Search results for: path independence number
9859 A Hybrid Recommendation System Based on Association Rules
Authors: Ahmed Mohammed Alsalama
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Recommendation systems are widely used in e-commerce applications. The engine of a current recommendation system recommends items to a particular user based on user preferences and previous high ratings. Various recommendation schemes such as collaborative filtering and content-based approaches are used to build a recommendation system. Most of the current recommendation systems were developed to fit a certain domain such as books, articles, and movies. We propose a hybrid framework recommendation system to be applied on two-dimensional spaces (User x Item) with a large number of Users and a small number of Items. Moreover, our proposed framework makes use of both favorite and non-favorite items of a particular user. The proposed framework is built upon the integration of association rules mining and the content-based approach. The results of experiments show that our proposed framework can provide accurate recommendations to users.Keywords: data mining, association rules, recommendation systems, hybrid systems
Procedia PDF Downloads 4539858 Determination of Physical Properties of Crude Oil Distillates by Near-Infrared Spectroscopy and Multivariate Calibration
Authors: Ayten Ekin Meşe, Selahattin Şentürk, Melike Duvanoğlu
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Petroleum refineries are a highly complex process industry with continuous production and high operating costs. Physical separation of crude oil starts with the crude oil distillation unit, continues with various conversion and purification units, and passes through many stages until obtaining the final product. To meet the desired product specification, process parameters are strictly followed. To be able to ensure the quality of distillates, routine analyses are performed in quality control laboratories based on appropriate international standards such as American Society for Testing and Materials (ASTM) standard methods and European Standard (EN) methods. The cut point of distillates in the crude distillation unit is very crucial for the efficiency of the upcoming processes. In order to maximize the process efficiency, the determination of the quality of distillates should be as fast as possible, reliable, and cost-effective. In this sense, an alternative study was carried out on the crude oil distillation unit that serves the entire refinery process. In this work, studies were conducted with three different crude oil distillates which are Light Straight Run Naphtha (LSRN), Heavy Straight Run Naphtha (HSRN), and Kerosene. These products are named after separation by the number of carbons it contains. LSRN consists of five to six carbon-containing hydrocarbons, HSRN consist of six to ten, and kerosene consists of sixteen to twenty-two carbon-containing hydrocarbons. Physical properties of three different crude distillation unit products (LSRN, HSRN, and Kerosene) were determined using Near-Infrared Spectroscopy with multivariate calibration. The absorbance spectra of the petroleum samples were obtained in the range from 10000 cm⁻¹ to 4000 cm⁻¹, employing a quartz transmittance flow through cell with a 2 mm light path and a resolution of 2 cm⁻¹. A total of 400 samples were collected for each petroleum sample for almost four years. Several different crude oil grades were processed during sample collection times. Extended Multiplicative Signal Correction (EMSC) and Savitzky-Golay (SG) preprocessing techniques were applied to FT-NIR spectra of samples to eliminate baseline shifts and suppress unwanted variation. Two different multivariate calibration approaches (Partial Least Squares Regression, PLS and Genetic Inverse Least Squares, GILS) and an ensemble model were applied to preprocessed FT-NIR spectra. Predictive performance of each multivariate calibration technique and preprocessing techniques were compared, and the best models were chosen according to the reproducibility of ASTM reference methods. This work demonstrates the developed models can be used for routine analysis instead of conventional analytical methods with over 90% accuracy.Keywords: crude distillation unit, multivariate calibration, near infrared spectroscopy, data preprocessing, refinery
Procedia PDF Downloads 1319857 The Study of Sensory Breadth Experiences in an Online Try-On Environment
Authors: Tseng-Lung Huang
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Sensory breadth experiences, such as visualization, a sense of self-location, and haptic experiences, are critical in an online try-on environment. This research adopts an emotional appeal perspective, including concrete and abstract effects, to clarify the relationship between sensory experience and consumer's behavior intention in an online try-on context. This study employed an augmented reality interactive technology (ARIT) in an online clothes-fitting context and applied snowball sampling using e-mail to invite online consumers, first to use ARIT for trying on online apparel and then to complete a questionnaire. One hundred sixty-eight valid questionnaires were collected, and partial least squares (PLS) path modeling was used to test our hypotheses. The results showed that sensory breadth, by arousing concrete effect, induces impulse buying intention and willingness to pay a price premium of online shopping. Parasocial presence, as an abstract effect, diminishes the effect of concrete effects on willingness to pay a price premium.Keywords: sensory breadth, impulsive behavior, price premium, emotional appeal, online try-on context
Procedia PDF Downloads 5489856 Expounding the Evolution of the Proto-Femme Fatale and Its Correlation with the New Woman: A Close Study of David Mamet's Oleanna
Authors: Silvia Elias
