Search results for: the traditional color scheme
2094 Fuzzy Optimization Multi-Objective Clustering Ensemble Model for Multi-Source Data Analysis
Authors: C. B. Le, V. N. Pham
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In modern data analysis, multi-source data appears more and more in real applications. Multi-source data clustering has emerged as a important issue in the data mining and machine learning community. Different data sources provide information about different data. Therefore, multi-source data linking is essential to improve clustering performance. However, in practice multi-source data is often heterogeneous, uncertain, and large. This issue is considered a major challenge from multi-source data. Ensemble is a versatile machine learning model in which learning techniques can work in parallel, with big data. Clustering ensemble has been shown to outperform any standard clustering algorithm in terms of accuracy and robustness. However, most of the traditional clustering ensemble approaches are based on single-objective function and single-source data. This paper proposes a new clustering ensemble method for multi-source data analysis. The fuzzy optimized multi-objective clustering ensemble method is called FOMOCE. Firstly, a clustering ensemble mathematical model based on the structure of multi-objective clustering function, multi-source data, and dark knowledge is introduced. Then, rules for extracting dark knowledge from the input data, clustering algorithms, and base clusterings are designed and applied. Finally, a clustering ensemble algorithm is proposed for multi-source data analysis. The experiments were performed on the standard sample data set. The experimental results demonstrate the superior performance of the FOMOCE method compared to the existing clustering ensemble methods and multi-source clustering methods.Keywords: clustering ensemble, multi-source, multi-objective, fuzzy clustering
Procedia PDF Downloads 1892093 Virtual Reality Applications for Building Indoor Engineering: Circulation Way-Finding
Authors: Atefeh Omidkhah Kharashtomi, Rasoul Hedayat Nejad, Saeed Bakhtiyari
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Circulation paths and indoor connection network of the building play an important role both in the daily operation of the building and during evacuation in emergency situations. The degree of legibility of the paths for navigation inside the building has a deep connection with the perceptive and cognitive system of human, and the way the surrounding environment is being perceived. Human perception of the space is based on the sensory systems in a three-dimensional environment, and non-linearly, so it is necessary to avoid reducing its representations in architectural design as a two-dimensional and linear issue. Today, the advances in the field of virtual reality (VR) technology have led to various applications, and architecture and building science can benefit greatly from these capabilities. Especially in cases where the design solution requires a detailed and complete understanding of the human perception of the environment and the behavioral response, special attention to VR technologies could be a priority. Way-finding in the indoor circulation network is a proper example for such application. Success in way-finding could be achieved if human perception of the route and the behavioral reaction have been considered in advance and reflected in the architectural design. This paper discusses the VR technology applications for the way-finding improvements in indoor engineering of the building. In a systematic review, with a database consisting of numerous studies, firstly, four categories for VR applications for circulation way-finding have been identified: 1) data collection of key parameters, 2) comparison of the effect of each parameter in virtual environment versus real world (in order to improve the design), 3) comparing experiment results in the application of different VR devices/ methods with each other or with the results of building simulation, and 4) training and planning. Since the costs of technical equipment and knowledge required to use VR tools lead to the limitation of its use for all design projects, priority buildings for the use of VR during design are introduced based on case-studies analysis. The results indicate that VR technology provides opportunities for designers to solve complex buildings design challenges in an effective and efficient manner. Then environmental parameters and the architecture of the circulation routes (indicators such as route configuration, topology, signs, structural and non-structural components, etc.) and the characteristics of each (metrics such as dimensions, proportions, color, transparency, texture, etc.) are classified for the VR way-finding experiments. Then, according to human behavior and reaction in the movement-related issues, the necessity of scenario-based and experiment design for using VR technology to improve the design and receive feedback from the test participants has been described. The parameters related to the scenario design are presented in a flowchart in the form of test design, data determination and interpretation, recording results, analysis, errors, validation and reporting. Also, the experiment environment design is discussed for equipment selection according to the scenario, parameters under study as well as creating the sense of illusion in the terms of place illusion, plausibility and illusion of body ownership.Keywords: virtual reality (VR), way-finding, indoor, circulation, design
Procedia PDF Downloads 742092 Recognition of a Thinly Bedded Distal Turbidite: A Case Study from a Proterozoic Delta System, Chaossa Formation, Simla Group, Western Lesser Himalaya, India
Authors: Priyanka Mazumdar, Ananya Mukhopadhyay
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A lot of progress has been achieved in the research of turbidites during the last decades. However, their relationship to delta systems still deserves further attention. This paper addresses example of fine grained turbidite from a pro-deltaic deposit of a Proterozoic mixed energy delta system exposed along Chaossa-Baliana river section of the Chaossa Formation of the Simla Basin. Lithostratigraphic analysis of the Chaossa Formation reveals three major facies associations (prodelta deposit-FA1, delta slope deposit-FA2 and delta front deposit-FA3) based on lithofacies types, petrography and sedimentary structures. Detailed process-based facies and paleoenvironmental analysis of the study area have led to identification of more than150 m thick coarsening-upwards deltaic successions composed of fine grained turbidites overlain by delta slope deposits. Erosional features are locally common at the base of turbidite beds and still more widespread at the top. The complete sequence has eight sub-divisions that are here termed T1 to T8. The basal subdivision (T1) comprises a massive graded unit with a sharp, scoured base, internal parallel-lamination and cross-lamination. The overlying sequence shows textural and compositional grading through alternating silt and mud laminae (T2). T2 is overlying by T3 which is characterized by climbing ripple and cross lamination. Parallel laminae are the predominant facies attributes of T4 which caps the T3 unit. T5 has a loaded scour base and is mainly characterized laminated silt. The topmost three divisions, graded mud (T6), ungraded mud (T7) and laminated mud (T8). The proposed sequence is analogous to the Bouma (1962) structural scheme for sandy turbidites. Repetition of partial sequences represents deposition from different stages of evolution of a large, muddy, turbidity flow. Detailed facies analysis of the study area reveals that the sediments of the turbidites developed during normal regression at the stage of stable or marginally rising sea level. Thin-bedded turbidites were deposited predominantly by turbidity currents in the relatively shallower part of the Simla basin. The fine-grained turbidites are developed by resedimentation of delta-front sands and slumping of upper pro-delta muds.Keywords: turbidites, prodelta, proterozoic, Simla Basin, Bouma sequence
Procedia PDF Downloads 2692091 Using Thinking Blocks to Encourage the Use of Higher Order Thinking Skills among Students When Solving Problems on Fractions
