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Directed networks find many applications in computer science, social science and biomedicine, among others. In this paper we propose a new graph mining algorithm that is capable of locating all frequent induced subgraphs in a given set of directed networks. We present an incremental coding scheme for representing the canonical form of a graph, study its properties, and develop new techniques for pattern generation suitable for directed networks. We prove that our algorithm is complete, meaning that no qualified pattern is missed by the algorithm. Furthermore, our algorithm is correct in the sense that all patterns found by the algorithm are frequent induced subgraphs in the given networks. Experimental results based on synthetic data and gene regulatory networks show the good performance of our algorithm, and its application in network inference. [ABSTRACT FROM AUTHOR]

This paper explores the idea of closed world specialisation (CWS). While traditional CWS is performed as a postprocessing step, we propose two different approaches to incorporating it into the induction process of a bottom-up inductive logic programming system. The motivation comes from the fact that using CWS as a postprocessing step is incapable of solving problems in which the negated part of the hypothesis is crucial. We apply the proposed approaches to the ProGolem bottom-up ILP system. We give examples of problems, where classical CWS fails to find a complete and consistent solution, whereas the proposed approaches succeed. Tests on real-world datasets show that the proposed approaches perform at least as well as regular CWS, while being better in terms of predictive accuracy in some cases. We also point out some weaknesses of different CWS approaches. [ABSTRACT FROM AUTHOR]

The paper of Andrzej Grzegorczyk [19] on hierachy of the primitive recursive classes dates for 1953. This is the most frequently cited article of Polish author in computer science literature, having some hundreds citations. Moreover, many citations are in the papers of eminent computer scientists e.g. [10,24,33,34,31], sometimes the laureates of prestigious awards. In this paper we make an attempt to present Andrzej Grzegorczyk as a computer scientist. [ABSTRACT FROM AUTHOR]

The paper deals with Knowledge‐based Information Systems (IS) engineering. The Enterprise management functions, processes and their interactions are considered as the major components of the domain knowledge. This is the peculiarity of this approach to Enterprise modelling for IS engineering. The resulting framework for Enterprise modelling and Knowledge‐based IS engineering – Enterprise meta‐model (EMM) – is developed and presented in this paper. The architecture of the advanced CASE system is also discussed in this paper. [ABSTRACT FROM AUTHOR]

M_parameters extend Java by allowing methods to have methods as parameters. [8] furnishes a semantics of m parameters and applications in OO programming. In this paper, we present an implementation of the extended language based on program preprocessing. We also discuss the integration of the extended programs with ordinary Java programs, and hence Java API. Furthermore, mc parameters are defined: they are a variant of m parameters for which the class hierarchy of the method passed as parameter must be provided in the formal and actual parameter. Semantics for mc parameters is given but, in this case, an implementation with callbacks [20] is proposed. Eventually, we discuss how mc_parameters deal with overloaded methods. [ABSTRACT FROM AUTHOR]

Subtyping is a basic concept in object-oriented languages. It supports subsumption but, unfortunately, it does not support inheritance of binary methods, i.e., methods taking another argument of type Self? – the same type as the object itself. For this reason, a relation, called matching, on recursive object types has been proposed. This relation does not support subsumption but it allows to inherit binary methods. Two different definitions of matching, called F-bounded and higher-order subtyping, have been proposed and discussed. It was shown that the higher-order interpretation has better theoretical properties, i.e., it leads to a reflexive and transitive matching relation. In this paper we concentrate on two problems in languages with self types and matching based on the higher-order interpretation. We show that the flexibility of self types may not allow the programmer to define certain classes and/or methods which are based on constant values. Furthermore, the higher-order interpretation, especially in the context of bounded quantification, is too restrictive. We argue that a language should be based on both versions of matching and a notion of a type This distinguished from the type Self. [ABSTRACT FROM AUTHOR]

