Search results for: stationary measure
3240 Spherical Nonlinear Wave Propagation in Relativistic Quantum Plasma
Authors: Alireza Abdikian
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By assuming a quantum relativistic degenerate electron-positron (e-p) plasma media, the nonlinear acoustic solitary propagation in the presence of the stationary ions for neutralizing the plasma background of bounded cylindrical geometry was investigated. By using the standard reductive perturbation technique with cooperation the quantum hydrodynamics model for the e-p fluid, the spherical Kadomtsev-Petviashvili equation was derived for small but finite amplitude waves and was given the solitary wave solution for the parameters relevant for dense astrophysical objects such as white dwarf stars. By using a suitable coordinate transformation and using improved F-expansion technique, the SKP equation can be solved analytically. The numerical results reveal that the relativistic effects lead to propagate the electrostatic bell shape structures and by increasing the relativistic effects, the amplitude and the width of the e-p acoustic solitary wave will decrease.Keywords: Electron-positron plasma, Acoustic solitary wave, Relativistic plasmas, the spherical Kadomtsev-Petviashvili equation
Procedia PDF Downloads 1373239 Development and Psychometric Properties of the Dutch Contextual Assessment of Social Skills: A Blinded Observational Outcome Measure of Social Skills for Adolescents with Autism Spectrum Disorder
Authors: Sakinah Idris, Femke Ten Hoeve, Kirstin Greaves-Lord
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Background: Social skills interventions are considered to be efficacious if social skills are improved as a result of an intervention. Nevertheless, the objective assessment of social skills is hindered by a lack of sensitive and validated measures. To measure the change in social skills after an intervention, questionnaires reported by parents, clinicians and/or teachers are commonly used. Observations are the most ecologically valid method of assessing improvements in social skills after an intervention. For this purpose, The Program for the Educational and Enrichment of Relational Skills (PEERS) was developed for adolescents, in order to teach them the age-appropriate skills needed to participate in society. It is an evidence-based intervention for adolescents with ASD that taught ecologically valid social skills techniques. Objectives: The current study aims to describe the development and psychometric evaluation of the Dutch Contextual Assessment of Social Skills (CASS), an observational outcome measure of social skills for adolescents with Autism Spectrum Disorder (ASD). Methods: 64 adolescents (M = 14.68, SD = 1.41, 71% boys) with ASD performed the CASS before and after a social skills intervention (i.e. PEERS or the active control condition). Each adolescent completed a 3-minute conversation with a confederate. The conversation was prompt as a natural introduction between two-unfamiliar, similar ages, opposite-sex peers who meet for the first time. The adolescent and the confederate completed a brief questionnaire about the conversation (Conversation Rating Scale). Results: Results indicated sufficient psychometric properties. The Dutch CASS has a high level of internal consistency (Cronbach's α coefficients = 0.84). Data supported the convergent validity (i.e., significant correlated with the Social Skills Improvement System (SSiS). The Dutch CASS did not significantly correlate with the autistic mannerism subscale from Social Responsiveness Scale (SRS), thus proved the divergent validity. Based on scorings made by raters who were kept blind to the time points, reliable change index was computed to assess the change in social skills. With regard to the content validity, only the learning objectives of the first two meetings of PEERS about conversational skills relatively matched with rating domains of the CASS. Due to this underrepresentation, we found an existing observational measure (TOPICC) that covers some of the other learning objectives of PEERS. TOPICC covers 22% of the learning objectives of PEERS about conversational skills, meanwhile, CASS is 45%. Unfortunately, 33% of the learning objectives of PEERS was not covered by CASS or TOPICC. Conclusion: Recommendations are made to improve the psychometric properties and content validity of the Dutch CASS.Keywords: autism spectrum disorder, observational, PEERS, social skills
Procedia PDF Downloads 1443238 Implicit Transaction Costs and the Fundamental Theorems of Asset Pricing
Authors: Erindi Allaj
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This paper studies arbitrage pricing theory in financial markets with transaction costs. We extend the existing theory to include the more realistic possibility that the price at which the investors trade is dependent on the traded volume. The investors in the market always buy at the ask and sell at the bid price. Transaction costs are composed of two terms, one is able to capture the implicit transaction costs and the other the price impact. Moreover, a new definition of a self-financing portfolio is obtained. The self-financing condition suggests that continuous trading is possible, but is restricted to predictable trading strategies which have left and right limit and finite quadratic variation. That is, predictable trading strategies of infinite variation and of finite quadratic variation are allowed in our setting. Within this framework, the existence of an equivalent probability measure is equivalent to the absence of arbitrage opportunities, so that the first fundamental theorem of asset pricing (FFTAP) holds. It is also proved that, when this probability measure is unique, any contingent claim in the market is hedgeable in an L2-sense. The price of any contingent claim is equal to the risk-neutral price. To better understand how to apply the theory proposed we provide an example with linear transaction costs.Keywords: arbitrage pricing theory, transaction costs, fundamental theorems of arbitrage, financial markets
Procedia PDF Downloads 3503237 The Kinks, the Solitons, and the Shocks in Series Connected Discrete Josephson Transmission Lines
Authors: Eugene Kogan
