Misorientation Characteristics at the Growth Front of Abnormally-Growing Goss Grains in Fe–3%Si Steel

Tae‑Young Kim,Tae‑Wook Na,Hyung‑Seok Shim,Yong‑Keun Ahn,Yong‑Kwon Jeong,Heung Nam Han,Nong‑Moon Hwang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

Penetrating morphologies at the growth front of abnormally-growing Goss grains in Fe–3%Si steel was examined in view ofthe possibility that they are the two-dimensional section of the solid-state wetting (SSW) along the triple junction line. Toobtain the statistically meaningful data, 102 penetrated grain and 204 penetrating abnormally-growing Goss grain morphologieswere examined. The misorientation angles of penetrating and penetrated grains were measured by electron backscattereddiffraction. Among the 102 examined penetrated grain boundaries, none has low misorientation angles less than 15°,whereas 17.2% of the 204 penetrating grain boundaries have low misorientation angles, and 23.5% of them have coincidencesite lattice boundaries. Besides, boundary energies of penetrating Goss grains, which were estimated from misorientationangles of the three grains in the penetrating morphology, satisfied the energetic condition for SSW along the triple junctionline. These results imply that the abnormal grain growth of Goss grains in Fe–3%Si steel occurs by the mechanism of subboundaryenhanced SSW.

Elevated extracellular calcium ions promote proliferation and migration of mesenchymal stem cells via increasing osteopontin expression

Lee, Mi Nam,Hwang, Hee-Su,Oh, Sin-Hye,Roshanzadeh, Amir,Kim, Jung-Woo,Song, Ju Han,Kim, Eung-Sam,Koh, Jeong-Tae Nature Publishing Group UK 2018 Experimental and molecular medicine Vol.50 No.11

<▼1><P>Supplementation of mesenchymal stem cells (MSCs) at sites of bone resorption is required for bone homeostasis because of the non-proliferation and short lifespan properties of the osteoblasts. Calcium ions (Ca<SUP>2+</SUP>) are released from the bone surfaces during osteoclast-mediated bone resorption. However, how elevated extracellular Ca<SUP>2+</SUP> concentrations would alter MSCs behavior in the proximal sites of bone resorption is largely unknown. In this study, we investigated the effect of extracellular Ca<SUP>2+</SUP> on MSCs phenotype depending on Ca<SUP>2+</SUP> concentrations. We found that the elevated extracellular Ca<SUP>2+</SUP> promoted cell proliferation and matrix mineralization of MSCs. In addition, MSCs induced the expression and secretion of osteopontin (OPN), which enhanced MSCs migration under the elevated extracellular Ca<SUP>2+</SUP> conditions. We developed in vitro osteoclast-mediated bone resorption conditions using mouse calvaria bone slices and demonstrated Ca<SUP>2+</SUP> is released from bone resorption surfaces. We also showed that the MSCs phenotype, including cell proliferation and migration, changed when the cells were treated with a bone resorption-conditioned medium. These findings suggest that the dynamic changes in Ca<SUP>2+</SUP> concentrations in the microenvironments of bone remodeling surfaces modulate MSCs phenotype and thereby contribute to bone regeneration.</P></▼1><▼2><P><B>Bone formation: released calcium could stimulate stem cells</B></P><P>Studies with mouse cells and bone samples indicate how calcium ions released during the normal turnover of bone promote the supplementation of stem cells needed to make new bone during routine “remodeling” and regeneration after injury. Our bones are degraded and remodeled continuously, requiring the controlled supplement of stem cells that create bone-forming cells called osteoblasts. Jeong-Tae Koh and colleagues at Chonnam National University, Gwangju, South Korea, exposed the relevant stem cells to increased concentrations of external calcium ions. This promoted cell proliferation and migration that allow the cells to support new bone formation. The research suggests this effect on stem cells may be achieved by calcium ions released directly from bone as it is naturally degraded. The findings may help researchers develop new ways to encourage bone regeneration after injury and surgery.</P></▼2>

나트륨-수증기 반응에 대한 실험적 연구

정지영,정경채,김병호,김태준,최종현,박남국 한국공업화학회 2002 응용화학 Vol.6 No.2

An experimental study for the investigation of the sodium-steam reaction phenomena was carried out. No significant aggressive explosion phenomena were observed as compared with that of sodium-water reactions. It was also observed that the rate of increase of reaction temperature decreases with increasing initial temperature of liquid sodium and that the temperature of the target depends upon the flow rate of injected steam.

