Search results for: hybrid optimization
1951 Numerical Analysis of a Mechanism for the Morphology in the Extrados of an Airfoil
Authors: E. R. Jimenez Barron, M. Castillo Morales, D. F. Ramírez Morales
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The study of the morphology (shape change) in wings leads to the optimization of aerodynamic characteristics in an aircraft, so for the development and implementation of a change in the structure and shape of an airfoil, in this case the extrados, helps to increase the aerodynamic performance of an aircraft at different operating velocities, according to the required mission profile. A previous work on morphology is continued where the 'initial' profile is the NACA 4415 and as a new profile 'objective' the FUSION. The objective of this work is the dimensioning of the elements of the mechanism used to achieve the required changes. We consulted the different materials used in the aeronautics industry, as well as new materials in this area that could contribute to the good performance of the mechanism without negatively affecting the aerodynamics. These results allow evaluating the performance of a wing with variable extrados with respect to the defined morphology.Keywords: numerical analysis, mechanisms, morphing airfoil, morphing wings
Procedia PDF Downloads 2371950 Mathematical Modeling for the Break-Even Point Problem in a Non-homogeneous System
Authors: Filipe Cardoso de Oliveira, Lino Marcos da Silva, Ademar Nogueira do Nascimento, Cristiano Hora de Oliveira Fontes
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This article presents a mathematical formulation for the production Break-Even Point problem in a non-homogeneous system. The optimization problem aims to obtain the composition of the best product mix in a non-homogeneous industrial plant, with the lowest cost until the breakeven point is reached. The problem constraints represent real limitations of a generic non-homogeneous industrial plant for n different products. The proposed model is able to solve the equilibrium point problem simultaneously for all products, unlike the existing approaches that propose a resolution in a sequential way, considering each product in isolation and providing a sub-optimal solution to the problem. The results indicate that the product mix found through the proposed model has economical advantages over the traditional approach used.Keywords: branch and bound, break-even point, non-homogeneous production system, integer linear programming, management accounting
Procedia PDF Downloads 2121949 Mental Health Representation in Video Games
Authors: Leonid Rybakovski
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Contemporary media offer a variety of themes for the diverse tastes of their audiences. The Digital games medium was mostly perceived as an instrument of entertainment. But being a part of global trends while constantly pushing the boundaries of storytelling in virtual reality and standing on the edge of technology also brings huge responsibility for game designers around the globe. A very recent emerging topic over the last years was an individual's mental state. In recent years there has been a shift in mental problems representations in commercial game releases such as Hell blade: Senua's Sacrifice and Sea of Solitude. The aim of this study is to research the approach of mental illness representation in media and digital games over the years and to suggest alternatives for putting characters who suffer from mental illness at the forefront of the storyline. This study traces dominant representations of characters with mental illness in digital games, reflecting the major change of the game industry toward inclusiveness. At the same time, the research embraces a hybrid approach to the academic study of digital games and includes the development of a game that follows a post-traumatic young girl, forcing the users to live her life through her eyes. The game prototype was developed as part of the Mdes Game Design and Development program and consisted of academic research and game development practices.Keywords: framing analysis, mental condition, up keying, game mechanics
Procedia PDF Downloads 1741948 A Numerical Study of Seismic Effects on Slope Stability Using Node-Based Smooth Finite Element Method
Authors: H. C. Nguyen
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This contribution considers seismic effects on the stability of slope and footing resting on a slope. The seismic force is simply treated as static inertial force through the values of acceleration factor. All domains are assumed to be plasticity deformations approximated using node-based smoothed finite element method (NS-FEM). The failure mechanism and safety factor were then explored using numerical procedure based on upper bound approach in which optimization problem was formed as second order cone programming (SOCP). The data obtained confirm that upper bound procedure using NS-FEM and SOCP can give stable and rapid convergence results of seismic stability factors.Keywords: upper bound analysis, safety factor, slope stability, footing resting on slope
