Search results for: Renewable Energy Technology.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5176

Search results for: Renewable Energy Technology.

1726 Bee Optimized Fuzzy Geographical Routing Protocol for VANET

Authors: P. Saravanan, T. Arunkumar

Abstract:

Vehicular Adhoc Network (VANET) is a new technology which aims to ensure intelligent inter-vehicle communications, seamless internet connectivity leading to improved road safety, essential alerts, and access to comfort and entertainment. VANET operations are hindered by mobile node’s (vehicles) uncertain mobility. Routing algorithms use metrics to evaluate which path is best for packets to travel. Metrics like path length (hop count), delay, reliability, bandwidth, and load determine optimal route. The proposed scheme exploits link quality, traffic density, and intersections as routing metrics to determine next hop. This study enhances Geographical Routing Protocol (GRP) using fuzzy controllers while rules are optimized with Bee Swarm Optimization (BSO). Simulations results are compared to conventional GRP.

Keywords: Bee Swarm Optimization (BSO), Geographical Routing Protocol (GRP), Vehicular Adhoc Network (VANET).

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1725 Urban Environmental Challenges in Developing Cities: The Case of Ethiopian Capital Addis Ababa

Authors: Dubbale Daniel A., Tsutsumi J., Michael J. Bendewald

Abstract:

Addis Ababa is a seat of African Union (AU), United Nations Economic Commission for Africa (UN-ECA) and hundreds of embassies and consular representatives. Addis Ababa is one of the highest capitals in the world with an average 2400 meters above sea level. It is dichotomous city with a blend of modern high-rise and deteriorating slum quarters. Water supply and sanitation, waste management and housing are continuing to be serious problems. Forest wood based domestic energy use as well as uncontrolled emissions from mobile and fixed sources has endangered the state of the urban environment. Analysis based on satellite imagery has revealed the deteriorating urban environment within the last three decades. The recently restructured city administration has brought improvements in the condition of the urban environment. However, the overwhelming size of the challenges faced by the city dwarfed their fairly good results.

Keywords: Addis Ababa, Urban environment, Slum, Housing, Relocation

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1724 Thermodynamic, Structural and Transport Properties of Molten Copper-Thallium Alloys

Authors: D. Adhikari, R. P. Koirala, B.P. Singh

Abstract:

A self-association model has been used to understand the concentration dependence of free energy of mixing (GM), heat of mixing (HM), entropy of mixing (SM), activity (a) and microscopic structures, such as concentration fluctuation in long wavelength limit (Scc(0)) and Warren-Cowley short range order parameter ( 1 α )for Cu- Tl molten alloys at 1573K. A comparative study of surface tension of the alloys in the liquid state at that temperature has also been carried out theoretically as function of composition in the light of Butler-s model, Prasad-s model and quasi-chemical approach. Most of the computed thermodynamic properties have been found in agreement with the experimental values. The analysis reveals that the Cu-Tl molten alloys at 1573K represent a segregating system at all concentrations with moderate interaction. Surface tensions computed from different approaches have been found to be comparable to each other showing increment with the composition of copper.

Keywords: Concentration fluctuations, surface tension, thermodynamic properties, Quasi-chemical approximation.

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1723 Model Predictive Control of Gantry Crane with Input Nonlinearity Compensation

Authors: Steven W. Su , Hung Nguyen, Rob Jarman, Joe Zhu, David Lowe, Peter McLean, Shoudong Huang, Nghia T. Nguyen, Russell Nicholson, Kaili Weng

Abstract:

This paper proposed a nonlinear model predictive control (MPC) method for the control of gantry crane. One of the main motivations to apply MPC to control gantry crane is based on its ability to handle control constraints for multivariable systems. A pre-compensator is constructed to compensate the input nonlinearity (nonsymmetric dead zone with saturation) by using its inverse function. By well tuning the weighting function matrices, the control system can properly compromise the control between crane position and swing angle. The proposed control algorithm was implemented for the control of gantry crane system in System Control Lab of University of Technology, Sydney (UTS), and achieved desired experimental results.

Keywords: Model Predictive Control, Control constraints, Input nonlinearity compensation, Overhead gantry crane.