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The 'Femme Fatale' figure has become synonymous with a mysterious and seductive woman whose charms captivate her lovers into bonds of irresistible desire, often leading them to compromise or downfall. Originally, a Femme Fatale typically uses her beauty to lead men to their destruction but in modern literature, she represents a direct attack on traditional womanhood and the nuclear family as she refuses to abide by the pillars of mainstream society creating an image of a strong independent woman who defies the control of men and rejects the institution of the family. This research aims at discussing the differences and similarities between the femme fatale and the New Woman and how they are perceived by the audience. There is often confusion between the characteristics that define a New Woman and a Femme Fatale since both women desire independence, challenge typical gender role casting, push against the limits of the patriarchal society and take control of their sexuality. The study of the femme fatale remains appealing in modern times because the fear of gender equality gives life to modern femme fatale versions and post-modern literary works introduce their readers to new versions of the deadly seductress. One that does not fully depend on her looks to destroy men. The idea behind writing this paper was born from reading David Mamet's two-character play Oleanna (1992) and tracing the main female protagonist/antagonist's transformation from a helpless inarticulate girl into a powerful controlling negotiator who knows how to lead a bargain and maintain the upper hand.Keywords: Circe, David, Eve, evolution, feminist, femme fatale, gender, Mamet, new, Odysseus, Oleanna, power, Salome, schema, seduction, temptress, woman
Procedia PDF Downloads 4569855 Experimental and Numerical Investigation of Fluid Flow inside Concentric Heat Exchanger Using Different Inlet Geometry Configurations
Authors: Mohamed M. Abo Elazm, Ali I. Shehata, Mohamed M. Khairat Dawood
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A computational fluid dynamics (CFD) program FLUENT has been used to predict the fluid flow and heat transfer distribution within concentric heat exchangers. The effect of inlet inclination angle has been investigated with Reynolds number range (3000 – 4000) and Pr=0.71. The heat exchanger is fabricated from copper concentric inner tube with a length of 750 mm. The effects of hot to cold inlet flow rate ratio (MH/MC), Reynolds's number and of inlet inclination angle of 30°, 45°, 60° and 90° are considered. The results showed that the numerical prediction shows a good agreement with experimental measurement. The results present an efficient design of concentric tube heat exchanger to enhance the heat transfer by increasing the swirling effect.Keywords: heat transfer, swirling effect, CFD, inclination angle, concentric tube heat exchange
Procedia PDF Downloads 3219854 Numerical Investigation on the Interior Wind Noise of a Passenger Car
Authors: Liu Ying-jie, Lu Wen-bo, Peng Cheng-jian
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With the development of the automotive technology and electric vehicle, the contribution of the wind noise on the interior noise becomes the main source of noise. The main transfer path which the exterior excitation is transmitted through is the greenhouse panels and side windows. Simulating the wind noise transmitted into the vehicle accurately in the early development stage can be very challenging. The basic methodologies of this study were based on the Lighthill analogy; the exterior flow field around a passenger car was computed using unsteady Computational Fluid Dynamics (CFD) firstly and then a Finite Element Method (FEM) was used to compute the interior acoustic response. The major findings of this study include: 1) The Sound Pressure Level (SPL) response at driver’s ear locations is mainly induced by the turbulence pressure fluctuation; 2) Peaks were found over the full frequency range. It is found that the methodology used in this study could predict the interior wind noise induced by the exterior aerodynamic excitation in industry.Keywords: wind noise, computational fluid dynamics, finite element method, passenger car
Procedia PDF Downloads 1719853 Mitigation of Electromagnetic Interference Generated by GPIB Control-Network in AC-DC Transfer Measurement System
Authors: M. M. Hlakola, E. Golovins, D. V. Nicolae
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The field of instrumentation electronics is undergoing an explosive growth, due to its wide range of applications. The proliferation of electrical devices in a close working proximity can negatively influence each other’s performance. The degradation in the performance is due to electromagnetic interference (EMI). This paper investigates the negative effects of electromagnetic interference originating in the General Purpose Interface Bus (GPIB) control-network of the ac-dc transfer measurement system. Remedial measures of reducing measurement errors and failure of range of industrial devices due to EMI have been explored. The ac-dc transfer measurement system was analyzed for the common-mode (CM) EMI effects. Further investigation of coupling path as well as more accurate identification of noise propagation mechanism has been outlined. To prevent the occurrence of common-mode (ground loops) which was identified between the GPIB system control circuit and the measurement circuit, a microcontroller-driven GPIB switching isolator device was designed, prototyped, programmed and validated. This mitigation technique has been explored to reduce EMI effectively.Keywords: CM, EMI, GPIB, ground loops
Procedia PDF Downloads 2889852 Investigating the Dynamics of Knowledge Acquisition in Undergraduate Mathematics Students Using Differential Equations
Authors: Gilbert Makanda
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The problem of the teaching of mathematics is studied using differential equations. A mathematical model for knowledge acquisition in mathematics is developed. In this study we adopt the mathematical model that is normally used for disease modelling in the teaching of mathematics. It is assumed that teaching is 'infecting' students with knowledge thereby spreading this knowledge to the students. It is also assumed that students who gain this knowledge spread it to other students making disease model appropriate to adopt for this problem. The results of this study show that increasing recruitment rates, learning contact with teachers and learning materials improves the number of knowledgeable students. High dropout rates and forgetting taught concepts also negatively affect the number of knowledgeable students. The developed model is then solved using Matlab ODE45 and \verb"lsqnonlin" to estimate parameters for the actual data.Keywords: differential equations, knowledge acquisition, least squares, dynamical systems
