Dissertations / Theses on the topic 'Sensory Processes'
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Smith, G. P. "Sensory measurement and control in robotic assembly processes." Thesis, University of Hertfordshire, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384576.
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Hashimoto, Sanae. "Search for receptor mediated processes in Amoeba proteus /." Connect to online version, 2006. http://ada.mtholyoke.edu/setr/websrc/pdfs/www/2006/142.pdf.
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Li, Lin. "Hair cell loss and repair processes in mammalian vestibular sensory epithelia." Thesis, University College London (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266075.
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Sivonen, Päivi Helena. "Event related brain activation in speech perception: from sensory to cognitive processes /." Leipzig : MPI for Human Cognitive and Brain Sciences, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015683097&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Rose, Aimee 1973. "Optimizing the excited state processes of conjugated polymers for improved sensory response." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29321.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2003.Vita.
Includes bibliographical references.
Conjugated polymers exhibit useful and interesting electrical and optical properties. We exploit the wandering excitons produced after photoexcitation for chemosensory applications. By sampling many sites in a polymer film, the excitation has a greater chance to encounter an analyte, such as 2,4,6 trinitrotoluene (TNT), electrostatically poised to induce non-radiative decay. The result is attenuation of the fluorescence signal characteristic of these bright polymers. Because energy migration is responsible for the amplification of sensory response, we sought to augment this migration by integrating chromophores with long-lived excited states into the polymer backbone. The first chromophore we targeted, triphenylene, has a symmetrically-forbidden ground state transition, resulting in a long excited state lifetime. Chapter 2 describes the synthetic incorporation of triphenylene into conjugated polymer backbones, and Chapter 3 details the spectroscopic interrogation of these materials. We demonstrate that lifetime extension is universal to all triphenylene-containing polymers. The longer excited state lifetimes are then correlated with increased energy migration through polarization spectroscopy. In Chapter 4, we extend this paradigm for elongating energy migration in conjugated polymers to several other systems. Unique polymers with symmetric, aromatic chromophores are investigated. These materials allow us to look more rigorously at the variations of effective conjugation pathways and their implications before and after chromophore cyclization. The novel dibenzo[g,p]chrysene, triphenylene and thiophene-based systems afforded us a more complete understanding of the interplay of rigidification, symmetrization, lifetime, and energy migration in conjugated polymers.
(cont.) In the final chapter, we exploit another excited state process in conjugated polymers, stimulated emission, to provide additional amplification of sensory response. We demonstrate that lasing action in optically-pumped conjugated polymer thin film structures can be inhibited by exposure of samples to trace amounts of electron deficient aromatic analytes such as TNT. Analyte exposure introduces non-radiative pathways in the polymer, increasing the lasing threshold. Because lasing is a non-linear phenomenon, it provided two orders of magnitude greater sensitivity to TNT. In combination, we hope that the developments described in this thesis will serve to improve current dernining teclmology in the near future.
by Aimee Rose.
Ph.D.
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Watkins, Shelly S. "Opponent process and nicotine addiction : perpetuation of dependence through negative reinforcement processes /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9963666.
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Hill, S. Kristian. "Maternal perinatal events as predictors of sensory-motor functioning in normal children." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1117100.
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The relationship between perinatal complications and sensory-motor functions was examined. Information from the Maternal Perinatal Scale (MPS) was used to predict factor scores of the Dean Sensory-Motor Battery (DSMB). Participants were 187 normal nonreferred children who were administered the DSMB while their mothers completed the MPS. Using MPS items as predictors, separate stepwise regression analyses for each DSMB factor found that 11 - 16% of variance could be accounted for in sensory-motor performance. At least three MPS items significantly contributed to the prediction of each DSMB factor. Predictors of Sensory and Simple Motor functions (DSMB Factor I) included maternal bleeding during pregnancy, delay between membrane rupture (water break) and onset of labor, and evidence of hypoxia. Evidence of hypoxia, maternal bleeding during pregnancy, and delay between water break and labor onset were predictive of Motor and Complex Sensory functions (DSMB Factor II). In addition, gender of the child joined maternal bleeding during pregnancy, amount of swelling during pregnancy, and mother's height in predicting Subcortical Motor functions (DSMB Factor III). Additional analyses using a canonical correlation confirmed the results of the regression analyses. A linear composite of sensory and motor variables was primarily defined by DSMB factors I and II. The linear composite of perinatal information was defined primarily by the same items that emerged as significant predictors of sensorymotor functions in the regression analyses. Most notably, a redundancy analysis indicated that about 20% of variance in DSMB factor scores could be accounted for by a linear composite of perinatal information. In general, sensory-motor performance decreased as severity of perinatal complications increased. Results were discussed in terms of the implications of using a normal non-referred population. More importantly, the present data suggested the possibility that 1) the relationship between perinatal complications and sensory-motor functions may exist on a continuum rather than the dichotomous diagnosis/no diagnosis, and 2) the synergistic influence of multiple perinatal complications may contribute to the manifestation of clinically significant behaviors. The role of sensory-motor functions as a foundation for more complex behaviors is also discussed.Department of Educational Psychology
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Felice, Renee Jacqueline. "Sensory and Physical Assessment of Microbiologically Safe Culinary Processes for Fish and Shellfish." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/42494.
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Numerous food-borne illnesses are associated with fish and shellfish annually due to consumers choosing to eat seafood raw or undercooked and consumers not properly handling and preparing seafood. The 2009 FDA Food Code suggests intact fish and shellfish should be cooked to an internal temperature of 63°C to target Salmonella spp. Selected fish and shellfish were cooked to 64°C ± 1 and 74°C ± 1 and evaluated for consumer acceptability, characteristics of doneness at temperature endpoints, and physical changes of texture (TPA, KSC, and WB), color, and cook loss. Temperature endpoints represented the recommended internal temperature and ten degrees higher to increase lethality of Salmonella spp. Differences (p < 0.05) in texture were determined among the methods and products tested. However, consumer acceptability (n = 50) for fish and shellfish products (salmon: baked, poached; tilapia: baked, pan-fried; and shrimp: boiled) cooked to 64°C ± 1 and 74°C ± 1 were liked equally (p > 0.05), with mean hedonic scores falling between 6 (like slightly) and 7 (like moderately). A trained descriptive panel (n = 7) reviewed visual and non-oral texture indicators of doneness to distinguish 64°C ± 1 and 74°C ± 1. Firmness and shape of shrimp, separation between muscle flakes and fillet edge color of baked tilapia, and firmness and edge color of the fillet for baked salmon were identified as indicators to determine doneness. Overall, 74°C could be recommended as the internal temperature for cooking fish/shellfish such as salmon, tilapia, and shrimp without diminishing eating quality or acceptability.Master of Science in Life Sciences
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Ronca, April E. "The effects of decerebration prior to maturation: species-typical behavior, sensory processes, and learning /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487329662146174.
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Fogt, Nicklaus F. "The relationship between motor and sensory processes in the fusion of disparate retinal images /." The Ohio State University, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487933648650302.
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Hardy, Dallin Max. "Sensory Acceptability and Nutrient Stability in Micronutrient-Fortified Soymilk Prepared in Small-Scale Batch Processes." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/8284.
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Fortified and unfortified soymilk were produced from the same production batches for comparative evaluation. Fortification included a comprehensive array of micronutrients of interest to community and humanitarian nutrition programs. The effects of time after fortification prior to cooling, cooling method, and light or dark refrigerated storage on the stability of 5 vitamins (vitamin A, vitamin C, thiamine, riboflavin, and folate) were investigated for both fortified and unfortified soymilk. Significant vitamin C loss (6%) and mild vitamin A isomerization occurred while soymilk was hot immediately following fortification. Cooling bottled soymilk in an ambient water bath or ice water bath made no difference in the levels of any of the vitamins measured. Significant loss of riboflavin (18%) and significant vitamin A isomerization to cis isomers other than 13-cis, resulting in loss of bioactivity, occurred during 12 days of light-exposed refrigerated storage. An increase of 13-cis isomer was observed in dark refrigerated storage but with no significant loss of vitamin A bioactivity. No significant degradation of any other vitamins occurred during 12 days of dark refrigerated storage. Sensory evaluation by a panel of youth and children revealed no significant preferences between fortified and unfortified soymilk excepting colour, for which property there was a slight preference for unfortified soymilk. Acceptable vitamin stability and sensory characteristics can be achieved in comprehensively fortified soymilk produced in small-scale batch processes with appropriate management of production and storage conditions.
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Hashmi, Fiza. "EFFECTS OF BRAIN-DERIVED NEUROTROPHIC FACTOR AND ITS SIGNALING PATHWAY ON SENSORY NEURONAL ACTIVATION DURING COLITIS." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3980.
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Visceral hypersensitivity is the heightened response to sensory stimuli. Visceral sensations are transmitted through primary afferent neurons in the dorsal root ganglion (DRG) and the sensitization of the neural pathway leads to modification in spinal ascending and descending neurons. The aim of this investigation is to determine the effects of brain-derived neurotrophic factor (BDNF) and its signaling pathway on sensory neuronal activation during colitis. In order to evaluate this, levels of calcitonin-gene related peptide (CGRP), a neuropeptide marker for nociceptive transmission, and phosphorylated cAMP-response element binding protein (pCREB), a molecular switch in neuronal plasticity, were studied in response to BDNF in vivo and in vitro. Colitis caused an increase in the levels of CGRP and pCREB in thoracolumbar DRG, which was attenuated by BDNF neutralizing antibody and PLC inhibitor, U73122, but not PI3K inhibitor, LY294002. BDNF-induced CGRP expression and CREB activation in DRG culture was also blocked by PLC inhibitor, U73122, but not PI3K inhibitor, LY294002, or MEK kinase inhibitor, PD98059. These results suggest a unique signaling pathway, i.e. the PLC-γ pathway, is mediating BDNF action on sensory neuronal activation during colitis.
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Dierkes, Kai. "Nonlinear amplification by active sensory hair bundles." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-61714.
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The human sense of hearing is characterized by its exquisite sensitivity, sharp frequency selectivity, and wide dynamic range. These features depend on an active process that in the inner ear boosts vibrations evoked by auditory stimuli. Spontaneous otoacoustic emissions constitute a demonstrative manifestation of this physiologically vulnerable mechanism. In the cochlea, sensory hair bundles transduce sound-induced vibrations into neural signals. Hair bundles can power mechanical movements of their tip, oscillate spontaneously, and operate as tuned nonlinear amplifiers of weak periodic stimuli. Active hair-bundle motility constitutes a promising candidate with respect to the biophysical implementation of the active process underlying human hearing.
The responsiveness of isolated hair bundles, however, is seriously hampered by intrinsic fluctuations. In this thesis, we present theoretical and experimental results concerning the noise-imposed limitations of nonlinear amplification by active sensory hair bundles. We analyze the effect of noise within the framework of a stochastic description of hair-bundle dynamics and relate our findings to generic aspects of the stochastic dynamics of oscillatory systems.
