Broadcast communication plays a critical role in ad hoc networks especially vehicular communication where a large number of applications are being envisioned to use the broadcast services of IEEE 802.11p. These safety applications exchange messages at very low rates compared to voice and streaming applications but have very stringent latency requirements. The broadcast packets undergoing collis...

This paper develops a method to rigorously show the validity of continuum description for the deterministic dynamics of many interacting particles with random initial data. We consider a hard sphere flow where particles are removed after the first collision. A fixed number of particles is drawn randomly according to an initial density f0(u, v) depending on d-dimensional position u and velocity ...

Boltzmann Transport Equation [1-2] has been modelled in close conjunction with Maxwell’s equation, investigations for 2D and 3D transport carriers have been proposed. Exact solution of Boltzmann Equation still remains the core field of research. We have worked towards evaluation of 2D and 3D solutions of BTE. Application of our work can be extended to study the electromagnetic wave transport in...

This paper describes the use of polynomial chaos expansions to approximate the probability of a collision between two satellites after at least one performs a translation maneuver. Polynomial chaos provides a computationally efficient means to generate an approximate solution to a stochastic differential equation without introducing any assumptions on the a posteriori distribution. The stochast...

Collision probability (CP) evaluation and ux computation share the most time consumed in the applications based on the linearized time-independent transport equation. In this paper, parallelization for CP calculation and multi-group ux computation are investigated. Particular techniques pertinent to the two-step energy/space iterative process of solving a multigroup transport equation are descr...

A new Cartesian implementation of the direct simulation Monte Carlo (DSMC) method, named the hypersonic aerothermodynamics particle (HAP) code, is presented. This code is intended for rapid setup and simulation of rarefied flow problems, and as a framework for evaluating new physical models and numerical techniques. Unique features include the use of nonuniform Cartesian adaptive subcells, a co...

In this paper, we propose an attack method to find collisions of MD4 hash function. This attack is the improved version of the attack which was invented by Xiaoyun Wang et al [1]. We were able to find collisions with probability almost 1, and the average complexity to find a collision is upper bounded by three times of MD4 hash operations. This result is improved compared to the original result...

The distribution of interval lengths between Brownian walkers on the line is investigated. The walkers are independent until collision; at collision, the left walker disappears, and the right walker survives with probability p. This problem arises in the context of diffusion-limited reactions and also in the scaling limit of the voter model. A systematic expansion in correlation between neighbo...

We estimate the probability that a hard nucleon-nucleon collision is able to nucleate a seed of quark{gluon plasma in the surrounding hot and dense hadronic matter formed during a central collision of two large nuclei at AGS energies. The probability of producing at least one such seed is on the order of 1-100%. We investigate the in uence of quark{gluon plasma formation on the observed multipl...

The use of multibeam antennas (MBAs) in decentralized wireless networks significantly increases the throughput by improving spatial reuse and extending coverage compared with single-beam antennas. The throughput performance may, however, degrade in multipath environments due to the fact that multipath propagation increases the probability of collision among different users. Based on the probabi...