• 제목/요약/키워드: Differential Concept

검색결과 228건 처리시간 0.022초

신개념 스위칭 소자를 위한 모트-절연체 금속 전이 기술 (Mott-Insulator Metal Switching Technology for New Concept Devices)

  • 김현탁;노태문
    • 전자통신동향분석
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    • 제36권3호
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    • pp.34-40
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    • 2021
  • For developing a switching device of a new concept that cannot be implemented with a semiconductor device, we introduce the Mott insulator-metal transition (IMT) phenomenon occurring out of the semiconductor regime, such as the temperature-driven IMT, the electric-field or voltage-driven IMT, the negative differential resistance (NDR)-IMT switching generated at constant current, and the NDR-based IMT-oscillation. Moreover, the possibilities of new concept IMT switching devices are briefly explained.

$E_N^{n_N}$상의 비선형 퍼지 미분방정식에 대한 대역해의 존재성 (The existence of a global solution for the nonlinear fuzzy differential equations in $E_N^{n_N}$)

  • Kwun, Young-Chul;Kang, Jum-Ran;Park, Dong-Gun;Kim, Seon-Yu
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 춘계 학술대회 학술발표 논문집
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    • pp.1-4
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    • 2003
  • This paper we study the existence of a global solution for the nonlinear fuzzy differential equations in E$_{N}$$^{n}$ by using the concept of fuzzy number of dimension n whose values are normal, convex, upper semicontinuous and compactly supported surface in R$^{n}$ . .

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미분변환법에 의한 탄성 지반상의 열림 균열을 가진 Euler-Bernoulli보의 진동 해석

  • 황기섭;윤종학;유영찬;신영재
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 추계학술대회논문집
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    • pp.690-695
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    • 2003
  • The main purpose of this paper is to apply differential transformation method to vibration analysis of Euler-Bernoulli beam with open cracks on elastic foundation. The governing equation of motion of beam with open cracks on elastic foundation is derived. The concept of differential transformation is briefly introduced. The cracks are modeled by massless substitute spring. The effects of the crack location, size and the foundation constants, on the natural frequencies of the beam, are investigated.

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EXISTENCE OF FUNCTIONAL DIFFERENTIAL EQUATIONS WITH STEPANOV FORCING TERMS.

  • Lee, Hyun Mork
    • 충청수학회지
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    • 제33권3호
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    • pp.351-363
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    • 2020
  • We introduce a new concept of Stepanov weighted pseudo almost periodic functions of class r which have been established by recently in [20]. Furthermore, we study the uniqueness and existence of Stepanov weighted pseudo almost periodic mild solutions of partial neutral functional differential equations having the Stepanov pseudo almost periodic forcing terms on finite delay.

Single-ended Differential RF Circuit Topologies Utilizing Complementary MOS Devices

  • Kim, Bonkee;Ilku Nam;Lee, Kwyro
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제2권1호
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    • pp.7-18
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    • 2002
  • Single-ended differential RF circuit topologies fully utilizing complementary characteristics of both NMOS and PMOS are proposed, which have inherent advantage of both single-ended and differential circuits. Using this concept, we propose a CCPP (Complementary CMOS parallel push-pull) amplifier which has single-ended input/output with differential amplifying characteristics, leading to more than 30 dB improvement on $IIP_2$. In addition, complementary resistive mixer is also proposed, which provides not only differential IF outputs from single-ended RF input, but much better linearity as well as isolation characteristics. Experimental results using $0.35{\;}\mu\textrm{m}$ CMOS process show that, compared with conventional NMOS resistive mixer, the proposed mixer shows 15 dB better LO-to-IF isolation, 4.6 dB better $IIP_2$, and 4.5 dB better $IIP_3$performances.