Hair bundles in vivo are often elastically coupled by overlying gelatinous membranes. In addition to theoretical results concerning the dynamics of elastically coupled hair bundles, we report on an experimental study. We have interfaced dynamic force clamp performed on a hair bundle from the sacculus of the bullfrog with real-time stochastic simulations of hair-bundle dynamics. By means of this setup, we could couple a hair bundle to two virtual neighbors, called cyber clones. Our theoretical and experimental work shows that elastic coupling leads to an effective noise reduction. Coupled hair bundles exhibit an increased coherence of spontaneous oscillations and an enhanced amplification gain. We therefore argue that elastic coupling by overlying membranes constitutes a morphological specialization for reducing the detrimental effect of intrinsic fluctuations.
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Jirikowic, Tracy L. "Sensory processing and integration and children with alcohol-related diognoses : an exploratory analysis /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/7893.
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Öhlund, Emma, and Anna Thorsell. "Iögonfallande layout & känsloväckande stimuli : En studie om modebutikers fysiska upplägg och dess påverkan på konsumentbeteende och köpbeslut, ur ett företagsperspektiv." Thesis, Södertörns högskola, Institutionen för samhällsvetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-26298.
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Denna studie har som syfte att förklara och ge en ökad förståelse för hur utvalda företag i modebranschen arbetar med det fysiska upplägget i butiker, genom bland annat atmosfär, sinnesstimuli och visuell merchandising. Samt vilken påverkan upplägget kan ha på konsumenters köpbeslutsprocesser och därmed även uppfattningen om varumärket. Sex intervjuer med olika företag har gett kvalitativa data som sedan analyserats mot varandra utifrån studiens teoretiska referensram. Resultat visar på att de studerade företagen inte planerar sin butiksyta beroende på teorier om konsumentbeteende och sinnesmarknadsföring. Utan istället planeras ytan beroende på varumärke och positionering, vilket skiljer sig åt beroende på företag. Att förmedla en känsla och att ge ett helhetsintryck med hjälp av upplägget är viktigt och baseras på hur butikerna vill att varumärket ska uppfattas, vilket sedan påverkar köpbeslutsprocessen då det avgör om kunderna väljer att konsumera i butiken eller inte. En lyckad planering av butiksytan för de studerade företagen, grundar sig därmed inte på hur väl ytan planeras utifrån tidigare forskning om sinnesmarknadsföring och visuell merchandising, utan hur bra den planeras utifrån varumärket.This study aims to describe and to give greater understanding of how selected companies in the fashion industry works with the physical layout of stores, including the use of atmosphere, sensory stimuli and visual merchandising. Also what impact the layout can have on consumers buying process and the perception of the brand. Six interviews with different companies gave qualitative data that was analyzed together and against each other, based on the theoretical framework of the study. The result shows that the selected companies do not plan the layout based on theories of consumer behavior or sensory marketing. Instead the layout is planned based on the brand and the positioning the company works for, which differentiates itself based on what company it is. To convey a feeling and to give an overall impression of the brand with the help of layout is important, and it is based on how the companies want the brand to be perceived. This then affects the buying process because it determines if the customers choses to consume in the store or not. A successful planning of the layout, for the companies in the study, is therefore not based on how well it matches with recent research in the field, but how well it is matched based on the brand only.
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Penedo, José Luis Marques. "Estudo longitudinal de liderança e clima motivacional percepcionado por ginastas de classes representativas." Master's thesis, Instituições portuguesas -- UTL-Universidade Técnica de Lisboa -- -Faculdade de Motricidade Humana, 2000. http://dited.bn.pt:80/29324.
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Armstrong, Michael G. "Effect of zymosan-induced peritonitis on the expression of substance P in primary sensory neurons and spinal nerve processes." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/honors/328.
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Macrophages and other cells of the innate immune system recognize foreign particles that could be potentially dangerous and respond by initiating an inflammatory response. The biologically active chemical mediators of this response called pro-inflammatory cytokines are produced in various myeloid derived immune cells and can affect other cells of the body. Interleukin-1β, a pro-inflammatory cytokine, has been shown to have direct effects on dorsal root ganglion (DRG) cell bodies including the upregulation and direct release of a nociceptive neurotransmitter called substance P (SP). Using a zymosan-induced model of systemic inflammation, we hypothesized that murine DRG neurons and the nerve processes associated with them in the dorsal horn of the spinal cord (SC) at the L1 level will show an upregulation of SP expression in response to inflammation in the peritoneum. Experimental mice were treated with a zymosan suspension (500mg/kg, intraperitoneal injection), and control mice received sterile filtered solution (intraperitoneal injection). Both DRG and SC specimens were collected after in situ fixation and subjected to immunofluorescence staining to label SP. Using confocal microscopy, fluorescence microscopy, and image analysis software this expression of SP was quantified and compared. In both tissue specimen groups, an increase in SP expression was discovered in zymosan treated mice. The exact cause of this increase was not specifically determined in this experiment. This experiment provided valuable insight about how a systemic inflammatory response can affect sensory nerve function. Successful methods for further experimentation were identified and information about the zymosan model of inflammation was obtained
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Woodard, William Bryan. "The computer as a medium for art : aesthetics and the processes of mind." Connect to resource, 1985. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1134055426.
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Lewis, Morris N. "Construct validity of the Dean-Woodcock Neuropsychological Assessment System Sensory Motor Battery : an exploratory factor analysis." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1115714.
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The purpose of this study was to add to the body of psychometric evidence underlying the Dean-Woodcock Sensory Motor Battery (DWSMB) and the theory of sensory motor functioning. Secondly, this study added to the body of literature concerning the role of both cortical and subcortical areas of the brain in motor functioning.The DWSMB is a new battery designed to meet the emerging trends in neuropsychology. It combines the qualitative functionality of the sensory and motor tests used by clinical neurologists with the quantitative, performance-driven sensory motor tests found in traditional neuropsychological assessment batteries. The DWSMB consists of eight tests of sensory functions, seven tests of cortical motor functions, and three tests of subcortical motor functions.A population sample of 441 participants were administered the DWSMB, 340 of which had no reported neurological or psychiatric history. These data were analyzed using an exploratory factor analysis to determine the number of constructs underlying the DWSMB. The study found three factors: a Complex Sensory Motor Factor, a Simple Sensory Factor, and a Subcortical Motor Factor. The three constructs found in this study provided empirical support for the underlying theory of the DWSMB, which will allow neuropsychologists to make inferences about the resulting scores.Department of Educational Psychology
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Freitas, Renata Oliveira Teixeira de. "Repensando o design: estratégias para uma comunicação plurissensorial." Pontifícia Universidade Católica de São Paulo, 2014. https://tede2.pucsp.br/handle/handle/4646.
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Previous issue date: 2014-08-29Conselho Nacional de Desenvolvimento Científico e Tecnológico
This thesis can be included in the field of communication research and aims to reflect on contemporary design based on the possible contributions of the body s multisensory capacities. As the mediator between the informational codes of culture and man s perceptive and cognitive mechanisms, the design activity exerts an undeniable influence and impact on the construction of society. As part of a hyperconnected context, nourished by culture and by the tools of the new media and technologies, design deals with new creation, production, integration and value generation dynamics, as well as the new demands and urgencies of social and environmental co-existence, which require new project approaches. In these terms, multisensory analysis can contribute valuable tools for research development and design practice. The working methodology consisted of mapping out projects from different knowledge domains, such as art, medicine, engineering, technology, business and design itself, in an attempt to understand the distinct forms of action and exploration of the body s sensory communication. This research was undertaken based on theories that dialog with the critique of creation processes of Salles (2006), the questions of signs and the meaning of the semiotic base of Sebeok (1991) and Colapietro (2003), and with the complexity studies of Morin (2005). The discussions relating to communication systems and the contemporary market are supported by Shirky (2010), Lazzarato and Negri (2001), and Rifkin (2014). As far as the cognitive studies and theories of the body are concerned, the works of Nicolelis (2011) and Greiner (2005, 2010) were consulted. When referring to the design and innovation area, we turned to Manzini (2008), Margolin and Buchanan (1995), Brown (2010), Bonsiepe (2011ab), and Thackara (2008). The results of this research showed that knowledge of and investigation into these potentialities can supply project activation strategies, creative resources and means of interaction between people and products, spaces and services, contributing towards a projective action, that is more innovative, sustainable and coherent with the urgencies of the historical and cultural context, as well as promoting positive impacts on the systemic progression scale
A presente tese insere-se no universo das pesquisas da comunicação e tem como propósito refletir sobre o design contemporâneo a partir das possíveis contribuições das capacidades plurissensoriais do corpo. Como mediador entre os códigos informacionais da cultura e os mecanismos perceptivos e cognitivos do homem, a atividade do design exerce indiscutível influência e impacto na construção da sociedade. Inserido em um contexto hiperconectado, nutrido pela cultura e pelas ferramentas das novas mídias e tecnologias, o design lida com novas dinâmicas de criação, produção, interação e geração de valor, além de novas demandas e urgências de convívio social e ambiental que exigem novas abordagens projetuais. Nesse sentido, a exploração plurissensorial pode contribuir com ferramentas válidas para o desenvolvimento da pesquisa e prática do design. Como metodologia de trabalho, foi feito um mapeamento de projetos de diferentes domínios do conhecimento, tais como arte, medicina, engenharia, tecnologia, negócios e o próprio design, por meio dos quais se buscou compreender as distintas formas de ação e exploração da comunicação sensorial do corpo. A pesquisa foi articulada a partir de teorias que dialogam com a crítica de processos de criação de Salles (2006), com as questões do signo e da significação de base semiótica de Sebeok (1991) e Colapietro (2003), e com os estudos da complexidade de Morin (2005). Para embasar as discussões referentes aos sistemas de comunicação e ao mercado contemporâneo, adotamos Shirky (2010), Lazzarato e Negri (2001) e Rifkin (2014). Em relação aos estudos cognitivos e às teorias do corpo, foram consultados os trabalhos de Nicolelis (2011) e Greiner (2005, 2010). E para as referências da área de design e inovação, recorremos a Manzini (2008), Margolin e Buchanan (1995), Brown (2010), Bonsiepe (2011ab) e Thackara (2008). Como resultado da pesquisa, observou-se que o conhecimento e investigação dessas potencialidades pode fornecer estratégias de ativação projetual, recursos criativos e meios de interação entre as pessoas e os produtos, espaços e serviços, contribuindo para uma ação projetiva mais inovadora, sustentável e coerente com as urgências do contexto histórico-cultural, além de promover impactos positivos em escala de progressão sistêmica
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Brondi-Mendes, Juliana Zara 1988. "Percepção do consumidor brasileiro em relação a queijo frescal com reduzido teor de gordura." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255803.
