Search results for: modeling technique
5561 Contemplating Charge Transport by Modeling of DNA Nucleobases Based Nano Structures
Authors: Rajan Vohra, Ravinder Singh Sawhney, Kunwar Partap Singh
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Electrical charge transport through two basic strands thymine and adenine of DNA have been investigated and analyzed using the jellium model approach. The FFT-2D computations have been performed for semi-empirical Extended Huckel Theory using atomistic tool kit to contemplate the charge transport metrics like current and conductance. The envisaged data is further evaluated in terms of transmission spectrum, HOMO-LUMO Gap and number of electrons. We have scrutinized the behavior of the devices in the range of -2V to 2V for a step size of 0.2V. We observe that both thymine and adenine can act as molecular devices when sandwiched between two gold probes. A prominent observation is a drop in HLGs of adenine and thymine when working as a device as compared to their intrinsic values and this is comparative more visible in case of adenine. The current in the thymine based device exhibit linear increase with voltage in spite of having low conductance. Further, the broader transmission peaks represent the strong coupling of electrodes to the scattering molecule (thymine). Moreover, the observed current in case of thymine is almost 3-4 times than that of observed for adenine. The NDR effect has been perceived in case of adenine based device for higher bias voltages and can be utilized in various future electronics applications.Keywords: adenine, DNA, extended Huckel, thymine, transmission spectra
Procedia PDF Downloads 1585560 Grading of Emulsified Agarwood Oil Using Gel Electrophoresis Technique
Authors: Y. T. Boon, M. N. Naim, R. Zakaria, N. F. Abu Bakar, N. Ahmad, I. W. Lenggoro
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In this study, encapsulation of agarwood oil with non-ionic surfactant, Tween 80 was prepared at critical micelle concentration of 0.0167 % v/v to produce the most stable nano-emulsion in aqueous. The encapsulation has minimized the bioactive compounds degradation in various pH conditions thus prolong their shelf life and maintained its initial oil grade. The oil grading of the prepared samples were conducted using the gel electrophoresis instead of using common analytical industrial grading such as gas chromatography- mass spectrometry (GC- MS). The grading method was chosen due to their unique zeta potential value after the encapsulation process. This paper demonstrates the feasibility of applying the electrophoresis principles to separate the encapsulated agarwood oil or grading of the emulsified agarwood oil. The results indicated that the grading process are potential to be further investigate based on their droplet size and zeta potential value at various pH condition when the droplet were migrate through polyacrylamide gel.Keywords: electrophoretic mobility, essential oil, nanoemulsion, polyacrylamide gel electrophoresis, tween 80, zeta potential
Procedia PDF Downloads 3825559 An Enhanced Particle Swarm Optimization Algorithm for Multiobjective Problems
Authors: Houda Abadlia, Nadia Smairi, Khaled Ghedira
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Multiobjective Particle Swarm Optimization (MOPSO) has shown an effective performance for solving test functions and real-world optimization problems. However, this method has a premature convergence problem, which may lead to lack of diversity. In order to improve its performance, this paper presents a hybrid approach which embedded the MOPSO into the island model and integrated a local search technique, Variable Neighborhood Search, to enhance the diversity into the swarm. Experiments on two series of test functions have shown the effectiveness of the proposed approach. A comparison with other evolutionary algorithms shows that the proposed approach presented a good performance in solving multiobjective optimization problems.Keywords: particle swarm optimization, migration, variable neighborhood search, multiobjective optimization
Procedia PDF Downloads 1705558 TiN/TiO2 Nanostructure Coating on Glass Substrate
Authors: F. Dabir, R. Sarraf-Mamoory, N. Riahi-Noori
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In this work, a nanostructured TiO2 layer was coated onto a FTO-less glass substrate using screen printing technique for back contact DSSC application. Then, titanium nitride thin film was applied on TiO2 layer by plasma assisted chemical vapor deposition (PACVD) as charge collector layer. The microstructure of prepared TiO2 layer was characterized by SEM. The sheet resistance, microstructure and elemental composition of titanium nitride thin films were analysed by four point probe, SEM, and EDS, respectively. TiO2 layer had porous nanostructure. The EDS analysis of TiN thin film showed presence of chlorine impurity. Sheet resistance of TiN thin film was 30 Ω/sq. With respect to the results, PACVD TiN can be a good candidate as a charge collector layer in back contacts DSSC.Keywords: TiO2, TiN, charge collector, DSSC
