• Proceedings of the Korean Vacuum Society Conference
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• 2009.08a
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• pp.189-189
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• 2009

• Proceedings of the KIEE Conference
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• 2007.10c
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• pp.10-13
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• 2007

System requirements (SRs), which describe the technical attributes to be satisfied by a desired system, serve as a fundamental guideline for system development. Standard methods and processes to define SRs are suggested in systems engineering literature. But in practice, we encounter many difficulties in defining and managing SRs since there are few experiences on development of complex systems in accordance with systems engineering processes of development. In this paper, to expanding SRs management experiences in a working-level, we reviewed problems occured in SRs defining process in 'Urban MAGLEV Train Project', and analyzed our activities to adjust and solve the problems.

• Proceedings of the KIEE Conference
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• 2008.05a
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• pp.173-174
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• 2008

Time Domain Reflectometry(TDR) 기법을 응용하여 극초단파 대역을 포함하는 광대역 주파수범위에서 절연유의 유전율을 쉽게 측정할 수 있는 기법을 제안하였다. 수 GHz 이상의 대역에서의 절연유 유전율은 전자파를 이용한 전력용 변압기 부분방전 발생위치 추정에 필수적인 정보이나 기존의 방법으로 간단히 측정할 수 없었다. 본 기법은 동축구조에서 전자파 진행속도가 절연매질 유전율의 함수로 인가된 펄스파의 매질에 대한 동축선로에서 진행시간을 계산함으로써 유전율을 구하는 간단한 방법이다. 제안한 새로운 방법을 이용해 절연유중 1종4호 신유의 경우 광대역에서의 유전율은 2.1임을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.526-529
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• 2002

Lysis of erythrocytes isolated from human, rabbit, and mouse blood samples was investigated with the culture supernatant of Xenorhabdus nematophilus in a primary form. Prior to use, the culture supernatant of the bacteria was concentrated and the concentrate was dialyzed against Tris-HCl buffer (10 mM, pH 8.1) by ultrafiltration using PM-5 membrane with a molecular weight cut-off of 5,000. At $30^{\circ}C$, the supernatant exhibited no lytic activity towards three types of erythrocytes. However, at $4^{\circ}C$, the supernatant showed selective lytic activity towards rabbit erythrocytes within 90 min. yet did not lyze human or mouse erythrocytes. Microscopic examination clearly revealed that most of the rabbit erythrocytes had been fumed into ghost forms.

• The Korean Journal of Pharmacology
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• v.19 no.1
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• pp.115-122
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• 1983

The influences of diazepam and naloxone on the increase of plasma corticosterone level induced by morphine, pentazocine, ACTH, or picrotoxin were investigated in male mice. The results obtained were summarized as follows: 1) The increase induced by morphine or pentazocine of plasma corticosterone level was not affected by naloxone pretreatment but markedly suppressed by diazepam pretreatment. 2) The increase induced by ACTH of plasma corticosterone level was not affected by diazepam or naloxone pretreatment. 3) The picrotoxin markedly increased plasma corticosterone level, and the inceease was not affected by diazepam or naloxone pretreatment. This above results suggest that the increase induced by opioids of plasma corticosterone level seems to be rather related with other than opiate- or GABArerecptor.

• Bulletin of the Korean Space Science Society
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• 2005.04a
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• pp.34-34
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• 2005

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.47-51
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• 1995

• Journal of Korean Neurosurgical Society
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• v.43 no.3
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• pp.169-171
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• 2008

Giant lymph node hyperplasia (Castleman's disease) is a nonneoplastic lymphoproliferative disorder of unknown etiology that usually occurs in the chest. Its morphological recognition is based on a composition of various histological features. The mass is often asymptomatic, but it can cause nonspecific thoracic symptoms, such as regional pain. This disease can be found wherever lymph nodes are present, but two-thirds of these tumors are found in the chest, along the tracheobronchial tree in the mediastinum or lung hilus. However, we experienced an unusual case of Castleman's disease as a cause of back pain that was localized in the posterior mediastinum bordering the chest wall.

• The Science & Technology
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• v.31 no.4 s.347
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• pp.43-67
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• 1998

과학기술이 발전하기 위해서는 일반인들의 지지기반이 튼튼해야 한다. 선진 여러 나라는 과학에 대한 일반인들의 이해도가 떨어지면 사회 발전을 저해하는 결과를 가져온다는 인식아래 국가가 과학기술 풍토 조성 사업에 적극 뛰어들고 있다. 우리나라도 1967년 과학기술처가 발족되면서 과학기술풍토조성사업을 주요시책으로 삼아 오늘에 이르고 있다. 우리나라는 70년대 전국민과학대중화 운동을 한때 활발하게 펼친 적이 있다. 그러나 과하기술 풍토조성은 예산의 뒷받침을 받지못해 지지부진하다. 과학기술풍토조성의 중요성과 우리와 선진국의 실태, 그리고 문제점을 짚어보고 방안을 분야별로 점검해 보았다.

• Journal of Korean Neurosurgical Society
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• v.37 no.4
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• pp.296-299
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• 2005

We report a case of primary central nervous system(CNS) lymphoma in an organ recipient. A 33-years-old man who underwent a renal transplantation 3years previously presented with headache and vomiting. In Brain computed tomography scans and magnetic resonance images showed multiple periventricular cystic rim enhancing masses. Pathologic diagnosis by stereotactic biopsy revealed malignant non-Hodgkins B-cell lymphoma. After pathologic confirmation, methotrexate chemotherapy and whole brain radiation therapy were done. Having experienced such a case, the authors strongly recommend to add primary CNS lymphoma as one of the differential diagnoses to brain abscess, metastatic brain tumor and glioblastoma multiforme in cases of multiple ring enhancing periventricular lesions of immunocompromised patient or organ recipient.