Search results for: haematology values
5145 Expectations of Unvaccinated Health Workers in Greece and the Question of Trust: A Qualitative Study of Vaccine Hesitancy
Authors: Sideri Katerina, Chanania Eleni
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The reasons why people remain unvaccinated, especially health workers, are complex. In Greece, 2 percent of health workers (around 7,000) remain unvaccinated, despite the fact that for this group of people vaccination against COVID-19 is mandatory. In April 2022, the Greek health minister repeated that unvaccinated health care workers will remain suspended from their jobs ‘for as long as the pandemic lasts,’ explaining that the suspension of the workers in question was ‘entirely their choice’ and that health professionals who do not believe in vaccines ‘do not believe in their own science.’ Although policy circles around the world often link vaccine hesitancy to ignorance of science or misinformation, various recently published qualitative studies show that vaccine hesitancy is the result of a combination of factors, which include distrust towards elites and the system of innovation and distrust towards government. In a similar spirit, some commentators warn that labeling hesitancy as “anti-science” is bad politics. In this paper, we worked within the tradition of STS taking the view that people draw upon personal associations to enact and express civic concern with an issue, the enactment of public concern involves the articulation of threats to actors’ way of life, personal values, relationships, lived experiences, broader societal values and institutional structures. To this effect, we have conducted 27 in depth interviews with unvaccinated Greek health workers and we are in the process of conducting 20 more interviews. We have so far found that rather than a question of believing in ‘facts’ vaccine hesitancy reflects deep distrust towards those charged with the making of decisions and pharmaceutical companies and that emotions (rather than rational thinking) play a crucial role in the formation of attitudes and the making of decisions. We need to dig deeper so as to understand the causes of distrust towards technical government and the ways in which public(s) conceive of and want to be part in the politics of innovation. We particularly address the question of the effectiveness of mandatory vaccination of health workers and whether such top-down regulatory measures further polarize society, to finally discuss alternative regulatory approaches and governance structures.Keywords: vaccine hesitancy, innovation, trust in vaccines, sociology of vaccines, attitude drivers towards scientific information, governance
Procedia PDF Downloads 745144 Zooming into the Leadership Behaviours Desired by the 21st Century Workforce: Introduction of the Research Theory and Methods
Authors: Anita Bela, Marta Juhasz
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Adapting to the always-changing environment comes with complex determinants. The authors are zooming into one aspect only when the current workforce comes with obstacles by being less keen to stay engaged, even short or mid-term, resulting in additional challenges impacting the business performance. Seeing these occurring in practice made the researchers eager to gain a better understanding of the reasons behind. The paper aims to provide an overview of the theoretical background and research methods planned for the different stages of the research. The theoretical part takes the leadership behaviors under lens while the focus is on finding ways to attract and retain those who prefer working under more flexible employment conditions (e.g. contractor, contingent worker, etc.). These are considered as the organizational values and along with the power of people management are having their engaging relevance. The organizational culture (visible or invisible level) is clearly the mirror of the set of shared values guiding all members of the companies towards acceptable behavior. The applied research method, inductive reasoning was selected since the focus and questions raised in this research are results of specific observations made on the employees (various employment types) and leaders of start-ups and corporates. By comparing the similarities and differences, the researchers are hoping to prove the readiness and agility of the start-up culture for the desired leadership behaviours of the current and future workforce against the corporate culture. While exploring the preferences and engaging factors of the 21st-century workforce the data gathering would happen through website analysis – using ATLAS.ti qualitative software – followed by interview sessions where demographics will be collected and preferred leadership behaviors - using the Critical Incident Technique. Moreover, a short engagement survey will be administered to understand the linkage between the organizational culture type and engagement level. To conclude, after gaining theoretical understanding, we will zoom back to the employees to reveal the behaviors to be followed to achieve engagement in an environment where nothing is stable and where the companies always must keep their agile eyes and reactions vivid.Keywords: leadership behaviours, organizational culture, qualitative analysis, workforce engagement
Procedia PDF Downloads 1165143 GPU-Based Back-Projection of Synthetic Aperture Radar (SAR) Data onto 3D Reference Voxels
Authors: Joshua Buli, David Pietrowski, Samuel Britton
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Processing SAR data usually requires constraints in extent in the Fourier domain as well as approximations and interpolations onto a planar surface to form an exploitable image. This results in a potential loss of data requires several interpolative techniques, and restricts visualization to two-dimensional plane imagery. The data can be interpolated into a ground plane projection, with or without terrain as a component, all to better view SAR data in an image domain comparable to what a human would view, to ease interpretation. An alternate but computationally heavy method to make use of more of the data is the basis of this research. Pre-processing of the SAR data is completed first (matched-filtering, motion compensation, etc.), the data is then range compressed, and lastly, the contribution from each pulse is determined for each specific point in space by searching the time history data for the reflectivity values for each pulse summed over the entire collection. This results in a per-3D-point reflectivity using the entire collection domain. New advances in GPU processing have finally allowed this rapid projection of acquired SAR data onto any desired reference surface (called backprojection). Mathematically, the computations are fast and easy to implement, despite limitations in SAR phase history data size and 3D-point cloud size. Backprojection processing algorithms are embarrassingly parallel since each 3D point in the scene has the same reflectivity calculation applied for all pulses, independent of all other 3D points and pulse data under consideration. Therefore, given the simplicity of the single backprojection calculation, the work can be spread across thousands of GPU threads allowing for accurate reflectivity representation of a scene. Furthermore, because reflectivity values are associated with individual three-dimensional points, a plane is no longer the sole permissible mapping base; a digital elevation model or even a cloud of points (collected from any sensor capable of measuring ground topography) can be used as a basis for the backprojection technique. This technique minimizes any interpolations and modifications of the raw data, maintaining maximum data integrity. This innovative processing will allow for SAR data to be rapidly brought into a common reference frame for immediate exploitation and data fusion with other three-dimensional data and representations.Keywords: backprojection, data fusion, exploitation, three-dimensional, visualization
Procedia PDF Downloads 865142 Control of Photovoltaic System Interfacing Grid
Authors: Zerzouri Nora
