Search results for: multiple choice objectives
1635 Improved Processing Speed for Text Watermarking Algorithm in Color Images
Authors: Hamza A. Al-Sewadi, Akram N. A. Aldakari
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Copyright protection and ownership proof of digital multimedia are achieved nowadays by digital watermarking techniques. A text watermarking algorithm for protecting the property rights and ownership judgment of color images is proposed in this paper. Embedding is achieved by inserting texts elements randomly into the color image as noise. The YIQ image processing model is found to be faster than other image processing methods, and hence, it is adopted for the embedding process. An optional choice of encrypting the text watermark before embedding is also suggested (in case required by some applications), where, the text can is encrypted using any enciphering technique adding more difficulty to hackers. Experiments resulted in embedding speed improvement of more than double the speed of other considered systems (such as least significant bit method, and separate color code methods), and a fairly acceptable level of peak signal to noise ratio (PSNR) with low mean square error values for watermarking purposes.
Keywords: Steganography, watermarking, private keys, time complexity measurements.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8161634 An Investigation of Quality Practices in Libyan Industrial Companies
Authors: Mostafa A. Shokshok, Omran Ali Abu Krais
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This paper describes the collection and analysis of data obtained from face-to-face interviews conducted in selected Libyan industrial companies. The objectives of the interviews are to enhance understanding, and generate explanations of current issues in culture and quality management systems in Libyan companies. The method used in analyzing the questions, as well as the main finding of each question are explained. The interviews probed areas identify national and organizational culture, quality management systems, current methods, effects, barriers and other factors affecting the success of quality management implementation. Eleven questions are prepared and been discussed with the interviewees.Keywords: Interviews, quality, culture, Libyan industrial companies.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19521633 Customer Satisfaction on Reliability Dimension of Service Quality in Indian Higher Education
Authors: Rajasekhar Mamilla, Janardhana G., Anjan Babu G.
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The present research study analyses the students’ satisfaction with university performance regarding the reliability dimension, ability of professors and staff to perform the promised services with quality to students in the post-graduate courses offered by Sri Venkateswara University in India. The research is done with the notion that the student compares the perceived performance with prior expectations. Customer satisfaction is seen as the outcome of this comparison. The sample respondents were administered with schedule based on stratified random technique for this study. Statistical techniques such as factor analysis, t-test and correlation analysis were used to accomplish the respective objectives of the study.
Keywords: Satisfaction, Reliability, Service Quality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 47281632 Selecting an Advanced Creep Model or a Sophisticated Time-Integration? A New Approach by Means of Sensitivity Analysis
Authors: Holger Keitel
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The prediction of long-term deformations of concrete and reinforced concrete structures has been a field of extensive research and several different creep models have been developed so far. Most of the models were developed for constant concrete stresses, thus, in case of varying stresses a specific superposition principle or time-integration, respectively, is necessary. Nowadays, when modeling concrete creep the engineering focus is rather on the application of sophisticated time-integration methods than choosing the more appropriate creep model. For this reason, this paper presents a method to quantify the uncertainties of creep prediction originating from the selection of creep models or from the time-integration methods. By adapting variance based global sensitivity analysis, a methodology is developed to quantify the influence of creep model selection or choice of time-integration method. Applying the developed method, general recommendations how to model creep behavior for varying stresses are given.
Keywords: Concrete creep models, time-integration methods, sensitivity analysis, prediction uncertainty.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15391631 Migration among Multicities
Authors: Ming Guan
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This paper proposes a simple model of economic geography within the Dixit-Stiglitz-Iceberg framework that may be used to analyze migration patterns among three cities. The cost–benefit tradeoffs affecting incentives for three types of migration, including echelon migration, are discussed. This paper develops a tractable, heterogeneous-agent, general equilibrium model, where agents share constant human capital, and explores the relationship between the benefits of echelon migration and gross human capital. Using Chinese numerical solutions, we study the manifestation of echelon migration and how it responds to changes in transportation cost and elasticity of substitution. Numerical results demonstrate that (i) there are positive relationships between a migration-s benefit-and-wage ratio, (ii) there are positive relationships between gross human capital ratios and wage ratios as to origin and destination, and (iii) we identify 13 varieties of human capital convergence among cities. In particular, this model predicts population shock resulting from the processes of migration choice and echelon migration.
