• Title/Summary/Keyword: CCI

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Performance Analysis of IMT-2000 System with Improvement Rake Receiver (개선된 레이크 수신기를 채용하는 IMT-2000 시스템의 성능 분석)

  • 소준영;우병훈;강희조
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2000.11a
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    • pp.39-43
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    • 2000
  • 본 논문에서는 IMT-2000 시스템에 대한 제안된 표준안을 기초로 송수신 시스템을 구성하여 광대역 무선채널 환경 및 다양한 시스템 운용환경에서 시스템의 성능을 분석한다. 수신 성능의 개선을 위하여 CCI(Co-Channel Interference) Canceller와 Rake 수신기를 혼합하여 기존의 Rake 수신기에서 제거할 수 없었던 자기 간섭(Auto Interference)을 제거하는 새로운 Rake수신기를 제안하였다. 또한 다중 경로 페이딩 모델로는 ITU-R M.1225에서 제시된 모델을 적용하였다. 성능 분석 결과, 상대적으로 작은 지연 확산을 가지는 채널 A가 중간 지연 확산을 가지는 채널 B보다 수신성능이 양호함을 알 수 있었으며, 채널 A와 B에 관계없이 제안된 레이크 수신기를 채용하였을 경우 자기 간섭의 제거 효과로 인해 수신성능이 기존의 레이크 수신기를 채용하였을 경우에 비해 향상됨은 알 수 있었다. 또한 간섭제거기와 제안된 레이크 수신기를 직렬로 연결한 수신기를 채용하였을 경우 다중접속간섭을 효과적으로 제거할 수 있었으며, 수신성능의 차이는 채널 환경이 양호할수록, $E_{b/}$N/ sub o/값이 커질수록 차이가 커짐을 알 수 있었다.다.

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Conference Sketch - 'ESCO 우수투자사례 발표회' 현장을 가다

  • 에너지절약전문기업협회
    • The Magazine for Energy Service Companies
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    • s.67
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    • pp.28-33
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    • 2010
  • 지난 10월 13일 오후 2시, 서울 삼성동 코엑스 홀에서 'ESCO 우수투자사례 발표회'가 열렸다. 지식경제부가 주최하고, 에너지관리공단이 주관하며 ESCO 협회의 후원으로 ESCO 우수투자사례 발표회가 치러졌다. 이번 행사는 우수 ESCO 수여식과 함께 공공기관과 민간부문, 산업체 등의 에너지사용자에게 ESCO 투자사례 홍보 및 정보제공을 도모하기 위해 마련되었다. 올해 우수 ESCO 기업으로 삼성에버랜드(주)와 LIG엔설팅(주)이 선정되었으며, 우수 ESCO 수여식을 시작으로 이재우 실장(에너지관리공단 자금운용실)의 인사말이 이어졌다. 이재우 실장은 인사말을 통해 "2010년 1,350억 원이었던 ESCO지원자금이 2011년에는 6,000억 원 규모로 크게 확대되고, ESCO사업이 더욱 성장할 수 있도록 정책적 지원이 이뤄질 것"이라고 전했다. ESCO 우수투자사례 발표에 앞서, 이희송 소장(클린턴 재단)은 '해외 ESCO 사업 추진현황'과 관련하여 클린턴 재단(CCI)의 에너지효율 건물개조 프로그램을 소개하였다. 이어 삼성에버랜드(주)의 이명진 차장이 산업부문 에너지절약 투자사례인 (주)케이피케미칼 폐열회수 열교환장치와 제일모직(주) 증기재압축장치를 발표하였으며, LIG엔설팅(주)의 김영준 차장이 산업체 공정개선 투자사례인 카프로 제3공장 락탐증발농축시설 교체 설치에 대한 ESCO 우수사례를 소개했다.

