblea delle Nazioni Unite da Gro H. Brundtland. È per questi motivi che in periodi di forte ricerca di fonti energetiche e crisi ambientale quali quello attuale è importante garantire la sostenibilità dei materiali, degli elementi, dei componenti e dei processi edilizi. Nel corso del dottorato sono stati sottoposti ad analisi e validazione alcuni software di valutazione delle prestazioni termiche dei prodotti. Come dati di input sono stati scelti i valori sperimentali ottenuti presso i laboratori del Dipartimento di Ingegneria Industriale (DII). Sono state condotte, per quanto riguarda la parte acustica, prove di fonoisolamento, fonoassorbimento e calpestio in laboratorio. Tali analisi hanno consentito l’elaborazione di database dinamici per la raccolta dei dati e il loro utilizzo. I database dinamici, elaborati in Excel, sono la raccolta di tutti i dati dei test acustici effettuati nel laboratorio universitario di Padova. In particolare sono stati elaborati due database distinti: uno che raccoglie i dati di potere fonoisolante per via aerea ed uno che raccoglie invece i dati di test sull’assorbimento acustico dei materiali.

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Oiticica, Maria Lúcia Gondim da Rosa. "Desempenho acústico de diferentes tipologias de peitoris ventilados". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258536.

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Orientador: Stelamaris Rolla Bertoli
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-16T13:37:38Z (GMT). No. of bitstreams: 1 Oiticica_MariaLuciaGondimdaRosa_D.pdf: 8031849 bytes, checksum: 7b186c29405cc5443f860aedc6138082 (MD5) Previous issue date: 2010
Abstract: Com a crise energética na década de 60, varias discussões foram levantadas com o propósito de estimular as edificações a estarem inseridas em um contexto sustentável. As edificações, por serem grandes consumidoras dos recursos naturais, buscam ser mais eficientes energeticamente que outras quando estas proporcionam as mesmas condições ambientais com menor consumo energético. Para tal, a bioclimatologia que relaciona o estudo do clima aplicado à arquitetura, quando focada nas decisões arquitetônicas, torna-se uma excelente ferramenta para se obter valores de consumo energéticos mais baixos. Nas regiões de clima quente úmido, a utilização do peitoril ventilado como estratégia de projeto bioclimático, é uma ferramenta de projeto muito bem aplicada dentro deste conceito. O peitoril ventilado é um dispositivo geralmente executado em concreto, em formato geralmente em "L" invertido, sobreposto a uma abertura localizada no peitoril abaixo das janelas, que tem por finalidade atuar como fonte complementar do movimento de ar proporcionado pelas aberturas. A presença deste elemento nas aberturas das edificações pode proporcionar uma redução do consumo de energia, uma vez que estimula a climatização natural, mas ao mesmo tempo permite a passagem de ruído para o interior das edificações. Este trabalho tem o objetivo de investigar o desempenho acústico de diversos protótipos de peitoril ventilado, utilizados em fachadas como estratégia passiva de projeto bioclimático. Como método de avaliação acústica foi medido o grau de isolamento acústico dos peitoris ventilados através da diferença de nível sonoro padronizado mantendo-se fixa a área de abertura e variando as características construtivas do elemento de fachada investigado. Diante dos diversos materiais construtivos utilizados nos protótipos foi possível verificar significativas alterações na atenuação acústica dos diferentes modelos investigados. Com isto, registra-se que a utilização de uma estratégia passiva de projeto bem aplicada poderá propiciar em melhora nas condições acústica no interior das edificações, estimulando assim a utilização da climatização natural e consequentemente contribuindo para um menor consumo energético.
Abstract: With the energy crisis in the 60s, several discussions have been raised with the intention of stimulating the buildings to be included in a sustainable context. The buildings, being large consumers of natural resources, seek to be more energy efficient than others when they provide the same environmental conditions with lower energy consumption. To this end, the bioclimatology that connects the study of climate applied to architecture, when focused on architectural decisions, it is an excellent tool to obtain values of lower energy consumption. In regions of warm humid climate, the use of ventilated window sill as bioclimatic design strategy is a very well implemented project tool in this concept. The ventilated window sill is a device generally in "L" inverted, made on concrete, overlaid with a sill opening located below the window, mainly act as a supplementary movement of air source provided by openings. The presence of this element in the openings of buildings can provide a reduction in energy consumption since it stimulates the natural climatization, but at the same time allows the passage of noise to the interior of buildings. This work aims to investigate the sound insulation of a wall containing different prototypes of ventilated windows sill commonly used in walls as a passive bioclimatic design. The presence of this element in the openings of buildings can provide a reduction in energy consumption since it stimulates the natural air conditioning, but at the same time allows the passage of noise to the interior of buildings. This work aims to investigate the sound insulation of a wall containing different prototypes of ventilated windows sill commonly used in walls as a passive bioclimatic design. As methodology, different settings of ventilated window sill were inserted in façade of flat opening building but made of different materials. The sound insulation performance of each element used in a façade were compared and analyzed. In preliminary results it was possible to verify changes in acoustic attenuation of different types of ventilated windows sill investigated. That is, records that the use of a passive strategy and implemented the project could offer in improving thermal and acoustic conditions inside the buildings with lower energy consumption.
Doutorado
Arquitetura e Construção
Doutor em Engenharia Civil

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Ba, Abdoulaye Sidiki. "Étude de la transmission acoustique de métaplaques localement résonantes". Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0228/document.

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Les matériaux acoustiques super absorbants, sub-longueur d’ondes et large bande, ouvrent de nouvelles perspectives prometteuses pour l’isolation sonore. Dans ce contexte, nous avons conçu et synthétisé des structures hétérogènes comportant des microbilles sphériques de silicone poreux « ultra-lentes », distribuées dans des matrices aqueuses ou élastomériques. Dans un premier temps, nous avons démontré pourquoi la vitesse du son est aussi basse dans les silicones poreux (<100 m/s) comparativement à celle de milieux homogènes (~1000 m/s). Ce fort contraste de propriétés acoustiques entre phases étant susceptible d’induire des propriétés extrêmement diffusantes des microbilles, nous avons étudié l’impact de la nature de la matrice et de l’arrangement (aléatoire ou périodique) des microbilles sur les propriétés acoustiques d’échantillons se présentant sous forme de plaques sub-longueurs d’ondes à faces parallèles. Nous avons montré que la présence de minima prononcés dans le coefficient de transmission de ces métaplaques était pilotée par la résonance monopolaire des microbilles, et était fortement conditionnée par la nature de la matrice environnante. Enfin, toutes les mesures ultrasonores de l’étude ont été confrontées avec succès à des prédictions issues de modèles de diffusion multiple
Acoustic metamaterials may behave like sub-wavelength and broadband sound-absorbers, opening thus new promising routes for sound insulation. In this context, we have designed and achieved heterogeneous structures composed of soft porous silicone rubber microbeads with ultra-low sound speeds, dispersed in various aqueous or elastomeric matrices. First, we show why the sound speed is so low in soft porous silicone rubber materials (<100m/s) in comparison with soft homogeneous materials (~1000m/s). Such a large sound-speed contrast resulting in strongly scattering properties of the microbeads, we have studied the influence of the matrix characteristics as well as the arrangement of microbeads (random or ordered) on the acoustic properties of the samples in form of sub-wavelength slabs. We have evidenced deep and wide minima of acoustic transmission due to the strong monopolar resonances of the microbeads, which strongly depend on the properties of the surrounding matrix. All our ultrasonic measurements have been compared with theoretical predictions based on various Multiple Scattering Theories, revealing an excellent quantitative agreement

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Thomas, Ashwin Paul. "Simulated and laboratory models of aircraft sound transmission". Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/52319.

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With increased exposure to transportation noise, there have been continued efforts to help insulate homes from aircraft noise. Current aircraft noise guidelines are based primarily on outdoor sound levels. As people spend the majority of their time indoors, however, human perception is evidently more related to indoor sound levels. Investigations are being made to provide further insight into how typical residential constructions affect indoor response. A pilot study has built a single-room "test house", according to typical construction for mixed-humid climate regions, and has directly measured outdoor-to-indoor transmission of sound - with specific focus on continuous commercial aircraft signatures. The results of this study are being used to validate and improve modelling software that simulates a wide range of construction types and configurations for other US climate regions. The improved models will allow for increased flexibility in simulating the impacts of acoustic and energy retrofits. Overall, the project intends to improve the ability to predict acoustic performance for typical US construction types as well as for any possible design alterations for sound insulation.

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Oliveira, Marco Aurélio de. "ESTUDO DA EFICIÊNCIA DA DUPLICAÇÃO DE JANELAS NA MELHORIA DO ISOLAMENTO ACÚSTICO DESTES COMPONENTES". Universidade Federal de Santa Maria, 2007. http://repositorio.ufsm.br/handle/1/7923.

