Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 38

Search results for: masking

38 Temporal Characteristics of Human Perception to Significant Variation of Block Structures

Authors: Kuo-Cheng Liu

Abstract:

In the latest research efforts, the structures of the image in the spatial domain have been successfully analyzed and proved to deduce the visual masking for accurately estimating the visibility thresholds of the image. If the structural properties of the video sequence in the temporal domain are taken into account to estimate the temporal masking, the improvement and enhancement of the as-sessing spatio-temporal visibility thresholds are reasonably expected. In this paper, the temporal characteristics of human perception to the change in block structures on the time axis are analyzed. The temporal characteristics of human perception are represented in terms of the significant variation in block structures for the analysis of human visual system (HVS). Herein, the block structure in each frame is computed by combined the pattern masking and the contrast masking simultaneously. The contrast masking always overestimates the visibility thresholds of edge regions and underestimates that of texture regions, while the pattern masking is weak on a uniform background and is strong on the complex background with spatial patterns. Under considering the significant variation of block structures between successive frames, we extend the block structures of images in the spatial domain to that of video sequences in the temporal domain to analyze the relation between the inter-frame variation of structures and the temporal masking. Meanwhile, the subjective viewing test and the fair rating process are designed to evaluate the consistency of the temporal characteristics with the HVS under a specified viewing condition.

Keywords: temporal characteristic, block structure, pattern masking, contrast masking

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37 Contrast Enhancement in Digital Images Using an Adaptive Unsharp Masking Method

Authors: Z. Mortezaie, H. Hassanpour, S. Asadi Amiri

Abstract:

Captured images may suffer from Gaussian blur due to poor lens focus or camera motion. Unsharp masking is a simple and effective technique to boost the image contrast and to improve digital images suffering from Gaussian blur. The technique is based on sharpening object edges by appending the scaled high-frequency components of the image to the original. The quality of the enhanced image is highly dependent on the characteristics of both the high-frequency components and the scaling/gain factor. Since the quality of an image may not be the same throughout, we propose an adaptive unsharp masking method in this paper. In this method, the gain factor is computed, considering the gradient variations, for individual pixels of the image. Subjective and objective image quality assessments are used to compare the performance of the proposed method both with the classic and the recently developed unsharp masking methods. The experimental results show that the proposed method has a better performance in comparison to the other existing methods.

Keywords: unsharp masking, blur image, sub-region gradient, image enhancement

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36 Speech Enhancement Using Wavelet Coefficients Masking with Local Binary Patterns

Authors: Christian Arcos, Marley Vellasco, Abraham Alcaim

Abstract:

In this paper, we present a wavelet coefficients masking based on Local Binary Patterns (WLBP) approach to enhance the temporal spectra of the wavelet coefficients for speech enhancement. This technique exploits the wavelet denoising scheme, which splits the degraded speech into pyramidal subband components and extracts frequency information without losing temporal information. Speech enhancement in each high-frequency subband is performed by binary labels through the local binary pattern masking that encodes the ratio between the original value of each coefficient and the values of the neighbour coefficients. This approach enhances the high-frequency spectra of the wavelet transform instead of eliminating them through a threshold. A comparative analysis is carried out with conventional speech enhancement algorithms, demonstrating that the proposed technique achieves significant improvements in terms of PESQ, an international recommendation of objective measure for estimating subjective speech quality. Informal listening tests also show that the proposed method in an acoustic context improves the quality of speech, avoiding the annoying musical noise present in other speech enhancement techniques. Experimental results obtained with a DNN based speech recognizer in noisy environments corroborate the superiority of the proposed scheme in the robust speech recognition scenario.

Keywords: binary labels, local binary patterns, mask, wavelet coefficients, speech enhancement, speech recognition

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35 Chaotic Control, Masking and Secure Communication Approach of Supply Chain Attractor

Authors: Unal Atakan Kahraman, Yilmaz Uyaroğlu

Abstract:

The chaotic signals generated by chaotic systems have some properties such as randomness, complexity and sensitive dependence on initial conditions, which make them particularly suitable for secure communications. Since the 1990s, the problem of secure communication, based on chaos synchronization, has been thoroughly investigated and many methods, for instance, robust and adaptive control approaches, have been proposed to realize the chaos synchronization. In this paper, an improved secure communication model is proposed based on control of supply chain management system. Control and masking communication simulation results are used to visualize the effectiveness of chaotic supply chain system also performed on the application of secure communication to the chaotic system. So, we discover the secure phenomenon of chaos-amplification in supply chain system

Keywords: chaotic analyze, control, secure communication, supply chain attractor

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34 “Fake It Till You Make It”: A Qualitative Study into the Well-being of Autistic Women

Authors: Kathleen Seers, Rachel Hogg

Abstract:

Diagnosis of Autism Spectrum Disorder (ASD) in women is increasing, prompting research into the presentation of female ASD and exploring why females are failing to meet the diagnostic threshold. One explanation is the use of masking behaviors, where traits of ASD are suppressed and gender-appropriate behaviors are mimicked to reduce the visibility and victimization of ASD girls. Current research explores ASD presentation and the lived experiences of ASD girls and adolescents; however, there is a paucity of literature in relation to the intra- and inter- psychic experiences of ASD women. Through a social constructionist framework, this qualitative study sought to understand how the construction of gender and the medicalisation of ASD influences women’s experiences of ASD. This study also explored the use and consequence of masking strategies and the impact this has on well-being. Eight women were interviewed, and three major themes were identified. The themes outline the influence of gender expectations and social norms on the women’s experiences, the significance of diagnosis to their identity, and the influence of the medicalization of ASD. Participants shared experiences of feeling different and internalizing blame for this difference. The feeling of difference was a major contributor to the women’s positive or negative mental well-being. The process of diagnosis allowed participants to create and confirm their identity. Diagnosis also led to improvements in well-being, however, the findings also explore the complexity of labeling individuals with a disorder and the difficulties that arise from the construct of ‘functionality’ for those with Autism. The study also explores the temporal nature of ASD and the changing experiences of women as they mature. It is hoped this study promotes discussion and provides clinicians and those connected to ASD women with insights into the support ASD women require to live authentic lives.

