Search results for: large deviation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7956

Search results for: large deviation

7116 Characteristics of Elastic Tracked-Crawler Based on Worm-Rack Mechanism

Authors: Jun-ya Nagase

Abstract:

There are many pipes such as a water pipe and a gas pipe in a chemical plant and house. It is possible to prevent accidents by these inspections. However, many pipes are very narrow and it is difficult for people to inspect directly. Therefore, development of a robot that can move in narrow pipe is necessary. A wheel movement type robot, a snake-like robot and a multi-leg robot are all described in the relevant literature as pipe inspection robots that are currently studied. Among them, the tracked crawler robot can travel by traversing uneven ground flexibly with a crawler belt attached firmly to the ground surface. Although conventional crawler robots have high efficiency and/or high ground-covering ability, they require a comparatively large space to move. In this study, a cylindrical crawler robot based on worm-rack mechanism, which does not need large space to move and which has high ground-covering ability, is proposed. Experiments have demonstrated smooth operation and a forward movement of the robot by application of voltage to the motor. In addition, performance tests show that it can propel itself in confined spaces. This paper reports the structure, drive mechanism, prototype, and experimental evaluation.

Keywords: tracked-crawler, pipe inspection robot, worm-rack mechanism, amoeba locomotion

Procedia PDF Downloads 430
7115 [Keynote]: No-Trust-Zone Architecture for Securing Supervisory Control and Data Acquisition

Authors: Michael Okeke, Andrew Blyth

Abstract:

Supervisory Control And Data Acquisition (SCADA) as the state of the art Industrial Control Systems (ICS) are used in many different critical infrastructures, from smart home to energy systems and from locomotives train system to planes. Security of SCADA systems is vital since many lives depend on it for daily activities and deviation from normal operation could be disastrous to the environment as well as lives. This paper describes how No-Trust-Zone (NTZ) architecture could be incorporated into SCADA Systems in order to reduce the chances of malicious intent. The architecture is made up of two distinctive parts which are; the field devices such as; sensors, PLCs pumps, and actuators. The second part of the architecture is designed following lambda architecture, which is made up of a detection algorithm based on Particle Swarm Optimization (PSO) and Hadoop framework for data processing and storage. Apache Spark will be a part of the lambda architecture for real-time analysis of packets for anomalies detection.

Keywords: industrial control system (ics, no-trust-zone (ntz), particle swarm optimisation (pso), supervisory control and data acquisition (scada), swarm intelligence (SI)

Procedia PDF Downloads 343
7114 Efficient High Fidelity Signal Reconstruction Based on Level Crossing Sampling

Authors: Negar Riazifar, Nigel G. Stocks

Abstract:

This paper proposes strategies in level crossing (LC) sampling and reconstruction that provide high fidelity signal reconstruction for speech signals; these strategies circumvent the problem of exponentially increasing number of samples as the bit-depth is increased and hence are highly efficient. Specifically, the results indicate that the distribution of the intervals between samples is one of the key factors in the quality of signal reconstruction; including samples with short intervals do not improve the accuracy of the signal reconstruction, whilst samples with large intervals lead to numerical instability. The proposed sampling method, termed reduced conventional level crossing (RCLC) sampling, exploits redundancy between samples to improve the efficiency of the sampling without compromising performance. A reconstruction technique is also proposed that enhances the numerical stability through linear interpolation of samples separated by large intervals. Interpolation is demonstrated to improve the accuracy of the signal reconstruction in addition to the numerical stability. We further demonstrate that the RCLC and interpolation methods can give useful levels of signal recovery even if the average sampling rate is less than the Nyquist rate.

