Search results for: blind speech separation

Authors: M.R Asghari Bejestani, Gh. R. Mohammad Khani, V.R. Nafisi

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Imagined speech recognition is one of the most interesting approaches to BCI development and a lot of works have been done in this area. Many different experiments have been designed and hundreds of combinations of feature extraction methods and classifiers have been examined. Reported classification accuracies range from the chance level to more than 90%. Based on non-stationary nature of brain signals, we have introduced 3 classification modes according to time difference in inter and intra-class samples. The modes can explain the diversity of reported results and predict the range of expected classification accuracies from the brain signal accusation procedure. In this paper, a few samples are illustrated by inspecting results of some previous works.

Keywords: brain computer interface, silent talk, imagined speech, classification, signal processing

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Authors: Zoran Spasovski

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The paper shortly discusses the significance and the benefits of the historical approach in the research of languages by presenting examples of it in the fields of phonetics and phonology, lexicology, morphology, syntax, and even in the onomastics (toponomy and anthroponomy). The examples from the field of phonetics/phonology include insights into animal speech and its evolution into human speech, the evolution of the sounds of human speech from vocals to glides and consonants and from velar consonants to palatal, etc., on well-known examples of former researchers. Those from the field of lexicology show shortly the formation of the lexemes and their evolution; the morphology and syntax are explained by examples of the development of grammar and syntax forms, and the importance of the historical approach in the research of place-names and personal names is briefly outlined through examples of place-names and personal names and surnames, and the conclusions that come from it, in different languages.

Keywords: animal speech, glotogenesis, grammar forms, lexicology, place-names, personal names, surnames, syntax categories

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Authors: M. Draman, S. Z. Muhamad Yassin, M. S. Alias, Z. Lambak, M. I. Zulkifli, S. N. Padhi, K. N. Baharim, F. Maskuriy, A. I. A. Rahim

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The performance of Malay automatic speech recognition (ASR) system for the call centre environment is presented. The system utilizes Kaldi toolkit as the platform to the entire library and algorithm used in performing the ASR task. The acoustic model implemented in this system uses a deep neural network (DNN) method to model the acoustic signal and the standard (n-gram) model for language modelling. With 80 hours of training data from the call centre recordings, the ASR system can achieve 72% of accuracy that corresponds to 28% of word error rate (WER). The testing was done using 20 hours of audio data. Despite the implementation of DNN, the system shows a low accuracy owing to the varieties of noises, accent and dialect that typically occurs in Malaysian call centre environment. This significant variation of speakers is reflected by the large standard deviation of the average word error rate (WERav) (i.e., ~ 10%). It is observed that the lowest WER (13.8%) was obtained from recording sample with a standard Malay dialect (central Malaysia) of native speaker as compared to 49% of the sample with the highest WER that contains conversation of the speaker that uses non-standard Malay dialect.

Keywords: conversational speech recognition, deep neural network, Malay language, speech recognition

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Authors: Arian Ebneyamini, Hoda Azimi, Jules Thibaults, F. Handan Tezel

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In this study, a modification of Hennepe model for pervaporation separation of butanol from aqueous solutions using Polydimethylsiloxane (PDMS) mixed matrix membranes has been introduced and validated by experimental data. The model was compared to the original Hennepe model and few other models which are applicable for membrane gas separation processes such as Maxwell, Lewis Nielson and Pal. Theoretical modifications for non-ideal interface morphology have been offered to predict the permeability in case of interface void, interface rigidification and pore-blockage. The model was in a good agreement with experimental data.