대용섬유자원으로써 어저귀를 이용한 한지제조(제1보) : 어저귀의 건물 생산량 및 펄프화 특성 Productivity and Pulping Characteristics of Indian Mallow

정선화,조남석,최태호 한국목재공학회 2002 목재공학 Vol.30 No.2

본 실험은 산림자원의 감소 예방과 지구의 환경보존을 위해서 생장이 빠르고 펄프원자재로 활용할 수 있는 비목재 섬유작물을 도입하는 것을 목적으로 하고 있다. 또한 부족한 한지의 원료인 닥나무를 수입하고 있는 실정에서, 국내에서 자생하고 있는 비목재섬유로 한지를 제조함으로써 수입대체 및 원가절감 등 일석이조의 효과를 거둘 수 있다. 이에 불량한 환경조건에서도 생육이 왕성한 어저귀(Abutilon avicennae G.)를 재배하여 그간의 진보된 펄프 제조기술을 적용하여 새로운 제지용 원료로 개발함으로써 부족한 원자재는 물론이거니와 국내 부존자원 이용의 극대화를 꾀하고자 실시하였다. 또한 폐기처리되는 농산물의 이용극대화를 꾀하기 위해 전목펄프화를 실시하였다. 그 결과 어저귀는 생장속도가 빠르고 수확기가 짧으며 집약적 재배 및 관리가 가능하여 단위면적당 최대의 수확량을 올릴 수 있었다. 어저귀 인피부의 섬유장은 2.4㎜로써 목재섬유 중 소나무와, 비목재섬유 중 케나프와 매우 유사한 결과를 보여주었고, 화학성분의 분석결과 어저귀 섬유는 추출성분의 함량이 높고 리그닌이 적은 것이 특징적으로 나타났다. 펄프화와 관련하여 인피부는 150℃에서 48∼57%, 전간부는 170℃에서 43∼51%의 높은 수율을 나타냈고, 설포메틸 펄프화법의 수율이 더 높게 나타났다. 펄프의 탈리그닌율도 두가지 펄프화법 모두 90% 이상의 높은 탈리그닌율을 나타내었다. Indian mallow is characterized by the rapid growth and high harvest of the fibrous materials. This study was carried out to investigate the sheet properties of Hanji using Indian mallow, made by different pulping methods, such as alkali and sulfomethylated pulpings and different stock compositions, various mixing ratios of bast fiber, woody core and whole stalk fibers. The results from this study were summarized as follows. The length and width of the bast fibers were 1.40∼4.30㎜(av. 2.35㎜) and 9.2∼26.4㎛(av. 18.3㎛), respectively. The cell wall thickness was 4.0∼11.5㎛(av. 7.7㎛). Runkel ratio, flexibility coefficient and fiber length/fiber width ratio were 1.38, 0.42 and 128 respectively. Bast fiber and whole stalk were cooked by alkali and sulfomethylated methods. Sulfomethylated pulping resulted in superior pulp in terms of yield and quality as compared with those of alkali pulping. The pulp yields of bast fiber was higher than those of whole stalk.

