Search results for: magnetic field configuration
6830 Evaluating the Validity of CFD Model of Dispersion in a Complex Urban Geometry Using Two Sets of Experimental Measurements
Authors: Mohammad R. Kavian Nezhad, Carlos F. Lange, Brian A. Fleck
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This research presents the validation study of a computational fluid dynamics (CFD) model developed to simulate the scalar dispersion emitted from rooftop sources around the buildings at the University of Alberta North Campus. The ANSYS CFX code was used to perform the numerical simulation of the wind regime and pollutant dispersion by solving the 3D steady Reynolds-averaged Navier-Stokes (RANS) equations on a building-scale high-resolution grid. The validation study was performed in two steps. First, the CFD model performance in 24 cases (eight wind directions and three wind speeds) was evaluated by comparing the predicted flow fields with the available data from the previous measurement campaign designed at the North Campus, using the standard deviation method (SDM), while the estimated results of the numerical model showed maximum average percent errors of approximately 53% and 37% for wind incidents from the North and Northwest, respectively. Good agreement with the measurements was observed for the other six directions, with an average error of less than 30%. In the second step, the reliability of the implemented turbulence model, numerical algorithm, modeling techniques, and the grid generation scheme was further evaluated using the Mock Urban Setting Test (MUST) dispersion dataset. Different statistical measures, including the fractional bias (FB), the geometric mean bias (MG), and the normalized mean square error (NMSE), were used to assess the accuracy of the predicted dispersion field. Our CFD results are in very good agreement with the field measurements.Keywords: CFD, plume dispersion, complex urban geometry, validation study, wind flow
Procedia PDF Downloads 1366829 Theoretical Analysis and Design Consideration of Screened Heat Pipes for Low-Medium Concentration Solar Receivers
Authors: Davoud Jafari, Paolo Di Marco, Alessandro Franco, Sauro Filippeschi
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This paper summarizes the results of an investigation into the heat pipe heat transfer for solar collector applications. The study aims to show the feasibility of a concentrating solar collector, which is coupled with a heat pipe. Particular emphasis is placed on the capillary and boiling limits in capillary porous structures, with different mesh numbers and wick thicknesses. A mathematical model of a cylindrical heat pipe is applied to study its behaviour when it is exposed to higher heat input at the evaporator. The steady state analytical model includes two-dimensional heat conduction in the HP’s wall, the liquid flow in the wick and vapor hydrodynamics. A sensitivity analysis was conducted by considering different design criteria and working conditions. Different wicks (mesh 50, 100, 150, 200, 250, and, 300), different porosities (0.5, 0.6, 0.7, 0.8, and 0.9) with different wick thicknesses (0.25, 0.5, 1, 1.5, and 2 mm) are analyzed with water as a working fluid. Results show that it is possible to improve heat transfer capability (HTC) of a HP by selecting the appropriate wick thickness, the effective pore radius, and lengths for a given HP configuration, and there exist optimal design criteria (optimal thick, evaporator adiabatic and condenser sections). It is shown that the boiling and wicking limits are connected and occurs in dependence on each other. As different parts of the HP external surface collect different fractions of the total incoming insolation, the analysis of non-uniform heat flux distribution indicates that peak heat flux is not affecting parameter. The parametric investigations are aimed to determine working limits and thermal performance of HP for medium temperature SC application.Keywords: screened heat pipes, analytical model, boiling and capillary limits, concentrating collector
Procedia PDF Downloads 5606828 Waste-Based Surface Modification to Enhance Corrosion Resistance of Aluminium Bronze Alloy
Authors: Wilson Handoko, Farshid Pahlevani, Isha Singla, Himanish Kumar, Veena Sahajwalla
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Aluminium bronze alloys are well known for their superior abrasion, tensile strength and non-magnetic properties, due to the co-presence of iron (Fe) and aluminium (Al) as alloying elements and have been commonly used in many industrial applications. However, continuous exposure to the marine environment will accelerate the risk of a tendency to Al bronze alloys parts failures. Although a higher level of corrosion resistance properties can be achieved by modifying its elemental composition, it will come at a price through the complex manufacturing process and increases the risk of reducing the ductility of Al bronze alloy. In this research, the use of ironmaking slag and waste plastic as the input source for surface modification of Al bronze alloy was implemented. Microstructural analysis conducted using polarised light microscopy and scanning electron microscopy (SEM) that is equipped with energy dispersive spectroscopy (EDS). An electrochemical corrosion test was carried out through Tafel polarisation method and calculation of protection efficiency against the base-material was determined. Results have indicated that uniform modified surface which is as the result of selective diffusion process, has enhanced corrosion resistance properties up to 12.67%. This approach has opened a new opportunity to access various industrial utilisations in commercial scale through minimising the dependency on natural resources by transforming waste sources into the protective coating in environmentally friendly and cost-effective ways.Keywords: aluminium bronze, waste-based surface modification, tafel polarisation, corrosion resistance
Procedia PDF Downloads 2366827 Extreme Value Theory Applied in Reliability Analysis: Case Study of Diesel Generator Fans
Authors: Jelena Vucicevic
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Reliability analysis represents a very important task in different areas of work. In any industry, this is crucial for maintenance, efficiency, safety and monetary costs. There are ways to calculate reliability, unreliability, failure density and failure rate. In this paper, the results for the reliability of diesel generator fans were calculated through Extreme Value Theory. The Extreme Value Theory is not widely used in the engineering field. Its usage is well known in other areas such as hydrology, meteorology, finance. The significance of this theory is in the fact that unlike the other statistical methods it is focused on rare and extreme values, and not on average. It should be noted that this theory is not designed exclusively for extreme events, but for extreme values in any event. Therefore, this is a great opportunity to apply the theory and test if it could be applied in this situation. The significance of the work is the calculation of time to failure or reliability in a new way, using statistic. Another advantage of this calculation is that there is no need for technical details and it can be implemented in any part for which we need to know the time to fail in order to have appropriate maintenance, but also to maximize usage and minimize costs. In this case, calculations have been made on diesel generator fans but the same principle can be applied to any other part. The data for this paper came from a field engineering study of the time to failure of diesel generator fans. The ultimate goal was to decide whether or not to replace the working fans with a higher quality fan to prevent future failures. The results achieved in this method will show the approximation of time for which the fans will work as they should, and the percentage of probability of fans working more than certain estimated time. Extreme Value Theory can be applied not only for rare and extreme events, but for any event that has values which we can consider as extreme.Keywords: extreme value theory, lifetime, reliability analysis, statistic, time to failure