Keywords: butanol, PDMS, modeling, pervaporation, mixed matrix membranes

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Authors: Lana Burmistrova

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Introduction: The influence of visual impairments on several cognitive processes used in the music learning process is an increasingly important area in special education and cognitive musicology. Many children have several visual impairments due to the refractive errors and irreversible inhibitors. However, based on the compensatory neuroplasticity and functional reorganization, congenitally blind (CB) and early blind (EB) individuals use several areas of the occipital lobe to perceive and process auditory and tactile information. CB individuals have greater memory capacity, memory reliability, and less false memory mechanisms are used while executing several tasks, they have better working memory (WM) and short-term memory (STM). Blind individuals use several strategies while executing tactile and working memory n-back tasks: verbalization strategy (mental recall), tactile strategy (tactile recall) and combined strategies. Methods and design: The aim of the pilot study was to substantiate similar tendencies while executing attention, memory and combined auditory tasks in blind and sighted individuals constructed for this study, and to investigate attention, memory and combined mechanisms used in the music learning process. For this study eight (n=8) blind and eight (n=8) sighted individuals aged 13-20 were chosen. All respondents had more than five years music performance and music learning experience. In the attention task, all respondents had to identify pitch changes in tonal and randomized melodic pairs. The memory task was based on the mismatch negativity (MMN) proportion theory: 80 percent standard (not changed) and 20 percent deviant (changed) stimuli (sequences). Every sequence was named (na-na, ra-ra, za-za) and several items (pencil, spoon, tealight) were assigned for each sequence. Respondents had to recall the sequences, to associate them with the item and to detect possible changes. While executing the combined task, all respondents had to focus attention on the pitch changes and had to detect and describe these during the recall. Results and conclusion: The results support specific features in CB and EB, and similarities between late blind (LB) and sighted individuals. While executing attention and memory tasks, it was possible to observe the tendency in CB and EB by using more precise execution tactics and usage of more advanced periodic memory, while focusing on auditory and tactile stimuli. While executing memory and combined tasks, CB and EB individuals used passive working memory to recall standard sequences, active working memory to recall deviant sequences and combined strategies. Based on the observation results, assessment of blind respondents and recording specifics, following attention and memory correlations were identified: reflective attention and STM, reflective attention and periodic memory, auditory attention and WM, tactile attention and WM, auditory tactile attention and STM. The results and the summary of findings highlight the attention and memory features used in the music learning process in the context of blindness, and the tendency of the several attention and memory types correlated based on the task, strategy and individual features.

Keywords: attention, blindness, memory, music learning, strategy

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Authors: Muhammad Ali, Zeeshan Afzal, Giampaolo Ferraioli, Gilda Schirinzi, Muhammad Saleem Mughal, Vito Pascazio

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On 24 September 2019, an earthquake with 5.6 Mw and 10 km depth stroke in Mirpur. The Mirpur area was highly affected by this earthquake, with the death of 34 people. This study aims to estimate the surface deformation associated with this earthquake. The interferometric synthetic aperture radar (InSAR) technique is applied to study earthquake induced surface motion. InSAR data using 9 Sentinel-1A SAR images from 11 August 2019 to 22 October 2019 is used to investigate the pre, co-, and post-seismic deformation trends. Time series investigation reveals that there was not such deformation in pre-seismic time period. In the co-seismic time period, strong displacement was observed, and in post-seismic results, small displacement is seen due to aftershocks. Our results show the existence of a previously unpublished blind fault in Mirpur and help to locate the fault line. Previous this fault line was triggered during the 2005 earthquake, and now it’s activated on 24 September 2019. Study area is already facing many problems due to natural hazards where additional surface deformations, particularly because of an earthquake with an activated blind fault, have increased its vulnerability.

Keywords: surface deformation, InSAR, earthquake, sentinel-1, mirpur

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Authors: Ozan Kahraman, Hao Feng

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Ultrasonic atomization (UA) is a useful technique for producing a liquid spray for various processes, such as spray drying. Ultrasound generates small droplets (a few microns in diameter) by disintegration of the liquid via cavitation and/or capillary waves, with low range velocity and narrow droplet size distribution. In recent years, UA has been investigated as an alternative for enabling or enhancing ultrasound-mediated unit operations, such as evaporation, separation, and purification. The previous studies on the UA separation of a solvent from a bulk solution were limited to ethanol-water systems. More investigations into ultrasound-mediated separation for other liquid systems are needed to elucidate the separation mechanism. This study was undertaken to investigate the effects of the operational parameters on the ultrasound-mediated separation of three miscible liquid pairs: ethanol-, methanol-, and butanol-water. A 2.4 MHz ultrasonic mister with a diameter of 18 mm and rating power of 24 W was installed on the bottom of a custom-designed cylindrical separation unit. Air was supplied to the unit (3 to 4 L/min.) as a carrier gas to collect the mist. The effects of the initial alcohol concentration, viscosity, and temperature (10, 30 and 50°C) on the atomization rates were evaluated. The alcohol concentration in the collected mist was measured with high performance liquid chromatography and a refractometer. The viscosity of the solutions was determined using a Brookfield digital viscometer. The alcohol concentration of the atomized mist was dependent on the feed concentration, feed rate, viscosity, and temperature. Increasing the temperature of the alcohol-water mixtures from 10 to 50°C increased the vapor pressure of both the alcohols and water, resulting in an increase in the atomization rates but a decrease in the separation efficiency. The alcohol concentration in the mist was higher than that of the alcohol-water equilibrium at all three temperatures. More importantly, for ethanol, the ethanol concentration in the mist went beyond the azeotropic point, which cannot be achieved by conventional distillation. Ultrasound-mediated separation is a promising non-equilibrium method for separating and purifying alcohols, which may result in significant energy reductions and process intensification.