Procedia PDF Downloads 4655557 Development of Geo-computational Model for Analysis of Lassa Fever Dynamics and Lassa Fever Outbreak Prediction
Authors: Adekunle Taiwo Adenike, I. K. Ogundoyin
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Lassa fever is a neglected tropical virus that has become a significant public health issue in Nigeria, with the country having the greatest burden in Africa. This paper presents a Geo-Computational Model for Analysis and Prediction of Lassa Fever Dynamics and Outbreaks in Nigeria. The model investigates the dynamics of the virus with respect to environmental factors and human populations. It confirms the role of the rodent host in virus transmission and identifies how climate and human population are affected. The proposed methodology is carried out on a Linux operating system using the OSGeoLive virtual machine for geographical computing, which serves as a base for spatial ecology computing. The model design uses Unified Modeling Language (UML), and the performance evaluation uses machine learning algorithms such as random forest, fuzzy logic, and neural networks. The study aims to contribute to the control of Lassa fever, which is achievable through the combined efforts of public health professionals and geocomputational and machine learning tools. The research findings will potentially be more readily accepted and utilized by decision-makers for the attainment of Lassa fever elimination.Keywords: geo-computational model, lassa fever dynamics, lassa fever, outbreak prediction, nigeria
Procedia PDF Downloads 965556 Optimal Design of InGaP/GaAs Heterojonction Solar Cell
Authors: Djaafar F., Hadri B., Bachir G.
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We studied mainly the influence of temperature, thickness, molar fraction and the doping of the various layers (emitter, base, BSF and window) on the performances of a photovoltaic solar cell. In a first stage, we optimized the performances of the InGaP/GaAs dual-junction solar cell while varying its operation temperature from 275°K to 375 °K with an increment of 25°C using a virtual wafer fabrication TCAD Silvaco. The optimization at 300°K led to the following result Icc =14.22 mA/cm2, Voc =2.42V, FF =91.32 %, η = 22.76 % which is close with those found in the literature. In a second stage ,we have varied the molar fraction of different layers as well their thickness and the doping of both emitters and bases and we have registered the result of each variation until obtaining an optimal efficiency of the proposed solar cell at 300°K which was of Icc=14.35mA/cm2,Voc=2.47V,FF=91.34,and η =23.33% for In(1-x)Ga(x)P molar fraction( x=0.5).The elimination of a layer BSF on the back face of our cell, enabled us to make a remarkable improvement of the short-circuit current (Icc=14.70 mA/cm2) and a decrease in open circuit voltage Voc and output η which reached 1.46V and 11.97% respectively. Therefore, we could determine the critical parameters of the cell and optimize its various technological parameters to obtain the best performance for a dual junction solar cell. This work opens the way with new prospects in the field of the photovoltaic one. Such structures will thus simplify the manufacturing processes of the cells; will thus reduce the costs while producing high outputs of photovoltaic conversion.Keywords: modeling, simulation, multijunction, optimization, silvaco ATLAS
Procedia PDF Downloads 6245555 Study of Sub-Surface Flow in an Unconfined Carbonate Aquifer in a Tropical Karst Area in Indonesia: A Modeling Approach Using Finite Difference Groundwater Model
Authors: Dua K. S. Y. Klaas, Monzur A. Imteaz, Ika Sudiayem, Elkan M. E. Klaas, Eldav C. M. Klaas
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Due to its porous nature, karst terrains – geomorphologically developed from dissolved formations, is vulnerable to water shortage and deteriorated water quality. Therefore, a solid comprehension on sub-surface flow of karst landscape is essential to assess the long-term availability of groundwater resources. In this paper, a single-continuum model using a finite difference model, MODLFOW, was constructed to represent an unconfined carbonate aquifer in a tropical karst island of Rote in Indonesia. The model, spatially discretized in 20 x 20 m grid cells, was calibrated and validated using available groundwater level and atmospheric variables. In the calibration and validation steps, Parameter Estimation (PEST) and geostatistical pilot point methods were employed to estimate hydraulic conductivity and specific yield values. The results show that the model is able to represent the sub-surface flow indicated by good model performances both in calibration and validation steps. The final model can be used as a robust representation of the system for future study on climate and land use scenarios.Keywords: carbonate aquifer, karst, sub-surface flow, groundwater model
Procedia PDF Downloads 1525554 Interval Type-2 Fuzzy Vibration Control of an ERF Embedded Smart Structure
Authors: Chih-Jer Lin, Chun-Ying Lee, Ying Liu, Chiang-Ho Cheng
