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This paper analyses the changes in transfer characteristics of the vocal tract when closed by a mask, i.e. a chamber. The analysis was performed in two ways: by analytical estimation and by measurements in the vocal tract physical model for the case of mask with inner volume V = 430 cm3, corresponding to the oxygen masks used in combat airplanes. It was shown that closing the vocal tract with a mask cavity increases the first formant frequency by about 10% in front and high vowels (/e/, /i/, and /u/) and the frequencies of the first two formants by about 5% in the remaining two vowels (/a/ and /o/). It was also revealed that longitudinal and transversal resonances in the mask chamber can lead to errors in the recognition of the vowel formant frequencies. The results point to the need for additional knowledge about resonances in mask application.
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Problems associated with designing silencers are presented. Results of direct tests of silencers for cooperation with systems of axial fans, as well as results of numerical tests of a two stage acoustic silencer, are given. The numerical tests enabled determining the distribution of acoustic field inside the silencer and in the surrounding area. In those tests A sound insertion losses for different variants of installation inside the silencer, as well as for two different types of absorbing material used to fill the silencer walls, were determined. Impact of design features of silencers on effectiveness of noise reduction is described. Also, a technical sketch of a universal silencer with significant noise reduction (DipS = 39:1 dB) which can be successfully used in many ventilation systems is presented
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The present paper is comparing the results of research studies carried out for three road acoustic screens of different design and different number of damping layers. For the tests, we selected timber or steel screens with a traditional multilayer structure and also one innovative type of simplified design. With respect to particular panels, their sound absorption properties were investigated in the reverberation chamber after they had been subjected to simulated weathering. In the process, two screens were subjected to the aging tests of 50–500 cycles in a special climatic chamber, and the innovative screens were subjected to 1000 cycles. The procedure was repeated every 50 or 100 cycles in order to obtain the changes of acoustic characteristics. The changes taking place in the absorbing material were also investigated with the use of scanning electron microscopy method (SEM). Basing on the obtained results and on the statistical analysis, the capability to maintain acoustic properties by the panels during their service life in natural conditions was estimated. For that purpose, linear statistical models were worked out, which were then applied to estimate the value of the single number sound absorption coefficient after successive aging cycles as well as the predicted time periods of acoustic class changes.
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Many Haitian writers since the earthquake that destroyed Port-au-Prince in January 2010 have developed in their works of fiction the theme of writing the disaster, expressing it in various forms. The aim of this paper is to analyze the strategies adopted to write about the psychological and social effects of the cataclysmic event in two post-earthquake novels, Marvin Victor’s Corps mêlés (2011) and Makenzy Orcel’s Les Immortelles (2010). In questioning the relationship between literature and the present-time, the two Haitian writers chose different styles and forms to transpose into fiction the disruptions caused by the earthquake. We will focus our attention on two narrative strategies in particular: the interior monologue chosen by Victor and the hybrid narration preferred by Orcel.
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Fascinated with Mexico continually since childhood, J.M.G. Le Clézio publishes the, inspired by the countr y, novel Ourania in 2006. The author’s concern for the survival of the Mexican world has not escaped his critics. It is worth noting, however, that the writer’s emphasis on the role of the oral tradition in the Amerindian culture and their ecological attitudes are evident. The culture of the spoken language (along with the belief in the magic of words) is contrasted with the western culture of the written language (stressing the emptiness of words). The analysis of this issue and the study of the formal procedures by which Le Clézio moves from the spoken to the written language may give us a sense of the suggestive voice of the Mexican peoples along with their ecological attitudes. It seems that J.M.G. Le Clézio, who protects tribal societies who know how to use the world in a moderate way, promotes, among others, their respect for the natural environment.
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In his fifth novel La Nuit des morts-vivants, François Blais, a Quebec writer of the young generation, created yet another pair of kindred spirits after Iphigénie en Haute-Ville. The characters are young people addicted to all kinds of fiction, from high literature to video games, and they make reflections on the borders between fiction and reality that are worthy of a literary critic or a very conscious reader. Devoting every moment that they have at their disposal to reading books, watching films, and playing video games, Pavel and Moly are outstanding due to their erudition, even if they are simultaneously typical representatives of the generation with low-paid jobs or living on social benefits and realizing themselves only in the substitute world of fiction.
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Contemporary biographical fictions in France: between narrative and visual – This paper discusses an evolution of point of view on biographical fictions from 90’ to the present, due to the important increase of literary practices exploring images and their role in the constitution of the biographical discourse. The relation between fiction and reality presented from the point of view of Paul Ricoeur’s ‘narrative identity’ in first approaches of biographical fictions is now substituted by the reflection about the relation between narrative and visual which discloses, particularly in the case of biographical portraits of writers, the commemorative aspects of a literary text.
