MODELING AC ARC RE-IGNITION CONDITIONS ON ICE -COVERED INSULATORS USING ARTIFICIAL NEURAL NETWORKS
The propagation of local arcs are necessary for a flashover to occur on an ice-covered insulator. It was supposed that the local AC arc extended when it satisfied the arc re-ignition conditions. In this paper an attempt has been made to model Va = f ( I , L , x ) for estimating the arc re-ignition conditions as function of leakage current and insulator length using multi-layer feed-forward neural network with back propagation technique. Once trained with experimental results taken from the CIGELE model , the proposed ANN model is then capable of predicting arc maintenance voltage , under any given set of leakage current and insulator length. With the use of the optimized ANN parameters , a prediction accuracy with a %MAE of 2.85% was achieved.
Estimation of time-to-flashover characteristics of contaminated electrolytic surfaces using a neural network
A major field of neural networks (NN) application is function estimation, because the useful properties of NN such as adaptivity and nonlinearity are well suited to function estimation tasks where the equation describing the function is unknown. In this paper the prerequisite training data are obtained from experimental studies performed on a flat plate model for a polluted insulator under power frequency voltage. Detailed studies have been carried to determine the NN parameters which give the best results. Studies have also been carried out to assess the effect of the presence of inadequate data in the training set on modeling accuracy. It is found that, when training is completed, NN is capable of estimating the function t = f(V,L 1 R p ) very efficiently and effectively even when the inadequate data are incorporated in the training set.
Facilitating Spiritual Care in the Rehabilitation Setting
&NA; Nurses, who traditionally have espoused a holistic approach to patient care, are in a unique position to attend to clients’ spiritual needs. The assessment, planning, and provision of spiritual care is particularly important in the rehabilitation setting. Research attention needs to be directed at gaps in the current state of knowledge and practice of spiritual care to meet the needs of rehabilitation clients.