• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.11
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• pp.1549-1554
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• 2000

A new method to determine the total heat exchange factor was proposed for the prediction of billet temperature in a reheating furnace. This method employed the squared of the difference between measured and predicted temperatures as an objective function. The real billet temperature in a walking beam type reheating furnace with 19.75m of its effective length was directly measured by thermocouples. The present method was validated by showing that the predicted billet temperature was in a good agreement with the measured one.

• Journal of Korean Society for Atmospheric Environment
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• v.5 no.1
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• pp.52-61
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• 1989

The hydrodenitrogenation of quinoline dissolved in n-heptane was studied over sulfided Ni-Mo/$\gamma-Al_2O_3$ catalyst at the range of the temperature between 553 K and 673 and the total pressure between $20 \times 10^5$ Pa and $60 \times 10^5$ Pa in a fixed bed flow reactor. Quinoline conversion was very high at relatively low temperature and total pressure, and decreased with quinoline partial pressure. The thermodynamic equilibrium between quinoline and Py-THQ existed in wide ranges of experimental conditions and shifted in favor of quinoline at higher temperature. At the range of the temperature betwwen 553 K and 673 K and at the total pressure $60 \times 10^5$ Pa, the quinoline reaction rate was 1st order with respect to the concentr4ation of quinoline and its apparent activation energy was 7.15 Kcal/mole.

• Proceedings of the ESK Conference
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• 1997.10a
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• pp.72-96
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• 1997

To investigate the difference of sweating reaction on somato types. We measured total sweat rate, locl sweat rate, skin temperature, physiological reactions and psyschological reactions at $25{\pm}1^{\circ}C$ and $25{\pm}1^{\circ}C$ under laboratory conditions. Nine healthy adult females were divided into three somato types (slender(3), normal(3) and obese type(3)). The results were as follows; Total sweat rate was highest in obese type, and then comes normal type and slender type in order. Local sweat rate was highest in infrascapular area, and then breast, the back of the hand, upperarm, ant. leg, and ant. thigh in order in all somato types. Mean skin temperature was highest in slender type, and then normal type and obese type in order. Rectal temperature, blood pressure and pulse rate were highest in boese type. Psychological reactions were appeared 'hot' 'humid' 'sweat' as ambient temperature go up. And somato types make little difference in psychological reactions.

• Journal of the Ergonomics Society of Korea
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• v.17 no.2
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• pp.65-82
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• 1998

To investigate the difference of sweating reaction by the somato types, we measured total sweat rate, local sweat rate, skin temperature, physiological reaction and psychological reaction at $25{\pm}1^{\circ}C$ and $29{\pm}1^{\circ}C$ under laboratory conditons. Nine healthy adult females were divided into three somato types : slender (3), normal (3) and obese (3). The results were as follows ; Total sweat rate was highest in the obese type, followed by the normal and slender types in order. Local sweat rate was highest in the infrascapular area, and then came breast, the back of the hand, upper ann, anterior leg, and anterior thigh in all somato types. Mean skin temperature was highest in the slender type, and followed the normal and obese types. Rectal temperature, blood pressure and pulse rate were highest in the obese type. Psychological reaction appeared 'hot', 'humid', 'sweaty' as ambient temperature went up. Somato types made little difference in psychological reaction.

• Structural Engineering and Mechanics
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• v.67 no.4
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• pp.337-346
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• 2018

The purpose of this study is to investigate thermal post-buckling analysis of a laminated composite beam subjected under uniform temperature rising with temperature dependent physical properties. The beam is pinned at both ends and immovable ends. Under temperature rising, thermal buckling and post-buckling phenomena occurs with immovable ends of the beam. In the nonlinear kinematic model of the post-buckling problem, total Lagrangian approach is used in conjunction with the Timoshenko beam theory. Also, material properties of the laminated composite beam are temperature dependent: that is the coefficients of the governing equations are not constant. In the solution of the nonlinear problem, incremental displacement-based finite element method is used with Newton-Raphson iteration method. The effects of the fibber orientation angles, the stacking sequence of laminates and temperature rising on the post-buckling deflections, configurations and critical buckling temperatures of the composite laminated beam are illustrated and discussed in the numerical results. Also, the differences between temperature dependent and independent physical properties are investigated for post-buckling responses of laminated composite beams.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.4_1
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• pp.411-419
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• 2021

