Página 1 dos resultados de 486 itens digitais encontrados em 0.003 segundos

Monitoring feet temperature using thermography

Bento, David; Pereira, Ana I.; Monteiro, Fernando C.
Fonte: Taylor & Francis Group Publicador: Taylor & Francis Group
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
37.18%
Studies show that regular monitoring of feet temperature may limit the incidence of disabling conditions such as foot ulcers and lower-limb amputations. Infrared thermometry and liquid crystal thermography were identified as the leading technologies in use today. In this study, we analysed the maximum temperature and tested some mathematical models for the foot temperature distribution.

On the use of infrared thermography in studies with air curtain devices

Neto, Luís P. C.; Silva, M. C. Gameiro; Costa, José J.
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
Relevância na Pesquisa
37.18%
Among the different existing methods to characterise the aerodynamic sealing effect provided by an air curtain device placed over the opening between two contiguous compartments, infrared thermography has revealed to be a very useful tool. Besides allowing the capture, in an expedite way, of instantaneous images of the temperature field in the neighbourhood of the door, the technique hereon described has other advantages, in terms of quick and easy setup, low intrusive character and liability of obtained results.; http://www.sciencedirect.com/science/article/B6V2V-4JN2NWG-3/1/777518b08aa97d940a76d5961da92221

Programa de suplementação de luz e relações entre variáveis fisiológicas e termográficas de bezerros em aleitamento em clima quente; Program of supplementary light and the relationship between physiological and thermography variables of suckling calves in hot weather

Mac-Lean, Priscilla Ayleen Bustos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 23/03/2012 PT
Relevância na Pesquisa
37.46%
Este trabalho teve como objetivo avaliar um programa de suplementação de luz no desenvolvimento, desempenho e comportamento de bezerros em aleitamento e o uso da câmera termográfica como método para avaliação de variáveis fisiológicas por método não invasivo. O experimento foi realizado na Agência Paulista de Tecnologia dos Agronegócios - APTA, em Ribeirão Preto, SP. Foram utilizados 20 bezerros Jersey e mestiços da raça, divididos em dois tratamentos, com e sem programa de suplementação de luz artificial. O programa de suplementação de luz artificial consistiu em 6 h de luz artificial (das 00:00 as 6:00 h), completando 18 horas de luz por dia. Foram avaliadas as características fisiológicas dos animais: frequência respiratória (FR), temperatura da superfície do pelame (TSP), temperatura auricular (TA), temperatura caudal (TC) e temperatura retal (TR). A ingestão de ração e água também foi estudada. Avaliou-se também o desenvolvimento dos animais através dos ganhos médios diários de peso (GPMD), de altura, de comprimento e de perímetro torácico (PT). Foi estudado o comportamento social e ingestivo dos animais. E por fim, através de cinco coletas de dados em dias de alta entalpia, onde os dados foram registrados em quatro horários (18:00...

Estudo da distribuição térmica da superfície cutânea facial por meio de termografia infravermelha: termoanatomia da face; Study of the facial surface skin thermal distribution by infrared thermography: facial thermoanatomy

Haddad, Denise Sabbagh
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/12/2014 PT
Relevância na Pesquisa
37.18%
Pelo fato da face ser uma estrutura que envolve multissistemas, ela é considerada anatomica e funcionalmente muito complexa em sua avaliação clínica. Muitos diagnósticos de doenças que afetam a região facial são realizados por meio de métodos de imagem, entretanto, as técnicas convencionais são incompletas, pois apresentam um déficit de informações em relação aos aspectos funcionais, relativos à microcirculação regional e o sistema nervoso autônomo. Para documentação objetiva destas alterações, a termografia por imagem infravermelha tem sido proposta como método auxiliar diagnóstico. O objetivo deste estudo foi identificar, mapear e quantificar pontos de referência baseados na termoanatomia da face, a partir de gradientes térmicos, em uma população adulta. A amostra constituiu-se por 161 voluntários, ambos os gêneros, entre 26 e 84 anos (63 ±15 anos). Foram identificados 28 pontos de referência termoanatômicos fixos em 94,6% da amostra. A temperatura média desses pontos de referência termoanatômicos variou entre 33,3°C a 35,6°C, sendo que o melhor valor de corte para sua correta identificação na face foi acima de 34,5ºC. Não houve diferença estatística quando os comparou entre as hemifaces correspondentes e nem quanto à idade dos voluntários (?T = 0...

