Repetitive Compensation Control for AGC System By Using Pre-Pass Rolling Data

Hwan?Seong KIM,Jin?Seon PARK,Sang?Dol LEE,Keum?Jae LEE,Sung?Kwan PARK 제어로봇시스템학회 2001 제어로봇시스템학회 국제학술대회 논문집 Vol.2001 No.10

Effect of Strain Aging on Tensile Behavior and Properties of API X60, X70, and X80 Pipeline Steels

Sang‑In Lee,Seung‑Yong Lee,Seok Gyu Lee,Hwan Gyo Jung,Byoungchul Hwang 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.6

The effect of strain aging on tensile behavior and properties of API X60, X70, and X80 pipeline steels was investigated inthis study. The API X60, X70, and X80 pipeline steels were fabricated by varying alloying elements and thermomechanicalprocessing conditions. Although all the steels exhibited complex microstructure consisting of polygonal ferrite (PF), acicularferrite, granular bainite (GB), bainitic ferrite (BF), and secondary phases, they had different fractions of microstructuresdepending on the alloying elements and thermomechanical processing conditions. The tensile test results revealed that yieldingbehavior steadily changed from continuous-type to discontinuous-type as aging temperature increases after 1% pre-strain. After pre-strain and thermal aging treatment in all the steels, the yield and tensile strengths, and yield ratio were increased,while the uniform elongation and work hardening exponent were decreased. In the case of the X80 steel, particularly, thedecrease in uniform elongation was relatively small due to many mobile dislocations in PF, and the increase in yield ratiowas the lowest because a large amount of harder microstructures such as GB, BF, and coarse secondary phases effectivelyenhanced work hardening.

The prediction of the tooth size in the mixed dentition for Korean

Moon, Sung-Hwan,Kim, Seong-Oh,Yu, Hyung-Seong,Choi, Byung-Jai,Choi, Hyung-Jun,Lee, Jae-Ho 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.2

이번 연구의 목적은 혼합치열기 아동에서 미맹출된 견치와 소구치의 크기를 예측하는데 있어서 한국인에 맞는 방정식을 만들기 위함이다. 미맹출 치아의 크기를 예측하는 것은 혼합치열기 교정 진단과 치료계획 수립에 있어서 매우 중요하다. 미맹출된 견치와 소구치 크기를 예측하는 방법은 몇가지가 있지만 그중에서도 가장 흔하게 쓰이는 것이 모이어의 예측표와 다나카와 존스턴의 방정식이 있다. 하지만 그것들은 백인을 위해서 제작된 것이고 치아 크기는 인종에 따라서 다르다고 알려져 있다. 이번 연구에서는 치아크기를 측정하여 하악 영구 절치의 크기 합과 견치 및 소구치의 크기 합 사이의 상관관계를 구하고 회귀방정식을 이용해서 한국인에 맞는 예측표를 만들었다. 연세대학교 치과대학에 재학중인 178명의 한국 학생(남 108명, 여 70명, 평균연령 21.63)을 대상으로 실험하였다. 영구치의 근원심 폭경을 석고모형상에서 calipers를 이용해서 측정하였다. 성별간의 치아 크기는 차이가 있었다(p<0.05). Correlation coefficient는 0.57에서 0.64의 범위였고, standard errors of the estimates 는 여성에서 0.6으로써 남성보다 우수하였다. r^(2)값은 0.27에서 0.41의 범위를 나타내었다. Estimating the size of unerupted teeth is an essential aspect of orthodontic diagnosis and treatment planning in the mixed dentition. Several methods were introduced and used for the prediction. The most common methods among these would be Moyers probability chart and Tanaka and Johnston equations. These are currently used widely, but they were developed for Caucasians. Because there are clear racial differences in teeth size, the objectives of this study were to produce correlation coefficients between the combined mesiodistal widths of the permanent mandibular incisors and those of the canines and premolars for each quadrant, and prediction tables with regression equations, specifically for Korean. 178 young adults (70 women, 108 men, mean age 21.63 years) were selected from the College of Dentistry, Yonsei University, Seoul, Korea. The mesiodistal crown diameters of the permanent teeth were measured with calipers. Significant sexual dimorphism was found in tooth sizes. The correlation coefficients between the total mesiodistal width of the mandibular permanent incisors and those of the maxillary and mandibular canines and premolars were found to be between 0.52 and 0.64. The standard error of the estimatation was better (0.60) for women and the r^(2) values ranged from 0.27 to 0.41 for both sexes, Prediction tables were prepared for Korean. This study showed larger canine and premolar diameters than Tanaka and Johnston's and Moyers' studies which might be due to the racial differences. Further investigations with a larger sample size will be needed for more representative data on the Korean population.