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We analytically study the localized running waves in the discrete Josephson transmission lines (JTL), constructed from Josephson junctions (JJ) and capacitors. The quasi-continuum approximation reduces the calculation of the running wave properties to the problem of equilibrium of an elastic rod in the potential field. Making additional approximations, we reduce the problem to the motion of the fictitious Newtonian particle in the potential well. We show that there exist running waves in the form of supersonic kinks and solitons and calculate their velocities and profiles. We show that the nonstationary smooth waves, which are small perturbations on the homogeneous non-zero background, are described by Korteweg-de Vries equation, and those on zero background -by the modified Korteweg-de Vries equation. We also study the effect of dissipation on the running waves in JTL and find that in the presence of the resistors, shunting the JJ and/or in series with the ground capacitors, the only possible stationary running waves are the shock waves, whose profiles are also found.Keywords: Josephson transmission line, shocks, solitary waves, nonlinear waves
Procedia PDF Downloads 1113236 Designing of Induction Motor Efficiency Monitoring System
Authors: Ali Mamizadeh, Ires Iskender, Saeid Aghaei
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Energy is one of the important issues with high priority property in the world. Energy demand is rapidly increasing depending on the growing population and industry. The useable energy sources in the world will be insufficient to meet the need for energy. Therefore, the efficient and economical usage of energy sources is getting more importance. In a survey conducted among electric consuming machines, the electrical machines are consuming about 40% of the total electrical energy consumed by electrical devices and 96% of this consumption belongs to induction motors. Induction motors are the workhorses of industry and have very large application areas in industry and urban systems like water pumping and distribution systems, steel and paper industries and etc. Monitoring and the control of the motors have an important effect on the operating performance of the motor, driver selection and replacement strategy management of electrical machines. The sensorless monitoring system for monitoring and calculating efficiency of induction motors are studied in this study. The equivalent circuit of IEEE is used in the design of this study. The terminal current and voltage of induction motor are used in this motor to measure the efficiency of induction motor. The motor nameplate information and the measured current and voltage are used in this system to calculate accurately the losses of induction motor to calculate its input and output power. The efficiency of the induction motor is monitored online in the proposed method without disconnecting the motor from the driver and without adding any additional connection at the motor terminal box. The proposed monitoring system measure accurately the efficiency by including all losses without using torque meter and speed sensor. The monitoring system uses embedded architecture and does not need to connect to a computer to measure and log measured data. The conclusion regarding the efficiency, the accuracy and technical and economical benefits of the proposed method are presented. The experimental verification has been obtained on a 3 phase 1.1 kW, 2-pole induction motor. The proposed method can be used for optimal control of induction motors, efficiency monitoring and motor replacement strategy.Keywords: induction motor, efficiency, power losses, monitoring, embedded design
Procedia PDF Downloads 3413235 Desktop High-Speed Aerodynamics by Shallow Water Analogy in a Tin Box for Engineering Students
Authors: Etsuo Morishita
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In this paper, we show shallow water in a tin box as an analogous simulation tool for high-speed aerodynamics education and research. It is customary that we use a water tank to create shallow water flow. While a flow in a water tank is not necessarily uniform and is sometimes wavy, we can visualize a clear supercritical flow even when we move a body manually in stationary water in a simple shallow tin box. We can visualize a blunt shock wave around a moving circular cylinder together with a shock pattern around a diamond airfoil. Another interesting analogous experiment is a hydrodynamic shock tube with water and tea. We observe the contact surface clearly due to color difference of the two liquids those are invisible in the real gas dynamics experiment. We first revisit the similarities between high-speed aerodynamics and shallow water hydraulics. Several educational and research experiments are then introduced for engineering students. Shallow water experiments in a tin box simulate properly the high-speed flows.Keywords: aerodynamics compressible flow, gas dynamics, hydraulics, shock wave
Procedia PDF Downloads 2973234 Numerical Study of Heat Transfer Nanofluid TiO₂ through a Solar Flat Plate Collector
Authors: A. Maouassi, A. Beghidja, S. Daoud, N. Zeraibi
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This paper illustrates a practical application of nanoparticles (TiO₂) as working fluid to stimulate solar flat plate collector efficiency with heat transfer modification properties. A numerical study of nanofluids laminar forced convection, permanent and stationary, is conducted in a solar flat plate collector. The effectiveness of these nanofluids are compared to conventional working fluid (water), wherein the dynamic and thermal properties are evaluated for four volume concentrations of nanoparticles (1%, 3%, 5% and 10%), and this done for Reynolds number from 25 to 800. Results from the application of those nonfluids are obtained versus pressure drop coefficient and Nusselt number are discussed later in this paper. Finally, we concluded that the heat transfer increases with increasing both nanoparticles concentration and Reynolds number.Keywords: CFD, forced convection, nanofluid, solar flat plate collector efficiency, TiO₂ nanoparticles
Procedia PDF Downloads 1563233 Breast Cancer Diagnosing Based on Online Sequential Extreme Learning Machine Approach
