Diagnosis and management of pancreaticopleural fistula: Report of two cases

최도현,박지영,전태주,김영문,송두한,서영기,양경호 대한내과학회 2018 대한내과학회 추계학술대회 Vol.2018 No.1

그래프 데이터베이스 기반 악성코드 행위 탐지 기법

최도현,박중오,Choi, Do-Hyeon,Park, Jung-Oh 중소기업융합학회 2021 융합정보논문지 Vol.11 No.4

최근 악성코드 발생률은 약 수만 건이 넘는 추세로, 전부 탐지/대응하는 것은 불가능에 가깝다고 알려졌다. 본 연구는 새로운 악성코드 대응방법으로 그래프 데이터베이스 기반 다중행위 패턴 탐지 기법을 제안한다. 기존 동적 분석기법과는 다른 새로운 그래프 모델을 설계하고, 대표적인 악성코드 패턴(프로세스, PE, 레지스트리 등)의 그래프 연관관계를 분석하는 방법을 적용했다. 패턴 검증 결과 기본 악성 패턴에 대한 행위 탐지와 기존 분석이 어려웠던 변종 공격행위(5단계 이상)의 탐지를 확인했다. 또한, 성능 분석결과 5단계 이상의 복잡한 패턴에 대하여 관계형 데이터베이스 대비 약 9.84배 이상 성능이 향상되었음을 확인하였다. Recently, the incidence rate of malicious codes is over tens of thousands of cases, and it is known that it is almost impossible to detect/respond all of them. This study proposes a method for detecting multiple behavior patterns based on a graph database as a new method for dealing with malicious codes. Traditional dynamic analysis techniques and has applied a method to design and analyze graphs of representative associations malware pattern(process, PE, registry, etc.), another new graph model. As a result of the pattern verification, it was confirmed that the behavior of the basic malicious pattern was detected and the variant attack behavior(at least 5 steps), which was difficult to analyze in the past. In addition, as a result of the performance analysis, it was confirmed that the performance was improved by about 9.84 times or more compared to the relational database for complex patterns of 5 or more steps.

하악골 결손부의 골형성에 미치는 Bioplant® HTR(Hard Tissue Replacement)의 영향

최도현,유선열 전남대학교 치의학연구소 2001 구강과학 Vol.13 No.4

The present study was performed to investigate the effect of HTR® (Hard Tissue Replacement) on osteogenesis in the mandibular bone defects. Eight adult male white rabbits weighing 2.5 to 3.0 kg were used. Four bone defects (8 mm in diameter and 4 mm in depth) were made at the both mandibular body. In the control group, the right mesial bone defect was filled with blood clot and spontaneously healed. In the DFDB group, the right distal bone defect was filled with xenogenic demineralized freeze-dried bone. In the HTR® group, the left mesial bone defect was filled with HTR®. In the HTR®-membrane group, the left distal bone defect was filled with HTR® and covered with BioMesh® membrane. The rabbits were sacrified at 2, 4, 6 and 9 weeks after the operation and microscopic examination was performed. Results obtained were as follows: In the control and DFDB groups, inflammatory cells and the fibrous connective tissue existed and the bone growth was slower than HTR® group by 6 week, and there was intervention of the soft tissue at 9 week. In the HTR® group, bone trabeculi extended between the HTR® particles without intervention of inflammatory cells and the connective tissue at 4 and 6 weeks. In addition, extensive osseous ingrowth into the HTR® particles was observed at 9 week. Bone formation was more active in the HTR® group than the control and DFDB groups. There was not obvious difference in the bone healing rate between the HTR® and the HTR®-membrane group. These results suggest that the HTR® promotes osteogenesis in the bone defects and the HTR® group has no difference in comparison with the HTR®-BioMesh® membrane group in bone healing.

固體一液體 垂直流에서의 摩擦에 依한 壓損失

崔道賢 건국대학교 1974 學術誌 Vol.18 No.1

Equations showing the variation of frictional pressure drop across the smoothly fluidized bed by liquid as the fluid velocity were derived by combining the fixed bed pressure drop equation by Ergun with the empirical correlation by Richardson et al., relating the dependance of falling velocity of a particle in multiparticle system on the solid volumetric concentration. Some subsidiary equations, figures, and tables were also given.