Procedia PDF Downloads 1181947 Application of Stabilized Polyaniline Microparticles for Better Protective Ability of Zinc Coatings
Authors: N. Boshkova, K. Kamburova, N. Tabakova, N. Boshkov, Ts. Radeva
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Coatings based on polyaniline (PANI) can improve the resistance of steel against corrosion. In this work, the preparation of stable suspensions of colloidal PANI-SiO2 particles, suitable for obtaining of composite anticorrosive coating on steel, is described. Electrokinetic data as a function of pH are presented, showing that the zeta potentials of the PANI-SiO2 particles are governed primarily by the charged groups at the silica oxide surface. Electrosteric stabilization of the PANI-SiO2 particles’ suspension against aggregation is realized at pH>5.5 (EB form of PANI) by adsorption of positively charged polyelectrolyte molecules onto negatively charged PANI-SiO2 particles. The PANI-SiO2 particles are incorporated by electrodeposition into the metal matrix of zinc in order to obtain composite (hybrid) coatings. The latter are aimed to ensure sacrificial protection of steel mainly in aggressive media leading to local corrosion damages. The surface morphology of the composite zinc coatings is investigated with SEM. The influence of PANI-SiO2 particles on the cathodic and anodic processes occurring in the starting electrolyte for obtaining of the coatings is followed with cyclic voltammetry. The electrochemical and corrosion behavior is evaluated with potentiodynamic polarization curves and polarization resistance measurements. The beneficial effect of the stabilized PANI-SiO2 particles for the increased protective ability of the composites is commented and discussed.Keywords: corrosion, polyaniline-silica particles, zinc, protective ability
Procedia PDF Downloads 1751946 Numerical Modeling for Water Engineering and Obstacle Theory
Authors: Mounir Adal, Baalal Azeddine, Afifi Moulay Larbi
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Numerical analysis is a branch of mathematics devoted to the development of iterative matrix calculation techniques. We are searching for operations optimization as objective to calculate and solve systems of equations of order n with time and energy saving for computers that are conducted to calculate and analyze big data by solving matrix equations. Furthermore, this scientific discipline is producing results with a margin of error of approximation called rates. Thus, the results obtained from the numerical analysis techniques that are held on computer software such as MATLAB or Simulink offers a preliminary diagnosis of the situation of the environment or space targets. By this we can offer technical procedures needed for engineering or scientific studies exploitable by engineers for water.Keywords: numerical analysis methods, obstacles solving, engineering, simulation, numerical modeling, iteration, computer, MATLAB, water, underground, velocity
Procedia PDF Downloads 4651945 Motion Estimator Architecture with Optimized Number of Processing Elements for High Efficiency Video Coding
Authors: Seongsoo Lee
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Motion estimation occupies the heaviest computation in HEVC (high efficiency video coding). Many fast algorithms such as TZS (test zone search) have been proposed to reduce the computation. Still the huge computation of the motion estimation is a critical issue in the implementation of HEVC video codec. In this paper, motion estimator architecture with optimized number of PEs (processing element) is presented by exploiting early termination. It also reduces hardware size by exploiting parallel processing. The presented motion estimator architecture has 8 PEs, and it can efficiently perform TZS with very high utilization of PEs.Keywords: motion estimation, test zone search, high efficiency video coding, processing element, optimization
Procedia PDF Downloads 3661944 Elaboration and Characterization of MEH-PPV/PCBM Composite Film Doped with TiO2 Nanoparticles for Photovoltaic Application
Authors: Wided Zerguine, Farid Habelhames
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The performance of photovoltaic devices with a light absorber consisting of a single-type conjugated polymer is poor, due to a low photo-generation yield of charge carriers, strong radiative recombination’s and low mobility of charge carriers. Recently, it has been shown that ultra-fast photoinduced charge transfer can also occur between a conjugated polymer and a metal oxide semiconductor such as SnO2, TiO2, ZnO, Nb2O5, etc. This has led to the fabrication of photovoltaic devices based on composites of oxide semiconductor nanoparticles embedded in a conjugated polymer matrix. In this work, Poly [2-methoxy-5-(20-ethylhexyloxy)-p-phenylenevinylene] (MEH-PPV), (6,6)-phenyl-C61-butyric acid methyl ester (PCBM) and titanium dioxide (TiO2) nanoparticles (n-type) were dissolved, mixed and deposited by physical methods (spin-coating) on indium tin-oxide (ITO) substrate. The incorporation of the titanium dioxide nanoparticles changed the morphology and increased the roughness of polymers film (MEH-PPV/PCBM), and the photocurrent density of the composite (MEH-PPV/PCBM +n-TiO2) was higher than that of single MEHPPV/ PCBM film. The study showed that the presence of n-TiO2 particles in the polymeric film improves the photoelectrochemical properties of MEH-PPV/PCBM composite.Keywords: photocurrent density, organic nanostructures, hybrid coating, conducting polymer, titanium dioxide