Authors: Musatafa Abbas Abbood Albadr, Masri Ayob, Sabrina Tiun, Fahad Taha Al-Dhief, Mohammad Kamrul Hasan
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Breast Cancer (BC) is considered one of the most frequent reasons of cancer death in women between 40 to 55 ages. The BC is diagnosed by using digital images of the FNA (Fine Needle Aspirate) for both benign and malignant tumors of the breast mass. Therefore, this work proposes the Online Sequential Extreme Learning Machine (OSELM) algorithm for diagnosing BC by using the tumor features of the breast mass. The current work has used the Wisconsin Diagnosis Breast Cancer (WDBC) dataset, which contains 569 samples (i.e., 357 samples for benign class and 212 samples for malignant class). Further, numerous measurements of assessment were used in order to evaluate the proposed OSELM algorithm, such as specificity, precision, F-measure, accuracy, G-mean, MCC, and recall. According to the outcomes of the experiment, the highest performance of the proposed OSELM was accomplished with 97.66% accuracy, 98.39% recall, 95.31% precision, 97.25% specificity, 96.83% F-measure, 95.00% MCC, and 96.84% G-Mean. The proposed OSELM algorithm demonstrates promising results in diagnosing BC. Besides, the performance of the proposed OSELM algorithm was superior to all its comparatives with respect to the rate of classification.Keywords: breast cancer, machine learning, online sequential extreme learning machine, artificial intelligence
Procedia PDF Downloads 1033232 Concept Drifts Detection and Localisation in Process Mining
Authors: M. V. Manoj Kumar, Likewin Thomas, Annappa
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Process mining provides methods and techniques for analyzing event logs recorded in modern information systems that support real-world operations. While analyzing an event-log, state-of-the-art techniques available in process mining believe that the operational process as a static entity (stationary). This is not often the case due to the possibility of occurrence of a phenomenon called concept drift. During the period of execution, the process can experience concept drift and can evolve with respect to any of its associated perspectives exhibiting various patterns-of-change with a different pace. Work presented in this paper discusses the main aspects to consider while addressing concept drift phenomenon and proposes a method for detecting and localizing the sudden concept drifts in control-flow perspective of the process by using features extracted by processing the traces in the process log. Our experimental results are promising in the direction of efficiently detecting and localizing concept drift in the context of process mining research discipline.Keywords: abrupt drift, concept drift, sudden drift, control-flow perspective, detection and localization, process mining
Procedia PDF Downloads 3413231 Energy Use, Emissions, Economic Growth and Trade: Evidence from Mauritius
Authors: B. Seetanah, H. Neeliah
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This paper investigates the relationship among energy, emissions and economic growth in Mauritius in the presence of trade activities, with capital and labour as other control variables. Using annual data from 1960 to 2011, it is found that the variables are non-stationary and cointegrated. The relationship among the various variables are thus examined in a dynamic VECM framework. Our empirical results comply with the growth hypothesis. Output elasticities of 0.17, 0.25 and 0.43 show that increases in energy consumption cause increases in economic growth, capital accumulation and trade in the long run. We also found that CO2 negatively affects output, but has no significant effect on trade. Findings for the long-run generally tend to tally with those in the short-run. Interestingly we found that energy consumption has a significant impact on CO2 emissions. Our results tend to suggest that implementing energy conservation strategies to mitigate the negative impact of CO2 emissions can dent economic growth, and that promoting cleaner energy production could be a better alternative for Mauritius.Keywords: energy, emissions, economic growth, export, VECM
Procedia PDF Downloads 4713230 Tensile Force Estimation for Real-Size Pre-Stressed Concrete Girder using Embedded Elasto-Magnetic Sensor
Authors: Junkyeong Kim, Jooyoung Park, Aoqi Zhang, Seunghee Park
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The tensile force of Pre-Stressed Concrete (PSC) girder is the most important factor for evaluating the performance of PSC girder bridges. To measure the tensile force of PSC girder, several NDT methods were studied. However, conventional NDT method cannot be applied to the real-size PSC girder because the PS tendons could not be approached. To measure the tensile force of real-size PSC girder, this study proposed embedded EM sensor based tensile force estimation method. The embedded EM sensor could be installed inside of PSC girder as a sheath joint before the concrete casting. After curing process, the PS tendons were installed, and the tensile force was induced step by step using hydraulic jacking machine. The B-H loop was measured using embedded EM sensor at each tensile force steps and to compare with actual tensile force, the load cell was installed at each end of girder. The magnetization energy loss, that is the closed area of B-H loop, was decreased according to the increase of tensile force with regular pattern. Thus, the tensile force could be estimated by the tracking the change of magnetization energy loss of PS tendons. Through the experimental result, the proposed method can be used to estimate the tensile force of the in-situ real-size PSC girder bridge.Keywords: tensile force estimation, embedded EM sensor, magnetization energy loss, PSC girder
Procedia PDF Downloads 3303229 Disciplinary Procedures Used by Secondary School Teachers in Calabar Municipality, Nigeria
Authors: N. N. Nkomo, M. L. Mayanchi