Authors: Abdul Halim Abdullah, Nur Liyana Zainal Abidin, Mahani Mokhtar
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Problem-solving is an activity which can encourage students to use Higher Order Thinking Skills (HOTS). Learning fractions can be challenging for students since empirical evidence shows that students experience difficulties in solving the fraction problems. However, visual methods can help students to overcome the difficulties since the methods help students to make meaningful visual representations and link abstract concepts in Mathematics. Therefore, the purpose of this study was to investigate whether there were any changes in students’ HOTS at the four highest levels when learning the fractions by using Thinking Blocks. 54 students participated in a quasi-experiment using pre-tests and post-tests. Students were divided into two groups. The experimental group (n=32) received a treatment to improve the students’ HOTS and the other group acted as the control group (n=22) which used a traditional method. Data were analysed by using Mann-Whitney test. The results indicated that during post-test, students who used Thinking Blocks showed significant improvement in their HOTS level (p=0.000). In addition, the results of post-test also showed that the students’ performance improved significantly at the four highest levels of HOTS; namely, application (p=0.001), analyse (p=0.000), evaluate (p=0.000), and create (p=0.000). Therefore, it can be concluded that Thinking Blocks can effectively encourage students to use the four highest levels of HOTS which consequently enable them to solve fractions problems successfully.Keywords: Thinking Blocks, Higher Order Thinking Skills (HOTS), fractions, problem solving
Procedia PDF Downloads 2702090 Anomaly Detection in Financial Markets Using Tucker Decomposition
Authors: Salma Krafessi
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The financial markets have a multifaceted, intricate environment, and enormous volumes of data are produced every day. To find investment possibilities, possible fraudulent activity, and market oddities, accurate anomaly identification in this data is essential. Conventional methods for detecting anomalies frequently fail to capture the complex organization of financial data. In order to improve the identification of abnormalities in financial time series data, this study presents Tucker Decomposition as a reliable multi-way analysis approach. We start by gathering closing prices for the S&P 500 index across a number of decades. The information is converted to a three-dimensional tensor format, which contains internal characteristics and temporal sequences in a sliding window structure. The tensor is then broken down using Tucker Decomposition into a core tensor and matching factor matrices, allowing latent patterns and relationships in the data to be captured. A possible sign of abnormalities is the reconstruction error from Tucker's Decomposition. We are able to identify large deviations that indicate unusual behavior by setting a statistical threshold. A thorough examination that contrasts the Tucker-based method with traditional anomaly detection approaches validates our methodology. The outcomes demonstrate the superiority of Tucker's Decomposition in identifying intricate and subtle abnormalities that are otherwise missed. This work opens the door for more research into multi-way data analysis approaches across a range of disciplines and emphasizes the value of tensor-based methods in financial analysis.Keywords: tucker decomposition, financial markets, financial engineering, artificial intelligence, decomposition models
Procedia PDF Downloads 692089 Effects of Abiotic Stress on the Phytochemical Content and Bioactivity of Pistacia lentiscus L.
Authors: S. Mamoucha, N. Tsafantakis, Α. Ioannidis, S. Chatzipanagiotou, C. Nikolaou, L. Skaltsounis, N. Fokialakis, N. Christodoulakis
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Introduction: Plant secondary metabolites (SM) can be grouped into three chemically distinct groups: terpenes, phenolics, and nitrogen-containing compounds. For many years the adaptive significance of SM was unknown. They were thought to be functionless end-products. Currently it is accepted that many secondary metabolites (also known as natural products) have important ecological roles in plants. For instance, they serve as attractants (odor, color, taste) for pollinators and seed-dispersing animals. Moreover, they protect plants from herbivores, microbial pathogens and from environmental stress (high and low temperatures, drought, alkalinity, salinity, radiation etc). It is well known that both biotic and abiotic stress often increase the accumulation of SM. The local climatic conditions, seasonal changes, external factors such as light, temperature, humidity affect the biosynthesis and composition of secondary metabolites. A well known dioecious evergreen plant, Pistacia lentiscus L. (mastic tree), was selected in order to study the metabolic variations occur in response to the different climate conditions, due to the seasonal variation and its effect on the biosynthesis of bioactive compounds. Materials-methods: Young and mature leaves were collected in January and July 2014, dried and extracted by accelerated solvent extraction (Dionex ASE™ 350) using solvents of increased polarity (DCM, MeOH, and H2O). GC-MS and UHPLC-HRMS analysis were carried out in order to define the nature and the relative abundance of SM. The antibacterial activity was evaluated by using the Agar Disc Diffusion Assay against ATCC and clinical isolates strains: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Streptococcus mutans and Klebsiella pneumoniae. All tests were carried out in duplicate and the average radii of the inhibition zones were calculated for each extract. Results: According to the phytochemical profile obtained from each extract, the biosynthesis of SM varied both qualitatively and quantitatively under the two different types of seasonal stress. With exception of the biologically inactive nonpolar DCM extract of July, all extracts inhibited the growth of most of the investigated microorganisms. A clear positive correlation has been observed between the relative abundance of SM and the bioactivity of the DCM extracts of January and July. Observed changes during phytochemical analysis were mainly focused on the triterpenoid content. On the other hand, the bioactivity of the polar extracts (MeOH and H2O) of January and July resulted practically invariable against most of the microorganisms, besides the significant variation of the SM content due to the seasonal variation. Conclusion: Our results clearly confirmed the hypothesis of abiotic stress as an important regulating factor that significantly affects the biosynthesis of secondary metabolites and thus the presence of bioactive compounds. Acknowledgment: This work was supported by IKY - State Scholarship Foundation, Athens, Greece.Keywords: antibacterial screening, phytochemical profile, Pistacia lentiscus, abiotic stress
Procedia PDF Downloads 2562088 Television and Virtual Public Sphere: A Study on Malayali Tribes in Salem District, Tamil Nadu
Authors: P. Viduthalai, A. K. Divakar, V. Natarajan
