• 한국자기학회지
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• 제23권6호
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• pp.188-192
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• 2013

수직 자기기록 매체로 알려진 CoPt 자성막을 전기도금법으로 제작하여 자기상호작용이 활성화 부피와 면적에 미치는 영향을 조사하였다. 모든 시료의 상호작용 기구는 쌍극자 상호작용이었으며, 낮은 전류밀도에서 제작한 시료일수록 두께가 두꺼울수록 상호작용 세기가 증가하였다. 한편 활성화 부피는 낮은 전류밀도에서 제작한 시료가 더 컸으나 두께에 따른 증감현상은 뚜렷하지 않았다. 그러나 활성화 면적은 상호작용의 세기가 강할수록 전류밀도가 낮을수록 감소하는 경향을 보였다.

• Journal of the Korean Wood Science and Technology
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• 제19권4호
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• pp.18-26
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• 1991

This study was carried out to examine not only the effect and the process of activation of aluminum sulfate for the manufacture of PB and MDF, but also application of the activation treatment to PB and MOF made with MDI adhesive. The results were as follows: 1. For the manufacture of PB, activating effect did not take place Because the low moisture content of 30% in the process of activation treatment made probably insufficient activation. It needs to examine higher moisture content for the uniform and enough activation same as that of MOF. 2. In the case of MOF, Activating effect was excellent, it showed not only better results of MOR 48%, MOE 29%, IB 60% than those of the control but also better dimensional stability. 3. Application of alum activation to the PB and MDF made with MDI adhesive yielded no effects. Maybe it was the reson that the curing mechanism of MDI is different. 4. Modifing the wood surface was the oxidation and wettability was not the variable limiting glueline performance. It is necessary to make a more study about activating reaction.

• 생물정신의학
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• 제29권1호
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• pp.1-8
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• 2022

Objectives In regard to the social competition hypothesis, depression is viewed as an involuntary defeat strategy. A previous study has demonstrated that adaptation in microenvironments can result in a wide range of behavioural patterns including defense activation disorders. Using a simulation model with evolutionary ecological agents, we explore how the fitness of various defence activation traits has changed over time in different environments with high and low social mobility. Methods The Evolutionary Ecological Model of Defence Activation Disorder, which is based on the Marginal Value Theorem, was used to examine changes in relative fitness for individuals with defensive activation disorders after adjusting for social mobility. Results Our study examined the effects of social mobility on fitness by varying the d-values, a measure of depression in the model. With a decline in social mobility, the level of fitness of individuals with high levels of defense activation decreased. We gained insight into the evolutionary influence of varying levels of social mobility on individuals' degrees of depression. In the context of a highly stratified society, the results support a mismatch hypothesis which states that high levels of defence are detrimental. Conclusions Despite the fact that niche specialization in habitats composed of multiple microenvironments can result in diverse levels of defensive activation being evolutionary strategies for stability, decreased social mobility may lead to a decrease in fitness of individuals with highly activated defence modules. There may be a reason behind the epidemic of depression in modern society.

• 한국신뢰성학회지:신뢰성응용연구
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• 제13권2호
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• pp.117-127
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• 2013

In this paper, we studied the correlation between the activation energy($E_a$) of the raw materials and the structural characteristics of the White LED PKGs. The samples used in the study were composed of low power LED 3type and high power LED 5type. To calculate the activation energy($E_a$) of the White LED PKGs conducted three conditions of high temperature operation test based on the Arrhenius model. The number of samples used in the experiment is 10, respectively. The $T_j$ of Conditions and target specifics expressed $T_{j1}$, $T_{j2}$, $T_{j3}$. The activation energy ($E_a$) of the samples was calculated based on the value of the actually measured lifetime. We investigated the correlation between the activation energy ($E_a$) of the raw materials and the structural characteristics of the White LED PKGs. As a result, White LED PKGs activation energy($E_a$) value was confirmed that the material properties affected more than the structural characteristics of the LED PKGs and we found that activation energy of each LED Model has difference. Normally, The activation energy of phosphor of YAG type was indicated from 0.21 to 0.25[eV] and Silicate type was indicated from 0.12 to 0.16[eV]. According to the results, we confirmed that the activation energy of phosphor of YAG type is higher more than The activation energy of phosphor of Silicate type.