Scrotal Thermography and Doppler Ultrasonography of the Testicular Artery of Buffaloes Subjected to Environmental Heat Stress

Ramires Neto, Carlos; Resende, Helene Lacerda de; Monteiro, Gabriel A.; Zorzetto, Mariana F.; Sancler da Silva, Yame F. R.; Oba, Eunice
Fonte: Int Buffalo Information Ctr Publicador: Int Buffalo Information Ctr
Tipo: Artigo de Revista Científica Formato: 1145-1145
ENG
Relevância na Pesquisa
37.46%
The process of spermatic division and differentiation (spermatogenesis) occurs with intratesticular temperature lower that the corporal temperature and for that is essential that the testicular thermoregulation mechanism occurs properly. For evaluation of the scrotal surface temperature can be used the infrared thermography or testicular sensors, besides that, can be evaluated the blood flux in the spermatic cord through the Doppler ultrasonography. Therefore the objective of this study was the evaluation of the scrotal thermography and Doppler flowmetry of the testicular artery of buffaloes subjected to environmental heat stress. For that were used seven healthy buffaloes, with age of 3 and 4 years, of the Murrah breed. For the surface scrotal temperature measurement (SST, degrees C) and superficial neck temperature (SNT, degrees C) was used the infrared termography (Infra Cam (TM) of the brand FLIR Systems Inc.), then Doppler flowmetry of the testicular artery in the region of the spermatic cord through the ultrasonography (Mylab 5, Esaote (R)) and measurement of the rectal temperature (RT, degrees C). The evaluations were done in two moments: moment 1 (M1) with all the animals in the shade (Temperature=32,2 degrees C) and moment 2 (M2) after 3 hours of exposure of animals to the sun (Temperature=38...

FRP-to-masonry bond durability assessment with infrared thermography method

Ghiassi, Bahman; Silva, Sandra Monteiro; Oliveira, Daniel V.; Lourenço, Paulo B.; Bragança, L.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em //2014 ENG
Relevância na Pesquisa
37.18%
The bond behavior between FRP composites and masonry substrate plays an important role in the performance of externally bonded reinforced masonry structures. Therefore, monitoring the bond quality during the application and subsequent service life of a structure is of crucial importance for execution control and structural health monitoring. The bond quality can change during the service life of the structure due to environmental conditions. Local detachments may occur at the FRP/substrate interface, affecting the bond performance to a large extent. Therefore, the use of expedite and efficient non-destructive techniques for assessment of the bond quality and monitoring FRP delamination is of much interest. Active infrared thermography (IR) technique was used in this study for assessing the bond quality in environmentally degraded FRP-strengthened masonry elements. The applicability and accuracy of the adopted method was initially validated by localization and size quantification of artificially embedded defects in FRP-strengthened brick specimens. Then, the method was used for investigating the appearance and progression of FRP delaminations due to environmental conditions. GFRP-strengthened brick specimens were exposed to accelerated hygrothermal ageing tests and inspected periodically with the IR camera. The results showed environmental exposure may produce large progressive FRP delaminations.; Fundação para a Ciência e Tecnologia

Variations in the vulvar temperature of sows as determined by infrared thermography and its relation to ovulation

Simões, Vasco Jorge Gaspar
Fonte: Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária Publicador: Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária
Tipo: Dissertação de Mestrado
Publicado em 24/07/2012 ENG
Relevância na Pesquisa
37.18%
Dissertação de Mestrado Integrado em Medicina Veterinária; The productive results of a pig’s herd are closely related to the reproductive performance of their animals. Although in the last years several techniques were implemented to improve the reproductive efficiency of pig production, such as artificial insemination (AI) and estrus synchronization, the prediction of ovulation continues to be made with some degree of uncertainty due to the lack of an accurate, practical and fast technique. In this experimental study, we tested the applicability of infrared thermography (IRT) for ovulation prediction, based on the variations observed in the vulvar skin temperature (VST) during the proestrus and estrus period. The group tested was composed by 36 crossbred Large White x Landrace females, of which 6 gilts and 30 multiparous sows. Estrus detection was performed twice daily in the morning and afternoon, starting one day after weaning (day 1). Temperature measurements were performed every 6 hours at 0000h, 0600h, 1200h and 1800h, from day 1 to day 7. Temperature was obtained from the vulvar area and from two marked spots in the gluteal area (GST), which worked as a control. A third variable (VGT) was obtained from the differential temperature between VST and GST. Ovary ultrasonography was performed in days 5 and 6...