Keywords: Dixit-Stiglitz-Iceberg framework, elasticity , echelonmigration, trade-off
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14761630 Comparison of MFCC and Cepstral Coefficients as a Feature Set for PCG Biometric Systems
Authors: Justin Leo Cheang Loong, Khazaimatol S Subari, Muhammad Kamil Abdullah, Nurul Nadia Ahmad, RosliBesar
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Heart sound is an acoustic signal and many techniques used nowadays for human recognition tasks borrow speech recognition techniques. One popular choice for feature extraction of accoustic signals is the Mel Frequency Cepstral Coefficients (MFCC) which maps the signal onto a non-linear Mel-Scale that mimics the human hearing. However the Mel-Scale is almost linear in the frequency region of heart sounds and thus should produce similar results with the standard cepstral coefficients (CC). In this paper, MFCC is investigated to see if it produces superior results for PCG based human identification system compared to CC. Results show that the MFCC system is still superior to CC despite linear filter-banks in the lower frequency range, giving up to 95% correct recognition rate for MFCC and 90% for CC. Further experiments show that the high recognition rate is due to the implementation of filter-banks and not from Mel-Scaling.Keywords: Biometric, Phonocardiogram, Cepstral Coefficients, Mel Frequency
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35531629 Investigating the Application of Social Sustainability: A Case Study in the Egyptian Retailing Sector
Authors: Lobna Hafez, Eman Elakkad
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Sustainability is no longer a choice for firms. To achieve sustainable supply chain, all three dimensions of sustainability should be considered. Unlike the economic and environmental aspects, social sustainability has been rarely given attention. The problem surrounding social sustainability and employees’ welfare in Egypt is complex and remains unsolved. The aim of this study is to qualitatively assess the current level of application of social sustainability in the retailing sector in Egypt through using the social sustainability indicators identified in the literature. The purpose of this investigation is to gain knowledge about the complexity of the system involved. A case study is conducted on one of the largest retailers in Egypt. Data were collected through semi-structured interviews with managers and employees to determine the level of application and identify the major obstacles affecting the social sustainability in the retailing context. The work developed gives insights about the details and complexities of the application of social sustainability in developing countries, from the retailing perspective. The outcomes of this study will help managers to understand the enablers of social sustainability and will direct them to methods of sound implementation.Keywords: Egypt, retailing sector, social sustainability, sustainability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5711628 Corporate Knowledge Communication and Knowledge Communication Difficulties
Authors: H. Buluthan Cetintas, M. Nejat Ozupek
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Communication is an important factor and a prop in directing corporate activities efficiently, in ensuring the flow of knowledge which is necessary for the continuity of the institution, in creating a common language in the institution, in transferring corporate culture and ultimately in corporate success. The idea of transmitting the knowledge among the workers in a healthy manner has revived knowledge communication. Knowledge communication can be defined as the act of mutual creation and communication of intuitions, assessments, experiences and capabilities, as long as maintained effectively, can provide advantages such as corporate continuity, access to corporate objectives and making true administrative decisions. Although the benefits of the knowledge communication to corporations are known, and the necessary worth and care is given, some hardships may arise which makes it difficult or even block it. In this article, difficulties that prevent knowledge communication will be discussed and solutions will be proposed.Keywords: Corporate knowledge communication, knowledge communication, knowledge communication barriers
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14391627 Optimal Voltage and Frequency Control of a Microgrid Using the Harmony Search Algorithm
Authors: Hossein Abbasi
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The stability is an important topic to plan and manage the energy in the microgrids as the same as the conventional power systems. The voltage and frequency stability is one of the most important issues recently studied in microgrids. The objectives of this paper are the modelling and designing of the components and optimal controllers for the voltage and frequency control of the AC/DC hybrid microgrid under the different disturbances. Since the PI controllers have the advantages of simple structure and easy implementation, so they are designed and modeled in this paper. The harmony search (HS) algorithm is used to optimize the controllers’ parameters. According to the achieved results, the PI controllers have a good performance in voltage and frequency control of the microgrid.