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1722 Communicative and Artistic Machines: A Survey of Models and Experiments on Artificial Agents

Authors: Artur Matuck, Guilherme F. Nobre

Abstract:

Machines can be either tool, media, or social agents. Advances in technology have been delivering machines capable of autonomous expression, both through communication and art. This paper deals with models (theoretical approach) and experiments (applied approach) related to artificial agents. On one hand it traces how social sciences' scholars have worked with topics such as text automatization, man-machine writing cooperation, and communication. On the other hand it covers how computer sciences' scholars have built communicative and artistic machines, including the programming of creativity. The aim is to present a brief survey on artificially intelligent communicators and artificially creative writers, and provide the basis to understand the meta-authorship and also to new and further man-machine co-authorship.

Keywords: Artificial communication, artificial creativity, artificial writers, meta-authorship, robotic art.

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1721 The Application of Bayesian Heuristic for Scheduling in Real-Time Private Clouds

Authors: Sahar Sohrabi

Abstract:

The emergence of Cloud data centers has revolutionized the IT industry. Private Clouds in specific provide Cloud services for certain group of customers/businesses. In a real-time private Cloud each task that is given to the system has a deadline that desirably should not be violated. Scheduling tasks in a real-time private CLoud determine the way available resources in the system are shared among incoming tasks. The aim of the scheduling policy is to optimize the system outcome which for a real-time private Cloud can include: energy consumption, deadline violation, execution time and the number of host switches. Different scheduling policies can be used for scheduling. Each lead to a sub-optimal outcome in a certain settings of the system. A Bayesian Scheduling strategy is proposed for scheduling to further improve the system outcome. The Bayesian strategy showed to outperform all selected policies. It also has the flexibility in dealing with complex pattern of incoming task and has the ability to adapt.

Keywords: Bayesian, cloud computing, real-time private cloud, scheduling.

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1720 Cost Optimization of Concentric Braced Steel Building Structures

Authors: T. Balogh, L. G. Vigh

Abstract:

Seismic design may require non-conventional concept, due to the fact that the stiffness and layout of the structure have a great effect on the overall structural behaviour, on the seismic load intensity as well as on the internal force distribution. To find an economical and optimal structural configuration the key issue is the optimal design of the lateral load resisting system. This paper focuses on the optimal design of regular, concentric braced frame (CBF) multi-storey steel building structures. The optimal configurations are determined by a numerical method using genetic algorithm approach, developed by the authors. Aim is to find structural configurations with minimum structural cost. The design constraints of objective function are assigned in accordance with Eurocode 3 and Eurocode 8 guidelines. In this paper the results are presented for various building geometries, different seismic intensities, and levels of energy dissipation.

Keywords: Dissipative Structures, Genetic Algorithm, Seismic Effects, Structural Optimization.

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1719 Laser Welding of Titanium Alloy Ti64 to Polyamide 6.6: Effects of Welding Parameters on Temperature Profile Evolution

Authors: A. Al-Sayyad, P. Lama, J. Bardon, P. Hirchenhahn, L. Houssiau, P. Plapper

Abstract:

Composite metal–polymer materials, in particular titanium alloy (Ti-6Al-4V) to polyamide (PA6.6), fabricated by laser joining, have gained cogent interest among industries and researchers concerned with aerospace and biomedical applications. This work adopts infrared (IR) thermography technique to investigate effects of laser parameters used in the welding process on the three-dimensional temperature profile at the rear-side of titanium, at the region to be welded with polyamide. Cross sectional analysis of welded joints showed correlations between the morphology of titanium and polyamide at the weld zone with the corresponding temperature profile. In particular, spatial temperature profile was found to be correlated with the laser beam energy density, titanium molten pool width and depth, and polyamide heat affected zone depth.

Keywords: Laser welding, metals to polymers joining, process monitoring, temperature profile, thermography.

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1718 Information Extraction from Unstructured and Ungrammatical Data Sources for Semantic Annotation

Authors: Quratulain N. Rajput, Sajjad Haider, Nasir Touheed

Abstract:

The internet has become an attractive avenue for global e-business, e-learning, knowledge sharing, etc. Due to continuous increase in the volume of web content, it is not practically possible for a user to extract information by browsing and integrating data from a huge amount of web sources retrieved by the existing search engines. The semantic web technology enables advancement in information extraction by providing a suite of tools to integrate data from different sources. To take full advantage of semantic web, it is necessary to annotate existing web pages into semantic web pages. This research develops a tool, named OWIE (Ontology-based Web Information Extraction), for semantic web annotation using domain specific ontologies. The tool automatically extracts information from html pages with the help of pre-defined ontologies and gives them semantic representation. Two case studies have been conducted to analyze the accuracy of OWIE.

