Search results for: closed form solution.
2254 The Role of Ga(Gallium)-flux and AlN(Aluminum Nitride) as the Interface Materials, between (Ga-face)GaN and (Siface)4H-SiC, through Molecular Dynamics Simulation
Authors: Srikanta Bose, Sudip K. Mazumder
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We report here, the results of molecular dynamics simulation of p-doped (Ga-face)GaN over n-doped (Siface)( 0001)4H-SiC hetero-epitaxial material system with one-layer each of Ga-flux and (Al-face)AlN, as the interface materials, in the form of, the total Density of States (DOS). It is found that the total DOS at the Fermi-level for the heavily p-doped (Ga-face)GaN and ndoped (Si-face)4H-SiC hetero-epitaxial system, with one layer of (Al-face)AlN as the interface material, is comparatively higher than that of the various cases studied, indicating that there could be good vertical conduction across the (Ga-face)GaN over (Si-face)(0001)4HSiC hetero-epitaxial material system.Keywords: Molecular dynamics, GaN, 4H-SiC, hetero-epitaxy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20122253 Supporting QoS-aware Multicasting in Differentiated Service Networks
Authors: Manas Ranjan Kabat, Rajib Mall, Chita Ranjan Tripathy
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A scalable QoS aware multicast deployment in DiffServ networks has become an important research dimension in recent years. Although multicasting and differentiated services are two complementary technologies, the integration of the two technologies is a non-trivial task due to architectural conflicts between them. A popular solution proposed is to extend the functionality of the DiffServ components to support multicasting. In this paper, we propose an algorithm to construct an efficient QoSdriven multicast tree, taking into account the available bandwidth per service class. We also present an efficient way to provision the limited available bandwidth for supporting heterogeneous users. The proposed mechanism is evaluated using simulated tests. The simulated result reveals that our algorithm can effectively minimize the bandwidth use and transmission costKeywords: Differentiated Services, multicasting, QoSheterogeneity, DSCP
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14902252 Improving the Dissolution Rate of Folic Acid via the Antisolvent Vapour Precipitation
Authors: J. Y. Tan, L. C. Lum, M. G. Lee, S. Mansouri, K. Hapgood, X. D. Chen, M. W. Woo
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Folic acid (FA) is known to be an important supplement to prevent neural tube defect (NTD) in pregnant women. Similar to some commercial formulations, sodium bicarbonate solution is used as a solvent for FA. This work uses the antisolvent vapour precipitation (AVP), incorporating ethanol vapour as the convective drying medium in place of air to produce branch-like micro-structure FA particles. Interestingly, the dissolution rate of the resultant particle is 2-3 times better than the particle produce from conventional air drying due to the higher surface area of particles produced. The higher dissolution rate could possibly improve the delivery and absorption of FA in human body. This application could potentially be extended to other commercial products, particularly in less soluble drugs to improve its solubility.
Keywords: Absorption, antisolvent vapour precipitation, dissolution rate, folic acid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24702251 Sfard’s Commognitive Framework as a Method of Discourse Analysis in Mathematics
Authors: Dong-Joong Kim, Sangho Choi, Woong Lim
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This paper discusses Sfard’s commognitive approach and provides an empirical study as an example to illustrate the theory as method. Traditionally, research in mathematics education focused on the acquisition of mathematical knowledge and the didactic process of knowledge transfer. Through attending to a distinctive form of language in mathematics, as well as mathematics as a discursive subject, alternative views of making meaning in mathematics have emerged; these views are therefore “critical,” as in critical discourse analysis. The commognitive discourse analysis method has the potential to bring more clarity to our understanding of students’ mathematical thinking and the process through which students are socialized into school mathematics.
Keywords: Commognitive framework, discourse analysis, mathematical discourse, mathematics education.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21912250 Numerical Studies of Galerkin-type Time-discretizations Applied to Transient Convection-diffusion-reaction Equations
Authors: Naveed Ahmed, Gunar Matthies
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We deal with the numerical solution of time-dependent convection-diffusion-reaction equations. We combine the local projection stabilization method for the space discretization with two different time discretization schemes: the continuous Galerkin-Petrov (cGP) method and the discontinuous Galerkin (dG) method of polynomial of degree k. We establish the optimal error estimates and present numerical results which shows that the cGP(k) and dG(k)- methods are accurate of order k +1, respectively, in the whole time interval. Moreover, the cGP(k)-method is superconvergent of order 2k and dG(k)-method is of order 2k +1 at the discrete time points. Furthermore, the dependence of the results on the choice of the stabilization parameter are discussed and compared.
