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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Microwave thermography for the detection of breast cancer a discussion and evaluation of a 6 GHz system

Rosen, Bruce Robert January 1980 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Physics, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaves 190-193. / by Bruce Robert Rosen. / M.S.
32

Mesure d'émissivité pour la thermographie infrarouge appliquée au diagnostic quantitatif des structures / Emissivity measurement for Infrared thermography applied to quantitative diagnostic of structure

Monchau, Jean-Pierre 28 November 2013 (has links)
La thermographie infrarouge constitue un outil de diagnostic très utile dans le domaine du bâtiment et du génie civil. Cependant un diagnostic quantitatif reste difficile, et l'émissivité des surfaces étudiées joue un rôle important. Le présent travail est une étude sur la mesure d'émissivité pour le diagnostic quantitatif des structures par thermographie. Un des enjeux est de compléter une base de données d'émissivité pour des matériaux du bâtiment et du génie civil ; pour cela il a été nécessaire de développer des appareils de mesure portables. Deux appareils ont été développés au CERTES, utilisant des méthodes indirectes. Ces méthodes consistent à mesurer la réflexion d'un flux infrarouge modulé et nécessite une référence de réflectance connue. Le premier appareil module le flux par modulation lente de température (mesure en 16mn) ; il est adapté aux surfaces diffusantes et hétérogènes comme les bétons bitumineux et les matériaux de construction du bâtiment. L'autre appareil utilise un système d'écran permettant une modulation plus rapide (mesure en quelques secondes). Il est plus polyvalent. Il est aussi plus facilement transportable et permet également d'obtenir une évaluation du caractère plus ou moins spéculaire de la surface. Ces deux appareils couvrent au choix une bande spectrale large (1 à 40µm) pour évaluer les propriétés radiatives des surfaces et une bande étroite (8 à 14µm) adaptée à la sensibilité des caméras infrarouges. Une étude comparative sur les mesures d'émissivité a été entreprise avec le LNE (Laboratoire National de Métrologie et d'Essais). Les échantillons utilisés pour cette étude comparative ont permis de tester les différents dispositifs pour des matériaux ayant des propriétés radiatives très variées. Des mesures ont été effectuées au laboratoire et sur site sur une large gamme de matériaux usuels du bâtiment et du génie civil / Thermography is a very useful diagnosis tool in buildings and civil engineering structures. However quantitative diagnosis remains difficult, and having accurate values of surface emissivity is an important factor. The present work is a study about emissivity measurement for quantitative diagnosis with thermography. We needed accurate measurement of the emissivity of a number of civil engineering materials, in order to create a database. Thus, it was necessary to develop new portable measurement devices. Two devices using an indirect measurement method were developed at CERTES laboratory. The method uses the measurement of the reflectivity from a modulated IR source and requires calibration with a highly reflective surface. The first device uses a low-frequency, thermal modulation well-adapted to laboratory measurements, whereas the second one is a portable system using a mechanical modulation at a faster frequency, more appropriate to outdoor measurements. Both devices allow measurements in the broad (1—50µm) and narrow (8—14µm) bands. Experiments were performed on a large number of materials commonly used in buildings and civil engineering structures. The final objective of this work is to build a database of emissivity for these materials. A comparison of laboratory and on-site measurements of emissivity values obtained in both spectral bands is presented along with an estimation and an analysis of measurement uncertainties. A comparative study with measurement obtained at LNE (Laboratoire National de Métrologie et d'Essais, French laboratory of metrology) was performed, using a range of materials with widely different radiative properties. An analysis of discrepancies and their possible causes is presented
33

Investigation of the radiometric integrity of the therogram after its raster scan lines are removed through spatial filtration /

Allamena, Joan A. January 1983 (has links)
Thesis (B.S.)--Rochester Institute of Technology, 1983. / Typescript. Includes bibliographical references (leaf 24).
34

Termografia e ultrassonografia Doppler do plexo pampiniforme e termografia do escroto de touros: correlação com a qualidade do sêmen