Keywords: Ontology, Semantic Annotation, Wrapper, Information Extraction.

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1717 Dynamics of a Vapour Bubble inside a Vertical Rigid Cylinder with a Deposit Rib

Authors: S. Mehran, S. Rouhi, F.Rouzbahani, E. Haghgoo

Abstract:

In this paper dynamics of a vapour bubble generated due to a local energy input inside a vertical rigid cylinder and in the absence of buoyancy forces is investigated. Different ratios of the diameter of the rigid cylinder to the maximum radius of the bubble are considered. The Boundary Integral Equation Method is employed for numerical simulation of the problem. Results show that during the collapse phase of the bubble inside a vertical rigid cylinder, two liquid micro jets are developed on the top and bottom sides of the vapour bubble and are directed inward. Results also show that existence of a deposit rib inside the vertical rigid cylinder slightly increases the life time of the bubble. It is found that by increasing the ratio of the cylinder diameter to the maximum radius of the bubble, the rate of the growth and collapse phases of the bubble increases and the life time of the bubble decreases.

Keywords: Vapour bubble, Vertical rigid cylinder, Boundaryelement method.

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1716 Investigation of Dissolution in Diammonium Hydrogen Phosphate Solutions of Gypsum

Authors: Turan Çalban, Nursel Keskin, Sabri Çolak, Soner Kuşlu

Abstract:

Gypsum (CaSO4.2H2O) is a mineral that is found in large quantities in the Turkey and in the World. In this study, the dissolution of this mineral in the diammonium hydrogen phosphate solutions has been studied. The dissolution and dissolution kinetics of gypsum in diammonium hydrogen phosphate solutions will be useful for evaluating of solid wastes containing gypsum. Parameters such as diammonium hydrogen phosphate concentration, temperature and stirring speed affecting on the dissolution rate of the gypsum in diammonium hydrogen phosphate solutions were investigated. In experimental studies have researched effectiveness of the selected parameters. The dissolution of gypsum were examined in two parts at low and high temperatures. The experimental results were successfully correlated by linear regression using Statistica program. Dissolution curves were evaluated shrinking core models for solidfluid systems. The activation energy was found to be 34.58 kJ/mol and 44.45 kJ/mol for the low and the high temperatures. The dissolution of gypsum was controlled by chemical reaction both low temperatures and high temperatures.

Keywords: Diammonium hydrogen phosphate, Dissolution, Gypsum, Kinetics.

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1715 Communication in a Heterogeneous Ad Hoc Network

Authors: C. Benjbara, A. Habbani

Abstract:

Wireless networks are getting more and more used in every new technology or feature, especially those without infrastructure (Ad hoc mode) which provide a low cost alternative to the infrastructure mode wireless networks and a great flexibility for application domains such as environmental monitoring, smart cities, precision agriculture, and so on. These application domains present a common characteristic which is the need of coexistence and intercommunication between modules belonging to different types of ad hoc networks like wireless sensor networks, mesh networks, mobile ad hoc networks, vehicular ad hoc networks, etc. This vision to bring to life such heterogeneous networks will make humanity duties easier but its development path is full of challenges. One of these challenges is the communication complexity between its components due to the lack of common or compatible protocols standard. This article proposes a new patented routing protocol based on the OLSR standard in order to resolve the heterogeneous ad hoc networks communication issue. This new protocol is applied on a specific network architecture composed of MANET, VANET, and FANET.

Keywords: Ad hoc, heterogeneous, ID-Node, OLSR.

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1714 Theoretical Investigations on Different Casing and Rotor Diameters Ratio to Optimize Shaft Output of a Vaned Type Air Turbine

Authors: Bharat Raj Singh, Onkar Singh

Abstract:

This paper details a new concept of using compressed air as a potential zero pollution power source for motorbikes. In place of an internal combustion engine, the motorbike is equipped with an air turbine transforms the energy of the compressed air into shaft work. The mathematical modeling and performance evaluation of a small capacity compressed air driven vaned type novel air turbine is presented in this paper. The effect of isobaric admission and adiabatic expansion of high pressure air for different rotor diameters, casing diameters and ratio of rotor to casing diameters of the turbine have been considered and analyzed. It is concluded that the work output is found optimum for some typical values of rotor / casing diameter ratios. In this study, the maximum power works out to 3.825 kW (5.20 HP) for casing diameter of 200 mm and rotor to casing diameter ratio of 0.65 to 0.60 which is sufficient to run motorbike.