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Orientadores: Walkíria Hanada Viotto, Jorge Hanada ViottoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Nos últimos anos, o mercado de produtos light vem se expandindo graças a um segmento de consumidores preocupados com a qualidade de vida e saúde. O mercado dos lácteos com reduzido teor de gordura está na liderança entre os produtos light mais procurados. Assim, este estudo teve por objetivo avaliar os motivos que influenciam na decisão de compra de queijos com reduzido teor de gordura tanto quanto compreender as razões em não consumi-los e avaliar a composição físico-química, perfil de textura, mobilidade de água por ressonância magnética nuclear de baixo campo e aceitação de diferentes amostras comerciais de queijo frescal light disponíveis no mercado a partir dos processos de fabricação tradicional, acidificação direta e ultrafiltração. Análise conjunta foi a ferramenta utilizada para tentar entender a estrutura de preferência dos consumidores de queijo frescal light, ou seja, compreender a complexidade do processo de escolha e decisão de compra do consumidor. Na primeira fase, caracterizada pelas análises laboratoriais, foi verificado a diferença na composição entre as diferentes fabricações de queijo frescal light, sendo os ultrafiltrados os queijos mais macios, de maior umidade e consequentemente menor de teor de gordura e proteína total. Os resultados de ressonância magnética nuclear revelaram o comportamento da água quanto ao seu estado (livre ou imobilizado) para todas as amostras. Na segunda fase, um questionário sócio demográfico e sobre hábitos de compra foi aplicado a 151 consumidores de queijos light revelando que os principais consumidores são pessoas acima dos 40 anos com alto poder aquisitivo, preocupados em manter hábitos mais saudáveis. Por outro lado, falta de hábito foi a principal razão alegada em não consumir queijos light. A análise conjunta revelou que os consumidores consideram mais importante a textura desses queijos, seguido do tamanho da porção e alegação nutricional. Dentre os níveis de cada fator, queijo fresco de consistência firme, porção individual, light com 40% menos gordura, foram os que tiveram maior preferência. De maneira geral, todos os processos de fabricação de queijo fresco light avaliados foram bem aceitos, com média em torno de 6-7 para aceitação global
Abstract: In recent years, the light products market is expanding due to a segment of consumers concerned about the quality of life and health. The reduced fat dairy market is in the lead among the most sought light products. This study aimed to evaluate the reasons that influence the buying decision of reduced fat content cheeses as well as to understand the reasons not to consume them and evaluate the physical and chemical composition, texture profile analysis, mobility of water by low-field nuclear magnetic resonance and acceptance of different commercial samples of light fresh chesse available in the market from traditional manufacture processes, direct acidification and ultrafiltration. Conjoint analysis was the tool used to understand the consumer preference structure of light fresh cheese, thus, understand the complexity of the process of choosing and consumer buying decision. In the first phase, characterized by laboratory analysis, it was found that the difference in composition between different light fresh cheese manufacturing processes, being the ultrafiltered cheeses the softer cheeses, of high moisture and consequently lower fat content and total protein. The results of nuclear magnetic resonance showed the water behavior regarding to its state (free or immobilized) for all samples. In the second phase, a demographic and shopping habits questionnaire was applied to 151 consumers of light cheeses showing that the main consumers are people over 40 years old with the higher income, concerned about maintaining healthier habits. On the other hand, the lack of habit was the main reason reported at not consume light cheeses. The conjoint analysis showed that consumers consider most important texture of these cheeses, followed by the portion size nutritional claim. Among the levels of each factor, fresh cheese of firm consistence, individual portion and light with 40% less fat, were the ones who had higher preference. In general, all manufacturing process of light fresh cheese evaluated were well accepted, averaging around 6-7 for global acceptance
Mestrado
Tecnologia de Alimentos
Mestra em Tecnologia de Alimentos
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Sobrosa, José Francisco Gomes. "Comportamentos de liderança e objectivos de realização no andebol-estudo em atletas e treinadores do desporto escolar e do desporto federado." Master's thesis, Instituições portuguesas -- UP-Universidade do Porto -- -Faculdade de Ciências do Desporto e de Educação Física, 2002. http://dited.bn.pt:80/29595.
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Batista, Luís Paulo Pereira. "Estudo descritivo-exploratório de um grupo desportivo-em torno da análise da coesão grupal e do desenvolvimento pessoal." Master's thesis, Instituições portuguesas -- UTL-Universidade Técnica de Lisboa -- -Faculdade de Motricidade Humana, 1999. http://dited.bn.pt:80/29036.
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Gomes, Carolina Lugnani. "Impact of end-point temperature of different heat transfer processes in sensory profile of beef strip loin steaks = Impacto da temperatura final interna em diferentes processos de transferênncia de calor no perfil sensorial de contrafilé bovino." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254241.
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Orientador: Helena Maria Andre BoliniTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Dois métodos de cocção (forno e chapa) e três temperaturas internas finais (65, 71 e 77°C) foram aplicados em contrafilé bovino (m. longissimus lumborum), com o objetivo de avaliar qual dos procedimentos proporciona a obtenção de um produto com perfil sensorial descritivo superior em relação à qualidade sensorial. As amostras de contrafilé, porção compreendida da 12º costela e a 2º vértebra lombar, de meias carcaças esquerdas de bovinos da raça Angus, da mesma idade e acabamento de gordura, foram coletadas e congeladas (-20ºC). Cada peça foi cortada em seis bifes de 2.54 cm, que foram embalados a vácuo e mantidos congelados. Os bifes foram distribuídos em seis tratamentos. Para a cocção, os bifes foram descongelados a 4°C por 24 horas antes das análises. As temperaturas internas foram monitoradas por meio de termopares inseridos no centro geométrico de cada bife. Para a perda de peso por cocção, houve interação significativa do método de cocção X temperatura interna final (p=0.002). O aumento da temperatura aumentou constantemente as perdas por cocção em ambos os métodos de cocção, de 65ºC para 77ºC. A 65ºC e 71ºC as perdas por cocção foram similares entre forno e chapa, enquanto a 77ºC, as amostras assadas no forno tiveram as maiores perdas, provavelmente devido ao longo tempo de preparo. Para a força de cisalhamento, não houve interação do método de cocção X temperatura interna final (p=0.54). Os bifes preparados a 65°C e 71ºC tiveram menores valores de WBSF (p<0,05), enquanto que aqueles preparados a 77°C tiveram valores maiores (p<0,05). Na análise de aceitação, a aparência, o aroma e o sabor tiveram maior aceitação nas amostras preparadas no forno elétrico em temperaturas mais altas, entretanto a maciez e a suculência tiveram maior aceitação nas amostras preparadas em temperaturas mais baixas, independente do método de cocção. Os bifes grelhados na chapa elétrica a 65°C foram melhores, porque proporcionaram a obtenção de uma amostra com aceitação significativamente superior em relação a todas as características sensoriais analisadas. Na Análise Descritiva Quantitativa, os bifes do forno e da chapa a 65°C foram principalmente caracterizados pelos atributos de aroma e sabor de sangue, sabor metálico, suculência, maciez, suculência aparente e cor interna vermelha. Na análise tempo-intensidade, a Imáx do estímulo maciez e suculência foi significativamente maior (p<0,05) no forno elétrico em relação à chapa elétrica. E em relação às temperaturas a Imáx das amostras submetidas a 65 e 71ºC não diferiram (p>0,05), mas diferiram (p<0,05) das amostras a 77ºC. O Ttot não foi diferente (p>0,05) para as amostras nos métodos de cocção e nas temperaturas internas finais para os estímulos de maciez e suculência. Portanto sugere-se que as diferenças encontradas pelos assessores na maciez e suculência das amostras, foram percebidas somente a primeira mordida (Imáx). E durante a mastigação até a fase de deglutição (Ttot) não variaram, indicando que as amostras permaneceram igualmente homogêneas em relação aos dois atributos após a primeira mordida
Abstract: Two cooking methods (oven and griddles) and three end-point temperatures (65, 71 and 77°C) were applied in beef strip loin (m. longissimus lumborum), to assess which of the procedures provides a product with superior descriptive sensory profile in order to the sensory quality. Strip loin samples with the similar degree of fat thickness from the 12th rib to the second lumbar vertebra of the left side of the carcass of similarly age Angus steers were collected and frozen (-20ºC). Each piece was cut into six 2.54 cm thick steaks. The steaks remained vacuum packed and frozen. For cooking, the steaks were thawed at 4°C for 24 hours. The internal temperatures were monitored by thermocouples inserted in the geometric center of each steak. The interaction between cooking method and end-point temperature had a significant (P=0.002) impact on cooking loss. The increasing end-point temperature, constantly increase levels of cooking loss in both cooking methods, from 65ºC to 77ºC. At 65ºC and 71ºC the cooking loss were similar between oven and griddle, while at 77ºC the oven had the great loss, probably due to the long cooking. The interaction between cooking method and end-point temperature did not significantly impact (P=0.54) shear force. The steaks prepared at 65°C and 71ºC had lower (P<0.05) shear force values, while those prepared at 77°C had higher values (P<0.05). In acceptance analysis of appearance, aroma and flavor, samples cooked in electric oven, at higher temperatures, had the greater acceptance, however the tenderness and juiciness had greater acceptance in samples prepared at lower temperatures, regardless the method of cooking. Steaks grilled on the counter-top griddles at 65°C yielded a sample with a significantly greater acceptability in terms of all of the sensory characteristics analyzed. For Descriptive Quantitative Analysis, steaks prepared in oven and griddles at 65°C were mainly characterized by a blood aroma and flavor, a metallic flavor, juiciness, initial tenderness, apparent juiciness and internal red color. In the time-intensity analysis, the Imax values for tenderness and juiciness stimuli was higher (P<0.05) for the samples subjected to the electric oven as compared to the electric griddles. Regarding the temperatures, although the Imax for tenderness and juiciness of the samples subjected to temperatures of 65 and 71ºC were not different (P>0.05), it differed (P<0.05) from the samples at 77ºC. The Ttot value was not different (P>0.05) for both cooking methods and end-point temperatures in relation to the stimuli tenderness and juiciness. It can be suggested that the differences on tenderness and juiciness found by the assessors were noted only at first bite (Imax). Perception of tenderness and juiciness during chewing to swallowing (Ttot) did not vary, indicating that the samples remained homogeneous for both attributes after the first bite
Doutorado
Consumo e Qualidade de Alimentos
Doutora em Alimentos e Nutrição
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Lecuelle, Guillaume. "Analyse et modélisation de la Dominance Temporelle des Sensations à l'aide de processus stochastiques." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCK031/document.
