Search results for: bagasse paper
14601 LaPEA: Language for Preprocessing of Edge Applications in Smart Factory
Authors: Masaki Sakai, Tsuyoshi Nakajima, Kazuya Takahashi
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In order to improve the productivity of a factory, it is often the case to create an inference model by collecting and analyzing operational data off-line and then to develop an edge application (EAP) that evaluates the quality of the products or diagnoses machine faults in real-time. To accelerate this development cycle, an edge application framework for the smart factory is proposed, which enables to create and modify EAPs based on prepared inference models. In the framework, the preprocessing component is the key part to make it work. This paper proposes a language for preprocessing of edge applications, called LaPEA, which can flexibly process several sensor data from machines into explanatory variables for an inference model, and proves that it meets the requirements for the preprocessing.Keywords: edge application framework, edgecross, preprocessing language, smart factory
Procedia PDF Downloads 12914600 Maximaxing the Usage of Solar Energy in an Area of Low Peak Sunlight Hours
Authors: Ohabuiro John Uwabunkeonye
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Source of green energy is becoming a concern in developing countries where most energy source in use emits high level of carbon (IV) oxide which contributes to global warming. More so, even with the generation of energy from fossil fuel, the electricity supply is still very inadequate. Therefore, this paper examines different ways of designing and installing photovoltaic (PV) system in terms of optimal sizing of PV array and battery storage in an area of very low peak sunlight hours (PSH) and inadequate supply of electricity from utility companies. Different sample of Peak sunlight hour for selected areas in Nigeria are considered and the lowest of it all is taken. Some means of ensuring that the available solar energy is harnessed properly and converted into electrical energy are discussed for usage in such areas as mentioned above.Keywords: green energy, fossil fuel, peak sunlight hour, photovoltaic
Procedia PDF Downloads 63114599 Strategies of Spatial Optimization for Open Space in the Old-Age Friendly City: An Investigation of the Behavior of the Elderly in Xicheng Square in Hangzhou
Authors: Yunxiang Fang
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With the aging trend continuing to accelerate, open space is important for the daily life of the elderly, and its old-age friendliness is worthy of attention. Based on behavioral observation and literature research, this paper studies the behavior of the elderly in urban open space. Through the investigation, classification and quantitative analysis of the activity types, time characteristics and spatial behavior order of the elderly in Xicheng Square in Hangzhou, it summarizes the square space suitable for the psychological needs, physiology and activity needs of the elderly, combined with the basis of literature research. Finally, the suggestions for the improvement of the old-age friendship of Xicheng Square are put forward, from the aspects of microclimate, safety and accessibility, space richness and service facility quality.Keywords: behavior characteristics, old-age friendliness, open space, square
Procedia PDF Downloads 15914598 First Investigation on CZTS Electron affinity and Thickness Optimization using SILVACO-Atlas 2D Simulation
Authors: Zeineb Seboui, Samar Dabbabi
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In this paper, we study the performance of Cu₂ZnSnS₄ (CZTS) based solar cell. In our knowledge, it is for the first time that the FTO/ZnO:Co/CZTS structure is simulated using the SILVACO-Atlas 2D simulation. Cu₂ZnSnS₄ (CZTS), ZnO:Co and FTO (SnO₂:F) layers have been deposited on glass substrates by the spray pyrolysis technique. The extracted physical properties, such as thickness and optical parameters of CZTS layer, are considered to create a new input data of CZTS based solar cell. The optimization of CZTS electron affinity and thickness is performed to have the best FTO/ZnO: Co/CZTS efficiency. The use of CZTS absorber layer with 3.99 eV electron affinity and 3.2 µm in thickness leads to the higher efficiency of 16.86 %, which is very important in the development of new technologies and new solar cell devices.Keywords: CZTS solar cell, characterization, electron affinity, thickness, SILVACO-atlas 2D simulation
Procedia PDF Downloads 6314597 Prediction of the Tunnel Fire Flame Length by Hybrid Model of Neural Network and Genetic Algorithms
Authors: Behzad Niknam, Kourosh Shahriar, Hassan Madani
