• 한국멀티미디어학회논문지
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• 제16권7호
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• pp.862-869
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• 2013

In order to support a cell-independent traffic asymmetry, the conventional TDD system cannot avoid crossed time slot (CTS) interference. Moreover, the TDD/FDD hierarchical overlay cellular systems is taken into account as a generally accepted cell model in a heterogeneous radio environment. In this paper, we propose an interference resolving radio resource allocation technique in a TDD-OFDMA cellular system that overlays a FDD-CDMA cell. In our proposed scheme, we exploit under-used FDD-CDMA uplink resource by TDD mobile abiding by a region based time slot(TS) allocation which in turn mitigates CTS interference considerably. It is demonstrated that combined with under-used resource utilization scheme based on mobile's location, the proposed technique can reduce CTS interference considerably and support the asymmetric traffic in TDD system.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.521-521
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• 2013

Collective Thomson scattering (CTS) system is being developed in KAERI based on high power gyrotrons. CTS is a promising diagnostic method to measure fast ion distributions and potentially the fusion product alpha particles in magnetically confined plasmas. By utilizing millimeter-waves from high power gyrotrons as a probing beam, spatially and temporally resolved 1-D ion velocity distributions can be obtained from the scattered radiation with less scattering geometrical constraints. The pulse modulation of gyrotrons enables to separate scattering signal from ECE background noises. The feasibility was assessed with the calculation of spectral density functions under the condition of KSTAR plasmas. Further CTS system requirements are also discussed.

• 항공우주시스템공학회지
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• 제14권5호
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• pp.49-57
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• 2020

KC-100은 국토교통부로부터 민간형식인증이 완료되었고 현재 국토교통부 사업의 일환으로 무인비행기로 개조 개발 중이다. KC-100을 무인화 개조한 무인비행기 시스템(CTsUA System)은 고중량의 임무장비 탑재 및 장시간 비행 임무 수행 등이 가능하도록 개발하고 있다. 본 연구는 CTsUA System의 운용개념에 기반한 임무형상을 수행하기 위하여 각 단계별로 항공기 중량, 대기속도, 비행고도, 필요마력, 연료소모량 등 다양한 파라미터에 대하여 분석하는 과정과 결과에 대한 것이다. 최대이륙중량 3,600lbs(1,633kg)를 유지하기 위해서는 무인화시스템을 위한 적용 장비의 중량은 80lbs(36kg) 이하로 유지해야 하는 것으로 분석되었다.

• 한국항공우주학회지
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• 제33권10호
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• pp.75-81
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• 2005

낙하물 및 로켓 단분리 등과 같은 비행체 분리물의 궤적을 모사하기 위해 사출, 격자 및 CTS 시험과 같은 풍동시험 기법이 많이 사용된다. 본 논문에서는 3단형 과학로켓 개발 시 사용된 격자 및 CTS 시험 기법 및 대표적인 결과를 소개하였다. 시험에 사용된 풍동은 ONERA S2MA이며 마하수 2.0과 2.8에 대해 13개의 분리 궤적을 시험하였다. 시험 결과는 분리장치를 최적화기 위한 데이터베이스로 활용되었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.123-124
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• 2007

In this paper a comparison of several coarse time synchronization(CTS) algorithms for OFDM is presented. The goal of a CTS is to achieve a timing estimate that avoids IST in the receiver. Five coarse timing estimation algorithms are examined and their performances are compared associated with hardware complexity. Simulations has been performed for DVB-T 2K system in thee different channels.

• Current Photovoltaic Research
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• 제3권4호
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• pp.135-139
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• 2015

$Cu_2SnS_3$ (CTS) based thin film solar cells (TFSCs) are of great interest because of its earth abundant, low-toxic and eco-friendly material with high optical absorption coefficient of $10^4cm^{-1}$. In this study, the DC sputtered precursor thin films have been sulfurized using rapid thermal annealing (RTA) system in the graphite box under Ar gas atmosphere for 10 minute. The systematic variation of sulfur powder during annealing process has been carried out and their effects on the structural, morphological and optical properties of CTS thin films have been investigated. The preliminary power conversion efficiency of 1.47% with a short circuit current density of $33.9mA/cm^2$, an open circuit voltage of 159.7 mV, and a fill factor of 27% were obtained for CTS thin film annealed with 0.05g of S powder, although the processing parameter s have not yet been optimized.

• Journal of Microbiology and Biotechnology
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• 제3권1호
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• pp.1-5
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• 1993

The gene for mannose enzyme II of phosphoenolpyruvate-dependent phosphotransferase system from Corynebacterium glutamicum KCTC 1445 was cloned into Escherichia coli ZSC113 using plasmid pBR 322. The recombinant plasmid, designated pCTS3, contained 2.2 kb DNA fragment, and the physical map of the cloned DNA fragment was determined. The E. coli ptsM ptsG mutant transformed with pCTS3 restored glucose and mannose fermentation ability, and grew well on these sugars as the sole carbon source in the minimal medium. The transform ant harboring pCTS3 showed a PTS-mediated repression of growth on maltose by mannose analogue, 2-deoxyglucose. The specificity of the response to 2DG therefore indicates that the cloned DNA fragment carries mannose enzyme II gene.

• 전기학회논문지P
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• 제57권4호
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• pp.431-436
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• 2008

We have extended an absolute evaluation method to obtain the ratio error and phase displacement of a current transformer (CT) up to primary current of 40,000 A by measuring four parameters of equivalent circuit in CT. The method was applied to CTs under test with the current ratios in the range of 5,000 A / 5 A - 40,000 A / 5 A. The ratio error and phase displacement of the CTs under test obtained in this study are consistent with those measured at the national institutes in Canada and Germany using the same CTs under test within an expanded uncertainty (k = 2) in the overall current ratios.

• ETRI Journal
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• 제31권1호
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• pp.83-85
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• 2009

Compared with unicast, multicast over wireless ad-hoc networks do not support reliability due to their inability to exchange request-to-send/clear-to-send (RTS/CTS) and ACK packets with multiple recipients. Although several media access control (MAC) layer protocols have been proposed to provide reliable multicast, these introduce additional overhead, which degrades system performance. A novel MAC protocol for reliable wireless multicast is proposed in this paper. By adapting orthogonal frequency division multiple access characteristics in CTS and ACK packets, the protocol achieves reliability over wireless multicast with minimized overhead.

• 해양환경안전학회지
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• 제21권1호
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• pp.72-82
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• 2015

본 논문에서는 기존의 POM(Princeton Ocean Model) WAD(Wetting and Drying) 모형을 연안역에서 조석조류의 계산에 적합하도록 개경계에서 조석조화상수를 입력하여 사용할 수 있도록 하였고, CTS(Computing Time Saving) 기법을 도입하여 계산시간을 단축할 수 있도록 개선하였다. 이와 같이 수정된 모형은 장방형 내만에 하나의 절점을 갖는 정상파에 대한 해석해 실험과 유속 및 열확산에 대한 수리모형 실험결과와 비교하여 좋은 결과를 얻었다. 그리고 간석지가 발달한 광양만의 현지해역에 이 CTS 기법을 적용하여 계산시간이 39.4% 단축되는 결과를 얻었다.