Keywords: azeotropic mixtures, distillation, evaporation, purification, seperation, ultrasonic atomization

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Authors: Luke Andrighetto, Paul G. Stevenson, Luke C. Henderson, Jim Pearson, Xavier A. Conlan

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As pseudoephedrine, a common ingredient in cold and flu medications is closely monitored and restricted in Australia, alternative methods of accessing it are of interest. The impurities and by-products of every reaction step of pseudoephedrine/ephedrine and methamphetamine synthesis have been mapped in order to develop a chemical fingerprint based on synthetic route. Likewise, seized methamphetamine contains a combination of different cutting agents and starting materials. Therefore, in-silico optimised two-dimensional HPLC with DryLab® and OpenMS® software has been used to efficiently separate complex seizure samples. An excellent match between simulated and real separations was observed. Targeted separation of model compounds was completed with significantly reduced method development time. This study produced a two-dimensional separation regime that offers unprecedented separation power (separation space) while maintaining a rapid analysis time that is faster than those previously reported for gas chromatography, single dimension high performance liquid chromatography or capillary electrophoresis.

Keywords: chemical fingerprint, ephedrine, methamphetamine, two-dimensional HPLC

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Authors: Adesola O. Orimoloye, Mohammed N. Kajama, Edward Gobina

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Gas permeation of Oxygen [O2] and Nitrogen [N2] were investigated at room temperature using 15 and 6000nm pore diameter tubular commercial alumina ceramic membranes with pressure values ranging 1.00 to 2.50 bar. The flow rates of up to 2.59 and 2.77 l/min were achieved for O2 and N2 respectively. The ratio of O2/N2 flow rates were used to compute the O2/N2 selectivity. The experimental O2/N2 selectivity obtained for 15 nm was 1.05 while the 6000 nm indicated 0.95.

Keywords: gas separation, nitrogen, oxygen, selectivity

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Authors: Hyunchul Oh

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One of the challenges in modern separation science and technology is the separation of hydrogen isotopes mixtures since D2 and H2 consist of almost identical size, shape and thermodynamic properties. Recently, quantum sieving of isotopes by confinement in narrow space has been proposed as an alternative technique. Despite many theoretical suggestions, however, it has been difficult to discover a feasible microporous material up to now. Among various porous materials, the novel class of microporous framework materials (COFs, ZIFs and MOFs) is considered as a promising material class for isotope sieving due to ultra-high porosity and uniform pore size which can be tailored. Hence, we investigate experimentally the fundamental correlation between D2/H2 molar ratio and pore size at optimized operating conditions by using different ultramicroporous frameworks. The D2/H2 molar ratio is strongly depending on pore size, pressure and temperature. An experimentally determined optimum pore diameter for quantum sieving lies between 3.0 and 3.4 Å which can be an important guideline for designing and developing feasible microporous frameworks for isotope separation. Afterwards, we report a novel strategy for efficient hydrogen isotope separation at technologically relevant operating pressure through the development of quantum sieving exploited by the pore aperture engineering. The strategy involves installation of flexible components in the pores of the framework to tune the pore surface.

Keywords: gas adsorption, hydrogen isotope, metal organic frameworks(MOFs), quantum sieving

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Authors: Ana Londral, Burcu Demiray, Marcus Cheetham