• 한국전문물리치료학회지
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• 제10권3호
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• pp.17-27
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• 2003

Repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability beyond the duration of the rTMS trains themselves. Depending on rTMS parameters, a lasting inhibition or facilitation of cortical excitability can be induced. Therefore, rTMS of high or low frequency over motor cortex may change certain aspects of motor learning performance and cortical activation. This study investigated the effect of high and low frequency subthreshold rTMS applied to the motor cortex on motor learning of sequential finger movements and brain activation using functional MRI (fMRI). Three healthy right-handed subjects (mean age 23.3) were enrolled. All subjects were trained with sequences of seven-digit rapid sequential finger movements, 30 minutes per day for 5 consecutive days using their left hand. 10 Hz (high frequency) and 1 Hz (low frequency) trains of rTMS with 80% of resting motor threshold and sham stimulation were applied for each subject during the period of motor learning. rTMS was delivered on the scalp over the right primary motor cortex using a figure-eight shaped coil and a Rapid(R) stimulator with two Booster Modules (Magstim Co. Ltd, UK). Functional MRI (fMRI) was performed on a 3T ISOL Forte scanner before and after training in all subjects (35 slices per one brain volume TR/TE = 3000/30 ms, Flip angle $60^{\circ}$, FOV 220 mm, $64{\times}64$ matrix, slice thickness 4 mm). Response time (RT) and target scores (TS) of sequential finger movements were monitored during the training period and fMRl scanning. All subjects showed decreased RT and increased TS which reflecting learning effects over the training session. The subject who received high frequency rTMS showed better performance in TS and RT than those of the subjects with low frequency or sham stimulation of rTMS. In fMRI, the subject who received high frequency rTMS showed increased activation of primary motor cortex, premotor, and medial cerebellar areas after the motor sequence learning after the training, but the subject with low frequency rTMS showed decreased activation in above areas. High frequency subthreshold rTMS on the motor cortex may facilitate the excitability of motor cortex and improve the performance of motor sequence learning in normal subject.

• 한국운동역학회지
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• 제18권4호
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• pp.115-124
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• 2008

본 연구는 만성 요통환자의 치료적 중재에서 체간 안정화 운동의 방법 중 매트 볼 운동군, 슬링 운동이 요통장애지수, 근력, 근활성도에 미치는 영향을 알아보기 위해 수행되었다. 각 중재 군들은 6주 동안 주 5회, 운동 프로그램을 실시하였으며, 대조군은 일반적 중재를 실시하여 다음과 같은 결론을 얻었다. 1. 요통장애지수는 중재 기간에 따라 매트 볼 운동군, 슬링 운동군에서 중재 기간이 증가됨에 따라 감소하여 통증과 장애정도가 효과적으로 감소하였다. 2. 근력은 매트 볼 운동군, 슬링 운동군은 모든 각도에서 중재 6주 후에 증가하여 효과적으로 증가하였다. 3. 근활성도는 복횡근은, 내복사글 복직근은 매트 볼 운동군, 슬링 운동군에서 근력이 증진됨에 따라 근활성도는 증가하였고, 외복사근은 매트 볼 운동군에서만 증가하였다. 본 연구를 결과를 종합해 보면 요통환자의 치료적 중재에서 체간 안정화 운동은 각 기간 별로 요통장애지수, 근력과 각 근육의 근활성도에서 효율적 영향을 미치며, 보다 많은 적용을 통하여 지속적인 연구가 이루어지기를 희망한다.

• Journal of Mechanical Science and Technology
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• 제20권8호
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• pp.1209-1216
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• 2006

An AZ31 magnesium alloy was tested at constant temperatures ranging from 423 to 473 K (0.46 to 0.51 Tm) under constant stresses. All of the creep curves exhibited two types depending on stress levels. At low stress (${\sigma}/ G < 4 {\times}10^{-3}$), the creep curve was typical of class A (Alloy type) behavior. However, at high stresses (${\sigma}/ G > 4 {\times}10^{-3}$), the creep curve was typical of class M (Metal type) behavior. At low stress level, the stress exponent for the steady-state creep rate was of 3.5 and the true activation energy for creep was 101 kJ/mole which is close to that for solute diffusion. It indicates that the dominant deformation mechanism was glide-controlled dislocation creep. At low stress level where n=3.5, the present results are in good agreement with the prediction of Fridel model.

