• Journal of The Korean Astronomical Society
• /
• v.17 no.2
• /
• pp.104-114
• /
• 1984

The effective temperatures, $T_{eff}$ (flux) of 52 early type stars are derived from de-reddened monochromatic and integrated fluxes obtained by absolute spectrophotometry, using the method of graphical analysis pioneered by Blackwell and Shallis (1977), similar to that of Underhill (1982) and Tobin (1983). We also estimated the effective temperatures, $T_{eff}$ (comp) of the same stars by comparing their de-reddened energy distributions with those of the LTE model atmospheres by Kurucz (1979). The effective temperatures derived from these two methods are found to be in good agreement, confirming that they are effective for the estimation of effective temperatures of early type stars.

• 한국연소학회:학술대회논문집
• /
• 2006.10a
• /
• pp.110-116
• /
• 2006

A new measurement technique based on a two-color pyrometry and modulated LII signals to measure local soot particle temperatures has been proposed and examined experimentally. The theoretical review suggests that modulated LII signals of soot particles is suitable for a two-color pyrometry as long as the temperature increase due to laser heating remains relatively small. The modulated LII signals from ethylene and propylene diffusion flames were simultaneously measured at 550 and 750 nm by a dual measurement system that consists of optical fibers, PMT and lock-in amps. The local soot particle temperatures of diffusion flames could be obtained using a two-color pyrometry and modulated LII signal based new technique.

• Journal of Environmental Health Sciences
• /
• v.27 no.1
• /
• pp.69-74
• /
• 2001

A study on temperature control of freezers & refrigerators in department stores and supermakets was conducted in Taegu are from July 15 through August 30 in order to determine how the temperature is effectively controled for food safety. Five departments and four supermarkets were selected randomly and fifty seven refrigerators and fifty nine freezers were inspected to observe temperature of thermometers and measure the temperature of the coolers by laser thermometer. The results are as follow; 1. Out of one hundred and sixteen coolers, eighty six (74.1%) were open type coolers and thirty (25.9%) were closed types (p<.05). 2. Twenty five (89.3%) of refrigerators and twenty three (82.1%) of freezers in department stores had thermometers and twenty seven refrigerators (93.1%) and twenty two (71%) of freezers in supermarkets had thermometers respectively (p<.01). 3. The measured temperatures of coolers increased in the afternoon to compared to the temperatures of them in the morning time (p<.01). The difference of temperatures of coolers between department stores and supermarkets was wider in the supermarkets and difference of temperatures of food items between refrigerators and freezers was wider in the refrigerators but the difference was not statistically significant. 4. The temperatures of forty four (84.6%) out of fifty two refrigerators within recommended ranges and those of forty two (93.3%) of forty five freezers higher than recommended ranges (p<.05).

• Coupled systems mechanics
• /
• v.8 no.3
• /
• pp.219-245
• /
• 2019

The present research deals in two dimensional (2D) transversely isotropic magneto generalized thermoelastic solid without energy dissipation and with two temperatures due to time harmonic sources in Lord-Shulman (LS) theory of thermoelasticity. The Fourier transform has been used to find the solution of the problem. The displacement components, stress components and conductive temperature distribution with the horizontal distance are calculated in transformed domain and further calculated in the physical domain numerically. The effect of two temperature are depicted graphically on the resulting quantities.

• Structural Engineering and Mechanics
• /
• v.51 no.2
• /
• pp.199-214
• /
• 2014

The present investigation is concerned with the effect of two temperatures on functionally graded (FG) nanobeams subjected to sinusoidal pulse heating sources. Material properties of the nanobeam are assumed to be graded in the thickness direction according to a novel exponential distribution law in terms of the volume fractions of the metal and ceramic constituents. The upper surface of the FG nanobeam is fully ceramic whereas the lower surface is fully metal. The generalized two-temperature nonlocal theory of thermoelasticity in the context of Lord and Shulman's (LS) model is used to solve this problem. The governing equations are solved in the Laplace transformation domain. The inversion of the Laplace transformation is computed numerically using a method based on Fourier series expansion technique. Some comparisons have been shown to estimate the effects of the nonlocal parameter, the temperature discrepancy and the pulse width of the sinusoidal pulse. Additional results across the thickness of the nanobeam are presented graphically.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.27 no.9
• /
• pp.1499-1507
• /
• 2003