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The present study investigated various forms of disciplinary procedures or punishment used by teachers in secondary schools in Calabar Municipality, Nigera. There are agitations amongst parents and educators on the use of corporal punishment as a disciplinary measure against children. Those against the use of corporal punishment argue that this form of punishment does not teach, it only terminates behaviour temporarily and inculcates violence. Those in support are of the view that corporal punishment serves as a deterrent to others. This study sought to find out the most common measure of discipline employed by teachers in private and public schools. The study had three objectives, three research questions and two hypotheses. The design of the present study was the ex-post facto descriptive survey, since variables under study were not manipulated by the researcher. Teachers in Calabar Municipal Secondary Schools formed the population. A sample of 160 teachers was used for the study. The data collection instrument was a facts finding questionnaire titled Disciplinary Procedures Inventory. Data collected were analyzed using simple percentages and chi-square. The major findings were that physical measures such as flogging, exercise/drills, and painful postures were commonly used by teachers in secondary schools. It was also found that these measures were more often used in public schools. It was recommended that teachers should rather employ non-violent techniques of discipline than physical punishment.Keywords: discipline, non-violent punishment, physical punishment, penalties, rewards
Procedia PDF Downloads 2163228 Inventory Policy with Continuous Price Reduction in Solar Photovoltaic Supply Chain
Authors: Xiangrong Liu, Chuanhui Xiong
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With the concern of large pollution emissions from coal-fired power plants and new commitment to green energy, global solar power industry was emerging recently. Due to the advanced technology, the price of solar photovoltaic(PV) module was reduced at a fast rate, which arose an interesting but challenge question to solar supply chain. This research is modeling the inventory strategies for a PV supply chain with a PV manufacturer, an assembler and an end customer. Through characterizing the manufacturer's and PV assembler's optimal decision in decentralized and centralized situation, this study shed light on how to improve supply chain performance through parameters setting in the contract design. The results suggest the assembler to lower the optimal stock level gradually each period before price reduction and set up a newsvendor base-stock policy in all periods after price reduction. As to the PV module manufacturer, a non-stationary produce-up-to policy is optimal.Keywords: photovoltaic, supply chain, inventory policy, base-stock policy
Procedia PDF Downloads 3443227 Modelling of Polymeric Fluid Flows between Two Coaxial Cylinders Taking into Account the Heat Dissipation
Authors: Alexander Blokhin, Ekaterina Kruglova, Boris Semisalov
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Mathematical model based on the mesoscopic theory of polymer dynamics is developed for numerical simulation of the flows of polymeric liquid between two coaxial cylinders. This model is a system of nonlinear partial differential equations written in the cylindrical coordinate system and coupled with the heat conduction equation including a specific dissipation term. The stationary flows similar to classical Poiseuille ones are considered, and the resolving equations for the velocity of flow and for the temperature are obtained. For solving them, a fast pseudospectral method is designed based on Chebyshev approximations, that enables one to simulate the flows through the channels with extremely small relative values of the radius of inner cylinder. The numerical analysis of the dependance of flow on this radius and on the values of dissipation constant is done.Keywords: dynamics of polymeric liquid, heat dissipation, singularly perturbed problem, pseudospectral method, Chebyshev polynomials, stabilization technique
Procedia PDF Downloads 2853226 A Quantitative Analysis for the Correlation between Corporate Financial and Social Performance
Authors: Wafaa Salah, Mostafa A. Salama, Jane Doe
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Recently, the corporate social performance (CSP) is not less important than the corporate financial performance (CFP). Debate still exists about the nature of the relationship between the CSP and CFP, whether it is a positive, negative or a neutral correlation. The objective of this study is to explore the relationship between corporate social responsibility (CSR) reports and CFP. The study uses the accounting-based and market-based quantitative measures to quantify the financial performance of seven organizations listed on the Egyptian Stock Exchange in 2007-2014. Then uses the information retrieval technologies to quantify the contribution of each of the three dimensions of the corporate social responsibility report (environmental, social and economic). Finally, the correlation between these two sets of variables is viewed together in a model to detect the correlations between them. This model is applied on seven firms that generate social responsibility reports. The results show a positive correlation between the Earnings per share (market based measure) and the economical dimension in the CSR report. On the other hand, total assets and property, plant and equipment (accounting-based measure) are positively correlated to the environmental and social dimensions of the CSR reports. While there is not any significant relationship between ROA, ROE, Operating income and corporate social responsibility. This study contributes to the literature by providing more clarification of the relationship between CFP and the isolated CSR activities in a developing country.Keywords: financial, social, machine learning, corporate social performance, corporate social responsibility
Procedia PDF Downloads 3053225 Quantitative and Qualitative Analysis of Randomized Controlled Trials in Physiotherapy from India
Authors: K. Hariohm, V. Prakash, J. Saravana Kumar
