• ETRI Journal
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• 제42권6호
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• pp.886-898
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• 2020

Unusual data patterns or outliers can be generated because of human errors, incorrect measurements, or malicious activities. Detecting outliers is a difficult task that requires complex ensembles. An ideal outlier detection ensemble should consider the strengths of individual base detectors while carefully combining their outputs to create a strong overall ensemble and achieve unbiased accuracy with minimal variance. Selecting and combining the outputs of dissimilar base learners is a challenging task. This paper proposes a model that utilizes heterogeneous base learners. It adaptively boosts the outcomes of preceding learners in the first phase by assigning weights and identifying high-performing learners based on their local domains, and then carefully fuses their outcomes in the second phase to improve overall accuracy. Experimental results from 10 benchmark datasets are used to train and test the proposed model. To investigate its accuracy in terms of separating outliers from inliers, the proposed model is tested and evaluated using accuracy metrics. The analyzed data are presented as crosstabs and percentages, followed by a descriptive method for synthesis and interpretation.

• Animal cells and systems
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• 제1권3호
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• pp.429-434
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• 1997

A new genus with a new species of poecilostomatoid copepod, Polyankylis orientalis, is described based on a pair of specimens collected from a tide pool on muddy shore in Korea. It represents a new family of the lichomolgoid complex with the following distinguishing characters: (1) 6-segmented antennule (resulted from the fusion of the third and fourth segments) with additional aesthetascs in male, (2) hook on mediodistal corner of antennal coxobasis (first segment), (3) proximal and distal scales on the outer margin of mandible present, (4) main axis of mandibular gnathobase short and lacking notches at the base of mandibular lash, and (5) inner margin of mandibular lash with denticulate processes. Additionally, maxillar syncoxa carries a large, pointed process on ventral surface, legs 1-4 do not show sexua1 dimorphism, and leg 4 is uniramous with 1-segmented exopod. A detailed discussion is given of its affinities with the ten existing families of the lichomolgoid complex.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권8호
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• pp.357-368
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• 2013

우리 사회는 광대역 ICT 인프라의 확충과 스마트 디바이스, 클라우드 서비스 및 소셜 미디어 서비스의 활성화로 인해 언제 어디서나 다양한 지식의 공유 / 관리 / 제어 / 창조가 가능한 혼합현실 환경의 상시 연결사회로 진화하고 있고 이로 인해 사이버 위협이 점차 증가하고 있는 상황이다. 향후 사회는 물리 및 논리공간의 융합, 스마트 객체의 유기적 연결, 상시연결 사회의 보편화로 인하여 사이버 위협에 대한 효과적 대응을 하지 못하는 경우에 더욱 복잡하고 미묘한 문제를 야기할 수 있어 APT와 같은 고도화된 사이버 위협에 대한 새로운 접근방법과 대응 체계에 관한 연구가 요구된다. 본 논문에서는 향후 다양한 미래서비스 환경 변화와 상시 연결사회의 보편화에 따른 새로운 유형의 사이버 위협에 능동적으로 대응하기 위한 기반으로써 국가 보안 Knowledge-Base 구축 전략을 제시한다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.632-638
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• 2002

Electron beam (EB) and Gas tungsten arc (TIG) welds were performed on 12.7 mm thick Ti-6Al-4V plate (ASTM Titanium Grade 5). Charpy-V toughness and hardness, as well as, microstructure of the welds and penetration from the macrostructure were studied. It appears that by EB welding rather smaller $\beta$-grains than with TIG welding can be obtained. Next to the fusion line the $\beta$-grain size in the HAZ was 50 ${\mu}{\textrm}{m}$l while in the weld metal it was 150 ${\mu}{\textrm}{m}$. Charpy-V toughness of the EB weld metal was equal or even better to that of base metal, which shows that the $\alpha$-martensite per se is not particularly brittle if only the grain size is fine enough. This is similar to behavior of low carbon martensite in steel. The grain size was studied with light optical and scanning electron (SEM) microscopes. Thus for products, for products which can be manufactured automatically with very narrow fit, the EB welding of Ti-6Al-4V appears to yield satisfactory toughness without any complex post weld heat treatment. ill this study as in earlier studies the TIG welds gave lower toughness than that of the base material due to the higher heat input and slower cooling as compared to EB welding.