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This paper demonstrates the applicability of Hybrid Neural Networks that combine with back propagation networks (BPN) and Genetic Algorithms (GAs) for predicting the flame length of tunnel fire A hybrid neural network model has been developed to predict the flame length of tunnel fire based parameters such as Fire Heat Release rate, air velocity, tunnel width, height and cross section area. The network has been trained with experimental data obtained from experimental work. The hybrid neural network model learned the relationship for predicting the flame length in just 3000 training epochs. After successful learning, the model predicted the flame length.Keywords: tunnel fire, flame length, ANN, genetic algorithm
Procedia PDF Downloads 62214596 Spontaneous Transformation in U. Maritimus: A Case Series
Authors: Lur N. Dreier
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Spontaneous transformation in Ursus maritimus is generally considered to be seldom, albeit not, to this author's best knowledge, previously unpublished in the medical literature. However, no case series has to date described transformative spontaneous processes to filios hominum species. Norwegian public hospital system, is, however, especially the grounds of the specific climate in the Northern hemisphere, and because of a high suited to observe such transformations, both on income level. Hence, this paper describes, to our knowledge, the first case series of 25 patients undergoing treatment for spontaneous transformation in four Norwegian hospitals. The methodology was to include patients on a consecutive basis, identifying clinically and laboratory the typology in each of the four hospitals. The major findings were that the archetypes were heterogeneous, with coercive laboratory findings, with a high degree of redundancy of the process. This might potentially lead to many advances in the diagnostics.Keywords: case series, transformation, hominum species, maritimus species
Procedia PDF Downloads 24914595 Mutual Coupling Reduction between Patch Antenna Array Elements Using Metamaterial Z Shaped Resonators
Authors: Oossama Tabbabi, Mondher Labidi, Fethi Choubani, J. David
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Modern wireless communication systems require compact design, low cost and simple structure antennas to insure reliability, agility, and high efficiency characteristics. This paper presents a microstrip antenna array designed for 8 GHz applications. To reduce the mutual coupling effects, a Z shape metamaterial structure was imprinted in the microstrip antenna array composed of two elements. Simulation results show the improvement of mutual coupling by adding Z shape metamaterial structure to the antenna substrate. The proposed structure reduces mutual coupling by 19 dB. The simulation has been performed by using HFSS simulator.Keywords: antenna array, compact design, modern wireless communication, mutual coupling effects
Procedia PDF Downloads 33414594 An Ontology for Semantic Enrichment of RFID Systems
Authors: Haitham S. Hamza, Mohamed Maher, Shourok Alaa, Aya Khattab, Hadeal Ismail, Kamilia Hosny
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Radio Frequency Identification (RFID) has become a key technology in the margining concept of Internet of Things (IoT). Naturally, business applications would require the deployment of various RFID systems that are developed by different vendors and use various data formats. This heterogeneity poses a real challenge in developing large-scale IoT systems with RFID as integration is becoming very complex and challenging. Semantic integration is a key approach to deal with this challenge. To do so, ontology for RFID systems need to be developed in order to annotated semantically RFID systems, and hence, facilitate their integration. Accordingly, in this paper, we propose ontology for RFID systems. The proposed ontology can be used to semantically enrich RFID systems, and hence, improve their usage and reasoning. The usage of the proposed ontology is explained through a simple scenario in the health care domain.Keywords: RFID, semantic technology, ontology, sparql query language, heterogeneity
Procedia PDF Downloads 45514593 Mobile Health Programs by Government: A Content Analysis of Online Consumer Reviews
Authors: Ge Zhan
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Mobile health (mHealth) concerns the use of mobile technologies to deliver health care and improve wellness. In this paper, we ask the question of what are the drivers of positive consumer attitude toward mHealth programs. Answers to this question are important to consumer health, but existing marketing and health care service literature does not provide sufficient empirical conclusions on the use of mobile technologies for consumer health. This study aims to fill the knowledge gap by investigating mHealth use and consumer attitude. A content analysis was conducted with sample mHealth programs and online consumer reviews in Hong Kong, UK, US, and India. The research findings will contribute to marketing and health services literature.Keywords: mobile health, consumer attitude, content analysis, online marketing
Procedia PDF Downloads 37214592 Low Power CNFET SRAM Design
Authors: Pejman Hosseiniun, Rose Shayeghi, Iman Rahbari, Mohamad Reza Kalhor
