An article focuses on the new methods for automatic processing and analysis of the scientific papers. It covers the very first part of this task – discovery and harvesting of scientific publications from the internet. Article is focused on discovery and analysis of the html documents to identify publication resources. Usage of data from Common Crawl project allows operating on large subset of the web pages without a need to perform an expensive crawl of the WWW. We present methods for automatic identification of pages describing scholarly documents in WWW network using html meta headers. Presented set of rules applied to the data achieves reasonable quality. A system based on these tools is also presented. It allows easy operating and transferring output to the COntent ANalysis SYStem(CoAnSys) - a processing and analysis system developed in ICM. For achieving this goal set of MapReduce tasks running with Hadoop And Ozzie has been used. The quality and efficiency of described rules are discussed. Finally future challenges for our system are presented.
W artyukule przedstawiono pewną metodę zmniejszania blędów kwantyzacji w procesie pomiaru stosunku napięć. Proponowana metoda polega na wykonaniu dodatkowego pomiaru trzeciego napięcia, będącego różnicą wymienionych napięć. Wyrażając wynik pomiaru stosunku napięć jako pewną funkcję wyników trzech pomiarów napięć można uzyskać zmniejszenie błędu kwantyzacji.
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The paper presents the method of decrease of quantization errors in measurement of voltages and their ratio. The method suggested in the paper is based on the additional measurement of the third voltage wchich is the difference of the voltages mentioned above. When measurement results of the voltages ratio is expressed as a result function of three voltages measurements, the decrease of quantisation errors can be obtained.
W artykule przedstawiono wersję metody korekcji błędu dynamicznego w niestacjonarnych torach analogowych pierwszego rzędu. Metoda wymaga tylko wzorcowania statycznego jednego z dwu torów pomiarowych. System pomiarowy wykorzystujący tę metodę przeprowadza identyfikację niestacjonarnych dynamicznych własności obu torów pomiarowych i statycznych drugiego toru wykorzystując, do tego celu, tylko sygnały pomiarowe. Następnie przeprowadza korekcję błędu dynamicznego. Zaprezentowano wyniki badań symulacyjnych dla zmieniających się okresowo dynamicznych własności torów analogowych i sygnału. Oszacowano wpływ szumu kwantyzacji przetworników A/C na dokładność korekcji.
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A version of the method of dynamic error correction for the I-st order time-varying analog channel is presented in the paper. The method needs two analog channels and the statical calibration of the only one of measuring channel is required. Measurement system using the method identifies time-varying dynamic features of both measuring channels as well as statical features of the one of them using measurement signals only. Then the system performs dynamic error correction. Measurement of the instantaneous temperature at the pulsatory gas flow may be shown as an exemplary application, in which the presented method can be applied. Results of simulation research are presented for the case, when the dynamic features of analog channels and signal are changing periodically with the same period. The influence of the A/D resolution onto precision of the executed correction has been examined.
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W artykule opisano historię kopalni "Królowa Luiza" położonej w Zabrzu. a której początki sięgają roku 1791. Rozwój górnictwa węgla kamiennego na Górnym Śląsku związany był z działalnością władz pruskich, które po podboju tych ziem zainteresowały się bogactwami mineralnymi, szczególnie rudami srebra i ołowiu w okolicy Tarnowskich Gór. Obiektem ściśle związanym z dawną kopalnia "Królowa Luiza" była Główna Kluczowa Sztolnia Dziedziczna, do budowy której skłoniły śląskie władze górnicze wysokie koszty odwadniania i transportu węgla.
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The article describes the history of "Queen Luiza" Mine located in Zabrze, the beginning of which date back to 1791. Hard coal mining development in Upper Silesia is connected with the activities of Prussian authorities which after conquering the land started to be interested in minerals wealth, especially with silver and lead ores nearby Tarnowskie Góry. The Main Key Inheritance Gallery was the object strictly connected with ."Queen Luiza" ex-mine. The costs of dewatering and coal transportation enforced the Silesian mining authorities to construct the gallery.
The paper deals with experimental verification of results provided by theoretical approach to the problem of sound radiation from an unflanged duct with mean flow of the medium taking into account existence of all allowable wave modes and, in particular, occurrence of the so-called unstable wave, which results in decay of radiation on and in vicinity of the duct axis. The flow is assumed to be uniform with the source of flow located inside the duct, which is the case frequently occurring in industrial systems. Mathematical considerations, accounting for multimodal and multifrequency excitation and diffraction at the duct outlet, are based on the model of the semi-infinite unflanged hard duct with flow. In the experimental set-up a fan, mounted inside the duct served as the source of flow and noise at the same time modelled as an array of uncorrelated sources of broadband noise, what led to the axisymmetrical shape of the sound pressure directivity characteristics. The theoretical analysis was carried out for the root mean square acoustic pressure in the far-field conditions. Experimental results are presented in the form of the measured pressure directivity characteristics obtained for uniform flow directed inwards and outwards the duct compared to this observed for the zero-flow case. The directivity was measured in one-third octave bands throughout five octaves (500 Hz – 16 kHz) which, for a duct with radius of 0.08 m, corresponds to the range 0.74–23.65 in the reduced frequency ka (Helmholtz number) domain. The results obtained are consistent with theoretical solutions presented by Munt and Savkar, according to whom the weakening of the on-axis and close-to-axis radiation should take place in the presence of medium flow. Experimental results of the present paper indicate that this effect is observed even for the Mach number as low as 0.036.
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It is convenient to have a device and a method of generating single cut-on modes in cylindrical hard-walled waveguides or at least in laboratory models of such systems. This allows to examine, among other things, properties of various active and/or passive elements inserted in a cylindrical duct by testing them in conditions when the incident (input) wave comprises only one cut-on mode and determining the reflection and transmission coefficients for single selected incident modes. As it has been already demonstrated by the present authors, it is possible to generate single cut-on modes in a circular duct using a small (although increasing with mode order) number of acoustic monopoles arranged properly on a duct cross-section and driven with appropriate acoustic volume amplitudes and phases. Laboratory models of such sources are proposed in this paper and results of tests verifying their directional properties are presented. The other technical issue relating to practical utilization of the proposed method is the possible error introduced by the apparatus used for scanning the acoustic field inside the duct model. It is shown that insertion of the measuring probe changes the total energy radiated into the free space only by a fraction of a decibel.