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The main objective of this article is to present the semi-active vibration control using an electro-rheological fluid embedded sandwich structure for a cantilever beam. ER fluid is a smart material, which cause the suspended particles polarize and connect each other to form chain. The stiffness and damping coefficients of the ER fluid can be changed in 10 micro seconds; therefore, ERF is suitable to become the material embedded in the tunable vibration absorber to become a smart absorber. For the ERF smart material embedded structure, the fuzzy control law depends on the experimental expert database and the proposed self-tuning strategy. The electric field is controlled by a CRIO embedded system to implement the real application. This study investigates the different performances using the Type-1 fuzzy and interval Type-2 fuzzy controllers. The Interval type-2 fuzzy control is used to improve the modeling uncertainties for this ERF embedded shock absorber. The self-tuning vibration controllers using Type-1 and Interval Type-2 fuzzy law are implemented to the shock absorber system. Based on the resulting performance, Internal Type-2 fuzzy is better than the traditional Type-1 fuzzy control for this vibration control system.Keywords: electro-rheological fluid, semi-active vibration control, shock absorber, type 2 fuzzy control
Procedia PDF Downloads 4485553 Transient Hygrothermoelastic Behavior in an Infinite Annular Cylinder with Internal Heat Generation by Linear Dependence Theory of Coupled Heat and Moisture
Authors: Tasneem Firdous Islam, G. D. Kedar
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The aim of this paper is to study the effect of internal heat generation in a transient infinitely long annular cylinder subjected to hygrothermal loadings. The linear dependence theory of moisture and temperature is derived based on Dufour and Soret effect. The meticulous solutions of temperature, moisture, and thermal stresses are procured by using the Hankel transform technique. The influence of the internal heat source on the radial aspect is examined for coupled and uncoupled cases. In the present study, the composite material T300/5208 is considered, and the coupled and uncoupled cases are analyzed. The results obtained are computed numerically and illustrated graphically.Keywords: temperature, moisture, hygrothermoelasticity, internal heat generation, annular cylinder
Procedia PDF Downloads 1165552 Production of Hard Nickel Particle Reinforced Ti6Al4V Matrix Composites by Hot Pressing
Authors: Ridvan Yamanoglu
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In the current study, titanium based composites reinforced by hard nickel alloy particles were produced. Powder metallurgical hot pressing technique was used for the fabrication of composite materials. The composites containing different ratio of hard nickel particles were sintered at 900 oC for 15 and 30 minutes under 50 MPa pressure. All titanium based composites were obtained under a vacuum atmosphere of 10-4 mbar to prevent of oxidation of titanium due to its high reactivity to oxygen. The microstructural characterization of the composite samples was carried out by optical and scanning electron microscopy. The mechanical properties of the samples were determined by means of hardness and wear tests. The results showed that when the nickel particle content increased the mechanical properties of the composites enhanced. The results are discussed in detail and optimum nickel particle content were determined.Keywords: titanium, composite, nickel, hot pressing
Procedia PDF Downloads 1745551 Operator Efficiency Study for Assembly Line Optimization at Semiconductor Assembly and Test
Authors: Rohana Abdullah, Md Nizam Abd Rahman, Seri Rahayu Kamat
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Operator efficiency aspect is gaining importance in ensuring optimized usage of resources especially in the semi-automated manufacturing environment. This paper addresses a case study done to solve operator efficiency and line balancing issue at a semiconductor assembly and test manufacturing. A Man-to-Machine (M2M) work study technique is used to study operator current utilization and determine the optimum allocation of the operators to the machines. Critical factors such as operator activity, activity frequency and operator competency level are considered to gain insight on the parameters that affects the operator utilization. Equipment standard time and overall equipment efficiency (OEE) information are also gathered and analyzed to achieve a balanced and optimized production.Keywords: operator efficiency, optimized production, line balancing, industrial and manufacturing engineering
Procedia PDF Downloads 7305550 Investigation Edge Coverage of Automotive Electrocoats Filled by Nano Silica Particles
Authors: Marzieh Bakhtiary Noodeh, Mahla Zabet
