Dissertations / Theses: 'Natural Noise'

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Reed, Veronica Arlene. "Natural and Experimental Noise Affects Acoustic Communication in Songbirds." DigitalCommons@CalPoly, 2021. https://digitalcommons.calpoly.edu/theses/2279.

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Background noise is ubiquitous and can impair acoustic communication and influence signaling behavior in animals. Despite evidence demonstrating myriad effects of anthropogenic noise on animal communication, precisely how natural background noise influences communication and behavior remains unclear. Yet, natural sources of background noise, such as rushing rivers or crashing ocean surf, share similar power spectra to sources of anthropogenic noise and can occur at high amplitudes, potentially masking acoustic signals. To investigate the effects of water-generated noise on songbird behavior, we experimentally broadcast landscape-level playbacks of ocean surf and river noise in coastal California, USA, and riparian habitat in Idaho, USA, respectively. In Chapter 1, we conducted a conspecific playback experiment examining how territorial defense behaviors of lazuli buntings (Passerina amoena) and spotted towhees (Pipilo maculatus) vary in response to broadcast water noise. We also incorporated cicada noise from a serendipitous Okanagana spp. emergence as a biotic source influencing lazuli bunting behavior. Both species produce songs that share substantial spectral overlap with low-frequency, water-generated noise, and lazuli bunting song shares an additional high-frequency overlap with cicada calls. Thus, there is potential for background acoustic conditions to mask conspecific signals. We found that detection and discrimination of conspecific playback occurred more slowly for both species as sound level increased. Lazuli buntings also exhibited divergent flight behaviors in response to high- and low-frequency acoustic sources, both dependent and independent of sound level. In Chapter 2, we investigated how amplitude and frequency of water-generated noise influences spectral and temporal song characteristics in six songbird species. We recorded individuals defending territories across 37 sites, with each site representing one of four acoustic environments: naturally quiet ‘controls’, naturally noisy ‘positive controls’ adjacent to the ocean or a whitewater river, ‘phantom’ playback sites with continuous broadcast of low-frequency water noise, and ‘shifted’ playback sites with continuous broadcast of high-frequency water noise. We predicted that all individuals exposed to ‘positive control’, ‘phantom’, or ‘shifted’ noise would adjust song structure, but the magnitude of signal modification would be larger in noisier locations and the type of modification would depend on the spectral profile of the acoustic environment. No two species altered songs in precisely the same way. However, song structure of all six species varied with amplitude and/or frequency of background noise. Together our results demonstrate that natural noise can impair agonistic behaviors and influence vocal structure. These findings suggest that the natural acoustic environment shapes acoustic communication, highlighting natural soundscapes as an under-appreciated axis of the environment.

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Alvarsson, Jesper J. "Stress recovery during exposure to natural sounds and environmental noise." Thesis, Stockholm University, Department of Psychology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-27894.

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Research suggests that physiological stress reactions may be reduced by visual impressions from natural environments as compared to urban or built-up environments. The present experiment tested whether similar effects might be found by auditory stimulation. Forty university students were tested in an experiment with four consecutive recovery sessions after stressful mental arithmetic tests. The independent variables were type of sound during recovery. The sound was either a natural sound environment (sounds from water and birdsong, at 50 dBA), or three types of noisy environments (traffic noises at 50 or 80 dBA or ambient background sound at 40 dBA). The main dependent variables were physiological recovery from stress, as measured by decrease in heart rate (HR) and skin conductance level (SCL) after the stressful arithmetic test. The main result was that SCL reduction was faster during nature sounds than during the various noises. For HR, no systematic effects of experimental sounds were found. The result for SCL lends some support the hypothesis that exposure to natural sounds facilitate physiological stress recovery. Sarcade

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Bolin, Karl. "Wind Turbine Noise and Natural Sounds : Masking, Propagation and Modeling." Doctoral thesis, KTH, MWL Marcus Wallenberg Laboratoriet, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10434.

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Wind turbines are an environmentally friendly and sustainable power source. Unfortunately, the noise impact can cause deteriorated living conditions for nearby residents. The audibility of wind turbine sound is influenced by ambient sound. This thesis deals with some aspects of noise from wind turbines. Ambient sounds influence the audibility of wind turbine noise. Models for assessing two commonly occurring natural ambient sounds namely vegetation sound and sound from breaking waves are presented in paper A and B. A sound propagation algorithm has been compared to long range measurementsof sound propagation in paper C. Psycho-acoustic tests evaluating the threshold and partial loudness of wind turbine noise when mixed with natural ambient sounds have been performed. These are accounted for in paper D. The main scientific contributions are the following.Paper A: A semi-empiric prediction model for vegetation sound is proposed. This model uses up-to-date simulations of wind profiles and turbulent wind fields to estimate sound from vegetation. The fluctuations due to turbulence are satisfactory estimated by the model. Predictions of vegetation sound also show good agreement to measured spectra. Paper B: A set of measurements of air-borne sound from breaking waves are reported. From these measurements a prediction method of sound from breaking waves is proposed. Third octave spectra from breaking waves are shown to depend on breaker type. Satisfactory agreement between predictions and measurements has been achieved. Paper C: Long range sound propagation over a sea surface was investigated. Measurements of sound transmission were coordinated with local meteorological measurements. A sound propagation algorithm has been compared to the measured sound transmission. Satisfactory agreement between measurements and predictions were achieved when turbulence were taken into consideration in the computations. Paper D: The paper investigates the interaction between wind turbine noise and natural ambient noise. Two loudness models overestimate the masking from two psychoacoustic tests. The wind turbine noise is completely concealed when the ambient sound level (A-weighed) is around 10 dB higher than the wind turbine noise level. Wind turbine noise and ambient noise were presented simultaneously at the same A-weighed sound level. The subjects then perceived the loudness of the wind turbine noise as 5 dB lower than if heard alone. Keywords: Wind turbine noise, masking, ambient noise, long range sound propagation QC 20100705

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Ceylan, Ciwan. "Conditional Noise-Contrastive Estimation : With Application to Natural Image Statistics." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213847.

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Unnormalised parametric models are an important class of probabilistic models which are difficult to estimate. The models are important since they occur in many different areas of application, e.g. in modelling of natural images, natural language and associative memory. However, standard maximum likelihood estimation is not applicable to unnormalised models, so alternative methods are required. Noise-contrastive estimation (NCE) has been proposed as an effective estimation method for unnormalised models. The basic idea is to transform the unsupervised estimation problem into a supervised classification problem. The parameters of the unnormalised model are learned by training the model to differentiate the given data samples from generated noise samples. However, the choice of the noise distribution has been left open to the user, and as the performance of the estimation may be sensitive to this choice, it is desirable for it to be automated. In this thesis, the ambiguity in the choice of the noise distribution is addressed by presenting the previously unpublished conditional noise-contrastive estimation (CNCE) method. Like NCE, CNCE estimates unnormalised models by classifying data and noise samples. However, the choice of noise distribution is partly automated via the use of a conditional noise distribution that is dependent on the data. In addition to introducing the core theory for CNCE, the method is empirically validated on data and models where the ground truth is known. Furthermore, CNCE is applied to natural image data to show its applicability in a realistic application. Icke-normaliserade parametriska modeller utgör en viktig klass av svåruppskattade statistiska modeller. Dessa modeller är viktiga eftersom de uppträder inom många olika tillämpningsområden, t.ex. vid modellering av bilder, tal och skrift och associativt minne. Dessa modeller är svåruppskattade eftersom den vanliga maximum likelihood-metoden inte är tillämpbar på icke-normaliserade modeller. Noise-contrastive estimation (NCE) har föreslagits som en effektiv metod för uppskattning av icke-normaliserade modeller. Grundidén är att transformera det icke-handledda uppskattningsproblemet till ett handlett klassificeringsproblem. Den icke-normaliserade modellens parametrar blir inlärda genom att träna modellen på att skilja det givna dataprovet från ett genererat brusprov. Dock har valet av brusdistribution lämnats öppet för användaren. Eftersom uppskattningens prestanda är känslig gentemot det här valet är det önskvärt att få det automatiserat. I det här examensarbetet behandlas valet av brusdistribution genom att presentera den tidigare opublicerade metoden conditional noise-contrastive estimation (CNCE). Liksom NCE uppskattar CNCE icke-normaliserade modeller via klassificering av data- och brusprov. I det här fallet är emellertid brusdistributionen delvis automatiserad genom att använda en betingad brusdistribution som är beroende på dataprovet. Förutom att introducera kärnteorin för CNCE valideras även metoden med hjälp av data och modeller vars genererande parametrar är kända. Vidare appliceras CNCE på bilddata för att demonstrera dess tillämpbarhet.

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Yang, Hong-Seok. "Outdoor noise control by natural/sustainable materials in urban areas." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4484/.

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This study explores the effects of natural and sustainable materials including vegetation, green roof systems and green walls on outdoor noise control in urban areas. The concept of this study starts with a hypothesis that well-planned use of the natural materials on building and urban surfaces can achieve useful reductions in noise levels and reverberation in urban spaces. Firstly, this study examines random-incidence absorption and scattering coefficients of vegetation through a series of measurements in a reverberation chamber in order to characterise the effects of various designable factors such as soil depths, soil water content and vegetation densities. This data is used later in acoustic computer simulations. To quantify the scattering effect of trees and to allow including it in numerical predictions, a series of measurements are carried out for individual trees in an open field. Green roof systems are placed on a low profiled structure to examine sound transmission through the vegetated low barrier. To suggest noise abatement schemes in relatively small urban spaces, the acoustic effects of landscape designs using vegetation in a courtyard are studied through a case study. As a preliminary study on the noise reduction effect of vegetation in relatively large urban spaces, field measurements are carried out at outdoor spaces in high-rise apartment complexes. Based on the measurement results, the noise reduction effect of vegetation in apartment complexes is also predicted. The overall results for each research topic can be summarised as follows: It is shown that low-growing vegetation can be an effective measure for absorbing/scattering sound energy, especially at high frequencies. Results of field measurements show that tree reverberation exerts an influence only on frequencies above 1 kHz. At 4 kHz, RT (reverberation time) can be as long as 0.28 sec. Measurements made near the same deciduous tree with and without leaves indicate that leaves increase reverberation at 4 kHz by 0.08 sec. The results on sound transmission over the low barrier with green roof systems suggest that SPL attenuation increases with the increasing green roof areas. The extra SPL (sound pressure level) attenuation caused by green roof systems could be up to 9.5 dB at certain frequencies. With well-planned application of landscape designs in a courtyard, speech levels and RT at 500 Hz are decreased by 9.3 dBA and 81 %, respectively. In outdoor spaces of apartment complexes, RT is generally rather long, over 4 sec at 500 Hz, influenced by many factors such as openness, source-receiver distance and building height. In terms of SPL distribution, the measured SPL is up to 8 dB higher compared to the semi-free field situation. It is also found that vegetation at the apartment complex can be effective in reducing RT by 0.95 sec (46 % decrease).

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Dong, Li. "Noise level estimation from single image based on natural image statistics." Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3952094.

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Saxen, Shelley Walker. "Park visitors and the natural soundscape : winter experience dimensions in yellowstone." [Missoula, Mont.] : The University of Montana, 2008. http://etd.lib.umt.edu/theses/available/etd-12112008-123204/unrestricted/umi-umt-1108.pdf.

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Thesis (Ph.D.) --University of Montana, 2008. Title from author supplied metadata. Description based on contents viewed on May 15, 2009. ETD number: etd-12112008-123204. Author supplied keywords: natural sounds ; recreation ; visitor experiences ; national park policy ; soundscape policy ; soundscape management ; winter visitor experiences ; wildland recreation. Includes bibliographical references.

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Lögdberg, Frida. "Population dynamics in variable environments – impacts of noise colour and synchrony." Doctoral thesis, Linköpings universitet, Teoretisk Biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72951.

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Environmental variation is an essential part of population dynamics, and two characteristics of such variation—variance and the temporal autocorrelation termed ‘noise colour’—are essential for determining the persistence of a population. In addition, the spatial correlation of local environmental variation between habitat patches (i.e., synchrony) is equally important in subdivided populations connected via dispersal. The research underlying this thesis explored the effects of noise colour and synchrony on population dynamics. The dynamics were studied primarily in single-species models with fast or slow population responses to environmental changes, and several-species systems (i.e., food webs) with different stability properties were also considered. Populations were spatially subdivided with local dynamics in discrete patches, and patch positions were modelled either implicitly or explicitly, with different landscape configurations in the latter case. It has previously been shown that the effect of increased environmental redness on extinction risk in nonspatial models depends on population responsiveness, seen as increased and decreased risks for fast and slow responding populations, respectively. Here, increased redness of noise decreased the extinction risk for fast-responding populations (in accordance with non-spatial studies) in a simple implicit landscape model (Papers I and II). Slow-responding populations in some cases showed a raised extinction risk for intermediate noise colour values (Paper I), which does not agree with earlier results. However, increasing the spatial complexity evened out the differences that were caused by responsiveness (Papers III and IV). Thus, in general, the explicit landscape models displayed a decrease in extinction risk with increasing environmental redness regardless of whether the populations were fast or slow in responding to environmental variation. Still, fast and slow responsiveness of populations differed in relation to the following: overall levels of extinction risk (Papers I, III, and IV), synchrony of population variations (Paper II), colour of population variations (Paper II), and response to landscape structure (Papers III and IV). For fast-responding populations, the degree of synchrony of population variations was similar to the synchrony of environmental noise (Paper II). Local populations of a model organism that responded slowly to environmental variation were more synchronized than the environmental variation itself, and the largest shift between the environment and the populations was seen for intermediate red noise colours (Paper II). This indicated that dispersal-induced population synchrony could be enhanced by reddened noise. Landscape configuration proved to be important for the general levels of extinction risk. This effect was most pronounced for fast-responding populations (Papers III and IV) and became even more distinct when distance-dependent synchrony was added between the environmental variations (Paper IV). Adding explicit landscapes led to an decrease in the differences between fast- and slow-responding populations, when considering the influence of noise colour on extinction risk. Also, landscape configuration affected the importance of degree of synchrony through its impact on distances between patches, which resulted in configurations where extinction risk depended solely on noise colour. The effects on stability exerted by populations embedded in food webs were investigated in an implicit landscape model (Paper V). Three types of food webs with different properties of inherent stability all showed a decrease in stability at increased environmental variance and increased redness of environmental variation. In conclusion, the single-species models showed that the survival conditions of populations that were near extinction were improved by all of the following: decreased synchrony, reddening of noise, and aggregation of patches. The results of the web simulations indicate that we need better understanding of how findings obtained using single-species models can be used to reveal the effects of noise colour on species communities. From a management perspective, altering landscape structure may compensate for increased extinction risks caused by changed noise colour of environmental variation, which is a predicted outcome of climate change.