Keywords: Convection-diffusion-reaction equations, stabilized finite elements, discontinuous Galerkin, continuous Galerkin-Petrov.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17512249 Application of SDS/LABS in Recovery Improvement from Fractured Models
Authors: Rasool Razmi, Mohammad Hossein Sedaghat, Reza Janamiri, Amir Hatampou
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This work concerns on experimentally investigation of surfactant flooding in fractured porous media. In this study a series of water and surfactant injection processes were performed on micromodels initially saturated with a heavy crude oil. Eight fractured glass micromodels were used to illustrate effects of surfactant types and concentrations on oil recovery efficiency in presence of fractures with different properties i.e. fracture orientation, length and number of fractures. Two different surfactants with different concentrations were tested. The results showed that surfactant flooding would be more efficient by using SDS surfactant aqueous solution and also by locating injection well in a proper position respect to fracture properties. This study demonstrates different physical and chemical conditions that affect the efficiency of this method of enhanced oil recovery.Keywords: Displacement, Fractured five-spot systems, Heavy oil, Surfactant flooding.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18942248 Digital Sites- Performative Views
Authors: Gavin Perin, Linda Matthews
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Webcam systems now function as the new privileged vantage points from which to view the city. This transformation of CCTV technology from surveillance to promotional tool is significant because its'scopic regime' presents, back to the public, a new virtual 'site' that sits alongside its real-time counterpart. Significantly, thisraw 'image' data can, in fact,be co-optedand processed so as to disrupt their original purpose. This paper will demonstrate this disruptive capacity through an architectural project. It will reveal how the adaption the webcam image offers a technical springboard by which to initiate alternate urban form making decisions and subvert the disciplinary reliance on the 'flat' orthographic plan. In so doing, the paper will show how this 'digital material' exceeds the imagistic function of the image; shiftingit from being a vehicle of signification to a site of affect.Keywords: Surveillance, virtual, scopic, additive
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12852247 Analytical Investigation of the Effects of a Standing Ocean Wave in a Wave-Power Device OWC
Authors: E.G. Bautista, F. Méndez, O. Bautista, J.C. Arcos
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In this work we study analytically and numerically the performance of the mean heave motion of an OWC coupled with the governing equation of the spreading ocean waves due to the wide variation in an open parabolic channel with constant depth. This paper considers that the ocean wave propagation is under the assumption of a shallow flow condition. In order to verify the effect of the waves in the OWC firstly we establish the analytical model in a non-dimensional form based on the energy equation. The proposed wave-power system has to aims: one is to perturb the ocean waves as a consequence of the channel shape in order to concentrate the maximum ocean wave amplitude in the neighborhood of the OWC and the second is to determine the pressure and volume oscillation of air inside the compression chamber.Keywords: Oscillating water column, Shallow flow, Waveenergy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14672246 A Pragmatics Study on Jokes and the Implicature in Broadcast Messages
Authors: Yuli Widiana
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The study of implicature which is one of the discussions of pragmatics is such an interesting and challenging topic to discuss. Implicature is such a meaning which is implied in such an utterance which is not the same as its literal meaning. The rapid development of information technology results social networks as media to broadcast messages. The broadcast messages may be in the form of jokes which contain implicature. The research applies the pragmatic equivalent method to analyze the topics of jokes based on the implicatures contained in them. Furthermore, the method is also applied to reveal the purpose of creating implicature in jokes. The findings include the kinds of implicature found in jokes which are classified into conventional implicature and conversational implicature. Then, in detailed analysis, implicature in jokes is divided into implicature related to gender, culture, and social phenomena. Furthermore, implicature in jokes may not only be used to give entertainment but also to soften criticisms or satire so that it does not sound rude and harsh.Keywords: Implicature, broadcast messages, conventional implicature, conversational implicature.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32772245 The Fluid Limit of the Critical Processor Sharing Tandem Queue
Authors: Amal Ezzidani, Abdelghani Ben Tahar, Mohamed Hanini
