scholarly journals Analytical and experimental solution for heat source located under skin: chest tumor detection via IR camera

2021 ◽  
Author(s):  
Maryam Rastgar-Jazi
Keyword(s):  
Heat Source ◽  
The Body ◽  
Bioheat Equation ◽  
Ir Camera ◽  
Steady State Condition ◽  
Tissue Phantom ◽  
Female Breast ◽  
Higher Temperature ◽  
Body Surface Temperature ◽  
Set Up

Infrared (IR) imaging could be used as both noninvasive and nonionizing technology. Utilizing IR camera, it is possible to measure skin temperature with the aim of finding any superficial tumors. Since tumors are highly vascular and usually have a higher temperature than the rest of the body, using thermograms, it is possible to assess various tumor parameters, such as depth, intensity, and radius. In this study, we have developed an analytical method to detect tumor parameters in both spherical and cubical tissues to represent female breast and male chest tissue. This includes development of analytical solution for solving inverse bio-heat problem as well as laboratory set up for further validation of the analytical achievements. The models were developed by solving Penne’s Bioheat equation for each tissue under certain conditions and two main assumptions: 1. The tumor was assumed as separate heat source; 2. The developed model does not change with time (steady state condition). Finally, the analytical findings were validated by utilizing a laboratory test set-up containing an IR camera, 1% Agar solution (tissue phantom), and a heater of variable powers. The models were set to test by adjusting the heater (0.9W) in various depth and imaging the tissue phantom. Comparing the analytically obtained results with the experimental results, it can be concluded that the method is able to detect superficial tumors of small size only by measuring the body surface temperature and ambient temperature.

scholarly journals Analytical and experimental solution for heat source located under skin: chest tumor detection via IR camera

2021 ◽  
Author(s):  
Maryam Rastgar-Jazi
Keyword(s):  
Heat Source ◽  
The Body ◽  
Bioheat Equation ◽  
Ir Camera ◽  
Steady State Condition ◽  
Tissue Phantom ◽  
Female Breast ◽  
Higher Temperature ◽  
Body Surface Temperature ◽  
Set Up

Infrared (IR) imaging could be used as both noninvasive and nonionizing technology. Utilizing IR camera, it is possible to measure skin temperature with the aim of finding any superficial tumors. Since tumors are highly vascular and usually have a higher temperature than the rest of the body, using thermograms, it is possible to assess various tumor parameters, such as depth, intensity, and radius. In this study, we have developed an analytical method to detect tumor parameters in both spherical and cubical tissues to represent female breast and male chest tissue. This includes development of analytical solution for solving inverse bio-heat problem as well as laboratory set up for further validation of the analytical achievements. The models were developed by solving Penne’s Bioheat equation for each tissue under certain conditions and two main assumptions: 1. The tumor was assumed as separate heat source; 2. The developed model does not change with time (steady state condition). Finally, the analytical findings were validated by utilizing a laboratory test set-up containing an IR camera, 1% Agar solution (tissue phantom), and a heater of variable powers. The models were set to test by adjusting the heater (0.9W) in various depth and imaging the tissue phantom. Comparing the analytically obtained results with the experimental results, it can be concluded that the method is able to detect superficial tumors of small size only by measuring the body surface temperature and ambient temperature.

scholarly journals Thermal Characteristics of Breast Surface Temperature in Healthy Women

2021 ◽  
Vol 18 (3) ◽  
pp. 1097
Author(s):  
Anna Lubkowska ◽  
Monika Chudecka
Keyword(s):  
Mammary Gland ◽  
Temperature Distribution ◽  
Surface Temperature ◽  
Thermal Characteristics ◽  
The Body ◽  
Imaging Method ◽  
Infrared Thermal Imaging ◽  
Ir Camera ◽  
Entire Area ◽  
Healthy Women