Keywords: female autism, gender, masking, social constructionism

Procedia PDF Downloads 47
33 A Partially Accelerated Life Test Planning with Competing Risks and Linear Degradation Path under Tampered Failure Rate Model

Authors: Fariba Azizi, Firoozeh Haghighi, Viliam Makis

Abstract:

In this paper, we propose a method to model the relationship between failure time and degradation for a simple step stress test where underlying degradation path is linear and different causes of failure are possible. It is assumed that the intensity function depends only on the degradation value. No assumptions are made about the distribution of the failure times. A simple step-stress test is used to shorten failure time of products and a tampered failure rate (TFR) model is proposed to describe the effect of the changing stress on the intensities. We assume that some of the products that fail during the test have a cause of failure that is only known to belong to a certain subset of all possible failures. This case is known as masking. In the presence of masking, the maximum likelihood estimates (MLEs) of the model parameters are obtained through an expectation-maximization (EM) algorithm by treating the causes of failure as missing values. The effect of incomplete information on the estimation of parameters is studied through a Monte-Carlo simulation. Finally, a real example is analyzed to illustrate the application of the proposed methods.

Keywords: cause of failure, linear degradation path, reliability function, expectation-maximization algorithm, intensity, masked data

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32 Effect of Noise Reduction Algorithms on Temporal Splitting of Speech Signal to Improve Speech Perception for Binaural Hearing Aids

Authors: Rajani S. Pujar, Pandurangarao N. Kulkarni

Abstract:

Increased temporal masking affects the speech perception in persons with sensorineural hearing impairment especially under adverse listening conditions. This paper presents a cascaded scheme, which employs a noise reduction algorithm as well as temporal splitting of the speech signal. Earlier investigations have shown that by splitting the speech temporally and presenting alternate segments to the two ears help in reducing the effect of temporal masking. In this technique, the speech signal is processed by two fading functions, complementary to each other, and presented to left and right ears for binaural dichotic presentation. In the present study, half cosine signal is used as a fading function with crossover gain of 6 dB for the perceptual balance of loudness. Temporal splitting is combined with noise reduction algorithm to improve speech perception in the background noise. Two noise reduction schemes, namely spectral subtraction and Wiener filter are used. Listening tests were conducted on six normal-hearing subjects, with sensorineural loss simulated by adding broadband noise to the speech signal at different signal-to-noise ratios (∞, 3, 0, and -3 dB). Objective evaluation using PESQ was also carried out. The MOS score for VCV syllable /asha/ for SNR values of ∞, 3, 0, and -3 dB were 5, 4.46, 4.4 and 4.05 respectively, while the corresponding MOS scores for unprocessed speech were 5, 1.2, 0.9 and 0.65, indicating significant improvement in the perceived speech quality for the proposed scheme compared to the unprocessed speech.

Keywords: MOS, PESQ, spectral subtraction, temporal splitting, wiener filter

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31 Investigation of an Approach in Drug Delivery: Orally Fast Disintegrating Tablets

Authors: Tansel Comoglu

Abstract:

Orally fast disintegrating tablets (FDTs or ODTs) have become popular during the last decade, and manufacturing of ODTs is getting a rapidly growing area in the pharmaceutical industry. The concept of ODTs has emerged from the desire to provide patients with more conventional means of taking their medication. Drugs, that have satisfactory absorption from the oral mucosa or aimed for immediate therapeutic activity can be formulated in ODTs. After placing the ODT into the mouth, these tablets dissolve or disintegrate in the mouth usullay less than a minute, in the absence of additional water. Even though the ODT technology has taken an important path, as proved by a large group of commercial products on the drug market, there are so many problems to be solved in ODT formulations such as; formulation of hydrophobic drugs is stil a challenge, especially when the amount of drug is high. As these tablets dissolve or disintegrate in the mouth without the need of additional water, taste masking of active ingredients becomes essential in these systems because the drug is entirely released in the mouth. In ODT technology, coping with the taste of drugs is still a challenge. Resins or sweeteners or other techniques are also used in the formulation to aid taste-masking of the API. Another important factor to consider is whether they can be manufactured using conventional equipment and processes, as this will have a positive influence on manufacturing costs. Some products, however, may require a more costly, special unitdose packaging if the dosage form is fragile. In this overview, benefits, various formulation technologies, clinical studies and some future research trends of ODTs will be discussed.

Keywords: orally fast disintegrating tablets, benefits, formulation technologies, future research trends

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30 Fexofenadine Hydrochloride Orodispersisble Tablets: Formulation and in vitro/in vivo Evaluation in Healthy Human Volunteers

Authors: Soad Ali Yehia, Mohamed Shafik El-Ridi, Mina Ibrahim Tadros, Nolwa Gamal El-Sherif

Abstract:

Fexofenadine hydrochloride (FXD) is a slightly soluble, bitter-tasting, drug having an oral bioavailability of 35%. The maximum plasma concentration is reached 2.6 hours (Tmax) post-dose. The current work aimed to develop taste-masked FXD orodispersible tablets (ODTs) to increase extent of drug absorption and reduce Tmax. Taste masking was achieved via solid dispersion (SD) with chitosan (CS) or sodium alginate (ALG). FT-IR, DSC and XRD were performed to identify physicochemical interactions and FXD crystallinity. Taste-masked FXD-ODTs were developed via addition of superdisintegrants (crosscarmelose sodium or sodium starch glycolate, 5% and 10%, w/w) or sublimable agents (camphor, menthol or thymol; 10% and 20%, w/w) to FXD-SDs. ODTs were evaluated for weight variation, drug-content, friability, wetting time, disintegration time and drug release. Camphor-based (20%, w/w) FXD-ODT (F12) was optimized (F23) by incorporation of a more hydrophilic lubricant, sodium stearyl fumarate (Pruv®). The topography of the latter formula was examined via scanning electron microscopy (SEM). The in vivo estimation of FXD pharmacokinetics, relative to Allegra® tablets, was evaluated in healthy human volunteers. Based on the gustatory sensation test in healthy volunteers, FXD:CS (1:1) and FXD:ALG (1:0.5) SDs were selected. Taste-masked FXD-ODTs had appropriate physicochemical properties and showed short wetting and disintegration times. Drug release profiles of F23 and phenylalanine-containing Allegra® ODT were similar (f2 = 96) showing a complete release in two minutes. SEM micrographs revealed pores following camphor sublimation. Compared to Allegra® tablets, pharmacokinetic studies in healthy volunteers proved F23 ability to increase extent of FXD absorption (14%) and reduce Tmax to 1.83 h.