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Serban, Adriana. "Ultra-Wideband Low-Noise Amplifier andSix-Port Transceiver for High Speed DataTransmission." Doctoral thesis, Linköpings universitet, Fysik och elektroteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-52954.

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Today’s data rates in wired networks can reach 100 Gbit/s using optical fiber while data rates in wireless networks are much lower - tens of Mbit/s for 3G mobile communication and 480 Mbit/s for ultra-wideband (UWB) short range wireless communications. This difference in data rates can mainly be explained by the limited allowed frequency spectrum, the nature of the radio signal and the high requirements imposed on all hardware designed for high speed and wideband wireless communications. However, the demand on wireless commercial applications at competitive costs is growing. The first step in regulations allowing higher data rates for wireless communications was taken in 2002, when the Federal Communication Commission (FCC) in USA released unlicensed the 3.1-10.6 GHz frequency band restricting only the power level (maximum mean equivalent isotropic radiated power density of a UWB transmitter is -41.3 dBm/MHz) in the band 3.1-10.6 GHz. But Europe, Japan and recently China have put additional restrictions on the 3.1-4.8 GHz band. The restrictions address the problems that have raised from the coexistence and colocation of the UWB systems with other narrowband wireless systems. Thus, the 6-9 GHz band combined with an increased modulation order scheme is of large interest. Operating at higher frequency and wider bandwidth than today’s communication technologies, with the general task of maximizing the wireless data rate while keeping the power consumption low, requires new communication system solutions and new circuit design approaches. These new solutions also require understanding of many multi-disciplinary areas which until the recent past were not directly related: from classic analog circuit design to microwave design, from modulation techniques to radio system architecture. In this thesis, new design techniques for wide bandwidth circuits above 3 GHz are presented. After focusing on ultra-wideband low-noise amplifier (UWB LNA) design for low-power and low-cost applications, the practical implementation and measurement of a 3.1-4.8 GHz UWB LNA is addressed. Passive distributed components of microstrip transmission lines are intensively used and their contribution to the UWB LNA performance is studied. In order to verify the design methodology while extending it to the UWB radio front-end, the UWB LNA is integrated on the same substrate with a pre-selecting filter with the frequency multiplexing function. In this way, the concept of frequencytriplexed UWB front-end is demonstrated for the Mode 1 multi-band UWB bandwidth 3.1-4.8 GHz. Using the proposed receiver front-end topology, better receiver sensitivity and selective operation can be achieved. The later part of the thesis investigates ultra-wideband 6-9 GHz receiver and transmitter front-end topologies for Gbit/s data rates and low power consumption. To capture the advantages offered by distributed passive components, both the transmitter and receiver use the six-port correlator as the core of a passive mixer. Modelling and design of the 6-9 GHz UWB front-end transceiver include different receiver topologies and different modulation schemes. Finally, the 7.5 GHz UWB transceiver front-end is implemented and evaluated. Measurement results confirm the large potential of the six-port UWB front-end to achieve multiple Gbit/s data rates. This may open for future solutions to meet the continuous challenge of modern communication systems: higher data rates at low power consumption and low cost.

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Kight, Caitlin Rebecca. "Acoustics of anthropogenic habitats: The impact of noise pollution on eastern bluebirds." W&M ScholarWorks, 2010. https://scholarworks.wm.edu/etd/1539616712.

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An increasing number of habitats are affected by anthropogenic noise pollution, which is often louder, has a different frequency emphasis, and may occur over a different temporal scale, than natural noise. An increasing number of studies indicate that acoustically-communicating animals in such areas can modify their vocalizations in order to make themselves heard over the noise, but many questions still remain, including: How taxonomically widespread is vocal flexibility in response to anthropogenic noise, and do all vocally flexible species employ the same mechanisms to escape acoustic masking? Are there fitness repercussions for living, communicating, and breeding in noisy habitats? and, can particular habitat features be used to predict environmental noise levels and sound propagation characteristics? Here, I present data collected from the breeding territories of eastern bluebirds (Sialia sialis ) to address each of these questions. My results add another species to the list of those who are able to avoid acoustic masking by modifying temporal and spectral traits of vocalizations. I also show that anthropogenic noise is associated with changes in several eastern bluebird breeding parameters. Finally, I demonstrate that both anthropogenic noise levels and sound propagation traits can be predicted by particular habitat characteristics.

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Mendel, Joshua Brock. "Essays on Macroeconomics and Finance." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:10767.

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The Local Multiplier: Theory and Evidence. I show that 1) the policy-relevant "global multiplier" can be written as the sum of a spending component and a taxation component, all scaled up by spillover effects, 2) the "local multiplier" is exactly the spending com- ponent, and 3) if trade is anonymous, the local effects of a shock to federal government purchases in a county will be identical to the effects of a shock to consumer demand for the exports of that locality. I estimate a bound for the local multiplier and consider spillover effects to contiguous counties. I find that a shock of $48,000 creates at least one job-year locally. Analysis at a monthly frequency suggests that these jobs are more persistent than previously estimated. Evidence of higher multipliers in recessions is mixed. Economics

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Pedersen, Eja. "Human response to wind turbine noise : perception, annoyance and moderating factors." Doctoral thesis, Göteborg : Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, The Sahlgrenska Academy, Göteborg University, 2007. http://hdl.handle.net/2077/4431.

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Niklasson, Lucas. "Low Intensity Natural Sounds and Pink Noise’s Effect on Attention." Thesis, Umeå universitet, Institutionen för psykologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-169713.

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Bakgrundsljud och hur det influerar människors uppmärksamhet är undersökt i ett flertal olika former. Vanligtvis genom att använda musik och tystnad som variabler för att jämföra effekten på en primär kognitiv uppgift. Eftersom all musik skapas med intentionen att lyssnas på, dvs. att dra uppmärksamheten till sig, söker denna studie att undersöka huruvida bakgrundsljud ligger till grund för olika reaktionstid beroende på om ljudet är artificiellt eller naturligt (ljud från naturen som en strömmande bäck jämfört med rosa brus). Genom att använda ett visuellt oddball-paradigm på ett reaktionstids-test med de två bakomliggande ljuden på en population (N = 30) där snittåldern var 29 (M = 29.70, SD = 7,82). T-testet bekräftade hypotesen. Därför fastslår denna tes att rosa brus ger längre tid på reaktionstids-test än naturliga ljud när de presenteras som bakgrundsljud. Background noise and how it influences attention in humans is researched in various ways and forms. Usually it has been done by using music and silence to compare the effects on a primary cognitive task. Since music is an artificial sound created with the intention to draw attention to it, the present study sought to determine if background noise cause differences in reaction time whether it was artificial noise or natural noise (such as the sound of a stream of water compared to pink noise). The two background noises were compared through a visual oddball paradigm measuring reaction time on a sample (N = 30) whose mean age was 29 years (M = 29.70, SD = 7,82). The paired t-test confirmed the hypothesis. Therefore, this study concludes that pink noise creates longer reactions compared to natural sounds when presented as background noise.

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Sarma, Subramonia P. "Relationship between suspicious coincidence in natural images and contour-salience in oriented filter responses." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/472.

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Salient contour detection is an important lowlevel visual process in the human visual system, and has significance towards understanding higher visual and cognitive processes. Salience detection can be investigated by examining the visual cortical response to visual input. Visual response activity in the early stages of visual processing can be approximated by a sequence of convolutions of the input scene with the difference-of-Gaussian (DoG) and the oriented Gabor filters. The filtered responses are unusually high for prominent edge locations in the image, and are uniformly similar across different natural image inputs. Furthermore, such a response follows a power law distribution. The aim of this thesis is to examine how these response properties could be utilized to the problem of salience detection. First, I identify a method to find the best threshold on the response activity (orientation energy) toward the detection of salient contours: compare the response distribution to a Gaussian distribution of equal variance. Second, I justify this comparison by providing an explanation under the framework of Suspicious Coincidence proposed by Barlow [1]. A connection is provided between perceived salience of contours and the neuronal goal of detecting suspiciousness, where salient contours are seen as affording suspicious coincidences by the visual system. Finally, the neural plausibility of such a salience detection mechanism is investigated, and the representational effciency is shown which could potentially explain why the human visual system can effortlessly detect salience.

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Stiewe, Fabian [Verfasser], Oskar [Akademischer Betreuer] Hallatschek, Christoph F. [Akademischer Betreuer] Schmidt, and Eleni [Akademischer Betreuer] Katifori. "The Level of Noise Controls the Efficiency of Natural Selection in Growing Biofilms / Fabian Stiewe. Gutachter: Christoph F. Schmidt ; Eleni Katifori. Betreuer: Oskar Hallatschek." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1066427488/34.

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Norberg, Hanna. "Utredning av Umeå universitets gemensamma föreläsningssalars ljudmiljöer och rumsakustik : Med fokus på taluppfattbarhet, efterklangstid samt installationsbuller." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-144182.

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The purpose of this report was to investigate the sound environments in lecture halls at Umeå University and to assess to whether the sound environments in these lecture halls are satisfactory and whether have good speech intelligibility or not. Based on a web survey, a number of lecture halls were selected for this investigation, namely Hörsal A, Hörsal C, N280, KB.F3.01, Ma121, KB.E3.01, N340 and N335. Assessing room acoustics includes many relevant parameters, therefore a delimitation has been made. Only installation noise, reverberation time and speech intelligibility have been investigated. The methods followed established Swedish standards i.e SS-EN ISO 16032:2004 for installation noise,” integrated impulse response method” SS-EN ISO 3382:2:2008/AC:2009 for reverberation time and direct FULL STI (speech transmission index) IEC 60268-16:2011 for speech intelligibility. An ocular inspection was carried out of all the selected lecture halls. The result from the STI test showed that all the lecture halls except for Hörsal A have a good speech intelligibility, if the audience has normal hearing and they are listening to a lecture in their native language. In Hörsal A there are three measuring positions that fails to achieve the threshold for good speech intelligibility. The conclusion for all of the measurements that has been made are that Ma121 and KB.E3.01 has a satisfactory sound environment and that Hörsal A, Hörsal C, N280, KB.F3.01, N340 and N335 need actions to improve their sound environment so they can fulfil the benchmarks in Swedish public health authority regulations in FoHMFS 2014:13 and/or SS 25268:2007.

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Neubauer, Paola Mezzomo. "ESTUDO COMPARATIVO ENTRE DIVERSAS COMPOSIÇÕES COM PISOS FLUTUANTES DE MADEIRA NATURAL ASSOALHO E TACOS QUANTO AO ISOLAMENTO DO RUÍDO DE IMPACTO." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/7722.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The proposal of this project is analyze and compare different behaviors of natural floating wood floors, submitted an impact noise with several compositions, used in construction industry. The tests were done on the Thermo-acoustic Laboratory of UFSM, in according with the methods specified in the regulations ISO 140/ VI and ISO 717-2. The tests were done, using layers of wood, in different compositions and resilient materials. The results were analyzed, confronting the material with same characteristics but with different composition. The resilient materials used in the tests were: glass wool, polyethylene and polystyrene. The analysis of the results was done grouping the similar materials with different compositions. Esta pesquisa faz uma análise e comparação de diferentes sistemas de pisos flutuantes de madeira natural submetidos a ruído de impacto, em diferentes composições utilizadas na indústria da construção civil. Os ensaios foram realizados nas câmaras para medir ruído de impacto do Laboratório de Termoacústica da UFSM, conforme metodologias especificadas nas Normas Internacionais ISO 140/ VI e ISO 717-2. Foram ensaiadas amostras de revestimento do tipo tábua corrida e taco, ambos de madeira natural, em diferentes composições quanto ao revestimento e o material resiliente. Os materiais resilientes utilizados nas composições foram lã de vidro, polietileno expandido e poliestireno expandido (isopor). A análise dos resultados obtidos foi feita agrupando-se materiais semelhantes nas diferentes composições.

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Grabasck, Jaqueline Ramos. "Aspectos e impactos ambientais decorrentes da extração de agregado natural e produção de agregado reciclado: estudo de caso no RS." Universidade do Vale do Rio dos Sinos, 2016. http://www.repositorio.jesuita.org.br/handle/UNISINOS/5398.