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Media is one of the powerful tools that manipulate the world in numerous aspects especially in the form of a communication process. For instance, the concept of the public sphere, which was earlier represented by landlords and elites has now transformed into a virtual public sphere, which is also represented by marginalized people. Unfortunately, this acquisition is still paradoxical. Though the media proliferation and its effects are humongous, still it has not been the same throughout the world. Inequality in access to media has created a technological divide among people. Finally, globalization and approach by the government towards using media for development communication has significantly changed the way in which the media reaches every nook and corner. Monarchy, oligarchy, republic and democracy together form the basis of most governments of the world. Of which, democracy is the one with the highest involvement and participation of the people. Ideally, the participation of the people is what, that keeps the democracy running. A healthy democracy is possible only when people are able to access information that makes citizens responsible and serves to check the functioning of their elected representatives. On one side the media consumption of people plays a crucial role in the formation of the public sphere, and on the other side, big media conglomerates are a serious threat to community participation, which is a goal that the media should strive for in a country like India. How different people consume these different media, differs greatly from length and breadth of the country. Another aspect of this media consumption is that it isn’t passive. People usage and consumption of media are related with the gratification that they derive from the particular media. This aspect varies from person to person and from society to society according to both internal and external factors. This article sets out from the most underlying belief that Malayali Tribes have adopted television and becomes a part of daily life and a day never passes without it especially after the introduction of Free Television Scheme by the past state government. Though they are living in hilly and socially isolated places, they too have started accessing media for understanding about the people of the plains and their culture, dictated by their interest. Many of these interests appear to have a social and psychological origin. The present research attempts to study how gratification of these needs lead Malayali Tribes to form such a virtual public sphere where they could communicate with people of the plains. Data was collected through survey method, from 300 respondents on “Exposure towards Television and their perception”. Conventional anthropological methods like unstructured interviews were also used to supplement the data collection efforts in the three taluks namely Yercaud, Pethanayankkanpalayam and Panamaraththuppatty in Salem district of TamilNadu. The results highlight the role of Television in gratifying needs of the Malayali Tribes.Keywords: democracy, gratification, Malayali Tribes and television, virtual public sphere
Procedia PDF Downloads 2542087 Fault Tolerant (n,k)-star Power Network Topology for Multi-Agent Communication in Automated Power Distribution Systems
Authors: Ning Gong, Michael Korostelev, Qiangguo Ren, Li Bai, Saroj K. Biswas, Frank Ferrese
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This paper investigates the joint effect of the interconnected (n,k)-star network topology and Multi-Agent automated control on restoration and reconfiguration of power systems. With the increasing trend in development in Multi-Agent control technologies applied to power system reconfiguration in presence of faulty components or nodes. Fault tolerance is becoming an important challenge in the design processes of the distributed power system topology. Since the reconfiguration of a power system is performed by agent communication, the (n,k)-star interconnected network topology is studied and modeled in this paper to optimize the process of power reconfiguration. In this paper, we discuss the recently proposed (n,k)-star topology and examine its properties and advantages as compared to the traditional multi-bus power topologies. We design and simulate the topology model for distributed power system test cases. A related lemma based on the fault tolerance and conditional diagnosability properties is presented and proved both theoretically and practically. The conclusion is reached that (n,k)-star topology model has measurable advantages compared to standard bus power systems while exhibiting fault tolerance properties in power restoration, as well as showing efficiency when applied to power system route discovery.Keywords: (n, k)-star topology, fault tolerance, conditional diagnosability, multi-agent system, automated power system
Procedia PDF Downloads 5122086 Fault Tolerant (n, k)-Star Power Network Topology for Multi-Agent Communication in Automated Power Distribution Systems
Authors: Ning Gong, Michael Korostelev, Qiangguo Ren, Li Bai, Saroj Biswas, Frank Ferrese
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This paper investigates the joint effect of the interconnected (n,k)-star network topology and Multi-Agent automated control on restoration and reconfiguration of power systems. With the increasing trend in development in Multi-Agent control technologies applied to power system reconfiguration in presence of faulty components or nodes. Fault tolerance is becoming an important challenge in the design processes of the distributed power system topology. Since the reconfiguration of a power system is performed by agent communication, the (n,k)-star interconnected network topology is studied and modeled in this paper to optimize the process of power reconfiguration. In this paper, we discuss the recently proposed (n,k)-star topology and examine its properties and advantages as compared to the traditional multi-bus power topologies. We design and simulate the topology model for distributed power system test cases. A related lemma based on the fault tolerance and conditional diagnosability properties is presented and proved both theoretically and practically. The conclusion is reached that (n,k)-star topology model has measurable advantages compared to standard bus power systems while exhibiting fault tolerance properties in power restoration, as well as showing efficiency when applied to power system route discovery.Keywords: (n, k)-star topology, fault tolerance, conditional diagnosability, multi-agent system, automated power system
Procedia PDF Downloads 4652085 The Cell Viability Study of Extracts of Bark, Flowers, Leaves and Seeds of Indian Dhak Tree, Flame of Forest
Authors: Madhavi S. Apte, Milind Bhitre
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In pharmaceutical research and new drug development, medicinal plants have important roles. Similarly, Indian dhak tree belonging to family Fabaceae has been widely used in the traditional Indian medical system of ‘Ayurveda’ for the treatment of a variety of ailments. Hence the cell viability study was undertaken to evaluate and compare the activity of extracts of various parts like flower, bark, leaf, seed by conducting MTT assay method along with other pharmacognostical studies. The methanolic extracts of bark, flowers, leaves, and seeds were used for the study. The cell viability MTT assay was performed using the standard operating procedures. The extracts were dissolved in DMSO and serially diluted with complete medium to get the concentrations range of test concentration. DMSO concentration was kept < 0.1% in all the samples. HUVEC cells maintained in appropriate conditions were seeded in 96 well plates and treated with different concentrations of the test samples and incubated at 37°C, 5% CO₂ for 96 hours. MTT reagent was added to the wells and incubated for 4 hours; the dark blue formazan product formed by the cells was dissolved in DMSO under a safety cabinet and read at 550nm. Percentage inhibitions were calculated and plotted with the concentrations used to calculate the IC50 values. The bark, flower, leaves and seed extracts have shown the cytotoxicity activity and can be further studied for antiangiogenesis activity.Keywords: pharmacognosy, Cell viability, MTT assay, anti-angiogenesis
Procedia PDF Downloads 2952084 Technology Valuation of Unconventional Gas R&D Project Using Real Option Approach
Authors: Young Yoon, Jinsoo Kim
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The adoption of information and communication technologies (ICT) in all industry is growing under industry 4.0. Many oil companies also are increasingly adopting ICT to improve the efficiency of existing operations, take more accurate and quicker decision making and reduce entire cost by optimization. It is true that ICT is playing an important role in the process of unconventional oil and gas development and companies must take advantage of ICT to gain competitive advantage. In this study, real option approach has been applied to Unconventional gas R&D project to evaluate ICT of them. Many unconventional gas reserves such as shale gas and coal-bed methane(CBM) has developed due to technological improvement and high energy price. There are many uncertainties in unconventional development on the three stage(Exploration, Development, Production). The traditional quantitative benefits-cost method, such as net present value(NPV) is not sufficient for capturing ICT value. We attempted to evaluate the ICT valuation by applying the compound option model; the model is applied to real CBM project case, showing how it consider uncertainties. Variables are treated as uncertain and a Monte Carlo simulation is performed to consider variables effect. Acknowledgement—This work was supported by the Energy Efficiency & Resources Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20152510101880) and by the National Research Foundation of Korea Grant funded by the Korean Government (NRF-205S1A3A2046684).Keywords: information and communication technologies, R&D, real option, unconventional gas
