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U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x Contents AUTOMATIC CONTROL AND COMPUTERS Ciprian Lupu, Andreea Udrea, Dumitru Popescu, Cătălin Petrescu Numerical stability of adaptive control algorithms 3 Theodor Borangiu, Marian Croitoru Analysis of the data transmission in the industrial automation systems 15 Vlad Tudor Optimal loss reduction of distribution networks using a refined genetic algorithm 29 Silviu Răileanu Production scheduling in a holonic manufacturing system using the open-control concept 39 Radu Pietraru Global security model 53 Bogdan Ţigănoaia, Francisc Iacob Low distortion and robust steganography on parallel architecture CELL BE using a shared color palette and a shared hash 63 Ioan Hălălae Cellular automata with dynamical loop function as noise generators: statistical aspects (1) 73 Codrin Popa Business intelligence performance and capacity impact 83 Liliana Dobrică, Traian Ionescu, Leonard Dobrică, Sofia Elena Colesca Spatial data acquisition, management and visualization in geographic information systems 93 Bogdan Tudor Zero-knowledge protocols implemented with elliptic curves 109 Dan Popescu, Dinu Pătârniche FPGA implementation of video processing-based algorithm for object tracking 121 Marius Marcu, Dacian Tudor High-level metrics for energy efficiency evaluation 131 Fadi Issa, Ioan Dumitrache Hybrid geno-neuro system for optimization of control solution selection in multi mobile robots 147 Carmen Cristiana Bucur, Traian Aurite CAD - CAM integration optimizing data transfer between different integrated design systems in virtual enterprise environment Olumide Obe, Ioan Dumitrache 161 U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x Fuzzy control of autonomous mobile robot 173 Lucian Dragne Geometrical representation of quantum bit operations 187 ELECTRONICS AND TELECOMMUNICATIONS Mihaela Maliţa, Gheorghe M. Ştefan Many-processors & Kleene’s model 199 Gheorghiţă Pescaru Shaping security in communication infrastructures without restoring in case of malfunction 213 Daniel Gheorghică, Victor Croitoru Firewall policy management using secure Web system 227 ELECTRICAL ENGINEERING Costel Păun Aspects regarding numerical modeling of inductive heating process for low voltage electrical cables 239 Daniela Căzănaru, Andrei Szilagyi Evaluation of the shielding effectiveness of a multimode metallic cavity 249 Florin Ciuprina, Traian Zaharescu, Silviu Jipa, Ilona Pleşa, Petru V. Noţingher, Denis Panaitescu Effects of ionizing radiation on dielectric properties of LDPE-Al2O3 nanocomposites 259 Cǎtǎlina-Gabriela Popescu Discrete resistive models for multi-rate analysis of integrated analog circuits 269 Florin Ciprian Argatu, Costin Cepişcă Modeling dynamic high intensity discharge lamp characteristics 277 Ana-Maria Dumitrescu, Anca Stan, Dragoş Deaconu, Aurel Chirilă Valentin Năvrăpescu, Mihaela Albu, Gianfranco Chicco Disk-rotor servomotor fed by an AC/DC converter 285 POWER ENGINEERING Ioniţă Dăescu, Călin Mucichescu, Basarab Guzun, Daniel Morar Analysed transients during islanding operation of one HPP on its auxilliaries 297 Ioana Pisică A note on rough set theory applications in power engineering 313 Răzvan Vîjeu, Victor Athanasovici Etude experimentale de la gazeification des dechets de bois 319 U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x3 NUMERICAL STABILITY OF ADAPTIVE CONTROL ALGORITHMS Ciprian LUPU, Andreea UDREA, Dumitru POPESCU, Cătălin PETRESCU, This paper analyzes the impact of modifying the control algorithm parameters by an adaptation low on the immediate variation of the command calculated for an adaptive control structure. A method to limit negative effect of the large command variations due to the adaptation algorithm is proposed. The procedure is included in a real-time control algorithm with a model reference adaptive control mechanism designed for a class of nonlinear systems Keywords: adaptive control, real-time, application, nonlinear ANALYSIS OF THE DATA TRANSMISSION IN THE INDUSTRIAL AUTOMATION SYSTEMS Theodor BORANGIU, Marian CROITORU In this paper is presented a communication protocol designed to the data transfer among the automation systems which include programmable controllers. By introducing an additional bit to identify an address or data byte, reduce the volume of data to be processed by