• 제목/요약/키워드: R-$\theta$

검색결과 335건 처리시간 0.028초

Some Theorems Connecting the Unified Fractional Integral Operators and the Laplace Transform

  • Soni, R. C.;Singh, Deepika
    • Kyungpook Mathematical Journal
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    • 제45권2호
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    • pp.153-159
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    • 2005
  • In the present paper, we obtain two Theorems connecting the unified fractional integral operators and the Laplace transform. Due to the presence of a general class of polynomials, the multivariable H-function and general functions ${\theta}$ and ${\phi}$ in the kernels of our operators, a large number of (new and known) interesting results involving simpler polynomials (which are special cases of a general class of polynomials) and special functions involving one or more variables (which are particular cases of the multivariable H-function) obtained by several authors and hitherto lying scattered in the literature follow as special cases of our findings. Thus the Theorems obtained by Srivastava et al. [9] follow as simple special cases of our findings.

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Investigation of some Natural Product Extracts as Corrosion Inhibitors for Mild Steel in Acid Mediu

  • Subramania, A.;Sathiya Priya, A.R.;Saravanan, S.;Abdul Nasser, A.J.;Vasudevan, T.
    • Corrosion Science and Technology
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    • 제4권6호
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    • pp.231-235
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    • 2005
  • The inhibitive effect of extracts of tamarind seeds and jackfruit seeds, curry leaves and henna leaves on corrosion of mild steel in 1M HCl solution have been studied by weight loss, potentiodynamic polarization and impedance measurements. Results obtained from the electrochemical techniques were in good agreement with weight loss results. From the weight loss data, the values of surface coverage ($\Theta$) and corrosion rate were calculated. The inhibition efficiency (IE) increased with increasing inhibitor concentration in 1M HCl solution. In all the cases the adsorption of the natural product extracts on the mild steel surface from 1M HCl follows the Langmuir adsorption isotherm relationship. Potentiodynamic polarization studies reveal the fact that all the four natural product extracts act as mixed type inhibitors. The decrease in the inhibition efficiency follows the order: Extracts of jackfruit seed>henna leaves>curry leaves>tamarind seed.

일반 그리드 그래프를 위한 입출력 효율적인 영역 구분자 (I/O Efficient Cycle Region Recognizer for General Grid Graphs)

  • 허준호
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (1)
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    • pp.985-987
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    • 2005
  • 자료의 크기가 방대한 응용 프로그램에서는 메인 메모리와 저장 장치간의 자료 입출력(I/O)이 전체 계산의 주요 병목 요인으로 작용한다. 본 논문은 [2004 한국정보처리학회 추계논문집 제11권 제2호 1139-1142]에서 제안된 그리드(grid) 그래프를 위한 입출력 효율적인 depth-first search (DFS) 알고리즘을 지원하기 위한 입출력 효율적인 영역 구분자를 구하는 알고리즘을 제안 한다. 그 입출력 복잡도 (I/O-Complexity)는 O(Soft(N))이다. 여기서 N=|V|+|E|이고 $sort(N)=\Theta((N/B)log_{M/B}(N/B))$이다.

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DILATIONS FOR POLYNOMIALLY BOUNDED OPERATORS

  • EXNER, GEORGE R.;JO, YOUNG SOO;JUNG, IL BONG
    • 대한수학회지
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    • 제42권5호
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    • pp.893-912
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    • 2005
  • We discuss a certain geometric property $X_{{\theta},{\gamma}}$ of dual algebras generated by a polynomially bounded operator and property ($\mathbb{A}_{N_0,N_0}$; these are central to the study of $N_{0}\timesN_{0}$-systems of simultaneous equations of weak$^{*}$-continuous linear functionals on a dual algebra. In particular, we prove that if T $\in$ $\mathbb{A}$$^{M}$ satisfies a certain sequential property, then T $\in$ $\mathbb{A}^{M}_{N_0}(H) if and only if the algebra $A_{T}$ has property $X_{0, 1/M}$, which is an improvement of Li-Pearcy theorem in [8].

원관 주위의 2차원 전도열전달과 국소 대류열전달 (Two-dimensional Heat Conduction and Convective Heat Transfer a Circular Tube in Cross Flow)

  • 이억수
    • Journal of Advanced Marine Engineering and Technology
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    • 제29권1호
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    • pp.25-33
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    • 2005
  • When a circular tube with uniform heat generation within the wall was placed in a cross flow, heat flows by conduction in the circumferential direction due to the asymmetric nature of the fluid flow around the perimeter of the circular tube The circumferential heat flow affects the wall temperature distribution to such an extent that. in some cases, significantly different results may be obtained for geometrically similar surfaces. In the present investigation, the effect of circumferential wall heat conduction is investigated for forced convection around circular tube in cross flow of air and water Two-dimensional temperature distribution $T_w(r,{\theta})$ is calculated through the numerical analysis. The difference between one-dimensional and two-dimensional solutions is demonstrated on the graph of local heat transfer coefficients. It is observed that the effect of working fluid is very remarkable.