Keywords: Frequency control, HS algorithm, microgrid, PI controller, voltage control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13661626 Investigating the Possible use of Session Initiation Protocol for Extending Mobility Service to the Biomedical Engineers
Authors: Anwar Sadat
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Today, the Internet based communication has widen the opportunity of event monitoring system in the medical field. There is always a need of analyzing and designing secure and reliable mobile communication between the hospital and biomedical engineers mobile units. This study has been carried out to find possible solution using SIP-based event notification for alerting the technical staff about the Biomedical Device (BMD) status and Patients treatment session. The Session Initiation Protocol (SIP) can be used to create a medical event notification system. SIP can work on a variety of devices. Its adoption as the protocol of choice for third generation wireless networks allows for a robust and scalable environment. One of the advantages of SIP is that it supports personal mobility through the separation of user addressing and device addressing. The solution for Telemed alert notification system is based on SIP - Specific Event Notification. The aim of this project is to extend mobility service to the hospital technicians who are using Telemedicine system.Keywords: Biomedical, Mobility Service, Notify, Proxy Server, SIP, Subscribe, Telemedicine.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18011625 Fuzzy based Security Threshold Determining for the Statistical En-Route Filtering in Sensor Networks
Authors: Hae Young Lee, Tae Ho Cho
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In many sensor network applications, sensor nodes are deployed in open environments, and hence are vulnerable to physical attacks, potentially compromising the node's cryptographic keys. False sensing report can be injected through compromised nodes, which can lead to not only false alarms but also the depletion of limited energy resource in battery powered networks. Ye et al. proposed a statistical en-route filtering scheme (SEF) to detect such false reports during the forwarding process. In this scheme, the choice of a security threshold value is important since it trades off detection power and overhead. In this paper, we propose a fuzzy logic for determining a security threshold value in the SEF based sensor networks. The fuzzy logic determines a security threshold by considering the number of partitions in a global key pool, the number of compromised partitions, and the energy level of nodes. The fuzzy based threshold value can conserve energy, while it provides sufficient detection power.
Keywords: Fuzzy logic, security, sensor network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15821624 Integrated Mass Rapid Transit System for Smart City Project in Western India
Authors: Debasis Sarkar, Jatan Talati
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This paper is an attempt to develop an Integrated Mass Rapid Transit System (MRTS) for a smart city project in Western India. Integrated transportation is one of the enablers of smart transportation for providing a seamless intercity as well as regional level transportation experience. The success of a smart city project at the city level for transportation is providing proper integration to different mass rapid transit modes by way of integrating information, physical, network of routes fares, etc. The methodology adopted for this study was primary data research through questionnaire survey. The respondents of the questionnaire survey have responded on the issues about their perceptions on the ways and means to improve public transport services in urban cities. The respondents were also required to identify the factors and attributes which might motivate more people to shift towards the public mode. Also, the respondents were questioned about the factors which they feel might restrain the integration of various modes of MRTS. Furthermore, this study also focuses on developing a utility equation for respondents with the help of multiple linear regression analysis and its probability to shift to public transport for certain factors listed in the questionnaire. It has been observed that for shifting to public transport, the most important factors that need to be considered were travel time saving and comfort rating. Also, an Integrated MRTS can be obtained by combining metro rail with BRTS, metro rail with monorail, monorail with BRTS and metro rail with Indian railways. Providing a common smart card to transport users for accessing all the different available modes would be a pragmatic solution towards integration of the available modes of MRTS.