Procedia PDF Downloads 3291943 A Comparative Study on a Tilt-Integral-Derivative Controller with Proportional-Integral-Derivative Controller for a Pacemaker
Authors: Aysan Esgandanian, Sabalan Daneshvar
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The study is done to determine the comparison between proportional-integral-derivative controller (PID controller) and tilt-integral-derivative (TID controller) for cardiac pacemaker systems, which can automatically control the heart rate to accurately track a desired preset profile. The controller offers good adaption of heart to the physiological needs of the patient. The parameters of the both controllers are tuned by particle swarm optimization (PSO) algorithm which uses the integral of time square error as a fitness function to be minimized. Simulation results are performed on the developed cardiovascular system of humans and results demonstrate that the TID controller produces superior control performance than PID controllers. In this paper, all simulations were performed in Matlab.Keywords: integral of time square error, pacemaker systems, proportional-integral-derivative controller, PSO algorithm, tilt-integral-derivative controller
Procedia PDF Downloads 4631942 Logistics Hub Location and Scheduling Model for Urban Last-Mile Deliveries
Authors: Anastasios Charisis, Evangelos Kaisar, Steven Spana, Lili Du
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Logistics play a vital role in the prosperity of today’s cities, but current urban logistics practices are proving problematic, causing negative effects such as traffic congestion and environmental impacts. This paper proposes an alternative urban logistics system, leasing hubs inside cities for designated time intervals, and using handcarts for last-mile deliveries. A mathematical model for selecting the locations of hubs and allocating customers, while also scheduling the optimal times during the day for leasing hubs is developed. The proposed model is compared to current delivery methods requiring door-to-door truck deliveries. It is shown that truck traveled distances decrease by more than 60%. In addition, analysis shows that in certain conditions the approach can be economically competitive and successfully applied to address real problems.Keywords: hub location, last-mile, logistics, optimization
Procedia PDF Downloads 1961941 Shifting Paradigms of Culture: Rise of Secular Sensibility in Indian Literature
Authors: Nidhi Chouhan
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Burgeoning demand of ‘Secularism’ has shaken the pillars of cultural studies in the contemporary literature. The perplexity of the culturally estranged term ‘secular’ gives rise to temporal ideologies across the world. Hence, it is high time to scan this concept in the context of Indian lifestyle which is a blend of assimilated cultures woven in multiple religious fabrics. The infliction of such secular taste is depicted in literary productions like ‘Satanic Verses’ and ‘An Area of Darkness’. The paper conceptually makes a cross-cultural analysis of anti-religious Indian literary texts, assessing its revitalization in current times. Further, this paper studies the increasing popularity of secular sensibility in the contemporary times. The mushrooming elements of secularism such as abstraction, spirituality, liberation, individualism give rise to a seemingly newer idea i.e. ‘Plurality’ making the literature highly hybrid. This approach has been used to study Indian modernity reflected in its literature. Seminal works of stalwarts are used to understand the consequence of this cultural synthesis. Conclusively, this theoretical research inspects the efficiency of secular culture, intertwined with internal coherence and throws light on the plurality of texts in Indian literature.Keywords: culture, indian, literature, plurality, secular, secularism
Procedia PDF Downloads 1061940 Field Saturation Flow Measurement Using Dynamic Passenger Car Unit under Mixed Traffic Condition
Authors: Ramesh Chandra Majhi
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Saturation flow is a very important input variable for the design of signalized intersections. Saturation flow measurement is well established for homogeneous traffic. However, saturation flow measurement and modeling is a challenging task in heterogeneous characterized by multiple vehicle types and non-lane based movement. Present study focuses on proposing a field procedure for Saturation flow measurement and the effect of typical mixed traffic behavior at the signal as far as non-lane based traffic movement is concerned. Data collected during peak and off-peak hour from five intersections with varying approach width is used for validating the saturation flow model. The insights from the study can be used for modeling saturation flow and delay at signalized intersection in heterogeneous traffic conditions.Keywords: optimization, passenger car unit, saturation flow, signalized intersection