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Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-06-15T16:12:16Z No. of bitstreams: 1 Jaqueline Ramos Grabasck_.pdf: 5267584 bytes, checksum: 3825ecf690630d4c9e3ed363b7a4647d (MD5) Made available in DSpace on 2016-06-15T16:12:16Z (GMT). No. of bitstreams: 1 Jaqueline Ramos Grabasck_.pdf: 5267584 bytes, checksum: 3825ecf690630d4c9e3ed363b7a4647d (MD5) Previous issue date: 2016-03-31 CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior FAPERGS - Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul Os altos índices de consumo de recursos naturais e a geração de resíduos contribuem para os altos impactos ambientais da indústria da construção civil. A utilização de agregado reciclado a partir do beneficiamento dos resíduos de construção e demolição (RCD), embora seja fortemente incentivada pela legislação brasileira, ainda é incipiente. Porém, tanto o processo de extração de areia quanto o de beneficiamento de resíduos geram impactos ambientais e devem seguir uma série de legislações e limites de diferentes aspectos.Neste contexto, o objetivo deste trabalho consiste em analisar aspectos e impactos ambientais decorrentes da extração de areia natural e do beneficiamento do agregado reciclado de resíduos de construção e demolição. A primeira etapa da pesquisa consistiu em localizar as jazidas de extração de areia e as usinas de reciclagem de resíduos de construção e demolição, em âmbito nacional, por meio de pesquisas bibliográficas, sites do Governo e de organizações. Na segunda etapa da pesquisa, para realizar as avaliações de significância de aspectos e impactos ambientais foram visitadosdois empreendimentos, uma usina de reciclagem de RCD na Mesorregião Metropolitana de Porto Alegre e uma jazida de extração de areia na Mesorregião Centro Oriental Rio-Grandense. Ambos os processos apresentaram impactos com classificação crítica, ou seja, que acarretam em danos irreversíveis ao meio ambiente. Para averiguar a classe de risco na qual a qualidade do ar se enquadra, foram realizadas medições de concentrações de material particulado e determinada a taxa de sulfatação, sendo que apenas a emissão de material particulado apresentou valores acima dos estabelecidos pelas legislações vigentes. Por meio da quantificação do nível de pressão sonora, ficou evidente a necessidade de utilização de equipamentos de proteção individual (EPI’s) durante a operação da draga de extração e do britador. Os cálculos de emissões de CO2 indicaram que grandes deslocamentos fazem com que a utilização de areia natural extraída próxima ao consumo seja menos impactante do que o agregado reciclado, considerando a falta de usinas em todas as regiões. Entretanto, em locais que não há jazidas de areia natural, a instalação de usinas de reciclagem faz-se oportuna. The high rates of natural resource consumption and waste generation contribute to the high environmental impacts of the construction industry. The use of recycled aggregate from Construction and Demolition Waste (CDW) processing, although it is strongly encouraged by Brazilian law it, is still incipient. However, either the sand mining process as waste processing generate environmental impacts and must follow a series of laws and limits of different aspects. In this context, the objective of this study wasto analyze the environmental aspects and impacts of natural sand extraction compared to the processing of recycled household waste from construction and demolition. The first stage of the research was to find the sand extraction mines and plants of recycling of waste from construction and demolition, nationwide, through literature searches, government sites and civil organizations. In the second stage of the research, to undertake the assessments of significance of environmental aspects and impacts two entreprises were visited, one construction and demolition waste (CDW) recycling plant in Metropolitan Porto Alegre and sand extraction quarry in Mesoregion East Center Rio Grande. Both processes presented critical impact rating, ie, which lead to irreversible damage to the environment. To determine the risk class in which the air quality falls, measurements were made of particulate matter concentrations and determined the sulfation rate. Only the emission of particulate matter presented values above established by current legislation. By quantifying the sound pressure level, it was evident the need for use of equipments for individual safety (EIF) during operation of the dredge mining and crusher. The calculation of CO2 emissions indicated that because of large displacements cause the next extracted using natural sand consumption is less harmful than the recycled aggregate, considering the lack of plants in all regions. However, in places where there is no natural sand deposits, the installation of recycling plants becomes urgent.

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Bottelin, Pierre. "Caractérisation des phases pré-et post-rupture d'éboulements rocheux de taille intermédiaire : apport des enregistrements sismiques." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU015/document.

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Les éboulements rocheux de volume intermédiaire (103-105 m3) posent un problème sérieux dans les régions montagneuses en raison de leur fréquence d'occurrence relativement élevée et de leur fort pouvoir destructeur. En conséquence, il est difficile de mener des travaux de protection pour réduire l'aléa, ce qui souligne le besoin de techniques de suivi et d'alerte précoce avant la rupture. Après l'éboulement, peu d'informations quantitatives sont disponibles sur la phase de propagation en raison de la soudaineté du phénomène et de sa localisation dans des pentes raides et difficiles d'accès. Dans ce travail de thèse, une approche expérimentale est proposée pour extraire des informations à partir d'enregistrements de signaux sismiques durant les phases pré- et post-rupture d'éboulements.La première partie de ce travail vise à tester la pertinence des vibrations ambiantes pour le suivi temporel de la réponse dynamique de compartiments rocheux lors de la phase pré-rupture. Cette technique (couramment employée en génie civil pour le suivi de l'intégrité des structures) permet d'extraire les fréquences de résonance d'une structure, dont la décroissance peut traduire l'endommagement. Une étude antérieure menée sur une colonne calcaire instable a montré une décroissance d'environ 30% de la fréquence fondamentale de résonance (f1) environ deux semaines avant la rupture, interprétée comme une diminution de la rigidité du contact avec le massif stable adjacent Mid-size rockfalls (103-105 m3) represent a substantial hazard in mountainous areas, because of relative high rate of occurrence and destructive power. Consequently, few protection means can be applied, emphasizing the need for monitoring techniques and early warning prior to the collapse. After the rupture, quantitative information on the rockfall propagation phase is scarce, owing to their suddenness and location in steep and rugged slopes. In this thesis work, an experimental approach is proposed to derive valuable information from seismic records during rockfall pre-rupture and post-rupture phases. The first part of this work aims at testing the applicability of the ambient vibration technique to monitor unstable rock compartments dynamic response in the pre-rupture phase. This technique (commonly employed in civil engineering for structural health monitoring) reveals the resonant frequencies of a structure, a decrease in frequency revealing potential damage. A previous case study of an unstable limestone compartment brought to light a #30% decrease in fundamental resonant frequency (f1) two weeks before the collapse. Following this innovative work, we selected and instrumented four prone-to-fall medium-size rock compartments located in the Occidental Alps, showing various geological contexts (limestones, argillite and shale-sandstone series), deformation patterns and failure mechnisms. Ambient vibrations recorded on-site revealed caracteristic seismic noise features. Spectral peaks were observed and attributed to resonant frequencies of the rock compartments, the fundamental resonant frequency (f1) showing clear polarization parallel to the line of maximum slope gradient, and perpendicular to the main bounding fracture observed at most of the sites. Similar findings were made for an unstable rock compartment located in a volcanic caldera, characterized by rapid morphological changes and intense rockfall activity. The dynamic response of the rear fracture network was explored, showing that spectral content of seismic noise is controlled by the caldera structure in the 0.5-5 Hz range. The direction of vibration is polarized perpendicularly to the fractures, while vibration amplitudes are linked to compartment uncoupling from the rock massif. In this case, the physical origin of seismic noise amplification may be due to complex 2D or 3D resonance effects. For the four alpine sites, the fundamental frequency f1 was monitored over more than one year, showing fluctuations clearly correlated with temperature oscillations. The thermal control over f1 is highly complex, showing both positive and negative correlations, depending on site morphology and destructuration, as well as on the studied oscillations periods (daily or seasonal). No change in fundamental frequency resulting from damage was observed over this time span. One site, characterized by intense rock fracturing and a deep-open rear fracture, showed high f1 sensitivity to temperature changes. Thermo-mechanical numerical simulations revealed that both material contraction-dilation and thermal dependancy of the elastic modulus control f1 fluctuations. In addition, high amplitude seasonal f1 oscillations were explained by ice formation in the rear fracture. A criterion was developped to separate thermal-induced f1 fluctuations from damage effects, under the hypothesis that thermal sensitivity of a rock compartment increases towards failure. The second part of this work relates to the post-rupture phase of rockfalls. The seismic records generated by two mid-size rockfalls {one natural, one provoked{ that occured in the same place were analyzed, showing complex enveloppe and spectrogram features. Both events showed close magnitude, duration and spectral content. The seismic signals of the provoked event were calibrated using video shots, allowing estimation of fallen material velocity during the successive propagation phases

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Le, Breton Mathieu. "Suivi temporel d'un glissement de terrain à l'aide d'étiquettes RFID passives, couplé à l'observation de pluviométrie et de bruit sismique ambiant." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAU013.

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La surveillance d’un glissement de terrain vise à anticiper sa rupture pour réduire le risque d’accident. Elle s'opère généralement en mesurant les déplacements du sol. Ce travail propose une nouvelle technique de mesure de déplacement de glissements, flexible et à bas coût, basée sur l’utilisation d’étiquettes d’identification radiofréquence (RFID). La méthode de localisation d’étiquettes par différence de phase à 866 MHz est explorée en conditions extérieures et sur de longues durées. Cette étude a montré une détérioration de la mesure causée par les variations de température, d’humidité, de neige et de végétation. Après application de corrections, la précision de mesure a été améliorée, passant de ±20 cm à ±1 cm en conditions extérieures courantes. Cette technique fonctionne également en conditions neigeuses et en présence d’herbes hautes, mais avec une incertitude de mesure plus élevée (±8 et 4 cm respectivement). Ces erreurs de mesure sont provoquées par des effets de propagation, d’interférence multitrajets, et de per-turbations à proximité des antennes. Un système de mesure en continu a été déployé sur le glissement de terrain de Pont-Bourquin, en Suisse, pendant cinq mois. Ce dispositif a validé l’efficacité de la technique en conditions réelles. De plus, la mesure résiste bien aux intempéries et le dispositif demande peu de maintenance, en comparaison avec les techniques conven-tionnelles (extensomètre, GPS, station totale).Deux méthodes de mesure complémentaires aux déplacements ont ensuite été étudiées. La méthode de corrélation de vibrations ambiantes est prometteuse, mais n’a pas encore été utilisée en surveillance opérationnelle. Une étude bibliographique souligne plusieurs verrous à lever, tels que la correction des variations saisonnières et journalières, l’augmentation de la résolution temporelle, et le choix des paramètres de traitement adaptés au site surveillé. La méthode qui consiste à inverser une fonction de transfert entre des données de pluie et de déplacements est ensuite étudiée. Une inversion haute résolution de cette fonction est proposée. Elle permet d’identifier des comportements hydrologiques complexes (ex : infiltration à deux vitesses sur le site de Pont-Bourquin) et de mesurer leur évolution. Les avancées de cette thèse vont permettre d’améliorer la surveillance opérationnelle tout en réduisant son coût, répondant aux besoins des collectivités territoriales Landslide early-warning systems are based primarily on monitoring the displacement of the landslide. This work develops a new technique for monitoring these displacements, using radio-frequency identification (RFID) passive tags and phase-based location technique. This technique is deployed for the first time outdoors and for several months. Outdoor conditions revealed strong environmental influences due to temperature variations, moisture, snow and vegetation. These can cause a ±20 cm measurement uncertainty over a year, which is too large for landslide monitoring applications. The correction of these effects allows reaching the accuracy of ±1 cm under normal conditions, ±8 cm with snow and ±4 cm with dense high grass. The remaining effects due to snow and grass are explained by the influence of this material on the direct propagation, on the multipath interferences and on the antennas. This measurement system has been deployed on the Pont-Bourquin landslide for five months. The results validate the technique for landslide monitoring applications. The technique also shows the operational benefits of robustness to bad weather, easy maintenance and low-cost material, compared to conventional techniques (extensometer, GPS, total station).This thesis then studies two complementary monitoring methods that had recently been shown to provide precursors to landslide rupture. First, ambient seismic noise interferometry is used to detect a drop of shear-wave velocity prior to a rupture. The seismic method was studied in the literature to identify what must be developed to use this technique in an operational early-warning system. It requires getting rid of daily and seasonal environmental influences, choosing the processing parameters appropriate to the monitored landslide, and improving the temporal resolution below one day while keeping a stable enough signal. The other method consists of inverting an impulse response between rainfall and displacement rate, with a high resolution. It can shed light on complex infiltration processes (e.g. infiltration with two different delays at Pont-Bourquin) and detect their abnormal evolution across time. These developments should improve landslide operational monitoring with a low budget

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Burian, Josef. "Výpočtové modelováni komplexních vlastních frekvencí tramvajového kola při průjezdu zatáčkou." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254382.

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This Master’s thesis deals with the computational modeling of complex natural frequencies of the tram wheels during cornering. The aim of this work is to determine eigenvalues, perform analysis of the influence of different parameters on eigenvalues and perform harmonic response analysis in order to find surface velocities that can be used in future noise emission analysis.

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Koussa, Faouzi. "Evaluation de la performance acoustique des protections antibruit innovantes utilisant des moyens naturels : application aux transports terrestres." Phd thesis, Ecole Centrale de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00776758.

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Le bruit dû aux infrastructures de transports terrestres fait partie des premières préoccupations environnementales de ce début de 21e siècle. Un moyen utilisé pour réduire ce bruit est de placer des protections acoustiques le long des grands axes routiers et ferroviaires. Actuellement, les choix de ces protections antibruit se portent généralement sur des solutions traditionnelles : écran droit, merlon, écran incliné, écran avec un couronnement. Le but de ce travail est de proposer des protections acoustiques innovantes utilisant des moyens naturels et d'en étudier la performance acoustique en utilisant des approches numériques et expérimentales. L'approche numérique peut être couplée en outre à un outil d'optimisation, développé dans cette thèse, pour chercher des formes améliorées de tels dispositifs antibruit novateurs. Après une présentation des principaux phénomènes mis en jeu dans la propagation des ondes acoustiques en milieu extérieur complexe, un état de l'art des principaux écrans acoustiques dédiés aux transports terrestres a été établi, permettant de choisir trois protections antibruit innovantes pour en étudier la performance acoustique. Une analyse des principales méthodes de simulation numérique, de mesure et d'optimisation des protections antibruit a permis de choisir les méthodes adaptées à notre problématique des écrans acoustiques utilisant des moyens naturels. Les méthodes choisies ont été utilisées dans ce travail pour évaluer la performance acoustique de ces écrans innovants. Pour le premier écran choisi, dit écran en gabions, nous avons effectué des mesures in-situ et sur modèles réduits, ainsi que des simulations numériques montrant une efficacité satisfaisante. Pour le deuxième écran, utilisant des cristaux soniques, et pour le troisième écran, de type merlon acoustique de forme complexe, nous avons réalisé une étude numérique paramétrique suivie d'une étude d'optimisation. Les résultats des calculs ont montré l'intérêt de tels dispositifs antibruit pour réduire le bruit de circulation routière et ferroviaire en milieu urbain et ils ont abouti à des formes améliorées des protections acoustiques utilisant des moyens naturels.

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Wilson, Ashley A. "SENSORY STRESSORS IMPACT SPECIES RESPONSES ACROSS LOCAL AND CONTINENTAL SCALES." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2224.