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A sequence of finite tandem queue is considered for this study. Each one has a single server, which operates under the egalitarian processor sharing discipline. External customers arrive at each queue according to a renewal input process and having a general service times distribution. Upon completing service, customers leave the current queue and enter to the next. Under mild assumptions, including critical data, we prove the existence and the uniqueness of the fluid solution. For asymptotic behavior, we provide necessary and sufficient conditions for the invariant state and the convergence to this invariant state. In the end, we establish the convergence of a correctly normalized state process to a fluid limit characterized by a system of algebraic and integral equations.Keywords: Fluid Limit, fluid model, measure valued process, processor sharing, tandem queue.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4772244 Effect of Information System Strategies on Supply Chain Strategies and Supply Chain Performance
Authors: M. Torabizadeh, M. Khatami Rad, A. Noshadi
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In order to achieve competitive advantage and better performance of firm, supply chain management (SCM) strategy should support and drive forward business strategy. It means that supply chain should be aligned with business strategy, at the same time supply chain (SC) managers need to use appropriate information system (IS) solution to support their strategy, which would lead to stay competitive. There are different kinds of IS strategies which enable managers to meet the SC requirement by selecting the best IS strategy. Therefore, it is important to align IS strategies and practices with SC strategies and practices, which could help us to plan for an IS application that supports and enhances a SCMS. In this study, aligning IS with SC in strategy level is considered. The main aim of this paper is to align the various IS strategies with SCM strategies and demonstrate their impact on SC and firm performance.Keywords: Information system strategy, alignment, firm performance, supply chain strategy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18412243 Numerical Simulation of Fluid Structure Interaction Using Two-Way Method
Authors: Samira Laidaoui, Mohammed Djermane, Nazihe Terfaya
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The fluid-structure coupling is a natural phenomenon which reflects the effects of two continuums: fluid and structure of different types in the reciprocal action on each other, involving knowledge of elasticity and fluid mechanics. The solution for such problems is based on the relations of continuum mechanics and is mostly solved with numerical methods. It is a computational challenge to solve such problems because of the complex geometries, intricate physics of fluids, and complicated fluid-structure interactions. The way in which the interaction between fluid and solid is described gives the largest opportunity for reducing the computational effort. In this paper, a problem of fluid structure interaction is investigated with two-way coupling method. The formulation Arbitrary Lagrangian-Eulerian (ALE) was used, by considering a dynamic grid, where the solid is described by a Lagrangian formulation and the fluid by a Eulerian formulation. The simulation was made on the ANSYS software.
Keywords: ALE, coupling, FEM, fluid-structure interaction, one-way method, two-way method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15122242 PSO-based Possibilistic Portfolio Model with Transaction Costs
Authors: Wei Chen, Cui-you Yao, Yue Qiu
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This paper deals with a portfolio selection problem based on the possibility theory under the assumption that the returns of assets are LR-type fuzzy numbers. A possibilistic portfolio model with transaction costs is proposed, in which the possibilistic mean value of the return is termed measure of investment return, and the possibilistic variance of the return is termed measure of investment risk. Due to considering transaction costs, the existing traditional optimization algorithms usually fail to find the optimal solution efficiently and heuristic algorithms can be the best method. Therefore, a particle swarm optimization is designed to solve the corresponding optimization problem. At last, a numerical example is given to illustrate our proposed effective means and approaches.Keywords: Possibility theory, portfolio selection, transaction costs, particle swarm optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15342241 Measurement of Steady Streaming from an Oscillating Bubble Using Particle Image Velocimetry
Authors: Yongseok Kwon, Woowon Jeong, Eunjin Cho, Sangkug Chung, Kyehan Rhee
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Steady streaming flow fields induced by a 500 mm bubble oscillating at 12 kHz were measured using microscopic particle image velocimetry (PIV). The accuracy of velocity measurement using a micro PIV system was checked by comparing the measured velocity fields with the theoretical velocity profiles in fully developed laminar flow. The steady streaming flow velocities were measured in the sagittal plane of the bubble attached on the wall. Measured velocity fields showed upward jet flow with two symmetric counter-rotating vortices, and the maximum streaming velocity was about 12 mm/s, which was within the velocity ranges measured by other researchers. The measured streamlines were compared with the analytical solution, and they also showed a reasonable agreement.