Procedia PDF Downloads 3286826 Growth of Metal Oxide (Tio2/Ag) Thin Films Sputtered by Hipims Effective in Bacterial Inactivation: Plasma Chemistry and Energetic
Authors: O. Baghriche, A. Zertal, C. Pulgarin, J. Kiwi, R. Sanjines
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High-Power Impulse Magnetron Sputtering (HIPIMS) is a technology that belongs to the field of Ionized PVD of thin films. This study shows the first complete report on ultrathin TiO2/Ag nano-particulate films sputtered by highly ionized pulsed plasma magnetron sputtering (HIPIMS) leading to fast bacterial loss of viability. The Ag and the TiO2/Ag sputtered films induced complete Escherichia coli inactivation in the dark, which was not observed in the case of TiO2. When Ag was present, the bacterial inactivation was accelerated under low intensity solar simulated light and this has implications for a potential for a practical technology. The design, preparation, testing and surface characterization of these innovative films are described in this study. The HIPIMS sputtered composite films present an appreciable savings in metals compared to films obtained by conventional sputtering methods. HIPIMS sputtering induces a strong interaction with the rugous polyester 3-D structure due to the higher fraction of the Ag-ions (M+) attained in the magnetron chamber. The immiscibility of Ag and TiO2 in the TiO2/Ag films is shown by High Angular Dark Field (HAADF) microscopy. The ionization degree of the film forming species is significantly increased and film growth is assisted by an intense ion flux. Reports have revealed the significant enhancement of the film properties as the HIPIMS technology is used. However, a decrease of the deposition rate, as compared to the conventional DC magnetron sputtering Pulsed (DCMSP) process is commonly observed during HIPIMS.Keywords: E. coli, HIPIMS, inactivation bacterial, sputtering
Procedia PDF Downloads 3006825 Effects of Duct Geometry, Thickness and Types of Liners on Transmission Loss for Absorptive Silencers
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Sound attenuation in absorptive silencers has been analyzed in this paper. The structure of such devices is as follows. When the rigid duct of an expansion chamber has been lined by a packed absorptive material under a perforated membrane, incident sound waves will be dissipated by the absorptive liners. This kind of silencer, usually are applicable for medium to high frequency ranges. Several conditions for different absorptive materials, variety in their thicknesses, and different shapes of the expansion chambers have been studied in this paper. Also, graphs of sound attenuation have been compared between empty expansion chamber and duct of silencer with applying liner. Plane waves have been assumed in inlet and outlet regions of the silencer. Presented results that have been achieved by applying finite element method (FEM), have shown the dependence of the sound attenuation spectrum to flow resistivity and the thicknesses of the absorptive materials, and geometries of the cross section (configuration of the silencer). As flow resistivity and thickness of absorptive materials increase, sound attenuation improves. In this paper, diagrams of the transmission loss (TL) for absorptive silencers in five different cross sections (rectangle, circle, ellipse, square, and rounded rectangle as the main geometry) have been presented. Also, TL graphs for silencers using different absorptive material (glass wool, wood fiber, and kind of spongy materials) as liner with three different thicknesses of 5 mm, 15 mm, and 30 mm for glass wool liner have been exhibited. At first, the effect of substances of the absorptive materials with the specific flow resistivity and densities on the TL spectrum, then the effect of the thicknesses of the glass wool, and at last the efficacy of the shape of the cross section of the silencer have been investigated.Keywords: transmission loss, absorptive material, flow resistivity, thickness, frequency
Procedia PDF Downloads 2506824 The Role of 'Hindu Tantrism' in Conceptualization of the Divine Manifestations in Vajrayana Tradition of Tibetan Buddhism
Authors: Mohammed T. Shabeer
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Hoary moorlands of Tibet bear bundle of religious traditions. Vajrayana tradition of Tibetan Buddhism is one of the deep rooted religious orders of the area. It demands the homage to a variety of gods and diverse worships, especially to manifestations like the Dalai Lamas. This divine diversity has been conceptualized by remoteness of the area and transcontinental intrusion of Asiatic philosophies like Indian Buddhism, Mongolian Shamanism and Hindu Tantrism. This study reveals the role of Hindu Tantrism in conceptualizing the manifestations in Vajrayana Tradition of Tibetan Buddhism in a comparative way. Nowadays, the academic explorations and researches in the field of ‘Tibetology’ are widely tolerable in east and west alike. International community concerns such studies supportive of the restless campaigns for ‘free Tibet’. Moreover, the scientific sources on the topic are rarest and precious in the field of comparative religion. This study reveals a clear account of god concept of Vajrayana tradition and insists that the god concept of the tradition is conceptualized from the amalgamation of Indian Hindu Tantrism, Mongolian Shamanism, and Indian Buddhism. Primly, it sheds the light upon the mysterious similarities between Indian and Tibetan concepts of manifestation of gods. The scientific examination of this problem lasts in the conclusion that the transcontinental transmission of Hindu Tantrism in the special occasion of Buddhist Diaspora of 12th century in consequence of the invasion of Muslim Ghorid Sultanate had paved a vital role in shaping the Vajrayana tradition especially conceptualizing the manifestation of Tibetan gods.Keywords: Buddhist diaspora, Hindu tantrism, manifestation of god, Vajrayana tradition of Tibetan Buddhism
Procedia PDF Downloads 2086823 Can the Intervention of SCAMPER Bring about Changes of Neural Activation While Taking Creativity Tasks?
