Search results for: boundary fitted nested model
15905 Numerical Simulation of Ultraviolet Disinfection in a Water Reactor
Authors: H. Shokouhmand, H. Sobhani, B. Sajadi, M. Degheh
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In recent years, experimental and numerical investigation of water UV reactors has increased significantly. The main drawback of experimental methods is confined and expensive survey of UV reactors features. In this study, a CFD model utilizing the eulerian-lagrangian framework is applied to analysis the disinfection performance of a closed conduit reactor which contains four UV lamps perpendicular to the flow. A discrete ordinates (DO) model was employed to evaluate the UV irradiance field. To investigate the importance of each of lamps on the inactivation performance, in addition to the reference model (with 4 bright lamps), several models with one or two bright lamps in various arrangements were considered. All results were reported in three inactivation kinetics. The results showed that the log inactivation of the two central bright lamps model was between 88-99 percent, close to the reference model results. Also, whatever the lamps are closer to the main flow region, they have more effect on microbial inactivation. The effect of some operational parameters such as water flow rate, inlet water temperature, and lamps power were also studied.Keywords: Eulerian-Lagrangian framework, inactivation kinetics, log inactivation, water UV reactor
Procedia PDF Downloads 25115904 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 16115903 E-Commerce Implementation to Support Customize Clothes for Obese People
Authors: Hamza Al-Hazmi, Tabrej Khan
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Obesity is today a global phenomenon that affects all countries, all types of societies regardless of age, sex, and income. The average value of the relative body mass index (BMI) has increased, which indicates an increasing obesity problem in the population. Nowadays obesity is a global problem, and mass production of clothes is standard size. People have a problem to find best-fitted clothes. The goal of the project is to develop an E-Commerce web portal as a new, innovative and customize clothing production system for obese people. This research has a long-term objective and short-term objective. The long-term objectives are (1) utilize online Web portal to improve tailors’ income, and (2) provide a free online platform to the tailors and customers in order to stitch clothes. Then, the short-term objective are (1) identify e-commerce’s requirements, (2) analyze and design the e-commerce application, and (3) build and implement the e-commerce application to Customized Clothes for Overweight people. This application can hopefully improve the tailors’ income and provide an easy way for customers to choose a fabric, apply style and provide measurement. This e-commerce application is not limited to obese or overweight people but also for other people who want to stitch cloth from tailors. MySQL and PHP we are going to use for developing the application.Keywords: e-commerce, obesity, PHP, customize clothes
Procedia PDF Downloads 34415902 Recurrent Neural Networks with Deep Hierarchical Mixed Structures for Chinese Document Classification
Authors: Zhaoxin Luo, Michael Zhu
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In natural languages, there are always complex semantic hierarchies. Obtaining the feature representation based on these complex semantic hierarchies becomes the key to the success of the model. Several RNN models have recently been proposed to use latent indicators to obtain the hierarchical structure of documents. However, the model that only uses a single-layer latent indicator cannot achieve the true hierarchical structure of the language, especially a complex language like Chinese. In this paper, we propose a deep layered model that stacks arbitrarily many RNN layers equipped with latent indicators. After using EM and training it hierarchically, our model solves the computational problem of stacking RNN layers and makes it possible to stack arbitrarily many RNN layers. Our deep hierarchical model not only achieves comparable results to large pre-trained models on the Chinese short text classification problem but also achieves state of art results on the Chinese long text classification problem.Keywords: nature language processing, recurrent neural network, hierarchical structure, document classification, Chinese
Procedia PDF Downloads 6815901 Development of a Numerical Model to Predict Wear in Grouted Connections for Offshore Wind Turbine Generators
Authors: Paul Dallyn, Ashraf El-Hamalawi, Alessandro Palmeri, Bob Knight
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In order to better understand the long term implications of the grout wear failure mode in large-diameter plain-sided grouted connections, a numerical model has been developed and calibrated that can take advantage of existing operational plant data to predict the wear accumulation for the actual load conditions experienced over a given period, thus limiting the need for expensive monitoring systems. This model has been derived and calibrated based on site structural condition monitoring (SCM) data and supervisory control and data acquisition systems (SCADA) data for two operational wind turbine generator substructures afflicted with this challenge, along with experimentally derived wear rates.Keywords: grouted connection, numerical model, offshore structure, wear, wind energy
Procedia PDF Downloads 45415900 A “Best Practice” Model for Physical Education in the BRICS Countries
Authors: Vasti Oelofse, Niekie van der Merwe, Dorita du Toit
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This study addresses the need for a unified best practice model for Physical Education across BRICS nations, as current research primarily offers individual country recommendations. Drawing on relevant literature within the framework of Bronfenbrenner’s Ecological Systems Theory, as well as data from open-ended questionnaires completed by Physical Education experts from the BRICS countries, , the study develops a best practice model based on identified challenges and effective practices in Physical Education. A model is proposed that incorporates flexible and resource-efficient strategies tailored to address PE challenges specific to these countries, enhancing outcomes for learners, empowering teachers, and fostering systemic collaboration among BRICS members. The proposed model comprises six key areas: “Curriculum and policy requirements”, “General approach”, “Theoretical basis”, “Strategies for presenting content”, “Teacher training”, and “Evaluation”. The “Strategies for presenting program content” area addresses both well-resourced and poorly resourced schools, adapting curriculum, teaching strategies, materials, and learner activities for varied socio-economic contexts. The model emphasizes a holistic approach to learner development, engaging environments, and continuous teacher training. A collaborative approach among BRICS countries, focusing on shared best practices and continuous improvement, is vital for the model's successful implementation, enhancing Physical Education programs and outcomes across these nations.Keywords: BRICS countries, physical education, best practice model, ecological systems theory
Procedia PDF Downloads 1215899 Seismic Assessment of Old Existing RC Buildings with Masonry Infill in Madinah as Per ASCE
Authors: Tarek M. Alguhane, Ayman H. Khalil, Nour M. Fayed, Ayman M. Ismail
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An existing RC building in Madinah is seismically evaluated with and without infill wall. Four model systems have been considered i. e. model I (no infill), model IIA (strut infill-update from field test), model IIB (strut infill- ASCE/SEI 41) and model IIC (strut infill-Soft storey-ASCE/SEI 41). Three dimensional pushover analyses have been carried out using SAP 2000 software incorporating inelastic material behavior for concrete, steel and infill walls. Infill wall has been modeled as equivalent strut according to suggested equation matching field test measurements and to the ASCE/SEI 41 equation. The effect of building modeling on the performance point as well as capacity and demand spectra due to EQ design spectrum function in Madinah area has been investigated. The response modification factor (R) for the 5 story RC building is evaluated from capacity and demand spectra (ATC-40) for the studied models. The results are summarized and discussed.Keywords: infill wall, pushover analysis, response modification factor, seismic assessment
Procedia PDF Downloads 39315898 Volcanoscape Space Configuration Zoning Based on Disaster Mitigation by Utilizing GIS Platform in Mt. Krakatau Indonesia
Authors: Vega Erdiana Dwi Fransiska, Abyan Rai Fauzan Machmudin
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Particularly, space configuration zoning is the very first juncture of a complete space configuration and region planning. Zoning is aimed to define discrete knowledge based on a local wisdom. Ancient predecessor scientifically study the sign of natural disaster towards ethnography approach by operating this knowledge. There are three main functions of space zoning, which are control function, guidance function, and additional function. The control function refers to an instrument for development control and as one of the essentials in controlling land use. Hence, the guidance function indicates as guidance for proposing operational planning and technical development or land usage. Any additional function is useful as a supplementary for region or province planning details. This phase likewise accredits to define boundary in an open space based on geographical appearance. Informant who is categorized as an elder lives in earthquake prone area, to be precise the area is the surrounding of Mount Krakatau. The collected data is one of method for analyzed with thematic model. Later on, it will be verified. In space zoning, long-range distance sensor is applied to determine visualization of the area, which will be zoned before the step of survey to validate the data. The data, which is obtained from long-range distance sensor and site survey, will be overlaid using GIS Platform. Comparing the knowledge based on a local wisdom that is well known by elderly in that area, some of it is relevant to the research, while the others are not. Based on the site survey, the interpretation of a long-range distance sensor, and determining space zoning by considering various aspects resulted in the pattern map of space zoning. This map can be integrated with disaster mitigation affected by volcano eruption.Keywords: elderly, GIS platform, local wisdom, space zoning
Procedia PDF Downloads 25515897 Numerical Solution of Space Fractional Order Solute Transport System
Authors: Shubham Jaiswal
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In the present article, a drive is taken to compute the solution of spatial fractional order advection-dispersion equation having source/sink term with given initial and boundary conditions. The equation is converted to a system of ordinary differential equations using second-kind shifted Chebyshev polynomials, which have finally been solved using finite difference method. The striking feature of the article is the fast transportation of solute concentration as and when the system approaches fractional order from standard order for specified values of the parameters of the system.Keywords: spatial fractional order advection-dispersion equation, second-kind shifted Chebyshev polynomial, collocation method, conservative system, non-conservative system
Procedia PDF Downloads 26115896 Study of a Fabry-Perot Resonator
Authors: F. Hadjaj, A. Belghachi, A. Halmaoui, M. Belhadj, H. Mazouz
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A laser is essentially an optical oscillator consisting of a resonant cavity, an amplifying medium and a pumping source. In semiconductor diode lasers, the cavity is created by the boundary between the cleaved face of the semiconductor crystal and air and also has reflective properties as a result of the differing refractive indices of the two media. For a GaAs-air interface a reflectance of 0.3 is typical and therefore the length of the semiconductor junction forms the resonant cavity. To prevent light, being emitted in unwanted directions from the junction and Sides perpendicular to the required direction are roughened. The objective of this work is to simulate the optical resonator Fabry-Perot and explore its main characteristics, such as FSR, Finesse, Linewidth, Transmission and so on that describe the performance of resonator.Keywords: Fabry-Perot Resonator, laser diod, reflectance, semiconductor
Procedia PDF Downloads 35215895 Scorbot-ER 4U Using Forward Kinematics Modelling and Analysis
Authors: D. Maneetham, L. Sivhour
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Robotic arm manipulators are widely used to accomplish many kinds of tasks. SCORBOT-ER 4u is a 5-degree of freedom (DOF) vertical articulated educational robotic arm, and all joints are revolute. It is specifically designed to perform pick and place task with its gripper. The pick and place task consists of consideration of the end effector coordinate of the robotic arm and the desired position coordinate in its workspace. This paper describes about forward kinematics modeling and analysis of the robotic end effector motion through joint space. The kinematics problems are defined by the transformation from the Cartesian space to the joint space. Denavit-Hartenberg (D-H) model is used in order to model the robotic links and joints with 4x4 homogeneous matrix. The forward kinematics model is also developed and simulated in MATLAB. The mathematical model is validated by using robotic toolbox in MATLAB. By using this method, it may be applicable to get the end effector coordinate of this robotic arm and other similar types to this arm. The software development of SCORBOT-ER 4u is also described here. PC-and EtherCAT based control technology from BECKHOFF is used to control the arm to express the pick and place task.Keywords: forward kinematics, D-H model, robotic toolbox, PC- and EtherCAT-based control
Procedia PDF Downloads 17915894 Disowning of ‘Our Lady of Alice Bhatti’ by Mohammad Hanif Through Gendered and Religious Discourse
Authors: Abrar Ajmal
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The language used in literature reveals the culture and social gestalt of any society in which it has been constructed and consumed. This paper carries the same rationale, which aims to track certain socio-religious and cultural-economic disparities and discrepancies towards minorities, particularly Christians, in an Islamic re(public) where there is a clear majority of Muslims with the help of analysis of instances of language used in the narratives “Our Lady of Alice Bhatt” by Mohammad Hanif. It would highlight social inequalities practiced deeply in sociocultural discourse. Moreover, this research would also touch upon the question of gender discrimination and gender construction as a female entity in a male-chauvinistic scenic turnout using language since the novel revolves around communicative forfeits of Alice Bhatti’s life where she is fraying in fisticuffs to befit herself in a miss-fitted society. It would employ using Fairclough's framework for analysis to conduct a critical discourse analysis of the text at three axiom levels namely textual analysis, discursive practices, and socio-cultural analysis. Thus, the results would reveal textual findings in linguistic analysis, a range of embedded discourses in discursive practices, and consumption of the text into socio-cultural explications with the use of language and lexicalization employed in the selected excerpts.Keywords: gendered discourse, socio-economic disparities minorities, Islamization, analytical framework
Procedia PDF Downloads 5915893 Development of the Academic Model to Predict Student Success at VUT-FSASEC Using Decision Trees
Authors: Langa Hendrick Musawenkosi, Twala Bhekisipho
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The success or failure of students is a concern for every academic institution, college, university, governments and students themselves. Several approaches have been researched to address this concern. In this paper, a view is held that when a student enters a university or college or an academic institution, he or she enters an academic environment. The academic environment is unique concept used to develop the solution for making predictions effectively. This paper presents a model to determine the propensity of a student to succeed or fail in the French South African Schneider Electric Education Center (FSASEC) at the Vaal University of Technology (VUT). The Decision Tree algorithm is used to implement the model at FSASEC.Keywords: FSASEC, academic environment model, decision trees, k-nearest neighbor, machine learning, popularity index, support vector machine
Procedia PDF Downloads 20015892 Analytical Modeling of Drain Current for DNA Biomolecule Detection in Double-Gate Tunnel Field-Effect Transistor Biosensor
Authors: Ashwani Kumar
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Abstract- This study presents an analytical modeling approach for analyzing the drain current behavior in Tunnel Field-Effect Transistor (TFET) biosensors used for the detection of DNA biomolecules. The proposed model focuses on elucidating the relationship between the drain current and the presence of DNA biomolecules, taking into account the impact of various device parameters and biomolecule characteristics. Through comprehensive analysis, the model offers insights into the underlying mechanisms governing the sensing performance of TFET biosensors, aiding in the optimization of device design and operation. A non-local tunneling model is incorporated with other essential models to accurately trace the simulation and modeled data. An experimental validation of the model is provided, demonstrating its efficacy in accurately predicting the drain current response to DNA biomolecule detection. The sensitivity attained from the analytical model is compared and contrasted with the ongoing research work in this area.Keywords: biosensor, double-gate TFET, DNA detection, drain current modeling, sensitivity
Procedia PDF Downloads 5715891 Component Lifecycle and Concurrency Model in Usage Control (UCON) System
Authors: P. Ghann, J. Shiguang, C. Zhou
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Access control is one of the most challenging issues facing information security. Access control is defined as, the ability to permit or deny access to a particular computational resource or digital information by an unauthorized user or subject. The concept of usage control (UCON) has been introduced as a unified approach to capture a number of extensions for access control models and systems. In UCON, an access decision is determined by three factors: Authorizations, obligations and conditions. Attribute mutability and decision continuity are two distinct characteristics introduced by UCON for the first time. An observation of UCON components indicates that, the components are predefined and static. In this paper, we propose a new and flexible model of usage control for the creation and elimination of some of these components; for example new objects, subjects, attributes and integrate these with the original UCON model. We also propose a model for concurrent usage scenarios in UCON.Keywords: access control, concurrency, digital container, usage control
Procedia PDF Downloads 32115890 The Concept of an Agile Enterprise Research Model
Authors: Maja Sajdak
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The aim of this paper is to present the concept of an agile enterprise model and to initiate discussion on the research assumptions of the model presented. The implementation of the research project "The agility of enterprises in the process of adapting to the environment and its changes" began in August 2014 and is planned to last three years. The article has the form of a work-in-progress paper which aims to verify and initiate a debate over the proposed research model. In the literature there are very few publications relating to research into agility; it can be concluded that the most controversial issue in this regard is the method of measuring agility. In previous studies the operationalization of agility was often fragmentary, focusing only on selected areas of agility, for example manufacturing, or analysing only selected sectors. As a result the measures created to date can only be treated as contributory to the development of precise measurement tools. This research project aims to fill a cognitive gap in the literature with regard to the conceptualization and operationalization of an agile company. Thus, the original contribution of the author of this project is the construction of a theoretical model that integrates manufacturing agility (consisting mainly in adaptation to the environment) and strategic agility (based on proactive measures). The author of this research project is primarily interested in the attributes of an agile enterprise which indicate that the company is able to rapidly adapt to changing circumstances and behave pro-actively.Keywords: agile company, acuity, entrepreneurship, flexibility, research model, strategic leadership
Procedia PDF Downloads 34415889 Utilization of Schnerr-Sauer Cavitation Model for Simulation of Cavitation Inception and Super Cavitation
Authors: Mohammadreza Nezamirad, Azadeh Yazdi, Sepideh Amirahmadian, Nasim Sabetpour, Amirmasoud Hamedi
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In this study, the Reynolds-Stress-Navier-Stokes framework is utilized to investigate the flow inside the diesel injector nozzle. The flow is assumed to be multiphase as the formation of vapor by pressure drop is visualized. For pressure and velocity linkage, the coupled algorithm is used. Since the cavitation phenomenon inherently is unsteady, the quasi-steady approach is utilized for saving time and resources in the current study. Schnerr-Sauer cavitation model is used, which was capable of predicting flow behavior both at the initial and final steps of the cavitation process. Two different turbulent models were used in this study to clarify which one is more capable in predicting cavitation inception and super-cavitation. It was found that K-ε was more compatible with the Shnerr-Sauer cavitation model; therefore, the mentioned model is used for the rest of this study.Keywords: CFD, RANS, cavitation, fuel, injector
Procedia PDF Downloads 20915888 Estimation of Solar Radiation Power Using Reference Evaluation of Solar Transmittance, 2 Bands Model: Case Study of Semarang, Central Java, Indonesia
Authors: Benedictus Asriparusa
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Solar radiation is a green renewable energy which has the potential to answer the needs of energy problems on the period. Knowing how to estimate the strength of the solar radiation force may be one solution of sustainable energy development in an integrated manner. Unfortunately, a fairly extensive area of Indonesia is still very low availability of solar radiation data. Therefore, we need a method to estimate the exact strength of solar radiation. In this study, author used a model Reference Evaluation of Solar Transmittance, 2 Bands (REST 2). Validation of REST 2 model has been performed in Spain, India, Colorado, Saudi Arabia, and several other areas. But it is not widely used in Indonesia. Indonesian region study area is represented by the area of Semarang, Central Java. Solar radiation values estimated using REST 2 model was then verified by field data and gives average RMSE value of 6.53%. Based on the value, it can be concluded that the model REST 2 can be used to estimate the value of solar radiation in clear sky conditions in parts of Indonesia.Keywords: estimation, solar radiation power, REST 2, solar transmittance
Procedia PDF Downloads 42715887 Dynamic Shock Bank Liquidity Analysis
Authors: C. Recommandé, J. C. Blind, A. Clavel, R. Gourichon, V. Le Gal
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Simulations are developed in this paper with usual DSGE model equations. The model is based on simplified version of Smets-Wouters equations in use at European Central Bank which implies 10 macro-economic variables: consumption, investment, wages, inflation, capital stock, interest rates, production, capital accumulation, labour and credit rate, and allows take into consideration the banking system. Throughout the simulations, this model will be used to evaluate the impact of rate shocks recounting the actions of the European Central Bank during 2008.Keywords: CC-LM, Central Bank, DSGE, liquidity shock, non-standard intervention
Procedia PDF Downloads 45815886 Optimization of Sequential Thermophilic Bio-Hydrogen/Methane Production from Mono-Ethylene Glycol via Anaerobic Digestion: Impact of Inoculum to Substrate Ratio and N/P Ratio
Authors: Ahmed Elreedy, Ahmed Tawfik
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This investigation aims to assess the effect of inoculum to substrate ratio (ISR) and nitrogen to phosphorous balance on simultaneous biohydrogen and methane production from anaerobic decomposition of mono-ethylene glycol (MEG). Different ISRs were applied in the range between 2.65 and 13.23 gVSS/gCOD, whereas the tested N/P ratios were changed from 4.6 to 8.5; both under thermophilic conditions (55°C). The maximum obtained methane and hydrogen yields (MY and HY) of 151.86±10.8 and 22.27±1.1 mL/gCODinitial were recorded at ISRs of 5.29 and 3.78 gVSS/gCOD, respectively. Unlikely, the ammonification process, in terms of net ammonia produced, was found to be ISR and COD/N ratio dependent, reaching its peak value of 515.5±31.05 mgNH4-N/L at ISR and COD/N ratio of 13.23 gVSS/gCOD and 11.56. The optimum HY was enhanced by more than 1.45-fold with declining N/P ratio from 8.5 to 4.6; whereas, the MY was improved (1.6-fold), while increasing N/P ratio from 4.6 to 5.5 with no significant impact at N/P ratio of 8.5. The results obtained revealed that the methane production was strongly influenced by initial ammonia, compared to initial phosphate. Likewise, the generation of ammonia was markedly deteriorated from 535.25±41.5 to 238.33±17.6 mgNH4-N/L with increasing N/P ratio from 4.6 to 8.5. The kinetic study using Modified Gompertz equation was successfully fitted to the experimental outputs (R2 > 0.9761).Keywords: mono-ethylene glycol, biohydrogen and methane, inoculum to substrate ratio, nitrogen to phosphorous balance, ammonification
Procedia PDF Downloads 38215885 Transmission Line Matrix (TLM) Modelling of Microstrip Circular Antenna
Authors: Jugoslav Jokovic, Tijana Dimitrijevic, Nebojsa Doncov
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The goal of this paper is to investigate the possibilities and effectiveness of the TLM (Transmission Line Matrix) method for modelling of up-to-date microstrip antennas with circular geometry that have significant application in modern wireless communication systems. The coaxially fed microstrip antenna configurations with circular patch are analyzed by using the in-house 3DTLMcyl_cw solver based on computational electromagnetic TLM method adapted to the cylindrical grid and enhanced with the compact wire model. Opposed to the widely used rectangular TLM mesh, where a staircase approximation has to be used to describe curved boundaries, precise modelling of circular boundaries can be accomplished in the cylindrical grid irrespective of the mesh resolution. Using the compact wire model incorporated in cylindrical mesh, it is possible to model coaxial feed and include the influence of the real excitation in the antenna model. The conventional and inverted configuration of a coaxially fed circular patch antenna are considered, comparing the resonances obtained using TLM cylindrical model with results reached by the corresponding model in a rectangular grid as well as with experimental ones. Bearing in mind that accuracy of simulated results depends on a relevantly created model, besides structure geometry and dimensions, it is important to consider additional modelling issues, regarding appropriate mesh resolution and a relevant extension of a mesh around the considered structure that would provide convergence of the results.Keywords: computational electromagnetic, coaxial feed, microstrip antenna, TLM modelling
Procedia PDF Downloads 28015884 Complex Dynamics of a Four Species Food-Web Model: An Analysis through Beddington-Deangelis Functional Response in the Presence of Additional Food
Authors: Surbhi Rani, Sunita Gakkhar
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The four-dimensional food web system consisting of two prey species for a generalist middle predator and a top predator is proposed and investigated. The middle predator is predating both the prey species with a modified Holling type-II functional response. The food web model is found to be well-posed, bounded, and dissipative. The proposed model's essential dynamical features are studied in terms of local stability. The four species' survival is explored, and persistence conditions are established. The numerical simulations reveal the persistence in the form of a chaotic attractor or stable focus. The conclusion is that providing additional food to the middle predator may help to control the food chain's chaos.Keywords: predator-prey model, existence of equilibrium points, local stability, chaos, numerical simulations
Procedia PDF Downloads 10915883 Modeling of Bipolar Charge Transport through Nanocomposite Films for Energy Storage
Authors: Meng H. Lean, Wei-Ping L. Chu
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The effects of ferroelectric nanofiller size, shape, loading, and polarization, on bipolar charge injection, transport, and recombination through amorphous and semicrystalline polymers are studied. A 3D particle-in-cell model extends the classical electrical double layer representation to treat ferroelectric nanoparticles. Metal-polymer charge injection assumes Schottky emission and Fowler-Nordheim tunneling, migration through field-dependent Poole-Frenkel mobility, and recombination with Monte Carlo selection based on collision probability. A boundary integral equation method is used for solution of the Poisson equation coupled with a second-order predictor-corrector scheme for robust time integration of the equations of motion. The stability criterion of the explicit algorithm conforms to the Courant-Friedrichs-Levy limit. Trajectories for charge that make it through the film are curvilinear paths that meander through the interspaces. Results indicate that charge transport behavior depends on nanoparticle polarization with anti-parallel orientation showing the highest leakage conduction and lowest level of charge trapping in the interaction zone. Simulation prediction of a size range of 80 to 100 nm to minimize attachment and maximize conduction is validated by theory. Attached charge fractions go from 2.2% to 97% as nanofiller size is decreased from 150 nm to 60 nm. Computed conductivity of 0.4 x 1014 S/cm is in agreement with published data for plastics. Charge attachment is increased with spheroids due to the increase in surface area, and especially so for oblate spheroids showing the influence of larger cross-sections. Charge attachment to nanofillers and nanocrystallites increase with vol.% loading or degree of crystallinity, and saturate at about 40 vol.%.Keywords: nanocomposites, nanofillers, electrical double layer, bipolar charge transport
Procedia PDF Downloads 35415882 Developing a Model of Teaching Writing Based On Reading Approach through Reflection Strategy for EFL Students of STKIP YPUP
Authors: Eny Syatriana, Ardiansyah
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The purpose of recent study was to develop a learning model on writing, based on the reading texts which will be read by the students using reflection strategy. The strategy would allow the students to read the text and then they would write back the main idea and to develop the text by using their own sentences. So, the writing practice was begun by reading an interesting text, then the students would develop the text which has been read into their writing. The problem questions are (1) what kind of learning model that can develop the students writing ability? (2) what is the achievement of the students of STKIP YPUP through reflection strategy? (3) is the using of the strategy effective to develop students competence In writing? (4) in what level are the students interest toward the using of a strategy In writing subject? This development research consisted of some steps, they are (1) need analysis (2) model design (3) implementation (4) model evaluation. The need analysis was applied through discussion among the writing lecturers to create a learning model for writing subject. To see the effectiveness of the model, an experiment would be delivered for one class. The instrument and learning material would be validated by the experts. In every steps of material development, there was a learning process, where would be validated by an expert. The research used development design. These Principles and procedures or research design and development .This study, researcher would do need analysis, creating prototype, content validation, and limited empiric experiment to the sample. In each steps, there should be an assessment and revision to the drafts before continue to the next steps. The second year, the prototype would be tested empirically to four classes in STKIP YPUP for English department. Implementing the test greatly was done through the action research and followed by evaluation and validation from the experts.Keywords: learning model, reflection, strategy, reading, writing, development
Procedia PDF Downloads 36515881 General Architecture for Automation of Machine Learning Practices
Authors: U. Borasi, Amit Kr. Jain, Rakesh, Piyush Jain
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Data collection, data preparation, model training, model evaluation, and deployment are all processes in a typical machine learning workflow. Training data needs to be gathered and organised. This often entails collecting a sizable dataset and cleaning it to remove or correct any inaccurate or missing information. Preparing the data for use in the machine learning model requires pre-processing it after it has been acquired. This often entails actions like scaling or normalising the data, handling outliers, selecting appropriate features, reducing dimensionality, etc. This pre-processed data is then used to train a model on some machine learning algorithm. After the model has been trained, it needs to be assessed by determining metrics like accuracy, precision, and recall, utilising a test dataset. Every time a new model is built, both data pre-processing and model training—two crucial processes in the Machine learning (ML) workflow—must be carried out. Thus, there are various Machine Learning algorithms that can be employed for every single approach to data pre-processing, generating a large set of combinations to choose from. Example: for every method to handle missing values (dropping records, replacing with mean, etc.), for every scaling technique, and for every combination of features selected, a different algorithm can be used. As a result, in order to get the optimum outcomes, these tasks are frequently repeated in different combinations. This paper suggests a simple architecture for organizing this largely produced “combination set of pre-processing steps and algorithms” into an automated workflow which simplifies the task of carrying out all possibilities.Keywords: machine learning, automation, AUTOML, architecture, operator pool, configuration, scheduler
Procedia PDF Downloads 5815880 Modeling Breathable Particulate Matter Concentrations over Mexico City Retrieved from Landsat 8 Satellite Imagery
Authors: Rodrigo T. Sepulveda-Hirose, Ana B. Carrera-Aguilar, Magnolia G. Martinez-Rivera, Pablo de J. Angeles-Salto, Carlos Herrera-Ventosa
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In order to diminish health risks, it is of major importance to monitor air quality. However, this process is accompanied by the high costs of physical and human resources. In this context, this research is carried out with the main objective of developing a predictive model for concentrations of inhalable particles (PM10-2.5) using remote sensing. To develop the model, satellite images, mainly from Landsat 8, of the Mexico City’s Metropolitan Area were used. Using historical PM10 and PM2.5 measurements of the RAMA (Automatic Environmental Monitoring Network of Mexico City) and through the processing of the available satellite images, a preliminary model was generated in which it was possible to observe critical opportunity areas that will allow the generation of a robust model. Through the preliminary model applied to the scenes of Mexico City, three areas were identified that cause great interest due to the presumed high concentration of PM; the zones are those that present high plant density, bodies of water and soil without constructions or vegetation. To date, work continues on this line to improve the preliminary model that has been proposed. In addition, a brief analysis was made of six models, presented in articles developed in different parts of the world, this in order to visualize the optimal bands for the generation of a suitable model for Mexico City. It was found that infrared bands have helped to model in other cities, but the effectiveness that these bands could provide for the geographic and climatic conditions of Mexico City is still being evaluated.Keywords: air quality, modeling pollution, particulate matter, remote sensing
Procedia PDF Downloads 15515879 Optimizing Scribe Resourcing to Improve Hospitalist Workloads
Authors: Ahmed Hamzi, Bryan Norman
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Having scribes help document patient records in electronic health record systems can improve hospitalists’ productivity. But hospitals need to determine the optimum number of scribes to hire to maximize scribe cost effectiveness. Scribe attendance uncertainty due to planned and unplanned absences is a primary challenge. This paper presents simulation and analytical models to determine the optimum number of scribes for a hospital to hire. Scribe staffing practices vary from one context to another; different staffing scenarios are considered where having extra attending scribes provides or does not provide additional value and utilizing on-call scribes to fill in for potentially absent scribes. These staffing scenarios are assessed for different scribe revenue ratios (ratio of the value of the scribe relative to scribe costs) ranging from 100% to 300%. The optimum solution depends on the absenteeism rate, revenue ratio, and desired service level. The analytical model obtains solutions easier and faster than the simulation model, but the simulation model is more accurate. Therefore, the analytical model’s solutions are compared with the simulation model’s solutions regarding both the number of scribes hired and cost-effectiveness. Additionally, an Excel tool has been developed to facilitate decision-makers in easily obtaining solutions using the analytical model.Keywords: hospitalists, workload, optimization cost, economic analysis
Procedia PDF Downloads 4515878 Motion Performance Analyses and Trajectory Planning of the Movable Leg-Foot Lander
Authors: Shan Jia, Jinbao Chen, Jinhua Zhou, Jiacheng Qian
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In response to the functional limitations of the fixed landers, those are to expand the detection range by the use of wheeled rovers with unavoidable path-repeatability in deep space exploration currently, a movable lander based on the leg-foot walking mechanism is presented. Firstly, a quadruped landing mechanism based on pushrod-damping is proposed. The configuration is of the bionic characteristics such as hip, knee and ankle joints, and the multi-function main/auxiliary buffers based on the crumple-energy absorption and screw-nut mechanism. Secondly, the workspace of the end of the leg-foot mechanism is solved by Monte Carlo method, and the key points on the desired trajectory of the end of the leg-foot mechanism are fitted by cubic spline curve. Finally, an optimal time-jerk trajectory based on weight coefficient is planned and analyzed by an adaptive genetic algorithm (AGA). The simulation results prove the rationality and stability of walking motion of the movable leg-foot lander in the star catalogue. In addition, this research can also provide a technical solution integrating of soft-landing, large-scale inspection and material transfer for future star catalogue exploration, and can even serve as the technical basis for developing the reusable landers.Keywords: motion performance, trajectory planning, movable, leg-foot lander
Procedia PDF Downloads 13915877 Non-Linear Behavior of Granular Materials in Pavement Design
Authors: Mounir Tichamakdj, Khaled Sandjak, Boualem Tiliouine
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The design of flexible pavements is currently carried out using a multilayer elastic theory. However, for thin-surface pavements subject to light or medium traffic volumes, the importance of the non-linear stress-strain behavior of unbound granular materials requires the use of more sophisticated numerical models for the structural design of these pavements. The simplified analysis of the nonlinear behavior of granular materials in pavement design will be developed in this study. To achieve this objective, an equivalent linear model derived from a volumetric shear stress model is used to simulate the nonlinear elastic behavior of two unlinked local granular materials often used in pavements. This model is included here to adequately incorporate material non-linearity due to stress dependence and stiffness of the granular layers in the flexible pavement analysis. The sensitivity of the pavement design criteria to the likely variations in asphalt layer thickness and the mineralogical nature of unbound granular materials commonly used in pavement structures are also evaluated.Keywords: granular materials, linear equivalent model, non-linear behavior, pavement design, shear volumetric strain model
Procedia PDF Downloads 17815876 Innovation and Economic Growth Model of East Asian Countries: The Adaptability of the Model in Ethiopia
Authors: Khalid Yousuf Ahmed
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At the beginning of growth period, East Asian countries achieved impressive economic growth for the decades. They transformed from agricultural economy toward industrialization and contributed to dynamic structural transformation. The achievements were driven by government-led development policies that implemented effective innovation policy to boost technological capability of local firms. Recently, most Sub-Saharan African have been showing sustainable growth. Exceptionally, Ethiopia has been recording double-digit growth for a decade. Hence, Ethiopia has claimed to follow the footstep of East Asia development model. The study is going to examine whether Ethiopia can replicate innovation and economic growth model of East Asia by using Japan, Taiwan, South Korea and China as a case to illustrate their model of growth. This research will be based on empirical data gathering and extended theory of national innovation system and economic growth theory. Moreover, the methodology is based on Knowledge Assessment Methodology (KAM) and also employing cross-countries regression analysis. The results explained that there is a significant relationship between innovation indicators and economic growth in East Asian countries while the relationship is non-existing for Ethiopia except implementing similar policies and achieving similar growth trend. Therefore, Ethiopia needs to introduce inclusive policies that give priority to improving human capital and invest on the knowledge-based economy to replicate East Asian Model.Keywords: economic growth, FDI, endogenous growth theory, East Asia model
Procedia PDF Downloads 275