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Micro-(h)istorical narratives by Claude Duneton and Jean Echenoz – The purpose of this article is a comparative study of two recent French novels, Le Monument. Roman vrai by Claude Duneton (2004) and 1914 by Jean Echenoz (2012), which, in spite of formal and ideological differences, approach the theme of the Great War in a way similar to micro-historical frameworks. Like historians representing this field of historiography, both writers depict the four years of the First World War by focusing on a small community and a geographical space limited to a small location on the home-front. Referring to the distinction between roman de l’historien (the historian’s novel) and roman du témoin (the witness’s novel) proposed by Emmanuel Bouju, the author of the article analyses the strategies used by the novelists to create an indirect witness’s point-of-view, juxtaposed with the perspective of the contemporary recipient of the events that happened a hundred years ago.
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Tanguy Viel’s novels are peculiar variations on well-known novelistic genres: they creatively re-work familiar plot configurations, narrative strategies and thematic concerns. It would appear that this subversive re-activation of the genre can be related to this contemporary literary aesthetics which foregrounds blurring of generic boundaries and mixing of traditional forms. In this context the ambiguous generic status of Viel’s fiction deserves close scrutiny, which is precisely the aim of the present paper: it analyses his last novel Paris-Brest (2009) within the framework of selected contemporary theories of genre.
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In father’s footsteps or a problematic filiation. Dominique Jamet’s case – There is a phenomenon to be observed in contemporary French literature, namely the renewal of the novel through writing about self and the day-to-day reality in the context of family history. Writers reach into the past, often traumatic and painful, in order to rebuild their own broken identity, scarred by the memory of their parents’ troubled past. This is the case with Dominique Jamet. He returns to history with a capital H (the interwar period, World War Two, the Vichy regime and the subsequent issues of accounting for collaboration), so as to draw the figure of his father, Claude, an “intellectual” turncoat. The questionable filiation is the point of departure for writing two autobiographical texts. Also, it had undoubtedly been an inspiration for Un traître, a novel published in 2008, which is a fictitious reconstruction of the biography of Jacques Vasseur, an infamous French collaborator.
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Palynological and archaeobotanical analyses were conducted on excavated sediments from Tse Dura, a Later Stone Age rock shelter in north-central Nigeria with the aim of reconstructing the environment conditions at the site within the last millennium. From 933 ± 29 BP to 802 ± 29 BP, the environment alternated between Guinea savanna with dry conditions, and secondary and riverine forests with humid conditions. During these periods of environmental fluctuations, the LSA populations engaged in the management of economic plants the most significant of which included Dioscorea spp. Pennisetum glaucum and Elaeis guineensis, and exploited wild plants such as Pavetta crassipes, Sarcocephalus latifolius and Lophira cf. lanceolata for dietary and ethnomedicinal purposes. Around 310 ± 30 BP cal, the environment became very wet after which it was succeeded by a drier period. It was during this period that Sorghum bicolor became prominent, and the environment attained its current status dominated by Guinea savanna elements and secondary forests.
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The site at Orłowo Cliff was used to analyse the stratigraphic position and palaeogeographic interpretations of the properties and depositional conditions of two basal tills from the Late Pleistocene. A multi-proxy approach involved lithofacies, petrographic analysis of the fine gravel fraction, analyses of indicator erratics and till fabric. TL dating of intra-moraine deposits was used to determine depositional time frames of tills. The sediment profile at Orłowo Cliff shows a distinct reduction in number of Pleistocene units. Obtained dating results suggest the presence of Middle and Late Pleistocene fluvial units. The main issue discussed is the stratigraphic position of the older till (Unit O-4). It can be assumed that this till was deposited probably during the Middle Weichselian (MIS4). At Orłowo Horn the till of Unit O-4 reveals incorporation of the erratic material derived from an older till in the surrounded area (according to petrographic composition – probably from MIS 8). The younger till (Unit O-6) was deposited in the Late Weichselian (MIS 2). Moreover, the till of Unit O-6 is characterised by a significant shift towards the south-west in terms of the erratic origin in Unit O-4.
