Positions, short-covering

Short-covering of positions by market makers or speculative sellers, when they are stock-driven trades. 

Eq. (1) would correspond to a constant energy, constant volume, or micro-canonical simulation scheme. There are various approaches to extend this to a canonical (constant temperature), or other thermodynamic ensembles. (A discussion of these approaches is beyond the scope of the present review.) However, in order to perform such a simulation there are several difficulties to overcome. First, the interactions have to be determined properly, which means that one needs a potential function which describes the system correctly. Second, one needs good initial conditions for the velocities and the positions of the individual particles since, as shown in Sec. II, simulations on this detailed level can only cover a fairly short period of time. Moreover, the overall conformation of the system should be in equilibrium. 

The term assault -weapon can be confusing. Originally, it was a military term for a fully automatic rifle (such as the M-16) that could also be fired in short bursts. The purpose of these weapons (first introduced by the Germans in World War II and quickly adopted by the Soviets in the form of the AK-47), is primarily to give an infantry soldier enough firepower to cover an assault on an enemy position. 

---