We study the supergravity solutions describing non-extremal enhançons. There are two branches of solutions: a ‘shell branch’ connected to the extremal solution, and a ‘horizon branch’ which connects to the Schwarzschild black hole at large mass. We show that the shell branch solutions violate the weak energy condition, and are hence unphysical. We investigate linearized perturbations of the hor...

This paper is concerned with a generalization of classical inventory models (with xed ordering costs) that exhibit (s; S) policies. In our model, the distribution of demands in successive periods is dependent on a Markov chain. The model includes the case of cyclic or seasonal demand. The model is further extended to incorporate some other realistic features such as no ordering periods and stor...

We consider the effects of the Faddeev-Popov determinant in the Coulomb gauge on the confinement properties of the QCD vacuum. We show that the the determinant is needed to regularize the otherwise divergent functional integrals near the Gribov horizon but still enables large field configurations to generate IR enhanced running coupling. The physical gluon propagator is found to be strongly sup...

The payoff distribution pricing model (PDPM) of Dybvig [13] is a powerful tool for measuring the inefficiency of any investment strategy in a multiperiod setting. In this study, we extend the PDPM in three major ways. Firstly, we develop an operational formula for computing the inefficiency amount of a strategy. Secondly, we use six different investment horizons spanning from one month to five ...

Brownian motion is used to model the uncertainty in the motion of cars on a highway. The probability of collision of two adjacent cars within a xed horizon is calculated and its implications are discussed. Moreover, the probability of collision in the presence of emergency braking is also obtained by modeling the occurrence of emergency braking as a Poisson process.

Model predictive control (MPC) based methods are gaining more and more attention in power converters and electrical drives. Nevertheless, high computational burden of MPC is an obstacle for its application, especially when the prediction horizon increases extends. At the same time, increasing the prediction horizon leads to a superior response. In this paper, a long horizon MPC is proposed to c...

We consider space-times which in addition to admitting an isolated horizon also admit Killing horizons with or without an event horizon. We show that an isolated horizon is a Killing horizon provided either (1) it admits a stationary neighbourhood or (2) it admits a neighbourhood with two independent, commuting Killing vectors. A Killing horizon is always an isolated horizon. For the case when ...

introduction: playa is one of the most important landscapes in arid regions which covers about 1% of the world's total land area. study of playas is important from different points of view especially pedology, sedimentology, mineralogy, environmental geology, groundwater and surface water chemistry. more than 60 playas have been identified in iran. considering the fact that playas and surroundi...