Keywords: Oscillating bubble, Particle-Image-Velocimetry microstreaming.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18182240 Generation Scheduling Optimization of Multi-Hydroplants: A Case Study
Authors: Shuangquan Liu, Jinwen Wang, Dada Wang
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A case study of the generation scheduling optimization of the multi-hydroplants on the Yuan River Basin in China is reported in this paper. Concerning the uncertainty of the inflows, the long/mid-term generation scheduling (LMTGS) problem is solved by a stochastic model in which the inflows are considered as stochastic variables. For the short-term generation scheduling (STGS) problem, a constraint violation priority is defined in case not all constraints are satisfied. Provided the stage-wise separable condition and low dimensions, the hydroplant-based operational region schedules (HBORS) problem is solved by dynamic programming (DP). The coordination of LMTGS and STGS is presented as well. The feasibility and the effectiveness of the models and solution methods are verified by the numerical results.Keywords: generation scheduling, multi-hydroplants, optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15512239 From Mother Tongue Education to Multilingual Higher Education
Authors: Mario R. Acevedo Amaya, Fernanda M. Martinez Reyes
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Through the time, the higher education has changed the learning system since mother tongue to bilingual, and in this new century has been coming develop a multilingual education. All as part of globalization process of the countries and the education. Nevertheless, this change only has been effectively in countries of the first world, the rest have been lagging. Therefore, these countries require strengthen their higher education systems through models that give way to multilingual and bilingual education. In this way, shows a new model adapted from a systemic form to allow a higher bilingual and multilingual education in Latin America. This systematization aims to increase the skills and competencies student’s, decrease the time learning of a second tongue, add to multilingualism in the American Latin Universities, also, contribute to position the region´s countries in a better global status, and stimulate the development of new research in this area.Keywords: Bilingual Education, Higher Education, Multilingual Education, Multilingual Education Model
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19332238 Social Commerce – E-Commerce in Social Media Context
Authors: Linda Sau-ling LAI
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This paper aims to address the new trend of social commerce as electronic commerce leverages Web 2.0 technologies and online social media. The infusions of new technologies on the World Wide Web connect users in their homes and workplaces, thus transforming social formations and business transactions. An in-depth study of the growth and success of a social commerce site, Facebook was conducted. The investigation is finalized with a triad relational model which reflects socioeconomic life in the Internet today. The following three concepts work jointly to form a global community that has already started to take the place of traditional commerce and socialization: Web 2.0 technology, E-commerce, and online social media. A discussion of the research findings indicates that social commerce networks are sustainable because of the various incentives given to users as they collaborate with others regardless of their identity and location. The focus of this article is to increase understanding on quickly developing Web 2.0 based social media and their subsequent effects on the emerging social commerce.Keywords: Social Commerce, Web 2.0, ElectronicCommerce, Social Media
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 76242237 Separation of Dissolved Gases from Water for a Portable Underwater Breathing
Authors: Pil Woo Heo, In Sub Park
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Water contains oxygen which may make a human breathe under water like a fish. Centrifugal separator can separate dissolved gases from water. Carrier solution can increase the separation of dissolved oxygen from water. But, to develop an breathing device for a human under water, the enhancement of separation of dissolved gases including oxygen and portable devices which have dc battery based device and proper size are needed. In this study, we set up experimental device for analyzing separation characteristics of dissolved gases including oxygen from water using a battery based portable vacuum pump. We characterized vacuum state, flow rate of separation of dissolved gases and oxygen concentration which were influenced by the manufactured vacuum pump.
Keywords: Portable, breathing, water, separation, battery.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20982236 A Dual Digital-Image Watermarking Technique
Authors: Maha Sharkas, Dahlia ElShafie, Nadder Hamdy
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Image watermarking has become an important tool for intellectual property protection and authentication. In this paper a watermarking technique is suggested that incorporates two watermarks in a host image for improved protection and robustness. A watermark, in form of a PN sequence (will be called the secondary watermark), is embedded in the wavelet domain of a primary watermark before being embedded in the host image. The technique has been tested using Lena image as a host and the camera man as the primary watermark. The embedded PN sequence was detectable through correlation among other five sequences where a PSNR of 44.1065 dB was measured. Furthermore, to test the robustness of the technique, the watermarked image was exposed to four types of attacks, namely compression, low pass filtering, salt and pepper noise and luminance change. In all cases the secondary watermark was easy to detect even when the primary one is severely distorted.Keywords: DWT, Image watermarking, watermarkingtechniques, wavelets.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27112235 The Importance of Issues for the Youth in Voter Decision Making: A Case Study among University Students in Malaysia
Authors: Sivamurugan Pandian
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In the 13th Malaysia’s General Elections held in 2013, it was observed that large numbers of urban constituencies saw strongly decisive young voters (between 21-39 age group) determine the outcome in their favour. Also, the Elections Commission had approximated that 70% of some 4.2 million unregistered voters at the time were citizens aged between 21 and 40 years old. If they are not already considered an important form of political leverage, 450,000 young Malaysians turn 21 years old each year. Further compounding this fact were the 2.4 million new voters registered in 2012, which at the time constituted almost 30% of the entire voting population. This article discusses the importance of issues for the youth, with reference to the university students in Malaysia in their decision making on polling day.
