• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.63-67
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• 2014

A distributed zero-beamforming based cooperative jamming technique is useless when an eavesdropper detects the sharing seed. In addition, the currently alternatives are very limited when the eavesdropper is located nearby a source for wiretapping. This letter presents a solution to this extreme case. Relay randomly generates and transmits a binary jamming message to both source and destination in the first phase. When these two receivers securely and correctly decode the message, the source creates and transmits another message based on the use of exclusive-or for its information message and the decoded message. Consequently, the next transmission can avoid the eavesdropping.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.266-267
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• 2017

A numerical investigation of the stage separation behavior of two-body vehicle focusing on its flow characteristics were carried out. For this simulation, separation of a booster from vehicle was modeled by a chimera grid system and calculated by using commercial code, CFD-FASTRAN$^{TM}$. Consideration of a spring force, gravity and relative acceleration of a booster was the essential factor that simulates the realistic situation. In this study, It was validated that the booster separation time decreases with increase in flight mach number and angle of attack. In view of the results so far achieved, it was expected that the dynamics modeling and boundary condition set up applied in this study will be helpful in a estimation of a safe stage separation and event sequence of flight test.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.397-400
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• 2011

MDO Optimization for a low pressure axial compressor rotor has been carried out to improve aerodynamic performance and structural stability. Global optimized solution was obtained from an artificial neural network model with genetic algorithm. Optimized rotor model has a high blade loading near hub and near zero incidence flow angle near tip region to reduce the incidence loss and flow separation at trailing edge region. Also the rotor shape is converged to a trapezoid shape to reduce the maximum stress occurred at the root of the blade. Numerical simulation results show that rotor has 87.6% rotor efficiency and safety factor over than 3.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.4 s.310
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• pp.66-73
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• 2006

Safety is the most important for all traffic management and control technology. This paper focuses on developing a flexible, reliable and real-time processing algorithm which is able to generate signal for the entering vehicle at the joining road through a camera and image processing technique. The images obtained from the camera located beside and upon the road can be used for traffic surveillance, the vehicle's travel speed measurement, predicted arriving time in joining area between main road and joining road. And the proposed algorithm displays the confluence safety signal with red, blue and yellow color sign. The three methods are used to detect the vehicle which is driving in setted detecting area. The first method is the gray scale normalized correlation algorithm, and the second is the edge magnitude ratio changing algorithm, and the third is the average intensity changing algorithm The real-time prototype confluence safety signal generation algorithm is implemented on stored digital image sequences of real traffic state and a program with good experimental results.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.2
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• pp.211-222
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• 2023

Multivariate quadratic equations (MQ)-based public-key cryptographic algorithms are one of promising post-quantumreplacements for currently used public-key cryptography. After selecting to NIST Post-Quantum Cryptography StandardizationRound 3 as one of digital signature finalists, Rainbow was cryptanalyzed by advanced algebraic attacks due to its multiple layered structure. The researches on MQ-based schemes are focusing on UOV with a single layer. In this paper, we propose a new MQ-signature scheme based on UOV using the combinations of the special structure of linear equations, spare polynomials and random polynomials to reduce the secret key size. Our scheme uses the block inversion method using half-sized blockmatrices to improve signing performance. We then provide security analysis, suggest secure parameters at three security levels and investigate their key sizes and signature sizes. Our scheme has the shortest signature length among post-quantumsignature schemes based on other hard problems and its secret key size is reduced by up to 97% compared to UOV.

• Food Science and Preservation
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• v.30 no.3
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• pp.538-545
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• 2023

This study aimed to assess the in vitro safety of a probiotics mixture (Lactobacillus acidophilus PBS066, Lactiplantibacillus plantarum PBS067, and Limosilactobacillus reuteri PBS072), along with its inhibitory effect on carbohydrate digestion. All three strains met the antibiotic resistance profile of the European Food Safety Authority (EFSA) guidelines. None of the strains exhibited hemolytic activity or cytotoxicity against Caco-2 cells. Strains PBS067 and PBS072 inhibited α-amylase activity, whereas all three strains suppressed α-glucosidase activity, indicating that the mixture might limit carbohydrate digestion in the gastrointestinal tract. These findings support the safety of this probiotics mixture and its potential to modulate carbohydrate metabolism in the gut.

• Aerospace Engineering and Technology
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• v.9 no.2
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• pp.198-203
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• 2010

KSLV-I, a.k.a. Naro is the 1st Korean satellite launch vehicle, which was launched at Naro space center by Korea Aerospace Research Institute (KARI) in AUG. 2009, and JUN. 2010. Although the missions of 1st and 2nd launch of KSLV-I - inject the space craft into the designated orbit - were not successful, safety of launch vehicle was accomplished through the cooperation with the Russian partner Khrunichev Space Research and Production Center (KhSC). Both parties co-developed the safety management program to ensure launch safety. In this paper, the analysis and contents of safety program are illustrated.

• 프린팅코리아
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• v.14 no.10
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• pp.82-83
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• 2015

최근의 인쇄업계는 단납기, 치열한 경쟁에 의한 납품가격 하락 등의 어려움을 겪고 있다. 게 다가 전반적인 인쇄업계의 불황으로 인해 잉크와 관련한 새로운 요구에 직면하고 있다. 잉크 비용의 절감이나 품질의 향상 및 사용자에 대한 안전성 확보에 대한 고객의 요구는 물론이고, 환경 이슈에 대한 대응이 라는 새로운 과제가 부각되고 있다.

• Electric Engineers Magazine
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• s.355
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• pp.46-47
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• 2012

2012. 1. 17(화) 11:40분경, 강원도 동해시 소재 ${\bigcirc}{\bigcirc}$공장내 변압기실에서 단로기를 개방하지 않은 상태에서 GPT(접지용 변압기)의 접지단자를 접속하는 작업 중에 GPT 상부의 인출된 부상애자의 충전부에 접촉하여 감전 추락 사망한 사고임.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.8
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• pp.78-84
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• 2002

그리드 환경에서 사용자는 각 시스템을 사용하는데 있어서 하나의 사이트에 한번 로그인을 한 후에 다른 그리드 상의 지원에 접근할 때 추가적인 인증 과정을 거치지 않는다는 단일 인증(Single Sign on)과 같은 인증서비스, 실제로 그 사용자가 해당 시스템을 사용할 수 있는지에 대한 권한에 관련된 접근제어(Access Control) 서비스 등과 같은 보안문제에 대한 기반이 뒷받침되어야 효과적이고 안전하게 수행될 수 있을 것이다.