Physical importance of cutting temperatures has long been recognized. Cutting temperatures have strongly influenced both the tool life and the metallurgical state of machined surfaces. Temperatures in drilling processes are particularly important, because chips remain in contact with the tool for a relatively long time in a hole. Tool temperatures tend to be higher in drilling processes than in other in machining processes. This paper concerns with modeling of thermal behaviors in drilling processes as well as estimation of the cutting temperature distribution based on remote temperature measurements. One- and two-dimensional estimation problems are proposed to analyze drilling temperatures. The proposed thermal models are compared with solutions of finite element methods. Observer algorithms are developed to solve inverse heat conduction problems. In order to apply the estimation of cutting temperatures, approximation methods are proposed by using the solution of the finite element method. In two-dimensional analysis, a moving heat source according to feedrate of the drilling process is regarded as a fixed heat source with respect to the drilling location. Simulation results confirm the application of the proposed methods.

• 한국연소학회:학술대회논문집
• /
• 1999.10a
• /
• pp.241-249
• /
• 1999

Soot particle temperatures in co-flow diffusion flames have been measured using a two-color pyrometry at the pressure of 0.2 MPa(2 atm). The measured soot particle temperatures along with the integrated soot volume fractions are analyzed to understand soot formation characteristics. At 0.2 MPa, the addition of small amount of air into ethylene do not change the soot particle temperature in soot formation regions. This result showed that the increase of soot formation with addition of air is mostly due to the chemical effect of the added air, such as the increased role of C3 chemistry during the early stage of soot inception process. The addition of sufficient air into ethylene, however, changes soot particle temperatures and the understanding of soot formation characteristics becomes complicated. Measured soot particle temperatures also showed that there is no significant temperature effect for the synergistic effect of ethylene/propane mixture on soot formation.

• Steel and Composite Structures
• /
• v.32 no.6
• /
• pp.779-793
• /
• 2019

The purpose of this research paper is to depict the thermomechanical interactions in transversely isotropic magneto thermoelastic solid with two temperatures and without energy dissipation in generalized LS theories of thermoelasticity. The Laplace and Fourier transform techniques have been used to find the solution of the problem. The displacement components, stress components, and conductive temperature distribution with the horizontal distance are computed in the transformed domain and further calculated in the physical domain numerically. The effect of two temperature and relaxation time are depicted graphically on the resulting quantities.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2003.11a
• /
• pp.47-51
• /
• 2003

In this paper, we compared the thermal environment in the livingroom with panel heating system of Korea and Japan. The houses are two apartments and two single houses in Korea, and two apartments in Japan. The outdoor temperatures, indoor air temperatures, surface temperatures on floor and humidities were measured. The survey to the residents and recording of operation were also collected. The results were as follows.1. The Korean houses are warmer and drier(approximately 23$^{\circ}$C, 38%) than those of Japan.(approximately 20$^{\circ}$C, 57%). And indoor temperaures of Korean apartment are stabie. 2.The residents in Japan put on and off the switches of the heating system frequently.

• Steel and Composite Structures
• /
• v.34 no.2
• /
• pp.309-319
• /
• 2020

The objective is to study the deformation in a homogeneous isotropic modified couple stress thermoelastic medium with mass diffusion and with two temperatures due to a thermal source and mechanical force. Laplace and Fourier transform techniques are applied to obtain the solutions of the governing equations. The displacements, stress components, conductive temperature, mass concentration and couple stress are obtained in the transformed domain. Numerical inversion technique has been used to obtain the solutions in the physical domain. Isothermal boundary and insulated boundaryconditions are used to investigate the problem. Some special cases of interest are also deduced.