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Electronics Technology: Meeting the Challenges of Electronics Technology Progress, 2004. 27th International Spring Seminar on

Date 13-16 May 2004

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Displaying Results 1 - 25 of 56
  • Formal models for system design (challenges on exchanges in the main role between hardware and software going to the systems packaging)

    Page(s): 564 - 568 vol.3
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    This paper envisages main trends in systems design. Observation over and comparison between paradigms in software and hardware design is presented. Finally the paper focuses on three of most popular and important hardware design languages VHDL, SDL and SystemC. A special stress is done on how do they work outside hardware design and how they do package software and hardware in one device. View full abstract»

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  • New technology for recording the information based on intramolecular bonds in water

    Page(s): 569 - 573 vol.3
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    A new technology for recording information based on the discreet spectrum of the intramolecular bond energies in water is described. For the latter the existence of a space net of bonded with H-bonds molecules with approximate tetrahedral symmetry is supposed. The discrete character of the water energy spectrum is proved by the measurement of the surface tension variations of evaporating water drops. Using the Shannon's formula, a new term information spectrum of water is introduced, in which the information related to one pair of water molecules as a function of the discrete values of the intramolecular bond energies is represented. The experimental results showing why this information spectrum as a method registered the weak physical and chemical influences on the water are represented. View full abstract»

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  • Economic environment in Bulgaria for small enterprises in the electronics production sector

    Page(s): 552 - 553 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (113 KB) |  | HTML iconHTML  

    This paper addresses the question of whether the economic environment for SMSEE (small and medium size enterprises) in Bulgaria can be described as "legislative hysteria and triumph of the bureaucrat". The paper focuses on certain economic and legislative problems for small manufacturing enterprises with elements of engineering high-tech in the electronic production sector. View full abstract»

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  • Remote sensing of position and acceleration

    Page(s): 413 - 416 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (208 KB) |  | HTML iconHTML  

    Acceleration and position transducers are one of the most widely used sensors for monitoring civil engineering structures, mechanical devices, industrial process systems and even biomedical systems. One of the main issue in designing instrumentation with such sensors is the ability of remote interaction in order to reduce as much is possible any interference with the measured physical value. This statement usually implies the use of low power embedded systems for acceleration and position sensing and wireless data transfer for acquiring relevant readings. This paper proposes a low power embedded sensing system for acceleration and position based on a common capacitive transducer. The system integrates in one single chip the signal conditioning blocks (for the transducers), the analog-to-digital converter and a fast infrared communication module for data transmission. The proposed solution increases the possibility of integrating arrays of such low-cost sensors in remote sensing network systems for acceleration and position, allowing an increased accuracy and performance for all interested domains of application. View full abstract»

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  • Influence of information technology on military radar systems

    Page(s): 557 - 563 vol.3
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    The paper discusses influence of information technology (IT) on military radar systems and how this impacts upon conducting military operations. Applications of new technologies in three basic areas of military radar systems are considered: surveillance and automatic target recognition systems; tracking systems and data and signal processing. Some possible uses of radar data are shown along with how this will improve the efficacy of planning, coordinating, directing and controlling of military actions. View full abstract»

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  • Biopotential measurement system for neurophysiology

    Page(s): 410 - 412 vol.3
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    The paper presents an inexpensive and very useful system for biopotential measurements. The system consists of a simple electrical circuit and a set of well-adjusted programming modules. It has been developed for practical application in hospitals. This system is a part of project for the development of the inexpensive technical devices for Bulgarian physicians. View full abstract»

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  • Nanoscale materials - production, properties and applications

    Page(s): 540 - 542 vol.3
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    A well known method for the preparation of nanomaterials is the chemical reduction of metal ions, dissolved in water, with an aqueous solution of an alkali metal borohydride as the reduction agent. This method has been used to produce various compositions of nanoparticles, nanowires, nanoscale hydrogen containers, etc. The knowledge and the comparison of date for the bond strength of various diatomic molecules help us to choose proper combinations of elements in order to synthesize nano-systems with pre-requested properties. View full abstract»

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  • Electronic packing for control and management of air traffic

    Page(s): 574 - 576 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (192 KB) |  | HTML iconHTML  

    The paper describes results from research and development of the system for integration of civil and military flight data plans. This system is designed for the Air Sovereignty Operational Center of Bulgaria. In the paper the aim and main tasks of the system are described. The structural diagram of the system is presented. It is proposed were to place its peripheral and central modules at the territory of Bulgaria. The laboratory model of the system is developed. The preliminary tests are successful. View full abstract»

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  • Device for visualization of information from linear optical sensor

    Page(s): 421 - 423 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (120 KB) |  | HTML iconHTML  