Keywords: fexofenadine hydrochloride, taste masking, chitosan, orodispersible

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29 Estimating the Life-Distribution Parameters of Weibull-Life PV Systems Utilizing Non-Parametric Analysis

Authors: Saleem Z. Ramadan

Abstract:

In this paper, a model is proposed to determine the life distribution parameters of the useful life region for the PV system utilizing a combination of non-parametric and linear regression analysis for the failure data of these systems. Results showed that this method is dependable for analyzing failure time data for such reliable systems when the data is scarce.

Keywords: masking, bathtub model, reliability, non-parametric analysis, useful life

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28 Perceptual Image Coding by Exploiting Internal Generative Mechanism

Authors: Kuo-Cheng Liu

Abstract:

In the perceptual image coding, the objective is to shape the coding distortion such that the amplitude of distortion does not exceed the error visibility threshold, or to remove perceptually redundant signals from the image. While most researches focus on color image coding, the perceptual-based quantizer developed for luminance signals are always directly applied to chrominance signals such that the color image compression methods are inefficient. In this paper, the internal generative mechanism is integrated into the design of a color image compression method. The internal generative mechanism working model based on the structure-based spatial masking is used to assess the subjective distortion visibility thresholds that are visually consistent to human eyes better. The estimation method of structure-based distortion visibility thresholds for color components is further presented in a locally adaptive way to design quantization process in the wavelet color image compression scheme. Since the lowest subband coefficient matrix of images in the wavelet domain preserves the local property of images in the spatial domain, the error visibility threshold inherent in each coefficient of the lowest subband for each color component is estimated by using the proposed spatial error visibility threshold assessment. The threshold inherent in each coefficient of other subbands for each color component is then estimated in a local adaptive fashion based on the distortion energy allocation. By considering that the error visibility thresholds are estimated using predicting and reconstructed signals of the color image, the coding scheme incorporated with locally adaptive perceptual color quantizer does not require side information. Experimental results show that the entropies of three color components obtained by using proposed IGM-based color image compression scheme are lower than that obtained by using the existing color image compression method at perceptually lossless visual quality.

Keywords: internal generative mechanism, structure-based spatial masking, visibility threshold, wavelet domain

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27 Effect of Classroom Acoustic Factors on Language and Cognition in Bilinguals and Children with Mild to Moderate Hearing Loss

Authors: Douglas MacCutcheon, Florian Pausch, Robert Ljung, Lorna Halliday, Stuart Rosen

Abstract:

Contemporary classrooms are increasingly inclusive of children with mild to moderate disabilities and children from different language backgrounds (bilinguals, multilinguals), but classroom environments and standards have not yet been adapted adequately to meet these challenges brought about by this inclusivity. Additionally, classrooms are becoming noisier as a learner-centered as opposed to teacher-centered teaching paradigm is adopted, which prioritizes group work and peer-to-peer learning. Challenging listening conditions with distracting sound sources and background noise are known to have potentially negative effects on children, particularly those that are prone to struggle with speech perception in noise. Therefore, this research investigates two groups vulnerable to these environmental effects, namely children with a mild to moderate hearing loss (MMHLs) and sequential bilinguals learning in their second language. In the MMHL study, this group was assessed on speech-in-noise perception, and a number of receptive language and cognitive measures (auditory working memory, auditory attention) and correlations were evaluated. Speech reception thresholds were found to be predictive of language and cognitive ability, and the nature of correlations is discussed. In the bilinguals study, sequential bilingual children’s listening comprehension, speech-in-noise perception, listening effort and release from masking was evaluated under a number of different ecologically valid acoustic scenarios in order to pinpoint the extent of the ‘native language benefit’ for Swedish children learning in English, their second language. Scene manipulations included target-to-distractor ratios and introducing spatially separated noise. This research will contribute to the body of findings from which educational institutions can draw when designing or adapting educational environments in inclusive schools.

Keywords: sequential bilinguals, classroom acoustics, mild to moderate hearing loss, speech-in-noise, release from masking

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26 Formulation, Preparation, and Evaluation of Coated Desloratadine Oral Disintegrating Tablets

Authors: Mohamed A. Etman, Mona G. Abd-Elnasser, Mohamed A. Shams-Eldin, Aly H. Nada

Abstract:

Orally disintegrating tablets (ODTs) are gaining importance as new drug delivery systems and emerged as one of the popular and widely accepted dosage forms, especially for the pediatric and geriatric patients. Their advantages such as administration without water, anywhere, anytime lead to their suitability to geriatric and pediatric patients. They are also suitable for the mentally ill, the bed-ridden and patients who do not have easy access to water. The benefits, in terms of patient compliance, rapid onset of action, increased bioavailability, and good stability make these tablets popular as a dosage form of choice in the current market. These dosage forms dissolve or disintegrate in the oral cavity within a matter of seconds without the need of water or chewing. Desloratadine is a tricyclic antihistaminic, which has a selective and peripheral H1-antagonist action. It is an antagonist at histamine H1 receptors, and an antagonist at all subtypes of the muscarinic acetylcholine receptor. Desloratadine is the major metabolite of loratadine. Twelve different placebos ODT were prepared (F1-F12) using different functional excipients. They were evaluated for their compressibility, hardness and disintegration time. All formulations were non sticky except four formulations; namely (F8, F9, F10, F11). All formulations were compressible with the exception of (F2). Variable disintegration times were found ranging between 20 and 120 seconds. It was found that (F12) showed the least disintegration time (20 secs) without showing any sticking which could be due to the use of high percentage of superdisintegrants. Desloratadine showed bitter taste when formulated as ODT without any treatment. Therefore, different techniques were tried in order to mask its bitter taste. Using Eudragit EPO resulted in complete masking of the bitter taste of the drug and increased the acceptability to volunteers. The compressible non sticky formulations (F1, F3, F4, F5, F6, F7 and F12) were subjected to further evaluation tests after addition of coated desloratadine, including weight uniformity, wetting time, and friability testing.. Fairly good weight uniformity values were observed in all the tested formulations. F12 exhibiting the shortest wetting time (14.7 seconds) and consequently the lowest (20 seconds) disintegration time. Dissolution profile showed that 100% desloratadine release was attained after only 2.5 minutes from the prepared ODT (F12) with dissolution efficiency of 95%.

Keywords: Desloratadine, orally disintegrating tablets (ODTs), formulations, taste masking

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25 The Role of Cognitive Control and Social Camouflage Associated with Social Anxiety Autism Spectrum Conditions

Authors: Siqing Guan, Fumiyo Oshima, Eiji Shimizu, Nozomi Tomita, Toru Takahashi, Hiroaki Kumano

Abstract:

Risk factors for social anxiety in autism spectrum conditions involve executive attention, emotion regulation, and thought regulation as processes of cognitive dysregulation. Social camouflaging behaviors as strategies used to mask and/or compensate for autism characteristics during social interactions in autism spectrum conditions have also been emphasized. However, the role of cognitive dysregulation and social camouflaging related to social anxiety in autism spectrum conditions has not been clarified. Whether these factors are specific to social anxiety in autism spectrum conditions or common to social anxiety independent of autism spectrum conditions needs to be clarified. Here, we explored risk factors specific to social anxiety in autism spectrum conditions and general risk factors for social anxiety independent of autism spectrum conditions. From the Japanese participants in early adulthood (age=18~39) of the online survey in Japan, those who exceeded the Japanese version Autism-Spectrum Quotient cutoff (33 points or more )were divided into the autism spectrum conditions group (ASC; N=255, mean age=32.08, SD age=5.16)and those who did not exceed the cutoff were divided into the non-autism spectrum conditions group (Non-ASC; N=255, mean age=31.70, SD age=5.09). Using the Japanese versions of the Social Phobia Scale, the Social Interaction Anxiety Scale, and the Short Fear of Negative Evaluation Scale, a composite score for social anxiety was calculated using a method of principal. We also measured emotional control difficulties using the Difficulties in Emotion Regulation Scale, executive attention using the Effortful Control Scale for Adults, rumination using the Rumination-Reflection Questionnaire, and worry using the Penn State Worry Questionnaire. This study was passed through the review of the Ethics Committee. No conflicts of interest. Multiple regression analysis with forced entry method was used to predict social anxiety in the ASC and non-ASC groups separately, based on executive attention, emotion dysregulation, worry, rumination, and social camouflage. In the ASC group, emotion dysregulation (β=.277, p<.001), worry (β=.162, p<.05), assimilation (β=.308, p<.001) and masking (β=.275, p<.001) were significant predictors of social anxiety (F (7,247) = 45.791, p <.001, R2=.565). In the non-ASC groups,emotion dysregulation (β=.171, p<.05), worry (β=.344,p <.001), assimilation (β=.366,p <.001) and executive attention (β=-.132,p <.05) were significant predictors of social anxiety (F (7,207) =47.333, p <.001, R2=.615).The findings suggest that masking was shown to be a risk factor for social anxiety specific to autism spectrum conditions, while emotion dysregulation, worry, and assimilation were shown to be common risk factors for social anxiety, regardless of autism spectrum conditions. In addition, executive attention is a risk factor for social anxiety without autism spectrum conditions.

Keywords: autism spectrum, cognitive control, social anxiety, social camouflaging

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24 Social Contact Patterns among School-Age Children in Taiwan

Authors: Dih Ling Luh, Zhi Shih You, Szu Chieh Chen

Abstract:

Social contact patterns among school-age children play an important role in the epidemiology of infectious disease. Since many of the greatest threats to human health are spread by direct person-to-person contact, understanding the spread of respiratory pathogens and patterns of human interactions are public health priorities. This study used social contact diaries to compare the number of contacts per day per participant across different flu/non-flu seasons and weekend/weekday. We also present contact properties such as sex, age, masking, setting, frequency, duration, and contact types among school-age children (grades 7–8). The sample size with pair-wise comparisons for the seasons (flu/non-flu) and stratification by location were 54 and 83, respectively. There was no difference in the number of contacts during the flu and non-flu seasons, with averages of 16.3 (S.D. = 12.9) and 14.6 (S.D. = 9.5) people, respectively. Weekdays were associated with 23% and 28% more contacts than weekend days during the non-flu and flu seasons, respectively (p < 0.001) (Wilcoxon signed-rank test).

Keywords: contact patterns, behavior, influenza, social mixing

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23 Vibration Propagation in Structures Through Structural Intensity Analysis

Authors: Takhchi Jamal, Ouisse Morvan, Sadoulet-Reboul Emeline, Bouhaddi Noureddine, Gagliardini Laurent, Bornet Frederic, Lakrad Faouzi

Abstract:

Structural intensity is a technique that can be used to indicate both the magnitude and direction of power flow through a structure from the excitation source to the dissipation sink. However, current analysis is limited to the low frequency range. At medium and high frequencies, a rotational component appear in the field, masking the energy flow and make its understanding difficult or impossible. The objective of this work is to implement a methodology to filter out the rotational components of the structural intensity field in order to fully understand the energy flow in complex structures. The approach is based on the Helmholtz decomposition. It allows to decompose the structural intensity field into rotational, irrotational, and harmonic components. Only the irrotational component is needed to describe the net power flow from a source to a dissipative zone in the structure. The methodology has been applied on academic structures, and it allows a good analysis of the energy transfer paths.