Keywords: level crossing sampling, numerical stability, speech processing, trigonometric polynomial

Procedia PDF Downloads 141
7113 Crack Width Evaluation for Flexural RC Members with Axial Tension

Authors: Sukrit Ghorai

Abstract:

Proof of controlling crack width is a basic condition for securing suitable performance in serviceability limit state. The cracking in concrete can occur at any time from the casting of time to the years after the concrete has been set in place. Most codes struggle with offering procedure for crack width calculation. There is lack in availability of design charts for designers to compute crack width with ease. The focus of the study is to utilize design charts and parametric equations in calculating crack width with minimum error. The paper contains a simplified procedure to calculate crack width for reinforced concrete (RC) sections subjected to bending with axial tensile force following the guidelines of Euro code [DS EN-1992-1-1 & DS EN-1992-1-2]. Numerical examples demonstrate the application of the suggested procedure. Comparison with parallel analytical tools support the validity of result and show the percentage deviation of crack width in both the procedures. The technique is simple, user-friendly and ready to evolve for a greater spectrum of section sizes and materials.

Keywords: concrete structures, crack width calculation, serviceability limit state, structural design, bridge engineering

Procedia PDF Downloads 382
7112 Platform Development for Vero Cell Culture on Microcarriers Using Dissociation-Reassociation Method

Authors: Thanunthon Bowornsakulwong, Charukorn Charukarn, Franck Courtes, Panit Kitsubun, Lalintip Horcharoen

Abstract:

Vero cell is a continuous cell line that is widely used for the production of viral vaccines. However, due to its adherent characteristic, scaling up strategy in large-scale production remains complicated and thus limited. Consequently, suspension-like Vero cell culture processes based on microcarriers have been introduced and employed while also providing increased surface area per volume unit. However, harvesting Vero cells from microcarriers is a huge challenge due to difficulties in cells detaching, lower recovery yield, time-consuming and dissociation agent carry-over. To overcome these problems, we developed a dissociation-association platform technology for detaching and re-attaching cells during subculturing from microcarriers to microcarriers, which will be conveniently applied to seed trains strategies in large scale bioreactors. Herein, Hillex-2 was used to culture Vero cells in serum-containing media using spinner flasks as a scale-down model. The overall confluency of cells on microcarriers was observed using inverted microscope, and the sample cells were daily detached in order to obtain the kinetics data. The metabolites consumption and by-products formation were determined by Nova Biomedical BioprofileFlex.

Keywords: dissociation-reassociation, microcarrier, scale up, Vero cell

Procedia PDF Downloads 132
7111 Consumer Behavior and Marketing Mixed Factor Effect on Consumer Decision Making for Independent Movies Presented in Lido Cinema

Authors: Pongsawee Supanonth

Abstract:

This study aims to investigate the consumer behavior and marketing mixed factor affect on consumer decision making for independent movies presented in Lido cinema. The research method will use quantitative research, data was collected by questionnaires distributed to the audience in the Lido cinema for 400 sample by accidental sampling technique. Data was analyzed by descriptive statistic including percentage, mean, standard deviation and inferential statistic including independent t-test for hypothesis testing. The results showed that marketing mixed factors affecting consumer decision-making for Independent movies presented in Lido cinema by gender as different as less than the 0.05 significance level, it was found that the kind of movie ,quality of theater ,price of ticket, facility of watching movies, staff services and promotion of Lido cinema respectively had a vital influence on their attention and response which makes the advertisement more attractive is in harmony with the research hypotheses also.

Keywords: consumer behavior, marketing mixed factor, resonance, consumer decision making, Lido cinema

Procedia PDF Downloads 309
7110 Scalable Systolic Multiplier over Binary Extension Fields Based on Two-Level Karatsuba Decomposition

Authors: Chiou-Yng Lee, Wen-Yo Lee, Chieh-Tsai Wu, Cheng-Chen Yang

Abstract:

Shifted polynomial basis (SPB) is a variation of polynomial basis representation. SPB has potential for efficient bit-level and digit-level implementations of multiplication over binary extension fields with subquadratic space complexity. For efficient implementation of pairing computation with large finite fields, this paper presents a new SPB multiplication algorithm based on Karatsuba schemes, and used that to derive a novel scalable multiplier architecture. Analytical results show that the proposed multiplier provides a trade-off between space and time complexities. Our proposed multiplier is modular, regular, and suitable for very-large-scale integration (VLSI) implementations. It involves less area complexity compared to the multipliers based on traditional decomposition methods. It is therefore, more suitable for efficient hardware implementation of pairing based cryptography and elliptic curve cryptography (ECC) in constraint driven applications.

