O objeto deste texto é o ruído em sua relação com a música. Minha ideia é investigar, nem sempre num percurso linear, o papel que ele desempenha na música, especialmente no período que vai do início do século XX aos dias de hoje. Essa investigação não está voltada para um levantamento técnico, nem historicista do tema. Minha preocupação está mais voltada a uma camada mais profunda em que transparecem algumas conexões entre o que chamamos de pensamento musical e a própria cultura que engendra esse pensamento. O ruído é um elemento essencial para o entendimento de certos aspectos da Modernidade, especialmente no que diz respeito à produção musical (e porque não dizer, à produção das artes em geral) no período. O que pretendo mostrar é que muitas das contradições e tensões que alimentam a música moderna podem ser entendidas como movimentos em direção à aceitação ou rejeição do ruído. A ideia central deste texto é a de que existe um processo dialético recorrente na relação entre música e ruído. Como algo incômodo, marginal, o ruído tende a ser evitado, pois sempre traz o risco de desagregação de um sistema. Minha intenção é investigar a passagem do ruído, enquanto elemento desorganizador, para som quando incorporado na música. Essa relação se direciona a uma compreensão da maneira como o ruído, no século XX, tornou-se um elemento desestabilizador, instaurando uma tensão dialética entre sua rejeição e sua aceitação enquanto elemento musical. / The object of this research is the noise and its relationship with music. My idea is to investigate, not always through linear path, the role it plays in music, especially in the period from early twentieth century to now. This investigation is not focused on a technical survey, nor on an historicist approach to the theme. My concern is more focused on a deeper layer in which one can find some connections between what we call \"musical\" and the very culture that generates it. Noise is an essential element for the understanding of certain aspects of modernity, especially in respect of music production (and why not to say, of art production in general) in that period. What I want to show is that many of the contradictions and tensions that feed modern music can be understood as a movement toward acceptance or rejection of noise. The central idea of this text is that there is a recurring dialectical process in the relationship between music and noise. As a disturbance, as a marginal element, noise tends to be avoided, because it always brings the risk of desegregating a system. My intention is to investigate the passage from noise as a disruptive element to music. This relationship is directed to an understanding of how noise has become a destabilizing element, establishing a dialectic tension between its rejection and acceptance as a musical element.

