• 제목/요약/키워드: infinite type

검색결과 208건 처리시간 0.023초

NEW CONGRUENCES FOR ℓ-REGULAR OVERPARTITIONS

  • Jindal, Ankita;Meher, Nabin K.
    • 대한수학회지
    • /
    • 제59권5호
    • /
    • pp.945-962
    • /
    • 2022
  • For a positive integer ℓ, $\bar{A}_{\ell}(n)$ denotes the number of over-partitions of n into parts not divisible by ℓ. In this article, we find certain Ramanujan-type congruences for $\bar{A}_{r{\ell}}(n)$, when r ∈ {8, 9} and we deduce infinite families of congruences for them. Furthermore, we also obtain Ramanujan-type congruences for $\bar{A}_{13}(n)$ by using an algorithm developed by Radu and Sellers [15].

유한요소법과 하이브리드형 무한요소법을 이용한 초음파 집속변환자의 음장 해석 (Acoustic Field Analysis of Ultrasonic Focusing Transducer by Using Finite Element. Method and Hybrid Type Infinite Element Method)

  • 박순종;윤종락;하강열;김천덕
    • 한국음향학회지
    • /
    • 제14권5호
    • /
    • pp.36-43
    • /
    • 1995
  • 본 논문에서는 유한요소법과 하이브리드형 무한요소법을 사용하여 전기계$\cdot$기계계$\cdot$음향계로 결합된 초음파 집속변환자의 집속특성과 시간 응답을 구하였다. 초음파 집속변환자의 촛점거리, 분해능 특성들을 구하였고, 댐퍼가 부가된 경우 방사면상의 변위분포가 안정되어 분해능이 개선된다는 것을 집속특성과 시간 응답으로부터 해석하였다. 해석의 결과는 초음파 집속변환자의 설계나 성능해석에 응용될 수 있을 것이다.

  • PDF

구형 배플상의 피스톤 음원에 대한 방사임피던스 계산 (Calculation of Radiation Impedance for Piston Sources on a Spherical Baffle)

  • 박순종;김무준;김천덕
    • 한국음향학회지
    • /
    • 제22권1호
    • /
    • pp.54-60
    • /
    • 2003
  • 구형 배플상의 피스톤 음원에 대하여 방사임피던스 특성을 2차원 축대칭 유한요소법과 하이브리드형 무한요소법을 사용하여 수치 해석하였다. 강체 배플에 있어서 피스톤 음원의 방사면 크기에 따른 자기방사임피던스 변화와 피스톤 음원간의 상호방사임피던스 변화를 계산한 결과는 알려진 해석해와 잘 일치하였다. 또한 비강체 배플의 적용에 따른 자기방사임피던스 및 상호방사임피던스의 변화를 규명함으로서 음향변환기의 설계 및 방사특성 해석에 응용되어질 것으로 기대된다.

유한요소법과 하이브리드형 무한요소법의 결합에 의한 축대칭 변환기의 음향 특성해석(II) ;광대역 배열 변환기의 설계 및 그 음향특성 (Acoustic Characteristics Analysis of the Axi-symmetric Transducer by the combined Finite Element Method and Hybrid Type Infinite Element Method, Part II : Wideband Array Transducer Design and its Acoustic Characteristics)

  • 김천덕;김원호;김대환;윤종락
    • 한국음향학회지
    • /
    • 제13권2호
    • /
    • pp.68-75
    • /
    • 1994
  • 본 논문은 두 편으로 연결된 논문의 둘째편으로 광대역 배열변환기의 설계방법과 설계된 변환기의 음향특성을 제시한다. 아울러 유한요소법과 하이브리드형 무한요소법의 결합기법에 의한 설계된 변환기의 음향특성 결과가 등가회로 해석 기법에 의한 결과보다 양호함을 확인하였다. 따라서 제시된 변환기 해석기법이 광대역 배열 변환기의 설계 및 음향특성 해석에 응용될 수 있을 것으로 판단된다.

