• 제목/요약/키워드: ladder

검색결과 526건 처리시간 0.02초

DVD PRML을 위한 1.8V 6bit IGSPS 초고속 A/D 변환기의 설계 (Design of a 1-8V 6-bit IGSPS CMOS A/D Converter for DVD PRML)

  • 유용상;송민규
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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    • pp.305-308
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    • 2002
  • An 1.8V 6bit IGSPS ADC for high speed data acquisition is discussed in this paper. This ADC is based on a flash ADC architecture because the flash ADC is the only practical architecture at conversion rates of IGSPS and beyond. A straightforward 6bit full flash A/D converter consists of two resistive ladders with 63 laps, 63 comparators and digital blocks. One important source of errors in flash A/D converter is caused by the capacitive feedthrough of the high frequency input signal to the resistive reference-lauder. Consequently. the voltage at each tap of the ladder network can change its nominal DC value. This means large transistors have a large parasitic capacitance. Therefore, a dual resistive ladder with capacitor is employed to fix the DC value. Each resistive ladder generates 32 clean reference voltages which alternates with each other. And a two-stage amplifier is also used to reduce the effect of the capacitive feedthrough by minimizing the size of MOS connected to reference voltage. The proposed ADC is based on 0.18${\mu}{\textrm}{m}$ 1-poly 6-metal n-well CMOS technology, and it consumes 307㎽ at 1.8V power supply.

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삼각분할표에서 구조적 변화점 유무에 관한 검정 (Testing Structural Changes in Triangular Data)

  • 이성임
    • Communications for Statistical Applications and Methods
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    • 제15권4호
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    • pp.551-562
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    • 2008
  • 보험분야에서 지급준비금(loss reserve)을 추정할 때에는 보험사고의 발생년도와 사건발생 이후의 경과년도에 따라 지급된 보험금을 자료로 사용하게 되는데, 이것은 흔히 삼각분할표(run-off triangular table)의 형태로 주어진다. 이러한 삼각분할표 자료에 대하여 지급준비금 추정에 주로 사용되는 방법으로 사다리법(chain-ladder method)이 있는데, 이것은 사고발생년도부터 보험금이 정산되는 시점까지의 경과기간동안 지급된 누적 보험금의 변화율(진전계수)을 추정함으로써 지급준비금을 추정하는 것이다. 이러한 사다리법은 보험사고의 발생년도에 따른 진전계수의 변화가 없다는 가정을 기본전제로 하고 있다. 그러나 여러 가지 사회 환경적 요인으로 인하여 시간이 지남에 따라 지급보험금의 진전패턴이 달라질 수 있고, 본 논문에서는 사건의 변화에 따른 구조적 변화점 유무를 검정할 수 있는 검정법을 제안하고자 한다. 또한 이를 실제 예제에 적용 고찰해 보고자 한다.

교육용 문제 풀기 게임 설계 및 구현 (Design and Implementation of Educational problem solving game)

  • 서정만
    • 한국컴퓨터정보학회논문지
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    • 제15권2호
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    • pp.83-89
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    • 2010
  • 본 논문에서는 게임이 아동들이나 청소년들에게 폭력성을 배제하고 교육적인 내용의 게임을 만들려면 게임의 구성과 설계가 중요하다. 그러므로 본 논문에서는 아동이나 청소년들에게 교육적인 내용의 게임을 설계하여 두뇌 발달을 시키고, 게임의 즐거움을 줄 수 있도록 하였다. 특히 아동들을 위해 화면에서 토끼 같은 캐릭터를 추가하여 게임의 폭력성 보다는 친근한 이미지의 동물들의 캐릭터를 살려 설계하였다. 전체 화면에 대한 객체 설계와 구현된 게임에 대한 화면에 대한 내용도 살펴보았으며, 구현된 게임의 장점을 나열하였고, 향후 발전방향에 대하여 논하였다.

병동 간호사의 임상등급 간호역량 평가도구 개발 (Development of a Nursing Competence Measurement Scale according to Nurse's Clinical Ladder in General Wards)

