• 제목/요약/키워드: various function

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Exploring Cross-function Domain Interaction Map

  • Li, Xiao-Li;Tan, Soon-Heng;Ng, See-Kiong
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2005.09a
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    • pp.431-436
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    • 2005
  • Living cells are sustained not by individual activities but rather by coordinated summative efforts of different biological functional modules. While recent research works have focused largely on finding individual functional modules, this paper attempts to explore the connections or relationships between different cellular functions through cross-function domain interaction maps. Exploring such a domain interaction map can help understand the underlying inter-function communication mechanisms. To construct a cross-function domain interaction map from existing genome-wide protein-protein interaction datasets, we propose a two-step procedure. First, we infer conserved domain-domain interactions from genome-wide protein-protein interactions of yeast, worm and fly. We then build a cross-function domain interaction map that shows the connections of different functions through various conserved domain interactions. The domain interaction maps reveal that conserved domain-domain interactions can be found in most detected cross-functional relationships and a f9w domains play pivotal roles in these relationships. Another important discovery in the paper is that conserved domains correspond to highly connected protein hubs that connect different functional modules together.

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AN EXTENSION OF THE EXTENDED HURWITZ-LERCH ZETA FUNCTIONS OF TWO VARIABLES

  • Choi, Junesang;Parmar, Rakesh K.;Saxena, Ram K.
    • Bulletin of the Korean Mathematical Society
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    • v.54 no.6
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    • pp.1951-1967
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    • 2017
  • We aim to introduce a further extension of a family of the extended Hurwitz-Lerch Zeta functions of two variables. We then systematically investigate several interesting properties of the extended function such as its integral representations which provide extensions of various earlier corresponding results of two and one variables, its summation formula, its Mellin-Barnes type contour integral representations, its computational representation and fractional derivative formulas. A multi-parameter extension of the extended Hurwitz-Lerch Zeta function of two variables is also introduced. Relevant connections of certain special cases of the main results presented here with some known identities are pointed out.

Bayesian Semi-Parametric Regression for Quantile Residual Lifetime

  • Park, Taeyoung;Bae, Wonho
    • Communications for Statistical Applications and Methods
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    • v.21 no.4
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    • pp.285-296
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    • 2014
  • The quantile residual life function has been effectively used to interpret results from the analysis of the proportional hazards model for censored survival data; however, the quantile residual life function is not always estimable with currently available semi-parametric regression methods in the presence of heavy censoring. A parametric regression approach may circumvent the difficulty of heavy censoring, but parametric assumptions on a baseline hazard function can cause a potential bias. This article proposes a Bayesian semi-parametric regression approach for inference on an unknown baseline hazard function while adjusting for available covariates. We consider a model-based approach but the proposed method does not suffer from strong parametric assumptions, enjoying a closed-form specification of the parametric regression approach without sacrificing the flexibility of the semi-parametric regression approach. The proposed method is applied to simulated data and heavily censored survival data to estimate various quantile residual lifetimes and adjust for important prognostic factors.

ATP and GTP Hydrolytic Function of N-terminally Deleted Annexin I

  • Hyun, Young-Lan;Park, Young-Min;Na, Doe-Sun
    • BMB Reports
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    • v.33 no.4
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    • pp.289-293
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    • 2000
  • Annexin I is a 37 kDa member of the annexin family of calcium-dependent phospholipid binding proteins. Annexin I plays regulatory roles in various cellular processes including cell proliferation and differentiation. Recently we found that annexin I is a heat shock protein (HSP) and displays a chaperone-like function. In this paper we investigated the function of annexin I as an ATPase using 1 to 32 amino acids deleted annexin I (${\Delta}-annexin$ I). ${\Delta}-Annexin$ I hydrolyzed ATP as determined by thin layer chromatography. The ability of ATP hydrolysis was inhibited by ADP, GTP and GDP, but not by the AMP, GMP and cAMP. In view of the ATP hydrolyzing function of HSP, the results support the function of annexin I as a HSP.

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THE INCOMPLETE LAURICELLA AND FIRST APPELL FUNCTIONS AND ASSOCIATED PROPERTIES

  • Choi, Junesang;Parmar, Rakesh K.;Chopra, Purnima
    • Honam Mathematical Journal
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    • v.36 no.3
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    • pp.531-542
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    • 2014
  • Recently, Srivastava et al. [18] introduced the incomplete Pochhammer symbol and studied some fundamental properties and characteristics of a family of potentially useful incomplete hypergeometric functions. Here we introduce the incomplete Lauricella function ${\gamma}_D^{(n)}$ and ${\Gamma}_D^{(n)}$ of n variables, and investigate certain properties of the incomplete Lauricella functions, for example, their various integral representations, differential formula and recurrence relation, in a rather systematic manner. Some interesting special cases of our main results are also considered.

