• Journal of Electrical Engineering and Technology
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• 제10권2호
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• pp.465-473
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• 2015

The increasing need to improve transient security assessment of existing or forecasted operating conditions of networks by power system operators is major concern of the power system security monitoring problem at the Energy Management Systems. This paper proposes a preventive control of transient stability with generation rescheduling based on rotor trajectory index obtained using time domain simulations. This index may help power engineers in making operational decision and to obtain a generation configuration with better transient security dispatch. The effectiveness of the proposed methodology is demonstrated on IEEE 39-bus New England system for a three phase fault at different loading conditions with single and multiple line outage cases.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2016년도 제53차 동계학술대회논문집 24권1호
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• pp.311-314
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• 2016

지난 5년간 대표적인 산업제어시스템(Industrial Control System)인 국내 원자력 발전소에 대한 해킹 시도는 총 1,843회로 사이버공격에 대한 위험은 날로 높아지고 있다. 이러한 공격은 사이버전, 테러, 사이버범죄자들에 의해 실행되고 있다. 이러한 위험을 통제하기 위해서는 산업제어시스템이 일반적인 IT시스템과 다른 운영체제, 네트워크 등 시스템 환경을 고려하여야 한다. 본 논문에서는 기존의 IT보안 대책과 산업제어시스템 보안 대책을 비교 분석하고, 국내외에서 발생하고 있는 산업제어시스템에 대한 공격 사례를 비교 분석하여 산업제어시스템 인프라에서 고려하고 통제해야 할 정보보호 요소들을 제언한다.

• 한국산업정보학회논문지
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• 제4권4호
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• pp.137-142
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• 1999

본 논문은 리눅스 서버 환경에서 여러 분야의 업무를 운영하려고 할 때에 발생되는 보안 문제를 해결하기 위해서 역할기반 접근제어(Role-Based Access Control : RBAC) 기법을 이용하여, 리눅스 환경에서 운영 가능한 RBAC＿Linux 보안 시스템을 설계하였다. 본 논문에서 RBAC_Linux는 RBAC 기법을 리눅스 환경에 적용하여 설계되었으며, 적용한 RBAC 모델로는 Sandhu 등이 제안한 RBAC96모델을 이용한다. 따라서 리눅스 서버 시스템에 설계 제안된 RBAC_Linux 보안 시스템을 이용하면 서버의 소스코드를 수정없이 구현 가능하여, 이식성이 높으며, 보안 관리가 단순하고 용이하다는 장점을 갖는다.

• 한국안전학회지
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• 제12권3호
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• pp.67-75
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• 1997

This paper presents a study on the application of Asynchronous Team(A-Team) theory for QVC(Reactive power control) and security assessment in a power system. Reactive power control problem is the one of optimally establishing voltage level given reactive power sources, which is very important problem to supply the demand without interruption and needs methods to alleviate a bus voltage limit violation more quickly. It can be formulated as a mixed-integer linear programming(MILP) problem without deteriorating of solution accuracy to a certain extent. The security assessment is to estimate the relative robustness of the system and deterministic approach based on AC load flow calculations is adopted to assess it, especially voltage security. A distance measure, as a measurement for voltage security, is introduced. In order to analyze the above two problem, reactive power control and static security assessment, In an integrated fashion, a new organizational structure, called an A-team, is adopted. An A-team is well-suited to the development of computer-based, multi-agent systems for operation of large-scaled power systems. In order to verify the usefulness of the suggested scheme herein, modified IEEE 30 bus system is employed as a sample system. The results of a case study are also presented.

• 한국정보통신학회논문지
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• 제16권9호
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• pp.1955-1962
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• 2012

최근 정보보안의 흐름은 사용자 중심으로 변화가 되고 있다. 이는 사용자가 인터넷을 하는 동안 정상적 및 비정상적으로 유입되는 유해한 파일에 의한 보안사고가 대부분이라는 의미이다. 따라서 본 논문에서는 DNS에 대한 신뢰성을 향상시키고 DNS를 이용한 시스템 제어를 통해 침해사고를 사전에 예방할 수 있는 보안 시스템을 설계하고자 한다. 즉 사용자 중심의 정보보안 시스템으로 사용자 컴퓨터에 감염된 유해 파일이 임의로 사이트를 접속하는 행위에 대하여 차단할 수 있는 방법을 제안하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.163-165
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• 2007

Recently, the security requirements of the embedded system which were not considered when the embedded system is independently deployed are being increased because the embedded system is connected to an internet. The connection to the internet of embedded system is the meaning that it is exposed to the various kinds of external attack and can be a victim to these attacks in anytime. Particularly, it is trend that the user-related information is stored into the personal terminals and/or electrical appliances such as PDA, home gateway for home network, settop boxes and so on. So it is needed the security mechanism which protects the user information from the malicious accesses. Accordingly, the coverage of the system security is being expanded from the general server to the embedded system. And it is not enough that the embedded system supports only its inherent functions and it becomes the essential element to provide the security function to the embedded system. This paper applies the RBAC(role-based access control) function to the embedded linux OS and tries to strengthen the security of the embedded linux OS. RBAC is implemented as a loadable kernel module with LSM(Linux Security Module) security framework for user's flexibility.