Keywords: Mass rapid transit systems, smart city, metro rail, bus rapid transit system, multiple linear regression, smart card, automated fare collection system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12281623 Supplier Sift – A Strategic Need of Modern Entrepreneurship
Authors: Rizwan Moeen, Riaz Ahmad, Tanweer Ul Islam, Shahid Ikramullah, Muhammad Umer
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Supplier appraisal fosters energy in Supply Chain Management and helps in best optimization of viable business partners for a company. Many Decision Making techniques have already been proposed by researchers for supplier-s appraisal. However, Analytic Hierarchy Process (AHP) is assumed to be the most structured technique to attain near-best solution of the problem. This paper focuses at implementation of AHP in the procurement processes. It also suggests that on what factors a Public Sector Enterprises must focus while dealing with their suppliers and what should the suppliers do to synchronize their activities with the strategic objectives of Organization. It also highlights the weak areas in supplier appraisal process with a view to suggest viable recommendations.Keywords: AHP, MCDM techniques, Supply Chain Management (SCM), Supplier appraisal.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22911622 Evaluating the Use of Digital Art Tools for Drawing to Enhance Artistic Ability and Improve Digital Skill among Junior School Students
Authors: Aber S. Aboalgasm, Rupert Ward
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This study investigated some results of the use of digital art tools by junior school children in order to discover if these tools could promote artistic ability and creativity. The study considers the ease of use and usefulness of the tools as well as how to assess artwork produced by digital means. As the use of these tools is a relatively new development in Art education, this study may help educators in their choice of which tools to use and when to use them. The study also aims to present a model for the assessment of students’ artistic development and creativity by studying their artistic activity. This model can help in determining differences in students’ creative ability and could be useful both for teachers, as a means of assessing digital artwork, and for students, by providing the motivation to use the tools to their fullest extent. Sixteen students aged nine to ten years old were observed and recorded while they used the digital drawing tools. The study found that, according to the students’ own statements, it was not the ease of use but the successful effects the tools provided which motivated the children to use them.
Keywords: Artistic ability, creativity, drawing digital tool, TAM model, psychomotor domain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28171621 Multi-level Metadata Integration System: XML, RDF and RuleML
Authors: Messaouda Fareh, Omar Boussaid, Rachid Challal
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Our work is part of the heterogeneous data integration, with the definition of a structural and semantic mediation model. Our aim is to propose architecture for the heterogeneous sources metadata mediation, represented by XML, RDF and RuleML models, providing to the user the metadata transparency. This, by including data structures, of natures fundamentally different, and allowing the decomposition of a query involving multiple sources, to queries specific to these sources, then recompose the result.Keywords: Mediator, Metadata, Query, RDF, RuleML, XML, Xquery.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17201620 Gender Differences in the Perception of Advertising in Postmodern Era
Authors: J. Zavodny Pospisil, L. S. Zavodna, K. Cerna
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The goal of this paper is to identify the main differences in the way men and women perceive TV ads. This paper is based on a research project conducted partly as a review of relevant papers, which deals with gender influence on the cognitive process and postmodern perception of advertising. In addition to that, qualitative research was conducted by means of interviews and structured questionnaires. Furthermore, data acquired from the research were used to evaluate our objectives and hypotheses. The goal of this paper is to compare women's and men's perception of advertisement. Although women are able to perceive more details than men, men are more susceptible to sexual appeals in advertising. Significant differences were also found in the perception of sexual appeals in the context of gender.Keywords: Advertising, consumer, emotion, gender, psychology of advertising.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25071619 The Impacts of Cost Stickiness on the Profitability of Indonesian Firms
Authors: Dezie L. Warganegara, Dewi Tamara
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The objectives of this study is to investigate the existence of the sticky cost behavior of firms listed in the Indonesia Stock Exchange (IDX) and to find evidence on the effects of sticky operating expenses (SG&A expenses) on profitability of firms. For the first objective, this study finds that the sticky cost behavior does exist. For the second objective, this study finds that the stickier the operating expenses the lesser future profitability of the firms. This study concludes that sticky cost affects negatively to the performance and, therefore, firms should include flexibility in designing the cost structure of their firms.
Keywords: Operating Expenses, Profitability, SG&A, Sticky Costs, Indonesia Stock Exchange (IDX).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 34671618 A Study of Students’ Perceptions Regarding the Effectiveness of Semester and Annual Examination System at Institute of Education and Research
Authors: Ayesha Batool, Saghir Ahmad, Abid Hussain Ch.