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Improvement contract sum adjustment method caused by price fluctuation (물가변동에 의한 계약금액 조정방안 개선 기초연구)

  • Cho Hun-Hee;Seo Jang-Woo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • v.y2004m10
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    • pp.83-86
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    • 2004
  • Index adjusted ration method has been widely utilized in public construction secter for contract sum adjustment by price fluctuation. In this method. the Production Price Index are used for calculating the base ratio. but the PPI can't reflect the property of construction project in respect of the selected item and weight structure. In this research we prove the problem of using the index adjusted ration method in contract sum adjustment by price fluctuation. and improve it by using the construction cost index. which has the property of construction project. And the result. we figure out the difference between the PPI and CCI by $6.7\%$ in maximum value.

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Performance Analysis of DS-CDMA/TDMA Frequency Sharing System in Radio Multimedia Communication (무선 멀티미디어 통신에서 DS-CDMA/TDMA 주파수공용 시스템의 성능 분석)

  • 김숙영;강희조;조성언
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.686-690
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    • 2003
  • 직접 확산 부호 분할 다원 접속 (Direct Sequence Code Division Multiple Access : DS-CDMA) 시스템과 시분할 다원 접속 (Time Division Multiple Access : TDMA) 시스템을 동일 주파수 대역에서 중첩되어 전송할 때 DS-CDMA 신호에서의 TDMA 신호의 협대역 간섭이 문제된다. 본 논문에서는 DS-CDMA 신호의 협대역 간섭(narrowband interference : NI)를 제거하는 방법으로서 노치필터를 이용해서 협대역 간섭파 제거법을 제안하고, 간섭제거기(CCI canceller)를 이용해서 다중접속간섭을 제거하여 DS-CDMA 신호의 성능을 개선한다. 본 논문은 잡음, 다중접속 간섭 및 협대역 간섭환경에서 DS-CDMA 신호와 TDMA 신호의 주파수 공용 시스템에 적용할 때의 성능을 분석하였다.

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Minimizing the Co-channel Interference in WLAN Systems

  • Zhou, Feng;Kim, Jeong-Ho;Choi, Yong-Hoon;Park, Su-Won;Rhee, Seung-Hyong
    • Proceedings of the Korean Information Science Society Conference
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    • 2011.06d
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    • pp.325-327
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    • 2011
  • With increasing competition of the radio spectrum, co-channel interference(CCI) is becoming the dominant interference and may seriously degrade the communication performance of wireless stations. Co-channel interference, when not minimized, increases the probability of packet collisions which cause diminished system capacity. The work presented in this paper investigates the effect of co-channel interference, which is studied in a co-channel interference scenario. To minimize the co-channel interference, a new MAC protocol is proposed in this paper.

Effects of Administration of CCl$_{4}$ on Liver Function in Rats 1. Clinical Signs and Blood Chemical Values (사염화탄소(CCI$_{4}$)의 투여가 쥐의 간기능에 미치는 영향 1. 임상증상 및 혈액화학치)

  • 강정부;이은석;허주헝
    • Journal of Veterinary Clinics
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    • v.14 no.2
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    • pp.268-272
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    • 1997
  • This study was performed to estimate the clinical signs and biochemical para meters of indicator on acute hepatic injury induced by the administration of CCl$_{4}$ in rats. Minor behavioral changer brittleness of skin hair and decreased volume of water and food intake were observed in rats after 2 hours of $CCl_{4}$ administration compared to control group. Concentration of serum albumin has shown lower than that of control group. However concentration of total bilirubin has shown higher than that of control group. As times go onto serum LDH activity was significantly increased compared to control Broup. Serum CPK activity hasn't shown change compared to control group. Passive hemagglutination that of afetoprotein was shown negative reaction in all the treatment groups and control group.