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The aim of this research is to evaluate sound insulation behavior of double windows, when a second window is placed upon a previous one, keeping an air layer between them. This was done through standard tests carried out at the reverberation chambers of the Thermo Acoustics Laboratory, of Universidade Federal de Santa Maria in accordance with ISO 140-III, ISO 717-I international norms and the Brazilian Norm Project 02:135.01-001. First, low air hermetic windows were duplicated, each one having Rw = 18 dB. Second, good air hermetic windows were duplicated. The objective, through this technique, was to find out sound insulation improvement of double windows under the two mentioned circumstances. Observing the test results, it was verified that low air hermetic double window obtained Rw = 26 dB, with an increase of 8 dB in relation to just one window of the same typology. Insulation gain, in this case, occurred mainly in medium and high frequencies. In relation to good air hermetic double window, a Rw final of 37 dB was obtained, considering that the increase in sound insulation depends on the initial performance of the fist installed window. The gain in insulation in the second instance was between 4 to 8 dB, mainly in relation to low and medium frequencies. Therefore, it was possible to quantify which sound insulation improvement could be done on façades employing the technique of double windows in order to contribute to the betterment and quality of buildings in Brazil
A proposta deste trabalho é avaliar o comportamento da isolação sonora de janelas duplas, em que uma segunda janela é sobreposta a outra já existente, havendo entre ambas uma camada de ar. Tal determinação é feita mediante ensaios normalizados nas câmaras reverberantes do Laboratório de Termo Acústica da Universidade Federal de Santa Maria, de acordo com as normas internacionais ISO 140-III, ISO 717-I e Projeto de Norma Brasileira 02:135.01-001. Inicialmente foram duplicadas janelas com baixa estanqüeidade ao ar, tendo Rw = 18 dB cada uma, e a seguir, janelas com boa estanqüeidade. Buscou-se, através dessa técnica, conhecer o desempenho sonoro da duplicação de janelas nestas duas situações consideradas. A partir dos resultados dos ensaios, verificou-se que a duplicação de janelas com baixa estanqüeidade ao ar atingiu um Rw = 26 dB, com acréscimo de 8 dB em relação à uma única janela de mesma tipologia. O ganho de isolamento, nesse caso, ocorreu principalmente nas médias e altas freqüências. Em relação à duplicação de janelas com boa estanqüeidade, atingiu-se um Rw final de 37 dB, sendo o acréscimo no isolamento acústico dependente do desempenho inicial da primeira janela. O ganho em isolamento nesta segunda situação foi de 4 a 8 dB, com incidência sobretudo nas baixas e médias freqüências. Dessa maneira, pôde-se quantificar qual a melhoria do isolamento sonoro em fachadas, a partir da duplicação de janelas, de forma a contribuir para o aperfeiçoamento e qualidade das construções em nosso país

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Bernabè, Marco. "Space charge and dielectric response measurements to assess insulation aging of low-voltage cables used in nuclear power plants". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/4824/.

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The current design life of nuclear power plant (NPP) could potentially be extended to 80 years. During this extended plant life, all safety and operationally relevant Instrumentation & Control (I&C) systems are required to meet their designed performance requirements to ensure safe and reliable operation of the NPP, both during normal operation and subsequent to design base events. This in turn requires an adequate and documented qualification and aging management program. It is known that electrical insulation of I&C cables used in safety related circuits can degrade during their life, due to the aging effect of environmental stresses, such as temperature, radiation, vibration, etc., particularly if located in the containment area of the NPP. Thus several condition monitoring techniques are required to assess the state of the insulation. Such techniques can be used to establish a residual lifetime, based on the relationship between condition indicators and ageing stresses, hence, to support a preventive and effective maintenance program. The object of this thesis is to investigate potential electrical aging indicators (diagnostic markers) testing various I&C cable insulations subjected to an accelerated multi-stress (thermal and radiation) aging.

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Mahmoud, Mohamad. "Design, Fabrication, and Characterization of Monolithically Integrated Acoustic and Photonic Devices on Lithium Niobate Over Insulator (LNOI) Platform". Research Showcase @ CMU, 2018. http://repository.cmu.edu/dissertations/1133.

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Integration of acoustics and photonics devices on the same chip will enable various applications including: building miniaturized sensors, on-chip filtering and optical signal processing, high speed modulation, as well as non-linear optical devices. As an example of the capabilities enabled by such integration, we target the development of a rotation sensor gyroscope based on the acousto-optic effect. The gyroscope components are integrated on a Lithium Niobate Over Insulator (LNOI) substrate because it is a unique platform that exhibits exceptional acoustic as well as photonic properties. However, acoustics and photonics have never been integrated on such substrate, which required the development of a new fabrication process and the design of novel components.. The main challenges we had to overcome and resulted in innovative demonstrations of fabrication processes and devices are:  Developing a robust fabrication process for etching lithium Niobate (LN) waveguides and integrating them with acoustic transducers: A robust fabrication process was developed on the LNOI platform, which can integrate patterning sub-micron features together with microscale ones on the same 3’’ substrate. Furthermore, the developed fabrication process enabled integrating metallic Al electrodes together with etched LN waveguides, which is required for building various components like electro-optic modulators and acousto-optic modulators.  Coupling light in and out of chip: Gratings couplers were designed for optimum coupling of the TE polarized light. The optimization was based on FDTD simulation on LUMERICAL. The grating couplers realization enabled estimation of the light coupling loss in and out of the chip. The measured coupling loss was about 9 dB per coupler in the best case which is much more than the estimated from simulation. That difference is attributed to the alignment accuracy of the photonic chip.  Integrating photonic waveguides/resonators and coupling light between them: LNOI waveguides and photonic resonators were designed and built. The photonic resonators enabled extraction of the losses of waveguides by monitoring the photonic resonator Quality factor, Q, or Finesse (F). Directional couplers (DCs) are commonly used as coupling elements to photonic resonators. However, etching narrow gaps in LN is a challenge that we avoided by using multi-mode interference (MMI) couplers, where butterfly MMI couplers were designed as coupling element to photonic racetrack (RT) resonators aiming for critical coupling condition. Additionally 3-dB MMI couplers were designed to be used as beam combiners in the Mach-Zehnder interferometer (MZI). The built RT resonators enabled extraction of the propagation losses in the etched LNOI photonic waveguides, which were found to be equal to2.5 dB/cm.  Building high efficiency electro-optic modulators (EOMs): The EOM is used in the AOG to compensate for temperature variations and other environmental variation affecting the rotation measurement. The EOM realization enabled extraction of the electro-optic (EO) coefficient for the LN thin film, which permits to evaluate the magnitude of the control voltages required to stabilize the system. EOMs of two different types were demonstrated, one is based on a photonic RT while the other is based on an Asymmetric MZI (AMZI). The RT EOM represents the first demonstration for such device with etched waveguides in Y cut LNOI platform. Modulation bandwidth of 4 GHz, wavelength tuning rate of 0.32 pm/V and an ER of more than 10 dB were experimentally measured for the RT EOM. For the AMZI, a half wave voltage length product of 16.8 Vcm was experimentally measured. Although, it is not the best we can get from this LNOI platform because of our wide waveguides, feeding that EO coefficient to the AOG system model ensures that the temperature variation from -54 oC to 25 oC can be compensated by applying a maximum voltage of 64.5 V.  Building efficient acousto-optic modulators (AOMs): The AOM enabled the extraction of the acousto-optic (AO) coefficient, which directly impacts the AOG scale factor (SF). Additionally, two different types of AOMs were demonstrated, one is based on an MZI embedded inside a SAW cavity while the other is based on a photonic RT whose coupling condition is under EO control. For the MZI AOM, the SAW resonator enhances the modulation efficiency due to the resonator Q such that the phase shift per square root of power extracted from the measurements is a factor of 3x higher than what previously reported on a GaAs platform, which makes it, to the author’s knowledge, effectively the highest AO modulation ever attained on chip. On the other hand, the EO tuned RT AOM showcases integration of various functionalities on same platform to build efficient AOM that can be operated at the desired wavelength. The EO tuning not only changes the operating optical wavelength but also ensures the critical coupling condition needed for efficient modulation. This design takes advantage of the unique AO and EO properties of LN, hence showcasing important building blocks for RF-photonic applications. By addressing all the previous challenges through the demonstration of high performance components, we were able to prototype the first acousto-optic gyroscope. That prototype represents the first demonstration of a novel rotation sensing technique, which combines the following advantages: (i) large mass (there is no suspended mass in the sensing mechanism and hence no limits on increasing the mass and no concerns about stiction issues during fabrication), and (ii) high shock resistance (since the sensing mechanism is strain based, the AOG has no moving parts that would not survive high G accelerations). The AOG SF is estimated comparing three photonic phase sensing techniques which are MZI, RT as well as RT coupled to MZI (MZI/RT). The phase sensitivity is estimated in terms of the cavity F for each technique. That theoretical analysis is verified by experimental measurement for the SF for both the MZI and the RT AOGs. The measured SF for the MZI is 48 nv/(o/sec) while it is about 9 nv/(o/sec) for the RT AOG. The SF is lower for the RT AOG because the Finesse (F~6) of the RT is not as high as expected. Nevertheless, these prototypes represent a proof of concept for our novel method for sensing rotation. Future work could prove that this AOG concept could be disruptive. Reducing the losses in the LNOI waveguide is a key challenge that can be overcome and has been already demonstrated by other groups showcasing 100x lower propagation loss. The estimated F from our model in that case would increase by approximately 50x, hence improving the gyroscope SF by the same factor. Further improvement of 100x is possible by increasing the SAW wavelength and Q. A separate challenge that needs to be addressed is the laser and photodetector integration on chip, which will reduce the coupling loss and the sensitivity to optical alignment.