the MCUs slave. Decreasing the slave station interrogation cycle period, for faster update of parameters, is realized by minimizing the number of transmitted characters depending on the data type. To eliminate errors due to distortions each character is sent asynchronously. Keywords: industrial automation, data transmission, communication protocols OPTIMAL LOSS REDUCTION OF DISTRIBUTION NETWORKS USING A REFINED GENETIC ALGORITHM Vlad TUDOR The network reconfiguration in power distribution systems is realized by changing the status of sectionalizing switches, and is usually done for loss reduction or for load balancing in the system. An optimal loss reduction is obtained to maintain acceptable voltage at customer loads as well as to assure sufficient conductor and substation current capacity to handle load requirements. The topological complexity of real distribution networks implies searching through many U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x possible configurations. This combinatorial optimization problem can be resolved using the efficient refined genetic algorithm proposed in this paper. Prim’s algorithm is used with random costs for generating different spanning trees for evaluation. Keywords: power distribution network, graph optimization, refined genetic algorithm theory, loss reduction, PRODUCTION SCHEDULING IN A HOLONIC MANUFACTURING SYSTEM USING THE OPEN-CONTROL CONCEPT Silviu RĂILEANU Current advances in information technology and electronics allowed the passage from the classic centralized control approach to a fully decentralized control approach. In this context the paper proposes a new control concept in which the commands from a superior control levels are sent as recommendations and low level entities communicate between them in order to solve and optimize the task given as a recommendation. After introducing the control concept, an implementation aiming at production scheduling using a holonic approach is illustrated. The implementation was done on a job shop type production system containing multiple networked workstations. Keywords: Open-control, holonic manufacturing systems, Contract Net Protocol GLOBAL SECURITY MODEL Radu PIETRARU The material aims to present a security model for a particular class of systems, systems connected to the Internet. The originality of the model is hierarchical approach of security on three levels: level stand-alone, level local network and level Internet; and in the selection and presentation of specific security mechanisms used in each security level. Keywords: security, security model, Internet security U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x5 LOW DISTORTION AND ROBUST STEGANOGRAPHY ON PARALLEL ARCHITECTURE CELL BE USING A SHARED COLOR PALETTE AND A SHARED HASH Bogdan ŢIGĂNOAIA, Francisc IACOB This paper presents a critical steganographic analysis and a study of the Cell BE architecture. It also describes a new high capacity and robust technique for hiding information on color images. The image distortion after encoding the message is low and indistinguishable to the human eye. The encoding and decoding system uses three shared information: an image hash for protection against steganographic attacks, a pixels palette (this is the result of applying the K-means clustering algorithm, with some modifications) used for encoding the message and the dimension of one piece of the image. Parallel architecture Cell BE is used for the calculation of the hash and the pixels palette. An efficient mapping of the application on the Cell BE architecture is proposed. New Cell BE programming facilities such as double buffering, SIMD instructions, mailboxes, events, DMA transfers are used. Keywords: steganography, CELL BE, parallel architectures CELLULAR AUTOMATA WITH DYNAMICAL LOOP FUNCTION AS NOISE GENERATORS: STATISTICAL ASPECTS (1) Ioan HĂLĂLAE The present paper is the first study of the evolution of 256 cells linear cellular automata (CA) with global loop and dynamical modification of the rule. We explore the random aspects in the evolution of CA. For the definition of randomness we adjusted the one used in the algorithmic information theory for binary strings. We have tested 4 different operators aiming to find the best for obtaining more randomness in the evolution of CA (more noise). As a working tool we use experimental mathematics. Keywords: Cellular Automata with global loop, noise generation, experimental mathematics U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x BUSINESS INTELLIGENCE PERFORMANCE AND CAPACITY IMPACT Codrin POPA The actual complexity of various organizations with impact in Information Systems reveals that the development of Business Intelligence Systems must be integrated into the wider concept of the Systems Engineering. The whole project should be focus in defining all the requirements and outputs and to establish the specific pieces that compose the systems in a cycle of successive refinements. The classical software framework must be redesign in order to enable a complex approach where the functional and non-functional requirements are inter related. Based on the experience achieved in several Business Intelligence implementations, this article considers an optimal system architecture and emphasizes the proper linkage between data model and capacity and performance of the Data Warehouse Systems. Keywords: Business Intelligence, Systems Engineering, Performance, Capacity, Data Model SPATIAL DATA ACQUISITION, MANAGEMENT AND VISUALIZATION IN GEOGRAPHIC INFORMATION SYSTEMS Liliana DOBRICĂ, Traian IONESCU, Leonard DOBRICĂ, Sofia Elena COLESCA The paper discusses about a developer viewpoint regarding a geographic information system (GIS) software used in geographic data acquisition, management and visualization in a map document. GIS tools can be used effectively to overcome problems such as time consuming, costs or human errors. The purpose of this study is to design and implement a GIS-based application to be used in urban management departments. Our experience contributes to the integration of spatial data models into GIS. Also it contributes to the building of a domain knowledge base which will be used further in the software development of applications for urban management. Keywords: information systems, software development, GIS, database, georeferencing, map documents U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x7 ZERO-KNOWLEDGE PROTOCOLS IMPLEMENTED WITH ELLIPTIC CURVES Bogdan TUDOR In this paper ‘zero-knowledge’ protocols are treated in the elliptic curves perspective. The original elementes are the optimization of the algorithms, elliptic curves parameters and the Tate pairing calculus. The algorithms can be treated as a framework and through the distortion maps they can be applied on every elliptic curve pairing. Keywords: elliptic curve, Tate pairing, zero-knowledge, distortion maps FPGA IMPLEMENTATION OF VIDEO PROCESSING-BASED ALGORITHM FOR OBJECT TRACKING Dan POPESCU, Dinu PĂTÂRNICHE In this paper we propose a chromatic-based real-time single object tracking circuit implemented on a FPGA. For object isolation process the Mahalanobis distance is used. The tracking process is divided in two distinct stages: color segmentation and coordinate determination. FPGA circuit presented in this paper can track a solid color object in a scene when it receives as input a digitized PAL/NTSC stream. The basic blocks (Camera Interface Module, Color Space Converter, Reference Values, Color Segmentation, Filter Bank, Blob Tracker, UART Module, and VGA Output) where designed using VHDL as well as Verilog and implemented on a FPGA-device in order to meet the real-time constraints. Keywords: object tracking, color decomposition, Mahalanobis distance, FPGA implementation, object recognition, real time image processing U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x HIGH-LEVEL METRICS FOR ENERGY EFFICIENCY EVALUATION Marius MARCU, Dacian TUDOR This paper tries to gather together all the aspects that are important to implement or evaluate energy efficiency techniques in mobile computing devices. The main goal of our work presented in this paper is to propose, implement and validate a set of high-level metrics for energy efficiency evaluation of computing systems or Dynamic Power Management (DPM) software frameworks. Using these efficiency metrics we intend to evaluate and identify the hardware system and DPM software which are the most efficient in terms of energy to run certain application. The original aspects of the current work are the proposed evaluation framework for energy efficiency, power consumption metrics definition and classification, new evaluation test cases for energy efficiency and analysis