• Title/Summary/Keyword: 역구조 결함

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A Study on Low Phase Noise PLL Design for Ultra Wideband (초 광대역에 적용 가능한 저위상 잡음 PLL 설계에 관한 연구)

  • Shim, Yong-Sup;Lee, Il-Kyoo;Lee, Yong-Woo;Oh, Seung-Hyeub
    • Journal of Satellite, Information and Communications
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    • v.5 no.1
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    • pp.17-21
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    • 2010
  • In this paper, we have introduced a new way to design low phase noise PLL which can apply to the Ultra wideband as meeting performance requirements based on structure improvement, circuit supplement, upgraded design method. Before development of the PLL, we simulated spectrum power, phase noise, harmonic characteristic by using ADS(Advanced Designed System). And, we compared result between measurement and simulation. Finally, we confirm a satisfying result which meet performance requirements between required standard and measured value. It will be useful for transceiver of service which operate in Ultra wideband.

직할시공제 시행, 도급구조 개선효과 기대

  • 대한설비건설협회
    • 월간 기계설비
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    • s.226
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    • pp.38-41
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    • 2009
  • 보금자리주택 건설 등에 관한 특별법이 지난 4월 21일 시행에 들어갔다. 이 법에 따라 연간 계획물량의 5%에 적용되는 직할시공제가 대한주택공사(사장 최재덕)에서 시행될 예정이다. 대한설비건설협회는 직할시공제가 시행되기 까지 많은 노력을 기울여 왔다. 대한 설비건설협회는 대통령을 비롯하여 정부와 국회, 건설선진화위원회 등에 도급구조의 개선을 건의한 결과 시법시행이지만 직할시공제가 도입되는 성과를 거두었다. 시범시행되는 3년 동안 설비건설업계는 고품질의 시공을 통해 직할시공제 도입 효과를 입증해야 할 과제를 안고 있다. 본지는 직할시공제가 어떤 것이고 적용계획이 무엇인지, 또 직할시공제가 시공되기까지 대한설비건설협회의 역할 등을 알아본다.

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신월성원전 건설 중 해수침수사고와 해결과정의 고찰

  • Lee, Byeong-Il;Jeong, Jin-Uk
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2009.11a
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    • pp.39-40
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    • 2009
  • 2009년 4월 29일 신월성원전 건설현장에 해수가 유입되어 건설 중에 있던 구조물과 건축 재료가 해수에 침수되는 사고가 발생하였다. 이 후 지역의 대표들이 신월성침수사고 조사위원회를 구성하여 침수된 구조물의 안전성과 보수가 필요한 부분을 정량적으로 평가하고 그 결과를 발표하였다. 본 논문에서는 침수사고의 개요와 조사위원회의 구성과정 및 활동 그리고 조사위원회의 의미 등을 살펴보고 이 때 월성원전감시기구의 역할 등을 고찰하여 원전주변지역 주민의 의식변화와 이에 따른 관련기관의 역할을 기술하였다.

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Inter-regional Income Inducement and Income Transfer Analysis Using Korean Regional Input-Output Tables (지역산업연관표를 이용한 지역 간 소득유발과 소득전이 분석)

  • Kwon, Tae Hyun
    • Economic Analysis
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    • v.27 no.3
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    • pp.61-96
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    • 2021
  • This study is to structurally examine the regional income disparity in Korea. It measures the regional income inducement by household consumption expenditure per unit income, and the regional interdependency of income using 2005 and 2015 Regional Input-Output Tables of 16 provincial regions of Korea. The results are as follows. Firstly, the income inducement by consumption expenditure per unit income decreased overall, mainly due to the decrease in the income inducement of other regions than due to that of their region. Secondly, in many regions, the inter-relational income dependency per unit income decreased also, this too, mainly due to the decrease in the income transfer to other region. And, the income inducement effects of consumption expenditure per unit income of Seoul and Gyeonggi, which occupy a large portion of the Korean economy, were lower than that of other regions, but took the largest portion of income inducements generated by other regions as well as by themselves and absorbed the income transfers from other regions the most. The higher income inducement and income absorption in Seoul and Gyeonggi by consumption expenditure of other regions were mainly because of the high share in service of their consumption structure, the progress in tertiarization of their industrial structure, and the high wage portion. These results also mean that viewed from the regional interdependency of income, the income of Seoul and that of Gyeonggi are highly dependent on the income of other regions. Especially, Gyeonggi which leads the overseas exports of high-tech based manufactured products, has other external factors that contribute to their high income inducement, whereas, Seoul which shows high income absorption using its inter-relations with other domestic regions based on the services, has an income-generating structure that is sensitive to other regions' economic situation. Amid overall declines in regional income inducements and in income transfers, and continuing concentrations into Seoul and Gyeonggi regions, to alleviate the regional disparity, the regional industry policies should, rather than benchmarking the policies of the two concentrated regions, enhance their own inter-regional relationships by strengthening the comparative advantage of their regionally specialized industry.

Interface Functional Materials for Improving the Performance and Stability of Organic Solar Cell (유기태양전지의 효율 및 수명 향상을 위한 기능성 계면 소재 연구)

  • Hong, Kihyon;Park, Sun-Young;Lim, Dong Chan
    • Applied Chemistry for Engineering
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    • v.25 no.5
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    • pp.447-454
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    • 2014
  • Organic solar cells (OSCs) have intensively studied in recent years due to their advantages such as cost effectiveness and possibility of applications in flexible devices. In spite of the high power conversion efficiency (PCE) of 10 %, the OSCs still have a draw back of their low environmental stability due to the oxidization of aluminum cathode and etching of transparent conducting oxide as electrode. To solve these problems, the inverted structured OSCs (I-OSCs) having greatest potential for achieving an improvement of device performances are suggested. Therefore, there are a lot of studies to develope of interface layer based on organic/inorganic materials for the electron transport layer (ETL) and passivation layer, significant advancements in I-OSCs have driven the development of interface functional materials including electron transport layer. Recent efforts to employing 2D/3D zinc oxide (ZnO) based ETL into I-OSCs have produced OSCs with a power conversion efficiency level that matches the efficiency of ~9 %. In this review, the technical issues and recent progress of ZnO based ETL in I-OSCs to enhancement of device efficiency and stability in terms of materials, process and characterization have summarized.

