• ETRI Journal
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• 제37권6호
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• pp.1108-1119
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• 2015

Multicast communication of mobile ad hoc networks is vulnerable to internal attacks due to its routing structure and high scalability of its participants. Though existing intrusion detection systems (IDSs) act smartly to defend against attack strategies, adversaries also accordingly update their attacking plans intelligently so as to intervene in successful defending schemes. In our work, we present a novel indirect internal stealthy attack on a tree-based multicast routing protocol. Such an indirect stealthy attack intelligently makes neighbor nodes drop their routing-layer unicast control packets instead of processing or forwarding them. The adversary targets the collision avoidance mechanism of the Medium Access Control (MAC) protocol to indirectly affect the routing layer process. Simulation results show the success of this attacking strategy over the existing "stealthy attack in wireless ad hoc networks: detection and countermeasure (SADEC)" detection system. We design a cross-layer automata-based stealthy attack on multicast routing protocols (SAMRP) attacker detection system to identify and isolate the proposed attacker. NS-2 simulation and analytical results show the efficient performance, against an indirect internal stealthy attack, of SAMRP over the existing SADEC and BLM attacker detection systems.

• Journal of Information Processing Systems
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• 제7권1호
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• pp.151-158
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• 2011

Bivium is a simplified version of Trivium, a hardware profile finalist of the eSTREAM project. Bivium has an internal state size of 177 bits and a key length of 80 bits. In this paper, a guess and determine attack on this cipher is introduced. In the proposed method, the best linear approximations for the updating functions are first defined. Then by using these calculated approximations, a system of linear equations is built. By guessing 30 bits of internal state, the system is solved and all the other 147 remaining bits are determined. The complexity of the attack is O ($2^{30}$), which is an improvement to the previous guess and determine attack with a complexity of order O($2^{52.3}$).

• 대한한방내과학회지
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• 제20권1호
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• pp.244-260
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• 1999

This study was to investigate diagnosis of shoulder pain on cerebrovascular attack patients and treatment effects by using physical treatment and orienatal diagnosis aparatus, as oriental diagnosis equipments, these were used thermography, maegzin and yangdorag machine. as physical treatment equipments, these were used Hot pack, TENS (Transcutaneous electrical nerve stimulation), ICT(Interferential current therapy) the results were followed 1. In Sex and Age distribution on cerebrovascular attack patients with shoulder pain, male(51.7%)had many than female(48.3%) and 60s were the top, next 70s 50s 40s. 2. In the reason of cerebrovascular attack and the type of motor paresis, cerebrovascular infarction(73.3%) had many than hemorrhage(26.7%) 3. In hospitalizied period of cerebrovascular attack patients with shoulder pain, the period from 11 to 60 days had almost occupied. 4. Oriental medical diagnositic propriety of shoulder pain by using maegzin and yangdorag machine were not recognized. 5. In measuring passive range of motion of pre and post treatment, improvement effect on Hot pack was not showed, but effects on TENS, ICT were showed. 6. In measuring temperature of painful shouler joint of pre and post treatment by using thermography, the effect of Hot pack was not recognized but the effects of TENS, ICT were recognized.

• 대한한방내과학회지
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• 제21권1호
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• pp.135-145
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• 2000

Objective : This study has been made to analysis of clinical type of vertigo prodromic Cerebral Vascular Disease in stroke patients who admitted to sangji oriental hospital department of circulatoty internal medicine in the period from July. 1999 to October 1999. Methods : A Questionaire was done after explanationin details to patients and agreement of patients. The inquire was done as follows. Sex and age, risk factor of stroke, type of stroke, existence of vertigo last three years before stroke attack, the beginning age of vertigo and period of prevalence, frequency, continuance time of vertigo, predilection season and time, factor of causing vertigo, accompanying symptoms of vertigo, severity of vertigo. Result and Conclusion : The existence of Rotation sense(Rotation group and non-Rotation group) and the type of Stroke is no difference significantly but the Rotation vertigo group and non-Rotation vertigo group is difference significantly in distribution. The sixties in age of vertigo attack, previous vertigo before 3 year Stroke attack, irregular in predilection season of vertigo, have a high frequency significantly in distribution and previous period of vertigo has no significantly difference in distribution. One or two per a month in frequency of vertigo, below 5 minute in continuance time of vertigo, irregular in predilection time of vertigo, stand up and sit down in causing vertigo position have a high frequency significantly in distribution.

• 대한한방내과학회지
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• 제39권2호
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• pp.154-158
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• 2018

Introduction: This case report assessed the effects of Korean medicine treatments on a chronic migraine patient who did not respond to triptan. Case Presentation: The patient received Korean medicine treatments, such as acupuncture, moxibustion, cupping, and herbal medication, during a hospitalization period. The effects of treatments were assessed with the Numerical Rating Scale (NRS) and migraine attack frequency. The intensity and attack frequency of migraines were significantly reduced after the complete treatment. Conclusions: For migraines, Korean medicine such as acupuncture and herbal medication could be an alternative to conventional therapy.

