• 한국통신학회논문지
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• 제33권4A호
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• pp.352-360
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• 2008

최근 IEEE (Institute of Electrical and Electronics Engineers) 802.15.4a TG (Task Group)에서는 저소비, 저전력 뿐만 아니라 다수개의 피코넷이 공존하는 즉, SOPs (simultaneously operating piconets) 환경하에서 거리 인지가 가능하도록 규정하고 있으며 거리인지 (ranging)의 서비스에 따라 Ternary 코드를 이용한 coherent/non-coherent 방안이 표준으로 채택되었다. 그러나 표준안에서 제시된 최소의 펄스 간 간격(Pulse Repetition Interval; PRI)은 채널의 최대 초과 지연 aximum Excess Delay; MED) 보다 좁아 펄스 간 간섭 (Inter-Pulse Interference; IPI) 문제가 발생되어 DS(Direct Sequence) 기반의 추정기법으로는 부정확한 최초 도착 시간(Time Of Arrival; TOA)을 얻게 된다. 따라서 본 논문에서는 IPI을 줄이면서 고정밀 TOA를 추정하기 위한 비주기적 펄스 전송 (non-periodic transmission; NPT) 패턴 기법을 제안한다. 수신단은 저속 무선 개인 영역 네트워크의 모티브를 고려하여 에너지 검출을 이용한 non-coherent 기반의 수신 구조로 구성하였다. TOA 정보는 슬라이딩 상관처리 후 역 탐색 구간 (Search Back Window; SBW)을 두어 오차를 감소시키고 사전 정해진 임계치를 이용하여 얻기 된다. 제안된 펄스 패턴 기법에 대한 성능을 검증하기 위해서 BEE 802.15.4a TG에서 제시한 두 가지 채널 모델을 적용하였고 시뮬레이션 결과로부터 제안된 기법이 다수개의 피코넷이 공존하는 다중 경로 환경에서 일반적인 기법보다 성능이 개선됨을 확인하였다.

• 대한수학회지
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• 제53권1호
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• pp.187-199
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• 2016

The r-ary number sequences given by $$(b^{(r)}_n)_{n{\geq}0}=\Large{\frac{1}{(r-1)n+1}}(^{rn}_n)$$ are analogs of the sequence of the Catalan numbers ${\frac{1}{n+1}}(^{2n}_n)$. Their history goes back at least to Lambert [8] in 1758 and they are of considerable interest in sequential testing. Usually, the sequences are considered separately and the generalizations can go in several directions. Here we link the various r first by introducing a new combinatorial structure related to GR trees and then algebraically as well. This GR transition generalizes to give r-ary analogs of many sequences of combinatorial interest. It also lets us find infinite numbers of combinatorially defined sequences that lie between the Catalan numbers and the Ternary numbers, or more generally, between $b^{(r)}_n$ and $b^{(r+1)}_n$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1965-1966
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• 2008

The manipulation of Boolean functions is a fundamental part of computer science, and many problems in the design and testing of digital systems can be expressed as a sequence of operations. It is mainly a paper of our research on the techniques of Boolean function manipulation using Binary Decision Diagram(BDDs) and their applications for VLSI CAD System. In many practical applications related to digital system design, it is a basic technique to use ternary-valued functions. In this paper, we discuss the methods for representing logical values.

• 한국통신학회논문지
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• 제21권4호
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• pp.1027-1037
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• 1996

This paper presents an impulse response of the multi-path channel using KS-GCR(Korean Standard Ghost Cancel Reference) signal. Using the property of the KS-GCRsignal, we can get the impulse response of the multi-path channel from circular cross correlation of the received DS-GCR signal and the orginal KS-GCR ternary sequence. Therefore impulse response of the multi-path channel can be used to design the the ghost cancellation filter if it is designed to have inverse characteristics of multi-path channel. This paper shows that the ghost occurred from the multi-path channel can be cancelled by using the impulse response and preceding ghost cancellation algorithm.

• BMB Reports
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• 제38권2호
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• pp.225-231
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• 2005

Acid-labile subunit (ALS) is a component of the 150-kDa insulin-like growth factor-binding protein-3 (IGFBP-3) complex, which, by sequestering the majority of IGFs-I and -II and thereby prolonging the half-life of them in plasma, serves as a circulating reservoir of IGFs in mammalian species. A pGEX-2T plasmid and a baculovirus expression constructs harboring a coding sequence for glutathione-S transferase (GST)-porcine ALS (pALS) fusion protein were expressed in BL21(DE3) E. coli and Sf9 insect cells, respectively. The expressed protein was purified by glutathione or Ni-NTN affinity chromatography, followed by cleavage of the fusion protein using Factor Xa. In addition, pALS and hIGFBP-3 were also produced in small amounts in the Xenopus oocyte expression system which does not require any purification procedure. A 65-kDa pALS polypeptide was obtained following the prokaryotic expression and the enzymatic digestion, but biochemical characterization of this polypeptide was precluded because of an extremely low expression efficiency. The baculovirus-as well as Xenopus-expressed pALS exhibited the expected molecular mass of 85 kDa which was reduced into 75 and 65 kDa following deglycosylation of Asn-linked carbohydrates by Endo-F glycosidase, indicating that the expressed pALS was properly glycosylated. Moreover, irrespective of the source of pALS, the recombinant pALS and hIGFBP-3 formed a 130-kDa binary complex which could be immunoprecipitated by anti-hIGFBP-3 antibodies. Collectively, results indicate that an authentic pALS protein can be produced by the current expression systems.

