• Journal of Korea Multimedia Society
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• v.12 no.1
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• pp.107-121
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• 2009

First reason for generation of standby power is because starting voltage must pass through from the source of electricity to IC. The second reason is due to current when IC is in operation. Purpose of this abstract is on structures of simple modules that automatically switch on or off through analysis of state on standby power and analysis of cutoff point patterns as well as application of algorithms. To achieve this, this paper is based on analysis of electric signals and modeling. Also, on/off cutoff criteria has been established for reduction of standby power. To find on/off cutoff point, that is executed algorithm of similar group and leading pattern group generation in the standby power state. Therefore, the algorithm was defined as an important parameter of the subtraction value of calculated between $1^{st}$ SCS, $2^{nd}$ SCS, and the median value of sampling coefficient per second from a wall outlet.

• Journal of IKEEE
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• v.23 no.4
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• pp.1280-1287
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• 2019

Grid-connected bidirectional PCS(Power Conditioning System) technology is a technology for implementing distributed renewable energy smart grid. And it is always charged by using power collected from solar modules and commercial grid power among vast smart grid systems, and stored when needed.It is a hybrid energy storage device that allows power to be released into the low voltage system. To this end, a PV input power converter with MPPT function, a bidirectional power converter for battery charging and discharging, and a DC Link input are output to a 3 phase 380V AC system, and if nessary, the bidirectional DC/DC converter We designed and developed a PCS with three power converter structures composed of inverters that perform battery charging. Currently, this system is applied to the site of Jeju, which is vulnerable to power outages and fire accidents.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.6
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• pp.9-19
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• 1998

RAID technology that provides the disk I/O system with high performance and high availability is essential for OLTP server. This paper describes the design and implementation of the HIPSS RAID system that has been developed for the SPAX OLTP server. HIPSS has the following design objectives: high performance, high availability, standardization and modularization of external interface, and ease of maintenance. It guarantees high performance by providing 10 independent I/O channels, large data cache, and parity calculation engine. Hardware modularization of the host interface makes it easy to replace host interface hardware module. By providing dual power supply, dual array controller, and disk hot swapping, it provides the system with high availability Implementation of HIPSS and integration test on SPAX has been completed and performance measurement on HIPSS is now going on. In this paper, we provide the detail description for HIPSS system architecture and the implementation results.

• Journal of Advanced Navigation Technology
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• v.21 no.3
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• pp.220-229
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• 2017

In this paper, To take advantage a variety of DC power as the boost DC-DC converter design specifications through the inductor L and capacitor C through PSPICE to calculate the best estimate of the value. Boost DC-DC converter with a switch device using IRF840 and reverse recovery time Schottky diodes with excellent with constant current controller using D10SC6M and resistance can be configured to considering the Power LED Module was driven by the production. Converter's switching frequency is 50 kHz, the first Duty Rate was made to increase gradually depending on the value of the detection were, 10 % in the output voltage. As a result, the simulated Boost Power LED driver characteristics is in comparison with the design specifications, 5% or less as the error was approximated. Finally, when input 15 V were offered, a stable output 24 V were obtained. and Dimming Control through the adjustment of brightness and current consumption were possible.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.468-468
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• 2014

우리나라는 미국, EU, 러시아, 중국, 인도 등 다국간 협력 사업인 국제핵융합실험로(ITER) 사업에 참여하고 있으며, 블랑켓 일차벽 및 시험용 블랑켓 모듈(Test Blanket Module, TBM) 제작기술 개발에 필요한 고열부하 검증시험을 국내에서 자체적으로 실시하기 위한 고열부하시험 시설을 구축하였다. 한국원자력연구원에 설치된 고열부하시험 시설의 주요 사양은 다음과 같다. 열원으로는 전자빔을 사용하며, 빔출력은 최대 300 kW이고, 최대 출력밀도는 $10GW/m^2$이다. 전자빔의 최대 가속전압은 60 kV이고, 최대 조사 면적은 설계상 $70cm{\times}50cm$이다. 고열부하 장비는 핵융합환경과 유사한 고열부하를 시험대상물에 인가하여 접합 및 냉각 성능을 평가하는 장비이며, ITER 블랑켓 및 TBM 일차벽의 경우 약 $0.5MW/m^2$, 가속실험 혹은 사고 시 순간 시나리오 해석을 위해서 $5MW/m^2$까지 고려되기도 한다. ITER 블랑켓 일차벽 제작기술 개발 및 검증(2004~2011)에서는 외국장비(러시아 TSEFEY, 일본 JEBIS, 독일 JUDITH)를 활용하였으나, 고비용 문제와 장비 이용 시간의 제한에 따라 사용이 어려워, 국내에서는 KoHLT-1, 2 장비를 자체 구축하여 활용하여 왔다. 현재는 높은 열부하 인가조건, 약 $5MW/m^2$을 달성하기 위해서 전자빔을 이용한 고열부하시험 장치를 마련하였으며, ITER 블랑켓 일차벽 Semi-Prototype 검증시험, TBM, KSTAR 디버터 실험 등 핵융합로 일차벽 개발에 활용하고 있다. 전자빔, 전원 및 진공 chamber 등 전체 고열부하 시험장치를 구축하여 ITER 장치를 포함해서 토카막 디버터 등 핵융합 플라즈마 대면부품 (Plasma Facing Components, PFC) 재료 개발과 국방, 항공우주 분야의 열유속 게이지 측정법 향상 연구, 로켓 추진 엔진 연소실의 열유속 모니터링 연구, 항공기 프로펠러 연구 등에 활용할 수 있을 것으로 기대된다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8A
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• pp.661-668
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• 2012

