Donnelly, IJ & Watterson, PA 1989, 'Ion-matrix sheath structure around cathodes of complex shape', Journal of Physics D: Applied Physics, vol. 22, no. 1, pp. 90-93.
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Haseyama, M, Nagai, N, Miki, N & Miyanaga, Y 1989, 'Normalized ARMA lattice filter and its terminal conditions', Electronics and Communications in Japan (Part III: Fundamental Electronic Science), vol. 72, no. 2, pp. 1-13.
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AbstractIn this paper it is shown that covariant data of a synthesized signal corresponds to the covariant data of a real signal.This occurs when an ARMA lattice synthesis filter is used and the minimum mean square value of the estimation error is zero.Hence, a new terminal condition of the ARMA lattice filter is derived so that the covariant data of the synthesized signal will always correspond to the covariant data of a real signal.To this end, a design method for the normalized ARMA lattice filter is presented in this paper, and normalized estimation errors are derived. Finally, the starting condition and design for the normalized ARMA lattice filter is given.
Ohkama, H, Miki, N, Nagai, N & Miyanaga, Y 1989, 'A parallel processing architecture for parameter estimation with recursive least squares', Electronics and Communications in Japan (Part III: Fundamental Electronic Science), vol. 72, no. 9, pp. 105-114.
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AbstractThe recursive least‐squares method (RLS) is often employed in the identification of the linear discrete‐time system, in which the parameters are time‐varying. This paper aims at producing the output which is an estimation of the system parameters, and derives a new algorithm which minimizes the RLS criterion with (time‐variable) forgetting factor. A parallel architecture is proposed which executes the algorithm. the derived algorithm is composed of two‐step processes, which are the Agee‐Turner PD factorization update theorem and the forward‐substitution for solving linear triangular systems. the proposed parallel architecture is composed of a large number of processing elements (PE) connected in a regular way. the communication is performed only between adjacent PE, and the architecture can easily be implemented by VLSI. It can be considered as a systolic array composed of PE with a queue (FIFO memory). By introducing PE with a queue, the two‐step processes can be executed in parallel for the first time. It is shown that by employing the proposed parallel architecture composed of (N2 + 5N − 2)/2 PE in the real‐time processing, the estimated parameters for any time can be produced as the output, in a processing time independent of the number of parameters of the estimation, even though the computational complexity is of the order of square of the number of estimated parameters.
Watterson, PA 1989, 'Child-Langmuir sheath structure around wedge-shaped cathodes', Journal of Physics D: Applied Physics, vol. 22, no. 9, pp. 1300-1307.
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The steady state Child-Langmuir sheath around a wedge-shaped cathode immersed in a plasma is calculated numerically. The ions drawn from the plasma may be employed to sputter material from the cathode, or may implant into the cathode, depending upon the magnitude of the applied negative voltage. The ion impact rate onto the cathode reaches 2.2 times higher near a square edge and 3.6 times higher near a knife edge than the rate for planar surfaces of the cathode. However, for a knife edge the rate falls to zero at the edge. All the ions strike the cathode with the same kinetic energy, but the angle of impact is nonperpendicular near the edge, which could reduce the implantation depth and increase sputtering. © 1989 IOP Publishing Ltd.