Procedia PDF Downloads 3271939 Model Based Development of a Processing Map for Friction Stir Welding of AA7075
Authors: Elizabeth Hoyos, Hernán Alvarez, Diana Lopez, Yesid Montoya
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The main goal of this research relates to the modeling of FSW from a different or unusual perspective coming from mechanical engineering, particularly looking for a way to establish process windows by assessing soundness of the joints as a priority and with the added advantage of lower computational time. This paper presents the use of a previously developed model applied to specific aspects of soundness evaluation of AA7075 FSW welds. EMSO software (Environment for Modeling, Simulation, and Optimization) was used for simulation and an adapted CNC machine was used for actual welding. This model based approach showed good agreement with the experimental data, from which it is possible to set a window of operation for commercial aluminum alloy AA7075, all with low computational costs and employing simple quality indicators that can be used by non-specialized users in process modeling.Keywords: aluminum AA7075, friction stir welding, phenomenological based semiphysical model, processing map
Procedia PDF Downloads 2611938 Optimization of Waqf Land through Sukuk Al-Intifa’ to Build MSMEs in Indonesia
Authors: Khadijah Hasim, Achmad Fauzan Firdaus, Choirunnisa
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Waqf land which previously was idle assets can be built on top of a building that is a means for people to conduct business. Nadzir (waqf managers) lease of waqf lands it manages, the agreed rental fee, which is payable in the form of the building, not in cash. After standing building, the developer will lease to interested companies. Given the magnitude of the beginning funds needed, The company later issuing sukuk al-intifa on the trading floor. With this sukuk issuance, the company has sufficient capital to begin operations and pay obligations of the rental fee to the developer each year. Building that had stood trade area will be established (Micro, Small, Middle Entreprises) MSMEs. It is expected that through the sukuk al-intifa, can help to make waqf land previously unproductive due to lack of capital to be very beneficial and help awaken the people of Indonesian MSMEsKeywords: Sukuk Al-Intifa, MSMEs, waqf land, underlying asset
Procedia PDF Downloads 4711937 “BUM629” Special Hybrid Reinforcement Materials for Mega Structures
Authors: Gautam, Arjun, V. R. Sharma
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In the civil construction steel and concrete plays a different role but the same purposes dealing with the design of structures that support or resist loads. Concrete has been used in construction since long time from now. Being brittle and weak in tension, concrete is always reinforced with steel bars for the purposes in beams and columns etc. The paper deals with idea of special designed 3D materials which we named as “BUM629” to be placed/anchored in the structural member and mixed with concrete later on, so as to resist the developments of cracks due to shear failure , buckling,tension and compressive load in concrete. It had cutting edge technology through Draft, Analysis and Design the “BUM629”. The results show that “BUM629” has the great results in Mechanical application. Its material properties are design according to the need of structure; we apply the material such as Mild Steel and Magnesium Alloy. “BUM629” are divided into two parts one is applied at the middle section of concrete member where bending movements are maximum and the second part is laying parallel to vertical bars near clear cover, so we design this material and apply in Reinforcement of Civil Structures. “BUM629” is analysis and design for use in the mega structures like skyscrapers, dams and bridges.Keywords: BUM629, magnesium alloy, cutting edge technology, mechanical application, draft, analysis and design, mega structures
Procedia PDF Downloads 3841936 Studies on Optimization of Batch Biosorption of Cr (VI) and Cu (II) from Wastewater Using Bacillus subtilis
Authors: Narasimhulu Korrapati
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The objective of this present study is to optimize the process parameters for batch biosorption of Cr(VI) and Cu(II) ions by Bacillus subtilis using Response Surface Methodology (RSM). Batch biosorption studies were conducted under optimum pH, temperature, biomass concentration and contact time for the removal of Cr(VI) and Cu(II) ions using Bacillus subtilis. From the studies it is noticed that the maximum biosorption of Cr(VI) and Cu(II) was by Bacillus subtilis at optimum conditions of contact time of 30 minutes, pH of 4.0, biomass concentration of 2.0 mg/mL, the temperature of 32°C in batch biosorption studies. Predicted percent biosorption of the selected heavy metal ions by the design expert software is in agreement with experimental results of percent biosorption. The percent biosorption of Cr(VI) and Cu(II) in batch studies is 80% and 78.4%, respectively.Keywords: heavy metal ions, response surface methodology, biosorption, wastewater