In this paper, we introduce the low power wireless communication method and propose new protocol and algorithm for wireless communication which can be applied Active RFID system. Transceiver module is composed of MCU, RF transceiver and chip antenna. and it used the lithium coin battery for power supply. The experimental result is confirmed minimum power consumption which show average $10{\mu}A$(packet transmit) and $30{\mu}A$(packet receive) per second. It can be used ultra low power wireless communication. this result is possible for using the algorithm which predict the arrival time of packet. and it indicates that are possible to prevent malfunction and enhance responsiveness.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.4C
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• pp.437-445
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• 2009

Node of USN(Ubiquitous Sensor Network) environments uses radio based communication mechanism for a delivering message. Thus the multiple hop flooding is necessary for considering limited power and communicating unknown node long-range. However if there are many unknown nodes located in users' vision, the flooding of the radio base is insufficient alternative. Thus as a flash may be used to find a key in a darkness, a more direct and short range communication system is required. This study shall resolve such question through 2 different steps. First a Two kind of code method that convert Text message to color code shall be suggested. Second a hardware module, which may deliver various LED(light-emitting diode) color signal, shall be developed. The experiment may take place by fixing the entry angle of light and distance by setting a specific element as a standard mean.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.12
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• pp.52-57
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• 2011

This paper presents a 4-channel optical transmitter circuit realized in a $0.18{\mu}m$ CMOS technology for high-speed digital interface. Particularly, the VCSEL driver exploits the feed-forward technique, and the pre-amplifier employs the pulse-width control. Thus, the optical transmitter operates at the bias current up to 4mA and the modulation current from $2{\sim}8mA_{pp}$. with the pulse-width distortion compensated effectively. The 4-channel optical transmitter array chip occupies the area of $1.0{\times}1.7mm^2$ and dissipates 35mW per channel at maximum current operations from a single 1.8V supply.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.2C
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• pp.208-218
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• 2008

We are sure that RFID system should be a widely used automatic identification system because of its various advantages and applications. However, many people know that invasions of privacy in RFID system is still critical problem that makes it difficult to be used. Many works for solving this problem have focused on light-weight cryptographic functioning in the RFID tag. An agent scheme is another approach that an agent device controls communications between the tag and the reader for protecting privacy. Generally an agent device has strong security modules and enough capability to process high-level cryptographic protocols and can guarantees consumer privacy. In this paper, we present an enhanced mobile agent for RFID privacy protection. In enhanced MARP, we modified some phases of the original MARP to reduce the probability of successful eavesdropping and to reduce the number of tag's protocol participation. And back-end server can authenticate mobile agents more easily using public key cryptography in this scheme. It guarantees not only privacy protection but also preventing forgery.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.2
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• pp.322-329
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• 2007

A single pixel photon counting type image sensor which is applicable for medical diagnosis with digitally obtained image and industrial purpose has been designed with $0.18{\mu}m$ triple-well CMOS process. The designed single pixel for readout chip is able to be operated by single supply voltage to simplify digital X-ray image sensor module and a preamplifier which is consist of folded cascode CMOS operational amplifier has been designed to enlarge signal voltage(${\Delta}Vs$), the output voltage of preamplifier. And an externally tunable threshold voltage generator circuit which generates threshold voltage in the readout chip has been newly proposed against the conventional external threshold voltage supply. In addition, A dark current compensation circuit for reducing dark current noise from photo diode is proposed and 15bit LFSR(Linear Feedback Shift Resister) Counter which is able to have high counting frequency and small layout area is designed.