• The Korean Journal of Financial Studies
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• v.12 no.1
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• pp.1-17
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• 2006

쇄신의 분산이 무한인 주가시계열이 장기의존성 과정에 의하여 생성되고 있는가 또는 생성되고 있지 않는가를 검정하고자 한다. 기존의 연구가 쇄신의 분산이 유한한 경우에 한정하여 장기의존성 주가 과정에 대한 장기기억성이 검토되어왔다. 이 논문에서는 쇄신의 분산이 유한한 경우와 무한한 경우에 다같이 적용되는 방법들을 한국종합주가지수의 일별수익률에 적용하여 장기기억 모수를 추정 검정한다. 추정방법으로서는 분수 가우스 잡음, 가우스 분수적분 자기회기 이동평균, 선형 분수안정잡음 등이 형성되는 상황에 절대값 방법, 분수 방법과 총량화 Whittle 방법을 사용한다. 한국종합주가지수의 일별대수수익률 시계열은 분산이 무한한 경우에도 장기의존성과정에 의하여 생성되고 있다. 극치가 존재해도 장기기억과정이 형성 되고 있다.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.06a
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• pp.133-137
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• 2000

구문태그가 부착되지 않은 코퍼스를 사용하여 문법규칙의 확률을 훈련하는 비통제 학습(unsupervised learning) 방법의 대표적인 것이 CNF(Chomsky Normal Form)의 CFG(Context Free Grammar)를 입력으로 하는 inside-outside 알고리즘이다. 본 연구에서는 의존문법을 CNF로 변환하는 기법에 대해 논하고 의존문법을 위해 변형된 inside-outside 알고리즘을 논한다. 또한 이 알고리즘을 사용하여 실제 훈련한 결과를 보이고, 의존규칙과 구문구조 확률을 같이 사용하는 hybrid방식 구문분석기에 적용한 결과를 보인다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.961-963
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• 2005

의존성 그래프는 컴파일러 최적화 분야에서 도입되어 유용하게 사용되고 있으며 프로그램 자르기(program slicing) 분야 등 활용가치를 높여가고 있는 프로그램 표현 방식이다. 우리는 실제적인 C 프로그램의 의존성 그래프를 생성하는 시스템을 구현하였으며 본 논문에서는 의존성 그래프의 개념과 구현과정을 설명한다.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.06a
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• pp.1-31
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• 1994

국내 에너지 수급여건 : 에너지소비증가율이 경제성장율을 상회하는 비효율적 에너지 소비구조가 지속 에너지의 불안정한 수급구조 장가화 추세 -세계 11위 에너지수입국, 세계2위 석유소비 증가세 시현('92) -에너지수입 의존도 : 95% 수준 -화석에너지 의존도 : 85% 상회 (OECD 평균 65% 수준) -고급에너지 수요의 상대적 고증가율 지속 (전력, 가스) -에너지수입액의 총 수입액중 비중증가 : '91년 15.1% $\to$ '93년 18.0%

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.241-243
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• 2001

이동 컴퓨팅 환경에서 이동 호스트의 위치가 변함에 따라 그 의미가 달라지는 위치 의존 질의를 효과적으로 처리하기 위해서는 이동 호스트의 캐시 기법이 중요하지만, 위치 의존 질의를 효과적으로 지원할 수 있는 지구국의 브로드캐스팅 기법도 중요하다. 본 논문에서는 지구국이 담당하는 영역을 격자로 나누어 인덱싱한 데이터를 위치 의존 질의에 적합하도록 공간-채움 곡선을 이용해서 선형 클러스터링하여 구성 시간을 줄이는 브로드캐스팅 기법을 제안하고, 구성 시간을 포함시킨 이동 호스트의 활동 시간을 측정하여 그 성능을 비교한다.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.478-486
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• 2020

The purpose of this study was to find out the actual status of smartphone students' dependence on college students, and to identify the correlation between depression, self-efficacy and smartphone overdependence, and the role of self-efficacy in the relationship between depression and smartphone overdependencee. The main results of the survey and analysis of 1,177 four-year college students located in Gyeonggi area are as follows. First, the percentage of college students' smartphone overdependence was very high at 34.1%. Second, there was a significant difference in prevalence of depression between the smartphone overdependence group(18.7%) and the general user group(11%). Third, self-efficacy showed a negative correlation with smartphone overdependence. The smartphone overdependence group showed significantly lower score in self-efficacy and self-regulation efficacy, confidence, and task difficulty preference than the general user group. Fourth, self-efficacy worked as a mediating variable in the relationship between depression and smartphone overdependence. In other words, the effect of depression on smartphone overdependence tended to decrease as self-efficacy rose in the relationship. Finally, we discussed the development of programs to support career and psychological counseling of university students.

