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For economical work of turbogenerators it is necessary to ensure a steady rhythm of hot steam supply. Blowing ventiliators must be fed with very hot steam. It is very important if the efficiency coefficient is to be raised. All defects must be diagnosed as soon as posible and it will ensure a steady rhythm of system work.
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In coordination procedure generators outages consideration as well as lines outages are important. Asynchronous generators, which are intensively used in wind turbines, cannot usually sustain their fault currents contribution during the coordination period. It is possible that they are disconnected from the network before the fault is cleared. Therefore, wind turbines with asynchronous generator consideration are more important than others. These features produce additional constraints in optimal coordination schemes. This paper investigates the effects of wind turbines in optimal coordination of Overcurrent (OC) relays and defines the additional terms in optimal constraints due to the disconnection of wind turbines. The proposed method was applied in a power system, the results of the applied method are shown and the wind turbines effects are clarified in the paper.
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Hand gestures provide an attractive alternative to cumbersome interface devices for human-computer interaction (HCI). In particular, visual interpretation of hand gestures can help in achieving the ease and naturalness desired for HCI. The computer vision method was selected for hand pose recognition. The aim of the current study was to evaluate the performance of eigen images approach for hand gesture recognition. Earlier studies have shown that the approach was successfully used for face recognition task. The experimental results showed that using 10 eigen images the Euclidean distance to own class centre is about 5 times less than to other centres. This leads to a good classification of hand pose images. There is a need for a good pre-processing of images before image decomposition to eigen images.
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We can see our vision possibilities in human life. Moreover, today we are doing investigations on vision features inclusion into social and especially in scientific spheres. We many did research on vision tracking methods. In this paper the principal position of stereo vision implementation in the eye movement detection problem is discussed. Our engineers’ purpose is to define new methods using human eye to make a person’s life more comfortable. In this investigation new methods of eye tracking by the use of stereo vision were developed. As a framework of the research a special purpose investigative case was built where artificial eye balls and digital cameras were mounted. By using the Software Development Kit of Microsoft Corporation product DirectX was written for special software, which can show the possibility of making, transforming and rendering stereo vision by using two or more digital video cameras. As digital video cameras Creative WebCam NX products were used. To make them work properly simple methods in camera calibration were used. In this investigation special attention was paid to software development, which was used for new algorithms to get, calculate and render video and image data for the implementation of stereo vision in researches of eye movements.
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In this paper breakdown‘s flow of the Distributing electricity network 0,4–10 kV is presented. The breakdown’s information of one Electricity network department is analyzed. In the research of 2002–2004 the statistical data was used, the literature on the subject was discussed and synthesized, graphic modeling of statistical data was made. The forecast of breakdowns of Distributing electricity network 0,4–10 kV, embracing that the breakdowns count is distributed by normal distribution. The analysis of the flow of breakdowns showed that the state of Distributing electricity network 0,4–10 kV is to by upgraded.
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Ptresam commands (SSE2) for videooculography measuring methods of eyes movements in this activity (an ÿtresamÿ by straight lines and an ÿtresamÿ by a circle) were adapted. By their assistance the time of detection methods of eye pupil centre ÿtresamÿtes was accelerated. The algorithm of eye pupil centre detection, in which the methods of ÿtresamÿ by straight lines and ÿtresamÿ by circles were used was presented. Ptresam commands (SSE2) and the methods of their use were presented. After the investigetion it was determined that the time of eye pupil centre ÿtresamÿtes by the assistance of ÿtresam commands was accelerated.
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The aim of the research paper is to develop sound waveforms database for concatenative speech synthesis in Lithuanian. The features of the phonemes and diphones are examined in the paper. The final result of the work is the sound database for the Lithuanian language incorporating the phonemes and diphones. Synthesizer of the Lithuanian language may be developed using this sound database. To implement this work the program PRAAT was used. This software was selected due to its flexibility in the acoustic analysis of speech signals. The paper includes: 1. Analysis of the general functional diagram of speech synthesis by text as well as the principles of concatenate synthesis. 2. Compilation and analysis of the versions of the diphones most commonly used in the Lithuanian language. 3. Description of the speech synthesis experiment using the recorded phonemes and diphones. 4. Recommendations for the improvement of the Lithuanian sound set and the quality of the signal to be synthesized.
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Video-based techniques allow us to refuse search of coils for ocular torsion determination. We chose to use image processing in acquired video frames and to produce pattern matching using cross-correlation for eye torsional measurement. Iris texture was used for this type of analysis. After a series of simulations we determined that a crosscorrelation method was suitable for it. Moreover, we determined that the right iris band filtration, a mask size and a search zone size were very important for getting correct correlation results. However, measurements of the real eye will force us to consider the distortion of the results influenced by a specific geometrical eye form.
