The present paper mainly deals with the prediction of blast-induced ground vibration level at Tourah Mine in Egypt. The safe charge of explosive and peak particle velocity (PPV) were recorded for 79 blast events (79 blast data sets) at various distances. These datasets were used and analyzed by the widely used vibration predictors. From the six predictors, vibration levels were calculated and compared with new monitored 15 blast data sets. Again, the same data sets were used to validate and test the three-layer feed-forward back-propagation neural network to predict the PPV. Different propagations equations were derived by using the shapes of the selected predictors formulae. It is found that among all the predictors, ANN provides very near prediction with high degree of correlation.

The prediction of ground vibration remains a challenging problem for mines, quarries and construction sites. Many numbers of predictor equations have been proposed by various researchers all over the world to predict ground vibration prior to blasting. Till now, it is difficult to recommend any one general predictor for all blasting conditions because ground vibration is influenced by a number of parameters. These parameters are either controllable or non-controllable like blast geometry, explosive types, rock strength properties, geological conditions, and etc. In the this paper, an attempt has been made to predict the ground vibration using an Artificial Neural Network models (ANN) by single, two, and large number inputs of blasting parameters, which have an effect on the ground vibration. Comparison between neural net work models to each other and also to conventional statistical regression models has been done. It has been found that, the prediction is better by increasing the variable inputs of neural network and it is much more accurate than empirical statistical regression model.

Several hundred limestone samples representing eight different deposits within Egypt have been evaluated and results indicate that some of the deposits are adequate for use as highway pavement construction materials. The evaluation included tests on index properties, strength, chemical, petrographic and resistance-to-abrasion. The suitability or adverse features of the eight limestone deposits have been evaluated and the various engineering characteristics are discussed, based on a rating scheme, recommendations are made for the use of selected limestones as pavement materials in Egypt.

Several hundred limestone samples representing eight different deposits within Egypt have been evaluated and results indicate that some of the deposits are adequate for use as highway pavement construction materials. The evaluation included tests on index properties, strength, chemical, petrographic and resistance-to-abrasion. The suitability or adverse features of the eight limestone deposits have been evaluated and the various engineering characteristics are discussed, based on a rating scheme, recommendations are made for the use of selected limestones as pavement materials in Egypt.

This paper is aimed at investigating the nitric oxide (NO) removal using dielectric barrier discharges (DBD) in a multi-rod reactor stressed by ac and pulse high voltages. The effects of various parameters (the voltage amplitude, frequency, gas flow rate, use of the γ-alumina pellets and the voltage type) on the discharge power and NO removal rate have been studied experimentally in the multi-rod DBD reactor. When the reactor was filled with γ-alumina pellets, improvement in NO removal rate was observed. The pulse voltage gives higher NO removal rate in comparison with ac voltage at the same energy density. Records of the discharge photograph and the emission intensity have been made at varying voltage amplitude, frequency, and gas flow rate. The records confirm the dependency of the discharge power on these parameters.

This paper is aimed at investigating the nitric oxide (NO) removal using dielectric barrier discharges (DBD) in a multi-rod reactor stressed by ac and pulse high voltages. The effects of various parameters (the voltage amplitude, frequency, gas flow rate, use of the γ-alumina pellets and the voltage type) on the discharge power and NO removal rate have been studied experimentally in the multi-rod DBD reactor. When the reactor was filled with γ-alumina pellets, improvement in NO removal rate was observed. The pulse voltage gives higher NO removal rate in comparison with ac voltage at the same energy density. Records of the discharge photograph and the emission intensity have been made at varying voltage amplitude, frequency, and gas flow rate. The records confirm the dependency of the discharge power on these parameters.

Stress-grading systems are essential for the suppression of corona in the end-turn zone of high voltage rotating machines. Unfortunately, design of stress-grading systems in industry is almost entirely based on experimental trial-and error techniques. This paper introduces a novel graphical user interface (GUI) model for the selection and design of stress-grading systems of high voltage rotating machines. The GUI model is based on two major design approaches for stress-grading systems: i: minimization of power-loss and, ii: time-domain analysis of nonlinear stress-grading systems using the describing function method. Comprehensive codes written in both FORTRAN and MATLAB® were developed for the purpose of design and analysis of linear and nonlinear stress-grading systems of high voltage rotating machines. A GUI was developed to enable the design engineer to select analyze and optimize stress-grading systems. This graphical front-end to FORTRAN and MATLAB® codes utilizes built-in functionality of MATLAB® to create graphical interface objects, interface with compiled FORTRAN functions, and generate design and analysis reports based on the data gathered from the source codes.

This paper introduces a new approach for the design and analysis of nonlinear stress-grading systems for high voltage rotating machines. The method is based on the simulation and modeling of stress-grading systems using a nonlinear lumped circuit model. The nonlinear model is analyzed in the time domain using the describing function method. The model generates the time variation of the resistances as well as the surface electric field and potential and ultimately converges to the optimal design parameters of the stress-grading system. The model is iterative and adaptive where a deviation from the nominal uniform field and the upper and lower bounds on the resistance values as well as bounds on the nonlinearity factor can be set to generate optimal design parameters of the stress-grading system.

The use of stress-grading systems proved to be essential to suppress corona in the end-turn zone of high voltage machines. Moreover, power dissipation in the end-turn region is believed to be a major factor in the deterioration process of surface field grading systems. This paper introduces two novel techniques for the design and analysis of both linear and nonlinear corona-suppression systems of high voltage machines. The first technique is based on the design of linear stress-grading systems through power-loss minimization and equalization of electric field along the end-turn zone. The second technique is based on the simulation, modeling and analysis of nonlinear stress-grading systems in the time domain using the describing function method. This model generates the time variation of the resistances as well as the surface electric field and potential and ultimately converges to the optimal design parameters of the stress-grading system.

It is essential to use stress-grading systems to suppress corona in the end-turn zone of high voltage machines, which ensure uniform electric field distribution along the end-turn region. Since power dissipation is a major factor in the deterioration process of the grading systems, it is necessary to account for the power loss in the design these systems. This paper presents a novel technique for the design of a linear resistive stress-grading system for high voltage stator winding. This technique is based on minimization of the power loss through the stress-grading system along with equalization of potential along the end-turn zone. A one-dimension lumped circuit model was used and a non-linear constrained optimization algorithm is programmed using MATLAB®. Different discretizations of the grading system are investigated. The lumped circuit model was realized in an experimental setup that confirmed the results of the proposed technique.