MgCl₂溶液內에서 STS 304 HP Stainless Steel 熔接部의 破壞擧動에 對한 硏究

金永奭,丁太權,朴昌彦,洪錫柱,梁仁榮,金基玉,朴煥奎,李茂錫,曺圭宰,鄭在康 조선대학교 생산기술연구소 1983 生産技術硏究 Vol.1983 No.-

This paper is based on an experiment analysing the stress corrosion cracking behaviour of welding specimens compared to that of non-welding specimens of STS 304 HP stainless steel in corrosion solution. As a corrosion condition, stainless steel has been known to be the most fragile in a solution of 42% MgCl₂heated to the boiling point, therefore the experiment was carried out in this condition. The experiment was carried out with argon gas TIG welding specimens and non-welding ones made of stainless steel plates, thickness 2mm, by tensile force. At this time, the tensile force was taken to be the value of the yield strength of the tensile test specimens divided by the safety factor of 3.0 to 3.5, 4.0, 4.5, and 5.0. In this paper, the relations between Time of Initial Crack, Time of Failure, Time of Final Fracture and Crack Propagation Length were investigated and then plotted. Furthermore, the relations between Stress Intensity Factor K proposed by Irwin and the Time of Initial Crack, the Time of Failure, the Time of Final Fracture were calculated and plotted. At the last, all the relations plotted were expressed to normal equations by computer, and the equations were used to analyse the data obtained in the experiment. The conclusions obtained in this study are as follows: 1. Welding materials, compared with non-welding ones, as the Time of Initial Crack, the Time of Failure, and the Time of Final Fracture were generally very fast, appeared to be a phenomenon of unstable brittleness fracture. 2. Non-welding materials, compared with welding ones, as the safety factor was larger or the working stress was smaller, appeared to be a phenomenon that the longer had had greater durability. Therefor, welding materials must be considered enough to be used in heate affected and stress corrosion atmosphere. 3. The normal equations of the Time of Initial Crack and the variation rate to the same Stress Intensity Factor K are as follows: (A) Non-welding T =259702.4-5451.2 K+28.386 K² T = -5451.2+28.386 K (B) Welding T= -332.693+28.043 K-0.211 K² T' =28.043-0.211 K here, T; Time of Initial Crack, T'; Variation Rate of Time of Initial Crack to Stress Intensity Factor K, K ; Stress Intensity Factor.

저압 MOCVD 방법으로 성장된 lnAlAs 에피층에서 상분리와 규칙 현상의 관찰

조형균(Hyung Koun Cho),이번(Bun Lee),백종협(Jong-Hyeob Baek),한원석(Won Seok Han),이정용(Jeong Yong Lee),권명석(Myoung Seok Kwon) 한국진공학회(ASCT) 1999 Applied Science and Convergence Technology Vol.8 No.3(2)

LP-MOCVD 방법에 의해 InP 기판 위에 성장된 InAlAs 에피층의 상분리와 규칙 현상을 DCXRD, PL, TEM을 이용하여 분석하였다. DCXRD와 PL의 반측폭과 강도로부터 InAlAs 에피층의 구조적, 광학적 품질이 성장 온도가 증가함에 따라 향상되었다. 상분리와 규칙 현상으로 인한 밴드갭의 감소량은 565℃, 615℃, 700℃의 성장 온도에서 각각 291, 246, 28 meV이고 구조적, 광학적 품질과 같은 경향성을 보여주었다. TEM으로부터 상분리 현상은 565℃의 성장 온도에서 가장 강하게 관찰되었고, HRTEM 이미지 사진에서 InAs가 풍부한 영역과 AlAs가 풍부한 영역 사이에 조성 차이로 인하여 약 2˚의 격자 줄무늬의 회전이 발생하였다. 565℃에서 성장된 시편에 대한 RTA 열처리 실험은 880℃에서 3분간의 열처리로 약 78 meV 정도의 밴드갭 증가를 보여주고, TEM을 통해 밴드갭의 증가는 규칙 현상의 완전한 사라짐이라는 것이 관찰되었다. 이 결과는 열처리 전에 발생한 밴드갭 감소량의 3/4가 상분리 현상으로 발생하였다는 결론을 얻을 수 있다. We have studied the phase separation and ordering phenomenon of lnAlAs epilayers grown on InP substrate by LP-MOCVD with DCXRD, PL, and TEM. From the intensity and FWHM of DCXRD and PL, we observed that the structural and optical quality of lnAlAs epilayers were improved as growth temperature increased. The band-gap reduction due to phase separation and ordering is 291, 246, and 28 meV in the InAlAs epilayers grown at 565℃, 615℃, and 700℃, respectively, and shows the same trends as structural and optical quality. The maximum degree of phase separation was obtained by TEM from the lnAlAs epilayer grown at 565℃ in which the HRTEM micrograph showed the lattice fringe between lnAs-rich and AlAs-rich regions was tilted by 2˚ due to composition difference. However, the maximum degree of ordering by intensity of extra spots was obtained at the medium growth temperature. The annealing experiment by RTA of sample grown at 565℃ shows a maximum band-gap shift of 78 meV at 880℃ for 3 min, and TEM shows that the origin of the blue shift of band-gap is the complete disappearance of ordering. Through annealing we can conclude that short time annealing affects only ordering and that most of the total band-gap reduction (~3/4) occurs by phase separation.