In this study, IGBT_Total_Loss and DIODE_Total_Loss were used to analyze the slope of the junction temperature for each section for temperature and duty variables in order to simply calculate the junction temperature of the power semiconductor (IGBT). As a result of the calculation, IGBT_Max_Junction_Temp and DIODE_Max_Junction_Temp form a proportional relationship with temperature for each duty. This simulation data shows that the power loss of a power semiconductor is calculated in a complex manner according to the current dependence index, voltage dependence index, and temperature coefficient. By applying the slope for each condition and section, the junction temperature of the power semiconductor can be calculated simply.

• Food Science of Animal Resources
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• v.33 no.4
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• pp.439-447
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• 2013

Time-temperature integrators (TTIs) are simple and cost-efficient tools which may be used to predict food quality. Enzymatic TTIs are devised to indicate food quality in the form of color alterations from green to red, based on the cumulative impacts of temperature and time period on the enzymatic reactions. In this study, the quality of ground beef patties was investigated for the parameters of pH levels, color, VBN, water holding capacity, and total microbial counts, depending on various storage temperatures (5, 15, and $25^{\circ}C$). TTIs were attached to the surface of the ground beef patties in order to evaluate the degree of correlating colorimetric changes with the determined quality parameters. Through the Arrhenius equation, activation energy and constant reaction rates of TTI, VBN, and total microbial counts were calculated as to observe the relationship between enzymatic reactions of the TTI and food spoilage reactions of the ground beef patties. VBN and total microbial counts were already increased to reach decomposition index (VBN: 20, total microbial count: 7-8 Log CFU/g) of meat at middle stage of storage period for each storage temperature. Although activation energy of TTI enzymatic reactions and food spoilage reactions of the ground beef patties were similar, the change of TTI color was not a coincidence for food spoilage at $5^{\circ}C$ and $15^{\circ}C$ of storage temperature. It was suggested that TTI should be designed individually for storage temperature, time, type of meat, or decomposition index of meat.

• Coupled systems mechanics
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• v.6 no.4
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• pp.399-415
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• 2017

This paper deals with the nonlinear static deflections of functionally graded (FG) porous under thermal effect. Material properties vary in both position-dependent and temperature-dependent. The considered nonlinear problem is solved by using Total Lagrangian finite element method within two-dimensional (2-D) continuum model in the Newton-Raphson iteration method. In numerical examples, the effects of material distribution, porosity parameters, temperature rising on the nonlinear large deflections of FG beams are presented and discussed with porosity effects. Also, the effects of the different porosity models on the FG beams are investigated in temperature rising.

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.675-680
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• 2009

This article describes NO emission characteristics in SM coal combustion. Combustion experiments was performed in the method of increasing temperature after feeding coal and feeding coal after increasing temperature. NOx emission is in inverse proportion to combustion temperature at the fuel rich condition and it was caused by conversion fuel N to $N_{2}$ at the strong reduction condition. In addition, feeding gas flow rate increased as total fuel NOx increase by conversion of fuel N to NO at the oxidation condition. It could be separated in total fuel-N, volatile-N, char-N to NO according to analysis of total fuel NO emission from char combustion at each temperature. In the result, almost total NOx emission was caused by volatile-N in SM-coal.

• Korean Journal of Medicinal Crop Science
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• v.19 no.4
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• pp.271-275
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• 2011

In this study, ginseng flower water extracts were analyzed to set up the ginsenoside content and quality optimization condition. The highest total ginsenoside content among the ginseng flower water extracts was 67.44mg/g which was extracted at $85^{\circ}C$ for 3 hours. In addition, the ginsenoside content decreased according to the increased extraction temperature and time. The highest total content of $Rb_2$ and Re was 37.42mg/g at $75^{\circ}C$ for 6 hours. Total content of $Rb_2$ and Re decreased according to the increased extraction temperature and time. The highest prosapogenin ($Rg_2$ + $Rg_3$ + $Rh_1$) content among the total of ginseng flower water extracts was 18.58mg/g which was extracted at $95^{\circ}C$ for 12 hours. The sweetness, absorbance were increased according to the increased extraction temperature and time. But pH was decreased according to the increased extraction time.