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The art of the examination is probably the most difficult one in the whole range of educational practices. Semester system is the system of examination, which is set with an institute by its own teachers. Annual system is the system of examination, which is constructed and administrated by some agency outside the institute, it enables the teacher to estimate the effectiveness of the instruction, and students to estimate the progress made by them. On the other hand, semester system of examinations requires following the curriculum strictly and methods of teaching are to be employed by the choice of teachers. The main purpose of the study was to investigate university students’ perceptions regarding the effectiveness of semester system and annual system. The study was quantitative in nature. The sample consisted of 200 students. A five point Likert type scale was used to collect the data. The statistical measures like frequencies, mean, standard deviation, and One Way ANOVA test were applied to analyze the data. The major findings of the study indicated that in semester system students do not spend much time in political activities and develop their study habits. It also revealed that annual system of examination does not satisfy the educational aspirations of the students.
Keywords: Effectiveness, semester system, annual system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9421617 Hopf Bifurcation Analysis for a Delayed Predator–prey System with Stage Structure
Authors: Kejun Zhuang
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In this paper, a delayed predator–prey system with stage structure is investigated. Sufficient conditions for the system to have multiple periodic solutions are obtained when the delay is sufficiently large by applying Bendixson-s criterion. Further, some numerical examples are given.Keywords: Predator-prey system, Stage structure, Hopf bifurcation, Periodic solutions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13311616 The Removal of Cu (II) Ions from Aqueous Solutions on Synthetic Zeolite NaA
Authors: Dimitar Georgiev, Bogdan Bogdanov, Yancho Hristov, Irena Markovska
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In this study the adsorption of Cu (II) ions from aqueous solutions on synthetic zeolite NaA was evaluated. The effect of solution temperature and the determination of the kinetic parameters of adsorption of Cu(II) from aqueous solution on zeolite NaA is important in understanding the adsorption mechanism. Variables of the system include adsorption time, temperature (293- 328K), initial solution concentration and pH for the system. The sorption kinetics of the copper ions were found to be strongly dependent on pH (the optimum pH 3-5), solute ion concentration and temperature (293 – 328 K). It was found, the pseudo-second-order model was the best choice among all the kinetic models to describe the adsorption behavior of Cu(II) onto ziolite NaA, suggesting that the adsorption mechanism might be a chemisorptions process The activation energy of adsorption (Ea) was determined as Cu(II) 13.5 kJ mol-1. The low value of Ea shows that Cu(II) adsorption process by zeolite NaA may be an activated chemical adsorption. The thermodynamic parameters (ΔG0, ΔH0, and ΔS0) were also determined from the temperature dependence. The results show that the process of adsorption Cu(II) is spontaneous and endothermic process and rise in temperature favors the adsorption.
Keywords: Zeolite NaA, adsorption, adsorption capacity, kinetic sorption
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22091615 Some Aspects of the Sustainable Development in Romania
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The paper presents the Romanian realities and perspectives from the point of view of reaching the sustainable development model in the context of the recent accession to the European Union, based on the analysis of the indicators listed in the EU Sustainable Development Strategy. The analysis of the economic-social potential for sustainable development and of the environment aspects show that the objectives stipulated in the renewed EU Sustainable Development Strategy of 2006 can be reached, but an extra effort must be put-in in order to overcome the existing substantial gaps in several areas in relation to the developed countries of the EU. The paper-s conclusions show that even if sustainable development is not an easy target to reach in Romania, there are resources and a growing potential, which can lead to sustainable development if used rationally.
Keywords: Ecological dimension, economic-social potential, strategy, sustainable development
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20601614 Internal and External Influences on the Firm Objective
Authors: A. Briseno, A, Zorrilla
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Firms are increasingly responding to social and environmental claims from society. Practices oriented to attend issues such as poverty, work equality, or renewable energy, are being implemented more frequently by firms to address impacts on sustainability. However, questions remain on how the responses of firms vary across industries and regions between the social and the economic objectives. Using concepts from organizational theory and social network theory, this paper aims to create a theoretical framework that explains the internal and external influences that make a firm establish its objective. The framework explains why firms might have a different objective orientation in terms of its economic and social prioritization.Keywords: Organizational identity, social network analysis, firm objective, value maximization, social responsibility.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9291613 Modeling Methodologies for Optimization and Decision Support on Coastal Transport Information System (Co.Tr.I.S.)
