• Journal of Information Processing Systems
• /
• 제16권1호
• /
• pp.42-48
• /
• 2020

This paper proposes an operating system architecture for unmanned aerial vehicle (UAV), which is secure against root exploit, resilient to connection loss resulting in the control loss, and able to utilize common applications used in Linux. The Linux-based UAVs are exposed to root exploit. On the other hand, the microkernel-based UAVs are not able to use the common applications utilized in Linux, even though which is secure against root exploit. For this reason, the proposed architecture uses a virtualized microkernel on the Linux operating system to isolate communication roles and prevent root exploit. As a result, the suggested Operating system is secure against root exploit and is able to utilize the common applications at the same time.

• 정보처리학회논문지A
• /
• 제15A권1호
• /
• pp.45-52
• /
• 2008

본 논문에서는 심볼릭 링크 공격에 취약한 코드를 정의하고 프로그램 분석 기법을 사용하여 이를 검출하는 방법을 제안한다. 심볼릭 링크 공격을 해결하기 위한 기존의 방법들은 심볼릭 링크 공격을 방어하기 위한 기법들로써 임시 파일에 대한 접근 시 공격이 이루어졌는지에 대한 적절한 검사가 이루어져야 하나, 이를 간과할 경우 공격의 위험에 노출되게 된다. 본 논문에서 제안하는 방법은 심볼릭 링크 공격에 취약한 부분을 자동으로 모두 검출함으로써 프로그래머가 심볼릭 링크 공격을 안전하게 방어할 수 있도록 한다. 제안하는 방법은 취약점 분석을 위해서 기존의 타입 시스템에 새로운 타입 한정자를 추가하고, 추가된 타입 한정자를 고려한 타입 검사를 통해서 심볼릭 링크 공격의 취약점을 식별한다. 제안하는 방법은 자동으로 심볼릭 링크 공격의 취약점을 모두 검출할 수 있기 때문에, 프로그래머가 취약한 것으로 식별된 코드에 대해서만 기존의 방어 기법을 적용하도록 함으로써 프로그램을 전반적으로 검토하거나 수정해야 하는 부담을 줄여준다는 장점을 가진다. 제안하는 방법을 널리 알려진 실용적인 프로그램을 대상으로 실험해 본 결과 전체 fopen() 함수 중 일부만 심볼릭 링크 공격에 취약한 것으로 분석되었으며, 이는 제안한 방법이 프로그래머의 부담을 줄이는데 유용함을 보여준다.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2016년도 춘계학술대회
• /
• pp.755-758
• /
• 2016

본 논문에서는 바이너리 프로그램에서 함수가 호출될 시 바이너리 내에서 어떠한 방법으로 함수를 호출하는지 설명한다. 그리고 그 함수를 호출할시 필요한 요소들과 C언어 파일의 동적링크 컴파일 과정과 그 요소들을 이어주는 '링커'라는 개념을 설명하고, 정적링크와 동적링크를 차이점을 비교 분석한다. 또한 동적 링크를 활용하여 취약점을 공격하는 Return To Dynamic Linker에 대해 간략히 서술하며 테스트바이너리에 시험해본다.

• 대한임베디드공학회논문지
• /
• 제6권6호
• /
• pp.345-359
• /
• 2011

In high performance embedded systems, the use of multiple on-chip memories is an essential architectural feature for exploiting inherent parallelism in multimedia applications. This feature allows multiple data accesses to be executed in parallel. However, it remains difficult to effectively exploit of multiple on-chip memories. The successful use of this architecture strongly depends on how to efficiently detect and exploit memory parallelism in target applications. In this paper, we propose a technique based on a linear array access descriptor [1], which is generated from profiled data, to detect and exploit memory parallelism. The proposed technique tackles an array reorganization problem to maximize memory parallelism in multimedia applications. We present preliminary experiments applying the proposed technique onto a representative coarse grained reconfigurable array processor (CGRA) with multimedia kernel codes. Our experimental results demonstrate that our technique optimizes data placement by putting independent data on separate storage. The results exhibit 9.8% higher performance on average compared to the existing method.

• 정보보호학회논문지
• /
• 제19권4호
• /
• pp.29-39
• /
• 2009

통신망을 통하여 자동적으로 확산되는 악성 프로그램인 웜에 대응하기 위하여, 웜 관련 패킷들을 분석하여 시그니처를 생성하여 웹을 탐지하는 방법들이 많이 사용되고 있다. 그러나 이런 시그니처-기반 탐지 기법을 회피하기 위하여, 변형된 폴리모픽 형태의 공격 코드 사용이 점차 증가하고 있다. 본 논문에서는 폴리모픽 공격 코드의 복호화 루틴을 탐지하기 위한 새로운 정적 분석 방법을 제안한다. 제안된 방법은 통신망 플로에서 폴리모픽 공격 코드에 함께 포함되어 암호화된 원본 코드를 복호화하는 역할을 수행하는 코드 루틴을 탐지한다. 실험 결과를 통하여 제안된 방법이 정적 분석 방지 기법들이 사용된 폴리모팍 코드들도 탐지할 수 있는 것을 보여준다. 또한 처리 성능에서 에뮬레이션 기반 분석 방법보다 효율적인 것으로 나타났다.

