[pt] O presente trabalho busca analisar se um choque de notícia falsa que afetou os preços das ações da construtora europeia Vinci S.A., em novembro de 2016, teve algum componente de persistência na dissipação. Para tal, são construídos três modelos contrafactuais para traçar as trajetórias alternativas de preço que as ações da Vinci teriam percorrido na ausência do choque. A premissa básica do presente estudo é que os preços das ações são compostos por fundamento e por ruído (noise), sendo um choque de notícia falsa uma espécie de fenômeno natural em finanças, que torna possível separar o ruído dos fundamentos que definem o preço. Quando a informação falsa é absorvida como verdadeira, todos os agentes se tornam propagadores de ruído, ao passo que quando o ruído é revelado, o mercado deveria voltar a operar apenas com base nos fundamentos. Os resultados aqui encontrados apontam para uma rigidez temporária na trajetória de retorno do preço das ações ao seu preço fundamental após o choque, o que contraria a hipótese da incorporação imediata da informação ao preço proposta por algumas teorias de mercados eficientes. Os modelos aqui propostos mostraram-se bem especificados e as suas conclusões se corroboraram, conferindo robustez ao resultado. / [en] The present paper seeks to analyze if a fake news shock that affected the stock prices of the European construction company Vinci S.A., in November 2016, had any component of persistence in its dissipation. The paper constructs three contractual models to trace alternative trajectories for the price that Vinci stocks would have followed in the absence of the shock.The basic premise of this paper is that asset prices are composed both by noise and fundamental, and a fake news shock is a sort of natural phenomena in finance that makes it possible to identify the noise and the fundamental that compose prices. When false information is taken as true, all agents become temporally noise traders and when the noise is revealed, the market comes back to operate based on fundamental. The models point to a temporary stickiness of noise during the return of the prices to their fundamentals after the shock, contradicting the assumption of immediate incorporation of information to the price proposed by some Efficient Market Theories. The models have demonstrated to be well specified and they all have pointed to the same conclusions, conferring robustness to the results.

Abstract This research on military aviation noise was conducted because the personnel working with military aircraft were concerned about noise induced hearing damage. In addition, comprehensive data on hearing impairments and occupational exposure of military pilots in the Finnish Air Force was not available. Moreover, data on the effects of overflight noise of military jets was necessary for the evaluation of noise induced hearing deteriorations of members of the public who might be exposured accidentally for the low-level jets' overflights. The averaged noise exposure levels of pilots varied during a flight from 97 dB(A) to 106 dB(A) in the cockpit and from 83 dB(A) to 100 dB(A) at the entrance of the ear canal. Radio noise was 4–10 dB higher than background noise inside the helmet. The attenuation provided by air crew helmets varied from10 to 21 dB(A) in the laboratory, and was at the same level during real flights. The attenuation measured in the laboratory and in working conditions was about 30 dB(A) for earmuffs. An active noise cancellation (ANC) device decreased averaged noise exposure (LAeq8min) 4–8 dB over the noise attenuation of the same helmets when the ANC system was off. The noise of overflights by military jets were measured and the noise levels were lower than those known to cause the permanent threshold shifts. However, noise induced hearing damages might be possible in certain conditions. In order to assess the hearing loss risk of pilots, hearing thresholds were measured before and after one flight using both conventional and extended high frequency (EHF) audiometry. Minor temporary threshold shifts (TTS) were revealed. The risk of noise-induced damage at the studied exposure levels is, in all probability, rather small. A novel NoiseScan data management system proved to be an interesting tool in assessment of the risk of developing hearing impairment on the basis of known risk factors. Due to the small number of risk factors, the hearing of pilots was shown to be at considerably less risk than that of industrial workers in Finland.

