The log cost measure has been viewed as a more reasonable method of measuring the time complexity of an algorithm than the unit cost measure. The more widely used unit cost measure becomes unrealistic if the algorithm handles extremely large integers. Parallel machines have not been examined under the log cost measure. In this paper, we investigate the Parallel Random Access Machine under the l...

We prove that every outerplanar graph can be optimally edge-coloured in polylogarithmic time using a polynomial number of processors on a parallel random access machine without write conflicts (P-RAM).

Physical and generic models that analytically couple the array architecture of CMOS SRAMs with the wire lengths and fan-outs along critical paths to decode and sense data are reported. Verified to be accurate with published SRAMs, these models enable the design of optimal array architectures to minimize total access time by balancing communication distance limited wire delays with fan-out and a...

In this paper, we investigate the optimisation of the Random Access CHannel (RACH) of the UMTS FDD system in terms of generated interference. Conditional on open loop measurements, we search the best initial energy of the RACH in order to reduce the multiple access interference while keeping a reasonable mean access time.

It is known that in some cases a Random Access Machine (RAM) benefits from having an additional input that is an arbitrary number, satisfying only the criterion of being sufficiently large. This is known as the ARAM model. We introduce a new type of RAM, which we refer to as the Arbitrary Sequence RAM (ASRAM), that generalises the ARAM by allowing the generation of additional arbitrary large nu...

The general problem of allocating the capacity of a communication channel to a population of geographically distributed terminals is considered. The main focus is on the queueing problems that arise in the analysis of random access resolution algorithms. The performance measures of interest are the channel efficiency and the mean response time. The nature of known solutions for various random a...

We consider the problem of representing, in a space-efficient way, a function f : S → Σ such that any function value can be computed in constant time on a RAM. Specifically, our aim is to achieve space usage close to the 0th order entropy of the sequence of function values. Our technique works for any set S of machine words, without storing S, which is crucial for applications. Our contribution...

Let K be an imaginary quadratic field and f an integral ideal. Denote by Cl(f) the ray class group of f. For every non-trivial character χ of Cl(f), we show that L(1, χ)/π is transcendental. If f = f, then complex conjugation acts on the character group of Cl(f). Denoting by Ĉl(f) + the orbits of the group of characters, we show that the values L(1, χ) as χ ranges over elements of Ĉl(f) + are l...

Secure computation of a random access machine (RAM) program typically entails that it be first converted into a circuit. This conversion is unimaginable in the context of big-data applications where the size of the circuit can be exponential in the running time of the original RAM program. Realizing these constructions, without relinquishing the efficiency of RAM programs, often poses considera...