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Proceedings of the Technical university of Sofia, 1995 -: Recent submissions

Now showing items 761-780 of 853

Title: Структурно – лингвистичен подход за анализ на тримерно визуални сцени Author: Гочев, Гочо Вълев; Gochev, Gocho Valev Date: 2003 Abstract: Innovative method and algorithm for analysis and decomposition of three dimensional (3D) visual scenes is considered in the paper. The method is based on the topology of the vertices (topological features) of the three dimensional bodies. The biggest weights are assigned to the features located on the border contours with the background. ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Моделиране на данните в корпоративни бази от данни за дискретното производство Author: Tsankova, Rumyana Strashimirova Date: 2003 Abstract: The objects in the discrete production have a complicated structure with hierarchy, network and recursive elements and its corporative management needs progressive information technologies as multidimensional analysis (OLAP), information aggregation and synthesis. New and suitable for the structure and functionality of the discrete production ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Expert evaluation of a river network pollution based on a structural – linguistic model Author: Angelova, Maryja; Ангелова, Мария Date: 2003 Abstract: On the base of a structural-linguistic model of a river network a point pollution detection expert system is developed and a suggestion for the possible polluting objects is made. The final result of the expert system analysis is an arranged list of polluting objects with the highest score for the most probable of them. The structural model ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Спектрален анализ по метода на вълничките при разпознаване на говор Author: Момчеджиков, Михаил Благоев; Momchedzhikov, Mihailo lagoev; Попов, Румен Н.; Popov, Rumen N. Date: 2003 Abstract: In this paper are reviewed the disadvantages of currently most ed methods for spectral analysis in Speech Recognition — bank of filters, ear Predictive Coding and Fast Fourier Transform. Also, Frequency Warped st Fourier Transform is analysed and a new method, based on Wavelet nsform, is proposed, which surmounts to a great extent these disadvantages. Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Симулиране на мъртва хватка Author: Николов, Лилян Илиев; Nikolov, Lilyan Iliev Date: 2003 Abstract: This paper discusses the problem of deadlock avoidance in the operating systems. A package of programs for simulating the possibility of deadlock occurences in different states of the system and the deadlock avoidance during the resources allocation is presented. The program offers an user interface in the form of windowses and menus. Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Сравнителен стохастичен анализ на паралелни процеси в матрични структури Author: Романски, Ради Петров; Romanski, Radi Petrov Date: 2003 Abstract: The paper presents an investigation of two different process models for parallel computations, applicable to N-size matrix structures. A comparative analysis of systolic (synchronous) and dataflow (asynchronous) computations is made to determine some important characteristics (computation efficiency, communication loss of time, process ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Distance learning system of low frequency magnetic field and beatdown problem Author: Hristov, Valentin P.; Dimitrov, Dimitаr Ts.; Христов, Валентин П.; Димитров, Димитър Ц. Date: 2003 Abstract: In the present article is presented a distance learning system "3D Computer model of low ferdenced magnetic field (medical images)" and beatdown problem. The aim of this paper is to propose an approach to overcome this problem through improving ATM mechanism to early packet discarding and evaluate the its fairness. Using simulation model ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Distance analysis of EKG Author: Dimitrov, Dimitаr C.; Велчев, Юлиян; Velchev, Yuliyan; Dimitrov, Dimitаr Tsv.; Димитров, Димитър Цв. Date: 2003 Abstract: 24 — hour registering of the human heart activity is a well known in medical diagnostics. This is a very effective tool in the cardiology, on the base of application of Hotter - a portable device used for g of the electorocardiogram (ECG). Often it is necessary to record only 'cal events in the ECG signal. In this case the digital Holter ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Gain– and offset – compensated two-phase switched-capacitor integrators based on the second – order Adams-Bashworth’s integration method Author: Radev, Nikolay Asenov Date: 2003 Abstract: Two gain- and offset- compensated two-phase switched-;apacitor integrators based on the second-order Adams-Bashworth's ntegration method are presented. Analytical expressions for the gain, phase ind offset voltage errors are derived and compared with the corresponding errors of the earlier ones uncompensated integrators. The effectiveness ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Проектиране на нисковолтов CMOS операционен усилвател на проводимост Author: Манолов, Емил Димитров; Manolov, Emil Dimitrov Date: 2003 Abstract: In this paper the circuit of single stage low-voltage CMOS -rat transconductance amplifier (OTA) with rail-to-rail input range is i and procedure for its dimensioning is proposed. The obtained results are successfully in the design of operational transconductance amplifier with oltages ±1.5 V and input common mode range ±1.5 V. Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Възможности за измерване на ъглова скорост на проводящи среди с вихровотоков преобразувател с ъглово отместени намотки Author: Гунински, Стефчо Георгиев; Guninski, Stefcho Georgiev Date: 2003 Abstract: In the paper output signal of transformer eddy current transducer with angle displaced excitation and receiver coils located above conductive ferromagnetic cylindrical object is analyzed. The voltage plane diagrams of the voltage in the receiver coil and the dependences of its components on the angular velocity are drawn at different ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Математически модел за газоразрядни лампи с високо налягане при димиране Author: Рац, Нели Симеонова; Rats, Neli Simeonova Date: 2003 Abstract: The article presents a mathematical model which reflects the dependence of the electric current, the voltage of the arc and the luminous flux at different lighting intensity of discharge lamps. Variable coefficients of differential equation are deduced for the dinamic regime. On this basis analitical dependence is offered for the luminous ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Нелинеен математичен модел на електромеханичните преходни процеси в еднофазен колекторен двигател, базиран на метода на крайните елементи : I част – постоянен ток Author: Божилов, Ганчо Йорданов; Михов, Михо П.; Иванов, Адриан П.; Bozhilov, Gancho Yordanon; Mihov, Miho P.; Ivanov, Adrian P. Date: 2003 Abstract: A mathematic model of the electromechanical transients in single-phase commutator motor is developed which take into consideration non-linear variation of the winding inductances and magnetic flux as they depend by armature current. The influence of the armature winding reaction is take into account as for the computing of the magnetic ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Замяна на графичното построение на характеристиките на постояннотокови двигатели с аналитично изчисление Author: Божилов, Ганчо Йорданов; Стипцов, Владимир В.; Михов, Михо П.; Bozhilov, Gancho Yordanov; Stiptsov, Vladimir V.; Mihov, Miho V. Date: 2003 Abstract: In this paper an algorithm is offered for analytical calculation of characteristics of direct-current series and compound motors. Corelations have been developed allowing analythical calculation of the curves which offers possibility for their easy obtaining and visualization, as any manual drawing and calculations are obviated. The algorithm ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Основни принципи при изграждане на САУ [Система за автоматично управление] на топлинното натоварване на блокове 210MW за лигнитни въглища Author: Тотев, Тотьо Иванов; Totev, Totyo Ivanov Date: 2003 Abstract: The desire of Bulgaria for association with the European economic structures is connected to putting and solving special questions, which are related to our power generation system. One of these requirements is the maneuverability of the units 210 MW, using low-rank lignite coal of the basin "Maritza lztok". At this stage, the satisfaction ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Управление на куполометър за изследване на вестибуларния апарат Author: Бакърджиев, Димитър Христов; Angov, G.; Ангов, Г.; Zhilevska, M.; Жилевска, М.; Bakardzhiev, Dimitar Hristov; Бакърджиев, Христо; Bakardzhiev, Hristo Date: 2004 Abstract: The risks of vestibularis illnesses increase with transport development. The early diagnostics is of great importance to the successful treatment. There is a suggestion for a cupulometre for vestibularis research. By that with very high level of precision speed and acceleration range is determinated and controled.So the researches become ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Ултразвукови сензори за откриване на обекти в работната среда на сервизни роботи Author: Георгиев, Георги Иванов; Georgiev, Georgi Ivanov Date: 2004 Abstract: The progress of modern service robots is definitely based on the advance of the information system, indispensable for the adaptive behavior of the robot to the changeable condition during the work. It includes sensor devices and information channels for registration and analyses of the working environment state. In the article we examine ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Анализ на два съвременни метода за измерване на частични разряди Author: Барутчийски, Светослав Гошев; Barutchiyski, Svetoslav Goshev Date: 2004 Abstract: In this article are presented two methods for measurement of partial discharges (PD). The first one has been based on fiber optic Fabry-Perot sensor for measurement of PD in power transformers. That interferometer is suitable for accurately measurement of acoustic signals in transformer's oil and posses a high sensitivity and wide broadband ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Електрическо поле в кабелна муфа за едножилен кабел за средно напрежение със синтетична изолация Author: Червенков, Атанас Георгиев; Chervenkov, Atanas Georgiev; Петков, Стоян Лазаров; Petkov, Stoyan Lazarov; Тодорова, Антоанета Константинова; Todorova, Antoaneta Konstantinova Date: 2004 Abstract: The suitable system of cable muff for trial of power cable at time varying voltage in laboratory conditions is considered. The cable muff must ensure linear distribution of electrical strength in the end of cable. The stationary electrical field in the cable muff by finite element method is investigated. The distribution of electrical ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: On the sliding mode control of DC/DC converters Author: Trushev, Ivan Mitkov; Mladenov, Valeri Markov; Трушев, Иван Митков; Младенов, Валери Марков Date: 2004 Abstract: Based on the sliding mode control (SMC) principle [8] a controller of a pulse-width modulated (pw.vo buck DC/DC converter is considered. Modeling and simulations of the behavior of the system is very important before the on chip realization. The converter has been simulated in PSpice and Simulink and its dynamic performances have been shown ... Library:
TECHNICAL UNIVERSITY - SOFIA