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In this paper, author presented the generalities of a photovoltaic system study and simulation. Author inserted the DC-DC converter to raise the voltage level and improve the operation of the PV panel by continuing the operating point at maximum power by using the Perturb and Observe technique (P&O). The connection to the network is made by inserting a three-phase voltage inverter allowing synchronization with the network the inverter is controlled by a PWM control. The simulation results allow the author to visualize the operation of the different components of the system, as well as the behavior of the system during the variation of meteorological values.Keywords: photovoltaic generator PV, boost converter, P&O MPPT, PWM inverter, three phase grid
Procedia PDF Downloads 1195141 Acoustic Emission Monitoring of Surface Roughness in Ultra High Precision Grinding of Borosilicate-Crown Glass
Authors: Goodness Onwuka, Khaled Abou-El-Hossein
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The increase in the demand for precision optics, coupled with the absence of much research output in the ultra high precision grinding of precision optics as compared to the ultrahigh precision diamond turning of optical metals has fostered the need for more research in the ultra high precision grinding of an optical lens. Furthermore, the increase in the stringent demands for nanometric surface finishes through lapping, polishing and grinding processes necessary for the use of borosilicate-crown glass in the automotive and optics industries has created the demand to effectively monitor the surface roughness during the production process. Acoustic emission phenomenon has been proven as useful monitoring technique in several manufacturing processes ranging from monitoring of bearing production to tool wear estimation. This paper introduces a rare and unique approach with the application of acoustic emission technique to monitor the surface roughness of borosilicate-crown glass during an ultra high precision grinding process. This research was carried out on a 4-axes Nanoform 250 ultrahigh precision lathe machine using an ultra high precision grinding spindle to machine the flat surface of the borosilicate-crown glass with the tip of the grinding wheel. A careful selection of parameters and design of experiment was implemented using Box-Behnken method to vary the wheel speed, feed rate and depth of cut at three levels with a 3-center point design. Furthermore, the average surface roughness was measured using Taylor Hobson PGI Dimension XL optical profilometer, and an acoustic emission data acquisition device from National Instruments was utilized to acquire the signals while the data acquisition codes were designed with National Instrument LabVIEW software for acquisition at a sampling rate of 2 million samples per second. The results show that the raw and root mean square amplitude values of the acoustic signals increased with a corresponding increase in the measured average surface roughness values for the different parameter combinations. Therefore, this research concludes that acoustic emission monitoring technique is a potential technique for monitoring the surface roughness in the ultra high precision grinding of borosilicate-crown glass.Keywords: acoustic emission, borosilicate-crown glass, surface roughness, ultra high precision grinding
Procedia PDF Downloads 2915140 Classifying and Predicting Efficiencies Using Interval DEA Grid Setting
Authors: Yiannis G. Smirlis
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The classification and the prediction of efficiencies in Data Envelopment Analysis (DEA) is an important issue, especially in large scale problems or when new units frequently enter the under-assessment set. In this paper, we contribute to the subject by proposing a grid structure based on interval segmentations of the range of values for the inputs and outputs. Such intervals combined, define hyper-rectangles that partition the space of the problem. This structure, exploited by Interval DEA models and a dominance relation, acts as a DEA pre-processor, enabling the classification and prediction of efficiency scores, without applying any DEA models.Keywords: data envelopment analysis, interval DEA, efficiency classification, efficiency prediction
Procedia PDF Downloads 1645139 Influence of Nanomaterials on the Properties of Shape Memory Polymeric Materials
Authors: Katielly Vianna Polkowski, Rodrigo Denizarte de Oliveira Polkowski, Cristiano Grings Herbert
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The use of nanomaterials in the formulation of polymeric materials modifies their molecular structure, offering an infinite range of possibilities for the development of smart products, being of great importance for science and contemporary industry. Shape memory polymers are generally lightweight, have high shape recovery capabilities, they are easy to process and have properties that can be adapted for a variety of applications. Shape memory materials are active materials that have attracted attention due to their superior damping properties when compared to conventional structural materials. The development of methodologies capable of preparing new materials, which use graphene in their structure, represents technological innovation that transforms low-cost products into advanced materials with high added value. To obtain an improvement in the shape memory effect (SME) of polymeric materials, it is possible to use graphene in its composition containing low concentration by mass of graphene nanoplatelets (GNP), graphene oxide (GO) or other functionalized graphene, via different mixture process. As a result, there was an improvement in the SME, regarding the increase in the values of maximum strain. In addition, the use of graphene contributes to obtaining nanocomposites with superior electrical properties, greater crystallinity, as well as resistance to material degradation. The methodology used in the research is Systematic Review, scientific investigation, gathering relevant studies on influence of nanomaterials on the properties of shape memory polymeric, using the literature database as a source and study methods. In the present study, a systematic reviewwas performed of all papers published from 2014 to 2022 regarding graphene and shape memory polymeric througha search of three databases. This study allows for easy identification of themost relevant fields of study with respect to graphene and shape memory polymeric, as well as the main gaps to beexplored in the literature. The addition of graphene showed improvements in obtaining higher values of maximum deformation of the material, attributed to a possible slip between stacked or agglomerated nanostructures, as well as an increase in stiffness due to the increase in the degree of phase separation that results in a greater amount physical cross-links, referring to the formation of shortrange rigid domains.Keywords: graphene, shape memory, smart materials, polymers, nanomaterials
Procedia PDF Downloads 845138 Effect of Texturised Soy Protein and Yeast on the Instrumental and Sensory Quality of Hybrid Beef Meatballs
Authors: Simona Grasso, Gabrielle Smith, Sophie Bowers, Oluseyi Moses Ajayi, Mark Swainson
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Hybrid meat analogues are meat products whereby a proportion of meat has been partially replaced by more sustainable protein sources. These products could bridge the gap between meat and meat-free products, providing convenience, and allowing consumers to continue using meat products as they conventionally would, while lowering their overall meat intake. The study aimed to investigate the effect of introducing texturized soy protein (TSP) at different levels (15% and 30%) with and without nutritional yeast as flavour enhancer on the sensory and instrumental quality of beef meatballs, compared to a soy and yeast-free control. Proximate analysis, yield, colour, instrumental texture, and sensory quality were investigated. The addition of soy and yeast did not have significant effects on the overall protein content, but the total fat and moisture content went down with increasing soy substitution. Samples with 30% TSP had significantly higher yield than the other recipes. In terms of colour, a* redness values tended to go down and b* yellowness values tended to go up with increasing soy addition. The addition of increasing levels of soy and yeast modified the structure of meatballs resulting in a progressive decrease in hardness and chewiness compared to control. Sixty participants assessed the samples using Check-all-that-apply (CATA) questions and hedonic scales. The texture of all TSP-containing samples received significantly higher acceptability scores than control, while 15% TSP with yeast received significantly higher flavour and overall acceptability scores than control. Control samples were significantly more often associated than the other recipes to the term 'hard' and the least associated to 'soft' and 'crumbly and easy to cut'. All recipes were similarly associated to the terms 'weak meaty', 'strong meaty', 'characteristic' and 'unusual'. Correspondence analysis separated the meatballs in three distinct groups: 1) control; 2) 30%TSP with yeast; and 3) 15%TSP, 15%TSP with yeast and 30%TSP located together on the sensory map, showing similarity. Adding 15-30% TSP with or without yeast inclusion could be beneficial for the development of future meat hybrids with acceptable sensory quality. These results can provide encouragement for the use of the hybrid concept by the meat industry to promote the partial substitution of meat in flexitarians’ diets.Keywords: CATA, hybrid meat products, texturised soy protein, yeast