of experimental results. Keywords: power consumption, energy efficiency, high-level metrics HYBRID GENO-NEURO SYSTEM FOR OPTIMIZATION OF CONTROL SOLUTION SELECTION IN MULTI MOBILE ROBOTS Fadi ISSA, Ioan DUMITRACHE In this paper we present a new hybrid system that combines artificial neural networks and genetic algorithms for control solution selection in multi mobile robot systems, since choosing a specific control solution for a robot to execute its required task can affect the performance of other robots, thus, the performance of the robot group as a whole. Our developed solution uses the new hybrid system in order to search for the best control solution selection for each robot in the group, in a way that achieves the optimum performance of the entire group. Keywords: genetic algorithm, artificial neural networks, multi-robot groups, performance optimization U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x9 CAD - CAM INTEGRATION OPTIMIZING DATA TRANSFER BETWEEN DIFFERENT INTEGRATED DESIGN SYSTEMS IN VIRTUAL ENTERPRISE ENVIRONMENT Carmen Cristiana BUCUR, Traian AURITE The research results published in this paper are based on a case study for shaft design made for machine tools using four Integrated Design Systems. At the beginning we elaborate the SADT diagram used in CAD/CAM Industry and data transfer. Based on these diagrams we build UML architecture. Transposing the UML in C++ Programming language in order to improve the data transfer in a Virtual Enterprise we obtain the agent source which can be transformed in an import/export agent by a programmer, then the users could import the part with historic from one IDS to another. Keywords: data transfer, CAD/CAM, UML, ISO 10303/STEP, C++ FUZZY CONTROL OF AUTONOMOUS MOBILE ROBOT Olumide OBE, Ioan DUMITRACHE Seamless navigation of autonomous mobile robots in an unstructured, nonepisodic and dynamic environment is constrain by imprecision, uncertainty, unreliability, complexity and unpredictability issues that characterize robots’ sensors and its controller. In this paper, we investigate navigation techniques for Kephera mobile robot using fuzzy logic intelligent technique. We develop Fuzzy logic controller (FCL) using different membership function types to navigate the robot. We investigate the effects of membership functions types on the performance of behaviours such as obstacle avoidance, path tracking/wall following, exploration, and target reaching. Gaussian membership function technique is found to be most efficient for mobile robot navigation. Keywords: fuzzy logic, mobile robot, obstacle avoidance, sensors U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x GEOMETRICAL REPRESENTATION OF QUANTUM BIT OPERATIONS Lucian DRAGNE Graphical representations based on geometrical transformations are a very expressive method of simulating the operations performed on quantum information processing systems. Considering a single qubit system, the proofs given in this paper justify the correspondence between a class of operations that modify the qubit state and some geometrical transformations on the Bloch sphere. The single qubit operations are expressed by the exponentiation of Pauli operators, whereas the corresponding geometrical transformations are rotations on the Bloch sphere around the coordinate axes. Keywords: quantum computing, rotation operators, Bloch sphere MANY-PROCESSORS & KLEENE’S MODEL Mihaela MALIŢA, Gheorghe M. ŞTEFAN According to [1], [2] more than one processor means multi-processors, while many-processors refers to big-n processors. The theoretical foundation for the two kinds of parallel machines is different and is meaningful for understanding the evolution of computer science in the emerging parallel computing era. While a multi-processor is a construct starting from Turing's model of computation, a manyprocessor is better explained in a different conceptual environment. We propose Kleene's model as a theoretical framework for describing the many-processor paradigm. In order to exemplify the many-processor approach the architecture of the BA1024 chip, a fully programmable SoC, is presented. Keywords: computer architecture, parallel computation, many-processor, partial recursive functions, integral parallel architecture U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 11 ISSN 1454-234x SHAPING SECURITY IN COMMUNICATION INFRASTRUCTURES