    In engineering practice, over and over again, there is an increase in the area of applications based on linear and matrix array optical sensors which are sensitive to EM radiation and produce electrical signals in proportion to the radiation strength. Constructing a visualization of the received sensor data on a visual terminal-monitor is essential from the viewpoint of testing the efficiency and providing an optimal working mode of the sensor, such as setting up an integration time, and adjusting the optical system by monitoring of the digital output level of all pixels. The resources for control sensors which process the collected information are different and depend on the particular problem requiring solution. The fast growth of programmable logic naturally leads to sources for achieving a solution - these are XILINX's programmable logic devices. In addition, the versatile high hierarchy language VHDL for describing, simulating, synthesizing and implementing of digital sockets directs the final choice. View full abstract»

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  • A high power high frequency laser diodes driver

    Page(s): 451 - 452 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (129 KB) |  | HTML iconHTML  

    Summary form only given. A new high power laser diode driver has been developed and tested. The possibilities for driving high power laser diode bars and stacks at high frequencies has been shown. The driver is with 0.5% noise and ripple at DC, and can be modulated with 15 ns rise/fall times at 100 A, with maximum frequency for square wave modulation up to 5 MHz. The spikes for the optical output at switching on/off do not exceed 5%. The limitation of the used scheme allows frequencies up to 30 MHz and currents to 400 A to be reached. The driver opens new applications with laser diodes with more than 100 W CW output power. This output power means free space communication at 20 Mbit/s over hundreds of kilometres, the possibility for a 3D range finder with 15 km distance (without a retro prism) and 1 cm distance accuracy, new possibilities for micro machining, synchro pumping solid state lasers or other semiconductor lasers, etc. View full abstract»

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  • Implementation and evaluation of an e-learning architecture based on MSClass Server

    Page(s): 506 - 509 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (189 KB) |  | HTML iconHTML  

    In this paper, we present the design, implementation and evaluation of an e-learning architecture with integrated Microsoft Class Server technology. The accent is put on the architecture, defined in the paper as "adaptive mechanisms in learning technology architecture based on MS Class Server". The ongoing evaluation process, taking place with 120 2nd year full-time students has been described. The pilot discipline, used to evaluate the architecture, is "electronic circuits theory", part of the main curricula in the Department of Electronics at the Technical University of Sofia. View full abstract»

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  • An adaptive approach for linearization of temperature sensor characteristics

    Page(s): 417 - 420 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (225 KB) |  | HTML iconHTML  

    This paper discusses an adaptive approach, based on iterative construction of a piecewise linear approximant, for calibration of industrial sensors. Given the non-linear characteristics of the sensor, the approach consists of two steps: (i) the inverted characteristic is computed in pointwise form on the basis of an iterative Newton-Raphson scheme; (ii) an iterative algorithm is employed in order to construct a continuously improving set of piecewise linear approximations of the computationally inverted sensor characteristic. The main feature of the presented approach is the irregular partitioning of the measurement range, induced from the error minimization procedure performed in (ii). On this basis, the lookup table necessary for calibration of the sensor is constructed in the "cheapest" possible way, allowing on the one hand optimal linear approximation in every particular measurement sub-range and on the other an effective reduction of the necessary storage capacity. View full abstract»

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  • Method for analysis of lossy transmission lines

    Page(s): 439 - 443 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (240 KB) |  | HTML iconHTML  

    The paper presents a new method for transient analysis of lossy transmission lines that have nonlinear circuits as termination. To achieve this purpose, modal decomposition in the frequency domain was used as well as matching of rational function approximations to the frequency dependent eigenvalues, eigenvectors and admittance matrices. Rational function approximation eliminates the need to use the fast Fourier transform (FFT) or numerical inversion of the Laplace transform (NILT) and, secondly, this type of approximation allows an efficient evaluation of the convolution integral in the time domain. A practical example is also presented to demonstrate the accuracy of the simulation method. View full abstract»

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  • Extended differential long-term predictive universal coding

    Page(s): 476 - 480 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (204 KB) |  | HTML iconHTML  

    In this paper, we propose an extended differential pulse code modulation (DPCM) method for sources with unknown parameters (of any theoretical class). The main features of the method are long-term prediction and backward adaptation by forward analysis with a dynamically adjustable prediction precision criterion. The predictors of the encoder and the decoder are synchronized by commands via a logical pipe. The proposed structures can be implemented thoroughly in hardware. View full abstract»

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  • Stability analysis of digital radio channels under the influence of the signal inter-symbolic interference

    Page(s): 383 - 387 vol.3
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    Inter-symbolic interference is analyzed as a disturbance. At a given information flow and known pulse characteristics of the channel, the received signal could be defined with precision up to the additive disturbance. A mathematical model of a radio channel with frequency-dependent parameters received under inter-symbolic interference is proposed. This method for compensation of inter-symbolic interference allows evaluation of the error probability during the process of received signal recognition for different types of signal modulation and proposes algorithms for inter-symbolic interference compensation. View full abstract»

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  • Short-time trends in market development of information communication technologies (ICT) and Bulgaria's place in it