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Attempts have been carried out to enhance the anticorrosion properties as well as edge coverage of an automotive electrocoating using the nano silica particles. To this end, the automotive electrocoating was reinforced with the nano silica particles at various weight fractions. The electrocoats were applied on the surface of punched edge followed by curing at 160⁰C for 20 min. The effects of nano silica particles on the rheological properties, influencing edge coverage were studied by a RMS (Rheometric Mechanical Spectrometer) technique. The anticorrosion properties were studied by a salt-spray test. The results obtained revealed that nano silica particles can significantly enhance the edge coverage by increasing minimum melt viscosity of electrocoats. It was shown that using 4 wt% nano silica particles, both anticorrosion properties and edge coverage of the electrocoats were significantly improved.Keywords: nano silica, electrocoat, edge coverage, anticorrosion
Procedia PDF Downloads 3085549 Models of State Organization and Influence over Collective Identity and Nationalism in Spain
Authors: Muñoz-Sanchez, Victor Manuel, Perez-Flores, Antonio Manuel
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The main objective of this paper is to establish the relationship between models of state organization and the various types of collective identity expressed by the Spanish. The question of nationalism and identity ascription in Spain has always been a topic of special importance due to the presence in that country of territories where the population emits very different opinions of nationalist sentiment than the rest of Spain. The current situation of sovereignty challenge of Catalonia to the central government exemplifies the importance of the subject matter. In order to analyze this process of interrelation, we use a secondary data mining by applying the multiple correspondence analysis technique (MCA). As a main result a typology of four types of expression of collective identity based on models of State organization are shown, which are connected with the party position on this issue.Keywords: models of organization of the state, nationalism, collective identity, Spain, political parties
Procedia PDF Downloads 4455548 Population Size Estimation Based on the GPD
Authors: O. Anan, D. Böhning, A. Maruotti
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The purpose of the study is to estimate the elusive target population size under a truncated count model that accounts for heterogeneity. The purposed estimator is based on the generalized Poisson distribution (GPD), which extends the Poisson distribution by adding a dispersion parameter. Thus, it becomes an useful model for capture-recapture data where concurrent events are not homogeneous. In addition, it can account for over-dispersion and under-dispersion. The ratios of neighboring frequency counts are used as a tool for investigating the validity of whether generalized Poisson or Poisson distribution. Since capture-recapture approaches do not provide the zero counts, the estimated parameters can be achieved by modifying the EM-algorithm technique for the zero-truncated generalized Poisson distribution. The properties and the comparative performance of proposed estimator were investigated through simulation studies. Furthermore, some empirical examples are represented insights on the behavior of the estimators.Keywords: capture, recapture methods, ratio plot, heterogeneous population, zero-truncated count
Procedia PDF Downloads 4365547 Digital Reconstruction of the Cultural Landscape: Chengde Summer Resort as a Case Study
Authors: Jingsen Lian, Steffen Nijhuis, Gregory Bracken, Kai Lan
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This study explores the digital reconstruction of the Chengde Mountain Resort (CMR), a UNESCO World Heritage Site recognized for its cultural landscape significance. Using mixed methods, the research combines spatial, textual, and graphical data to reconstruct the historical evolution of CMR's landscape across four phases from 1704 to the present. Data acquisition includes 3D point clouds, historical maps, traditional paintings, poetry, land-use records, academic papers, engineering drawings, and old photographs. Interdisciplinary techniques such as georectification, 3D modeling, and textual analysis were employed to integrate these diverse datasets into a cohesive Web-GIS platform. The reconstructed data illustrates dynamic landscape changes, reflecting shifting cultural and ecological priorities. The Web-GIS platform facilitates data visualization, querying, and customization, serving multiple stakeholders, including researchers, government planners, and local communities. This study underscores the value of digital tools in cultural heritage preservation, offering a model for adaptive and participatory management of historical sites while promoting open access and stakeholder engagement.Keywords: landscape mapping, cultural landscape, heritage, case study, mixed methods
Procedia PDF Downloads 65546 Numerical Investigation of Hot Oil Velocity Effect on Force Heat Convection and Impact of Wind Velocity on Convection Heat Transfer in Receiver Tube of Parabolic Trough Collector System
Authors: O. Afshar