Keywords: digit-serial systolic multiplier, elliptic curve cryptography (ECC), Karatsuba algorithm (KA), shifted polynomial basis (SPB), pairing computation

Procedia PDF Downloads 360
7109 Toward an Understanding of the Neurofunctional Dissociation between Animal and Tool Concepts: A Graph Theoretical Analysis

Authors: Skiker Kaoutar, Mounir Maouene

Abstract:

Neuroimaging studies have shown that animal and tool concepts rely on distinct networks of brain areas. Animal concepts depend predominantly on temporal areas while tool concepts rely on fronto-temporo-parietal areas. However, the origin of this neurofunctional distinction for processing animal and tool concepts remains still unclear. Here, we address this question from a network perspective suggesting that the neural distinction between animals and tools might reflect the differences in their structural semantic networks. We build semantic networks for animal and tool concepts derived from Mc Rae and colleagues’s behavioral study conducted on a large number of participants. These two networks are thus analyzed through a large number of graph theoretical measures for small-worldness: centrality, clustering coefficient, average shortest path length, as well as resistance to random and targeted attacks. The results indicate that both animal and tool networks have small-world properties. More importantly, the animal network is more vulnerable to targeted attacks compared to the tool network a result that correlates with brain lesions studies.

Keywords: animals, tools, network, semantics, small-world, resilience to damage

Procedia PDF Downloads 546
7108 Photo-Fenton Decolorization of Methylene Blue Adsolubilized on Co2+ -Embedded Alumina Surface: Comparison of Process Modeling through Response Surface Methodology and Artificial Neural Network

Authors: Prateeksha Mahamallik, Anjali Pal

Abstract:

In the present study, Co(II)-adsolubilized surfactant modified alumina (SMA) was prepared, and methylene blue (MB) degradation was carried out on Co-SMA surface by visible light photo-Fenton process. The entire reaction proceeded on solid surface as MB was embedded on Co-SMA surface. The reaction followed zero order kinetics. Response surface methodology (RSM) and artificial neural network (ANN) were used for modeling the decolorization of MB by photo-Fenton process as a function of dose of Co-SMA (10, 20 and 30 g/L), initial concentration of MB (10, 20 and 30 mg/L), concentration of H2O2 (174.4, 348.8 and 523.2 mM) and reaction time (30, 45 and 60 min). The prediction capabilities of both the methodologies (RSM and ANN) were compared on the basis of correlation coefficient (R2), root mean square error (RMSE), standard error of prediction (SEP), relative percent deviation (RPD). Due to lower value of RMSE (1.27), SEP (2.06) and RPD (1.17) and higher value of R2 (0.9966), ANN was proved to be more accurate than RSM in order to predict decolorization efficiency.

Keywords: adsolubilization, artificial neural network, methylene blue, photo-fenton process, response surface methodology

Procedia PDF Downloads 252
7107 Random Matrix Theory Analysis of Cross-Correlation in the Nigerian Stock Exchange

Authors: Chimezie P. Nnanwa, Thomas C. Urama, Patrick O. Ezepue

Abstract:

In this paper we use Random Matrix Theory to analyze the eigen-structure of the empirical correlations of 82 stocks which are consistently traded in the Nigerian Stock Exchange (NSE) over a 4-year study period 3 August 2009 to 26 August 2013. We apply the Marchenko-Pastur distribution of eigenvalues of a purely random matrix to investigate the presence of investment-pertinent information contained in the empirical correlation matrix of the selected stocks. We use hypothesised standard normal distribution of eigenvector components from RMT to assess deviations of the empirical eigenvectors to this distribution for different eigenvalues. We also use the Inverse Participation Ratio to measure the deviation of eigenvectors of the empirical correlation matrix from RMT results. These preliminary results on the dynamics of asset price correlations in the NSE are important for improving risk-return trade-offs associated with Markowitz’s portfolio optimization in the stock exchange, which is pursued in future work.