Authors: Yu-Chu Yeh, WeiChin Hsu, Chih-Yen Chang
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Substitution, combination, modification, putting to other uses, elimination, and rearrangement (SCAMPER) has been regarded as an effective technique that provides a structured way to help people to produce creative ideas and solutions. Although some neuroscience studies regarding creativity training have been conducted, no study has focused on SCAMPER. This study therefore aimed at examining whether the learning of SCAMPER through video tutorials would result in alternations of neural activation. Thirty college students were randomly assigned to the experimental group or the control group. The experimental group was requested to watch SCAMPER videos, whereas the control group was asked to watch natural-scene videos which were regarded as neutral stimulating materials. Each participant was brain scanned in a Functional magnetic resonance imaging (fMRI) machine while undertaking a creativity test before and after watching the videos. Furthermore, a two-way ANOVA was used to analyze the interaction between groups (the experimental group; the control group) and tasks (C task; M task; X task). The results revealed that the left precuneus significantly activated in the interaction of groups and tasks, as well as in the main effect of group. Furthermore, compared with the control group, the experimental group had greater activation in the default mode network (left precuneus and left inferior parietal cortex) and the motor network (left postcentral gyrus and left supplementary area). The findings suggest that the SCAMPER training may facilitate creativity through the stimulation of the default mode network and the motor network.Keywords: creativity, default mode network, neural activation, SCAMPER
Procedia PDF Downloads 1006822 Numerical Analysis of Laminar Reflux Condensation from Gas-Vapour Mixtures in Vertical Parallel Plate Channels
Authors: Foad Hassaninejadafarahani, Scott Ormiston
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Reflux condensation occurs in a vertical channels and tubes when there is an upward core flow of vapor (or gas-vapor mixture) and a downward flow of the liquid film. The understanding of this condensation configuration is crucial in the design of reflux condensers, distillation columns, and in loss-of-coolant safety analyses in nuclear power plant steam generators. The unique feature of this flow is the upward flow of the vapor-gas mixture (or pure vapor) that retards the liquid flow via shear at the liquid-mixture interface. The present model solves the full, elliptic governing equations in both the film and the gas-vapor core flow. The computational mesh is non-orthogonal and adapts dynamically the phase interface, thus produces sharp and accurate interface. Shear forces and heat and mass transfer at the interface are accounted for fundamentally. This modeling is a big step ahead of current capabilities by removing the limitations of previous reflux condensation models which inherently cannot account for the detailed local balances of shear, mass, and heat transfer at the interface. Discretisation has been done based on a finite volume method and a co-located variable storage scheme. An in-house computer code was developed to implement the numerical solution scheme. Detailed results are presented for laminar reflux condensation from steam-air mixtures flowing in vertical parallel plate channels. The results include velocity and pressure profiles, as well as axial variations of film thickness, Nusselt number and interface gas mass fraction.Keywords: Reflux, Condensation, CFD-Two Phase, Nusselt number
Procedia PDF Downloads 3646821 Optimisation of Metrological Inspection of a Developmental Aeroengine Disc
Authors: Suneel Kumar, Nanda Kumar J. Sreelal Sreedhar, Suchibrata Sen, V. Muralidharan,
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Fan technology is very critical and crucial for any aero engine technology. The fan disc forms a critical part of the fan module. It is an airworthiness requirement to have a metrological qualified quality disc. The current study uses a tactile probing and scanning on an articulated measuring machine (AMM), a bridge type coordinate measuring machine (CMM) and Metrology software for intermediate and final dimensional and geometrical verification during the prototype development of the disc manufactured through forging and machining process. The circumferential dovetails manufactured through the milling process are evaluated based on the evaluated and analysed metrological process. To perform metrological optimization a change of philosophy is needed making quality measurements available as fast as possible to improve process knowledge and accelerate the process but with accuracy, precise and traceable measurements. The offline CMM programming for inspection and optimisation of the CMM inspection plan are crucial portions of the study and discussed. The dimensional measurement plan as per the ASME B 89.7.2 standard to reach an optimised CMM measurement plan and strategy are an important requirement. The probing strategy, stylus configuration, and approximation strategy effects on the measurements of circumferential dovetail measurements of the developmental prototype disc are discussed. The results were discussed in the form of enhancement of the R &R (repeatability and reproducibility) values with uncertainty levels within the desired limits. The findings from the measurement strategy adopted for disc dovetail evaluation and inspection time optimisation are discussed with the help of various analyses and graphical outputs obtained from the verification process.Keywords: coordinate measuring machine, CMM, aero engine, articulated measuring machine, fan disc
Procedia PDF Downloads 1076820 Conciliation Bodies as an Effective Tool for the Enforcement of Air Passenger Rights: Examination of an Exemplary Model in Germany
Authors: C. Hipp
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The EU Regulation (EC) No 261/2004 under which air passengers can claim compensation in the event of denied boarding, cancellation or long delay of flights has to be regarded as a substantial progress for the consumer protection in the field of air transport since it went into force in February 2005. Nevertheless, different reviews of its effective functioning demonstrate that most passengers affected by service disruptions do not enforce their complaints and claims towards the airline. The main cause of this is not only the unclear legal situation due to the fact that the regulation itself suffers from many undetermined terms and loopholes it is also attributable to the strategy of the airlines which do not handle the complaints of the passengers or exclude their duty to compensate them. Economically contemplated, reasons like the long duration of a trial and the cost risk in relation to the amount of compensation make it comprehensible that passengers are deterred from enforcing their rights by filing a lawsuit. The paper focusses on the alternative dispute resolution namely the recently established conciliation bodies which deal with air passenger rights. In this paper, the Conciliation Body for Public Transport in Germany (Schlichtungsstelle für den öffentlichen Personenverkehr – SÖP) is examined as a successful example of independent consumer arbitration service. It was founded in 2009 and deals with complaints in the field of air passenger rights since November 2013. According to the current situation one has to admit that due to its structure and operation it meets on the one hand the needs of the airlines by giving them an efficient tool of their customer relation management and on the other hand that it contributes to the enforcement of air passenger rights effectively.Keywords: air passenger rights, alternative dispute resolution, consumer protection, EU law regulation (EC) 261/2004
