• Journal of Power Electronics
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• v.12 no.6
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• pp.869-877
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• 2012

This paper presents a current-balancing circuit for security lights that uses parallel-connected LEDs. The parallel connection of LEDs causes current differences between the LED strings because of characteristic deviations. These differences can reduce the lifespan of a particular point of LEDs by thermal spotting. They can also cause non-uniform luminance of the lighting device. Among the different methods for solving these problems, the method using current-balancing transformers makes it easy to compensate for current differences and it has a simple circuitry. However, while the balancing transformer has been applied to AC light sources, LEDs operate on a DC source, so the driving circuitry and the design method have to be changed and their performances must be verified. Thus in this paper, a design method of the balancing transformer network and the driving circuitry for LEDs is proposed. The proposed design method could have a smaller size than the conventional design method. The proposed circuitry is applied to three types of 100-watt LED security lights, which use different LEDs. Experimental results are presented to verify the performance of the designed driving circuits.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1480-1484
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• 2003

This paper presents the design and development of network for housing estate security system. The system can cover up to 961 houses which can be up to 1,200 meters long transfer rate of 9,600 bps. This system uses checking and warning the abnormal situation. More over this system has ability to control switch on/off the electrical equipment in the house via AC line control system. The system consists of 4 parts. The first part is a security system of each house using MCS-51 microcontroller as a central processing unit scan 32 sensors and control 8 appliances and send alarm. The MCS-51 microcontroller received control signal via telephone used DTMF circuit. The second part is distributed two levels master/slave network implementing after RS-485 serial communication standard. The protocol its base on the OSI (Open Systems Interconnection) 7 layers protocol model design focus on speed, reliability and security of data that is transferred. The network security using encrypt by DES algorithm, message sequence, time stamp checking and authentication system when user to access and when connect new device to this system. Flow control in system is Poll/Select and Stop-and-Wait method. The third part is central server that using microcomputer which its main function are storing event data into database and can check history event. The final part is internet system which users can access their own homes via the Internet. This web service is based on a combination of SOAP, HTTP and TCP/IP protocols. Messages are exchanged using XML format [6]. In order to save the number of IP address, the system uses 1 IP address for the whole village in which all homes and appliance in this village are addressed using internal identification numbers. This proposed system gives the data transfer accuracy over 99.8% and maximum polling time is 1,120 ms.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.11
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• pp.2497-2506
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• 2010

Smart power grid is targeting to improve grid operation by integrating existing power IT technologies in the jeju smart grid field test. Real-time two-way communication and interoperability in power grid are essential to smart power grid. Adopting smart grid will increase security vulnerabilities in power grid by increasing the number of wireless sensors and the chances of the external exposure of communication networks. In addition, hackers can cause chaos in the power grid system with eavesdropping and forgery attacks in communication networks. Smart power grid is one of the most important systems in deploying smart grid, and it is important to design security system systematically since smart grid can be seriously damaged when problem occurs. In this paper, local and global smart grid security standard and security vulnerabilities in power grid are reviewed, and 2 level smart grid service model is proposed.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.10
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• pp.1485-1490
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• 2013

The demonstration project of the electrical grid for Smart grid is progressed, the smart digital appliances AV technology, Smart home energy management technology charging the management function of complex energy for the automation management of air conditioning and heating, humidity and air, the health care technology charging the design of housing for the elderly and disabled and the measurement of individual bio information, and the Smart home security technology dealing with the biometric security and motion sensors, etc. have been studied. The power monitoring terminal which uses a variety of wired and wireless networks and protocol is the target additionally to be considered in addition to the security vulnerabilities that was occurred in the existing terminal. In this research paper, the author analyzes the cryptographic techniques corresponding to the smart meter occurred by the problems that are exposed on the outside which are vulnerable to physical attacks, and intends to propose the design of the security systems for the Smart meter terminal being able to maximize the efficiency of the terminal.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3327-3334
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• 2021