WITHOUT RESTORING IN CASE OF MALFUNCTION Gheorghiţă PESCARU This paper is an attempt to analyze the likelihood of calculating an overall security coefficient for a given communication infrastructure that can be used in various communication services, such as e-healthcare, e-government, or other similar services. The assumption is that providing (certain) communication services for these types of applications is supposed to permanently allow configuration and reconfiguration of a communication network for variable time frames. But, under these circumstances, what can be said about the security of the resulting infrastructures mainly if certain security parametres are paramount and required beforehand? Keywords: security coefficient, communication services, security parameters FIREWALL POLICY MANAGEMENT USING SECURE WEB SYSTEM Daniel GHEORGHICĂ, Victor CROITORU In recent years firewalls have seen some impressive technological advances (e.g. stateful inspection, transparency, performance, etc.) and wide-spread deployment. In contrast, firewall and security management technology is lacking. In this paper we propose a secure web system for firewall policy management. Our secure system implementation is able to manage any firewall products that support SSH remote management. We believe that our approach is an important step towards streamlining the process of configuring and managing firewalls, especially in complex, multi-firewall installations. Keywords: firewall, security, management interface, GUI, PHP, UML U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x ASPECTS REGARDING NUMERICAL MODELING OF INDUCTIVE HEATING PROCESS FOR LOW VOLTAGE ELECTRICAL CABLES Costel PĂUN In this paper is presented an algorithm for numerical modeling of inductive heating process for low voltage electrical cables.The results will be used in studies of cables electrical isolation proprieties. It is possible to do a correlation between thermal effect on cables isolation, produced by electrical current witch goes over cable and lead to isolation damage.Using numerical simulation results, we can equalise inductive heating effect witch is a test with isolation heating effect in normal condition.The cable for study is of cylindrical section with PVC insulation Keywords: electrical cables, induction oven,numerical simulation, PVC insulation EVALUATION AND DESIGN OF A SHIELDING SCREEN Daniela CĂZĂNARU, Andrei SZILAGYI This paper describes a work covering some aspects of the electromagnetic compatibility (EMC) design optimization of a shield for a informatic equipment. Based on the presented simulations, the authors stress that the shielding structure has an own resonance frequency, the value of it is important to be known, in conjunction with the frequency of the signals existing and propagating into the electronic equipment shielded. Keywords: shielding, electromagnetic compatibility (EMC), TEMPEST EFFECTS OF IONIZING RADIATION ON THE DIELECTRIC PROPERTIES OF LDPE-AL2O3 NANOCOMPOSITES Florin CIUPRINA, Traian ZAHARESCU, Silviu JIPA, Ilona PLEŞA, Petru V. NOŢINGHER, Denis PANAITESCU The goal of this paper is to study the irradiation effects on the dielectric behaviour of a polymer nanocomposite dielectric made of low density polyethylene filled with nanoparticles of Al2O3. The permittivity and tan delta values were U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 13 ISSN 1454-234x determined by dielectric spectroscopy over a frequency range of 1 mHz – 10 MHz on plane samples of the tested nanodielectrics. The dependance between the filler concentration, between 2 and 10 wt.%, and the irradiation effects on the dielectric properties is also discussed in the paper. Keywords: dielectric properties, ionizing radiation, nanodielectrics DISCRETE RESISTIVE MODELS FOR MULTI-RATE ANALYSIS OF INTEGRATED ANALOG CIRCUITS Cǎtǎlina-Gabriela POPESCU For the nonlinear circuits with widely-separated time scales it is used the analysis in multi-time variables because the traditional analysis is very difficult. By applying this approach the differential algebraic equations describing the nonlinear analog circuits driven by multi-tone signals are transformed into multi-time partial differential equations. In order to solve these equations, associated discrete resistive equivalent circuits (companion models) for the dynamic circuit elements are