Procedia PDF Downloads 2292083 Origins of Strict Liability for Abnormally Dangerous Activities in the United States, Rylands v. Fletcher and a General Clause of Strict Liability in the UK
Authors: Maria Lubomira Kubica
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The paper reveals the birth and evolution of the British precedent Rylands v. Fletcher that, once adopted on the other side of the Ocean (in United States), gave rise to a general clause of liability for abnormally dangerous activities recognized by the §20 of the American Restatements of the Law Third, Liability for Physical and Emotional Harm. The main goal of the paper was to analyze the development of the legal doctrine and of the case law posterior to the precedent together with the intent of the British judicature to leapfrog from the traditional rule contained in Rylands v. Fletcher to a general clause similar to that introduced in the United States and recently also on the European level. As it is well known, within the scope of tort law two different initiatives compete with the aim of harmonizing the European laws: European Group on Tort Law with its Principles of European Tort Law (hereinafter PETL) in which article 5:101 sets forth a general clause for strict liability for abnormally dangerous activities and Study Group on European Civil Code with its Common Frame of Reference (CFR) which promotes rather ad hoc model of listing out determined cases of strict liability. Very narrow application scope of the art. 5:101 PETL, restricted only to abnormally dangerous activities, stays in opposition to very broad spectrum of strict liability cases governed by the CFR. The former is a perfect example of a general clause that offers a minimum and basic standard, possibly acceptable also in those countries in which, like in the United Kingdom, this regime of liability is completely marginalized.Keywords: Rylands v. Fletcher, strict liability, dangerous activities, general clause
Procedia PDF Downloads 3212082 A Methodology for Automatic Diversification of Document Categories
Authors: Dasom Kim, Chen Liu, Myungsu Lim, Su-Hyeon Jeon, ByeoungKug Jeon, Kee-Young Kwahk, Namgyu Kim
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Recently, numerous documents including unstructured data and text have been created due to the rapid increase in the usage of social media and the Internet. Each document is usually provided with a specific category for the convenience of the users. In the past, the categorization was performed manually. However, in the case of manual categorization, not only can the accuracy of the categorization be not guaranteed but the categorization also requires a large amount of time and huge costs. Many studies have been conducted towards the automatic creation of categories to solve the limitations of manual categorization. Unfortunately, most of these methods cannot be applied to categorizing complex documents with multiple topics because the methods work by assuming that one document can be categorized into one category only. In order to overcome this limitation, some studies have attempted to categorize each document into multiple categories. However, they are also limited in that their learning process involves training using a multi-categorized document set. These methods therefore cannot be applied to multi-categorization of most documents unless multi-categorized training sets are provided. To overcome the limitation of the requirement of a multi-categorized training set by traditional multi-categorization algorithms, we previously proposed a new methodology that can extend a category of a single-categorized document to multiple categorizes by analyzing relationships among categories, topics, and documents. In this paper, we design a survey-based verification scenario for estimating the accuracy of our automatic categorization methodology.Keywords: big data analysis, document classification, multi-category, text mining, topic analysis
Procedia PDF Downloads 2722081 Folding of β-Structures via the Polarized Structure-Specific Backbone Charge (PSBC) Model
Authors: Yew Mun Yip, Dawei Zhang
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Proteins are the biological machinery that executes specific vital functions in every cell of the human body by folding into their 3D structures. When a protein misfolds from its native structure, the machinery will malfunction and lead to misfolding diseases. Although in vitro experiments are able to conclude that the mutations of the amino acid sequence lead to incorrectly folded protein structures, these experiments are unable to decipher the folding process. Therefore, molecular dynamic (MD) simulations are employed to simulate the folding process so that our improved understanding of the folding process will enable us to contemplate better treatments for misfolding diseases. MD simulations make use of force fields to simulate the folding process of peptides. Secondary structures are formed via the hydrogen bonds formed between the backbone atoms (C, O, N, H). It is important that the hydrogen bond energy computed during the MD simulation is accurate in order to direct the folding process to the native structure. Since the atoms involved in a hydrogen bond possess very dissimilar electronegativities, the more electronegative atom will attract greater electron density from the less electronegative atom towards itself. This is known as the polarization effect. Since the polarization effect changes the electron density of the two atoms in close proximity, the atomic charges of the two atoms should also vary based on the strength of the polarization effect. However, the fixed atomic charge scheme in force fields does not account for the polarization effect. In this study, we introduce the polarized structure-specific backbone charge (PSBC) model. The PSBC model accounts for the polarization effect in MD simulation by updating the atomic charges of the backbone hydrogen bond atoms according to equations derived between the amount of charge transferred to the atom and the length of the hydrogen bond, which are calculated from quantum-mechanical calculations. Compared to other polarizable models, the PSBC model does not require quantum-mechanical calculations of the peptide simulated at every time-step of the simulation and maintains the dynamic update of atomic charges, thereby reducing the computational cost and time while accounting for the polarization effect dynamically at the same time. The PSBC model is applied to two different β-peptides, namely the Beta3s/GS peptide, a de novo designed three-stranded β-sheet whose structure is folded in vitro and studied by NMR, and the trpzip peptides, a double-stranded β-sheet where a correlation is found between the type of amino acids that constitute the β-turn and the β-propensity.Keywords: hydrogen bond, polarization effect, protein folding, PSBC
Procedia PDF Downloads 2702080 Analysis and Experimental Research on the Influence of Lubricating Oil on the Transmission Efficiency of New Energy Vehicle Gearbox
Authors: Chen Yong, Bi Wangyang, Zang Libin, Li Jinkai, Cheng Xiaowei, Liu Jinmin, Yu Miao