Introdução. Pensar nos efeitos nocivos do ruído aos recém-nascidos (RN) com saúde debilitada se torna cada vez mais necessário devido aos avanços tecnológicos, ao aumento da sobrevida dos RNs de baixo peso, com maiores períodos de hospitalização. Objetivo geral. Avaliar os níveis de ruído das incubadoras das unidades neonatais de um hospital universitário de Ribeirão Preto, SP, em situações experimentais de manejo. Método. Trata-se de estudo quantitativo do tipo quase-experimental, realizado com 20 incubadoras das unidades neonatais de um hospital universitário de Ribeirão Preto, SP, que se encontravam disponíveis durante o período de coleta de dados. O período de coleta foi de agosto a setembro de 2008. As incubadoras foram divididas em três grupos (1, 2, 3), conforme a marca, o modelo, tempo de uso e situação de manejo. As medidas foram realizadas sem a presença do RN, em uma sala afastada do fluxo rotineiro das unidades neonatais. Foi utilizado um dosímetro, modelo Quest 400, com o microfone fixado dentro da incubadora para mensurar o Nível de Pressão Sonora (NPS). Foram realizadas as mensurações dos níveis de ruído contínuo (funcionamento do motor, alarme soando, pulso oxímetro e bomba de infusão sobre a cúpula e seus alarmes) e de impacto (manipulação da portinhola e ato de colocar o frasco de álcool gel sobre a cúpula) nas incubadoras. Os ruídos de impacto foram analisados nos modos de manipulação cuidadoso e brusco. As medidas com o pulso oxímetro, bomba de infusão e o ato de colocar o frasco de álcool gel sobre a cúpula foram repetidas com a presença do cueiro sobre a cúpula da incubadora. Os valores mensurados de Leq, Lmax, Lmin dos ruídos contínuos e os valores de Lpeak dos ruídos de impacto foram analisados por meio dos valores medianos, mínimos e máximos. Resultados. Os valores medianos gerais dos três grupos encontrados para ruído contínuos foram: Leq de 55,2dBA para ruído de funcionamento das incubadoras; Leq 65,5dBA de para alarme da incubadora; para pulso oxímetro e alarme e bomba de infusão e seu alarme os Leq foram: 54,7dBA, 58,4dBA, 53,9dBA e 66,1dBA NPS, respectivamente. Com cueiro, os valores nessas situações foram: 54,0dBA, 57,8dBA, 55,1dBA e 61,7dBA NPS, respectivamente. Todos Lmax medianos de cada grupo nas situações anteriormente descritas estiveram acima de 65dBA e os Lmin acima de 47dBA. Os ruídos de manipulação alcançaram valores de Lpeak medianos gerais para os três grupos de 91,2dBA e 97,9dBA NPS para abrir a portinhola nos modos cuidadoso e brusco e 91,5dBA e 109,5dBA NPS ao fechar cuidadoso e brusco a portinhola, respectivamente. Os níveis atingidos ao colocar o álcool gel sobre a cúpula no modo cuidadoso com e sem cueiro variaram de 89dBA a 89,6dBA NPS e no modo brusco com e sem cueiro de 107dBA a 107,7dBA. Conclusão. Os níveis gerados pelas incubadoras e seus alarmes estão abaixo daquele recomendado pelas normas nacionais, mas acima da norma internacional. A presença de equipamentos sobre a cúpula e seus alarmes soando não intensificaram os níveis de ruído nas incubadoras, com exceção do alarme da bomba de infusão. Os níveis de ruído produzidos pela manipulação da incubadora e o ato de colocar o álcool gel sobre a cúpula foram intensos e o modo cuidadoso foi um recurso para diminuir os níveis sonoros. De um modo geral, o uso do cueiro não reduziu o ruído gerado pelos equipamentos sobre a cúpula e nem o ruído gerado pelo ato de colocar o álcool gel sobre a cúpula. / Introduction. Technological advances and increase in survivorship of low birth weight newborns (NB), with longer periods of hospitalization, make each time more necessary to think about the noxious effects of noise to NB with weak health. Objective. to evaluate levels of noise in incubators of neonatal units in experimental handling situations, in a university hospital in Ribeirão Preto, state of São Paulo, Brazil. Method. Quantitative quasiexperimental study, carried out in 20 incubators in neonatal units during the data collection period, from August to September 2008, in a university-hospital in Ribeirão Preto, SP. Incubators were divided into three groups (1,2,3), according to brand, model, usage time and handling situation. Measuring occurred when NB were not in incubators, in a room far from usual neonatal unit routine work. A Quest 400 dosimeter with microphone fixed inside incubator was used to measure Sound Pressure Level (SPL). Levels of continuous noise (motors functioning, alarm sound, pulse oximeter and infusion bombs on the incubator dome and their alarms) and impact noise (manipulation of incubators door and putting the bottle of alcohol gel on the dome) in incubators were measured. Impact noises were analyzed for careful and rough manipulation. Measures with pulse oximeter, infusion bomb and putting the bottle of alcohol gel on the incubator dome were repeated with a swathe placed on the dome. Continuous noise Leq, Lmax, Lmin and impact noise Lpeak values measured were analyzed using mean, minimum and maximum values. Results. General mean values found for continuous noise in the three groups were: Leq intensity of 55,2dBA for incubators functioning noise; Leq 65,5dBA for incubators alarm; for pulse oximeter, alarm, infusion bomb and infusion bombs alarm Leq were: 54,7dBA, 58,4dBA, 53,9dBA and 66,1dBA SPL, respectively. Using a swathe, values in the same situations were: 54,0dBA, 57,8dBA, 55,1dBA and 61,7dBA SPL respectively. All mean Lmax for each group in the previously described situations were over 65dBA and Lmin over 47dBA. Manipulation noises reached Lpeak general mean values for the three groups of 91,2dBA and 97,9dBA SPL for rough and careful opening of incubator door, and 91,5dBA and 109,5dBA SPL for careful and rough closing, respectively. Levels reached for putting alcohol gel on the incubator dome carefully, with or without swathe, varied from 89dBC to 89,6dBC SPL, and roughly, with or without swathe, varied from 107dBC to 107,7dBC. Conclusion. Noise levels generated by incubators and alarms are under national rules, but over international rules. The presence of equipments on the dome and the sound of incubator alarm do not increase the levels of noise in incubators, with exception of infusion bombs alarm. Noise levels produced by incubator manipulation and putting alcohol gel on the incubator dome are intense, careful mode was a way to decrease noise levels. In a general way, the use of a swathe did not reduce noise generated by the equipments on the dome neither noise of putting alcohol gel on the dome.