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Introduction and Rationale: Increased scope of Physiotherapy (PT) practice also has contributed to research in the field of PT. It is essential to determine the production and quality of the clinical trials from India since, it may reflect the scientific growth of the profession. These trends can be taken as a baseline to measure our performance and also can be used as a guideline for the future trials. Objective: To quantify and analyze qualitatively the RCT’s from India from the period 2000-2013’ May, and classify data for the information process. Methods: Studies were searched in the Medline database using the key terms “India”, “Indian”, “Physiotherapy”. Clinical trials only with PT authors were included. Trials out of scope of PT practice and on animals were excluded. Retrieved valid articles were analyzed for published year, type of participants, area of study, PEDro score, outcome measure domains of impairment, activity, participation; ‘a priori’ sample size calculation, region, and explanation of the intervention. Result: 45 valid articles were retrieved from the year 2000-2013’ May. The majority of articles were done on symptomatic participants (81%). The frequencies of conditions repeated more were low back pain (n-7) and diabetes (n-4). PEDro score with mode 5 and upper limit of 8 and lower limit 4 was found. 97.2% of studies measure the outcome at the impairment level, 34% in activity level, and 27.8% in participation level. 29.7% of studies did ‘a priori’ sample size calculation. Correlation of year trend and PEDro score found to be not significant (p>.05). Individual PEDro item analysis showed, randomization (100%), concealment (33%) baseline (76%), blinding-subject, therapist, assessor (9.1%, 0%, 10%), follow-up (89%) ITT (15%), statistics between groups (100%), measures of variance (88 %). Conclusion: The trend shows an upward slope in terms of RCTs published from India which is a good indicator. The qualitative analysis showed some gaps in the clinical trial design, which can be expected to be, fulfilled by the future researchers.Keywords: RCT, PEDro, physical therapy, rehabilitation
Procedia PDF Downloads 3373224 Variable Selection in a Data Envelopment Analysis Model by Multiple Proportions Comparison
Authors: Jirawan Jitthavech, Vichit Lorchirachoonkul
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A statistical procedure using multiple comparisons test for proportions is proposed for variable selection in a data envelopment analysis (DEA) model. The test statistic in the multiple comparisons is the proportion of efficient decision making units (DMUs) in a DEA model. Three methods of multiple comparisons test for proportions: multiple Z tests with Bonferroni correction, multiple tests in 2Xc crosstabulation and the Marascuilo procedure, are used in the proposed statistical procedure of iteratively eliminating the variables in a backward manner. Two simulation populations of moderately and lowly correlated variables are used to compare the results of the statistical procedure using three methods of multiple comparisons test for proportions with the hypothesis testing of the efficiency contribution measure. From the simulation results, it can be concluded that the proposed statistical procedure using multiple Z tests for proportions with Bonferroni correction clearly outperforms the proposed statistical procedure using the remaining two methods of multiple comparisons and the hypothesis testing of the efficiency contribution measure.Keywords: Bonferroni correction, efficient DMUs, Marascuilo procedure, Pastor et al. method, 2xc crosstabulation
Procedia PDF Downloads 3073223 Spherical Harmonic Based Monostatic Anisotropic Point Scatterer Model for RADAR Applications
Authors: Eric Huang, Coleman DeLude, Justin Romberg, Saibal Mukhopadhyay, Madhavan Swaminathan
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High performance computing (HPC) based emulators can be used to model the scattering from multiple stationary and moving targets for RADAR applications. These emulators rely on the RADAR Cross Section (RCS) of the targets being available in complex scenarios. Representing the RCS using tables generated from electromagnetic (EM) simulations is often times cumbersome leading to large storage requirement. This paper proposed a spherical harmonic based anisotropic scatterer model to represent the RCS of complex targets. The problem of finding the locations and reflection profiles of all scatterers can be formulated as a linear least square problem with a special sparsity constraint. This paper solves this problem using a modified Orthogonal Matching Pursuit algorithm. The results show that the spherical harmonic based scatterer model can effectively represent the RCS data of complex targets.Keywords: RADAR, RCS, high performance computing, point scatterer model
Procedia PDF Downloads 1853222 The Relationship between Self-Injury Behavior and Social Skills among Children with Mild Intellectual Disability in the State of Kuwait
Authors: Farah Al-Shatti, Elsayed El-Khamisi, Nabel Suleiman
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The study aimed at identifying the relationship between self-injury behavior and social skills among children with mild intellectual disability (ID) in the state of Kuwait. The sample of the study consisted of 65 males and females with ID; their ages ranged between 8 to 12 years. The study used a measure for rating self-injury behavior designed by the researcher; and a measure for rating social skills was designed. The results of the study showed that there was an increase in the percentages of the two dimensions of the self-injury behavior for children with ID; the self-injury behavior by child’s own body was higher than the self-injury behavior by environmental tools, additionally the results showed that there were statistically significant differences between males and females on the dimensions and total scorer of self-injury scale favor the males, and there were statistically significant differences between them on the dimensions of the social skills and total score favor the females, It also indicated that there was statistically significant negative relationship between the dimensions of the self-injury and the dimensions of the social skills for children with intellectual disability.Keywords: mild intellectual disability, self injury behavior, social skills, state of Kuwait
Procedia PDF Downloads 3453221 A Comparison of Computational and Experimental Data to Investigate the Influence of the Tangential Velocity of Inner Rotating Wall on Axial Velocity Profile of Flow through Vertical Annular Pipe with Rotating Inner Surface
