Search results for " processing"
showing 10 items of 7549 documents
A frequency compensation algorithm of four-wheel coherence random road
2013
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/986584 Open access The road surface roughness is the main source of kinematic excitation of a moving vehicle, which has an important influence on vehicle performance. In recent decades, random road models have been widely studied, and a four-wheel random road time domain model is usually generated based on the correlation of the four-wheel input, in which a coherence function is used to describe the coherence of the road input between the left and right wheels usually. However, during our research, there are some conditions that show that…
Structural Health Monitoring Procedure for Composite Structures through the use of Artificial Neural Networks
2015
In this paper different architectures of Artificial Neural Networks (ANNs) for structural damage detection are studied. The main objective is to investigate an ANN able to detect and localize damage without any prior knowledge on its characteristics so as to serve as a real-time data processor for Structural Health Monitoring (SHM) systems. Two different architectures are studied: the standard feed-forward Multi Layer Perceptron (MLP) and the Radial Basis Function (RBF) ANNs. The training data are given, in terms of a Damage Index ℑD, properly defined using a piezoelectric sensor signal output to obtain suitable information on the damage position and dimensions. The electromechanical respon…
Sensorless Control of PMSM Fractional Horsepower Drives by Signal Injection and Neural Adaptive-Band Filtering
2012
This paper presents a sensorless technique for permanent-magnet synchronous motors (PMSMs) based on high-frequency pulsating voltage injection. Starting from a speed estimation scheme well known in the literature, this paper proposes the adoption of a neural network (NN) based adaptive variable-band filter instead of a fixed-bandwidth filter, needed for catching the speed information from the sidebands of the stator current. The proposed NN filter is based on a linear NN adaptive linear neuron (ADALINE), trained with a classic least mean squares (LMS) algorithm, and is twice adaptive. From one side, it is adaptive in the sense that its weights are adapted online recursively. From another si…
Factors Affecting Attrition among First Year Computer Science Students: the Case of University of Latvia
2015
<p class="R-AbstractKeywords"><span lang="EN-GB">The purpose of our study was to identify reasons for high dropout of students enrolled in the first year of the computer science study program to make it possible to determine students, who are potentially in risk. Several factors that could affect attrition, as it was originally assumed, were studied: high school grades (admission score), compensative course in high school mathematics, intermediate grades for core courses, prior knowledge of programming. However, the results of our study indicate that none of the studied factors is determinant to identify those students, who are going to abandon their studies, with great precisio…
Configurable bandwidth imaging spectrometer based on acousto-optic tunable filter
2005
This paper presents a new portable instrument called Autonomous Tunable Filtering System (ATFS), developed for highly customisable imaging spectrometry in the VIS-NIR range. The ATFS instrument consists of an Acousto-Optic Tunable Filter (AOTF), an optical system, a Radio Frequency (RF) driver based on a Direct Digital Synthesiser (DDS) and control software. The ATFS can be attached to a variety of high-performance monochrome cameras. The system works as a spectral bandpass filter whose wavelength can be selected between 400nm and 1000nm and whose bandwidth can be adjusted between 4nm and 50nm. The filter can be tuned electronically at a very high speed and accuracy, thanks to the DDS versa…
Gabor filters in industrial inspection: a review. Application to semiconductor industry
2005
This paper focuses on reviewing some recent works of the use of Gabor filters dealing with industrial applications. After a brief recall of Gabor filter basis, the two usual uses of Gabor filters are recalled: filter bank approach and filter design approach. The third part presents recent published works domain by domain. A fourth part exposes our own work with Gabor Filters for defect detection on semiconductor. A short conclusion summarizes the paper.
Bibliometric insights into the spectroscopy research field: A food science and technology case study
2019
The food industry is in need of analytical solutions to maintain high quality and safety standards during the entire food production chain. Spectroscopy applications are targeted as a major solution due to its cost-effective, simple, efficient and multiparametric nature. Bibliometric studies provide a critical evaluation of the status of a research topic through the quantification of measurable outcomes of research activity. The main aim of this study was to use a bibliometric approach to the evaluation of the current status of the spectroscopy research applied to food science and technology. The critical evaluation of the results showed the most commonly used spectroscopy applications as w…
Spectrum sensing challenges: blind sensing and sensing optimization
2016
By any measure, wireless communications is one of the most evolving fields in engineering. This, in return, has imposed many challenges, especially in handling the hunger for higher data rates in the next generation wireless networks. Among these challenges is how to provide the needed resources in terms of the electromagnetic radio spectrum for these networks. In this regard, cognitive radio (CR) based on dynamic spectrum access (DSA) has been attracting huge attention as a promising solution for more efficient utilization of the available radio spectrum. DSA is based on finding and opportunistically accessing the free-of-use portions of spectrum. To facilitate DSA, spectrum sensing can be…
A simplified approach for load flow analysis in MV smart grids based on LV power measurements
2017
This paper presents a simplified approach for load flow analysis in medium voltage (MV) distribution networks. It is a power summation Backward/Forward (B/F) algorithm, based on measurements of active and reactive powers at low voltage (LV) side of MV/LV distribution substations. The proposed solution allows achieving good accuracy, computational efficiency and fast convergence. In order to verify the algorithm performances, simulation studies are carried out in the case of a real test system, i.e. the distribution grid of Favignana Island (Mediterranean Sea, Italy). The compatibility between simulations results and power measurements at the MV bus bars of the generating substation shows th…
Smart cameras on a chip: using complementary metal-oxide-semiconductor (CMOS) image sensors to create smart vision chips
2020
Abstract: In this chapter, we introduce the fundamental concept of smart cameras on a chip or smart vision chips that simultaneously integrate the same die image capture capability and highly complex image processing. Successive technology scaling has made possible the integration of specific processing elements designed at chip level, at column level or at pixel level. To illustrate this continuous evolution, we survey three different categories of vision chips, exploring first the pioneering works on artificial retinas, then describing the most significant computational chips, and finally presenting the most recent image processing chips able to perform complex algorithms at a high frame …