Linearization scheme of serially connected EA modulator for broadband microwave optical transmission (광대역 마이크로파 광전송을 위한 전계흡수 광변조기 직렬연결 변조방식의 선형성)

  • 손성일;한상국
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.11B
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    • pp.1841-1846
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    • 2000
  • 광대역 마이크로파 신호의 광전송시 변조과정에서 발생되는 상호잡음 성분의 억제를 위한 다단 직렬구조의 전계흡수 광변조기를 이용한 선형화 방법을 제안하였고 이론적으로 고찰하였다. 바이어스 전압에 따른 신호의 위상 반전이 발생되는 것을 이용하여 두 개의 서로 다른 바이어스 전압과 입력 마이크로파 신호의 전력 차를 이용하여 광대역 시스템의 성능을 좌우하는 IMD2와 IMD3를 동시에 억압시킬 수 있었다. 모의실험을 통하여 최적의 동작조건을 찾은 결과 35dB의 IMD2 억제와 50dB의 IMD3를 동시에 억압시킬 수 있었으며 이에 따라서 약 15dB의 동작영역의 증가를 얻을 수 있었다.

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Study on Usage-behavior of Fixed and Wireless Internet and Needs of Mobile Broadband (유무선 인터넷 이용행태와 모바일 브로드밴드(Mobile Broadband) 니즈 분석)

  • Park, Jong-Hyun;Kim, Moon-Koo;Lee, Sun-Mi;Park, Hee-Jin
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.10d
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    • pp.549-552
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    • 2006
  • 국내 유무선 인터넷은 세계 시장과 통신트랜드를 주도할 정도로 이용자 규모, 서비스 다양성, 서비스 수용성 측면에서 커다란 성과를 나타내며 이는 선순환 구조를 통해 단말기, 장비, 콘텐츠 산업의 경쟁력을 강화시키는데 기여하고 있다. 또한 국내 통신시장은 와이브로와 HSDPA로 대표되는 광대역 무선인터넷 시대를 선도할 것으로 기대되고 있다. 본 글에서는 전국 일반인을 대상으로 시장조사 결과를 바탕으로 유무선 인터넷의 이용행태를 파악하고 광대역 무선인터넷에 대한 니즈를 탐색하고자 하였다. 분석결과, 국내 유무선 인터넷 시장은 10~20대의 학생층뿐만 아니라 30대 이상의 화이트 칼라로 이용층으로 확대되며 이 계층이 광대역 무선인터넷의 핵심 이용자군으로 잠재력을 지닌 것으로 나타났다.

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The Design of the Broadband Sleeve Monopole Antenna using Loading Coil (로딩 코일을 이용한 광대역 슬리브 모노폴 안테나의 설계)

  • 최광제
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.3
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    • pp.250-256
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    • 2002
  • In this paper, a broadband sleeve monopole antenna using a loading coil in sleeve is proposed. The center frequency of the proposed antenna is 1,990MHz. The antenna of the proposed structure has the same of the single sleeve monopole antenna, except for using the coil instead of the inner conductor in sleeve. As a result, it is found that the bandwidth is 1.239~2.154 GHz(above 53.9 %) for $S_{11}=-10\;d B$(VSWR<2), and the antenna impedance is good for a communication system and feeder which the impedance has 50 Ω.

Design and Fabrication of Wideband Probe for Efficient Near Field Measurement (근역장의 효율적 측정을 위한 광대역 프로브의 설계 및 제작)

  • Kim Joung-Myoun;Moon Jung-Ick;Yun Je-Hoon;Jeon Soon-Ik;Kim Nam
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.9 s.112
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    • pp.836-844
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    • 2006
  • In this paper, we designed and fabricated the wideband probe with double ridged waveguide for Near-field Measurement. An exponential taper ridge in the rectangular waveguide was implemented for wideband impedance matching. It has wideband characteristics and its measured impedance bandwidth ratio is approximately 2.2:1 from 8.2 GHz to 18 GHz for $VSWR\leq2.2$. It maintains about the same radiation pattern over the entire bandwidth and has more than 4.5 dBi peak radiation gain. Our designed probe was applied to near-field measurement. A good agreement has been found between simulated and measured results.

A 0.18-μm CMOS Low-Power and Wideband LNA Using LC BPF Loads (광대역 LC 대역 통과 필터를 부하로 가지는 0.18-μm CMOS 저전력/광대역 저잡음 증폭기 설계)

  • Shin, Sang-Woon;Seo, Yong-Ho;Kim, Chang-Wan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.1
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    • pp.76-80
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    • 2011
  • This paper has proposed a 3~5 GHz low-power and wideband LNA(Low Noise Amplifier), which has been implemented in a 0.18-${\mu}m$ CMOS technology. The proposed LNA has basically the noise-cancelling topology to achieve a balun-function, wideband input matching, and relative low noise figure. In addition, it has utilized a 2nd-order LC-band-pass filter(BPF) as its output load to achieve higher power gain and lower noise figure with the lowest dc power consumption among previously reported works. The proposed amplifier consumes only 3.94 mA from a 1.8 V supply voltage. The simulation results show a power gain of more than +17 dB, a noise figure of less than +4 dB, and an input IP3 of -15.5 dBm.