Authors: Vassilios Moussas, Dimos N. Pantazis, Panagiotis Stratakis
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The aim of this paper is to present the optimization methodology developed in the frame of a Coastal Transport Information System. The system will be used for the effective design of coastal transportation lines and incorporates subsystems that implement models, tools and techniques that may support the design of improved networks. The role of the optimization and decision subsystem is to provide the user with better and optimal scenarios that will best fulfill any constrains, goals or requirements posed. The complexity of the problem and the large number of parameters and objectives involved led to the adoption of an evolutionary method (Genetic Algorithms). The problem model and the subsystem structure are presented in detail, and, its support for simulation is also discussed.
Keywords: Coastal transport, modeling, optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20051612 Endogenous Fantasy – Based Serious Games: Intrinsic Motivation and Learning
Authors: Robert F. Kenny, Glenda A. Gunter
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Current technological advances pale in comparison to the changes in social behaviors and 'sense of place' that is being empowered since the Internet made it on the scene. Today-s students view the Internet as both a source of entertainment and an educational tool. The development of virtual environments is a conceptual framework that needs to be addressed by educators and it is important that they become familiar with who these virtual learners are and how they are motivated to learn. Massively multiplayer online role playing games (MMORPGs), if well designed, could become the vehicle of choice to deliver learning content. We suggest that these games, in order to accomplish these goals, must begin with well-established instructional design principles that are co-aligned with established principles of video game design. And have the opportunity to provide an instructional model of significant prescriptive power. The authors believe that game designers need to take advantage of the natural motivation player-learners have for playing games by developing them in such a way so as to promote, intrinsic motivation, content learning, transfer of knowledge, and naturalization.
Keywords: serious games, endogenous fantasy, intrinsic motivation, online learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22381611 Simulink Library for Reference Current Generation in Active DC Traction Substations
Authors: Mihaela Popescu, Alexandru Bitoleanu
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This paper is focused on the reference current calculation in the compensation mode of the active DC traction substations. The so-called p-q theory of the instantaneous reactive power is used as theoretical foundation. The compensation goal of total compensation is taken into consideration for the operation under both sinusoidal and nonsinusoidal voltage conditions, through the two objectives of unity power factor and perfect harmonic cancelation. Four blocks of reference current generation implement the conceived algorithms and they are included in a specific Simulink library, which is useful in a DSP dSPACE-based platform working under Matlab/Simulink. The simulation results validate the correctness of the implementation and fulfillment of the compensation tasks.Keywords: Active power filter, DC traction, p-q theory, Simulink library.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17451610 Performance Assessment of Carrier Aggregation-Based Indoor Mobile Networks
Authors: Viktor R. Stoynov, Zlatka V. Valkova-Jarvis
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The intelligent management and optimisation of radio resource technologies will lead to a considerable improvement in the overall performance in Next Generation Networks (NGNs). Carrier Aggregation (CA) technology, also known as Spectrum Aggregation, enables more efficient use of the available spectrum by combining multiple Component Carriers (CCs) in a virtual wideband channel. LTE-A (Long Term Evolution–Advanced) CA technology can combine multiple adjacent or separate CCs in the same band or in different bands. In this way, increased data rates and dynamic load balancing can be achieved, resulting in a more reliable and efficient operation of mobile networks and the enabling of high bandwidth mobile services. In this paper, several distinct CA deployment strategies for the utilisation of spectrum bands are compared in indoor-outdoor scenarios, simulated via the recently-developed Realistic Indoor Environment Generator (RIEG). We analyse the performance of the User Equipment (UE) by integrating the average throughput, the level of fairness of radio resource allocation, and other parameters, into one summative assessment termed a Comparative Factor (CF). In addition, comparison of non-CA and CA indoor mobile networks is carried out under different load conditions: varying numbers and positions of UEs. The experimental results demonstrate that the CA technology can improve network performance, especially in the case of indoor scenarios. Additionally, we show that an increase of carrier frequency does not necessarily lead to improved CF values, due to high wall-penetration losses. The performance of users under bad-channel conditions, often located in the periphery of the cells, can be improved by intelligent CA location. Furthermore, a combination of such a deployment and effective radio resource allocation management with respect to user-fairness plays a crucial role in improving the performance of LTE-A networks.
