초음파법을 이용한 구조이음의 접합강도해석

장철섭,오승규,이원 한국공작기계학회 2005 한국생산제조학회지 Vol.14 No.2

This article has been investigated the use of FIT for adhesive joints analysis between metal sheets. The method is based on the measurement of the reflection wave at the metal/adhesive interface. After describing briefly the physical aspects of the phenomenon, an index is defined to detect defective zone of the joint(both for the lack of adhesive and for insufficient adhesion); the influence of the experimental variables(variable stress..,) on the measurement is discussed. By means of a control experiment it is shown that stress variation in adhesive joints are separate to be distinguished. In this paper, Nondestructive evaluation in adhesive joints are evaluated together with ultrasonic testing and finite element analysis.

개인방사선피폭선량평가

이형섭,김장렬,윤석철,이상윤 대한방사선 방어학회 1994 방사선방어학회지 Vol.19 No.2

최근, 개인방사선피폭선량평가에 관한 기술기준이 과학기술처에 의해 고시됨에 따라 국내에서도 개인선량계를 이용한 체외피폭선량평가결과의 신뢰성 문제가 크게 대두되고 있다. 한국원자력연구소에서는 이러한 구내의 상황을 인식하고 자체적인 신뢰성 확보를 위해 미국의 Oak Ridge국립연구소의 주관하에 개인피폭선량의 평가에 관한 국제상호비교검증시험(Personnel Dosimetry Intercomparison Study ; PDIS) 을 수행하였다. 비교 검증시험에는 한국원자력연구소에서 사용하고 있는 Teledyne PB-3 열형광선량계가 사용되였으며 선량게산 알고리즘은 Teledyne PB-3 version1.5-1989를 사용하였다. 본 연구에서는 지금까지 실시된 PDIS의 결과를 요약하고 현재 PB-3 시스템의 개인선량평가성능에 대해 고찰하였으며, 선량평가절차에 대한 문제점 도출을 통하여 직업적 방사선피폭선량 평가능력의 향상을 위한 방안을 제시하였다. Recently, the Ministry of Science and Technology issued a Ministerial Ordinance (N0 1992-15) about the technical criteria on personnel radiation dosimetry. In today's climate, it is important to demonstrate and document that the processor's systems and services to others meet national standards of quality. The purpose of this study is to verify the performance of the Teledyne PB-3 personnel dosimetry system that is generally used in Korea Atomic Energy Research Institute (KAERI) by intercomparison with Oak Ridge National Laboratory. The KAERI has been participated in this personnel dosimetry intercomparison study(PDIS) program since 1991 and it could be possible to test and calibrate personnel monitoring system. This report presents a summary and analysis of by about 50 does equivalent measurements reported for PDIS-16 through 18 (1991-1993) with emphasis on neutron does equivalent sensitivity, accuracy and methods to improve personnel dosimetry performance are also discussed.

단기반응성 정신병 환자와 정신분열증 환자의 임상적 비교연구

김철주,장무성,엄용섭 大韓神經精神醫學會 1989 신경정신의학 Vol.28 No.1

To compare the clinical characteristics of brief reactive psychosis with those of schizophrenia, the authors selected 50 patients of brief reactive psychosis meeting with DSM-Ⅲ criteria and 50 patients of schizophrenia meeting with both DSM-Ⅲ and RDC criteria. All patients were admitted to the psychiatric ward of Pusan Paik Hospital from Apr. 1, 1984 to Mar- 31, 1987 The results obtained from this retrospective study were as fellows: 1) Brief reactive psychosis was apparently more common in women(74%) and usually appeared In early adulthood, but had more wider age distribution than schizophrenia. 2) Although their educational levels were lower than that of schizophrenics, the patients of brief reactive psychosis showed better marital and premorbid adjustment than the schizophrenics. 3) In brief reactive psychosis, the premorbid personality was more variable than in schizophrenics and the most vulnerable personality was hystrionic(22%) and dependent(18%). 4) The major psychosocial factors predisposed to the development of brief reactive psychosis were marital or financial crisis(26% ), death or separation(72% ), academic or occupational problems(16%) and health problems(12% ) in order of frequency. 5) On admission, insomnia(92%), emotional turmoil(82%) and hallucination(66%) were more frequent in the patients of brief reactive psychosis than in the patients of schizophrenia. Although the Schneider's first rank symptoms were less frequent in the former, it was surprising that they were present in 32% of them. 6) Almost all of the patients with visual hallucination were reactive psychotic patients and 64% of the hallucinatory Images of them were the deads or ghosts. 7) During the course of admission, the majority(60% ) of the patients of brief reactive psychosis were treated with daily dosage under 200mg of chlorpromazine equivalent.