Portugal, Elói dos Santos [UNESP] 07 February 2014 (has links) (PDF)
Made available in DSpace on 2015-04-09T12:28:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-07Bitstream added on 2015-04-09T12:48:10Z : No. of bitstreams: 1 000814318.pdf: 799152 bytes, checksum: 36f7b91352463121d3390598b87e5119 (MD5) / O Brasil possui o maior rebanho bovino comercial do mundo e chegou a 212,8 milhões de cabeças em 2011. Foram comercializadas 12,3 milhões de doses de sêmen bovino em 2012. O efetivo de fêmeas bovinas em idade reprodutiva é 61,4 milhões e a utilização de duas doses de sêmen por vaca estima-se que 10% do rebanho nacional está sendo inseminado. A fertilidade é uma importante característica nos sistemas produtivos e o macho de grande importância. Utilizando a termografia infravermelha (TIV) e ultrassonografia Doppler a termorregulação e o fluxo sanguíneo foram avaliados em touros. Dois grupos de seis touros foram avaliados por um ano e os dados obtidos da termografia – temperatura global do plexo (TGP), temperatura global do escroto (TGE), temperatura do plexo esquerdo (TPE), temperatura do plexo direito (TPD), temperatura do escroto esquerdo (TEE), temperatura do escroto direito (TED) e da ultrassonografia Doppler – velocidade sistólica máxima (VSM), velocidade diastólica final (VDF), índice de pulsatilidade (IP), índice de resistência (IR) e a temperatura ambiental (TA) foram correlacionados com os espermogramas. Foram observadas correlações positivas e negativas entre as variáveis da TIV e US Doppler com as variáveis dos espermogramas e conclui-se que a TIV permite a observação de alterações precoces da temperatura do plexo e escroto; a US Doppler demonstrou correlações entre a VDF, IR e IP com qualidade do sêmen; de acordo com este estudo touros com qualidade de sêmen superior apresentaram menor impedância vascular das artérias testiculares / Brazil has the largest commercial cattle herd in the world and reached 212,8 million head in 2011. 12,3 million doses of bovine semen were sold in 2012. Effective from cows of reproductive age is 61,4 million and the use of two doses of semen per cow is estimated that 10 % of the national herd is being inseminated. Fertility is an important feature in production systems and the bull has great importance. Using infrared thermography (IRT) and Doppler ultrasonography thermoregulation and blood flow were evaluated in bulls. Two groups of six bulls were evaluated for a year and the data of thermography - global temperature plexus (GTP), global temperature of the scrotum (GTE), temperature of the left plexus (TLP), temperature of the right plexus (TRP), temperature the left scrotum (TLE), temperature of the right scrotum (TRE) and Doppler ultrasonography - peak systolic velocity (PSV ), end diastolic velocity (EDV), pulsatility index (PI), resistance index (RI) and room temperature (RT) were correlated with semen analyzes. Positive and negative correlations were found between the variables of IRT and US Doppler variables of semen analyzes and concludes that IRT allows observation of early changes of the plexus and scrotal temperature; Doppler US demonstrated correlations between EDV, RI and IP with semen quality; according to this study bulls with superior quality of semen showed lower vascular impedance of the testicular arteries
35

Utilização da termografia infravermelha para pesquisa de alterações na temperatura dos cascos de cavalos após ferrageamento a quente /

Rodrigues, Taís Casonato January 2018 (has links)
Orientador: Juliana Regina Peiró / Resumo: Sete equinos hígidos, de ambos sexos, foram utilizados para este experimento, com objeto de avaliarmos as diferenças de temperatura do casco do animal, antes e após o ferrageamento a quente, com auxílio de termógrafo infravermelho, por duas avaliações com intervalo de 45 entre elas. O teste t de Student pareado foi escolhido para análise estatista, e foram considerados valores significativos para diferentes momentos do ferrageamento quando p<0,05. Houve diferença significativa de temperatura em quase todas imagens realizadas do casco quando comparadas as temperaturas anteriores e posteriores ao ferrageamento a quente. Embora as temperaturas tenham se elevado após ferrageamento, este aumento não ultrapassou a temperatura corpórea fisiológica (37,5ºC-38,5ºC). Não houve danos ao estojo córneo como linhas de estresse e rachaduras. Não houve falha no crescimento do casco entre os ferrageamentos. Os animais não manifestaram dor, e tão pouco alteram o comportamento durante o procedimento. Os parâmetros vitais não apresentaram diferença significativa entre os momentos. Por estes resultados, é possível aventar que o ferrageamento a quente é uma prática segura e não causa danos ao casco. / Abstract: Thermography has been widely used in veterinary medicine, mainly in diagnostic, prognostic and preventive aid. The aim of this study was to observe the temperature of toracic hooves, the anterior limbs, before and after the hot fitting, with the help of a thermograph, to establish a temperature pattern after the shoeing and to infer if it can cause damages to the hoof equine. Although the forged horseshoe reaches very high temperatures, the hoof temperature rise did not exceed physiological temperature values. Based on the maintenance behavior during the procedure, maintenance of the normal values in the physical examinations and with the conservation of the hoof growth, between one shoeing and another, it is possible to infer that the hot fitting is a safe practice and does not cause damage to the hoof. / Mestre
36