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Speech recording is a methodology used in many different studies related to cognitive and behaviour research. Modern advances in digital equipment brought the possibility of continuously recording hours of speech in naturalistic environments and building rich sets of sound files. Speech analysis can then extract from these files multiple features for different scopes of research in Language and Communication. However, tools for analysing a large set of sound files and automatically extract relevant features from these files are often inaccessible to researchers that are not familiar with programming languages. Manual analysis is a common alternative, with a high time and efficiency cost. In the analysis of long sound files, the first step is the voice segmentation, i.e. to detect and label segments containing speech. We present a comprehensive methodology aiming to support researchers on voice segmentation, as the first step for data analysis of a big set of sound files. Praat, an open source software, is suggested as a tool to run a voice detection algorithm, label segments and files and extract other quantitative features on a structure of folders containing a large number of sound files. We present the validation of our methodology with a set of 5000 sound files that were collected in the daily life of a group of voluntary participants with age over 65. A smartphone device was used to collect sound using the Electronically Activated Recorder (EAR): an app programmed to record 30-second sound samples that were randomly distributed throughout the day. Results demonstrated that automatic segmentation and labelling of files containing speech segments was 74% faster when compared to a manual analysis performed with two independent coders. Furthermore, the methodology presented allows manual adjustments of voiced segments with visualisation of the sound signal and the automatic extraction of quantitative information on speech. In conclusion, we propose a comprehensive methodology for voice segmentation, to be used by researchers that have to work with large sets of sound files and are not familiar with programming tools.

Keywords: automatic speech analysis, behavior analysis, naturalistic environments, voice segmentation

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Authors: Amulya P. Rao, Prathima S., Sreedevi N.

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Speech sound disorders (SSD) encompass the major concern in younger population of India with highest prevalence rate among the speech disorders. Children with SSD if not identified and rehabilitated at the earliest, are at risk for academic difficulties. This necessitates early identification using screening tools assessing the frequently misarticulated speech sounds. The literature on frequently misarticulated speech sounds is ample in English and other western languages targeting individuals with various communication disorders. Articulation is language specific, and there are limited studies reporting the same in Kannada, a Dravidian Language. Hence, the present study aimed to identify the frequently misarticulated consonants in Kannada and also to examine the error type. A retrospective, descriptive study was carried out using secondary data analysis of 41 participants (34-phonetic type and 7-phonemic type) with SSD in the age range 3-to 12-years. All the consonants of Kannada were analyzed by considering three words for each speech sound from the Kannada Diagnostic Photo Articulation test (KDPAT). Picture naming task was carried out, and responses were audio recorded. The recorded data were transcribed using IPA 2018 broad transcription. A criterion of 2/3 or 3/3 error productions was set to consider the speech sound to be an error. Number of error productions was calculated for each consonant in each participant. Then, the percentage of participants meeting the criteria were documented for each consonant to identify the frequently misarticulated speech sound. Overall results indicated that velar /k/ (48.78%) and /g/ (43.90%) were frequently misarticulated followed by voiced retroflex /ɖ/ (36.58%) and trill /r/ (36.58%). The lateral retroflex /ɭ/ was misarticulated by 31.70% of the children with SSD. Dentals (/t/, /n/), bilabials (/p/, /b/, /m/) and labiodental /v/ were produced correctly by all the participants. The highly misarticulated velars /k/ and /g/ were frequently substituted by dentals /t/ and /d/ respectively or omitted. Participants with SSD-phonemic type had multiple substitutions for one speech sound whereas, SSD-phonetic type had consistent single sound substitutions. Intra- and inter-judge reliability for 10% of the data using Cronbach’s Alpha revealed good reliability (0.8 ≤ α < 0.9). Analyzing a larger sample by replicating such studies will validate the present study results.

Keywords: consonant, frequently misarticulated, Kannada, SSD

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Authors: I. Schiller, D. Morsomme, A. Remacle

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Children’s ability to process spoken language develops until the late teenage years. At school, where efficient spoken language processing is key to academic achievement, listening conditions are often unfavorable. High background noise and poor teacher’s voice represent typical sources of interference. It can be assumed that these factors particularly affect primary school children, because their language and literacy skills are still low. While it is generally accepted that background noise and impaired voice impede spoken language processing, there is an increasing need for analyzing impacts within specific linguistic areas. Against this background, the aim of the study was to investigate the effect of speech-shaped noise and imitated dysphonic voice on first-grade primary school children’s speech perception and sentence comprehension. Via headphones, 5 to 6-year-old children, recruited within the French-speaking community of Belgium, listened to and performed a minimal-pair discrimination task and a sentence-picture matching task. Stimuli were randomly presented according to four experimental conditions: (1) normal voice / no noise, (2) normal voice / noise, (3) impaired voice / no noise, and (4) impaired voice / noise. The primary outcome measure was task score. How did performance vary with respect to listening condition? Preliminary results will be presented with respect to speech perception and sentence comprehension and carefully interpreted in the light of past findings. This study helps to support our understanding of children’s language processing skills under adverse conditions. Results shall serve as a starting point for probing new measures to optimize children’s learning environment.