    Page(s): 547 - 551 vol.3
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    Using analysis of the information communication technologies market in a short time period, the authors have observed the market developments during the last 10 years of the 20th century. They show market differentiation based on the type of sector (private and public) and also four levels of segmentation - services, software, hardware and total status. View full abstract»

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  • Design of electronic hardware using VHDL described with the example of baseband and LMP layers in Bluetooth

    Page(s): 453 - 456 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (383 KB) |  | HTML iconHTML  

    Each network device or portable device with HOST interface (radio or cable) has several hierarchical structures which distribute functionality between different layers of that device. Bluetooth is a radio interface which support this architecture. There are five mandatory layers of hierarchy defined: radio interface; baseband layer; link manager protocol (LMP) layer; logical link control and adaptation protocol (L2CAP) layer; HOST user interface. The paper describes the design of the digital baseband and LMP layers from the hardware development aspect of network algorithms. The baseband layer performs the functions related to interface interaction between the Bluetooth chipset and an external or integrated radio chip and a host system. In baseband, different modules for data processing are integrated, like modules for generating frequency hopping sequences, fast error correction codes, cyclic redundancy check algorithm, whitening, data packet assembling and de-assembling. In addition, some hardware optimizations have been made to meet the requirements of modern electronics. By reason of a higher degree of design abstraction, the development of the module has been done with hardware description language $VHDL. During development of the Bluetooth module, a new complex architecture is integrated; it supports low cost upgrades related to new generations of Bluetooth devices. The design has been provided with a generic microprocessor interface for easy adaptation in the Bluetooth system. View full abstract»

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  • Automated system for selecting optimal technological variant and design of passive elements in hybrid micro modules

    Page(s): 535 - 539 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (324 KB) |  | HTML iconHTML  

    A program module for selection of an optimal technological variant during design of hybrid micro modules has been developed. It allows the opportunity to solve the optimization problem based on the available technology materials, elements and scheme. The selection of the combination of weight coefficients that describe the efficiency of the result and visualization of the hybrid micro modules (HMM) facilitates the attainment of an optimum technological variant during the design phase. The results are compatible with Cadence by means of exporting the script file. View full abstract»

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  • Technical requirements in enterprise resource planning systems

    Page(s): 461 - 466 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (346 KB) |  | HTML iconHTML  

    An enterprise resource planning (ERP) system is defined as a unified information system, performing all information-processing tasks of a company and realizing an integration of the whole corporation. The aimed scope of duties indicates that these software products are very complex regarding their structure and operation. What is more, ERP systems are almost always standard software products. The parametrizable and configurable structure increases their complexity. We analyse these complex software products. We examine the users' needs and the life-cycle of these systems, determine their components according to the three tier architecture and summarize the requirements against these parts. View full abstract»

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  • Modern education methods in extracting power factor preregulator's parameters

    Page(s): 393 - 397 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (180 KB) |  | HTML iconHTML  

    The modern design of switch-mode power supplies is mainly targeted on designing the power factor correction (PFC) circuitry, since most of the engineering effort is oriented towards power quality issues. As a result, teaching power supply design is more and more related to power factor correction instead of harmonic suppression and EMC filters. Thus, the main issue in designing power factor circuits resides in proper selection of components and control techniques for various topologies of switch mode power supplies. The paper proposes a new method of interactive training in power factor circuits by implementing a power factor control model for simulating various scenarios on a boost converter for both continuous and discontinuous modes of conduction. The simulation model is designed in MATLAB/SIMULINK in order to increase the possibility of further development and to allow integration in other educational platforms. The proposed power factor model also allows a better and more accurate simulation for switch mode power supplies along with the related educational benefits of using a widely known simulation environment (MATLAB/SIMULINK). View full abstract»

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  • System for test and verification of the thermostat from automobile cooling system

    Page(s): 424 - 428 vol.3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (347 KB) |  | HTML iconHTML  

    This paper presents a PC-based system for test and verification of the thermostat from an automobile cooling system. The application measures the displacement of the thermostat valve as a function of temperature. Measurement data are plotted and then stored in a file. The application was developed in LabVIEW, the most commonly used graphical language for virtual instrumentation. For measurement and data acquisition, a module from the I-7000 series, made by ICPDAS, was used which has great performance and is very easily to use. By combining the performance of these modules with the great flexibility and stability of the LabVIEW programming language, a measurement system can be designed that assures very good accuracy, stability and reliability, with low cost. View full abstract»

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  • Polymer microwave absorber with nanosized ferrite and carbon fillers

    Page(s): 577 - 579 vol.3
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    The paper presents studies on the microwave properties of two types of polymer composites based on acrylic resin and polyurethane with nanosized magnetic (magnetite) and dielectric (carbon) fillers. The microwave (MW) absorption was measured at 9.4 GHz, while the dielectric and magnetic properties were investigated in the frequency range 1-18 GHz. Promising MW absorption properties were observed for nanostructured filler applications in comparison with the traditional MW absorbers. View full abstract»

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  • Models Of Technology And Change In Higher Education

    Page(s): 500 - 505
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