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Pattern recognition problems occur in many fields and hence effective classification algorithms are the focus of much research. In various circumstances not classification accuracy but misclassification cost minimsation is the primary goal leading to the development of cost-sensitive classification algorithms. In this paper, we show how evolutionary algorithms, in particular genetic algorithms (GAs),...
This paper presents the hybrid approach for visualization of documents sets by the combination of hierarchical clustering method, based on the Growing Hierarchical Self-Organizing Maps algorithm, and Sammon projection. Algorithms based on the self-organizing maps provide robust clustering method suitable for visualization of larger number of documents into the grid-based 2D maps. Sammon projection...
In this paper we describe the possibility for usage of generalized version of one-sided (fuzzy) concept lattices, which represents analytical method from the area of Formal Concept Analysis (FCA), for joining of several simple object-attribute models. The main advantage of the algorithm for (so-called) Generalized One-sided Concept Lattices (GOSCL) is its possibility or ability to work with various...
This paper proposes the model-free PI control design for direct current (DC) drives. A model-free PI control system structure is considered in the framework of reference tracking control using a first-order nonlinear dynamic system as a local approximation of the process model. The derivatives are estimated numerically using a Savitzky-Golay filter that solves the differentiation and also the smoothing...
A mobile ad-hoc network (MANET) is a self-configuring, self-organized, and infrastructureless network of mobile stations, connected by radio links. The challenge to ensure network's operation means to continuously maintain updated information about the network's topology, the characteristics of the radio links and security at all levels. Due to the decentralized nature of the network, this is quite...
The galvanometer-based scanners (GS) are optomechatronic devices with a wide range of applications, from industrial to biomedical imaging. They are driven with periodical and time variable signals — especially sawtooth, triangular, sine wave or signals with special variations. We approach in this paper the rejection of the effect of disturbances in order to improve the tracking performances of the...
This paper presents an approach to software maintenance effort estimation based on the analysis of software maintenance requests available in issue tracking system in a very small local software company. Over 1900 requests, collected during 19 months in 2010 and 2011, were selected for analysis. The approach takes into account: the frequency of submitted user requests for particular periods of time...
Traditional education systems are highly theoretical and almost entirely based on student knowledge memorization. Nowadays european society development is focused on practical skills, globalization and competitiveness. Existing romanian e-learning systems tend to present and explain knowledge in a spectacular way using multimedia but none of them are based on the concept of competence. The solution...
In the heterogeneous mobile networks of the future, the mobile users, equipped with multi-mode terminals, will be able to select the radio network that suits best the needs of the mobile user and of the applications running on the mobile terminal. In this work we propose a novel network selection algorithm based on fuzzy inference. Our algorithm permits a prioritization of the users by using different...
The paper proposes to define three parameters that can be associated with lumbar spine diagnosis. These parameters will further be used in a prediction software that aims to establish a treatment indication in the early stages of the medical exploration. These parameters quantifies very different conditions of the patient: pain — a very subjective parameter; the calories consumed in one day — measurable...
The main aim of this article is to establish summation formulae in form of sampling expansion series for Bessel functions Yv, Iv; and Kv, and obtain sharp truncation error upper bounds occurring in the Y-Bessel sampling series approximation. The principal derivation tools are the famous sampling theorem by Kramer and various properties of Bessel and modified Bessel functions which lead to the so-called...
We develop and analyze a new algorithm for global minimization of real Lipschitz functions. The proposed method uses a double bisection strategy and an always convergent solver of nonlinear equations. The computer implementation and performance are investigated in detail.
In this paper we introduce a finite source retrial queueing model to investigate the performance characteristics of the wireless transmission problem in sensor networks. We divide the sensors into two classes. The first one is the “Emergency” class, which performs the notification of special emergency situations (eg. fire alarms). The second one is the “Normal” class, which measures and transmits...
In this paper our aim is to use some tight lower and upper bounds for the differential quaternary phase shift keying transmission bit error rate in order to deduce accurate approximations for the bit error rate by improving the known results in the literature. The computation of our new approximate expressions are significantly simpler than that of the exact expression.
Living in the 21st century, we are exposed to vast amounts of information. ICT is becoming necessary for our everyday lives, we require the need for accessing our personal documents anywhere and anytime. This article is concentrating on the importance of unification in higher education, in terms of finding the most effective way for our students to access the curriculum. Here are presented the strategical...
The realization of an adaptive online learning environment presupposes the full consideration of the existing knowledge of the individual and their learning characteristics both in the area of course as well as learning management. Therefore during the learning process diagnostic and formative control, evaluation and assessment, with web usage mining as an efficient means, has a special significance...
U-I characteristics — or electric power — as function of electrical voltage or current — of a solar panel (PV cell or panel) gives important information for developers, engineers and users. From this reason to get U-I plot or characterization of the electric power of a solar panel plays important role at the tests. In this paper a new and easy experimental method for U-I measurement (indirectly measured...
Breast cancer is the most commonly diagnosed form of cancer in women. Pattern classification approaches often have difficulties with breast cancer related datasets as the available training data are typically imbalanced with many more benign cases recorded than malignant ones, leading to a bias in the classification and insufficient sensitivity. In this paper, we present an ensemble classification...
The paper is focusing on transmission network expansion planning (TNEP) problem solved using artificial intelligence techniques. It is divided into two parts. The 1st part is dedicated to the particle swarm optimization (PSO) and genetic algorithm (GA) concepts and mechanisms. The mathematical models and the associated software tool are also presented. Practical considerations are discussed. The 2...
In this paper a novel implementation of the adaptive controllers designed by the use of Robust Fixed Point Transformation is studied. Instead guaranteeing global stability the so designed controllers work smoothly in a bounded region of operation. Both the limits of this region as well as the performance of the controller depends on the basic component of the RFPT-based design, i.e. on the properties...
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