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La Dominance Temporelle des Sensations (DTS) est une méthode d’analyse sensorielle qui mesure la perception temporelle d’un produit au cours de sa dégustation. Pour un panéliste, la DTS consiste à choisir parmi une liste de descripteurs lequel est dominant à chaque instant. Ce travail a pour but la modélisation des données DTS à l’aide de processus stochastiques et propose d’utiliser les processus semi-markoviens (PSM), une généralisation des chaînes de Markov qui permet de modéliser librement les durées de dominance. Le modèle obtenu peut être utilisé pour comparer des échantillons DTS en réalisant un rapport de vraisemblance. Étant donné que les probabilités de transition entre les descripteurs peuvent dépendre du temps, nous proposons d’utiliser des modèles différents par période et nous proposons un algorithme pour déterminer le nombre et les frontières de ces périodes de manière optimale. Le modèle est représenté sous forme d’un graphe montrant les transitions entre descripteurs les plus observées. Finalement, ce travail introduit les modèles de mélange de processus semi-markoviens afin de segmenter le panel en fonction des différences de perception interindividuelles.Les méthodes développées sont appliquées à des jeux de données DTS variés : chocolats, fromages frais et Goudas. Les résultats montrent que la modélisation par un PSM apporte de nouvelles informations sur la perception temporelle, en particulier sur la variabilité de perception au sein d’un panel, alors que les méthodes classiques se focalisent sur une vision moyenne de la perception du panel. De plus, à notre connaissance, ce travail est le premier à proposer l’identification d’un modèle de mélange de processus semi-markoviensTemporal Dominance of Sensations (TDS) is a technique to measure temporal perception of food product during tasting. For a panelist, it consists in choosing in a list of attributes which one is dominant at any time. This work aims to model TDS data with a stochastic process and proposes to use semi-Markov processes (SMP), a generalization of Markov chains which allows dominance durations to be modeled by any type of distribution. The model can then be used to compare TDS samples based on likelihood ratio. Because probabilities of transition from one attribute to another one can also depend on time, we propose to model TDS by period and we propose a method to select optimally the number of periods and the frontiers between periods. Graphs built upon the stochastic pattern can be plotted to represent main chronological transitions between attributes. Finally, this work introduces new statistical models based on finite mixtures of semi-Markov processes in order to derive consumer segmentation based on individual differences in temporal perception of a product.The methods are applied to various TDS datasets: chocolates, fresh cheeses and Gouda cheeses. Results show that SMP modeling gives new information about temporal perception compared to classical methods. It particularly emphasizes the existence of several perceptions for a same product in a panel, whereas classical methods only provide a mean panel overview. Furthermore, as far as we know, this work is the first one that considers mixtures of semi-Markov processes
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Costa, João Carlos Viana Cunha. "Inteligência geral e conhecimento específico no Futebol : Estudo comparativo entre inteligência geral e o conhecimento específico em jovens federados de diferentes níveis competitivos." Master's thesis, Universidade do Porto. Reitoria, 2001. http://hdl.handle.net/10216/9930.
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Dissertação de Mestrado em Ciência do Desporto, área de especialização em Desporto para Crianças e Jovens, apresentada à Faculdade de Ciências do Desporto e de Educação Física da Universidade do PortoA investigação actual vem realçando a importância dos processos cognitivos nas acções realizadas no âmbito dos Jogos Desportivos Colectivos, em virtude das características complexas da sua intervenção. Entre os requisitos considerados fundamentais, o conhecimento específico da modalidade parece possuir um peso importante na performance desportiva. Contudo, a existência dum elevado nível de conhecimento poderá não garantir uma elevada prestação, se os caminhos de circulação de informação não estiverem optimizados e se o jogador não for capaz de adaptar e reordenar a sua intervenção em cada momento de jogo.No âmbito da avaliação do conhecimento específico em Jogos Desportivos Colectivos, os protocolos têm privilegiado, simultaneamente, a análise da prontidão e da qualidade da resposta, através de inquéritos de resposta múltipla.No presente estudo pretende-se analisar e comparar a forma como a inteligência geral dos jogadores de Futebol e o seu conhecimento específico do jogo se relacionam. Mais especificamente, pretende-se: avaliar e comparar a Inteligência geral e o conhecimento específico do jogo em jovens praticantes de Futebol segundo os respectivos estatutos posicionais e nível competitivo; e contrastar a percepção do treinador, face à capacidade de decisão e ao conhecimento específico do jogo dos seus jogadores, com os resultados obtidos pelos seus jogadores nos testes de inteligência geral e do conhecimento específico do jogo.Para tal, foram utilizados o teste de atenção de Toulouse-Piéron, o teste das figuras Idênticas de Thurstone e as Matrizes Progressivas de Raven, para avaliar os processos cognitivos gerais dos jovens Futebolistas, bem como o protocolo de avaliação do conhecimento específico do jogo construído por Mangas (1999) e aperfeiçoado por Correia (2000). Estes instrumentos foram aplicados a uma amostra de 44 praticantes federados de futebol de diferentes níveis competitivos, com uma média de idades de 16.00±0.53 para o grupo de nível competitivo ...
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Costa, João Carlos Viana Cunha. "Inteligência geral e conhecimento específico no Futebol : Estudo comparativo entre inteligência geral e o conhecimento específico em jovens federados de diferentes níveis competitivos." Dissertação, Universidade do Porto. Reitoria, 2001. http://hdl.handle.net/10216/9930.
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Dissertação de Mestrado em Ciência do Desporto, área de especialização em Desporto para Crianças e Jovens, apresentada à Faculdade de Ciências do Desporto e de Educação Física da Universidade do PortoA investigação actual vem realçando a importância dos processos cognitivos nas acções realizadas no âmbito dos Jogos Desportivos Colectivos, em virtude das características complexas da sua intervenção. Entre os requisitos considerados fundamentais, o conhecimento específico da modalidade parece possuir um peso importante na performance desportiva. Contudo, a existência dum elevado nível de conhecimento poderá não garantir uma elevada prestação, se os caminhos de circulação de informação não estiverem optimizados e se o jogador não for capaz de adaptar e reordenar a sua intervenção em cada momento de jogo.No âmbito da avaliação do conhecimento específico em Jogos Desportivos Colectivos, os protocolos têm privilegiado, simultaneamente, a análise da prontidão e da qualidade da resposta, através de inquéritos de resposta múltipla.No presente estudo pretende-se analisar e comparar a forma como a inteligência geral dos jogadores de Futebol e o seu conhecimento específico do jogo se relacionam. Mais especificamente, pretende-se: avaliar e comparar a Inteligência geral e o conhecimento específico do jogo em jovens praticantes de Futebol segundo os respectivos estatutos posicionais e nível competitivo; e contrastar a percepção do treinador, face à capacidade de decisão e ao conhecimento específico do jogo dos seus jogadores, com os resultados obtidos pelos seus jogadores nos testes de inteligência geral e do conhecimento específico do jogo.Para tal, foram utilizados o teste de atenção de Toulouse-Piéron, o teste das figuras Idênticas de Thurstone e as Matrizes Progressivas de Raven, para avaliar os processos cognitivos gerais dos jovens Futebolistas, bem como o protocolo de avaliação do conhecimento específico do jogo construído por Mangas (1999) e aperfeiçoado por Correia (2000). Estes instrumentos foram aplicados a uma amostra de 44 praticantes federados de futebol de diferentes níveis competitivos, com uma média de idades de 16.00±0.53 para o grupo de nível competitivo ...
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Schaefer, Martina Christina Marion. "The interaction between speech perception and speech production: implications for speakers with dysarthria." Thesis, University of Canterbury. Communication Disorders, 2013. http://hdl.handle.net/10092/8610.
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The purpose of the research presented here was to systematically investigate the role of speech perception on speech production in speakers of different ages and those with PD and hypokinetic dysarthria. For this, the experimental designs of auditory perturbation and mimicry were chosen. The initial research phase established that the magnitude of
compensation to auditory vowel perturbation was reduced in 54 speakers of New Zealand English (NZE) when compared to previous studies conducted with speakers of American (AE) and Canadian English (CE). A number of factors were studied to determine possible predictors of compensation and distinguish between potential changes associated with ageing.
However, no predictors of compensation were found for the overall group. Post-hoc analyses established an increased variability in response patterns in NZE when compared to previous studies of AE and CE. Subsequent follow-up analyses focused on the response-dependent categories of (1) big compensators, (2) compensators, (3) big followers, and (4) followers. Linear mixed-effect modelling revealed that in big compensators, the magnitude of compensation was greater in speakers who exhibited larger F1 baseline standard deviation
and greater F1 vowel distances of HEAD relative to HEED and HAD. F1 baseline standard deviation was found to have a similar predictive value for the group of compensators. No
predictors of compensation were found for the other two subgroups. Phase two was set up as a continuation of phase one and examined whether a subset of 16 speakers classified as big compensators adapted to auditory vowel perturbation. Linear mixed-effect modelling revealed that in the absence of auditory feedback alterations, big compensators maintained
their revised speech motor commands for a short period of time until a process of de-adaptation was initiated. No predictors of adaptation were found for the group. Due to the
unexpected results from the first two research phases indicating a dominant weighting of somatosensory feedback in NZE compared to auditory-perceptual influences, a different experimental paradigm was selected for phase three - mimicry. The purpose of this study was to determine whether eight speakers with PD and dysarthria and eight age-matched healthy controls (HC) are able to effectively integrate speech perception and speech production when attempting to match an acoustic target. Results revealed that all speakers were able to modify their speech production to approximate the model speaker but the acoustic dimensions of their speech did not move significantly closer to the target over the three mimicry attempts. Although speakers with moderate levels of dysarthria exhibited greater acoustic distances (except for the dimension of pitch variation), neither the perceptual nor the acoustic analyses found significant differences in mimicry behaviour across the two groups. Overall, these findings were considered preliminary evidence that speech perception and speech production can at least to some extent be effectively integrated to induce error-correction mechanisms and subsequent speech motor learning in these speakers with PD and dysarthria.
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Feng, Shimin. "Sensor fusion with Gaussian processes." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5626/.
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This thesis presents a new approach to multi-rate sensor fusion for (1) user matching and (2) position stabilisation and lag reduction. The Microsoft Kinect sensor and the inertial sensors in a mobile device are fused with a Gaussian Process (GP) prior method. We present a Gaussian Process prior model-based framework for multisensor data fusion and explore the use of this model for fusing mobile inertial sensors and an external position sensing device. The Gaussian Process prior model provides a principled mechanism for incorporating the low-sampling-rate position measurements and the high-sampling-rate derivatives in multi-rate sensor fusion, which takes account of the uncertainty of each sensor type. We explore the complementary properties of the Kinect sensor and the built-in inertial sensors in a mobile device and apply the GP framework for sensor fusion in the mobile human-computer interaction area. The Gaussian Process prior model-based sensor fusion is presented as a principled probabilistic approach to dealing with position uncertainty and the lag of the system, which are critical for indoor augmented reality (AR) and other location-aware sensing applications. The sensor fusion helps increase the stability of the position and reduce the lag. This is of great benefit for improving the usability of a human-computer interaction system. We develop two applications using the novel and improved GP prior model. (1) User matching and identification. We apply the GP model to identify individual users, by matching the observed Kinect skeletons with the sensed inertial data from their mobile devices. (2) Position stabilisation and lag reduction in a spatially aware display application for user performance improvement. We conduct a user study. Experimental results show the improved accuracy of target selection, and reduced delay from the sensor fusion system, allowing the users to acquire the target more rapidly, and with fewer errors in comparison with the Kinect filtered system. They also reported improved performance in subjective questions. The two applications can be combined seamlessly in a proxemic interaction system as identification of people and their positions in a room-sized environment plays a key role in proxemic interactions.
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Johnston, Brian. "Electrochemical silver sensors for photographic processes." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4903/.