Authors: Abdusalam Sharf
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In the oil and gas industries, one of the most important issues in drilling wells is understanding the behavior of a flow through an annulus gap in a vertical position, whose outer wall is stationary whilst the inner wall rotates. The main emphasis is placed on a comparison of experimental and computational investigations into the effects of the rotation speed of the inner pipe on the axial velocity profiles. The computational investigations were carried out by employing CFD software, and Gambit and Fluent. Three turbulence models were used: standard, RNG with enhanced wall treatment, and SST model. The profiles of the axial velocity had investigated at different rotation speeds of the inner pipe with three different volumetric flow rates. The comparison results showed that the calculations satisfactorily predict the qualitative features of the axial and swirl velocity profiles and the RNG model performs the best results.Keywords: computational fluid dynamics (CFD), SST k−ω shear-stress transport (k−ω mode variant), RNG k–ε renormalisation group (k−ε mode variant), y+ dimensionless distance from wall
Procedia PDF Downloads 3723220 Numerical Modeling of Air Pollution with PM-Particles and Dust
Authors: N. Gigauri, A. Surmava, L. Intskirveli, V. Kukhalashvili, S. Mdivani
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The subject of our study is atmospheric air pollution with numerical modeling. In the presented article, as the object of research, there is chosen city Tbilisi, the capital of Georgia, with a population of one and a half million and a difficult terrain. The main source of pollution in Tbilisi is currently vehicles and construction dust. The concentrations of dust and PM (Particulate Matter) were determined in the air of Tbilisi and in its vicinity. There are estimated their monthly maximum, minimum, and average concentrations. Processes of dust propagation in the atmosphere of the city and its surrounding territory are modelled using a 3D regional model of atmospheric processes and an admixture transfer-diffusion equation. There were taken figures of distribution of the polluted cloud and dust concentrations in different areas of the city at different heights and at different time intervals with the background stationary westward and eastward wind. It is accepted that the difficult terrain and mountain-bar circulation affect the deformation of the cloud and its spread, there are determined time periods when the dust concentration in the city is greater than MAC (Maximum Allowable Concentration, MAC=0.5 mg/m³).Keywords: air pollution, dust, numerical modeling, PM-particles
Procedia PDF Downloads 1313219 Microstructure Analysis of Biopolymer Mixture (Chia-Gelatin) by Laser Confocal Microscopy
Authors: Emmanuel Flores Huicochea, Guadalupe Borja Mendiola, Jacqueline Flores Lopez, Rodolfo Rendon Villalobos
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The usual procedure to investigate the properties of biodegradable films has been to prepare the film, measure the mechanical or transport properties and then decide whether the mixture has better properties than the individual components, instead of investigating whether the mixture has biopolymer-biopolymer interaction, then prepare the film and finally measure the properties of the film. The work investigates the presence of interaction biopolymer-biopolymer in a mixture of chia biopolymer and gelatin using Laser Confocal Microscopy (LCM). Previously, the chia biopolymer was obtained from chia seed. CML analysis of mixtures of chia biopolymer-gelatin without Na⁺ ions exhibited aggregates of different size, in the range of 100-400 μm, of defined color, for the two colors, but no mixing of color was observed. The increased of gelatin in the mixture decreases the size and number of aggregates. The tridimensional microstructure reveled that there are two layers of biopolymers, chia and gelatin well defined. The mixture chia biopolymer-gelatin with 10 mM Na⁺ and with a ratio 75:25 (chia-gelatin) showed lower aggregated size than others mixture with and without ions. This result could be explained because the chia biopolymer is a polyelectrolyte and the added sodium ions reduce the molecular rigidity by neutralizing the negative charges that the chia biopolymer possesses and therefore a better biopolymer-biopolymer interaction is allowed between the biopolymer of chia and gelatin.Keywords: biopolymer-biopolymer interaction, confocal laser microscopy, CLM, microstructure, mixture chia-gelatin
Procedia PDF Downloads 2013218 Validity and Reliability of Lifestyle Measurement of the LSAS among Recurrent Stroke Patients in Selected Hospital, Central Java, Indonesia
Authors: Meida Laely Ramdani, Earmporn Thongkrajai, Dedy Purwito
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Lifestyle is one of the most important factors affecting health. Measurement of lifestyle behaviors is necessary for the identification of causal associations between unhealthy lifestyle and health outcomes. There was many instruments have been measured for lifestyle, but not specific for stroke recurrence. This study aimed to develop a new questionnaire of Lifestyle Adjustment Scale (LSAS) among recurrent stroke patients in Indonesia and to measure the reliability and validity of LSAS. The instrument consist of 33 items was developed from the responses of 30 recurrent stroke patients with the maximum age 60 years. Data was collected during October to November 2015. The properties of the instrument were evaluated by validity assessment and reliability measures. The content validity was judged adequate by a panel of five experts, with the result of I-CVI was 0.97. The Cronbach’s alpha analysis was carried out to measure the reliability of LSAS. The result showed that Cronbach’s alpha coefficient was 0.819. LSAS were classified under the domains of dietary habit, smoking habit, physical activity, and stress management. The results of Cronbach’s alpha coefficient for each subscale were 0.60, 0.39, 0.67, 0.65 and 0.76 respectively. LSAS instrument was valid and reliable therefore can be used as research tool among recurrent stroke patients. The development of this questionnaire has been adapted to the socio-cultural context in Indonesia.Keywords: LSAS, recurrent stroke patients, lifestyle, Indonesia
