Orientador: Stelamaris Rolla Bertoli / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-18T02:20:34Z (GMT). No. of bitstreams: 1 Santos_Christiandos_D.pdf: 4395219 bytes, checksum: 4831a94f1fac3d48f614220d1ce8659e (MD5) Previous issue date: 2011 / Resumo: A ambientação acústica de salas é um tópico muito importante nos espaços contemporâneos, principalmente quando considerada a tendência de utilização para várias finalidades. A adaptação do ambiente de acordo com o uso em questão é realizada a partir da alteração do direcionamento da energia sonora dentro deste ambiente. Esta redistribuição pode seguir certas linhas de acordo com o projeto ou da utilização do espaço como música, fala e palestras. Parâmetros que representam quantitativamente a percepção sonora de um ambiente podem ser obtidos pela resposta impulsiva deste ambiente. Estes parâmetros descrevem um certo "panorama acústico", que demonstra as características da sala para a percepção auditiva. A partir das respostas impulsivas de um ambiente e com a técnica de auralização de sinais é possível obter um panorama acústico a partir de um sinal sem impressão espacial sonora. Esta simulação é possível utilizando-se, dentre outros parâmetros, o coeficiente de espalhamento das superfícies determinado a partir da norma ISO 17497:2004. O efeito do coeficiente de espalhamento obtido experimentalmente e utilizado em simulações computacionais para fins de auralização é o objeto de estudo deste trabalho. Para a avaliação deste efeito foram realizadas medições de coeficiente de espalhamento de superfícies utilizadas em modelo computacional e superfícies difusoras. Estes valores foram utilizados em simulações de salas para criar panoramas de estudo. Com a auralização de sinais com estes panoramas um teste de júri foi realizado, observando condições de alteração de localização do espalhamento e de quantidade de espalhamento em uma sala virtual projetada para música. Os efeitos destas alterações nos atributos de Clareza, Lateralização, Reverberância, Razão de Baixos e Brilho foram analisados em uma sala modelada para uma boa audição de música. Os coeficientes de espalhamento produzem uma percepção maior da Clareza quando os difusores estão próximos da fonte sonora ou do receptor. Quando analisado o aumento do valor do coeficiente de espalhamento em paredes laterais entre fonte e receptor, estes fatores não produziram um resultado definido. A reverberância é percebida quando colocadas superfícies difusoras nas paredes entre fonte e receptor e quando colocadas superfícies difusoras próximas ao receptor. O fator de Razão de Graves não produziu efeito perceptivo quando os difusores foram colocados próximos à fonte e ao receptor, mas observou-se uma certa percepção deste parâmetro quando se aumentou o valor do espalhamento para as laterais entre o receptor e a fonte sonora. A lateralização é mais percebida quando colocadas superfícies difusoras entre fonte e receptor, porém com o aumento do valor do espalhamento ela passa a ficar pouco percebida. A partir dos atributos analisados pode-se verificar que o coeficiente de espalhamento cria um aumento da energia das primeiras reflexões que são percebidas dependendo da posição e do parâmetro que se deseja reforçar. Quando o coeficiente de espalhamento nas paredes laterais entre ouvinte e fonte sonora foi aumentado, a auralização criou uma sensação reverberante maior, o que diminuiu a percepção de certos atributos subjetivos, como a Lateralização, a Clareza e a Reverberância / Abstract: The Study of room acoustics characteristics is an important topic in the contemporary multiuse spaces. The acoustical perception can be changed with the redistribution of the acoustic energy. This redistribution can follow some necessity of the project or by the use. With the Impulsive Response measurement of a space is possible to quantify some acoustics parameters that are responsible for the acoustic perception in this space. These parameters can create a kind of "acoustic panorama" that shows the room characteristics for the acoustic subject perception. With these panoramas and the auralization technique is possible to simulate a room impression. For this simulation the scattering coefficient determined by ISO 17497:2004 is used. This work has the objective of analyze the effect of the scattering coefficient obtained experimentally in the subject perception using subjective parameters for room quality classification. For this effect evaluation some scattering coefficient determination was done for some surfaces. Some panoramas were changed according to the scattering coefficient measured and these panoramas were showed for the subjects to evaluate their response of these variations. The influence of the scattering coefficient in the subject perception was studied and the variations were measure using the room quality parameters. The subject's answers showed some variations on the perception and the results showed influence at the parameters of Clarity, Lateralization, Reverberance, Bass Ratio and Brilliance. The scattering coefficient increase the sensation of Clarity with some of then putted near the source and near the listener. With the increase of the scattering coefficient at the side walls in the room the listeners lose the Clarity sensation. The reverberance is perceived when are scattering coefficients at the side walls between source and receiver and near the receiver. The Bass Ratio was unperceived when the scattering coefficient was placed near the source and the receiver, but it was perceived when the scattering coefficient was placed between the source and receiver on the side walls. The lateralization was perceived when the scattering coefficient was placed between the source and receiver on the side walls, but if there is an increase of these scattering coefficients a decrease of the lateralization perception is perceived. Based on the analyzed parameters the scattering coefficients increase the energy in the early part of the Impulsive Response it depends on the place and the perceived parameter that was verified. With the increase of the scattering coefficient on the side walls between the source and the receiver the auralization decrease the sensation of some parameters like Clarity, Lateralization and Reverberance / Doutorado / Arquitetura e Construção / Doutor em Engenharia Civil