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Pervasive growth in industrialization and advances in technology now exposes much of the world to anthropogenic night light and noise (ANLN), which pose a global environmental challenge in terrestrial environments. An estimated one-tenth of the planet’s land area experiences artificial light at night — and that rises to 23% if skyglow is included. Moreover, anthropogenic noise is associated with urban development and transportation networks, as the ecological impact of roads alone is estimated to affect one-fifth of the total land cover of the United States and is increasing in space and intensity. Existing research involving impacts of light or noise has primarily focused on a single sensory stressor and single species; yet, little information is known about how different sources of sensory stressors impact the relationships within tightly-knit and complex systems, such as within plant-pollinator communities. Furthermore, ANLN often co-occur, yet little is known about how co-exposure to these stressors influences wildlife, nor the extent and scale of how these stressors impact ecological processes and patterns. In Chapter 1, we had two aims: to investigate species-specific responses to artificial night light, anthropogenic noise, and the interaction between the two by using spatially-explicit models to model changes in abundance of 140 of the most prevalent overwintering bird species across North America, and to identify functional traits and contexts that explain variation in species-specific responses to ANLN stressors with phylogenetically-informed models. We found species that responded to noise exposure generally decreased in abundance, and the interaction with light resulted in negative synergistic responses that exacerbated the negative influence of noise among many species. Moreover, the interaction revealed negative emergent responses of species that only reacted when both ANLN were presented in combination. The functional trait that was the most indicative of avian response to ANLN was habitat preference. Specifically, species that occupy closed habitat were less tolerant of both sensory stressors compared to those that occupy open habitat. Species-specific responses to ANLN are context-dependent; thus, knowing the information that regulates when, where, how, and why sensory pollutants influence species will help management efforts effectively mitigate these anthropogenic stressors on the natural environment. In Chapter 2, using field-placed light manipulations at sites exposed to a gradient of skyglow, we investigated the influence of direct and indirect light on the yucca-yucca moth mutualism by quantifying chaparral yucca (Hesperoyucca whipplei) fruit set and the obligate moth (Tegeticula maculata maculata) larval density per fruit. Although many diurnal insects are thought to exhibit minimal phototaxis, we show that direct light attracted adult moths and incited higher pollination activity, resulting in an increase in fruit set. However, larval recruitment decreased with elevated light exposure and the effect was strongest for plants exposed to light levels exceeding natural moonlit conditions (> 0.5 lux). Contrarily, increases in ambient skyglow resulted in an increase in both fruit set and larva counts. Our results suggest that plant-pollinator communities may respond in complicated ways to different sources of light, such that novel selection pressures of direct and indirect light have the potential to benefit or disrupt networks within complex diurnal plant-pollinator communities, and ultimately alter the biodiversity reliant on these systems. By analyzing pervasive stressors across a continental-wide scale, we revealed considerable heterogeneity in avian responses to light and noise alone, as well as the interaction between them. Based on overall responses to the interaction between light v and noise, we suggest management efforts should focus on ameliorating excessive noise for overwintering bird species, which should decrease the impact from synergistic responses, as well as the negative impact from noise alone. There is still much to learn about responses to these stressors and smaller-scale studies should take our approach of systematically assessing interaction responses to ANLN. Moreover, our small-scale study revealed both local sources of direct light and skyglow impact the recruitment for both yucca moths and their reciprocal plant hosts. However, it is still unknown if or why other diurnal pollinators experience positive phototaxis, and whether direct lighting influences the physiology, behavior, or multiple factors relating to reproduction and fitness. Correspondingly, it is unknown if the novel selection pressures of direct and indirect light are disrupting complex diurnal plant-pollinator communities. Future research on artificial night light will need to investigate the intricate responses of diurnal pollinators to both direct and indirect light that will identify concrete mechanisms relating to physiological or behavioral susceptibility and inform predictions on how wide-spread communities will shift with this global driver of emerging change.

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Wisniewski, Christopher D. "Conserving Connecticut's Natural History| Bat Communities and Habitat Use Post-White-Nose Syndrome." Thesis, Southern Connecticut State University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10807785.

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Community ecology investigates questions related to the density, growth/decline and movements of species over time in given geographical regions. This study investigated similar questions regarding communities of endemic bat species in Connecticut. White-nose syndrome (WNS) has recently killed millions of bats in New England, yet few large-scale conservation efforts have occurred in Connecticut and few data have been published on the status of Connecticut bats post-WNS. This study aimed to: 1) survey bats persisting in WNS regions to document whether changes have occurred in species biodiversity, richness, distribution and habitat use; and 2) measure seasonality effects from summer through pre-hibernal months. Bat presence and activity were recorded using bat detectors set in grassland and forested habitats, near bodies of water and near anthropormorphic and geologic structures across Connecticut. Bioacoustics data have been analyzed by using Sonobat© software. Combined, these data show that bat activity varies significantly across habitat type (p = 0.02) and over seasons (p = 0.05). Additionally, these data provide insight regarding relationships between individual species, and clumped species groups, with habitat types and across seasons. Ultimately, these data show how bat communities have changed over time in a post-WNS environment. Combined, these data can help drive future wildlife conservation, outreach, education and management practices.

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Chavarry, Silvera Thomas Roy Eduardo, and García Emil Frank Reátegui. "Propuesta para mejorar la aplicación del sistema de gestión de seguridad y salud en el trabajo para reducir la hipoacusia profesional en los trabajadores del área de compactación de una empresa distribuidora de gas natural en Lima Metropolitana." Bachelor's thesis, Universidad Ricardo Palma, 2015. http://cybertesis.urp.edu.pe/handle/urp/1302.

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El desarrollo de la presente tesis busco comprobar los errores en la aplicación de la identificación de peligros, evaluación de riesgos y Controles (IPERC), el grado de compromiso del trabajador y la política del sistema de gestión de seguridad y salud en el trabajo, con el objetivo determinar una propuesta para mejorar la aplicación del Sistema de gestión de seguridad y salud en el trabajo para reducir la perdida de la capacidad auditiva denominada “hipoacusia profesional” en los trabajadores del área de compactación de una Empresa Distribuidora de Gas Natural en Lima Metropolitana. Durante el desarrollo se identificó en el área de compactación un porcentaje del 55% de trabajadores con hipoacusia profesional. Para identificar el peligro potencial de esta enfermedad ocupacional se realizó mediciones de la exposición al ruido en los trabajadores, determinando que la contaminación presentada durante sus actividades alcanzaron niveles de 98.90 dB superando los limites máximos permisibles de 85 dB para una jornada de 8 horas (Decreto supremo 357, 2012) convirtiéndose en el mayor riesgo del lugar de trabajo. La propuesta de mejora en el Sistema de gestión de seguridad y salud en el trabajo fue el de proponer una nueva matriz de identificación de peligros, evaluación de riesgos y controles (IPERC) estableciendo nuevos controles para reducir el riesgo por la exposición del ruido, para esto se calculo la protección auditiva adecuada para resguardar la salud del trabajador, proponiendo una doble protección auditiva; se buscó tener un personal capacitado para el puesto proponiendo un programa de certificación de trabajadores del área de compactación. Además de proponer un programa de incentivos para mejorar el compromiso del trabajador que cumpla con los estándares de seguridad y salud en el trabajo. The development of this thesis looking check for errors in the application of hazard identification, risk assessment and controls (IPERC), the degree of commitment and political worker management system safety and health at work, with the aim to determine a proposal for improving the implementation of the management system of health and safety at work to reduce the loss of hearing called "professional hearing loss" workers in the area of compaction of a Natural Gas Distribution Company in Delhi . During development it was identified in the compaction area percentage of 55% of hearing loss professional workers. To identify the potential of this occupational disease risk exposure measurements were performed on workers to noise, pollution determining that presented during their activities reached 98.90 dB levels exceeding the maximum permissible limits of 85 dB for an 8-hour day (decree Supreme 357, 2012) becoming the greatest risk in the workplace. The proposed improvement in the management system of health and safety at work was to propose a new array of hazard identification, risk assessment and controls (IPERC) establishing new controls to reduce the risk of noise exposure to this proper hearing protection was calculated to protect worker health, proposing a double hearing protection; He sought to have qualified for the position proposing a certification program area workers compaction staff. In addition to proposing an incentive program to improve employee engagement that meets the standards of safety and health at work.

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Tabassum, Binte Jafar Jeniya. "Information Extraction From User Generated Noisy Texts." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1606315356821532.

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Mediastika, Christina E. "Design solutions for naturally ventilated houses in a hot humid region with reference to particulate matter and noise reduction." Thesis, University of Strathclyde, 1999. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21430.

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Pollution in developing countries is generally much worse than in developed countries, and is caused by the widespread use of poor quality machines both industrial and in motor vehicles. Obviously, motorised vehicles are a major source of today's pollution. Motor vehicle emissions, whether gases, particulate matter or noise, can all be dangerous. Particulate matter, especially very fine particulates, is the major concern of this thesis, which considers their capacity for penetrating deep into the lungs and developing slowly to cause noticeable illnesses. Low-income people who live within the city centre are the most exposed to traffic pollution whether on the move or indoors. Low cost housing, whether self built or provided by government or private sectors, often exposes occupants to both lack of thermal comfort and pollutant intrusion from adjacent street traffic. Houses in warm-humid regions depend on large openings and through ventilation for thermal comfort. Openings allow air pollution and noise to penetrate these houses easily, thereby affecting the health, comfort and well-being of residents. Closing all openings and changing from natural ventilation to air conditioning is not however a practical solution for low cost housing. This study explores the effect of boundary fences, vegetation, and detailed opening design in reducing the penetration of airborne particulates and noise into the living spaces of typical low-cost urban houses. The experiments carried out for this study include computational simulation, manual calculation and field experiments. The research indicated that there are feasible and practical solutions to the reduction of fine particulate matter and street noise in such housing by using solid and massive barriers combined with vegetation and a specific window type. Solid and massive barriers were constructed to slow the progress of the pollutants by reduction of wind speeds on approaching obstructions. If the wind slows down enough, this effectively 'holds' the pollutant in place. In this case, the deposition surface was provided by vegetation with dense foliage. The surface of the vegetation was predicted to deposit particulate matter effectively, which would then be washed away naturally by rains. Some types of leaves were studied to find the relationship between the physical characteristics of leaf surfaces and their ability to deposit particulate matter. Before entering the living spaces, the particulate matter then encounters further obstruction by jalousie windows thus reducing its concentration. The solid and massive fence also created an acoustic shadow and noise was then further reduced by the jalousie windows. The resulting indoor noise level was found to be closer to the proposed Indonesian standards of 45 dBA.

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Xue, Boyu. "3D Printed Lattice Structure for Driveline Applications." Thesis, KTH, Materialvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299270.

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Lattice structures have received a lot of attention as cellular materials in recent years because of their outstanding properties, such as high strength-to-weight ratio, heat transfer, energy absorption, and capability of improving noise, vibration and harshness (NVH) behavior. This type of structure received a boost from additive manufacturing (AM) technology, which can fabricate geometries in practically any shape. Due to economic and environmental requirements, lightweight design is increasingly used in automobile and construction equipment applications. NVH behavior is a crucial issue for construction equipment. However, the conventional structures' NVH behavior is mainly decided by the mass, so silence often requires heavy systems, leading to more energy consumption and emission. Therefore, the environmental trends and the resulting economic competition have limited traditional (heavy) solutions to improve NVH behavior and make the lightweight design more difficult. Novel solutions are necessary to light the difficulty and challenge of combining NVH and lightweight requirements. In this research, topology optimization was implemented on a New Articulated Hauler Transmission (NAHT) component to balance lightweight and NVH behavior. The topology- optimized 3D model was filled by a non-homogenous lattice structure with optimal lattice density via size optimization. Lattice structure optimization is one type of topology optimization, and it is the term for describing these procedures. To fabricate the complicated lattice structure, additive manufacturing (or 3D printing) is required (after topology and lattice structure optimization). The new models were analyzed using the finite element method (FEM), and the results of the analysis were compared with those of the original models. After the comparison, positive results were obtained, demonstrating that topology and lattice optimization can be applied in the design of construction equipment components. According to the results, lattice structure optimization can create a reliable lightweight design with good NVH behavior. Furthermore, lattice structure's organization and layout have a significant impact on the overall performance. Gitterstrukturer har fått mycket uppmärksamhet som cellulära material under de senaste åren på grund av deras enastående egenskaper, t.ex. hög hållfasthet i förhållande till vikt, värmeöverföring, energiabsorption och förmåga att förbättra buller-, vibrations- och bullerskador (NVH-beteende). Denna typ av struktur har fått ett uppsving av tekniken för additiv tillverkning (AM), som kan tillverka geometrier i praktiskt taget vilken form som helst. På grund av ekonomiska och miljömässiga krav används lättviktsdesign i allt större utsträckning inom bilindustrin och byggnadsutrustning. NVH-egenskaperna är en viktig fråga för anläggningsutrustning. De konventionella konstruktionernas NVH-beteende bestäms dock huvudsakligen av massan, vilket innebär att tystnad ofta kräver tunga system, vilket leder till ökad energiförbrukning och större utsläpp. Miljötrenderna och den ekonomiska konkurrens som följer av detta har därför begränsat de traditionella (tunga) lösningarna för att förbättra NVH-egenskaperna och gjort lättviktsdesignen svårare. Nya lösningar är nödvändiga för att lösa svårigheten och utmaningen med att kombinera NVH- och lättviktskrav. I den här forskningen genomfördes topologioptimering på en komponent för en ny ledad transportörtransmission (NAHT) för att balansera lättvikts- och NVH-beteende. Den topologioptimerade 3D-modellen fylldes med en icke-homogen gitterstruktur med optimal gittertäthet via storleksoptimering. Gitterstrukturoptimering är en typ av topologioptimering, och det är termen för att beskriva dessa förfaranden. För att tillverka den komplicerade gitterstrukturen krävs additiv tillverkning (eller 3D-utskrift) (efter topologi- och gitterstrukturoptimering). De nya modellerna analyserades med hjälp av finita elementmetoden (FEM), och resultaten av analysen jämfördes med resultaten av de ursprungliga modellerna. Efter jämförelsen erhölls positiva resultat, vilket visar att optimering av topologi och gitterstruktur kan tillämpas vid utformning av komponenter för byggutrustning. Enligt resultaten kan optimering av gitterstrukturen skapa en tillförlitlig lättviktsdesign med bra NVH-beteende. Dessutom har gitterstrukturens organisering och layout en betydande inverkan på den totala prestandan.

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Jáuregui, Sánchez Yessenia. "The nature of noise in single-pixel cameras and their application in imaging through scattering media." Doctoral thesis, Universitat Jaume I, 2019. http://hdl.handle.net/10803/667330.