Keywords: correlation matrix, eigenvalue and eigenvector, inverse participation ratio, portfolio optimization, random matrix theory

Procedia PDF Downloads 342
7106 Customer Relationship Management on Social Media Affecting Brand Loyalty of Siam Commercial Bank in Bangkok

Authors: Charawee Butbumrung

Abstract:

The purpose of this research was to study customer relationship management on social media affecting brand loyalty of Siam Commercial Bank in Bangkok. The statistics used in data analysis were frequency, mean, standard deviation, and Pearson’s correlation coefficient based on social science statistic program. The result of the study found that the majority of the respondents were female, 37–47 years old of age, bachelor degree of education and monthly income between 10,001 and 15,000 Baht. In addition, customer relationship management in the overall and by each aspect of formulating, maintaining, and extending the customer relationship had a high score. Furthermore, the result of hypothesis testing showed that the difference of the customer’s age, education, occupation, average monthly income had the difference in brand loyalty with the statistical significance level of 0.05 and customer relationship management had related with brand loyalty in the same direction with the low level of statistical significance 0.05.

Keywords: brand loyalty, customer relationship management, Siam Commercial bank, social media

Procedia PDF Downloads 245
7105 Conducting Computational Physics Laboratory Course Using Cloud Storage Space

Authors: Ajay Wadhwa

Abstract:

A Laboratory course on computational physics is different from the conventional lab course on other topics of physics like Mechanics, Heat, Optics, etc. because it involves active participation of the teacher as well as one-to-one interaction between teacher and the student. The course content requires the teacher to teach programming language as well as numerical methods along with their applications in physics. The task becomes more daunting when about 90% of the students in the class have no previous experience of any programming language. In the presented work, we have described a methodology for conducting the computational physics course by using the Google Drive and Dropitto.me cloud storage services. We have evaluated the performance in a class of sixty students by dividing them equally into four groups. One of the groups was made the peer group on whom the presented methodology was tested. The other groups were taught by using conventional method of classroom lectures. In order to assess our methodology, we analyzed the performance of students in four class tests. A study of certain statistical parameters like the mean, standard deviation, and Z-test hypothesis revealed that the cyber methodology based on cloud storage is more efficient than the conventional method of teaching.

Keywords: computational Physics, Z-test hypothesis, cloud storage, Google drive

Procedia PDF Downloads 298
7104 Digitalization: The Uneven Geography of Information and Communication Technology (ICTS) CTSoss Four Major States in India

Authors: Sanchari Mukhopadhyay

Abstract:

Today, almost the entire realm of human activities are becoming increasingly dependent on the power of information, where through ICTs it is now possible to cater distances and avail various services at a few clicks. In principle, ICTs are thus expected to blur location-specific differences and affiliations of development and bring in an inclusive society at the wake of globalization. However, eventually researchers and policy analysts realized that ICTs are also generating inequality in spite of the hope for an integrated world and widespread social well-being. Regarding this unevenness, location plays a major role as often ICT development is seen to be concentrated into pockets, leaving behind large tracks as underprivileged. Thus, understanding the spatial pattern of ICT development and distribution is significant in relation to exploring the extent to which ICTs are fulfilling the promises or reassuring the existing divisions. In addition, it is also profoundly crucial to investigate how regions are connecting and competing both locally and globally. The focus of the research paper is to evaluate the spatial structure of ICT led development in India. Thereby, it attempts to understand the state level (four selected states) pattern of ICT penetration, the pattern of diffusion across districts with respect to large urban centres and the rural-urban disparity of technology adoption. It also tries to assess the changes in access dynamisms of ICTs as one move away from a large metropolitan city towards the periphery. In brief, the analysis investigates into the tendency towards the uneven growth of development through the identification of the core areas of ICT advancement within the country and its diffusion from the core to the periphery. In order to assess the level of ICT development and rural-urban disparity across the districts of selected states, two indices named ICT Development Index and Rural-Urban Digital Divide Index have been constructed. The study mostly encompasses the latest Census (2011) of the country and TRAI (Telecom Regulatory Authority of India) in some cases.