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A solar receiver is designed for operation under extremely uneven heat flux distribution, cyclic weather, and cloud transient cycle conditions, which can include large thermal stress and even receiver failure. In this study, the effect of different oil velocity on convection coefficient factor and impact of wind velocity on local Nusselt number by Finite Volume Method will be analyzed. This study is organized to give an overview of the numerical modeling using a MATLAB software, as an accurate, time efficient and economical way of analyzing the heat transfer trends over stationary receiver tube for different Reynolds number. The results reveal when oil velocity is below 0.33m/s, the value of convection coefficient is negligible at low temperature. The numerical graphs indicate that when oil velocity increases up to 1.2 m/s, heat convection coefficient increases significantly. In fact, a reduction in oil velocity causes a reduction in heat conduction through the glass envelope. In addition, the different local Nusselt number is reduced when the wind blows toward the concave side of the collector and it has a significant effect on heat losses reduction through the glass envelope.Keywords: receiver tube, heat convection, heat conduction, Nusselt number
Procedia PDF Downloads 3575545 Removal of Hexavalent Chromium from Aqueous Solutions by Biosorption Using Macadamia Nutshells: Effect of Different Treatment Methods
Authors: Vusumzi E. Pakade, Themba D. Ntuli, Augustine E. Ofomaja
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Macadamia nutshell biosorbents treated in three different methods (raw Macadamia nutshell powder (RMN), acid-treated Macadamia nutshell (ATMN) and base-treated Macadamia nutshell (BTMN)) were investigated for the adsorption of Cr(VI) from aqueous solutions. Fourier transform infrared spectroscopy (FT-IR) spectra of free and Cr(VI)-loaded sorbents as well as thermogravimetric analysis (TGA) revealed that the acid and base treatments modified the surface properties of the sorbents. The optimum conditions for the adsorption of Cr(VI) by sorbents were pH 2, contact time 10 h, adsorbent dosage 0.2 g L-1, and concentration 100 mg L-1. The different treatment methods altered the surface characteristics of the sorbents and produced different maximum binding capacities of 42.5, 40.6 and 37.5 mg g-1 for RMN, ATMN and BTMN, respectively. The data was fitted into the Langmuir, Freundlich, Redlich-Peterson and Sips isotherms. No single model could clearly explain the data perhaps due to the complexity of process taking place. The kinetic modeling results showed that the process of Cr(VI) biosorption with Macadamia sorbents was better described by a process of chemical sorption in pseudo-second order. These results showed that the three treatment methods yielded different surface properties which then influenced adsorption of Cr(VI) differently.Keywords: biosorption, chromium(VI), isotherms, Macadamia, reduction, treatment
Procedia PDF Downloads 2685544 Simulation Studies of Solid-Particle and Liquid-Drop Erosion of NiAl Alloy
Authors: Rong Liu, Kuiying Chen, Ju Chen, Jingrong Zhao, Ming Liang
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This article presents modeling studies of NiAl alloy under solid-particle erosion and liquid-drop erosion. In the solid particle erosion simulation, attention is paid to the oxide scale thickness variation on the alloy in high-temperature erosion environments. The erosion damage is assumed to be deformation wear and cutting wear mechanisms, incorporating the influence of the oxide scale on the eroded surface; thus the instantaneous oxide thickness is the result of synergetic effect of erosion and oxidation. For liquid-drop erosion, special interest is in investigating the effects of drop velocity and drop size on the damage of the target surface. The models of impact stress wave, mean depth of penetration, and maximum depth of erosion rate (Max DER) are employed to develop various maps for NiAl alloy, including target thickness vs. drop size (diameter), rate of mean depth of penetration (MDRP) vs. drop impact velocity, and damage threshold velocity (DTV) vs. drop size.Keywords: liquid-drop erosion, NiAl alloy, oxide scale thickness, solid-particle erosion
Procedia PDF Downloads 5785543 Application of Nanoparticles in Biomedical and MRI
Authors: Raziyeh Mohammadi
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At present, nanoparticles are used for various biomedical applications where they facilitate laboratory diagnostics and therapeutics. The performance of nanoparticles for biomedical applications is often assessed by their narrow size distribution, suitable magnetic saturation, and low toxicity effects. Superparamagnetic iron oxide nanoparticles have received great attention due to their applications as contrast agents for magnetic resonance imaging (MRI. (Processes in the tissue where the blood brain barrier is intact in this way shielded from the contact to this conventional contrast agent and will only reveal changes in the tissue if it involves an alteration in the vasculature. This technique is very useful for detecting tumors and can even be used for detecting metabolic functional alterations in the brain, such as epileptic activity.SPIONs have found application in Magnetic Resonance Imaging (MRI) and magnetic hyperthermia. Unlike bulk iron, SPIONs do not have remnant magnetization in the absence of the external magnetic field; therefore, a precise remote control over their action is possible.Keywords: nanoparticles, MRI, biomedical, iron oxide, spions
