• 제목/요약/키워드: Nam Byung Gil

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안전한 e-Navigation을 위한 해상교통관제 시스템의 정보교환 보안구조 설계 (A Security Architecture of the inter-VTS System for shore side collaboration of e-Navigation)

  • 이병길;한종욱;조현숙;박남제
    • 한국항해항만학회지
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    • 제36권1호
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    • pp.1-7
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    • 2012
  • 해양 분야에서 "e-Navigation"의 개념이 2005년 처음 소개된 이후, 최근 2~3년 전부터 국제해사기구(IMO)와 항로표지협회(IALA)에서 이행전략과 기술 표준화가 급속히 추진되고 있다. 특히 해상교통관제시스템(VTS : Vessel Traffic Service)은 항행지원정보교류가 가능한 육상국으로서 선박 통항의 안전과 효율성을 증진시키고 환경을 보호하는 e-Navigation의 핵심적 시스템으로 인식되고 있다. 최근 IALA VTS Committee에서는 출항에서 도착항까지 항행지원을 위하여 VTS 시스템간 정보 교류(IVEF:Inter-VTS Data Exchange Format)에 대한 요청으로 표준화가 진행되고 있다. 그러나 이러한 해상의 실시간 선박 교통흐름 정보는 국가적으로도 보안에 민감한 정보로서, 테러 등 역기능에 대한 우려가 있어, 안전한 정보교환은 필수적인 요소이다. 따라서 본 논문에서는 상호연동을 위한 보안 프로토콜을 설계하고 안전한 데이터 전송을 위한 보안 구조를 제시하고자 한다.

경사진 사석층의 지지력에 관한 원심모형실험 및 수치해석 (Centrifuge Model Experiments and Numerical Analysis for the Bearing Capacity of Sloped Rubble Mound)

  • 이명욱;박병수;정길수;유남재
    • 산업기술연구
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    • 제24권B호
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    • pp.95-105
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    • 2004
  • This paper is an experimental and numerical research works about the effects of the b earing capacity of sloped rubble mound on the density of rubble mound and the position of footing. Centrifuge model tests were performed to investigate the bearing capacity of rubble m ound by changing the density of rubble mound and the location of loading in forms of s trip loading to simulate the caisson. Materials of rubble mound used in the model tests were crushed rocks having similar value of uniformity coefficient to the value in field. Two different relative densities of 80% and 90% were prepared during tests. The dimens ions of centrifuge model were trapezoidal shape of model mound having the bottom wid th of mound, 30cm and height of mound, 10cm. Gravity level applied during the centrif uge test was 50G. Surcharge loading in the forms of strip loading was applied on the t op of the sloped model mound. Tests were carried out by changing the position of loadi ng. The rigid model footing was located in the center of top of the model rubble mound and the edge of model footing was at the crest of mound. Test results were analyzed by using the limit equilibrium methods proposed by Meyer hof(1957) and Bowles(1982) and the numerical approach with FLAC being available com mercially software. For the numerical estimations with FLAC, the rubble mound was si mulated with the constitutive relationship of Mohr-Coulomb elasto-plastic model.

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쇄석의 진동다짐 특성에 관한 실험적 고찰 (An Experimental Study on the Characteristics of Vibro-compaction of Crushed Stones)

  • 정길수;박병수;홍영길;유남재
    • 산업기술연구
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    • 제24권B호
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    • pp.89-94
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    • 2004
  • This Study is results of experimental works to investigate the characteristics of vibro-compaction of crushed stones having coarse grain sizes. For testing material, crushed stone, sieved within very narrow ranges of grain size distribution, was used. Cyclic loading apparatus was used to apply cyclic loading to the specimen prepared in the mold. Tests were performed by changing the ratio of the maximum to the minimum stress, frequency and the magnitude of the maximum and the minimum stresses. Settlement of specimen due to cyclic loading was measured to analyze the compaction efficiency and sieve analysis test after cyclic loading test was also carried out to find the crushing rate of the specimen. As results of cyclic loading test, normalized settlement in terms of specimen height tends to be converged around loading cycle number of 1500. The magnitude of normalized settlement is in the range of 3.11 ~ 8.57%. The crushing rate is in the range of 4.46 ~ 8.78%. Normalize settlement and the crushing rate tend to increase with decreasing the ratio of the maximum to the minimum stresses and they tend to increase with increasing the frequency and the magnitude of the maximum and the minimum stresses for the given ratio. In conclusions, compaction rate of crushed stone is controlled by the dynamic stress (difference between the maximum and the minimum stresses) and the crushing rate is dominated by applied energy to the specimen.