Procedia PDF Downloads 1655137 Classification of Digital Chest Radiographs Using Image Processing Techniques to Aid in Diagnosis of Pulmonary Tuberculosis
Authors: A. J. S. P. Nileema, S. Kulatunga , S. H. Palihawadana
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Computer aided detection (CAD) system was developed for the diagnosis of pulmonary tuberculosis using digital chest X-rays with MATLAB image processing techniques using a statistical approach. The study comprised of 200 digital chest radiographs collected from the National Hospital for Respiratory Diseases - Welisara, Sri Lanka. Pre-processing was done to remove identification details. Lung fields were segmented and then divided into four quadrants; right upper quadrant, left upper quadrant, right lower quadrant, and left lower quadrant using the image processing techniques in MATLAB. Contrast, correlation, homogeneity, energy, entropy, and maximum probability texture features were extracted using the gray level co-occurrence matrix method. Descriptive statistics and normal distribution analysis were performed using SPSS. Depending on the radiologists’ interpretation, chest radiographs were classified manually into PTB - positive (PTBP) and PTB - negative (PTBN) classes. Features with standard normal distribution were analyzed using an independent sample T-test for PTBP and PTBN chest radiographs. Among the six features tested, contrast, correlation, energy, entropy, and maximum probability features showed a statistically significant difference between the two classes at 95% confidence interval; therefore, could be used in the classification of chest radiograph for PTB diagnosis. With the resulting value ranges of the five texture features with normal distribution, a classification algorithm was then defined to recognize and classify the quadrant images; if the texture feature values of the quadrant image being tested falls within the defined region, it will be identified as a PTBP – abnormal quadrant and will be labeled as ‘Abnormal’ in red color with its border being highlighted in red color whereas if the texture feature values of the quadrant image being tested falls outside of the defined value range, it will be identified as PTBN–normal and labeled as ‘Normal’ in blue color but there will be no changes to the image outline. The developed classification algorithm has shown a high sensitivity of 92% which makes it an efficient CAD system and with a modest specificity of 70%.Keywords: chest radiographs, computer aided detection, image processing, pulmonary tuberculosis
Procedia PDF Downloads 1265136 MAOD Is Estimated by Sum of Contributions
Authors: David W. Hill, Linda W. Glass, Jakob L. Vingren
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Maximal accumulated oxygen deficit (MAOD), the gold standard measure of anaerobic capacity, is the difference between the oxygen cost of exhaustive severe intensity exercise and the accumulated oxygen consumption (O2; mL·kg–1). In theory, MAOD can be estimated as the sum of independent estimates of the phosphocreatine and glycolysis contributions, which we refer to as PCr+glycolysis. Purpose: The purpose was to test the hypothesis that PCr+glycolysis provides a valid measure of anaerobic capacity in cycling and running. Methods: The participants were 27 women (mean ± SD, age 22 ±1 y, height 165 ± 7 cm, weight 63.4 ± 9.7 kg) and 25 men (age 22 ± 1 y, height 179 ± 6 cm, weight 80.8 ± 14.8 kg). They performed two exhaustive cycling and running tests, at speeds and work rates that were tolerable for ~5 min. The rate of oxygen consumption (VO2; mL·kg–1·min–1) was measured in warmups, in the tests, and during 7 min of recovery. Fingerprick blood samples obtained after exercise were analysed to determine peak blood lactate concentration (PeakLac). The VO2 response in exercise was fitted to a model, with a fast ‘primary’ phase followed by a delayed ‘slow’ component, from which was calculated the accumulated O2 and the excess O2 attributable to the slow component. The VO2 response in recovery was fitted to a model with a fast phase and slow component, sharing a common time delay. Oxygen demand (in mL·kg–1·min–1) was determined by extrapolation from steady-state VO2 in warmups; the total oxygen cost (in mL·kg–1) was determined by multiplying this demand by time to exhaustion and adding the excess O2; then, MAOD was calculated as total oxygen cost minus accumulated O2. The phosphocreatine contribution (area under the fast phase of the post-exercise VO2) and the glycolytic contribution (converted from PeakLac) were summed to give PCr+glycolysis. There was not an interaction effect involving sex, so values for anaerobic capacity were examined using a two-way ANOVA, with repeated measures across method (PCr+glycolysis vs MAOD) and mode (cycling vs running). Results: There was a significant effect only for exercise mode. There was no difference between MAOD and PCr+glycolysis: values were 59 ± 6 mL·kg–1 and 61 ± 8 mL·kg–1 in cycling and 78 ± 7 mL·kg–1 and 75 ± 8 mL·kg–1 in running. Discussion: PCr+glycolysis is a valid measure of anaerobic capacity in cycling and running, and it is as valid for women as for men.Keywords: alactic, anaerobic, cycling, ergometer, glycolysis, lactic, lactate, oxygen deficit, phosphocreatine, running, treadmill
Procedia PDF Downloads 1365135 Detecting Tomato Flowers in Greenhouses Using Computer Vision
Authors: Dor Oppenheim, Yael Edan, Guy Shani
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This paper presents an image analysis algorithm to detect and count yellow tomato flowers in a greenhouse with uneven illumination conditions, complex growth conditions and different flower sizes. The algorithm is designed to be employed on a drone that flies in greenhouses to accomplish several tasks such as pollination and yield estimation. Detecting the flowers can provide useful information for the farmer, such as the number of flowers in a row, and the number of flowers that were pollinated since the last visit to the row. The developed algorithm is designed to handle the real world difficulties in a greenhouse which include varying lighting conditions, shadowing, and occlusion, while considering the computational limitations of the simple processor in the drone. The algorithm identifies flowers using an adaptive global threshold, segmentation over the HSV color space, and morphological cues. The adaptive threshold divides the images into darker and lighter images. Then, segmentation on the hue, saturation and volume is performed accordingly, and classification is done according to size and location of the flowers. 1069 images of greenhouse tomato flowers were acquired in a commercial greenhouse in Israel, using two different RGB Cameras – an LG G4 smartphone and a Canon PowerShot A590. The images were acquired from multiple angles and distances and were sampled manually at various periods along the day to obtain varying lighting conditions. Ground truth was created by manually tagging approximately 25,000 individual flowers in the images. Sensitivity analyses on the acquisition angle of the images, periods throughout the day, different cameras and thresholding types were performed. Precision, recall and their derived F1 score were calculated. Results indicate better performance for the view angle facing the flowers than any other angle. Acquiring images in the afternoon resulted with the best precision and recall results. Applying a global adaptive threshold improved the median F1 score by 3%. Results showed no difference between the two cameras used. Using hue values of 0.12-0.18 in the segmentation process provided the best results in precision and recall, and the best F1 score. The precision and recall average for all the images when using these values was 74% and 75% respectively with an F1 score of 0.73. Further analysis showed a 5% increase in precision and recall when analyzing images acquired in the afternoon and from the front viewpoint.Keywords: agricultural engineering, image processing, computer vision, flower detection