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CNFET has emerged as an alternative material to silicon for high performance, high stability and low power SRAM design in recent years. SRAM functions as cache memory in computers and many portable devices. In this paper, a new SRAM cell design based on CNFET technology is proposed. The proposed SRAM cell design for CNFET is compared with SRAM cell designs implemented with the conventional CMOS and FinFET in terms of speed, power consumption, stability, and leakage current. The HSPICE simulation and analysis show that the dynamic power consumption of the proposed 8T CNFET SRAM cell’s is reduced about 48% and the SNM is widened up to 56% compared to the conventional CMOS SRAM structure at the expense of 2% leakage power and 3% write delay increase.Keywords: SRAM cell, CNFET, low power, HSPICE
Procedia PDF Downloads 39214591 A Development of a Weight-Balancing Control System Based On Android Operating System
Authors: Rattanathip Rattanachai, Piyachai Petchyen, Kunyanuth Kularbphettong
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This paper describes the development of a Weight- Balancing Control System based on the Android Operating System and it provides recommendations on ways of balancing of user’s weight based on daily metabolism process and need so that user can make informed decisions on his or her weight controls. The system also depicts more information on nutrition details. Furthermore, it was designed to suggest to users what kinds of foods they should eat and how to exercise in the right ways. We describe the design methods and functional components of this prototype. To evaluate the system performance, questionnaires for system usability and Black Box Testing were used to measure expert and user satisfaction. The results were satisfactory as followed: Means for experts and users were 3.94 and 4.07 respectively.Keywords: weight-balancing control, Android operating system, daily metabolism, black box testing
Procedia PDF Downloads 45714590 Clicking Based Graphical Password Scheme Resistant to Spyware
Authors: Bandar Alahmadi
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The fact that people tend to remember pictures better than texts, motivates researchers to develop graphical passwords as an alternative to textual passwords. Graphical passwords as such were introduced as a possible alternative to traditional text passwords, in which users prove their identity by clicking on pictures rather than typing alphanumerical text. In this paper, we present a scheme for graphical passwords that are resistant to shoulder surfing attacks and spyware attacks. The proposed scheme introduces a clicking technique to chosen images. First, the users choose a set of images, the images are then included in a grid where users can click in the cells around each image, the location of the click and the number of clicks are saved. As a result, the proposed scheme can be safe from shoulder surface and spyware attacks.Keywords: security, password, authentication, attack, applications
Procedia PDF Downloads 15214589 The Impact of the Global Financial Crises on MILA Stock Markets
Authors: Miriam Sosa, Edgar Ortiz, Alejandra Cabello
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This paper examines the volatility changes and leverage effects of the MILA stock markets and their changes since the 2007 global financial crisis. This group integrates the stock markets from Chile, Colombia, Mexico and Peru. Volatility changes and leverage effects are tested with a symmetric GARCH (1,1) and asymmetric TARCH (1,1) models with a dummy variable in the variance equation. Daily closing prices of the stock indexes of Chile (IPSA), Colombia (COLCAP), Mexico (IPC) and Peru (IGBVL) are examined for the period 2003:01 to 2015:02. The evidence confirms the presence of an overall increase in asymmetric market volatility in the Peruvian share market since the 2007 crisis.Keywords: financial crisis, Latin American Integrated Market, TARCH, GARCH
Procedia PDF Downloads 26014588 Design and Characterization of a CMOS Process Sensor Utilizing Vth Extractor Circuit
Authors: Rohana Musa, Yuzman Yusoff, Chia Chieu Yin, Hanif Che Lah
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This paper presents the design and characterization of a low power Complementary Metal Oxide Semiconductor (CMOS) process sensor. The design is targeted for implementation using Silterra’s 180 nm CMOS process technology. The proposed process sensor employs a voltage threshold (Vth) extractor architecture for detection of variations in the fabrication process. The process sensor generates output voltages in the range of 401 mV (fast-fast corner) to 443 mV (slow-slow corner) at nominal condition. The power dissipation for this process sensor is 6.3 µW with a supply voltage of 1.8V with a silicon area of 190 µm X 60 µm. The preliminary result of this process sensor that was fabricated indicates a close resemblance between test and simulated results.Keywords: CMOS process sensor, PVT sensor, threshold extractor circuit, Vth extractor circuit