Keywords: Malaysia, Youth, Issues, Voting Patterns, Elections.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35482234 Mathematical Model and Solution Algorithm for Containership Operation/Maintenance Scheduling
Authors: Hun Go, Ji-Su Kim, Dong-Ho Lee
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This study considers the problem of determining operation and maintenance schedules for a containership equipped with components during its sailing according to a pre-determined navigation schedule. The operation schedule, which specifies work time of each component, determines the due-date of each maintenance activity, and the maintenance schedule specifies the actual start time of each maintenance activity. The main constraints are component requirements, workforce availability, working time limitation, and inter-maintenance time. To represent the problem mathematically, a mixed integer programming model is developed. Then, due to the problem complexity, we suggest a heuristic for the objective of minimizing the sum of earliness and tardiness between the due-date and the starting time of each maintenance activity. Computational experiments were done on various test instances and the results are reported.Keywords: Containerships, operation and preventive maintenance schedules, integer programming, heuristic
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16152233 Performance Analysis of Absorption Power Cycle under Different Source Temperatures
Authors: Kyoung Hoon Kim
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The absorption power generation cycle based on the ammonia-water mixture has attracted much attention for efficient recovery of low-grade energy sources. In this paper a thermodynamic performance analysis is carried out for a Kalina cycle using ammonia-water mixture as a working fluid for efficient conversion of low-temperature heat source in the form of sensible energy. The effects of the source temperature on the system performance are extensively investigated by using the thermodynamic models. The results show that the source temperature as well as the ammonia mass fraction affects greatly on the thermodynamic performance of the cycle.
Keywords: Ammonia-water mixture, Kalina cycle, low-grade heat source, source temperature.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24642232 Application of the Improved QFD Method Case Study: Kitchen Utensils Rack Design
Authors: Dini Endah Setyo Rahaju, Dian Retno Sari Dewi
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This paper presents an application of the improved QFD method for determining the specifications of kitchen utensils rack. By using the improved method, the subjective nature in original QFD was reduced; particularly in defining the relationship between customer requirement and engineering characteristics. The regression analysis that was used for obtaining the relationship functions between customer requirement and engineering characteristics also accommodated the inaccurateness of the competitive assessment results. The improved method which is represented in the form of a mathematical model had become a formal guidance to allocate the resource for improving the specifications of kitchen utensils rack. The specifications obtained had led to the achievement of the highest feasible customer satisfaction.
Keywords: Customer satisfaction, kitchen utensils rack design, QFD, specifications.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16322231 Ads on Social Issues: A Tool for Improving Critical Thinking Skills in a Foreign Language Classroom
Authors: Fonseca Jully, Chia Maribel, Rodríguez Ilba
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This paper is a qualitative research report. A group of students form a public university in a small town in Colombia participated in this study which aimed at describing to what extend the use of social ads, published on the internet, helped to develop their critical thinking skills. Students’ productions, field notes, video recordings and direct observation were the instruments and techniques used by the researches in order to gather the data which was analyzed under the principles of grounded theory and triangulation. The implementation of social ads into the classroom evidenced a noticeable improvement in students’ ability to interpret and argue social issues, as well as, their self-improvement in oral and written production in English, as a foreign language.Keywords: Ads, critical argumentation, critical thinking, social issues.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18192230 Pricing Strategy Selection Using Fuzzy Linear Programming
Authors: Elif Alaybeyoğlu, Y. Esra Albayrak
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Marketing establishes a communication network between producers and consumers. Nowadays, marketing approach is customer-focused and products are directly oriented to meet customer needs. Marketing, which is a long process, needs organization and management. Therefore strategic marketing planning becomes more and more important in today’s competitive conditions. Main focus of this paper is to evaluate pricing strategies and select the best pricing strategy solution while considering internal and external factors influencing the company’s pricing decisions associated with new product development. To reflect the decision maker’s subjective preference information and to determine the weight vector of factors (attributes), the fuzzy linear programming technique for multidimensional analysis of preference (LINMAP) under intuitionistic fuzzy (IF) environments is used.