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Although much has been written about a cosmic impact event in the Western Alps of the Mt. Viso area, the event closely tied with the Younger Dryas Boundary (YDB) of 12.8 ka and onset of the Younger Dryas (YD), the affected land surface is considered to contain a similar black mat suite of sediment found on three continents. While work elsewhere has focused on recovered sediment from lake and ice cores, buried lacustrine/alluvial records, and surface glacial and paraglacial records, no one has traced a mountain morphosequence of deposits with the objective of investigating initial weathering/ soil morphogenesis that occurred in ice recessional deposits up to the YDB when the surface was subjected to intense heat, presumably, as hypothesized by Mahaney et al. (2016a) from a cosmic airburst. With the land surface rapidly free of ice following glacial retreat during the Břlling-Allerřd interstadial, weathering processes ~13.5 to 12.8 ka led to weathering and soil morphogenesis in a slow progression as the land surface became free of ice. To determine the exposed land character in the mid- to late-Allerřd, it is possible to utilize an inverted stratigraphic soil morphogenesis working backward in time, from known post-Little Ice Age (LIA) (i.e. time-zero) through LIA (~0.45 to ~0.10 ka), to at least the middle Neoglacial (~2 ka), to answer several questions. What were the likely soil profile states in existence at the end of the Allerřd just prior to the cosmic impact/airburst (YDB)? Assuming these immature weathered regolith sections of the Late Allerřd approximated the <1 ka old profiles seen today, and assuming the land surface was subjected to a hypothesized instant temperature burst from ambient to ~2200oC at ~12.8 ka, what would be the expected effect on the resident sediment? To test the mid-LG (YDB) to YD relationship we analyzed the paleosols in both suites of deposits – mid-LG to YD – to test that the airburst grains are restricted to Late Allerřd paleosols and using relative-age-determination criteria, that the overlapping YD to mid-LG moraines are closely related in time. These are some of the questions about the black mat that we seek to answer with reference to sites in the upper Guil and Po rivers of the Mt. Viso area.
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Archaeology of north-eastern Poland has been poorly recognized owing to vast forest areas and numerous lakes. This particularly refers to the Warmian–Masurian Voivodship, where forest covers over 30% of its area. Prospection of forested areas has become possible in Poland just over 10 years ago with the Airborne Laser Scanning (ALS) and Light Detection and Ranging (LiDAR). These techniques allow obtaining 3-D documentation of recognized and also unknown archaeological sites in the forested areas. Thanks to ALS/LiDAR prospection a significant number of archaeological structures have been identified also in the Warmia and Masuria regions. Among them oval-shaped hillforts, surrounded by perfectly spaced concentric moats and ramparts, located mainly on islands and in wetland areas, have raised particular attention. Based on field prospection and results of preliminary excavations, these objects have been considered as Iron Age hillforts. One of the best preserved objects of this type is on the Radomno Lake island, located several kilometres to the south of Iława town. Integrated geoarchaeological prospection of this hillfort emphasized benefits of using LiDAR in combination with results of geophysical prospection and shallow drillings. Applied methodology enabled to document the hillfort shape, and to study its geological structure and stratigraphy. The results clearly indicate that integration of LiDAR data with geophysical prospecting is indispensable in future archaeological surveys. It is a perfect tool for remote sensing of archaeological objects in forest areas, so far not available for traditional archaeology.
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The paper deals with frequency estimation methods of sine-wave signals for a few signal cycles and consists of two parts. The first part contains a short overview where analytical error formulae for a signal distorted by noise and harmonics are presented. These formulae are compared with other accurate equations presented previously by the authors which are even more accurate below one cycle in the measurement window. The second part contains a comparison of eight estimation methods (ESPRIT, TLS, Prony LS, a newly developed IpDFT method and four other 3-point IpDFT methods) in respect of calculation time and accuracy for an ideal sine-wave signal, signal distorted by AWGN noise and a signal distorted by harmonics. The number of signal cycles is limited from 0.1 to 3 or 5. The results enable to select the most accurate/ fastest estimation method in various measurement conditions. Parametric methods are more accurate but also much slower than IpDFT methods (up to 3000 times for the number of samples equal to 5000). The presented method is more accurate than other IpDFT methods and much faster than parametric methods, which makes it possible to use it as an alternative, especially in real-time applications.
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Noise spectroscopy as a highly sensitive method for non-destructive diagnostics of semiconductor devices was applied to solar cells based on crystalline silicon with a view to evaluating the quality and reliability of this solar cell type. The experimental approach was used in a reverse-biased condition where the internal structure of solar cells, as well as pn-junction itself, was electrically stressed and overloaded by a strong electric field. This gave rise to a strong generation of a current noise accompanied by local thermal instabilities, especially in the defect sites. It turned out that local temperature changes could be correlated with generation of flicker noise in a wide frequency range. Furthermore, an electrical breakdown in a nonstable form also occurred in some specific local regions what created micro-plasma noise with a two-level current fluctuation in the form of a Lorentzian-like noise spectrum. The noise research was carried out on both of these phenomena in combination with the spectrally-filtered electroluminescence mapping in the visible/near-infrared spectrum range and the dark lock-in infrared thermography in the far-infrared range. Then the physical origin of the light emission from particular defects was searched by a scanning electron microscope and additionally there was performed an experimental elimination of one specific defect by the focused ion beam milling.