Primary intraosseous carcinoma of the mandible

Hwang, Eui-Hwan,Choi, Yong-Suk,Lee, Sang-Rae 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.4

A very uncommon tumor, primary intraosseous carcinoma (PIOC), is a carcinoma arising within the jaw. The definite diagnosis of PIOC is often difficult as the lesion must be distinguished from alveolar carcinoma that may invade the bone from the overlying soft tissues or from the tumors that have metastasized to the jaw from a distant site. A case of PIOC arising in the mandible is presented. The clinical, radiologic, and histologic features are described. This rare lesion should be considered in any differential diagnosis of a jaw radiolucency.

한국철도의 효율적인 경영과 민영화

조한필(Han Pil Cho),이성환(Sung Hwan Lee) 한국물류학회 2012 물류학회지 Vol.22 No.5

우리나라는 100년 이상 건설과 운영을 함께 담당해오던 국유철도시대를 마감하고 2004년 시설과 운영을 분리하는 철도구조개혁 조치를 단행했지만 막대한 규모의 계속적인 누적 부채 발생으로 만성적인 경영적자 구조에서 벗어나지 못하고 있다. 이에 정부는 KTX 운영권의 민간 개방 등 제 2 철도구조개혁을 위한 민영화를 추진하고 있다. 그러나 이명박 정부가 현재 추진하고 있는 KTX 동일노선에 대한 경쟁체제 도입 방안은 세계적으로 사례를 찾기 어렵고 근본적인 방안으로 미흡한 것이 사실이다. 특히 정부의 민영화 방식은 장기적으로 운임상승과 철도공사의 부채해결 대책이 없고 KTX 운영권의 민간 개방에 따른 사업면허 등 법적 근거 미약 등 정치적, 법적 여러 논란을 빚고 있다. 이에 따라 현 단계에서 분명히 고려되어야 할 것은 철도 운영 경영효율화이며 민영화를 위한 사회적 합의와 기대효과에 대한 긍정적 비전을 제시하는 것이 중요한 것으로 인식했다. 본 연구는 영국, 일본 등 외국의 철도민영화 사례의 시사점을 토대로 우리나라 철도경영의 효율적인 민영화를 위한 방안을 분석, 검토했다. 이미 시설과 운영주체가 분리되어 안정적으로 역할을 수행하는 상황에서 3,381km에 불과한 영업거리 등 취약한 인프라와 현실을 감안하여 국가의 철도투자 책임을 명확히 한다는 측면에서도 지역별, 노선별 분할 민영화보다는 철도운영주체의 일괄적인 책임제민영화 방식으로 추진하는 것이 타당한 것으로 사료된다. Korean railroad has come to the end of government construction and operation management era in 2004 and the railroad system reformation measures was carried out the way of separating the infrastructure from the operation management. But operation deficit continues due to a large accumulated debt. This led the government to push ahead privatization of KTX management for ‘the Second Railroad System Reformation’ through partial privatization. However, President Lee’s government’s current proposal for shared KTX lines is unprecedented anywhere around the globe and is still immature to be implemented as the primary solution. Specifically, the government’s privatization plan does not address any issues regarding future increase in fares and Korean railroad’s debt pay-off in the long run. Also, there are many political and legal conflicts rising from lack of legal grounds such as business license for partial privatization of KTX operation management and solutions for management failure of KORAIL and debt-generating lines. It is necessary at this point to consider the ‘management efficiency’ of the railroad and it is also important to suggest positive vision about privatization to satisfy the social expectations and achieve social and political agreements. This study has analyzed and reviewed ways of effectively privatizing Korea’s railroad management based on implications from previous privatization cases in the U.K and Japan. Based on the fact that infrastructure and operation managements are naturally separated following the train-railroad separation and the fact that the infrastructure management is stable and the operation distance is only 3,381km, it seems more effective to privatize the operation management as a whole rather than executing multiple privatizations of operation management system based on the operating areas and lines.

