thermal distribution
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2021 ◽  
Vol 15 (1) ◽  
pp. 105-114
Author(s):  
Vahid R. Nafisi ◽  
Roshanak Ghods

Background: In Persian Medicine (PM), measuring the wrist temperature/humidity and pulse is one of the main methods for determining a person's health status and temperament. An important problem is the dependence of the diagnosis on the physician's interpretation of the above-mentioned criteria. Perhaps this is one reason why this method has yet to be combined with modern medical methods. Also, sometimes there is a need to use PM to diagnose patients remotely, especially during a pandemic. This brings up the question of how to implement PM into a telecare system. This study addresses these concerns and outlines a system for measuring pulse signals and temperament detection based on PM. Methods: A system was designed and clinically implemented based on PM that uses data from recorded thermal distribution, a temperament questionnaire, and a customized device that logs the pulse waves on the wrist. This system was used for patient care via telecare. Results: The temperaments of 34 participants were assessed by a PM specialist using the standardized Mojahedi Mizaj Questionnaire (MMQ). Thermal images of the wrist in the supine position (named Malmas in PM), the back of the hand, and the entire face were also recorded under the supervision of the physician. Also, the wrist pulse waves were evaluated by a customized pulse measurement device. Finally, the collected data could be sent to a physician via a telecare system for further interpretation and prescription of medications. Conclusion: This preliminary study focused on the implementation of a combinational hardware-software system for patient assessment based on PM. It appears that the design and construction of a customized device that can measure the pulse waves, and some other criteria, according to PM, is possible and can decrease the dependency of the diagnostic to PM specialists. Thus, it can be incorporated into a telemedicine system.


2021 ◽  
Vol 1199 (1) ◽  
pp. 012009
Author(s):  
K Raz ◽  
Z Chval ◽  
M Habrman ◽  
A Milsimerova

Abstract This paper deals with the usage of the injection mould made from the plastic material. This technology is rapidly decreasing the time, necessary to the production of the prototype. This attribute takes nowadays a key role in the industry, especially in the automotive. Technology of using injection moulds from the plastic material (produced by additive technologies) has advantages in the decreasing of the time demands and cost reduction during the production of the prototype part. Unfortunately, plastic moulds have worse surface quality, lower lifetime of the mould (measured in number of produced parts) and more difficulties of moulding process regulation with respect to the metal moulds. This paper is focused on the injection process and it is describing the thermal distribution and specification of the comparable plastic specimen during injection into the metal and plastic mould. The results are the temperature and cycle-times comparisons. The effectivity of cooling is also compared in this work. It is obvious, that the plastic mould has worse results compared to the metal mould. However, this is clearly balanced by the speed of production and price of plastic mould. The prototype of the plastic mould was made from the material PA12GB with usage of 3D printer HP MJF4200


2021 ◽  
Author(s):  
Syed Farhan Raza ◽  
Sarmad Ali Khan ◽  
Muhammad Farhan ◽  
Naveed Ahmed ◽  
Muhammad Salman Habib ◽  
...  

Abstract Friction stir welding (FSW) is an eco-friendly and solid-state joining technology. Due to this reason, industries are keenly adopting this joining process in their various applications e.g., automobile, aerospace, marine, etc. Several materials have already been welded by FSW including aluminum, copper, steel, alloys of these materials, plastics, composites, and list are still going on. Few researchers have welded the brass using FSW. In this research, yellow brass 405-20 is welded with FSW for the very first time. Thermal distribution during FSW of brass was recorded via both simulations and experiments. Moreover, ultimate tensile strength was also measured numerically with its validation from its empirical counterpart. Finally, hardness was measured numerically in the form of compressive strength of welded brass, and it was also validated experimentally. Three aspects of validated simulations were never studied for brass 405-20 before and finally a good and close match was found between results from both simulations and experiments.


2021 ◽  
Author(s):  
Keeyoung Son ◽  
Seongguk Kim ◽  
Minsu Kim ◽  
Daehwan Lho ◽  
Keunwoo Kim ◽  
...  

2021 ◽  
Vol 12 (4) ◽  
pp. 4637-4648

Dental implants used are usually metallic. One of the most widely used materials for the same is Titanium-based alloy like Ti-6Al-4V, which suffers difficulty processing and machining due to its thermo-physical properties. The thermo-physical property of the material plays a significant role in the biocompatibility and safety to use them as dental implants. Due to its hardness and difficult-to-machine characteristics, a large amount of heat gets generated while machining, creating dimensional error. Hence before assembly of parts, they must be processed so that stress deformation of the assembly due to heat can be avoided. During machining of Ti-6Al-4V, the cooling strategy needs prior information on the thermal field, and hence, the distribution of temperature in the material is an essential domain to study. To understand the thermal distribution in the material during machining, 3-dimensional heat diffusion equations have been solved using a Finite Difference scheme coupled with the Liebmann method to generate the thermal distribution in the material. An efficient parallelized code for the same has been written in MATLAB and utilized in this numerical study. This study reveals the variation of the temperature gradient with time and space, all along with the three orthogonal directions, which will be helpful for the scientists, engineers, and surgeons to ascertain the sustainability [1, 2], suitability, and longevity of the implants.


2021 ◽  
Author(s):  
R. A. Rytov ◽  
V. A. Bautin ◽  
N. A. Usov

Abstract A linear combination of spherically symmetric heat sources is shown to provide optimal stationary thermal distribution in magnetic hyperthermia. Furthermore, such spatial location of heat sources produces suitable temperature distribution in biological medium even for assemblies of magnetic nanoparticles with a moderate value of specific absorption rate (SAR), of the order of 100 - 150 W/g. We also demonstrate the advantage of using assemblies of magnetic nanocapsules consisting of metallic iron nanoparticles covered with non magnetic shells of sufficient thickness in magnetic hyperthermia. Based on numerical simulation we optimize the size and geometric structure of biocompatible capsules in order to minimize the influence of strong magneto-dipole interaction between closely spaced nanoparticles. It is shown that assembly of capsules can provide sufficiently high SAR values of the order of 250 - 400 W/g at moderate amplitudes H0·= 50 - 100 Oe and frequencies f = 100 - 200 kHz of alternating magnetic field, being appropriate for application in clinics.


Micromachines ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1223
Author(s):  
Guangbao Shan ◽  
Guoliang Li ◽  
Dongdong Chen ◽  
Zifeng Yang ◽  
Di Li ◽  
...  

An accurate equivalent thermal model is proposed to calculate the equivalent thermal conductivity (ETC) of shield differential through-silicon via (SDTSV). The mathematical expressions of ETC in both horizontal and vertical directions are deduced by considering the anisotropy of SDTSV. The accuracy of the proposed model is verified by the finite element method (FEM), and the average errors of temperature along the X-axis, Y-axis, diagonal line, and vertical directions are 1.37%, 3.42%, 1.76%, and 0.40%, respectively. Compared with COMSOL, the proposed model greatly improves the computational efficiency. Moreover, the effects of different parameters on the thermal distribution of SDTSV are also investigated. The thermal conductivity is decreased with the increase in thickness of SiO2. With the increase in pitch, the maximum temperature of SDTSV increases very slowly when β = 0°, and decreases very slowly when β = 90°. The proposed model can be used to accurately and quickly describe the thermal distribution of SDTSV, which has a great prospect in the design of 3D IC.


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