Derlis Gregor

Distributed urban traffic applications based on CORBA event services

Intelligent transportation systems (ITS) in urban environments are based today on modern embedded systems with enhanced digital connectivity and higher processing capabilities, supporting distributed applications working in a cooperative manner. This paper provides an overview about modern cooperative ITS equipments and presents a distributed application to be used in an urban data network. As a case example, an application based on an embedded CORBA-compliant middleware layer and several computer vision equipments is presented. Results prove the feasibility of distributed applications for building intelligent urban environments.

A methodology for structured ontology construction applied to intelligent transportation systems

The number of computers installed in urban and transport networks has grown tremendously in recent years, also the local processing capabilities and digital networking currently available. However, the heterogeneity of existing equipment in the field of ITS (Intelligent Transportation Systems) and the large volume of information they handle, greatly hinder the interoperability of the equipment and the design of cooperative applications between devices currently installed in urban networks. While the dynamic discovery of information, composition and invocation of services through intelligent agents are a potential solution to these problems, all these technologies require intelligent management of information flows. In particular, it is necessary to wean these information flows of the technologies used, enabling universal interoperability between computers, regardless of the context in which they are located. The main objective of this paper is to propose a systematic methodology to create ontologies, using methods such as a semantic clustering algorithms for retrieval and representation of information. Using the proposed methodology, an ontology will be developed in the ITS domain. This ontology will serve as the basis of semantic information to a SS (Semantic Service) that allows the connection of new equipment to an urban network. The SS uses the CORBA standard as distributed communication architecture. We propose a methodology to build ontologys in the domain of ITS (Intelligent Transportation Systems).We have proposed: DPK (Discrimination of Paragraphs with Keywords) and IRWDP (Retrieval with Weighted Data in Paragraphs).The two new methods proposed, allow reducing the sample size of the study.Much information irrelevant has been discarded, achieving greater performance in the ontology construction.The methodologies proposed can be used to build ontologies in any domains.

Biaxial Solar Tracking System Based on the MPPT Approach Integrating ICTs for Photovoltaic Applications

The smart grid and distributed generation based on renewable energy applications often involve the use of information and communication technology (ICT) coupled with advanced control and monitoring algorithms to improve the efficiency and reliability of the electrical grid and renewable generation systems. Photovoltaic (PV) systems have been recently applied with success in the fields of distributed generation due to their lower environmental impact where the electrical energy generation is related to the amount of solar irradiation and thus the angle of incident ray of the sun on the surface of the modules. This paper introduces an integration of ICTs in order to achieve the maximum power point tracking (MPPT) using a biaxial solar tracking system for PV power applications. To generate the references for the digital control of azimuth and elevation angles a Global Positioning System (GPS) by satellites is used which enables acquiring the geographic coordinates of the sun in real-time. As a total integration of the system a communication platform based on the 802.15.4 protocol for the wireless sensor networks (WSNs) is adopted for supervising and monitoring the PV plant. A 2.4 kW prototype system is implemented to validate the proposed control scheme performance.

A survey on unmanned aerial and aquatic vehicle multi-hop networks: Wireless communications, evaluation tools and applications

Abstract Unmanned aerial and aquatic vehicle networks have attracted the attention of the wireless communication research community in the last decade. The low manufacturing costs for developing small unmanned vehicles and the notable developments on wireless communication technologies have made possible the design of cooperative applications involving multiple unmanned aerial and aquatic vehicles. However, the design of wireless networks, which include very dynamic and complex entities like unmanned vehicles, poses many challenges. Fortunately, unmanned aerial vehicle networks applications usually resemble those of unmanned aquatic vehicle networks such as military missions, or environmental monitoring among others. With the exception of the obvious differences in the lower layers of the wireless communications protocols, valid approaches used in the aerial medium could be easily adapted to the aquatic medium. This survey presents together the main features to take into account for designing unmanned aerial and aquatic vehicle networks with the aim to help the reader to transfer valid approaches and techniques between aerial and aquatic applications. We survey the results of more than 100 references on this topic published in international conferences and journals, and we also include the results of several bibliometric analyses in order to better present the status of the art and research directions on this scientific area.