  • PDF

일반화 감마분포에 근거한 소프트웨어 최적방출시기에 관한 비교 연구 (A Study on Optimal Release Time for Software Systems based on Generalized Gamma Distribution)

  • 김재욱;김희철
    • 디지털산업정보학회논문지
    • /
    • 제6권1호
    • /
    • pp.55-67
    • /
    • 2010
  • Decision problem called an optimal release policies, after testing a software system in development phase and transfer it to the user, is studied. The applied model of release time exploited infinite non-homogeneous Poisson process. This infinite non-homogeneous Poisson process is a model which reflects the possibility of introducing new faults when correcting or modifying the software. The failure life-cycle distribution used generalized gamma type distribution which has the efficient various property because of various shape and scale parameter. Thus, software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement becomes an optimal release policies. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, estimated software optimal release time.

Minimum Variance FIR Smoother for Model-based Signals

  • Kwon, Bo-Kyu;Kwon, Wook-Hyun;Han, Soo-Hee
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2005년도 ICCAS
    • /
    • pp.2516-2520
    • /
    • 2005
  • In this paper, finite impulse response (FIR) smoothers are proposed for discrete-time systems. The proposed FIR smoother is designed under the constraints of linearity, unbiasedness, FIR structure, and independence of the initial state information. It is also obtained by directly minimizing the performance criterion with unbiased constraints. The approach to the MVF smoother proposed in this paper is logical and systematic, while existing results have heuristic assumption, such as infinite covariance of the initial state. Additionally, the proposed MVF smoother is based on the general system model that may have the singular system matrix and has both system and measurement noises. Thorough simulation studies, it is shown that the proposed MVF smoother is more robust against modeling uncertainties numerical errors than fixed-lag Kalman smoother which is infinite impulse response (IIR) type estimator.

  • PDF

Study on the Electromagnetic Coupling of Slots with Finite Thickness in the Parallel-Plate Structure

  • Sungtek Kahng;Park, Jaehoon
    • 한국전자파학회:학술대회논문집
    • /
    • 한국전자파학회 2001년도 종합학술발표회 논문집 Vol.11 No.1
    • /
    • pp.111-114
    • /
    • 2001
  • In this paper, the electromagnetic coupling problems are tackled on slots with nonzero thickness. The analysis is carried out by combination of the thin-wire concept and the Method of Moment(MoM) for the sake of improving computation efficiency. Under the conditions to be presented, slots can be replaced with wires that have effective radii. Also, the infinite summation-type Green's functions are calculated for the parallel-pale structure. A slot in an infinite ground is analyzed and its results are compared with the measurement in a literature. Furthermore, it is examined how the slots couple in parallel plates.

  • PDF

SELF-SIMILAR SOLUTIONS FOR THE 2-D BURGERS SYSTEM IN INFINITE SUBSONIC CHANNELS

  • Song, Kyung-Woo
    • 대한수학회보
    • /
    • 제47권1호
    • /
    • pp.29-37
    • /
    • 2010
  • We establish the existence of weak solutions in an infinite subsonic channel in the self-similar plane to the two-dimensional Burgers system. We consider a boundary value problem in a fixed domain such that a part of the domain is degenerate, and the system becomes a second order elliptic equation in the channel. The problem is motivated by the study of the weak shock reflection problem and 2-D Riemann problems. The two-dimensional Burgers system is obtained through an asymptotic reduction of the 2-D full Euler equations to study weak shock reflection by a ramp.

초소형 비행체 주위의 저 레이놀즈수 영역에 대한 수치 해석 및 실험적 연구 (Numerical Analysis and Experimental Study for Low Reynolds number region around Micro Air Vehicle)

  • 김영훈;김우례;김종암;노오현
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2002년도 춘계 학술대회논문집
    • /
    • pp.53-58
    • /
    • 2002
  • A three-dimensional incompressible Navier-Stokes solver is developed for the flow analysis around Micro Air Vehicle(MAV) designed by MACDL(Micro Aerodynamic Control and Design Lab), Seoul National Univ., Validations of this solver are presented for two cases, first flow over the circular cylinder with infinite length, second flow over infinite wing with wing section, E387 airfoil. Simultaneously, Wind Tunnel test is performed with Flatform Wire type sir-component balance and model designed by MACDL. The numerical results are also examined through comparison with experimental data.

  • PDF