Procedia PDF Downloads 16114587 Synthesis of Ethoxylated Amide as Bactericide to Enhance the Storage Period of Diesel Fuel Nanoemulsions
Authors: S. M. Abd-Altwab, M. R. Noor El-Din
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This paper aims to the synthesis of new ethoxylated amide as bactericides to prevent the growth of Gram +ve and –ve bacteria of water-in-diesel fuel nanoemulsions over a long period of time as three months. To realize it, eight kinetically stable water-in-diesel fuel nanoemulsions differing in surfactant concentrations and water contents ranging from 4 to 8 and 5 to 8 wt.,wt.,% of total weight of the nanoemulsions, respectively were formed at a temperature of 20 °C. The performance of this ethoxylated amide as bactericides agents against two strains of Gram-negative bacteria, namely, Pseudomonas aeruginosa and Escherichia coli, and two strains of Gram-positive bacteria namely, Staphylococcus aureus and Bacillus subtilis, were evaluated as antimicrobial agents. The maximum and minimum antimicrobial activities were 85 and 71 % against S. aureus and E. coli, respectively, at a concentration of 5 mg/l, pH 7, and 37 °C.Keywords: nanoemulsion, bacteriocide, diesel fuel, emulsifier
Procedia PDF Downloads 35014586 Preliminary Design Considerations for Achieving Stabilized Orbit, Telemetary, Command, and Ranging for HTS Communication Satellite
Authors: Ibrahim Isa Ali (Pantami), Abdu Jaafaru Bambale, Abimbola Alale, Danjuma Ibrahim Ndihgihdah, Muhammad Alkali, Adamu Idris Umar, Samson Olufunmilayo Abodunrin, Muhammad Dokko Zubairu, Moshood Kareem
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This paper discusses the consideration and trade-offs used for the implementation of robust systems for orbit stability; Telemetry, Command and Ranging (TC& R) for Nigcomsat-1R and applicability for planned NigComSat-2 satellites. NigComSat-1R satellite was built by China Academy of Space Technology (CAST). The Satellite designed with quad-band payload (L, C, Ku, and Ka) was launched on the 20th of December 2011. The functionality of all satellite is driven by robust systems including Attitude & Orbit Control System (AOCS) and TC&R. The planned Nigcomsat-2 is a high throughput Satellite expected to function with better AOCS and TC&R.Keywords: AOCS, CAST, Nigcomsat-1R, TC&R
Procedia PDF Downloads 9214585 Determination of the Gain in Learning the Free-Fall Motion of Bodies by Applying the Resource of Previous Concepts
Authors: Ricardo Merlo
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In this paper, we analyzed the different didactic proposals for teaching about the free fall motion of bodies available online. An important aspect was the interpretation of the direction and sense of the acceleration of gravity and of the falling velocity of a body, which is why we found different applications of the Cartesian reference system used and also different graphical presentations of the velocity as a function of time and of the distance traveled vertically by the body in the period of time that it was dropped from a height h0. In this framework, a survey of previous concepts was applied to a voluntary group of first-year university students of an Engineering degree before and after the development of the class of the subject in question. Then, Hake's index (0.52) was determined, which resulted in an average learning gain from the meaningful use of the reference system and the respective graphs of v=ƒ (t) and h=ƒ (t).Keywords: didactic gain, free–fall, physics teaching, previous knowledge
Procedia PDF Downloads 15114584 The Success of Local Community Participation in Ecotourism Site: A Case Study of Sukau
Authors: Awangku Hassanal Bahar Pengiran Bagul
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Ecotourism has been the signature tourism activity for Sabah since the 90s, and it has become a model of sustainable tourism development for Malaysia due to its ability to enhance conservation activities and local community development. This paper outlines the experience in developing indicators for the success of the local community participation of an ecotourism site, Sukau, in Sabah. The research was qualitative in nature and employed case study as its methodology. The outcome of this research suggested that Sukau has a mixed success with local community participation for the ecotourism activity. The community is in need of coaching and capacity building to intensify the ecotourism activity However, the ecotourism has successfully promoted conservation at its surrounding area.Keywords: community, ecotourism, rural development, success, sustainable tourism
Procedia PDF Downloads 37014583 A Text Classification Approach Based on Natural Language Processing and Machine Learning Techniques
Authors: Rim Messaoudi, Nogaye-Gueye Gning, François Azelart