Procedia PDF Downloads 4239851 Using the Technology Acceptance Model to Examine Seniors’ Attitudes toward Facebook
Authors: Chien-Jen Liu, Shu Ching Yang
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Using the technology acceptance model (TAM), this study examined the external variables of technological complexity (TC) to acquire a better understanding of the factors that influence the acceptance of computer application courses by learners at Active Aging Universities. After the learners in this study had completed a 27-hour Facebook course, 44 learners responded to a modified TAM survey. Data were collected to examine the path relationships among the variables that influence the acceptance of Facebook-mediated community learning. The partial least squares (PLS) method was used to test the measurement and the structural model. The study results demonstrated that attitudes toward Facebook use directly influence behavioral intentions (BI) with respect to Facebook use, evincing a high prediction rate of 58.3%. In addition to the perceived usefulness (PU) and perceived ease of use (PEOU) measures that are proposed in the TAM, other external variables, such as TC, also indirectly influence BI. These four variables can explain 88% of the variance in BI and demonstrate a high level of predictive ability. Finally, limitations of this investigation and implications for further research are discussed.Keywords: technology acceptance model (TAM), technological complexity, partial least squares (PLS), perceived usefulness
Procedia PDF Downloads 3469850 Investigating Elastica and Post Buckling Behavior Columns Using the Modified Newmark Method
Authors: Seyed Amin Vakili, Sahar Sadat Vakili, Seyed Ehsan Vakili, Nader Abdoli Yazdi
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The purpose of this article is to analyze the finite displacement of Columns by applying the Modified Newmark Method. This research will be performed on Columns subjected to compressive axial load, therefore the non-linearity of the geometry is also considered. If the considered strut is perfect, the governing differential equation contains a branching point in the solution path. Investigation into the Elastica is a part of generalizing the developed method. It presents the ability of the Modified Newmark Method in treating non-linear differential equations Derived from elastic strut stability problems. These include not only an approximate polynomial solution for the Elastica problems, but can also recognize the branching point and the stable solution. However, this investigation deals with the post-buckling response of elastic and pin ended columns subjected to central or equally eccentric axial loads.Keywords: columns, structural modeling, structures & structural stability, loads
Procedia PDF Downloads 3149849 Examination of Public Hospital Unions Technical Efficiencies Using Data Envelopment Analysis and Machine Learning Techniques
Authors: Songul Cinaroglu
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Regional planning in health has gained speed for developing countries in recent years. In Turkey, 89 different Public Hospital Unions (PHUs) were conducted based on provincial levels. In this study technical efficiencies of 89 PHUs were examined by using Data Envelopment Analysis (DEA) and machine learning techniques by dividing them into two clusters in terms of similarities of input and output indicators. Number of beds, physicians and nurses determined as input variables and number of outpatients, inpatients and surgical operations determined as output indicators. Before performing DEA, PHUs were grouped into two clusters. It is seen that the first cluster represents PHUs which have higher population, demand and service density than the others. The difference between clusters was statistically significant in terms of all study variables (p ˂ 0.001). After clustering, DEA was performed for general and for two clusters separately. It was found that 11% of PHUs were efficient in general, additionally 21% and 17% of them were efficient for the first and second clusters respectively. It is seen that PHUs, which are representing urban parts of the country and have higher population and service density, are more efficient than others. Random forest decision tree graph shows that number of inpatients is a determinative factor of efficiency of PHUs, which is a measure of service density. It is advisable for public health policy makers to use statistical learning methods in resource planning decisions to improve efficiency in health care.Keywords: public hospital unions, efficiency, data envelopment analysis, random forest
Procedia PDF Downloads 1269848 Analyses of Reference Evapotranspiration in West of Iran under Climate Change
Authors: Saeed Jahanbakhsh Asl, Yaghob Dinpazhoh, Masoumeh Foroughi
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Reference evapotranspiration (ET₀) is an important element in the water cycle that integrates atmospheric demands and surface conditions, and analysis of changes in ET₀ is of great significance for understanding climate change and its impacts on hydrology. As ET₀ is an integrated effect of climate variables, increases in air temperature should lead to increases in ET₀. ET₀ estimated by using the globally accepted Food and Agriculture Organization (FAO) Penman-Monteith (FAO-56 PM) method in 18 meteorological stations located in the West of Iran. The trends of ET₀ detected by using the Mann-Kendall (MK) test. The slopes of the trend lines were computed by using the Sen’s slope estimator. The results showed significant increasing as well as decreasing trends in the annual and monthly ET₀. However, ET₀ trends were increasing. In the monthly scale, the number of the increasing trends was more than the number of decreasing trends, in the majority of warm months of the year.Keywords: climate change, Mann–Kendall, Penman-Monteith method (FAO-56 PM), reference crop evapotranspiration