Differential Code-Filtering Correlation Method for Adaptive Beamforming

  • Hefnawi Mostafa;Denidni Tayeb A.
    • Journal of Communications and Networks
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    • 제7권3호
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    • pp.258-262
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    • 2005
  • An adaptive beamforming system based on code filtering and differential correlation approaches is proposed. The differential correlation method was originally proposed for time delay estimation of direct sequence code division multiple access (DS-CDMA) systems under near-far ratio conditions and the code filtering correlation algorithm, on the other hand, was proposed for array response estimation in DS-CDMA systems under perfect power control. In this paper, by combining differential correlation concept with the code filtering beamforming technology, an accurate estimate of the beam forming weights and an enhanced performance of DS-CDMA systems under sever near-far ratio conditions is achieved. The system performance in terms of beam pattern and bit-error-rate (HER) shows that the proposed adaptive beamformer outperforms the conventional code filtering correlation technique.

Harmonic differential quadrature (HDQ) for axisymmetric bending analysis of thin isotropic circular plates

  • Civalek, Omer;Ulker, Mehmet
    • Structural Engineering and Mechanics
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    • 제17권1호
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    • pp.1-14
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    • 2004
  • Numerical solution to linear bending analysis of circular plates is obtained by the method of harmonic differential quadrature (HDQ). In the method of differential quadrature (DQ), partial space derivatives of a function appearing in a differential equation are approximated by means of a polynomial expressed as the weighted linear sum of the function values at a preselected grid of discrete points. The method of HDQ that was used in the paper proposes a very simple algebraic formula to determine the weighting coefficients required by differential quadrature approximation without restricting the choice of mesh grids. Applying this concept to the governing differential equation of circular plate gives a set of linear simultaneous equations. Bending moments, stresses values in radial and tangential directions and vertical deflections are found for two different types of load. In the present study, the axisymmetric bending behavior is considered. Both the clamped and the simply supported edges are considered as boundary conditions. The obtained results are compared with existing solutions available from analytical and other numerical results such as finite elements and finite differences methods. A comparison between the HDQ results and the finite difference solutions for one example plate problem is also made. The method presented gives accurate results and is computationally efficient.

양대동맥 좌심실기시증치험 1례 (Double Outlet Left Ventricle - One Case Report -)

  • 성후식
    • Journal of Chest Surgery
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    • 제20권4호
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    • pp.798-802
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    • 1987
  • Origin of both great vessels from morphological left ventricle [DOLV] is a rare cardiac anomaly which embryologic possibility has been explained by differential conal development concept and differential canal absorption concept. Recently we had surgical experience of DOLV in 4 month-age infant weighing 5.7Kg. The chief complaints on admission were cyanosis and anoxic spell during severe crying, and right heart catheterization and right ventriculogram were performed but incorrect diagnosis was made. The operative procedures were ligation of patent ductus arteriosus, patch closure of subaortic VSD aligning aorta and pulmonary artery with left ventricle, suture closure of proximal pulmonary artery and valve and the use of extracardiac valved conduit [Carpentier-Edward l4mm] from right ventricle to distal pulmonary artery. Postoperative course was uneventful and discharged in the good condition.

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DLCT를 활용한 향상된 차분선형 분석 (Improved Differential-Linear Cryptanalysis Using DLCT)

  • 김현우;김성겸;홍득조;성재철;홍석희
    • 정보보호학회논문지
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    • 제28권6호
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    • pp.1379-1392
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    • 2018
  • 차분선형 분석의 복잡도는 라운드 독립성, 선형 근사식 독립성, 차분 경로를 만족하지 못하는 경로에 대한 균일성 가정 아래 계산되는 차분선형 특성의 확률에 큰 영향을 받는다. 따라서 차분선형 특성의 정확한 확률을 계산하는 것은 공격의 유효성과 관련된 매우 중요한 문제이다. 본 논문은 차분선형 분석을 위한 새로운 개념 DLCT(Differential-Linear Connectivity Table)를 제안한다. 그리고 DLCT를 적용하여 선형 근사식 독립성 가정을 완화할 수 있는 차분선형 특성의 향상된 확률 계산 방법을 제안하며, DES와 SERPENT에 적용하여 기존 분석결과를 재분석한다. DES의 7-라운드 차분선형 특성의 확률은 $1/2+2^{-5.81}$, SERPENT의 9-라운드 차분선형 특성의 확률은 $1/2+2^{-57.9}$로 다시 계산되었고 공격에 필요한 데이터 복잡도는 각각 $2^{0.2}$, $2^{2.2}$배 감소한다.