Keywords: zero pollution, compressed air, air turbine, injectionangle, rotor / casing diameter ratio.

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1713 Significant Role Analysis of Transmission Control Protocols in 4G Cellular Systems

Authors: Ghassan A. Abed, Bayan M. Sabbar

Abstract:

The society of 3rd Generation Partnership Project (3GPP) is completed developing Long Term Evolution Advanced (LTE-Advanced) systems as a standard 4G cellular system. This generation goals to produce conditions for a new radio-access technology geared to higher data rates, low latency, and better spectral efficiency. LTE-Advanced is an evolutionary step in the continuing development of LTE where the description in this article is based on LTE release 10. This paper provides a model of the traffic links of 4G system represented by LTE-Advanced system with the effect of the Transmission Control Protocols (TCP) and Stream Control Transmission Protocol (SCTP) in term of throughput and packet loss. Furthermore, the article presents the investigation and the analysis the behavior of SCTP and TCP variants over the 4G cellular systems. The traffic model and the scenario of the simulation developed using the network simulator NS-2 using different TCP source variants.

Keywords: LTE-Advanced, LTE, SCTP, TCP, 4G, NS-2.

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1712 Strengthening and Toughening of Dental Porcelain by the Inclusion of an Yttria-Stabilized Zirconia Reinforcing Phase

Authors: Bruno Henriques, Rafaela Santos, Mihaela Buciumeanu, Júlio Matias de Souza, Filipe Silva, Rubens Nascimento, Márcio Fredel

Abstract:

Dental porcelain composites reinforced and toughened by 20 wt.% tetragonal zirconia (3Y-TZP) were processed by hot pressing at 1000°C. Two types of particles were tested: yttriastabilized zirconia (ZrO2–3%Y2O3) agglomerates and pre-sintered yttria-stabilized zirconia (ZrO2–3%Y2O3) particles. The composites as well as the reinforcing particles were analyzed by the means of optical and Scanning Electron Microscopy (SEM), Energy Dispersion Spectroscopy (EDS) and X-Ray Diffraction (XRD). The mechanical properties were obtained by the transverse rupture strength test. Wear tests were also performed on the composites and monolithic porcelain. The best mechanical results were displayed by the porcelain reinforced with the pre-sintered ZrO2–3%Y2O3 agglomerates.

Keywords: Composite, dental restoration, porcelain, strengthening, toughening, wear, zirconia.

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1711 Improvement in Performance and Emission Characteristics of a Single Cylinder S.I. Engine Operated on Blends of CNG and Hydrogen

Authors: Sarbjot Singh Sandhu

Abstract:

This paper presents the experimental results of a single cylinder Enfield engine using an electronically controlled fuel injection system which was developed to carry out exhaustive tests using neat CNG, and mixtures of hydrogen in compressed natural gas (HCNG) as 0, 5, 10, 15 and 20% by energy. Experiments were performed at 2000 and 2400 rpm with wide open throttle and varying the equivalence ratio. Hydrogen which has fast burning rate, when added to compressed natural gas, enhances its flame propagation rate. The emissions of HC, CO, decreased with increasing percentage of hydrogen but NOx was found to increase. The results indicated a marked improvement in the brake thermal efficiency with the increase in percentage of hydrogen added. The improved thermal efficiency was clearly observed to be more in lean region as compared to rich region. This study is expected to reduce vehicular emissions along with increase in thermal efficiency and thus help in reduction of further environmental degradation.

Keywords: Hydrogen, CNG, HCNG, Emissions.

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1710 Automatic Light Control in Domotics using Artificial Neural Networks

Authors: Carlos Machado, José A. Mendes

Abstract:

Home Automation is a field that, among other subjects, is concerned with the comfort, security and energy requirements of private homes. The configuration of automatic functions in this type of houses is not always simple to its inhabitants requiring the initial setup and regular adjustments. In this work, the ubiquitous computing system vision is used, where the users- action patterns are captured, recorded and used to create the contextawareness that allows the self-configuration of the home automation system. The system will try to free the users from setup adjustments as the home tries to adapt to its inhabitants- real habits. In this paper it is described a completely automated process to determine the light state and act on them, taking in account the users- daily habits. Artificial Neural Network (ANN) is used as a pattern recognition method, classifying for each moment the light state. The work presented uses data from a real house where a family is actually living.