Procedia PDF Downloads 2899847 The Effects of Rumah Panggung Environment, Social Culture, and Behavior on Malaria Incidence in Kori Village, Indonesia
Authors: Sri Ratna Rahayu, Oktia Woro Kasmini Handayani, Lourensiana Y. S. Ngaga, Imade Sudana, Irwan Budiono
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Malaria is an infectious disease that still cannot be solved in Kori village, West Nusa Tenggara, Indonesia, where the most of people live in rumah panggung (Stilts House). The purpose of this study was to know whether there were the effects of rumah panggung environment, social culture, and behavior on malaria incidence in the Kori village. A cross-sectional study was performed to explore the effects of rumah panggung environment, social culture and behavior on malaria incidence. This study recruited 280 respondents, who live in the rumah panggung, permanent residents in Kori village, were age above 17 years old, and suffered from malaria in the past year. The collected data were analyzed with path analysis. The results of this study showed that the environment of rumah panggung and behavior have a direct effect on the incidence of malaria (p < 0.05). It could be concluded that improvement of environmental conditions of rumah panggung, sociocultural, and behavioral changes to maintain a healthy environment are needed to reduce the malaria incidence.Keywords: Rumah panggung, socio-cultural, behavior, Malaria
Procedia PDF Downloads 2299846 Pyramid of Deradicalization: Causes and Possible Solutions
Authors: Ashir Ahmed
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Generally, radicalization happens when a person's thinking and behaviour become significantly different from how most of the members of their society and community view social issues and participate politically. Radicalization often leads to violent extremism that refers to the beliefs and actions of people who support or use violence to achieve ideological, religious or political goals. Studies on radicalization negate the common myths that someone must be in a group to be radicalised or anyone who experiences radical thoughts is a violent extremist. Moreover, it is erroneous to suggest that radicalisation is always linked to religion. Generally, the common motives of radicalization include ideological, issue-based, ethno-nationalist or separatist underpinning. Moreover, there are number of factors that further augments the chances of someone being radicalised and may choose the path of violent extremism and possibly terrorism. Since there are numbers of factors (and sometimes quite different) contributing in radicalization and violent extremism, it is highly unlikely to devise a single solution that could produce effective outcomes to deal with radicalization, violent extremism and terrorism. The pathway to deradicalization, like the pathway to radicalisation, is different for everyone. Considering the need of having customized deradicalization resolution, this study proposes a multi-tier framework, called ‘pyramid of deradicalization’ that first help identifying the stage at which an individual could be on the radicalization pathway and then propose a customize strategy to deal with the respective stage. The first tier (tier 1) addresses broader community and proposes a ‘universal approach’ aiming to offer community-based design and delivery of educational programs to raise awareness and provide general information on possible factors leading to radicalization and their remedies. The second tier focuses on the members of community who are more vulnerable and are disengaged from the rest of the community. This tier proposes a ‘targeted approach’ targeting the vulnerable members of the community through early intervention such as providing anonymous help lines where people feel confident and comfortable in seeking help without fearing the disclosure of their identity. The third tier aims to focus on people having clear evidence of moving toward extremism or getting radicalized. The people falls in this tier are believed to be supported through ‘interventionist approach’. The interventionist approach advocates the community engagement and community-policing, introducing deradicalization programmes to the targeted individuals and looking after their physical and mental health issues. The fourth and the last tier suggests the strategies to deal with people who are actively breaking the law. ‘Enforcement approach’ suggests various approaches such as strong law enforcement, fairness and accuracy in reporting radicalization events, unbiased treatment by law based on gender, race, nationality or religion and strengthen the family connections.It is anticipated that the operationalization of the proposed framework (‘pyramid of deradicalization’) would help in categorising people considering their tendency to become radicalized and then offer an appropriate strategy to make them valuable and peaceful members of the community.Keywords: deradicalization, framework, terrorism, violent extremism
Procedia PDF Downloads 2699845 Personalize E-Learning System Based on Clustering and Sequence Pattern Mining Approach
Authors: H. S. Saini, K. Vijayalakshmi, Rishi Sayal
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Network-based education has been growing rapidly in size and quality. Knowledge clustering becomes more important in personalized information retrieval for web-learning. A personalized-Learning service after the learners’ knowledge has been classified with clustering. Through automatic analysis of learners’ behaviors, their partition with similar data level and interests may be discovered so as to produce learners with contents that best match educational needs for collaborative learning. We present a specific mining tool and a recommender engine that we have integrated in the online learning in order to help the teacher to carry out the whole e-learning process. We propose to use sequential pattern mining algorithms to discover the most used path by the students and from this information can recommend links to the new students automatically meanwhile they browse in the course. We have Developed a specific author tool in order to help the teacher to apply all the data mining process. We tend to report on many experiments with real knowledge so as to indicate the quality of using both clustering and sequential pattern mining algorithms together for discovering personalized e-learning systems.Keywords: e-learning, cluster, personalization, sequence, pattern