• Progress in Medical Physics
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• v.17 no.2
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• pp.96-104
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• 2006

Experiments from several groups Including ours have demonstrated that $Ca^{2+}$ can enhance the inactivation of N-type calcium channels. However, it is not clear if this effect can be ascribed to a 'classic' $Ca^{2+}$-dependent inactivation (CDI) mechanism. One method that has been used to demonstrate CDI of L-type calcium channels is to alter the intracellular and extracellular concentration of $Ca^{2+}$. In this paper we replaced the external divalent cation to monovalent ion ($MA^+$) to test CDI. In the previous paper, we could separate fast (${\tau}{\sim}150ms$) and slow (${\tau}{\sim}2,500ms$) components of inactivation in both $Ba^{2+}$ and $Ca^{2+}$ using 5-sec voltage step. Lowering the external divalent cation concentration to zero abolished fast inactivation with relatively little effect on slow inactivation. Slow inactivation ${\tau}$ correspond very well with provided the $MA^+$ data is shifted 10 mV hyperpolarized and slow inactivation ${\tau}$ decreases with depolarization voltage in both $MA^+\;and\;Ba^{2+}$, which consistent with a classical voltage dependent inactivation (VDI) mechanism. These results combined with those of our previous paper lead us to hypothesize that external divalent cations are required to produce fast N-channel inactivation and this divalent cation-dependent inactivation is a different mechanism from classic CDI or VDI.

• Progress in Medical Physics
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• v.15 no.4
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• pp.215-219
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• 2004

Due to their excellence for the high-energy therapy range of photon beams, researchers show increasing interest in applying MOSFET dosimeters to low- and medium-energy applications. In this energy range, however, MOSFET dosimeter is complicated by the fact that the interaction probability of photons shows significant dependence on the atomic number, Z, due to photoelectric effect. The objective of this study is to develop a very detailed 3-dimensional Monte Carlo simulation model of a MOSFET dosimeter for radiological characterizations and calibrations. The sensitive volume of the High-Sensitivity MOSFET dosimeter is very thin (1 ${\mu}{\textrm}{m}$) and the standard MCNP tallies do not accurately determine absorbed dose to the sensitive volume. Therefore, we need to score the energy deposition directly from electrons. The developed model was then used to study various radiological characteristics of the MOSFET dosimeter. the energy dependence was quantified for the energy range 15 keV to 6 MeV; finding maximum dependence of 6.6 at about 40 keV. A commercial computer code, Sabrina, was used to read the particle track information from an MCNP simulation and count the tracks of simulated electrons. The MOSFET dosimeter estimated the calibration factor by 1.16 when the dosimeter was at 15 cm depth in tissue phantom for 662 keV incident photons. Our results showed that the MOSFET dosimeter estimated by 1.11 for 1.25 MeV photons for the same condition.

• The Korea Swine Journal
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• v.22 no.9 s.253
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• pp.160-161
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• 2000

• Korean Journal of Psychosomatic Medicine
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• v.12 no.1
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• pp.47-55
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• 2004

Objectives: The aim of this study was to investigate alexithymia, depressive symptoms, and stress response of patients with alcohol dependence. The results were taken as a basic data of ameliorating the quality of life. Methods: 94 patients with alcohol dependence completed stress response inventory, Korea depression scale, and toronto alexithymia scale successfully. Results: 55% of variance of alexithymia of patients with alcohol dependence were explained by the stress response and depressive symptoms and score of ADS, and the stress response had the most explanatory power. Conclusions: The alexithymia of patients with alcohol dependence may be influenced by depressive symptoms, education, frequency of drinking, and stress response. The specialists were identifying symptoms of depression and optimizing the management, therefore increasing the compliance and quality of life of patients with alcohol dependence.