• Title/Summary/Keyword: sine function

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Genetic association tests when a nuisance parameter is not identifiable under no association

  • Kim, Wonkuk;Kim, Yeong-Hwa
    • Communications for Statistical Applications and Methods
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    • v.24 no.6
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    • pp.663-671
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    • 2017
  • Some genetic association tests include an unidentifiable nuisance parameter under the null hypothesis of no association. When the mode of inheritance (MOI) is not specified in a case-control design, the Cochran-Armitage (CA) trend test contains an unidentifiable nuisance parameter. The transmission disequilibrium test (TDT) in a family-based association study that includes the unaffected also contains an unidentifiable nuisance parameter. The hypothesis tests that include an unidentifiable nuisance parameter are typically performed by taking a supremum of the CA tests or TDT over reasonable values of the parameter. The p-values of the supremum test statistics cannot be obtained by a normal or chi-square distribution. A common method is to use a Davies's upper bound of the p-value instead of an exact asymptotic p-value. In this paper, we provide a unified sine-cosine process expression of the CA trend test that does not specify the MOI and the TDT that includes the unaffected. We also present a closed form expression of the exact asymptotic formulas to calculate the p-values of the supremum tests when the score function can be written as a linear form in an unidentifiable parameter. We illustrate how to use the derived formulas using a pharmacogenetics case-control dataset and an attention deficit hyperactivity disorder family-based example.

Hardware Design of Pipelined Special Function Arithmetic Unit for Mobile Graphics Application (모바일 그래픽 응용을 위한 파이프라인 구조 특수 목적 연산회로의 하드웨어 설계)

  • Choi, Byeong-Yoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.8
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    • pp.1891-1898
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    • 2013
  • To efficiently execute 3D graphic APIs, such as OpenGL and Direct3D, special purpose arithmetic unit(SFU) which supports floating-point sine, cosine, reciprocal, inverse square root, base-two exponential, and logarithmic operations is designed. The SFU uses second order minimax approximation method and lookup table method to satisfy both error less than 2 ulp(unit in the last place) and high speed operation. The designed circuit has about 2.3-ns delay time under 65nm CMOS standard cell library and consists of about 23,300 gates. Due to its maximum performance of 400 MFLOPS and high accuracy, it can be efficiently applicable to mobile 3D graphics application.

Research on flow characteristics in supercritical water natural circulation: Influence of heating power distribution

  • Ma, Dongliang;Zhou, Tao;Feng, Xiang;Huang, Yanping
    • Nuclear Engineering and Technology
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    • v.50 no.7
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    • pp.1079-1087
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    • 2018
  • There are many parameters that affect the natural circulation flow, such as height difference, heating power size, pipe diameter, system pressure and inlet temperature and so on. In general analysis the heating power is often regarded as a uniform distribution. The ANSYS-CFX numerical analysis software was used to analyze the flow heat transfer of supercritical water under different heating power distribution conditions. The distribution types of uniform, power increasing, power decreasing and sine function are investigated. Through the analysis, it can be concluded that different power distribution has a great influence on the flow of natural circulation if the total power of heating is constant. It was found that the peak flow of supercritical water natural circulation is maximal when the distribution of heating power is monotonically decreasing, minimal when it is monotonically increasing, and moderate at uniform or the sine type of heating. The simulation results further reveal the supercritical water under different heat transfer conditions on its flow characteristics. It can provide certain theory reference and system design for passive residual heat removal system about supercritical water.

Acoustical Dynamic Response Analysis of a Gas Turbine Combustor Using a Sine-Sweep Forcing Model (사인-스윕 가진 모델을 통한 가스터빈 연소기의 음향 동적 반응 해석)

  • Son, Juchan;Kim, Daesik
    • Journal of the Korean Society of Propulsion Engineers
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    • v.26 no.4
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    • pp.1-9
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    • 2022
  • In the current study, in order to understand the dynamic response characteristics of the system according to the external acoustic forcing, a numerical approach was developed by adding an sign-sweep forcing function to the existing network model. Through this model, the sensitivity of frequency and pressure amplitude changes according to system parameters such as the physical dimensions and boundary conditions of the target combustor was analyzed in a wide frequency range. Analysis results of dynamic response characteristics of the target combustor are shown that the frequency regime with high dynamic pressure response was similar to the instability frequency range measured in the same combustor, and in particular, the response of the system depends greatly on the location of the acoustic forcing source term.