Keywords: IF Sets, LINMAP, MAGDM, Marketing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22642229 Enhanced Weighted Centroid Localization Algorithm for Indoor Environments
Authors: I. Nižetić Kosović, T. Jagušt
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Lately, with the increasing number of location-based applications, demand for highly accurate and reliable indoor localization became urgent. This is a challenging problem, due to the measurement variance which is the consequence of various factors like obstacles, equipment properties and environmental changes in complex nature of indoor environments. In this paper we propose low-cost custom-setup infrastructure solution and localization algorithm based on the Weighted Centroid Localization (WCL) method. Localization accuracy is increased by several enhancements: calibration of RSSI values gained from wireless nodes, repetitive measurements of RSSI to exclude deviating values from the position estimation, and by considering orientation of the device according to the wireless nodes. We conducted several experiments to evaluate the proposed algorithm. High accuracy of ~1m was achieved.
Keywords: Indoor environment, received signal strength indicator, weighted centroid localization, wireless localization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31042228 Investigation of Solvent Effect on Viscosity of Lubricant in Disposable Medical Devices
Authors: Hamed Bagheri, Seyd Javid Shariati
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The effects of type and amount of solvent on lubricant which is used in disposable medical devices are investigated in this article. Two kinds of common solvent, n-Hexane and n-Heptane, are used. The mechanical behavior of syringe has shown that n-Heptane has better mixing ratio and also more effective spray process in the barrel of syringe than n-Hexane because of similar solubility parameter to silicon oil. The results revealed that movement of plunger in the barrel increases when pure silicone is used because non-uniform film is created on the surface of barrel, and also, it seems that the form of silicon is converted from oil to gel due to sterilization process. The results showed that the convenient mixing ratio of solvent/lubricant oil is 80/20.
Keywords: Disposable medical devices, lubricant oil, solvent effect, solubility parameter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13942227 Morphology Study of Inverted Planar Heterojunction Perovskite Solar Cells in Sequential Deposition
Authors: Asmat Nawaz, Ali Koray Erdinc, Burak Gultekin, Muhammad Tayyib, Ceylan Zafer, Kaiying Wang, M. Nadeem Akram
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In this study, a sequential deposition process is used for the fabrication of PEDOT: PSS based inverted planar perovskite solar cell. A small amount of additive deionized water (DI-H2O) was added into PbI2 + Dimethyl formamide (DMF) precursor solution in order to increase the solubility of PbI2 in DMF, and finally to manipulate the surface morphology of the perovskite films. A morphology transition from needle like structure to hexagonal plates, and then needle-like again has been observed as the DI-H2O was added continuously (0.0 wt% to 3.0wt%). The latter one leads to full surface coverage of the perovskite, which is essential for high performance solar cell.Keywords: Charge carrier diffusion lengths, methylamonium lead iodide, precursor composition, perovskite solar cell, sequential deposition.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16772226 Risk and Uncertainty in Aviation: A Thorough Analysis of System Vulnerabilities
Authors: C. V. Pietreanu, S. E. Zaharia, C. Dinu
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Hazard assessment and risks quantification are key components for estimating the impact of existing regulations. But since regulatory compliance cannot cover all risks in aviation, the authors point out that by studying causal factors and eliminating uncertainty, an accurate analysis can be outlined. The research debuts by making delimitations on notions, as confusion on the terms over time has reflected in less rigorous analysis. Throughout this paper, it will be emphasized the fact that the variation in human performance and organizational factors represent the biggest threat from an operational perspective. Therefore, advanced risk assessment methods analyzed by the authors aim to understand vulnerabilities of the system given by a nonlinear behavior. Ultimately, the mathematical modeling of existing hazards and risks by eliminating uncertainty implies establishing an optimal solution (i.e. risk minimization).
Keywords: Control, human factor, optimization, risk management, uncertainty.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16232225 A Planning Model for Evacuation in Building
Authors: Hsin-Yun Lee, Hao-Hsi Tseng
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Previous studies mass evacuation route network does not fully reflect the step-by-step behavior and evacuees make routing decisions. Therefore, they do not work as expected when applied to the evacuation route planning is valid. This article describes where evacuees may have to make a direction to select all areas were identified as guiding points to improve evacuation routes network. This improved route network can be used as a basis for the layout can be used to guide the signs indicate that provides the required evacuation direction. This article also describes that combines simulation and artificial bee colony algorithm to provide the proposed routing solutions, to plan an integrated routing mode. The improved network and the model used is the cinema as a case study to assess the floor. The effectiveness of guidance solution in the total evacuation time is significant by verification.
Keywords: Artificial bee colony, Evacuation, Simulation.
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