Procedia PDF Downloads 2306819 Designing Agricultural Irrigation Systems Using Drone Technology and Geospatial Analysis
Authors: Yongqin Zhang, John Lett
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Geospatial technologies have been increasingly used in agriculture for various applications and purposes in recent years. Unmanned aerial vehicles (drones) fit the needs of farmers in farming operations, from field spraying to grow cycles and crop health. In this research, we conducted a practical research project that used drone technology to design and map optimal locations and layouts of irrigation systems for agriculture farms. We flew a DJI Mavic 2 Pro drone to acquire aerial remote sensing images over two agriculture fields in Forest, Mississippi, in 2022. Flight plans were first designed to capture multiple high-resolution images via a 20-megapixel RGB camera mounted on the drone over the agriculture fields. The Drone Deploy web application was then utilized to develop flight plans and subsequent image processing and measurements. The images were orthorectified and processed to estimate the area of the area and measure the locations of the water line and sprinkle heads. Field measurements were conducted to measure the ground targets and validate the aerial measurements. Geospatial analysis and photogrammetric measurements were performed for the study area to determine optimal layout and quantitative estimates for irrigation systems. We created maps and tabular estimates to demonstrate the locations, spacing, amount, and layout of sprinkler heads and water lines to cover the agricultural fields. This research project provides scientific guidance to Mississippi farmers for a precision agricultural irrigation practice.Keywords: drone images, agriculture, irrigation, geospatial analysis, photogrammetric measurements
Procedia PDF Downloads 766818 Porphyry Cu-Mo-(Au) Mineralization at Paraga Area, Nakhchivan District, Azerbaijan: Evidence from Mineral Paragenesis, Hyrothermal Alteration and Geochemical Studies
Authors: M. Kumral, A. Abdelnasser, M. Budakoglu, M. Karaman, D. K. Yildirim, Z. Doner, A. Bostanci
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The Paraga area is located at the extreme eastern part of Nakhchivan district at the boundary with Armenia. The field study is situated at Ordubad region placed in 9 km from Paraga village and stays at 2300-2800 m height over sea level. It lies within a region of low-grade metamorphic porphyritic volcanic and plutonic rocks. The detailed field studies revealed that this area composed mainly of metagabbro-diorite intrusive rocks with porphyritic character emplaced into meta-andesitic rocks. This complex is later intruded by unmapped olivine gabbroic rocks. The Cu-Mo-(Au) mineralization at Paraga deposit is vein-type mineralization that is essentially related to quartz veins stockwork which cut the dioritic rocks and concentrated at the eastern and northeastern parts of the area with different directions N80W, N25W, N70E and N45E. Also, this mineralization is associated with two shearing zones directed N75W and N15E. The host porphyritic rocks were affected by intense sulfidation, carbonatization, sericitization and silicification with pervasive hematitic alterations accompanied with mineralized quartz veins and quartz-carbonate veins. Sulfide minerals which are chalcopyrite, pyrite, arsenopyrite and sphalerite occurred in two cases either inside these mineralized quartz veins or disseminated in the highly altered rocks as well as molybdenite and also at the peripheries between the altered host rock and veins. Gold found as inclusion disseminated in arsenopyrite and pyrite as well as in their cracks.Keywords: porphyry Cu-Mo-(Au), Paraga area, Nakhchivan, Azerbaijan, paragenesis, hyrothermal alteration
Procedia PDF Downloads 4086817 Modulating Plasmon Induced Transparency in Terahertz Metamaterials
Authors: Gagan Kumar, Koijam M. Devi, Amarendra K. Sarma, Dibakar Roy Chowdhury
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Research in metamaterials has been gaining momentum over the past decade owing to its ability in controlling electromagnetic wave properties through careful design at the sub-wavelength scale. The metamaterials have led to several important phenomena which are useful in a variety of applications. One such phenomenon is the electromagnetically induced transparency (EIT) effect in which a narrow transparency region is created in an otherwise absorptive spectrum. In our work, we explore plasmon induced transparency (PIT) in terahertz metamaterials which is analogues to EIT effect. The PIT effect is achieved using the plasmonic metamaterials in which a unit cell is comprised of two C (2C) shaped resonators and a cut-wire (CW). When terahertz wave of a particular polarization is normally incident on the proposed metamaterials geometry, it strongly couples with the cut wire, resulting in the excitation of the bright mode. However due to the specific polarization of the incident beam, the fundamental modes of the C-shaped resonators are not excited by the incident terahertz, hence they are termed as the dark mode. The PIT effect occurs as a result of interference between the bright and the dark mode. In order to observe PIT effect, both the bright and dark modes should have similar resonant frequencies with a little deviation. We further have examined that the PIT window can be modulated by displacing the C-shaped resonators w.r.t. the cut-wire. The numerical observations for different coupling configurations can be explained through an equivalent lumped element circuit model. Moving ahead the PIT effect is further explored in a metamaterial comprising of a cross like structure and four C-shaped resonators. For such configuration, equally strong PIT effect is observed for two orthogonally polarized lights. Therefore, such metamaterials demonstrate a polarization independent PIT response w.r.t the incident terahertz radiation. The proposed study could be significant in the development of slow light devices and polarization independent sensing applications.Keywords: terahertz, metamaterial, split ring resonator, plasmon
Procedia PDF Downloads 2136816 Relationships between Chinese Talented Educated Women
Authors: Jianghe Niu, Zhu Xiao Di
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This research uses a qualitative case study of the literature review approach to explore and analyze the relationship between three pairs of famous and talented women in China and uncovers certain regularities. From all kinds of available Chinese materials, such as biographies, memoirs, and news reports, both in papers and from the internet, we carefully selected the following 3 pairs of 6 Chinese women, whose relationships went through upheavals from friendship to jealousy and hostility, and we analyzed many factors contributing to this kind of relationship. (1) Hong Huang and Su Mang, both are leaders in the contemporary Chinese fashion industry as editors-in-chief of major fashion magazines. (2) Lin Huiyin and Xie Bingxin, both are phenomenally successful women in the field of literature and/or architecture throughout most of the 20th century. They are also quite similar in terms of age, family background, professional achievements, and celebrity status, but the former has multiple men's pursuit and admiration, while the latter has fewer. (3) Zhang Ailing and Su Qing, their achievements in the field of literature are remarkably similar, as top two female authors in metropolitan Shanghai during 1940s. They once admired each other's talents very much. Zhang’s husband used to have a relationship with Su Qing, and it was through Su Qing that he met Zhang Ailing. Major Findings: (1) Across the three pairs of case studies, it is observed that the more they are similar to each other in age, family background, education level, career positions, and social statues, the more they are likely to be in discord, jealousy, and hostility. (2) In the relationship between Chinese women, especially between talented, educated women, if there are men involved and one is more adored and favored by men than the other, such as in the 2nd and third pairs, the resulting jealousy deepens the negative relationship between them. (3) The relationship between talented and successful Chinese women, as shown in the third example, where a man was introduced by a woman to her close female friend, and then the man fell in love with her and married her, would undoubtedly deteriorate until jealousy, hatred, and hostility reached climax.Keywords: relationship, Chinese, women, men