Thermal performance of cool facades: evaluation by Infrared Thermography

Gonçalves, Luís; Matias, Luís; Faria, Paulina
Fonte: O. Ural, V. Abrantes and A. Tadeu (eds.); ITeCons Publicador: O. Ural, V. Abrantes and A. Tadeu (eds.); ITeCons
Tipo: Artigo de Revista Científica
Publicado em /12/2014 ENG
Relevância na Pesquisa
37.46%
High reflective paints (cool paints) are used on flat roofs to reduce heat gains from the incidence of solar radiation and thus improve the thermal comfort and energy efficiency of buildings, especially in summer periods. Given the application potential of these paints on vertical surfaces, a research study has been developed to evaluate the thermal performance of reflective paints on walls under real exposure conditions. Accordingly, different reflective paints have been applied as the final coating of an ETICS type solution, on the facades of a full scale experimental cell built at LNEC campus. For being applied in an ETICS system a paint has to fulfill several requirements, whether aesthetic or functional (such as the adhesion between the coating layers or the durability of the insulation), essential for its efficient performance. Since this construction coating system is subject to a prolonged sun exposure, various problems may arise, such as paint degradation or deterioration of the thermal insulation properties, particularly when dark colors are applied. To evaluate the thermal performance of the chosen paints, the method of non-destructive analysis by Infrared Thermography was used. Thermography allows knowing the temperature distribution of facades by measuring the radiation emitted by their surfaces. To complement the thermographic diagnosis...

Assessment of techniques of massage and pumping in the treatment of breast engorgement by thermography

Heberle,Anita Batista dos Santos; Moura,Marcos Antônio Muniz de; Souza,Mauren Abreu de; Nohama,Percy
Fonte: Escola de Enfermagem de Ribeirão Preto / Universidade de São Paulo Publicador: Escola de Enfermagem de Ribeirão Preto / Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2014 EN
Relevância na Pesquisa
37.35%
OBJECTIVE: to evaluate techniques of massage and pumping in the treatment of postpartum breast engorgement through thermography. METHOD: the study was conducted in the Human Milk Bank of a hospital in Curitiba, Brazil. We randomly selected 16 lactating women with engorgement with the classification lobar, ampullary and glandular, moderate and intense. We compared the differential patterns of temperature, before and after the treatment by means of massage and pumping. RESULTS: we found a negative gradient of 0.3°C of temperature between the pre- and post-treatment in the experimental group. Breasts with intense engorgement were 0.7°C warmer when compared with moderate engorgement. CONCLUSION: massage and electromechanical pumping were superior to manual methods when evaluated by thermography. REBEC: U1111-1136-9027.

Plantar thermography is useful in the early diagnosis of diabetic neuropathy

Balbinot,Luciane Fachin; Canani,Luis Henrique; Robinson,Caroline Cabral; Achaval,Matilde; Zaro,Milton Antônio
Fonte: Faculdade de Medicina / USP Publicador: Faculdade de Medicina / USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
Relevância na Pesquisa
37.35%
OBJECTIVES: This study evaluated plantar thermography sensitivity and specificity in diagnosing diabetic polyneuropathy using cardiac tests (heart rate variability) as a reference standard because autonomic small fibers are affected first by this disease. METHODS: Seventy-nine individuals between the ages of 19 and 79 years old (28 males) were evaluated and divided into three groups: control (n = 37), pre-diabetics (n = 13) and type 2 diabetics (n = 29). The plantar images were recorded at baseline and then minutes after a provocative maneuver (Cold Stress Test) using an infrared camera that is appropriate for clinical use. Two thermographic variables were studied: the thermal recovery index and the interdigital anisothermal technique. Heart rate variability was measured in a seven-test battery that included three spectral indexes (in the frequency domain) and four Ewing tests (the Valsalva maneuver, the orthostatic test, a deep breathing test, and the orthostatic hypotension test). Other classically recommended tests were applied, including electromyography (EMG), Michigan inventory, and a clinical interview that included a neurological physical examination. RESULTS: Among the diabetic patients, the interdigital anisothermal technique alone performed better than the thermal recovery index alone...