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모래다짐말뚝과 널말뚝으로 처리된 연약점토지반의 거동 (Behavior of Soft Ground Treated with Sand Compaction Piles and Sheet Piles)

  • 유남재;정길수;박병수;김경수
    • 산업기술연구
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    • 제26권B호
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    • pp.93-99
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    • 2006
  • Centrifuge model experiments were performed to investigate the confining effects of the sheet piles, installed to the sides of soft clay ground treated with sand compaction piles, on the bearing capacity and concentration ratio of composite ground. For the given g-level in the centrifuge model tests, replacement ratio of SCP and the width of surcharge loads on the surface of ground with SCP, the confining effects of installing the sheet piles on the edges of SCP ground on the bearing capacity, change of stress concentration ratio and failure mechanism were investigated. Kaolin, one of typical clay mineral, and Jumunjin standard sand were used as a soft clay ground and sand compaction pile irrespectively. As results of experiments, lateral confining effect by inserting the model sheet piles fixed to the loading plate was observed. For the strip surcharge loading condition, the yielding stress intensity in the form of the strip surcharge loads tends to increase with increasing the embedded depth of sheet piles. The stress concentration ratio was found not to be influenced consistently with the embedded depth of sheet piles whereas the effect of stress intensity on stress concentration ratio shows the general trend that values of stress concentration ratio are relatively high at the initial stage of loading and tend to decrease and converge to the certain values. For the failure mechanism in the case of reinforced with sheet piles, displacement behavior related to the punching failure, settlement right beneath the loading plate occurred since the soil was confined with sheet piles, was observed.

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활락단(活絡丹)이 항염(抗炎), 진통(鎭痛) 및 항혈전(抗血栓)에미치는 영향(影響)에 대(對)한 연구(硏究) (Study on the Anti-inflammatory, Analgesic and Anticoagulative effects of Whalrakdan in the experimental animals)

  • 강승범;박종운;김종길;조남수;문병순
    • 대한한방내과학회지
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    • 제20권1호
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    • pp.57-72
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    • 1999
  • This study was designed to elucidate the anti-inflammatory, cardiovascular, anti-thrombotic, and analgesic effect of Whalrakdan. The anti-inflammatory effects was measured by the method of carrageenin induced edema, protein leakage test using CMC-pouch, and the effect of Whalrakdan on the cardiovascular system was observed by the change of flow rate of Ringer solution in the vascular system in the ear of rabbit. and the contraction and dilatation of rat tail artery. Death rate, platelet aggregation, plasma coagulation activity, antithrombin activity was observed for the measurement of the anti-thrombotic effect of Whalrakdan, and the analgesic effect was measured by the acetic acid method and hot plate method. The result was as follows: 1. After 2 or 3hour of Whalrakdan administration, carrageenin induced edema and CMC-pouch protein leakage was significantly decreased. 2. The slight anagesic effect of Whalrakdan extract was confirmed by the observation of writhing syndrome, paw licking time, and escape time. 3. The droplet of Ringer solution increased according to the increase of concentration of Whalrakdan extract, and the vasoconstriction decreased dependantly to the concentration of Whalrakdan extract. 4. The anti-thrombotic effect of Whalrakdan was observed by the decrease of death rate, the inhibition of platelet aggregation, and the increase of anti-thrombin activity.

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조선(朝鮮) 산학(算學)과 수리정온(數理精蘊) (Mathematics of Chosun Dynasty and $Sh\grave{u}\;l\breve{i}\;j\bar{i}ng\;y\grave{u}n$ (數理精蘊))

  • 홍영희
    • 한국수학사학회지
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    • 제19권2호
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    • pp.25-46
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    • 2006
  • 서양 수학이 조선에 전입된 과정과 그 영향을 연구한다. 초기 과정은 최석정(崔錫鼎)$(1645\sim1715)$의 구수약(九數略), 홍정하(洪正夏)$(1684\sim?)$의 구일집(九一集), 중기 과정은 황윤석(黃胤錫)$(1719\sim1791)$의 이수신편(理藪新編), 홍대용(洪大容)$(1731\sim1781)$의 주해수용(籌解需用)을 통하여 조사한다. 서양 수학은 시헌력(時憲曆)의 도입과 함께 천문학의 연구를 위하여 도입되었다. 수리정온(數理精蘊)을 가장 잘 이해한 학산(鶴山) 초부(樵夫)의 수리정온보해(數理精蘊補解)(1730?)를 연구하고 서양 수학을 구조적으로 이해한 19세기의 이상혁(李尙爀)$(1810\sim?)$, 남병길(南秉吉)$(1820\sim1869)$을 연구한다.

