land- phone, like mobile, internet and fax is a communication device and has network externality effect. thus as the penetration coefficient increases, the network effect improves. the transmission of information via the word of mouth is the main source of enhancing the network externalities coefficient. in this article we have investigated the factors affecting the network externality coeffici...

This paper describes an analysis of reflection and transmission of acoustic waves from an imperfectly reflecting, rough fluid–fluid interface within the Kirchhoff approximation. It presents the results of calculations of the coherent and diffuse field. This work is motivated by the fact that few explicit results of the characteristics of the scattered and transmitted wave field exist in the lit...

It is shown that the transmission line technology can be suitably used for simulating quantum mechanics. Using manageable and at the same time non-expensive technology, several quantum mechanical problems can be simulated for significant tutorial purposes. The electric signal envelope propagation through the line is governed by a Schrödinger-like equation for a complex function, representing th...

A technique to estimate the depth of surface-breaking cracks in concrete is presented. The surface wave transmission coefficient across the crack plane is determined and used to estimate the depth. A self-compensating testing scheme is applied to eliminate experimental difficulties. Here the self-compensating testing scheme is introduced, and the approach used to estimate crack depth from the m...

Transmission lines are designed to transfer electric power from source locations to distribution networks. However, their lengths are exposed to various faults. Protective relay and fault recorder systems, based on fundamental power frequency signals, are installed to isolate the faulty line and provide the fault position. However, the error is high especially in transmission lines. This work i...

Reactive pathways to nucleation in a three-dimensional Ising model at 60% of the critical temperature are studied using transition path sampling of single spin flip Monte Carlo dynamics. Analysis of the transition state ensemble (TSE) indicates that the critical nuclei are rough and anisotropic. The TSE, projected onto the free energy surface characterized by cluster size, N, and surface area, ...

Vacuum evaporated crystalline films of Zinc Selenide (ZnSe) have been characterized by using optical spectroscopy (especially transmission and absorption spectra). Thin films of ZnSe have been deposited by vacuum evaporation technique on highly clean glass substrates and their optical properties such as refractive index (n), extinction coefficient (k), and energy band gap have been studied. The...