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Januševičius, Tomas. "Research on the acoustic qualities of building materials and structures and their use for noise reduction in premises". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110621_170924-08631.

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The dissertation analyses the sound-insulating qualities of building materials and structures. The aim of the dissertation is to investigate and indentify, under natural conditions and in a noise suppression chamber, the structures which, as internal and external components of buildings, would ensure the protection of inte-rior rooms against noise and to model on this basis the sound reduction indices of structures. The work deals with several main tasks: investigations of the acoustic quali-ties of building materials and structures in a noise suppression chamber and under natural conditions; comparison of results obtained from measurements, and the evaluation of the sound reduction indices of perspective structures through model-ling. The introductory chapter introduces the problem addressed and topicality of the work, describes the object of research, formulates aim and tasks of the work, describes research methodology, scientific novelty of the work, points out practi-cal value of the work’s results and specifies defended propositions. The introduc-tion ends with a list of articles on the dissertation topic published by the author and the structure of the dissertation. The first chapter analyses literature relating with the dissertation topic. Con-clusions are formulated at the end of the chapter. The beginning of each chapter presents research methodologies. The second chapter differentiates investigations which were carried out in a noise suppression chamber and... [to full text]
Disertacijoje nagrinėjamos statybinių medžiagų ir konstrukcijų garso izoliaci-nės savybės. Disertacijos tikslas – natūrinėmis sąlygomis ir triukšmo slopinimo kameroje ištirti ir nustatyti konstrukcijas, kurios, kaip pastatų vidinės ir išorinės sudėtinės dalys, užtikrintų vidaus patalpų apsaugą nuo triukšmo, ir tuo pagrindu sumodeliuoti konstrukcijų garso izoliavimo rodiklius. Šiame darbe sprendžiami keli pagrindiniai uždaviniai: statybinių medžiagų ir konstrukcijų akustinių savybių tyrimai triukšmo slopinimo kameroje ir natūrinė-mis sąlygomis, matavimų rezultatų palyginimas, perspektyvių konstrukcijų garso izoliavimo rodiklių įvertinimas modeliavimo būdu. Disertaciją sudaro įvadas, aštuoni skyriai, rezultatų apibendrinimas, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašas. Įvadiniame skyriuje pristatoma tiriamoji problema, darbo aktualumas, apibū-dinamas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, nusakomas darbo mokslinis naujumas ir darbo rezultatų praktinė reikšmė, išvardijami ginamieji teiginiai. Įvadas baigiamas disertacijos tema auto-riaus paskelbtų publikacijų ir pranešimų konferencijose pristatymu bei disertacijos struktūra. Pirmajame skyriuje analizuojama su disertacijos tema susijusi literatūra. Sky-riaus pabaigoje formuluojamos išvados. Tyrimų metodikos pateiktos kiekvieno skyriaus pradžioje. Antrajame skyriuje išdiferencijuojami triukšmo slopinimo kameroje vykdyti tyrimai ir analizuojami jų... [toliau žr. visą tekstą]

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Dahlström, Hannes, i Alexander Dyk-Strömberg. "Lätta väggar, högt buller". Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-44434.

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En av modern tids största miljöproblem anses vara buller. Bland annat kan nedsatt fysisk hälsaoch mental stress förekomma för människor som utsätts för bullerexponering. Ökande önskan om god akustisk miljö är idag i konflikt med att pågående urbanisering gör att vi utsätts för ökad bullerexponering i våra bostadsmiljöer. Urbaniseringen har lett till framställningen av en förordning som är fördelaktig för mer expansivt bostadsbyggande i bullerutsatta miljöer.Förordningen möjliggör byggnation vid högre trafikbullernivåer än tidigare tillåtet. Med avseende på tidigare kravnivåer har fasadväggar generellt ansetts ha mer än tillräcklig ljudisoleringsförmåga att klara trafikbullernivåerna. Till följd av nu gällande förordning är det nu inte lika entydigt att fasader med lättbyggnadsteknik har tillräckligt god ljudreduktionsförmåga. Av dessa anledningar är det aktuellt att studera hur bra fasader av lättbyggnadsteknik klarar att reducera bullret för att erfordra en kravställning på ekvivalentljudtrycksnivå inomhus som motsvarar ljudklass C eller B.Studien syftar till att undersöka om lättbyggnadsteknik är lämpligt i bullerutsatta områden som tillåts av dagens bullerkravställning. Målet är att erhålla en konstruktion i lättbyggnadsteknik som lämpas att byggas i denna höga bullerexponering. Frågeställningar ämnar att reda ut hur resultaten på väggarnas ljudisoleringsförmåga förhåller sig mellan de olika empiriska insamlingarna och dessutom hur de presterar gentemot dagens kravställningar.I rapporten genomförs akustiska fältmätningar av reduktionstalet (ljudisoleringen) enligt svenskstandard på tre fasadväggar av lättbyggnadsteknik. Fasadväggskonstruktionerna modelleras även i programvaran Insul 8 för att genom detta erhålla väggarnas beräknade reduktionstal. På en av fasadväggarna undersöks även det modellerade reduktionstalets variation följandemodifieringar av väggkonstruktionens uppbyggnad. Väggarna jämförs även med riktvärden förtre referensväggar redovisade i litteratur.Genom det teoretiska underlaget har resultaten från mätningarna, modelleringarna och litteratur-riktvärden utvärderats i förhållande till om de uppnår kravnivåer på ekvivalent ljudtryck inomhus. Resultaten för rådande fallundersökningar visar att alla undersökta väggar har erforderlig ljudreduktionsförmåga för att uppnå samhällets minimikrav (ljudklass C) då ljudreduktionen dimensioneras med väggen som dimensionerande fasadelement. Med avseende på fönster som dimensionerande fasadelement klarar två av sex väggar ej att uppnå inomhusnivåer för ljudklass C. Då kravnivåerna avser att upprätta en ännu bättre ljudmiljö (ljudklass B) än minimikraven så erhåller fyra av sex väggar denna erforderliga ljudisolering med vägg som dimensionerande element. För att uppnå ljudklass B då fönstrets ljudreduktion är dimensionerande så har en fältmätning, en referensvägg och två väggmodelleringar (utan modifieringar) erforderlig ljudisolering.Slutsatserna påvisar att ljudisoleringen är generellt sett erforderlig för väggarna i lättbyggnadsteknik, även i bullerutsatta områden som tillåts av dagens kravställning. Att kunnauppnå en god ljudmiljö (ljudklass B) avseende ekvivalent ljudtryck inomhus är däremot ej självklart då väggar i lättbyggnadsteknik byggs på bullerexponerad plats. Möjligheten att förbättra reduktionstalet är möjligt och tillämpbart genom att öka massan eller minska styvheten på väggen om reduktionstal är undermåliga.
This thesis evaluates whether walls with light-frame construction are suitable to build in areas with high sound pressure levels, allowed by Sweden’s law regarding loud traffic noise nearbuildings. Previous consensus has been that exterior walls have sufficient sound insulation,regarding sound pressure levels by the residence-façade generated from traffic noise, to achieverequired indoor sound pressure levels. Due to the ongoing urbanization in Sweden, a law haspassed that increased the allowed levels of equivalent sound pressure by a residence-façade. Therefore, it has become relevant to examine if light-frame construction façades really do have sufficient sound insulation.In the study, field measurements are made on three façade walls to determine their noise reduction properties. The values from the measurements are compared to the sound insulation capacity of software-built wall-models with the same wall constructions as the field measured walls. Both the measured and the modelled walls sound insulation is also compared parallel to insulation values for light-frame construction walls found in literature. The values of the walls sound insultation are also evaluated regarding high but occurring sound pressure levels by facades and demanded levels of sound pressure indoors. Modifications are made to the construction of one modelled wall to quantify the improvement in sound insulation of the walls derived from the investigated construction-modifications.The results conclude that the examined light-frame construction walls are indeed sufficient in the aspect of sound insulation to merely satisfy the laws. The walls sound insulation is not as unambiguously sufficient when establishing what is considered a good indoor acoustic environment, instead of only achieving minimum levels required by law.

