Secondary Recrystallization in Metals: Approach by Solid-State Wetting Hyung-Seok Shim and Nong-Moon Hwang

( Hyung Seok Shim ),( Nong Moon Hwang ) 대한금속재료학회(구 대한금속학회) 2014 대한금속·재료학회지 Vol.52 No.9

The mystery of Goss selective abnormal grain growth (AGG) in Fe-3%Si steel has long remained unsolved since its discovery by Goss in 1933. Similarly, the mechanism of secondary recrystallization, which is commonly observed in many metallic systems, has long been a puzzle. Here, attempts to solve this puzzle are reviewed with a focus on solid-state wetting along the triple junction of polycrystalline metals. Especially, the grains with sub-boundaries of very low energy exclusively have a high probability to grow by solid-state wetting and as a result can grow abnormally. The 3-dimensional Monte Carlo (MC) and phase field model (PFM) computer simulations showed that the presence of sub-boundaries induces AGG. The existence of sub-boundaries exclusively in abnormally-growing grains was experimentally confirmed in Fe-3%Si steel and in 5052 Al alloy. The time evolution of abnormally growing grains by ex-situ observation and electron backscattered diffraction (EBSD) analysis of 5052 Al alloy clearly revealed many microstructural evidences for AGG by triple-junction wetting. Misorientation angle measurements by EBSD of the grains belonging to the penetrating morphology showed that the penetrated grain boundaries have high energy and the penetrating grain boundaries tend to have low energy, in agreement with the wetting condition along the triple junction. Parallel three-dimensional MC simulations starting with the experimental misorientationdata, which consider sub-boundaries and precipitates, show many realistic AGG features observed experimentally. (Received July 28, 2013)

Organic Solar Cells: Solution‐Processable Reduced Graphene Oxide as a Novel Alternative to PEDOT:PSS Hole Transport Layers for Highly Efficient and Stable Polymer Solar Cells (Adv. Mater. 42/2011)

Yun, Jin‐,Mun,Yeo, Jun‐,Seok,Kim, Juhwan,Jeong, Hyung‐,Gu,Kim, Dong‐,Yu,Noh, Yong‐,Jin,Kim, Seok‐,Soon,Ku, Bon‐,Cheol,Na, Seok‐,In WILEY‐VCH Verlag 2011 Advanced Materials Vol.23 No.42

<P>Solution‐processable reduced graphene oxide as a hole‐transporting layer for highly efficient and stable organic solar cells is reported on page 4923 by Dong‐Yu Kim, Seok‐In Na, and co‐workers. Introduction of a newly reduced graphene oxide by simple solution processing into solar cells dramatically raises the cell efficiency and cell life‐time. The results will allow full use of chemically reduced graphene and will advance the realization of carbon‐based printable optoelectronic devices. </P>

Bisphosphonates의 이독성에 관한 연구

박일석,김형종,임현준 대한이비인후과학회 1998 대한이비인후과학회지 두경부외과학 Vol.41 No.3

HPLC-MS/MS를 이용하여 혈장 중 레보티인정의 정량분석

채석,오형근,이상선,김형기,손동렬,염윤기,맹주양,권준택 순천향의학연구소 2008 Journal of Soonchunhyang Medical Science Vol.14 No.2

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Human Chorionic Gonadotropin(HCG)에 의한 넙치, Paralichthys olivaceus의 배정효과

박인석,김형배,최희정,이영돈,손진기 제주대학교 해양연구소 1992 해양자원연구소연구보고 Vol.16 No.-

For the evaluation of hormonal control of sperm in cultured fish a method to quantify the spermiation response of mature flatfish to hormonal therapy is described. Spermatocrit was determined after 30 min. in centrifuge condition of 12,000rpm. Sperm density was estimated by a standard hemacytometer method. However, sperm density can be predicted from spermatocrit since their relationship is linear as described by the re-gression equation. Y=1.14X-0.04 (r=0.91. P<0.0001. n=50), where Y is spermatocrit and X is sperm density. Sperm density levels ranged from 21.5 to 98.4×10^(4) spermatozoa per ㎕ milt corresponding to spermatocrit values of 12 to 95%. Milt production by mature flatfish was highest (7.4ml per kg body weight) at 24h after injection of 1,000IU of human chorionic gonadotropin(HCG) per kg body weight and coincided with low spermatocrit (63%) and sperm density (67.4×10^(4) spermatozoa per ㎕ milt) levels. No significant differences was appeared in milt production, spermatocrit and sperm density between control and HCG-treated fish at 48h after HCG injection. These results demonstrate that spermiation in mature flatfish can be reliably evaluated by a spermatocrit method and that HCG is effective in stimulating of spermiation in this species.