Esse trabalho apresenta uma análise de dados dos níveis de ruído referentes à Subprefeitura de Pinheiros/SP. Foram feitas medições em quarenta pontos, divididas em três fases que puderam ser comparadas com os limites estabelecidos pela lei de zoneamento. Nos processos de levantamentos de dados elaboramos mapas que serviram de suporte tanto em decisões como posteriormente na análise/comparação destes em relação aos limites sonoros estabelecidos. Na primeira fase observou-se uma grande quantidade de pontos com valores acima de 15 dB em relação aos limites estabelecidos. Nas fases seguintes houve uma diminuição, quando comparadas a primeira. Assim obtivemos um panorama dos níveis de ruído da área de estudo e sua situação em relação à lei de zoneamento urbano da cidade de São Paulo. / This paper presents an analysis of data concerning the noise levels referring to Pinheiros Subprefecture (in São Paulo city). Measurements made in forty spots, divided in three steps that could be compared with the limits established by zoning law. In procedures for survey data were prepared maps that served as pillar in decisions as well as later in analysis/comparison of these in relation to the noise limits established. In the first phase there were large numbers of points with values above 15 dB above the limits. In later stages there was an improvement compared with the measurements of the first phase. So we got a picture of the noise levels of the study area and its situation in relation to the urban zoning law of São Paulo city.

In the design of voltage-controlled oscillators (VCOs) for communication systems, timing jitter is of major concern since it is the largest contributor to the bit-error rate. The latest deep submicron processes provide the possibility of higher oscillator speed at the cost of increased device noise and a higher 1/f noise corner. Therefore it is crucial to characterize the upconverted 1/f noise for practical applications. This dissertation presents a simple model to relate the time domain jitter and frequency domain phase noise in the presence of non-negligible 1/f noise sources. It will simplify the design, simulation, and testing of the PLL, since with this technique only the open loop VCO needs to be considered. Design methodologies for white noise dominated ring oscillators and PLLs are also developed by analyzing the upconverted thermal noise in time domain using a LTI model. The trade-off and relationship between jitter, speed, power dissipation and VCO geometry are evaluated for different applications. This model is supported by the measured data from 24 ring oscillators with different geometry fabricated in TSMC 0.18um process. The theory developed in this dissertation is applied to the design of PLL- and DLL- based true random number generators (TRNG) for application in the area of“smart cards". New architectures of dual-oscillator sampling and delay-line sampling are proposed for random number generation, which has the advantage of lower power dissipation and lower cost over traditional approaches. Both structures are implemented in test chips fabricated in AMI 1.5um process. The PLL-based TRNG passed the NIST SP800-22 statistical test suite and the DLL-based TRNG passed both the NIST SP800-22 statistical test suite and the Diehard battery of tests.