Infrared thermography (IRT) for the assessment of microvascular skin blood flow in a specialist connective tissue disease unit

Howell, Kevin J. January 2009 (has links)
Aim. To establish standardised infrared thermography (IRT) within a specialist connective tissue disease unit, assessing its utility: • for the evaluation of Raynaud’s Phenomenon (RP) in clinical rheumatology and research • for the detection of active localised scleroderma (LS) lesions in paediatric patients and to develop improvements in IRT quality assurance for these medical applications. Methods. For the evaluation of RP, a protocol for cold challenge of the feet was developed and validated. IRT was applied with hand cold challenge for the assessment of response to oral vasodilator therapies in two large randomised pilot studies. An infrared thermometer technique was developed, validated against IRT, and subsequently used for the assessment of peripheral vasospasm in a twin study into the heritability of RP. The utility of inspection of thermograms for detecting clinically active LS lesions was established. A protocol was developed incorporating photography, IRT and laser Doppler flowmetry (LDF) for LS assessment, and the normal range of temperature and LD blood flow across several body sites was established in adults and children. The utility of the protocol for assessing LS activity in children was investigated. To develop quality assurance of thermography, the author contributed to the specification and validation of blackbody medical temperature reference sources, and published guidelines for procuring and commissioning a medical thermal imager. Results. Healthy controls had a higher mean toe temperature than RP patients (at baseline 29.2 ± 1.5oC v 24.8 ± 1.5oC [mean ± SD], p < 0.01; t-test). IRT demonstrated improved finger rewarming 10 minutes after cold challenge in primary RP patients 11 treated with fluoxetine compared with those treated with nifedipine (58.8% v 43.1%, p=0.03; t-test). IRT showed no such improvement in finger rewarming over nifedipine in patients treated with losartan. In a hospital setting, an infrared thermometer technique performed similarly to IRT with cold challenge for the detection of RP: the sensitivity of IRT was 83%, whereas for the infrared thermometer it was 89%. The specificity of both instruments was 84%. In a population setting using the infrared thermometer both baseline finger temperature and rewarming after ten minutes were significantly lower for RP subjects than for controls (for baseline: 28.3oC v 30.0oC, p < 0.01, t-test; for rewarming: 4.6oC v 5.3oC, p < 0.05, t-test). Infrared thermometer measurements in monozygotic and dizygotic twin pairs revealed a heritability of 65% for baseline finger temperature, 35% for fall after cold challenge, and 24% for rewarming over ten minutes. In the larger of two published studies on the inspection of thermograms for detecting clinically active LS, sensitivity was 92%, and specificity was 68%. In lesions imaged within 2 years of onset, sensitivity was 81% and specificity 88%. Validation of a protocol combining IRT and LDF measurements revealed that, in adult controls, the mean temperature difference between the two sides of the body was less than 0.5oC at all body regions. Mean differences in contralateral LD flux were less than 40% at all body sites. Variability in LD and IRT readings due to experimental factors was acceptably small in comparison to the physiological differences recorded. Applying the protocol in children with LS, the median relative increase in LD blood flow in clinically active lesions (compared with blood flow in contralateral unaffected skin) was 89% (range -69% to +449%), whereas the median flow increase in clinically inactive lesions was 11% (range -46% to +302%), p < 0.001. Using IRT, the median temperature difference between clinically active lesions and contralateral unaffected skin was 0.5°C (range -0.1°C to +4.1°C), whereas the median temperature difference for clinically inactive plaques was 0.3oC (range -1.9°C to +2.7°C), p=0.024. 12 In hand cold challenge measurements made at the Royal Free Hospital, application of the medical blackbody temperature reference sources reduced the overall uncertainty in temperature readings by a factor of about 4, from typically ±2°C to ±0.5°C. Conclusion. IRT or infrared thermometer data on skin temperature before and after cold challenge affords RP studies an important element of objectivity. RP detected in a population setting exhibits milder vasospasm than RP recruited from hospital patients, and thus the results of research performed at specialist centres may not be translatable to community settings. Inspection of thermograms is an effective method for the detection of clinically active LS, although LDF performed better than IRT using a protocol reliant on objective measurements from small regions of interest. IRT and infrared thermometry were generally less effective at discriminating between healthy and diseased subjects in situations where the temperature difference between groups was small (<2°C). The introduction of temperature reference sources, which reduce uncertainty in radiometric measurements to the order of 0.5°C, would increase the utility of IRT in settings where the temperature change associated with disease is small.
37

