Abstract This article considers a simple model to numerically study whether thunderclaps can produce droplet coalescence in natural clouds due the relative velocities they induce between different-sized droplets. mechanism is evaluated for cloud that has both relatively small liquid content and narrow size distribution. The idealized as static environment, consisting only of water droplets air,...

Lightning is a phenomenon that is highly variable in space and time. The derivation of reliable estimates of its activity, therefore, requires statistical averaging over a large area and a considerable number of years of observation. The lightning flash density, defined as the number of flashes of a specific type occurring on or over unit area in unit time, is widely used as a statistical descr...

Software simulators have often been used to test and validate new protocols, but the high bandwidth of newly emerging ATM networks implies prohibitive memory requirements. This paper describes several simulation techniques we have devised as part of the Thunder and Lightning project to build 40 and 100 gigabit per second ATM networks.

background: xylene is known as one of the most toxic of the nervous system. the purpose of this study is to estimate the concentration of xylene in the cabin of the vehicles production in iran. also the effect of ventilation, cigarette smoking, and air freshener inside the vehicle, fuel type and car decorations on the concentration of the substance being studied.   methods: 152 vehicles pride a...