Procedia PDF Downloads 2741935 Optimization of the Energy Management for a Solar System of an Agricultural Greenhouse
Authors: Nora Arbaoui, Rachid Tadili, Ilham Ihoume
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To improve the climatic conditions and increase production in the greenhouse during the winter season under the Mediterranean climate, this thesis project proposes a design of an integrated and autonomous solar system for heating, cooling, and conservation of production in an agricultural greenhouse. To study the effectiveness of this system, experiments are conducted in two similar agricultural greenhouses oriented north-south. The first greenhouse is equipped with an active solar system integrated into the double glazing of the greenhouse’s roof, while the second greenhouse has no system, it serves as a controlled greenhouse for comparing thermal and agronomic performance The solar system allowed for an average increase in the indoor temperature of the experimental greenhouse of 6°C compared to the outdoor environment and 4°C compared to the control greenhouse. This improvement in temperature has a favorable effect on the plants' climate and subsequently positively affects their development, quality, and production.Keywords: solar system, agricultural greenhouse, heating, cooling, storage, drying
Procedia PDF Downloads 1011934 Formal Implementation of Routing Information Protocol Using Event-B
Authors: Jawid Ahmad Baktash, Tadashi Shiroma, Tomokazu Nagata, Yuji Taniguchi, Morikazu Nakamura
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The goal of this paper is to explore the use of formal methods for Dynamic Routing, The purpose of network communication with dynamic routing is sending a massage from one node to others by using pacific protocols. In dynamic routing connections are possible based on protocols of Distance vector (Routing Information Protocol, Border Gateway protocol), Link State (Open Shortest Path First, Intermediate system Intermediate System), Hybrid (Enhanced Interior Gateway Routing Protocol). The responsibility for proper verification becomes crucial with Dynamic Routing. Formal methods can play an essential role in the Routing, development of Networks and testing of distributed systems. Event-B is a formal technique consists of describing rigorously the problem; introduce solutions or details in the refinement steps to obtain more concrete specification, and verifying that proposed solutions are correct. The system is modeled in terms of an abstract state space using variables with set theoretic types and the events that modify state variables. Event-B is a variant of B, was designed for developing distributed systems. In Event-B, the events consist of guarded actions occurring spontaneously rather than being invoked. The invariant state properties must be satisfied by the variables and maintained by the activation of the events.Keywords: dynamic rout RIP, formal method, event-B, pro-B
Procedia PDF Downloads 4031933 Modelling the Indonesian Goverment Securities Yield Curve Using Nelson-Siegel-Svensson and Support Vector Regression
Authors: Jamilatuzzahro, Rezzy Eko Caraka
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The yield curve is the plot of the yield to maturity of zero-coupon bonds against maturity. In practice, the yield curve is not observed but must be extracted from observed bond prices for a set of (usually) incomplete maturities. There exist many methodologies and theory to analyze of yield curve. We use two methods (the Nelson-Siegel Method, the Svensson Method, and the SVR method) in order to construct and compare our zero-coupon yield curves. The objectives of this research were: (i) to study the adequacy of NSS model and SVR to Indonesian government bonds data, (ii) to choose the best optimization or estimation method for NSS model and SVR. To obtain that objective, this research was done by the following steps: data preparation, cleaning or filtering data, modeling, and model evaluation.Keywords: support vector regression, Nelson-Siegel-Svensson, yield curve, Indonesian government
Procedia PDF Downloads 2461932 Towards Developing Social Assessment Tool for Siwan Ecolodge Case Study: Babenshal Ecolodge
Authors: Amr Ali Bayoumi, Ola Ali Bayoumi
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The aim of this research is enhancing one of the main aspects (Social Aspect) for developing an eco-lodge in Siwa oasis in Egyptian Western Desert. According to credible weightings built in this research through formal and informal questionnaires, the researcher detected one of the highest credible aspects, 'Social Aspect': through which it carries the maximum priorities among the total environmental and economic categories. From here, the researcher suggested the usage of ethnographic design approach and Space Syntax as observational and computational methods for developing future Eco-lodge in Siwa Oasis. These methods are used to study social spaces of Babenshal eco-lodge as a case study. This hybrid method is considered as a beginning of building Social Assessment Tool (SAT) for ecological tourism buildings located in Siwa as a case of Egyptian Western desert community. Towards livable social spaces, the proposed SAT was planned to be the optimum measurable weightings for social aspect's priorities of future Siwan eco-lodge(s). Finally, recommendations are proposed for enhancing SAT to be more correlated with sensitive desert biome (Siwa Oasis) to be adapted with the continuous social and environmental changes of the oasis.Keywords: ecolodge, social aspect, space syntax, Siwa Oasis