Thermography is widely used in the medical field, including in the detection of breast disorders. The aim of the research was to characterize the range of breast surface temperature values, taking into account the entire area of the mammary gland and, independently, the nipple, in healthy women. An additional aim was to assess the symmetry of the breast temperature distribution (using an IR camera) and the correlation of temperatures with the content of adipose tissue. Thermograms were made for the right and left breasts, each time delineating the area of the entire breast and a separate area of the nipple, chest, and abdomen. Analyzing the intergroup differences in temperature of selected body areas (Tmean), it was shown that, in all cases, they were significantly higher in younger women. Statistical analysis showed no significant differences between breast and nipple temperatures in relation to the body sides. The highest temperatures within the mammary gland were recorded for the nipple area. The use of the high-resolution digital infrared thermal imaging method in early and screening preventive diagnoses of changes in the mammary gland requires individual interpretation of the results, taking into account the assessment of the physiological pattern of temperature distribution in both breasts.

scholarly journals Analysis of hyperbolic Pennes bioheat equation in perfused homogeneous biological tissue subject to the instantaneous moving heat source

2021 ◽  
Vol 3 (4) ◽  
Author(s):  
Ali Kabiri ◽  
Mohammad Reza Talaee
Keyword(s):  
Heat Source ◽  
Closed Form ◽  
Method Comparison ◽  
Closed Form Solution ◽  
Form Solution ◽  
Temperature Profiles ◽  
Moving Heat Source ◽  
Bioheat Equation ◽  
Perfusion Rate

AbstractThe one-dimensional hyperbolic Pennes bioheat equation under instantaneous moving heat source is solved analytically based on the Eigenvalue method. Comparison with results of in vivo experiments performed earlier by other authors shows the excellent prediction of the presented closed-form solution. We present three examples for calculating the Arrhenius equation to predict the tissue thermal damage analysis with our solution, i.e., characteristics of skin, liver, and kidney are modeled by using their thermophysical properties. Furthermore, the effects of moving velocity and perfusion rate on temperature profiles and thermal tissue damage are investigated. Results illustrate that the perfusion rate plays the cooling role in the heating source moving path. Also, increasing the moving velocity leads to a decrease in absorbed heat and temperature profiles. The closed-form analytical solution could be applied to verify the numerical heating model and optimize surgery planning parameters.

Seasonal changes in the body surface temperature of Hanwoo (Bos taurus coreanae) steers

2014 ◽  
Vol 54 (9) ◽  
pp. 1476 ◽  
Author(s):  
N. Y. Kim ◽  
S. J. Kim ◽  
J. H. Park ◽  
M. R. Oh ◽  
S. Y. Jang ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Ambient Temperature ◽  
Body Surface ◽  
Seasonal Changes ◽  
Bos Taurus ◽  
The Body ◽  
Body Regions ◽  
Extreme Cold ◽  
Body Surface Temperature ◽  
Average Body

The present study aimed to gather basic information on measuring body surface temperature (BST) of cattle by using infrared thermography (IRT) and find out whether BST measurement is a useful method to detect thermal balance of livestock. Twenty-seven Hanwoo steers were examined in a field trial. The BST of five body regions (eye, nose, horn, ear, rear) was measured five times daily, with three replicates, during 3 days each season. Body surface temperature of cattle is directly affected by ambient temperature and humidity, and showed different ranges for each region. The BSTs of nose, horns and ears were significantly (P < 0.05) lower than those of eyes and rear area. Rear-area BST was significantly lower than eye-area BST when the ambient temperature was low (P < 0.05). Eye BST (EBST) was highest (P < 0.05) and the least variable of all BSTs measured. Therefore, the eye area of cattle was the most thermostable part of the body. There were significant (P < 0.05) differences among seasonal EBSTs of steers. The EBST range was highest in the summer (37.9–42.2°C), followed by autumn (34.3–37.4°C), spring (33.8–36.5°C) and winter (29.8–32.6°C). During extreme cold, EBST showed a large standard deviation. During conditions of extreme heat, EBST was above the average body temperature of cattle. The results of the present study indicated that BST well reflects the thermal circumstances surrounding animals and may be used as one of the effective tools for precision cattle farming.