Keywords: structural intensity, power flow, helmholt decomposition, irrotational intensity

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22 Solvent Extraction, Spectrophotometric Determination of Antimony(III) from Real Samples and Synthetic Mixtures Using O-Methylphenyl Thiourea as a Sensitive Reagent

Authors: Shashikant R. Kuchekar, Shivaji D. Pulate, Vishwas B. Gaikwad

Abstract:

A simple and selective method is developed for solvent extraction spectrophotometric determination of antimony(III) using O-Methylphenyl Thiourea (OMPT) as a sensitive chromogenic chelating agent. The basis of proposed method is formation of antimony(III)-OMPT complex was extracted with 0.0025 M OMPT in chloroform from aqueous solution of antimony(III) in 1.0 M perchloric acid. The absorbance of this complex was measured at 297 nm against reagent blank. Beer’s law was obeyed up to 15µg mL-1 of antimony(III). The Molar absorptivity and Sandell’s sensitivity of the antimony(III)-OMPT complex in chloroform are 16.6730 × 103 L mol-1 cm-1 and 0.00730282 µg cm-2 respectively. The stoichiometry of antimony(III)-OMPT complex was established from slope ratio method, mole ratio method and Job’s continuous variation method was 1:2. The complex was stable for more than 48 h. The interfering effect of various foreign ions was studied and suitable masking agents are used wherever necessary to enhance selectivity of the method. The proposed method is successfully applied for determination of antimony(III) from real samples alloy and synthetic mixtures. Repetition of the method was checked by finding relative standard deviation (RSD) for 10 determinations which was 0.42%.

Keywords: solvent extraction, antimony, spectrophotometry, real sample analysis

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21 Analysis of Two Phase Hydrodynamics in a Column Flotation by Particle Image Velocimetry

Authors: Balraju Vadlakonda, Narasimha Mangadoddy

Abstract:

The hydrodynamic behavior in a laboratory column flotation was analyzed using particle image velocimetry. For complete characterization of column flotation, it is necessary to determine the flow velocity induced by bubbles in the liquid phase, the bubble velocity and bubble characteristics:diameter,shape and bubble size distribution. An experimental procedure for analyzing simultaneous, phase-separated velocity measurements in two-phase flows was introduced. The non-invasive PIV technique has used to quantify the instantaneous flow field, as well as the time averaged flow patterns in selected planes of the column. Using the novel particle velocimetry (PIV) technique by the combination of fluorescent tracer particles, shadowgraphy and digital phase separation with masking technique measured the bubble velocity as well as the Reynolds stresses in the column. Axial and radial mean velocities as well as fluctuating components were determined for both phases by averaging the sufficient number of double images. Bubble size distribution was cross validated with high speed video camera. Average turbulent kinetic energy of bubble were analyzed. Different air flow rates were considered in the experiments.

Keywords: particle image velocimetry (PIV), bubble velocity, bubble diameter, turbulent kinetic energy

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20 Design and Fabrication of an Electrostatically Actuated Parallel-Plate Mirror by 3D-Printer

Authors: J. Mizuno, S. Takahashi

Abstract:

In this paper, design and fabrication of an actuated parallel-plate mirror based on a 3D-printer is described. The mirror and electrode layers are fabricated separately and assembled thereafter. The alignment is performed by dowel pin-hole pairs fabricated on the respective layers. The electrodes are formed on the surface of the electrode layer by Au ion sputtering using a suitable mask, which is also fabricated by a 3D-printer.For grounding the mirror layer, except the contact area with the electrode paths, all the surface is Au ion sputtered. 3D-printers are widely used for creating 3D models or mock-ups. The authors have recently proposed that these models can perform electromechanical functions such as actuators by suitably masking them followed by metallization process. Since the smallest possible fabrication size is in the order of sub-millimeters, these electromechanical devices are named by the authors as SMEMS (Sub-Milli Electro-Mechanical Systems) devices. The proposed mirror described in this paper which consists of parallel-plate electrostatic actuators is also one type of SMEMS devices. In addition, SMEMS is totally environment-clean compared to MEMS (Micro Electro-Mechanical Systems) fabrication processes because any hazardous chemicals or gases are utilized.

Keywords: MEMS, parallel-plate mirror, SMEMS, 3D-printer

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19 Implementation of Real-Time Multiple Sound Source Localization and Separation

Authors: Jeng-Shin Sheu, Qi-Xun Zheng

Abstract:

This paper mainly discusses a method of separating speech when using a microphone array without knowing the number and direction of sound sources. In recent years, there have been many studies on the method of separating signals by using masking, but most of the separation methods must be operated under the condition of a known number of sound sources. Such methods cannot be used for real-time applications. In our method, this paper uses Circular-Integrated-Cross-Spectrum to estimate the statistical histogram distribution of the direction of arrival (DOA) to obtain the number of sound sources and sound in the mixed-signal Source direction. In calculating the relevant parameters of the ring integrated cross-spectrum, the phase (Phase of the Cross-Power Spectrum) and phase rotation factors (Phase Rotation Factors) calculated by the cross power spectrum of each microphone pair are used. In the part of separating speech, it uses the DOA weighting and shielding separation method to calculate the sound source direction (DOA) according to each T-F unit (time-frequency point). The weight corresponding to each T-F unit can be used to strengthen the intensity of each sound source from the T-F unit and reduce the influence of the remaining sound sources, thereby achieving voice separation.