Multi-modular matrix converter topology applied to the six-phase wind energy generator

Power electronic grid-connected converter topologies are widely used as grid interface to interconnect several renewable energy sources under the concept of distributed generation systems. These converters must ensure an active and reactive flux control, minimize the current and voltage harmonic distortions and perform a proper synchronization with the electrical grid. This paper presents an analysis and theoretical validation of a multi-modular matrix converter topology applied to the six-phase wind energy generator. Simulations results based on a MatLab/Simulink simulation environment will be discussed and the most relevant characteristics of the proplogosed topology will be highlighted.

Reduced-order Observer Analysis in MBPC Techniques Applied to the Six-phase Induction Motor Drives

Raul Gregor, Jorge Rodas, Derlis Gregor and Federico Barrero (2015). Reduced-order Observer Analysis in MBPC Techniques Applied to the Six-phase Induction Motor Drives, Induction Motors - Applications, Control and Fault Diagnostics, Dr. Raul Gregor (Ed.), ISBN: 978-953-51-2207-4, InTech, DOI: 10.5772/60778. Available from: http://www.intechopen.com/books/induction-motors-applications-control-and-fault-diagnostics/reduced-order-observer-analysis-in-mbpc-techniques-applied-to-the-six-phase-induction-motor-drives

A Path Planning Approach of an Autonomous Surface Vehicle for Water Quality Monitoring Using Evolutionary Computation

The path planning of an autonomous surface vehicle in a lake for environmental monitoring has been modeled as a particular case of the traveling salesman problem, in which the ASV should visit a ring of beacons deployed at the shore of the lake for delivering the collected data. For achieving a complete representation of the lake, the distance traveled should be maximized instead of minimized as in the classic traveling salesman problem. The evolutionary technique known as genetic algorithm is applied for finding the optimal solution. The simulations show promising results even in the case that some constrains are included in the problem.

Implementation of a low cost UAV for photogrammetry measurement applications

The increasing civilian demand for autonomous aerial vehicle in the professional markets led to an abundance of inexpensive navigational hardware platforms and vehicle prototypes. Current photogrammetry-based applications require crisp and precise positioning of images so that the process does not fails. Also systems adaptable to the circumstances for better effectiveness, vehicles capable of vertical take-off and landing with flight autonomy to define a clear flight path necessary for images order and photogrammetry process relief. In this paper, a simple and low cost design of an unmanned aerial vehicle (UAV) able to satisfy the aforementioned requirements is presented. By structural analysis, building techniques and flight principles, the advantages of a rotary wing were subject to several tests. An state-of-art graphic programming with predefined code plus a high performance development hardware allowed the implementation of a control system and spatial positioning. Furthermore, the integration of a low cost digital camera to the vehicles body allowed the realization of the aerial photogrammetry-based mapping task in reduced areas, a potential application for the type of UAV presented in this paper, with great expectation in the study of topology in significantly less time for collecting and analyzing data.

Design and Implementation of an FPGA-based Real-time Simulator for a Dual Three-Phase Induction Motor Drive

This paper presents a digital hardware implementation of a real-time simulator for a multiphase drive using a field-programmable gate array (FPGA) device. The simulator was developed with a modular and hierarchical design using very high-speed integrated circuit hardware description language (VHDL). Hence, this simulator is flexible and portable. A state-space representation model suitable for FPGA implementations was proposed for a dual three-phase induction machine (DTPIM). The simulator also models a two-level 12-pulse insulated-gate bipolar transistor (IGBT)-based voltage-source converter (VSC), a pulse-width modulation scheme, and a measurement system. Real-time simulation outputs (stator currents and rotor speed) were validated under steady-state and transient conditions using as reference an experimental test bench based on a DTPIM with 15 kW-rated power. The accuracy of the proposed digital hardware implementation was evaluated according to the simulation and experimental results. Finally, statistical performance parameters were provided to analyze the efficiency of the proposed DTPIM hardware implementation method.

Power flux model-based analysis of a micro-grid connected PV system with storage energy unit

The uncertainty of the irradiation and temperature availability in renewable energy sources, especially in photovoltaic (PV) systems in distributed generation topology, often involves the use of storage energy unit. The power flux variability from the PV systems to the storage energy unit due to an irradiation and temperature variations produce a variation of the flux power from the storage energy unit to the micro-grid. This article proposed an analysis of a micro-grid connected PV system (with battery bank unit), considering a single line power flux model with modifications, under different weather conditions. The effectiveness of proposed model and analysis method will be verified by a set of simulation results, considering the parameters of a real 2:4 kW PV system.