Keywords: ANN, Home Automation, Neural Systems, PatternRecognition, Ubiquitous Computing.

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1709 Performance of Single Pass Down Stream Solar Air Collector with Inclined Multiple V-Ribs

Authors: Manivannan A, Velmurugan M

Abstract:

Solar air heater is a type of heat exchanger which transforms solar radiation into heat energy. The thermal performance of conventional solar air heater has been found to be poor because of the low convective heat transfer coefficient from the absorber plate to the air. It is attributed to the formation of a very thin boundary layer at the absorber plate surface commonly known as viscous sub-layer. Thermal efficiency of solar air heater can be improved by providing the artificial roughness on absorber plate is the most efficient technique. In this paper an attempt is made to provide artificial roughness by incorporating inclined multiple V-ribs in the underside of the absorber plate. 60˚V – ribs are arranged inclined to the direction of air flow. Performance of collector estimated theoretically and experimentally. Results of the investigation reveal that thermal efficiency of collector with multiple V-ribs increased by 14%.

Keywords: Artificial roughness, inclined multiple V-ribs, performance, Solar air collector.

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1708 Characterization of Responsivity, Sensitivity and Spectral Response in Thin Film SOI photo-BJMOS -FET Compatible with CMOS Technology

Authors: Hai-Qing Xie, Yun Zeng, Yong-Hong Yan, Jian-Ping Zeng, Tai-Hong Wang

Abstract:

Photo-BJMOSFET (Bipolar Junction Metal-Oxide- Semiconductor Field Effect Transistor) fabricated on SOI film was proposed. ITO film is adopted in the device as gate electrode to reduce light absorption. Depletion region but not inversion region is formed in film by applying gate voltage (but low reverse voltage) to achieve high photo-to-dark-current ratio. Comparisons of photoelectriccharacteristics executed among VGK=0V, 0.3V, 0.6V, 0.9V and 1.0V (reverse voltage VAK is equal to 1.0V for total area of 10×10μm2). The results indicate that the greatest improvement in photo-to-dark-current ratio is achieved up to 2.38 at VGK=0.6V. In addition, photo-BJMOSFET is compatible with CMOS integration due to big input resistance

Keywords: Photo-BJMOSFET, Responsivity, Sensitivity, Spectral response.

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1707 A Study of the Costs and Benefits of Smart City Projects Including the Scenario of Public-Private Partnerships

Authors: Patrick T. I. Lam, Wenjing Yang

Abstract:

A smart city project embraces benefits and costs which can be classified under direct and indirect categories. Externalities come into the picture, but they are often difficult to quantify. Despite this barrier, policy makers need to carry out cost-benefit analysis to justify the huge investments needed to make a city smart. The recent trend is towards the engagement of the private sector to utilize their resources and expertise, especially in the Information and Communication Technology (ICT) areas, where innovations blossom. This study focuses on the identification of costs (on a life cycle basis) and benefits associated with smart city project developments based on a comprehensive literature review and case studies, where public-private partnerships would warrant consideration, the related costs and benefits are highlighted. The findings will be useful for policy makers of cities.

Keywords: Costs and benefits, identification, public-private partnerships, smart city projects.

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1706 Design of Power System Stabilizer with Neuro-Fuzzy UPFC Controller

Authors: U. Ramesh Babu, V. Vijay Kumar Reddy, S. Tara Kalyani

Abstract:

The growth in the demand of electrical energy is leading to load on the Power system which increases the occurrence of frequent oscillations in the system. The reason for the oscillations is due to the lack of damping torque which is required to dominate the disturbances of Power system. By using FACT devices, such as Unified Power Flow Controller (UPFC) can control power flow, reduce sub-synchronous resonances and increase transient stability. Hence, UPFC is used to damp the oscillations occurred in Power system. This research focuses on adapting the neuro fuzzy controller for the UPFC design by connecting the infinite bus (SMIB - Single machine Infinite Bus) to a linearized model of synchronous machine (Heffron-Phillips) in the power system. This model gains the capability to improve the transient stability and to damp the oscillations of the system.

Keywords: Power System, UPFC, (ANFIS) Adaptive Neuro Fuzzy Inference System, transient, Low frequency oscillations.