Keywords: real-time, spectrum analysis, sound source localization, sound source separation

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18 Enhancement of Underwater Haze Image with Edge Reveal Using Pixel Normalization

Authors: M. Dhana Lakshmi, S. Sakthivel Murugan

Abstract:

As light passes from source to observer in the water medium, it is scattered by the suspended particulate matter. This scattering effect will plague the captured images with non-uniform illumination, blurring details, halo artefacts, weak edges, etc. To overcome this, pixel normalization with an Amended Unsharp Mask (AUM) filter is proposed to enhance the degraded image. To validate the robustness of the proposed technique irrespective of atmospheric light, the considered datasets are collected on dual locations. For those images, the maxima and minima pixel intensity value is computed and normalized; then the AUM filter is applied to strengthen the blurred edges. Finally, the enhanced image is obtained with good illumination and contrast. Thus, the proposed technique removes the effect of scattering called de-hazing and restores the perceptual information with enhanced edge detail. Both qualitative and quantitative analyses are done on considering the standard non-reference metric called underwater image sharpness measure (UISM), and underwater image quality measure (UIQM) is used to measure color, sharpness, and contrast for both of the location images. It is observed that the proposed technique has shown overwhelming performance compared to other deep-based enhancement networks and traditional techniques in an adaptive manner.

Keywords: underwater drone imagery, pixel normalization, thresholding, masking, unsharp mask filter

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17 Constructions of Linear and Robust Codes Based on Wavelet Decompositions

Authors: Alla Levina, Sergey Taranov

Abstract:

The classical approach to the providing noise immunity and integrity of information that process in computing devices and communication channels is to use linear codes. Linear codes have fast and efficient algorithms of encoding and decoding information, but this codes concentrate their detect and correct abilities in certain error configurations. To protect against any configuration of errors at predetermined probability can robust codes. This is accomplished by the use of perfect nonlinear and almost perfect nonlinear functions to calculate the code redundancy. The paper presents the error-correcting coding scheme using biorthogonal wavelet transform. Wavelet transform applied in various fields of science. Some of the wavelet applications are cleaning of signal from noise, data compression, spectral analysis of the signal components. The article suggests methods for constructing linear codes based on wavelet decomposition. For developed constructions we build generator and check matrix that contain the scaling function coefficients of wavelet. Based on linear wavelet codes we develop robust codes that provide uniform protection against all errors. In article we propose two constructions of robust code. The first class of robust code is based on multiplicative inverse in finite field. In the second robust code construction the redundancy part is a cube of information part. Also, this paper investigates the characteristics of proposed robust and linear codes.

Keywords: robust code, linear code, wavelet decomposition, scaling function, error masking probability

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16 Esthetic Rehabilitation of White and Brown Spot Lesions with Ceramic Veneers: A Clinical Report

Authors: Rania E. Ramadan

Abstract:

Dental esthetics is subjective, can be reported by the dentist and not noticed by the patient. However, if there is any imperfection seen by both the dentist and the patient, it is considered as an unesthetic like white and/or brown spot lesions. Many patients nowadays have been concerned about dental esthetics. Esthetic rehabilitation of anterior teeth and even maxillary premolars aid a lot in patients’ satisfaction of their smile consequently, gaining positive psychological impact for the patients. Many cases need esthetic rehabilitation such as diastema closure, spaced teeth and masking discolored teeth. Dental fluorosis and enamel hypo calcification can be presented as white and/or brown spot lesions. There are many treatment options for the management of these spotted teeth. Treatment options range from bleaching, microabrasion, direct composite restorations, porcelain veneers, and complete coverage crowns. The selection of certain options depends on many factors: the patient’s age, socioeconomic status and the severity of the lesion. In this clinical report, a 22-year-old male patient has been presented to the Department of Prosthodontics in Alexandria University, Egypt. His chief complaint was, “I was unpleased by white and brown spots in my teeth and I want to close the space between the two maxillary central.” Upon medical history, clinical examination, diagnostic photographs, and digital smile design by Exocad software, lithium disilicate veneers were chosen as the treatment of choice in maxillary anterior and first premolars.

Keywords: flourosis, ceramic veneers, case report, diastema closure

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15 Development of Antimicrobial Properties Nutraceuticals: Gummy Candies with Addition of Bovine Colostrum, Essential Oils and Probiotics

Authors: E. Bartkiene, M. Ruzauskas, V. Lele, P. Zavistanaviciute, J. Bernatoniene, V. Jakstas, L. Ivanauskas, D. Zadeike, D. Klupsaite, P. Viskelis, J. Bendoraitiene, V. Navikaite-Snipaitiene, G. Juodeikiene

Abstract:

In this study, antimicrobial nutraceuticals; gummy candies (GC) from bovine colostrum (BC), essential oils (EOs), probiotic lactic acid bacteria (PLAB), and their combinations, were developed. For antimicrobial GC preparation, heteropolysaccharide (agar) was used. The antimicrobial properties of EOs (Eugenia caryophyllata, Thymus vulgaris, Citrus reticulata L., Citrus paradisi L.), BC, L. paracasei LUHS244, L. plantarum LUHS135, and their combinations against pathogenic bacteria strains (Streptococcus mutans, Enterococcus faecalis, Staphylococcus aureus, Salmonella enterica, Escherichia coli, Proteus mirabilis, and Pseudomonas aeruginosa) were evaluated. The highest antimicrobial properties by EO’s (Eugenia caryophyllata and Thymus vulgaris) were established. The optimal ingredients composition for antimicrobial GC preparation was established, which incorporate the BC fermented with L. paracasei LUHS244 in combination with Thymus vulgaris or Eugenia caryophyllata. These ingredients showed high inhibition properties of all tested pathogenic strains (except Pseudomonas aeruginosa). Antimicrobial GC formula consisting of thyme EO (up to 0.2%) and fermented BC (up to 3%), and for taste masking, mandarin or grapefruit EOs (up to 0.2%) was used. Developed GC high overall acceptability and antimicrobial properties, thus, antimicrobial GC could be a preferred form of nutraceuticals. This study was fulfilled with the support of the LSMU-KTU joint project.