一部 大學生의 B型肝炎 感染에 關한 疫學的 調査硏究

南貞祐,廉容泰,洪두루미 고려대학교 의과대학 1986 고려대 의대 잡지 Vol.23 No.1

Modern serologic techniques for the detection of HBsAg and Anti-HBs, particularly radioimmunoassay(R1A) and enzyme immunoassay(EIA), provided a technical foundation for more precise and sophisticated epidemiologic studies, of hepatitis B infection. Through a many study it has been revealed that the prevention and the control of hepatitis B infection have emerged as an urgent and serious problem in Korea. However, there are still some arguments on the prevalence rate, mode of transmission, control measures and so on, which hinder the development of certain countermeasures at national level. The authors have conducted this study on a total of 4,125 freshmen of 1983 academic year in Korea University to analyse the prevalence of HBsAg and Anti-HBs positives detected by RPHA and PHA methods in relation to a variety of factors such as socio-demographic, vaccination, family history, personal hygiene, past history of liver diseases and etc. The findings of the study were as follows; 1. Positive rates of HBsAg and Anti-HBs were 7.0 and 19.3% respectively. The rate for male was slightly higher than that of female. 2. In detecting HBsAg, sensitivity of RPHA against RIA method was 91.4% and specificity was 100% whereas sensitivity of PHA method was 51.9% and specificity was 88.9% respectively in detecting Anti-HBs. A question of false negative patient was raised in detecting Anti-HBs by PHA method. 3. Only two percent of HBsAg positive students were found to be acute hepatitis patients as a results of liver function test and 10% of them were thought to be in chronic state. 4. Among Anti-HBs Eegatives, the turn-out rate to positive after three times of vaccination with one of H-B-Vax and Hepavax were 61.0% by PHA method. But it was revealed to be 87.8% after reexamination of Anti-HBs negatives by the method of RIA. 5. The relationship of personal characteristics of subjects with the positive rate of HBsAg and Anti-HBs was analyzed. The communities with small population showed higher rates than ones with large population. For example, Cheju has shown the highest rate and was followed by Cholla Puk-Do and Kangwon-Do. In addition, the results suggested that the appearance of HBsAg and Anti-HBs associated with past history of liver diseases and family history of liver diseases, especially mother's past history. 6. Other factors including housing, past history of vaccination, skin test, acupuncture, behavior such as sharing tooth brush or razor with others and etc., have been reviewed but .there was no significant association with hepatitis B infection.

석재 제품 생산 시스템을 위한 Fieldbus 기술

남부희,이철민,장태정,이재환 강원대학교 석재복합신소재제품연구센터 1997 석재연 논문집 Vol.2 No.-

본 연구에서는 생산 시스템에서의 통신을 위한 Fieldbus의 한 종류인 Profibus의 프로토콜을 소프트웨어적으로 구현하였다. 그리고 Profibus를 이용한 생산 시스템에서의 네트웍 구성을 위해 인터페이스 카드와 Stand-alone 보드를 설계하였다. 인터페이스 카드는 PC를 Profibus 시스템의 마스터 스테이션으로 사용할 수 있도록 설계되었으며, Stand-alone 보드는 슬레이브 스테이션으로 설계되었다. 또한 간단한 DC 모터 위치제어 플랜트를 제작하여 Profibus 프로토콜을 구현한 소프트웨어 및 하드웨어의 성능을 확인하였다. In this research, we have implemented the protocol of Profibus, a kind of Fieldbus for communication in manufacturing systems, as a software. We also have designed an interface card and a stand-alone Board to use in constructing networks for manufacturing systems. The interface card was designed to make the PC be a master station of a Profibus system and the stand-alone board was designed as a slave station. A DC motor position control system was made to test the performance and the effectiveness of the S/W and the H/W.

호텔 식음료 시설의 중요 요인에 따른 호텔 선택 영향 연구

남태석,정연국 문화관광연구학회 1999 문화관광연구 Vol.1 No.2

형질전환 제초제저항성 벼 밀양 204호의 농업적 특성

정응기,이기환,원용재,박향미,전남수,최준호,구연충,한창덕,은무영,김태산,남민희 Plant molecular biology and biotechnology research 2005 Plant molecular biology and biotechnology research Vol.2005 No.