Evaluation of healing of pressure ulcers through thermography: a preliminary study

Chaves,Maria Emília Abreu; Silva,Fernanda Souza da; Soares,Viviane Pinheiro Campos; Ferreira,Rafael Augusto Magalhães; Gomes,Flávia Sampaio Latini; Andrade,Roberto Márcio de; Pinotti,Marcos
Fonte: Sociedade Brasileira de Engenharia Biomédica Publicador: Sociedade Brasileira de Engenharia Biomédica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
Relevância na Pesquisa
37.46%
Introduction Thermography is a surface thermal radiation measurement technique whose application has been expanding in the healthcare field. The unhealed wound is a serious public health problem because it intervenes in the quality of life of patients and may cause emotional and psychological losses. The wound temperature can provide quantitative data that allow for the healing process to be monitored. The aim of this study was to verify whether thermography can be used as a method to evaluate the healing of pressure ulcers. Methods Eight participants with sacral pressure ulcers were recruited and randomly divided into two groups: A (control) and B (experimental). Both groups received standard treatment for a period of four weeks, which consisted of a daily cleaning of the pressure ulcers with physiological saline (sodium chloride 0.9%) followed by an alginate hydrogel dressing. The group B received light-emitting diode (LED) phototherapy in addition to standard treatment, three times a week, yielding a total of 12 sessions. Photographs and thermograms of each pressure ulcer were obtained in all sessions in both groups. Results Pressure ulcers treated with LED phototherapy were healed. The pressure ulcer area of group B decreased over the 12 treatment sessions...

Thermography in Neurologic Practice

Neves, Eduardo Borba; Vilaça-Alves, José; Rosa, Claudio; Reis, Victor Machado
Fonte: Bentham Open Publicador: Bentham Open
Tipo: Artigo de Revista Científica
Publicado em 26/06/2015 EN
Relevância na Pesquisa
27.6%
One kind of medical images that has been developed in the last decades is thermal images. These images are assessed by infrared cameras and have shown an exponential development in recent years. In this sense, the aim of this study was to describe possibilities of thermography usage in the neurologic practice. It was performed a systematic review in Web of Knowledge (Thompson Reuters), set in all databases which used two combination of keywords as “topic”: “thermography” and “neurology”; and “thermography” and “neurologic”. The chronological period was defined from 2000 to 2014 (the least 15 years). Among the studies included in this review, only seven were with experimental design. It is few to bring thermography as a daily tool in clinical practice. However, these studies have suggested good results. The studies of review and an analyzed patent showed that the authors consider the thermography as a diagnostic tool and they recommend its usage. It can be concluded that thermography is already used as a diagnostic and monitoring tool of patients with neuropathies, particularly in complex regional pain syndrome, and stroke. And yet, this tool has great potential for future research about its application in diagnosis of other diseases of neurological origin.

The Role of Infrared Thermography as a Non-Invasive Tool for the Detection of Lameness in Cattle

Alsaaod, Maher; Schaefer, Allan L.; Büscher, Wolfgang; Steiner, Adrian
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 18/06/2015 EN
Relevância na Pesquisa
27.6%
The use of infrared thermography for the identification of lameness in cattle has increased in recent years largely because of its non-invasive properties, ease of automation and continued cost reductions. Thermography can be used to identify and determine thermal abnormalities in animals by characterizing an increase or decrease in the surface temperature of their skin. The variation in superficial thermal patterns resulting from changes in blood flow in particular can be used to detect inflammation or injury associated with conditions such as foot lesions. Thermography has been used not only as a diagnostic tool, but also to evaluate routine farm management. Since 2000, 14 peer reviewed papers which discuss the assessment of thermography to identify and manage lameness in cattle have been published. There was a large difference in thermography performance in these reported studies. However, thermography was demonstrated to have utility for the detection of contralateral temperature difference and maximum foot temperature on areas of interest. Also apparent in these publications was that a controlled environment is an important issue that should be considered before image scanning.