Keywords: Comparative factor, carrier aggregation, indoor mobile network, resource allocation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7151609 Internal Migration and Poverty Dynamic Analysis Using a Bayesian Approach: The Tunisian Case
Authors: Amal Jmaii, Damien Rousseliere, Besma Belhadj
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We explore the relationship between internal migration and poverty in Tunisia. We present a methodology combining potential outcomes approach with multiple imputation to highlight the effect of internal migration on poverty states. We find that probability of being poor decreases when leaving the poorest regions (the west areas) to the richer regions (greater Tunis and the east regions).Keywords: Internal migration, Bayesian approach, poverty dynamics, Tunisia.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9351608 Automatic Extraction of Features and Opinion-Oriented Sentences from Customer Reviews
Authors: Khairullah Khan, Baharum B. Baharudin, Aurangzeb Khan, Fazal_e_Malik
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Opinion extraction about products from customer reviews is becoming an interesting area of research. Customer reviews about products are nowadays available from blogs and review sites. Also tools are being developed for extraction of opinion from these reviews to help the user as well merchants to track the most suitable choice of product. Therefore efficient method and techniques are needed to extract opinions from review and blogs. As reviews of products mostly contains discussion about the features, functions and services, therefore, efficient techniques are required to extract user comments about the desired features, functions and services. In this paper we have proposed a novel idea to find features of product from user review in an efficient way. Our focus in this paper is to get the features and opinion-oriented words about products from text through auxiliary verbs (AV) {is, was, are, were, has, have, had}. From the results of our experiments we found that 82% of features and 85% of opinion-oriented sentences include AVs. Thus these AVs are good indicators of features and opinion orientation in customer reviews.Keywords: Classification, Customer Reviews, Helping Verbs, Opinion Mining.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20981607 Single Ion Transport with a Single-Layer Graphene Nanopore
Authors: Vishal V. R. Nandigana, Mohammad Heiranian, Narayana R. Aluru
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Graphene material has found tremendous applications in water desalination, DNA sequencing and energy storage. Multiple nanopores are etched to create opening for water desalination and energy storage applications. The nanopores created are of the order of 3-5 nm allowing multiple ions to transport through the pore. In this paper, we present for the first time, molecular dynamics study of single ion transport, where only one ion passes through the graphene nanopore. The diameter of the graphene nanopore is of the same order as the hydration layers formed around each ion. Analogous to single electron transport resulting from ionic transport is observed for the first time. The current-voltage characteristics of such a device are similar to single electron transport in quantum dots. The current is blocked until a critical voltage, as the ions are trapped inside a hydration shell. The trapped ions have a high energy barrier compared to the applied input electrical voltage, preventing the ion to break free from the hydration shell. This region is called “Coulomb blockade region”. In this region, we observe zero transport of ions inside the nanopore. However, when the electrical voltage is beyond the critical voltage, the ion has sufficient energy to break free from the energy barrier created by the hydration shell to enter into the pore. Thus, the input voltage can control the transport of the ion inside the nanopore. The device therefore acts as a binary storage unit, storing 0 when no ion passes through the pore and storing 1 when a single ion passes through the pore. We therefore postulate that the device can be used for fluidic computing applications in chemistry and biology, mimicking a computer. Furthermore, the trapped ion stores a finite charge in the Coulomb blockade region; hence the device also acts a super capacitor.Keywords: Graphene, single ion transport, Coulomb blockade, fluidic computer, super capacitor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7241606 Opto-Mechanical Characterization of Aspheric Lenses from the Hybrid Method
Authors: Aliouane Toufik, Hamdi Amine, Bouzid Djamel
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Aspheric optical components are an alternative to the use of conventional lenses in the implementation of imaging systems for the visible range. Spherical lenses are capable of producing aberrations. Therefore, they are not able to focus all the light into a single point. Instead, aspherical lenses correct aberrations and provide better resolution even with compact lenses incorporating a small number of lenses.
Metrology of these components is very difficult especially when the resolution requirements increase and insufficient or complexity of conventional tools requires the development of specific approaches to characterization.
This work is part of the problem existed because the objectives are the study and comparison of different methods used to measure surface rays hybrid aspherical lenses.
Keywords: Aspherical surface, Manufacture of lenses, precision molding, radius of curvature, roughness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2015