INTRODUÇÃO: O ruído é considerado, mundialmente, como um problema de saúde pública. No ambiente escolar, o ruído é um fator de grande preocupação, devido a seus impactos e prejuízos, tanto para os alunos como para os funcionários, incluindo os professores. Os danos do ruído para as crianças podem englobar efeitos auditivos, de saúde em geral e cognitivos, afetando negativamente o desenvolvimento da aprendizagem. Dificuldades de concentração e engajamento, além de prejuízos para o sono e memória também são relatados. Muitas pesquisas vêm demonstrando que o ruído em salas de aula encontra-se acima dos valores recomendados. Desta forma, estudos que busquem a promoção da saúde auditiva e a conscientização da comunidade escolar com relação ao ruído são fundamentais, uma vez que podem contribuir para a melhoria da qualidade de vida dos atores envolvidos, bem como para a constituição de um ambiente acústico mais propício para a saúde e aprendizagem. OBJETIVOS: O objetivo geral do presente estudo foi o desenvolvimento e a verificação da eficácia de um programa de promoção de saúde auditiva em uma escola particular. Os objetivos específicos foram a verificação dos níveis de pressão sonora existentes nas dependências da escola antes e após o programa de intervenção; as queixas e o grau de desconforto com relação ao ruído dos alunos e dos professores da escola, por meio da aplicação de questionários específicos, pré e pós-intervenção; e a elaboração de uma proposta coletiva de intervenção na escola, norteada pelo Modelo Ecológico de Promoção da Saúde. MÉTODO: Participaram deste estudo alunos e funcionários de uma escola particular em Santana de Parnaíba, São Paulo. Os procedimentos realizados incluíram medições dos níveis de pressão sonora pré e pós-intervenção das salas de aulas e demais espaços da escola, aplicação de questionários pré e pós-intervenção nos alunos e professores para verificação de sintomas auditivos, extra-auditivos e grau de incômodo com o ruído no ambiente escolar. Além disso, foram realizadas as intervenções propriamente ditas, que foram desenvolvidas em conjunto a equipe da escola e alunos. RESULTADOS: Ao comparar as medições pré e pós-intervenção, pode-se observar diminuição estatisticamente significante dos níveis de ruído em determinadas salas de aula e anfiteatro. Já para outros espaços coletivos, como biblioteca e cantina, os níveis de ruído permaneceram sem diferença significante. Os questionários pré e pós-intervenção mostraram uma maior consciência acerca do ruído e intervenções efetivas para diminuição deste nas salas de aula. As intervenções realizadas conseguiram abranger todos os níveis propostos pelo Modelo Ecológico de Promoção da Saúde, com exceção do nível de políticas públicas. As ações tiveram caráter educativo, pedagógico, comunitário e físico, bem como foram desenvolvidas e implementadas em conjunto com a equipe pedagógica da escola e com os alunos. A escola realizou tratamento acústico nos espaços definidos como prioritários. CONCLUSÃO: Pode-se verificar que o programa desenvolvido, juntamente com a escola, teve impactos positivos, tais como redução nos níveis de ruído, mudanças no ambiente (tratamento acústico), bem como na cultura escolar, em relação à diminuição do ruído / INTRODUCTION: Noise is described worldwide as a public health problem. In the school environment, noise is a major concern due to the impacts and impairment it may cause in students and staff, including teachers. In the range of damage that noise may cause in children, we may enlist auditory problems, general health and also cognitive effects, which may affect their learning development. In some cases, difficulties with memory, concentration and also sleep are reported. Several studies have shown that noise in classroom is, commonly, above the recommended values. Thus, researches that aim to promote hearing health and awareness of the school community regarding noise are fundamental, since they can contribute to the improvement of life quality for education professionals, as well as for providing better acoustic environment for health and learning. PURPOSE: The overall aim of the present study was to develop and verify the efficacy of a hearing health promotion program in a private school. The specific objectives were to verify the sound pressure levels in the school before and after the intervention program; the complaints and the degree of discomfort regarding the noise of students and teachers from the school, through specific questionnaires, applied before and after intervention; and the elaboration of a collective intervention proposal in the school, guided by the Ecological Model of Health Promotion. METHODS: Participated in this study, students and employees from a private school of Santana de Parnaíba, São Paulo. The procedures performed included measurements of sound pressure pre and post intervention in the classrooms and in several environment of the school; we applied pre and post intervention questionnaires in students and teachers to verify auditory and extra-auditory symptoms and the degree of annoyance concerning noise in the school environment. Besides, we conducted intervention acts which were defined jointly with the school staff and students. RESULTS: Comparing pre and post-intervention measurements, a statistically significant reduction of noise levels was observed in some classrooms and in the amphitheater. On the other hand, for other collective places, such as library and canteen, noise levels remained without significant difference. The pre and post intervention questionnaires showed a greater awareness about noise and effective interventions to reduce it in classrooms. The interventions that we performed were effective to cover all levels proposed by the Ecological Model of Health Promotion, apart from the level of public policies. The actions were educational, pedagogical, community and physical, and they were developed and implemented in partnership with the pedagogical team and students. The school performed acoustic treatment in the spaces defined as priority. CONCLUSION: We verified that the developed program which was conducted along with the school, achieved positive impacts, such as noise levels reduction, changes in the environment (acoustic treatment), as well as in the habits of the school staff regarding noise reduction

This thesis contains glossary topic of spectroscopic measurement methods in broad bands of frequency. There is designed experimental measurement method for simple samples and biological samples measurements for noise spectroscopy in frequency range of 0,1 – 6 GHz, using broadband noise generator. There is realized the workplace and the measurement method is verified by measuring on selected samples. Measurements a displayed and analyzed.

