• 제목/요약/키워드: 2-unit

검색결과 14,034건 처리시간 0.037초

IMT-2000 시스템의 AAL2/AAL5 변환장치 설계 및 구현 (Design and Implementation of AAL2/AAL5 Type Conversion unit for IMT-2000 System)

  • 김대연;박형준;장문수
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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    • pp.225-228
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    • 2000
  • In this paper, we present the design of AAL2/AAL5 Type conversion Unit using among BSC, BTS, Core-Network in IMT-2000 system. We first briefly introduce the B-ISDN ATM Adaptation layer specification of Type 2 AAL and Type 5 AAL, and describe conversion flow and each module. And then this paper has designed AAL2/AAL5 Type Conversion Unit and simulated it.

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ITERATIONS OF THE UNIT SINGULAR INNER FUNCITON

  • Kim, Hong-Oh
    • 대한수학회보
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    • 제25권2호
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    • pp.243-246
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    • 1988
  • Let M(z)=exp (-1+z/1-z) be the unit singular inner function. See [1] or [2] for the basic facts about inner functions. We define the iterations of M9z) as (Fig.) Since the composition M$_{2}$(z)=M.M(z) is known (see [5] for example) to be singular inner function it has the "cannonical" representation (Fig.) where .mu. is a finite, positive singular Borel measure on the unit circle T. In section 2, we have explicit cannonical representation of M$_{2}$(z) by determining the singular measure .mu. In section 3 we show that (Fig.) These facts might have been known but could not be found in the literature.iterature.

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Estimating the Home-Purchase Cost of Seoul Citizens

  • 오덕교;제임스 번즈
    • 한국시스템다이내믹스연구
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    • 제12권2호
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    • pp.5-36
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    • 2011
  • Seoul citizens are currently suffering from high housing price. Home prices have risen more rapidly than salaries so owning a housing unit (apartment, condominium, or single-family home) in Seoul is becoming more difficult than ever. Therefore, this research examines the behavior of average Seoul citizen in owning housing unit in Seoul, Korea, particularly in terms of the length of time required to afford a house unit. This research estimates that it will take about 18.75 years in maximum after getting a job (12.75 years after purchasing the housing unit) to own housing unit in Seoul that is currently valued at $300,000 where the growth rate of income is 2.97% and consumption price increases at a rate of 2.95% per annum. Finally in this research, the optimal growth rate of housing price is estimated ranged from 3.5 to 4.0% minimizing the loan payoff period.

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Inhibition of Aminopeptidase N by 2-Hydroxy-3-amino-4-(p-nitrophenyl)butyryl Peptide Derivatives

  • Chung, Myung-Chul;Lee, Choong-Hwan;Lee, Ho-Jae;Chun, Hyo-Kon;Kho, Yung-Hee
    • Applied Biological Chemistry
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    • 제41권8호
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    • pp.608-610
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    • 1998
  • To investigate the inhibitory activity of 2-hydroxy-3-amino-4-phenylbutyrate-harboring aminopeptidase N inhibitors, p-nitro-AHPA-peptide derivatives (1 and 2) and an AHPA-peptide derivative (3) were synthesized by chain elongation from C-terminal end using DCC/HOBt as a coupling reagent. The peptides $1{\sim}3$ exerted strong inhibitory activities against aminopeptidase N with $IC_{50}$ values of 1.8, 7.3 and $24.0\;{\mu}g/ml$, respectively, and cytotoxicity on cancer cell lines in vitro.

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Analysis of Poly(Ethylene-co-Vinyl Acetate) Using Off-line Pyrolysis

  • Choi, Sung-Seen;Kim, Eunha
    • Elastomers and Composites
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    • 제51권1호
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    • pp.63-67
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    • 2016
  • Poly(ethylene-co-vinyl acetate) (EVA) was pyrolyzed to eliminate acetic acid of VA unit using off-line pyrolysis, and the deacetylated EVA was analyzed infrared spectroscopy (IR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). EVA film for deacetylation was prepared by solution casting on aluminum foil and it was pyrolyzed at low temperature of $300^{\circ}C$ in the off-line pyrolysis apparatus. After deacetylation, carbon-carbon double bond (C=C) was formed by 1,2-elimination of the VA unit in the EVA backbone. Most of C=C bonds were trans-1,4-unit and 1,2-unit was also observed. Presence of the 1,2-unit in deacetylated EVA indicates that terminal or branch VA units exist in the raw EVA. Py-GC/MS chromatogram of deacetylated EVA displayed much smaller acetic acid and much more abundant other pyrolysis products than that of raw EVA, which means that the pyrolysis efficiency and separation condition were improved.