Structural Analysis for Constructing a Balloon Type Extracoporeal Membrane Oxygenator using CFD Analysis (CFD 해석을 이용한 Balloon형 인공심폐기 설계를 위한 구조적 해석)

  • Park, Young-Ran;Shim, Jeong-Yeon;Kim, Gi-Beum;Kim, Shang-Jin;Kang, Hyung-Sub;Kim, Jin-Shang;Kim, Min-Ho;Hong, Chul-Un;Kim, Seong-Jong
    • Korean Chemical Engineering Research
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    • v.49 no.2
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    • pp.238-243
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    • 2011
  • In this study, we attempted a structural analysis in order to design a balloon type extracorporeal membrane oxygenator that can induce blood flow without using blood pumps for the purpose of complementing the weakness in the existing extracorporeal membrane oxygenator. To analyze the flow characteristic of the blood flow within the virtual model of extracorporeal membrane oxygenator, computational fluid dynamics(CFD) modeling method was used. The operating principle of this system is to make the surface of the extracorporeal membrane oxygenator keep contracting and dilating regularly by applying pressure load using a balloon, and the 'ime Function Value'that changes according to the time was applied by calculating a half cycle of sine waveform and a cycle of sine.waveform Under the assumption that the uni-directional blood flow could be induced if the balloon type extracorporeal membrane oxygenator was designed as per the method described above, we conducted a structural analysis accordingly. We measured and analyzed the velocity and pressure of blood flow at both inlet and outlet of the extracorporeal membrane oxygenator through CFD simulation. As a result of the modeling, it was confirmed that there was a flow in accord with the direction of the blood by the contraction/dilation. With CFD simulation, the characteristics of blood flow can be predicted in advance, so it is judged that this will be able to provide the most optimized design in producing an extracorporeal membrane oxygenator.

Modeling Temperature-Dependent Development and Hatch of Overwintered Eggs of Pseudococcus comstodki (Homoptera:Pseudococcidae) (가루깍지벌레(Pseudococcus comstocki (Kuwana))월동알의 온도발육 및 부화시기예찰모형)

  • Jeon, Heung-Yong;Kim, Dong-Soon;Yiem, Myoung-Soon;Lee, Joon-Ho
    • Korean journal of applied entomology
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    • v.35 no.2
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    • pp.119-125
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    • 1996
  • Temperature-dependent development study for overwintered eggs of Pseudococcus comstocki (Kuwana) wasconducted to develop a forecasting model for egg hatch date. Hatch times of overwintered eggs were comparedat five constant temperatures (10, 15, 20, 25, 27$^{\circ}$C) and different collection dates. A nonlinear, four-parameterdevelopmental model with high temperature inhibition accurately described (R2=0.9948) mean developmentalrates of all temperatures. Variation in developmental times was modeled(~~=0.972w9)it h a cumulative Weibullfunction. Least-squares linear regression (rate=O.O06358[Temp.]-0.07566)d escribed development in the linearregion (15-25$^{\circ}$C) of the development curve. The low development threshold temperature was estimated 11.9"Cand 154.14 degree-days were required for complete development. The linear degree-day model (thermal summation)and rate summation model (Wagner et al. 1985) were validated using field phenology data. In degreedaymodels, mean-minus-base method, sine wave method, and rectangle method were used in estimation of dailythermal units. Mean-minus-base method was 18 to 28d late, sine wave method was 11 to 14d late, rectanglemethod was 3 to 5d late, and rate summation model was 2 to 3d late in predicting 50% hatch of overwinteredeggs. hatch of overwintered eggs.