Procedia PDF Downloads 3295134 Biomechanical Analysis on Skin and Jejunum of Chemically Prepared Cat Cadavers Used in Surgery Training
Authors: Raphael C. Zero, Thiago A. S. S. Rocha, Marita V. Cardozo, Caio C. C. Santos, Alisson D. S. Fechis, Antonio C. Shimano, FabríCio S. Oliveira
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Biomechanical analysis is an important factor in tissue studies. The objective of this study was to determine the feasibility of a new anatomical technique and quantify the changes in skin and the jejunum resistance of cats’ corpses throughout the process. Eight adult cat cadavers were used. For every kilogram of weight, 120ml of fixative solution (95% 96GL ethyl alcohol and 5% pure glycerin) was applied via the external common carotid artery. Next, the carcasses were placed in a container with 96 GL ethyl alcohol for 60 days. After fixing, all carcasses were preserved in a 30% sodium chloride solution for 60 days. Before fixation, control samples were collected from fresh cadavers and after fixation, three skin and jejunum fragments from each cadaver were tested monthly for strength and displacement until complete rupture in a universal testing machine. All results were analyzed by F-test (P <0.05). In the jejunum, the force required to rupture the fresh samples and the samples fixed in alcohol for 60 days was 31.27±19.14N and 29.25±11.69N, respectively. For the samples preserved in the sodium chloride solution for 30 and 60 days, the strength was 26.17±16.18N and 30.57±13.77N, respectively. In relation to the displacement required for the rupture of the samples, the values of fresh specimens and those fixed in alcohol for 60 days was 2.79±0.73mm and 2.80±1.13mm, respectively. For the samples preserved for 30 and 60 days with sodium chloride solution, the displacement was 2.53±1.03mm and 2.83±1.27mm, respectively. There was no statistical difference between the samples (P=0.68 with respect to strength, and P=0.75 with respect to displacement). In the skin, the force needed to rupture the fresh samples and the samples fixed for 60 days in alcohol was 223.86±131.5N and 211.86±137.53N respectively. For the samples preserved in sodium chloride solution for 30 and 60 days, the force was 227.73±129.06 and 224.78±143.83N, respectively. In relation to the displacement required for the rupture of the samples, the values of fresh specimens and those fixed in alcohol for 60 days were 3.67±1.03mm and 4.11±0.87mm, respectively. For the samples preserved for 30 and 60 days with sodium chloride solution, the displacement was 4.21±0.93mm and 3.93±0.71mm, respectively. There was no statistical difference between the samples (P=0.65 with respect to strength, and P=0.98 with respect to displacement). The resistance of the skin and intestines of the cat carcasses suffered little change when subjected to alcohol fixation and preservation in sodium chloride solution, each for 60 days, which is promising for use in surgery training. All experimental procedures were approved by the Municipal Legal Department (protocol 02.2014.000027-1). The project was funded by FAPESP (protocol 2015-08259-9).Keywords: anatomy, conservation, fixation, small animal
Procedia PDF Downloads 2965133 Nanotechnology for Flame Retardancy of Thermoset Resins
Authors: Ewa Kicko Walczak, Grazyna Rymarz
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In recent years, nanotechnology has been successfully applied for flame retardancy of polymers, in particular for construction materials. The consumption of thermoset resins as a construction polymers materials is approximately over one million tone word wide. Excellent mechanical, relatively high heat and thermal stability of their type of polymers are proven for variety applications, e.g. transportation, electrical, electronic, building part industry. Above applications in addition to the strength and thermal properties also requires -referring to the legal regulation or recommendation - an adequate level of flammability of the materials. This publication present the evaluation was made of effectiveness of flame retardancy of halogen-free hybrid flame retardants(FR) as compounds nitric/phosphorus modifiers that act with nanofillers (nano carbons, organ modified montmorillonite, nano silica, microsphere) in relation to unsaturated polyester/epoxy resins and glass-reinforced on base this resins laminates(GRP) as a final products. The analysis of the fire properties provided proof of effective flame retardancy of the tested composites by defining oxygen indices values (LOI), with the use of thermogravimetric methods (TGA) and combustion head (CH). An analysis of the combustion process with Cone Calorimeter (CC) method included in the first place N/P units and nanofillers with the observed phenomenon of synergic action of compounds. The fine-plates, phase morphology and rheology of composites were assessed by SEM/ TEM analysis. Polymer-matrix glass reinforced laminates with modified resins meet LOI over 30%, reduced in a decrease by 70% HRR (according to CC analysis), positive description of the curves TGA and values CH; no adverse negative impact on mechanical properties. The main objective of our current project is to contribute to the general understanding of the flame retardants mechanism and to investigate the corresponding structure/properties relationships. We confirm that nanotechnology systems are successfully concept for commercialized forms for non-flammable GRP pipe, concrete composites, and flame retardant tunnels constructions.Keywords: fire retardants, FR, halogen-free FR nanofillers, non-flammable pipe/concrete, thermoset resins
Procedia PDF Downloads 2845132 Enhanced Dielectric and Ferroelectric Properties in Holmium Substituted Stoichiometric and Non-Stoichiometric SBT Ferroelectric Ceramics
Authors: Sugandha Gupta, Arun Kumar Jha
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A large number of ferroelectric materials have been intensely investigated for applications in non-volatile ferroelectric random access memories (FeRAMs), piezoelectric transducers, actuators, pyroelectric sensors, high dielectric constant capacitors, etc. Bismuth layered ferroelectric materials such as Strontium Bismuth Tantalate (SBT) has attracted a lot of attention due to low leakage current, high remnant polarization and high fatigue endurance up to 1012 switching cycles. However, pure SBT suffers from various major limitations such as high dielectric loss, low remnant polarization values, high processing temperature, bismuth volatilization, etc. Significant efforts have been made to improve the dielectric and ferroelectric properties of this compound. Firstly, it has been reported that electrical properties vary with the Sr/ Bi content ratio in the SrBi2Ta2O9 compsition i.e. non-stoichiometric compositions with Sr-deficient / Bi excess content have higher remnant polarization values than stoichiometic SBT compositions. With the objective to improve structural, dielectric, ferroelectric and piezoelectric properties of SBT compound, rare earth holmium (Ho3+) was chosen as a donor cation for substitution onto the Bi2O2 layer. Moreover, hardly any report on holmium substitution in stoichiometric SrBi2Ta2O9 and non-stoichiometric Sr0.8Bi2.2Ta2O9 compositions were available in the literature. The holmium substituted SrBi2-xHoxTa2O9 (x= 0.00-2.0) and Sr0.8Bi2.2Ta2O9 (x=0.0 and 0.01) compositions were synthesized by the solid state reaction method. The synthesized specimens were characterized for their