This study was conducted to investigated the major characteristics of genetically modified rice of "Milyang 204" originated from Dongjinbyeo compared to a non-transgenic rice varieties Dongjinbyeo and Junambyeo. Basta resistant transgenic rice lines carrying bar gene produced by the Yeongnam Agricultural Research Institute were evaluated for their agronomic characters. The transgenic Japonica rice of "Milyang 204" showed inferior phenotypic traits compared to a non-transgenic rice variety Dongjinbyeo and Junambyeo. On the basis of UPOV (Union Internationale Pour la Protaection des Obtentions Vegetables) and NSMO(National Seed Management Office) the transgenic "Milyang 204" showed difference in some traits out of some agronomic traits, such as leaf color, angle of flag leaf, number of spikelets, culm length, white core and white belly compared to the nontransgenic varieties rice.

대용섬유자원으로써 어저귀를 이용한 한지제조 (제2보) : 인피 및 목질부 섬유를 이용한 한지 제조 Manufacturing of The Hanjis Made from Bast Fiber and woody core fibers

정선화,조남석,최태호 한국목재공학회 2004 목재공학 Vol.32 No.1

생장속도가 빨라서 단위면적당 Biomass의 생산량이 많은 어저귀(Indian mallow, Abutilon avicennae G.)를 원료로 하여 펄프화하였으며, 제조한 한지의 물리적·기계적·현미경적 특성에 관하여 비교 검토하였다. 제조한 한지의 특성을 살펴보면 광학적, 강도적 현미경적인 특성에서 설포메틸 펄프화법이 우수한 결과를 나타냈고, 장섬유인 인피부 펄프에 대한 단섬유인 목질부 펄프의 혼입량 증가에 따른 변화에 있어 지질(밀도, 백색도, 불투명도, 지합)의 변화는 점차 증가했으나, 강도는 감소하는 경향을 나타냈다. This study was carried out to investigate the sheet properties of Indian mallow Hanji, made by different pulping methods, such as alkali and sulfomethylated pulpings, and different stock compositions, various mixing ratios of bast fiber and woody core fibers. Indian mallow hanjis made from the sulfomethylated pulps had higher brightness and sheet strength than the alkali pulps. It was found that the brightness of sulfomethylated pulp was enough high without an extra-bleaching. In the mechanical properties of Indian mallow hanjis mixed with bast fiber and woody core stalk pulps, the sheet strength were decreased as wood core pulps contents were increased. The sheet formation were increased as the increase of woody core pulps contents, while the sheet strength decreased Although the sulfomethylated pulping resulted in higher pulp yield, no morphological differences of fiber surfaces were shown as compared to the different pulping methods.

국제회의 참가자의 국제회의 기획업에 대한 만족도 조사에 관한 연구

남태석,정연국,최정은 한국관광정책학회 2000 觀光政策學硏究 Vol.6 No.3

Conventions have become extremely important in today's business world. Every fields has its conventions : Professions, trade unionism, education, arts, commerce, politics, and fraternalism all rely on conventions to bring together the membership's cross section of ideas. At past sutudies, there were few detailed studied for the PCO services in Korea even though they have taken several accesses to the international convention in the hardware aspect like facilities as well as in the software aspect. Whereas, for the activation of the international convention industry, this study shows how much the participant are satisfied with the service of the PCO, and then presents the way out of tough conditions of Korean tourism as holding more international convention, which invites quality foreign tourists in large number. Therefore the object of this study shall be of help to the desirable development of international convention industry through the survey of the satisfaction with the PCO service based on the positive investigation and the view of attendant. In a common view of domestic and foreign people, while Korean PCO comes up to the standard in the planning and working out the international convention, it cannot meet the various requirements of attendants in the specialized knowledge interpretation and relationship. Therefore it needs the new establishment of the developend and systmatic departure to bring up the specialized PCO.