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Imaging through scattering media has been a longstanding issue in many scientific fields and several optical techniques have emerged to retrieve the information of objects hidden in highly scattering media. Single-pixel imaging (SPI) techniques have proved to be a potential approach for imaging through scattering media. In this context, the objective of this thesis has been to study the nature of noise in SPI and to address the challenge of recovering the image of an object hidden behind a scattering media using visible and NIR light. In particular, we have developed a numerical model of a single-pixel camera (SPC) taking into account the properties of both the incident light and the photodiode. Moreover, we have proposed a novel approach for imaging through scattering media that combines SPI techniques with Fourier spatial filtering. Finally, we have studied the properties of a SPC in reflection configuration for imaging through scattering media. A pesar de los avances logrados en las últimas décadas, las técnicas convencionales de formación de imágenes aún fracasan al intentar adquirir la imagen de un objeto inmerso en un medio turbio. Sin embargo, las técnicas de imagen basadas en luz estructurada y detección con un solo píxel han probado ser una solución alternativa. El objetivo de esta tesis ha sido el estudio de la naturaleza del ruido de estas cámaras de un solo píxel y su aplicación en la formación de imágenes a través de un medio turbio empleando luz visible y radiación infrarroja. En particular, hemos desarrollado un modelo numérico para estas cámaras que tiene en cuenta tanto las propiedades de la iluminación como las del fotodiodo y hemos desarrollado una nueva cámara de un solo píxel basada en filtraje espacial de Fourier que mejora el contraste de las imágenes obtenidas a través de un medio turbio.

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Bony, Guénaëlle. "Contraintes et potentialités naturelles de quelques sites portuaires antiques de Méditerranée et de mer Noire (Fréjus, Ampurias, Kition, Istanbul, Orgamé)." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM3039.

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Il y a 7000 ans BP, la stabilisation du niveau marin a entraîné la formation de deltas. Ces zones deltaïques abritent des milieux aux degrés de protection différents favorables à une activité maritime. Cependant, ces espaces sont soumis à des contraintes naturelles : à l'échelle de la longue durée, l'alluvionnement des deltas entraîne la mobilité des littoraux et le colmatage des milieux portuaires ; à l'échelle de l'événement, les tempêtes, les tsunamis et la mobilité crustale entraînent la destruction, la submersion ou le soulèvement des zones portuaires. Ce travail porte sur l'étude des contraintes et des potentialités environnementales de cinq ports antiques répartis dans le monde Méditerranéen en marge de deltas. L'objectif est d'estimer le poids de ces contraintes sur les sociétés via une approche statistique. Pour quatre des sites d'études, l'alluvionnement est le forçage majeur. A Kition et Orgame, l'impact de l'alluvionnement est indirect. La fermeture des baies marines par l'édification de cordons littoraux crée des environnements lagunaires propices à l'installation de zones portuaires. En revanche, Fréjus et Ampurias sont soumis à un alluvionnement direct qui a rapidement colmaté les bassins. A partir de l'époque romaine et avec l'invention de la pouzzolane, des zones portuaires sont installées en milieu littoral ouvert, comme à Istanbul. Dans un contexte tectoniquement actif, les tsunamis constituent la contrainte majeure opérant sur le port byzantin de Théodose à Istanbul. Un dépôt grossier et chaotique, contenant du matériel marin et archéologique remanié, compose une partie de la séquence stratigraphique de colmatage du bassin et témoigne de ce forçage The stabilization of sea level at 7000 years ago led to the formation of deltaic areas. These areas constituted sheltered environments particularly conducive to maritime activity. However, these areas were also subject to natural constraints for human occupation: at long timescales, high sediment supply to deltaic areas led to significative coastal changes and the infilling of harbour areas; at shorter timescales, high-energy events and crustal mobility led to the destruction, submersion and/or uplift of harbour areas. This work focuses on the study of environmental constraints and potentialities governing five ancient harbours, located on deltaic margins in the Mediterranean. The study aims to semi-qualitatively measure of the weight of these constraints on harbour cities, using statistical approach. High sediment supply is the major natural forcing. At Orgame and Kition, the closure of marine bays by coastal barriers led to the formation of lagoon environments conducive to the installation of harbour areas. Frejus and Ampurias were subject to direct siltation which quickly infilled the harbour basin. The invention of the pozzolan in Roman times means that harbours could be constructed in coastal areas open to the sea and away from river mouths, such as Istanbul harbour. In a tectonically active context, tsunamis are the major constraint acting in the Byzantine harbour of Theodosius in Istanbul. There, the stratigraphic sequence contains a coarse and chaotic deposit composed of reworked marine and archaeological material which demonstrates the societal impacts of such a natural and destructive forcing agent

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Sanmartí, Espinal Marta. "Study of natural nanovesicles carrying olfactory receptors for the development of biosensing platforms." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/286002.

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Natural vesicles produced from genetically engineered cells with tailored membrane receptor composition are promising building blocks for sensing biodevices. This is particularly true for the case of G-protein coupled receptors (GPCRs) present in many sensing processes in cells, whose functionality crucially depends on their lipid environment. Membrane receptors are involved in a variety of biochemical pathways and therefore constitute important targets for therapy and development of new drugs. Bioanalytical platforms and binding assays, using these transmembrane receptors, for drug screening or diagnostic require building well-characterized lipid membrane arrays, acting as supports to prevent protein denaturation during biochip processing. The controlled production of natural vesicles containing GPCRs, their characterization and their reproducible deposition on surfaces are among the outstanding challenges in the road map to realize practical biomolecular devices based on GPCRs. In addition, quantification of the protein receptors in such lipid membrane arrays is a key issue in order to produce reproducible and well-characterized chips. In this thesis we present the production and characterization of membrane nanovesicles (NV) from Saccaromyces Cerevisiae containing heterologously expressed olfactory receptors - a member of the family of GPCRs. We have demonstrated that membrane fractions from yeast cells spontaneously form closed spherical nanovesicles in solution. A simple method to homogenize the size of the nanovesicles to a diameter of around 100 nm at a concentration of more than 1010 nanovesicles mL-1 is also presented. It is also showed that after a genetic engineering process the olfactory receptors of interest were well expressed in the yeast membrane. Furthermore, we report for the first time a novel immunochemical analytical approach for the quantification of transmembrane proteins (i.e. GPCR) in their natural lipid environment. The procedure allows direct determination of tagged receptors (i.e. c-myc tag) without any previous protein purification or extraction steps. The proposed approach uses monoclonal antibodies addressed against the c-myc tag, frequently used in protein expression, on a microplate-based ELISA format with high detectability. The immunochemical method quantifies this tag on proteins or bioreceptors embedded in nanovesicles with detectability in the picomolar range, using protein bioconjugates as reference standards. The applicability of the method is demonstrated through the quantification of the c-myc-olfactory receptors (ORs, c-myc-OR1740 and c-myc-OR7D4) in plasma membrane nanovesicles (NVs). We also show by direct observation with Atomic Force Microscopy that nanovesicles deposit and flatten without rupturing on glass and gold substrates following approximately a diffusive law. We show that on glass surface coverages larger than 20-25% of the substrate can be reproducibly achieved under practical nanovesicle concentrations and reasonable time scales, while keeping to the minimum the presence of background residuals coming from the nanovesicles production process. On the other hand, on functionalized gold substrates surface coverages around 10-15% were achieved. Then, the role of surface chemistry was studied showing that modification of gold substrates indicates a higher affinity of natural nanovesicles for acid modified surfaces as compared to amino or alcohol modified surfaces. Nanovesicles deposition in acid modified gold surfaces and glass have been exploited for the generation of an array of multiple nanovesicles. Present results constitute an important step in the practical realization of biosensor devices based on natural nanovesicles integrating G-protein coupled membrane receptors. When olfactory receptors are genetically expressed in closed vesicles from natural yeast membrane fractions the verification of their capability for capturing specific odorant molecules are critical for the design of artificial noses. Thus, we demonstrated by Surface Plasmon Resonance (SPR) measurements on L1 Biacore chips that the receptors were functional. Despite the fact that the expression of olfactory receptors in nanovesicles is low, a fact that is coherent with the general expression level of GPCRs proteins in cells, the integration in nanovesicles together with a careful choice of the SPR experimental conditions and data analysis allowed us to obtain a concentration-dependent SPR response vs. odorant concentration with a sensitivity of 0.5-1.8RU/micromolar. The selectivity of OR carrying NV towards its specific odorant was proved in cross-check experiments with unspecific odorant molecules and control receptors. These results constitute a proof of concept that ORs embedded in nanovesicles properly respond to odorants and definitely open the perspective to use the surface plasmon resonance technique for the detection of small odorants at concentration in the micromolar range. Vesícules naturals produïes a partir de cèl·lules modificades genèticament són prometedors components de sensat per utilitzar com a detectors en biodispositius. Això és particularment cert en el cas de receptors adjuntats a proteïna G (GPCRs) presents en molts processos cel·lulars, on la seva funcionalitat depèn estrictament del seu entorn lipídic. Els receptors de membrana estan involucrats en una gran varietat de vies bioquímiques i per tant són objectiu d’estudi per teràpia i desenvolupament de nous fàrmacs. Per tant, plataformes bioanalítiques i assajos d’unió receptor-lligand, utilitzant receptors transmembrana, requereixen la construcció de matrius de membranes lipídiques ben caracteritzades, actuant com a suport per evitar la desnaturalització de proteïnes durant el processament del bioxip. En aquesta tesi es presenta la producció i caracterització de nanovesícules de membrana (NV) provinents de cèl·lules de llevat Saccharomyces cerevisiae que contenen receptors olfactius (un membre de la família de GPCRs) heteròlogament expressats a la membrana. Hem demostrat que les fraccions de membrana, a partir de cèl·lules de llevat, en solució formen espontàniament nanovesícules esfèriques tancades. També s’ha demostrat, que després d’un procés de enginyeria genètica els receptors olfactius van ser expressats correctament a la membrana del llevat. També s’ha presentat un mètode simple per homogeneïtzar la mida de les nanovesícules. A més a més, es presenta per primer cop un nou mètode immunoquímic per la quantificació directa de les proteïnes transmembrana (GPCR) en el seu ambient lipídic natural. El mètode utilitza anticossos monoclonals en un assaig basat en ELISA amb alta detectabilitat. L’aplicació del mètode es demostra a través de la quantificació del receptors olfactius OR1740 i OR7D4 expressats en nanovesícules de membrana plasmàtica. També es presenta, mitjançant observació directa amb AFM, com les nanovesícules es depositen i s’aplanen sense trencar-se sobre substrats de vidre i or seguint la llei de difusió. Es demostra com en el cas del vidre els màxims recobriments superficials obtinguts són del 20-25% i en el cas del or funcionalitzat del 10-15%, controlant la concentració de nanovesícules, el temps de depòsit, la presència de residus procedents del procés de producció de les nanovesícules, la química de la superfície, la força iònica del medi, etc. Finalment, s’ha demostrat per SPR que els receptors expressats eren funcionals i que aquesta tècnica òptica permet la detecció de petites molècules, com són els odorants, a les concentracions en el rang micromolar. Els resultats presentats en aquesta tesis contribueixen donant un pas important a la realització de dispositius biosensors basats en nanovesícules naturals que integren receptors de membrana adjuntats a proteïna G.

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Francezon, Nellie. "Valorisation de l'écorce de Picea mariana par la production d'extraits naturels : les extraits aqueux et l'huile essentielle." Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/30953.

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L’épinette noire Picea mariana est une essence abondamment exploitée au Québec pour la qualité de son bois de charpente. Sa transformation par les scieries génère, en conséquence, d’énormes volumes d’écorces résiduelles. Dans un objectif de transformation de la ressource et de conception de produits et systèmes innovants, ce projet de doctorat a permis de développer un procédé de conversion de la biomasse forestière pour la valorisation complète de l’écorce de l’épinette noire, en utilisant des solvants respectueux de l’environnement. Ce procédé intègre deux types d’extractions différentes : l’hydrodistillation et l’extraction à l’eau chaude. Ainsi il produit simultanément trois extraits naturels, l’huile essentielle et l’hydrolat capturant la fragrance de l’épinette et l’extrait aqueux brut riche en polyphénols antioxydants. L’élucidation de la composition chimique de l’huile essentielle et de l’hydrolat d’écorce de l’épinette noire a mis en évidence plus de cinquante composés volatils et aromatiques appartenant à la famille des terpénoïdes. De plus, la fragrance de l’huile essentielle est très différente de celle produite industriellement à partir des aiguilles. Elle pourrait ainsi constituer un nouveau produit pour les secteurs de la parfumerie et des arômes. L’extrait brut aqueux, quant à lui, est riche en polyphénols antioxydants, en tanins et en sucres. Les composés phénoliques de faibles masses moléculaires appartiennent majoritairement à la famille des stilbènes dont les trans-isorhapontine, trans-resvératrol, trans-picéide et transastringine. Deux nouvelles molécules ont également été découvertes dans cet extrait : deux stéréoisomères de stilbènes, appelés picéasides O et P. Dans le but de récupérer ces molécules d’intérêt en plus grande quantité, une optimisation de l’extraction aqueuse a été réalisée pour établir les meilleurs paramètres d’extraction. La température 80 °C et le ratio écorce/eau 50 mg/mL ont été déterminés comme étant les paramètres les plus efficaces pour enrichir l’extrait aqueux en polyphénols d’intérêt, grâce à une approche statistique impliquant la chimiométrie. Ainsi, trois produits à haute valeur ajoutée sont disponibles à partir de l’écorce de l’épinette noire. Mais le plus pertinent au niveau industriel, c’est qu’ils peuvent être extraits simultanément via le procédé intégré dont le développement a permis de valider les rendements et les compositions chimiques tout en garantissant la disponibilité des écorces résiduelles pour la combustion. Ce projet de doctorat permet d’offrir une solution de gestion efficace des coproduits de transformation du bois par le biais d’un procédé vert produisant trois produits naturels à haute valeur ajoutée. Les extraits riches en polyphénols constitueraient de nouveaux ingrédients naturels potentiels pour les secteurs cosmétiques et de santé nutrition, en tant qu’actifs pour la peau ou compléments alimentaires antioxydants. De plus, les molécules d’intérêt thérapeutique comme le resvératrol et ses dérivés identifiés dans l’extrait aqueux seraient de bons candidats pour l’industrie pharmaceutique. Enfin, l’huile essentielle et l’hydrolat pourraient enrichir la palette du parfumeur ou être employés en tant qu’arômes. The transformation of black spruce Picea mariana, abundantly operated for the quality of its lumber in Quebec, generates huge volumes of residual bark in sawmills. With the objective of transforming the resource and designing innovative products and systems, this doctoral project has developed a process for converting forest biomass through the complete conversion of black spruce bark, using eco-friendly solvents. This process incorporating two different types of extractions (hydrodistillation and hot water extraction) simultaneously produces three natural extracts, the essential oil and hydrosol capturing the fragrance of black spruce and the hot water extract enriched with antioxidant polyphenols. The elucidation of the chemical composition of black spruce bark essential oil and hydrosol has revealed more than fifty volatile and aromatic compounds belonging to the terpenoid family. In addition, the fragrance of the essential oil is very different from the one produced industrially from the needles. It could thus constitute a new product for the perfume and aroma sectors. The aqueous crude extract, on the other hand, is rich in antioxidant polyphenols, tannins and sugars. Phenolic compounds of low molecular weight mainly belong to the stilbene family, including trans-isorhapontin, trans-resveratrol, trans-piceide and trans-astringin. Two new molecules have also been discovered in this extract: two stereoisomers of stilbene, called piceasides O and P. In order to optimally recover these molecules of interest, an optimization of the hot water extraction has made it possible to highlight the best extraction parameters. Thanks to a statistical approach involving chemometrics, the temperature 80 °C and the bark/water ratio 50 mg/mL were determined to be the most effective parameters for enriching the aqueous extract with polyphenols of interest. Thus, three high value-added products are extractable from the bark of black spruce. But the most interesting at an industrial level is that they can be extracted simultaneously via the integrated process whose development has validated the yields and chemical compositions while ensuring the availability of residual bark for combustion. This doctoral project offers a solution for an efficient management of co-products of wood processing through a green process, producing three natural products with high added value. The cosmetic and health nutrition sectors, constantly in search of new natural ingredients, may be interested in marketing these extracts as skin actives or as antioxidant dietary supplements. Molecules of therapeutic interest such as resveratrol and its derivatives identified in the aqueous extract could also be used by the pharmaceutical industry. Essential oil and hydrosol could enrich the perfumer's palette or be used as aromas.

