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

Now showing items 421-440 of 853

Title: Симулационно моделиране на пещните процеси на котел ПК-38-4 в ТЕЦ „Марица Изток 2” Author: Тотев, Тотьо Иванов; Бонев, Бончо Иванов; Попова, Виктория Д.; Станков, Никола рец.; Totev, Totyo Ivanov; Bonev, Boncho Ivanov; Popova, Viktoriya D.; Stankov, Nikola rew. Date: 2005 Abstract: Now, as a result of the long-time operation, as well as some constructive peculiarities of the boilers type PK-38-4, they don’t respond of the increased requirements for the steam output, reliable, effective and ecological work. Natural first step of the task for rehabilitation of the powers is “investigation of their work and estimation ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Използване на гаусови модели за отделяне на изображенията на човешки лица Author: Бумбаров, Огнян; Василева, Диана; Bumbarov, Ognyan; Vasileva, Diana; Момчеджиков, Михаил Благоев рец.; Momchedzhikov, Mihail Blagoev rew. Date: 2005 Abstract: This paper is concentrated on skin color based modeling. Gaussian single model (GSM) and Gaussian mixture model (GMM) are presented. Three variety interpretations of Gaussian function are implemented and compared each other. YCbCr is used like luminance and chrominance components separate color space. The stress in the paper is on Gaussian(s) ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Разпознаване на изображенията на лица с използване на анализ по главни компоненти Author: Бумбаров, Огнян; Bumbarov, Ognyan; Соколов, Страхил; Sokolov, Strahil; Момчеджиков, Михаил Благоев рец.; Momchedzhikov, Mihail Blagoev rew. Date: 2005 Abstract: A face recognition algorithm is presented – for fontal face images. It is based on skin color detection and principal component analysis. Our algorithm includes: face detection based on human skin modeling, Principal Component Analysis (PCA) and classification. PCA is a statistical technique for dimensionality reduction of data. PCA on a ... Library:
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Title: Алгоритъм за aнализ на клас сигнали Author: Манев, Стойчо В.; Manev, Stoycho V.; Георгиев, Владимир Ив.; Georgiev, Vladimir Iv.; Илиев, Илия Date: 2005 Abstract: The basic algorithms for analysis of class of signals have been presented and comparison has been made. A modified algorithm for analysis of class of signals has been proposed. The effectiveness of the algorithm, designed to process different types of determined signals, has been shown. Тhe Lyapunov’s exponents are find and some respective ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Невронна мрежа за търсене в celp кодовата книга чрез оценка на линейните спектрални двойки (LSP) Author: Плешкова, Снежана Георгиева; Pleshkova, Snezhana Georgieva; Момчеджиков, Михаил Благоев рец.; Momchedzhikov, Mihail Blagoev rew. Date: 2005 Abstract: The search process in CELP code book is a sequence of error estimation of each code book vector, if this candidate-vector is used in vector quantization of original speech signal. The result of this sequence process is the choice of a code book vector, for which the book search is the most time consuming operation in CELP coding. Therefore, ... Library:
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Title: Метод за сравнителна оценка на celp декодираните говорни сигнали чрез линейни спектрални двойки LSP Author: Плешкова, Снежана Георгиева; Pleshkova, Snezhana Georgieva; Момчеджиков, Михаил Благоев рец.; Momchedzhikov, Mihail Blagoev rew. Date: 2005 Abstract: The linear spectral pairs (LSP) are sending in CELP speech coding systems as information of linear prediction model of speech signals. These coefficients have some specific properties: the ability of sending minimal numbers of bits, monotonic values increasing etc. In this article it is proposed to use the linear spectral pairs in other ... Library:
