• Journal of Electrical Engineering and Technology
• /
• v.7 no.2
• /
• pp.141-150
• /
• 2012

The present study examines an efficient congestion management system compatible with the evolving environment. The key is to build an information model shared and exchanged for marketbased solutions to alleviate congestion. Traditional methods for congestion management can be classified into two categories, i.e., the centralized scheme and the decentralized scheme, depending on the extent to which the independent system operator (ISO) is involved in market participants' (MPs) activities. Although the centralized scheme is more appropriate for providing reliable system operation and relieving congestion in near real-time, the decentralized scheme is preferred for supporting efficient market operation. The minimum set of information between the ISO and MPs for decentralized scheme is identified: i) congestion-based zone, ii) Power Transfer Distribution Factors, and iii) transmission congestion cost. The mathematical modeling of the proposed information is expressed, considering its process of making effective use of information. Numerical analysis is conducted to demonstrate both cost minimization from the MP perspective and the reliability enhancement from the ISO perspective based on the proposed information exchange scheme.

• The KIPS Transactions:PartC
• /
• v.11C no.4
• /
• pp.497-508
• /
• 2004

The existing wireless LAN standard IEEE802.11b has many vulnerabilities from security point of view. The authentication mechanisms in IEEE802.11b have many vulnerabilities. As a result to complement the weak of IEEE802.11b authentication, the IEEE802.1x had been developed in the sense of providing strong user authentication with appropriate mechanism. But this mechanism does not perform AP authentication and there are also some weak points. And in confidentiality and message Integrity case, WEP is weak from key stream reuse attack, IV reuse attack and so on. For that reason, in this paper we propose secure wireless LAN system. Our system provides strong user authentication, confidentiality, and message integrity based on existing IEEE802.1x framework and TLS.

• Journal of Multimedia Information System
• /
• v.3 no.4
• /
• pp.141-148
• /
• 2016

This paper proposes a medium access control (MAC) protocol for multiple-input multiple-output (MIMO) ad-hoc networks. Multiple-packet receptions in MIMO systems have attracted as a key technique to achieve a high transmission rate. In the conventional protocols for multiple-packet receptions, timing offsets among multiple-frame transmissions cause frame collisions induced by hidden nodes, which degrades network performance. In the proposed protocol, transmission synchronization among hidden nodes can be achieved by applying pulse/tone exchanges. By applying the pulse/tone exchanges, multiple-packet receptions among hidden nodes can be achieved, which enhances network throughputs compared with the conventional protocol. Simulation results show effectiveness of the proposed protocol.

• Proceedings of the IEEK Conference
• /
• 2002.06c
• /
• pp.51-54
• /
• 2002

P2P implies direct exchange between peers. If you have something I want, 1 go directly to you and obtain il. There is one of the most advantages of formation of community in P2P. For a specified purpose through P2P, the Peers who make temporary a group delivery a request efficient and safe. And the resources can be jointed common, cooperation and communication. When P2P is developed more, we can expect more formation of online community and development. But to be a safe of personal ID and password in internet, it should be possible to make a key-exchange. In the paper, it suggest P2P security system suitable to personal security that Kerberos be transformed. The user who make community in P2P, have Kerberos Server, and using Physical Address of Ethernet card in personal computer, authenticate users.

• Nuclear Engineering and Technology
• /
• v.53 no.3
• /
• pp.763-775
• /
• 2021

The thermal hydraulic performances of Steam Generator (SG) under both steady and transient operation conditions are of great importance for the safety and economy in nuclear power plants. In this paper, based on our self-developed SG thermal hydraulic analysis code STAF (Steam-generator Thermalhydraulic Analysis code based on Fluent), an improved new version STAF-CT (fully Coupling and Transient) is developed and introduced. Compared with original STAF, the new version code STAF-CT has two main functional improvements including "Transient" and "Fully Three Dimensional Coupling" features. In STAF-CT, a three dimensional energy transferring module is established which can achieve energy exchange computing function at the corresponding position between two sides of SG. The STAF-CT is validated against the international benchmark experiment data and the results show great agreement. Then the U-shaped SG in AP1000 nuclear power plant is modeled and simulated using STAF-CT. The results show that three dimensional flow fields in the primary side make significant effect on the energy source distribution between two sides. The development of code STAF-CT in this paper can provide an effective method for further SG high fidelity research in the nuclear reactor system.