Procedia PDF Downloads 4299844 A Study on the Factors Affecting Student Behavior Intention to Attend Robotics Courses at the Primary and Secondary School Levels
Authors: Jingwen Shan
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In order to explore the key factors affecting the robot program learning intention of school students, this study takes the technology acceptance model as the theoretical basis and invites 167 students from Jiading District of Shanghai as the research subjects. In the robot course, the model of school students on their learning behavior is constructed. By verifying the causal path relationship between variables, it is concluded that teachers can enhance students’ perceptual usefulness to robotics courses by enhancing subjective norms, entertainment perception, and reducing technical anxiety, such as focusing on the gradual progress of programming and analyzing learner characteristics. Students can improve perceived ease of use by enhancing self-efficacy. At the same time, robot hardware designers can optimize in terms of entertainment and interactivity, which will directly or indirectly increase the learning intention of the robot course. By changing these factors, the learning behavior of primary and secondary school students can be more sustainable.Keywords: TAM, learning behavior intentions, robot courses, primary and secondary school students
Procedia PDF Downloads 1519843 Ranking Theory-The Paradigm Shift in Statistical Approach to the Issue of Ranking in a Sports League
Authors: E. Gouya Bozorg
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The issue of ranking of sports teams, in particular soccer teams is of primary importance in the professional sports. However, it is still based on classical statistics and models outside of area of mathematics. Rigorous mathematics and then statistics despite the expectation held of them have not been able to effectively engage in the issue of ranking. It is something that requires serious pathology. The purpose of this study is to change the approach to get closer to mathematics proper for using in the ranking. We recommend using theoretical mathematics as a good option because it can hermeneutically obtain the theoretical concepts and criteria needful for the ranking from everyday language of a League. We have proposed a framework that puts the issue of ranking into a new space that we have applied in soccer as a case study. This is an experimental and theoretical study on the issue of ranking in a professional soccer league based on theoretical mathematics, followed by theoretical statistics. First, we showed the theoretical definition of constant number Є = 1.33 or ‘golden number’ of a soccer league. Then, we have defined the ‘efficiency of a team’ by this number and formula of μ = (Pts / (k.Є)) – 1, in which Pts is a point obtained by a team in k number of games played. Moreover, K.Є index has been used to show the theoretical median line in the league table and to compare top teams and bottom teams. Theoretical coefficient of σ= 1 / (1+ (Ptx / Ptxn)) has also been defined that in every match between the teams x, xn, with respect to the ability of a team and the points of both of them Ptx, Ptxn, and it gives a performance point resulting in a special ranking for the League. And it has been useful particularly in evaluating the performance of weaker teams. The current theory has been examined for the statistical data of 4 major European Leagues during the period of 1998-2014. Results of this study showed that the issue of ranking is dependent on appropriate theoretical indicators of a League. These indicators allowed us to find different forms of ranking of teams in a league including the ‘special table’ of a league. Furthermore, on this basis the issue of a record of team has been revised and amended. In addition, the theory of ranking can be used to compare and classify the different leagues and tournaments. Experimental results obtained from archival statistics of major professional leagues in the world in the past two decades have confirmed the theory. This topic introduces a new theory for ranking of a soccer league. Moreover, this theory can be used to compare different leagues and tournaments.Keywords: efficiency of a team, ranking, special table, theoretical mathematic
Procedia PDF Downloads 4189842 Effects of Major and Minor Modes to Emotional Perceptions of 'Happy' and 'Sad' in Piano Music among Students Aged 9-17
Authors: Nurezlin Mohd Azib, Pan Kok Chang
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This quantitative study investigates the effects of major and minor modes, and contributing musical parameter of tempo, to the emotional perceptions of ‘happy’ and ‘sad’ in piano music among subjects aged 9-17 years old. The study was conducted in two phases; survey-questionnaire, and listening activity. Subjects (N=31) were sampled from piano music students’ population in Bangi, Selangor. In the survey-questionnaire, subjects answered 20 questions on demographic characteristics, music listening and preference, and understanding of emotional perception in music. In the listening activity, subjects listened to 20 untitled piano music excerpts and rated the emotion perceived for each excerpt, whether ‘happy’ or ‘sad’. Results from survey-questionnaire show that most percentage of subjects are 11 years old, in Grade 1, of 3 years of learning piano, prefer classical music, always listen to music, prefer both major and minor modes’ music, and find it easy to understand emotion in music, as well as major and minor modes. Results from listening activity show that 60 % of major mode music are perceived as ‘major-happy’, while 60 % too, of minor mode music are perceived as ‘minor-sad’. However, Chi-square test of independence statistical analysis indicates that there are no association and significant relationship between modes (major and minor) and ‘happy’, as well as ‘sad’ perceptions (x2 (1, N = 20) = 0.80, p = 0.371), at the significance level of p ≤ 0.05. Contrastingly, there are association and significant relationship between tempo (fast and slow), and ‘happy’, as well as ‘sad’ perceptions (x2 (1, N = 20) = 9.899, p = 0.005). Therefore, it is concluded that tempo plays an important role in effects of major and minor mode to ‘happy’ and ‘sad’ emotional perceptions in piano music among subjects aged 9 to 17 in this study.Keywords: effects, emotional perceptions, major and minor modes, piano music