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New energy vehicle power transmission systems continue to develop in the direction of high torque, high speed, and high efficiency. The cooling and lubrication of the motor and the transmission system are integrated, and new requirements are placed on the lubricants for the transmission system. The effects of traditional lubricants and special lubricants for new energy vehicles on transmission efficiency were studied through experiments and simulation methods. A mathematical model of the transmission efficiency of the lubricating oil in the gearbox was established. The power loss of each part was analyzed according to the working conditions. The relationship between the speed and the characteristics of different lubricating oil products on the power loss of the stirring oil was discussed. The minimum oil film thickness was required for the life of the gearbox. The accuracy of the calculation results was verified by the transmission efficiency test conducted on the two-motor integrated test bench. The results show that the efficiency increases first and then decreases with the increase of the speed and decreases with the increase of the kinematic viscosity of the lubricant. The increase of the kinematic viscosity amplifies the transmission power loss caused by the high speed. New energy vehicle special lubricants have less attenuation of transmission efficiency in the range above mid-speed. The research results provide a theoretical basis and guidance for the evaluation and selection of transmission efficiency of gearbox lubricants for new energy vehicles.Keywords: new energy vehicles, lubricants, transmission efficiency, kinematic viscosity, test and simulation
Procedia PDF Downloads 1312079 Characterisation of Wind-Driven Ventilation in Complex Terrain Conditions
Authors: Daniel Micallef, Damien Bounaudet, Robert N. Farrugia, Simon P. Borg, Vincent Buhagiar, Tonio Sant
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The physical effects of upstream flow obstructions such as vegetation on cross-ventilation phenomena of a building are important for issues such as indoor thermal comfort. Modelling such effects in Computational Fluid Dynamics simulations may also be challenging. The aim of this work is to establish the cross-ventilation jet behaviour in such complex terrain conditions as well as to provide guidelines on the implementation of CFD numerical simulations in order to model complex terrain features such as vegetation in an efficient manner. The methodology consists of onsite measurements on a test cell coupled with numerical simulations. It was found that the cross-ventilation flow is highly turbulent despite the very low velocities encountered internally within the test cells. While no direct measurement of the jet direction was made, the measurements indicate that flow tends to be reversed from the leeward to the windward side. Modelling such a phenomenon proves challenging and is strongly influenced by how vegetation is modelled. A solid vegetation tends to predict better the direction and magnitude of the flow than a porous vegetation approach. A simplified terrain model was also shown to provide good comparisons with observation. The findings have important implications on the study of cross-ventilation in complex terrain conditions since the flow direction does not remain trivial, as with the traditional isolated building case.Keywords: complex terrain, cross-ventilation, wind driven ventilation, wind resource, computational fluid dynamics, CFD
Procedia PDF Downloads 3952078 The Changing Role of the Chief Academic Officer in American Higher Education: Causes and Consequences
Authors: Michael W. Markowitz, Jeffrey Gingerich
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The landscape of higher education in the United States has undergone significant changes in the last 25 years. What was once a domain of competition among prospective students for a limited number of college and university seats has become a marketplace in which institutions vie for the enrollment of educational consumers. A central figure in this paradigm shift has been the Chief Academic Officer (CAO), whose institutional role has also evolved beyond academics to include such disparate responsibilities as strategic planning, fiscal oversight, student recruitment, fundraising and personnel management. This paper explores the scope and impact of this transition by, first, explaining its context: the intersection of key social, economic and political factors in neo-conservative, late 20th Century America that redefined the value and accountability of institutions of higher learning. This context, in turn, is shown to have redefined the role and function of the CAO from a traditional academic leader to one centered on the successful application of corporate principles of organizational and fiscal management. Information gathered from a number of sitting Provosts, Vice-Presidents of Academic Affairs and Deans of Faculty is presented to illustrate the parameters of this change, as well as the extent to which today’s academic officers feel prepared and equipped to fulfill this broader institutional role. The paper concludes with a discussion of the impact of this transition on the American academy and whether it serves as a portend of change to come in higher education systems around the globe.Keywords: academic administration, higher education, leadership, organizational management
Procedia PDF Downloads 2202077 3D Multiuser Virtual Environments in Language Teaching
Authors: Hana Maresova, Daniel Ecler
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The paper focuses on the use of 3D multi-user virtual environments (MUVE) in language teaching and presents the results of four years of research at the Faculty of Education, Palacký University in Olomouc (Czech Republic). In the form of an experiment, mother tongue language teaching in the 3D virtual worlds Second Life and Kitely (experimental group) and parallel traditional teaching on identical topics representing teacher's interpretation using a textbook (control group) were implemented. The didactic test, which was presented to the experimental and control groups in an identical form before and after the instruction, verified the effect of the instruction in the experimental group by comparing the results obtained by both groups. Within the three components of mother-tongue teaching (vocabulary, literature, style and communication education), the students in the literature group achieved partially better results (statistically significant in the case of items devoted to the area of visualization of the learning topic), while in the case of grammar and style education the respondents of the control group achieved better results. On the basis of the results obtained, we can conclude that the most appropriate use of MUVE can be seen in the teaching of those topics that provide the possibility of dramatization, experiential learning and group involvement and cooperation, on the contrary, with regard to the need to divide students attention between the topic taught and the control of avatar and movement in virtual reality as less suitable for teaching in the area of memorization of the topic or concepts.Keywords: distance learning, 3D virtual environments, online teaching, language teaching
Procedia PDF Downloads 1632076 Integrated Evaluation of Green Design and Green Manufacturing Processes Using a Mathematical Model
Authors: Yuan-Jye Tseng, Shin-Han Lin
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In this research, a mathematical model for integrated evaluation of green design and green manufacturing processes is presented. To design a product, there can be alternative options to design the detailed components to fulfill the same product requirement. In the design alternative cases, the components of the product can be designed with different materials and detailed specifications. If several design alternative cases are proposed, the different materials and specifications can affect the manufacturing processes. In this paper, a new concept for integrating green design and green manufacturing processes is presented. A green design can be determined based the manufacturing processes of the designed product by evaluating the green criteria including energy usage and environmental impact, in addition to the traditional criteria of manufacturing cost. With this concept, a mathematical model is developed to find the green design and the associated green manufacturing processes. In the mathematical model, the cost items include material cost, manufacturing cost, and green related cost. The green related cost items include energy cost and environmental cost. The objective is to find the decisions of green design and green manufacturing processes to achieve the minimized total cost. In practical applications, the decision-making can be made to select a good green design case and its green manufacturing processes. In this presentation, an example product is illustrated. It shows that the model is practical and useful for integrated evaluation of green design and green manufacturing processes.Keywords: supply chain management, green supply chain, green design, green manufacturing, mathematical model