This paper proposes a classification system based on a hierarchical modular architecture. Such an architecture is designed to address high-dimensional classification problems, that are characterized by a high number of input features and a large number of classes. The hierarchical approach decomposes a "many-class" problem into a hierarchy of "few-class" sub-problems, while the {modular approach} allows efficient treatment of high-dimensional input spaces. Specifically, each classifier in the hierarchy has a modular structure. Each module is implemented as a neuro-fuzzy network that operates on a distinct region of the input space. As an application, the proposed architecture is employed to solve the problem of classifying musical instruments from the sound they produce. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the problem of gender classification using frontal facial images. Four different classifiers, namely K-means, k-nearest neighbors, Linear Discriminant Analysis and Mahalanobis Distance Based classifiers are compared. Receiver operating characteristics (ROC) curve along with the area under the convex hull (AUCH) have been utilized as the performance measures of the classifiers at different feature subsets. To measure the overall performance of a classifier with single scalar value, the new scheme of finding the area under the convex hull of AUCH of ROC curves (AUCH of AUCHS) is proposed. It has been observed that, when the number of macro features is increased beyond 5, the AUCH saturates and even decreases for some classifiers, illustrating the curse of dimensionality. We then used genetic programming to combine classifiers and thus evolved an optimum combined classifier (OCC), producing better performance than the individual classifiers. We found that using only two features, the OCC has comparable performance to that of original classifier using 20 macro features. It produces true positive rate values as high as 0.94 corresponding to false positive rate as low as 0.15 for 1: 3 train to testing ratio. We also observed that heterogeneous combination of classifiers is more promising than the homogenous combination. [ABSTRACT FROM AUTHOR]

Distributed algorithms, self-stabilizing systems in particular, are often too delicate to be argued informally. Formal proofs are much more reliable, but unfortunately are often long and complicated. Some of the complication is inherent, but some is also the result of poor notation and formalism which is not abstract enough. Improving them would make formal proofs easier to write and to understand, which will also make them less error prone. In this spirit, this paper proposes an extension of the logic UNITY with a number of new operators to model self-stabilization and a formalization of a number of useful design strategies. They should enhance the formalism offered by UNITY with better abstraction to specify and reason about self-stabilization. [ABSTRACT FROM AUTHOR]

This article presents a formal analysis of the rule refinement selection problem. There is no satisfactory methodical standard for the optimal refinement of rule bases. Current refinement systems select the best overall rule base refinements out of a set of normal, conflicting, and alternative ones, not by exact optimization procedures but rather by using local greedy heuristics. Within the last decade different research prototypes have demonstrated scientific progress in the development of rule base validation systems. In particular, several rule refinement generators have been tested. However, the optimal refinement of rule bases is an unsolved problem. This paper describes a novel global Operations Research approach to the selection of optimal rule refinements. The problem analysis and the formal description of the optimization are carried out using a well‐defined example which is developed in three steps. First, conflicting rule refinements are analyzed. Next, simple alternatives are considered. Then also the optimization with regard to alternative refinement heuristics yielding combinatorial effects termed subsumption and synergy is formalized. The mathematical analysis of the rule refinement selection problem leads to the conclusion that the introduction of a special binary relation termed ONE‐OF DISJUNCTION and the use of so‐called EITHER‐OR CONSTRAINTS enables the formulation of a binary linear maximization problem to be solved by an appropriate Operations Research procedure. Finally, it will be explored how to come up with weighted objective functions and a suitable multi‐criteria validation gain calculation. This global optimization of rule base refinement GRSP holds for every refinement selection problem and will yield a more powerful generation of rule refinement systems so that the development time for large and complex rule bases will be shortened. [ABSTRACT FROM AUTHOR]

System analysis and modeling method based on lifecycle and various attributes of object is proposed in order to support system development and reuse. This method is intended to comprehend the life cycle of an object by grasping object information as an aggregate of information for an object's attribute and by integrating a state transition for each object's attributes. In this paper, we define (1) state, (2) attribute, (3) occurrence and merging of information and substance, propose an analysis method by Extended State Transitions Diagram (STD) (Lifecycle STD/Attribute STD/Attribute Integrated STD), and describe the results of its application for wholesale as an example. [ABSTRACT FROM AUTHOR]