Original Articles : Clinical significance of occult hepatitis B virus infection in chronic hepatitis C patients

( Jae Young Jang ),( Soung Won Jeong ),( Sung Ran Cheon1 ),( Sae Hwan Lee1 ),( Sang Gyune Kim ),( Young Koog Cheon ),( Young Seok Kim1 ),( Young Deok Cho1 ),( Hong Soo Kim ),( So Young Jin ),( Yun Soo 대한간학회 2011 Clinical and Molecular Hepatology(대한간학회지) Vol.17 No.3

Background/Aims: We investigated the frequency of occult hepatitis B virus (HBV) infection in anti-hepatitis C virus (HCV)-positive individuals and the effects of occult HBV infection on the severity of liver disease. Methods: Seventy-one hepatitis B virus surface-antigen (HBsAg)-negative patients were divided according to their HBV serological status into groups A (anti-HBc positive, anti-HBs negative; n=18), B (anti-HBc positive, anti-HBs positive; n=34), and C (anti-HBc negative, anti-HBs positive/negative; n=19), and by anti-HCV positivity (anti-HCV positive; n=32 vs. anti-HCV negative; n=39). Liver biopsy samples were taken, and HBV DNA was quantified by real-time PCR. Results: Intrahepatic HBV DNA was detected in 32.4% (23/71) of the entire cohort, and HBV DNA levels were invariably low in the different groups. Occult HBV infection was detected more frequently in the anti-HBc-positive patients. Intrahepatic HBV DNA was detected in 28.1% (9/32) of the anti-HCV-positive and 35.9% (14/39) of the anti-HCV-negative subjects. The HCV genotype did not affect the detection rate of intrahepatic HBV DNA. In anti-HCV-positive cases, occult HBV infection did not affect liver disease severity. Conclusions: Low levels of intrahepatic HBV DNA were detected frequently in both HBsAg-negative and anti-HCV-positive cases. However, the frequency of occult HBV infection was not affected by the presence of hepatitis C, and occult HBV infection did not have a significant effect on the disease severity of hepatitis C. (Korean J Hepatol 2011;17:206-212)

Application of CCPM to Construction Project

김영,이영대,김옥수,김성환,박혁,Kim Young,Lee Young-Dae,Kim Ok-Su,Kim Sung-Hwan,Park Hyeok Korean Institute of Construction Engineering and M 2003 건설관리 : 한국건설관리학회 학회지 Vol.4 No.3

The Theory of Constraints (TOC) is an approach and a philosophy that is used to develop specific management techniques. It was first popularized by the novel, The Coal, that applied the principles to operations management. Since 1997 it has found application in two areas within project management The first application is scheduling of a sing1e project to reduce project duration and simplify project control. there is a further application to allocate resources that are shared by concurrent project. It is the objective of this paper to explore the fundamentals of critical chain and to pursue an application of critical chain method to construction project by a case study. 제약이론은 특정한 관리기술을 개발하는데 사용되는 접근방법이며, 철학이다. 운영관리상에 적용되었던 소설 "The Goal"에 의해서 처음으로 널리 보급되었다. 1997이후로 프로젝트관리의 두 가지 영역에서 적용되어 왔으며, 그 첫 번째 적용은 단일프로젝트에 대한 공기단축과 프로젝트 통제관리의 간소화를 위한 공정관리분야이며, 두 번째 적용은 동시에 수행되는 여러 프로젝트에 의해서 공유되는 자원의 효과적 관리이다. 이 논문은 프로젝트 관리에 적용된 제약이론인 애로사슬(Critical chain)의 원리에 대해서 연구하고, 국내의 건설프로젝트에 적용하는 것을 목적으로 한다.