Doxylamine 중독 후 발생한 횡문근융해증 4예

유종훈,이정석,이동윤,이철호,이준상,홍수희,최의혁,서보정,권형주,이무열,박영우 대한신장학회 1999 Kidney Research and Clinical Practice Vol.18 No.3

Doxylamine is common over-the-counter sleep preparations & frequently involved in overdoses. The clinical course is dominated by the anticholinergic effects, including central nervous system & autonomic effects. We report 4 cases of suicide attempts in adults where ingestion of the doxylamines were complicated by rhabdomyolysis. They ingested doxylamines variable amount & were carried to emergency department. They complained gastrointestinal or central nervous system symptoms. Gastric lavages & administrations of activated charcoal were done. Creatine phosphok inase levels were normal or markedly elevated on arrival, but peaked several days later. Serum creatinine levels were normal. 99mTc-MDP bone scans were showed increased muscle labelling at the regions of muscle injury. They were treated with hydration, urine alkalinization, & supportive measures in hospital. On considering cause of rhabdomyolysis, our patients did not show any evidence of viral illness or coingestion of other potential myopathic toxins to support a secondary cause of rhabdomyolysis. The mechanism of rhabdomyolysis in cases of doxylamine overdose seems to be a direct toxic effect of the drug on striated muscle, but the exact mechanism is not clear. In all cases where such overdoses are suspected, consideration should be given to obtaining a urinalysis & a creatine phosphokinase level on arrival & creatine phosphokinase levels are carefully followed. Primary detoxication included gastric lavage & administration of activated charcoal. The patient's urine output & renal function should be closely monitored.

Solution to shunt defects in solution-processed CIGSSe solar modules

Seung Hoon Lee,Min Kyu Kim,Soohyun Bae,Byoung Koun Min,Yoonmook Kang,Hae-Seok Lee,Donghwan Kim 한국진공학회 2020 한국진공학회 학술발표회초록집 Vol.2020 No.2

불안장애 환자를 대상으로 한 한국판 상태불안척도의 요인분석

이건석,배활립,김대호,Lee, Koun-Seok,Bae, Hwal-Lip,Kim, Dae-Ho 대한불안의학회 2008 대한불안의학회지 Vol.4 No.2

Objective : Brief screening for anxiety symptoms in clinical practice can further facilitate the diagnosis and evaluation of anxiety disorders. This study examined the factorial validity of the Korean version of the State-Trait Inventory (STAI)-Form X, one of the most frequently used self-report questionnaires for anxiety. Methods : Data from the STAI and Beck Depression Inventory were obtained from a consecutive sample of 200 outpatients diagnosed with DSM-IV anxiety disorders at a psychiatric unit of a university hospital. The factor structures of the State and Trait Scales were assessed using exploratory factor analysis. Results : Three-factor components, including 'State anxiety present', 'State anxiety absent' and 'Selfconfidence', were extracted from the State Scale, explaining 59% of the total variance. A four-factor solution involving 'Trait anxiety and depression present', 'Trait anxiety and depression absent', 'Anxiety proneness' and 'Stability' (59% of total variance) was extracted from the Trait Scale. The internal consistency of the STAI and factors were satisfactory. There were significant correlations between depressive symptoms and factors of the STAI. Conclusion : The STAI-form X showed factorial validity for Korean patients with anxiety disorders. However, our finding that this anxiety scale also measures depressive symptoms should be interpreted with caution.