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Scherer, Cláudio Trindade. "Desempenho acústico de sistemas de vedações verticais internas: avaliação de conjuntos de portas e paredes separadas pelo hall de entrada". Universidade do Vale do Rio dos Sinos, 2017. http://www.repositorio.jesuita.org.br/handle/UNISINOS/6803.

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O conjunto de paredes e portas separadas pela circulação condominial em edifícios residenciais passou a ter seu desempenho acústico avaliado, a partir da entrada em vigor da norma brasileira NBR 15575, que trata do desempenho das edificações. Nesse contexto, esse trabalho propõe determinar a influência das características dos elementos construtivos – portas e circulações entre unidades habitacionais – no isolamento ao ruído aéreo do conjunto de paredes e portas separadas pelo hall de entrada. Primeiramente foi realizado um estudo piloto que envolveu ensaios em campo feitos em diversas obras. Com isso, foram escolhidos três prédios e executados uma série de ensaios de desempenho acústico em campo, abrangendo diversas situações. Também foram usados artifícios para a vedação das frestas das portas, a fim de verificar a melhora do desempenho do sistema. Os resultados obtidos apontam para a perda de desempenho acústico com o aumento das frestas entre a folha da porta e o piso. Foram encontradas também relações com tempo de reverberação dos ambientes de circulação e a distância entre as portas de entrada das unidades habitacionais.
Sets of walls and doors separated by condominium corridors in residential buildings started having their acoustic performance evaluated when the Brazilian standard NBR 15575 came into effect, which concerns the performance of buildings. In this context, this study proposed to determine the influence of the characteristics of constructive elements – doors and corridors between residential units – on the airborne sound insulation of the set of walls and doors separated by the entrance hall. First, a pilot study was conducted based on tests performed on many buildings, but it was noted that a deeper study on the subject would be required. Thereby, three buildings were chosen and a series of acoustic performance tests was executed, covering several situations. Maneuvers for sealing door gaps were used as well, in order to assess the performance gains of the system. The results indicated loss of acoustic performance when there were more gaps between the door leaf and the floor. Moreover, relations were found regarding the reverberation time of the corridors and the distance between the entrance doors of residential units.

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Robert, Rene Jean. "Measuring noise level reduction using an artificial noise source". Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54480.

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Buildings located near airports may be subjected to significant noise levels due to aircraft flyovers. Aircraft noise is particularly annoying when compared to other traffic noises due to its intermittent nature. While noise control is typically performed at the source, sound insulation programs are in place to improve the acoustic performance of a residence affected by the flyovers. Noise Level Reduction (NLR) is a common metric used in the United States to determine whether a residence qualifies for such programs. Sound insulation programs are available to houses that have an indoor Day Night Average Sound Level (DNL) greater than 45 dBA. NLR is a single-number metric used to quantify the ability for a building or building element to reduce the transmission of external sound pressure levels generated by aircraft. In addition to determining whether a residence qualifies, NLR can be used to quantify the effectiveness of the modifications performed as a result of the sound insulation program. NLR measurements with a loudspeaker offer an alternative method to those performed with aircraft flyovers, offering flexibility to the consultants that perform these measurements in the field. The purpose of this research was to better understand and improve the loudspeaker test for measuring NLR, providing a resource to the aircraft noise industry. Testing was completed on a "test house" that was constructed on campus with construction methods typical of a mixed-humid climate. The angular dependency, repeatability, and reproducibility of NLR, among other factors, were evaluated with field measurements. Significant NLR variations were observed with changes in lateral and vertical angles of incidence.

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Peterková, Jitka. "Vývoj a výzkum environmentálně úsporných izolačních materiálů". Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-233791.

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Increasing demand for new progressive construction materials requires development of modern environmentally friendly materials with excellent end-use properties and reasonable price. One of the main objectives of material research in building industry is using renewable resources of raw materials of industrial waste for development of new construction materials. Current trend of thermal insulation of building constructions results in development of environmentally friendly insulation materials based on renewable material resources from agriculture and stock farming, which could became alternative for current common use insulation materials in the future. The thesis describes research and development of insulation materials based on natural fibres of agricultural origin; in particular fibres of hemp, flax and jute. Hydrothermal behavior of developed materials is studied including computational simulation of behavior of researched materials after building in the construction.

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Righi, Paulo César da Rosa. "AVALIAÇÃO DO DESEMPENHO ACÚSTICO DAS EDIFICAÇÕES PARA FINS DE FINANCIAMENTO IMOBILIÁRIO". Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/7815.

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Most of the Brazilian habitation necessity is supplied by builds financed by real estate institutions. The institutions receive as guarantee the own property financed. Those companies analyze the projects of the enterprises according to technical and professional criteria of its own to the grant of subsidies and comply with the social habitation programs. It was found that, despite the Caixa Econômica Federal is the main financing entity of the real estate business of the country and participating of studies and debates about the validity of the ABNT 15575 norm Housing Buildings Performance, in their analysis to the grant of real estate credit the buildings acoustic parameters are not contemplated yet. Considering that both traffic and neighbors noise bother the people inside their residences it s possible to presume that those buildings do not show a proper performance about acoustic insulation, and, therefore, it isn t complying with of its purpose that is to provide acoustic comfort. The Technical Norms of ABNT NBR 15575, internal normative manuals of the Caixa Econômica Federal, technical documents and studies for the quantification of the acoustic parameters of the buildings were analyzed. In this study acoustic isolation coefficients determined in laboratory and field tests that represent most of the constructive elements used in this country, with data obtained through classical acoustic books and academic works about the subject were used. Were developed a tool composed by 2 electronic worksheets to subsidize the technical analysis of the real estate by the financial institutions in order to ensure that the priority be given to residential enterprises with better acoustic performance. The Worksheet A is about insulation and acoustic insulation, it means, relative to laboratory and field tests and, the Worksheet B is only about acoustic insulation, in other words, relative to field tests. From the report of the worksheets results, will be suggested the creation of one annex to the Caixa Econômica Federal Engineering Analysis Report, in order to contemplate the acoustic performance of the housing and to verify the minimum attendance to the performance norm ABNT 15575, as well as, the attendance level (minimum, intermediate or superior) of the forefront systems, inner seal walls, floor systems and coverage of the housing buildings.
Grande parte da necessidade habitacional brasileira é suprida por obras financiadas através de instituições de crédito imobiliário. As instituições financiadoras recebem como garantia o próprio imóvel financiado. Estas empresas analisam os projetos dos empreendimentos com critérios técnicos próprios para concessão de subsídios e enquadramento nos programas de habitação. Verificou-se que o principal órgão financiador do crédito imobiliário do país está participando de estudos e debates sobre a vigência da Norma ABNT 15575 Edificações Habitacionais Desempenho. Porém, em suas análises para concessão de crédito imobiliário ainda não estão contemplados os parâmetros acústicos das edificações. Considerando-se que os ruídos de tráfego e da vizinhança causam incômodo às pessoas no interior de suas residências, é possível pressupor que estas não apresentam um bom desempenho quanto ao isolamento acústico e, portanto, não estão cumprindo uma de suas finalidades, que é a de proporcionar conforto acústico a seus ocupantes. Foram analisados a Norma Técnica da ABNT, NBR 15575, Manuais Normativos da Caixa Econômica Federal, documentos técnicos e estudos disponíveis para quantificação dos parâmetros acústicos das edificações. Neste estudo, foram utilizados coeficientes de isolamento acústico determinados em ensaios de laboratório e a campo que representaram grande parte dos elementos construtivos utilizados no país. Os dados foram obtidos em livros clássicos de acústica e em trabalhos acadêmicos sobre o tema. Desenvolveu-se uma ferramenta composta por duas planilhas eletrônicas para subsidiar as análises técnicas do crédito imobiliário pelas instituições financiadoras, a fim de assegurar que sejam privilegiados os empreendimentos residenciais com melhor desempenho acústico. A Planilha A trata de isolação e isolamento acústico, ou seja, referente a testes em laboratório e a campo e, a Planilha B trata somente de isolamento acústico, ou seja, referente a testes realizados a campo. A partir do relatório de resultados das planilhas eletrônicas, pode ser verificado o atendimento à norma de desempenho ABNT NBR 15575, bem como, o nível de desempenho acústico dos sistemas de paredes de vedação internas e externas, sistemas de pisos e sistemas de coberturas acessíveis das Edificações Habitacionais.

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Mlynářová, Jana. "Vývoj izolačních materiálů na bázi druhotných textilních vláken nižší kvality". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2021. http://www.nusl.cz/ntk/nusl-433614.

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This diploma thesis is focused on a suitable midification of acoustic and thermal insulation materials from recycled textile fibres of lower quality due to improvement of their reaction to fire. The aim is to find an effective flame retardant and to verify suitable method of flame retardant application onto this type of insulation material.