• Journal of Digital Convergence
• /
• v.10 no.3
• /
• pp.105-111
• /
• 2012

Internet Protocol Television (IPTV) through broadband cable network is a subscriber-based system which consists of software and set-top box. However, a weakness for the current IPTV system is the lack of security between users and CAS. This paper proposes a user authentication protocol at STB, which limits the service by the user-valued attribute to prevent illegal IPTV users. User attribute values change the order with bit form according to the certain rule, and apply to one-way hash function and Diffie-Hellman's elliptic curve key-exchange algorithm. The proposed protocol is able to improve on user authentication and computation. Also, each user generates an authentication message by smart card and receives various services based on the user-valued attribute.

• Annual Conference of KIPS
• /
• 2005.05a
• /
• pp.1071-1074
• /
• 2005

The ECC(Elliptic Curve Cryptogrphics), one of the representative Public Key encryption algorithms, is used in Digital Signature, Encryption, Decryption and Key exchange etc. The key operation of an Elliptic curve cryptosystem is a scalar multiplication, hence the design of a scalar multiplier is the core of this paper. Although an Integer operation is computed in infinite field, the scalar multiplication is computed in finite field through adding points on Elliptic curve. In this paper, we implemented scalar multiplier in Elliptic curve based on the finite field $GF(2^{163})$. And we verified it on the Embedded digital system using Xilinx FPGA connected to an EISC MCU(Agent 2000). If my design is made as a chip, the performance of scalar multiplier applied to Samsung $0.35\;{\mu}m$ Phantom Cell Library is expected to process at the rate of 8kbps and satisfy to make up an encryption processor for the Embedded digital information home system.

• Proceedings of the Korean Information Science Society Conference
• /
• 2002.10e
• /
• pp.139-141
• /
• 2002

최근 보안에 관한 관심이 높아지면서 IPSec을 이용한 VPN system이 널리 이용되고 있다. IPSec에서 암호화에 사용되는 키를 생성하는 IKE는 IPSec의 핵심 프로토콜이지만다소 복잡하고 메시지 교환도 많아 패킷의 손실이 큰 무선망에는 적합하지 않다. 무선망에서 좀 더 효율적으로 동작하기 위한 인터넷 키 교환 방법 및 공개키 기반구조를 제시하였다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2002.10e
• /
• pp.415-417
• /
• 2002

운영체제가 지원되지 않는 소규모 기기에서 IPv6의 보안기능을 고성능으로 제공하기 위해본 연구실에서는 IPv6용 IPsec 프로토콜과 암호화 알고리즘을 하드웨어로 구현하였다. 이러한 IPv6용 하드웨어 IPsec을 기반으로 한 보안 서비스를 제공하기 위해서는 안전한 키의 교환과 인증이 중요하다. 이를 위하여 본 논문에서는 IPv6용 하드웨어 IPsec을 위한 키 교환시스템으로서 IKE Module을 설계하여 드라이버 프로그램으로 구현하였다. 그리고 구현된 IKE Module을 IPv6용 하드웨어 IPsec의 드라이버로 탑재하여 기존의 소프트웨어 IKE Module과의 테스트를 통하여 기능을 검증하였다.

• Convergence Security Journal
• /
• v.2 no.1
• /
• pp.59-68
• /
• 2002

The smart card including memory and processor is able to simple process such as privilege unauthorized access and used to Authentication System for security. In this paper, we propose using the smart card in the key exchange phase when secure Internet phones conversation, so certainly guarantee to mutual authentication and secret communication.