The rotationally symmetric flow of a micropolar fluid in the presence of an infinite rotating disk has been studied numerically. The equations of motion are reduced to a system of ordinary differential equations, whic...The rotationally symmetric flow of a micropolar fluid in the presence of an infinite rotating disk has been studied numerically. The equations of motion are reduced to a system of ordinary differential equations, which in turn are solved numerically using SOR method and Simpson’s (1/3) rule. The results are calculated for different values of the parameter s (the ratio of angular velocities of disc and fluid) and the suction parameter a. Moreover, three different sets of the values of non-dimensional material constants related to micropolar behavior of the fluid have been chosen arbitrarily. The calculations have been carried out using three different grid sizes to check the accuracy of the results. The research concludes that the micropolar fluids flow resembles with that of Newtonian fluids when the material constants become close to zero. The comparison of these results is presented for possible values of the parameter s.展开更多
The origin of Mobile ad hoc network (MANET) was started in 1970 as packet radio network (PRNET), later on different researches were made on it in different ages. MANET works under no fixed infrastructure in which ever...The origin of Mobile ad hoc network (MANET) was started in 1970 as packet radio network (PRNET), later on different researches were made on it in different ages. MANET works under no fixed infrastructure in which every node works likes a router that stores and forwards packet to final destination. Due to its dynamic topology, MANET can be created anywhere, anytime. As there are limited resources in MANET so it faces many problems such as security, limited bandwidth, range and power constraints. Due to this, many new routing protocols are proposed. This article examines different techniques to manage congestion control, security issues, different layers attacks, routing protocols and challenges that are faced by MANET.展开更多
文摘The rotationally symmetric flow of a micropolar fluid in the presence of an infinite rotating disk has been studied numerically. The equations of motion are reduced to a system of ordinary differential equations, which in turn are solved numerically using SOR method and Simpson’s (1/3) rule. The results are calculated for different values of the parameter s (the ratio of angular velocities of disc and fluid) and the suction parameter a. Moreover, three different sets of the values of non-dimensional material constants related to micropolar behavior of the fluid have been chosen arbitrarily. The calculations have been carried out using three different grid sizes to check the accuracy of the results. The research concludes that the micropolar fluids flow resembles with that of Newtonian fluids when the material constants become close to zero. The comparison of these results is presented for possible values of the parameter s.
文摘The origin of Mobile ad hoc network (MANET) was started in 1970 as packet radio network (PRNET), later on different researches were made on it in different ages. MANET works under no fixed infrastructure in which every node works likes a router that stores and forwards packet to final destination. Due to its dynamic topology, MANET can be created anywhere, anytime. As there are limited resources in MANET so it faces many problems such as security, limited bandwidth, range and power constraints. Due to this, many new routing protocols are proposed. This article examines different techniques to manage congestion control, security issues, different layers attacks, routing protocols and challenges that are faced by MANET.
