Barkhausen noise를 이용한 1Cr-1Mo-0.25V강의 열화도 평가

이종민,안봉영,남승훈,이승석,이억섭,남영현,Lee, Jong-Min,Ahn, Bong-Young,Nahm, Seung-Hoon,Lee, Seung-Seok,Lee, Ouk-Sub,Nam, Young-Hyun 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.7

It is inevitable to evaluate the life of turbine rotor because the operating periods of power plants need to be extended. For the test, seven kinds of specimens with different degradation levels were prepared by the isothermal heat treatment at $630^{\circ}C$. Magnetic methods utilizing Barkhausen noise coercive force($BN_c$) were applied to detect the degradation caused by thermal aging. Magnetic property of material is related with domain dynamics and that is affected by the microstructure of material. Therefore $BN_c$ is very sensitive to the microstructure change of the material. With the increase of degradation, $BN_c$ was decreased and this phenomenon is considered due to precipitations and grain size. The result was compared with Vickers hardness($H_v$) and coercive force($H_c$) to detect the relative variation, and was related with $H_v$ and YS to estimate the change of the mechanical properties with the degradation.

제강슬래그 아스팔트혼합물의 도로포장 성능 평가

이종민,이윤모,이진우,Lee, Jong-Min,Lee, Yun-Mo,Lee, Jin-Woo 한국건설순환자원학회 2021 한국건설순환자원학회지 Vol.16 No.2

R28세포에서 고포도당이 반응성산소종의 생성에 미치는 영향

이종민,김재우,Jong Min Lee,Jae Woo Kim 대한안과학회 2010 대한안과학회지 Vol.51 No.5

Purpose: To investigate the effect of high glucose (HG) on the production of reactive oxygen species (ROS) in retinal precursor R28 cells. Methods: R28 cells were incubated with low glucose (5 mM) or HG (25 mM) for two days. Additionally, the cells were co-exposed to 50 μM N-acetyl cysteine or 100 μM L-arginine. Production of nitric oxide (NO), ROS, and superoxide were assessed by Griess assay, DCFH-DA assay, and modified cytochrome c assay, respectively. Results: HG increased the production of NO, ROS, and superoxide, which were abolished by antioxidants NAC and L-arginine (a substrate for NO production). Conclusions: HG increased ROS production in R28 cells. Thus, HG may cause cellular dysfunction and damage by inducing oxidative stress in retinal ganglion cells. J Korean Ophthalmol Soc 2010;51(5):746-750

말초 정맥주사를 통해 비항암제 발포성 약물을 투약한 성인 환자의 일혈 발생과 위험요인

이종민,이주희,장연수,김연희,Lee, Jong Min,Lee, JuHee,Jang, Yeon Soo,Kim, Yeon Hee 한국중환자간호학회 2018 중환자간호학회지 Vol.11 No.2

Purpose : This study aimed to investigate the incidence of intravenous extravasation and the risk factors associated with the use of peripheral intravenous catheters in adults. Method : This prospective observational study included 203 adult patients admitted to the general ward who received non-chemotherapy vesicant drug infusion treatments. Data were analyzed using frequencies, percentage, means, standard deviations, and odds ratios (ORs) from multiple logistic regressions. Results : The incidence of extravasation was 43.3%. Risk factors for intravenous extravasation included continuous injections (OR=5.35, 95% CI [1.38, 20.83]), and parenteral nutrition (OR=3.53, 95% CI [1.43, 8.73]). Conclusion : The present findings revealed that gastrointernal medicine problems, continuous injection, and parenteral nutrition were related to intravenous extravasation. Further research is necessary to reduce the incidence of extravasation related to peripheral intravenous catheterization in adults, and to prevent secondary complications. Finally, patients should be provided appropriate and continuous care based on the type of intravenous infusion.

국가 대향 레이저 연구시설 소개 - 페타와트 극초단 초강력 레이저 연구시설(PULSER) 구축 및 국내 펨토과학기술 연구 현황

이종민,Lee, Jong-Min 한국광학기기산업협회 2013 光學世界 Vol.144 No.-

펨토초는 1000조 분의 1초를 말한다. $10^{-15}$를 의미하는 단위명이 펨토(Femto)이기 때문에 붙여진 이름이다. 눈을 한 번 깜박이는 시간이 약 10분의 1초, 총알이 물체를 통과하는 데 걸리는 시간이 약 100만 분의 5초인 점을 감안하면 펨토초는 상상하기도 힘들 정도로 빠른 시간인 셈이다. 이런 펨토초 동안 벌어지는 물리, 화학, 생물학적 현상을 연구하는 학문이 펨토과학이며 주로 펨토초 레이저를 이용해 관찰한다. 현재 전 세계적으로 펨토초의 극히 짧은 시간에 1000조 와트(페타와트)의 고출력 레이저를 발생시킬 수 있는 광양자빔 연구시설 구축 사업이 활발하게 진행되고 있다. 국내에서는 광주과학기술원(GIST) 고등광기술연구소가 '극초단 광양자빔 연구시설 설치 운영사업(사업책임자: 이종민 교수)'을 통해 국가 대형 레이저 연구시설인 '페타와트 극초단 초강력 레이저 연구시설(PULSER)'을 최근 구축 완료했다. 이번호에서는 21세기를 이끌 신성장동력 중 하나로 각광 받고 있는 펨토과학기술의 국내 연구 현황과 페타와트 극초단 초강력 레이저 연구시설(PULSER)에 대해 자세히 소개하고자 한다.

