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Log-periodic antennas have high electrical characteristics over a wide frequency range. The large length of the antennas is their significant disadvantage caused by the fact that each active region consisting of several radiators operates in a narrow frequency range. To extend this range, it is proposed to use radiators with concentrated capacitive loads, providing in-phase…

Sentiment analysis is one of the most popular information extraction tasks both from business and research prospective. From the standpoint of research, sentiment analysis relies on the methods developed for natural language processing and information extraction. One of the key aspects of it is the opinion word lexicon. Product’s feature from online reviews is an…

CdTe-based photovoltaic (PV) cells provide the lowest EBPT (energy payback time) and emit less amount of GHG (green house gases) among different types of PV cells. Thus, it is very essential to enhance the efficiency of CdTe-based solar cells. A high efficiency CdTe/CdS p-i-n heterostructure solar cell is designed and the performance of the cell…

Reliable operation of a power transformer with a certain load depends on the technical condition of individual construction parts and the ability to prevent defects that can cause a failure. During the lifecycle of a transformer, valuable data is constantly accumulated, which forms the basis for technical or risk assessment of the equipment. Therefore it…

Feature extraction is taking a very vital and essential part of bio-signal processing. We need to choose one of two paths to identify and select features in any system. The most popular track is engineering handcrafted, which mainly depends on the user experience and the field of application. While the other path is feature learning,…

The background of the article lies in South Eastern Finland, in Lappeenranta, where an active University campus has attracted a group of ICT startups as well as SME’s in the field to collaboration. The novel education approach also has another remarkable role as a developer and source of innovation. An experimental development ecosystem (EDE), where…

Quality assurance of modern-day safety-critical systems is continually facing new challenges with the increase in both the level of functionality they provide and their degree of interaction with their environment. We propose a novel selection method for black-box regression testing on the basis of machine learning techniques for increasing testing efficiency. Risk-aware selection decisions are…

To advance Java programming educations, we have developed the Java Programming Learning Assistant System (JPLAS) that provides the code writing problem. This problem asks a student to write a source code to satisfy the specification of a given assignment, where the correctness is verified by running test code on JUnit. For a novice student, a…

Hereby in this paper, we are going to refer image classification. The main issue in image classification is features extraction and image vector representation. We expose the Bag of Features method used to find image representation. Class prediction accuracy of varying classifiers algorithms is measured on Caltech 101 images. For feature extraction functions we evaluate…

In this paper, we discuss the solvability of the nonlinear parabolic systems associated to the nonlinear parabolic equation: \(\frac{\partial b_{i}(x,u_{i})}{\partial t} -div(a(x,t,u_{i},\nabla u_{i}))- \phi_{i}(x,t,u_{i})) +f_{i}(x,u_{1},u_{2})=0\) where the function  \(b_{i}(x,u_{i})\) verifies some regularity conditions, the term \(\Big(a(x,t,u_{i},\nabla u_{i})\Big)\) is a generalized Leray-Lions operator and \(\phi_{i}\) is a Caratheodory function assumed to be  Continuous on \(u_i\) and satisfy only a…

In this work, we will prove the existence of bounded solutions for the nonlinear elliptic equations \(- div(a(x,u,\nabla u)) = g(x,u,\nabla u) -divf,\) in the setting of the weighted Sobolev space \(W^{1,p}(\Omega,w)\) where \(a\), \(g\) are Caratheodory functions which satisfy some conditions and \(f\) satisfies suitable summability assumption.

In this paper, we present a novel secure cryptosystem for direct encryption of color images, based on an iterative mixing spread over three rounds of the R, G and B color channels and three enhanced chaotic maps. Each round includes an affine transformation that uses three invertible matrices of order 2 _ 2; whose parameters…

This paper proposed the identification of the proper placement of UPFC (Unified Power Flow Controller) using a series of methodological numeric simulations to improve voltage stability. For this purpose, the critical zone of the system is determined, then, comparative analyses depending on different emplacements of UPFC are performed. The dynamic model of UPFC and the…

This paper presents an analysis of a parallel connection of one synchronous generator and one self-excited induction generator that feeds a resistive load and an Induction Motor. The system voltage and frequency are controlled by a voltage control loop and a speed control loop connected to synchronous generator. The induction generator speed is controlled by…

In this paper, we prove the existence of a solution of the strongly nonlinear degenerate \(p(x)\)-elliptic equation of type: \(\mathcal{(P)}\left\{\begin{array}{rl} - div\; a(x,u,\nabla u) +g(x,u,\nabla u)& = f \quad in \;\Omega, \\ u = 0 \quad on \quad \partial\Omega, \end{array}\right.\) where \(\Omega\) is a bounded open subset of \( I\!\!R^{N}, N\geq 2, a\) is a…

This paper proposes the modeling and control of a Solid-State Transformer using a three-stage conversion topology. First, a rectification stage is used, where a three-phase high-voltage AC signal is converted to a DC level; this stage is then followed by a DC-DC converter, and finally an inverter is used to convert the DC into a…

The antenna proposed is a new geomantic structure of Ultra-Wideband (UWB) Anti- Podal Vivaldi antenna (AVA). It remarkably offers an attractive performance over the bands of cellular networks. However, its benefits are not limited only in particular applications, whereas radar imaging, mining detection, the biomedical science in the heating of brain cancer tumor and treatment,…

The objective of this paper is to investigate the use of the 1-D wavelet analysis to extract several patterns from signals data sets collected from healthy and faulty input-output signals of control systems as a preliminary step in real-time implementation of fault detection diagnosis and isolation strategies. The 1-D wavelet analysis proved that is an…

Economic gains are generally the outcome of industrialization and consequently urbanization. However, positive fiscal index generates a negative impact on natural environment sources heaving pollutant burden on soil, air and water. Industries throw tones of contaminated water into soil and water bodies without proper treatment and create a potential threat for both living and non-living…

The increased motivation (by service providers) to offer user-centric and seamless communication services – that satisfies users’ quality of experience (QoE), has manifested a myriad of challenges in the field of wireless communication; and given the increased traffic capacity and sudden explosion of cellular devices, communication systems are constantly threatened by performance related issues –…

Cloud providers seek to maximize their market share. Traditionally, they deploy datacenters with sufficient capacity to accommodate their entire computing demand while maintaining geographical affinity to its customers. Achieving these goals by a single cloud provider is increasingly unrealistic from a cost of ownership perspective. Moreover, the carbon emissions from underutilized datacenters place an increasing…

Computer programming course that utilizes languages such as C/C++ is always packed with dreary syntax details that consume most of the students’ learning time to obtain ‘grammatically’ correct source code. Consequently, it is difficult for most of the students to apply the theory they have learned in a real life context. Thus, this project proposed…

This paper is an extended version of the paper originally presented at the International Conference on Machine Learning and Applications (ICMLA 2016), which proposes the construction of classifiers, based on the application of machine learning techniques, to identify defaulting clients with credit recovery potential. The study was carried out in 3 segments of a Bank’s…

With the increasing integration level of electronic circuits management of the generated heat became one of the most important design aspects. Beside the semiconductor components capacitors are also affected by the elevated temperature. In this paper a new thermal characterization method is proposed adopting the thermal transient measurement technique for capacitors utilizing the capacitance itself…

The problem of multi-criteria or multi-objective intercropping crop planning makes it vital to consider all related factors under the constraints that will produce the highest revenue and minimum cost. Principles of intercropping elements including soil type, plant area, plant diseases, planting and harvesting time and economics factors (e.g. price, cost) are some of the factors…