• ETRI Journal
• /
• v.33 no.5
• /
• pp.818-821
• /
• 2011

A D-band subharmonically-pumped resistive mixer has been designed, processed, and experimentally tested. The circuit is based on a $180^{\circ}$ power divider structure consisting of a Lange coupler followed by a ${\lambda}$/4 transmission line (at local oscillator (LO) frequency). This monolithic microwave integrated circuit (MMIC) has been realized in coplanar waveguide technology by using an InAlAs/InGaAs-based metamorphic high electron mobility transistor process with 100-nm gate length. The MMIC achieves a measured conversion loss between 12.5 dB and 16 dB in the radio frequency bandwidth from 120 GHz to 150 GHz with 4-dBm LO drive and an intermediate frequency of 100 MHz. The input 1-dB compression point and IIP3 were simulated to be 2 dBm and 13 dBm, respectively.

• Journal of Korea Society of Industrial Information Systems
• /
• v.18 no.1
• /
• pp.19-24
• /
• 2013

As CMOS technology is scaled down more aggressively, the reliability mechanism (or aging effect) caused by the diffusion of metal atoms along the conductor in the direction of the electron flow, also called electromigration (EM), has become a major reliability concern. With the present of EM, it is difficult to control the current flows of the MOSFET device and interconnect. In addition, nanoscale CMOS circuits suffer from increased gate leakage current and power consumption. In this paper, the EM effects on current of the nanoscale CMOS circuits are analyzed. Finally, this paper introduces an on-chip current measurement method providing lifetime electromigration management which are designed using 45-nm CMOS predictive technology model.

• Journal of Power Electronics
• /
• v.11 no.5
• /
• pp.751-758
• /
• 2011

This paper presents an effective robust predictive control scheme for the active power filter (APF) using a smith-predictor based current regulator, which show superior features when compared to proportional-integral (PI) controllers in terms of an enhanced closed-loop bandwidth and an improved current tracking accuracy. A moving average filter (MAF) is implemented using a field programmable gate array (FPGA) for signal pre-processing to eliminate the switching ripple contamination. An adaptive linear neural network (ADALINE) is used for individual harmonic estimation to achieve selective compensation purpose. The effectiveness and validity of the devised control algorithm are confirmed by extensive simulation and experimental results.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.64 no.5
• /
• pp.689-693
• /
• 2015

Recently, many advanced countries are devoted to the development of eco-friendly new-renewable energy to prepare for the depletion of resources. Korea belongs to the absolute lack of energy to import from abroad 97% of energy use. So, development and supply of eco-friendly energy such as small hydro power has been required even more. Our country has a large number of small-sized reservoirs and dams. So, hydro generator has been installed at the small reservoirs and dams with the economy. Since the discharge flow of agricultural reservoir is not constant, the guide vane of wicket gate is used for adjusting the output of the generator.

• 한국정보통신설비학회:학술대회논문집
• /
• 2008.08a
• /
• pp.277-280
• /
• 2008

Starting from 2005, as the new city paradigm, the term 'u-City' was created in Korea. U-City service, as defined in "u-City law", is a service that connects and intermediates among government, traffic, welfare, environment, disaster mitigation, etc., and their data based on ubiquitous city technology and infrastructure. According to the survey executed by local governments, the improvements in the standard of living of citizens have in turn increased the needs for anti-mitigation services. Such trend is bolstered with the recent disasters such as the conflagration of Korean Soong-rae Gate and the devastating earthquake of Sichuan province. This article describes a concept of the u-City disaster prevention service and looks into the activities and planning of u-City disaster prevention service of local governments. This paper also briefly looks into the law and policies to derive the needs of u-City disaster prevention service as well as the current technologies and u-City disaster prevention services of local governments. Ultimately, this paper offers the strategic direction of developing u-Disaster Prevention City.