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Zlámal, Josef. "Kryty pracovního prostoru stroje". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254184.

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The master thesis deals with the problematics of machine guard. The first part of the thesis is focused on the analysis of machine guards, legislative safety requirements and noise issues. The second part of the thesis describes design and construction of the machine guard in case of the vertical turning centre, TOSHULIN - POWERTURN 2000, including the calculation of noise reduction.

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Ващишак, І. Р. "Удосконалення методів безконтактного контролю стану підземних теплових мереж". Thesis, Івано-Франківський національний технічний університет нафти і газу, 2012. http://elar.nung.edu.ua/handle/123456789/1774.

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Дисертація присвячена питанню контролю технічного стану підземних теплових мереж безканальної прокладки з пінополіуретановою ізоляцією. Проведено класифікацію видів основних дефектів підземних теплових мереж з трубопроводами в пінополіуретановій ізоляції. Теоретично досліджено залежність струму у стінках трубопроводу від зміни значень діагностичних ознак, що зумовлені наявністю дефекту. Розроблено аналітичну модель поширення збуджених акустичних коливань від трубопроводу до поверхні грунту. Отримано вираз залежності акустичного тиску на поверхні ґрунту від інтенсивності акустичного збудження трубопроводу, яка враховує акустичні характеристики середовищ на шляху поширення акустичної хвилі. Досліджено залежності теплових втрат тепломережі від теплових характеристик ізоляційного покриття трубопроводу та ґрунтових засипок. Розроблено та виготовлено установку для експериментальних досліджень двохтрубної підземної теплової мережі з трубопроводами в пінополіуретановій ізоляції з різними видами дефектів. Розроблено метод ідентифікації видів дефектів підземних теплових мереж з трубопроводами в пінополіуретановій ізоляції за трьома інформативними параметрами (струмом у стінках трубопроводу, акустичним тиском на поверхні ґрунту, температурою приповерхневого шару ґрунту над тепломережею). Розроблено експериментальний взірець інформаційно-вимірювальної системи для виявлення дефектів у безканальних підземних теплових мережах. Розроблено проект нормативного документу (СОУ) на методику проведення контролю технічного стану підземних теплових мереж з трубопроводами в пінополіуретановій ізоляції.
Dissertation is devoted to the problem of technical state inspection of underground trenchless heat networks with urethane foam insulated pipes. The classification of main types of underground heat networks defects with urethane foam insulated pipes is performed. It is theoretically examined the pipeline wall ground current dependence on diagnostic indicators changes that caused be the defects. The mathematical model of excited acoustic vibrations propagation from pipeline to the ground surface is developed. It is obtained ground surface acoustic pressure dependence on level of pipeline’s acoustic excitation that considers acoustic properties of environments on the way of acoustic wave propagation. Heat network’s thermal losses dependencies on thermal properties of insulation coating of pipeline and cover materials is examined. The unit for experimental research of double line underground heat network with urethane foam insulated pipelines with different defects is developed and produced. It is developed an identification method of defect types of underground heat network using three informative parameters (current in pipeline walls, acoustic pressure, ground current, and temperature of near-surface soil over heat network). The prototype of information and measuring system for defects location detection in trenchless underground heat networks is developed. It is drafted the normative document on inspection technique of technical condition of underground heat networks with urethane foam insulated pipelines.

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Peiró, Torres María del Pilar. "Research of the acoustic phenomenon produced by isolated scatterers and its applicability as a noise reducing device in transport infrastructures. Search for an optimised and sustainable design". Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/164903.

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[ES] El control de ruido ambiental es una preocupación de primera magnitud para las sociedades avanzadas, debido a los problemas derivados que ocasionan en la salud de los ciudadanos. Una de las soluciones más extendidas para el control del ruido en su fase de transmisión en la utilización de pantallas acústicas. La aparición de nuevos materiales formados por redes de dispersores acústicos aislados, denominados cristales de sonido, está revolucionando el campo del apantallamiento acústico, posibilitando el avance tecnológico de esta área. Así, en los últimos años, las pantallas acústicas basadas en cristales de sonido se han posicionado como una alternativa viable a las pantallas acústicas tradicionales, puesto que ofrecen múltiples ventajas frente a las soluciones actuales. En el presente trabajo se muestra primeramente una recopilación de los avances realizados en el campo del apantallamiento acústico mediante esta tipología de pantallas. No obstante, aún existen líneas de investigación abiertas en esta área, que es necesario abordar para conseguir el objetivo de aplicar esta tecnología como atenuadores de sonido en las infraestructuras de transporte. Durante el periodo de formación de la doctoranda, se ha trabajado en algunas de las líneas de investigación activas en este campo del apantallamiento acústico. Una de estas investigaciones condujo al descubrimiento de interferencias entre los efectos de la resonancia y la dispersión múltiple de los cristales de sonido cuando estos efectos se producen en rangos de frecuencia cercanos. También hemos diseñado un nuevo dispositivo de reducción de ruido basado en cristales de sonido, utilizando herramientas de optimización multiobjetivo, que permitan apantallar y reflejar de forma difusa el ruido. El empleo de esta nueva herramienta de diseño identificó la necesidad de realizar un estudio comparativo de los métodos de simulación más utilizados para estimar el rendimiento de los dispositivos basados en cristales de sonido. Por último, hemos realizado un estudio psicoacústico para determinar la percepción de la reducción de molestia que proporcionan las pantallas acústicas basadas en cristales sonido y las barreras tradicionales, determinando si los parámetros objetivos que evalúan su rendimiento coinciden con la respuesta subjetiva de los usuarios.
[CA] El control de soroll ambiental és una preocupació de primera magnitud per a les societats avançades, a causa dels problemes derivats que ocasionen en la salut dels ciutadans. Una de les solucions més esteses per al control del soroll en la seua fase de transmissió en la utilització de pantalles acústiques. L'aparició de nous materials formats per xarxes de dispersors acústics aïllats, denominats cristals de so, està revolucionant el camp de l'apantallament acústic, possibilitant l'avanç tecnològic d'esta àrea. Així, en els últims anys, les pantalles acústiques basades en cristals de so s'han posicionat com una alternativa viable a les pantalles acústiques tradicionals, ja que oferixen múltiples avantatges enfront de les solucions actuals. En el present treball es mostra primerament una recopilació dels avanços realitzats en el camp de l'apantallament acústic per mitjà d'esta tipologia de pantalles. No obstant això, encara hi ha línies d'investigació obertes en esta àrea, que és necessari abordar per a aconseguir l'objectiu d'aplicar esta tecnologia com a atenuadors de so en les infraestructures de transport. Durant el període de formació de la doctoranda, s'ha treballat en algunes de les línies d'investigació actives en este camp de l'apantallament acústic. Una d'estes investigacions va conduir al descobriment d'interferències entre els efectes de la ressonància i la dispersió múltiple dels cristals de so quan estos efectes es produïxen en rangs de freqüència pròxims. També hem dissenyat un nou dispositiu de reducció de soroll basat en cristals de so, utilitzant ferramentes d'optimització multiobjectiu, que permeten apantallar i reflectir de forma difusa el soroll. L'ús d'esta nova ferramenta de disseny va identificar la necessitat de realitzar un estudi comparatiu dels mètodes de simulació més utilitzats per a estimar el rendiment dels dispositius basats en cristals de so. Finalment, hem realitzat un estudi psicoacústic per a determinar la percepció de la reducció de molèstia que proporcionen les pantalles acústiques basades en cristals so i les barreres tradicionals, determinant si els paràmetres objectius que avaluen el seu rendiment coincidixen amb la resposta subjectiva dels usuaris.
[EN] Control of environmental noise is a major concern for advanced societies because of the resulting problems for citizens' health. One of the most widespread solutions for controlling noise in its transmission phase is the use of acoustic screens. The emergence of new materials made up of arrays of isolated acoustic scatterers, called sonic crystals, is revolutionizing the field of acoustic screening. In recent years, acoustic screens based on sonic crystals have positioned themselves as a viable alternative to traditional acoustic screens, as they offer multiple advantages over current traditional solutions. This Doctoral dissertation compiles the advances in the field of acoustic screening using this type of sonic crystals. However, there is still active research in this area which needs to be addressed and studied in order to apply this technology as noise reduction devices in transport infrastructures. Therefore, during the PhD student's training period, we have researched the acoustic phenomena produced by isolated scatterers in order to better understand the physical phenomena behind the lasts designs of this type of screen. One of these researches led to the discovery of interferences between the effects of resonance and multiple scattering of sonic crystals when occurring in nearby frequency ranges. Also we have designed a new noise reduction device based on sonic crystals, using multi-objective optimization tools, which would block and diffuse the noise. This new designing tool identified the need for a comparative study of the most commonly used simulation methods to estimate the performance of devices based on sonic crystals. Finally, we have carried out a psychoacoustic study that determined the perception of the annoyance reduction provided by acoustic screens based on sonic crystals and traditional barriers, determining whether the objective parameters that evaluate their performance match to the subjective response of the users.
Agradezco al Ministerio de Ciencia e Innovación por la ayuda concedida dentro del programa Doctores Industriales. Asimismo, a mi tutor en empresa Dr. Juan José Martín Pino, por posibilitar la realización de esta investigación dentro de la empresa BECSA. Al Departamento de Física Aplicada de la Universitat Politècnica de València, a la Comisión Académica del Programa de Doctorado de Matemáticas y al Centro de Tecnologías Físicas: Acústica, Materiales y Astrofísica.
Peiró Torres, MDP. (2021). Research of the acoustic phenomenon produced by isolated scatterers and its applicability as a noise reducing device in transport infrastructures. Search for an optimised and sustainable design [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/164903
TESIS

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Massy, Damien. "Etude de la dynamique de fracture dans la technologie Smart Cut™". Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAY101.