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1705 Experimental Test of a Combined Machine that Evenly Distributes Fertilizer under the Soil on Slopes

Authors: Qurbanov Huseyn Nuraddin

Abstract:

The results of scientific research on a machine that pours an equal amount of mineral fertilizer under the soil to increase the productivity of grain in mountain farming and obtain quality grain are substantiated. The average yield of the crop depends on the nature of the distribution of fertilizers in the soil. Therefore, the study of effective energy-saving methods for the application of mineral fertilizers is the actual task of modern agriculture. Depending on the type and variety of plants in mountain farming, there is an optimal norm of mineral fertilizers. Applying an equal amount of fertilizer to the soil is one of the conditions that increase the efficiency of the field. One of the main agro-technical indicators of the work of mineral fertilizing machines is to ensure equal distribution of mineral fertilizers in the field. Taking into account the above-mentioned issues, a combined plough has been improved in our laboratory.

Keywords: Combined plough, mineral fertilizers, sprinkle fluently, fertilizer rate, cereals.

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1704 Multi-Level Pulse Width Modulation to Boost the Power Efficiency of Switching Amplifiers for Analog Signals with Very High Crest Factor

Authors: Jan Doutreloigne

Abstract:

The main goal of this paper is to develop a switching amplifier with optimized power efficiency for analog signals with a very high crest factor such as audio or DSL signals. Theoretical calculations show that a switching amplifier architecture based on multi-level pulse width modulation outperforms all other types of linear or switching amplifiers in that respect. Simulations on a 2 W multi-level switching audio amplifier, designed in a 50 V 0.35 mm IC technology, confirm its superior performance in terms of power efficiency. A real silicon implementation of this audio amplifier design is currently underway to provide experimental validation.

Keywords: Audio amplifier, multi-level switching amplifier, power efficiency, pulse width modulation, PWM, self-oscillating amplifier.

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1703 Challenges and Opportunities of Cloud-Based E-Learning Systems

Authors: Kashif Laeeq, Zubair A. Shaikh

Abstract:

The paradigm of education is drastically changing from conventional to e-learning model. Due to ease of learning with various other benefits, several educational institutions are adopting the e-learning models. Some institutions are still willing to transform their educational system on to e-learning, but due to limited resources, they are still compromising on the old traditional system. The cloud computing could be one of the best solutions to overcome this problem by providing hardware, software, and infrastructure resources with cost efficient manner. The adoption of cloud computing in education will bring revolution in this paradigm. This paper introduces various positive features of e-learning and presents a way how cloud computing technology can be provisioned e-learning model. This paper also investigates the numerous challenges and opportunities that would be observed in cloud computing adoption in e-learning domain. The concept and knowledge present in this paper may create a new direction of research in the domain of cloud-based e-learning.

Keywords: Cloud-based e-learning, e-learning, cloud computing application, smart learning.

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1702 Learning Programming for Hearing Impaired Students via an Avatar

Authors: Nihal Esam Abuzinadah, Areej Abbas Malibari, Arwa Abdulaziz Allinjawi, Paul Krause

Abstract:

Deaf and hearing-impaired students face many obstacles throughout their education, especially with learning applied sciences such as computer programming. In addition, there is no clear signs in the Arabic Sign Language that can be used to identify programming logic terminologies such as while, for, case, switch etc. However, hearing disabilities should not be a barrier for studying purpose nowadays, especially with the rapid growth in educational technology. In this paper, we develop an Avatar based system to teach computer programming to deaf and hearing-impaired students using Arabic Signed language with new signs vocabulary that is been developed for computer programming education. The system is tested on a number of high school students and results showed the importance of visualization in increasing the comprehension or understanding of concepts for deaf students through the avatar.

Keywords: Hearing-impaired students, isolation, self-esteem, learning difficulties.

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1701 Air flow and Heat Transfer Modeling of an Axial Flux Permanent Magnet Generator

Authors: Airoldi G., Bumby J. R., Dominy C., G.L. Ingram, Lim C. H., Mahkamov K., N. L. Brown, A. Mebarki, M. Shanel

Abstract:

Axial Flux Permanent Magnet (AFPM) Machines require effective cooling due to their high power density. The detrimental effects of overheating such as degradation of the insulation materials, magnets demagnetization, and increase of Joule losses are well known. This paper describes the CFD simulations performed on a test rig model of an air cooled Axial Flux Permanent Magnet (AFPM) generator built at Durham University to identify the temperatures and heat transfer coefficient on the stator. The Reynolds Averaged Navier-Stokes and the Energy equations are solved and the flow pattern and heat transfer developing inside the machine are described. The Nusselt number on the stator surfaces has been found. The dependency of the heat transfer on the flow field is described temperature field obtained. Tests on an experimental are undergoing in order to validate the CFD results.