도시형 자기부상열차용 굴절형 분기장치의 개발(I)

이종민,조흥제,김인근,Lee, Jong-Min,Jo, Heung-Je,Kim, In-Geun 한국기계연구원 1999 硏究論文集 Vol.29 No.-

This paper presents the status quo of the development of a piecewise bendable switch system for the urban transit MagLev. MagLev system as well as railroad requires switch systems to reach its destination. Requirements of the switch system for commercial lines are high speed operation satisfying about 2-3 minute headway and system reliability, etc. Parallel moving type switch system was installed on the test track of urban transit MagLev in KIMM. In this system, switch operation from one position to another can be done in about 90 seconds. Therefore, we concluded that this system can not satisfy the headway for the commercial lines. We decided to develop a high speed piecewise bendable switch system in which switching can be done in 20 seconds. Designed switch system is very complicated in view of operating mechanism. It consists of 11 segmented girder beams driven by hydraulic cylinders. To gain the idea of a piecewise bendable switch system, we manufactured and tested a 1/5 scale switch model. We are going to construct a full scale piecewise bendable switch system next year.

캠퍼스 발언대

이종민,Lee, Jong-Min 한국과학기술단체총연합회 1994 과학과 기술 Vol.27 No.9

에세이 - 그럼, 우린 어떡하죠?

이종민,Lee, Jong-min 대한건축사협회 2015 建築士 Vol.2015 No.6

Cone Beam Computed Tomography의 두부계측분석을 통한 골격성 제3급 부정교합 환자에서 악교정 수술 후 입술과 주위 연조직의 수직적 변화

이종민,강주완,이종호,김창현,박재억,Lee, Jong-Min,Kang, Joo-Wan,Lee, Jong-Ho,Kim, Chang-Hyen,Park, Je Uk 대한악안면성형재건외과학회 2012 Maxillofacial Plastic Reconstructive Surgery Vol.34 No.5

Purpose: The aim of this study is to evaluate the vertical changes of the lip and perioral soft tissue, following orthognathic surgery in skeletal class III patients by a cephalometric analysis of a cone beam computed tomography (CBCT). Methods: A total of 20 skeletal class III patients, who had bimaxillary surgery with Le Fort 1 osteotomy and bilateral sagittal split ramus osteotomy, were included in this study. The surgical plan for maxilla was posterosuperior impaction with the anterior nasal spine, as the rotation center. Further, the surgical plan for mandible was also posterosuperior movement. The soft tissue changes between lateral cephalogram and CBCT were compared. And the correlations between independent variables and dependent variables were evaluated. Results: There were no significant differences of the soft tissues changes between lateral cephalogram and CBCT. Upper lip philtrum length (SnLs), nasolabial angle increased and upper lip vermilion length (LsStms), lower lip length (StmiB'), lower lip vermilion length (StmiLi), lower lip philtrum length (LiB') and soft tissue lower facial height (SnMe') decreased after surgery. Change of SnLs (${\Delta}$SnLs) was influenced by vertical change of menton (${\Delta}$MeV), and change of LsStms (${\Delta}$LsStms) was influenced by upper lip thickness (ULT). Change of StmiLi' (${\Delta}$StmiLi') were influenced by preoperative overjet. Change of StmiB' (${\Delta}$StmiB') were influenced by preoperative overjet, vertical change of lower incisor (${\Delta}$L1V) and horizontal change of posterior nasal spine (${\Delta}$PNSH). Change of LiB' (${\Delta}$LiB') was influenced by ${\Delta}$L1V and ${\Delta}$PNSH. Change of SnMe' (${\Delta}$SnMe') was influenced by ${\Delta}$MeV, horizontal change of upper incisor (${\Delta}$U1H) and horizontal change of lower incisor (${\Delta}$L1H). ${\Delta}$Nasolabial angle was influenced by change of ULT (${\Delta}$ULT). Conclusion: Both soft tissues and hard tissues can be evaluated by CBCT. Posterosuperior rotation of maxillomandibular complex resulted in increase of upper lip philtrum length and nasolabial angle, while the upper lip vermilion length, lower lip philtrum length, lower lip vermilion length, and soft tissue lower facial height showed a decrease.

호도착기록에 기반한 위치갱신 알고리즘의 성능 분석

이종민,권보섭,맹승렬,Lee, Jong-Min,Kwon, Bo-seob,Maeng, Seung-Ryoul 한국정보처리학회 2003 정보처리학회논문지 A Vol.10 No.4

Location tracking is used to keep track of the location information of a mobile terminal in an idle state for a cail setup between mobile terminals. In this paper, we introduce a location update algorithm based on the call arrival history, which is appropriate for a variable call arrival rate over time. The location tracking strategy which uses the proposed algorithm can find changes in the call arrival rate by maintaining a call arrival history of a mobile terminal, from which a mobile terminal can calculate an appropriate timeout interval for a variable call arrival rate. We show that the proposed scheme is appropriate for a variable call arrival rate by presenting a simple analytical model and analytical results to investigate its performance for both a fixed and a variable call arrival rate. 무선단말기에 도착하는 호의 연결을 위해서 유휴상태에 있는 무선단말기의 위치정보를 관리하는 위치추적 방법이 사용된다. 본 논문에서는 시간이 지남에 따라서 호도착율이 변화할 때에 적합한 호도착기록에 기반한 위치갱신 알고리즘을 제안한다. 이 알고리즘을 사용한 위치추적방법은 무선단말기의 호도착기록을 사용하여 호도착율의 변화를 파악하고, 이를 사용하여 현재의 호도착율에 적합한 타임아웃 주기를 계산한다. 그리고 이 방법에 대한 성능을 평가하기 위하여 고정/가변 호도착율에 대한 분석 모델과 그에 따른 분석 결과를 제시함으로써 호도착율의 변화에 적합함을 보인다.