O ruído de baixa frequência é um limitador de desempenho em circuitos analógicos, digitais e de radiofrequência, introduzindo ruído de fase em osciladores e reduzindo a estabilidade de células SRAM, por exemplo. Transistores de efeito de campo de metalóxido- semicondutor (MOSFETs) são conhecidos pelos elevados níveis de ruído 1= f e telegráfico, cuja potência pode ser ordens de magnitude maior do que a observada para ruído térmico para frequências de até dezenas de kHz. Além disso, com o avanço da tecnologia, a frequência de corner —isto é, a frequência na qual as contribuições dos ruídos térmico e shot superam a contribuição do ruído 1= f — aumenta, tornando os ruídos 1= f e telegráfico os mecanismos dominantes de ruído na tecnologia CMOS para frequências de até centenas de MHz. Mais ainda, o ruído de baixa frequência em transistores nanométricos pode variar significativamente de dispositivo para dispositivo, o que torna a variabilidade de ruído um aspecto importante para tecnologias MOS modernas. Para assegurar o projeto adequado de circuitos do ponto de vista de ruído, é necessário, portanto, identificar os mecanismos fundamentais responsáveis pelo ruído de baixa frequência em MOSFETs e desenvolver modelos capazes de considerar as dependências do ruído com geometria, polarização e temperatura. Neste trabalho é proposta uma técnica para análise de ruído de baixa frequência baseada na autocorrelação dos espectros de ruído em função de parâmetros como frequência, polarização e temperatura. A metodologia apresentada revela informações importantes sobre os mecanismos responsáveis pelo ruído 1= f que são difíceis de obter de outras formas. As análises de correlação realizadas em três tecnologias CMOS comerciais (140 nm, 65 nm e 45 nm) fornecem evidências contundentes de que o ruído de baixa frequência em transistores MOS tipo-n e tipo-p é composto por um somatório de sinais telegráficos termicamente ativados. / Low-frequency noise (LFN) is a performance limiter for analog, digital and RF circuits, introducing phase noise in oscillators and reducing the stability of SRAM cells, for example. Metal-oxide-semiconductor field-effect-transistors (MOSFETs) are known for their particularly high 1= f and random telegraph noise levels, whose power may be orders of magnitude larger than thermal noise for frequencies up to dozens of kHz. With the technology scaling, the corner frequency — i.e. the frequency at which the contributions of thermal and shot noises to noise power overshadow that of the 1= f noise — is increased, making 1= f and random telegraph signal (RTS) the dominant noise mechanism in CMOS technologies for frequencies up to several MHz. Additionally, the LFN levels from device-to-device can vary several orders of magnitude in deeply-scaled devices, making LFN variability a major concern in advanced MOS technologies. Therefore, to assure proper circuit design in this scenario, it is necessary to identify the fundamental mechanisms responsible for MOSFET LFN, in order to provide accurate LFN models that account not only for the average noise power, but also for its variability and dependences on geometry, bias and temperature. In this work, a new variability-based LFN analysis technique is introduced, employing the autocorrelation of multiple LFN spectra in terms of parameters such as frequency, bias and temperature. This technique reveals information about the mechanisms responsible for the 1= f noise that is difficult to obtain otherwise. The correlation analyses performed on three different commercial mixed-signal CMOS technologies (140-nm, 65-nm and 40-nm) provide strong evidence that the LFN of both n- and p-type MOS transistors is primarily composed of the superposition of thermally activated random telegraph signals (RTS).

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Paola Crandall Fano. / M.S.