Orientador: Ivone Panhoca / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-06T19:21:56Z (GMT). No. of bitstreams: 1 Guimaraes_MichelleFerreira_M.pdf: 3257210 bytes, checksum: b0cb64faae1ee6b05d701f96bebce7c0 (MD5) Previous issue date: 2006 / Resumo: A voz e a habilidade vocal são diferentes em cada indivíduo. Devido aos escassos estudos sobre a qualidade vocal de adolescentes durante a puberdade, o presente estudo tem como objetivo identificar os seguintes parâmetros da análise acústica da voz: freqüência fundamental, seus índices de perturbação a curto prazo {jitter e shimmer), proporção GNE (glottal noise excitation), ruído, semitons e intensidade; correlacioná-los entre e si e também com o grau do desenvolvimento puberal de adolescentes do sexo masculino. Métodos: Foram sujeitos desse estudo 46 adolescentes do sexo masculino, com idade entre ] 3 e 15 anos, estudantes de uma escola estadual de Campinas, onde foi feita a coleta dos dados. Os adolescentes foram submetidos à gravação da voz, em gravador digital. Solicitou-se emissão sustentada da vogal /s/ e fala encadeada: contagem de 1 a 10, emissão dos meses do ano e leitura de um trecho pré-estabelecido. Em seguida foram avaliados por uma médica pediátrica para caracterização do grau do desenvolvimento puberal de acordo com os estágios descritos por Tanner (G1 a G5). A análise vocal foi realizada com o programa acústico Voz Metria®. Resultados: A maioria dos adolescentes está entre G3 e GA, a freqüência fundamental média é de 261,5Hz e todos apresentaram freqüência fundamental acima de 200Hz. Jitter manteve-se com média de 0,26% (dentro dos padrões de normalidade). Shimmer mostrou-se alterado em 38 dos 46 indivíduos, apresentando média de 8,41%, considerado acima do limite de normalidade. A proporção GNE e ruído estão dentro dos limites de normalidade para todos os adolescentes, porém todos apresentaram quantidade de semitons acima do esperado. A freqüência fundamental é mais aguda em G4 e G5 (p=0,003), shimmer é alterado em freqüências mais agudas (p=0,008). Conclusão: Os adolescentes estudados possuem freqüência fundamental de característica infantil e feminina, apesar de estarem no início do desenvolvimento puberal adulto, além disso, a maioria deles apresentou shimmer alterado. A maturação da voz provavelmente ocorre após a maturação do desenvolvimento puberal / Abstract: Voice and voice ability are different in each person. Due to scarce studies about adolescents' voice, this study purpose to correlate voice fundamental frequency and its quotients of perturbation at short terra (jitter and shimmer), GNE (glottal noise excitation) values, half-tone, present noise, intensity and the degree of puberty development in male teenagers. Methods: It is a transversal study with 46 boys, with age varying from 13 to 15 years, students from a public school in Campinas (Brazil), where the study was performed. The adolescent's voices were recorded in digital recorder and the speech samples consisted of the vowel /e/ in sustained phonation, counting (from 1 to 10), saying the months of the year and reading. Afterwards, the pediatrician evaluated and characterized the puberty development according to the Tanner stages. The vocal analysis was made in Vox Metria® acoustic programmer. Results: Most of the boys were in G3 and G4 Tanner stages, the mean of fundamental frequency was 261.5Hz and all the adolescents had FO > 200Hz. The mean of jitter was 0.26%, showing it was at normality standard. Shimmer was increased in 38 of 46 boys, which mean was 8.41%. The values of GNE and noise were in the normality limit; nevertheless the half-tones were above the standard. The fundamental frequency was high-pitched in boys with G4 e G5 (p=0,003) and shimmer was increased in high-pitched (p=0,008). Conclusion: These boys have fundamental frequency with childish and feminine characteristics although they are in the beginning of adult genitals development, most of they have alteration in shimmer values. Voice maturation probably occurs after pubertal maturation / Mestrado / Saude da Criança e do Adolescente / Mestre em Saude da Criança e do Adolescente