Procedia PDF Downloads 866815 Status of Mangrove Wetlands and Implications for Sustainable Livelihood of Coastal Communities on the Lagos Coast (West Africa)
Authors: I. Agboola Julius, Christopher A. Kumolu-Johnson, O. Kolade Rafiu, A. Saba Abdulwakil
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This work elucidates on mangrove diversity, trends of change, factors responsible for loss over the years and implications for sustainable livelihoods of locals in four villages (Ajido (L1), Tarkwa bay (L2), University of Lagos (L3), and Ikosi (L4)) along the coast of Lagos, Nigeria. Primary data were collected through field survey, questionnaires, interviews, and review of existing literature. Field observation and data analysis reveals mangrove diversity as low and varied on a spatial scale, where Margalef’s Diversity Index (D) was 0.368, 0.269, 0.326, and 0.333, respectively for L1, L2, L3, and L4. Shannon Weiner’s Index (H) was estimated to be 1.003, 1.460, 1.160, 1.046, and Specie Richness (E) 0.913, 0.907, 0.858, and 0.015, respectively, for the four villages. Also, The Simpson’s index of diversity was analyzed to be 0.632, 0. 731, 0.647, 0.667, and Simpson’s reciprocal index 2.717, 3.717, 3.060, and 3.003, respectively, for the four villages. Chi-square test was used to analyze the impact of mangrove loss on the sustainable livelihood of coastal communities. Calculated Chi-square (X2) value (5) was higher than tabulated value (4.30), suggesting that loss of mangrove wetlands impacted on local communities’ livelihood at the four villages. Analyses of causes and trends of mangrove wetland loss over the years suggest that urbanization, fuel wood and agricultural activities are major causes. Current degradation observed in mangrove wetlands on the Lagos coast suggest a reduction in mangroves biodiversity and associated fauna with potential cascading effects on higher trophic levels such as fisheries. Low yield in fish catch, reduction in income and increasing cases of natural disaster has culminated in threats to sustainable livelihoods of local communities along the coast of Lagos.Keywords: Mangroves, lagos coast, fisheries, management
Procedia PDF Downloads 6476814 A National Survey of Clinical Psychology Graduate Student Attitudes toward Psychotherapy Treatment Manuals: A Replication Study
Authors: B. Bergström, A. Ladd, A. Jones, L. Rosso, P. Michael
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Attitudes toward treatment manuals serve as a meaningful predictor of general attitudes toward evidence-based practice. Despite demonstrating high effectiveness in treating many mental disorders, manualized treatments have been underutilized by practitioners. Thus, one can assess the state of the field regarding the adoption of evidence-based practices by surveying practitioner attitudes towards manualized treatments. This study is an adapted replication that assesses psychology graduate student attitudes towards manualized treatments, as a general marker for attitudes towards evidence-based practice. Training programs provide future clinicians with the foundation for critical skills in clinical practice. Research demonstrates that post-graduate continuing education has little to no effect on clinical practice; thus, graduate programs serve as the primary, and often final platform for all future practice. However, there are little empirical data identifying the attitudes and training of graduate students in utilizing manualized treatments. The empirical analysis of this study indicates an increase in positive attitudes among graduate student attitudes towards manualized treatments (within the United States), when compared to past surveys of professional psychologists. Findings from this study may inform graduate programs of barriers for students in developing positive attitudes toward manualized treatments and evidence-based practice. This study also serves as a preliminary predictor of the state-of-the field, in regards to professional psychologists attitudes towards evidence-based practice, if attitudes remain stable. This study indicates that the attitudes toward utilizing evidence-based practices, such as treatment manuals, has become more positive since year 2000.Keywords: exposure therapy, evidence based practice, manualized treatments, student attitudes
Procedia PDF Downloads 1636813 Studying the Effect of Carbon Nanotubes on the Mechanical Properties of Epoxy-Nanocomposite for the Oil Field Applications
Authors: Mohammed Al-Bahrani, Alistair Cree, Zoltan J. Gombos
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Carbon nanotubes are currently considered to be one of the strongest and stiffest engineering materials available, possessing a calculated tensile strength of σTS ≈ 200GPa and Young’s moduli up to E = 1.4 TPa. In the context of manufactured engineering composites, epoxy resin is the most commonly used matrix material for many aerospace and oil field, and other, industrial applications. This paper reports the initial findings of a study which considered the effects that small additions of nickel coated multi-wall carbon nanotubes (Ni-MWCNTs) would have on the mechanical properties of an epoxy resin matrix material. To successfully incorporate these particles into the matrix materials, with good dispersive properties, standard mixing techniques using an ultrasonic bath were used during the manufacture of appropriate specimens for testing. The tensile and flexural strength properties of these specimens, as well as the microstructure, were then evaluated and studied. Scanning Electronics Microscope (SEM) was used to visualise the degree of dispersion of the Ni-MWCNT’s in matrix. The results obtained indicated that the mechanical properties of epoxy resin can be improved significantly by the addition of the Ni-MWCNT’s. Further, the addition of Ni-MWCNT’s increased the tensile strength by approximately 19% and the tensile modulus by 28%. The flexural strength increased by 20.7% and flexural modulus by 22.6% compared to unmodified epoxy resin. It is suggested that these improvements, seen with the Ni-MWCNT’s particles, were due to an increase in the degree of interfacial bonding between Ni-MWCNT and epoxy, so leading to the improved mechanical properties of the nanocomposite observed. Theoretical modelling, using ANSYS finite element analysis, also showed good correlation with the experimental results obtained.Keywords: carbon nanotubes, nanocomposite, epoxy resin, ansys
Procedia PDF Downloads 1746812 Research on Construction of Subject Knowledge Base Based on Literature Knowledge Extraction
Authors: Yumeng Ma, Fang Wang, Jinxia Huang