• 한국지능시스템학회논문지
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• 제24권6호
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• pp.597-602
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• 2014

본 논문은 대학의 복도와 같은 넓고 복잡한 환경에서 레이저 스캐너와 이미지 센서와 같은 다중센서 데이터 융합을 이용한 복수의 사람들에 대한 동작 인식 및 패턴 분석을 소개하였다. 제안한 방법의 인식 시스템은 첫째, 인물 추적을 위한 전 처리 기능과 둘째 이동궤적 특징, 보행특징, 이미지 특징, 환경(글로벌) 특징을 요구하는 특징부 추출에 대한 이론적 근거를 제시하였다. 최적의 영상을 기반으로 한 복잡환경 내에서의 복수의 사람들을 인식하고 움직임에 대한 패턴은 HMM과 SVM을 통한 학습 및 식별을 수행하였다. 학습 및 식별에서는 HMM을 이용한 이동 경로의 추정과 SVM을 이용한 비정상 보행 검색의 실례를 제시하였다. 또한 제안 방법을 검증하기 위하여 대학교의 복도에서 실시한 실험결과를 통해 타당성을 검증하였다.

• 한국지능시스템학회논문지
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• 제21권3호
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• pp.307-316
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• 2011

대부분의 해양 사고는 인적 요인에 의해 발생하며, 항행 전문가들은 그 문제의 해결을 위해인적 요인의 영향을 받지 않는 항행 지원 시스템을 요구하였다. 항행을 지원하기 위한 인공지능 기술 중에서 전문가 시스템은 전문가의 지식이나 경험들을 이용한 지식베이스와 그 추론 엔진의 구현을 통해 기계가 해당 분야의 전문가 역할을 대신할 수 있는 중요한 기법이다. 현실세계에서 복잡한 상황에 대한 정확한 판단을 하기 위해서는 여러 분야의 전문가에 의한 종합적인 판단이 필요하며, 특히, 그러한 판단은 여러 위험요소가 잠재되어 있는 항행상황에서 더욱 중요하다. 이 논문에서는 블랙보드 시스템을 이용하여 다양한 전문가 시스템으로부터 얻은 항행 안전 지식의 융합 방법을 제안하고, 테스트 시스템을 설계 및 구현하여 제안하는 방법의 타당성을 보인다.

• Archives of Plastic Surgery
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• 제33권2호
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• pp.237-240
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• 2006

The simultaneous correction of the hypertelorism and exophthalmos combined with craniosynostosis is very rarely performed operative procedures in the world. The craniosynostosis is the congenital anomaly that designates premature fusion of one or more sutures in either cranial vault or cranial base. Hypertelorism is not a distinct clinical syndrome in itself, but is a physical finding secondary to facial and cranial maldevelopment and it is defined as a increase in the distance between the medial orbital walls. Exophthalmos can occur following the decrease in the size of the orbit in patients with developmental skeletal disorders such as craniofacial synostosis. The authors experienced 9-year-old male patient, who has complex cranio-facial abnormality. The craniosynostosis was oxycephaly type and primary fronto-orbital advancement surgery had been performed in other hospital. The abnormal cranial vault combined with hypertelorism and exophthalmos due to maldeveloped both orbital walls. Surgical correction was obtained by various cranio-fronto-orbital remodeling technique such as calvarial bone craniotomy, fronto-orbital advancement, paramedian resection, medial canthopexy, Tessier-Wolfe three wall orbital expansions. We achieved a quite satisfactory result both functionally and aesthetically in a complex cranio-facial deformity patient by combination and modification of previously developed various cranio-facial plasty technique and hereby report the case with brief discussion and review of literature.