Procedia PDF Downloads 1281931 Filtering Intrusion Detection Alarms Using Ant Clustering Approach
Authors: Ghodhbani Salah, Jemili Farah
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With the growth of cyber attacks, information safety has become an important issue all over the world. Many firms rely on security technologies such as intrusion detection systems (IDSs) to manage information technology security risks. IDSs are considered to be the last line of defense to secure a network and play a very important role in detecting large number of attacks. However the main problem with today’s most popular commercial IDSs is generating high volume of alerts and huge number of false positives. This drawback has become the main motivation for many research papers in IDS area. Hence, in this paper we present a data mining technique to assist network administrators to analyze and reduce false positive alarms that are produced by an IDS and increase detection accuracy. Our data mining technique is unsupervised clustering method based on hybrid ANT algorithm. This algorithm discovers clusters of intruders’ behavior without prior knowledge of a possible number of classes, then we apply K-means algorithm to improve the convergence of the ANT clustering. Experimental results on real dataset show that our proposed approach is efficient with high detection rate and low false alarm rate.Keywords: intrusion detection system, alarm filtering, ANT class, ant clustering, intruders’ behaviors, false alarms
Procedia PDF Downloads 4051930 A Heuristic Approach for the General Flowshop Scheduling Problem to Minimize the Makespan
Authors: Mohsen Ziaee
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Almost all existing researches on the flowshop scheduling problems focus on the permutation schedules and there is insufficient study dedicated to the general flowshop scheduling problems in the literature, since the modeling and solving of the general flowshop scheduling problems are more difficult than the permutation ones, especially for the large-size problem instances. This paper considers the general flowshop scheduling problem with the objective function of the makespan (F//Cmax). We first find the optimal solution of the problem by solving a mixed integer linear programming model. An efficient heuristic method is then presented to solve the problem. An ant colony optimization algorithm is also proposed for the problem. In order to evaluate the performance of the methods, computational experiments are designed and performed. Numerical results show that the heuristic algorithm can result in reasonable solutions with low computational effort and even achieve optimal solutions in some cases.Keywords: scheduling, general flow shop scheduling problem, makespan, heuristic
Procedia PDF Downloads 2071929 Biogas Separation, Alcohol Amine Solutions
Authors: Jingxiao Liang, David Rooneyman
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Biogas, which is a valuable renewable energy source, can be produced by anaerobic fermentation of agricultural waste, manure, municipal waste, plant material, sewage, green waste, or food waste. It is composed of methane (CH4) and carbon dioxide (CO2) but also contains significant quantities of undesirable compounds such as hydrogen sulfide (H2S), ammonia (NH3), and siloxanes. Since typical raw biogas contains 25–45% CO2, The requirements for biogas quality depend on its further application. Before biogas is being used more efficiently, CO2 should be removed. One of the existing options for biogas separation technologies is based on chemical absorbents, in particular, mono-, di- and tri-alcohol amine solutions. Such amine solutions have been applied as highly efficient CO2 capturing agents. The benchmark in this experiment is N-methyldiethanolamine (MDEA) with piperazine (PZ) as an activator, from CO2 absorption Isotherm curve, optimization conditions are collected, such as activator percentage, temperature etc. This experiment makes new alcohol amines, which could have the same CO2 absorbing ability as activated MDEA, using glycidol as one of reactant, the result is quite satisfying.Keywords: biogas, CO2, MDEA, separation
Procedia PDF Downloads 6371928 Additive Manufacturing of Overhangs: From Temporary Supports to Self-Support
Authors: Paulo Mendonca, Nzar Faiq Naqeshbandi