Keywords: impaired voice, sentence comprehension, speech perception, speech-shaped noise, spoken language processing

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Authors: Hamsini Pulugurtha, P. V. S. L. Jagadamba

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Programmed Speech to Text and Text Summarization Using Graph-based Algorithms can be utilized in gatherings to get the short depiction of the gathering for future reference. This gives signature check utilizing Siamese neural organization to confirm the personality of the client and convert the client gave sound record which is in English into English text utilizing the discourse acknowledgment bundle given in python. At times just the outline of the gathering is required, the answer for this text rundown. Thus, the record is then summed up utilizing the regular language preparing approaches, for example, solo extractive text outline calculations

Keywords: Siamese neural network, English speech, English text, natural language processing, unsupervised extractive text summarization

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Authors: Dmitry Yu. Korulkin, Raissa A. Muzychkina

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In review the generalized data about different methods of extraction, separation and purification of natural and modify anthraquinones is presented. The basic regularity of an isolation process is analyzed. Action of temperature, pH, and polarity of extragent, catalysts and other factors on an isolation process is revealed.

Keywords: anthraquinones; isolation; extraction; polarity; chromatography; precipitation; bioactivity; phytopreparation; chrysophanol; aloe-emodin; emodin; physcion.

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Authors: F. R. Sultanov Ch. Daulbayev, B. Bakbolat, Z. A. Mansurov, A. A. Zhurintaeva, R. I. Gadilshina, A. B. Dugali

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Both hydrophilic-oleophobic and hydrophobic-oleophilic membranes were obtained by coating of the substrate of membranes, presented by stainless steel meshes with various dimensions of their openings, with a composition that forms the special type of their surface wettability via spray-coating method. The surface morphology of resulting membranes was studied using SEM, the type of their wettability was identified by measuring the contact angle between the surface of membrane and a drop of studied liquid (water or organic liquid) and efficiency of continuous separation of water and organic liquid was studied on self-assembled setup.

Keywords: membrane, stainless steel mesh, oleophobicity, hydrophobicity, separation, water, organic liquids

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Authors: Modupe C. Alasa

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One of the major parameters for ensuring a country’s economic growth and development is the extent to which the citizens are involved in agriculture. The general objective of this study is to determine the assessment of vocational rehabilitation of visually impaired persons in poultry farming at blind center, Ogbomoso, Nigeria. A total number of 70 students will be selected randomly through the use of structured questionnaire out of the total number of students which is 120. Data will be collected from the farmers’ personal characteristics and other specific objectives related to the work. The results will be analyzed with the use of simple statistical tools as frequency, percentage, means and standard deviations. Conclusion and recommendations will be suggested based on result findings of the study.

Keywords: assessment, impair, poultry, rehabilitation, vocational

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Authors: Ishtiaq A. Chaudhry, Z. R. Tahir, F. A. Siddiqui, Z. Anwar, F. Valenzuelacalva

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A series of experiments involving the particle image velocimetry technique are carried out to analyse the quantitative effectiveness of the synthesized vortical structures towards actual flow separation control. The streamwise vortices are synthesized from the synthetic jet actuator and introduced into the attached and separating boundary layer developed on the flat plate surface. Two types of actuators with different geometrical set up are used to analyse the evolution of vortical structures in the near wall region and their impact towards achieving separation delay on the actual aircraft wing. Firstly a single circular jet is synthesized at varying actuator operating parameters and issued into the boundary layer to evaluate the dynamics of the interaction between the vortical structures and the near wall low momentum fluid in the separated region. Secondly, an array of jets has been issued into the artificially separated region to assess the effectiveness of various vortical structures towards achieving the reattachment of the separated flow in the streamwise direction.

Keywords: boundary layer, flow separation, streamwise vortices, synthetic jet actuator

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Authors: Hiroshi Katanoda, Mohd Hazwan bin Yusof

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A theoretical investigation from the viewpoint of gas-dynamics and thermodynamics was carried out, in order to clarify the energy separation mechanism in a viscous compressible vortex, as a primary flow element in a uni-flow vortex tube. The mathematical solutions of tangential velocity, density and temperature in a viscous compressible vortical flow were used in this study. It is clear that a total temperature in the vortex core falls well below that distant from the vortex core in the radial direction, causing a region with higher total temperature, compared to the distant region, peripheral to the vortex core.