External work in level and grade walking on a motor-driven treadmill

1960 ◽  
Vol 15 (5) ◽  
pp. 759-763 ◽  
Author(s):  
J. W. Snellen
Keyword(s):  
Heat Loss ◽  
Heat Production ◽  
Total Energy Expenditure ◽  
The Body ◽  
External Work ◽  
Thermal Exchange ◽  
Level Walking ◽  
The Subject ◽  
Set Up ◽  
Physical Laws

When studying a walking subject's thermal exchange with the environment, it is essential to know whether in level walking any part of the total energy expenditure is converted into external mechanical work and whether in grade walking the amount of the external work is predictable from physical laws. For this purpose an experiment was set up in which a subject walked on a motor-driven treadmill in a climatic room. In each series of measurements a subject walked uphill for 3 hours and on the level for another hour. Metabolism was kept equal in both situations. Air and wall temperatures were adjusted to the observed weighted skin temperature in order to avoid any heat exchange by radiation and convection. Heat loss by evaporation was derived from the weight loss of the subject. All measurements were carried out in a state of thermal equilibrium. In grade walking there was a difference between heat production and heat loss by evaporation. This difference equaled the caloric equivalent of the product of body weight and gained height. In level walking the heat production equaled heat loss. Hence it was concluded that in level walking all the energy is converted into heat inside the body. Submitted on April 26, 1960

Performance Tests of a 4,1x4,1mm2 SiC LCVJFET for a DC/DC Boost Converter Application

2011 ◽  
Vol 679-680 ◽  
pp. 722-725 ◽  
Author(s):  
Georg Tolstoy ◽  
Dimosthenis Peftitsis ◽  
Jacek Rabkowski ◽  
Hans Peter Nee
Keyword(s):  
Voltage Drop ◽  
Short Circuit ◽  
Boost Converter ◽  
The Body ◽  
Switching Loss ◽  
Lateral Channel ◽  
Short Circuit Test ◽  
Higher Temperature ◽  
High Temperature Operation ◽  
State Resistance

A 4.1x4.1mm2, 100mΩ 1,2kV lateral channel vertical junction field effect transistor (LCVJFET) built in silicon carbide (SiC) from SiCED, to use as the active switch component in a high-temperature operation DC/DC-boost converter, has been investigated. The switching loss for room temperature (RT) and on-state resistance (Ron) for RT up to 170°C is investigated. Since the SiC VJFET has a buried body diode it is also ideal to use instead of a switch and diode setup. The voltage drop over the body diode decreases slightly with a higher temperature. A short-circuit test has also been conducted, which shows a high ruggedness.

On one-dimensional unsteady flow at infinite Mach number

1968 ◽  
Vol 304 (1478) ◽  
pp. 255-273 ◽  
Keyword(s):  
Asymptotic Expansion ◽  
Blast Wave ◽  
Outer Part ◽  
The Body ◽  
Viscous Boundary Layer ◽  
Outer Flow ◽  
Hypersonic Speeds ◽  
Set Up ◽  
Viscous Boundary ◽  
Infinite Set

The use of the blast-wave analogy, as an aid to the interpretation of experimental data on the motion of a fluid past an obstacle at hypersonic speeds, has led to the theoretical study of its role in an asymptotic expansion of the solution to the governing equations at large distances downstream of the body. In all attempts to set up such an expansion it has proved necessary to divide the flow régime into two parts, an outer part dominated by the blast wave and an inner part consisting of streamlines which, originally, pass close by the body. The matching of these two regions is apparently only possible if a certain integral vanishes. In the present paper a numerical integration, in one particular set of circumstances, is carried out to test the validity of the asymptotic expansion proposed. Formally, an unsteady problem is tackled, for ease of computation, but the steady analogue follows immediately and is of exactly the form discussed in the earlier investigations. It is found that the main results are in line with the theory and that the integral in question is indistinguishable from zero. However, a deeper investigation of the asymptotic expansion shows that, for an expansion of the type envisaged, an infinite set of integrals must each vanish. The next integral does not appear to be zero according to our computations but this result is not believed to be conclusive. Assuming that all the integrals do vanish, then it appears that the inner layer, which although inviscid, has many of the characteristics of a viscous boundary layer, has the addi­tional, surprising property that it can exert no direct influence on the outer flow at large distances downstream of the body.