머시닝센터의 원운동정도 측정시스템의 구성 (Organizartion of Measurin System of Circular Motion Accuracy of Machining Center)

  • 김영석;낭궁석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1993년도 추계학술대회 논문집
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    • pp.305-311
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    • 1993
  • In recent years, it has been variously developed for testing the accuracy of circular motion of NC machine tools, for example Telescoping Ball Bar Method by Bryan,Circular Test Method by Knapp and r $_{- \theta}$ Mathod by Tsutsumi etc., but it is not yet settled in the code of measuring methods of motion errors of NC machine tools, because of errors of measuring units and sensors, and also especially the difficulties of centering of measuring units. In this paper, in use of magnetic type linear scale with resolution of 0.5 .mu. m and tick pulses come out from computer, it has become possible for detecting of linear displacement of radial errors and measuring of revolution angle of circular motion of NC machine tools.

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System Size and Service Size Distributions of a Batch Service Queue

  • Lee, Soon-Seok;Lee, Ho-Woo;Yoon, Seung-Hyun;Nadrajan, R.
    • 한국경영과학회지
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    • 제18권3호
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    • pp.179-186
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    • 1993
  • We derive the arbitrary time point system size distribution of M/ $G^{B}$1 queue in which late arrivals are not allowed to join the on-going service. The distribution is given by P(z) = $P_{4}$(z) $S^{*}$ (.lambda.-.lambda.z) where $P_{4}$ (z) is the probability generating function of the queue size and $S^{*}$(.theta.) is the Laplace-Stieltjes transform of the service time distribution function. We also derive the distribution of the service siez at arbitrary point of time. time.

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선형변환 분할기법을 이용한 고속분할 조류 계산 앨고리즘에 관한 연구 (A study on Fast Decoupled Load Flow Algorithm using the decoupling technique via linear transformation)

  • 송길영;최상규;황문백
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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    • pp.115-117
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    • 1988
  • The algorithm presented here achieves mathematically better decoupling of the MW-$\theta$ and MVARE Calculations by applying linear transformations to load flow equation on paired initial power. The linear transformations to decouple Jacobian matrix prove to be highly profitable considering both Convergence characteristics and computation time per iteration to those required by the FDLF, because the decoupling does not rely on the assumption that the transmission lines have high X/R ratios.

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지중송전케이블 접속부에서의 열전달에 관한 연구 (A Study on Heat Transfer of an Underground Power Transmission Cable-Joint)

  • 박만흥;김재근;이재헌
    • 설비공학논문집
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    • 제5권4호
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    • pp.265-277
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    • 1993
  • Recently, underground transmission system is growing continuously according to the electric power demand increase in the downtown area. Even if domestic cable makers are manufacturing 154kV oil filled cable and joint, the design technology of cable-joint has not been fully self-reliance. This study is aimed at the detail heat transfer analysis of 154kV cable-joint. So, that is cut into the five sections in order to analyze a conjugate natural convection in two dimensional $r-{\theta}$ coordinate. The streamline and temperature distributions are obtained for each sections. Also the changes of those are analyzed with respect to the variation of transmission currents and cable-joint surface heat transfer coefficients. The same analyses are also shown in view point of the maximum temperature of conductor and local equivalent conductivity.

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철극형 동기발전기의 1상중성점간단락 (Line-to-neutral short circuit)

  • 이면영
    • 전기의세계
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    • 제13권1호
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    • pp.1-5
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    • 1964
  • 철심형 동기발전기를 무부하로 운전하는 중 1상중성점간에 단락사고가 돌발한 경우에 그 단락상의 전기자전류와 계자전류를 표시하는 식을 구하여 본다. 식(12)의 단락전류 $i_{L-N}$을 단수형으로 전개해서 기수배조파와 우수배조파로 분리해서 검토를 하고 계자전류 I는 곧 I=E+2/3( $x_{d}$-x'$_{x}$) $i_{L-N}$cos .theta.의 관계식에서 일단 단락전류 $i_{L-N}$가 구해졌으므로 단지 대입하므로써 간단히 얻어진다. 식(12)와 (17)을 도시하는데 필요한 동기기정수를 $x_{d}$=0.78, $x_{q}$ =0.48, x'$_{d}$=0.21, r=0.03, $T_{0}$=163 및 E=1의 perunit치로 가정한다.it치로 가정한다.

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