Procedia PDF Downloads 2179841 Effect of Bi-Dispersity on Particle Clustering in Sedimentation
Authors: Ali Abbas Zaidi
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In free settling or sedimentation, particles form clusters at high Reynolds number and dilute suspensions. It is due to the entrapment of particles in the wakes of upstream particles. In this paper, the effect of bi-dispersity of settling particles on particle clustering is investigated using particle-resolved direct numerical simulation. Immersed boundary method is used for particle fluid interactions and discrete element method is used for particle-particle interactions. The solid volume fraction used in the simulation is 1% and the Reynolds number based on Sauter mean diameter is 350. Both solid volume fraction and Reynolds number lie in the clustering regime of sedimentation. In simulations, the particle diameter ratio (i.e. diameter of larger particle to smaller particle (d₁/d₂)) is varied from 2:1, 3:1 and 4:1. For each case of particle diameter ratio, solid volume fraction for each particle size (φ₁/φ₂) is varied from 1:1, 1:2 and 2:1. For comparison, simulations are also performed for monodisperse particles. For studying particles clustering, radial distribution function and instantaneous location of particles in the computational domain are studied. It is observed that the degree of particle clustering decreases with the increase in the bi-dispersity of settling particles. The smallest degree of particle clustering or dispersion of particles is observed for particles with d₁/d₂ equal to 4:1 and φ₁/φ₂ equal to 1:2. Simulations showed that the reduction in particle clustering by increasing bi-dispersity is due to the difference in settling velocity of particles. Particles with larger size settle faster and knockout the smaller particles from clustered regions of particles in the computational domain.Keywords: dispersion in bi-disperse settling particles, particle microstructures in bi-disperse suspensions, particle resolved direct numerical simulations, settling of bi-disperse particles
Procedia PDF Downloads 2089840 Teaching Italian Sign Language in Higher Education
Authors: Maria Tagarelli De Monte
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Since its formal recognition in 2021, Italian Sign Language (LIS) and interpreters’ education has become a topic for higher education in Italian universities. In April 2022, Italian universities have been invited to present their proposals to create sign language courses for interpreters’ training for both LIS and tactile LIS. As a result, a few universities have presented a three-year course leading candidate students from the introductory level to interpreters. In such a context, there is an open debate not only on the fact that three years may not be enough to prepare skillful interpreters but also on the need to refer to international standards in the definition of the training path to follow. Among these, are the Common European Framework of Reference (CEFR) for languages and Dublin’s descriptors. This contribution will discuss the potentials and the challenges given by LIS training in academic settings, by comparing traditional studies to the requests coming from universities. Particular attention will be given to the use of CEFR as a reference document for the Italian Sign Language Curriculum. Its use has given me the chance to reflect on how LIS can be taught in higher education, and the adaptations that need to be addressed to respect the visual-gestural nature of sign language and the formal requirements of academic settings.Keywords: Italian sign language, higher education, sign language curriculum, interpreters education, CEFR
Procedia PDF Downloads 459839 Rotary Entrainment in Two Phase Stratified Gas-Liquid Layers: An Experimental Study
Authors: Yagya Sharma, Basanta K. Rana, Arup K. Das
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Rotary entrainment is a phenomenon in which the interfaces of two immiscible fluids are subjected to external flux in the form of rotation. Present work reports the experimental study on rotary motion of a horizontal cylinder between the interface of air and water to observe the penetration of gas inside the liquid. Experiments have been performed to establish entrainment of air mass in water alongside the cylindrical surface. The movement of tracer and seeded particles have been tracked to calculate the speed and path of the entrained air inside water. Simplified particle image velocimetry technique has been used to trace the movement of particles/tracers at the moment they are injected inside the entrainment zone and suspended beads have been used to replicate the particle movement with respect to time in order to determine the flow dynamics of the fluid along the cylinder. Present paper establishes a thorough experimental analysis of the rotary entrainment phenomenon between air and water keeping in interest the extent to which we can intermix the two and also to study its entrainment trajectories.Keywords: entrainment, gas-liquid flow, particle image velocimetry, stratified layer mixing
Procedia PDF Downloads 3399838 A Spiral Dynamic Optimised Hybrid Fuzzy Logic Controller for a Unicycle Mobile Robot on Irregular Terrains
Authors: Abdullah M. Almeshal, Mohammad R. Alenezi, Talal H. Alzanki