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Merini, Luciana Paula. "Modelo de cânula vaginal na endoscopia transluminal por orifícios naturais (NOTES) pelo acesso transvaginal com extração ovariana (NOSE) em éguas hígidas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/168826.

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A técnica cirúrgica endoscópica transluminal por orifícios naturais (NOTES) tem por definição envolver a introdução de um endoscópio no interior da cavidade abdominal através de uma perfuração intencional de uma víscera (p.ex. estômago, reto, vagina) e realizar uma exploração e/ou operação intra-abdominal. A incisão cirúrgica realizada pela técnica de NOTES tem a vantagem de ser utilizada para a retirada da cavidade abdominal de espécimes (NOSE) reseccionadas através de uma laparoscopia padrão ou por NOTES. O presente estudo teve por objetivo verificar a viabilidade da cânula vaginal em realizar o acesso transvaginal para a cavidade abdominal através da técnica de NOTES transvaginal em éguas hígidas posicionadas em estação e avaliar o acesso vaginal como canal de extração de espécimes (NOSE) em éguas submetidas à ovariectomia laparoscópica via flanco. Foram utilizadas 6 éguas hígidas para ambos os procedimentos cirúrgicos. Os animais foram submetidos a jejum alimentar pré-cirúrgico de 24 à 30 horas. Para a sedação utilizou-se cloridrato de detomidina e cloridrato de lidocaína para execução da epidural baixa. A incisão vaginal foi realizada dorsal à cérvix na posição horária de 12 horas utilizando uma cânula vaginal de ponta romba rosqueada e realizada sob visualização indireta através do endoscópio flexível inserido dentro da cânula. A remoção dos ovários via vaginal ocorreu em quatro das seis éguas utilizadas no experimento. Das quatro éguas, três tiveram a necessidade do aumento manual da colpotomia para apreensão manual dos ovários intracavitária e sua remoção. Em dois animais os ovários tiveram de ser seccionados e removidos através do flanco pelo aumento da incisão do canal de trabalho laparoscópico. A execução cirúrgica do acesso à cavidade abdominal via transvaginal e a técnica de extração de espécimes por NOSE submetidas à ovariectomia laparoscópica via flanco é possível de ser realizada em éguas hígidas. The technique of Natural Orifice Transluminal Endoscopic Surgery (NOTES), by definition, concerns the introduction of an endoscope in the abdominal cavity through an intentional perforation of a viscera (for ex., stomach, recto, vagina) and performs an intra-abdominal exploration and/or operation. The surgical incision performed through the NOTES technique has the benefit of being used to remove resected specimens (NOSE) from the abdominal cavity through a standard laparoscopy or through NOTES. The present study had the purpose to check the practicality of the vaginal cannula in performing transvaginal access to the abdominal cavity through the NOTES technique in standing healthy mares and assess the vaginal access as an canal extraction of specimens (NOSE) in mares subjected to laparoscopic ovariectomy. Six healthy mares were used for both surgical procedures. The food was withheld between 24 to 30 hours before surgery. They were sedated with detomidine hydrochloride and to perform the low epidural, lidocaine hydrochloride was used. The vaginal incision was performed dorsally to the cervix at 12 o’clock position using threaded round tip vaginal cannula and performed under indirect viewing through a flexible endoscope inserted in the cannula. The ovaries were removed through the vagina in four of the six mares used in the experiment. From the four mares, three were required to manually increase the colpotomy for manual intracavitary seizure of the ovaries and their removal. In two of the animals, the ovaries had to be cut and removed through the flank, increasing the incision of the laparoscopic working channel. The procedure to create the access to the abdominal cavity through the vagina to perform the NOTES technique and the specimen extraction technique through NOSE subjected to laparoscopic ovariectomy in healthy mares did not demonstrate high difficulties in its execution nor post-surgical complications, confirming the practicality of the two techniques in the equine species.

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Cotton-Gagnon, Anne, and Anne Cotton-Gagnon. "Effets de facteurs naturels et de la coupe de récupération sur la défoliation de la régénération préétablie pendant une épidémie de la tordeuse des bourgeons de l'épinette." Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27901.

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L’épidémie de la tordeuse des bourgeons de l’épinette (TBE) ayant débuté en 2006 au Québec a désormais affecté plus de 7 million d’hectares. Bien que l’abondance et la vigueur de la régénération préétablie soient des facteurs de haute importance concernant la composition et la productivité futures des forêts, très peu d’études ont ciblé la façon dont celles-ci sont affectées par la TBE. La coupe de récupération post-TBE deviendra un enjeu économique majeur en zone boréale et la réduction de son impact passe par une compréhension des processus écologiques affectés par l’épidémie en cours. La présente étude vise à approfondir les connaissances de l’impact d’une épidémie de la TBE et de la coupe de récupération post-TBE sur la défoliation subie par la régénération préétablie de peuplements mixtes de sapin baumier et d’épinette noire. Les objectifs spécifiques sont d’abord d’évaluer l’effet de la hauteur et de l’espèce des tiges de régénération, ainsi que de la composition du peuplement, sur la défoliation subie par la régénération préétablie. Ensuite, d’évaluer l’effet de la coupe de récupération sur cette défoliation. Les résultats démontrent que la hauteur, l’espèce, la composition du peuplement et la coupe de récupération affectent toutes significativement la défoliation subie par la régénération. Les individus plus grands, les tiges de sapin baumier et toutes les tiges se trouvant dans des sapinières subissent davantage de défoliation. La défoliation des tiges d’épinette noire dans les pessières était radicalement plus élevée dans les sites récupérés comparativement aux sites naturels, ce qui pourrait influencer la composition future de ces peuplements. Davantage d’études long-terme sont nécessaires afin de mieux comprendre la dynamique sous la canopée durant une épidémie de la TBE, en particulier dans des peuplements dominés par l’épinette noire, ce qui permettrait une meilleure gestion écosystémique de nos forêts et une diminution leur susceptibilité à la TBE. L’épidémie de la tordeuse des bourgeons de l’épinette (TBE) ayant débuté en 2006 au Québec a désormais affecté plus de 7 million d’hectares. Bien que l’abondance et la vigueur de la régénération préétablie soient des facteurs de haute importance concernant la composition et la productivité futures des forêts, très peu d’études ont ciblé la façon dont celles-ci sont affectées par la TBE. La coupe de récupération post-TBE deviendra un enjeu économique majeur en zone boréale et la réduction de son impact passe par une compréhension des processus écologiques affectés par l’épidémie en cours. La présente étude vise à approfondir les connaissances de l’impact d’une épidémie de la TBE et de la coupe de récupération post-TBE sur la défoliation subie par la régénération préétablie de peuplements mixtes de sapin baumier et d’épinette noire. Les objectifs spécifiques sont d’abord d’évaluer l’effet de la hauteur et de l’espèce des tiges de régénération, ainsi que de la composition du peuplement, sur la défoliation subie par la régénération préétablie. Ensuite, d’évaluer l’effet de la coupe de récupération sur cette défoliation. Les résultats démontrent que la hauteur, l’espèce, la composition du peuplement et la coupe de récupération affectent toutes significativement la défoliation subie par la régénération. Les individus plus grands, les tiges de sapin baumier et toutes les tiges se trouvant dans des sapinières subissent davantage de défoliation. La défoliation des tiges d’épinette noire dans les pessières était radicalement plus élevée dans les sites récupérés comparativement aux sites naturels, ce qui pourrait influencer la composition future de ces peuplements. Davantage d’études long-terme sont nécessaires afin de mieux comprendre la dynamique sous la canopée durant une épidémie de la TBE, en particulier dans des peuplements dominés par l’épinette noire, ce qui permettrait une meilleure gestion écosystémique de nos forêts et une diminution leur susceptibilité à la TBE. Since 2006, the area defoliated by the spruce budworm (SBW) in Quebec has doubled almost every year, and it has now affected more than 7 million hectares. Although advance regeneration abundance and vigor are critical factors determining future forest composition and productivity, very few studies have focused on how they are affected by a SBW outbreak. In the years to come, post-SBW salvage logging will become a major economic issue in boreal forests and reducing its impact involves an understanding of the ecological processes affected by the outbreak in progress. This study aims to determine the impact of SBW outbreaks and of post-outbreak salvage logging on the defoliation sustained by advance regeneration in mixed stands of balsam fir and black spruce. The specific objectives were, first, to assess the effect of regeneration height and species (balsam fir or black spruce), as well as canopy composition, on the defoliation of advance regeneration. Second, to evaluate whether the defoliation sustained by advance regeneration is greater in salvage logged sites or in natural stands of different compositions. Results showed that height and species of regeneration, canopy composition and salvage logging all significantly affected defoliation. Taller advance regeneration, balsam fir advance regeneration, and all regenerating stems in fir-dominated stands sustained more defoliation. Defoliation sustained by black spruce regeneration was much greater in post-outbreak harvested stands than in the understory of natural sites. Harvesting stands with an important component of black spruce regeneration could potentially reduce the future abundance of black spruce, the preferred species for harvesting. Long-term studies are needed to better understand the dynamics in the regeneration layer during a SBW outbreak, particularly in spruce-dominated stands, to conduct better ecosystem-based management and to help reduce the overall susceptibility of our forests. Since 2006, the area defoliated by the spruce budworm (SBW) in Quebec has doubled almost every year, and it has now affected more than 7 million hectares. Although advance regeneration abundance and vigor are critical factors determining future forest composition and productivity, very few studies have focused on how they are affected by a SBW outbreak. In the years to come, post-SBW salvage logging will become a major economic issue in boreal forests and reducing its impact involves an understanding of the ecological processes affected by the outbreak in progress. This study aims to determine the impact of SBW outbreaks and of post-outbreak salvage logging on the defoliation sustained by advance regeneration in mixed stands of balsam fir and black spruce. The specific objectives were, first, to assess the effect of regeneration height and species (balsam fir or black spruce), as well as canopy composition, on the defoliation of advance regeneration. Second, to evaluate whether the defoliation sustained by advance regeneration is greater in salvage logged sites or in natural stands of different compositions. Results showed that height and species of regeneration, canopy composition and salvage logging all significantly affected defoliation. Taller advance regeneration, balsam fir advance regeneration, and all regenerating stems in fir-dominated stands sustained more defoliation. Defoliation sustained by black spruce regeneration was much greater in post-outbreak harvested stands than in the understory of natural sites. Harvesting stands with an important component of black spruce regeneration could potentially reduce the future abundance of black spruce, the preferred species for harvesting. Long-term studies are needed to better understand the dynamics in the regeneration layer during a SBW outbreak, particularly in spruce-dominated stands, to conduct better ecosystem-based management and to help reduce the overall susceptibility of our forests.

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Natal, Augusto Cesar Vassilopoulos. "O amor, a noite, a religiosidade, o povo e a natureza no discurso de Guimarães Rosa." Universidade Presbiteriana Mackenzie, 2014. http://tede.mackenzie.br/jspui/handle/tede/2341.

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Made available in DSpace on 2016-03-15T19:47:31Z (GMT). No. of bitstreams: 1 Augusto Cesar Vassilopoulos Natal.pdf: 13064132 bytes, checksum: 050021ec6d7e9e3f98aef424674cbea4 (MD5) Previous issue date: 2014-02-07 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior From the study of narratives of Brazilian writer João Guimarães Rosa, we attempted to identify, catalog and describe some elements that they turn on their literary discourse. Readings were taken on a considerable part of the author's work, which originated assertions, assumptions and relationships observed in this study. By analyzing rosianos statements, prioritized five highlight relevant essential discursive themes in his speech, which were divided and organized into five themes: "love, night, religion, people and nature." The authors chosen as analytical support to address the love were the Greek philosophers Plato and Aristotle, thinkers Erich Fromm, Benedito Nunes, Arthur Schopenhauer, André Comte- Sponville Sigmund Freud and Carl Gustav Jung, the sociologist Zygmunt Bauman and semiotician Algirdas Greimas. The authors required as analytical support to treat religiosity were the philosopher St. Augustine, the Essayist Elisa Guimarães and two experts in iconography, Jacopo Varazze and Nilza Botelho Megale. The authors adopted as analytical support for crushing the night were the folklorist Luís da Câmara Cascudo, the demonologist Eliphas Lévi and literary critic Massaud Moisés. The authors listed as analytical support to subsidize the axis on the speech of the people were the socio- linguist Dino Preti, sociologist Roger Bastide, the philosopher Jean - Jacques Rousseau, the thinker Antonio Candido, the anthropologist Claude Lévi - Strauss and again the folklorist Luís da Câmara Cascudo. The authors used as analytical support to embrace nature were Heraclitus of Ephesus and Empedocles of Agrigento philosophers and thinkers Humberto Maturana, Francisco Varela, Fritjof Capra and Gaston Bachelard. A partir do estudo de narrativas do escritor brasileiro João Guimarães Rosa, buscou-se identificar, catalogar e descrever alguns elementos que recorressem em seu discurso literário. Foram realizadas leituras acerca de parte considerável da obra do autor, das quais se originaram as asserções, deduções e relações verificadas neste trabalho. Ao analisar os enunciados rosianos, priorizou-se evidenciar cinco temas discursivos essenciais pertinentes em seu discurso, os quais foram divididos e organizados em cinco eixos temáticos: amor, noite, religiosidade, povo e natureza . Os autores escolhidos como suporte analítico para abordar o amor foram os filósofos gregos Platão e Aristóteles, os pensadores Erich Fromm, Benedito Nunes, Arthur Schopenhauer, André Comte-Sponville Sigmund Freud e Carl Gustav Jung, o sociólogo Zygmunt Bauman e o semioticista Algirdas Greimas. Os autores requeridos como suporte analítico para tratar a religiosidade foram o filósofo Santo Agostinho, a ensaísta Elisa Guimarães e dois especialistas em iconografia, Jacopo de Varazze e Nilza Botelho Megale. Os autores adotados como suporte analítico para esmiuçar a noite foram o folclorista Luís da Câmara Cascudo, o demonologista Eliphas Lévi e o crítico literário Massaud Moisés. Os autores elencados como suporte analítico para subsidiar o eixo sobre o discurso do povo foram o sócio-linguista Dino Preti, o sociólogo Roger Bastide, o filósofo Jean-Jacques Rousseau, o pensador Antonio Candido, o antropólogo Claude Lévi-Strauss e, novamente, o folclorista Luís da Câmara Cascudo. Os autores utilizados como suporte analítico para abarcar a natureza foram os filósofos Heráclito de Éfeso e Empédocles de Agrigento e os pensadores Humberto Maturana, Francisco Varela, Fritjof Capra e Gaston Bachelard.