都市내 文化財 周邊地域 建築物의 色彩計劃에 관한 硏究 : 水原城廓 周邊建築物을 對象으로

최형석 수원대학교 1994 地域社會開發 Vol.6 No.-

Suweon City needs redevelopment of old downtown around Suweon Castle and redevelopment seems to make new landscapes. When considering the preservation of historic landscapes including Suweon Castle, it is very important that new buildings which will be constructed during redevelopment will have to be in harmony with historic iandscapes in various aspects, and especially the colors of buildings adjacent to historic landscapes can have a great effect on visual harmony. Therefore, to improve the effect of preseravtion through color planning, this study aims to survey the present colors of buildings around Suweon Castle, investigate the degree of harmony between Suweon Castle and buildings in color with aesthetic measure method of Moon & Spencer's and suggest the harmonious colors which have possibility to harmonize with Suweon Castle. The results are as follows ; 1. Most Buildings were found to harmonize with Suweon Castle, but in the case of buildings being viewd against granite of voussouir, they were in disharmony or low degree of aesthetic. 2. As a result of examining the degree of harmony between Suweon Castle and the 8, N 8.5, N 9, 10YR 2/1, 7.5YR 2/1, 2.5Y 2/1 ext. have little difficulties in use for buildings around Suweon Castle( especially, Paldal Gate and Jangahn Gate ). 3. As the more colors are included in calculating degree of aesthetic, the upper the degree of harmony becomes, the height regulation by angle of elevation seems to take more effects than the existing absolute height regulation in increasing the degree of harmony and compensating the private wipeouts caused by regulations.

상부 조기 위암 환자의 복강경하 상부 위절제술 3례 경험

조규석,김형철,박경규,이문수,송옥평,임철완,신웅진,주종우,유기원 순천향의학연구소;Soonchunhyang Medical Research Institute 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Background : The reported incidence of early gastric cancer located in the upper portion of the stomach has been increasing with the recent advances in its diagnosis and screening. Recently, we have successfully performed laparoscopic assisted proximal gastrectomy and gastric tube reconstruction without pyloroplasty on three patients with early gastric carcinoma localized to the upper third of the stomach. We describe our modification of this procedure in this report. Method : After creating an surgical pneumoperitoneum, the stomach was mobilized using laparoscopic coagulating shears. Upper half of the greater curvature and three-quarters of the lesser curvature were then dissected along with regoinal D2 lymphadenectomy. This was followed by a 5 cm, longitudinal mini-laparotomy in the upper abdomen, and the construction of the exteriorized stomach with a gastric tube measuring 20 cm long and 4 cm wide. Reconstruction with an esophagogastrostomy was performed using a circular stapler. Result : No post-operative morbidity or mortality was observed in this small series of patients. The average operative time was 250 minutes (range 220-300 minutes), and the average blood loss was 150 ml (range 90-180 ml). The mean number of lymph nodes harvested during these laparoscopic proximal gastrectomies was 24 nodes (range 22-25 lymph nodes). The average postoperative hospital stays was 7.5 days (range 7-8 days). Conclusion : Our technique of laparoscopic assisted proximal gastrectomy and gastric tube reconstruction without phloroplasty offers a minimally invasive technique with the potential of impoving the post-operative quality of life patients with an early-stage proximal gastric cancer.