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This paper presents a hybrid fuzzy logic control strategy for a unicycle trajectory following robot on irregular terrains. In literature, researchers have presented the design of path tracking controllers of mobile robots on non-frictional surface. In this work, the robot is simulated to drive on irregular terrains with contrasting frictional profiles of peat and rough gravel. A hybrid fuzzy logic controller is utilised to stabilise and drive the robot precisely with the predefined trajectory and overcome the frictional impact. The controller gains and scaling factors were optimised using spiral dynamics optimisation algorithm to minimise the mean square error of the linear and angular velocities of the unicycle robot. The robot was simulated on various frictional surfaces and terrains and the controller was able to stabilise the robot with a superior performance that is shown via simulation results.Keywords: fuzzy logic control, mobile robot, trajectory tracking, spiral dynamic algorithm
Procedia PDF Downloads 4959837 Investigation of Heat Transfer of Nanofluids in Circular Microchannels
Authors: Bayram Sahin, Hourieh Bayramian, Emre Mandev, Murat Ceylan
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In industrial applications, the demand for the enhancement of heat transfer is a common engineering problem. The use of additives to heat transfer fluid is a technique applied to enhance the heat transfer performance of base fluids. In this study, the thermal performance of nanofluids consisting of SiO2 particles and deionized water in circular microchannels was investigated experimentally. SiO2 nanoparticles with diameter of 15 nm were added to water to prepare nanofluids with 0.2% and 0.4% volume fractions. Heat transfer characteristics were calculated by using temperature, flow and pressure measurements. The thermal conductivity and viscosity values required for the calculations are measured separately. It is observed that the Nusselt number increases at the all volume fraction of particles, by increasing the Reynolds number and the volumetric ratios of the particles. The highest heat transfer enhancement is obtained at Re = 2160 and 0.4 % vol. by 14% under the condition of a constant pumping power.Keywords: nanofluid, microchannel, heat transfer, SiO2-water nanofluid
Procedia PDF Downloads 3879836 Mapping a Data Governance Framework to the Continuum of Care in the Active Assisted Living Context
Authors: Gaya Bin Noon, Thoko Hanjahanja-Phiri, Laura Xavier Fadrique, Plinio Pelegrini Morita, Hélène Vaillancourt, Jennifer Teague, Tania Donovska
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Active Assisted Living (AAL) refers to systems designed to improve the quality of life, aid in independence, and create healthier lifestyles for care recipients. As the population ages, there is a pressing need for non-intrusive, continuous, adaptable, and reliable health monitoring tools to support aging in place. AAL has great potential to support these efforts with the wide variety of solutions currently available, but insufficient efforts have been made to address concerns arising from the integration of AAL into care. The purpose of this research was to (1) explore the integration of AAL technologies and data into the clinical pathway, and (2) map data access and governance for AAL technology in order to develop standards for use by policy-makers, technology manufacturers, and developers of smart communities for seniors. This was done through four successive research phases: (1) literature search to explore existing work in this area and identify lessons learned; (2) modeling of the continuum of care; (3) adapting a framework for data governance into the AAL context; and (4) interviews with stakeholders to explore the applicability of previous work. Opportunities for standards found in these research phases included a need for greater consistency in language and technology requirements, better role definition regarding who can access and who is responsible for taking action based on the gathered data, and understanding of the privacy-utility tradeoff inherent in using AAL technologies in care settings.Keywords: active assisted living, aging in place, internet of things, standards
Procedia PDF Downloads 1329835 Runoff Simulation by Using WetSpa Model in Garmabrood Watershed of Mazandaran Province, Iran
Authors: Mohammad Reza Dahmardeh Ghaleno, Mohammad Nohtani, Saeedeh Khaledi
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Hydrological models are applied to simulation and prediction floods in watersheds. WetSpa is a distributed, continuous and physically model with daily or hourly time step that explains of precipitation, runoff and evapotranspiration processes for both simple and complex contexts. This model uses a modified rational method for runoff calculation. In this model, runoff is routed along the flow path using Diffusion-Wave Equation which depend on the slope, velocity and flow route characteristics. Garmabrood watershed located in Mazandaran province in Iran and passing over coordinates 53° 10´ 55" to 53° 38´ 20" E and 36° 06´ 45" to 36° 25´ 30"N. The area of the catchment is about 1133 km2 and elevations in the catchment range from 213 to 3136 m at the outlet, with average slope of 25.77 %. Results of the simulations show a good agreement between calculated and measured hydrographs at the outlet of the basin. Drawing upon Nash-Sutcliffe Model Efficiency Coefficient for calibration periodic model estimated daily hydrographs and maximum flow rate with an accuracy up to 61% and 83.17 % respectively.Keywords: watershed simulation, WetSpa, runoff, flood prediction
Procedia PDF Downloads 3369834 Effects of Essential Oils on the Intestinal Microflora of Termite (Heterotermes indicola)
Authors: Ayesha Aihetasham, Najma Arshad, Sobia Khan
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Damage causes by subterranean termites are of major concern today. Termites majorly treated with pesticides resulted in several problems related to health and environment. For this reason, plant-derived natural products specifically essential oils have been evaluated in order to control termites. The aim of the present study was to investigate the antitermitic potential of six essential oils on Heterotermes indicola subterranean termite. No-choice bioassay was used to assess the termiticidal action of essential oils. Further, gut from each set of treated termite group was extracted and analyzed for reduction in number of protozoa and bacteria by protozoal count method using haemocytometer and viable bacterial plate count (dilution method) respectively. In no-choice bioassay it was found that Foeniculum vulgare oil causes high degree of mortality 90 % average mortality at 10 mg oil concentration (10mg/0.42g weight of filter paper). Least mortality appeared to be due to Citrus sinensis oil (43.33 % average mortality at 10 mg/0.42g). The highest activity verified to be of Foeniculum vulgare followed by Eruca sativa, Trigonella foenum-graecum, Peganum harmala, Syzygium cumini and Citrus sinensis. The essential oil which caused maximum reduction in number of protozoa was P. harmala followed by T. foenum-graecum and E. sativa. In case of bacterial count E. sativa oil indicated maximum decrease in bacterial number (6.4×10⁹ CFU/ml). It is concluded that F. vulgare, E. sativa and P. harmala essential oils are highly effective against H. indicola termite and its gut microflora.Keywords: bacterial count, essential oils, Heterotermes indicola, protozoal count