  • 박미란;김남초
    • 간호행정학회지
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    • 제20권3호
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    • pp.257-271
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    • 2014
  • Purpose: This methodological study was done to develop a Nursing Competency Measurement Scale based on the clinical ladders of nurses working in wards. Methods: Thirty clinical experts and 501 ward nurses evaluated the content validity of the scale. A survey using the Nursing Competency Measurement Scale was conducted with 114 nurses to evaluate reliability and applicability of the instrument. Data were analyzed using SPSS/WIN 21.0. Results: A review of the literature identified 13 components of nursing competencies and 30 core nursing competencies based on each of the 4 grade clinical ladders. Cronbach's ${\alpha}$ coefficient for the total was .92. Cronbach's ${\alpha}$ reliabilities of each clinical ladder grade were .83 for Grade I, .84 for Grade II, .81 for Grade III, and .84 for Grade IV. The Content Validity Index (CVI) of the scale with 120 individual items was 0.976~1.000 for Grade I scale, 0.986~1.000 for Grade II scale, 0.984~1.000 for Grade III scale, and 0.992~1.000 for Grade IV scale. The expert group nurses' average degree of nursing competence measured using the scale was 3.38~3.75 out of 4.0. Conclusion: Through this process, 120 final questions were confirmed to represent items of the Nursing Competency Measurement Scale based on clinical grade.

Twin Target Sputtering System with Ladder Type Magnet Array for Direct Al Cathode Sputtering on Organic Light Emitting Diodes

  • Moon, Jong-Min;Kim, Han-Ki
    • Journal of Information Display
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    • 제8권3호
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    • pp.5-10
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    • 2007
  • Twin target sputtering (TTS) system with a configuration of vertically parallel facing Al targets and a substrate holder perpendicular to the Al target plane has been designed to realize a direct Al cathode sputtering on organic light emitting diodes (OLEDs). The TTS system has a linear twin target gun with ladder type magnet array for effective and uniform confinement of high density plasma. It is shown that OLEDs with Al cathode deposited by the TTS show a relatvely lower leakage current density $({\sim}1{\times}10^{-5}mA/cm^2)$ at reverse bias of -6V, compared to that ($1{\times}10^{-2}{\sim}10^{-3}$ $mA/cm^2$ at -6V) of OLEDs with Al cathodes grown by conventional DC magnetron sputtering. In addition, it was found that Al cathode films prepared by TTS were amorphous structure with nanocrystallines due to low substrate temperature. This demonstrates that there is no plasma damage caused by the bombardment of energetic particles. This indicates that the TTS system with ladder type magnet array could be useful plasma damage free deposition technique for direct Al cathode sputtering on OLEDs or flexible OLEDs.

Seven new species of two genera Scalarispongia and Smenospongia (Demospongiae: Dictyoceratida: Thorectidae) from Korea

  • Kim, Young A;Lee, Kyung Jin;Sim, Chung Ja
    • Journal of Species Research
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    • 제9권2호
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    • pp.147-161
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    • 2020
  • Seven new species of two genera Scalarispongia and Smenospongia (Demospongiae: Dictyoceratida: Thorectidae) are described from Gageo Island and Jeju Island, Korea. Five new species of Scalarispongia are compared to nine reported species of the genus by the skeletal structure. Scalarispongia viridis n. sp. has regular ladder-like skeletal pattern arranged throughout the sponge body and has pseudo-tertiary fibres. Scalarispongia favus n. sp. is characterized by the honeycomb shape of the surface and is similar to Sc. flava in skeletal structure, but differs in sponge shape. Scalarispongia lenis n. sp. is similar to Sc. regularis in skeletal structure but has fibers that are smaller in size. Scalarispongia canus n. sp. has irregular skeletal structure in three dimensions and ladder-like which comes out of the surface and choanosome. Scalarispongia subjiensis n. sp. has pseudo-tertiary fibres and its regular ladder-like skeletal pattern occurs at the choanosome. Two new species of Smenospongia are distinguished from the other 19 reported species of the genus by the skeletal structure. Smenospongia aspera n. sp. is similar to Sm. coreana in sponge shape but new species has rarely secondary web and thin and thick bridged fibres at near surface. Smenospongia mureungensis n. sp. has very simple skeletal structure.

이진 에드워즈 곡선 공개키 암호를 위한 257-비트 점 스칼라 곱셈의 효율적인 하드웨어 구현 (An Efficient Hardware Implementation of 257-bit Point Scalar Multiplication for Binary Edwards Curves Cryptography)

  • 김민주;정영수;신경욱
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2022년도 춘계학술대회
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    • pp.246-248
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    • 2022
  • Bernstein이 제안한 새로운 타원곡선 형태인 이진 에드워즈 곡선 (binary Edwards curves; BEdC)는 예외점이 없어 완전한 덧셈 법칙이 만족한다. 본 논문에서는 투영 좌표계를 적용한 BEdC 상의 점 스칼라 곱셈의 효율적인 하드웨어 구현에 대해 기술한다. 점 스칼라 곱셈을 위해 modified Montgomery ladder 알고리듬을 적용하였으며, 257-비트 이진 덧셈기와 이진 제곱기, 32-비트 이진 곱셈기를 사용하여 하위 이진체 연산을 구현했다. Zynq UltraScale+ MPSoC 디바이스에 구현하여 설계된 BEdC 크립토 코어를 검증하였으며, 점 스칼라 곱셈 연산에 521,535 클록 사이클이 소요된다.