단미음료제(單味飮料劑)를 통한 소갈(消渴)의 치료(治療)에 관한 고찰(考察)

박춘하,위통순,김용성,이경환,Park Choon-Ha,Wei Tung-Sheun,Kim Yong-Sung,Lee Kyung-Hwan 대한한의학방제학회 2002 大韓韓醫學方劑學會誌 Vol.10 No.2

In Oriental medicine, So-gal(消渴) is similar to Diabetes Mellitus in the symptoms. In the medical treatment of So-gal(消渴), one kind of herb medicine is recorded in ancent medicine literatures. That herb medicine is a juice of vegetable drunken with herb medicine of So-gal(消渴). Milk(牛乳汁), human milk(人乳汁), gam-ja-jup(甘蔗汁), wo-jul-jup(藕節汁), li-jup(梨汁), sang-gang-jup(生薑汁) etc. is that. In that juices, Milk(牛乳汁), human milk(人乳汁), gam-ja-jup(甘蔗汁), wo-jul-jup(藕節汁), li-jup(梨汁) have sweety tastes, and cold nature. So they cure So-gal(消渴) come from dry and hot nature. Sang-gang-jup(生薑汁) is different with others in the taste and nature that sweety and hot taste and hot nature. Sang-gang-jup(生薑汁) cure the sequela of So-gal(消渴) by his hot nature. We think In Diabetes Mellitus, that juice can be used by drink for the treatment of diet because of simility between So-gal(消渴) and DM.

Changes in electron and hole traps in GaN-based light emitting diodes from near-UV to green spectral ranges

Lee, In-Hwan,Polyakov, A. Y.,Smirnov, N. B.,Zinovyev, R. A.,Bae, Kang-Bin,Chung, Tae-Hoon,Hwang, Sung-Min,Baek, J. H.,Pearton, S. J. American Institute of Physics 2017 APPLIED PHYSICS LETTERS Vol.110 No.19

Green Synthesis of High-Purity Mesoporous Gold Sponges Using Self-Assembly of Gold Nanoparticles Induced by Thiolated Poly(ethylene glycol)

Lee, Min-Jae,Lim, Sung-Hwan,Ha, Jae-Min,Choi, Sung-Min American Chemical Society 2016 Langmuir Vol.32 No.23

<P>A facile and green synthesis method for mesoporous gold sponges has been developed, which involves a simple mixing of a very small amount, of thiolated-poly(ethylene glycol) (SH-PEG) and citrate-covered gold nanoparticles (Au NPs) in aqueous solution at room temperature. While SH-PEG molecules have been widely used as biocompatible hydrophilic capping agents for Au NPs for stable dispersion in aqueous solution, here they are used as destabilizing agents. When SH-PEG molecules are mixed with citrate-covered Au NPs at the molar ratio ranging from 3 to 20 (SH-PEG/Au NP), mesoporous gold sponges with randomly interconnected 3D network structures are formed within 2 to 3 h. This is-driven by the destabilization of negatively charged citrate molecules, on Au NPs by a small number of SH-PEG molecules bonded on the particle surface, which results in the decrease in zeta potential and thus the assembly of Au NPs into porous sponges. The use of very low concentration of SH-PEG (ca. 20-200 nM) in aqueous solution at room temperature makes the method highly eco-friendly as well as results in high-purity as-synthesized gold sponges (98.17 wt %). The mesoporous gold sponges fabricated with the present method exhibit a high SERS activity, making them highly applicable for sensitive SERS detection of molecules.</P>