A Data Fitting Technique for Rational Function Models Using the LM Optimization Algorithm (LM 최적화 알고리즘을 이용한 유리함수 모델의 데이터 피팅)

  • Park, Jae-Han;Bae, Ji-Hun;Baeg, Moon-Hong
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.8
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    • pp.768-776
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    • 2011
  • This paper considers a data fitting problem for rational function models using the LM (Levenberg-Marquardt) optimization method. Rational function models have various merits on representing a wide range of shapes and modeling complicated structures by polynomials of low degrees in both the numerator and denominator. However, rational functions are nonlinear in the parameter vector, thereby requiring nonlinear optimization methods to solve the fitting problem. In this paper, we propose a data fitting method for rational function models based on the LM algorithm which is renowned as an effective nonlinear optimization technique. Simulations show that the fitting results are robust against the measurement noises and uncertainties. The effectiveness of the proposed method is further demonstrated by the real application to a 3D depth camera calibration problem.

Robust Stable Conditions Based on the Quadratic Form Lyapunov Function (2차 형식 Lyapunov 함수에 기초한 강인한 안정조건)

  • Lee, Dong-Cheol;Bae, Jong-Il;Jo, Bong-Kwan;Bae, Chul-Min
    • Proceedings of the KIEE Conference
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    • 2004.07d
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    • pp.2212-2214
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    • 2004
  • Robust stable analysis with the system bounded parameteric variation is very important among the various control theory. This study is to investigate the robust stable conditions using the quadratic form Lyapunov function in which the coefficient matrix is affined linear system. The quadratic stability using the quadratic form Lyapunov function is not investigated yet. The Lyapunov unction is robust stable not to be dependent by the variable parameters, which means that the Lyapunov function is conservative. We suggest the robust stable conditions in the Lyapunov function in which the variable parameters are dependent in order to reduce the conservativeness of quadratic stability.

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전달함수를 이용한 유정압테이블 운동정밀도 해석법의 제안 및 이론적 검증

  • 오윤진;박천홍;이후상;홍준희
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2001.04a
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    • pp.9-14
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    • 2001
  • A new model utilizing a transfer function is introduced in the present paper for analizing motion errors of hydrostatic tables. Relationship between film reaction force in a single hydrostatic pad and form error of a guide rail is derived at various spacial frequencies by finite element analysis, and it is expressed as a transfer function. This transfer function clarifies so called averaging effect of the oil film quantitively. For example, it is found that the amplitide of the film reaction force is reduced as the spacial frequency increases or relative width of the pocket is reduced. Motion errors of a multiple pad table is estimated from transfer function, geometric relationship between each pads and form errors of a guide rail, which is named as Transfer Function Method. Calculated motion errors by TFM show good agreement with motion errors calculated by Multi Pad Method, which is considered entire table as an analysis object. From the results, it is confirmed that the proposed TFM is very effective to analyze the motion errors of hydrostatic tables.

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Application of Weight Function Method to the Mixed-Mode Stress Intensity Factor Analysis of Cracks in Bolted Joints (볼트 체결부 균열의 혼합모드 응력확대계수 해석에 대한 가중함수법의 적용)

  • Heo, Sung-Pil;Yang, Won-Ho;Chung, Ki-Hyun;Cho, Myoung-Rae;Hyun, Cheol-Seung
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.212-217
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    • 2000
  • The reliable determination of the stress intensity factors for cracks in bolted Joints is needed to evaluate the safety and fatigue life of them widely used in mechanical components. The weight function method is an efficient technique to calculate the stress intensity factors for various loading conditions using the stresses of an uncracked model. In this paper the mixed-mode stress intensity factors for cracks in bolted joints are obtained by weight function method, in which the coefficients of weight function are determined by finite element analyses far reference loadings. The effects of the magnitude of clearance and factional coefficient on the stress intensity factors are investigated.

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Measurement and Analysis of Back-EMF and Thrust of a Linear Brushless DC Motor (선형 브러시리스 DC 모터의 역기전력과 추력 측정 및 분석)

  • 이춘호;김용일;현동석
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.8
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    • pp.183-192
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    • 1998
  • In this paper, we measure the back-EMF and the thrust of a linear brushless DC motor along the relative position between coils and magnets in various speed environments in order to obtain the back-EMF and the thrust as a function of a motor position. The measured back-EMF function and thrust function of the position differ from the analytical ones within 5%. The measured back-EMF and thrust function can, then, be employed in controlling the thrust ripple of the linear motor. Furthermore, to minimize the torque ripple of the linear motor, we suggest the design method to shape the back-EMF and thrust function of the linear motor.

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