• Journal of information and communication convergence engineering
• /
• v.2 no.2
• /
• pp.76-79
• /
• 2004

The DS-SS (Direct Sequence Spread Spec1nun) transmitter is part of a low data rate (∼150 kbps - burst rate and 64 bps - average data rate) wireless communication system. It is traditionally implemented using Digital Signal processing chip (DSP). However, with rapid increase in variety of services through cell phones, such as, web access, video transfer, online games etc. demand for higher rate is increasing steadily. Since the chip rate and thereby the sampling rate requirements of the system are fairly high, the transmitter should implemented using Field programmable Gate Arrays FPGAs instead of a DSP. This paper shows the steps taken to get a working prototype of the transmitter unit on a FPGA based platform.

• Transactions on Electrical and Electronic Materials
• /
• v.18 no.4
• /
• pp.195-198
• /
• 2017

This research analyzed the electrical characteristics of an 80 V optimal trench power MOSFET (metal oxide field effect transistor) for mobile applications. The power MOSFET is a fast switching device in fields with low voltage(<100 V) such as mobile application. Moreover, the power MOSFET is a major carrier device that is not minor carrier accumulation when the device is turned off. We performed process and device simulation using TCAD tools such as MEDICI and TSUPREM. The electrical characteristics of the proposed trench gate power MOSFET such as breakdown voltage and on resistance were compared with those of the conventional power MOSFET. Consequently, we obtained breakdown voltage of 100 V and low on resistance of $130m{\Omega}$. The proposed power MOSFET will be used as a switch in batteries of mobile phones and note books.

• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06c
• /
• pp.26-30
• /
• 2010

현재 연구자들은 연구기획, 협업 연구자 선정 및 특정 분야의 전문가 정보를 찾기 위해서 많은 시간과 노력을 기울이고 있다. 본 논문에서는 이러한 연구자들의 노력을 줄여주기 위해서 연구자 중심의 학술 정보 분석 서비스에 대해 설명하고자 한다. 본 논문에서는 BiomedExperts, Authoratory, ResearchGATE, Academic Search와 같은 기존 사이트에서 제공되는 연구자 중심 학술 정보 서비스와 OntoFrame S3의 연구자 중심 학술 정보 분석 서비스에 대해 간단하게 살펴보고, 각 사이트에서 공통으로 지원하는 4가지 서비스-연구자의 기본 정보, 연구자의 연구 동향 정보, 연구자 네트워크, 연구자의 논문 정보 서비스-에 대해 비교, 분석하고 주요 기능적 특징에 대해 살펴본다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2019.05a
• /
• pp.296-298
• /
• 2019

개방과 협력의 시대로 불리는 현재, 학문분야의 융합과 소통은 이미 오래전부터 강조되었던 가치다. 그러나 현실적으로 오랜 세월 전문 영역의 틀로써 명확히 분리되어왔던 학자들이 다른 영역의 연구자들과 자유롭게 협업 및 교류하는 상황은 쉽게 일어나기 어렵다. 이러한 문제에 대한 해결책으로서 본 연구는 온라인 네트워크 플랫폼에 주목하였다. 특히 학문 전 분야의 전문 연구자들을 연결하는 세계적인 플랫폼인 리서치게이트의 사례를 통해 사용자 동인을 확인해보고자 하였다. 이를 위해 본 연구에서는 국내 리서치게이트 이용자들에 대한 사용성 평가 설문 및 FGI를 계획하였다. 본 연구의 결과는 국내 연구자들을 중심으로 한 전문연구자 정보 네트워크 플랫폼 개발 방향에 대해 현실적인 시사점을 제시할 것으로 기대한다.

• Journal of architectural history
• /
• v.30 no.2
• /
• pp.19-28
• /
• 2021

The purpose of this study is to research about the construction of Chiseong around the Heunginjimun Gate area in the 18th century. the conclusions derived from the historical evidence of the number, location, size, and form, and construction method of Chiseong was as follows. First, the Chiseong(Square-shaped lookout) of Hanyangdoseong was built in the 29th year of King Yeongjo(1753) and can be found in the national record. Five sites of the Chiseong are currently identified. It is assumed that the Foru was installed on top of some of the Chiseongs. Second, Chiseong was destroyed sequentially in the first half of the 20th century. Third, Chiseong is a rectangular in shape and six are constructed. Fourth, Sixth Chiseong could figure out through Hengryeopungsokdo, the drawing of Jeong Seon.