고속 Floating Point Unit 설계 (A Design of High Speed Floating Point Unit)

  • 오행수
    • 대한전자공학회논문지TE
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    • 제39권2호
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    • pp.1-5
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    • 2002
  • 부동소수점 시스템은 IEEE754 표준을 따른다. 부동소수점 방식의 가산기를 2의 보수를 사용하지 않고 1의 보수를 사용함으로서 간단히 나타낼 수 있다. 즉 이 시스템은 단지 반전을 함으로서 간단하고 빠른 연산을 수행할 수 있도록 하였다. 새롭게 설계된 가산기의 연산속도 향상을 위해 53bit의 캐리 선택 가산기를 사용하였다. 본 논문에서는 연산속도 향상을 위한 고성능의 효율적인 마이크로프로세서 시스템을 위한 부동소수점 가산 장치를 설계하였다.

과학기술위성 2호 원격검침-명령 유닛 시험모델 설계 및 구현 (Engineering Model Design and Implementation of Telemetry-Command Unit for STSAT-2)

  • 오대수;유창완;남명룡;황동환
    • 한국항공우주학회지
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    • 제33권5호
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    • pp.93-98
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    • 2005
  • 과학기술위성 2호 시스템 내의 각 전자 유닛(Unit)의 상태 정보를 원격검침(Telemetry)하고 원격명령(Telecommand) 내릴 수 있는 원격검침-명령 유닛(Telemetry-Command Unit, TCU)의 시험모델(Engineering Model, EM)의 개발을 완료하고 동작시험 결과를 제시하였다. TCU는 과학기술위성 1호와는 다르게 CPU가 없이 FPGA 만으로 구현하여 소형화, 경량화 및 저 전력화를 실현하고 기술 집약화를 이루었다. 본 논문에서는 TCU의 개념 설계를 소개하고 구현결과를 제시한다.

과학기술위성 2호 Reaction Wheel Assembly Interface Unit Proto Flight Model 개발 (Engineering Model Design and Implementation Proto Flight Model of Reaction Wheel Assembly Interface Unit for STSAT-2)

  • 김세일;강경인;이성호
    • 한국항공우주학회지
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    • 제34권5호
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    • pp.88-92
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    • 2006
  • 과학기술위성 2호 사용되는 구동기인 반작용 휠(Reaction Wheel Assembly, RWA)과 위성 시스템을 연결해주는 인터페이스를 담당하는 Reaction Wheel Assembly Interface Unit(RIU)의 Proto Flight Model의 개발이 완료되고 동작시험을 마쳤다. RIU는 RWA에 공급되는 전원을 켜고 끄는 스위치와 명령을 주고 받는 위성탑재 컴퓨터(OBC)의 통신 회선을 선택하는 멀티플렉서, 그리고 RWA에 연결되는 물리적 통신라인으로 구성된다.

Synthesis and Mesomorphic Properties of Banana-Shaped Mesogens with All-Ester Linking Group

  • Choi, E-Joon;Cui, Xin;Zin, Wang-Choel;Ohk, Chang-Woo;Lim, Tong-Kun;Lee, Ji-Hoon;Kim, Young-Chul;Paek, Sang-Hyon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.197-199
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    • 2007
  • Four banana-shaped compounds have beene synthesized introducing ester linking group into mesogenic unit, varying the central core with 1,6-, 1,7-, 2,3-, and 2,7-naphthylene units, and introducing the dodecyloxy group as the terminal flexible unit. All obtained compounds except one with 1,7-naphthylene unit were reversibly thermotropically liquid crystalline. The compound with 1,7-naphthylene unit could not form the mesophase due to its asymmetrical and sharp substitution angle. The compounds with 1,6- and 2,3-naphthylene units showed an antiferroelectric switchable smectic phase, which has been designated B2 phase. Interestingly, the compound with the 2,3-naphthylene unit showed the two mesophases of B2 and nematic phase.

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