This thesis deals with issue of traffic noise, its measurement and data evaluation. Theoretic part of my work concretes basic information about acoustics and also describes and analyzes traffic noise sources of tire/pavement. Next part deals with quite pavement and with measurement methods of traffic noise. Practical part of my thesis contains description, results and evaluation of realized measurement with methods CPX and SPB.

Despite the preventability of noise-induced hearing loss (NIHL) a high prevalence is still reported in South African mines. The study aimed to describe the hearing of gold miners pertaining to the prevalence and degree of NIHL and effectiveness of current RSA impairment criteria to identify NIHL. The audiological data, collected between 2001 and 2008, of 57 714 mine workers were investigated in this retrospective cohort study. Data was accessed through the mine’s electronic database and exported to Microsoft Excel 2007 worksheets. Participants were categorised in terms of noise exposure (level and working years), age, race and gender. Noise exposure levels were described in terms of a specific occupation and categorized into four groups based on dosimeter data received from the mine’s noise hygienist, namely: 1) Below surface (underground) noise exposure, ≥85 dB A, classified according to the South African regulations on the daily permissible dose of noise exposure8, named Noise Group 1; 2) Surface noise exposure, ≥85 dB A, named Noise Group 2; 3) No known occupational noise exposure, named control group; and 4) Uncertain levels of noise exposure, e.g. students and trainees, named Noise Group 4. The control group was matched with participants of noise group 1 and 2 based on gender, race and age at the most recent audiogram test. Descriptive and inferential statistics were employed. Measures of central tendency and variability were used with analysis of covariance (ANCOVA) and pairwise comparisons according to Fisher’s Least Squares Differences Approach (F test). Results indicated that noise exposed groups had significantly higher prevalence of high and low frequency hearing loss than the control group. High-frequency hearing loss was also present in the control group. The greatest differences in prevalence of hearing loss were observed at 3, 4 kHz and age group 36 to 45 years. Thresholds at 8 kHz were worse than expected and decline slowed down with age. High-frequency thresholds showed a non-linear growth pattern with age with a greater decline at 2 kHz with age in the noise-exposed population compared to the control group. Hearing deteriorated more across age groups with more noise-exposed years, and this deterioration was most visible after 10 to 15 working years and at 3 kHz. Females had better hearing than males across the frequency spectrum. Black males had significantly better high-frequency hearing than white males but significantly worse low-frequency hearing than white male counterparts. PLH values showed poor correlation (through statistical analyses) with other well-accepted hearing impairment criteria. To date this was the largest study conducted on the hearing of gold miners and the sample included a very large number of black males exposed to occupational noise (N=17 933). Values supplied in distribution table format are therefore unique and contribute greatly to the knowledge base. / Thesis (PhD)--University of Pretoria, 2012. / Speech-Language Pathology and Audiology / unrestricted