Utilização da termografia infravermelha para pesquisa de alterações na temperatura dos cascos de cavalos após ferrageamento a quente / Use of infrared thermography for research of change in temperature of horses hooves after hot shoeing

Rodrigues, Taís Casonato 27 February 2018 (has links)
Submitted by TAÍS CASONATO RODRIGUES null (tais_casonato@yahoo.com.br) on 2018-03-05T21:15:05Z No. of bitstreams: 1 Dissertação final 23.02 Pdf aprovação.pdf: 1150748 bytes, checksum: bc5df633130f674e214de7cf2191a095 (MD5) / Approved for entry into archive by Isabel Pereira de Matos null (isabel@fmva.unesp.br) on 2018-03-06T19:15:25Z (GMT) No. of bitstreams: 1 rodrigues_tc_me_araca_int.pdf: 1150748 bytes, checksum: bc5df633130f674e214de7cf2191a095 (MD5) / Made available in DSpace on 2018-03-06T19:15:25Z (GMT). No. of bitstreams: 1 rodrigues_tc_me_araca_int.pdf: 1150748 bytes, checksum: bc5df633130f674e214de7cf2191a095 (MD5) Previous issue date: 2018-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Sete equinos hígidos, de ambos sexos, foram utilizados para este experimento, com objeto de avaliarmos as diferenças de temperatura do casco do animal, antes e após o ferrageamento a quente, com auxílio de termógrafo infravermelho, por duas avaliações com intervalo de 45 entre elas. O teste t de Student pareado foi escolhido para análise estatista, e foram considerados valores significativos para diferentes momentos do ferrageamento quando p<0,05. Houve diferença significativa de temperatura em quase todas imagens realizadas do casco quando comparadas as temperaturas anteriores e posteriores ao ferrageamento a quente. Embora as temperaturas tenham se elevado após ferrageamento, este aumento não ultrapassou a temperatura corpórea fisiológica (37,5ºC-38,5ºC). Não houve danos ao estojo córneo como linhas de estresse e rachaduras. Não houve falha no crescimento do casco entre os ferrageamentos. Os animais não manifestaram dor, e tão pouco alteram o comportamento durante o procedimento. Os parâmetros vitais não apresentaram diferença significativa entre os momentos. Por estes resultados, é possível aventar que o ferrageamento a quente é uma prática segura e não causa danos ao casco. / Thermography has been widely used in veterinary medicine, mainly in diagnostic, prognostic and preventive aid. The aim of this study was to observe the temperature of toracic hooves, the anterior limbs, before and after the hot fitting, with the help of a thermograph, to establish a temperature pattern after the shoeing and to infer if it can cause damages to the hoof equine. Although the forged horseshoe reaches very high temperatures, the hoof temperature rise did not exceed physiological temperature values. Based on the maintenance behavior during the procedure, maintenance of the normal values in the physical examinations and with the conservation of the hoof growth, between one shoeing and another, it is possible to infer that the hot fitting is a safe practice and does not cause damage to the hoof.
38

Ensaio sobre o uso da termografia infravermelha na avaliação da vitalidade pulpar in vivo / The use of infrared thermographic imaging for pulp vitality evaluation in vivo