Development of technical bases for using infrared thermography for nondestructive evaluation of fiber reinforced polymer composites bonded to concrete

Starnes, Monica Anastasia
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 258 p.; 14980618 bytes; 14980417 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
27.65%
Fiber-reinforced polymer (FRP) composites, in the form of pultruded laminates or built-up woven fabrics, are being used widely to strengthen existing concrete and masonry structures. The success of these materials in performing their intended functions depends, to a large extent, on how well they are bonded to themselves and to the substrate. There is a need for an efficient and reliable method to detect and characterize defects at the substrate interface and within multi-ply systems. Infrared thermography is well suited for this purpose because it is inherently sensitive to the presence of near-surface defects and can interrogate large areas efficiently. Before infrared thermography can be developed into a standard methodology, however, an understanding is needed of the effects of testing parameters and different types of defects. This dissertation focuses on establishing the potential for quantitative infrared thermography, that is, not only detecting but also characterizing subsurface flaws. Numerical and experimental methods are used to investigate the effectiveness of infrared thermography to estimate the width of subsurface flaws in fiber-reinforced polymer laminates bonded to concrete. First, a dimensional analysis of a simplified case of one-dimensional heat diffusion in an infinite half space is performed to establish the parameters that affect the thermal response of the test object.; (cont.) The results from the dimensional analysis identified the factors that had to be investigated in the parametric study. Next...

Enhanced contrast detection of subsurface defects by pulsed infrared thermography based on the fourth order statistic moment, kurtosis

Madruga Saavedra, Francisco Javier; Ibarra Castanedo, Clemente; Conde Portilla, Olga María; Maldague, Xavier P. V.; López Higuera, José Miguel
Fonte: SPIE Society of Photo-Optical Instrumentation Engineers Publicador: SPIE Society of Photo-Optical Instrumentation Engineers
Tipo: info:eu-repo/semantics/conferenceObject; publishedVersion
ENG
Relevância na Pesquisa
37.18%
The automatic detection of subsurface defects has become a desired goal in the application of non-destructive testing and evaluation techniques. In this paper, an algorithm based on the fourth order standardised statistic moment, i.e. kurtosis, is proposed for detection and/or characterization of subsurface defects having a thermal diffusivity either higher or lower than the host material. The analysis of thermographic data for the detection of defects can be reduced to the temporal statistics of the thermographic sequence. The final result provided by this algorithm is an image showing the different defects without the necessity of establishing other evaluating parameters such as the delayed time of the first image or the acquisition frequency in the analysis, which are required in other processing techniques. All the information is contained in a single image allowing to discriminate between the defect types (high o low thermal diffusivity). Synthetic data from Thermocalcà ® and experimental works using a PlexiglasTM specimen were performed showing good agreement. Processed results using synthetic and experimental data with other methods used in the field of thermography for defect detection and/or characterization are provided as well for comparison.

Quantification by signal to noise ratio of active infrared thermography data processing techniques

Hidalgo-Gato García, Rafael; Andrés Álvarez, José Ramón; López Higuera, José Miguel; Madruga Saavedra, Francisco Javier
Fonte: Scientific Research Publishing Publicador: Scientific Research Publishing
Tipo: info:eu-repo/semantics/article; publishedVersion
SPA
Relevância na Pesquisa
37.35%
In this paper, the use of a signal to noise ratio (SNR) is proposed for the quantification of the goodness of some selected processing techniques of thermographic images, such as differentiated absolute contrast, skewness and kurtosis based algorithms, pulsed phase transform, principal component analysis and thermographic signal reconstruction. A new hy- brid technique is also applied (PhAC—Phase absolute contrast), it combines three different processing techniques: phase absolute contrast, pulsed phase thermography and thermographic signal reconstruction. The quality of the results is established on the basis of the values of the parameter SNR, assessed for the present defects in the analyzed specimen, which enabled to quantify and compare their identification and the quality of the results of the employed technique.

Evaluating Gender-specificity of Sexual Arousal with Thermography in Women and Men

Huberman, JACKIE
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
37.35%
Men’s genital responses tend to be gender-specific, such that they show significantly greater arousal to their preferred gender compared to their nonpreferred gender, whereas the genital responses of androphilic women (i.e., sexually attracted to men) tend to be similar to stimuli depicting women or men (gender-nonspecific). Gender-specificity of arousal has been previously studied using short stimuli (approximately 90-second videos or audio-narratives) with genital responses assessed using vaginal photoplethysmography (VPP) in women and penile plethysmography (PPG) in men. One limitation to using these measures of genital response is that they use different scales (mV change in VPP and mm change in PPG), making it difficult to draw direct gender comparisons. In the current thesis, I examined gender-specificity of sexual arousal in women and men by measuring genital responses using thermography, which assesses similar physiological processes (i.e., temperature change associated with genital vasocongestion) in women and men. Specifically, I evaluated whether the gender-specificity of men’s and women’s genital temperature was similar to that observed for genital responses concurrently assessed using VPP (women) or PPG (men). I presented gynephilic men (i.e....