Procedia PDF Downloads 2479833 Design of S-Shape GPS Application Electrically Small Antenna
Authors: Riki H. Patel, Arpan Desai, Trushit Upadhyaya, Shobhit K. Patel
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The micro strip antennas area has seen some inventive work in recent years and is now one of the most dynamic fields of antenna theory. A novel and simple printed wideband monopole antenna is presented. Printed on a single dielectric substrate and easily fed by using a 50 ohm microstip line, low-profile antenna structure with two parallel S-shaped meandered line of same size. In this research, S–form micro strip patch antenna is designed from measuring the prototypes of the proposed antenna one available bands with 10db return loss bandwidths of about GPS application (GPS L2 1490 MHz) and covering the 1400 to 1580 MHz frequency band at 1.5 GHz The simulated results for main parameters such as return loss, impedance bandwidth, radiation patterns and gains are also discussed herein. The modeling study shows that such antennas, in simplicity design and supply, and can satisfy GPS application. Two parallel slots are incorporated to disturb the surface flow path, introducing local inductive effect. This antenna is fed by a coaxial feeding tube.Keywords: bandwidth, electrically small antenna, microstrip, patch antenna, GPS
Procedia PDF Downloads 4969832 Vulnerable Paths Assessment for Distributed Denial of Service Attacks in a Cloud Computing Environment
Authors: Manas Tripathi, Arunabha Mukhopadhyay
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In Cloud computing environment, cloud servers, sometimes may crash after receiving huge amount of request and cloud services may stop which can create huge loss to users of that cloud services. This situation is called Denial of Service (DoS) attack. In Distributed Denial of Service (DDoS) attack, an attacker targets multiple network paths by compromising various vulnerable systems (zombies) and floods the victim with huge amount of request through these zombies. There are many solutions to mitigate this challenge but most of the methods allows the attack traffic to arrive at Cloud Service Provider (CSP) and then only takes actions against mitigation. Here in this paper we are rather focusing on preventive mechanism to deal with these attacks. We analyze network topology and find most vulnerable paths beforehand without waiting for the traffic to arrive at CSP. We have used Dijkstra's and Yen’s algorithm. Finally, risk assessment of these paths can be done by multiplying the probabilities of attack for these paths with the potential loss.Keywords: cloud computing, DDoS, Dijkstra, Yen’s k-shortest path, network security
Procedia PDF Downloads 2789831 Analysis of Bending Abilities of Soft Pneumatic Actuator
Authors: Jeevan Balaji, Shreyas Chigurupati
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Pneumatic gripper use compressed air to operate its actuators (fingers). Unlike the conventional metallic gripper, a soft pneumatic actuator (SPA) can be used for relocating fragile objects. An added advantage for this gripper is that the pressure exerted on the object can be varied by changing the dimensions of the air chambers and also by the number of chambers. SPAs have many benefits over conventional robots in the military, medical fields because of their compliance nature and are easily produced using the 3D printing process. In the paper, SPA is proposed to perform pick and place tasks. A design was developed for the actuators, which is convenient for gripping any fragile objects. Thermoplastic polyurethane (TPU) is used for 3D printing the actuators. The actuator model behaves differently as the parameters such as its chamber height, number of chambers change. A detailed FEM model of the actuator is drafted for different pressure inputs using ABAQUS CAE software, and a safe loading pressure range is found.Keywords: soft robotics, pneumatic actuator, design and modelling, bending analysis
Procedia PDF Downloads 1669830 Usability Evaluation of a Mobile Application to Enhance the Use of Smartphone, by Visually Impaired Users in Indonesia
Authors: Johanna Renny Octavia, Kamila Okta Saarah
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Smartphone nowadays is widely used by many people all over the world. However, people with vision impairment may experience difficulties that interfere with the proper usage of the smartphone. In Indonesia, the population of visually impaired is about 13 million people (estimated 285 million people worldwide). There are a number of mobile applications developed to enhance the use of smartphone by visually impaired. This paper discusses the usability evaluation of a mobile application, namely Ray Vision, designed to help visually impaired in using smartphone. A series of usability testing with a number of Indonesian visually impaired revealed 28 usability problems in the mobile application that led to 14 design recommendations. The redesigned application was then re-evaluated through another usability testing series. The results showed that all five usability criteria assessed were increased (usefulness by 13%, effectiveness by 27%, efficiency by 27%, satisfaction by 23%, and learnability by 12%). The System Usability Score (SUS) was also increased by 14.92%.Keywords: mobile application, smartphone, usability evaluation, vision impaired
Procedia PDF Downloads 313