Arhivă — Seria C

1

NUMERICAL STABILITY OF ADAPTIVE CONTROL ALGORITHMS

Ciprian LUPU, Andreea UDREA, Dumitru POPESCU, Cãtãlin 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 includ…

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2

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 interroga…

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3

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 cond…

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4

PRODUCTION SCHEDULING IN A HOLONIC MANUFACTURING SYSTEM USING THE OPEN-CONTROL CONCEPT

Silviu RÃILEANU

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 …

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5

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 mec…

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6

LOW DISTORTION AND ROBUST STEGANOGRAPHY ON PARALLEL ARCHITECTURE CELL BE USING A SHARED COLOR PALETTE AND A SHARED HASH

Bogdan ÞIGÃNOAIA, 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 syst…

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7

CELLULAR AUTOMATA WITH DYNAMICAL LOOP FUNCTION AS NOISE GENERATORS: STATISTICAL ASPECTS (1)

Ioan HÃLÃLAE

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. \r\nFor the definition of randomness we adjusted the one used in the algorithmic information theory for binary …

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8

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 specif…

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9

SPATIAL DATA ACQUISITION, MANAGEMENT AND VISUALIZATION IN GEOGRAPHIC INFORMATION SYSTEMS

Liliana DOBRICÃ, Traian IONESCU, Leonard DOBRICÃ, 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…

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10

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 elli…

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11

FPGA IMPLEMENTATION OF VIDEO PROCESSING-BASED ALGORITHM FOR OBJECT TRACKING

Dan POPESCU, Dinu PÃTÂRNICHE

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 trac…

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12

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 syst…

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13

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…

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14

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++ Pr…

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15

FUZZY CONTROL OF AUTONOMOUS MOBILE ROBOT

Olumide OBE, Ioan DUMITRACHE

Seamless navigation of autonomous mobile robots in an unstructured, non-episodic 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 m…

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16

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 s…

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17

MANY-PROCESSORS & KLEENE’S MODEL

Mihaela MALIÞA, Gheorghe M. ªTEFAN

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 mul…

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18

SHAPING SECURITY IN COMMUNICATION INFRASTRUCTURES WITHOUT RESTORING IN CASE OF MALFUNCTION

Gheorghiþã 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 …

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19

FIREWALL POLICY MANAGEMENT USING SECURE WEB SYSTEM

Daniel GHEORGHICÃ, 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.\r\nOur secu…

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20

ASPECTS REGARDING NUMERICAL MODELING OF INDUCTIVE HEATING PROCESS FOR LOW VOLTAGE ELECTRICAL CABLES

Costel PÃUN

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 witc…

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21

EVALUATION AND DESIGN OF A SHIELDING SCREEN

Daniela CÃZÃNARU, 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 conjun…

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22

EFFECTS OF IONIZING RADIATION ON THE DIELECTRIC PROPERTIES OF LDPE-AL2O3 NANOCOMPOSITES

Florin CIUPRINA, Traian ZAHARESCU, Silviu JIPA, Ilona PLEªA, Petru V. NOÞINGHER, 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 determined by dielectric spectroscopy over a frequency range of 1 mHz – 10 MHz on p…

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23

DISCRETE RESISTIVE MODELS FOR MULTI-RATE ANALYSIS OF INTEGRATED ANALOG CIRCUITS

Catalina-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 mult…

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24

MODELING DYNAMIC HIGH INTENSITY DISCHARGE LAMP CHARACTERISTICS

Florin Ciprian ARGATU, Costin CEPIªCÃ

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 …

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25

DISK-ROTOR SERVOMOTOR FED BY AN AC/DC CONVERTER

Ana-Maria DUMITRESCU, Anca STAN, Dragoº DEACONU, Aurel CHIRILÃ, Valentin NÃVRÃPESCU, 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…

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26

ANALYSED TRANSIENTS DURING ISLANDING OPERATION OF ONE HPP ON ITS AUXILLIARIES

Ioniþã DAESCU, Cãlin 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 ele…

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27

A NOTE ON ROUGH SET THEORY APPLICATIONS IN POWER ENGINEERING

Ioana PISICÃ

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…

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28

ETUDE EXPERIMENTALE DE LA GAZEIFICATION DES DECHETS DE BOIS

Rãzvan 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 …

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