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조선(朝鮮) 산학(算學)의 퇴타술 (Finite Series in Chosun Dynasty Mathematics)

  • 홍성사
    • 한국수학사학회지
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    • 제19권2호
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    • pp.1-24
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    • 2006
  • 조선 산학의 퇴타술의 역사를 연구한다. 이상혁(李尙爀)$(1810\sim?)$의 익산(翼算)(1868)이 출판되기 전의 역사와 익산(翼算)의 결과로 나누어 연구한다. 경선징(慶善徵)$(1616\sim?)$의 묵사집산법(默思集算法)부터 남병길(南秉吉)$(1820\sim1869)$의 산학정의(算學正義)(1867)까지의 산서를 통하여 익산(翼算) 이전의 퇴타술은 큰 발전을 이루지 못한 것을 조사한다. 이상혁(李尙爀)은 조선(朝鮮) 산학(算學)에서 가장 독창적인 방법을 써서 새로운 결과를 얻어낸다. 그는 퇴타술을 구조적으로 해결하고, 또 새로운 문제인 절적(截積)과 이를 위한 분적법(分積法)을 도입하여 이의 구조도 완전히 밝혀내었다.

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갑상선 결절에서 세침흡인검사와 동결조직검사의 의의 (Significance of Fine-Needle Aspiration Cytology and Frozen Section Biopsy in Thyroid Nodules)

  • 송달원;손수길;최종원;신승진;김태종;남성일;안병훈
    • 대한두경부종양학회지
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    • 제19권1호
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    • pp.52-57
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    • 2003
  • Background and Objectives: Fine needle aspiration (FNA) cytology is a simple, safe and relatively accurate procedure of diagnosing thyroid nodules. Although the frozen section biopsy is well known as more reliable method than FNA and has high specificity, whether it is necessary it leaves room for adverse criticism. Authors have compared preoperative FNA cytology and frozen section biopsy with permanent histologic findings and evaluated the significance of FNA cytology and frozen section biopsy. Materials and Methods: The medical records of 110 patiens who underwent FNA cytology and frozen section during thyroidectomy from September. 1997 to December. 2001 at the Department of Otolaryngology, School of Medicine, Keimyung University were analyzed retrospectively. Results: Sensitivity, specificity, accuracy of FNA was 75%, 91.4%, and 85.5% respcetively. Sensitivity, specificity and accuracy rate of frozen section biopsy were 92.5%, 100% and 97.3% respectively. Conclusion: FNA is simple, with rare complication and its diagnostic accuracy is comparatively so high that it is being used as primary test to diagnosis thyroid nodules. But frozen section is more accurate and may be helpful to suspicious FNA findings or if it beyond capacity of FNA. Therefore despite of the fact that the intra-operative frozen is more expensive and time consuming, it is very helpful to the treatment of thyroid nodules by using jointly with FNA.

식품 클러스터의 잠재성 분석: 경남지역을 중심으로 (Potentials of Regional Clustering: the Case of Food Industry at Gyeongsangnam-Do)

  • 김성용;안병일;김윤식;이미숙;남경수;길수민
    • 농업생명과학연구
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    • 제43권6호
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    • pp.117-127
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    • 2009
  • 이 연구는 식품산업의 경쟁력 확보 수단으로 클러스터에 대한 논의가 세계 각국에서 활성화되고 있음을 감안하여 경남지역의 식품산업이 클러스터로 형성 및 발전이 가능한지를 분석하였다. 클러스터의 잠재성 평가는 2차 자료로 측정이 가능한 5가지 지표를 사용하여 분석하였다. 평가지표로는 클러스터의 절대적 규모, 상대적 규모, 전문화, 지배력, 집적도가 사용되었다. 측정지표의 분석결과 경남의 식품산업은 클러스터 조성시 경제적 효과의 창출이 가능하며, 경쟁력 뿐 만 아니라 지역전문화와 지배력을 갖춘 것으로 평가되어 잠재적 클러스터 기준에 합치하는 것으로 나타났다.

2급 응급구조사 양성과정 개선방안 연구 : 양성기관 현황 및 지정기준 검토 (Improvement in emergency medical technician-basic training program : a review of the status of training institutions and designation criteria)

  • 이남종;신동민;김병우;박시은;유은지;윤병길;윤성우;윤형완;이경열;최재웅;황성훈
    • 한국응급구조학회지
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    • 제23권2호
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    • pp.139-151
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    • 2019
  • Purpose: To discuss the records and legal standards of emergency medical technician training institutions in Korea and abroad, to identify the problems, and to provide the basic resources for improving the EMT-basic training institutions. Methods: We received advice through an advisory meeting of experts (professors of department of emergency medical technicians) and interested parties (Korean Association of Emergency Medical Technicians, officials of emergency medical technician training institutions) and referred to various reports published by governments, official institutions, and other trustworthy organizations. Also, we communicated with the related experts abroad (3 countries) on the phone or by email for surveys. Results: Compared to the abroad, it is necessary to categorize the standards and procedures of designating the emergency medical technician training institutions in Korea and improve the management of training institutions to train competent emergency medical technicians. Conclusion: It is necessary to designate and manage continuously the emergency medical technician-basic training programs for the systematic primary healthcare service.