• Journal of Preventive Medicine and Public Health
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• 제10권1호
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• pp.118-124
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• 1977

The features of crimes, their causes and backgrounds of 70 army delinquents, comparing with the controls, were studied from Nov. 1st, 1976 to Nov. 20, 1976 The results were as follows: 1. Most of the delinquents were from the adverse circumstances i. e. low education level, poor economic status, farmers and had got married. 2. The majority of the delinquents occurred within the first 2 years of the enlistment. 3. The rate of the parent-loss of the criminals was definitely higher than that of the controls. (48.6%) 4. Escapers from military service were over the half of them, and violence, steal and embezzlement were followed. The motivations of the escape from the military service was mostly domestic problem and illness; but a lot of the criminals also escaped for amusement and pleasure. 5. The prognosis of them was relatively favorable and constructive.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 제5회 박판성형 SYMPOSIUM
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• pp.34-39
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• 2006

An automated surface-strain measurement system, named ASIAS, was developed by using the image processing and stereo vision techniques in the previous studies by the corresponding author and his coworkers. This system has been upgraded mainly to improve the accuracy through image enhancement, sub-pixel measurement, surface smoothing, etc., since the first version was released. The present study has still more improved the convenience of users as well as the accuracy of measurement by processing high resolution images 8 mega pixels or more which can be easily obtained from a portable digital steal camera. It is proved that high resolution image processing greatly decreases the measurement error and gives strain data without considerable deterioration of accuracy even when the deformed grids to be measured and the master grids for camera calibration are captured together in the same image, making the whole process of strain measurement much simpler.

• 한국해양공학회지
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• 제19권2호
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• pp.1-11
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• 2005

In the present paper, the hydrodynamic properties of a Rahmen type flexible porous breakwater with dual fixed pontoon system interacting with obliquely or normally incident small amplitude waves are numerically investigated. This system is composed of dual vertical porous membranes hinged at the side edges of dual fixed pontoons, and a submerged horizontal membrane that both ends are hinged at the steel frames mounted pontoons. The dual vertical membranes are extended downward and hinged at bottom steal frame fixed into seabed. The wave blocking and dissipation mechanism and its effects of permeability, Rahmen type membrane and pontoon geometry, pretensions on membranes, relative dimensionless wave number, and incident wave headings are thoroughly examined.

• Journal of Chest Surgery
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• 제22권2호
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• pp.330-336
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• 1989

The patient was 47-year-old male who had suffered from aphasia and hemiplegia of the right side, but mental state was alert. On physical examination, BP was 130/80 mmHg in the right arm, but not checked in the left arm. The pulses of the left common carotid, brachial, and radial arteries were not palpable. The pulses of the right femoral, popliteal, and dorsalis pedis arteries were weakly palpable. Brain CT Scan revealed cerebral infarction of the left hemisphere. Aortogram showed occlusion of the left common carotid, and the right internal carotid and common iliac arteries. Subclavian steal phenomena were observed in the delayed aortogram. Double extra-anatomic bypasses; Axillo-Axillar bypass and Femora-Femoral bypass, were performed in the local anesthesia at two stages, because of risk of major operation under general anesthesia. Postoperatively, all pulses except for pulse of the left common carotid artery were equally palpable. On discharge, the hemiplegia of the right side was improved and able to walk with assistance.

• Journal of Information Processing Systems
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• 제16권5호
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• pp.1034-1047
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• 2020

The personal authentication technique is an essential tool in this complex and modern digital information society. Traditionally, the most general mechanism of personal authentication was using alphanumeric passwords. However, passwords that are hard to guess or to break, are often hard to remember. There are demands for a technology capable of replacing the text-based password system. Graphical passwords can be an alternative, but it is vulnerable to shoulder-surfing attacks. This paper looks through a number of recently developed graphical password systems and introduces a personal authentication system using a machine learning technique with electroencephalography (EEG) signals as a new type of personal authentication system which is easier for a person to use and more difficult for others to steal than other preexisting authentication systems.

• 기술발표회
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• 통권2006호
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• pp.66-72
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• 2006

The ground anchoring has been utilized over 40 years. It is growing the application of the removal ground anchor with tension force for holding earth retaining constructions in the city. It transmits tension stress of prestressed steel wire through grouting to fixed the ground that is of great advantage adjacent ground stability. Nowadays, we can find the compression dispersion anchor on many site. But, it has some problems in behavior of anchors because of impossible to tense p.c strand uniformly under the existing equipment due to different length of p c strand. Hence, motive of this research was to study the application of the newly developed tension system, that analyze and compare with the current anchoring method build on the data of in-site test and laboratory test. As a result, in case of auto back tension system, it became clear that tension pressure was equally distributed among the steal wires but the existing tension system showed sign of instability by indicating stress deflection of about 30% compare with design load. This can cause an ultimate failure of the concentrated p.c strand and a shear failure of ground.