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A range of novel silver ionophores was synthesised based on the l,3-dithiole-2- thione-4,5-dithiolate (DMIT) building block. These were incorporated in ion-selective electrodes (ISEs) and applied to the determination of silver ion in photographic process solutions of interest to Kodak. Two classes of compounds were synthesised incorporating acyclic silver binding sites. The first class of compounds were 1,3 dithiole-2-ones functionalised with (i) a silver binding chain, and (ii) an alkyl chain, the latter allowing a range of compounds to be synthesised of varying lipophilicity. These compounds were applied as silver ionophores in plasticised PVC membranes and incorporated in ion-selective electrodes. The newly synthesised ionophores were compared to silver ionophores in the literature and to those previously used by Kodak. The membrane composition was optimised for silver ion selectivity over a range of metal cations of relevance to photographic process solutions. Samples of photographic emulsions were supplied by Kodak and subsequent analysis demonstrated successful detection of silver ion to micromolar levels with the ISE incorporating the newly synthesised ionophores. The second class of compounds was based on the tetrathiafulvalene (TTF) building block. A TTF derivative was synthesised incorporating two acyclic silver binding chains and a hydrophobic domain. The reversible redox properties of this compound enabled it to be applied as a transducer suitable for voltammetric analysis of silver ion. Titration of a solution of the new TTF compound with silver ion revealed that it was very sensitive; an equimolar quantity of silver ion resulting in a marked change in voltammetric behaviour. A silver ion binding constant was determined by ultraviolet spectrophotometry.
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Fuentes, Espinoza Alejandro. "Vin, réchauffement climatique et stratégies des entreprises : comment anticiper la réaction des consommateurs ?" Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0150/document.
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Il est communément admis que le réchauffement climatique aura des conséquencesimportantes sur de nombreux vignobles à travers le monde, avec des impacts sur la productionviticole, sur la qualité du raisin et donc sur la qualité des vins. A Bordeaux et dans d’autresrégions, le réchauffement est en partie la cause d’une modification de la composition chimiquedes raisins récoltés en conditions de maturité excessive. Les vins issus de leurs vinificationssont plus riches en alcool, moins acides et marqués par des caractéristiques aromatiquesrappelant des vins élaborés sous des latitudes plus chaudes et sèches.Dans ce contexte, le réchauffement climatique impliquera des enjeux économiques importantsdans la consommation du vin, et il peut être utile de connaître la capacité des consommateurs àaccepter durablement ces vins. L’objectif de cette thèse est à la fois prospectif par rapport auréchauffement climatique et de ses conséquences sur la qualité des vins et à la fois actuel parrapport à l’adéquation durable entre l’offre et la demande.La méthode d’analyse est celle d’un marché expérimental couplé à une analyse sensorielle. Lesexpériences avec des consommateurs ont montré les influences des caractéristiques des vins duréchauffement climatique sur les préférences des consommateurs et la valorisation des vins surle marché́. Enfin les résultats montrent que les consommateurs ont des valorisationsdifférenciées pour les procédés oenologiques ayant pour objectif de corriger les effets négatifsdu réchauffement climatiqueIt’s commonly accepted that global warming will have important consequences formany vineyards throughout the world, with impacts on wine production, on grape quality andtherefore on wines quality. In Bordeaux and other regions, warming is partly the cause of achange in the chemical composition of the grapes harvested under conditions of excessivematurity. The wines resulting from their vinification are richer in alcohol, less acidic andmarked by aromatic characteristics reminiscent wines produced in warmer and dryer latitudes.In this context, global warming will involve important economic stakes in wine consumption,and it may be useful to know the capacity of consumers to accept these wines durably. Theobjective of this thesis work is both forward-looking in relation to global warming and itsconsequences on wines quality and at the same time on the sustainable match between supplyand demand.The analysis methodology is an experimental market coupled with a sensory analysis.Experiences with consumers showed the influence of the characteristics of global warmingwines on consumer’s preferences and the wines valorisation on the market. Finally, the resultsshow that consumers have differentiated valorizations for oenological processes aimed atcorrecting the negative effects of global warming
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Pairin, Hongsoongnern. "Understanding the sensory characteristics of fresh and processed tomatoes using descriptive sensory analysis." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/261.
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Ryu, Jong Eun. "Nanomanufacturing processes for biofuel cells and sensors." Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1997615321&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Andry, Soucila. "Emergence de la parole chez des enfants paralysés cérébraux et pathologies associées." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAC044/document.
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Dans le cadre de cette recherche sur l'émergence de la parole auprès d'enfants paralysés cérébraux, ayant comme pathologie des troubles moteurs, nous avons situé notre démarche épistémologique dans le champ de théories qui permet de comprendre le développement cognitif général, avec le fonctionnement neurobiologique du cerveau et les processus moteurs biomécaniques et sensoriels,impliqués dans la production de parole. Dans notre étude, nous avons émis l'hypothèse de l'existence d'une corrélation entre le développement de la déglutition-mastication et l'émergence de la parole. Sous-jacents à cette corrélation, serait le développement du contrôle de la mandibule, ainsi que celui des articulateurs de la sphère oro-faciale (langue, lèvres, velum, épiglotte). Les résultats expérimentaux principaux montrent que malgré leurs pathologies, ces enfants suivent les tendances préférentielles observées chez les tous enfants « valides », avec la production d'un nouveau patron associatif qui apparaît, dont les sons labiaux et coronaux. En outre, notre étude indique que la saisie et la prise alimentaire, à travers sa diversité, ainsi que sa texture, permettraient l'évolution du développement pré-linguistique et linguistique chez ces enfants. Par ailleurs, nous pouvons souligner que les enfants présentant des troubles de l'oralité alimentaire, correspondant au trouble de l'oralité primaire, auront tendance à développer des troubles de l'oralité secondaire qui engendreront des troubles de la paroleIn this research on the emergence of speech among children with cerebral palsy, whose pathology is motor disorders, our epistemological approach lies within theories that help to understand general cognitive development, based on the neurobiological functioning of the brain, and also on motor biomechanical and sensory processes involved in speech production. ln our study, we hypothesized the existence of a correlation between the development of swallowing-mastication and the emergence of speech. Underlying this correlation would be the development of control of the mandible, as well as that of the articulators of the orofacial sphere (tongue, lips, velum and epiglottis). The main experimental results show that despite their pathologies, these children follow preferential trends observed in all "valid" children, with the production of a new associative pattern that appears, including labial and coronal sounds. ln addition, our study indicates that grasping and food intake, through ils diversity, as well as its texture, would favour the development of prelinguistic and linguistic maturity in these children. Moreover, we posit that children with eating disorders, corresponding to primary eating disorders, will tend to develop secondary eating disorders that will lead to speech disorders
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Alvarado, Pérez Miriam. "Development of Flexible Gas Sensors Based on Additive Fabrication Processes." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/669439.
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Els sensors de gasos s’utilitzen per a monitoritzar ambients interiors i exteriors. Algunes aplicacions comuns són per a mesurar el nivell de contaminants als carrers, els gasos alliberats per les fuites industrials i d’automòbils, els gasos a la mineria, el contingut d’alcohol en sang a través de l’alè exhalat, etc.
A mesura que creix el camp d’aplicació dels sensors de gasos, es fa necessari adaptar els sensors de gasos als nostres dispositius i pertinences diàries. Es requereixen materials mecànicament flexibles i resistents per a fabricar sensors de gasos flexibles. A banda de proves de detecció de gas, la resistència a la flexió dels sensors ha de provar-se per anomenar “flexible” a un sensor.
L’objectiu principal d’aquesta tesi és fabricar sensors de gasos flexibles mitjançant processos additius emprant òxids metàl·lics com a materials sensibles. Els sensors de gasos flexibles es varen fabricar utilitzant un substrat polimèric flexible (Kapton). Els diferents processos emprats varen ser compatibles amb la temperatura de funcionament del substrat. Entre les tècniques emprades estan la plantilla, la serigrafia, la injecció de tinta, AA-CVD. A més a més, es varen realitzar processos superficials per a millorar l’adhesió dels òxids metàl·lics al substrat polimèric. La flexibilitat dels sensors es va provar realitzant una prova de flexió cíclica.Los sensores de gas se utilizan para monitorear ambientes interiores y exteriores. Algunas aplicaciones comunes son para medir: el nivel de contaminantes en las calles, los gases liberados por los escapes industriales y de automóviles, los gases en la minería, el contenido de alcohol en la sangre a través del aliento exhalado, etc. A medida que crece el campo de aplicación de los sensores de gas, se hace necesario adaptar los sensores de gas a nuestros dispositivos y pertenencias diarias. Se requieren materiales mecánicamente flexibles y resistentes para fabricar los sensores de gas flexibles. Además de las pruebas de detección de gas, la resistencia a la flexión de los sensores debe probarse para llamar “flexible” a un sensor. El objetivo principal de esta tesis es fabricar sensores de gas flexibles a través de procesos aditivos utilizando óxidos metálicos como materiales sensibles. Los sensores de gas flexibles se fabricaron utilizando un sustrato polimérico flexible (Kapton). Los diferentes procesos empleados fueron compatibles con la temperatura de la temperatura de funcionamiento del sustrato. Entre las técnicas empleadas están la plantilla, la serigrafía, la inyección de tinta, AA-CVD. Además, se realizaron procesos superficiales para mejorar la adhesión de los óxidos metálicos al sustrato polimérico. La flexibilidad de los sensores se probó realizando una prueba de flexión cíclica.
Gas sensors are used to monitor indoor and outdoor environments. Some common applications are to measure: the level of pollutants in the streets, the gases liberated by industrial and car exhausts, gases in mining, blood alcohol content through the exhaled breath, etc. As the field of application for gas sensors is growing, it becomes necessary to adapt the gas sensors to our daily devices and belongings. This requires mechanically flexible and resistant materials to fabricate the flexible gas sensors. In addition to gas sensing tests, the resistance to bending of the sensors should be tested to call a sensor flexible. The main objective of this thesis is to fabricate flexible gas sensors through additive processes using metal oxides as sensitive materials. The flexible gas sensors were fabricated using a flexible polymeric substrate (Kapton). The different processes employed were compatible with the temperature of the operating temperature of the substrate. Among the techniques employed are stencil, screen-printing, inkjet-printing, AA-CVD. Also, surface processes were performed to improve the adhesion of the metal oxides to the polymeric substrate. The flexibility of the sensors was tested by performing a cyclical bending test.
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Foina, Aislan Gomide. "Monitoração de rede de sensores com transponders." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-08052007-163603/.