• 한국안전학회지
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• 제21권5호
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• pp.103-111
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• 2006

The purpose of this study was to analyse the relationships between cognitive abilities and driving characteristics of elderly drivers. Driving characteristics of elderly and younger drivers who were driving a fixed base driving simulator vehicle were examined. Participants consisted of 12 drivers over age 65 (the 'older' group) and 12 drivers between the ages of 25 and 55 (the "younger" group). As indices of cognitive ability, critical flicker fusion frequency (CFF) tests and cognitive reaction tests were given before the driving task. CFF was also tested after the simulated driving task for both groups. Cognitive reaction tests, which were composed of speed estimation tests, multiple choice reaction tests and obstacle avoidance tests, were developed by the Korean Road Traffic Safety Authority in 2003. CFF values between the two groups exhibited significant differences both before and after the task, with a p-value less than 0.01 and a t-value of -3.01 before the test and a p-value less than 0.031 and a t-value of -2.35 after the test. Older drivers' CFF values were lower than those of the younger. However, there was no difference in older or younger driver CFF values before and after the task within the same group. Except for the multiple choice reaction test, there was no difference in cognitive reaction test results between the two groups. The elderly drivers made more errors though they did not differ from the younger drivers in reaction times. At the simulated driving task the reaction time of the elderly driver was longer than that of the younger; however, the driving speed of the elderly was lower and the number of collisions greater. There was a positive correlation (r=.496) between the number of errors in the multiple choice reaction test and the number of collisions in the driving task. Therefore, it was identified that critical attributes contributing to automobile crashes involving elderly drivers included cognitive difficulty in judging and responding to complex situations.

• 대한금속재료학회지
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• 제49권12호
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• pp.967-976
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• 2011

Conventional fracture tests of resistance spot welds have been performed without consideration of the paint baking process in the automobile manufacturing line. The aim of this paper is to investigate the effect of the paint baking process on load carrying capacity and fracture mode for resistance spot welded 590 dual phase (DP), 780DP, 980DP, 590 transformation in duced plasticity (TRIP), 780TRIP and 1180 complex phase (CP) steels. With paint baking after resistance spot welding, the l-shape tensile test (LTT) and nano-indentation test were conducted on the as-welded and paint baked samples. Paint baking increased the load-carrying capacity of the resistance spot welded samples and improved the fracture appearance from partial interfacial fracture (PIF) to button fracture (BF). Improvement in fracture appearance after LTT is observed on weldments of 780 MPa grade TRIP steels, especially in the low welding current range with paint baking conditions. The higher carbon contents (or carbon equivalent) are attributed to the low weldability of the resistance spot welding of high strength steels. Improvement of the fracture mode and load carrying ability has been achieved with ferrite hardening and carbide formation during the paint baking process. The average nano-indentation hardness profile for each weld zone shows hardening of the base metal and softening of the heat affected zone (HAZ) and the weld metal, which proves that microstructural changes occur during low temperature heat treatment.

• 디지털융복합연구
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• 제17권2호
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• pp.31-36
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• 2019

최근 세계경제는 4차 산업혁명이라는 시대의 흐름에 따라 서로 다른 기술 산업 간 융 복합이 활성화되고 새로운 기술이 빠르게 창출되고 있다. 우리나라도 4차 산업혁명에 대응하고 글로벌 경쟁력을 확보하기 위하여 신기술 신서비스 기반의 혁신기술을 육성하고 있으나, 각종 규제로 인하여 신기술 신서비스에 대한 진입이 어려운 실정이다. 이에 정부는 신기술 신서비스를 활용한 혁신사업이 규제의 제약 없이 실험 실증하고 사업화 할 수 있도록 규제샌드박스(Sandbox)가 적용되는 규제자유특구도입을 추진하고 있다.. 본 연구는 지역특화발전특구와 새로이 도입되는 규제자유특구를 비교 연구함으로써, 전국에 획일적으로 적용되는 규제만을 완화하는 지역특화발전특구의 한계를 고찰하고, 규제자유특구가 신기술 기반의 실증 테스트 베드로 육성할 방향과 지역의 혁신성장 거점으로 성장할 방안을 제시하고자 한다.