• 정보보호학회논문지
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• 제21권1호
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• pp.187-199
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• 2011

모바일뱅킹에서 사용자인증과 거래승인을 보호하는 것은 매우 중요하다. 스마트폰에 설치된 악성 프로그램은 사용자가 입력하는 비밀을 얻어내거나 거래내용을 조작하여 사용자에게 승인하도록 유도할 수도 있다. 이 논문에서는 사용자의 비밀과 거래승인을 보호하기 위한 연구들의 보안성과 편의성을 분석하고, 이를 바탕으로 사용자의 비밀을 보호하고 문서의 내용을 조작하는 공격에 대응하는 방법을 제안한다.

• Journal of Multimedia Information System
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• 제9권2호
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• pp.103-112
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• 2022

Background: A presentation attack places the printed image or displayed video at the front of the sensor to deceive the biometric recognition system. Usually, presentation attackers steal a genuine user's biometric image and use it for presentation attack. In recent years, reconstruction attack and adversarial attack can generate high-quality fake images, and have high attack success rates. However, their attack rates degrade remarkably after image shooting. Methods: In order to comprehensively analyze the threat of presentation attack to palmprint recognition system, this paper makes six palmprint presentation attack datasets. The datasets were tested on texture coding-based recognition methods and deep learning-based recognition methods. Results and conclusion: The experimental results show that the presentation attack caused by the leakage of the original image has a high success rate and a great threat; while the success rates of reconstruction attack and adversarial attack decrease significantly.

• International Journal of Computer Science & Network Security
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• 제23권10호
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• pp.157-163
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• 2023

The attack technique targeting end-users through phishing URLs is very dangerous nowadays. With this technique, attackers could steal user data or take control of the system, etc. Therefore, early detecting phishing URLs is essential. In this paper, we propose a method to detect phishing URLs based on supervised learning algorithms and abnormal behaviors from URLs. Finally, based on the research results, we build a framework for detecting phishing URLs through end-users. The novelty and advantage of our proposed method are that abnormal behaviors are extracted based on URLs which are monitored and collected directly from attack campaigns instead of using inefficient old datasets.

• 한국콘텐츠학회논문지
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• 제16권8호
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• pp.90-96
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• 2016

우리나라는 스마트폰 보급률이 83%로 성인인구 4,000만명 중 3,390만 명이 사용하고 있으며, 이러한 사용자 대부분이 공인인증서에 대한 안전성 문제가 지속적으로 제기됨에도 불구하고 공인인증서를 사용하고 있다. 이러한 안전성의 문제로 인해 SMS를 이용한 휴대폰 소유자 인증기술, 생체인증을 통한 본인 인증기술 등 다양한 인증기술들이 제안되고 있다. 그러나 아직까지도 공인인증서를 대체할 만한 안전하고 믿을 만한 인증체계가 제시되지 않고 있다. 또한 사용자가 제일 많은 공인인증서와 개인키에 대한 탈취 시도가 지속적으로 발생하고 있다. 이러한 이유로 인해 보안전문가들은 공인인증서와 개인키를 USB 플래시 드라이브, 보안토큰, 스마트폰에 저장하도록 권고한다. 하지만 보안전문가가 추천하는 외부 저장매체 중 스마트폰은 앱을 통해 악성코드가 쉽게 전파되고, 악성코드에 의한 인증서나 개인키 파일을 외부로 유출이 가능하다. 해커가 유출한 인증서와 개인키 파일과 함께 개인키 암호용 패스워드만 알아내면 언제든지 정당한 사용자로 위장할 수 있다. 이에 본 논문에서는 스마트폰의 고유정보와 사용자 패스워드를 조합하여 스마트폰에 저장된 개인키 파일의 안전한 관리 방안을 제안한다. 제안 방안을 활용하게 되면 스마트폰에 저장된 개인키와 인증서 파일이 공격자에게 탈취되더라도 스마트폰의 고유 정보를 획득할 수 없으므로 암호화된 개인키의 재사용이 불가능하다. 따라서 제안 방안을 공인인증 체계에 활용한다면 스마트폰 사용자에게 현재보다 훨씬 향상된 보안 서비스를 제공할 수 있을 것으로 예상한다.