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Este trabalho apresenta os resultados obtidos no desenvolvimento de um sistema capaz de estabelecer um controle adequado do fluxo da informação e a supervisão de uma rede de sensores. O sistema se caracteriza pelo alto grau de flexibilidade possuindo uma camada de comunicação de dispositivos, uma camada de gerenciamento de regras de negócio para controlar o fluxo de processos, uma camada de interface homem - máquina e de interface com outros sistemas. A camada de comunicação com os dispositivos é responsável pela interface entre os mesmos e o núcleo do sistema, integrando, de forma transparente, diferentes equipamentos, tecnologias e fabricantes. A interface do usuário foi projetada em um único módulo para facilitar modificações sem comprometer o funcionamento geral do sistema. A interface com outros sistemas é feita por meio de drivers de comunicação, permitindo qualquer tipo de integração. O núcleo do sistema faz todo o controle de eventos, do fluxo do processo e geração alarmes, assim como recebimento e envio das informações da camada de dispositivos e da camada de interface. São descritas as diversas camadas da interface e sua implementação analisando as possíveis aplicações do sistema, juntamente com um estudo de caso do controle do processo de descarga de carga a granel no porto de Santos, usando tecnologia RFID. Os resultados obtidos nessa aplicação são descritos e comprovam a utilidade prática do sistema. Apresentam-se inicialmente alguns conceitos básicos necessários ao entendimento deste projeto como: sistemas distribuídos, estrutura webservice, linguagem XML e de tecnologias passíveis de integração com o sistema.This paperwork presents the results obtained with the development of a system capable of establishing a proper control of information flow and supervision of a sensors network. The system characterizes itself due to its great flexibility degree by having a devices communication layer, a business management layer to do the process flow control, a man-machine interface and interface with other systems layer. The devices communication layer is responsible for the interface between other devices and the system core, integrating in a transparent way, different equipment, technologies and manufactures. The user\'s interface was designed in a single module to facilitate modifications without compromising the system\'s general functioning. The interface with other systems is made throughout communication drivers, allowing any type of integration. The system core makes a control of all events, process flow and alarm generation, as well as receiving and sending information from the devices layer and interface layer. The several interface layers and its implementation are described analyzing the system\'s possible applications along with a case study of loading discharge in a bulk process control at Santos Port using RFID technology. The results obtained with this application are described and prove the practical utility of the system. Some necessary basic concepts to understand this project are presented initially as: distributed systems, web service structure, XML language and technologies subjected to integration with the system.
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Cechelero, Gustavo Sampaio e. Silva. "Sensores eletroquímicos para detecção de íons e medida de pH baseados em filmes de silício poroso." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-04072007-152612/.
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O presente trabalho foi realizado com o objetivo de contribuir para o desenvolvimento tecnológico de sensores eletroquímicos utilizados na detecção de íons, especificamente, de íons de hidrogênio (H+). Na primeira parte do trabalho é descrito e discutido o estado da arte de sensores eletroquímicos de H+, principalmente de dispositivos sensíveis a íons do tipo ISFET (Transistor de Efeito de Campo Sensível a Íons). O foco principal do presente trabalho foi na proposta de fabricação e caracterização funcional de um eletrodo modificado com moléculas de azul de metileno baseado na tecnologia de silício poroso. Os resultados obtidos neste trabalho mostraram que filmes de silício macroporoso modificados com azul de metileno atuam como eletrodos de trabalho com elevada taxa de transferência de elétrons, permitindo sua aplicação em dispositivos sensores eletroquímicos associado à técnica de voltametria cíclica. Os resultados observados nos voltamogramas deste eletrodo mostraram elevada sensibilidade a mudanças de pH da solução, parâmetro associado à concentração de íons de H+. A resposta do sensor foi monitorada pela intensidade de corrente de pico e posição do potencial de pico da reação redox das moléculas de azul de metileno do eletrodo macroporoso modificado. Os eletrodos modificados com azul de metileno em filmes de silício microporoso mostraram uma elevada resistência elétrica, impossibilitando sua aplicação como sensores utilizando-se a técnica de voltametria cíclica. No entanto, devido a sua elevada superfície especifica (600 m2/cm3), estes eletrodos foram aplicados na detecção de íons através da técnica de impedância eletroquímica. Os resultados obtidos com os eletrodos de silício poroso modificado com azul de metileno abrem grandes perspectivas de aplicação em biossensores e Chips de DNA.This work was done focused on contributing to the technologic development of electrochemical sensors employed in ions detection, specifically, hydrogen ions (H+). At the first part of the work, the H+ electrochemical sensors review is showed and discussed; mainly of the ion sensitive devices know as ISFET device (Ion Sensitive Field Effect Transistor). The work was focused in the purpose of fabrication and functional characterization of a modified electrode with methylene blue molecules based on porous silicon technology. The results obtained with this work showed that macroporous silicon films modified with methylene blue act as work electrodes with high electron transference rate, allowing their application in electrochemical sensor devices using cyclic voltammetry technique. The cyclic voltammetry experimental results of this electrode showed high sensibility to pH changes of the solution, parameter related to the H+ ion concentration. The sensor response was monitored by the intensity of peak current and peak potential position of the redox reaction of methylene blue molecules on modified porous silicon electrode. The modified electrodes with methylene blue on microporous silicon films showed a high electric resistance, making impossible their application as sensors employing the cyclic voltammetry technique. However, due to their high specific surface (600 m2/cm3), these electrodes were applied to ion detection through the electrochemical impedance technique. The results achieved with the porous silicon electrodes modified with methylene blue open great perspectives of application in biosensors and DNA Chips.
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Osborne, Michael A. "Bayesian Gaussian processes for sequential prediction, optimisation and quadrature." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:1418c926-6636-4d96-8bf6-5d94240f3d1f.
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We develop a family of Bayesian algorithms built around Gaussian processes for various problems posed by sensor networks. We firstly introduce an iterative Gaussian process for multi-sensor inference problems, and show how our algorithm is able to cope with data that may be noisy, missing, delayed and/or correlated. Our algorithm can also effectively manage data that features changepoints, such as sensor faults. Extensions to our algorithm allow us to tackle some of the decision problems faced in sensor networks, including observation scheduling. Along these lines, we also propose a general method of global optimisation, Gaussian process global optimisation (GPGO), and demonstrate how it may be used for sensor placement. Our algorithms operate within a complete Bayesian probabilistic framework. As such, we show how the hyperparameters of our system can be marginalised by use of Bayesian quadrature, a principled method of approximate integration. Similar techniques also allow us to produce full posterior distributions for any hyperparameters of interest, such as the location of changepoints. We frame the selection of the positions of the hyperparameter samples required by Bayesian quadrature as a decision problem, with the aim of minimising the uncertainty we possess about the values of the integrals we are approximating. Taking this approach, we have developed sampling for Bayesian quadrature (SBQ), a principled competitor to Monte Carlo methods. We conclude by testing our proposals on real weather sensor networks. We further benchmark GPGO on a wide range of canonical test problems, over which it achieves a significant improvement on its competitors. Finally, the efficacy of SBQ is demonstrated in the context of both prediction and optimisation.
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Antoniou, Michalis. "Localisation of wireless sensor nodes in confined industrial processes." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/localisation-of-wireless-sensor-nodes-in-confined-industrial-processes(74bd1acf-5e09-4daf-91ee-a82cb0263a6d).html.
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Work described in this thesis is concerned with localisation techniques, for determining the position, of wireless sensors whilst these are immersed in confined industrial processes, such as those occurring in the chemical, pharmaceutical and food processing industries. Two different approaches to localisation were investigated. The first approach employed an existing hardware system that used ultra wide band (UWB) signals whist the second approach used a network localisation method based on information from narrow-band received signals. A prototype UWB-based localisation algorithm processed experimental received UWB pulses to detect their leading edges (LE) that were used to derive Time Difference of Arrival (TDoA) data. In turn TDoA data were converted into distances and used to compute the locations of the sensor nodes. Nevertheless, the process of detecting the LEs caused significant errors in the localisation process. To deal with this problem new automated adaptive LE detection methods were derived that succeeded in reducing localisation errors by half, compared to the prototype method, reaching accuracies of ±2cm. Thorough analysis of TDoA profiles revealed that these follow specific trends depending on the positions of the sensor nodes. A number of properties of TDoA profiles are proved mathematically and incorporated into seven localisation algorithms. These algorithms were examined using experimental TDoA data and shown to achieve average localisation errors up to 3cm. Network-based localisation was examined at a later stage of this research since complexities of large scale measurements and difficulties with equipment, delayed acquiring experimental data. The deployed network consisted of a number of nodes whose positions were known (anchors) that were used to estimate the positions of sensor nodes whose positions where considered to be unknown. Localisation was based on received signal strength (RSS) data, at every node to be localised, in anticipation that RSS could provide distance information that could be used in the localisation procedure. Nevertheless, fluctuations in RSS only allowed using localisation algorithms that associated RSS to the positions of anchors. The average localisation error in the network-based localisation algorithms was between 30cm to 100cm.
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Vatani, Morteza. "Additive Manufacturing of Stretchable Tactile Sensors: Processes, Materials, and Applications." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1436202948.
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Dementyev, Alexander. "Verbesserung der Performance von virtuellen Sensoren in totzeitbehafteten Prozessen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-156573.
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Modellbasierte virtuelle Sensoren (VS) ermöglichen die Messung von qualitätsbestimmenden Prozessparametern (bzw. Hilfsregelgrößen) dort, wo eine direkte Messung zu teuer oder gar nicht möglich ist. Für die adaptiven VS, die ihr internes Prozessmodell nach Data-Driven-Methode bilden (z. B. durch die Benutzung künstlicher neuronaler Netze (KNN)), besteht das Problem der Abschätzung der Prädiktionsstabilität. Aktuelle Lösungsansätze lösen dieses Problem nur für wenige KNN-Typen und erfordern enormen Entwurfs- und Rechenaufwand. In dieser Arbeit wird eine alternative Methode vorgestellt, welche für eine breite Klasse von KNN gilt und keinen hohen Entwurfs- und Rechenaufwand erfordert. Die neue Methode wurde anhand realer Anwendungsbeispiele getestet und hat sehr gute Ergebnisse geliefert. Für die nicht adaptiven virtuellen Sensoren wurde eine aufwandsreduzierte Adaption nach Smith-Schema vorgeschlagen. Dieses Verfahren ermöglicht die Regelung totzeitbehafteter und zeitvarianter Prozesse mit VS in einem geschlossenen Regelkreis. Im Vergleich zu anderen Regelungsstrategien konnte damit vergleichbare Regelungsqualität bei einem deutlich geringeren Entwurfsaufwand erzielt werdenModel-based virtual sensors allow the measurement of parameters critical for process quality where a direct measurement is too expensive or not at all possible. For the adaptive virtual sensors built after data-driven method (e.g., by use of an ANN model) there is a problem of the prediction stability. Current solutions attempt to solve this problem only for a few ANN types and require a very high development effort. In this dissertation a new method for the solution of this problem is suggested, which is valid for a wide class of the ANNs and requires no high development effort. The new method was tested on real application examples and has delivered very good results. For the non-adaptive virtual sensors a simple adaptation mechanism was suggested. This technique allows the control of dead-time and time-variant processes in closed loop. Besides, in comparison to other control strategies the comparable results were achieved with smaller development effort
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Carvalho, Daniel Orquiza de. "Desenvolvimento de processos de fabricação de dispositivos óptico integrados em tecnologia de silício para aplicação em sensoriamento." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-19092012-170421/.