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The objective of this study is to propose an interactive design environment that outlines the underlying computational framework to reach self-supporting overhangs. The research demonstrates the digital printability of overhangs taking into consideration factors related to the geometry design, the material used, the applied support, and the printing set-up of slicing and the extruder inclination. Parametric design tools can contribute to the design phase, form-finding, and stability optimization of self-supporting structures while printing in order to hold the components in place until they are sufficiently advanced to support themselves. The challenge is to ensure the stability of the printed parts in the critical inclinations during the whole fabrication process. Facilitating the identification of parameterization will allow to predict and optimize the process. Later, in the light of the previous findings, some guidelines of simulations and physical tests are given to be conducted for estimating the structural and functional performance.Keywords: additive manufacturing, overhangs, self-support overhangs, printability, parametric tools
Procedia PDF Downloads 1221927 Synthesis of Chitosan/Silver Nanocomposites: Antibacterial Properties and Tissue Regeneration for Thermal Burn Injury
Authors: B.L. España-Sánchez, E. Luna-Hernández, R.A. Mauricio-Sánchez, M.E. Cruz-Soto, F. Padilla-Vaca, R. Muñoz, L. Granados-López, L.R. Ovalle-Flores, J.L. Menchaca-Arredondo, G. Luna-Bárcenas
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Treatment of burn injured has been considered an important clinical problem due to the fluid control and the presence of microorganisms during the healing process. Conventional treatment includes antiseptic techniques, topical medication and surgical removal of damaged skin, to avoid bacterial growth. In order to accelerate this process, different alternatives for tissue regeneration have been explored, including artificial skin, polymers, hydrogels and hybrid materials. Some requirements consider a nonreactive organic polymer with high biocompatibility and skin adherence, avoiding bacterial infections. Chitin-derivative biopolymer such as chitosan (CS) has been used in skin regeneration following third-degree burns. The biological interest of CS is associated with the improvement of tissue cell stimulation, biocompatibility and antibacterial properties. In particular, antimicrobial properties of CS can be significantly increased when is blended with nanostructured materials. Silver-based nanocomposites have gained attention in medicine due to their high antibacterial properties against pathogens, related to their high surface area/volume ratio at nanomolar concentrations. Silver nanocomposites can be blended or synthesized with chitin-derivative biopolymers in order to obtain a biodegradable/antimicrobial hybrid with improved physic-mechanical properties. In this study, nanocomposites based on chitosan/silver nanoparticles (CS/nAg) were synthesized by the in situ chemical reduction method, improving their antibacterial properties against pathogenic bacteria and enhancing the healing process in thermal burn injuries produced in an animal model. CS/nAg was prepared in solution by the chemical reduction method, using AgNO₃ as precursor. CS was dissolved in acetic acid and mixed with different molar concentrations of AgNO₃: 0.01, 0.025, 0.05 and 0.1 M. Solutions were stirred at 95°C during 20 hours, in order to promote the nAg formation. CS/nAg solutions were placed in Petri dishes and dried, to obtain films. Structural analyses confirm the synthesis of silver nanoparticles (nAg) by means of UV-Vis and TEM, with an average size of 7.5 nm and spherical morphology. FTIR analyses showed the complex formation by the interaction of hydroxyl and amine groups with metallic nanoparticles, and surface chemical analysis (XPS) shows low concentration of Ag⁰/Ag⁺ species. Topography surface analyses by means of AFM shown that hydrated CS form a mesh with an average diameter of 10 µm. Antibacterial activity against S. aureus and P. aeruginosa was improved in all evaluated conditions, such as nAg loading and interaction time. CS/nAg nanocomposites films did not show Ag⁰/Ag⁺ release in saline buffer and rat serum after exposition during 7 days. Healing process was significantly enhanced by the presence of CS/nAg nanocomposites, inducing the production of myofibloblasts, collagen remodelation, blood vessels neoformation and epidermis regeneration after 7 days of injury treatment, by means of histological and immunohistochemistry assays. The present work suggests that hydrated CS/nAg nanocomposites can be formed a mesh, improving the bacterial penetration and the contact with embedded nAg, producing complete growth inhibition after 1.5 hours. Furthermore, CS/nAg nanocomposites improve the cell tissue regeneration in thermal burn injuries induced in rats. Synthesis of antibacterial, non-toxic, and biocompatible nanocomposites can be an important issue in tissue engineering and health care applications.Keywords: antibacterial, chitosan, healing process, nanocomposites, silver
Procedia PDF Downloads 2881926 An Efficient Algorithm for Global Alignment of Protein-Protein Interaction Networks
Authors: Duc Dong Do, Ngoc Ha Tran, Thanh Hai Dang, Cao Cuong Dang, Xuan Huan Hoang