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Title: Микрофонни решетки с електронно управление на диаграмата Author: Момчеджиков, Михаил Благоев; Войчев, Стефан Върбанов Date: 2005 Abstract: In the article a method for electronic control of beamforming by microphone arrays on the base of properties and applications is described. There are presented experimental results by using elementary microphone arrays with two microphones which realize Griffits-Jimm diagram. The first experiment demonstrates beamforming and the second one ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: General approach for fast image retrieval from image databases using consecutive iterations in the transform domain Author: Кунчев, Румен Кирилов; Kunchev, Rumen Kirilov; Манолова, Агата Христова; Manolova, Agata Hristova; Момчеджиков, Михаил Благоев рец.; Momchedzhikov, Mihailo Blagoev rew. Date: 2005 Abstract: One of the most important problems connected with the organization of fast access to individual images in the database is related to the creation of effective algorithms for fast content based image retrieval. The research aims of this scientific work include the creation of a new general approach for fast image retrieval from multimedia ... Library:
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Title: Един подход при редуциране на шумове в ултразвукови медицински изображения Author: Кунчев, Румен Кирилов; Kunchev, Rumen Kirilov; Георгиева, Веска М.; Georgieva, Veska G.; Момчеджиков, Михаил Благоев рец.; Momchedzhikov, Mihail Blagoev rew. Date: 2005 Abstract: In the paper was presented an approach for specific noise reduction in medical ultrasound images on the base of 2D Wavelet Packet Transformations. An analysis of their properties was made and an effective algorithm was treatment. Some parameters of the wavelet transformations are optimized with the goal to become maximal noise reduction and ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Нелинейни ефекти при аналого-цифрово преобразуване на широкоспектърни сигнали Author: Илиев, Вася Б.; Момчеджиков, Михаил Благоев; Iliev, Vasya B.; Momchedzhikov, Mihail Blagoev; Кунчев, Румен Кирилов рец.; Kunchev, Rumen Kirilov rew. Date: 2005 Abstract: This article analyzes the nonlinear effects generated in analog to digital processing of spread spectrum noise like signals. The spectral components are determinated in the analog to digital convertor’s output using the Rise method. Mathematical expressions represent the signals, harmonic and intermodulation components in the quantization ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Инвариантни методи за обработка на сложни сигнали Author: Илиев, Вася Б.; Iliev, Vasya B.; Момчеджиков, Михаил Благоев; Momchedzhikov, Mihail Blagoev; Кунчев, Румен Кирилов рец.; Kunchev, Rumen Kirilov rew. Date: 2005 Abstract: This article describes some methods for correlation processing of complicated noise like signals, independent of the frequency and time delay of the received signals. The suggested methods are based on the fast transformation algorithms, which make them suitable for real time large base complicated signals processing. Library:
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Title: Въздействия върху скоростта на детонацията на вълновода на неелектрически системи за взривяване Author: Станчев, Георги Ст.; Stanchev, Georgi St.; Ангелов, Ясен; Angelov, Yasen; Арнаудов, Румен Кирилов рец.; Arnaudov, Rumen Kirilov rew. Date: 2005 Abstract: A comparatively research of the influence of mechanical loadings and climatic impacts on the detonation velocity of shock tubes produced by four different producers – two Bulgarian and two European leading firms is no electric detonators, is made in this paper. The shock tubes are put under the impact of hydrostatic pressure, high and low ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Методи за определяне влиянието на механични натоварвания и климатични въздействия върху скоростта на детонацията на вълновода на неелектрически системи за взривяване Author: Станчев, Георги Ст.; Stanchev, Georgi St.; Арнаудов, Румен Кирилов рец.; Arnaudov, Rumen Kirilov rew. Date: 2005 Abstract: A method for determination the influence of mechanical loadings and climatic impacts on the shock tube detonation velocity of no electric detonators is developed in this paper. This method is conformable to European and Bulgarian technical legislation. It develops completely European standards adopted in Bulgarian legislation and establishes ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Транскодиране на стереосигнал в 5.1 пространствен звук Author: Момчеджиков, Михаил Благоев; Momchedzhikov, Mihail Blagoev; Йорданов, Николай Руменов; Yordanov, Nikolay Rumenov; Кунчев, Румен Кирилов рец.; Kunchev, Rumen Kirilov rew. Date: 2005 Abstract: The recording in 5.1 surround sound is difficult and