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Os objetivos desta tese são: o estudo e aprimoramento dos diferentes parâmetros geométricos e de processo de fabricação de guias de onda ARROW (Anti-Resonant Reflecting Optical Waveguides), visando reduzir as perdas por propagação; e o projeto, fabricação e caracterização de sensores óptico integrados utilizando os processos aprimorados. Os parâmetros estudados foram: os materiais utilizados nas camadas antirresonantes, as espessuras destas camadas, a profundidade de corrosão para definição do rib e a rugosidade nas paredes laterais, que considera-se o parâmetro mais crítico no que diz respeito às perdas por propagação obtidas com o processo de fabricação utilizado neste trabalho. Os materiais utilizados na fabricação dos guias de onda ARROW sobre substrato de silício foram filmes de oxinitreto de silício (SiOxNy) depositados por PECVD à temperatura de 320°C, filmes de SiO2 crescidos em forno de oxidação em ambiente úmido a 1200°C e filmes de TiOxNy depositados pela técnica de Magnetron Sputtering Reativo. A definição das paredes laterais dessas estruturas foi feita através da Corrosão por Plasma Reativo (RIE) e técnicas fotolitográficas convencionais. Para o aprimoramento dos processos, as técnicas de caracterização utilizadas foram: medidas de perdas por propagação, utilizando a técnica de vista superior e a análise modal dos guias de onda. A principal contribuição deste trabalho foi a proposição de um processo de fabricação alternativo, onde pedestais são utilizados para a definição das paredes laterais antes da deposição do núcleo dos guias de onda. Este processo permitiu a redução significativa das perdas e o corte dos modos superiores para guias com larguras menores ou iguais a 6 µm. Finalmente, com os guias e os processos aperfeiçoados foram fabricados dois diferentes tipos de sensores ópticos: sensores refratométricos baseados em interferômetro de Mach-Zehnder (IMZ) e sensores de umidade baseados em absorção utilizando o polímero polipirrol (PPy). A caracterização dos sensores baseados em IMZ permitiu concluir que, embora se tenha observado uma resposta do sensor em termos de variação da potência na saída do dispositivo com a variação do índice de refração, esta variação possivelmente está sendo influenciada pela interferência multimodo resultante de limitações do processo de fabricação, o que reduz significativamente a sensibilidade com relação a valores projetados. Os sensores de umidade apresentaram uma variação significativa da potência de saída para umidades relativas ao redor de 70%, permitindo sua utilização em diferentes aplicações, como na indústria alimentícia e no monitoramento da qualidade do ar.The main goals of this thesis are: the study and improvement of different geometrical and fabrication process parameters of Anti-Resonant Reflecting Optical Waveguides (ARROWs), aiming at reducing the propagation losses; and the design, fabrication and characterization of integrated optics sensors using the improved processes. The studied parameters were: the materials used as anti-resonant layers, the thickness of these layers, the rib height and the sidewall roughness (SWR), which is considered the most critical parameter with respect to propagation losses in the fabrication process used in this work. The materials used in the fabrication of ARROW waveguides over silicon substrate were silicon oxynitride (SiOxNy) films deposited by PECVD at 320°C, SiO2 films, thermally grown at 1200°C and TiOxNy films deposited by the reactive magnetron sputtering technique. The definition of the sidewalls of these waveguides was performed by Reactive Ion Etching (RIE) and conventional photolithographic techniques. The characterization techniques used were: propagation loss measurements, using the top view technique and modal analysis. The main contribution of this work was the proposition of an alternative fabrication process where pedestals are used in order to define the sidewalls before deposition of the core of the ARROW waveguides. This process allowed significant reduction of losses and cutoff of higher modes at widths of 6 µm. Finally, with the waveguides and improved processes two different types of optical sensors were fabricated: refractometric sensors based on Mach-Zehnder interferometer (IMZ) and humidity sensors based on evanescent field absorption using polypyrrole polymer (PPy). The characterization results of IMZ based sensors showed that, although a sensor response has been observed in terms of change of output power with variation of the external medium\'s refractive index, this variation is possibly being influenced by multimode interference resulting from limitations in the fabrication process. This significantly reduces the sensitivity with respect to designed values. The humidity sensors show a significant variation in output power for relative humidity values around 70%, allowing its use in different applications, such as in food industry and in air quality monitoring.
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Aiyar, Avishek R. "Microfabrication of a MEMS piezoresistive flow sensor - materials and processes." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24696.
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Schühli, Luciano Alcindo. "Monitoramento de operações de retificação usando fusão de sensores." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18140/tde-07042008-130554/.
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O presente trabalho trata da análise experimental de um sistema de monitoramento baseado na técnica de fusão de sensores, aplicado em uma retificadora cilíndrica externa. A fusão é realizada entre os sinais de potência e emissão acústica para obtenção do parâmetro FAP (Fast Abrasive Power) através do método desenvolvido por Valente (2003). Através da simulação de problemas encontrados nos processos de retificação (falha de sobremetal, colisão, desbalanceamento e vibração), foram captados os sinais de potência e emissão acústica e a partir destes gerado o parâmetro FAP, comparando seu desempenho, na detecção dos problemas, com os outros dois sinais. Para a análise foram construídos os gráficos das variações dos sinais em relação ao tempo de execução do processo e os mapas do FAP e acústico. O sistema de monitoramento avaliado tem como característica baixa complexidade de instalação e execução. Os dados experimentais revelam que o FAP apresenta uma velocidade de resposta maior que a potência e levemente amortecida em relação à emissão acústica. O nível do seu sinal é igual ao da potência mantendo-se homogêneo durante o processo, ao contrário da emissão acústica que pode ser influenciada por diversos outros parâmetros, tais como geometria da peça, distância do sensor, montagem do sensor, entre outros, que independem da interação ferramenta-peça. O resultado é uma resposta dinâmica e confiável, associada à energia do sistema. Estas características são interessantes para o monitoramento de processos de retificação (excluindo a dressagem) sendo superiores àquelas apresentadas isoladamente pelos sinais de potência e emissão acústica.The present study deals with an experimental analysis of a monitoring system based on a sensor fusion strategy applied to a cylindrical grinding machine. It comprises a fusion of the power and acoustic emission signals and has as main goal to obtain the FAP (Fast Abrasive Power) using the method developed by Valente (2003). Initially, the power and acoustic emission signals were captured under operational dysfunction conditions during the grinding process (stock imperfection, collision, unbalancing e vibration). Then, based on these signals, the FAP parameter was generated and its capability in characterizing operational dysfunctions evaluated against the performance of an individual analysis of the power and acoustic emission signals. For this analysis, FAP and acoustic maps plus plots showing the FAP signals vs. working time were implemented. The experimental data revealed that the FAP presents a faster response than the power signal and a slightly dumped response when compared against the acoustic signal. The signal level of the FAP is similar to the power signal and is homogenous during the machining process. On contrary to the FAP, the acoustic emission signal may be affected by parameters that are not related to the tool-workpiece interactions, workpiece geometry and sensor positioning. The dynamic response of FAP is reliable and linked to the energy of the system. Finally, it should be highlightened that the monitoring system based on the FAP parameter presents low complexity in both implementation and execution. Such characteristics are superior to those observed when using either the power or acoustic emission signals and highly valuable in a system designed to monitor grinding processes.
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Han, Liqing. "Physical and sensory properties of oat cakes /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418026.
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Pereira, Rodrigo Solano. "Estudo de sensores baseados em luminescência eletroquímica (ECL) sem marcadores." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-22032017-095002/.
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Esta pesquisa apresenta o desenvolvimento de um sensor para fenotiazina baseados em luminescência eletroquímica (ECL) com Ru(bpy)3 como elemento ativo. Para desenvolver este sensor, foram utilizados três materiais como eletrodo de trabalho, sendo estes materiais carbono vitreo, ouro e oxido de índio-estanho (ITO). O eletrodo de trabalho é modificado com a deposição de um filme fino de TiO2/nafion. O desempenho de cada material é comparado com os demais e com dados já apresentados na literatura. A novidade apresentada por esta pesquisa é a utilização de ouro e ITO como eletrodos de trabalho para o sistema de ECL Ru(bpy)/fenotiazina. Também, esta pesquisa apresenta um estudo sobre a influência da espessura do filme sobre a intensidade do sinal de ECL. Os estudos apresentados nesta dissertação se referem à otimização do filme de TiO2/nafion e do eletrodo de trabalho utilizado, visando produzir o sensor mais sensível à presença de fenotiazina em uma solução fisiológica. Sensores que utilizam o fenômeno da ECL para detecção de analitos são utilizados com frequência por apresentarem grande sensibilidade e seletividade. Sua principal aplicação se encontra em sistemas onde o analito é uma macromolécula, uma amina, caso comum para soluções fisiológicas. Fenotiazina é uma substância interessante como alvo porque seus derivados são largamente utilizados em drogas para o tratamento de doenças psiquiátricas, como depressão e esquizofrenia. Então, se faz necessário monitorar de maneira segura a ingestão e absorção desses medicamentos pelos pacientes.This research presents the development of a electrochemioluminescence (ECL) based sensor aimed to detect phenothiazine in physiologic solutions. To develop this sensor, three materials were used, being glass carbon, gold and indium-tin oxide (ITO) for the working electrode of the sensor. The working electrode was modified by the deposition of a composite thin film of TiO2/nafion in its surface. Each material then was compared in terms of the ECL signal intensity between themselves and data from previous researches. The novelty presented in this work is the use of gold and ITO as base materials for the working electrode of the sensor. Also, as a novelty, this research presents a study of the influence of the film thickness over the ECL signal intensity. This thesis presents studies concerning the optimization of the TiO2/nafion film and the influence of the working electrode material, aiming to produce the best possible sensor for phenothiazine in physiological solutions. ECL based sensor are often used today due to their great selectivity and sensibility. They are mainly used for detecting macromolecules, such as DNA and proteins in physiologic solutions. Phenothiazine is an interesting substance because its derivatives are commonly used on pharmaceutical drugs used to treat phycological diseases, such as depression and schizophrenia.
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Williams, Mark. "Dynamique de l’excitabilité corticale dans l’épilepsie-absence et intégration sensorielle Integrative properties and transfer function of cortical neurons initiating absence seizures in a rat genetic model Building Up Absence Seizures in the Somatosensory Cortex: From Network to Cellular Epileptogenic Processes." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS608.