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Evaluation of Comfort Limit on High Speed Railway Bridge Vibration Considering Passenger's Comfort (승차감을 고려한 고속철도 교량 진동사용성 평가)

  • Chin, Won-Jong;Kwark, Jong-Won;Choi, Eun-Suk;Kang, Jae-Yoon;Kim, Sung-Tae;Yoon, Hye-Jin;Kim, Nam-Sik
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.829-835
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    • 2011
  • This paper aims for proposed the deflection limit on vibration serviceability of high-speed railway bridges considering passenger's comfort when a train passes a railway bridge. The vertical acceleration signals of passenger cars obtained from test were compared with them from the bridge-train transfer function by riding KTX. The deflections by KTX of seven high speed railway bridges were assumed as sine and haversine wave. The deflection limit on vibration serviceability of high-speed railway bridges considering passenger's comfort when a train passes a railway bridge duration can be expanded using bridge-train transfer function and bridge comfort limit considering serviceability due to bridge vibration. And it was compared to other allowable deflection limits of railway bridge design specifications.

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FOURIER'S TRANSFORM OF FRACTIONAL ORDER VIA MITTAG-LEFFLER FUNCTION AND MODIFIED RIEMANN-LIOUVILLE DERIVATIVE

  • Jumarie, Guy
    • Journal of applied mathematics & informatics
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    • v.26 no.5_6
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    • pp.1101-1121
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    • 2008
  • One proposes an approach to fractional Fourier's transform, or Fourier's transform of fractional order, which applies to functions which are fractional differentiable but are not necessarily differentiable, in such a manner that they cannot be analyzed by using the so-called Caputo-Djrbashian fractional derivative. Firstly, as a preliminary, one defines fractional sine and cosine functions, therefore one obtains Fourier's series of fractional order. Then one defines the fractional Fourier's transform. The main properties of this fractal transformation are exhibited, the Parseval equation is obtained as well as the fractional Fourier inversion theorem. The prospect of application for this new tool is the spectral density analysis of signals, in signal processing, and the analysis of some partial differential equations of fractional order.

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Direct Adaptive Control for Trajectory Tracking Control of a Pneumatic Cylinder (공기압 실린더의 궤적 추적 제어를 위한 직접 적응제어)

  • Lee, Su-Han;Jang, Chang-Hun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.12
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    • pp.2926-2934
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    • 2000
  • This study presents a direct adaptive controller which is derived by using Lyapunovs direct methods for trajectory tracking control of a pneumatic cylinder. The structure of the controller is very simple and computationally efficient because it does not use either the dynamic model or the parameter values of the pneumatic system. The bounded stability of the system is shown in the presence of the bounded unmodeled dynamics. The bounded size of tracking errors can be made arbitrarily small without giving andy influences on either input or output variables. The trajectory tracking performance and the stability of the control system is verified experimentally. The results of the experiments show that the proposed controller tracks the given trajectories, sine function and cycloidal function trajectories, more accurately than PD controller does, and it stabilizes the system and adaptive variables.

On the Dynamic Response of Laminated Circular Cylindrical Shells under Dynamic Loads (동하중을 받는 복합재료 원통셸의 동적거동 해석)

  • 이영신;이기두
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.11
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    • pp.2684-2693
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    • 1993
  • The free vibration and dynamic response of cross-ply for CFRP and GFRP laminated circular cylindrical shells under dynamic loadings are investigated by using the first-order shear deformation shell theory. The modal analysis technique is used to develop the analytical solutions of simply supported cylindrical shells under dynamic load. The analysis is based on an expansion of the loads, displacements and rotations in a double Fourier series which satisfies the and boundary conditions of simply support. Analytical solution is assumed to be separable into a function of time and a function of position. In this paper, the considered load forces are step pulse, sine pulse, triangular(1, 2, 3) pulse and exponential pulse. The solution for a given loading pulse can be found by involving the convolution integral. The results show that the dynamic response are governed primarily by the natural period of the structure.