This paper presents two case studies of parallelization of large Natural Language Processing (NLP) applications using a parallel logic programming system (called "ACE") that automatically exploits implicit parallelism. The first system considered is Artwork, a system for semantic disambiguation, speech act resolution, and temporal reference resolution. The second system is ULTRA, a multilingual...

We discuss a scheme for hierarchical matrices with adaptive cross approximation on symmetric multiprocessing clusters. We propose a set of parallel algorithms that are applicable to hierarchical matrices. The proposed algorithms are implemented using the flat-MPI and hybrid MPI+OpenMP programming models. The performance of these implementations is evaluated using an electric field analysis comp...

Multiprocessing systems are programmed cleanly using Critical sections. When a process desires to access some shared data it first gets mutual exclusive access to critical sections for reliable outcome as processes may possibly manipulate the data. This paper presents an algorithm that can solve the problem in single processing, multiprocessing and distributed systems efficiently with minimal c...

Realistically rough stochastic realizations of subglacial bed topography are crucial for improving our understanding basal processes and quantifying uncertainty in sea-level rise projections with respect to topographic uncertainty. This can be achieved Sequential Gaussian Simulation (SGS), which is used generate multiple non-unique geological phenomena that sample the space. However, SGS very C...

Automatic Self Allocating Threads (ASAT) is proposed as a way to balance the number of active threads across a shared-memory multiprocessing system. Our approach is signiicant in that it is designed for a system running multiple jobs, and it considers the load of all running jobs in its thread allocation. In addition, the overhead of ASAT is suuciently small so that the run times of all jobs im...

The work in this thesis was carried out in the context of the Artemisia project supported by PROGRESS/STW.

Every time it is more often to audit the communications in companies to verify their right operation and to check that there is no illegal activity. The main problem is that the tools of audit are inefficient when communications are encrypted. There are hacking and cryptanalysis techniques that allow intercepting and auditing encrypted communications with a computational cost so high that it is...

This paper presents EME, a low-cost solution for a highly modular multiprocessing hardware-software environment useful in designing autonomous mobile robots. High processing capabilities, the ability to interface a large number of sensors and actuators, extensibility, redundancy and exibility are issues addressed by this environment. An autonomous robot equipped with two cameras, one for line-f...

However, for the parallelization of tasks not necessarily a multi-core processor is required. Hardware multithreading, for example, is an approach that enables parallelization also for single-core processors. Here, we deal with a basic problem of cores with pipeline architecture: cache misses or data dependencies between the instructions mean that the pipelined instruction processing has to be ...