• ETRI Journal
• /
• 제37권1호
• /
• pp.147-156
• /
• 2015

A typical solid-state drive contains several independent channels that can be operated in parallel. To exploit this channel-level parallelism, a variety of works proposed to split consecutive write sequences into small segments and schedule them to different channels. This scheme exploits the parallelism but breaks the spatial locality of write traffic; thus, it is able to significantly degrade the efficiency of garbage collection. This paper proposes a channel-aware write reordering (CAWR) mechanism to schedule write requests to different channels more intelligently. The novel mechanism encapsulates correlated pages into a cluster beforehand. All pages belonging to a cluster are scheduled to the same channels to exploit spatial locality, while different clusters are scheduled to different channels to exploit the parallelism. As CAWR covers both garbage collection and I/O performance, it outperforms existing schemes significantly. Trace-driven simulation results demonstrate that the CAWR mechanism reduces the average response time by 26% on average and decreases the valid page copies by 10% on average, while achieving a similar hit ratio to that of existing mechanisms.

• 농촌계획
• /
• 제18권4호
• /
• pp.27-34
• /
• 2012

The purpose of this study is to analyze the community center users' the determinants of utilization & satisfaction for the exploit and to draw out the implication as to what are the influencing factors. The ordered logit model approach was used to examine the determinants. For the use of community center, we surveyed by mail subjecting on rural residents for one month, June 2012, analyzed 625 valid questionnaires. The findings are as follows. First, 'Facility-Satisfaction', 'Education', 'Exploit-Frequency' and 'Age' are the most important factors which affect users' satisfaction. Second, 'A meeting hall function', 'Cultural & Educational function', 'Social & Organizational function', and 'functional criticality function' influence the attributes of users' utilization. Therefore, it is needed to establish the various functions of community center and to prepare the vitalization plan in futuristic viewpoint reflecting the change of rural area. In addition, since there is no clear entity to supervise community center administratively, policy support system to community center should be equipped. Along with these, it is needed to develop managing and operation model for customized community center.

• 안보군사학연구
• /
• 통권9호
• /
• pp.141-190
• /
• 2011

Defense industry as 'a new dynamics of economic growth' policy implies driving policy of defense products' export. The purpose of this study is to suggest suitable strategies to meet with such policy in terms of region and individual nation. The strategies towards advanced region are joint sale strategy for the third countries, extension strategy of trade-off and development strategy of products to exploit niche markets. The strategies towards non-advanced regions are package strategy including exchange of economic development know-how, strengthening strategy of relationships to leading groups in national decision-making processes, exploit strategy of sales market through transfer discard and surplus equipments to other nations, government to government sale strategy towards countries holding low leveled equipment maintaining and management abilities. Finally, successive strategies require leaders' will, active sales diplomacy and active international cooperations of defense industry.

• 산업공학
• /
• 제14권4호
• /
• pp.356-364
• /
• 2001

Production Improvement Method in TOC consists of five steps, but it is very difficult for most firms to implement it because it lacks the detailed methods at each step. This paper suggests some of detailed methods to implement the TOC. In the first step, computer simulation is used to identify the constraints in production lines. Subsequently, ASP, AUT, and CM calculation are defined for the second step, which are helpful to exploit the company's constraints. We also suggest the OEE method to effectively exploit the constraints of production lines in the factory. Finally the TOC/OEE procedure is suggested to optimize the investment in the fourth step. As an illustrative example, we introduce a case of a wafer manufacturer to adopt the suggested methods. The benefits of implementating the suggested methods are addressed in the framework of the balanced scorecard.

• Journal of Communications and Networks
• /
• 제16권2호
• /
• pp.209-216
• /
• 2014

Cognitive radio (CR) has been proposed to solve the spectrum utilization problem by dynamically exploiting the unused spectrum. In CR networks, a spectrum selection scheme is an important process to efficiently exploit the spectrum holes, and an efficient channel allocation scheme must be designed to minimize interference to the primary network as well as to achieve better spectrum utilization. In this paper, we propose a multichannel selection algorithm that uses spectrum hole prediction to limit the interference to the primary network and to exploit channel characteristics in order to enhance channel utilization. The proposed scheme considers both the interference length and the channel capacity to limit the interference to primary users and to enhance system performance. By using the proposed scheme, channel utilization is improved whereas the system limits the collision rate of the CR packets.