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Researchers put forward higher requirements for efficient acquisition and utilization of domain knowledge in the big data era. As literature is an effective way for researchers to quickly and accurately understand the research situation in their field, the knowledge discovery based on literature has become a new research method. As a tool to organize and manage knowledge in a specific domain, the subject knowledge base can be used to mine and present the knowledge behind the literature to meet the users' personalized needs. This study designs the construction route of the subject knowledge base for specific research problems. Information extraction method based on knowledge engineering is adopted. Firstly, the subject knowledge model is built through the abstraction of the research elements. Then under the guidance of the knowledge model, extraction rules of knowledge points are compiled to analyze, extract and correlate entities, relations, and attributes in literature. Finally, a database platform based on this structured knowledge is developed that can provide a variety of services such as knowledge retrieval, knowledge browsing, knowledge q&a, and visualization correlation. Taking the construction practices in the field of activating blood circulation and removing stasis as an example, this study analyzes how to construct subject knowledge base based on literature knowledge extraction. As the system functional test shows, this subject knowledge base can realize the expected service scenarios such as a quick query of knowledge, related discovery of knowledge and literature, knowledge organization. As this study enables subject knowledge base to help researchers locate and acquire deep domain knowledge quickly and accurately, it provides a transformation mode of knowledge resource construction and personalized precision knowledge services in the data-intensive research environment.Keywords: knowledge model, literature knowledge extraction, precision knowledge services, subject knowledge base
Procedia PDF Downloads 1636811 In-Service Training to Enhance Community Based Corrections
Authors: Varathagowry Vasudevan
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This paper attempts to demonstrate the importance of capacity building of the para-professionals in community based corrections for enhancing family and child welfare as a crucial factor in providing in-service training as a responsive methodology in community based corrections to enhance the best practices. The Diploma programme in community-based corrections initiated by the National Institute of Social Development has been engaged in this noble task of training quality personnel knowledgeable in the best practices and fieldwork skills on community-based correction and its best practice. To protect the families and children and enhance best practices, National Institute of Social Development with support from the department of community-based corrections initiated a Diploma programme in community-based corrections to enhance and update the knowledge, skills, attitudes with the right mindset of the work supervisors employed at the department of community-based corrections. This study based on reflective practice illustrated the effectiveness of curriculum of in-service training programme as a tool to enhance the capacities of the relevant officers in Sri Lanka. The data for the study was obtained from participants and coordinator through classroom discussions and key informant interviews. This study showed that use of appropriate tailor-made curriculum and field practice manual by the officers during the training was very much dependent on the provision of appropriate administrative facilities, passion, teaching methodology that promote capacity to involve best practices. It also demonstrated further the fact that professional social work response, strengthening families within legal framework was very much grounded in the adoption of proper skills imbibed through training in appropriate methodology practiced in the field under guided supervision.Keywords: capacity building, community-based corrections, in-service training, paraprofessionals
Procedia PDF Downloads 1566810 Impact of Entrepreneurship Education on Entrepreneurial Intention: A Case Study of Al Akhawayn University
Authors: Sara atibi, Azzeddine Atibi, Salim Ahmed, Khadija El Kababi
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Given the crucial impact of entrepreneurship on socio-economic development, nations are making various efforts to support and encourage it. Entrepreneurship education has proven to be a vital lever in stimulating business creation. This research is part of this dynamic, which is increasingly attracting the attention of educational policymakers. Indeed, entrepreneurship education provides students with the skills, knowledge, and motivation needed to succeed in various entrepreneurial contexts. it objective is to demonstrate the impact of entrepreneurship education on the development of entrepreneurial intention among students at Al Akhawayn University and to determine whether introducing this discipline at the secondary school level can strengthen this intention, with the aim of proposing measures to foster entrepreneurship. To achieve this objective, it conducted a literature review on entrepreneurship, entrepreneurial intention, and entrepreneurship education to draw from existing experiences in the field. it then carried out an exploratory study through a qualitative survey. it collected real data via an online questionnaire hosted on Google Drive. This questionnaire was tested on a sample of 100 students, adjusted, and validated by three university professors who are experts in the field, and then administered to the students of Al Akhawayn University. The results of our survey among students at Al Akhawayn University clearly show that the development of entrepreneurial intention increases among students who have taken entrepreneurship courses or participated in seminars, thus promoting business creation and entrepreneurship. A minority of these students still choose to work in the private or public sector; however, the majority express a strong desire to become entrepreneurs. We also noted that some students believe entrepreneurship depends solely on entrepreneurial training, while others think it relies on a combination of training, resources, and personal will.Keywords: entrepreneurship education, entrepreneurial intention, business creation, al akhawayn university, secondary school curriculum
Procedia PDF Downloads 346809 Fabrication of Hybrid Scaffolds Consisting of Cell-laden Electrospun Micro/Nanofibers and PCL Micro-structures for Tissue Regeneration
Authors: MyungGu Yeo, JongHan Ha, Gi-Hoon Yang, JaeYoon Lee, SeungHyun Ahn, Hyeongjin Lee, HoJun Jeon, YongBok Kim, Minseong Kim, GeunHyung Kim
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Tissue engineering is a rapidly growing interdisciplinary research area that may provide options for treating damaged tissues and organs. As a promising technique for regenerating various tissues, this technology requires biomedical scaffolds, which serve as an artificial extracellular matrix (ECM) to support neotissue growth. Electrospun micro/nanofibers have been used widely in tissue engineering because of their high surface-area-to-volume ratio and structural similarity to extracellular matrix. However, low mechanical sustainability, low 3D shape-ability, and low cell infiltration have been major limitations to their use. In this work, we propose new hybrid scaffolds interlayered with cell-laden electrospun micro/nano fibers and poly(caprolactone) microstructures. Also, we applied various concentrations of alginate and electric field strengths to determine optimal conditions for the cell-electrospinning process. The combination of cell-laden bioink (2 ⅹ 10^5 osteoblast-like MG63 cells/mL, 2 wt% alginate, 2 wt% poly(ethylene oxide), and 0.7 wt% lecithin) and a 0.16 kV/mm electric field showed the highest cell viability and fiber formation in this process. Using these conditions and PCL microstructures, we achieved mechanically stable hybrid scaffolds. In addition, the cells embedded in the fibrous structure were viable and proliferated. We suggest that the cell-embedded hybrid scaffolds fabricated using the cell-electrospinning process may be useful for various soft- and hard-tissue regeneration applications.Keywords: bioink, cell-laden scaffold, micro/nanofibers, poly(caprolactone)
Procedia PDF Downloads 3806808 Event Related Brain Potentials Evoked by Carmen in Musicians and Dancers
Authors: Hanna Poikonen, Petri Toiviainen, Mari Tervaniemi