In this thesis we explore several topics with applications to both aero and hydroacoustics. Due to the much larger speed of sound in water compared to in air, several of the approximations used in aeroacoustics are not applicable underwater over the range of frequencies of interest. Specifically, we study the finite-chord effects on two broadband noise mechanisms: the trailing edge noise and the ingested noise problems. We start by investigating the acoustic wave diffraction by a finite rigid plate using three different methods. We compare the behaviour of the different solutions as a function of the reduced acoustic wavenumber. Our results reveal that the Mathieu function expansion is the most appropriate method as long as the reduced acoustic wavenumber is not too large. Finally, we show how the Mathieu functions can be used to build a Green's function tailored to an elliptic cylinder of arbitrary aspect ratio without relying on addition theorems. The results obtained in chapter two motivated the search for an exact solution to the trailing edge noise problem using a Mathieu function expansion. It is shown that the approximate methods used in aeroacoustics are not accurate enough for reduced acoustic wavenumbers less than unity, and for all wavenumbers near cut-off. Furthermore it is shown that, even at low Mach numbers, it is crucial to take into account the effects of convection at low frequency. Finally Lighthill's analogy is used, combined with the tailored Green's function introduced previously, to recover the two asymptotic Mach number scalings of the acoustic power for a flat plate at high frequency and low frequency. In chapter four, we introduce a novel method to solve the ingested noise problem by decomposing the pressure field into a singular part whose functional form can easily be found, and a regular part that we express using a Mathieu function expansion. It was found that finite-chord effects do have a strong impact for reduced acoustic wavenumbers less than unity, and for all wavenumbers near cut-off. The following chapter focuses on the trailing edge noise mechanism and details how the theory for a single stationary aerofoil can be applied to a rotating propeller. Due to the general geometry of a blade, we extended Amiet's model to take into account a mean flow misaligned with the blade chordline. Different semi-analytical models of wall pressure spectra are introduced and compared. We make extensive use of Brooks' data for a NACA 0012 aerofoil to obtain realistic inputs in the semi-analytical models. Finally, we introduce and compare two models of rotating blade trailing edge noise. The effects of both the angle of attack and the number of strips are then investigated. The final chapter is distinct from the rest of the thesis. We propose a model for studying the low Mach number flow noise from a 2D circular cylinder with small roughness. The method is based on using the Green's function tailored to a smooth cylinder in Curle's acoustic analogy. It was found that the main source of noise was the tonal low frequency scattering by the smooth geometry. However, it is suggested that roughness elements might be the dominant source of noise at higher frequency.

Thesis (M. Sc. (Nursing Science)) --University of Limpopo, 2017. / Refer to the document

One of the main criticisms of previously studied label noise models in the PAC-learning framework is the inability of such models to represent the noise in real world data. In this thesis, we study this problem by introducing a framework for modeling label noise and suggesting four new label noise models. We prove positive learnability results for these noise models in learning simple concept classes and discuss the difficulty of the problem of learning other interesting concept classes under these new models. In addition, we study the previous general learning algorithm, called the minimum pn-disagreement strategy, that is used to prove learnability results in the PAC-learning framework both in the absence and presence of noise. Because of limitations of the minimum pn-disagreement strategy, we propose a new general learning algorithm called the minimum nn-disagreement strategy. Finally, for both minimum pn-disagreement strategy and minimum nn-disagreement strategy, we investigate some properties of label noise models that provide sufficient conditions for the learnability of specific concept classes.

In this dissertation, a new signaling scheme known as Constant Voltage Power Transmission Line (CV-PTL) is presented to supply power to a digital I/O circuit. This signaling scheme provides power through a transmission line in place of a power plane while dynamically changing the impedance of the power delivery network to keep a constant voltage at the power pin of the IC. Consequently, this reduces the effects of return path discontinuities and can improve the quality of output signal by reducing power and ground bounce. Through theory, simulation, and measurements, we show that this new method can be used to reduce jitter and eye height with the proposed PDN methodology. In addition, the signaling scheme was extended to vertically-stacked 3D integrated circuits (3D ICs). It is known that power supply noise worsens as one goes higher up in the stack of dies due to increased interconnect inductance. However, by utilizing the CV-PTL concept in the PDN design of a 3-layer 3DIC system, the circuit showed considerable improvement in power supply noise and peak-to-peak jitter as compared to the conventional design approach. In addition to signal and power integrity of these signaling schemes, the noise coupling between digital and RF components is also investigated. A simple design for mitigating the coupling of power supply noise in mixed-signal electronics is presented. Currently used methods, such as electromagnetic bandgap structures have been shown to exhibit excellent noise isolation characteristics, and are a popular area of research in this area. However, these structures can pose difficulties for signal integrity. The proposed method extends the previous power transmission line work to address both the power supply noise generation and isolation. Test vehicles using these proposed methods, as well as using an EBG structure were fabricated and tested with regards to power supply noise, jitter, and noise isolation. The proposed methods show significant improvements in almost all performance metrics as compared to EBG. Finally, this dissertation discusses the effect of implementing a power transmission line in a power distribution network composed of a switching regulator and a voltage regulator module. The DC conductor losses of the PTL can not only affect power efficiency of the entire system, but can also affect the proper operation of the linear regulator module when supporting large currents. Consequently, recommendations are made on the design of the PTL to ensure proper operation and efficiency.