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Speech recognition technologies appeared in the period of general device miniaturization, when all technologies were commonly integrated into one chip. There is no space for buttons and displays anymore. In order to have a good system of speech recognition in Lithuanian a number of researches must be implemented. Only after selecting the most efficient speech recognition scheme we can proceed to the development of software adapted to the contemporary time. The aim of this paper is to determine how efficient speech recognition is possible using neuron networks. MFCC and LPC coefficients were chosen as the parameters characterizing the phonemes. The paper attempts determin the coefficients, which lead to the most efficient recognition of the phonemes. For testing programs PRAAT and MatLab were used. After the implementation of a number of phoneme recognition experiments in the research work the results were obtained, which lead to the following conclusions: 1. In case of using neuron network for the recognition of isolated sounds and characterizing the phonemes by MFCC or LPC coefficients, the possibility of recognition does not exceed 90 per cent. It is not enough for quality recognition of Lithuanian speech. 2. In case of using MFCC coefficients the phonemes are recognized better than using LPC coefficients. The average difference is about 15 percent. 3. The phoneme recognition rate increases when a speech signal is normalized before the coefficients extraction. _______: Lithuanian speech, vowels, diphthongs, speech recognition technologies, neuron networks, MFCC and LPC coefficients.
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The genealogical structure of Žemaitukai horses is being formed in two ways, first, by developing from the zootechnical lines as many as possible genealogical lines with distinct traits and, second, by developing new unrelated lines. Currently there are four new lines being developed and among them the Saturnas line, the founder of which was chosen to be a heavy-type Žemaitukai horse, is most successfully developing. The initial studies of foal growth and development indicated that there were greater differences in the weight and body measurements of foals than of fillies of the Saturnas line in comparison with purebred horses. The founders and their progeny of the new lines accounted for 17.4% in the genealogical structure of the Žemaitukai breed, but after selection this number decreased to 12.4% and it is planned to leave no more than 10% of the most typical horses after the next selection and to study their influence on the genetic structure of the Žemaitukai breed.
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The World Wide Web overwhelms us with immense amounts of widely distributed, interconnected, rich, and dynamic hypertext information. For the retrieval of necessary information it is necessary to use search engines. Their usage efficiency depends on the concordance of presentation results with user query, which commonly determines a search engine indexing technique. The indexing process result is processing Internet document collection so docs containing a query word can be retrieved faster, i. e. sculpt a document, which favors for the search engine structure. Later the available indexing information will compress and rank pages. The following process influences the rate of query results retrieval and representation. According to factors deciding the anatomy and efficiency of these processes the article treats the indexing algorithm, which at the meantime is applicable for a real Internet search engine.
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At the beginning all machines ran a single process. While running a program, it had an exclusive use of all resources of the computer. Later things moved on. The concept of multiple threads of execution first appeared with time sharing systems where more than one person could be logged into a central mainframe computer at once. It was important to ensure that the processing time of the machine was fairly divided between all users, and the operating systems of the time made use of the „process“ and „thread“ concepts. Early DOS and Windows systems were single tasking. The program ran exclusively on the machine or not at all. With increasingly sophisticated applications and an increasing demand for personal computers, especially with respect to high performance in the graphics and networking areas, multiprocess and multithread operating systems are now commonplace. Multithreading on PCs has been mainly driven by the need for better performance and usability. Threads are useful doing lengthy processing, background processing, I/O work and making use of multiprocessor systems. The usage of threads raises additional challenges such as synchronization of threads and deadlock prevention. These problems can be solved by using „Critical Sections“, appropriate functions and other techniques.
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The vision system is very important for perception of ambience, objects setting in the space. It is important what we can know about recognition and ambience analysing the vision system. We made some experiments in order to verify two hypothecs which say that each sacade moves to look at the place where we get new information and that the change of similar images causes tiredness, loss of interest and they mute perception. We made experiments using a video camera. The left eye of the investigator is filmed when he examines a given picture. The Filmed material is procesed with a special program designed at Šiauliai University. Later that material is procesed with MatLab. From the experiments we found out that when a person sees an image for the first time he hopes to get more information and fixes his look at separate details, forms, colours. But when a person sees a similar image several times, he looses interest, becouse his vew can not give more information. Equal or similar images cause tiredness, interest sinks and it mutes perception.
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The research of the orientation of the parts is presented in the paper. The orientation of the parts with the use of automatic search is an advanced method. It enables to improve reliability and accuracy of assembling. The identification of an optimal searching mode was performed by the digital analysis method. This mode estimates searching trajectory composed of two steps. The drawn curves allow to choose optimal parameters of the assembling mechanism.
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