A brake hardware-in-the-loop simulation (HILS) system for a railway vehicle is widely applied to estimate and validate braking performance in research studies and field tests. When we develop a simulation model for a full vehicle system, the characteristics of all components are generally properly simplified based on the understanding of each component's purpose and interaction with other compo...

In the present work, utilizing the two-dimensional equations of an incompressible inviscid fluid and the reductive perturbation method, we studied the propagation of weakly nonlinear waves in water of variable depth. For the case of slowly varying depth, the evolution equation is obtained as a variable-coefficient Korteweg–de Vries (KdV) equation. A progressive wave type of solution, which sati...

the current study aims at investigating women’s sense of social security and factors influencing it in mashhad city in 2006. the population of the study includes women above 15 years old from 12 different districts in mashhad. the sample size, based on cluster sampling technique, was 360 persons. sense of security is having mental peace against those dangers and problems which threatens a perso...

Perforated fluid distribution pipes have been widely used in agriculture, water supply and drainage, ventilation, the chemical industry, and other sectors. The momentum equation for variable mass flow with a variable exchange coefficient and variable friction coefficient was developed by using the momentum conservation method under the condition of a certain slope. The change laws of the variab...

this study is performed in order to study the effect of technical- vocational training on trainee productivity in industrial sector of khorasan and preferring suitable solutions in this field. so labor productivity model was estimated for khorasan industry in period 1985 to 2004. in this model, effects of different variables were investigated on productivity of labor, variables such as: relatio...

The general variable coefficient cylindrical/spherical KdV equation has been investigated by using the simplified homogeneous balance method. It proven that if its coefficients satisfy certain constraint conditions, then a nonlinear transformation converts solution of quadratic form into equation. admits series solutions expressed exponential functions, therefore one soliton-like and multi can ...