• 한국위성정보통신학회논문지
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• 제6권2호
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• pp.125-130
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• 2011

본 논문은 T-DMB 재난방송에서 데이터 전송 기술 향상을 위해 확산코드를 이용하여 각 코드들의 자기상관특성(Auto Correlation Feature) 성능을 비교해 보았다. 일반적으로 DMB와 같은 무선 이동 통신 환경은 수신기에서 송신기의 식별 과정에서 발생하는 인접코드 간섭(Inter Code Interference) 및 다중경로 간섭(Multi-Path Interference)이 일어난다. 이러한 문제점을 해결하기 위해서 확산코드 기법을 이용하여 비화 특성을 개선시킬수 있고, 코드의 주기를 조절하여 가변시킬수가 있어 신호처리 다분야에서 활용 할 수가 있다. 이에 본 논문은 직교성이 우수한 Golay코드와 Kasami코드, ZCD(Zero Correlation Duration)코드에 성능을 비교하는 연구를 하였다.

• 한국제4기학회지
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• 제11권1호
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• pp.57-68
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• 1997

Climatic change of the late-Quaternary period has been record-ed in the loess deposits of the central Great plains and the record of such change is extractable using a number of approaches and parameters. The stratigraphy of loess deposits which have been investigated on Fort Riley exhibits the same sequence of loess units and intercalated buried soils as is found elsewhere in the re-gion but adds detail unique to the reservation Upland late-Qua-ternary composite stratigraphy preserved on the reservation con-sists of the basal Sangamon soil of the Last interglacial(c. 120-110ka), Gilman Canyon Formation(c. >40 -20ka), Peoria loess(c. 20 -10ka) Brady soil(c. 11 -10ka) Bignell loess(c. 9-\ulcornerka). and mod-ern surface soil. Application of magnetic analyses has provided proxy data sets that represent a time series of climatically regulated pedogenesis/weathering and botanical composition. magetic data have yielded an impression of the variation in climate from Sangamon time to the late Holocene through a reconstruction of the history of pedogenesis/weathering. Sangamon soil formation dominated the reservation durin the Last interglacial as indicated by magnetic parameters. During Gil-man Canyon time loess influx was usually sufficiently slow as to permit pedogenesis which appears to have been at a maximum twice during that time. Warm season grasses were important dur-ing soil formation but diminished in importance during the peri-ods of more rapid loess fall which were cooler and perhaps wet-ter. Peoria loess fall a function of the deterioration of climate during the last Glacial Maximum thinly blanketed the reservation with thickest accumulations occurring to the north-west(Bala Cemetery site)proximal to the source region. Long-term surface stability did not apparently occur within Peoria time but short-term stability may be indicaed by the presence of thin weathering zones(incipient soils) in the Peoria loess. Re-gional landscape stability prevailed during the environmental shift at the Pleistocene/Holocene transition resulting in forma-tion of the well expressed Brady soil. One or more weak soils developed in the Bignell loess as it ac-cumulated. A notable feature of the Bignell loess is the appear-ance of the Altithermal dry period: the loess experienced little weathering and was dominated by warm season grasses until the latter of the Holocene.

• 자원환경지질
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• 제51권6호
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• pp.493-507
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• 2018

제천시 청풍면에 위치한 우석광상은 옥천변성대 동북부 황강리광화대에 속한다. 지질은 조선누층군의 석회암이 넓게 분포하며, 광상 동측에 백악기 무암사화강암이 관입하였다. 광상은 스카른 및 맥상광체가 W-Mo-Fe 및 Cu-Pb-Zn 광화작용을 수반하며, 스카른은 하부갱에서만 발달한다. 광석광물은 스카른광물을 교대 및 절단하며, 자철석-적철석, 휘수연석-회중석-철망간중석, 자류철석-황동석-황철석-섬아연석-방연석 순으로 정출되었고 전반적으로 황화광물이 우세하다. 석류석의 조성은 $Ad_{65.9-97.8}Gr_{0.3-32.0}Pyr_{0.9-3.0}$으로 Fe가 부화된 안드라다이트 계열을 보이며, 휘석은 $Hd_{4.5-49.7}Di_{42.3-93.9}Jo_{0.5-7.9}$로서 투휘석 계열이 우세하여 스카른화 작용이 전체적으로 산화환경에서 진행되었음을 지시한다. 맥상광체에 수반된 섬아연석에 대한 FeS-MnS-CdS 삼각도에서 심부에서 천부로 가면서 FeS는 감소하고 MnS는 증가하는 경향을 보이는데 이는 심부의 W 광화작용과 천부의 Pb-Zn 광화작용과 관련된 것으로 보인다. 황화광물의 황안정동위원소 조성은 5.1-6.8 ‰로 마그마에서 기원된 황이 모암이 영향을 받은 것으로 여겨진다. 우석광상의 W-Mo 스카른 및 Pb-Zn 열수맥상 광화작용은 시공간적으로 심부에서 천부로 가면서 온도 및 산소분압의 감소와 함께 황분압이 증가하면서 진행된 것으로 보인다.