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Dias, Laura Lima. "Análise de abordagens automáticas de anotação semântica para textos ruidosos e seus impactos na similaridade entre vídeos." Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/6473.

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Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-01-29T16:52:29Z No. of bitstreams: 0 Rejected by Adriana Oliveira (adriana.oliveira@ufjf.edu.br), reason: on 2018-01-30T14:50:12Z (GMT) Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-01-30T16:08:06Z No. of bitstreams: 0 Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-03-21T19:26:08Z (GMT) No. of bitstreams: 0 Made available in DSpace on 2018-03-21T19:26:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-08-31 CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Com o acúmulo de informações digitais armazenadas ao longo do tempo, alguns esforços precisam ser aplicados para facilitar a busca e indexação de conteúdos. Recursos como vídeos e áudios, por sua vez, são mais difíceis de serem tratados por mecanismos de busca. A anotação de vídeos é uma forma considerável de resumo do vídeo, busca e classificação. A parcela de vídeos que possui anotações atribuídas pelo próprio autor na maioria das vezes é muito pequena e pouco significativa, e anotar vídeos manualmente é bastante trabalhoso quando trata-se de bases legadas. Por esse motivo, automatizar esse processo tem sido desejado no campo da Recuperação de Informação. Em repositórios de videoaulas, onde a maior parte da informação se concentra na fala do professor, esse processo pode ser realizado através de anotações automáticas de transcritos gerados por sistemas de Reconhecimento Automático de Fala. Contudo, essa técnica produz textos ruidosos, dificultando a tarefa de anotação semântica automática. Entre muitas técnicas de Processamento de Linguagem de Natural utilizadas para anotação, não é trivial a escolha da técnica mais adequada a um determinado cenário, principalmente quando trata-se de anotar textos com ruídos. Essa pesquisa propõe analisar um conjunto de diferentes técnicas utilizadas para anotação automática e verificar o seu impacto em um mesmo cenário, o cenário de similaridade entre vídeos. With the accumulation of digital information stored over time, some efforts need to be applied to facilitate search and indexing of content. Resources such as videos and audios, in turn, are more difficult to handle with by search engines. Video annotation is a considerable form of video summary, search and classification. The share of videos that have annotations attributed by the author most often is very small and not very significant, and annotating videos manually is very laborious when dealing with legacy bases. For this reason, automating this process has been desired in the field of Information Retrieval. In video lecture repositories, where most of the information is focused on the teacher’s speech, this process can be performed through automatic annotations of transcripts gene-rated by Automatic Speech Recognition systems. However, this technique produces noisy texts, making the task of automatic semantic annotation difficult. Among many Natural Language Processing techniques used for annotation, it is not trivial to choose the most appropriate technique for a given scenario, especially when writing annotated texts. This research proposes to analyze a set of different techniques used for automatic annotation and verify their impact in the same scenario, the scenario of similarity between videos.

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Lin, Yangchen. "Macroscopic insights from mechanistic ecological network models in a data void." Thesis, University of Cambridge, 2015. https://www.repository.cam.ac.uk/handle/1810/254976.

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Complexity science has come into the limelight in recent years as the scientific community begins to grapple with higher-order natural phenomena that cannot be fully explained via the behaviour of components at lower levels of organization. Network modeling and analysis, being a powerful tool that can capture the interconnections that embody complex behaviour, has therefore been at the forefront of complexity science. In ecology, the network paradigm is relatively young and there remain limitations in many ecological network studies, such as modeling only one type of species interaction at a time, lack of realistic network structure, or non-inclusion of community dynamics and environmental stochasticity. I introduce bioenergetic network models that bring together for the first time many of the fundamental structures and mechanisms of species interactions present in real ecological communities. I then use these models to address some outstanding questions that are relevant to understanding ecological networks at the systems level rather than at the level of subsets of interactions. Firstly, I find that realistic red-shifted environmental noise, and synchrony of species responses to noise, are associated with increased variability in ecosystem properties, with implications for predictive ecological modeling which usually assumes white noise. Next, I look at simultaneous species extinction and invasion, finding that as their individual impacts increase, their combined impact becomes decreasingly additive. In addition, the greater the impact of extinction or invasion, the lesser their reversibility via reintroduction or eradication of the species in question. For modifications of pairwise species interactions by third-party species, a phenomenon that has so far been studied one interaction at a time, I find that the many interaction modifications that occur concurrently in a community can collectively have systematic effects on total biomass and species evenness. Finally, examining a higher level of organization in the form of compartmentalized networks, I find that the relationship between intercompartment connectivity and the impacts of species decline depends considerably on network topology and whether the consumer-resource functional response is prey- or ratio-dependent. Overall, the results vary considerably across model communities with different parameterizations, underscoring the contingency and context dependence of nature that scientists and policy makers alike should no longer ignore. This work hopes to contribute to a growing multidisciplinary understanding, appreciation and management of complex systems that is fundamentally transforming the modern world and giving us insights on how to live more harmoniously within our environment.

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Buzzi, Adeline. "Nouveaux tests du modèle cosmologique : élaboration et applications." Aix-Marseille 1, 2010. http://www.theses.fr/2010AIX11057.

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Nous disposons aujourd'hui d'un modèle décrivant l'évolution de l'univers sur les grandes échelles, le Modèle Cosmologique. Au cours de cette thèse, nous avons conçu puis appliqué sur les données les plus récentes plusieurs tests originaux de ce modèle. Nous proposons tout d'abord un critère observationnel visant a rejeter un scenario non métrique de l'accélération cosmique. Puis nous proposons une méthode dont le but est de vérifier observationnellement la cohérence de l'un des piliers du Modèle Cosmologique : le Principe Copernicien. Nous estimons quantitativement l'échelle de l'isotropie d'une distribution de galaxies autour de plusieurs observateurs (et obtenons pour cette échelle 150Mpc/h), puis validons ce résultat par le biais d'une comparaison avec le résultat obtenu avec des simulations à N corps. Enfin, nous proposons et appliquons pour la première fois un test géométrique basé sur le principe d'Alcock-Paczynski. Nous analysons les propriétés de symétrie de systèmes binaires de galaxies lointaines, en apportant les corrections nécessaires des vitesses propres de ces dernières. Nous déterminons ainsi les valeurs des paramètres du modèle, et confirmons de façon indépendante le paradigme cosmologique actuel. L'ensemble des tests que nous proposons peuvent être menés sur les données déjà disponibles, et pourront être menés de façon optimale sur les futurs relevés, SNeIa lointaines et grands sondages spectraux de galaxies (EUCLID, BigBOSS) The Cosmological Model describes today the evolution of the universe on large scales. During this thesis, we developed and applied to state-of-art data new cosmological tests. We first propose an observational criterion to reject a non-metric scenario of cosmic acceleration. Then we propose a strategy that aims to validate using galaxy distribution the consistency of one of the pilars of the Cosmological Model : the Copernican Principle. We estimate quantitatively the scale of isotropy of this distribution around different distant observers (and find for this scale 150Mpc/h), and then compare with results obtained using N-body simulations. Finally, we elaborate and then apply for the first time a geometrical test based on the Alcock-Paczynski effect. We analyze the symmetry properties of binary systems of galaxies, and computed the necessary corrections of their proper velocities. We obtain values for the parameters of the model, and confirm independantly the current cosmological paradigm. All the tests we propose can be implemented using available data, and will be optimally implemented using future surveys (SNeIa, redshift surveys of galaxies, such as EUCLID or BigBOSS)

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Koudoro-Parfait, Caroline. "Des IA au service de l'espace littéraire du XIXe siècle : évaluation et analyse des outils de reconnaissance d'entités nommées spatiales." Electronic Thesis or Diss., Sorbonne université, 2025. http://www.theses.fr/2025SORUL012.

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Dans les domaines liés à l'acquisition et à la valorisation des données spatiales, la reconnaissance d'entités nommées (REN ou en anglais NER pour Named Entity Recognition) géographiques peu devenir un point d'entrée à l'analyse littéraire. La tâche de REN appliquée à des corpus de texte littéraires, voit ses résultats s'exprimer, entre autres, sous forme de cartes. La tâche de transcription de l'image (PDF par exemple) en texte, qui est le premier maillon de la chaîne de traitement pour l'acquisition des données textuelles et la constitution des corpus numériques, peut être assurée manuellement ou par utilisation des systèmes de reconnaissance optique de caractère (OCR).Si l'utilisation d'un système OCR permet une plus grande rapidité d'exécution de la tâche, comparativement à une saisie manuelle longue et fastidieuse, force est de constater qu'elle est à l'origine d'erreurs de transcription. Il peut s'agir de bruit ou de silence (ajout, substitution et suppression de caractères). Il en va de même pour les transcriptions manuelles, le bruit et le silence pouvant aussi être de nature sémantique, un terme est remplacé par un autre. Ces erreurs produites par la machine peuvent être répétitives et donc modélisables et corrigeables automatiquement dans les sorties, mais lorsqu'elles sont singulières une routine de correction automatique efficace reste difficile à mettre en place. Pour pallier le problème lié à la qualité des transcriptions OCR et obtenir des textes de meilleure qualité, les utilisateurs mettent en place des stratégies, de nettoyage, coûteuses en temps et en moyen. Néanmoins, on peut se demander dans quelle mesure les erreurs dans la reconnaissance des entités nommées spatiales sont réellement imputables au bruitage des données, et quel est l'impact de ce bruit sur les usages consécutifs de ses données. Nous avons constaté au cours d'une enquête utilisateur menée auprès de chercheurs en Humanités Numériques ou en Traitement Automatique des Langues que nombre d'entre eux utilisent des transcriptions OCR non corrigées pour « sonder » leur corpus et avoir une première vision des grandes tendances à analyser. Mais, ces corpus permettent-ils d'examiner des phénomènes attestés qui donneront lieu à des applications scientifiques viables ? Nous présentons une évaluation de différents outils de REN sur des transcriptions OCR brutes. Afin d'évaluer la robustesse des outils de REN, nous comparons les résultats sur dix œuvres (dans leur version de référence et leur version OCR) issues des collections française, anglaise et portugaise d'ELTeC - European Literary Text Collection, comptant entre 100 et 400 pages chacune. Nous montrons qu'une proportion non négligeable des erreurs est imputable aux modèles, et non aux données, et que, de façon très étonnante, certaines entités sont détectées dans les données bruitées, même lorsqu'elles sont mal orthographiées. Ainsi, ces interférences dans la REN, qui découlent des silences et bruits dans les exploitations des corpus -- certaines entités nommées ne sont pas reconnues, amenant donc du « silence », d'autres sont détectées par erreur, apportant du « bruit » -- ne sont pas simplement inhérentes à la qualité des données en entrée. Si le bruit peut être dépassé (selon plusieurs stratégies : correction, lecture attentive, etc.), le silence fait disparaître de l'information et reste un problème ouvert quant à son impact sur bon nombre d'utilisations postérieures potentielles. Ces travaux de recherches s'appliquent à établir des méthodes pour l'évaluation des systèmes de REN sur des données du monde réel, c'est à dire des données telles que les chercheurs en littérature les acquiers, et s'attache à trouver des stratégies pour assister l'utilisateur i ce dans l'extraction et l'exploration de ces données In fields related to the acquisition and enhancement of spatial data, geographic Named Entity Recognition (NER) can become an entry point for literary analysis. When NER is applied to literary text corpora, its results can be expressed, among other formats, as maps. The task of transcribing images (such as PDFs) into text, which is the first step in the processing chain for acquiring textual data and creating digital corpora, can be done manually or by using Optical Character Recognition (OCR) systems. While the use of an OCR system allows for much faster task execution compared to long and tedious manual entry, it is undeniable that OCR introduces transcription errors. These errors can involve noise or silence (addition, substitution, and deletion of characters). The same applies to manual transcriptions, where noise and silence can also be semantic in nature, with one term being replaced by another.Machine-generated errors can often be repetitive, which means that they can be modeled and automatically corrected in the outputs. However, when they are unique, implementing an effective automatic correction routine remains challenging. To overcome the issue of OCR transcription quality and obtain higher-quality texts, users implement cleaning strategies that are costly in both time and resources. Nevertheless, one might ask to what extent errors in spatial named entity recognition are truly attributable to data noise, and what impact this noise has on the subsequent uses of this data. In a user survey conducted among researchers in Digital Humanities and Natural Language Processing, we observed that many of them use uncorrected OCR transcriptions to “probe” their corpus and gain an initial overview of the major trends to analyze. However, do these corpora allow the examination of attested phenomena that can lead to viable scientific applications? We present an evaluation of various NER tools on raw OCR transcriptions. To assess the robustness of these NER tools, we compare the results on ten books, each comprising between 100 and 400 pages, (in their reference and OCR versions) from the French, English, and Portuguese collections of ELTeC - European Literary Text Collection. We demonstrate that a significant proportion of the errors are attributable to the models and not to the data, and, quite surprisingly, that certain entities are detected in noisy data even when they are misspelled. Thus, these interferences in NER, arising from silences and noise in corpus processing — where some named entities are not recognized, resulting in “silence,” and others are detected in error, introducing “noise” — are not merely inherent to the quality of the input data.While noise can be overcome (through various strategies such as correction, careful reading, etc.), silence results in the loss of information and remains an open issue regarding its impact on many potential future uses. This research aims to establish methods for evaluating NER systems on real-world data, meaning data as it is acquired by literary researchers, and focuses on finding strategies to assist users in the extraction and exploration of this data

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Morchid, Mohamed. "Représentations robustes de documents bruités dans des espaces homogènes." Thesis, Avignon, 2014. http://www.theses.fr/2014AVIG0202/document.