Procedia PDF Downloads 8072075 Large Scale Production of Polyhydroxyalkanoates (PHAs) from Waste Water: A Study of Techno-Economics, Energy Use, and Greenhouse Gas Emissions
Authors: Cora Fernandez Dacosta, John A. Posada, Andrea Ramirez
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The biodegradable family of polymers polyhydroxyalkanoates are interesting substitutes for convectional fossil-based plastics. However, the manufacturing and environmental impacts associated with their production via intracellular bacterial fermentation are strongly dependent on the raw material used and on energy consumption during the extraction process, limiting their potential for commercialization. Industrial wastewater is studied in this paper as a promising alternative feedstock for waste valorization. Based on results from laboratory and pilot-scale experiments, a conceptual process design, techno-economic analysis and life cycle assessment are developed for the large-scale production of the most common type of polyhydroxyalkanoate, polyhydroxbutyrate. Intracellular polyhydroxybutyrate is obtained via fermentation of microbial community present in industrial wastewater and the downstream processing is based on chemical digestion with surfactant and hypochlorite. The economic potential and environmental performance results help identifying bottlenecks and best opportunities to scale-up the process prior to industrial implementation. The outcome of this research indicates that the fermentation of wastewater towards PHB presents advantages compared to traditional PHAs production from sugars because the null environmental burdens and financial costs of the raw material in the bioplastic production process. Nevertheless, process optimization is still required to compete with the petrochemicals counterparts.Keywords: circular economy, life cycle assessment, polyhydroxyalkanoates, waste valorization
Procedia PDF Downloads 4572074 The Real Ambassador: How Hip Hop Culture Connects and Educates across Borders
Authors: Frederick Gooding
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This paper explores how many Hip Hop artists have intentionally and strategically invoked sustainability principles of people, planet and profits as a means to create community, compensate for and cope with structural inequalities in society. These themes not only create community within one's country, but the powerful display and demonstration of these narratives create community on a global plane. Listeners of Hip Hop are therefore able to learn about the political events occurring in another country free of censure, and establish solidarity worldwide. Hip Hop therefore can be an ingenious tool to create self-worth, recycle positive imagery, and serve as a defense mechanism from institutional and structural forces that conspire to make an upward economic and social trajectory difficult, if not impossible for many people of color, all across the world. Although the birthplace of Hip Hop, the United States of America, is still predominately White, it has undoubtedly grown more diverse at a breath-taking pace in recent decades. Yet, whether American mainstream media will fully reflect America’s newfound diversity remains to be seen. As it stands, American mainstream media is seen and enjoyed by diverse audiences not just in America, but all over the world. Thus, it is imperative that further inquiry is conducted about one of the fastest growing genres within one of the world’s largest and most influential media industries generating upwards of $10 billion annually. More importantly, hip hop, its music and associated culture collectively represent a shared social experience of significant value. They are important tools used both to inform and influence economic, social and political identity. Conversely, principles of American exceptionalism often prioritize American political issues over those of others, thereby rendering a myopic political view within the mainstream. This paper will therefore engage in an international contextualization of the global phenomena entitled Hip Hop by exploring the creative genius and marketing appeal of Hip Hop within the global context of information technology, political expression and social change in addition to taking a critical look at historically racialized imagery within mainstream media. Many artists the world over have been able to freely express themselves and connect with broader communities outside of their own borders, all through the sound practice of the craft of Hip Hop. An empirical understanding of political, social and economic forces within the United States will serve as a bridge for identifying and analyzing transnational themes of commonality for typically marginalized or disaffected communities facing similar struggles for survival and respect. The sharing of commonalities of marginalized cultures not only serves as a source of education outside of typically myopic, mainstream sources, but it also creates transnational bonds globally to the extent that practicing artists resonate with many of the original themes of (now mostly underground) Hip Hop as with many of the African American artists responsible for creating and fostering Hip Hop's powerful outlet of expression. Hip Hop's power of connectivity and culture-sharing transnationally across borders provides a key source of education to be taken seriously by academics.Keywords: culture, education, global, hip hop, mainstream music, transnational
Procedia PDF Downloads 1012073 Scanning Transmission Electron Microscopic Analysis of Gamma Ray Exposed Perovskite Solar Cells
Authors: Aleksandra Boldyreva, Alexander Golubnichiy, Artem Abakumov
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Various perovskite materials have surprisingly high resistance towards high-energy electrons, protons, and hard ionization, such as X-rays and gamma-rays. Superior radiation hardness makes a family of perovskite semiconductors an attractive candidate for single- and multijunction solar cells for the space environment and as X-ray and gamma-ray detectors. One of the methods to study the radiation hardness of different materials is by exposing them to gamma photons with high energies (above 500 keV) Herein, we have explored the recombination dynamics and defect concentration of a mixed cation mixed halide perovskite Cs0.17FA0.83PbI1.8Br1.2 with 1.74 eV bandgap after exposure to a gamma-ray source (2.5 Gy/min). We performed an advanced STEM EDX analysis to reveal different types of defects formed during gamma exposure. It was found that 10 kGy dose results in significant improvement of perovskite crystallinity and homogeneous distribution of I ions. While the absorber layer withstood gamma exposure, the hole transport layer (PTAA) as well as indium tin oxide (ITO) were significantly damaged, which increased the interface recombination rate and reduction of fill factor in solar cells. Thus, STEM analysis is a powerful technique that can reveal defects formed by gamma exposure in perovskite solar cells. Methods: Data will be collected from perovskite solar cells (PSCs) and thin films exposed to gamma ionisator. For thin films 50 μL of the Cs0.17FA0.83PbI1.8Br1.2 solution in DMF was deposited (dynamically) at 3000 rpm followed by quenching with 100 μL of ethyl acetate (dropped 10 sec after perovskite precursor) applied at the same spin-coating frequency. The deposited Cs0.17FA0.83PbI1.8Br1.2 films were annealed for 10 min at 100 °C, which led to the development of a dark brown color. For the solar cells, 10% suspension of SnO2 nanoparticles (Alfa Aesar) was deposited at 4000 rpm, followed by annealing on air at 170 ˚C for 20 min. Next, samples were introduced into a nitrogen glovebox for the deposition of all remaining layers. Perovskite film was applied in the same way as in thin films described earlier. Solution of poly-triaryl amine PTAA (Sigma Aldrich) (4 mg in chlorobenzene) was applied at 1000 rpm atop of perovskite layer. Next, 30 nm of VOx was deposited atop the PTAA layer on the whole sample surface using the physical vapor deposition (PVD) technique. Silver electrodes (100 nm) were evaporated in a high vacuum (10-6 mbar) through a shadow mask, defining the active area of each device as ~0.16 cm2. The prepared samples (thin films and solar cells) were packed in Al lamination foil inside the argon glove box. The set of samples consisted of 6 thin films and 6 solar cells, which were exposed to 6, 10, and 21 kGy (2 samples per dose) with 137Cs gamma-ray source (E = 662 keV) with a dose rate of 2.5 Gy/min. The exposed samples will be studied on a focused ion beam (FIB) on a dual-beam scanning electron microscope from ThermoFisher, the Helios G4 Plasma FIB Uxe, operating with a xenon plasma.Keywords: perovskite solar cells, transmission electron microscopy, radiation hardness, gamma irradiation