structural and electrical properties. X-ray diffractograms reveal single phase layered perovskite structure formation for holmium content in stoichiometric SBT samples up to x ≤ 0.1. The granular morphology of the samples was investigated using scanning electron microscope (Hitachi, S-3700 N). The dielectric measurements were carried out using a precision LCR meter (Agilent 4284A) operating at oscillation amplitude of 1V. The variation of dielectric constant with temperature shows that the Curie temperature (Tc) decreases on increasing the holmium content. The specimen with x=2.0 i.e. the bismuth free specimen, has very low dielectric constant and does not show any appreciable variation with temperature. The dielectric loss reduces significantly with holmium substitution. The polarization–electric field (P–E) hysteresis loops were recorded using a P–E loop tracer based on Sawyer–Tower circuit. It is observed that the ferroelectric property improve with Ho substitution. Holmium substituted specimen exhibits enhanced value of remnant polarization (Pr= 9.22 μC/cm²) as compared to holmium free specimen (Pr= 2.55 μC/cm²). Piezoelectric co-efficient (d33 values) was measured using a piezo meter system (Piezo Test PM300). It is observed that holmium substitution enhances piezoelectric coefficient. Further, the optimized holmium content (x=0.01) in stoichiometric SrBi2-xHoxTa2O9 composition has been substituted in non-stoichiometric Sr0.8Bi2.2Ta2O9 composition to obtain further enhanced structural and electrical characteristics. It is expected that a new class of ferroelectric materials i.e. Rare Earth Layered Structured Ferroelectrics (RLSF) derived from Bismuth Layered Structured Ferroelectrics (BLSF) will generate which can be used to replace static (SRAM) and dynamic (DRAM) random access memories with ferroelectric random access memories (FeRAMS).Keywords: dielectrics, ferroelectrics, piezoelectrics, strontium bismuth tantalate
Procedia PDF Downloads 2095131 A Comparative Study on Vowel Articulation in Malayalam Speaking Children Using Cochlear Implant
Authors: Deepthy Ann Joy, N. Sreedevi
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Hearing impairment (HI) at an early age, identified before the onset of language development can reduce the negative effect on speech and language development of children. Early rehabilitation is very important in the improvement of speech production in children with HI. Other than conventional hearing aids, Cochlear Implants are being used in the rehabilitation of children with HI. However, delay in acquisition of speech and language milestones persist in children with Cochlear Implant (CI). Delay in speech milestones are reflected through speech sound errors. These errors reflect the temporal and spectral characteristics of speech. Hence, acoustical analysis of the speech sounds will provide a better representation of speech production skills in children with CI. The present study aimed at investigating the acoustic characteristics of vowels in Malayalam speaking children with a cochlear implant. The participants of the study consisted of 20 Malayalam speaking children in the age range of four and seven years. The experimental group consisted of 10 children with CI, and the control group consisted of 10 typically developing children. Acoustic analysis was carried out for 5 short (/a/, /i/, /u/, /e/, /o/) and 5 long vowels (/a:/, /i:/, /u:/, /e:/, /o:/) in word-initial position. The responses were recorded and analyzed for acoustic parameters such as Vowel duration, Ratio of the duration of a short and long vowel, Formant frequencies (F₁ and F₂) and Formant Centralization Ratio (FCR) computed using the formula (F₂u+F₂a+F₁i+F₁u)/(F₂i+F₁a). Findings of the present study indicated that the values for vowel duration were higher in experimental group compared to the control group for all the vowels except for /u/. Ratio of duration of short and long vowel was also found to be higher in experimental group compared to control group except for /i/. Further F₁ for all vowels was found to be higher in experimental group with variability noticed in F₂ values. FCR was found be higher in experimental group, indicating vowel centralization. Further, the results of independent t-test revealed no significant difference across the parameters in both the groups. It was found that the spectral and temporal measures in children with CI moved towards normal range. The result emphasizes the significance of early rehabilitation in children with hearing impairment. The role of rehabilitation related aspects are also discussed in detail which can be clinically incorporated for the betterment of speech therapeutic services in children with CI.Keywords: acoustics, cochlear implant, Malayalam, vowels
Procedia PDF Downloads 1445130 The Image as an Initial Element of the Cognitive Understanding of Words
Authors: S. Pesina, T. Solonchak
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An analysis of word semantics focusing on the invariance of advanced imagery in several pressing problems. Interest in the language of imagery is caused by the introduction, in the linguistics sphere, of a new paradigm, the center of which is the personality of the speaker (the subject of the language). Particularly noteworthy is the question of the place of the image when discussing the lexical, phraseological values and the relationship of imagery and metaphors. In part, the formation of a metaphor, as an interaction between two intellective entities, occurs at a cognitive level, and it is the category of the image, having cognitive roots, which aides in the correct interpretation of the results of this process on the lexical-semantic level.Keywords: image, metaphor, concept, creation of a metaphor, cognitive linguistics, erased image, vivid image
Procedia PDF Downloads 3615129 Power Management in Wireless Combustible Gas Sensors
Authors: Denis Spirjakin, Alexander Baranov, Saba Akbari, Natalia Kalenova, Vladimir Sleptsov
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In this paper we propose the approach to power management in wireless combustible gas sensors. This approach makes possible drastically prolong sensor nodes autonomous lifetime. That is necessary to tie battery replacement to every year technical service procedures which are claimed by safety standards. Using this approach the current consumption of the wireless combustible gas sensor node was decreased from 80 mA to less than 2 mA and the power consumption from more than 220 mW to 4.6 mW. These values provide autonomous lifetime of the node more than one year.Keywords: Gas sensors, power management, wireless sensor network
Procedia PDF Downloads 7245128 Low Plastic Deformation Energy to Induce High Superficial Strain on AZ31 Magnesium Alloy Sheet
Authors: Emigdio Mendoza, Patricia Fernandez, Cristian Gomez
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Magnesium alloys have generated great interest for several industrial applications because their high specific strength and low density make them a very attractive alternative for the manufacture of various components; however, these alloys present a limitation with their hexagonal crystal structure that limits the deformation mechanisms at room temperature likewise the molding components alternatives, it is for this reason that severe plastic deformation processes have taken a huge relevance recently because these, allow high deformation rates to be applied that induce microstructural changes where the deficiency in the sliding systems is compensated with crystallographic grains reorientations or crystal twinning. The present study reports a statistical analysis of process temperature, number of passes and shear angle with respect to the shear stress in severe plastic deformation process denominated 'Equal Channel Angular Sheet Drawing (ECASD)' applied to the magnesium alloy AZ31B through Python Statsmodels libraries, additionally a Post-Hoc range test is performed using the Tukey statistical test. Statistical results show that each variable has a p-value lower than 0.05, which allows comparing the average values of shear stresses obtained, which are in the range of 7.37 MPa to 12.23 MPa, lower values in comparison to others severe plastic deformation processes reported in the literature, considering a value of 157.53 MPa as the average creep stress for AZ31B alloy. However, a higher stress level is required when the sheets are processed using a shear angle of 150°, due to a higher level of adjustment applied for the shear die of 150°. Temperature and shear passes are important variables as well, but there is no significant impact on the level of stress applied during the ECASD process. In the processing of AZ31B magnesium alloy sheets, ECASD technique is evidenced as a viable alternative in the modification of the elasto-plastic properties of this alloy, promoting the weakening of the basal texture, which means, a better response to deformation, whereby, during the manufacture of parts by drawing or stamping processes the formation of cracks on the surface can be reduced, presenting an adequate mechanical performance.Keywords: plastic deformation, strain, sheet drawing, magnesium