Keywords: antimicrobial activity, bovine colostrum, essential oil, gummy candy, probiotic

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14 Immune Complex Components Act as Agents in Relapsing Fever Borrelia Mediated Rosette Formation

Authors: Mukunda Upreti, Jill Storry, Rafael Björk, Emilie Louvet, Johan Normark, Sven Bergström

Abstract:

Borrelia duttonii and most other relapsing fever species are Gram-negative bacteria which cause a blood borne infection characterized by the binding of bacterium to erythrocytes. The bacteria associate with two or more erythrocytes to form clusters of cells into rosettes. Rosetting is a major virulence factor and the mechanism is believed to facilitate persistence of bacteria in the circulatory system and the avoidance of host immune cells through masking or steric hindrance effects. However, the molecular mechanisms of rosette formation are still poorly understood. This study aims at determining the molecules involved in the rosette formation phenomenon. Fractionated serum, using different affinity purification methods, was investigated as a rosetting agent and IgG and at least one other serum components were needed for rosettes to form. An IgG titration curve demonstrated that IgG alone is not enough to restore rosette formation level to the level whole serum gives. IgG hydrolysis by IdeS ( Immunoglobulin G-degrading enzyme of Streptococcus pyogenes) and deglycosylation using N-Glycanase proved that the whole IgG molecule regardless of saccharide moieties is critical for Borrelia induced rosetting. Complement components C3 and C4 were also important serum molecules necessary to maintain optimum rosetting rates. The deactivation of complement network and serum depletion with C3 and C4 significantly reduced the rosette formation rate. The dependency of IgG and complement components also implied involvement of the complement receptor (CR1). Rosette formation test with Knops null RBC and sCR1 confirmed that CR1 is also part of Borrelia induced rosette formation.

Keywords: complement components C3 and C4, complement receptor 1, Immunoglobulin G, Knops null, Rosetting

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13 An Investigation of the Use of Visible Spectrophotometric Analysis of Lead in an Herbal Tea Supplement

Authors: Salve Alessandria Alcantara, John Armand E. Aquino, Ma. Veronica Aranda, Nikki Francine Balde, Angeli Therese F. Cruz, Elise Danielle Garcia, Antonie Kyna Lim, Divina Gracia Lucero, Nikolai Thadeus Mappatao, Maylan N. Ocat, Jamille Dyanne L. Pajarillo, Jane Mierial A. Pesigan, Grace Kristin Viva, Jasmine Arielle C. Yap, Kathleen Michelle T. Yu, Joanna J. Orejola, Joanna V. Toralba

Abstract:

Lead is a neurotoxic metallic element that is slowly accumulated in bones and tissues especially if present in products taken in a regular basis such as herbal tea supplements. Although sensitive analytical instruments are already available, the USP limit test for lead is still widely used. However, because of its serious shortcomings, Lang Lang and his colleagues developed a spectrophotometric method for determination of lead in all types of samples. This method was the one adapted in this study. The actual procedure performed was divided into three parts: digestion, extraction and analysis. For digestion, HNO3 and CH3COOH were used. Afterwards, masking agents, 0.003% and 0.001% dithizone in CHCl3 were added and used for the extraction. For the analysis, standard addition method and colorimetry were performed. This was done in triplicates under two conditions. The 1st condition, using 25µg/mL of standard, resulted to very low absorbances with an r2 of 0.551. This led to the use of a higher concentration, 1mg/mL, for condition 2. Precipitation of lead cyanide was observed and the absorbance readings were relatively higher but between 0.15-0.25, resulting to a very low r2 of 0.429. LOQ and LOD were not computed due to the limitations of the Milton-Roy Spectrophotometer. The method performed has a shorter digestion time, and used less but more accessible reagents. However, the optimum ratio of dithizone-lead complex must be observed in order to obtain reliable results while exploring other concentration of standards.

Keywords: herbal tea supplement, lead-dithizone complex, standard addition, visible spectroscopy

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12 Exploring Bidirectional Encoder Representations from the Transformers’ Capabilities to Detect English Preposition Errors

Authors: Dylan Elliott, Katya Pertsova

Abstract:

Preposition errors are some of the most common errors created by L2 speakers. In addition, improving error correction and detection methods remains an open issue in the realm of Natural Language Processing (NLP). This research investigates whether the bidirectional encoder representations from the transformers model (BERT) have the potential to correct preposition errors accurately enough to be useful in error correction software. This research finds that BERT performs strongly when the scope of its error correction is limited to preposition choice. The researchers used an open-source BERT model and over three hundred thousand edited sentences from Wikipedia, tagged for part of speech, where only a preposition edit had occurred. To test BERT’s ability to detect errors, a technique known as multi-level masking was used to generate suggestions based on sentence context for every prepositional environment in the test data. These suggestions were compared with the original errors in the data and their known corrections to evaluate BERT’s performance. The suggestions were further analyzed to determine if BERT more often agreed with the judgements of the Wikipedia editors. Both the untrained and fined-tuned models were compared. Finetuning led to a greater rate of error-detection which significantly improved recall, but lowered precision due to an increase in false positives or falsely flagged errors. However, in most cases, these false positives were not errors in preposition usage but merely cases where more than one preposition was possible. Furthermore, when BERT correctly identified an error, the model largely agreed with the Wikipedia editors, suggesting that BERT’s ability to detect misused prepositions is better than previously believed. To evaluate to what extent BERT’s false positives were grammatical suggestions, we plan to do a further crowd-sourcing study to test the grammaticality of BERT’s suggested sentence corrections against native speakers’ judgments.