used. This paper propose new companion models for multi-rate analysis of integrated analog circuits, generated by trapezoidal algorithm. Keywords: companion models, multiple time variables, trapezoidal algorithm, integrated circuits MODELING DYNAMIC HIGH INTENSITY DISCHARGE LAMP CHARACTERISTICS Florin Ciprian ARGATU, Costin CEPIŞCĂ This paper proposes a model curve-fitting approach for modeling HID lamps voltage–current characteristics based on measured lamp voltage and current. The lamp conductance is considered as a series of piecewise cubic polynomials that describes the nonlinear voltage-current characteristic of the lamp. The proposed model has been tested with a 70W high pressure sodium lamp. By comparing the measured and simulated results, it shows that the proposed model can accurately model the lamps for harmonic studies. Keywords: model, HID lamps, cubic spline interpolation, i-v characteristic U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 ISSN 1454-234x DISK-ROTOR SERVOMOTOR FED BY AN AC/DC CONVERTER Ana-Maria DUMITRESCU, Anca STAN, Dragoş DEACONU, Aurel CHIRILĂ, Valentin NĂVRĂPESCU, Mihaela ALBU, Gianfranco CHICCO In the paper the mathematical model of a disk-rotor servomotor is presented along with that of a AC/DC converter. The identification method used for the motor's electro-mechanical parameters is also presented. Finally, a comparison between the simulated data and experimental results along with an analysis of the converter-DRSM assembly influence over the supplying network is made. Keywords: numerical modeling, disk-rotor DC servomotor, fully controlled AC/DC converter ANALYSED TRANSIENTS DURING ISLANDING OPERATION OF ONE HPP ON ITS AUXILLIARIES Ioniţă DAESCU, Călin MUCICHESCU, Basarab GUZUN, Daniel MORAR The present work is aiming to study the significant dynamic behavior of one hydro power generator HG from one hydro electric power plant HPP, together with one electric motor ME from its internal network of auxiliaries, in the event of a sudden load rejection that follows one normal running regime into the powerful electric grid, to the islanding operation. There are investigated through the Simulink program, the main transients undergone by the assembly HG-ME. In this respect, it is focused one representative situation in which one HPP (rated 2 x 10MW) affected by its automatic regulators is connected – then separated from one regional part from our National Power Grid SEN, together with one local consumer (rated 2 MW) and one electric asynchronous motor (rated 7.5 kW), according to one typical lay-out electric diagram for the medium hydro power plants MHPP. Keywords: hydro power plant HPP, hydro generator HG, automatic regulators – speed governor, voltage regulator, electric asynchronous motor ME, electric power grid, islanding operation, Simulink , simulations U. P. B. Sci. Bull., Series C, Vol. 72, Iss. 3, 2010 15 ISSN 1454-234x A NOTE ON ROUGH SET THEORY APPLICATIONS IN POWER ENGINEERING Ioana PISICĂ Rough Set theory, proposed by Zdzislaw Pawlak in 1982, has proved to be an adequate technique in imperfect data analysis, which has found interesting extensions and various applications. It can be regarded as complementary to other theories that deal with imperfect knowledge, such as or fuzzy sets or Bayesian inference. The paper presents some Rough Set theory applications in electrical power engineering. Keywords: data management, information systems, knowledge engineering, power systems ETUDE EXPERIMENTALE DE LA GAZEIFICATION DES DECHETS DE BOIS Răzvan VÎJEU, Victor ATHANASOVICI This work is dedicated to the experimental study of wood waste gasification using a specially designed pilot staged gasifier. The drying/pyrolysis, partial oxidation and reduction stages are physically separated into distinct reactors. Temperature and gas composition measurements allow the correct characterization and attunement of process parameters for each reactor. Ces travaux sont dédiés à l’étude expérimentale de la gazéification des déchets de bois dans un gazogène pilote spécialement conçu ce projet. Les étages de séchage/pyrolyse, combustion partielle et réduction sont séparées physiquement dans des réacteurs distincts. Des mesures de température et de composition des gaz permettent de bien déterminer et régler les paramètres de fonctionnement des réacteurs. Mots-clés: bois, biomasse, gazéification