Procedia PDF Downloads 2175542 BART Matching Method: Using Bayesian Additive Regression Tree for Data Matching
Authors: Gianna Zou
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Propensity score matching (PSM), introduced by Paul R. Rosenbaum and Donald Rubin in 1983, is a popular statistical matching technique which tries to estimate the treatment effects by taking into account covariates that could impact the efficacy of study medication in clinical trials. PSM can be used to reduce the bias due to confounding variables. However, PSM assumes that the response values are normally distributed. In some cases, this assumption may not be held. In this paper, a machine learning method - Bayesian Additive Regression Tree (BART), is used as a more robust method of matching. BART can work well when models are misspecified since it can be used to model heterogeneous treatment effects. Moreover, it has the capability to handle non-linear main effects and multiway interactions. In this research, a BART Matching Method (BMM) is proposed to provide a more reliable matching method over PSM. By comparing the analysis results from PSM and BMM, BMM can perform well and has better prediction capability when the response values are not normally distributed.Keywords: BART, Bayesian, matching, regression
Procedia PDF Downloads 1495541 Building Safety Through Real-time Design Fire Protection Systems
Authors: Mohsin Ali Shaikh, Song Weiguo, Muhammad Kashan Surahio, Usman Shahid, Rehmat Karim
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When the area of a structure that is threatened by a disaster affects personal safety, the effectiveness of disaster prevention, evacuation, and rescue operations can be summarized by three assessment indicators: personal safety, property preservation, and attribution of responsibility. These indicators are applicable regardless of the disaster that affects the building. People need to get out of the hazardous area and to a safe place as soon as possible because there's no other way to respond. The results of the tragedy are thus closely related to how quickly people are advised to evacuate and how quickly they are rescued. This study considers present fire prevention systems to address catastrophes and improve building safety. It proposes the methods of Prevention Level for Deployment in Advance and Spatial Transformation by Human-Machine Collaboration. We present and prototype a real-time fire protection system architecture for building disaster prevention, evacuation, and rescue operations. The design encourages the use of simulations to check the efficacy of evacuation, rescue, and disaster prevention procedures throughout the planning and design phase of the structure.Keywords: prevention level, building information modeling, quality management system, simulated reality
Procedia PDF Downloads 705540 IACOP - Route Optimization in Wireless Networks Using Improved Ant Colony Optimization Protocol
Authors: S. Vasundra, D. Venkatesh
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Wireless networks have gone through an extraordinary growth in the past few years, and will keep on playing a crucial role in future data communication. The present wireless networks aim to make communication possible anywhere and anytime. With the converging of mobile and wireless communications with Internet services, the boundary between mobile personal telecommunications and wireless computer networks is disappearing. Wireless networks of the next generation need the support of all the advances on new architectures, standards, and protocols. Since an ad hoc network may consist of a large number of mobile hosts, this imposes a significant challenge on the design of an effective and efficient routing protocol that can work well in an environment with frequent topological changes. This paper proposes improved ant colony optimization (IACO) technique. It also maintains load balancing in wireless networks. The simulation results show that the proposed IACO performs better than existing routing techniques.Keywords: wireless networks, ant colony optimization, load balancing, architecture
Procedia PDF Downloads 4255539 Reduction of Aerodynamic Drag Using Vortex Generators
Authors: Siddharth Ojha, Varun Dua