척추경 나사못을 이용한 척추 유합술에서 고정범위에 따른 인접 추간판의 압축 거동 분석

안면환,안종철,이수호,정일섭,이춘열,이장우 영남대학교 의과대학 2003 Yeungnam University Journal of Medicine Vol.20 No.2

요추부 척추에 기구를 시술한 유한요소 복합체 모델을 이용하여 제 4-5 요추간판에 대한 해석을 수행한 결과, 근육의 작용을 케이블과 케이블 가이드로써 단순화 모사한 follower 하중에서 수직하중인 경우보다 높은 압축력을 나타내어 더욱 안정함을 보였고 불안정성의 원인이 되는 전단력과 굽힘모멘트의 발생은 미미하였다. 장분절 고정에 의한 인접 분절에 전단력이 증가됨을 실험적으로 보였는데, 이는 장분절 고정이 퇴행성 변화 촉진에 기여할 것으로 추정된다. Background: Confirm the stability of intervertebral disc sustaining each fused lumbar spine cases, comparing vertical compression, A-P shear force and rotational moment on intervertebral disc of instrumented lumbar spine with simple vertical compression load and follower load using finite element analysis. Materials and Methods: We analyze the stability of intervertebral disc L4-5 supporting fused lumbar spine segments. After performing finite element modelling about L1-L5 lumbar vertebral column and L1-L4 each fusion level pedicle screw system for fused lumbar spine fine element model. Intervertebral discs with complex structure and mechanical properties was modeled using spring element that compensate stiffness and tube-to-tube contact element was employed to give follower load. Performing geometrical non-linear analysis. Results: The differences of intervertebral disc L4-5 behavior under the follower compression load in comparision with vertical compression load are as follows. Conclusion: As a result of finite element interpretation of interpretation of instrumented lumbar spine, the stability of L4-5 sustaining fused lumbar segment, the long level fused lumbar spine observed hing stability under follower load. This research method can be the basis tool of effects prediction for instrumentation, a invention of a more precious finite element interpretation model which consider the role of muscle around the spine is loaded.

안구적출에 따른 위둔덕의 Calbindin D-28k과 c-fos의 변화에 관한 연구

김명,김기훈,김주영,하현철,안명수,김장민,조향훈,정명섭,장인엽 朝鮮大學校 附設 醫學硏究所 2005 The Medical Journal of Chosun University Vol.30 No.2

Changes of Calbindin D-28k- and c-fos-immunoreactivities in the superior collicuclus after Eye Enucleation. Objective and methods: Calcium-binding proteins (CBPs) play an important role in the protection, differentiation and reorganization of the central nervous system. The effects of neonatal retinal deafferentation on a CBPs, calbindin D-28k were examined immunohistochemically in the superficial layer of the rat superior colliculus. Also early gene familly c-fos was examined to evaluate the neuronal characteristics in the superior colliculus after monocular enucleation. Results: On the experimental side of superior colliculus, the number of calbindin D-28k-immunoreactive (IR) cells was reduced (77.4% compared to control), but not fibers. Appearance of c-fos-like immunoreactivity was represented much more in the ipsilateral superior colliculus than contralateral side within 24h after eye enucleation. Conclusion: These results suggest that the changes of retinotectal projection may alter the expressional pattern of calbindin D-28k and c-fos expression.

관절각과 지면반발력을 이용한 보행 단계의 분류

채민기(Min-Gi Chae),정준영(Jun-Young Jung),박철제(Chul-Je Park),장인훈(In-Hun Jang),박현섭(Hyun Sub Park) 제어로봇시스템학회 2012 제어·로봇·시스템학회 논문지 Vol.18 No.7

This paper proposes the gait phase classifier using backpropagation neural networks method which uses the angle of lower body’s joints and ground reaction force as input signals. The classification of a gait phase is useful to understand the gait characteristics of pathologic gait and to control the gait rehabilitation systems. The classifier categorizes a gait cycle as 7 phases which are commonly used to classify the sub-phases of the gait in the literature. We verify the efficiency of the proposed method through experiments.