Procedia PDF Downloads 242072 Significance of Water Saving through Subsurface Drip Irrigation for Date Palm Trees
Authors: Ahmed I. Al-Amoud
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A laboratory and field study were conducted on subsurface drip irrigation systems. In the first laboratory study, eight subsurface drip irrigation lines available locally, were selected and a number of experiments were made to evaluate line hydraulic characteristics to insure it's suitability for drip irrigation design requirements and high performance to select the best for field experiments. The second study involves field trials on mature date palm trees to study the effect of subsurface drip irrigation system on the yield and water consumption of date palms, and to compare that with the traditional surface drip irrigation system. Experiments were conducted in Alwatania Agricultural Project, on 50 mature palm trees (17 years old) of Helwa type with 10 meters spacing between rows and between trees. A high efficiency subsurface line (Techline) was used based on the results of the first study. Irrigation scheduling was made through a soil moisture sensing device to ensure enough soil water levels in the soil. Experiment layouts were installed during 2001 season, measurements continued till end of 2008 season. Results have indicated that there is an increase in the yield and a considerable saving in water compared to the conventional drip irrigation method. In addition there were high increases in water use efficiency using the subsurface system. The subsurface system proves to be durable and highly efficient for irrigating date palm trees.Keywords: drip irrigation, subsurface drip irrigation, date palm trees, date palm water use, date palm yield
Procedia PDF Downloads 4332071 Establishments of an Efficient Platform for Genome Editing in Grapevine
Authors: S. Najafi, E. Bertini, M. Pezzotti, G.B. Tornielli, S. Zenoni
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Grapevine is an important agricultural fruit crop plant consumed worldwide and with a key role in the global economy. Grapevine is strongly affected by both biotic and abiotic stresses, which impact grape growth at different stages, such as during plant and berry development and pre- and post-harvest, consequently causing significant economic losses. Recently global warming has propelled the anticipation of the onset of berry ripening, determining the reduction of a grape color and increased volatilization of aroma compounds. Climate change could negatively alter the physiological characteristics of the grape and affect the berry and wine quality. Modern plant breeding can provide tools such as genome editing for improving grape resilience traits while maintaining intact the viticultural and oenological quality characteristics of the genotype. This study aims at developing a platform for genome editing application in grapevine plants with the final goal to improve berry quality, biotic, and abiotic resilience traits. We chose to directly deliver ribonucleoproteins (RNP, preassembled Cas protein and guide RNA) into plant protoplasts, and, from these cell structures, regenerate grapevine plants edited in specific selected genes controlling traits of interest. Edited plants regenerated by somatic embryogenesis from protoplasts will then be sequenced and molecularly characterized. Embryogenic calli of Sultana and Shiraz cultivars were initiated from unopened leaves of in-vitro shoot tip cultures and from stamens, respectively. Leaves were placed on NB2 medium while stamens on callus initiation medium (PIV) medium and incubated in the dark at 28 °C for three months. Viable protoplasts, tested by FDA staining, isolated from embryogenic calli were cultured by disc method at 1*105 protoplasts/ml. Mature well-shaped somatic embryos developed directly in the protoplast culture medium two months later and were transferred in the light into to shooting medium for further growth. Regenerated plants were then transferred to the greenhouse; no phenotypic alterations were observed when compared to non in-vitro cultured plants. The performed experiments allowed to established an efficient protocol of embryogenic calli production, protoplast isolation, and regeneration of the whole plant through somatic embryogenesis in both Sultana and Shiraz. Regenerated plants, through direct somatic embryogenesis deriving from a single cell, avoid the risk of chimerism during the regeneration process, therefore improving the genome editing process. As pre-requisite of genome editing, an efficient method for transfection of protoplast by yellow fluorescent protein (YFP) marker genes was also established and experiments of direct delivery of CRISPR–Cas9 ribonucleoproteins (RNPs) in protoplasts to achieve efficient DNA-free targeted mutations are in progress.Keywords: CRISPR-cas9, plant regeneration, protoplast isolation, Vitis vinifera
Procedia PDF Downloads 1502070 Development of Multilayer Capillary Copper Wick Structure using Microsecond CO₂ Pulsed Laser
Authors: Talha Khan, Surendhar Kumaran, Rajeev Nair
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The development of economical, efficient, and reliable next-generation thermal and water management systems to provide efficient cooling and water management technologies is being pursued application in compact and lightweight spacecraft. The elimination of liquid-vapor phase change-based thermal and water management systems is being done due to issues with the reliability and robustness of this technology. To achieve the motive of implementing the principle of using an innovative evaporator and condenser design utilizing bimodal wicks manufactured using a microsecond pulsed CO₂ laser has been proposed in this study. Cylin drical, multilayered capillary copper wicks with a substrate diameter of 39 mm are additively manufactured using a pulsed laser. The copper particles used for layer-by-layer addition on the substrate measure in a diameter range of 225 to 450 micrometers. The primary objective is to develop a novel, high-quality, fast turnaround, laser-based additive manufacturing process that will eliminate the current technical challenges involved with the traditional manufacturing processes for nano/micro-sized powders, like particle agglomeration. Raster-scanned, pulsed-laser sintering process has been developed to manufacture 3D wicks with controlled porosity and permeability.Keywords: liquid-vapor phase change, bimodal wicks, multilayered, capillary, raster-scanned, porosity, permeability
Procedia PDF Downloads 1912069 A Multi-Objective Gate Assignment Model Based on Airport Terminal Configuration
Authors: Seyedmirsajad Mokhtarimousavi, Danial Talebi, Hamidreza Asgari