• 중소기업융합학회논문지
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• 제5권1호
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• pp.25-30
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• 2015

APT공격은 해커가 다양한 보안 위협을 만들어 특정 기업이나 조직의 네트워크에 지속적으로 가하는 공격을 뜻한다. 지능형 지속 공격이라 한다. 특정 조직 내부 직원의 PC를 장악한 뒤 그 PC를 통해 내부 서버나 데이터베이스에 접근한 뒤 기밀정보 등을 빼오거나 파괴한다. APT의 공격 방법은 제로데이와 루트킷 이렇게 크게 두 가지 공격이 있다. APT의 공격 과정은 침투, 검색, 수집, 유출 단계 4단계로 구분된다. 과정을 통하여 APT에 어떻게 대응할 수 있는지 두 가지 방안으로 정의하였다. 기술을 통한 악성코드 공격자의 공격 소요 시간을 지연시키는 방안과 공격에 대한 탐지 및 제거 할 수 있는 방안으로 나누어서 설명하였다.

• 정보보호학회논문지
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• 제21권2호
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• pp.101-110
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• 2011

최근 Application에 대한 공격을 통하여 네트워크와 데이터베이스에 대한 방어정책인 침입탐지 룰(rule)을 무력화시키고, 침해사고를 유발한다. 이러한 공격으로부터 내부 네트워크와 데이터베이스의 안전성을 확보하기 위한 통합보안에 관한 연구가 필요하다. 본 논문에서는 침입탐지 룰을 설정한 Application에 대한 공격을 차단하기 위한 통합보안 시스템 구축에 관한 연구이다. 네트워크 기반의 공격을 탐지하여 대응하고, 내부 Integration Security System을 Virtual clustering과 Load balancing 기법으로 공격을 분산시키며, Packet 모니터링과 분석을 통하여 공격 목적지 Packet에 대한 방어정책 설정, 공격 Packet 분석, 기록, 룰 업데이트를 한다. 또한 공격 유형별 방어정책을 설정하여 Virtual Machine 분할 정책을 통한 접근 트래픽 해소, 공격차단에 적용하는 Integration Security System을 제안하고 방어를 실험한다. 본 연구 결과는 외부 해커의 공격에 대한 통합보안 방어를 위한 현실적인 자료를 제공하게 될 것이다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권9호
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• pp.4548-4559
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• 2018

Conditional differential attack against NFSR-based cryptosystems proposed by Knellwolf et al. in Asiacrypt 2010 has been widely used for analyzing round-reduced Grain v1. In this paper, we present improved conditional differential attacks on Grain v1 based on a factorization simplification method, which makes it possible to obtain the expressions of internal states in more rounds and analyze the expressions more precisely. Following a condition-imposing strategy that saves more IV bits, Sarkar's distinguishing attack on Grain v1 of 106 rounds is improved to a key recovery attack. Moreover, we show new distinguishing attack and key recovery attack on Grain v1 of 107 rounds with lower complexity O($2^{34}$) and appreciable theoretical success probability 93.7%. Most importantly, our attacks can practically recover key expressions with higher success probability than theoretical results.

• 대한한방내과학회지
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• 제30권4호
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• pp.696-707
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• 2009

Objective : We designed this study to investigate differences between stroke reattack and stroke first attack group to establish fundamental data and prevent a secondary stroke. Methods : 826 subjects were recruited from the patients admitted to the department of internal medicine at Kyung Hee University Oriental Medical Center, Kyung Hee University East-West Neo Medical Center, Kyungwon University Incheon Oriental Medical Center, Kyungwon University Songpa Oriental Medical Center and Dongguk University Ilsan Oriental Medical Center from 1 April 2007 to 31 August 2009. We compared general characteristics, classification of diagnosis, subtypes of cerebral infarction, risk factors, Sasang constitution, diagnostic classifications between stroke reattck and stroke first attack groups. Results : 1. In general characteristics, age differed significantly between the reattck and first attack groups. 2. Classification of diagnosis differed significantly between reattck and first attack groups. 3. In risk factors, hypertension, diabetes mellitus, alcohol drinking, and stress were significantly different between reattck and first attack groups. 4. Diagnostic classifications were significantly different between reattck and first attack groups. Conclusion : To prevent recurrence of stroke, education on stroke risk factors associated with recurrence is needed. In addition, those who are diagnosed as Dampness-Phlegm need to be well-controlled.

• 전기전자학회논문지
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• 제23권4호
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• pp.1469-1472
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• 2019

자동차에 사용하는 CAN 버스는 노드에 주소를 부여하지 않기 때문에 여러 노드 중 하나가 해킹을 당하여 악의적인 데이터 프레임을 전송하여도 어느 노드가 해킹 당했는지 식별하기 어렵다. 하지만 이러한 CAN 버스의 내부 공격은 자동차의 안전에 큰 위협이 될 수 있으므로 CAN 버스의 물리 계층에서 신속하게 대처하여야 한다. 본 논문에서는 CAN 버스 상에서 악의적인 데이터 프레임이 감지되면 침입 감지 시스템이 내부 공격 노드의 에러 카운터를 증가시켜서 버스에서 분리시킴으로서 악의적인 공격을 방어하는 기법을 제안하였다. 제안한 기법을 탑재한 CAN 컨트롤러를 Verilog HDL을 이용하여 구현하였고, 이를 통해 제안한 기법이 CAN 버스의 악의적인 내부 공격을 방어할 수 있음을 확인하였다.