• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.12C
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• pp.1238-1244
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• 2002

In this paper, H.235-based security mechanism for H.323 multimedia applications was implemented. H.235 covers authentication using HMAC, Diffie-Hellman key exchange, session key management for voice channel, and encryption functions such as DES, 3DES, RC2. Extra encryption algorithms such as SEED, and AES were also included for possible use in the future. And, we also analyzed the quality of service (QoS), the requirement of implementation, and interoperability to the result in this study. The results could be applied to secure simple IP phone terminals, gateways, or gatekeepers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.6B
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• pp.616-624
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• 2002

In satellite communication, which use the satellite, the protection of TT&C channel which controls the position, performance, and operation is required. In this thesis, we analyzed the weakness of authentication algorithm which is used for protection of TT&C generation and operation. Also, we proposed the authentication algorithm which complements key recovery attack structurely without increasing additional computational amount and verified its performance. The proposed authentication algorithm can satisfy Rivest's recommendation by increasing the computational complexity from $2^{55}$ operations to $2^{111}$ operations. In addition, it can be applied to the existing satellite system because the length of TT&C data and message authentication codes used for the input of authentication algorithm are unchanged.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.6C
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• pp.337-342
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• 2011

In 2009, polar codes, proposed by Arikan, are theoretically proven codes to achieve capacity with acceptable encoding and decoding complexity. Currently, polar codes using channel polarization phenomenon are studied in security and data compression fields etc. In this paper, we consider the practical communication system and propose the construction method of polar codes with finite length and fixed code rate. Also, we show the outstanding performance and corresponding construction method of polar codes found by heuristic simulation.

• Proceedings of the Korean Society of Computer Information Conference
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• 2018.07a
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• pp.466-469
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• 2018

최근 PC를 비롯한 모바일, IOT 기기 등 다양한 환경에서의 사이버 공격이 기승을 부리고 있으며, 그 방법 또한 나날이 발전하고 있다. 이러한 사이버위협으로부터 개인 및 기업의 자산을 지키기 위한 근본적인 대안이 없이는 매번 반복적인 피해를 피하기 어려운 현실이다. 다양한 환경이라고 함은, 다양한 OS(Operation System), 다양한 ISA (Instruction Set Architecture)의 조합으로 이루어지는 사이버환경을 의미한다. 이러한 조합들은 일반 사용자들에게 가장 많이 쓰이는 Windows & Intel 조합의 환경과, Linux & Intel 또는 Linux & ARM 등 기업에서 서비스를 위해 쓰이는 서버 환경 등을 예로 들 수 있다. 그밖에 최근 IOT기기나 모바일 기기와 같은 환경도 있을 수 있다. 바이너리 파일에 대한 보안은 다양한 연구가 진행되고 있지만 그 범위가 방대하고, 깊이가 필요한 영역이라 진입 장벽이 높은 실정이다. 본 논문에서는 이러한 바이너리의 취약점을 분석하기 위한 첫 번째 단계로써 다양한 바이너리 파일을 하나의 정형화된 자료구조로 변환하는 바이너리 포맷 분석기의 한 방법을 제시하고자 한다. 다양한 OS와 다양한 ISA환경에서 사용되는 바이너리들에서 공통적으로 존재하는 정보들 중, 바이너리의 취약점 분석을 위해 필요한 데이터를 보다 효율적으로 수집하고, 관리하는 것이 바이너리를 통한 사이버 위협을 탐지하는 연구에서 기초가 된다고 할 수 있기 때문이다.

• The Transactions of the Korea Information Processing Society
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• v.4 no.5
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• pp.1319-1326
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• 1997

The Internet is a very convenient neteork, but not always a So.many orvanizations often require administrative security policies when they want to connect with ther organizations thtough a pubic network.A firewall is one way of protecting an internal network from the untrusted extemal network with a mechanism for selectively permiting or blocking traffic between the intermal network and the extermal network. The firewall also provides some limited Intemet access such as Ftp.Telet, etc.Usually , through a firewall system, X applications running on the extermal network may not access an X display on the intermal network.Thus, X applications run-ning on the extemal network are not supported through the usual firewall.In this paper, we propose a method of suppoting X application programs effedtively dffectvely through the firewall, overcoming this restriction.

• Journal of Convergence Society for SMB
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• v.5 no.1
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• pp.13-18
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• 2015

The malware, as hackers generic name of executable code that is created for malicious purposes, depending on the presence or absence of a self-replicating ability infected subjects, and are classified as viruses, worms, such as the Trojan horse. Mainly Web page search and P2P use, such as when you use a shareware, has become penetration is more likely to occur in such a situation. If you receive a malware attack, whether the e-mail is sent it is automatically, or will suffer damage such as reduced system performance, personal information leaks. While introducing the current malware, let us examine the measures and describes the contents related to the malicious code.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.7
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• pp.499-506
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• 2003

In this paper, we propose the shift and noise tolerance method using a virtual phase image and a joint transform correlator (JTC) architecture that can alleviate the need for an accurate optical axis alignment. An encrypted image is obtained by the Fourier transform of the product of a phase- encoded virtual image to camouflage the original one and a random phase image. Therefore, even if unauthorized users analyze the encrypted image, we can prevent the possibility of counterfeiting from unauthorized people using virtual image which dose not contain any information from the original image. We demonstrate the robustness to noise, to data loss and to shift of the encrypted image using a JTC in the proposed description technique.

• 전자공학회논문지 IE
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• v.48 no.2
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• pp.12-18
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• 2011

In this paper, did numerical simulation to confirm LED module for lighting and protection against heat special quality of heat sink device. Analysis was gone dividing on case that emitting light side turns normalcy department considering that eat of device according to usage and case that turn down looking being street lamp of 200 W or security appointment lighting device analysis case, and also, volume of thermal element divides on big case and small case and analyzed. Confirmed that can do so that may discharge LED's thermal value to outside enough in analysis wave and current heat sink shape, and investigated that difference of protection against heat performance according to position of device and size of thermal element appears.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2622-2627
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• 2010

The accuracy of face recognition used unmanned security system is very important and necessary. However, face recognition is a lot of restriction due to the change of distortion of face image, illumination, face size, face expression, round image. We propose a hybrid neural network for improve the performance of the face recognition. The proposed method is consisted of SOM and LVQ. In order to verify usefulness of the proposed method, we make a comparison between eigenface method, hidden Markov model method, multi-layer neural network.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.430-432
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• 2015

This paper describes a hardware implementation of ultra-lightweight block cipher algorithm PRESENT-80/128 that supports for two master key lengths of 80-bit and 128-bit. The PRESENT algorithm that is based on SPN (substitution and permutation network) consists of 31 round transformations. A round processing block of 64-bit data-path is used to process 31 rounds iteratively, and circuits for encryption and decryption are designed to share hardware resources. The PRESENT-80/128 crypto-processor designed in Verilog-HDL was verified using Virtex5 XC5VSX-95T FPGA and test system. The estimated throughput is about 550 Mbps with 275 MHz clock frequency.