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Event-related potentials (ERPs) evoked by simple tones in the brain have been extensively studied. However, in reality the music surrounding us is spectrally and temporally complex and dynamic. Thus, the research using natural sounds is crucial in understanding the operation of the brain in its natural environment. Music is an excellent example of natural stimulation, which, in various forms, has always been an essential part of different cultures. In addition to sensory responses, music elicits vast cognitive and emotional processes in the brain. When compared to laymen, professional musicians have stronger ERP responses in processing individual musical features in simple tone sequences, such as changes in pitch, timbre and harmony. Here we show that the ERP responses evoked by rapid changes in individual musical features are more intense in musicians than in laymen, also while listening to long excerpts of the composition Carmen. Interestingly, for professional dancers, the amplitudes of the cognitive P300 response are weaker than for musicians but still stronger than for laymen. Also, the cognitive P300 latencies of musicians are significantly shorter whereas the latencies of laymen are significantly longer. In contrast, sensory N100 do not differ in amplitude or latency between musicians and laymen. These results, acquired from a novel ERP methodology for natural music, suggest that we can take the leap of studying the brain with long pieces of natural music also with the ERP method of electroencephalography (EEG), as has already been made with functional magnetic resonance (fMRI), as these two brain imaging devices complement each other.Keywords: electroencephalography, expertise, musical features, real-life music
Procedia PDF Downloads 4846807 Localization of Frontal and Temporal Speech Areas in Brain Tumor Patients by Their Structural Connections with Probabilistic Tractography
Authors: B.Shukir, H.Woo, P.Barzo, D.Kis
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Preoperative brain mapping in tumors involving the speech areas has an important role to reduce surgical risks. Functional magnetic resonance imaging (fMRI) is the gold standard method to localize cortical speech areas preoperatively, but its availability in clinical routine is difficult. Diffusion MRI based probabilistic tractography is available in head MRI. It’s used to segment cortical subregions by their structural connectivity. In our study, we used probabilistic tractography to localize the frontal and temporal cortical speech areas. 15 patients with left frontal tumor were enrolled to our study. Speech fMRI and diffusion MRI acquired preoperatively. The standard automated anatomical labelling atlas 3 (AAL3) cortical atlas used to define 76 left frontal and 118 left temporal potential speech areas. 4 types of tractography were run according to the structural connection of these regions to the left arcuate fascicle (FA) to localize those cortical areas which have speech functions: 1, frontal through FA; 2, frontal with FA; 3, temporal to FA; 4, temporal with FA connections were determined. Thresholds of 1%, 5%, 10% and 15% applied. At each level, the number of affected frontal and temporal regions by fMRI and tractography were defined, the sensitivity and specificity were calculated. At the level of 1% threshold showed the best results. Sensitivity was 61,631,4% and 67,1523,12%, specificity was 87,210,4% and 75,611,37% for frontal and temporal regions, respectively. From our study, we conclude that probabilistic tractography is a reliable preoperative technique to localize cortical speech areas. However, its results are not feasible that the neurosurgeon rely on during the operation.Keywords: brain mapping, brain tumor, fMRI, probabilistic tractography
Procedia PDF Downloads 1666806 Heavy Metal Adsorption from Synthetic Wastewater Using Agro Waste-Based Nanoparticles: A Comparative Study
Authors: Nomthandazo Precious Sibiya, Thembisile Patience Mahlangu, Sudesh Rathilal
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Heavy metal removal is critical in the wastewater treatment process due to its numerous harmful effects on human and aquatic life. There are several chemical and physical techniques for removing heavy metals from wastewater, including ion exchange, reverse osmosis, adsorption, electrodialysis, and ultrafiltration. However, adsorption technology has captivated researchers for years due to its low cost, high efficiency, and compatible with the environment. In this study, the adsorption effectiveness of three modified agro-waste materials was explored for the removal of lead from synthetic wastewater: banana peels (BP), orange peels (OP), and sugarcane bagasse (SB). The magnetite (Fe₃O₄) is incorporated with BP, OP, and SB at a ratio of 1:1 to create magnetic biosorbents. Characterization of biosorbents was carried out using and scanning electron microscopy (SEM) combined with energy-dispersive X-ray (EDX) to investigate surface morphology and elemental compositions, respectively. A series of batch experiments were carried out to investigate the effects of adsorbent mass, agitation time, and initial pH concentration on adsorption behaviour, as well as adsorption isotherms and kinetics. The removal efficiency of lead by the modified agro-waste materials proved to be superior to that of non-modified agro-waste materials. The proof of concept was achieved, and agro-waste materials can be paired with adsorption technology to effectively remove lead from aqueous media. The use of agricultural waste as biosorbents will aid in waste reduction and management.Keywords: adsorption, isotherms, kinetics, agro waste, nanoparticles, batch
Procedia PDF Downloads 676805 Testing of Complicated Bus Bar Protection Using Smart Testing Methodology
Authors: K. N. Dinesh Babu
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In this paper, the protection of a complicated bus arrangement with a dual bus coupler and bus sectionalizer using low impedance differential protection applicable for very high voltages like 220kV and 400kV is discussed. In many power generation stations, several operational procedures are implemented to utilize the transfer bus as the main bus and to facilitate the maintenance of circuit breakers and current transformers (in each section) without shutting down the bay(s). Owing to this fact, the complications in operational philosophy have thrown challenges for the bus bar protection implementation. Many bus topologies allow any one of the main buses available in the station to be used as an auxiliary bus. In such a system, pre-defined precautions and procedures are made as guidelines, which are followed before assigning any bus as an auxiliary bus. The procedure involves shifting of links, changing rotary switches, insertion of test block, and so on, thereby causing unreliable operation. This kind of unreliable operation or inadvertent procedural lapse may result in the isolation of the bus bar from the grid due to the unpredictable operation of the bus bar protection relay, which is a commonly occurring phenomenon due to manual mistakes. With the sophisticated configuration and implementation of logic in modern intelligent electronic devices, the operator is free to select the transfer arrangement without sacrificing the protection required by a bus differential system for a reliable operation, and labor-intensive processes are completely eliminated. This paper deals with the procedure to test the security logic for such special scenarios using Megger make SMRT, bus bar protection relay to assure system stability and get rid of all the specific operational precautions/procedure.Keywords: bus bar protection, by-pass isolator, blind spot, breaker failure, intelligent electronic device, end fault, bus unification, directional principle, zones of protection, breaker re-trip, under voltage security, smart megger relay tester