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En recherche d’information, les documents sont le plus souvent considérés comme des "sacs-de-mots". Ce modèle ne tient pas compte de la structure temporelle du document et est sensible aux bruits qui peuvent altérer la forme lexicale. Ces bruits peuvent être produits par différentes sources : forme peu contrôlée des messages des sites de micro-blogging, messages vocaux dont la transcription automatique contient des erreurs, variabilités lexicales et grammaticales dans les forums du Web. . . Le travail présenté dans cette thèse s’intéresse au problème de la représentation de documents issus de sources bruitées.La thèse comporte trois parties dans lesquelles différentes représentations des contenus sont proposées. La première partie compare une représentation classique utilisant la fréquence des mots à une représentation de haut-niveau s’appuyant sur un espace de thèmes. Cette abstraction du contenu permet de limiter l’altération de la forme de surface du document bruité en le représentant par un ensemble de caractéristiques de haut-niveau. Nos expériences confirment que cette projection dans un espace de thèmes permet d’améliorer les résultats obtenus sur diverses tâches de recherche d’information en comparaison d’une représentation plus classique utilisant la fréquence des mots.Le problème majeur d’une telle représentation est qu’elle est fondée sur un espace de thèmes dont les paramètres sont choisis empiriquement.La deuxième partie décrit une nouvelle représentation s’appuyant sur des espaces multiples et permettant de résoudre trois problèmes majeurs : la proximité des sujets traités dans le document, le choix difficile des paramètres du modèle de thèmes ainsi que la robustesse de la représentation. Partant de l’idée qu’une seule représentation des contenus ne peut pas capturer l’ensemble des informations utiles, nous proposons d’augmenter le nombre de vues sur un même document. Cette multiplication des vues permet de générer des observations "artificielles" qui contiennent des fragments de l’information utile. Une première expérience a validé cette approche multi-vues de la représentation de textes bruités. Elle a cependant l’inconvénient d’être très volumineuse,redondante, et de contenir une variabilité additionnelle liée à la diversité des vues. Dans un deuxième temps, nous proposons une méthode s’appuyant sur l’analyse factorielle pour fusionner les vues multiples et obtenir une nouvelle représentation robuste,de dimension réduite, ne contenant que la partie "utile" du document tout en réduisant les variabilités "parasites". Lors d’une tâche de catégorisation de conversations,ce processus de compression a confirmé qu’il permettait d’augmenter la robustesse de la représentation du document bruité.Cependant, lors de l’élaboration des espaces de thèmes, le document reste considéré comme un "sac-de-mots" alors que plusieurs études montrent que la position d’un terme au sein du document est importante. Une représentation tenant compte de cette structure temporelle du document est proposée dans la troisième partie. Cette représentation s’appuie sur les nombres hyper-complexes de dimension appelés quaternions. Nos expériences menées sur une tâche de catégorisation ont montré l’efficacité de cette méthode comparativement aux représentations classiques en "sacs-de-mots" In the Information Retrieval field, documents are usually considered as a "bagof-words". This model does not take into account the temporal structure of thedocument and is sensitive to noises which can alter its lexical form. These noisescan be produced by different sources : uncontrolled form of documents in microbloggingplatforms, automatic transcription of speech documents which are errorprone,lexical and grammatical variabilities in Web forums. . . The work presented inthis thesis addresses issues related to document representations from noisy sources.The thesis consists of three parts in which different representations of content areavailable. The first one compares a classical representation based on a term-frequencyrepresentation to a higher level representation based on a topic space. The abstractionof the document content allows us to limit the alteration of the noisy document byrepresenting its content with a set of high-level features. Our experiments confirm thatmapping a noisy document into a topic space allows us to improve the results obtainedduring different information retrieval tasks compared to a classical approach based onterm frequency. The major problem with such a high-level representation is that it isbased on a space theme whose parameters are chosen empirically.The second part presents a novel representation based on multiple topic spaces thatallow us to solve three main problems : the closeness of the subjects discussed in thedocument, the tricky choice of the "right" values of the topic space parameters and therobustness of the topic-based representation. Based on the idea that a single representationof the contents cannot capture all the relevant information, we propose to increasethe number of views on a single document. This multiplication of views generates "artificial"observations that contain fragments of useful information. The first experimentvalidated the multi-view approach to represent noisy texts. However, it has the disadvantageof being very large and redundant and of containing additional variability associatedwith the diversity of views. In the second step, we propose a method based onfactor analysis to compact the different views and to obtain a new robust representationof low dimension which contains only the informative part of the document whilethe noisy variabilities are compensated. During a dialogue classification task, the compressionprocess confirmed that this compact representation allows us to improve therobustness of noisy document representation.Nonetheless, during the learning process of topic spaces, the document is consideredas a "bag-of-words" while many studies have showed that the word position in a7document is useful. A representation which takes into account the temporal structureof the document based on hyper-complex numbers is proposed in the third part. Thisrepresentation is based on the hyper-complex numbers of dimension four named quaternions.Our experiments on a classification task have showed the effectiveness of theproposed approach compared to a conventional "bag-of-words" representation

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Blondel, Thibaut. "Traçage spatial et temporel des eaux souterraines dans les hydrosystèmes karstiques par les matières organiques dissoutes : expérimentation et application sur les sites du Laboratoire Souterrain à Bas Bruit (LSBB) de Rustrel – Pays d'Apt et de Fontaine de Vaucluse." Phd thesis, Avignon, 2008. https://theses.hal.science/tel-00684295.

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Le principal objectif de ce travail est le développement, l'application et la validation de nouveaux traceurs hydrogéologiques sur la base de signatures spectrales spécifiques des matières organiques dissoutes (MOD) et du suivi de leur évolution dans les hydrosystèmes karstiques méditerranéens. Pour cela, de nombreuses analyses hydrodynamiques et hydrochimiques ont été réalisées, et plusieurs méthodes de caractérisation de la MOD ont été utilisées. Le travail s'est alors fondé sur l'étude de différents niveaux du bassin expérimental de la Fontaine de Vaucluse (sol, épikarst et zone non saturée), grâce à un accès privilégié rendu possible par le Laboratoire Souterrain à Bas Bruit de Rustrel-Pays d'Apt (Vaucluse, France). Un bon traceur hydrogéologique requiert des caractéristiques particulières (solubilité dans l'eau, stabilité, tendance faible à l'adsorption, limite de détection faible et des variations bien identifiables). Les composés organiques correspondant le mieux à ces critères sont des substances dérivées de la décomposition de la lignine. Leurs différentes caractéristiques et leurs faibles concentrations dans l'hydrosystème poussent à utiliser des modes de détection suffisamment sensibles tels que la spectrométrie de fluorescence et la Résonance Paramagnétique Électronique (RPE). L’application conjointe des analyses en RPE et en spectrofluorimétrie sur les lixiviats de sols et les eaux souterraines du LSBB permet de proposer deux protocoles de traçages hydrogéologiques. Le premier concerne la détermination des zones superficielles de sol appartenant au bassin d’alimentation des écoulements suivis. Le second, s'appuyant notamment sur l'évolution et la dynamique des MOD dans l'hydrosystème, correspond au développement de traceurs quantitatifs du temps de transit de l'eau pouvant s’appliquer de manière évènementielle par le marquage d’une période particulière de leur variation, ou en continu permettant ainsi le suivi des variations du temps de transit. Enfin, le rapprochement des résultats obtenus par ces nouveaux traceurs organiques avec ceux d'un traceur isotopique (l'oxygène 18) a permis de tester la validité des calculs du temps de transit, mais aussi de démontrer leur complémentarité The aim of this study is to develop, apply and validate new hydrogeological tracers, based on specific spectral fingerprints of Dissolved Organic Matter (DOM), and a monitoring of their evolution in Mediterranean karstic hydrosystems. Many hydrodynamic and hydrochemical analyses were made, and several DOM characterization methods were used. The basis of this work is therefore the study of different levels of Fontaine de Vaucluse experimental basin (soil, epikarst and unsaturated zone), thanks to a privileged access : the Low-Noise Underground Laboratory of Rustrel - Pays d’Apt (Vaucluse, France). Good hydrogeological tracers require specific characteristics (water solubility, stability, a low tendency to adsorption, a low detection limit and identifiable variations). Organic compounds, corresponding to these criterions at best, are lignin-derived compounds. Their different characteristics and their low concentrations in the hydrosystem drive us to use sensitive enough detection methods, such as fluorescence spectrometry and Electronic Paramagnetic Resonance (EPR). Linked application of EPR and spectrofluorimetric analyses of leachate soil and LSBB groundwater allow to develop two hydrogeological tracing protocols. The first one concerns the determination of upper soil zone, which belongs to monitoring flow catchment area. The second one, using the evolution and the dynamics of DOM in the hydrosystem, corresponds to the development of transit time qualitative tracers, which apply either in an event-driven way by the marking of specific period of their variations, or continuously allowing the monitoring of transit time variations. Finally, the comparison between the results obtained by these new organic tracers and by an isotopic tracer (18 Oxygen) allows to validate transit time calculations and prove their complementarity

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Silva, Nuno Miguel Tavares Costa e. "Phonocardiogram noise detection in realistic environments." Dissertação, 2012. https://repositorio-aberto.up.pt/handle/10216/65307.

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Silva, Nuno Miguel Tavares Costa e. "Phonocardiogram noise detection in realistic environments." Master's thesis, 2012. https://repositorio-aberto.up.pt/handle/10216/65307.

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Camacho, João David Ribeiro. "The use of Gaussian processes in the analysis of stellar noise in exoplanet search." Dissertação, 2017. https://repositorio-aberto.up.pt/handle/10216/107520.

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"Robust Networks: Neural Networks Robust to Quantization Noise and Analog Computation Noise Based on Natural Gradient." Master's thesis, 2019. http://hdl.handle.net/2286/R.I.55679.

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abstract: Deep neural networks (DNNs) have had tremendous success in a variety of statistical learning applications due to their vast expressive power. Most applications run DNNs on the cloud on parallelized architectures. There is a need for for efficient DNN inference on edge with low precision hardware and analog accelerators. To make trained models more robust for this setting, quantization and analog compute noise are modeled as weight space perturbations to DNNs and an information theoretic regularization scheme is used to penalize the KL-divergence between perturbed and unperturbed models. This regularizer has similarities to both natural gradient descent and knowledge distillation, but has the advantage of explicitly promoting the network to and a broader minimum that is robust to weight space perturbations. In addition to the proposed regularization, KL-divergence is directly minimized using knowledge distillation. Initial validation on FashionMNIST and CIFAR10 shows that the information theoretic regularizer and knowledge distillation outperform existing quantization schemes based on the straight through estimator or L2 constrained quantization. Dissertation/Thesis Masters Thesis Computer Engineering 2019

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Camacho, João David Ribeiro. "The use of Gaussian processes in the analysis of stellar noise in exoplanet search." Master's thesis, 2017. https://repositorio-aberto.up.pt/handle/10216/107520.

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Stiewe, Fabian. "The Level of Noise Controls the Efficiency of Natural Selection in Growing Biofilms." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0022-5DA1-B.

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(9759374), Satyabrata Parida. "Neural representations of natural speech in a chinchilla model of noise-induced hearing loss." Thesis, 2020.

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<div>Hearing loss hinders the communication ability of many individuals despite state-of-the-art interventions. Animal models of different hearing-loss etiologies can help improve the clinical outcomes of these interventions; however, several gaps exist. First, translational aspects of animal models are currently limited because anatomically and physiologically specific data obtained from animals are analyzed differently compared to noninvasive evoked responses that can be recorded from humans. Second, we lack a comprehensive understanding of the neural representation of everyday sounds (e.g., naturally spoken speech) in real-life settings (e.g., in background noise). This is even true at the level of the auditory nerve, which is the first bottleneck of auditory information flow to the brain and the first neural site to exhibit crucial effects of hearing-loss. </div><div> </div><div>To address these gaps, we developed a unifying framework that allows direct comparison of invasive spike-train data and noninvasive far-field data in response to stationary and nonstationary sounds. We applied this framework to recordings from single auditory-nerve fibers and frequency-following responses from the scalp of anesthetized chinchillas with either normal hearing or noise-induced mild-moderate hearing loss in response to a speech sentence in noise. Key results for speech coding following hearing loss include: (1) coding deficits for voiced speech manifest as tonotopic distortions without a significant change in driven rate or spike-time precision, (2) linear amplification aimed at countering audiometric threshold shift is insufficient to restore neural activity for low-intensity consonants, (3) susceptibility to background noise increases as a direct result of distorted tonotopic mapping following acoustic trauma, and (4) temporal-place representation of pitch is also degraded. Finally, we developed a noninvasive metric to potentially diagnose distorted tonotopy in humans. These findings help explain the neural origins of common perceptual difficulties that listeners with hearing impairment experience, offer several insights to make hearing-aids more individualized, and highlight the importance of better clinical diagnostics and noise-reduction algorithms. </div>

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Serrano, Luisa Maria. "From ESPRESSO to PLATO: detecting and characterizing Earth-like planets in the presence of stellar noise." Doctoral thesis, 2020. https://hdl.handle.net/10216/127840.

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Serrano, Luisa Maria. "From ESPRESSO to PLATO: detecting and characterizing Earth-like planets in the presence of stellar noise." Tese, 2020. https://hdl.handle.net/10216/127840.

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Dissertations / Theses on the topic 'Natural Noise'

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