Keywords: ICT development, diffusion, core-periphery, digital divide

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7103 Particle Separation Using Individually-Controlled Magnetic Soft Artificial Cilia

Authors: Yau-Luen Ng, Nathan Banka, Santosh Devasia

Abstract:

In this paper, a method based on soft artificial cilia is introduced to separate particles based on size and mass. In nature, cilia are used for fluid propulsion in the mammalian circulatory system, as well as for swimming and size-selective particle entrainment for feeding in microorganisms. Inspired by biological cilia, an array of artificial cilia was fabricated using Polydimethylsiloxane (PDMS) to simulate the actual motion. A row of four individually-controlled magnetic artificial cilia in a semi-circular channel are actuated by the magnetic fields from four permanent magnets. Each cilium is a slender rectangular cantilever approximately 13mm long made from a composite of PDMS and carbonyl iron particles. A time-varying magnetic force is achieved by periodically varying the out-of-plane distance from the permanent magnets to the cilia, resulting in large-amplitude deflections of the cilia that can be used to drive fluid motion. Previous results have shown that this system of individually-controlled magnetic cilia can generate effective mixing flows; the purpose of the present work is to apply the individual cilia control to a particle separation task. Based on the observed beating patterns of cilia arrays in nature, the experimental beating patterns were selected as a metachronal wave, in which a fixed phase lead or lag is imposed between adjacent cilia. Additionally, the beating frequency was varied. For each set of experimental parameters, the channel was filled with water and polyethylene microspheres introduced at the center of the cilia array. Two types of particles were used: large red microspheres with density 0.9971 g/cm³ and 850-1000 μm avg. diameter, and small blue microspheres with density 1.06 g/cm³ and diameter 30 μm. At low beating frequencies, all particles were propelled in the mean flow direction. However, the large particles were observed to reverse directions above about 4.8 Hz, whereas reversal of the small particle transport direction did not occur until 6 Hz. Between these two transition frequencies, the large and small particles can be separated as they move in opposite directions. The experimental results show that selecting an appropriate cilia beating pattern can lead to selective transport of neutrally-buoyant particles based on their size. Importantly, the separation threshold can be chosen dynamically by adjusting the actuation frequency. However, further study is required to determine the range of particle sizes that can be effectively separated for a given system geometry.

Keywords: magnetic cilia, particle separation, tunable separation, soft actutors

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7102 Towards a Reinvented Cash Management Function: Mobilising Innovative Advances for Enhanced Performance and Optimised Cost Management: Insights from Large Moroccan Companies in the Casablanca-Settat Region

Authors: Badrane Nohayla, Bamousse Zineb

Abstract:

Financial crises, exchange rate volatility, fluctuations in commodity prices, increased competitive pressures, and environmental issues are all threats that businesses face. In light of these diverse challenges, proactive, agile, and innovative cash management becomes an indispensable financial shield, allowing companies to thrive despite the adverse conditions of the global environment. In the same spirit, uncertainty, turbulence, volatility, and competitiveness continue to disrupt economic environments, compelling companies to swiftly master innovative breakthroughs that provide added value. In such a context, innovation emerges as a catalytic vector for performance, aiming to reduce costs, strengthen growth, and ultimately ensure the sustainability of Moroccan companies in the national arena. Moreover, innovation in treasury management promises to be one of the key pillars of financial stability, enabling companies to navigate the tumultuous waters of a globalized environment. Therefore, the objective of this study is to better understand the impact of innovative treasury management on cost optimization and, by extension, performance improvement. To elucidate this relationship, we conducted an exploratory qualitative study with 20 large Moroccan companies operating in the Casablanca-Settat region. The results highlight that innovation at the heart of treasury management is a guarantee of sustainability against the risks of failure and stands as a true pivot of the performance of Moroccan companies, an important parameter of their financial balance and a catalytic vector of their growth in the national economic landscape. In this regard, the present study aims to explore the extent to which innovation at the core of the treasury function serves as an indispensable tool for boosting performance while optimising costs in large Moroccan companies.