Keywords: energy separation mechanism, theoretical analysis, vortex tube, vortical flow

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Authors: Hana Porkertová, Pavel Doboš

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Based on a research project studying the experience of visually disabled people with urban space in the Czech Republic, the conference contribution discusses the limits of social-science methodologies used in sociology and human geography. It draws on actor-network theory, assuming that science does not describe reality but produces it. Methodology connects theory, research questions, ways to answer them (methods), and results. A research design utilizing ableist methodologies can produce ableist realities. Therefore, it was necessary to adjust the methods so that they could mediate blind experience to the scientific community without reproducing ableism. The researchers faced multiple challenges, ranging from questionable validity to how to research experience that differs from that of the researchers who are able-bodied. Finding a suitable theory that could be used as an analytical tool that would demonstrate space and blind experience as multiple, dynamic, and mutually constructed was the first step that could offer a range of potentially productive methods and research questions, as well as bring critically reflected results. Poststructural theory, mainly Deleuze-Guattarian philosophy, was chosen, and two methods were used: interviews and go-along interviews that had to be adjusted to be able to explore blind experience. In spite of a thorough preparation of these methods, new difficulties kept emerging, which exposed the ableist character of scientific knowledge. From the beginning of data collecting, there was an agreement to work in teams with slightly different roles of each of the researchers, which was significant especially during go-along interviews. In some cases, the anticipations of the researchers and participants differed, which led to unexpected and potentially dangerous situations. These were not caused only by the differences between scientific and lay communities but also between able-bodied and disabled people. Researchers were sometimes assigned to the assistants’ roles, and this new position – doing research together – required further negotiations, which also opened various ethical questions.

Keywords: ableist methodology, blind experience, go-along interviews, research ethics, scientific knowledge

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Authors: J. Joy, T. H. New, I. H. Ibrahim

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A computational study on bio-inspired NACA634-021 hydrofoils with leading-edge protuberances has been carried out to investigate their hydrodynamic flow control characteristics at a Reynolds number of 14,000 and different angles-of-attack. The numerical simulations were performed using ANSYS FLUENT and based on Reynolds-Averaged Navier-Stokes (RANS) solver mode incorporated with k-ω Shear Stress Transport (SST) turbulence model. The results obtained indicate varying flow phenomenon along the peaks and troughs over the span of the hydrofoils. Compared to the baseline hydrofoil with no leading-edge protuberances, the leading-edge modified hydrofoils tend to reduce flow separation extents along the peak regions. In contrast, there are increased flow separations in the trough regions of the hydrofoil with leading-edge protuberances. Interestingly, it was observed that dissimilar flow separation behaviour is produced along different peak- or trough-planes along the hydrofoil span, even though the troughs or peaks are physically similar at each interval for a particular hydrofoil. Significant interactions between adjacent flow structures produced by the leading-edge protuberances have also been observed. These flow interactions are believed to be responsible for the dissimilar flow separation behaviour along physically similar peak- or trough-planes.

Keywords: computational fluid dynamics, flow separation control, hydrofoils, leading-edge protuberances

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Authors: Ouldouz Nourani Zonouz, Mehdi Salmanpour

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Investigation and analysis of flow behavior around different shapes bluff bodies is one of the reputed topics for several years. The importance of these researches is about the unwanted phenomena called flow separation. The location of separation and the size of the wake region should be considered in different industrial designs. In this research a bluff body with D-shaped cross section has been analyzed. In circular cylinder flow separation point changes with Reynolds number but in D-Shaped cylinder there is fix flow separation point. So there is more wake steadiness in D-Shaped cylinder as compared to Circular cylinder and drag reduction because of wake steadiness. In the present work CFD simulation is carried out for flow past a D-Shaped cylinder to see the wake behavior. The Reynolds number regime currently studied corresponds to low Reynolds number and nominally two-dimensional wake. Also the effect of D-Shaped cylinders on the rate of heat transfer has been considered. Various results such as velocity, pressure and temperature contours and also some dimensionless numbers like drag coefficient, pressure coefficient and Nusselt number calculated for different cases.