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Une crise d’épilepsie résulte de la survenue soudaine d’une activité neuronale anormalement intense, rythmique et synchrone dans une région plus ou moins étendue du système nerveux central. Les conséquences cliniques sont extrêmement variées, selon les zones cérébrales affectées et la durée des crises, allant de brèves secousses musculaires très focalisées à une perte de conscience complète, éventuellement associée à des convulsions. Dans le cas de l’épilepsie-absence, une épilepsie généralisée d’origine génétique survenant fréquemment chez les enfants, les crises s’expriment essentiellement par une suspension des processus conscients dans toutes leurs dimensions, y compris une interruption des perceptions conscientes. Ces symptômes sont corrélés à des décharges de pointes-ondes (DPO) dans les électroencéphalogrammes (EEG) bilatéraux. Les mécanismes physiopathologiques des altérations de conscience au cours des crises d’épilepsie-absence restent l’objet de débats intenses, opposant des altérations fonctionnelles à grande échelle à un filtrage des informations exogènes par les oscillations épileptiques. Au cours de mes recherches, j’ai exploré l’hypothèse alternative, mais non exclusive, d’un dysfonctionnement dynamique dans les processus d’intégration sensorielle au sein des circuits thalamo-corticaux primaires. Des explorations électrophysiologiques fines n’étant pas réalisables chez les enfants épileptiques, j’ai utilisé un modèle génétique présentant une forte homologie avec la pathologie humaine : le Genetic Absence Epilepsy Rat from Strasbourg (GAERS). En combinant in vivo des enregistrements électrocorticographiques (ECoG) et intracellulaires dans le cortex somatosensoriel primaire (S1), précédemment identifié comme le site de déclenchement des crises, j’ai d’abord analysé les propriétés intégratives et d’excitabilité des neurones pyramidaux du cortex S1, durant et en dehors des crises, et je les ai comparées à celles des neurones homologues chez des rats non épileptiques. J’ai montré que ces neurones présentent lors des périodes inter-ictales une excitabilité accrue, s‘exprimant par une augmentation de la décharge des neurones en réponse à des stimulations excitatrices d’intensité croissante ainsi qu’une tendance exacerbée à se re-polariser suite à une hyperpolarisation de grande amplitude, suggérant un accroissement du courant cationique h. Au cours des crises, les mêmes neurones montraient des changements différentiels dans leur excitabilité membranaire selon la composante pointe ou onde dans l‘ECoG correspondant. La pointe était associée à une augmentation de décharge évoquée par un courant dépolarisant et à une diminution de résistance membranaire. Symétriquement, l’onde était corrélée avec une augmentation de résistance membranaire et une diminution d’excitabilité. Ces changements dynamiques des propriétés intégratives neuronales suggèrent une instabilité des réponses corticales lors du cycle pointe-onde pouvant « brouiller » les signaux sensoriels lors des crises. J’ai testé cette hypothèse en analysant les réponses des neurones corticaux, et des neurones thalamo-corticaux correspondants, à des stimulations appliquées sur les vibrisses controlatérales. Bien que les réponses synaptiques induites dans les neurones du cortex S1 par les stimulations sensorielles n’étaient pas globalement altérées lors des crises, elles étaient plus amples et plus efficaces pour déclencher des potentiels d’action pendant l’onde comparé à la composante pointe. Cet accroissement relatif de la réponse neuronale lors de l’onde ECoG résulte probablement de l’accroissement de résistance membranaire précédemment décrit, d’une augmentation de la force électromotrice des courants synaptiques glutamatergiques et de la forte probabilité de décharge des neurones thalamiques correspondants lors de cette composanteAn epileptic seizure results from the sudden occurrence of abnormally intense, rhythmic and synchronous neuronal activity, in a more or less broad region of the central nervous system. The clinical consequences are extremely varied, depending on the affected brain areas and the duration of the seizures, ranging from brief localized muscular twitches to a complete loss of consciousness, potentially associated with convulsions. Absence epilepsy is a generalised epilepsy of genetic origin, mostly affecting children of school age. During absence attacks, children experience a suspension of conscious processes in all their dimensions, including an interruption of conscious perceptions. These symptoms are correlated with bilateral spike-wave discharges (SWD) in the electroencephalograms (EEGs). The pathophysiological mechanisms underlying the alteration of consciousness during absences remain the subject of an intense debate, opposing functional dysfunctions on large scale neural networks to a filtering of sensory information by epileptic oscillations. During my PhD research, I explored the alternative, but not exclusive, hypothesis of a dynamic dysfunction in sensory integration processes within primary thalamo-cortical circuits. Given that multi-scale electrophysiological investigations cannot be conducted in epileptic children, I used a genetic model prsenting a strong homology with the human pathology: the Genetic Absence Epilepsy Rat from Strasbourg (GAERS).By combining in vivo electrocorticographic (ECoG) and intracellular recordings in the primary somatosensory cortex (S1), previously identified as the site of seizure initiation, I first analysed the integrative properties and excitability of S1 pyramidal neurons, during and in between seizures, and compared them to those measured in homologous neurons from non-epileptic rats. I showed that these neurons exhibit a higher excitability during inter-ictal periods, expressed as an increased firing response to excitatory stimuli of increasing intensity, as well as an exacerbated tendency to depolarize following a hyperpolarization of large amplitude, suggesting an augmented cationic current h. During seizures, the same neurons showed specific changes in their membrane excitability, according to the spike or wave component in the corresponding ECoG. The spike component was associated with increased current-evoked firing and a decreased membrane resistance. Conversely, the wave was correlated with an increase in membrane resistance and a decrease in excitability. These dynamic changes in neuronal integrative properties suggest an instability of cortical responses during the spike-wave epileptic cycle that could "scramble" sensory signals during seizures. I tested this hypothesis by analysing the sensory responses of cortical neurons, and corresponding thalamo-cortical neurons, to stimulations applied to contralateral whiskers. Although synaptic responses induced in S1 neurons by sensory stimuli were not globally impaired during seizures, they were larger and more likely to trigger action potentials during wave compared to the spike component. This relative increase in neuronal responsiveness during the ECoG wave probably results from the previously described increase in membrane resistance, an augmented driving force of glutamatergic synaptic currents and a higher probability of action potentials discharge in the corresponding thalamic neurons during this component. My doctoral research indicates that sensory inputs processing persists in the thalamo-cortical circuits during SWDs, but that the alternation of the spike and wave components introduces a strong instability of the neuronal responses during seizures. This new pathophysiological mechanism could contribute to the inability to generate a conscious, stable and effective, perception during generalised epileptic seizures
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Iwaki, Takuya. "Wireless Sensor Network Scheduling and Event-based Control for Industrial Processes." Licentiate thesis, KTH, Reglerteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-237527.
Full textAbstract:
Control over wireless sensor and actuator networks is of growing interest in process industry since it enables flexible design, deployment, operation, and maintenance. An important problem in industrial wireless control is how to limit the amount of information that needs to be exchanged over the network. In this thesis, network scheduling and remote control co-design is considered to address this problem. In the first part, we propose a design of an optimal network schedule for state estimation over a multi-hop wireless sensor network. We formulate an optimization problem, minimizing a linear combination of the averaged estimation error and transmission energy. A periodic network schedule is obtained, which specifies when and through which routes each sensor in the network should transmit its measurement, so that an optimal remote estimate under sensor energy consideration is achieved. We also propose some suboptimal schedules to reduce the computational load. The effectiveness of the suboptimal schedules is evaluated in numerical examples. In the second part, we propose a co-design framework for sensor scheduling, routing, and control over a multi-hop wireless sensor and actuator network. For a decoupled plant and LQG control performance, we formulate an optimization problem and show that the optimal schedule, routing, and control can be obtained locally for each control loop. In this part, we also introduce algorithms to reconfigure the schedules and routes when a link in the network is disconnected. The results are illustrated in a numerical example. In the third part, we consider event-based feedforward control from a wireless disturbance sensor. We derive stability conditions when the closed-loop system is subject to actuator saturation. Feedforward control with anti-windup compensation is introduced to reduce the effect of actuator saturation. The effectiveness of the approach is illustrated in some numerical examples.QC 20181029
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Cann, Maria. "Laser ablation processes of silver nanowire transparent conductors for capacitive touch sensors." Thesis, University of Surrey, 2016. http://epubs.surrey.ac.uk/811003/.
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Silver nanowire (AgNW) films have been shown to have transparent and conductive properties suitable to replace indium tin oxide (ITO) in applications such as touch sensors. However few studies have been conducted to investigate how these films may be processed to produce functional devices on a manufacturing scale. In this study, methods of optimising the transparent conductive properties of AgNW films made from commercially available nanowire sources, while minimising processing costs are considered. Rinsing and heating films post deposition yield films of a higher transmission at a set sheet resistance of 100 ohms per square (Ω/□), and reduce the required volume of nanowires by up to 45%, reducing material costs. These films are then processed by laser ablation to demonstrate successful electrical isolation can be achieved in geometries with dimensions as low as 45 μm, at laser fluences less than 25% of that required for processing ITO. However, confining the dimensions of the AgNW tracks can increase sheet resistance locally, compared to that of the unprocessed films, at dimensions commonly used in touch sensors. Despite this, working single sided five inch sensors are fabricated by laser ablation, with sensitivity, charge time and scribe visibility comparable to that of the same design of sensor on ITO. The lifetime of these nanowire devices is then considered, looking in to the effects of high voltage electrical discharge through the device, migration of material when in operation at high temperature and humidity and degradation due to exposure to air. Overcoats are employed to limit damage, with four candidates showing benefits. However, failure of sensors due to electrostatic discharge testing could not be prevented.
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Liebfried, Oliver. "The Investigation of Electromagnetic Processes in Electromagnetic Launchers Using Colossal Magnetoresistance Sensors." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110615_180000-02329.
Full textAbstract:
The development of rails and armatures which ensure a sliding solid-to-solid contact during the whole projectile acceleration is a great challenge in the field of railgun technology. Multifaceted physics exists at the sliding contact interface: The current concentrates at the rear of the interface due to magnetic diffusion processes and the fast armature movement. Consequently, Joule heating leads to enhanced wear in this region. In this dissertation, magnetic diffusion in railguns is investigated by means of measuring magnetic fields with CMR-B-scalar sensors at static and dynamic experimental conditions. These novel sensors, based on La0.83Sr0.17MnO3 thin films exhibiting colossal magnetoresistance were adapted for the use at railguns. It was found that these sensors are effective tools to measure the magnitude of high pulsed magnetic fields independent of the field orientation. Magnetic field distributions influenced by proximity and velocity skin effect could be measured in the harsh railgun environment. The obtained results allowed to estimate the skin depth in the rails at the sliding interface of a fast moving armature (>1500m/s). Furthermore experiments with fixed multiple brush armatures showed that front brushes can have contact problems in case of missing contact pressure.Pagrindiniai bėgių tipo elektromagnetinių svaidyklių technologijos uždaviniai yra susiję su daugybe fizikinių reikinių, vykstančių sviedinio kontaktų sąlyčio su bėgiais riboje. Todėl elektromagnetinių procesų, atsirandančių dėl didelių elektros srovės tankių ir slydimo greičių tyrimas yra svarbus šios srities uždavinys. Dėl magnetinės difuzijos ir greito sviedinio judėjimo, srovė koncentruojasi galinėje kontakto dalyje, kuri dėl stipraus Joule šilimo greitai susidėvi, o tai apriboja svaidyklės efektyvumą. Disertacijoje pateikiami magnetinio lauko difuzijos tyrimai bėgių tipo svaidyklėse panaudojant specialius jutiklius magnetinių laukų matavimui. Šie nauji jutikliai, pagaminti iš plonų La0,83Sr0,17MnO3 sluoksnių, pasižyminčių milžiniškos magnetovaržos (MM) reiškiniu (MM-B-skaliariniai jutikliai), buvo pritaikyti svaidyklėse, veikiančiose statiniame ir dinaminiame režime, esant dideliems elektromagnetinių triukšmų lygiams ir mechaniniams įtempiams. Darbo metu buvo nustatyta, jog šiais jutikliais galima išmatuoti stipraus magnetinio lauko impulso amplitudę, kai nėra žinoma šių laukų kryptis. Buvo ištirti nevienalyčių magnetinių laukų pasiskirstymai bėgiuose, atsirandantys dėl artumo efekto bei greičio skinefekto, sviediniui judant greičiau nei 1500m/s. Bandymai su įtvirtintu daugelio šepetėlių konstrukcijos sviediniu parodė, kad priekiniai šepetėliai, dėl nepakankamo Lorenco jėgos sukuriamo slėgio, gali pararasti elektrinį kontaktą su bėgiais.