• Korean Chemical Engineering Research
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• 제50권6호
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• pp.1086-1092
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• 2012

본 촉매가스화 실험에서 촉매로서 가치가 있는 천연광물과 순수촉매를 사용하여 저급석탄의 $CO_2$분위기하 활성화 에너지 및 생성된 합성가스의 성분을 분석하였다. 먼저 공업 분석과 원소 분석을 통해 6가지 저급석탄의 회분과 황 함유량을 측정하였다. 그 후 Thermogravimetric Analyzer (TGA)를 통해 저급석탄 열분해반응 특성을 고려하여 실험에 가장 적합한 저급석탄을 선정하였다. 선정된 삼화 저급석탄은 촉매와 섞어 $CO_2$분위기하 TGA실험을 진행하였으며, 결과를 토대로 Kissinger 방법을 이용한 활성화 에너지를 구하였다. 또한 shrinking core model을 이용해 활성화 에너지를 구하여 Kissinger 방법과 비교하였다. 그리고 반응기에서 이산화탄소 분위기하 생성된 합성가스는 Gas Chromatography (GC)를 이용하여 분석하였다. 가스를 분석한 결과 수소의 생성량은 $K_2CO_3$를 촉매로 사용하였을 경우 가장 크게 나타났으며, 앞서 구한 활성화 에너지 결과와 일치하는 경향을 나타내었다.

• Plant Biotechnology Reports
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• 제5권1호
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• pp.45-51
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• 2011

A low acid phosphatase 3 (lap3) mutant was identified and characterized from an Arabidopsis activation-tagged (Weigel) population. The roots of the lap3 plants showed lower acid phosphatase (APase) activity compared to wild-type ones under low-Pi conditions ($10{\mu}M\;Pi$). Plasmid rescue experiments revealed that the activation-tagging vector was inserted into the intergenic region between At4g31540 and At4g31550 in the Arabidopsis genome. The genotypic segregation of the lap3 mutation was tightly linked with the phenotypic segregation of root APase activity in the prgeny of lap3. The transcript level of the At4g31520 (SDA1: SEVERE DEPOLYMERIZATION OF ACTIN 1), located 7.4 kb from the CaMV 35S enhancers in the lap3 mutant, was significantly reduced compared to that in the wild type. It was speculated that cellular actin polymerization may be involved in Pi acquisition in higher plants.

• 감성과학
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• 제8권4호
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• pp.403-413
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• 2005

본 연구에서는 긍정 또는 부정 시각자극이 제시되었을 때, 행동활성화체계(Behavioral Activation System : BAS) 민감 집단과 행동억제 체계(Behavioral Inhibition System : BIS) 민감 집단 사이에 차이가 있는지를 살펴보았다. 실험은 8명씩의 BAS와 BIS 민감 성향을 가진 남자 대학생을 대상으로 이루어졌고, 안정 상태와 국제정서사진체계(International Affective Picture System)의 긍정/부정 사진자극이 제시되는 동안의 뇌파를 측정하였다. 뇌파의 분석은 뇌 신호원 국소화를 위해, 뇌파의 전기적 신호에 의하여 형성되는 전류밀도에 대한 3차원적인 접근방식으로 데이터를 처리하는 방법 중의 하나인 LORETA(Low-resolution electromagnetic tomography)를 사용하였다. 그 결과, 긍정자극제시의 경우, BAS 민감 집단이 BIS민감 집단에 비해 알파 대역에서 변연계에 포함되는 cingulate gyrus와 전전두엽이 더 활성화되는 반응을 보였다. 이는 BAS 민감집단이 BIS 민감집단에 비해 긍정자극에 대한 반응이 더 민감하고, BAS 또는 BIS라는 인간의 동기체계가 감성자극의 인지와도 관련이 있을 가능성을 시사한다.