Jan De Prins

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Detecting the dominant normal directions to the decision surface is an established technique for feature selection in high dimensional classification problems. Several approaches have been proposed to render this strategy more amenable to practice, but they still show a number of important shortcomings from a pragmatic point of view. This paper introduces a(More)
JAMES WHEELIS RIELY: Applications of Abstraction for Concurrent Programs (Under the direction of Jan Prins and Rance Cleaveland) We study the use of abstraction to reason operationally about concurrent programs. Our thesis is that abstraction can profitably be combined with operational semantics to produce new proof techniques. We study two very different(More)
We have developed an unbalanced tree search problem to evaluate the ease of programming a parallel application requiring dynamic load balancing and to benchmark the performance of such an application on a variety of parallel systems. Here we describe the benchmark, and report on its implementation using Unified Parallel C (UPC). We then examine the(More)
We describe a method for protein family identification using a graph representation of proteins. The method incorporates a novel fast subgraph isomorphism method based on a graph index to query a new structure for occurrences of family fingerprints and to assign it to a protein family with a confidence value. This method can provide an independent(More)
Most theoretical work done on gas leakage in compressors is concerned with quasi one-dimensional steady-state models. Four of these, each quite different in mathematical formulation and solution strategy, have been implemented and tested. Two experiments reported in literature were used to validate the models. The results show that chocking is likely to(More)
Silica high-performance liquid chromatographic separation of phospho- and sphingolipids of biological origin using a mobile phase containing phosphoric acid leads to gradual hydrolysis of plasmalogens during their passage through the column. The resulting 2-acyl lyso analogues give rise to peaks that tail in the direction of the parent intact plasmalogen.(More)
A comparison between four quasi one-dimensional steady-state gas leakage models, presented in a parallel paper, showed that none of them proved to be satisfactory. The results suggest that the modeling of the wall shear stress is the main flaw in the models. By fitting the shear stress to experimental data, an attempt was made to find a more acceptable(More)
A numerical optimization of the suction valve of a large reciprocating compressor has been carried out as a case study, using a combination of a compressor simulation program and a genetic optimization algorithm. This optimization algorithm is based on the theory of biological evolution: survival of the fittest. The compressor simulation program solves the(More)
This paper presents a model for gas leakage that takes the development of the velocity profile into account. It includes the physical ideas behind the model, a brief discussion of the mathematical approach and a comparison with experimental data.
The understanding of leakage flows is considerably poor when one considers the large efficiency and capacity losses that leakage induces in compressors. An important reason for this is that few compressor engineers seem to comprehend the features of this type of flow that affect the mass flow rate. This paper presents a coherent qualitative picture of(More)