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Classified as one of the most important reasons of aerodynamic drag in the sedan automobiles is the fluid flow separation near the vehicle’s rear end. To retard the separation of flow, bump-shaped vortex generators are being tested for its implementation to the roof end of a sedan vehicle. Frequently used in the aircrafts to prevent the separation of fluid flow, vortex generators themselves produce drag, but they also substantially reduce drag by preventing flow separation at the downstream. The net effects of vortex generators can be calculated by summing the positive and negative impacts and effects. Since this effect depends on dimensions and geometry of vortex generators, those present on the vehicle roof are optimized for maximum efficiency and performance. The model was tested through ANSYS CFD analysis and modeling. The model was tested in the wind tunnel for observing it’s properties such as aerodynamic drag and flow separation and a major time lag was gained by employing vortex generators in the scaled model. Major conclusions which were recorded during the analysis were a substantial 24% reduction in the aerodynamic drag and 14% increase in the efficiency of the sedan automobile as the flow separation from the surface is delayed. This paper presents the results of optimization, the effect of vortex generators in the flow field and the mechanism by which these effects occur and are regulated.Keywords: aerodynamics, aerodynamic devices, body, computational fluid dynamics (CFD), flow visualization
Procedia PDF Downloads 2245538 Pushover Analysis of Reinforced Concrete Beam-Column Joint Strengthening with Ultra High Performance Concrete
Authors: Abdulsamee Halahla, Emad Allout
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The purpose of this research is to study the behavior of exterior beam-column joints (BCJs) strengthened with ultra-high performance concrete (UHPC), in terms of the shear strength and maximum displacement using pushover analysis at the tip of the beam. A finite element (F.E) analysis was performed to study three main parameters – the level of the axial load in the column (N), the beam shear reinforcement (Av/s)B, and the effect of using UHPC. The normal concrete at the studied joint region was replaced by UHPC. The model was verified by using experimental results taken from the literature. The results showed that the UHPC contributed to the transference of the plastic hinge from the joint to the beam-column interface. In addition, the strength of the UHPC-strengthened joints was enhanced dramatically from 8% to 38% for the joints subjected to 12.8MPa and zero axial loads, respectively. Moreover, the UHPC contributed in improving the maximum deflection. This improvement amounted to 1% and 176% for the joints subjected to zero and 12.8MPa axial load, respectively.Keywords: ultra high performance concrete, ductility, reinforced concrete joints, finite element modeling, nonlinear behavior; pushover analysis
Procedia PDF Downloads 1385537 A System Dynamics Model for Assessment of Alternative Energy Policy Measures: A Case of Energy Management System as an Energy Efficiency Policy Tool
Authors: Andra Blumberga, Uldis Bariss, Anna Kubule, Dagnija Blumberga
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European Union Energy Efficiency Directive provides a set of binding energy efficiency measures to reach. Each of the member states can use either energy efficiency obligation scheme or alternative policy measures or combination of both. Latvian government has decided to divide savings among obligation scheme (65%) and alternative measures (35%). This decision might lead to significant energy tariff increase hence impact on the national economy. To assess impact of alternative policy measures focusing on energy management scheme based on ISO 50001 and ability to decrease share of obligation scheme a System Dynamics modeling was used. Simulation results show that energy efficiency goal can be met with alternative policy measure to large energy consumers in industrial, tertiary and public sectors by applying the energy tax exemption for implementers of energy management system. A delay in applying alternative policy measures plays very important role in reaching the energy efficiency goal. One year delay in implementation of this policy measure reduces cumulative energy savings from 2016 to 2017 from 5200 GWh to 3000 GWh in 2020.Keywords: system dynamics, energy efficiency, policy measure, energy management system, obligation scheme
Procedia PDF Downloads 2845536 Classification Based on Deep Neural Cellular Automata Model
Authors: Yasser F. Hassan
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Deep learning structure is a branch of machine learning science and greet achievement in research and applications. Cellular neural networks are regarded as array of nonlinear analog processors called cells connected in a way allowing parallel computations. The paper discusses how to use deep learning structure for representing neural cellular automata model. The proposed learning technique in cellular automata model will be examined from structure of deep learning. A deep automata neural cellular system modifies each neuron based on the behavior of the individual and its decision as a result of multi-level deep structure learning. The paper will present the architecture of the model and the results of simulation of approach are given. Results from the implementation enrich deep neural cellular automata system and shed a light on concept formulation of the model and the learning in it.Keywords: cellular automata, neural cellular automata, deep learning, classification
