• Bulletin of the Korean Chemical Society
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• v.1 no.1
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• pp.39-44
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• 1980

Activation energies for plastic deformation calculated from traditional phenomenological equations have been criticized frequently since the values are different by authors, and also by experimental conditions. The reasons of different activation enthalpies are clarified in this study. Our method for calculating activation enthalpies based on the authors' theory of plastic deformation was presented and discussed. The method was applied to various cases of alloys, the calculated activation enthalpies are listed and compared with the activation energies obtained by the traditional methods in order to show the reasonableness of our method. The physical meaning of the activation enthalpies which we found was clarified.

• Physical Therapy Rehabilitation Science
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• v.10 no.3
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• pp.304-310
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• 2021

Objective: This study aimed to investigate effective cueing methods for selective muscle activation of gluteus medius muscles. Design: Cross sectional study design. Methods: Using the inclusion criteria for this study, 20 healthy adults, both males and females were selected for the measurement of muscle activation of gluteus maximus, gluteus medius, and tensor fascia latae muscles while performing clamshell exercise, basic movements in leg raise in side-lying, and 3 different cueing methods. Electromyogram was used to measure muscle activation, and both muscle activation and muscle ratio were compared during the basic movements and different cueing methods. Results: Gluteus medius activation was highest using "try not to make your body rotate" (cueing method 2) in both clamshell exercise and leg raise side-lying (F=5.533, p<0.05, F=7.771, p<0.05), and muscle ratio was highest in clamshell exercise using cueing method 2 (p<0.05) and "don't move your tensor fascia late" (cueing method 1) in leg raise side-lying (p<0.05). This study showed that cueing method 1 in leg raise side-lying and cueing method 2 in clamshell exercise were the most effective cueing methods for selective muscle activation of gluteus medius muscle. Conclusions: The results of this study may be used as basic information for future studies on muscle activation and muscle ratio for different cueing methods and different muscles in various exercises.

• Fire Science and Engineering
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• v.33 no.1
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• pp.1-6
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• 2019

The activation energy of CPVC (Chlorinated Poly Vinyl Chloride) used for non-metallic synthetic resin piping in fire-fighting was measured by thermogravimetric analysis (TGA). The activation energy was determined using by TGA kinetic methods, such as Kissinger and Flynn-Wall-Ozawa method. The calculated activation energy was 128.07 kJ/mol (Kissinger method) and 145.60 kJ/mol (Flynn-Wall-Ozawa method). The difference in activation energies calculated by the Kissinger method and Flynn-Wall-Ozawa method was not considered to be significant considering that the different analysis methods. The combustion characteristics will be tested in a future study through an evaluation of thermal deterioration using an accelerated deterioration and air oven aging test and the lifetime of CPVC will be predicted.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.7 s.172
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• pp.200-207
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• 2005

This study compares two different methods of measuring brain-BOLD activation. By comparing two different methods of measurement i.e., one method calculating the neural activation area (the number of activated voxels), while the other measured the neural activation intensity (the mean intensity of selected activated yokels), this study identified the more precise method of measuring brain activation which results from the completion of a visuospatial task. 16 right-handed male college students (mean age 23.2 years) participated in this study as subjects. Functional brain images were scanned on them using a 3T MRI single-shot EPI method. No correlation was found between the levels of cognitive performance and number of activated yokels in the activated brain areas. However, a significant correlation was found between the levels of cognitive performance and the mean intensity of selected activated yokels in the parietal, frontal, and other areas. In conclusion, the method of mean intensity was considered a better index of brain activity rather than the activated yokels measurement method.

• Journal of Energy Engineering
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• v.13 no.2
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• pp.166-172
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• 2004

The activated carbon was produced from Sancheong bamboo by steam and carbon dioxide gas activation methods. The carbonization of raw material was conducted at 90$0^{\circ}C$ and gas activation reactions were conducted with respect to various conditions. -activation temperature 750-90$0^{\circ}C$, the flow rate of steam 0.5-2g-$H_2O$/g-char$.$hr, the flow rate of carbon dioxide 5-30$m\ell$-$CO_2$/g-char-min and activation time 1-5 hr. The prepared activated carbons were measured yield, the adsorption capacity of iodine and methylene blue, BET specific surface area and pore size distribution. The adsorption capacity of iodine (680.5-1526.1 mg/g) and methylene blue (18.3-221.5 mg/g) increased with creasing activation temperature and activation time. The adsorption capacity of iodine and methylene blue increased with the activation gas quantity in the range of 0.5-1.5g-$H_2O$/g-charㆍhr, 5-18.9$m\ell$-Co$_2$/g-charㆍmin. But those decreased over those range due to the pore shrinkage. The steam activation method was superior in efficiency to carbon dioxide activation method.