직사각핀의 비오트수에 따른 냉각효과에 대한 해석

장철섭(Chul-Sub Jang) 산업기술교육훈련학회 2020 산업기술연구논문지 (JITR) Vol.25 No.3

The performance of a rectangular fin, the relative value of the performance for L=0.1, and the ratio of the heat transfer from the fin tip to the total heat transfer from the rectangular fin were investigated using a two-dimensional analytical method. The variables are the Biot number and non-dimensional fin length. The relative resistance, effect, and efficiency increase as the non-dimensional length increases for a small Biot number (Bi≤0.1). On the other hand, the relative resistance and effect decrease and the relative efficiency increases as the non-dimensional length increases for a large Biot number (Bi≥0.7).

G2A Protects Mice against Sepsis by Modulating Kupffer Cell Activation: Cooperativity with Adenosine Receptor 2b

Li, Hong-Mei,Jang, Ji Hye,Jung, Jun-Sub,Shin, Jiseon,Park, Chul O.,Kim, Yeon-Ja,Ahn, Won-Gyun,Nam, Ju-Suk,Hong, Chang-Won,Lee, Jongho,Jung, Yu-Jin,Chen, Jiang-Fan,Ravid, Katya,Lee, H. Thomas,Huh, Won- American Association of Immunologists 2019 Journal of Immunology Vol. No.

<P>G2A is a GPCR abundantly expressed in immune cells. G2A<SUP>−/−</SUP> mice showed higher lethality, higher plasma cytokines, and an impaired bacterial clearance in response to a murine model of sepsis (cecal ligation and puncture), which were blocked by GdCl<SUB>3</SUB>, an inhibitor of Kupffer cells. Anti–IL-10 Ab reversed the impaired bacterial clearance in G2A<SUP>−/−</SUP> mice. Indomethacin effectively blocked both the increased i.p. IL-10 levels and the impaired bacterial clearance, indicating that disturbed PG system is the proximal cause of these phenomena. Stimulation with LPS/C5a induced an increase in <I>Escherichia coli</I> phagocytosis and intracellular cAMP levels in G2A<SUP>+/+</SUP> peritoneal macrophages but not G2A<SUP>−/−</SUP> cells, which showed more PGE<SUB>2</SUB>/nitrite release and intracellular reactive oxygen species levels. Heterologous coexpression of G2A and adenosine receptor type 2b (A2bAR) induced a synergistic increase in cAMP signaling in a ligand-independent manner, with the evidence of physical interaction of G2A with A2bAR. BAY 60-6583, a specific agonist for A2bAR, increased intracellular cAMP levels in Kupffer cells from G2A<SUP>+/+</SUP> but not from G2A<SUP>−/−</SUP> mice. Both G2A and A2bAR were required for antiseptic action of lysophosphatidylcholine. These results show inappropriate activation of G2A<SUP>−/−</SUP> Kupffer cells to septic insults due to an impaired cAMP signaling possibly by lack of interaction with A2bAR.</P>

A Verification for Multiple Are Stereotaxic Radiotherapy

Jang, Hong Seok,Yoon, Sei Chul,Shinn, Kyung Sub,Kim, In Ah,Bahk, Yong Whee CATHOLIC MEDICAL CENTER 1991 Bulletin of the Clinical Research Institute Vol.19 No.2

External stereotaxic irradiation of intracranial lesions has recently gained its interest in the fields of not only radiation oncology but also neurosurgery. Its main goal is to deliver large doses to a relatively small target volume. Authors present methods of the stereotaxic radiosurgical irradiation using 6 MV linear accelerator (Nelac-6) and isodose distribution by therapeutic computer (Therac 2000). We attempt to demonstrate the dose distribution on verification films.