Isabelle Elias 08 October 2008 (has links)
Atualmente, sabe-se que determinar a vitalidade pulpar testando apenas a sua resposta sensorial nervosa, através de testes térmicos ou elétricos, é discutível, pois tais procedimentos não são suficientemente sensíveis para determinar, em definitivo, o real grau de envolvimento pulpar. Além disso, a vitalidade da polpa não depende apenas de seu suprimento nervoso, mas de seu suprimento sanguíneo. Outro fator a considerar com relação ao diagnóstico pulpar, deve-se à possibilidade da ocorrência de respostas pouco confiáveis em pacientes excessivamente ansiosos ao tratamento odontológico, independente do estímulo empregado e da intensidade do teste. O diagnóstico da vitalidade pulpar através de meios de mensuração da temperatura da coroa do dente, como a termografia infravermelha, que avalia a distribuição de temperatura num corpo através da radiação emitida pela sua superfície, surge como possibilidade para superar as desvantagens dos testes de sensibilidade, como a necessidade da estimulação, as variáveis decorrentes da espessura de dentinaesmalte dos dentes, a idade dos pacientes, a condição da estrutura dentária, entre outras. Esta pesquisa verificou a aplicabilidade da imagem infravermelha na análise da queda de temperatura produzida pelo teste térmico com gás refrigerante e a viabilidade como recurso semiotécnico para diagnóstico endodôntico. Para tal, foram analisados quatro dentes portadores de polpa vital e dois dentes tratados endodonticamente. A metodologia utilizada avaliou, através da imagem térmica, a temperatura da superfície coronária submetidos à queda de temperatura, com e sem a utilização do isolamento absoluto. Os resultados não mostraram diferença significante entre os dentes estudados, no que diz respeito à temperatura da superfície coronária e que a utilização do isolamento absoluto também não alterou os resultados. A metodologia proposta neste estudo mostrou-se altamente eficaz para a análise de mudanças térmicas na superfície dentária. No entanto, novos estudos devem ser realizados para que a termografia infravermelha possa se tornar um recurso viável para utilização em Endodontia. / Nowadays, it is known that the determination of the pulp vitality testing only its nerve sensorial response through thermal or electrical tests is discussable because those procedures are not sufficiently sensitive to determine the degree of pulp involvement. Besides the vitality of the pulp does not only depend on its nerve condition, but on its blood supply too. Another factor to consider during the pulp diagnostic, independently of the nature of stimulus or their intensity, is the possibility to occur non reliable responses in excessively anxious patients face to the dentistry treatment. The diagnosis of the pulp vitality by the measurement of the dental crown temperature such as the infrared thermography (which evaluates the temperature distribution in a body through the radiation emitted by its surface) arises as a possibility to overcome the sensitivity tests disadvantages, for example: the stimulation necessity, the variants due to the thickness of the dentin and enamel, the age, the condition of the dental structure and etc. This study evaluated the applicability of the infrared thermography test in the analysis of temperatures decline produced by thermal test using cold spray, and its viability as an aid for the endodontic diagnostic. Using thermal imaging, this methodology analyzed the temperature of the crowns surface of four teeth with vitality and two endodontically treated teeth when submitted to the cold test with and without the use of rubber dam. The results did not show a significant difference between teeth conditions with regard to the crowns surface temperature and the use of rubber dam did not affect these results. The proposed methodology used in this study showed to be highly efficient to analyzing the thermal changes on the dental surface; however new studies must be performed to turn infrared thermography a practicable aid into the endodontic practice.
39

Použití termovizní kamery v měřicí technice. / Using the infrared camera in the measuring technique.

Jakl, Oldřich January 2013 (has links)
This diploma thesis is focused on using infrared camera within methods of active thermography. The first part of work is an introduction to the passive and active thermography; and about four basic methods of active thermography: step heating themography, Lock-in thermography and pulse phase thermography. The second part is a proposal of experimental working place. There are also presented results of practical implementation pulse and pulse phase methods tested for application of detection of subsurface defect.
40

Digital Infrared Thermal Imaging and its use in Domestic and Non-Domestic Species

Bowers, Susan Denise 15 December 2012 (has links)
Digital infrared thermal imaging (DITI) is a non-invasive diagnostic technique that is used to detect symmetry and asymmetry of surface temperature gradients. DITI can examine many different aspects of thermal physiology and diagnose injury and disease. The objectives of this study were (1) to investigate the use of DITI to determine whether differences in temperature gradients exist between late gestation and non-pregnant mares, (2) to evaluate whether velvet antler (VA) temperature gradients, as measured by DITI would pattern VA growth, and (3) to determine if “normal” temperature gradients of the foot exist among elephants as detected using DITI. To investigate these objectives, three experiments were conducted to determine the value of DITI for research on mammals. Results obtained from the first study indicate DITI was able to detect pregnancy in the horse during late gestation. In the second study DITI successfully patterned the growth and hardening of VA. While in the third study DITI demonstrated its value as a tool to increase overall welfare for captive elephants. In summary these studies suggests that DITI may have value in conducting research with domestic and non-domestic species that are not able to be restrained.

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