Search results for: executive functions
2364 SVM-Based Modeling of Mass Transfer Potential of Multiple Plunging Jets
Authors: Surinder Deswal, Mahesh Pal
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The paper investigates the potential of support vector machines based regression approach to model the mass transfer capacity of multiple plunging jets, both vertical (θ = 90°) and inclined (θ = 60°). The data set used in this study consists of four input parameters with a total of eighty eight cases. For testing, tenfold cross validation was used. Correlation coefficient values of 0.971 and 0.981 (root mean square error values of 0.0025 and 0.0020) were achieved by using polynomial and radial basis kernel functions based support vector regression respectively. Results suggest an improved performance by radial basis function in comparison to polynomial kernel based support vector machines. The estimated overall mass transfer coefficient, by both the kernel functions, is in good agreement with actual experimental values (within a scatter of ±15 %); thereby suggesting the utility of support vector machines based regression approach.Keywords: mass transfer, multiple plunging jets, support vector machines, ecological sciences
Procedia PDF Downloads 4642363 Vibration Measurements of Single-Lap Cantilevered SPR Beams
Authors: Xiaocong He
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Self-pierce riveting (SPR) is a new high-speed mechanical fastening technique which is suitable for point joining dissimilar sheet materials, as well as coated and pre-painted sheet materials. Mechanical structures assembled by SPR are expected to possess a high damping capacity. In this study, experimental measurement techniques were proposed for the prediction of vibration behavior of single-lap cantilevered SPR beams. The dynamic test software and the data acquisition hardware were used in the experimental measurement of the dynamic response of the single-lap cantilevered SPR beams. Free and forced vibration behavior of the single-lap cantilevered SPR beams was measured using the LMS CADA-X experimental modal analysis software and the LMS-DIFA Scadas II data acquisition hardware. The frequency response functions of the SPR beams of different rivet number were compared. The main goal of the paper is to provide a basic measuring method for further research on vibration based non-destructive damage detection in single-lap cantilevered SPR beams.Keywords: self-piercing riveting, dynamic response, experimental measurement, frequency response functions
Procedia PDF Downloads 4292362 Dual-Rail Logic Unit in Double Pass Transistor Logic
Authors: Hamdi Belgacem, Fradi Aymen
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In this paper we present a low power, low cost differential logic unit (LU). The proposed LU receives dual-rail inputs and generates dual-rail outputs. The proposed circuit can be used in Arithmetic and Logic Units (ALU) of processor. It can be also dedicated for self-checking applications based on dual duplication code. Four logic functions as well as their inverses are implemented within a single Logic Unit. The hardware overhead for the implementation of the proposed LU is lower than the hardware overhead required for standard LU implemented with standard CMOS logic style. This new implementation is attractive as fewer transistors are required to implement important logic functions. The proposed differential logic unit can perform 8 Boolean logical operations by using only 16 transistors. Spice simulations using a 32 nm technology was utilized to evaluate the performance of the proposed circuit and to prove its acceptable electrical behaviour.Keywords: differential logic unit, double pass transistor logic, low power CMOS design, low cost CMOS design
Procedia PDF Downloads 4522361 Flocking Swarm of Robots Using Artificial Innate Immune System
Authors: Muneeb Ahmad, Ali Raza
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A computational method inspired by the immune system (IS) is presented, leveraging its shared characteristics of robustness, fault tolerance, scalability, and adaptability with swarm intelligence. This method aims to showcase flocking behaviors in a swarm of robots (SR). The innate part of the IS offers a variety of reactive and probabilistic cell functions alongside its self-regulation mechanism which have been translated to enable swarming behaviors. Although, the research is specially focused on flocking behaviors in a variety of simulated environments using e-puck robots in a physics-based simulator (CoppeliaSim); the artificial innate immune system (AIIS) can exhibit other swarm behaviors as well. The effectiveness of the immuno-inspired approach has been established with extensive experimentations, for scalability and adaptability, using standard swarm benchmarks as well as the immunological regulatory functions (i.e., Dendritic Cells’ Maturity and Inflammation). The AIIS-based approach has proved to be a scalable and adaptive solution for emulating the flocking behavior of SR.Keywords: artificial innate immune system, flocking swarm, immune system, swarm intelligence
Procedia PDF Downloads 1042360 A Study of Evolutional Control Systems
Authors: Ti-Jun Xiao, Zhe Xu
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Controllability is one of the fundamental issues in control systems. In this paper, we study the controllability of second order evolutional control systems in Hilbert spaces with memory and boundary controls, which model dynamic behaviors of some viscoelastic materials. Transferring the control problem into a moment problem and showing the Riesz property of a family of functions related to Cauchy problems for some integrodifferential equations, we obtain a general boundary controllability theorem for these second order evolutional control systems. This controllability theorem is applicable to various concrete 1D viscoelastic systems and recovers some previous related results. It is worth noting that Riesz sequences can be used for numerical computations of the control functions and the identification of new Riesz sequence is of independent interest for the basis-function theory. Moreover, using the Riesz sequences, we obtain the existence and uniqueness of (weak) solutions to these second order evolutional control systems in Hilbert spaces. Finally, we derive the exact boundary controllability of a viscoelastic beam equation, as an application of our abstract theorem.Keywords: evolutional control system, controllability, boundary control, existence and uniqueness