Present electric grids are advanced to integrate smart grids, distributed resources, high-speed sensing and control, and other advanced metering technologies. Cybersecurity is one of the challenges of the smart grid and nuclear plant digital system. It affects the advanced metering infrastructure (AMI), for grid data communication and controls the information in real-time. The research article is emphasized solving the nuclear and smart grid hardware security issues with the integration of field programmable gate array (FPGA), and implementing the latest Time Authenticated Cryptographic Identity Transmission (TACIT) cryptographic algorithm in the chip. The cryptographic-based encryption and decryption approach can be used for a smart grid distribution system embedding with FPGA hardware. The chip design is carried in Xilinx ISE 14.7 and synthesized on Virtex-5 FPGA hardware. The state of the art of work is that the algorithm is implemented on FPGA hardware that provides the scalable design with different key sizes, and its integration enhances the grid hardware security and switching. It has been reported by similar state-of-the-art approaches, that the algorithm was limited in software, not implemented in a hardware chip. The main finding of the research work is that the design predicts the utilization of hardware parameters such as slices, LUTs, flip-flops, memory, input/output blocks, and timing information for Virtex-5 FPGA synthesis before the chip fabrication. The information is extracted for 8-bit to 128-bit key and grid data with initial parameters. TACIT security chip supports 400 MHz frequency for 128-bit key. The research work is an effort to provide the solution for the industries working towards embedded hardware security for the smart grid, power plants, and nuclear applications.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.126-128
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• 2004

This paper proposes design and implementation for IKE system that is available to IP security communication on IPv6 network. IPsec is a standard for security on network or processing layer of network communication. IPsec consists of step to negotiate security policy and step to negotiate and provide security key material for peer-to-peer security. We use the ISAKMP for negotiating security policy. And we use the IKE for negotiating and providing the key material. The system is based on VxWorks and is tested with Racoon that is a IKE daemon on FreeBSD. In this paper, we propose an implementation method for mobile host providing network communication with IP security.

• Convergence Security Journal
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• v.6 no.1
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• pp.83-90
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• 2006

Recently, the security for RFID/USN environment is divided into network security and RFID security. The authentication protocol design for RFID security is studied to protect user privacy in RFID system. However, the study of efficient authentication protocol for RFID system is not satisfy a security for low-cost RFID tag and user privacy. Therefore, this paper proposes a secure matrix-based RFID authentication protocol that decrease communication overhead and computation. In result, the Matrix-based RFID authentication protocol is an effective authentication protocol compare with HB and $HB^+$ in traffic analysis attack and trace location attack.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2006.06a
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• pp.515-518
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• 2006

RFID(Radio Frequency Identification) 시스템이란 무선 라디오 주파수를 이용하여 사물을 식별 및 추적할 수 있는 기술로서 산업 전반에 걸쳐 그 적용성이 확대되고 있으나 불안전한통신상에서 데이터 송 수신 및 태그의 제한적인 계산능력과 한정된 저장 공간의 자원으로 인한 위치 추적, 스푸핑 공격, 재전송공격, 사용자 프라이버시 침해 등의 취약점이 존재한다. 본 논문에서는 기존의 RFID 시스템에 대한 인증 프로토콜들을 분석하고, Challenge Response(C-R) 인증 프로토콜에서 연산량을 줄임으로서 위치 추적과 스푸핑 공격, 재전송 공격에 효율적으로 개선된 C-R 인증 프로토콜을 제안한다.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2006.06a
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• pp.731-734
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• 2006

RFID(Radio Frequency Identification)는 무선 주파수를 이용하여 물리적인 접촉 없이 개체에 대한 정보를 읽거나 기록하는 자동인식 기술이다. 그러나 RFID의 특성으로 인하여 사용자의 프라이버시 침해가 발생하면서 이를 해결하기 위한 많은 프로토콜들이 제안되었으나 공격자의 여러 공격 형태로 인하여 많은 취약점이 발생하였다. 최근 저가형 RFID를 위한 효율적인 인증프로토콜이 제안되었으나 공격자의 불법적인 태그에 대해 인증이 가능한 문제점을 해결하는 연구가 요구된다. 본 논문에서 제안된 프로토콜은 기존의 인증 프로토콜에서 리더에게 역할을 부여함으로써 처음 생산된 태그에 대해서도 위조된 태그의 인증이 불가능하다. 또한 연산량이 적은 장점과 더욱 강화된 보안성으로 인하여 안전하고 효율적인 저가의 RFID 태그에 적용이 가능할 것이다.

• The Journal of Information Systems
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• v.24 no.3
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• pp.1-19
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• 2015

Purpose This study discusses the contradictory behavior of smart-phone users who consider security is important, but they do not follow the security recommendations. We found through literature research that this contradictory behavior is resulted from a low level of efficacy. Design/methodology/approach Research hypotheses were set based on Extended Parallel Process Model, Control Theory, and Self Efficacy Mechanism. The data were collected from undergraduate students. Total of 178 data were used for the analysis. Findings Results of the analysis, first, showed that the relationship between threat and security attitude varies with the level of coping efficacy. Second, showed that the relationship between threat and fear does not vary with the level of coping efficacy. Both the groups with high coping efficacy and low coping efficacy had a statistically significant effect on the relationship between threat and fear.