This thesis focuses on the analytical properties of the acoustic vibrations and applications of metallic nanoparticles. With regard to the analytical properties of the acoustic vibrations, we focus on nanoparticle acoustic resonance enhanced four-wave mixing (FWM) as an in situ characterization technique for characterizing nanoparticles’ shape, size, and size distribution. The nonlinear optical response of metallic nanoparticles is resonantly driven by the electrostriction force which couples to the acoustic vibrations of nanoparticles. Information about nanoparticles’ shape, size, and size distribution can be obtained by analyzing the resonant peak position and linewidth in the FWM signal which carries the information about the vibrational modes. We characterize different nanoparticle solutions of different materials, shapes, and sizes using this FWM technique. Information obtained from the FWM characterization agrees well with the scanning electron microscopic examination, indicating the FWM technique can serve as an in situ nanoparticle characterization tool. We also demonstrate the FWM technique can be used for monitoring nanoparticle growth in situ. iii With regard to the applications of metallic nanoparticles, we focus on quantification of an exogenous cancer biomarker Acetyl Amantadine using surface-enhanced Raman scattering (SERS). Raman spectroscopy can provide unique fingerprint information of molecules, which can be used as a chemical detection and identification technique. The intrinsically weak Raman signal caused by the small scattering cross section presents a barrier for trace chemical detection. Localized surface plasmon resonance of metallic nanoparticles can provide large local field enhancement, which can be utilized to enhance the intrinsically weak Raman signal. In order to achieve higher local field enhancement, we focus on using the gap structures formed between nanoparticles instead of using discrete nanoparticles. Molecules should locate within the hot spots of the gap structures to experience the largest enhancement. This requires that molecules should be extracted from volume onto the metallic surface. Based on these guidelines, two SERS platforms are designed using gold nanoparticles (nanorods and nanospheres) combined with different surface functionalization techniques. The performance of these two platforms are characterized by investigating the sensitivity and limit of detection (LOD). 16 ng/mL and 0.4 ng/mL LODs are achieved for nanorod and nanosphere platforms, respectively. / Graduate

No description available.

With the increase in the application of ultra-precision manufactured parts and the absence of much participation of researchers in ultra-high precision grinding of optical glasses which has a high rate of demand in the industries, it becomes imperative to garner a full understanding of the production of these precision optics using the above-listed technology. Single point inclined axes grinding configuration and Box-Behnken experimental design was developed and applied to the ultra-high precision grinding of BK7 glass. A high sampling acoustic emission monitoring system was implemented to monitor the process. The research tends to monitor the ultra-high precision grinding of BK7 glass using acoustic emission which has proven to be an effective sensing technique to monitor grinding processes. Response surface methodology was adopted to analyze the effect of the interaction between the machining parameters: feed, speed, depth of cut and the generated surface roughness. Furthermore, back propagation Artificial Neural Network was also implemented through careful feature extraction and selection process. The proposed models are aimed at creating a database guide to the ultra-high precision grinding of precision optics.

Experience shows that the noise and sound quality in vehicles are often a recurring criticism. The bodies of modern vehicles consist predominantly of thin sheets of metal. It is hard to prevent the excitation of bending vibrations and the subsequent emission of disturbing noise while driving. The noise spectrum in a car that can be heard by the driver is from ”latent roar” to ”chattering” noise of the body and engine. In automotive vehicles damped materials, especially plastics or materials made from sheet metal and surface damping treatments, are used. Those have high internal energy losses and damp sound oscillatory systems found in the body or interior of cars. A further advantage of such treated components is that they are applied to existing components working over wide temperature and frequency ranges. Many companies provide such ”sound-absorbing compounds”. The requirements for these damping materials are high temperature-resistance, water repellence, fuel and oil-resistance and good adhesion to the base material [17]. The acoustic properties, especially the damping of the plate vibrations through rubber are of interest. the question arises how can the damping coeficient of coated metal sheets can be measured and secondly, by how much the road noise is reduced when built-in sheets are coated with a known damped material. With the Oberst Bar Test Method (named after Dr. H. Oberst) the properties are determined of the internal damping materials that can be used to simulate mechanical constructions to determine damping of larger surfaces. This method describes a laboratory test procedure for measuring the mechanical properties of damped materials. A block diagram of the test system consisting of a damped material bonded to a vibrating cantilever steel bar is shown in figure 2.1. This method is useful for testing materials such as metals, enamels, ceramics, rubbers, plastics, reinforced epoxy matrices and wood. In addition to damping measurement, the test allows for the determination of the Young’s modulus E of the material. E is calculated from the resonance frequency of a given mode and from the physical constants of the bar. By associating the damping factor with the Young’s modulus, a complex quantity is defined which is called the Complex Modulus of Elasticity. Measurements of dynamic mechanical properties are also useful in the research on the molecular structure of materials.