Transient Temperature Involving Oscillatory Heat Source With Application in Fretting Contact

2007 ◽  
Vol 129 (3) ◽  
pp. 517-527 ◽  
Author(s):  
Jun Wen ◽  
M. M. Khonsari
Keyword(s):  
Heat Source ◽  
Oscillation Amplitude ◽  
The Body ◽  
Transient Temperature ◽  
Dimensionless Frequency ◽  
Heat Sources ◽  
Infinite Body ◽  
Fitting Method ◽  
Wide Range ◽  
Analytical Expressions

An analytical approach for treating problems involving oscillatory heat source is presented. The transient temperature profile involving circular, rectangular, and parabolic heat sources undergoing oscillatory motion on a semi-infinite body is determined by integrating the instantaneous solution for a point heat source throughout the area where the heat source acts with an assumption that the body takes all the heat. An efficient algorithm for solving the governing equations is developed. The results of a series simulations are presented, covering a wide range of operating parameters including a new dimensionless frequency ω¯=ωl2∕4α and the dimensionless oscillation amplitude A¯=A∕l, whose product can be interpreted as the Peclet number involving oscillatory heat source, Pe=ω¯A¯. Application of the present method to fretting contact is presented. The predicted temperature is in good agreement with published literature. Furthermore, analytical expressions for predicting the maximum surface temperature for different heat sources are provided by a surface-fitting method based on an extensive number of simulations.

scholarly journals Weavers & Warriors? Gender and Online Identity in 1997 and 2007 V1.0

2008 ◽  
Vol 2 (2) ◽  
Author(s):  
Deirdre Ruane
Keyword(s):  
Preliminary Investigation ◽  
The Body ◽  
Internet Technology ◽  
Online Identity ◽  
Men And Women ◽  
Online Interactions ◽  
And Performance ◽  
And Gender ◽  
Set Up ◽  
Active Exploration

In 1997 the Internet was seen by many as a tool for radical reinterpretation of physicality and gender. Cybertheorists predicted we would leave our bodies behind and interact online as disembodied minds, and that the technology would reshape the way we saw ourselves. However, physicality has proved to be an inextricable part of all our interactions. Changing Internet technology has allowed Net users to find a myriad ways to perform and express their gender online. In this paper I consider attitudes to gender on the Net in 1997, when the main concerns were the imbalance between men and women online and whether it was possible or desirable to bring the body into online interactions. In much of the discourse surrounding gender online, a simple binary was assumed to exist. I go on to consider the extent to which those attitudes have changed today. Through my own experience of setting up a women’s community on Livejournal, and my observations of a men’s community set up in response, I conclude that though traditional attitudes to gender have largely translated to the Net and the binary is still the default view, some shifts have occurred. For example, between 1997 and today there seems to have been a fundamental change in perceptions of women’s attitudes to adversarial debate, and an increase in awareness of genders beyond the binary. In addition, experience and preliminary investigation lead me toward a hypothesis that today’s female-identified Net users are engaged in more conscious and active exploration and performance of their gender online than male-identified users are.

scholarly journals Pengaruh Waktu Istirahat Berbeda Sebelum Proses Pemotongan Terhadap Respon Suhu Permukaan Tubuh Sapi Brahman Cross

2021 ◽  
Vol 2 (1) ◽  
pp. 27-32
Author(s):  
M. Adhyatma ◽  
Gayuh Syaikhullah ◽  
Himmatul Khasanah
Keyword(s):  
Surface Temperature ◽  
Body Surface ◽  
Rest Period ◽  
The Body ◽  
Surface Temperature Change ◽  
Rest Periods ◽  
Randomized Design ◽  
Humidity Index ◽  
Body Surface Temperature ◽  
Data Collections

his study aims to assess the physiological response through body surface temperature of Brahman Cross beef by giving different rest periods. This study used 24 Brahman Cross cattle in several slaughterhouses in West Java. Observation of microclimatic conditions includes temperature, humidity, THI (temperature-humidity index). Data collections of livestock body surface temperature was carried out when the cattle arrive at the slaughterhouse, while they are in the holding pen and the restraining box. Comparative tests were carried out on the surface temperature of cows under different conditions using a completely randomized design (CRD). This study showed that the body surface temperature was still in the normal range, between 30.89-36.75 °C. Analysis of variance showed that different rest periods had a significant effect  (P <0.05) on body surface temperature change in the eye area in the three pre-cutting stages. Providing a 24 hours rest period resulted in lower stress response in livestock.

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