Keywords: D-shaped, CFD, external flow, low Reynolds number, square cylinder

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Authors: Andre Wittenborn, Jarek Krajewski

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Trauma-related sadness in speech can alter the voice in several ways. The generation of non-linear aerodynamic phenomena within the vocal tract is crucial when analyzing trauma-influenced speech production. They include non-laminar flow and formation of jets rather than well-behaved laminar flow aspects. Especially state-space reconstruction methods based on chaotic dynamics and fractal theory have been suggested to describe these aerodynamic turbulence-related phenomena of the speech production system. To extract the non-linear properties of the speech signal, we used the time delay embedding method to reconstruct from a scalar time series (reconstructed phase space, RPS). This approach results in the extraction of 7238 Features per .wav file (N= 47, 32 m, 15 f). The speech material was prompted by telling about autobiographical related sadness-inducing experiences (sampling rate 16 kHz, 8-bit resolution). After combining these features in a support vector machine based machine learning approach (leave-one-sample out validation), we achieved a correlation of r = .41 with the well-established, self-report ground truth measure (RATS) of post-traumatic stress disorder (PTSD).

Keywords: non-linear dynamics features, post traumatic stress disorder, reconstructed phase space, support vector machine

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Authors: J. Thirunavukkarasu, M. Poulet, T. Turner, S. Pickering

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Composite waste from manufacturing can consist of different fiber materials, including blends of different fiber. Commercially, the recycling of composite waste is currently limited to carbon fiber waste and recycling glass fiber waste is currently not economically viable due to the low cost of virgin glass fiber and the reduced mechanical properties of the recovered fibers. For this reason, the recycling of hybrid fiber materials, where carbon fiber is combined with a proportion of glass fiber, cannot be processed economically. Therefore, a separation method is required to remove the glass fiber materials during the recycling process. An electrostatic separation method is chosen for this work because of the significant difference between carbon and glass fiber electrical properties. In this study, an experimental rig has been developed to measure the electrostatic charge achievable as the materials are passed through a tube. A range of particle lengths (80-100 µm, 6 mm and 12 mm), surface state conditions (0%SA, 2%SA and 6%SA), and several tube wall materials have been studied. A polytetrafluoroethylene (PTFE) tube and recycled without sizing agent was identified as the most suitable parameters for the electrical separation method. It was also found that shorter fiber lengths helped to encourage particle flow and attain higher charge values. These findings can be used to develop a separation process to enable the cost-effective recycling of hybrid fiber composite waste.

Keywords: electrostatic charging, hybrid fiber composites, recycling, short fiber composites

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Authors: Miran Sabah Ibrahim, Nahit Aktas

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The utilization of emulsifiers is highly important in the process of breaking emulsions. This examination employed five commercial demulsifiers in various temperatures for evaluating the separation efficiency. Furthermore, two different crude oils (Khurmala and Demir Dagh crude oil) were utilized for preparing emulsion. The outcomes revealed that the application commercial demulsifiers for Khurmala crude oil at 55°C and 100 ppm (KD-3100, KD-3200, FD-6144, FD-6210 and RI35Q) the separation efficiency were (78, 80.6, 78, 86 and 90 %) respectively. However, at 65 °C and 100 ppm (KD-3100, KD-3200, FD-6144, FD-6210 and RI35Q) separation efficiency were (87, 85, 91.3, 94 and 97 %) respectively. Nonetheless, utilizing Demir Dagh crude oil at 55 °C and 100 ppm (KD-3100, KD-3200, FD-6144, FD-6210 and RI35Q) resulted in the separation efficiency of (63.3, 66.6, 65, 73 and 76.6 %) respectively, and at 65 °C and 100 ppm (KD-3100, KD-3200, FD-6144, FD-6210 and RI35Q) were (77, 76.6, 80, 82 and 85 %) respectively. The combinations of FD-6144 and RI35Q at 55°C and ratio of (1:1) and (1:3) for Khurmala crude oil led to (96 and 90.6 %) efficiency respectively. However, the efficiency decreased to (98.6 and 93.3 %) respectively at 65 °C. The same combinations applied on Demir Dagh Crude oil and the results were (78 and 63.3 %) at 55 °C and (86.6 and 71 %) at 65 °C. Three different brine concentrations (NaCl) (0.5, 2 and 3.5 %) were prepared and utilized. It was found that the optimum NaCl concentration was at 3.5 % NaCl concentration for both khurmala and Demir dagh crude oil at 55 °C and 65 °C.

Keywords: demulsifier, emulsion, breaking emulsion, emulsifying agent (surfactant)

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Authors: Omar Nasr, Yasser Naguib, Mohamed Hafez

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This paper aims at providing an innovative solution for blind interference threshold estimation in an underlay cognitive network to be used in adaptive beamforming by secondary user Transmitter and Receiver. For the task of threshold estimation, blind detection of modulation and SNR are used. For the sake of beamforming several localization algorithms are compared to settle on best one for cognitive environment. Beamforming algorithms as LCMV (Linear Constraint Minimum Variance) and MVDR (Minimum Variance Distortion less) are also proposed and compared. The idea of just nulling the primary user after knowledge of its location is discussed against the idea of working under interference threshold.