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Global aligning two protein-protein interaction networks is an essentially important task in bioinformatics/computational biology field of study. It is a challenging and widely studied research topic in recent years. Accurately aligned networks allow us to identify functional modules of proteins and/ororthologous proteins from which unknown functions of a protein can be inferred. We here introduce a novel efficient heuristic global network alignment algorithm called FASTAn, including two phases: the first to construct an initial alignment and the second to improve such alignment by exerting a local optimization repeated procedure. The experimental results demonstrated that FASTAn outperformed the state-of-the-art global network alignment algorithm namely SPINAL in terms of both commonly used objective scores and the run-time.Keywords: FASTAn, Heuristic algorithm, biological network alignment, protein-protein interaction networks
Procedia PDF Downloads 6061925 Scheduling Tasks in Embedded Systems Based on NoC Architecture
Authors: D. Dorota
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This paper presents a method to generate and schedule task in the architecture of embedded systems based on the simulated annealing. This method takes into account the attribute of divisibility of tasks. A proposal represents the process in the form of trees. Despite the fact that the architecture of Network-on-Chip (NoC) is an interesting alternative to a bus architecture based on multi-processors systems, it requires a lot of work that ensures the optimization of communication. This paper proposes an effective approach to generate dedicated NoC topology solving communication problems. Network NoC is generated taking into account the energy consumption and resource issues. Ultimately generated is minimal, dedicated NoC topology. The proposed solution is assumed to be a simple router design and the minimum number of lines.Keywords: Network-on-Chip, NoC-based embedded systems, scheduling task in embedded systems, simulated annealing
Procedia PDF Downloads 3791924 Axial Flux Permanent Magnet Motor Design and Optimization by Using Artificial Neural Networks
Authors: Tugce Talay, Kadir Erkan
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In this study, the necessary steps for the design of axial flow permanent magnet motors are shown. The design and analysis of the engine were carried out based on ANSYS Maxwell program. The design parameters of the ANSYS Maxwell program and the artificial neural network system were established in MATLAB and the most efficient design parameters were found with the trained neural network. The results of the Maxwell program and the results of the artificial neural networks are compared and optimal working design parameters are found. The most efficient design parameters were submitted to the ANSYS Maxwell 3D design and the cogging torque was examined and design studies were carried out to reduce the cogging torque.Keywords: AFPM, ANSYS Maxwell, cogging torque, design optimisation, efficiency, NNTOOL
Procedia PDF Downloads 2211923 Modeling the Compound Interest Dynamics Using Fractional Differential Equations
Authors: Muath Awadalla, Maen Awadallah
Abstract:
Banking sector covers different activities including lending money to customers. However, it is commonly known that customers pay money they have borrowed including an added amount called interest. Compound interest rate is an approach used in determining the interest to be paid. The instant compounded amount to be paid by a debtor is obtained through a differential equation whose main parameters are the rate and the time. The rate used by banks in a country is often defined by the government of the said country. In Switzerland, for instance, a negative rate was once applied. In this work, a new approach of modeling the compound interest is proposed using Hadamard fractional derivative. As a result, it appears that depending on the fraction value used in derivative the amount to be paid by a debtor might either be higher or lesser than the amount determined using the classical approach.Keywords: compound interest, fractional differential equation, hadamard fractional derivative, optimization
Procedia PDF Downloads 1261922 Dynamics Behavior of DFIG Wind Energy Conversion System Incase Dip Voltage
Authors: N. Zerzouri, N. Benalia, N. Bensiali
Abstract:
During recent years wind turbine technology has undergone rapid developments. Growth in size and the optimization of wind turbines has enabled wind energy to become increasingly competitive with conventional energy sources. As a result today’s wind turbines participate actively in the power production of several countries around the world. These developments raise a number of challenges to be dealt with now and in the future. The penetration of wind energy in the grid raises questions about the compatibility of the wind turbine power production with the grid. In particular, the contribution to grid stability, power quality and behavior during fault situations plays therefore as important a role as the reliability. In the present work, we addressed two fault situations that have shown their influence on the generator and the behavior of the wind over the defects which are briefly discussed based on simulation results.Keywords: doubly fed induction generator (DFIG), wind energy, grid fault, electrical engineering
Procedia PDF Downloads 471