Procedia PDF Downloads 2393217 Comparison of Sourcing Process in Supply Chain Operation References Model and Business Information Systems
Authors: Batuhan Kocaoglu
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Although using powerful systems like ERP (Enterprise Resource Planning), companies still cannot benchmark their processes and measure their process performance easily based on predefined SCOR (Supply Chain Operation References) terms. The purpose of this research is to identify common and corresponding processes to present a conceptual model to model and measure the purchasing process of an organization. The main steps for the research study are: Literature review related to 'procure to pay' process in ERP system; Literature review related to 'sourcing' process in SCOR model; To develop a conceptual model integrating 'sourcing' of SCOR model and 'procure to pay' of ERP model. In this study, we examined the similarities and differences between these two models. The proposed framework is based on the assumptions that are drawn from (1) the body of literature, (2) the authors’ experience by working in the field of enterprise and logistics information systems. The modeling framework provides a structured and systematic way to model and decompose necessary information from conceptual representation to process element specification. This conceptual model will help the organizations to make quality purchasing system measurement instruments and tools. And offered adaptation issues for ERP systems and SCOR model will provide a more benchmarkable and worldwide standard business process.Keywords: SCOR, ERP, procure to pay, sourcing, reference model
Procedia PDF Downloads 3563216 Level of Application of Integrated Talent Management According To IBM Institute for Business Value Case Study Palestinian Governmental Agencies in Gaza Strip
Authors: Iyad A. A. Abusahloub
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This research aimed to measure the level of perception and application of Integrated Talent Management according to IBM standards, by the upper and middle categories in Palestinian government institutions in Gaza, using a descriptive-analytical method. Using a questionnaire based on the standards of the IBM Institute for Business Value, the researcher added a second section to measure the perception of integrated talent management, the sample was 248 managers. The SPSS package was used for statistical analysis. The results showed that government institutions in Gaza apply Integrated Talent Management according to IBM standards at a medium degree did not exceed 59.8%, there is weakness in the perception of integrated talent management at the level of 53.6%, and there is a strong correlation between (Integrated Talent Management) and (the perception of the integrated talent management) amounted to 92.9%, and 88.9% of the change in the perception of the integrated talent management is by (motivate and develop, deploy and manage, connect and enable, and transform and sustain) talents, and 11.1% is by other factors. Conclusion: This study concluded that the integrated talent management model presented by IBM with its six dimensions is an effective model to reach your awareness and understanding of talent management, especially that it must rely on at least four basic dimensions out of the six dimensions: 1- Stimulating and developing talent. 2- Organizing and managing talent. 3- Connecting with talent and empowering it. 4- Succession and sustainability of talent. Therefore, this study recommends the adoption of the integrated talent management model provided by IBM to any organization across the world, regardless of its specialization or size, to reach talent sustainability.Keywords: HR, talent, talent management, IBM
Procedia PDF Downloads 783215 Effect of Carbon Nanotubes Functionalization with Nitrogen Groups on Pollutant Emissions in an Internal Combustion Engine
Authors: David Gamboa, Bernardo Herrera, Karen Cacua
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Nanomaterials have been explored as alternatives to reduce particulate matter from diesel engines, which is one of the most common pollutants of the air in urban centers. However, the use of nanomaterials as additives for diesel has to overcome the instability of the dispersions to be considered viable for commercial use. In this work, functionalization of carbon nanotubes with amide groups was performed to improve the stability of these nanomaterials in a mix of 90% petroleum diesel and 10% palm oil biodiesel (B10) in concentrations of 50 and 100 ppm. The resulting nano fuel was used as the fuel for a stationary internal combustion engine, where the particulate matter, NOx, and CO were measured. The results showed that the use of amide groups significantly enhances the time for the carbon nanotubes to remain suspended in the fuel, and at the same time, these nanomaterials helped to reduce the particulate matter and NOx emissions. However, the CO emissions with nano fuel were higher than those ones with the combustion of B10. These results suggest that carbon nanotubes have thermal and catalytic effects on the combustion of B10.Keywords: carbon nanotubes, diesel, internal combustion engine, particulate matter
Procedia PDF Downloads 1183214 Capturing the Stress States in Video Conferences by Photoplethysmographic Pulse Detection
Authors: Jarek Krajewski, David Daxberger
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We propose a stress detection method based on an RGB camera using heart rate detection, also known as Photoplethysmography Imaging (PPGI). This technique focuses on the measurement of the small changes in skin colour caused by blood perfusion. A stationary lab setting with simulated video conferences is chosen using constant light conditions and a sampling rate of 30 fps. The ground truth measurement of heart rate is conducted with a common PPG system. The proposed approach for pulse peak detection is based on a machine learning-based approach, applying brute force feature extraction for the prediction of heart rate pulses. The statistical analysis showed good agreement (correlation r = .79, p<0.05) between the reference heart rate system and the proposed method. Based on these findings, the proposed method could provide a reliable, low-cost, and contactless way of measuring HR parameters in daily-life environments.Keywords: heart rate, PPGI, machine learning, brute force feature extraction
Procedia PDF Downloads 1203213 Determining the Frequency of Pneumonia Emerging in COVID-19 Infection
Authors: Zoirov Amirdin Olimovich, Akbarov Elbek Elmurodovich
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Introduction: Pneumonia that occurs during COVID-19 infection is common among patients. This research was conducted to determine the frequency of symptoms occurring during pneumonia according to the purpose. Objective and Task: The goal of our research is to develop clinical concepts of pneumonia that occur during COVID-19 infection. Our main task is to analyze the results of blood tests and understand the progression of the disease. Research Materials and Methods: The research was conducted among patients admitted to the Tashkent Medical Academy multi-profile clinic in the department of infectious diseases undergoing stationary treatment with a diagnosis of COVID-19. The analyzed patients had an average age of 46, with a total of 48 patients, 23 of whom were female and 25 were male. Research Results: The research results showed the development of pneumonia within three days in 27 patients after COVID-19 infection. During the observation period, 24 patients (88.8%) recovered completely. The X-ray revealed no signs of pneumonia in those who fully recovered. The remaining three patients showed a persistent form of pneumonia. Conclusion: The conclusion of the research indicates that pneumonia during COVID-19 infection develops in many patients, and 88.8% of patients recover completely without any lingering symptoms.Keywords: COVID-19, pneumonia, the X-ray, blood, TTA
Procedia PDF Downloads 583212 Using the ISO 9705 Room Corner Test for Smoke Toxicity Quantification of Polyurethane
Authors: Gabrielle Peck, Ryan Hayes
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Polyurethane (PU) foam is typically sold as acoustic foam that is often used as sound insulation in settings such as night clubs and bars. As a construction product, PU is tested by being glued to the walls and ceiling of the ISO 9705 room corner test room. However, when heat is applied to PU foam, it melts and burns as a pool fire due to it being a thermoplastic. The current test layout is unable to accurately measure mass loss and doesn’t allow for the material to burn as a pool fire without seeping out of the test room floor. The lack of mass loss measurement means gas yields pertaining to smoke toxicity analysis can’t be calculated, which makes data comparisons from any other material or test method difficult. Additionally, the heat release measurements are not representative of the actual measurements taken as a lot of the material seeps through the floor (when a tray to catch the melted material is not used). This research aimed to modify the ISO 9705 test to provide the ability to measure mass loss to allow for better calculation of gas yields and understanding of decomposition. It also aimed to accurately measure smoke toxicity in both the doorway and duct and enable dilution factors to be calculated. Finally, the study aimed to examine if doubling the fuel loading would force under-ventilated flaming. The test layout was modified to be a combination of the SBI (single burning item) test set up inside oof the ISO 9705 test room. Polyurethane was tested in two different ways with the aim of altering the ventilation condition of the tests. Test one was conducted using 1 x SBI test rig aiming for well-ventilated flaming. Test two was conducted using 2 x SBI rigs (facing each other inside the test room) (doubling the fuel loading) aiming for under-ventilated flaming. The two different configurations used were successful in achieving both well-ventilated flaming and under-ventilated flaming, shown by the measured equivalence ratios (measured using a phi meter designed and created for these experiments). The findings show that doubling the fuel loading will successfully force under-ventilated flaming conditions to be achieved. This method can therefore be used when trying to replicate post-flashover conditions in future ISO 9705 room corner tests. The radiative heat generated by the two SBI rigs facing each other facilitated a much higher overall heat release resulting in a more severe fire. The method successfully allowed for accurate measurement of smoke toxicity produced from the PU foam in terms of simple gases such as oxygen depletion, CO and CO2. Overall, the proposed test modifications improve the ability to measure the smoke toxicity of materials in different fire conditions on a large-scale.Keywords: flammability, ISO9705, large-scale testing, polyurethane, smoke toxicity
Procedia PDF Downloads 713211 Lubricant-Impregnated Nanoporous Surfaces for Biofilm Prevention
Authors: Yuen Yee Li Sip, Lei Zhai
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Biofilms are formed by the attachment of microorganisms onto substrates via self-synthesized extracellular polymeric substances. They have been observed in the International Space Stations (ISS), in which biofilms can jeopardize the performance of key equipment and can pose health threats to the astronauts. This project aims at building conformal nanoporous surfaces that are infused with lubricant and decorated with antimicrobial nanoparticles while simultaneously evaluating their efficacy in preventing biofilm formation. Lubricant-impregnated surfaces (LIS) are fabricated by using a layer-by-layer assembly of silica nanoparticles to generate conformal nanoporous coatings on substrates and fill the films with fluorinated fluids. LIS has demonstrated excellent repellency to a broad range of liquids, preventing microbe adhesion (anti-biofouling). Silver or copper nanoparticles were deposited on the coatings prior to lubricant infusion in order to provide antimicrobial characteristics to the coating. Surface morphology and biofilm growth were characterized to understand how the coating morphology affects the LIS stability and anti-biofouling behaviors (stationary and in a flow).Keywords: biofilm, coatings, nanoporous, antifouling
Procedia PDF Downloads 92