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Application of Nonuniform Weighted Distribution Method to Enhancing Signal Processing Effect of Subband Spatial-Temproral Adaptive Filter

  • Vuong Le Quoc;Tai Pham Trong
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.97-102
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    • 2004
  • The very complicated proplem in spatial processing is effects of phading (Multipath and Delay Spread) and co-channel interference (CCI). The phading is one of principal causes, that form inter-symbol interference (ISI). Spatial-Temproral Adaptive Filter (STAF) has been taken as a solution of this problem, because it can suppress both these types of interference. But the performance of STAF exposes some elemental limitations, in which are the slow convergence of adaptive process and computational complexity. The cause of this is that, STAF must treat a large quantity of information in both space and time. The way that master these limitation is a use of Subband Spatial-Temproral Adaptive Filter (SSTAF). SSTAF reduce computational complexity by pruning off samples of signal and thus it lost some information in time. This draw on attennation of output SINR of SSTAF. The article analyse a optimal solution of this problem by introducing SSTAF with nonuniform weighted distribution.

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Dynamic Channel Allocation Algorithm for Co-channel Interference Avoidance in Multi-cell OFDMA Systems (OFDMA 다중 셀 환경에서 동일 채널 간섭을 피하기 위한 동적 자원 할당 기법)

  • Lee, Je-Min;Seo, Woo-Hyun;Han, Seung-Yeop;Kim, Seong-Tae;U, Jung-Jae;Hong, Dae-Sik
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.153-154
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    • 2006
  • We propose the dynamic channel allocation (DCA) algorithm for multi-cell OFDMA systems to avoid co-channel interference (CCI). The proposed algorithm is utilized not in a centralized, but in a distributed manner which reduces complexity. The simulation results confirm that the number of overlapping allocated subcarriers is reduced and the average SINR of a sub-carrier is increased by this algorithm.

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Curcumin Attenuates Chronic Constriction Nerve Injury-Induced Neuropathic Pain in Rats (Curcumin의 신경병증성 통증 억제효과)

  • Kim, Chae-Eun;Park, Eun-Sung;Jeon, Young-Hoon
    • Korean Journal of Medicinal Crop Science
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    • v.16 no.3
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    • pp.183-187
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    • 2008
  • Nerve injury can lead to neuropathic pain, which is often resistant to current analgesics and interventional therapeutic methods. Extracellular signal-regulated kinase (ERK) plays important role in the induction of neuropathic pain. We explored the antinociceptive effect of curcumin and its effect on ERK in the spinal cord in the neuropathic pain model of rats induced by chronic constriction injury (CCI) of the sciatic nerve. In injured rats, mechanical allodynia, which is one of characteristics of neuropathic pain developed and the activation of ERK in spinal cord significantly increased compared with control group. However, administration of curcumin (50 mg/kg/day p.o) for 7 days started from one day before the injury prevented the development of mechanical allodynia and increase of ERK phosphorylation. These results indicate that curcumin can be a new therapeutic agent in the treatment of neuropathic pain.

Effect of Cyperi Rhizoma on $CCI_4$ Induced Hepatotoxicity and Lipid Peroxidation (향부자 분획물의 사염화탄소로 유도된 간장해 및 지질과산화에 미치는 영향)

  • Kim, Tae-Hee;Park, Ji-Young
    • Korean Journal of Pharmacognosy
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    • v.28 no.4
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    • pp.185-191
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    • 1997
  • Cyperus rotundus L. (Cyperaceae) has been used as an analgesic and antiiflammatory agent and in the treatment of menstrual disorder in folk remedies. Cyperi Rhizomata, processed and unprocessed, were extracted with methanol and fractionated with petroleum ether, chloroform. Butanol, water. The effect of unprocessed Cyperi Rhizoma and processed Cyperi Rhizoma on $CCl_4$ induced lipid peroxidation and hepatotoxity have been tested in rats. BuOH. Water fractions of unprocessed Cyperi Rhizome enhanced the inhibition of antilipid peroxidative effects in liver lipid. In chemical parameters obtained from serum analysis. Butanol fraction of unprocessed Cyperi Rhizoma showed significant decrease in hepatotoxicity. In result, unprocessed Cyperi rhizoma has significant antilipid peroxidative effect and hepatoprotective activity.

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