Procedia PDF Downloads 2222359 Challenges to Change and Innovation in Educational System
Authors: Felicia Kikelomo Oluwalola
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The study was designed to identify the challenges to change and innovation in educational system in Nigeria. Educational institutions, like all other organizations, require constant monitoring, to identify areas for potential improvement. However, educational reforms are often not well-implemented. This results in massive wastage of finances, human resources, and lost potential. Educational institutions are organised on many levels, from the individual classroom under the management of a single teacher, to groups of classrooms supervised by a Head Teacher or Executive Teacher, to a whole-school structure, under the guidance of the principal. Therefore, there is need for changes and innovation in our educational system since we are in the era of computer age. In doing so, this paper examined the psychology of change, concept of change and innovation with suggested view points. Educational administrators and individuals should be ready to have the challenge of monitoring changes in technologies. Educational planners/policy makers should be encouraged to involve in change process.Keywords: challenges, change, education, innovation
Procedia PDF Downloads 6122358 Finding the Elastic Field in an Arbitrary Anisotropic Media by Implementing Accurate Generalized Gaussian Quadrature Solution
Authors: Hossein Kabir, Amir Hossein Hassanpour Mati-Kolaie
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In the current study, the elastic field in an anisotropic elastic media is determined by implementing a general semi-analytical method. In this specific methodology, the displacement field is computed as a sum of finite functions with unknown coefficients. These aforementioned functions satisfy exactly both the homogeneous and inhomogeneous boundary conditions in the proposed media. It is worth mentioning that the unknown coefficients are determined by implementing the principle of minimum potential energy. The numerical integration is implemented by employing the Generalized Gaussian Quadrature solution. Furthermore, with the aid of the calculated unknown coefficients, the displacement field, as well as the other parameters of the elastic field, are obtainable as well. Finally, the comparison of the previous analytical method with the current semi-analytical method proposes the efficacy of the present methodology.Keywords: anisotropic elastic media, semi-analytical method, elastic field, generalized gaussian quadrature solution
Procedia PDF Downloads 3212357 Continuous Functions Modeling with Artificial Neural Network: An Improvement Technique to Feed the Input-Output Mapping
Authors: A. Belayadi, A. Mougari, L. Ait-Gougam, F. Mekideche-Chafa
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The artificial neural network is one of the interesting techniques that have been advantageously used to deal with modeling problems. In this study, the computing with artificial neural network (CANN) is proposed. The model is applied to modulate the information processing of one-dimensional task. We aim to integrate a new method which is based on a new coding approach of generating the input-output mapping. The latter is based on increasing the neuron unit in the last layer. Accordingly, to show the efficiency of the approach under study, a comparison is made between the proposed method of generating the input-output set and the conventional method. The results illustrated that the increasing of the neuron units, in the last layer, allows to find the optimal network’s parameters that fit with the mapping data. Moreover, it permits to decrease the training time, during the computation process, which avoids the use of computers with high memory usage.Keywords: neural network computing, continuous functions generating the input-output mapping, decreasing the training time, machines with big memories
Procedia PDF Downloads 2832356 Cognitive Performance Post Stroke Is Affected by the Timing of Evaluation
Authors: Ayelet Hersch, Corrine Serfaty, Sigal Portnoy
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Stroke survivors commonly report persistent fatigue and sleep disruptions during rehabilitation and post-recovery. While limited research has explored the impact of stroke on a patient's chronotype, there is a gap in understanding the differences in cognitive performance based on treatment timing. Study objectives: (a) To characterize the sleep chronotype in sub-acute post-stroke individuals. (b) Explore cognitive task performance differences during preferred and non-preferred hours. (c) Examine the relationships between sleep quality and cognitive performance. For this intra-subject study, twenty participants (mean age 60.2±8.6) post-first stroke (6-12 weeks post stroke) underwent assessments at preferred and non-preferred chronotypic times. The assessment included demographic surveys, the Munich Chronotype Questionnaire, Montreal Cognitive Assessment (MoCA), Rivermead Behavioral Memory Test (RBMT), a fatigue questionnaire, and 4-5 days of actigraphy (wrist-worn wGT3X-BT, ActiGraph) to record sleep characteristics. Four sleep quality indices were extracted from actigraphy wristwatch recordings: The average of total sleep time per day (minutes), the average number of awakenings during the sleep period per day, the efficiency of sleep (total hours of sleep per day divided by hours spent in bed per day, averaged across the days and presented as percentage), and the Wake after Sleep Onset (WASO) index, indicating the average number of minutes elapsed from the onset of sleep to the first awakening. Stroke survivors exhibited an earlier sleep chronotype post-injury compared to pre-injury. Enhanced attention, as indicated by higher RBMT scores, occurred during preferred hours. Specifically, 30% of the study participants demonstrated an elevation in their final scores during their preferred hours, transitioning from the category of "mild memory impairment" to "normal memory." However, no significant differences emerged in executive functions, attention tasks, and MoCA scores between preferred and non-preferred hours. The Wake After Sleep Onset (WASO) index correlated with MoCA/RBMT scores during preferred hours (r=0.53/0.51, p=0.021/0.027, respectively). The number of awakenings correlated with MoCA letter task performance during non-preferred hours (r=0.45, p=0.044). Enhanced attention during preferred hours suggests a potential relationship between chronotype and cognitive performance, highlighting the importance of personalized rehabilitation strategies in stroke care. Further exploration of these relationships could contribute to optimizing the timing of cognitive interventions for stroke survivors.Keywords: sleep chronotype, chronobiology, circadian rhythm, rehabilitation timing
Procedia PDF Downloads 652355 Secure Cryptographic Operations on SIM Card for Mobile Financial Services
Authors: Kerem Ok, Serafettin Senturk, Serdar Aktas, Cem Cevikbas
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Mobile technology is very popular nowadays and it provides a digital world where users can experience many value-added services. Service Providers are also eager to offer diverse value-added services to users such as digital identity, mobile financial services and so on. In this context, the security of data storage in smartphones and the security of communication between the smartphone and service provider are critical for the success of these services. In order to provide the required security functions, the SIM card is one acceptable alternative. Since SIM cards include a Secure Element, they are able to store sensitive data, create cryptographically secure keys, encrypt and decrypt data. In this paper, we design and implement a SIM and a smartphone framework that uses a SIM card for secure key generation, key storage, data encryption, data decryption and digital signing for mobile financial services. Our frameworks show that the SIM card can be used as a controlled Secure Element to provide required security functions for popular e-services such as mobile financial services.Keywords: SIM card, mobile financial services, cryptography, secure data storage
Procedia PDF Downloads 3122354 Artificial Intelligent Methodology for Liquid Propellant Engine Design Optimization
Authors: Hassan Naseh, Javad Roozgard
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This paper represents the methodology based on Artificial Intelligent (AI) applied to Liquid Propellant Engine (LPE) optimization. The AI methodology utilized from Adaptive neural Fuzzy Inference System (ANFIS). In this methodology, the optimum objective function means to achieve maximum performance (specific impulse). The independent design variables in ANFIS modeling are combustion chamber pressure and temperature and oxidizer to fuel ratio and output of this modeling are specific impulse that can be applied with other objective functions in LPE design optimization. To this end, the LPE’s parameter has been modeled in ANFIS methodology based on generating fuzzy inference system structure by using grid partitioning, subtractive clustering and Fuzzy C-Means (FCM) clustering for both inferences (Mamdani and Sugeno) and various types of membership functions. The final comparing optimization results shown accuracy and processing run time of the Gaussian ANFIS Methodology between all methods.Keywords: ANFIS methodology, artificial intelligent, liquid propellant engine, optimization
Procedia PDF Downloads 5892353 Dynamic Reroute Modeling for Emergency Evacuation: Case Study of Brunswick City, Germany
Authors: Yun-Pang Flötteröd, Jakob Erdmann
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The human behaviors during evacuations are quite complex. One of the critical behaviors which affect the efficiency of evacuation is route choice. Therefore, the respective simulation modeling work needs to function properly. In this paper, Simulation of Urban Mobility’s (SUMO) current dynamic route modeling during evacuation, i.e. the rerouting functions, is examined with a real case study. The result consistency of the simulation and the reality is checked as well. Four influence factors (1) time to get information, (2) probability to cancel a trip, (3) probability to use navigation equipment, and (4) rerouting and information updating period are considered to analyze possible traffic impacts during the evacuation and to examine the rerouting functions in SUMO. Furthermore, some behavioral characters of the case study are analyzed with use of the corresponding detector data and applied in the simulation. The experiment results show that the dynamic route modeling in SUMO can deal with the proposed scenarios properly. Some issues and function needs related to route choice are discussed and further improvements are suggested.Keywords: evacuation, microscopic traffic simulation, rerouting, SUMO
Procedia PDF Downloads 1942352 Pragmatic Discoursal Study of Hedging Constructions in English Language
Authors: Mohammed Hussein Ahmed, Bahar Mohammed Kareem
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This study is concerned with the pragmatic discoursal study of hedging constructions in English language. Hedging is a mitigated word used to lessen the impact of the utterance uttered by the speakers. Hedging could be either adverbs, adjectives, verbs and sometimes it may consist of clauses. It aims at finding out the extent to which speakers and participants of the discourse use hedging constructions during their conversations. The study also aims at finding out whether or not there are any significant differences in the types and functions of the frequency of hedging constructions employed by male and female. It is hypothesized that hedging constructions are frequent in English discourse more than any other languages due to its formality and that the frequency of the types and functions are influenced by the gender of the participants. To achieve the aims of the study, two types of procedures have been followed: theoretical and practical. The theoretical procedure consists of presenting a theoretical background of hedging topic which includes its definitions, etymology and theories. The practical procedure consists of selecting a sample of texts and analyzing them according to an adopted model. A number of conclusions will be drawn based on the findings of the study.Keywords: hedging, pragmatics, politeness, theoretical
Procedia PDF Downloads 5872351 The Impact of Neuroscience Knowledge on the Field of Education
Authors: Paula Andrea Segura Delgado, Martha Helena Ramírez-Bahena
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Research on how the brain learns has a transcendental application in the educational context. It is crucial for teacher training to understand the nature of brain changes and their direct influence on learning processes. This communication is based on a literature review focused on neuroscience, neuroeducation, and the impact of digital technology on the human brain. Information was gathered from both English and Spanish language sources, using online journals, books and reports. The general objective was to analyze the role of neuroscience knowledge in enriching our understanding of the learning process. In fact, the authors have focused on the impact of digital technology on the human brain as well as its influence in the field of education..Neuroscience knowledge can contribute significantly to improving the training of educators and therefore educational practices. Education as an instrument of change and school as an agent of socialization, it is necessary to understand what it aims to transform: the human brain. Understanding the functioning of the human brain has important repercussions on education: this elucidates cognitive skills, psychological processes and elements that influence the learning process (memory, executive functions, emotions and the circadian cycle); helps identify psychological and neurological deficits that can impede learning processes (dyslexia, autism, hyperactivity); It allows creating environments that promote brain development and contribute to the advancement of brain capabilities in alignment with the stages of neurobiological development. The digital age presents diverse opportunities to every social environment. The frequent use of digital technology (DT) has had a significant and abrupt impact on both the cognitive abilities and physico-chemical properties of the brain, significantly influencing educational processes. Hence, educational community, with the insights from advances in neuroscience, aspire to identify the positive and negative effects of digital technology on the human brain. This knowledge helps ensure the alignment of teacher training and practices with these findings. The knowledge of neuroscience enables teachers to develop teaching methods that are aligned with the way the brain works. For example, neuroscience research has shown that digital technology is having a significant impact on the human brain (addition, anxiety, high levels of dopamine, circadian cycle disorder, decrease in attention, memory, concentration, problems with their social relationships). Therefore, it is important to understand the nature of these changes, their impact on the learning process, and how educators should effectively adapt their approaches based on these brain's changes.Keywords: digital technology, learn process, neuroscience knowledge, neuroeducation, training proffesors
Procedia PDF Downloads 622350 Investigating a Deterrence Function for Work Trips for Perth Metropolitan Area
Authors: Ali Raouli, Amin Chegenizadeh, Hamid Nikraz
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The Perth metropolitan area and its surrounding regions have been expanding rapidly in recent decades and it is expected that this growth will continue in the years to come. With this rapid growth and the resulting increase in population, consideration should be given to strategic planning and modelling for the future expansion of Perth. The accurate estimation of projected traffic volumes has always been a major concern for the transport modelers and planners. Development of a reliable strategic transport model depends significantly on the inputs data into the model and the calibrated parameters of the model to reflect the existing situation. Trip distribution is the second step in four-step modelling (FSM) which is complex due to its behavioral nature. Gravity model is the most common method for trip distribution. The spatial separation between the Origin and Destination (OD) zones will be reflected in gravity model by applying deterrence functions which provide an opportunity to include people’s behavior in choosing their destinations based on distance, time and cost of their journeys. Deterrence functions play an important role for distribution of the trips within a study area and would simulate the trip distances and therefore should be calibrated for any particular strategic transport model to correctly reflect the trip behavior within the modelling area. This paper aims to review the most common deterrence functions and propose a calibrated deterrence function for work trips within the Perth Metropolitan Area based on the information obtained from the latest available Household data and Perth and Region Travel Survey (PARTS) data. As part of this study, a four-step transport model using EMME software has been developed for Perth Metropolitan Area to assist with the analysis and findings.Keywords: deterrence function, four-step modelling, origin destination, transport model
Procedia PDF Downloads 1682349 Effects of Oral L-Carnitine on Liver Functions after Trans arterial Chemoembolization in Hepatocellular Carcinoma Patients
Authors: Ali Kassem, Aly Taha, Abeer Hassan, Kazuhide Higuchi
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Introduction: Trans arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) is usually followed by hepatic dysfunction that limits its efficacy. L-carnitine is recently studied as hepatoprotective agent. Our aim is to evaluate the L-carnitine effects against the deterioration of liver functions after TACE. Method: 53 patients with intermediate stage HCC were assigned into two groups; L-carnitine group (26 patients) who received L-carnitine 300 mg tablet twice daily from 2 weeks before to 12 weeks after TACE and control group (27 patients) without L-carnitine therapy. 28 of studied patients received branched chain amino acids granules. Results: There were significant differences between L-carnitine Vs. control group in mean serum albumin change from baseline to 1 week and 4 weeks after TACE (p < 0.05). L-Carnitine maintained Child-Pugh score at 1 week after TACE and exhibited improvement at 4 weeks after TACE (p < 0.01 Vs 1 week after TACE). Control group has significant Child-Pugh score deterioration from baseline to 1 week after TACE (p < 0.05) and 12 weeks after TACE (p < 0.05). There were significant differences between L-carnitine and control groups in mean Child-Pugh score change from baseline to 4 weeks (p < 0.05) and 12 weeks after TACE (p < 0.05). L-carnitine displayed improvement in (PT) from baseline to 1 week, 4 w (p < 0.05) and 12 weeks after TACE. PT in control group declined less than baseline along all follow up intervals. Total bilirubin in L-carnitine group decreased at 1 week post TACE while in control group, it significantly increased at 1 week (p = 0.01). ALT and C-reactive protein elevation were suppressed at 1 week after TACE in Lcarnitine group. The hepatoprotective effects of L-carnitine were enhanced by concomitant use of branched chain amino acids. Conclusion: L-carnitine and BCAA combination therapy offer a novel supportive strategy after TACE in HCC patients.Keywords: hepatocellular carcinoma, L-carnitine, liver functions , trans-arterial embolization
Procedia PDF Downloads 1552348 Modified Weibull Approach for Bridge Deterioration Modelling
Authors: Niroshan K. Walgama Wellalage, Tieling Zhang, Richard Dwight
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State-based Markov deterioration models (SMDM) sometimes fail to find accurate transition probability matrix (TPM) values, and hence lead to invalid future condition prediction or incorrect average deterioration rates mainly due to drawbacks of existing nonlinear optimization-based algorithms and/or subjective function types used for regression analysis. Furthermore, a set of separate functions for each condition state with age cannot be directly derived by using Markov model for a given bridge element group, which however is of interest to industrial partners. This paper presents a new approach for generating Homogeneous SMDM model output, namely, the Modified Weibull approach, which consists of a set of appropriate functions to describe the percentage condition prediction of bridge elements in each state. These functions are combined with Bayesian approach and Metropolis Hasting Algorithm (MHA) based Markov Chain Monte Carlo (MCMC) simulation technique for quantifying the uncertainty in model parameter estimates. In this study, factors contributing to rail bridge deterioration were identified. The inspection data for 1,000 Australian railway bridges over 15 years were reviewed and filtered accordingly based on the real operational experience. Network level deterioration model for a typical bridge element group was developed using the proposed Modified Weibull approach. The condition state predictions obtained from this method were validated using statistical hypothesis tests with a test data set. Results show that the proposed model is able to not only predict the conditions in network-level accurately but also capture the model uncertainties with given confidence interval.Keywords: bridge deterioration modelling, modified weibull approach, MCMC, metropolis-hasting algorithm, bayesian approach, Markov deterioration models
Procedia PDF Downloads 7272347 Ethical Leadership and Employee Creative Behaviour: A Case Study of a State-Owned Enterprise in South Africa
Authors: Krishna Kistan Govender, Alex Masianoga
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The aim of this explanatory study was to critically understand how ethical leadership impacts employee creative behaviour, as well as the creative behaviour dimensions, in a South African transport and logistics SOE. A quantitative study was conducted using a pre-developed questionnaire, and data for 160 middle and executive managers was analysed through structural equation modelling and multiple regression techniques conducted with the Smart PLS statistical software. All five hypothesized relationships were supported, and it was confirmed that ethical leadership has a significant positive influence on employee creative behaviour, as well as on each of the creative behaviour dimensions, namely: idea exploration, idea generation, idea championing, and idea implementation.Keywords: ethical leaders, employee creative behaviour, state-owned enterprises, South Africa
Procedia PDF Downloads 1262346 Modelling of Heat Generation in a 18650 Lithium-Ion Battery Cell under Varying Discharge Rates
Authors: Foo Shen Hwang, Thomas Confrey, Stephen Scully, Barry Flannery
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Thermal characterization plays an important role in battery pack design. Lithium-ion batteries have to be maintained between 15-35 °C to operate optimally. Heat is generated (Q) internally within the batteries during both the charging and discharging phases. This can be quantified using several standard methods. The most common method of calculating the batteries heat generation is through the addition of both the joule heating effects and the entropic changes across the battery. In addition, such values can be derived by identifying the open-circuit voltage (OCV), nominal voltage (V), operating current (I), battery temperature (T) and the rate of change of the open-circuit voltage in relation to temperature (dOCV/dT). This paper focuses on experimental characterization and comparative modelling of the heat generation rate (Q) across several current discharge rates (0.5C, 1C, and 1.5C) of a 18650 cell. The analysis is conducted utilizing several non-linear mathematical functions methods, including polynomial, exponential, and power models. Parameter fitting is carried out over the respective function orders; polynomial (n = 3~7), exponential (n = 2) and power function. The generated parameter fitting functions are then used as heat source functions in a 3-D computational fluid dynamics (CFD) solver under natural convection conditions. Generated temperature profiles are analyzed for errors based on experimental discharge tests, conducted at standard room temperature (25°C). Initial experimental results display low deviation between both experimental and CFD temperature plots. As such, the heat generation function formulated could be easier utilized for larger battery applications than other methods available.Keywords: computational fluid dynamics, curve fitting, lithium-ion battery, voltage drop
Procedia PDF Downloads 952345 A Deterministic Approach for Solving the Hull and White Interest Rate Model with Jump Process
Authors: Hong-Ming Chen
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This work considers the resolution of the Hull and White interest rate model with the jump process. A deterministic process is adopted to model the random behavior of interest rate variation as deterministic perturbations, which is depending on the time t. The Brownian motion and jumps uncertainty are denoted as the integral functions piecewise constant function w(t) and point function θ(t). It shows that the interest rate function and the yield function of the Hull and White interest rate model with jump process can be obtained by solving a nonlinear semi-infinite programming problem. A relaxed cutting plane algorithm is then proposed for solving the resulting optimization problem. The method is calibrated for the U.S. treasury securities at 3-month data and is used to analyze several effects on interest rate prices, including interest rate variability, and the negative correlation between stock returns and interest rates. The numerical results illustrate that our approach essentially generates the yield functions with minimal fitting errors and small oscillation.Keywords: optimization, interest rate model, jump process, deterministic
Procedia PDF Downloads 1612344 Loss Function Optimization for CNN-Based Fingerprint Anti-Spoofing
Authors: Yehjune Heo
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As biometric systems become widely deployed, the security of identification systems can be easily attacked by various spoof materials. This paper contributes to finding a reliable and practical anti-spoofing method using Convolutional Neural Networks (CNNs) based on the types of loss functions and optimizers. The types of CNNs used in this paper include AlexNet, VGGNet, and ResNet. By using various loss functions including Cross-Entropy, Center Loss, Cosine Proximity, and Hinge Loss, and various loss optimizers which include Adam, SGD, RMSProp, Adadelta, Adagrad, and Nadam, we obtained significant performance changes. We realize that choosing the correct loss function for each model is crucial since different loss functions lead to different errors on the same evaluation. By using a subset of the Livdet 2017 database, we validate our approach to compare the generalization power. It is important to note that we use a subset of LiveDet and the database is the same across all training and testing for each model. This way, we can compare the performance, in terms of generalization, for the unseen data across all different models. The best CNN (AlexNet) with the appropriate loss function and optimizers result in more than 3% of performance gain over the other CNN models with the default loss function and optimizer. In addition to the highest generalization performance, this paper also contains the models with high accuracy associated with parameters and mean average error rates to find the model that consumes the least memory and computation time for training and testing. Although AlexNet has less complexity over other CNN models, it is proven to be very efficient. For practical anti-spoofing systems, the deployed version should use a small amount of memory and should run very fast with high anti-spoofing performance. For our deployed version on smartphones, additional processing steps, such as quantization and pruning algorithms, have been applied in our final model.Keywords: anti-spoofing, CNN, fingerprint recognition, loss function, optimizer
Procedia PDF Downloads 1362343 Key Frame Based Video Summarization via Dependency Optimization
Authors: Janya Sainui
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As a rapid growth of digital videos and data communications, video summarization that provides a shorter version of the video for fast video browsing and retrieval is necessary. Key frame extraction is one of the mechanisms to generate video summary. In general, the extracted key frames should both represent the entire video content and contain minimum redundancy. However, most of the existing approaches heuristically select key frames; hence, the selected key frames may not be the most different frames and/or not cover the entire content of a video. In this paper, we propose a method of video summarization which provides the reasonable objective functions for selecting key frames. In particular, we apply a statistical dependency measure called quadratic mutual informaion as our objective functions for maximizing the coverage of the entire video content as well as minimizing the redundancy among selected key frames. The proposed key frame extraction algorithm finds key frames as an optimization problem. Through experiments, we demonstrate the success of the proposed video summarization approach that produces video summary with better coverage of the entire video content while less redundancy among key frames comparing to the state-of-the-art approaches.Keywords: video summarization, key frame extraction, dependency measure, quadratic mutual information
Procedia PDF Downloads 2662342 Path Integrals and Effective Field Theory of Large Scale Structure
Authors: Revant Nayar
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In this work, we recast the equations describing large scale structure, and by extension all nonlinear fluids, in the path integral formalism. We first calculate the well known two and three point functions using Schwinger Keldysh formalism used commonly to perturbatively solve path integrals in non- equilibrium systems. Then we include EFT corrections due to pressure, viscosity, and noise as effects on the time-dependent propagator. We are able to express results for arbitrary two and three point correlation functions in LSS in terms of differential operators acting on a triple K master intergral. We also, for the first time, get analytical results for more general initial conditions deviating from the usual power law P∝kⁿ by introducing a mass scale in the initial conditions. This robust field theoretic formalism empowers us with tools from strongly coupled QFT to study the strongly non-linear regime of LSS and turbulent fluid dynamics such as OPE and holographic duals. These could be used to capture fully the strongly non-linear dynamics of fluids and move towards solving the open problem of classical turbulence.Keywords: quantum field theory, cosmology, effective field theory, renormallisation
Procedia PDF Downloads 1352341 Self-denigration in Doctoral Defense Sessions: Scale Development and Validation
Authors: Alireza Jalilifar, Nadia Mayahi
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The dissertation defense as a complicated conflict-prone context entails the adoption of elegant interactional strategies, one of which is self-denigration. This study aimed to develop and validate a self-denigration model that fits the context of doctoral defense sessions in applied linguistics. Two focus group discussions provided the basis for developing this conceptual model, which assumed 10 functions for self-denigration, namely good manners, modesty, affability, altruism, assertiveness, diffidence, coercive self-deprecation, evasion, diplomacy, and flamboyance. These functions were used to design a 40-item questionnaire on the attitudes of applied linguists concerning self-denigration in defense sessions. The confirmatory factor analysis of the questionnaire indicated the predictive ability of the measurement model. The findings of this study suggest that self-denigration in doctoral defense sessions is the social representation of the participants’ values, ideas and practices adopted as a negotiation strategy and a conflict management policy for the purpose of establishing harmony and maintaining resilience. This study has implications for doctoral students and academics and illuminates further research on self-denigration in other contexts.Keywords: academic discourse, politeness, self-denigration, grounded theory, dissertation defense
Procedia PDF Downloads 1372340 A Practical and Efficient Evaluation Function for 3D Model Based Vehicle Matching
Authors: Yuan Zheng
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3D model-based vehicle matching provides a new way for vehicle recognition, localization and tracking. Its key is to construct an evaluation function, also called fitness function, to measure the degree of vehicle matching. The existing fitness functions often poorly perform when the clutter and occlusion exist in traffic scenarios. In this paper, we present a practical and efficient fitness function. Unlike the existing evaluation functions, the proposed fitness function is to study the vehicle matching problem from both local and global perspectives, which exploits the pixel gradient information as well as the silhouette information. In view of the discrepancy between 3D vehicle model and real vehicle, a weighting strategy is introduced to differently treat the fitting of the model’s wireframes. Additionally, a normalization operation for the model’s projection is performed to improve the accuracy of the matching. Experimental results on real traffic videos reveal that the proposed fitness function is efficient and robust to the cluttered background and partial occlusion.Keywords: 3D-2D matching, fitness function, 3D vehicle model, local image gradient, silhouette information
Procedia PDF Downloads 3992339 An Interpolation Tool for Data Transfer in Two-Dimensional Ice Accretion Problems
Authors: Marta Cordero-Gracia, Mariola Gomez, Olivier Blesbois, Marina Carrion
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One of the difficulties in icing simulations is for extended periods of exposure, when very large ice shapes are created. As well as being large, they can have complex shapes, such as a double horn. For icing simulations, these configurations are currently computed in several steps. The icing step is stopped when the ice shapes become too large, at which point a new mesh has to be created to allow for further CFD and ice growth simulations to be performed. This can be very costly, and is a limiting factor in the simulations that can be performed. A way to avoid the costly human intervention in the re-meshing step of multistep icing computation is to use mesh deformation instead of re-meshing. The aim of the present work is to apply an interpolation method based on Radial Basis Functions (RBF) to transfer deformations from surface mesh to volume mesh. This deformation tool has been developed specifically for icing problems. It is able to deal with localized, sharp and large deformations, unlike the tools traditionally used for more smooth wing deformations. This tool will be presented along with validation on typical two-dimensional icing shapes.Keywords: ice accretion, interpolation, mesh deformation, radial basis functions
Procedia PDF Downloads 3132338 Development of a Fuzzy Logic Based Model for Monitoring Child Pornography
Authors: Mariam Ismail, Kazeem Rufai, Jeremiah Balogun
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A study was conducted to apply fuzzy logic to the development of a monitoring model for child pornography based on associated risk factors, which can be used by forensic experts or integrated into forensic systems for the early detection of child pornographic activities. A number of methods were adopted in the study, which includes an extensive review of related works was done in order to identify the factors that are associated with child pornography following which they were validated by an expert sex psychologist and guidance counselor, and relevant data was collected. Fuzzy membership functions were used to fuzzify the associated variables identified alongside the risk of the occurrence of child pornography based on the inference rules that were provided by the experts consulted, and the fuzzy logic expert system was simulated using the Fuzzy Logic Toolbox available in the MATLAB Software Release 2016. The results of the study showed that there were 4 categories of risk factors required for assessing the risk of a suspect committing child pornography offenses. The results of the study showed that 2 and 3 triangular membership functions were used to formulate the risk factors based on the 2 and 3 number of labels assigned, respectively. The results of the study showed that 5 fuzzy logic models were formulated such that the first 4 was used to assess the impact of each category on child pornography while the last one takes the 4 outputs from the 4 fuzzy logic models as inputs required for assessing the risk of child pornography. The following conclusion was made; there were factors that were related to personal traits, social traits, history of child pornography crimes, and self-regulatory deficiency traits by the suspects required for the assessment of the risk of child pornography crimes committed by a suspect. Using the values of the identified risk factors selected for this study, the risk of child pornography can be easily assessed from their values in order to determine the likelihood of a suspect perpetuating the crime.Keywords: fuzzy, membership functions, pornography, risk factors
Procedia PDF Downloads 1302337 Handwriting Velocity Modeling by Artificial Neural Networks
Authors: Mohamed Aymen Slim, Afef Abdelkrim, Mohamed Benrejeb
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The handwriting is a physical demonstration of a complex cognitive process learnt by man since his childhood. People with disabilities or suffering from various neurological diseases are facing so many difficulties resulting from problems located at the muscle stimuli (EMG) or signals from the brain (EEG) and which arise at the stage of writing. The handwriting velocity of the same writer or different writers varies according to different criteria: age, attitude, mood, writing surface, etc. Therefore, it is interesting to reconstruct an experimental basis records taking, as primary reference, the writing speed for different writers which would allow studying the global system during handwriting process. This paper deals with a new approach of the handwriting system modeling based on the velocity criterion through the concepts of artificial neural networks, precisely the Radial Basis Functions (RBF) neural networks. The obtained simulation results show a satisfactory agreement between responses of the developed neural model and the experimental data for various letters and forms then the efficiency of the proposed approaches.Keywords: Electro Myo Graphic (EMG) signals, experimental approach, handwriting process, Radial Basis Functions (RBF) neural networks, velocity modeling
Procedia PDF Downloads 4402336 Elastohydrodynamic Lubrication Study Using Discontinuous Finite Volume Method
Authors: Prawal Sinha, Peeyush Singh, Pravir Dutt
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Problems in elastohydrodynamic lubrication have attracted a lot of attention in the last few decades. Solving a two-dimensional problem has always been a big challenge. In this paper, a new discontinuous finite volume method (DVM) for two-dimensional point contact Elastohydrodynamic Lubrication (EHL) problem has been developed and analyzed. A complete algorithm has been presented for solving such a problem. The method presented is robust and easily parallelized in MPI architecture. GMRES technique is implemented to solve the matrix obtained after the formulation. A new approach is followed in which discontinuous piecewise polynomials are used for the trail functions. It is natural to assume that the advantages of using discontinuous functions in finite element methods should also apply to finite volume methods. The nature of the discontinuity of the trail function is such that the elements in the corresponding dual partition have the smallest support as compared with the Classical finite volume methods. Film thickness calculation is done using singular quadrature approach. Results obtained have been presented graphically and discussed. This method is well suited for solving EHL point contact problem and can probably be used as commercial software.Keywords: elastohydrodynamic, lubrication, discontinuous finite volume method, GMRES technique
Procedia PDF Downloads 2572335 Argument Representation in Non-Spatial Motion Bahasa Melayu Based Conceptual Structure Theory
Authors: Nurul Jamilah Binti Rosly
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The typology of motion must be understood as a change from one location to another. But from a conceptual point of view, motion can also occur in non-spatial contexts associated with human and social factors. Therefore, from the conceptual point of view, the concept of non-spatial motion involves the movement of time, ownership, identity, state, and existence. Accordingly, this study will focus on the lexical as shared, accept, be, store, and exist as the study material. The data in this study were extracted from the Database of Languages and Literature Corpus Database, Malaysia, which was analyzed using semantics and syntax concepts using Conceptual Structure Theory - Ray Jackendoff (2002). Semantic representations are represented in the form of conceptual structures in argument functions that include functions [events], [situations], [objects], [paths] and [places]. The findings show that the mapping of these arguments comprises three main stages, namely mapping the argument structure, mapping the tree, and mapping the role of thematic items. Accordingly, this study will show the representation of non- spatial Malay language areas.Keywords: arguments, concepts, constituencies, events, situations, thematics
Procedia PDF Downloads 129