expensive process. The idea is that is much easier to create normal stereo mix and then expand it to 5.1 surround sound. In the next material the authors are described few ways for expanding stereo signal to 5.1 surround sound. Special program is made to give the user the flexibility to ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Изследване на ефективността на аудио кодеците по отношение на качеството на речта при различни условия на пакетните загуби Author: Генчев, Ивайло С.; Genchev, Ivaylo S.; Кунчев, Румен Кирилов рец.; Kunchev, Rumen Kirilov rew.; Момчеджиков, Михаил Благоев; Momchedzhikov, Mihailo Blagoev Date: 2005 Abstract: When transmitting real-time audio information through packet-switched networks, some packets are lost and this reflects directly on the perceived speech quality of the reproduced signal. Various codecs can be used and the perceived quality varies in a complex manner depending on the codec as well as statistical parameters of packet loss. ... Library:
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Title: Method for audio watermarking based on spectrum pyramid Author: Kunchev, Rumen Kirilov; Кунчев, Румен Кирилов; Todorov, Vladimir; Тодоров, Владимир; Kuncheva, Rumyana; Momchedzhikov, Mihail Blagoev rew.; Момчеджиков, Михаил Благоев рец. Date: 2005 Abstract: A new method for audio watermarking in the phase-frequency domain is presented, based on the Spectrum Pyramid, obtained using the Complex Hadamard Transform. The main advantages of the method are the absence of quantization noise, the lower computational complexity and the ability for the audio contents owner and for the authorized ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Lossless compression of graphics and contour images, based on WHT and ARLC Author: Kunchev, Rumen Kirilov; Кунчев, Румен Кирилов; Todorov, Vladimir; Kuncheva, Rumyana; Кунчева, Румяна; Тодоров, Владимир; Момчеджиков, Михаил Благоев рец.; Momchedzhikov, Mihailo Blagoev rew. Date: 2005 Abstract: In the paper is presented new algorithm for lossless compression of graphic and tour still images, processed with two-dimensional (2D) Walsh-Hadamard Transform and adaptive run-length coding (ARLC). The results obtained after processing of large number of test ages are presented in the paper and are compared with those for JPEG2000 standard. ... Library:
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Title: Изследване и разработка на технологии за създаване на тематични карти за приложение в интелигентни системи за обучение Author: Димитрова, Тодорка С.; Dimitrova, Todorka S.; Павлова, Райна Стоичкова; Pavlova, Rayna Stoichkova; Георгиева, Снежанка Д.; Панков, Иван рец.; Pankov, Ivan rew. Date: 2005 Abstract: The paper presents the study of advanced theory development of knowledge based systems in Internet environment and its implementation in e-learning course development. The topic maps and ontology approach is used in the most recent developments in this area. The topic maps are means that could be used for creating logical structures for ... Library:
TECHNICAL UNIVERSITY - SOFIA
Title: Проектиране и спецификация на език за дефиниране на потребителски интерфейс на електронни учебни ресурси в Интернет Author: Димитрова, Тодорка С.; Dimitrova, Todorka S.; Панков, Иван рец.; Pankov, Ivan rew. Date: 2005 Abstract: The article discusses an approach for design and specification of a markup language for Internet-based eLearning GUI definition. The language called LIML is SGML and XML-compliant and provides linguistic instruments for describing the structure, the style, the content and the behavior of interface model that represents a standard eLearning ... Library:
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Title: Разработка на система за управление на водите в речен басейн и нейното приложение при обучението в областта на географските информационни системи Author: Ангелова, Мария А; Angelova, Mariya A,; Гочев, Гочо Вълев рец.; Gochev, Gocho Valev rew. Date: 2005 Abstract: The problem of the natural resources management can be successfully resolved by he combined utilization of a Geographic Information Systems and a knowledge based system. This wick presents the implementation of a developed system to a particular practical problem of finding all potential polluting objects in a Struma river basin. Thanks to ... Library:
TECHNICAL UNIVERSITY - SOFIA