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La technologie Smart Cut™ est un procédé générique de transfert de couches minces utilisé pour la fabrication des substrats silicium sur isolant (SOI) à l’échelle industrielle. L’implantation d’ions légers dans un substrat de silicium oxydé mène à la formation d’une zone fragilisée enterrée au sein du cristal. Ce substrat implanté est ensuite solidarisé à un support mécanique grâce à la technique de collage par adhésion moléculaire. Sous l’effet de la température, les espèces implantées évoluent sous la forme de microfissures qui se développent de manière parallèle à la surface. Après recuit, une fracture se déclenche au niveau de la zone implantée et permet le report de la fine couche monocristalline. L’objet de cette thèse est d’étudier l’aspect dynamique de cette étape de fracture.Pour ce faire, la vitesse de rupture et la déformation des plaques à l’arrière du front de fracture ont tout d’abord été mesurées à l’aide d’un montage optique original qui a ensuite été étendu aux études sur plaque entière 300mm. Ces données ont ensuite été modélisées. Dans un deuxième temps, l’interaction entre le front de fracture et des ondes acoustiques émises dynamiquement au cours de sa propagation a été étudiée. Celle-ci conduit à l’apparition récurrente d’un motif périodique sur le faciès de rupture qui consiste en une très faible variation de rugosité sur de très grandes périodes (mm). Des mesures expérimentales permettent tout d’abord de mettre en évidence cette émission acoustique et d’étudier ses caractéristiques. La modélisation physique du phénomène puis sa simulation numérique permettent ensuite de retrouver la forme typique de ce motif. Enfin, des solutions technologiques sont proposées pour empêcher son apparition sur le faciès de rupture des plaques SOI
The Smart Cut™ technology is a generic way of transferring very thin layers of crystalline material onto a mechanical substrate. It is currently the industrial standard for Silicon On Insulator (SOI) manufacturing. The implantation of relatively high doses of gas ions in a thermally oxidized silicon substrate leads to the formation of a buried weakened layer in the crystal. The implanted wafer is then bonded onto a host substrate using direct wafer bonding. Under annealing, the implanted species evolve into microcracks lying parallel to the surface, and a controlled fracture process finally occurs along the implanted layer. The aim of this thesis is to study the dynamics of this fracture step.First of all, the fracture velocity and the deformation profile behind the crack tip have been measured using an original optical setup, which has been extended to full wafer studies. A model has been established to explain these data. Then, the interaction of the fracture front with self-generated acoustic waves has been studied. This interaction leads to the appearance of a macroscopic periodic pattern on post-split SOI wafers which is made of small variations of the SOI roughness on very large periods (mm). Experimental studies are first carried out to look at the fracture acoustic emission for different experimental conditions. Numerical simulations based on acoustic phase calculations are then performed to recover the typical pattern shape, with results consistent with experimental data. Finally, technologic solutions are proposed to prevent the pattern formation on the post-split SOI wafers

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Delcor, Laurianne. "Contribution à la modélisation du confort vibratoire et acoustique sous excitations multi-harmoniques en cabine d’hélicoptères". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI042.

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Les hélicoptères sont des machines complexes générant une quantité importante de bruit et de vibrations. Il est donc important pour Airbus de savoir en spécifier l’inconfort pour proposer des hélicoptères confortables à leurs clients. La littérature propose une norme pour quantifier le confort vibratoire à partir de mesures d’accélérations (ISO2631-1). Concernant le bruit, des études internes à Airbus ont été réalisées et ont montré que l’inconfort sonore pouvait être modélisé par une fonction de la sonie, de l’acuité, de la tonalité et du niveau en dB(G). Enfin, il n’existe pas de modèle d’inconfort global liant l’inconfort de stimuli sonores et vibratoires simultanés, pour une application à l’hélicoptère. Cette thèse vise à modéliser l’inconfort global en se basant sur ces outils. Plusieurs expériences perceptives visant à faire évaluer l’inconfort de stimuli vibratoires à des volontaires ont été réalisées. Elles ont montré que la norme ISO2631-1 fournit une bonne estimation de l’inconfort vibratoire. Une modification de cette norme prenant en compte la modulation d’amplitude des accélérations permet d’améliorer la qualité prédictive dans le cas de phénomènes de battements. Des expériences similaires ont été réalisées en acoustique, où des participants ont évalué des stimuli sonores sans et avec protections auditives. Dans le premier cas, le modèle d’inconfort développé par Airbus reste valable. Un modèle plus simple basé sur la sonie uniquement permet une meilleure estimation de l’inconfort sonore. Avec protections auditives, l’estimation de l’inconfort n’est pas aussi directe, il faut au préalable filtrer les signaux sonores par les atténuations des protecteurs. Cette thèse a montré que pour des sons d’hélicoptères, les valeurs d’atténuations fournies par les constructeurs sont trop optimistes. Des mesures objectives d’atténuations donnent des valeurs plus faibles, en accord avec les préconisations de l’INRS. Les signaux sonores sont donc filtrés par les atténuations des protecteurs fournies par les constructeurs pénalisées selon l’INRS. Un modèle à partir de la sonie seule permet d’estimer l’inconfort sonore sous protections auditives. Toutefois, les coefficients de ce modèle sont différents du modèle obtenu pour une écoute sans protections. Enfin, des volontaires ont estimé l’inconfort global pour du bruit et des vibrations d’hélicoptères joués simultanément. Les résultats ont montré qu’un modèle d’inconfort global peut être obtenu à partir des indicateurs d’inconfort sonore et des indicateurs d’inconfort vibratoire. Ce modèle est basé sur une régression linéaire à laquelle un terme de couplage a été ajouté, sous la forme de la valeur absolue de la différence entre l’indicateur sonore et l’indicateur vibratoire. Un modèle simplifié permet de s’affranchir des mesures vibratoires à l’assise et au dossier et permet d’estimer l’inconfort à partir de mesures de bruit et d’accélérations aux pieds, pour un siège donné
Helicopters are complex machines generating a significant amount of noise and vibration. It is therefore important for Airbus to be able to specify the discomfort to offer comfortable helicopters to their customers. The literature proposes a standard to quantify vibration comfort from acceleration measurements (ISO2631-1). Concerning noise, internal Airbus studies have been carried out and have shown that noise discomfort can be modelled as a function of loudness, acuity, tone and level in dB(G). Finally, there is no overall discomfort model linking the discomfort of simultaneous sound and vibration stimuli for application to the helicopter. This thesis aims to model global discomfort based on these tools. Several perceptual experiments aimed at evaluating the discomfort of vibratory stimuli in volunteers have been performed. They have shown that the ISO2631-1 standard provides a good estimate of vibratory discomfort. A modification of this standard taking into account the amplitude modulation of accelerations makes it possible to improve the predictive quality in the case of beating phenomena. Similar experiments have been performed in acoustics, where participants evaluated sound stimuli without and with hearing protection. In the first case, the discomfort model developed by Airbus remains valid. A simpler model based on loudness alone allows a better estimation of the sound discomfort. With hearing protectors, the estimation of discomfort is not as direct, the sound signals must first be filtered out by the attenuation of the protectors. This thesis has shown that for helicopter sounds, the attenuation values provided by the manufacturers are too optimistic. Objective attenuation measurements give lower values, in accordance with INRS recommendations. The sound signals are therefore filtered by the attenuations of the protectors provided by the manufacturers penalized according to the INRS. A model based on loudness alone makes it possible to estimate the sound discomfort under hearing protection. However, the coefficients of this model are different from the model obtained for listening without protection. Finally, volunteers estimated the global discomfort for noise and vibrations of helicopters played simultaneously. The results showed that a global discomfort model can be obtained from the noise discomfort indicators and the vibration discomfort indicators. This model is based on a linear regression to which a coupling term was added, in the form of the absolute value of the difference between the noise indicator and the vibration indicator. A simplified model makes it possible to dispense with vibration measurements at the seat and backrest and to estimate discomfort from noise measurements and foot accelerations for a given seat

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Jelínek, Ondřej. "Vliv vzduchotechnických zařízení na akustické mikroklima čistých prostorů". Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-355617.