Although the majority of wireless receiver subsystems have moved to digital signal processing over the last decade, the low noise amplifier (LNA) remains a crucial analogue subsystem in any design being the dominant subsystem in determining the noise figure (NF) and dynamic range of the receiver as a whole. In this research a novel LNA configuration, namely the LC-ladder and capacitive shunt-shunt feedback topology, was proposed for use in the implementation of very wideband LNAs. This was done after a thorough theoretical investigation of LNA configurations available in the body of knowledge from which it became apparent that for the most part narrowband LNA configurations are applied to wideband applications with suboptimal results, and also that the wideband configurations that exist have certain shortcomings. A mathematical model was derived to describe the new configuration and consists of equations for the input impedance, input return loss, gain and NF, as well as an approximation of the worst case IIP3. Compact design equations were also derived from this model and a design strategy was given which allows for electronic design automation of a LNA using this configuration. A process for simultaneously optimizing the circuit for minimum NF and maximum gain was deduced from this model and different means of improving the linearity of the LNA were given. This proposed design process was used successfully throughout this research. The accuracy of the mathematical model has been verified using simulations. Two versions of the LNA were also fabricated and the measured results compared well with these simulations. The good correlation found between the calculated, simulated and measured results prove the accuracy of the model, and some comments on how the accuracy of the model could be improved even further are provided as well. The simulated results of a LNA designed for the 1 GHz to 18 GHz band in the IBM 8HP process show a gain of 21.4 dB and a minimum NF of only 1.7 dB, increasing to 3.3 dB at the upper corner frequency while maintaining an input return loss below -10 dB. After steps were taken to improve the linearity, the IIP3 of the LNA is -14.5 dBm with only a small degradation in NF now 2.15 dB at the minimum. The power consumption of the respective LNAs are 12.75 mW and 23.25 mW and each LNA occupies a chip area of only 0.43 mm2. Measured results of the LNA fabricated in the IBM 7WL process had a gain of 10 dB compared to an expected simulated gain of 20 dB, however significant path loss was introduced by the IC package and PCB parasitics. The S11 tracked the simulated response very well and remained below -10 dB over the feasible frequency range. Reliable noise figure measurements could not be obtained. The measured P1dB compression point is -22 dBm. A 60 GHz LNA was also designed using this topology in a SiGe process with ƒT of 200 GHz. A simulated NF of 5.2 dB was achieved for a gain of 14.2 dB and an input return loss below -15 dB using three amplifier stages. The IIP3 of the LNA is -8.4 dBm and the power consumption 25.5 mW. Although these are acceptable results in the mm-wave range it was however found that the wideband nature of this configuration is redundant in the unlicensed 60 GHz band and results are often inconsistent with the design theory due to second order effects. The wideband results however prove that the LC-ladder and capacitive shunt-shunt feedback topology is a viable means for especially implementing LNAs that require a very wide operating frequency range and also very low NF over that range. / Thesis (PhD(Eng))--University of Pretoria, 2011. / Electrical, Electronic and Computer Engineering / unrestricted

Despite our understanding of the impact of noise-induced damage to the auditory system, much less is known about the impact of noise exposure on the vestibular system. In this article, we review the anatomical, physiological, and functional evidence for noise-induced damage to peripheral and central vestibular structures. Morphological studies in several animal models have demonstrated cellular damage throughout the peripheral vestibular system and particularly in the otolith organs; however, there is a paucity of data on the effect of noise exposure on human vestibular end organs. Physiological studies have corroborated morphological studies by demonstrating disruption across vestibular pathways with otolith-mediated pathways impacted more than semicircular canal-mediated pathways. Similar to the temporary threshold shifts observed in the auditory system, physiological studies in animals have suggested a capacity for recovery following noise-induced vestibular damage. Human studies have demonstrated that diminished sacculo-collic responses are related to the severity of noise-induced hearing loss, and dose-dependent vestibular deficits following noise exposure have been corroborated in animal models. Further work is needed to better understand the physiological and functional consequences of noise-induced vestibular impairment in animals and humans.

Problem background: This thesis in building technology at Mälardalen University examines the noise level of the constructions on Öster Mälarstrand. The area Öster Mälarstrand is in the eastern part of Västerås next to the water area Mälaren. This district began to build in the end of the 20th century, and the area went from an industrial field to become as described, one of the best places in Västerås to live at. The district is now an area with a large extent of residentials and other necessities such as banking, gym, cafes, restaurants, shops and a large marina. Öster Mälarstrand is still under constant construction of new buildings. The purpose of the survey is to investigate the noise level on Öster Mälarstrand, and if the construction sites are customised to the guidelines that exist regarding noise and noise levels outside in a residential area. The work is summarized and ends by giving examples of measures to reduce noise and noise levels in the area. The method is based on own noise measurements, calculations and interviews. The noise measurements carried out at three specific locations on Öster Mälarstrand during four working days when constructions were underway. Interviews have also been conducted with 50 people who live in the area. The calculations of the noise measurments showed several varying values, but one thing that is clear is that the noise calculations that was executed, exceeds the guideline values set for noise-levels in Öster Mälarstrand. The interviews that were conducted presents that a majority of the interviewees thought that the noise level of the constructions on Öster Mälarstrand was disturbing, especially now during the pandemic of Covid-19, when several people started working from home. The conclusion in this thesis is that noise levels exceeds the guideline values ​​that exist according to the Swedish Environmental Protection Agency. The interviews in the area show that the majority of the participants experience the noise from the construction site as a disturbance.

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