주의력 결핍 과잉행동장애 아동의 평가를 위한 정지신호 과제의 적용

시현석,이종범,박형배,사공정규,송창진,배진우 大韓神經精神醫學會 2000 신경정신의학 Vol.39 No.1

연구목적 및 방법 : ADHD환아에 있어 뇌의 전두엽의 기능인 실행기능 중 특히 억제기능을 가장 잘 측정하는 것으로 알려진 정지신호과제를 사용하여 실제로 정지신호를 ADHD환아에게 적용하였을 때 정상 아동과 비교하였을 때 ADHD의 전두엽의 실행기능 중 억제 기능의 이상을 실질적으로 반영하는 검사인지, 증상의 정도와 수행결과는 어떤 연관성을 보이는지, 현재 가장 널리 사용되고 있는 연속수행 검사와는 어떤 차이를 보이는지, 과잉행동의 유무와 수행의 연관성은 어떠한지 그리고 부가적으로 정지신호과제의 ADHD진단에 있어서의 판별력은 어느 정도인지를 알아보기 위해 본 연구를 시행하였다. 전두엽의 기능을 반영하는지와 임상에서의 유용성을 알아보기 위해 ADHD군 40명과 대조군 18명을 대상으로 연구하여 다음과 같은 결과를 얻었다. 결 과 : 대조군과 ADHD군의 비교에서는 정지신호과제의 수행 성적은 상대적 종결속도의 Z점수(ZRFT)와 블록당 평균 지연시간(mean delay×block), 그리고 일차 반응시간(primary-RT)에 있어서 유의한 차이가 있는 것으로 나타났다(p<0.05), ADHD군과 대조군의 연속수행검사(CPT)의 수행에 있어 유의한 차이가 나는 변인은 없었다. 또한 두 검사간의 상관성에 있어서는 정지신호반응시간(SSRT)와 CPT의 정반응시간이 그리고 primary-RT와 일차반응시간의 표준 편차(primary-SD)가 CPT의 민감도와 정반응시간과 상관성이 있는 것으로 나타났다(p<0.05). 정지신호과제 수행과 한국형 주의력결핍 장애 평가 척도 - 가정판(ADDES-HV)과의 상관도에서는 유의한 상관성을 나타낸 것은 없었다. 나이와 지능에 따른 정지신호과제의 경향분석에서 유의하게 경향성을 나타낸 것은 지에 따른 차이에서는 primary-SD였으며 나이에 따른 차이에서는 SSRT였다(p<0.05). 여기에서 지능과 primary-SD와의 관계는 지능이 증가함에 따라 감소하다 어느 정도에서 더 이상 감소하지 않았으며, 나이와 정지신호반응시간과의 관계는 나이가 증가함에 따라 반응시간이 짧아지다가 어느 정도에서 더 이상 감소하지 않는 추세를 보였다. 정지신호과제의 판별력 검증에서 mean delay×block과 primary-RT가 가장 높은 판별력(각각 75%)을 나타냈으며 그 외 억제율(P-inhibit)은 63.89%, SSRT는 58%, ZRFT는 67%, primary-SD는 58%의 판별력을 보였다. ADDH 환아를 대상으로 과잉행동이 있는 군과 없는 군으로 나누어 수행의 정도를 비교하였다. 여기에서는 두 군 사이에 유의한 차이가 있는 변인은 없었다. 결 론 : 이러한 결과로 볼 때 정지신호과제가 국내에서 사용된다면 향후 임상에서의 ADHD의 선별검사로서 뿐만 아니라 연구에 있어서도 기여하는 바가 크다고 생각된다. Objectives and Methods : The purpose of this study was to examine availabilities of stop-signal task as a screening test for ADHD and as a research tool. Stop-signal task was applied to 40 ADHD patients and 18 normal children. Followings are the results of this study. Results : There were significant differences between ADHD group and control group in ZRFT, mean delay×block and primary-RT of stop-signal task performance(p<0.05). There was no significant difference in results of continuous performance test. SSRT of stop-signal task had significant correlation with hit reaction time of continuous performance test, and primary-RT and primary-SD with attentiveness and hit reaction time of continuous performance test. There was no significant correlation between scores of ADDES-HV and stop-signal task performance. In change of primary-SD according to intelligence, primary-SD decreased as intelligence increased but made plateau after IQ 110, and in change of SSRT according to age, SSRT decreased as intelligence increased but made plateau after 10 year-old. In discriminant ability, mean delay×block and primary-RT showed highest discriminant ability(each 75%). In addition P-inhibit showed 63.89%, SSRT showed 58%, ZRFT showed 67%, and primary-SD showed 58% in discriminant ability. There was no significant difference in stop-signal task performance between ADHD with hyperactivity and ADHD without hyperactivity. Conclusions : In this point of view, stop-signal task was proved to be useful research tool for attention deficit hyperactivity disorder as well as useful screening test tool.

한국 엘리트스포츠 발달의 정치적 배경에 관한 연구 : 60년대부터 80년대까지 from 60s to 80s

송형석,김홍식 師範大學 體育硏究所 1997 서울大學校 體育硏究所論集 Vol.18 No.2

The purpose of this study was to investigate the political affect to Korean elite sport was developed dramatically along the Korean modern age, in 60s, 70s, and 80s. To proceed this, I presumed that the dramatic development of Korean elite sport was caused by polical intention in large part. And under this I tried to give the various example sourses supporting this preposition. The relationship between politic and sport is said that sport is used as polical means. It means that although politic and sport is under interacting process, politic have major power on sport. If this is true, what polical intention is imposed on sport? First, politic use sport as symbolic propaganda effect. In fact, if a national team made a briliant record in international game of if a government held a international game such as Olympic or world cup game and finished successfully, this fact could make better image about the country which affect the international hierachy. Secondly, sport is used as means to bind people. Under Park Jung hui government, sport was used as this effect by a series of policies and laws such as National Sport Promotion Law in 1962.

유한요소법을 이용한 수직형 롤러 분쇄기용 테이블 라이너의 내구 해석에 관한 연구

최형모,이경영,조석수,이선봉 三陟大學校 産業科學技術硏究所 2002 産業科學技術硏究論文集 Vol.7 No.1

Vertical roller mill, which perform the grinding and parting blending of raw material, is the one of the important machine to produce ordinary portland cement. The table liner belonged to the vertical roller is mill the one of the main parts influencing its grinding efficiency. The life of table liner is estimatede to 4×107cycles in the design stage, but at the field, when its operating time reaches to 4×106 ~ 8×106 cycles, the fracture of table liner being to be found. The fracture of table liner commences from the outside edge of grinding path contacting with the grinding roller. Its maintenance normally take 30% of the total maintenance costs of the roller mill. Therefore, this study shows the clarification of the reasons occuring the fatal destruction of the table liner by fatigue fracture analysis utilizing fracture mechanics and by FEM using ANSYS 5.6.