Procedia PDF Downloads 1095127 Becoming a Good-Enough White Therapist: Experiences of International Students in Psychology Doctoral Programs
Authors: Mary T. McKinley
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As socio-economic globalization impacts education and turns knowledge into a commodity, institutions of higher education are becoming more intentional about infusing a global and intercultural perspective into education via the recruitment of international students. Coming from dissimilar cultures, many of these students are evaluated and held accountable to Euro-American values of independence, self-reliance, and autonomy. Not surprisingly, these students often experience culture shock with deleterious effects on their mental health and academic functioning. Thus, it is critical to understand the experiences of international students with the hope that such knowledge will keep the field of psychology from promulgating Eurocentric ideals and values and prevent the training of these students as good-enough White therapists. Using a critical narrative inquiry framework, this study elicits stories about the challenges encountered by international students as they navigate their clinical training in the presence of acculturative stress and potentially different worldviews. With its emphasis on story-telling as meaning making, narrative research design is hinged on the assumption that people are interpretive beings who make meaning of themselves and their world through the language of stories. Also, dominant socially-constructed narratives play a central role in creating and maintaining hegemonic structures that privilege certain individuals and ideologies at the expense of others. On this premise, narrative inquiry begins with an exploration of the experiences of participants in their lived stories. Bounded narrative segments were read, interpreted, and analyzed using a critical events approach. Throughout the process, issues of reliability and researcher bias were addressed by keeping a reflective analytic memo, as well as triangulating the data using peer-reviewers and check-ins with participants. The findings situate culture at the epicenter of international students’ acculturation challenges as well as their resiliency in psychology doctoral programs. It was not uncommon for these international students to experience ethical dilemmas inherent in learning content that conflicted with their cultural beliefs and values. Issues of cultural incongruence appear to be further exacerbated by visible markers for differences like speech accent and clothing attire. These stories also link the acculturative stress reported by international students to the experiences of perceived racial discrimination and lack of support from the faculty, administration, peers, and the society at large. Beyond the impact on the international students themselves, there are implications for internationalization in psychology with the goal of equipping doctoral programs to be better prepared to meet the needs of their international students. More than ever before, programs need to liaise with international students’ services and work in tandem to meet the unique needs of this population of students. Also, there exists a need for multiculturally competent supervisors working with international students with varying degrees of acculturation. In addition to making social justice and advocacy salient in students’ multicultural training, it may be helpful for psychology doctoral programs to be more intentional about infusing cross-cultural theories, indigenous psychotherapies, and/or when practical, the possibility for geographically cross-cultural practicum experiences in the home countries of international students while taking into consideration the ethical issues for virtual supervision.Keywords: decolonizing pedagogies, international students, multiculturalism, psychology doctoral programs
Procedia PDF Downloads 1195126 The Vanishing Treasure: An Anthropological Study on Changing Social Relationships, Values, Belief System and Language Pattern of the Limbus in Kalimpong Sub-Division of the Darjeeling District in West Bengal, India
Authors: Biva Samadder, Samita Manna
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India is a melting pot of races, tribes, castes and communities. The population of India can be roughly branched into the huge majority of “Civilized” Indians of the Plains and the minority of Tribal population of the hill area and the forest who constituting almost 16 percent of total population of India. The Kirat community composed of four ethnic tribes: Limbu, Lepcha, Dhimal, and Rai. These Kirat people were found to be rich in indigenous knowledge, skill and practices especially for the use on medicinal plants and livelihood purposes. The “Mundhum" is the oral scripture or the “Bible of the Limbus” which serves as the canon of the codes of the Limbu socialization, their moral values and the very orientation of their lifestyle. From birth till death the Limbus are disciplined in the life with full of religious rituals, traditions and culture governed by community norms with a rich legacy of indigenous knowledge and traditional practices. The present study has been conducted using both secondary as well as primary data by applying social methodology consisting of the social survey, questionnaire, interviews and observations in the Kalimpong Block-I of Darjeeling District of west Bengal of India, which is a heterogeneous zone in terms of its ethnic composition and where the Limbus are pre-dominantly concentrated. Due to their close contact with other caste and communities Limbus are now adjusted with the changing situation by borrowing some cultural traits from the other communities and changes that have taken place in their cultural practices, religious beliefs, economic aspects, languages and in social roles and relationships which is bringing the change in their material culture. Limbu language is placed in the Tibeto- Burman Language category. But due to the political and cultural domination of educationally sound and numerically dominant Bengali race, the different communities in this area forced to come under the one umbrella of the Nepali or Gorkhali nation (nation-people). Their respective identities had to be submerged in order to constitute as a strong force to resist Nepali domination and ensure their common survival. As Nepali is a lingua-franca of the area knowing and speaking Nepali language helps them in procuring economic and occupational facilities. Ironically, present day younger generation does not feel comfortable speaking in their own Limbu tongue. The traditional knowledge about medicinal plants, healing, and health culture is found to be wear away due to the lack of interest of young generation. Not only poverty, along with exclusion due to policies they are in the phase of extinction, but their capabilities are ignored and not documented and preserved especially in the case of Limbus who having a great cultural heritage of an oral tradition. Attempts have been made to discuss the persistence and changes in socioeconomic pattern of life in relation to the social structure, material culture, cultural practices, social relationships, indigenous technology, ethos and their values and belief system.Keywords: changing social relationship, cultural transition, identity, indigenous knowledge, language
Procedia PDF Downloads 1725125 Study of Pulmonary Function Test of over the 40 Years Adults in Ulaanbaatar