Keywords: cognitive radio, underlay, beamforming, MUSIC, MVDR, LCMV, threshold estimation

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Authors: M. Pilgun

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The report presents the results of a study of the specifics of speech perception by actors of video hosting services on the material of urban planning conflicts. To analyze the content, the multimodal approach using neural network technologies is employed. Analysis of word associations and associative networks of relevant stimulus revealed the evaluative reactions of the actors. Analysis of the data identified key topics that generated negative and positive perceptions from the participants. The calculation of social stress and social well-being indices based on user-generated content made it possible to build a rating of road transport construction objects according to the degree of negative and positive perception by actors.

Keywords: social media, speech perception, video hosting, networks

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Authors: Natalia V. Ursul

Abstract:

In linguistic studies, the question of nonsense is attracting increasing interest. Nonsense is usually defined as spoken or written words that have no meaning. However, this definition is likely to be outdated as any speech act is generated due to the speaker’s pragmatic reasons, thus it cannot be purely illogical or meaningless. In the current paper a new working definition of nonsense as a linguistic medium will be formulated; moreover, the pragmatic peculiarities of newly coined linguistic patterns and possible ways of their interpretation will be discussed.

Keywords: nonsense, nonse verse, pragmatics, speech act

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Authors: Tsvetomira Braynova, Miglena Simonska

Abstract:

The article presents the results of research on phonological processes in three and four-year-old children. For the purpose of the study, an author's test was developed and conducted among 120 children. The study included three areas of research - at the level of words (96 words), at the level of sentence repetition (10 sentences) and at the level of generating own speech from a picture (15 pictures). The test also gives us additional information about the articulation errors of the assessed children. The main purpose of the icing is to analyze all phonological processes that occur at this age in Bulgarian children and to identify which are typical and atypical for this age. The results show that the most common phonology errors that children make are: sound substitution, an elision of sound, metathesis of sound, elision of a syllable, and elision of consonants clustered in a syllable. All examined children were identified with the articulatory disorder from type bilabial lambdacism. Measuring the correlation between the average length of repeated speech and the average length of generated speech, the analysis proves that the more words a child can repeat in part “repeated speech,” the more words they can be expected to generate in part “generating sentence.” The results of this study show that the task of naming a word provides sufficient and representative information to assess the child's phonology.

Keywords: assessment, phonology, articulation, speech-language development

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Authors: Ramin Dabirian, Yi Zhang, Ilias Gavrielatos, Ram Mohan, Ovadia Shoham

Abstract:

Oil-water emulsions can be found in almost every part of the petroleum industry, namely in reservoir rocks, drilling cuttings circulation, production in wells, transportation pipelines, surface facilities and refining process. However, it is necessary for oil production and refinery engineers to resolve the petroleum emulsion problems as well as to eliminate the contaminants in order to meet environmental standards, achieve the desired product quality and to improve equipment reliability and efficiency. A state-of-art Dispersion Characterization Rig (DCR) has been utilized to investigate crude oil-distilled water dispersion separation. Over 80 experimental tests were ran to investigate the flow behavior and stability of the dispersions. The experimental conditions include the effects of water cuts (25%, 50% and 75%), NaCl concentrations (0, 3.5% and 18%), mixture flow velocities (0.89 and 1.71 ft/s), and also orifice place types on the separation rate. The experimental data demonstrate that the water cut can significantly affects the separation time and efficiency. The dispersion with lower water cut takes longer time to separate and have low separation efficiency. The medium and lower water cuts will result in the formation of Mousse emulsion and the phase inversion happens around the medium water cut. The data also confirm that increasing the NaCl concentration in aqueous phase can increase the crude oil water dispersion separation efficiency especially at higher salinities. The separation profile for dispersions with lower salt concentrations has a lower sedimentation rate slope before the inflection point. Dispersions in all tests with higher salt concentrations have a larger sedimenting rate. The presence of NaCl can influence the interfacial tension gradients along the interface and it plays a role in avoiding the Mousse emulsion formation.

Keywords: oil-water dispersion, separation mechanism, phase inversion, emulsion formation

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