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The work description is to create a system of measures to prevent the spread and the consequent attenuation of sound in air handling systems serving the cleanrooms. The thesis presents a solution to noise attenuation in the investigated area, and in HVAC duct, which uses a commercially available material in the form of sound insulation hoses. In the systém solution is part of the work focuses on the optimal design of terminal elements to distribute air in a clean room. Processing methods utilize theoretical and experimental approach. The experiment comprises a unique analysis of the sound insulation properties of selected products under specific conditions. The data obtained are analyzed and incorporated into the framework of this work created program module for determining the attenuation and noise propagation in an enclosed space. Math and physical dependence are programmed into their own DLL by programming language DELPHI.

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Trojáková, Michaela. "Penzion Pamferova Huť". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372261.

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This diploma thesis describes the design and processing of project documentation pension. The proposed facility is located in the village of Železná Ruda- Pamferova Hut. The site is widely used by tourists in winter and summer. This is partly basement building, which has 2 storeys and an attic. The roof is designed as a gabled dormer with a flat roof. The building is based on the footings of plain concrete and under the reinforced concrete pillars are designed shoe. Supporting, peripheral and partition walls are designed from sand-lime bricks SENDWIX. An exception is peripheral walls of the basement, which is in contact with soil, which is designed as a lost formwork. In the dining area, which has an open reinforced concrete columns. Ceiling structure will consist of prestressed ceiling panels SPIROLL. Perimeter walls are insulated using external thermal insulation composite system using insulation from stone wool. The building is functionally divided into three main parts with a common main entrance. The first part is a restaurant with a kitchen, storage and kitchen facilities. This section is designed restaurants with a total capacity of 26 persons, the capacity will be in the summer to expand the possible capacity of the terrace, which belongs to the dining room. It is also proposed sanitary facilities for visitors to the restaurant, kitchen with storage and facilities for staff. The second part is the wellness center, which consists of a gym and rooms with infrared sauna and whirlpool. This section is designed sanitary facilities for visitors separated for men and women. The last part of the pension, which used to accommodate 30 people and the background of the pension. Backgrounds pension means any technical equipment room, storage room for bikes and skis, and not least the individual room house, which also includes a room for personal hygiene. This thesis was created with an emphasis on a correct layout and architectural design, static requirements an

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Yves, Simon. "Métamatériaux cristallins : du motif sub-longueur d'onde au comportement macroscopique". Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC226.

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Les matériaux tirent beaucoup de leurs propriétés de l'interaction entre leurs constituants et une onde. Ceci est principalement conditionné par deux caractéristiques: la composition et l'arrangement structurel. Cette interdépendance est précisément décrite par la physique du solide. Ceci a ensuite motivé la découverte des matériaux composites dont les caractéristiques découlent à nouveau de ces deux critères. Ils se divisent en deux catégories. La première est celle des cristaux photoniques/phononiques, qui tirent leurs propriétés de leur arrangement périodique. La seconde catégorie est celle des métamatériaux, dont les propriétés proviennent de l'interaction de leurs constituants avec les ondes. Les effets de structure sont généralement négligés dans la description de ces milieux et ils sont considérés comme étant des milieux homogènes avec des paramètres effectifs. Ces deux types de systèmes semblent donc a priori très différents du point de vue de l'interaction avec les ondes. Dans cette thèse, nous nous intéressons au cas des métamatériaux localement résonant, c'est-à-dire à ceux dont la cellule unité est un résonateur sub-longueur d'onde. Au lieu de les considérer comme des milieux homogènes effectifs, l'idée est de partir des caractéristiques de la cellule unité du milieu ainsi que de son arrangement spatial afin d'obtenir ses propriétés macroscopiques. Cette approche microscopique permet d'appréhender conjointement les effets de structure et de composition. Ceci est décrit dans le chapitre I, où nous introduisons le concept de polariton dont la relation de dispersion présente une bande liée à des modes sub-longueur d’onde, et une bande interdite d’hybridation. Dans le chapitre II, nous tirons parti cette dernière afin d’induire un couplage localisé entre des défauts résonants qui est similaire au terme de saut que l'on retrouve au sein des Hamiltoniens tight-binding de physique du solide. Nous reproduisons ainsi les structures de bande du graphène et du réseau « dice », ce qui nous permet de mesurer des cônes de Dirac au sein du système. Dans le chapitre III, nous introduisons le concept des métamatériaux cristallins, ce qui revient à considérer ces milieux comme des cristaux photoniques/phononiques, mais à une échelle très petite devant la longueur d'onde de travail. Cela nous permet d’induire une bande négative dans le système mais aussi une bande relativement plate, et des cônes de Dirac. Dans le chapitre IV nous brisons ces cônes en réalisant un analogue de l’effet Hall quantique de Vallée, ce qui revient à modifier conjointement la structure et la composition de la cellule unité. Dans le chapitre V nous brisons encore une fois ces cônes afin de d’induire des propriétés topologiques dans le milieu et de créer un analogue macroscopique d’un isolant topologique de spin
Many material properties arise from the interaction between their constituents and a wave. This is mainly conditioned by two characteristics: the composition and the structural arrangement. This interdependence is precisely described by condensed matter physics. This motivated the discovery of composite materials whose characteristics also stem from these two criteria. They divide in two categories. The first is the photonic/phononic crystals, whose properties are linked to their periodic arrangement. The second category is the one of metamaterials, whose properties come from the interaction of their constituents with the waves. The structural effects are generally neglected in the description of these media and they are considered to be homogeneous media with effective parameters. These two types of systems seem very different from the point of view of the interaction with the waves. In this thesis, we focus on locally resonant metamaterials, whose unit cell is a sub-wavelength resonator. Instead of seeing them as effective homogeneous media, the idea is to start from the characteristics of the unit cell of the medium as well as from its spatial arrangement in order to obtain its macroscopic properties. This microscopic approach makes it possible to jointly apprehend the effects of structure and composition. This is described in Chapter I, where we introduce the concept of polariton whose dispersion relation has a band linked to subwavelength modes, and a hybridization bandgap. In Chapter II, we use the latter to induce a localized coupling between resonant defects that is similar to the hopping term found in tight-binding solid-state physics Hamiltonians. We reproduce the band structures of graphene and of the dice lattice, which allows us to measure Dirac cones within the system. In Chapter III, we introduce the concept of crystalline metamaterials, which amounts to seeing these media as photonic/phononic crystals, but on a very small scale compare to the operating wavelength. This allows us to induce a negative band in the system but also a relatively flat band, and Dirac cones. In Chapter IV we break these cones by creating an analogue of the quantum Hall effect of Valley, which amounts to jointly modifying the structure and composition of the unit cell. In Chapter V we again break these cones in order to induce topological properties in the medium and to create a macroscopic analogue of a topological isolator

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Piquemal, Philippe. "Élaboration d'un nouveau matériau isolant phonique et thermique en verre expansé et mise au point d'un procédé utilisant un chauffage diélectrique". Nancy 1, 1988. http://www.theses.fr/1988NAN10203.

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On cherche à fabriquer un matériau en verre expansé (foamglass) ayant une bonne absorption acoustique à l'aide d'un processus d'expansion faisant appel au chauffage mixte diélectrique et infra-rouge. Deux types de matériaux à cellules ouvertes (petites bulles ou grandes bulles) sont conçus au laboratoire. On suit l'absorption aux moyennes et hautes fréquences (microondes). L'apport d'énergie électromagnétique au cours du chauffage infra-rouge favorisé l'expansion du matériau, alors que les microondes sont peu satisfaisantes

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Soussi, Chaima. "Développement de modèles numériques pour l'évaluation des performances vibro-acoustiques de fenêtres en basse fréquence". Thesis, Paris, HESAM, 2020. http://www.theses.fr/2020HESAC014.