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Automatic text classification applies mostly natural language processing (NLP) and other AI-guided techniques to automatically classify text in a faster and more accurate manner. This paper discusses the subject of using predictive maintenance to manage incident tickets inside the sociality. It focuses on proposing a tool that treats and analyses comments and notes written by administrators after resolving an incident ticket. The goal here is to increase the quality of these comments. Additionally, this tool is based on NLP and machine learning techniques to realize the textual analytics of the extracted data. This approach was tested using real data taken from the French National Railways (SNCF) company and was given a high-quality result.Keywords: machine learning, text classification, NLP techniques, semantic representation
Procedia PDF Downloads 8214582 Application of Finite Dynamic Programming to Decision Making in the Use of Industrial Residual Water Treatment Plants
Authors: Oscar Vega Camacho, Andrea Vargas Guevara, Ellery Rowina Ariza
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This paper presents the application of finite dynamic programming, specifically the "Markov Chain" model, as part of the decision making process of a company in the cosmetics sector located in the vicinity of Bogota DC. The objective of this process was to decide whether the company should completely reconstruct its wastewater treatment plant or instead optimize the plant through the addition of equipment. The goal of both of these options was to make the required improvements in order to comply with parameters established by national legislation regarding the treatment of waste before it is released into the environment. This technique will allow the company to select the best option and implement a solution for the processing of waste to minimize environmental damage and the acquisition and implementation costs.Keywords: decision making, Markov chain, optimization, wastewater
Procedia PDF Downloads 47314581 Quartz Crystal Microbalance Holder Design for On-Line Sensing in Liquid Applications
Authors: M. A. Amer, J. A. Chávez, M. J. García-Hernández, J. Salazar, A. Turó
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In this paper, the design of a QCM sensor for liquid media measurements in vertical position is described. A rugged and low-cost proof holder has been designed, the cost of which is significantly lower than those of traditional commercial holders. The crystal is not replaceable but it can be easily cleaned. Its small volume permits to be used by dipping it in the liquid with the desired location and orientation. The developed design has been experimentally validated by measuring changes in the resonance frequency and resistance of the QCM sensor immersed vertically in different calibrated aqueous glycerol solutions. The obtained results show a great agreement with the Kanazawa theoretical expression. Consequently, the designed QCM sensor would be appropriate for sensing applications in liquids, and might take part of a future on-line multichannel low-cost QCM-based measurement system.Keywords: holder design, liquid-media measurements, multi-channel measurements, QCM
Procedia PDF Downloads 36814580 Performance Assessment of GSO Satellites before and after Enhancing the Pointing Effect
Authors: Amr Emam, Joseph Victor, Mohamed Abd Elghany
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The paper presents the effect of the orbit inclination on the pointing error of the satellite antenna and consequently on its footprint on earth for a typical Ku- band payload system. The performance assessment is examined both theoretically and by means of practical measurements, taking also into account all additional sources of pointing errors, such as East-West station keeping, orbit eccentricity and actual attitude control performance. An implementation and computation of the sinusoidal biases in satellite roll and pitch used to compensate the pointing error of the satellite antenna coverage is studied and evaluated before and after the pointing corrections performed. A method for evaluation of the performance of the implemented biases has been introduced through measuring satellite received level from a tracking 11m and fixed 4.8m transmitting antenna before and after the implementation of the pointing corrections.Keywords: satellite, inclined orbit, pointing errors, coverage optimization
Procedia PDF Downloads 37714579 On Confidence Intervals for the Difference between Inverse of Normal Means with Known Coefficients of Variation
Authors: Arunee Wongkhao, Suparat Niwitpong, Sa-aat Niwitpong
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In this paper, we propose two new confidence intervals for the difference between the inverse of normal means with known coefficients of variation. One of these two confidence intervals for this problem is constructed based on the generalized confidence interval and the other confidence interval is constructed based on the closed form method of variance estimation. We examine the performance of these confidence intervals in terms of coverage probabilities and expected lengths via Monte Carlo simulation.Keywords: coverage probability, expected length, inverse of normal mean, coefficient of variation, generalized confidence interval, closed form method of variance estimation