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Due to the difficulty of detecting traces of organic acid mixture in an aqueous sample and the complexity of resolving UV-Vis spectra effectively, a combinatory method based on a self-made radical electric focusing solid phase extraction (REFSPE) device, UV-Vis detection and partial least squares (PLS) calculation is proposed here. In this study, REFSPE was used to enhance the extraction process of analytes between the aqueous phase and the membrane phase to enrich the trace of mixed organic acid efficiently. Then, the analytes, which were eluted from the adsorption film by ethanol with the assistance of an ultrasonic cleaning machine, were detected with UV-Vis spectrophotometry. After that, the PLS method was introduced to solve the problem of overlapping peaks in UV-Vis spectra of mixed substances and to quantify each compound. The linearly dependent coefficients between the predicted value of the model and the actual concentration of the sample were all higher than 0.99. The limit values of detection for benzoic acid, phthalic acid and p-toluene sulfonic acid were found at 9.9 #22;g/L, 12.2 #22;g/L and 13.8 #22;g/L with the relative recovery values between 84.8% and 117.9%. The RSD (n = 20) values of each component are 1.17%, 1.11% and 0.86%, respectively. Therefore, the proposed combined method can determine traces of complex materials in an aqueous sample efficiently and has wonderful potential applications.
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Automatic gender detection is a process of determining the gender of a human according to the characteristic properties that represent the masculine and feminine attributes of a subject. Automatic gender detection is used in many areas such as customer behaviour analysis, robust security system construction, resource management, human-computer interaction, video games, mobile applications, neuro-marketing etc., in which manual gender detection may be not feasible. In this study, we have developed a fully automatic system that uses the 3D anthropometric measurements of human subjects for gender detection. A Kinect 3D camera was used to recognize the human posture, and body metrics are used as features for classification. To classify the gender, KNN, SVM classifiers and Neural Network were used with the parameters. A unique dataset gathered from 29 female and 31 male (a total of 60 people) participants was used in the experiment and the Leave One Out method was used as the cross-validation approach. The maximum accuracy achieved is 96.77% for SVM with an MLP kernel function.
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The paper presents the properties of a strain sensor, which was made using the micro hole collapse method and operates in the configuration of a Mach-Zehnder modal interferometer with a PM-1550-01 polarization maintaining photonic crystal fibre. The sensor’s transfer curve was determined analytically. Its strain sensitivity, determined from measurements, decreases slightly with increasing wavelength and is in a range from 􀀀2:01 to 􀀀2:23 pm/me in the wavelength range 1520–1580 nm. Based on the Fourier analysis of the wavelength spectrum of the constructed sensor, the difference of the group refractive indices of the core and the cladding of the photonic crystal fibre was determined, which are in a range from 7:45#1;10􀀀3 to 1:01#1;10􀀀2. The temperature sensitivity of the sensor, determined on the basis of measurements performed in a range from 23 to 60◦C, is positive and equals 5.9 pm/K.
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Development of facial recognition or expression recognition algorithms requires input data to thoroughly test the performance of algorithms in various conditions. Researchers are developing various methods to face challenges like illumination, pose and expression changes, as well as facial disguises. In this paper, we propose and establish a dataset of thermal facial images, which contains a set of neutral images in various poses as well as a set of facial images with different posed expressions collected with a thermal infrared camera. Since the properties of face in the thermal domain strongly depend on time, in order to show the impact of aging, collection of the dataset has been repeated and a corresponding set of data is provided. The paper describes the measurement methodology and database structure. We present baseline results of processing using state-of-the-art facial descriptors combined with distance metrics for thermal face reidentification. Three selected local descriptors, a histogram of oriented gradients, local binary patterns and local derivative patterns are used for elementary assessment of the database. The dataset offers a wide range of capabilities – from thermal face recognition to thermal expression recognition.
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In this paper, two new sinusoidal signal frequency estimators calculated on the basis of four equally spaced signal samples are presented. These estimators are called four-point estimators. Simulation and experimental research consisting in signal frequency estimation using the invented estimators have been carried out. Simulation has also been performed for frequency tracking. The simulation research was carried out applying the MathCAD computer program that determined samples of a sinusoidal signal disturbed by Gaussian noise. In the experimental research, sinusoidal signal samples were obtained by means of a National Instruments PCI-6024E data acquisition card and an Agilent 33220A function generator. On the basis of the collected samples, the values of four-point estimators invented by the authors and, for comparison, the values of three- and four-point estimators proposed by Vizireanu were determined. Next, estimation errors of the signal frequency were determined. It has been shown that the invented estimators can estimate a signal frequency with greater accuracy.
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