• Transactions on Electrical and Electronic Materials
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• v.15 no.2
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• pp.81-86
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• 2014

The process parameter in optimized KOH alkali activation of soft carbon series coke material in high purity was set with DOE experiments design. The activated carbon was produced by performing the activation process based on the set process parameters. The specific surface area was measured and pore size was analyzed by $N_2$ absorption method for the produced activated carbon. The surface functional group was analyzed by Boehm method and metal impurities were analyzed by XRF method. The specific surface area was increased over 2,000 $m^2/g$ as the mixing ratio of activation agent increased. The micro pores in $5{\sim}15{\AA}$ and surface functional group under 0.4 meq/g were obtained. The contents of the metal impurity in activated carbon which is the factor for reducing the electrochemical characteristics was reduced less than 100 ppm through the cleansing process optimization. The electrochemical characteristics of activated carbon in 38.5 F/g and 26.6 F/cc were checked through the impedance measuring with cyclic voltammetry scan rate in 50~300 mV/s and frequency in 10 mHz ~100 kHz. The activated carbon was made in the optimized activation process conditions of activation time in 40 minutes, mixing ratio of activation agent in 4.5 : 1.0 and heat treatment temperature over $650^{\circ}C$.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.352-357
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• 2012

Techniques of thermal analyses such as DSC and TGA have been used in the study of activation energy (Ea) and frequency factor (A) depending on the particle size of RDX and HMX. Activation energy and frequency factor were calculated by Kissinger's method and Vyazovkin's method. As the particle size of RDX increased, TGA showed activation energy increased, but DSC didn't show. However, In case of HMX, as the particle size increased, both of DSC and TGA showed increase in activation energy. Moreover, Vyazovkin's method can obtain activation energy and mechanism according to decomposition of RDX and HMX.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.3
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• pp.193-200
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• 1989

The errors of activation energy calculated by the initial rise method from the characteristics of thermally stimulated current have been estimated and an equation for the correction of the error is proposed. The coefficients needed in the proposed equation are determined by the numerical method. It is shown that the activation energy calculated by the conventional initial rise method contains errors of 0.7-10% depending on the location of the data points of the interval on which the method is applied. However, the error can be reduced to less than 0.5% when corrected by using the proposed equation. It is finally concluded that the activation energy determined by the initial rise method can approach the true value by adapting the proposed error correction method which is effective and reliable.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10d
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• pp.661-663
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• 2002

객체 지향 분산 시스템에서 어느 한 객체가 메모리를 차지하게 되면 그 객체를 Active 하다고 하며 그 반대를 Passive 하다고 말한다. Activation 이란 Passive 한 객체를 Active 하게 해주는 전환 과정을 뜻한다. 자바의 RMI(Remote Method Invocation)는 Activation 메커니즘을 JDK1.2.x 버전부터 채택해 사용하고 있는데, Activation 메커니즘이 지원되지 않는 JDK1.1.X의 RMI 에 Activation 메커니즘을 덧붙이는 형태로 API를 제공하고 있기 때문에 그 뼈대는 Activation 메커니즘 기반이 아니므로 그 효율성 및 성능이 떨어진다 볼 수 있다. 본 논문은 이를 개선 Activation 메커니즘 기반의 API를 설계 구현한다.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_3
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• pp.1333-1339
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• 2023

To produce activated carbon fibers, the process is carried out through either physical activation method or chemical activation method. In this study, we present the results regarding the characteristics of activated carbon fibers manufactured under various conditions through the quantitative control of steam. The yield after activation indicates a decreasing trend with the increase in steam quantity and activation time. Additionally, specific surface area characteristics exhibit variations based on activation time and steam flow rate. The SEM analysis results reveal that higher steam flow rates lead to the presence of both mesopores and macropores on the surface of activated carbon fibers (ACF).