Procedia PDF Downloads 29814578 The Study of Digital Transformation Skills and Competencies Framework at Umm Alqura University
Authors: Anod H. Alhazmi, Hanaa A. Yamani
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The lack of digital transformation professionals could prevent Saudi Arabia’s universities from providing digital services. The task of understanding what digital skills are needed within an organization, measuring the existing skills, and developing or attracting talents is a complex task. This paper provides a comprehensive analysis of the digital transformation skills needed in the organizations who seek digital transformation and identifies the skills and competencies framework DigSC built on Skills Framework for the Informational Age (SFIA) framework that is adopted by the Ministry of Communications and Information Technology (MCIT) in Saudi Arabia. The framework adopted identifies the main digital transformation skills clusters, categories and levels of responsibilities for each job description to fill the gap between this requirement and the digital skills supplied by the Umm Alqura University (UQU).Keywords: competencies, digital transformation, framework, skills, Umm Alqura university
Procedia PDF Downloads 17114577 Value Relevance of Accounting Information: Empirical Evidence from China
Authors: Ying Guo, Miaochan Li, David Yang, Xiao-Yan Li
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This paper examines the relevance of accounting information to stock prices at different periods using manufacturing companies listed in China’s Growth Enterprise Market (GEM). We find that both the average stock price at fiscal year-end and the average stock price one month after fiscal year-end are more relevant to the accounting information than the closing stock price four months after fiscal year-end. This implies that Chinese stock markets react before the public disclosure of accounting information, which may be due to information leak before official announcements. Our findings confirm that accounting information is relevant to stock prices for Chinese listed manufacturing companies, which is a critical question to answer for investors who have interest in Chinese companies.Keywords: accounting information, response time, value relevance, stock price
Procedia PDF Downloads 8014576 Improved K-Means Clustering Algorithm Using RHadoop with Combiner
Authors: Ji Eun Shin, Dong Hoon Lim
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Data clustering is a common technique used in data analysis and is used in many applications, such as artificial intelligence, pattern recognition, economics, ecology, psychiatry and marketing. K-means clustering is a well-known clustering algorithm aiming to cluster a set of data points to a predefined number of clusters. In this paper, we implement K-means algorithm based on MapReduce framework with RHadoop to make the clustering method applicable to large scale data. RHadoop is a collection of R packages that allow users to manage and analyze data with Hadoop. The main idea is to introduce a combiner as a function of our map output to decrease the amount of data needed to be processed by reducers. The experimental results demonstrated that K-means algorithm using RHadoop can scale well and efficiently process large data sets on commodity hardware. We also showed that our K-means algorithm using RHadoop with combiner was faster than regular algorithm without combiner as the size of data set increases.Keywords: big data, combiner, K-means clustering, RHadoop
Procedia PDF Downloads 41514575 An Overview of Nano-Particles Effect on Mechanical Properties of Composites
Authors: Ganiyu I. Lawal, Olatunde I. Sekunowo, Stephen I. Durowaye
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Composites depending on the nature of their constituents and mode of production are regarded as one of the advanced materials that drive today’s technology. This paper attempts a short review of the subject matter with a general aim of pushing to the next level the frontier of knowledge as it impacts the technology of nano-particles manufacturing. The objectives entail an effort to; aggregate recent research efforts in this field, analyse research findings and observations, streamline research efforts and support industry in taking decision on areas of fund deployment. It is envisaged that this work will serve as a quick hand-on compendium material for researchers in this field and a guide to relevant government departments wishing to fund a research whose outcomes have the potential of improving the nation’s GDP.Keywords: advanced materials, composites, mechanical properties, nano-particles
Procedia PDF Downloads 26214574 Numerical Investigation of Flow Boiling within Micro-Channels in the Slug-Plug Flow Regime