• International Journal of Computer Science & Network Security
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• 제22권2호
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• pp.341-347
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• 2022

This research is designed to help and offer hold up to complete the requirements of aged and disable in a home. The control approach and the tone approach are used to manage the house appliances. The major organize system implementation in technology of wireless to offer distant contact from a phone Internet Protocol connectivity for access and calculating strategy and appliance remotely. The planned system no need a committed server PC with value of parallel systems and offers a new communication-protocol to observe and control a house environment with more than just the switch functionality. To express the possibility and efficiency of this system, devices like as lights switches, power plugs, and motion-sensors have been included with the planned home control system and supply more security manage on the control with low electrical energy activate method. The rank of switches is corresponding in all this control system whereby all user interfaces indicate the real time existing status. This system planned to manage electrical-appliances and devices in house with reasonably low cost of design, user friendly interface, easily install and provide high security. Research community generally specified that the network "Reconnaissance Attacks" in IPv6 are usually impossible due to they will take huge challenge to carry out address scanning of 264 hosts in an IPv6 subnet."It being deployed of IPv6 shows that it definitely enhances security and undermines the probability". This research of the IPv6 addressing-strategies at present utilizes and planned a new strategy and move toward to "mitigate reconnaissance attacks".

• Nuclear Engineering and Technology
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• 제55권6호
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• pp.2034-2046
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• 2023

Industrial control systems in nuclear facilities are facing increasing cyber threats due to the widespread use of information and communication equipment. To implement cyber security programs effectively through the RG 5.71, it is necessary to quantitatively assess cyber risks. However, this can be challenging due to limited historical data on threats and customized Critical Digital Assets (CDAs) in nuclear facilities. Previous works have focused on identifying data flows, the assets where the data is stored and processed, which means that the methods are heavily biased towards information security concerns. Additionally, in nuclear facilities, cyber threats need to be analyzed from a safety perspective. In this study, we use the system theoretic process analysis to identify system-level threat scenarios that could violate safety constraints. Instead of quantifying the likelihood of exploiting vulnerabilities, we quantify Security Control Measures (SCMs) against the identified threat scenarios. We classify the system and CDAs into four consequence-based classes, as presented in NEI 13-10, to analyze the adversary impact on CDAs. This allows for the ranking of identified threat scenarios according to the quantified SCMs. The proposed framework enables stakeholders to more effectively and accurately rank cyber risks, as well as establish security and response strategies.

• 디지털산업정보학회논문지
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• 제7권1호
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• pp.41-49
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• 2011

We designed a security improved document DRM for protecting document based military information which is transmitted in the military information system environment. The user should be could not access document which not related to his/her role and duty, and must view the only document appropriate for his/her role and security level according to the security level of document. We improved the security of document DRM by adding to the access control module in DRM server. Our system allows operation mode authorizations for the document, considering the user's role & security level and the security level of document. And it prevents indiscriminate access to the document and damage the confidentiality and integrity of information.

• 한국전자통신학회논문지
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• 제9권1호
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• pp.137-142
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• 2014

산업제어시스템(Industrial Control System)은 전력, 가스, 수도, 하수, 오일 및 교통시스템과 같은 국가주요기반시설 및 산업분야에서 원거리에 산재된 시스템의 효과적인 원격모니터링 및 제어를 위해 필수적으로 사용되는 컴퓨터 기반의 시스템을 말한다. 고도로 발전된 IT 및 네트워크 관련 기술들이 산업제어시스템에 적용되어 효율성을 높이는 장점이 있지만, 일반적인 IT 환경에서의 각종 정보시스템이 가지는 사이버보안 취약성 및 사고의 가능성이 증대되는 단점을 가지게 되었다. 산업제어시스템에서 통상적으로 발견되는 취약점은 우선순위, 발생빈도 및 영향의 심각성들과는 무관하게 정책 및 절차, 플랫폼 및 네트워크 등으로 분류된다. 이러한 취약점들은 첫째, 패스워드의 강제 사용등과 같은 보안 정책 및 절차를 적용함으로서 취약점을 경감 시킬 수 있다. 둘째로, 운영체제 및 응용프로그램의 패치 적용, 물리적인 접근제어, 보안프로그램 사용등과 같은 다양한 보안통제를 적용함으로서 취약점을 경감 및 완화 시킬 수 있다. 셋째로, 심층방호개념의 네트워크 설계, 네트워크 통신의 암호화, 네트워크 트래픽 제한, 네트워크 장비에 대한 물리적 접근제어 방법 등과 같은 다양한 보안통제를 적용함으로서 취약점을 제거하거나 완화 시킬 수 있다.