Authors: D. Densenbal, Ts. Naidansuren, M. Oyunchimeg, Ts. Manaljav, D. Udval, L. Khosbayar, Kh. Solongo, D. Ichinnorov, B. Solongo
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Background: The rapid economic growth and to the common use of smoky fuel such as coal in the small traditional houses (Ger) in Mongolia is worsening its air pollution problem. In addition, the smoking rate is considered to be high. Despite these conditions, few prevalence studies of COPD epidemiology and diagnose have been performed in Mongolia. The spirometric test is a widely used diagnose for COPD. Aims: Healthy and over the 40 aged adults were evaluated of Pulmonary function test in Ulaanbaatar. Methods: Healthy, over the 40 aged residences were admitted for this study from II sub-district, in Khan-Uul district of Ulaanbaatar city. In this cross-sectional study. Health information was collected 184 subjects between 01-03 July in 2013; spirometry device was named Hichest–105 Japan that was employed for this study. Studies were using the acceptability standards outlined, and data were compared with personal reference data generated on Asian subjects which were performed abnormally to evaluated by global initiative obstructive lung decreases (GOLD). Data were analyzed using SPSS 20 software. Results: A total of 134 subjects (age 52.9±9.8, man 32.8%) were performed PFT which were interpreted normal 73.9% (sum of man 65.0% and woman 79.4% ), abnormal 26.1% which were typed obstruction 17.2% (23), restriction 6% (8), mixed 3% (4). Airflow obstruction were determined in all man 25% (11), woman 13.3% (12) which were classified mild 43.4% (man 54.5%, woman 33.3%), moderate 52.2% (36.3% vs. 66.7%) and severe 4.3% man 1 GOLD degree. Undetermined a very severe obstruction. Normal PFT subjects were compared a group of gender and age group which man was significantly higher than the women (p<0.05). Age group of PFT decrease was no difference in gender (p>0.05) also no difference in BMI (p>0.05). Normal PFT subjects were compared with predicted values were used to Asian population which was significantly lower than FEV1 (0.15±0.36 l), PEF (1.92±1.31 l) and same deference occurred man (FEV1 0.19±0.42 l, PEF 2.04±1.64), women (0.14±0.33 l vs. 1.86±1.15 l). The decrease of FEV1 was defined in over the 60 age group higher than other age groups. Conclusion: Not only observed an air flow limitation prevalence dominance in all case but also COPD prevalence diagnosed man were higher than women. Normal PFT subjects were compared with predicted values were used to Asian population which was significant air flow limitation started early.Keywords: PFT, obstruction, FEV1, COPD
Procedia PDF Downloads 2185124 The Impact of Total Dust (LGS) and Mineral Dust (PM 10) in Cardio Vascular and Respiratory System, in Albania: A Longitudinal Study
Authors: Canga Mimoza, Irene Malagnino, Giulia Malagnino, Vito Malagnino
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Aim: This study aims at evaluating the impact of total dust (LGS) and mineral dust (PM10), in the cardio vascular and respiratory systems. Also proving that these air polluters are the cause of several diseases, such as bronchopneumonia, pneumonia, bronchitis, angina pectoris and cardiac insufficiency. Material and Method: The study is concentrated in the cities of Fier and Vlora. This is a clinic-epidemiological study conducted during the time period 2014-2019. Some of the data of LGS and PM10 were obtained from the database of the Institute of Public Health. The formula to measure the mean value of LGS and PM10 is ∆X=X (mean)-Xᵢ. Results: Based on the calculations made, we noticed that: The mean value of LGS in the city of Fieri was 227,33, while the mean value of LGS in the city of Vlora was 177,4. Whereas, the mean value of PM10 in the city of Fieri was 105.5 and the mean value of PM10 in the city of Vlore was 77.5. According to, our statistics the values of LGS were 1.2 times higher in Fier than in Vlora and the PM10 values were 1.36 times higher in Fier than in Vlora. Based on the data, in the city of Fier, the incidence of the bronchopneumonia was 56.53 sick patients/1000 inhabitants, but in Vlora, it was 22 sick patients/1000 inhabitants, so the number of the sick patients was 2.5 times higher in the city of Fieri compared with Vlora city, (P=0.001). The number of the patients with bronchitis, in the city of Fier, was 18 patients/1000 inhabitants, whereas, in Vlora, it was 9 patients/1000 inhabitants, (P=0.005). Based on the data, 8 patients/1000 inhabitants in the city of Fier, suffered from the pneumonia disease, while in Vlora city, were 4 patients/1000 inhabitants, (P=0.005). Another disease taken in consideration was angina pectoris. This study can claim that in the city of Fier, 9.5 patients/1000 inhabitants suffered from this disease, while in Vlora city, were only 4 patients /1000 inhabitants, (P=0.001). Findings of the present study proved that 3.7 patients/1000 inhabitants in the city of Fieri, had cardiac insufficiency, whereas in the city of Vlora, were 1.8 patients/1000 inhabitants, (P=0.05). Conclusions: LGS and PM10 have an influential impact on the cardio vascular and respiratory system; that’s why their levels should be kept under control. The pollution levels are 1.2 and 1.4 times higher in Fier than in Vlora; also the incidences of the diseases are 2 times higher in Fier than in Vlora. Recommendations: In order to prevent the cardio vascular and respiratory diseases, we should avoid places where pollution is higher than the norm. This can be achieved by frequenting places where the air pollution is lower, such as parks, gardens, top floors, etc.Keywords: impact of total dust, LGS, mineral dust, PM 10, cardio vascular pathologies, respiratory disease
Procedia PDF Downloads 1285123 Skin-Dose Mapping for Patients Undergoing Interventional Radiology Procedures: Clinical Experimentations versus a Mathematical Model
Authors: Aya Al Masri, Stefaan Carpentier, Fabrice Leroy, Thibault Julien, Safoin Aktaou, Malorie Martin, Fouad Maaloul
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Introduction: During an 'Interventional Radiology (IR)' procedure, the patient's skin-dose may become very high for a burn, necrosis and ulceration to appear. In order to prevent these deterministic effects, an accurate calculation of the patient skin-dose mapping is essential. For most machines, the 'Dose Area Product (DAP)' and fluoroscopy time are the only information available for the operator. These two parameters are a very poor indicator of the peak skin dose. We developed a mathematical model that reconstructs the magnitude (delivered dose), shape, and localization of each irradiation field on the patient skin. In case of critical dose exceeding, the system generates warning alerts. We present the results of its comparison with clinical studies. Materials and methods: Two series of comparison of the skin-dose mapping of our mathematical model with clinical studies were performed: 1. At a first time, clinical tests were performed on patient phantoms. Gafchromic films were placed on the table of the IR machine under of PMMA plates (thickness = 20 cm) that simulate the patient. After irradiation, the film darkening is proportional to the radiation dose received by the patient's back and reflects the shape of the X-ray field. After film scanning and analysis, the exact dose value can be obtained at each point of the mapping. Four experimentation were performed, constituting a total of 34 acquisition incidences including all possible exposure configurations. 2. At a second time, clinical trials were launched on real patients during real 'Chronic Total Occlusion (CTO)' procedures for a total of 80 cases. Gafchromic films were placed at the back of patients. We performed comparisons on the dose values, as well as the distribution, and the shape of irradiation fields between the skin dose mapping of our mathematical model and Gafchromic films. Results: The comparison between the dose values shows a difference less than 15%. Moreover, our model shows a very good geometric accuracy: all fields have the same shape, size and location (uncertainty < 5%). Conclusion: This study shows that our model is a reliable tool to warn physicians when a high radiation dose is reached. Thus, deterministic effects can be avoided.Keywords: clinical experimentation, interventional radiology, mathematical model, patient's skin-dose mapping.