Measurement of Radiation Using Tissue Equivalent Phantom in ICR Treatment

Jang,Hong-Seok,Suh,Tae-Suk,Yoon,Sei-Chul,Ryu,Mi-Ryeong,Bahk,Yong-Whee,Shinn,Kyung-Sub 대한방사선 방어학회 1995 방사선방어학회지 Vol.20 No.1

연구목적 : 자궁경부암환자에서 자궁강내 근접 방사선조사시 선원 배열에 따른 선량분포와 임상적으로 중요한 표식점인 A 및 B점 선량값에 대한 정확성을 평가하기 위하여 조직등가 팬톰을 제작하고 필른선량계측법을 적용하여 측정한 후, 이를 along-away에 의한 계산과 전산화치료계획장치에 의한 값과 비교 분석하였다. 대상 및 방법 : 자궁강내 근접 방사선조사시 치료상태를 그대로 묘사할 수 있게 아크릴과 물을 이용하여, 인체조직등가 팬톰을 제작한 후 자궁경부암의 자궁강내 근접 방사선조사를 시행하는 것과 똑같이 Fletcher-Suit-Delclos applicator를 삽입하였다. Tandem에 15.7mgㆍRa-eq의 방사능을 가진 ??Cs tube를 2㎝ 간격으로 3개 주입한 후, A 점에 해당되는 단면에 수직방향과 평행방향으로 각각 필름을 팬톰 간극에 삽입하였고, 또한 팬톰표면의 방사선량분포측정을 위하여 팬톰표면을 필름으로 감싸서, 1시간 조사하였다. 필름에 현상된 음영을 필름농도계를 이용하여 농도분포를 측정하여, A 점에 대한 방사선량을 환산 하였고, 전체적인 선량분포도를 얻었다. 이러한 측정값과 전산화치료계획장치를 이용하여 얻은 A점 값, along-away표에 의한 A점 선량을 비교하였고, 필름에 의한 선량분포와 컴퓨터에 의한 선량분포를 서로 비교하였다. 결과 : A 점에 대한 필름 측정치는 시간당 51.2 cGy였고, 전산화치료계획장치에 의한 계산값은 시간당 46.7 cGy, along-away 표에 의한 값은 시간당 47.9 cGy여서 약 10% 이내로 비교적 일치하였다. 필름을 계측하여 얻은 선량분포와 전산화치료계획장치의 계산에 의한 선량분포는 비슷한 모습을 보여주었다. 결론 : 본 연구에서 아크릴과 물을 이용하여, 간단하고 경제적인 방법으로 인체조직등가팬톰을 제작할 수 있었고, 이러한 간단한 팬톰을 이용하여 비교적 효과적으로 자궁강내 근접 방사선조사시 사용하는 밀봉선원인 ??Cs tube의 선량에 대한 품질검사는 물론, 전산화치료계획장치를 이용한 값과 이론적인 식을 바탕으로 수작업으로 계산한 값, 그리고 실험으로부터 구한 실측값을 비교 검토함으로써 치료계획의 신뢰성을 확인할 수 있었다. This study is to compare A point doses in human pelvic phantom by film dosimetry, computer planning and manual calculation by using of along-away table. We developed tissue equivalent human pelvic phantom composed of our pieces of cylindrical acryl tubes with water, to simulate intracavitary rdiation (ICR) in patients with cervix cancer. When the phantom assembled from 4 pieces, it has a small space for inserting Fletcher-Suit-Delclos applicator like a human vagina. Fletcher-Suit-Delclos applicator inserted into the space was packed tightly with furacin gauzes, and three ??Cs sources with radioactivity of 15.7 mgㆍRa-eq were inserted into the tandem. For the film dosimetry, two pieces of X-OMAT V film (Kodak Co.) of which planes include point A, were arranged orthogonally in the slits between phantoms. A point dose and iso-dose curves were measured by means of the optical densitometry. A point doses by film dosimetry, RTP system and manual calculation by using of along-away table were compared, and iso-dose curves by film dosimetry and computer planning were also compared. The dose of a point was 51.2 cGy/hr by film dosimetry, 46.7 cGy/hr by RTP system and 47.9 cGy/hr by along-away table. A point dose by computer planning was similar to the dose by calculation using of along-away table with acceptable accuracy (±3%), however, the dose by film dosimetry was different form two others with about 10% error. Since most clinical beams contains a scatter component of low energy photons, the correlation between optical density and dose becomes tenuous. In addition, film suffers from several potential errors such as changes in processing conditions, interfilm emulsion differences, and artifacts caused b air pockets adjacent to the film. For these reasons, absolute dosimetry with film is impractical, however, it is very useful for checking qualitative patterns of a radiation distribution. In future, solid state dosimeter such as TLD must be used for the dosimetry of ionizing radiation. When considerable care is used, precision of approximately 3% may be obtained using TLD.