Procedia PDF Downloads 2005535 A Study on the Response of Vacuum Consolidation on Soft Clay in Combination with Prefabricated Vertical Drain (PVD), Embankment and Surcharge Preloading
Authors: Sharmeelee Subramaniam, Muhd Harris Ramli, Fauziah Ahmad
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The application of vacuum pressure to accelerate ground consolidation has been growing significantly in recent years. This ground improvement technique has its advantages, especially in areas where suitable fill is scarce, as it minimizes the surcharge fill height required for the preloading. A study was carried out to examine the response of soft subsoil subjected to vacuum consolidation in combination with embankment loading, surcharge preloading and PVD with two-way drainage. This paper shall describe a procedure to determine the optimum surcharge height and penetration depth of prefabricated vertical drains (PVD) where vacuum consolidation is combined with the use of PVD in soft clay deposits with two-way drainage.Keywords: prefabricated vertical drain, soft soil, surcharge preload, vacuum consolidation
Procedia PDF Downloads 845534 Implementation of the Interlock Protocol to Enhance Security in Unmanned Aerial Vehicles
Authors: Vikram Prabhu, Mohammad Shikh Bahaei
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This paper depicts the implementation of a new infallible technique to protect an Unmanned Aerial Vehicle from cyber-attacks. An Unmanned Aerial Vehicle (UAV) could be vulnerable to cyber-attacks because of jammers or eavesdroppers over the network which pose as a threat to the security of the UAV. In the field of network security, there are quite a few protocols which can be used to establish a secure connection between UAVs and their Operators. In this paper, we discuss how the Interlock Protocol could be implemented to foil the Man-in-the-Middle Attack. In this case, Wireshark has been used as the sniffer (man-in-the-middle). This paper also shows a comparison between the Interlock Protocol and the TCP Protocols using cryptcat and netcat and at the same time highlights why the Interlock Protocol is the most efficient security protocol to prevent eavesdropping over the communication channel.Keywords: interlock protocol, Diffie-Hellman algorithm, unmanned aerial vehicles, control station, man-in-the-middle attack, Wireshark
Procedia PDF Downloads 3055533 Mixed Integer Programing for Multi-Tier Rebate with Discontinuous Cost Function
Authors: Y. Long, L. Liu, K. V. Branin
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One challenge faced by procurement decision-maker during the acquisition process is how to compare similar products from different suppliers and allocate orders among different products or services. This work focuses on allocating orders among multiple suppliers considering rebate. The objective function is to minimize the total acquisition cost including purchasing cost and rebate benefit. Rebate benefit is complex and difficult to estimate at the ordering step. Rebate rules vary for different suppliers and usually change over time. In this work, we developed a system to collect the rebate policies, standardized the rebate policies and developed two-stage optimization models for ordering allocation. Rebate policy with multi-tiers is considered in modeling. The discontinuous cost function of rebate benefit is formulated for different scenarios. A piecewise linear function is used to approximate the discontinuous cost function of rebate benefit. And a Mixed Integer Programing (MIP) model is built for order allocation problem with multi-tier rebate. A case study is presented and it shows that our optimization model can reduce the total acquisition cost by considering rebate rules.Keywords: discontinuous cost function, mixed integer programming, optimization, procurement, rebate
Procedia PDF Downloads 2625532 The Influence of Trait of Personality, Stress and Driver Behavior on Road Accident among Bas Driver in Indonesia
Authors: Fikri, Rozmi Ismail, Fatimah Wati Halim, Sarah Waheeda
Abstract:
The aim of this research is to investigate the influence of personality and driver behavior on road accident among bus driver who have the high risk behavior on road accident in Riau Province. The hypotheses proposed this research is there are has a significant influences of Treat of Personality and Driver Behavior among bus driver in Riau Province Indonesia. Subject participated in this research are 100 bus driver in Riau Province. This study using the purposive random sampling technique and quantitative design. The data is collected using the Big Five Personality questionnaires, Driver Behavior questionnaires and Road Accident Inventory. Research found that there are significant influence of personality and driver behavior on road accident among bus driver in Riau Province Indonesia.Keywords: personality, driver behavior, driver stress, road accident
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