Plantar thermography is useful in the early diagnosis of diabetic neuropathy

Balbinot, Luciane Fachin; Canani, Luis Henrique; Robinson, Caroline Cabral; Achaval, Matilde; Zaro, Milton Antônio
Fonte: Universidade de São Paulo. Faculdade de Medicina Publicador: Universidade de São Paulo. Faculdade de Medicina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/12/2012 ENG
Relevância na Pesquisa
37.35%
OBJECTIVES: This study evaluated plantar thermography sensitivity and specificity in diagnosing diabetic polyneuropathy using cardiac tests (heart rate variability) as a reference standard because autonomic small fibers are affected first by this disease. METHODS: Seventy-nine individuals between the ages of 19 and 79 years old (28 males) were evaluated and divided into three groups: control (n = 37), pre-diabetics (n = 13) and type 2 diabetics (n = 29). The plantar images were recorded at baseline and then minutes after a provocative maneuver (Cold Stress Test) using an infrared camera that is appropriate for clinical use. Two thermographic variables were studied: the thermal recovery index and the interdigital anisothermal technique. Heart rate variability was measured in a seven-test battery that included three spectral indexes (in the frequency domain) and four Ewing tests (the Valsalva maneuver, the orthostatic test, a deep breathing test, and the orthostatic hypotension test). Other classically recommended tests were applied, including electromyography (EMG), Michigan inventory, and a clinical interview that included a neurological physical examination. RESULTS: Among the diabetic patients, the interdigital anisothermal technique alone performed better than the thermal recovery index alone...

Infrared video thermography: a technique for assessing cold adaptation in insects

Palmer, Christopher; Siebke, Katharina; Yeates, David
Fonte: Eaton Publishing Co Publicador: Eaton Publishing Co
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
37.35%
Insects can survive subzero temperatures by two main strategies: freeze tolerance and freeze avoidance. An array of techniques have been used to investigate the physiological limits of insects to low temperatures, such as differential scanning calorimetry, temperature-controlled cooling apparatus, thermocouples, and computer-controlled chart recording equipment. However, these techniques require animals to be stationary, precluding behavioral data. We used infrared video thermography to investigate cold adaptation in an alpine insect, expanding such investigations to include behavioral response as an indicator of physiological stress. This technique is noninvasive and provides a large amount of physiological information, such as supercooling points, lower lethal temperatures, and hemolymph melting points. Insect supercooling points in response to a constant cooling rate were variable; however, temperatures at the initiation of behavioral stress response were less variable. Assessments of supercooling points and lower lethal temperatures obtained in this way are more biologically meaningful because allowing unhindered movement of insects more closely resembles natural environments.

Particle collision during the tribo-electrostatic beneficiation of fly ash based on infrared thermography

Li,H.S.; Chen,Y.H.; Wu,K.B.; Zhang,X.X.
Fonte: Journal of the Southern African Institute of Mining and Metallurgy Publicador: Journal of the Southern African Institute of Mining and Metallurgy
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
Relevância na Pesquisa
37.46%
Tribo-electrostatic beneficiation is effective for separating unburned carbon from fly ash. During the process, the fly ash particles become charged owing to friction and collision inside a tribo device. The intensity of friction and collision between particles can be deduced from the tribo device temperature field, obtained by infrared thermography. The purpose of this research was to establish whether an appropriate configuration of tribo device models can be obtained from particle collision experiments using infrared thermography. An experimental set-up was configured to study tribo devices with different arrangements and spacing of the friction rods, and the effect that this has on interparticle collision and the tribo-electrostatic beneficiation process. The experimental material was fly ash particles with a size range from 38 µm to 74 µm and loss on ignition (LOI) 12.65%. The operating conditions were electric field voltage 40 kV and the air flux ranged from 12 to 24 m³/h. The results show that the temperature inside the tribo devices is directly proportional to air flux and particle collision rate. The arrangement and spacing of the friction rods has an important effect on the temperature field distribution. An equilateral triangular arrangement with 20 mm spacing significantly increases the temperature value and collision probability. The optimum operating parameters were established through tribo-electrostatic beneficiation experiments on the fly ash...