Procedia PDF Downloads 686804 The International Classification of Functioning, Disability and Health (ICF) as a Problem-Solving Tool in Disability Rehabilitation and Education Alliance in Metabolic Disorders (DREAM) at Sultan Bin Abdul Aziz Humanitarian City:A Prototype for Reh
Authors: Hamzeh Awad
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Disability is considered to be a worldwide complex phenomenon which rising at a phenomenal rate and caused by many different factors. Chronic diseases such as cardiovascular disease and diabetes can lead to mobility disability in particular and disability in general. The ICF is an integrative bio-psycho-social model of functioning and disability and considered by the World Health Organization (WHO) to be a reference for disability classification using its categories and core set to classify disorder’s functional limitations. Specialist programs at Sultan Bin Abdul Aziz Humanitarian City (SBAHC) are providing both inpatient and outpatient services have started to implement the ICF and use it as a problem solving tool in Rehab. Diabetes is leading contributing factor for disability and considered epidemic in several Gulf countries including the Kingdom of Saudi Arabia (KSA), where its prevalence continues to increase dramatically. Metabolic disorders, mainly diabetes are not well covered in Rehab field. The purpose of this study is present to research and clinical rehabilitation field of DREAM and ICF as a framework in clinical and research setting in Rehab service. Also, shed the light on using the ICF as problem solving tool at SBAHC. There are synergies between disability causes and wider public health priorities in relation to both chronic disease and disability prevention. Therefore, there is a need for strong advocacy and understanding of the role of ICF as a reference in Rehab settings in Middle East if we wish to seize the opportunity to reverse current trends of acquired disability in the region.Keywords: international classification of functioning, disability and health (ICF), prototype, rehabilitation and diabetes
Procedia PDF Downloads 3516803 Modifications in Design of Lap Joint of Fiber Metal Laminates
Authors: Shaher Bano, Samia Fida, Asif Israr
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The continuous development and exploitation of materials and designs have diverted the attention of the world towards the use of robust composite materials known as fiber-metal laminates in many high-performance applications. The hybrid structure of fiber metal laminates makes them a material of choice for various applications such as aircraft skin panels, fuselage floorings, door panels and other load bearing applications. The synergistic effect of properties of metals and fibers reinforced laminates are responsible for their high damage tolerance as the metal element provides better fatigue and impact properties, while high stiffness and better corrosion properties are inherited from the fiber reinforced matrix systems. They are mostly used as a layered structure in different joint configurations such as lap and but joints. The FML layers are usually bonded with each other using either mechanical fasteners or adhesive bonds. This research work is also focused on modification of an adhesive bonded joint as a single lap joint of carbon fibers based CARALL FML has been modified to increase interlaminar shear strength and avoid delamination. For this purpose different joint modification techniques such as the introduction of spews and shoulder to modify the bond shape and use of nanofillers such as carbon nano-tubes as a reinforcement in the adhesive materials, have been utilized to improve shear strength of lap joint of the adhesively bonded FML layers. Both the simulation and experimental results showed that lap joint with spews and shoulders configuration have better properties due to stress distribution over a large area at the corner of the joint. The introduction of carbon nanotubes has also shown a positive effect on shear stress and joint strength as they act as reinforcement in the adhesive bond material.Keywords: adhesive joint, Carbon Reinforced Aluminium Laminate (CARALL), fiber metal laminates, spews
Procedia PDF Downloads 2996802 Design of an Acoustic Imaging Sensor Array for Mobile Robots
Authors: Dibyendu Roy, V. Ramu Reddy, Parijat Deshpande, Ranjan Dasgupta
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Imaging of underwater objects is primarily conducted by acoustic imagery due to the severe attenuation of electro-magnetic waves in water. Acoustic imagery underwater has varied range of significant applications such as side-scan sonar, mine hunting sonar. It also finds utility in other domains such as imaging of body tissues via ultrasonography and non-destructive testing of objects. In this paper, we explore the feasibility of using active acoustic imagery in air and simulate phased array beamforming techniques available in literature for various array designs to achieve a suitable acoustic sensor array design for a portable mobile robot which can be applied to detect the presence/absence of anomalous objects in a room. The multi-path reflection effects especially in enclosed rooms and environmental noise factors are currently not simulated and will be dealt with during the experimental phase. The related hardware is designed with the same feasibility criterion that the developed system needs to be deployed on a portable mobile robot. There is a trade of between image resolution and range with the array size, number of elements and the imaging frequency and has to be iteratively simulated to achieve the desired acoustic sensor array design. The designed acoustic imaging array system is to be mounted on a portable mobile robot and targeted for use in surveillance missions for intruder alerts and imaging objects during dark and smoky scenarios where conventional optic based systems do not function well.Keywords: acoustic sensor array, acoustic imagery, anomaly detection, phased array beamforming
Procedia PDF Downloads 4096801 Liquid Biopsy and Screening Biomarkers in Glioma Grading
Authors: Abdullah Abdu Qaseem Shamsan
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Background: Gliomas represent the most frequent, heterogeneous group of tumors arising from glial cells, characterized by difficult monitoring, poor prognosis, and fatality. Tissue biopsy is an established procedure for tumor cell sampling that aids diagnosis, tumor grading, and prediction of prognosis. We studied and compared the levels of liquid biopsy markers in patients with different grades of glioma. Also, it tried to establish the potential association between glioma and specific blood groups antigen. Result: 78 patients were identified, among whom maximum percentage with glioblastoma possessed blood group O+ (53.8%). The second highest frequency had blood group A+ (20.4%), followed by B+ (9.0%) and A- (5.1%), and least with O-. Liquid biopsy biomarkers comprised of ALT, LDH, lymphocytes, Urea, Alkaline phosphatase, AST Neutrophils, and CRP. The levels of all the components increased significantly with the severity of glioma, with maximum levels seen in glioblastoma (grade IV), followed by grade III and grade II respectively. Conclusion: Gliomas possess significant clinical challenges due to their progression with heterogeneous nature and aggressive behavior. Liquid biopsy is a non-invasive approach which aids to establish the status of the patient and determine the tumor grade, therefore may show diagnostic and prognostic utility. Additionally, our study provides evidence to demonstrate the role of ABO blood group antigens in the development of glioma. However, future clinical research on liquid biopsy will improve the sensitivity and specificity of these tests and validate their clinical usefulness to guide treatment approaches.Keywords: GBM: glioblastoma multiforme, CT: computed tomography, MRI: magnetic resonance imaging, ctRNA: circulating tumor RNA
Procedia PDF Downloads 51