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병원간호사가 지각하는 성장욕구와 조직분위기가 조직사회화에 미치는 영향 (The Effect of Needs for Professional Development and Organizational Climate on Organizational Socialization)

  • 송영신;이미영
    • 임상간호연구
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    • 제16권3호
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    • pp.51-61
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    • 2010
  • Purpose: The purpose of this study was to determine the effect of needs for professional development and organizational climate on organizational socialization of clinical nurses. A cross-sectional analysis were performed to assess the factors affecting organizational socialization. Methods: The data used in this study were obtained from clinical nurses who were employed in a hospital (N=606). Using multiple regression, we tested variables to assess their effects on organizational socialization in this sample. The data were analyzed using descriptive test, t-test, ANOVA, Pearson correlation coefficiency and stepwise multivariate regression. SPSS 17.0 program was utilized for data analysis. Results: The mean scores of organizational socialization, needs for professional development and organizational climate were statistically differed by career ladder, educational level and position. Organizational socialization had significant positive correlations with the needs for professional development (r=.332, p<.01) and organizational climate (r=.523, p<.01). Those variables including career ladder explained 33.4% of organizational socialization. Conclusion: Our findings indicate that organizational socialization of clinical nurses could be enhanced by meeting the needs for professional development and organizational climate. Developing innovative educations for encouraging clinical nurses' carrier development and creating a positive organizational climate are mandated for clinical nurses to have constructive organizational socialization.

GARCH-X(1, 1) model allowing a non-linear function of the variance to follow an AR(1) process

  • Didit B Nugroho;Bernadus AA Wicaksono;Lennox Larwuy
    • Communications for Statistical Applications and Methods
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    • 제30권2호
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    • pp.163-178
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    • 2023
  • GARCH-X(1, 1) model specifies that conditional variance follows an AR(1) process and includes a past exogenous variable. This study proposes a new class from that model by allowing a more general (non-linear) variance function to follow an AR(1) process. The functions applied to the variance equation include exponential, Tukey's ladder, and Yeo-Johnson transformations. In the framework of normal and student-t distributions for return errors, the empirical analysis focuses on two stock indices data in developed countries (FTSE100 and SP500) over the daily period from January 2000 to December 2020. This study uses 10-minute realized volatility as the exogenous component. The parameters of considered models are estimated using the adaptive random walk metropolis method in the Monte Carlo Markov chain algorithm and implemented in the Matlab program. The 95% highest posterior density intervals show that the three transformations are significant for the GARCHX(1, 1) model. In general, based on the Akaike information criterion, the GARCH-X(1, 1) model that has return errors with student-t distribution and variance transformed by Tukey's ladder function provides the best data fit. In forecasting value-at-risk with the 95% confidence level, the Christoffersen's independence test suggest that non-linear models is the most suitable for modeling return data, especially model with the Tukey's ladder transformation.

Structural characterization of ladder-type cadmium(II) citrate complex, (C3H12N2)[{Cd(H2O)(C6H5O7)}2]·6H2O

  • Kim, Chong-Hyeak;Lee, Sueg-Geun
    • 분석과학
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    • 제20권4호
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    • pp.355-360
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    • 2007
  • The title complex, $(C_3H_{12}N_2)[\{Cd(H_2O)(C_6H_5O_7)\}_2]{\cdot}6H_2O$, I, has been prepared and its structure characterized by FT-IR, EDS, elemental analysis, ICP-AES, and X-ray single crystallography. It is triclinic system, $P{\bar{1}}$ space group with a = 10.236(2), b = 11.318(2), c = $13.198(2){\AA}$, ${\alpha}=77.95(1)^{\circ}$, ${\beta}=68.10(1)^{\circ}$, ${\gamma}=78.12(1)^{\circ}$, V = $1373.5(3){\AA}^3$, Z = 2. Complex I has constituted by protonated 1,3-diaminopropane cations, citrate coordinated cadmium(II) anions, and free water molecules. The central cadmium atoms have a capped trigonal prism geometry by seven coordination with six oxygen atoms of three different citrate ligands and one water molecule. Citrate ligands are bridged to three different cadmium atoms. Each cadmium atom is linked by carboxylate and hydroxyl groups of citrate ligand to construct an one-dimensional ladder-type assembly structure. The polymeric crystal structure is stabilized by three-dimensional networks of the intermolecular O-H${\cdots}$O and N-H${\cdots}$O hydrogen-bonding interaction.