Keywords: BERT, grammatical error correction, preposition error detection, prepositions

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11 Uncertainty Evaluation of Erosion Volume Measurement Using Coordinate Measuring Machine

Authors: Mohamed Dhouibi, Bogdan Stirbu, Chabotier André, Marc Pirlot

Abstract:

Internal barrel wear is a major factor affecting the performance of small caliber guns in their different life phases. Wear analysis is, therefore, a very important process for understanding how wear occurs, where it takes place, and how it spreads with the aim on improving the accuracy and effectiveness of small caliber weapons. This paper discusses the measurement and analysis of combustion chamber wear for a small-caliber gun using a Coordinate Measuring Machine (CMM). Initially, two different NATO small caliber guns: 5.56x45mm and 7.62x51mm, are considered. A Micura Zeiss Coordinate Measuring Machine (CMM) equipped with the VAST XTR gold high-end sensor is used to measure the inner profile of the two guns every 300-shot cycle. The CMM parameters, such us (i) the measuring force, (ii) the measured points, (iii) the time of masking, and (iv) the scanning velocity, are investigated. In order to ensure minimum measurement error, a statistical analysis is adopted to select the reliable CMM parameters combination. Next, two measurement strategies are developed to capture the shape and the volume of each gun chamber. Thus, a task-specific measurement uncertainty (TSMU) analysis is carried out for each measurement plan. Different approaches of TSMU evaluation have been proposed in the literature. This paper discusses two different techniques. The first is the substitution method described in ISO 15530 part 3. This approach is based on the use of calibrated workpieces with similar shape and size as the measured part. The second is the Monte Carlo simulation method presented in ISO 15530 part 4. Uncertainty evaluation software (UES), also known as the Virtual Coordinate Measuring Machine (VCMM), is utilized in this technique to perform a point-by-point simulation of the measurements. To conclude, a comparison between both approaches is performed. Finally, the results of the measurements are verified through calibrated gauges of several dimensions specially designed for the two barrels. On this basis, an experimental database is developed for further analysis aiming to quantify the relationship between the volume of wear and the muzzle velocity of small caliber guns.

Keywords: coordinate measuring machine, measurement uncertainty, erosion and wear volume, small caliber guns

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10 Intellectual Property Rights Reforms and the Quality of Exported Goods

Authors: Gideon Ndubuisi

Abstract:

It is widely acknowledged that the quality of a country’s export matters more decisively than the quantity it exports. Hence, understanding the drivers of exported goods’ quality is a relevant policy question. Among other things, product quality upgrading is a considerable cost uncertainty venture that can be undertaken by an entrepreneur. Once a product is successfully upgraded, however, others can imitate the product, and hence, the returns to the pioneer entrepreneur are socialized. Along with this line, a government policy such as intellectual property rights (IPRs) protection which lessens the non-appropriability problem and incentivizes cost discovery investments becomes both a panacea in addressing the market failure and a sine qua non for an entrepreneur to engage in product quality upgrading. In addendum, product quality upgrading involves complex tasks which often require a lot of knowledge and technology sharing beyond the bounds of the firm thereby creating rooms for knowledge spillovers and imitations. Without an institution that protects upstream suppliers of knowledge and technology, technology masking occurs which bids up marginal production cost and product quality fall. Despite these clear associations between IPRs and product quality upgrading, the surging literature on the drivers of the quality of exported goods has proceeded almost in isolation of IPRs protection as a determinant. Consequently, the current study uses a difference-in-difference method to evaluate the effects of IPRs reforms on the quality of exported goods in 16 developing countries over the sample periods of 1984-2000. The study finds weak evidence that IPRs reforms increase the quality of all exported goods. When the industries are sorted into high and low-patent sensitive industries, however, we find strong indicative evidence that IPRs reform increases the quality of exported goods in high-patent sensitive sectors both in absolute terms and relative to the low-patent sensitive sectors in the post-reform period. We also obtain strong indicative evidence that it brought the quality of exported goods in the high-patent sensitive sectors closer to the quality frontier. Accounting for time-duration effects, these observed effects grow over time. The results are also largely consistent when we consider the sophistication and complexity of exported goods rather than just quality upgrades.

Keywords: exports, export quality, export sophistication, intellectual property rights

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9 An Infinite Mixture Model for Modelling Stutter Ratio in Forensic Data Analysis

Authors: M. A. C. S. Sampath Fernando, James M. Curran, Renate Meyer

Abstract:

Forensic DNA analysis has received much attention over the last three decades, due to its incredible usefulness in human identification. The statistical interpretation of DNA evidence is recognised as one of the most mature fields in forensic science. Peak heights in an Electropherogram (EPG) are approximately proportional to the amount of template DNA in the original sample being tested. A stutter is a minor peak in an EPG, which is not masking as an allele of a potential contributor, and considered as an artefact that is presumed to be arisen due to miscopying or slippage during the PCR. Stutter peaks are mostly analysed in terms of stutter ratio that is calculated relative to the corresponding parent allele height. Analysis of mixture profiles has always been problematic in evidence interpretation, especially with the presence of PCR artefacts like stutters. Unlike binary and semi-continuous models; continuous models assign a probability (as a continuous weight) for each possible genotype combination, and significantly enhances the use of continuous peak height information resulting in more efficient reliable interpretations. Therefore, the presence of a sound methodology to distinguish between stutters and real alleles is essential for the accuracy of the interpretation. Sensibly, any such method has to be able to focus on modelling stutter peaks. Bayesian nonparametric methods provide increased flexibility in applied statistical modelling. Mixture models are frequently employed as fundamental data analysis tools in clustering and classification of data and assume unidentified heterogeneous sources for data. In model-based clustering, each unknown source is reflected by a cluster, and the clusters are modelled using parametric models. Specifying the number of components in finite mixture models, however, is practically difficult even though the calculations are relatively simple. Infinite mixture models, in contrast, do not require the user to specify the number of components. Instead, a Dirichlet process, which is an infinite-dimensional generalization of the Dirichlet distribution, is used to deal with the problem of a number of components. Chinese restaurant process (CRP), Stick-breaking process and Pólya urn scheme are frequently used as Dirichlet priors in Bayesian mixture models. In this study, we illustrate an infinite mixture of simple linear regression models for modelling stutter ratio and introduce some modifications to overcome weaknesses associated with CRP.

Keywords: Chinese restaurant process, Dirichlet prior, infinite mixture model, PCR stutter

Procedia PDF Downloads 263