이공계 연구활동 종사자들에서 기질 및 성격과 직무스트레스의 관련성

박환진(Hwanjin Park),이건석(Koun-Seok Lee),최윤범(Yoonbum Choi),박경은(Kyungeun Park),이수진(Soo-Jin Lee),송재철(Jaechul Song) 대한직업환경의학회 2012 대한직업환경의학회지 Vol.24 No.2

Transcriptome analysis of the zebrafish mind bomb mutant

Hwang, Junmo,Kim, Hyung-Soo,Seok, Ji-Woong,Kim, Jun-Dae,Koun, Soonil,Park, So-Young,Lee, Jinseok,Kim, Hyang Sook,Kim, Hyung-Seok,Kim, Kil Soo,Chang, Kyu-Tae,Ryoo, Zae Young,Wang, San Ming,Huh, Tae-Lin Springer-Verlag 2009 Molecular genetics and genomics Vol.281 No.1

한국어판 벡 우울 설문지 2판의 신뢰도 및 요인분석 : 대학생을 대상으로

유병관,이혜경,이건석,Yu, Byeong-Kwan,Lee, Hye-Kyung,Lee, Koun-Seok 대한생물정신의학회 2011 생물정신의학 Vol.18 No.3

Objectives The Beck Depression Inventory (BDI) is one of the most widely used self-report measures of depression in both research and clinical practice. The Beck Depression Inventory Second Edition (BDI-II) is the most recent version of the BDI. Validity of the BDI-II has been documented in other countries. This study examined the factor structure of the Korean version of BDI-II in a large sample of university students. Method Data were obtained from 2,529 students of Kongju National University. The factor structures of the Korean version of BDI-II were assessed using exploratory and confirmatory factor analysis. Results A high level of internal consistency and reliability (Cronbach's ${\alpha}$ = 0.91) and item homogeneity was confirmed. Exploratory factor analysis showed a two-factor structure (cognitive and somatic-affective), which was almost identical to the original model demonstrated by Beck et al. The following confirmatory factor analysis also supported the two-factor structure (cognitive and somatic-affective) is a better fit than the other two-factor structure (cognitive-affective and somatic). The higher mean score for women compared to men is consistent with the results of previous reports. Conclusion These data support the reliability and concurrent validity of the Korean version of BDI-II as a measure of depressive symptoms in nonclinical samples.

저압 MOCVD 방법으로 성장된 InAlAs 에피층에서 상분리와 규칙 현상의 관찰

조형균,이번,백종협,한원석,이정용,권명석,Cho, Hyung-Koun,Lee, Bun,Baek, Jong-hyeob,Han, Won-Seok,Lee, Jeong-Yong,Kwon, Myoung-Seok 한국진공학회 1999 Applied Science and Convergence Technology Vol.8 No.3(2)

We have studied the phase separation and ordering phenomeon of InAlAs epilayers grown on InP substrate by LP-MOCVD with DCXRD, PL, and TEM. From the intensity and FWHM of DCXRD and PL, we observed that the structural and optical quality of InAlAs epilayers were improved as growth temperature increased. The band-gap reduction due to phase separation and ordering is 291, 246, and 28 meV in the InAlAs epilayers grown at $565^{\circ}C$, $615^{\circ}C$, and $700^{\circ}C$, respectively, and shows the same from the InAlAs epilayer town at 5$65^{\circ}C$ in which the HRTEM micrograph showed the lattice fringe between InAs-rich and AlAs-rich regions was tilted by $2^{\circ}$ due to composition difference. However the maximum degree of ordering by intensity of extra spots was obtained at medium growth temperature. The annealing experiment by RTA of sample grown at $565^{\circ}$ shows a maximum band-gap shift of 78eV at $880^{\circ}$ for 3 min, and TEM shows that the origin of the blue shift of band-gap is the complete disappearance of ordering. Through annealing we can conclude that short time annealing affects only ordering and that most of the total band-gap reduction (~3/4) occurs by phase separation.

Mediating Effect of Internet Addiction on the Association between Resilience and Depression among Korean University Students: A Structural Equation Modeling Approach

Kwok Kei Mak,Jae seung Jeong,Hye-Kyung Lee,Koun seok Lee 대한신경정신의학회 2018 PSYCHIATRY INVESTIGATION Vol.15 No.10

Objective: This study examined the mediating role of internet addiction in the association between psychological resilience and depressive symptoms. Methods: 837 Korean university students completed a survey with items of demographic information, Connor-Davidson Resilience Scale (CD-RISC), Internet Addiction Test (IAT), and Patient Health Questionnaire (PHQ-9) in 2015. The complex associations among psychological resilience, internet addiction, and depressive symptoms were delineated using structural equation models. Results: In the most parsimonious model, the total effect and indirect effect of resilience on depressive symptoms via internet addiction, were statistically significant. The goodness of fit of the measurement model was satisfactory with fit indices, normed fit index (NFI) of 0.990, non-normed fit index (NNFI) of 0.997, comparative fit index (CFI) of 0.998, root mean square error (RMSEA) of 0.018 (90%CI=0.001–0.034); and Akaike Information Criterion (AIC) of -21.049. Conclusion: The association between psychological resilience and depressive symptoms was mediated by internet addiction in Korean university students. Enhancement of resilience programs could help prevent internet addiction and reduce the related depression risks.