• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.323-323
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• 2005

• Journal of the Korean Chemical Society
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• v.63 no.5
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• pp.323-326
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• 2019

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.323-326
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• 2005

Several video coding standards, such as MPEG-4 and H.263, have been investigated to reduce the resulting number of bits while pursuing the maximum video quality. The recent video coding standard, H.264, provides higher coding efficiency than previous coding standards by using the mode decision scheme. For mode decision, H.264 chooses the best macroblock mode among the several candidates using Lagrangian cost function which reflects both the rate and the distortion. H.264 employs only one rate-distortion optimization (RDO) model for all macroblocks. Since the characteristics of each macroblock is different, each macroblock should have its own RDO model. In this paper, we propose an adaptive rate-distortion optimization algorithm for H.264. We regulate the Lagrangian multiplier considering the picture type and characteristics of each macroblock.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.313-323
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• 2014

Sensor fault detection and isolation problems subject to H_/$H_{\infty}$, performance are concerned for linear time-invariant systems with time delay in a state and parametric uncertainties. To that end, a model-based observer bank approach is pursued. The design conditions for both continuous- and discrete-time cases are formulated in terms of matrix inequalities, which are then converted to the problems solvable via an algorithm involving convex optimization.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.323-328
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• 2009

Cryotin F could be used for hydrolyzing shrimp byproducts into bioactive ingredients, which could be used as value-added products. The objective of this study was to investigate the optimum condition for antioxidative activities of the enzymatic hydrolysate produced with Cryotin F using response surface methodology with central composite rotatable design. Shrimp byproducts (shells and heads) were hydrolyzed with Cryotin F. The experimental ranges of the independent variables for 20 experimental runs were 28.2-61.8${^{\circ}C}$ reaction temperature, pH 6-10 and 0.5-5.5% enzyme concentration. The degree of hydrolysis for the reaction products was measured. Their antioxidative activities were measured using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity and Fe-chelating activity. The experimental method with central composite rotatable design was well designed to investigate the optimum condition for biofunctional ingredients with antioxidative activities using Cryotin F because of their high R2 values of 0.97 and 0.95 for DPPH-scavenging activity and Fe-chelating activity, respectively. Change in enzyme concentration did not significantly affect their antioxidative activities (p<0.05). Both DPPH scavenging activity and chelating activity against Fe for the enzyme hydrolysates were more affected by the pH of enzyme hydrolysis than by their action temperature. DPPH-scavenging activity was higher at acidic pH than alkali pH, while chelating activity against Few was inversely affected. Hydrolysate of shrimp byproducts showed high antioxidative activities depending on the treatment condition, so the optimum treatment of enzymatic hydrolysate with Cryotin F and other proteases can be applied to shrimp byproducts (shells) and other protein sources for biofunctional ingredients.

• Journal of Advanced Navigation Technology
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• v.17 no.4
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• pp.421-428
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• 2013

Voice over IP refers to technology that enables routing of voice conversations over the Internet or a TCP/IP network. VoIP communication costs cheaper than traditional analog phone. Phone calls can be made to anywhere / anyone: Both to VoIP numbers as well as people with normal phone numbers. VoIP protocol equipment available today follows the SIP standard. Older VoIP equipment though would follow H 323, MGCP, Megaco/H.248. A SIP server is the main component of an IP PBX, dealing with the setup of all SIP calls in the TCP/IP network. A SIP server is also referred to a Asterisk IP-PBX. A VoIP telephone, also known as a SIP phone or a softphone, allows the user to make phone calls to any softphone, mobile or PC by using App store. A VoIP telephone can be a simple software-based softphone. However, the SIP Server and the program is vulnerable to VoIP attacks. In this paper, eavesdropping attacks tested by using the Asterisk SIP server. Eavesdropping attacks and TLS security methods apply to VoIP system. TLS can be applied to determine whether the eavesdropping available for VoIP Environments.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.323-325
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• 1993

In this paper, the decentralized suboptimal $H_2$ filtering problem is considered. An additional term is added to the centralized optimal $H_2$ filter so that the whole filter is decentralized. We derive a sufficient condition for existence of such decentralized filters. By employing the solution procedure for the exact model matching problem, we obtain a set of decentralized $H_2$ filters, and choose a suboptimal filter from this set of decentralized $H_2$ filters. Naturally the resulting filter is guaranteed to be stable.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.323-325
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• 1990

In this paper, a new method to track the maximum power point is presented. The proposed scheme achieves the maximum power the step-up chopper, which tracks the maximum power point by sensing only the actual current from the photovoltaic array. Also it adopts the protect ion circuit to protect the battery system against the overvoltage and overvoltage by utilizing hysterisis characteristic.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2001.11a
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• pp.241-245
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• 2001

인터넷 서비스와 함께 발달한 멀티미디어 서비스 중 각광받고 있는 VoIP 서비스는 유선 전화보다 저렴한 가격을 바탕으로 하여 호황을 누리고 있다. 그러나 인터넷을 전송망으로 이용하는 VoIP는 개인의 암호화되지 않은 음성데이터의 도청이 쉽게 이루어질 수 있을 뿐만 아니라 사용자 및 서비스 업자에 대한 인증 방법 부재로 인한 불법 이용이 예상되는 등 보안적 문제점을 가지고 있다. 그에 따른 VoIP 서비스의 보안 요구사항은 계속 증가하고 있으며 이에 대한 연구 노력이 시급하다. 본 논문에서는 ITU에서 제안한 H.323 VoIP의 보안 프로토콜인 H.235에 대하여 연구하고 이를 구현한 VoIP 보안 시스템을 구축하여 VoIP 보안 프로토콜의 요구 사항 및 방향을 제시하였다.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.323-328
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• 2005

이 논문에서는 Linux 기반의 서버/클라이언트 구조에서 H.264 Content에 대한 IPMP 시스템을 구현하고자 한다. DRM(Digital RIghts Management)솔루션을 제공해주는 IPMP(Intellecutual Property Management and Protection)를 관련 참조 소프트웨어들의 변경 통합과정을 거쳐 H.264에 대한 IPMP 시스템을 구현했다.