Procedia PDF Downloads 1405122 Histopathological Characterization of Prostate Cancer in Saudi Patients
Authors: Nadeem A. Kizilbash
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The study aimed to compare the histopathological characterization of prostate cancer using the conventional and 2005 ISUP modified Gleason system. It employed samples from 40 prostate cancer patients employing resection, biopsies and RP. The majority of cases (95%) comprised adenocarcinoma of the prostate. The results showed that there is migration or upgrading of scores to higher values on using the 2005 ISUP modified Gleason system and an increase in a score of 7 in more than 45% of the cases.Keywords: prostate cancer, conventional gleason grading, 2005 ISUP modified gleason system, histopathology
Procedia PDF Downloads 4275121 A Nanoindentation Study of Thin Film Prepared by Physical Vapor Deposition
Authors: Dhiflaoui Hafedh, Khlifi Kaouther, Ben Cheikh Larbi Ahmed
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Monolayer and multilayer coatings of CrN and AlCrN deposited on 100Cr6 (AISI 52100) substrate by PVD magnetron sputtering system. The micro structures of the coatings were characterized using atomic force microscopy (AFM). The AFM analysis revealed the presence of domes and craters which are uniformly distributed over all surfaces of the various layers. Nano indentation measurement of CrN coating showed maximum hardness (H) and modulus (E) of 14 GPa and 240 GPa, respectively. The measured H and E values of AlCrN coatings were found to be 30 GPa and 382 GPa, respectively. The improved hardness in both the coatings was attributed mainly to a reduction in crystallite size and decrease in surface roughness. The incorporation of Al into the CrN coatings has improved both hardness and Young’s modulus.Keywords: CrN, AlCrN coatings, hardness, nanoindentation
Procedia PDF Downloads 5585120 Investigating the Effects of Data Transformations on a Bi-Dimensional Chi-Square Test
Authors: Alexandru George Vaduva, Adriana Vlad, Bogdan Badea
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In this research, we conduct a Monte Carlo analysis on a two-dimensional χ2 test, which is used to determine the minimum distance required for independent sampling in the context of chaotic signals. We investigate the impact of transforming initial data sets from any probability distribution to new signals with a uniform distribution using the Spearman rank correlation on the χ2 test. This transformation removes the randomness of the data pairs, and as a result, the observed distribution of χ2 test values differs from the expected distribution. We propose a solution to this problem and evaluate it using another chaotic signal.Keywords: chaotic signals, logistic map, Pearson’s test, Chi Square test, bivariate distribution, statistical independence
Procedia PDF Downloads 975119 Hounsfield-Based Automatic Evaluation of Volumetric Breast Density on Radiotherapy CT-Scans
Authors: E. M. D. Akuoko, Eliana Vasquez Osorio, Marcel Van Herk, Marianne Aznar
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Radiotherapy is an integral part of treatment for many patients with breast cancer. However, side effects can occur, e.g., fibrosis or erythema. If patients at higher risks of radiation-induced side effects could be identified before treatment, they could be given more individual information about the risks and benefits of radiotherapy. We hypothesize that breast density is correlated with the risk of side effects and present a novel method for automatic evaluation based on radiotherapy planning CT scans. Methods: 799 supine CT scans of breast radiotherapy patients were available from the REQUITE dataset. The methodology was first established in a subset of 114 patients (cohort 1) before being applied to the whole dataset (cohort 2). All patients were scanned in the supine position, with arms up, and the treated breast (ipsilateral) was identified. Manual experts contour available in 96 patients for both the ipsilateral and contralateral breast in cohort 1. Breast tissue was segmented using atlas-based automatic contouring software, ADMIRE® v3.4 (Elekta AB, Sweden). Once validated, the automatic segmentation method was applied to cohort 2. Breast density was then investigated by thresholding voxels within the contours, using Otsu threshold and pixel intensity ranges based on Hounsfield units (-200 to -100 for fatty tissue, and -99 to +100 for fibro-glandular tissue). Volumetric breast density (VBD) was defined as the volume of fibro-glandular tissue / (volume of fibro-glandular tissue + volume of fatty tissue). A sensitivity analysis was performed to verify whether calculated VBD was affected by the choice of breast contour. In addition, we investigated the correlation between volumetric breast density (VBD) and patient age and breast size. VBD values were compared between ipsilateral and contralateral breast contours. Results: Estimated VBD values were 0.40 (range 0.17-0.91) in cohort 1, and 0.43 (0.096-0.99) in cohort 2. We observed ipsilateral breasts to be denser than contralateral breasts. Breast density was negatively associated with breast volume (Spearman: R=-0.5, p-value < 2.2e-16) and age (Spearman: R=-0.24, p-value = 4.6e-10). Conclusion: VBD estimates could be obtained automatically on a large CT dataset. Patients’ age or breast volume may not be the only variables that explain breast density. Future work will focus on assessing the usefulness of VBD as a predictive variable for radiation-induced side effects.Keywords: breast cancer, automatic image segmentation, radiotherapy, big data, breast density, medical imaging
Procedia PDF Downloads 1325118 FEM Analysis of an Occluded Ear Simulator with Narrow Slit Pathway
Authors: Manabu Sasajima, Takao Yamaguchi, Yoshio Koike, Mitsuharu Watanabe
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This paper discusses the propagation of sound waves in air, specifically in narrow rectangular pathways of an occluded-ear simulator for acoustic measurements. In narrow pathways, both the speed of sound and the phase of the sound waves are affected by the damping of the air viscosity. Herein, we propose a new finite-element method (FEM) that considers the effects of the air viscosity. The method was developed as an extension of existing FEMs for porous, sound-absorbing materials. The results of a numerical calculation for a three-dimensional ear-simulator model using the proposed FEM were validated by comparing with theoretical lumped-parameter modeling analysis and standard values.Keywords: ear simulator, FEM, simulation, viscosity
Procedia PDF Downloads 4435117 Transformation of Bangladesh Society: The Role of Religion
Authors: Abdul Wohab
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Context: The role of religion in the transformation of Bangladesh society has been significant since 1975. There has been a rise in religious presence, particularly Islam, in both private and public spheres supported by the state apparatuses. In 2009, a 'secular' political party came into power for the second time since independence and initiated the modernization of religious education systems. This research focuses on the transformation observed among the educated middle class who now prefer their children to attend modern, English medium madrasas that offer both religion-based and secular education. Research Aim: This research aims to investigate two main questions: a) what motivates the educated middle class to send their children to madrasa education? b) To what extent can it be argued that Bangladeshi society is transforming from its secular nature to being more religious?Methodology: The research applies a combination of primary and secondary methods. Case studies serve as the primary method, allowing for an in-depth exploration of the motivations of the educated middle class. The secondary method involves analyzing published news articles, op-eds, and websites related to madrasa education, as well as studying the reading syllabus of Aliya and Qwami madrasas in Bangladesh. Findings: Preliminary findings indicate that the educated middle class chooses madrasa education for reasons such as remembering and praying for their departed relatives, keeping their children away from substance abuse, fostering moral and ethical values, and instilling respect for seniors and relatives. The research also reveals that religious education is believed to help children remain morally correct according to the Quran and Hadith. Additionally, the establishment of madrasas in Bangladesh is attributed to economic factors, with demand and supply mechanisms playing a significant role. Furthermore, the findings suggest that government-run primary education institutions in rural areas face more challenges in enrollment compared to religious educational institutions like madrasas. Theoretical Importance: This research contributes to the understanding of societal transformation and the role of religion in this process. By examining the case of Bangladesh, it provides insights into how religion influences education choices and societal values. Data Collection and Analysis Procedures: Data for this research is collected through case studies, including interviews and observations of educated middle-class families who send their children to madrasas. In addition, analysis is conducted on relevant published materials such as news articles, op-eds, and websites. The reading syllabus of Aliya and Qwami madrasas is also analyzed to gain a comprehensive understanding of the education system. Questions Addressed: The research addresses two questions: a) what motivates the educated middle class to choose madrasa education for their children? b) To what extent can it be argued that Bangladeshi society is transforming from its secular nature to being more religious?Conclusion: The preliminary findings of this research highlight the motivations of the educated middle class in opting for madrasa education, including the desire to maintain religious traditions, promote moral values, and provide a strong foundation for their children. It also suggests that Bangladeshi society is experiencing a transformation towards a more religious orientation. This research contributes to the understanding of societal changes and the role of religion within Bangladesh, shedding light on the complex dynamics between religion and education.Keywords: madrasa education, transformation, Bangladesh, religion and society, education
Procedia PDF Downloads 645116 Direct Torque Control of Induction Motor Employing Differential Evolution Algorithm
Authors: T. Vamsee Kiran, A. Gopi
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The undesired torque and flux ripple may occur in conventional direct torque control (DTC) induction motor drive. DTC can improve the system performance at low speeds by continuously tuning the regulator by adjusting the Kp, Ki values. In this differential evolution (DE) is proposed to adjust the parameters (Kp, Ki) of the speed controller in order to minimize torque ripple, flux ripple, and stator current distortion.The DE based PI controller has resulted is maintaining a constant speed of the motor irrespective of the load torque fluctuations.Keywords: differential evolution, direct torque control, PI controller
Procedia PDF Downloads 432