No description available.

Acoustic instabilities in a combustion chamber arise due to the coupling of acoustic pressure with in-phase heat-release, and are characterized by large amplitude oscillations of one or more natural modes of combustor. Even though an array of studies, both theoretical and experimental, has been conducted by a number of authors in this field to extract the flame response, most of these are based on kinematic flame models. In this dissertation, an experimental study of a subsonic flame's intrinsic response to acoustic pressure perturbations is performed for the case of a tube closed at one end and the other end opened to the atmospheric conditions. Pressure fluctuations inside the tube are measured for hot and cold side flows, and their varying trend is explained. The frequencies obtained from Fourier transform analysis exhibit a strong dependence with the distance between the stabilized flame position and open end of the tube. For different values of flame position (xf ), the values of growth constant 's' are calculated from the pressure versus time data readings procured from acoustic pressure transducer and dominant frequencies are analyzed from windowed FFT of the same. The expression for obtaining response function from the measured pressure fluctuations has been derived from the 1-D linearized conservation equations. The undamped response function plot is obtained by adding the decay rates at different frequencies inside the tube to the corresponding growth rates. Finally, the effect of blockage of pre-mixed flow on the growth rates inside the tube and consequently, the flame response values, is studied by repeating the experiment with different types of flame holders. A large number of theoretical flame-response models have been developed in modern literature, and some of these models are compared with the experimentally obtained response. Suggestions are also cited in this study so as to account for the observed deviations in trends. This includes a revisit of the intrinsic flame model by incorporating the effect of flame-area perturbations, with the aid of analyzed steady flame images.

The influence of electronic percussion (in particular, the Simmons Drum Company’s innovations) on the compositions and evolution of 1980s Pop music can be examined through technological advancements as well as stylistic characteristics of drum partitions of the decade. Archived company catalogues in collaboration with Matt Dean’s historical timeline provide a clear understanding of the advancements during the time of the company’s tenure at the top of the electronic percussion industry. Definitions of the terms “style” and “genre” in both the primary and secondary approaches -by Allan Moore and other theorists- are used. The stylistic properties which create a genre are key in understanding the political, social, and cultural effects on the music. Ultimately, stylistic traits provide sufficient evidence in order to examine similar compositions which were sub-categorized differently on Billboard’s hit charts. Dave Carlton’s Hook Theory is a major resource in selecting pieces of music which share similarities. The differences in sub-categorization identified in this study are shown to derive from the transition to and the use of electronic percussion.

The overall objective of this thesis was to predict, model and measure low frequency acoustic backscatter from the sea surface zone (SSZ). In particular, the objectives were fourfold: to relate the acoustic backscatter Doppler spectrum to the directional waveheight spectrum (DWS) through a perturbation analysis; to develop instrumentation suitable for measuring the properties of acoustic backscatter from the SSZ; to design and implement signal processing hardware and software to process raw data from the instrument; and to deploy the instrument and make measurements to test the validity of the predictions of the theoretical development. A theoretical framework was developed to enable a test of the acoustic analogue of the Coastal Ocean Dynamics Applications Radar (CODAR) technique, using beamforming techniques to simulate the CODAR antennas. Expressions relating the CODAR antenna outputs to the output of an array of omnidirectional acoustic point sensors were developed, and mathematical algorithms and techniques were derived to extract information about the DWS of surface gravity waves from acoustic Doppler backscatter measurements with the array. Models were developed and implemented, showing the expected form of the power spectral density of the acoustic Doppler backscatter seen by single omnidirectional receivers, and the expected form of data products of the beamformed array. An acoustic instrument — the Upward-Looking Sonar Array System (ULSAS) — was developed for stand-alone, remotely controlled operation in both bottom-situated and deep-water, surface-tethered configurations. This device can collect and store large quantities of acoustic data from a multi-element array, under the control of a distant operator over a radio link. The bottom-situated version was deployed in the coastal waters of British Columbia, and the deep water version was deployed in the recent Surface Wave Processes (SWAPP) experiment. A preliminary test of the acoustic CODAR technique was made, yielding information consistent with the known wind and wave field. The form of the non-directional part of the extracted DWS followed approximately the expected k⁻⁴ shape for k values above saturation. Beamforming results using frequency-domain data show that the Doppler-shifted acoustic backscatter is directional in nature. These are the first results of this kind to be reported. The deep-water version of ULSAS was tested for the first time during the SWAPP cruise. In spite of a problem limiting the power output of the projector, estimates of the surface scattering strength parameter over angles of incidence less than 45° were made, showing some surprising departures from the Chapman-Harris empirical formula for S₅ , and interesting angular structure. Measurements of the ambient noise field were also made under calm conditions and during 14 kt winds. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate