Search results for: system dynamics
18396 Biosignal Recognition for Personal Identification
Authors: Hadri Hussain, M.Nasir Ibrahim, Chee-Ming Ting, Mariani Idroas, Fuad Numan, Alias Mohd Noor
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A biometric security system has become an important application in client identification and verification system. A conventional biometric system is normally based on unimodal biometric that depends on either behavioural or physiological information for authentication purposes. The behavioural biometric depends on human body biometric signal (such as speech) and biosignal biometric (such as electrocardiogram (ECG) and phonocardiogram or heart sound (HS)). The speech signal is commonly used in a recognition system in biometric, while the ECG and the HS have been used to identify a person’s diseases uniquely related to its cluster. However, the conventional biometric system is liable to spoof attack that will affect the performance of the system. Therefore, a multimodal biometric security system is developed, which is based on biometric signal of ECG, HS, and speech. The biosignal data involved in the biometric system is initially segmented, with each segment Mel Frequency Cepstral Coefficients (MFCC) method is exploited for extracting the feature. The Hidden Markov Model (HMM) is used to model the client and to classify the unknown input with respect to the modal. The recognition system involved training and testing session that is known as client identification (CID). In this project, twenty clients are tested with the developed system. The best overall performance at 44 kHz was 93.92% for ECG and the worst overall performance was ECG at 88.47%. The results were compared to the best overall performance at 44 kHz for (20clients) to increment of clients, which was 90.00% for HS and the worst overall performance falls at ECG at 79.91%. It can be concluded that the difference multimodal biometric has a substantial effect on performance of the biometric system and with the increment of data, even with higher frequency sampling, the performance still decreased slightly as predicted.Keywords: electrocardiogram, phonocardiogram, hidden markov model, mel frequency cepstral coeffiecients, client identification
Procedia PDF Downloads 28318395 Dynamic Fault Tree Analysis of Dynamic Positioning System through Monte Carlo Approach
Authors: A. S. Cheliyan, S. K. Bhattacharyya
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Dynamic Positioning System (DPS) is employed in marine vessels of the offshore oil and gas industry. It is a computer controlled system to automatically maintain a ship’s position and heading by using its own thrusters. Reliability assessment of the same can be analyzed through conventional fault tree. However, the complex behaviour like sequence failure, redundancy management and priority of failing of events cannot be analyzed by the conventional fault trees. The Dynamic Fault Tree (DFT) addresses these shortcomings of conventional Fault Tree by defining additional gates called dynamic gates. Monte Carlo based simulation approach has been adopted for the dynamic gates. This method of realistic modeling of DPS gives meaningful insight into the system reliability and the ability to improve the same.Keywords: dynamic positioning system, dynamic fault tree, Monte Carlo simulation, reliability assessment
Procedia PDF Downloads 77818394 Numerical Simulation of Lifeboat Launching Using Overset Meshing
Authors: Alok Khaware, Vinay Kumar Gupta, Jean Noel Pederzani
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Lifeboat launching from marine vessel or offshore platform is one of the important areas of research in offshore applications. With the advancement of computational fluid dynamic simulation (CFD) technology to solve fluid induced motions coupled with Six Degree of Freedom (6DOF), rigid body dynamics solver, it is now possible to predict the motion of the lifeboat precisely in different challenging conditions. Traditionally dynamic remeshing approach is used to solve this kind of problems, but remeshing approach has some bottlenecks to control good quality mesh in transient moving mesh cases. In the present study, an overset method with higher-order interpolation is used to simulate a lifeboat launched from an offshore platform into calm water, and volume of fluid (VOF) method is used to track free surface. Overset mesh consists of a set of overlapping component meshes, which allows complex geometries to be meshed with lesser effort. Good quality mesh with local refinement is generated at the beginning of the simulation and stay unchanged throughout the simulation. Overset mesh accuracy depends on the precise interpolation technique; the present study includes a robust and accurate least square interpolation method and results obtained with overset mesh shows good agreement with experiment.Keywords: computational fluid dynamics, free surface flow, lifeboat launching, overset mesh, volume of fluid
Procedia PDF Downloads 28018393 Interactive Image Search for Mobile Devices
Authors: Komal V. Aher, Sanjay B. Waykar
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Nowadays every individual having mobile device with them. In both computer vision and information retrieval Image search is currently hot topic with many applications. The proposed intelligent image search system is fully utilizing multimodal and multi-touch functionalities of smart phones which allows search with Image, Voice, and Text on mobile phones. The system will be more useful for users who already have pictures in their minds but have no proper descriptions or names to address them. The paper gives system with ability to form composite visual query to express user’s intention more clearly which helps to give more precise or appropriate results to user. The proposed algorithm will considerably get better in different aspects. System also uses Context based Image retrieval scheme to give significant outcomes. So system is able to achieve gain in terms of search performance, accuracy and user satisfaction.Keywords: color space, histogram, mobile device, mobile visual search, multimodal search
Procedia PDF Downloads 37218392 Relationship Between Behavioral Inhibition/Approach System, and Perceived Stress, With White Blood Cell In Multiple Sclerosis Patients
Authors: Amin Alvani
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Multiple sclerosis (MS) is a chronic, often disabling disease in which the immune system attacks the myelin sheath of neurons in the central nervous system. The present study aimed to investigate the Relationship between behavioral inhibition/approach system (BIS-BAS) and perceived stress (PS) whit control white blood cell (WBC). 60 MS patients (male=36.7, female=63.3%; age range=15-65 participated in the study and completed the demographic questionnaire, the count blood cell (CBC) test, the behavioral Activation and behavioral inhibition scale (BIS-BAS), and the perceived stress Questionnaire (PSS-14). The results revealed that Between of BAS-reward responsiveness (BAS-DR) subscale and PS, in more than MS patient (BIS), there are increase WBC.Keywords: behavioral inhibition/approach system, perceived stress, white blood cell, multiple sclerosis
Procedia PDF Downloads 9418391 Multifluid Computational Fluid Dynamics Simulation for Sawdust Gasification inside an Industrial Scale Fluidized Bed Gasifier
Authors: Vasujeet Singh, Pruthiviraj Nemalipuri, Vivek Vitankar, Harish Chandra Das
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For the correct prediction of thermal and hydraulic performance (bed voidage, suspension density, pressure drop, heat transfer, and combustion kinetics), one should incorporate the correct parameters in the computational fluid dynamics simulation of a fluidized bed gasifier. Scarcity of fossil fuels, and to fulfill the energy demand of the increasing population, researchers need to shift their attention to the alternative to fossil fuels. The current research work focuses on hydrodynamics behavior and gasification of sawdust inside a 2D industrial scale FBG using the Eulerian-Eulerian multifluid model. The present numerical model is validated with experimental data. Further, this model extended for the prediction of gasification characteristics of sawdust by incorporating eight heterogeneous moisture release, volatile cracking, tar cracking, tar oxidation, char combustion, CO₂ gasification, steam gasification, methanation reaction, and five homogeneous oxidation of CO, CH₄, H₂, forward and backward water gas shift (WGS) reactions. In the result section, composition of gasification products is analyzed, along with the hydrodynamics of sawdust and sand phase, heat transfer between the gas, sand and sawdust, reaction rates of different homogeneous and heterogeneous reactions is being analyzed along the height of the domain.Keywords: devolatilization, Eulerian-Eulerian, fluidized bed gasifier, mathematical modelling, sawdust gasification
Procedia PDF Downloads 10918390 Establishing Student Support Strategies for Virtual Learning in Learning Management System Based on Grounded Theory
Authors: Farhad Shafiepour Motlagh, Narges Salehi
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Purpose: The purpose of this study was to support student strategies for virtual learning in the learning management system. Methodology: The research method was based on grounded theory. The statistical population included all the articles of the ten years 2022-2010, and the sampling method was purposeful to the extent of theoretical saturation (n=31 ). Data collection was done by referring to the authoritative scientific databases of Emerald, Springer, Elsevier, Google Scholar, Sage Publication, and Science Direct. For data analysis, open coding, axial coding, and selective coding were used. Results: The results showed that causal conditions include cognitive empowerment (comprehension, analysis, composition), emotional empowerment (learning motivation, involvement in the learning system, enthusiasm for learning), psychomotor empowerment (learning to master, internalizing learning skills, creativity in learning). Conclusion: Supporting students requires their empowerment in three dimensions: cognitive, emotional empowerment, and psychomotor empowerment. In such a way that by introducing them to enter the learning management system, the capacities of the system, the toolkit of learning in the system, improve the motivation to learn in them, and in such a case, by learning more in the learning management system, they will reach mastery learning.Keywords: student support, virtual education, learning management system, electronic
Procedia PDF Downloads 30918389 Periodical System of Isotopes
Authors: Andriy Magula
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With the help of a special algorithm being the principle of multilevel periodicity, the periodic change of properties at the nuclear level of chemical elements was discovered and the variant for the periodic system of isotopes was presented. The periodic change in the properties of isotopes, as well as the vertical symmetry of subgroups, was checked for consistency in accordance with the following ten types of experimental data: mass ratio of fission fragments; quadrupole moment values; magnetic moment; lifetime of radioactive isotopes; neutron scattering; thermal neutron radiative capture cross-sections (n, γ); α-particle yield cross-sections (n, α); isotope abundance on Earth, in the Solar system and other stellar systems; features of ore formation and stellar evolution. For all ten cases, the correspondences for the proposed periodic structure of the nucleus were obtained. The system was formed in the usual 2D table, similar to the periodic system of elements, and the mass series of isotopes was divided into 8 periods and 4 types of ‘nuclear’ orbitals: sn, dn, pn, fn. The origin of ‘magic’ numbers as a set of filled charge shells of the nucleus was explained. Due to the isotope system, the periodic structure is shown at a new level of the universe, and the prospects of its practical use are opened up.Keywords: periodic system, isotope, period, subgroup, “nuclear” orbital, nuclear reaction
Procedia PDF Downloads 2318388 Development of the Web-Based Multimedia N-Screen Service System for Cross Platform
Authors: S. Bae, J. Shin, S. Lee
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As the development of smart devices such as Smart TV, Smartphone, Tablet PC, Laptop, the interest in N-Screen Services that can be cross-linked with heterogeneous devices is increasing. N-Screen means User-centric services that can share and constantly watch multimedia contents anytime and anywhere. However, the existing N-Screen system has the limitation that N-Screen system has to implement the application for each platform and device to provide multimedia service. To overcome this limitation, Multimedia N-Screen Service System is proposed through the web, and it is independent of different environments. The combination of Web and cloud computing technologies from this study results in increasing efficiency and reduction in costs.Keywords: N-screen, web, cloud, multimedia
Procedia PDF Downloads 30418387 The Development of Digital Commerce in Community Enterprise Products to Promote the Distribution of Samut Songkhram Province
Authors: Natcha Wattanaprapa, Alongkorn Taengtong, Phachaya Chaiwchan
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This study investigates and promotes the distribution of community enterprise products of Samut Songkhram province by using e-commerce web technology to help distribute the products. This study also aims to develop the information system to be able to operate on multiple platforms and promote the easy usability on smartphones to increase the efficiency and promote the distribution of community enterprise products of Samut Songkhram province in three areas including Baan Saraphi learning center, the learning center of Bang Noi Floating market as well as Bang Nang Li learning center. The main structure consists of spreading the knowledge regarding the tourist attraction in the area of community enterprise, e-commerce system of community enterprise products, and Chatbot. The researcher developed the system into an application form using the software package to create and manage the content on the internet. Connect management system (CMS) word press was used for managing web pages. Add-on CMS word press was used for creating the system of Chatbot, and the database of PHP My Admin was used as the database management system. The evaluation by the experts and users in 5 aspects, including the system efficiency, the accuracy in the operation of the system, the convenience and ease of use of the system, the design, and the promotion of product distribution in Samut Songkhram province by using questionnaires revealed that the result of evaluation in the promotion of product distribution in Samut Songkhram province was the highest with the mean of 4.20. When evaluating the efficiency of the developed system, it was found that the result of system efficiency was the highest level with a mean of 4.10.Keywords: community enterprise, digital commerce, promotion of product distribution, Samut Songkhram province
Procedia PDF Downloads 15318386 Simulation of a Control System for an Adaptive Suspension System for Passenger Vehicles
Authors: S. Gokul Prassad, S. Aakash, K. Malar Mohan
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In the process to cope with the challenges faced by the automobile industry in providing ride comfort, the electronics and control systems play a vital role. The control systems in an automobile monitor various parameters, controls the performances of the systems, thereby providing better handling characteristics. The automobile suspension system is one of the main systems that ensure the safety, stability and comfort of the passengers. The system is solely responsible for the isolation of the entire automobile from harmful road vibrations. Thus, integration of the control systems in the automobile suspension system would enhance its performance. The diverse road conditions of India demand the need of an efficient suspension system which can provide optimum ride comfort in all road conditions. For any passenger vehicle, the design of the suspension system plays a very important role in assuring the ride comfort and handling characteristics. In recent years, the air suspension system is preferred over the conventional suspension systems to ensure ride comfort. In this article, the ride comfort of the adaptive suspension system is compared with that of the passive suspension system. The schema is created in MATLAB/Simulink environment. The system is controlled by a proportional integral differential controller. Tuning of the controller was done with the Particle Swarm Optimization (PSO) algorithm, since it suited the problem best. Ziegler-Nichols and Modified Ziegler-Nichols tuning methods were also tried and compared. Both the static responses and dynamic responses of the systems were calculated. Various random road profiles as per ISO 8608 standard are modelled in the MATLAB environment and their responses plotted. Open-loop and closed loop responses of the random roads, various bumps and pot holes are also plotted. The simulation results of the proposed design are compared with the available passive suspension system. The obtained results show that the proposed adaptive suspension system is efficient in controlling the maximum over shoot and the settling time of the system is reduced enormously.Keywords: automobile suspension, MATLAB, control system, PID, PSO
Procedia PDF Downloads 29718385 Replacing an Old PFN System with a Solid State Modulator without Changing the Klystron Transformer
Authors: Klas Elmquist, Anders Larsson
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Until the year 2000, almost all short pulse modulators in the accelerator world were made with the pulse forming network (PFN) technique. The pulse forming network systems have since then been replaced with solid state modulators that have better efficiency, better stability, and lower cost of ownership, and they are much smaller. In this paper, it is shown that it is possible to replace a pulse forming network system with a solid-state system without changing the klystron tank and the klystron transformer. The solid-state modulator uses semiconductors switching at 1 kV level. A first pulse transformer transforms the voltage up to 10 kV. The 10 kV pulse is finally fed into the original transformer that is placed under the klystron. A flatness of 0.8 percent and stability of 100 PPM is achieved. The test is done with a CPI 8262 type of klystron. It is also shown that it is possible to run such a system with long cables between the transformers. When using this technique, it will be possible to keep original sub-systems like filament systems, vacuum systems, focusing solenoid systems, and cooling systems for the klystron. This will substantially reduce the cost of an upgrade and prolong the life of the klystron system.Keywords: modulator, solid-state, PFN-system, thyratron
Procedia PDF Downloads 13718384 The Impact of a Sustainable Solar System on the Growth of Strawberry Plants in an Agricultural Greenhouse
Authors: Ilham Ihoume, Rachid Tadili, Nora Arbaoui
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This study examines the effects of a solar-based heating system, in a north-south oriented agricultural greenhouse on the development of strawberry plants during winter. This system relies on the circulation of water as a heat transfer fluid in a closed circuit installed on the greenhouse roof to store heat during the day and release it inside at night. A comparative experimental study was conducted in two greenhouses, one experimental with the solar heating system and the other for control without any heating system. Both greenhouses are located on the terrace of the Solar Energy and Environment Laboratory of the Mohammed V University in Rabat, Morocco. The devel-oped heating system consists of a copper coil inserted in double glazing and placed on the roof of the greenhouse, a water pump circulator, a battery, and a photovoltaic solar panel to power the electrical components. This inexpen-sive and environmentally friendly system allows the greenhouse to be heated during the winter and improves its microclimate system. This improvement resulted in an increase in the air temperature inside the experimental green-house by 6 °C and 8 °C, and a reduction in its relative humidity by 23% and 35% compared to the control greenhouse and the ambient air, respectively, throughout the winter. For the agronomic performance, it was observed that the production was 17 days earlier than in the control greenhouse.Keywords: sustainability, solar energy, thermal energy storage., greenhouse heating
Procedia PDF Downloads 4418383 The Interoperability between CNC Machine Tools and Robot Handling Systems Based on an Object-Oriented Framework
Authors: Pouyan Jahanbin, Mahmoud Houshmand, Omid Fatahi Valilai
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A flexible manufacturing system (FMS) is a manufacturing system having the capability of handling the variations of products features that is the result of ever-changing customer demands. The flexibility of the manufacturing systems help to utilize the resources in a more effective manner. However, the control of such systems would be complicated and challenging. FMS needs CNC machines and robots and other resources for establishing the flexibility and enhancing the efficiency of the whole system. Also it needs to integrate the resources to reach required efficiency and flexibility. In order to reach this goal, an integrator framework is proposed in which the machining data of CNC machine tools is received through a STEP-NC file. The interoperability of the system is achieved by the information system. This paper proposes an information system that its data model is designed based on object oriented approach and is implemented through a knowledge-based system. The framework is connected to a database which is filled with robot’s control commands. The framework programs the robots by rules embedded in its knowledge based system. It also controls the interactions of CNC machine tools for loading and unloading actions by robot. As a result, the proposed framework improves the integration of manufacturing resources in Flexible Manufacturing Systems.Keywords: CNC machine tools, industrial robots, knowledge-based systems, manufacturing recourses integration, flexible manufacturing system (FMS), object-oriented data model
Procedia PDF Downloads 46018382 Formulation Policy of Criminal Sanction in Indonesian Criminal Justice System
Authors: Dini Dewi Heniarti
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This One of criminal sanctions that are often imposed by the judge is imprisonment. The issue on the imposition of imprisonment has been subject of contentious debate and criticism among various groups for a long time. In practice, the problematics of imprisonment lead to complicated problems. The impact of the reckless imposition of the imprisonment includes among others overcapacity of the correctional institution and increasing crimes within the correctional facilities. Therefore, there is a need for renewal of the existing condemnation paradigm, considering the developing phenomena associated with the penal imposition. Imprisonment as one element of the Indonesian penal system is an important and integral part of the other elements. The philosophy of the current penal system, which still refers to the Criminal Code, still carries the values of retaliation and fault-finding toward the offender. Therefore, it is important to reconstruct a new thought in order to realize a penal system that is represented in the formulation of a more humanistic criminal sanctionKeywords: criminal code, criminal sanction, Indonesian legal system, reconstruction of thought
Procedia PDF Downloads 22918381 Mathematical Modelling of Wastewater Collection System in Cha-Am Municipality Using PCSWMM
Authors: Thawtar Htun, Kim N. Irvine, Ranjna Jindal
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This study aimed at modelling the wastewater collection system in Cha-Am Municipality using PCSWMM to investigate the quantity of combined sewage delivered to the aeration lagoon treatment system (ALTS). Cha-Am is a small sea resort town in Petchaburi Province located about 175 km southwest of Bangkok and is facing increasing development so it is important to understand current system performance and plan for future build out. PCSWMM was calibrated using observed ALTS inflow data for the period 15 June to 20 July 2015. The model was validated using observed ALTS inflow data for the periods 19 July to 20 October 2015 and 1 October to 31 December 2015, respectively. The 1:1 lines between modeled and observed peak flow and event volume for the calibration events qualitatively showed good correspondence. The r2 values between modeled and observed peak flow (99%) and event volume (89%) also were strong.Keywords: combined sewer system, mathematical modelling, PCSWMM, wastewater collection system
Procedia PDF Downloads 21518380 Evidence-Based Health System Strengthening in Urban India: Drawing Insights from Rapid Assessment Study
Authors: Anisur Rahman, Sabyasachi Behera, Pawan Pathak, Benazir Patil, Rajesh Khanna
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Background: Nearly half of India’s population is expected to reside in urban areas by 2030. The extent to which India's health system can provide for this large and growing city-based population will determine the country's success in achieving universal health coverage and improved national health indices. National Urban Health Mission (NUHM) strive for improving access to primary health care in urban areas. Implementation of NUHM solicits sensitive, effective and sustainable strategies to strengthen the service delivery mechanisms. The Challenge Initiative for Healthy Cities (TCIHC) is working with the Government of India and three provincial states to develop effective service delivery mechanisms for reproductive, maternal, newborn and child health (RMNCH) through a health systems approach for the urban poor. Method: A rapid assessment study was conceptualized and executed to generate evidence in order to address the challenges impeding in functioning of urban health facilities to deliver effective, efficient and equitable health care services in 7 cities spread across two project States viz. Madhya Pradesh and Odisha. Results: The findings of the assessment reflect: 1. The overall ecosystem pertaining to planning and management of public health interventions is not conducive. 2. The challenges regarding population dynamics like migration keeps on influencing the demand-supply-enabling environment triangle for both public and private service providers. 3. Lack of norms for planning and benchmark for service delivery further impedes urban health system as a whole. 4. Operationalization of primary level services have enough potential to meet the demand of slum dwellers at large. 5. Lack of policy driven strategies on how to integrate the NUHM with other thematic areas of Maternal, Newborn & Child Health (MNCH) and Family Planning (FP). 5. The inappropriate capacity building and acute shortage of Human Resources has huge implication on service provisioning and adherence to the service delivery protocols. Conclusion: The findings from rapid assessment are aimed to inform pertinent stakeholders to develop a multiyear city health action plan to strengthen the health systems in order to improve the efficacy of service delivery mechanism in urban settings.Keywords: city health plan, health system, rapid assessment, urban mission
Procedia PDF Downloads 17118379 The Strong Interactions among the Protons
Authors: Yin Rui, Yin Ming, Yang Wang
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This paper presents empirical evidence validating the Lorentz transformation of rotational frames for both inside critical cylinder (ICC) and outside critical cylinder (OCC) configurations, as well as the corresponding transformations of associated physical quantities. These transformations have been applied to derive the electromagnetic field parameters of a spinning charged particle. In our analysis of a two-proton system, we have not only uncovered strong interactions that are 238 times stronger than the electrostatic force but also elucidated the mechanisms underlying its stability and self-sustainable nature. This strong interaction manifests exclusively at distances on the order of 〖10〗^(-15)meters, consistent with the known range of the strong nuclear force. Furthermore, we have extended our analysis to multi-proton systems, specifically examining configurations containing four to seven protons. For these more complex systems, we have derived the strong interaction forces, providing insights into the nuclear dynamics of larger atomic nuclei. Our findings offer a more comprehensive understanding of the nature of strong interactions among protons. This work may have significant implications for advancing our knowledge of nuclear structure and stability and could potentially bridge the gap between electromagnetic and strong nuclear forces within a unified theoretical framework.Keywords: special relativity, Lorentz transformation, strong interactions, particle spin
Procedia PDF Downloads 1718378 Decision Support System for Examination Selection
Authors: Katejarinporn Chaiya, Jarumon Nookong, Nutthapat Kaewrattanapat
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The purposes of this research were to develop and find users’ satisfaction after using the Decision Support System for Examination Selection. This research presents the design of information systems. In order to find the necessary examination of the statistics. Based on the examination of the candidate and then taking the easy difficulty setting statistics applied to the test. In addition, research has also made performance appraisals from experts and user satisfaction. By results of analysis showed that the performance appraisals from experts on the system as a whole and at a good level. mean was 3.44 and S.D. was 0.55 and user satisfaction per system as a whole and the good level mean was 3.37 and S.D. was 0.42 can conclude that effective systems are in a good level. Work has been completed in accordance with the scope of work. The website used developing this project is PHP, MySQL.5.0.45 for database.Keywords: secision support system, examination, PHP, information systems
Procedia PDF Downloads 45518377 Computational Modeling of Heat Transfer from a Horizontal Array Cylinders for Low Reynolds Numbers
Authors: Ovais U. Khan, G. M. Arshed, S. A. Raza, H. Ali
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A numerical model based on the computational fluid dynamics (CFD) approach is developed to investigate heat transfer across a longitudinal row of six circular cylinders. The momentum and energy equations are solved using the finite volume discretization technique. The convective terms are discretized using a second-order upwind methodology, whereas diffusion terms are discretized using a central differencing scheme. The second-order implicit technique is utilized to integrate time. Numerical simulations have been carried out for three different values of free stream Reynolds number (ReD) 100, 200, 300 and two different values of dimensionless longitudinal pitch ratio (SL/D) 1.5, 2.5 to demonstrate the fluid flow and heat transfer behavior. Numerical results are validated with the analytical findings reported in the literature and have been found to be in good agreement. The maximum percentage error in values of the average Nusselt number obtained from the numerical and analytical solutions is in the range of 10% for the free stream Reynolds number up to 300. It is demonstrated that the average Nusselt number for the array of cylinders increases with increasing the free stream Reynolds number and dimensionless longitudinal pitch ratio. The information generated would be useful in the design of more efficient heat exchangers or other fluid systems involving arrays of cylinders.Keywords: computational fluid dynamics, array of cylinders, longitudinal pitch ratio, finite volume method, incompressible navier-stokes equations
Procedia PDF Downloads 8718376 Anonymous Gel-Fluid Transition of Solid Supported Lipids
Authors: Asma Poursoroush
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Solid-supported lipid bilayers are often used as a simple model for studies of biological membranes. The presence of a solid substrate that interacts attractively with lipid head-groups is expected to affect the phase behavior of the supported bilayer. Molecular dynamics simulations of a coarse-grained model are thus performed to investigate the phase behavior of supported one-component lipid bilayer membranes. Our results show that the attraction of the lipid head groups to the substrate leads to a phase behavior that is different from that of a free standing lipid bilayer. In particular, we found that the phase behaviors of the two leaflets are decoupled in the presence of a substrate. The proximal leaflet undergoes a clear gel-to-fluid phase transition at a temperature lower than that of a free standing bilayer, and that decreases with increasing strength of the substrate-lipid attraction. The distal leaflet, however, undergoes a change from a homogeneous liquid phase at high temperatures to a heterogeneous state consisting of small liquid and gel domains, with the average size of the gel domains that increases with decreasing temperature. While the chain order parameter of the proximal leaflet clearly shows a gel-fluid phase transition, the chain order parameter of the distal leaflet does not exhibit a clear phase transition. The decoupling in the phase behavior of the two leaflets is due to a non-symmteric lipid distribution in the two leaflets resulting from the presence of the substrate.Keywords: membrane, substrate, molecular dynamics, simulation
Procedia PDF Downloads 19918375 Measurement of Solids Concentration in Hydrocyclone Using ERT: Validation Against CFD
Authors: Vakamalla Teja Reddy, Narasimha Mangadoddy
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Hydrocyclones are used to separate particles into different size fractions in the mineral processing, chemical and metallurgical industries. High speed video imaging, Laser Doppler Anemometry (LDA), X-ray and Gamma ray tomography are previously used to measure the two-phase flow characteristics in the cyclone. However, investigation of solids flow characteristics inside the cyclone is often impeded by the nature of the process due to slurry opaqueness and solid metal wall vessels. In this work, a dual-plane high speed Electrical resistance tomography (ERT) is used to measure hydrocyclone internal flow dynamics in situ. Experiments are carried out in 3 inch hydrocyclone for feed solid concentrations varying in the range of 0-50%. ERT data analysis through the optimized FEM mesh size and reconstruction algorithms on air-core and solid concentration tomograms is assessed. Results are presented in terms of the air-core diameter and solids volume fraction contours using Maxwell’s equation for various hydrocyclone operational parameters. It is confirmed by ERT that the air core occupied area and wall solids conductivity levels decreases with increasing the feed solids concentration. Algebraic slip mixture based multi-phase computational fluid dynamics (CFD) model is used to predict the air-core size and the solid concentrations in the hydrocyclone. Validation of air-core size and mean solid volume fractions by ERT measurements with the CFD simulations is attempted.Keywords: air-core, electrical resistance tomography, hydrocyclone, multi-phase CFD
Procedia PDF Downloads 38318374 Utilizing Computational Fluid Dynamics in the Analysis of Natural Ventilation in Buildings
Authors: A. W. J. Wong, I. H. Ibrahim
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Increasing urbanisation has driven building designers to incorporate natural ventilation in the designs of sustainable buildings. This project utilises Computational Fluid Dynamics (CFD) to investigate the natural ventilation of an academic building, SIT@SP, using an assessment criterion based on daily mean temperature and mean velocity. The areas of interest are the pedestrian level of first and fourth levels of the building. A reference case recommended by the Architectural Institute of Japan was used to validate the simulation model. The validated simulation model was then used for coupled simulations on SIT@SP and neighbouring geometries, under two wind speeds. Both steady and transient simulations were used to identify differences in results. Steady and transient results are agreeable with the transient simulation identifying peak velocities during flow development. Under a lower wind speed, the first level was sufficiently ventilated while the fourth level was not. The first level has excessive wind velocities in the higher wind speed and the fourth level was adequately ventilated. Fourth level flow velocity was consistently lower than those of the first level. This is attributed to either simulation model error or poor building design. SIT@SP is concluded to have a sufficiently ventilated first level and insufficiently ventilated fourth level. Future works for this project extend to modifying the urban geometry, simulation model improvements, evaluation using other assessment metrics and extending the area of interest to the entire building.Keywords: buildings, CFD Simulations, natural ventilation, urban airflow
Procedia PDF Downloads 22418373 Comparing the SALT and START Triage System in Disaster and Mass Casualty Incidents: A Systematic Review
Authors: Hendri Purwadi, Christine McCloud
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Triage is a complex decision-making process that aims to categorize a victim’s level of acuity and the need for medical assistance. Two common triage systems have been widely used in Mass Casualty Incidents (MCIs) and disaster situation are START (Simple triage algorithm and rapid treatment) and SALT (sort, asses, lifesaving, intervention, and treatment/transport). There is currently controversy regarding the effectiveness of SALT over START triage system. This systematic review aims to investigate and compare the effectiveness between SALT and START triage system in disaster and MCIs setting. Literatures were searched via systematic search strategy from 2009 until 2019 in PubMed, Cochrane Library, CINAHL, Scopus, Science direct, Medlib, ProQuest. This review included simulated-based and medical record -based studies investigating the accuracy and applicability of SALT and START triage systems of adult and children population during MCIs and disaster. All type of studies were included. Joana Briggs institute critical appraisal tools were used to assess the quality of reviewed studies. As a result, 1450 articles identified in the search, 10 articles were included. Four themes were identified by review, they were accuracy, under-triage, over-triage and time to triage per individual victim. The START triage system has a wide range and inconsistent level of accuracy compared to SALT triage system (44% to 94. 2% of START compared to 70% to 83% of SALT). The under-triage error of START triage system ranged from 2.73% to 20%, slightly lower than SALT triage system (7.6 to 23.3%). The over-triage error of START triage system was slightly greater than SALT triage system (START ranged from 2% to 53% compared to 2% to 22% of SALT). The time for applying START triage system was faster than SALT triage system (START was 70-72.18 seconds compared to 78 second of SALT). Consequently; The START triage system has lower level of under-triage error and faster than SALT triage system in classifying victims of MCIs and disaster whereas SALT triage system is known slightly more accurate and lower level of over-triage. However, the magnitude of these differences is relatively small, and therefore the effect on the patient outcomes is not significance. Hence, regardless of the triage error, either START or SALT triage system is equally effective to triage victims of disaster and MCIs.Keywords: disaster, effectiveness, mass casualty incidents, START triage system, SALT triage system
Procedia PDF Downloads 13618372 Intelligent System of the Grinding Robot for Spiral Welded Pipe
Authors: Getachew Demeissie Ayalew, Yongtao Sun, Yang Yang
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The spiral welded pipe manufacturing industry requires strict production standards for automated grinders for welding seams. However, traditional grinding machines in this sector are insufficient due to a lack of quality control protocols and inconsistent performance. This research aims to improve the quality of spiral welded pipes by developing intelligent automated abrasive belt grinding equipment. The system has equipped with six degrees of freedom (6 DOF) KUKA KR360 industrial robots, enabling concurrent grinding operations on both internal and external welds. The grinding robot control system is designed with a PLC, and a human-machine interface (HMI) system is employed for operations. The system includes an electric speed controller, data connection card, DC driver, analog amplifier, and HMI for input data. This control system enables the grinding of spiral welded pipe. It ensures consistent production quality and cost-effectiveness by reducing the product life cycle and minimizing risks in the working environment.Keywords: Intelligent Systems, Spiral Welded Pipe, Grinding, Industrial Robot, End-Effector, PLC Controller System, 3D Laser Sensor, HMI.
Procedia PDF Downloads 30418371 A Robust Model Predictive Control for a Photovoltaic Pumping System Subject to Actuator Saturation Nonlinearity and Parameter Uncertainties: A Linear Matrix Inequality Approach
Authors: Sofiane Bououden, Ilyes Boulkaibet
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In this paper, a robust model predictive controller (RMPC) for uncertain nonlinear system under actuator saturation is designed to control a DC-DC buck converter in PV pumping application, where this system is subject to actuator saturation and parameter uncertainties. The considered nonlinear system contains a linear constant part perturbed by an additive state-dependent nonlinear term. Based on the saturating actuator property, an appropriate linear feedback control law is constructed and used to minimize an infinite horizon cost function within the framework of linear matrix inequalities. The proposed approach has successfully provided a solution to the optimization problem that can stabilize the nonlinear plants. Furthermore, sufficient conditions for the existence of the proposed controller guarantee the robust stability of the system in the presence of polytypic uncertainties. In addition, the simulation results have demonstrated the efficiency of the proposed control scheme.Keywords: PV pumping system, DC-DC buck converter, robust model predictive controller, nonlinear system, actuator saturation, linear matrix inequality
Procedia PDF Downloads 18318370 A Study on Solutions to Connect Distribution Power Grid up to Renewable Energy Sources at KEPCO
Authors: Seung Yoon Hyun, Hyeong Seung An, Myeong Ho Choi, Sung Hwan Bae, Yu Jong Sim
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In 2015, the southern part of the Korean Peninsula has 8.6 million poles, 1.25 million km power lines, and 2 million transformers, etc. It is the massive amount of distribution equipments which could cover a round-trip distance from the earth to the moon and 11 turns around the earth. These distribution equipments are spread out like capillaries and supplying power to every corner of the Korean Peninsula. In order to manage these huge power facility efficiently, KEPCO use DAS (Distribution Automation System) to operate distribution power system since 1997. DAS is integrated system that enables to remotely supervise and control breakers and switches on distribution network. Using DAS, we can reduce outage time and power loss. KEPCO has about 160,000 switches, 50%(about 80,000) of switches are automated, and 41 distribution center monitoring&control these switches 24-hour 365 days to get the best efficiency of distribution networks. However, the rapid increasing renewable energy sources become the problem in the efficient operation of distributed power system. (currently 2,400 MW, 75,000 generators operate in distribution power system). In this paper, it suggests the way to interconnect between renewable energy source and distribution power system.Keywords: distribution, renewable, connect, DAS (Distribution Automation System)
Procedia PDF Downloads 62918369 Characterisation of Wind-Driven Ventilation in Complex Terrain Conditions
Authors: Daniel Micallef, Damien Bounaudet, Robert N. Farrugia, Simon P. Borg, Vincent Buhagiar, Tonio Sant
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The physical effects of upstream flow obstructions such as vegetation on cross-ventilation phenomena of a building are important for issues such as indoor thermal comfort. Modelling such effects in Computational Fluid Dynamics simulations may also be challenging. The aim of this work is to establish the cross-ventilation jet behaviour in such complex terrain conditions as well as to provide guidelines on the implementation of CFD numerical simulations in order to model complex terrain features such as vegetation in an efficient manner. The methodology consists of onsite measurements on a test cell coupled with numerical simulations. It was found that the cross-ventilation flow is highly turbulent despite the very low velocities encountered internally within the test cells. While no direct measurement of the jet direction was made, the measurements indicate that flow tends to be reversed from the leeward to the windward side. Modelling such a phenomenon proves challenging and is strongly influenced by how vegetation is modelled. A solid vegetation tends to predict better the direction and magnitude of the flow than a porous vegetation approach. A simplified terrain model was also shown to provide good comparisons with observation. The findings have important implications on the study of cross-ventilation in complex terrain conditions since the flow direction does not remain trivial, as with the traditional isolated building case.Keywords: complex terrain, cross-ventilation, wind driven ventilation, wind resource, computational fluid dynamics, CFD
Procedia PDF Downloads 39818368 Gimbal Structure for the Design of 3D Flywheel System
Authors: Cheng-En Tsai, Chung-Chun Hsiao, Fu-Yuan Chang, Liang-Lun Lan, Jia-Ying Tu
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New design of three dimensional (3D) flywheel system based on gimbal and gyro mechanics is proposed. The 3D flywheel device utilizes the rotational motion of three spherical shells and the conservation of angular momentum to achieve planar locomotion. Actuators mounted to the ring-shape frames are installed within the system to drive the spherical shells to rotate, for the purpose of steering and stabilization. Similar to the design of 2D flywheel system, it is expected that the spherical shells may function like a “flyball” to store and supply mechanical energy; additionally, in comparison with typical single-wheel and spherical robots, the 3D flywheel can be used for developing omnidirectional robotic systems with better mobility. The Lagrangian method is applied to derive the equation of motion of the 3D flywheel system, and simulation studies are presented to verify the proposed design.Keywords: Gimbal, spherical robot, gyroscope, Lagrangian formulation, flyball
Procedia PDF Downloads 63118367 Helicopter Exhaust Gases Cooler in Terms of Computational Fluid Dynamics (CFD) Analysis
Authors: Mateusz Paszko, Ksenia Siadkowska
Abstract:
Due to the low-altitude and relatively low-speed flight, helicopters are easy targets for actual combat assets e.g. infrared-guided missiles. Current techniques aim to increase the combat effectiveness of the military helicopters. Protection of the helicopter in flight from early detection, tracking and finally destruction can be realized in many ways. One of them is cooling hot exhaust gasses, emitting from the engines to the atmosphere in special heat exchangers. Nowadays, this process is realized in ejective coolers, where strong heat and momentum exchange between hot exhaust gases and cold air ejected from atmosphere takes place. Flow effects of air, exhaust gases; mixture of those two and the heat transfer between cold air and hot exhaust gases are given by differential equations of: Mass transportation–flow continuity, ejection of cold air through expanding exhaust gasses, conservation of momentum, energy and physical relationship equations. Calculation of those processes in ejective cooler by means of classic mathematical analysis is extremely hard or even impossible. Because of this, it is necessary to apply the numeric approach with modern, numeric computer programs. The paper discussed the general usability of the Computational Fluid Dynamics (CFD) in a process of projecting the ejective exhaust gases cooler cooperating with helicopter turbine engine. In this work, the CFD calculations have been performed for ejective-based cooler cooperating with the PA W3 helicopter’s engines.Keywords: aviation, CFD analysis, ejective-cooler, helicopter techniques
Procedia PDF Downloads 337