Authors: Anastasios Georgoulas, Manolia Andredaki, Marco Marengo
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The present paper investigates the hydrodynamics and heat transfer characteristics of slug-plug flows under saturated flow boiling conditions within circular micro-channels. Numerical simulations are carried out, using an enhanced version of the open-source CFD-based solver ‘interFoam’ of OpenFOAM CFD Toolbox. The proposed user-defined solver is based in the Volume Of Fluid (VOF) method for interface advection, and the mentioned enhancements include the implementation of a smoothing process for spurious current reduction, the coupling with heat transfer and phase change as well as the incorporation of conjugate heat transfer to account for transient solid conduction. In all of the considered cases in the present paper, a single phase simulation is initially conducted until a quasi-steady state is reached with respect to the hydrodynamic and thermal boundary layer development. Then, a predefined and constant frequency of successive vapour bubbles is patched upstream at a certain distance from the channel inlet. The proposed numerical simulation set-up can capture the main hydrodynamic and heat transfer characteristics of slug-plug flow regimes within circular micro-channels. In more detail, the present investigation is focused on exploring the interaction between subsequent vapour slugs with respect to their generation frequency, the hydrodynamic characteristics of the liquid film between the generated vapour slugs and the channel wall as well as of the liquid plug between two subsequent vapour slugs. The proposed investigation is carried out for the 3 different working fluids and three different values of applied heat flux in the heated part of the considered microchannel. The post-processing and analysis of the results indicate that the dynamics of the evolving bubbles in each case are influenced by both the upstream and downstream bubbles in the generated sequence. In each case a slip velocity between the vapour bubbles and the liquid slugs is evident. In most cases interfacial waves appear close to the bubble tail that significantly reduce the liquid film thickness. Finally, in accordance with previous investigations vortices that are identified in the liquid slugs between two subsequent vapour bubbles can significantly enhance the convection heat transfer between the liquid regions and the heated channel walls. The overall results of the present investigation can be used to enhance the present understanding by providing better insight of the complex, underpinned heat transfer mechanisms in saturated boiling within micro-channels in the slug-plug flow regime.Keywords: slug-plug flow regime, micro-channels, VOF method, OpenFOAM
Procedia PDF Downloads 25214573 Study on Network-Based Technology for Detecting Potentially Malicious Websites
Authors: Byung-Ik Kim, Hong-Koo Kang, Tae-Jin Lee, Hae-Ryong Park
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Cyber terrors against specific enterprises or countries have been increasing recently. Such attacks against specific targets are called advanced persistent threat (APT), and they are giving rise to serious social problems. The malicious behaviors of APT attacks mostly affect websites and penetrate enterprise networks to perform malevolent acts. Although many enterprises invest heavily in security to defend against such APT threats, they recognize the APT attacks only after the latter are already in action. This paper discusses the characteristics of APT attacks at each step as well as the strengths and weaknesses of existing malicious code detection technologies to check their suitability for detecting APT attacks. It then proposes a network-based malicious behavior detection algorithm to protect the enterprise or national networks.Keywords: Advanced Persistent Threat (APT), malware, network security, network packet, exploit kits
Procedia PDF Downloads 34614572 Analyzing Electricity Demand Multipliers in the Malaysian Economy
Authors: Hussain Ali Bekhet, Tuan Ab Rashid Bin Tuan Abdullah, Tahira Yasmin
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It is very important for electric utility to determine dominant sectors which have more impacts on electricity consumption in national economy system. The aim of this paper is to examine the electricity demand multipliers in Malaysia for (2005-2014) period. Malaysian Input-output tables, 2005 and 2010 are used. Besides, a new concept, electricity demand multiplier (EDM), is presented to identify key sectors imposing great impacts on electricity demand quantitatively. In order to testify the effectiveness of the Malaysian energy policies, it notes that there is fluctuation of the ranking sectors between 2005 and 2010. This could be reflected that there is efficiency with pace of development in Malaysia. This can be good indication for decision makers for designing future energy policies.Keywords: input-output model, demand multipliers, electricity, key sectors, Malaysia
Procedia PDF Downloads 358