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Les travaux de cette thèse portent sur la prédiction numérique de la transmission acoustique de doubles vitrages isolants et de fenêtres en menuiserie bois dans le domaine des basses fréquences. Dans ce cadre, pour la résolution du problème multiphysique, la méthode des éléments finis est utilisée. Ce choix est justifié par le fait que cette approche est adaptée à la résolution des problèmes d'interaction fluide-structure en basse fréquence, grâce notamment à sa souplesse dans la prise en compte du couplage entre domaines et des complexités géométriques et matérielles des structures. Pour atteindre l'objectif visé, des analyses modales expérimentales des principaux composants d'une fenêtre, puis d'une fenêtre complète, sont réalisées afin de recaler les différents modèles numériques. De plus, l'effet des conditions expérimentales sur la mesure de l'indice d'affaiblissement acoustique est analysé au travers de la définition de quatre configurations numériques de l'essai acoustique en laboratoire. Ces configurations, dont la différence est liée à la représentation des salles d'émission et de réception, permettent de caractériser leur influence sur la détermination de l'indice d'affaiblissement acoustique en dessous de la fréquence de Shroeder. Les résultats numériques, obtenus avec une configuration en champ libre pour des doubles vitrages et des fenêtres, sont comparés à des résultats expérimentaux pour évaluer l'efficacité et la validité des modèles développés. Enfin, des études paramétriques sont menées pour étudier l'influence sur l'indice d'affaiblissement acoustique de certains paramètres tels que (i) les propriétés des vitres ou du système d'étanchéité, (ii) les caractéristiques de la cavité inter-vitrage, et (iii) les conditions aux limites
This doctoral thesis focuses on the numerical prediction of the sound transmission of insulating double glazing and wooden windows in the low frequency range. In this context, the finite element method is used to solve the multiphysical problem. This choice is justified by the fact that this approach is suitable for the resolution of fluid-structure interaction problems in low frequencies, due in particular to its flexibility in taking into account the coupling between domains and the geometrical and material complexities of the structures. To reach the desired objective, experimental modal analyses of the main components of a window, and then of a complete window, are performed in order to calibrate the numerical models. In addition, the effect of experimental conditions on the measurement of the sound transmission loss is analysed through the definition of four numerical configurations of the acoustic laboratory test. These configurations, whose difference is linked to the representation of the emitting and receiving chambers, allow to highlight their influence on the determination of the transmission loss below the Shroeder frequency. The numerical results, obtained with a free-field configuration for double glazing and windows, are compared to experimental results to evaluate the efficiency and validity of the developed models. Finally, parametric studies are carried out to investigate the influence on the sound transmission loss of some parameters such as (i) the properties of the glazing or sealing system, (ii) the characteristics of the inter-glazing cavity, and (iii) the boundary conditions

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Eisel, Thomas. "Cooling of electrically insulated high voltage electrodes down to 30 mK". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-77442.

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The Antimatter Experiment: Gravity, Interferometry, Spectroscopy (AEGIS) at the European Organization for Nuclear Research (CERN) is an experiment investigating the influence of earth’s gravitational force upon antimatter. To perform precise measurements the antimatter needs to be cooled to a temperature of 100 mK. This will be done in a Penning trap, formed by several electrodes, which are charged with several kV and have to be individually electrically insulated. The trap is thermally linked to a mixing chamber of a 3He-4He dilution refrigerator. Two link designs are examined, the Rod design and the Sandwich design. The Rod design electrically connects a single electrode with a heat exchanger, immersed in the helium of the mixing chamber, by a copper pin. An alumina ring and the helium electrically insulate the Rod design. The Sandwich uses an electrically insulating sapphire plate sandwiched between the electrode and the mixing chamber. Indium layers on the sapphire plate are applied to improve the thermal contact. Four differently prepared test Sandwiches are investigated. They differ in the sapphire surface roughness and in the application method of the indium layers. Measurements with static and sinusoidal heat loads are performed to uncover the behavior of the thermal boundary resistances. The thermal total resistance of the best Sandwich shows a temperature dependency of T-2,64 and is significantly lower, with roughly 30 cm2K4/W at 50 mK, than experimental data found in the literature. The estimated thermal boundary resistance between indium and sapphire agrees very well with the value of the acoustic mismatch theory at low temperatures. In both designs, homemade heat exchangers are integrated to transfer the heat to the cold helium. These heat exchangers are based on sintered structures to increase the heat transferring surface and to overcome the significant influence of the thermal resistance (Kapitza resistance). The heat exchangers are optimized concerning the adherence of the sinter to the substrate and its sinter height, e.g. its thermal penetration length. Ruthenium oxide metallic resistors (RuO2) are used as temperature sensors for the investigations. They consist of various materials, which affect the reproducibility. The sensor conditioning and the resulting good reproducibility is discussed as well.

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Svoboda, Jan. "Sportovní centrum Polička". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240241.

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This thesis deals with the design and elaboration process of a project documentation of a sports centre. The designed sports centre building is situated in the southern part of the town of Polička, in the area determined for sports and free time activities complexes and areas. It is a two-floor, non-cellar, flat-roof building. It is based on plain concrete strip foundations and reinforced concrete foundation footing. The bearing, peripheral and partition walls are designed from POROTHERM hollow clay blocks. Reinforced concrete columns are designated in open disposition areas. The ceiling construction is made from SPIROLL pre-stressed concrete floor slabs and point-supported reinforced concrete slabs. The peripheral walls of the first aboveground floor are insulated with external thermal insulation system with a protective gabion facade. The peripheral wall thermal insulation in a bowling restaurant and gym halls extension is designed from a ventilated facade with CEMBRIT METRO facade cladding panels. The building is functionally divided into two main parts with a shared entrance. The sports centre with gyms and other sports facilities form the first part. Three squash courts, a mini-football piste, a special room for spinning and alpinning, a room for group exercising and cloakrooms with sanitary facilities are designed within one part of the sports centre. A restaurant with a bowling area and a kitchen with storerooms and other facilities for employees form the second part. The designed complex is barrier-free. There is aimed to be a car park for fifty cars, four motorbikes and a bus in front of the building. Three parking places are for disabled people.

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Kolesa, Jiří. "Polyfunkční dům ve Strakonicích". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265574.

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The subject of this thesis is the design and project documentation of a new multifunctional house in Strakonice. The building has four floors, without basement, and is located on a slightly sloping land in the suburban part of the town of Strakonice. It is based on shallow foundations and covered with a flat roof. It is a transverse wall structural system, build with clay block masonry, with the semi-assembled ceiling structures of ceramic and concrete beams and inserts. It is conceived as a double-aisle layout. The ground floor of each wing consists of the establishment of shops and house facilities. The overground floors are designed as six residential units of varying size category. Both tracts have separate entrances to both the residential portion and to individual businesses. The building is designed from traditional building materials. In addition to the architectural construction and civil-engineering design, a part of this project is also a fire safety design and an assessment from the perspective of building physics.

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Chiang, Chung-Lien, i 江宗璉. "The Experiment and Calculation of Acoustical Insulation Properties for Multi-Layers Complex Material Plates". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/57730457234930182060.

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碩士
國立臺灣海洋大學
系統工程暨造船學系
103
This article is to study the current common market of the plate, such as calcium silicate board, gypsum board, fiber cement board composed of light steel partition walls. We take interactive experiments and numerical acoustics software verification with the different materials groups. The single-layer board and multi-layer board transmission loss value of its performance are collated, with acoustic software analysis to identify excellent group of light partition walls. We also dig holes of the plate to change the structural properties and research the plate transmission loss value. The results show that can improve the insulation effects.

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LUO, WU-MING, i 羅武銘. "Research on the acoustical enriroment control of residence:the evaluation on insulation performance of floor impact sound of housing in Taiwan area". Thesis, 1991. http://ndltd.ncl.edu.tw/handle/52787363743862911979.

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WANG-WEI i 王為. "Research on the acoustical environment control of architecture:the evaluation on sound insulation effect of light-weight partition walls by sound intensity method". Thesis, 1990. http://ndltd.ncl.edu.tw/handle/73764707042037900099.

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Chung, Wen, i 鍾文. "The Automatic Measurement Analysis for Sound Insulation of Acoustic Materials". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/49460939870975383497.

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碩士
國立臺灣海洋大學
系統工程暨造船學系
100
This thesis is to design an automatic sound insulation measurement system, and compare with artificial intensity set. The design of automatic sound insulation measurement system is use the step motor to drive and PLC(Programmable Logic Controller)for programming and control. Compare with two ways of experiment in same number of measure points and same material, to find out what was the cause of the errors and improve it to achieve completely automatic control.

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Benkreira, Hadj, Amir Khan i Kirill V. Horoshenkov. "Sustainable acoustic and thermal insulation materials from elastomeric waste residues". 2011. http://hdl.handle.net/10454/9042.

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This study presents the data elements to develop a new processing route to transform elastomeric waste residue (particulates) into acoustic and thermal insulation materials that can compete with commercial products. The approach is to bind these grain and fibre particulates with a foaming polyurethane or a similar polymer, the chemistry of which can be manipulated to control the structure stiffness and the evolution of the foaming gas into open or closed cells. Here the study uses two examples of such residues, tyre and carpet shreds both composed of fibres trapping grains of either rubber or PVC. Compounds were made from these systems with different PU binders and the structural properties (density, porosity, air flow resistivity, tortuosity and stiffness) and performance properties (sound absorption, sound transmission, impact sound insulation and thermal conductivity) were measured as a function of binder loading and chemistry. The data obtained show clearly that performance can be tailored by tailoring structural properties resulting with materials that match or even outperform commercial products. The data set obtained here can be usefully exploited with available acoustic and thermal insulation materials model to take the approach further and extended to other waste systems.

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