Keywords: Axial flux permanent magnet machines, thermal modeling, CFD.

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1700 Understanding Health Behavior Using Social Network Analysis

Authors: Namrata Mishra

Abstract:

Health of a person plays a vital role in the collective health of his community and hence the well-being of the society as a whole. But, in today’s fast paced technology driven world, health issues are increasingly being associated with human behaviors – their lifestyle. Social networks have tremendous impact on the health behavior of individuals. Many researchers have used social network analysis to understand human behavior that implicates their social and economic environments. It would be interesting to use a similar analysis to understand human behaviors that have health implications. This paper focuses on concepts of those behavioural analyses that have health implications using social networks analysis and provides possible algorithmic approaches. The results of these approaches can be used by the governing authorities for rolling out health plans, benefits and take preventive measures, while the pharmaceutical companies can target specific markets, helping health insurance companies to better model their insurance plans.

Keywords: Health behaviors, social network analysis, directed graph, breadth first search.

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1699 Experimental Verification and Finite Element Analysis of a Sliding Door System Used in Automotive Industry

Authors: C. Guven, M. Tufekci, E. Bayik, O. Gedik, M. Tas

Abstract:

A sliding door system is used in commercial vehicles and passenger cars to allow a larger unobstructed access to the interior for loading and unloading. The movement of a sliding door on vehicle body is ensured by mechanisms and tracks having special cross-section which is manufactured by roll forming and stretch bending process. There are three tracks and three mechanisms which are called upper, central and lower on a sliding door system. There are static requirements as strength on different directions, rigidity for mechanisms, door drop off, door sag; dynamic requirements as high energy slam opening-closing and durability requirement to validate these products. In addition, there is a kinematic requirement to find out force values from door handle during manual operating. In this study, finite element analysis and physical test results which are realized for sliding door systems will be shared comparatively.

Keywords: Finite element analysis, sliding door, experimental, verification, vehicle tests.

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1698 A Gnutella-based P2P System Using Cross-Layer Design for MANET

Authors: Ho-Hyun Park, Woosik Kim, Miae Woo

Abstract:

It is expected that ubiquitous era will come soon. A ubiquitous environment has features like peer-to-peer and nomadic environments. Such features can be represented by peer-to-peer systems and mobile ad-hoc networks (MANETs). The features of P2P systems and MANETs are similar, appealing for implementing P2P systems in MANET environment. It has been shown that, however, the performance of the P2P systems designed for wired networks do not perform satisfactorily in mobile ad-hoc environment. Subsequently, this paper proposes a method to improve P2P performance using cross-layer design and the goodness of a node as a peer. The proposed method uses routing metric as well as P2P metric to choose favorable peers to connect. It also utilizes proactive approach for distributing peer information. According to the simulation results, the proposed method provides higher query success rate, shorter query response time and less energy consumption by constructing an efficient overlay network.

Keywords: Ad-hoc Networks, Cross-layer, Peer-to-Peer, Performance Analysis.

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1697 Achieving Performance in an Organization through Marketing Innovation

Authors: Andreea Maier, Diana Nicoară, Dorin Maier, Maria-Mihaela Suărăsan, Alexandra Anastasiu

Abstract:

Innovation is becoming more and more important in modern society. There are a lot of researches on different kinds of innovation but marketing innovation is one kind of innovation that has not been studied frequently before. Marketing innovation is defined as a new way in which companies can market themselves to potential or existing customers. The study shows some key elements for marketing innovation that are worth paying attention to when implementing marketing innovation projects. Examples of such key elements are: paying attention to the neglected market, suitable market segmentatio reliable market information, public relationship, increased customer value, combination of market factors, explore different marketing channels and the use of technology in combination with what? Beside the key elements for marketing innovation, we also present some risks that may occur, such as cost, market uncertainty, information leakage, imitation and overdependence on experience. By proposing a set of indicators to measure marketing innovation, the article offers solutions for marketing innovation implementation so that any organization can achieve optimal results.

Keywords: Innovation, marketing innovation, performance in an organization.

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