The identification, on-line and in near to real-time, of the resonant frequencies, modes and amplitudes of selected key reactor components and the visual monitoring of these phenomena by nuclear power plant operating ...
详细信息
The identification, on-line and in near to real-time, of the resonant frequencies, modes and amplitudes of selected key reactor components and the visual monitoring of these phenomena by nuclear power plant operating staff will serve to further the safety and control philosophy of nuclear systems and lead to design optimisation. The rapid recognition of the onset of unusual or accidental conditions in reactor sub-channels by means of the optimal filtering of noise-like sources will lead to the development of new safety systems. In this paper a computer based nuclear power plant surveillance system utilising pattern recognition techniques is described and the results of preliminary tests and experiments carried out with it are discussed. Computer based algorithms utilising correlation and spectral analysis and linear and non-linear auto-regression techniques are assessed and their optimal utilisation described.
A quasianalytical method is presented for solving nonlinear, open-loop, optimal control problems. The approach combines a simple analytical, straightforward expansion from perturbation methods with powerful numerical ...
详细信息
A quasianalytical method is presented for solving nonlinear, open-loop, optimal control problems. The approach combines a simple analytical, straightforward expansion from perturbation methods with powerful numerical algorithms to solve a series of nonhomogeneous, linear, optimal control problems. In the past, the only recourse for solving such nonlinear problems relied almost exclusively on iterative numerical methods, whereas the asymptotic perturbation approach may produce accurate solutions to nonlinear problems without iteration.
A numerical algorithm has been developed for solving the equations describing chemically reacting supersonic flows. The algorithm employs a two-stage Runge-Kutta method for integrating the equations in time and a Cheb...
详细信息
Sufficient and necessary conditions are derived under which interpolating splines are convex if the data set is in convex position. In order to select one of the interpolants, by means of a well-known objective functi...
详细信息
Sufficient and necessary conditions are derived under which interpolating splines are convex if the data set is in convex position. In order to select one of the interpolants, by means of a well-known objective function a quadratic optimization problem is stated which can be solved effectively by passing to a dual program.
A transient finite difference wave envelope formulation is presented for sound propagation without steady flow. Before the finite difference equations are formulated, the governing wave equation is first transformed t...
详细信息
The optimal projection equations derived previously for reduced-order, continuous-time modeling, estimation, and control are developed for the discrete-time case. The design equations are presented in a concise, unifi...
详细信息
The optimal projection equations derived previously for reduced-order, continuous-time modeling, estimation, and control are developed for the discrete-time case. The design equations are presented in a concise, unified manner to facilitate their accessibility for the development of numerical algorithms for practical applications. As in the continuous-time case, the standard Kalman filter and linear-quadratic-Gaussian results are immediately obtained as special cases of the estimation and control results. (Author)
Various artificial dissipation models that are used with central difference algorithms for the Euler equations are analyzed for their effect on accuracy, stability, and convergence rates. In particular, linear and non...
详细信息
A boundary-layer-type solver is developed for the numerical solution of axisymmetric separated flows. A new, fully implicit coupling scheme for the viscous and inviscid regions is demonstrated. This fully implicit cou...
详细信息
This paper discusses current efforts directed toward extension of numerical modeling of chemical kinetics to hydrocarbon fuel molecules that are much larger than those treated in the past. The techniques needed are de...
详细信息
The exponential function presented here returns a result which differs from ex by less than one unit in the last place, for any representable value of x which is not too close to values for which ex would overflow or ...
详细信息
The exponential function presented here returns a result which differs from ex by less than one unit in the last place, for any representable value of x which is not too close to values for which ex would overflow or underflow. (For values of x which are not within this range, an error condition is raised.)
It is a ?variable precision? function in that it returns a p-digit approximation for a p-digit argument, for any p = 0 (p-digit means p-decimal-digit). The program and analysis are valid for all p = 0, but current implementations place a restriction on p.
The program is presented in a Pascal-like programming language called numerical Turing which has special facilities for scientific computing, including precision control, directed roundings, and built-in functions for getting and setting exponents.
暂无评论