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Assigning aircrafts’ activities to appropriate gates is one the most challenging issues in airport authorities’ multiple criteria decision making. The potential financial loss due to imbalances of demand and supply in congested airports, higher occupation rates of gates, and the existing restrictions to expand facilities provide further evidence for the need for an optimal supply allocation. Passengers walking distance, towing movements, extra fuel consumption (as a result of awaiting longer to taxi when taxi conflicts happen at the apron area), etc. are the major traditional components involved in GAP models. In particular, the total cost associated with gate assignment problem highly depends on the airport terminal layout. The study herein presents a well-elaborated literature review on the topic focusing on major concerns, applicable variables and objectives, as well as proposing a three-objective mathematical model for the gate assignment problem. The model has been tested under different concourse layouts in order to check its performance in different scenarios. Results revealed that terminal layout pattern is a significant parameter in airport and that the proposed model is capable of dealing with key constraints and objectives, which supports its practical usability for future decision making tools. Potential solution techniques were also suggested in this study for future works.Keywords: airport management, terminal layout, gate assignment problem, mathematical modeling
Procedia PDF Downloads 2292068 Enabling Cloud Adoption Based Secured Mobile Banking through Backend as a Service
Authors: P. S. Jagadeesh Kumar, S. Meenakshi Sundaram
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With the increase of prevailing non-traditional rivalry, mobile banking experiences an ever changing commercial backdrop. Substantial customer demands have established to be more intricate as customers request more expediency and superintend over their banking services. To enterprise advance and modernization in mobile banking applications, it is gradually obligatory to deeply leapfrog the scuffle using business model transformation. The dramaturgical vicissitudes taking place in mobile banking entail advanced traditions to exploit security. By reforming and transforming older back office into integrated mobile banking applications, banks can engender a supple and nimble banking environment that can rapidly respond to new business requirements over cloud computing. Cloud computing is transfiguring ecosystems in numerous industries, and mobile banking is no exemption providing services innovation, greater flexibility to respond to improved security and enhanced business intelligence with less cost. Cloud technology offer secure deployment possibilities that can provision banks in developing new customer experiences, empower operative relationship and advance speed to efficient banking transaction. Cloud adoption is escalating quickly since it can be made secured for commercial mobile banking transaction through backend as a service in scrutinizing the security strategies of the cloud service provider along with the antiquity of transaction details and their security related practices.Keywords: cloud adoption, backend as a service, business intelligence, secured mobile banking
Procedia PDF Downloads 2542067 The Role of Online Social Networks in Social Movements: Social Polarization and Violations against Social Unity and Privacy of Individuals in Turkey
Authors: Tolga Yazıcı
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As a matter of the fact that online social networks like Twitter, Facebook and MySpace have experienced an extensive growth in recent years. Social media offers individuals with a tool for communicating and interacting with one another. These social networks enable people to stay in touch with other people and express themselves. This process makes the users of online social networks active creators of content rather than being only consumers of traditional media. That’s why millions of people show strong desire to learn the methods and tools of digital content production and necessary communication skills. However, the booming interest in communication and interaction through online social networks and high level of eagerness to invent and implement the ways to participate in content production raise some privacy and security concerns. This presentation aims to open the assumed revolutionary, democratic and liberating nature of the online social media up for discussion by reviewing some recent political developments in Turkey. Firstly, the role of Internet and online social networks in mobilizing collective movements through social interactions and communications will be questioned. Secondly, some cases from Gezi and Okmeydanı Protests and also December 17-25 period will be presented in order to illustrate misinformation and manipulation in social media and violation of individual privacy through online social networks in order to damage social unity and stability contradictory to democratic nature of online social networking.Keywords: online social media networks, democratic participation, social movements, social polarization, privacy of individuals, Turkey
Procedia PDF Downloads 3412066 A Deep Learning Approach to Online Social Network Account Compromisation
Authors: Edward K. Boahen, Brunel E. Bouya-Moko, Changda Wang
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The major threat to online social network (OSN) users is account compromisation. Spammers now spread malicious messages by exploiting the trust relationship established between account owners and their friends. The challenge in detecting a compromised account by service providers is validating the trusted relationship established between the account owners, their friends, and the spammers. Another challenge is the increase in required human interaction with the feature selection. Research available on supervised learning (machine learning) has limitations with the feature selection and accounts that cannot be profiled, like application programming interface (API). Therefore, this paper discusses the various behaviours of the OSN users and the current approaches in detecting a compromised OSN account, emphasizing its limitations and challenges. We propose a deep learning approach that addresses and resolve the constraints faced by the previous schemes. We detailed our proposed optimized nonsymmetric deep auto-encoder (OPT_NDAE) for unsupervised feature learning, which reduces the required human interaction levels in the selection and extraction of features. We evaluated our proposed classifier using the NSL-KDD and KDDCUP'99 datasets in a graphical user interface enabled Weka application. The results obtained indicate that our proposed approach outperformed most of the traditional schemes in OSN compromised account detection with an accuracy rate of 99.86%.Keywords: computer security, network security, online social network, account compromisation
Procedia PDF Downloads 1192065 Effect of Printing Process on Mechanical Properties of Interface between 3D Printed Concrete Strips
Authors: Wei Chen, Jinlong Pan
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3D concrete printing technology is a novel and highly efficient construction method that holds significant promise for advancing low-carbon initiatives within the construction industry. In contrast to traditional construction practices, 3D printing offers a manual and formwork-free approach, resulting in a transformative shift in labor requirements and fabrication techniques. This transition yields substantial reductions in carbon emissions during the construction phase, as well as decreased on-site waste generation. Furthermore, when compared to conventionally printed concrete, 3D concrete exhibits mechanical anisotropy due to its layer-by-layer construction methodology. Therefore, it becomes imperative to investigate the influence of the printing process on the mechanical properties of 3D printed strips and to optimize the mechanical characteristics of these coagulated strips. In this study, we conducted three-dimensional reconstructions of printed blocks using both circular and directional print heads, incorporating various overlap distances between strips, and employed CT scanning for comprehensive analysis. Our research focused on assessing mechanical properties and micro-pore characteristics under different loading orientations. Our findings reveal that increasing the overlap degree between strips leads to enhanced mechanical properties of the strips. However, it's noteworthy that once full overlap is achieved, further increases in the degree of coincidence do not lead to a decrease in porosity between strips. Additionally, due to its superior printing cross-sectional area, the square printing head exhibited the most favorable impact on mechanical properties.Keywords: 3D printing concrete, mechanical anisotropy, micro-pore structure, printing technology
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