하악골 결손부의 골형성에 미치는 Bioplant HTRⓡ의 영향

최도현,유선열,김옥준,허원실 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.1

The present study was performed to investigate the effect of HTR□ (Hard Tissue Replacement) on osteogenesis in the mandibular bone defects. Eight adult male white rabbits weighing 2.5 to 3.0kg were used. Four bone defects (8mm in diameter and 4mm in depth) were made at the both mandibular body. In the control group, the right mesial bone defect was filled with blood clot and spontaneously healed, In the DFDB group, the right distal bone defect was filled with xenogenic demineralized freeze-dried bone. In the HTR□ group, the left mesial bone defect was filled with HTR□. In the HTR□-membrane group, the left dis- tal bone defect was filled with HTR□ and covered with BioMesh membrane. The rabbits were sacrified at 2,4,6 and 9 weeks after the operation and microscopic examination was performed. Results obtained were as follows: In the control and DFDB groups, inflammatory cells and the fibrous connective tissue existed and the bone growth was slower than HTR□ group by 6 week, and there was intervention of the soft tissue at 9 week. In the HTR□ group, bone trabeculi extended between the HTR□ particles without intervention of inflammatory cells and the connective tissue at 4 and 6 weeks. In addition, extensive osseous ingrowth into the HTR□ particles was observed at 9 week. Bone formation was more active in the HTR□ group than the control and DFDB groups. There was not obvious difference in the bone healing rate between the HTR□ and the HTR□-membrane group. These results suggest that the HTR□ promotes osteogenesis in the bone defects and the HTR□ group has no difference in comparison with the HTR□-BioMesh□ membrane group in bone healing.

대민서비스 온라인 보안위협 분석 및 대응방안 연구

최도현,전문석,박중오 한국인터넷방송통신학회 2014 한국인터넷방송통신학회 논문지 Vol.14 No.5

전자정부 대민서비스는 과거부터 현재까지 공공기관 홈페이지가 다양해지고 서비스 수가 증가함에 따라, 전자민원 문서의 위·변조에 대한 가능성이 제기되는 등 전자민원 서비스 전반에 대한 보안에 대한 요구사항이 증가하고 있다. 기존 연구[1][2][3][4]는 전자정부 중 민원서비스(G4C)와 같은 하나의 서비스와 서비스 제공자 관점에서 보안위협과 대응방안을 제시하였다. 본 연구는 분석 범위를 확대하여 최근 대민서비스 제공 중인 289개 홈페이지를 대상으로 서비스 유형 별 적용되어 있는 보안기술을 분석하고 보안위협에 따른 대응방안을 제시하였다. 본 논문을 통해 대민서비스에 대한 실질적인 대응방안과 동시에 현재 해결해야 할 전자정부 대민서비스의 핵심적인 문제에 대하여 논의하고자 한다. As the number of public institution web sites and civil services based on electronic government has increased from the past until now, there is an increasing demand for security of the overall electronic civil services such as possibility for forgery and falsification of electronic documents. Existing studies[1][2][3][4] proposed security threats and response methods on an electronic government service (G4C) from the perspective of service provider. In this study, the scope of analysis was expanded to analyze security technology used for each service type on 289 web sites providing civil services and to present response methods on security threats. The aim of this paper is to discuss practical responses to civil services and core problems of civil services in electronic government that need to be resolved.

數學的 處理에 의한 Buffer Value의 計算

崔道賢 건국대학교 1975 工大硏究報 Vol.5 No.1

Determination of buffer value through mathematical process. Determination of buffer values for polybasic acids was mathenatically treated. The final equations derived indicated some difference in form from those by Van. Slyke except in the case of monobasic acid while only negligible errors would be caused with the latter for most of general cases where difference between the adjacent consecutive ionization constant values are bundredfold or more.

攪拌反應槽內 成分들의 滯留時間 및 濃度分布에 關하여

崔道賢 건국대학교 1974 공대학보 Vol.3 No.1

The retention time distribution of the liquid eactsnt and product, and the age distribution f the latter were mathmatically analyzed in he steadily operated, ideally mixing tank reactor, along with the retention time and the gas reactant concentration distriduttion of the dispersed phase.

M2M 환경의 디바이스 키 보호를 위한 암호 알고리즘 응용 기법

최도현,박중오 한국디지털정책학회 2015 디지털융복합연구 Vol.13 No.10

빅데이터 환경에서 기계학습 알고리즘 응용을 통한 보안 성향 분석 기법

최도현,박중오 한국디지털정책학회 2015 디지털융복합연구 Vol.13 No.9