Keywords: innovative cash management, artificial intelligence, financial performance, risk management, cost savings

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7101 Development of Intelligent Construction Management System Using Web-Camera Image and 3D Object Image

Authors: Hyeon-Seung Kim, Bit-Na Cho, Tae-Woon Jeong, Soo-Young Yoon, Leen-Seok Kang

Abstract:

Recently, a construction project has been large in the size and complicated in the site work. The web-cameras are used to manage the construction site of such a large construction project. They can be used for monitoring the construction schedule as compared to the actual work image of the planned work schedule. Specially, because the 4D CAD system that the construction appearance is continually simulated in a 3D CAD object by work schedule is widely applied to the construction project, the comparison system between the real image of actual work appearance by web-camera and the simulated image of planned work appearance by 3D CAD object can be an intelligent construction schedule management system (ICON). The delayed activities comparing with the planned schedule can be simulated by red color in the ICON as a virtual reality object. This study developed the ICON and it was verified in a real bridge construction project in Korea. To verify the developed system, a web-camera was installed and operated in a case project for a month. Because the angle and zooming of the web-camera can be operated by Internet, a project manager can easily monitor and assume the corrective action.

Keywords: 4D CAD, web-camera, ICON (intelligent construction schedule management system), 3D object image

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7100 Large-Scale Photovoltaic Generation System Connected to HVDC Grid with Centralized High Voltage and High Power DC/DC Converter

Authors: Xinke Huang, Huan Wang, Lidong Guo, Changbin Ju, Runbiao Liu, Shanshan Meng, Yibo Wang, Honghua Xu

Abstract:

Large-scale photovoltaic (PV) generation system connected to HVDC grid has many advantages compared to its counterpart of AC grid. DC connection can solve many problems that AC connection faces, such as the grid-connection and power transmission, and DC connection is the tendency. DC/DC converter as the most important device in the system has become one of the hot spots recently. The paper proposes a centralized DC/DC converter which uses Boost Full Bridge Isolated DC/DC Converter(BFBIC) topology and combination through input parallel output series(IPOS) method to improve power capacity and output voltage to match with the HVDC grid voltage. Meanwhile, it adopts input current sharing control strategy to realize input current and output voltage balance. A ±30kV/1MW system is modeled in MATLAB/SIMULINK, and a downscaled ±10kV/200kW DC/DC converter platform is built to verify the proposed topology and control strategy.

Keywords: photovoltaic generation, cascaded dc/dc converter, galvanic isolation, high-voltage, direct current (HVDC)

Procedia PDF Downloads 441
7099 Use of the Gas Chromatography Method for Hydrocarbons' Quality Evaluation in the Offshore Fields of the Baltic Sea

Authors: Pavel Shcherban, Vlad Golovanov

Abstract:

Currently, there is an active geological exploration and development of the subsoil shelf of the Kaliningrad region. To carry out a comprehensive and accurate assessment of the volumes and degree of extraction of hydrocarbons from open deposits, it is necessary to establish not only a number of geological and lithological characteristics of the structures under study, but also to determine the oil quality, its viscosity, density, fractional composition as accurately as possible. In terms of considered works, gas chromatography is one of the most capacious methods that allow the rapid formation of a significant amount of initial data. The aspects of the application of the gas chromatography method for determining the chemical characteristics of the hydrocarbons of the Kaliningrad shelf fields are observed in the article, as well as the correlation-regression analysis of these parameters in comparison with the previously obtained chemical characteristics of hydrocarbon deposits located on the land of the region. In the process of research, a number of methods of mathematical statistics and computer processing of large data sets have been applied, which makes it possible to evaluate the identity of the deposits, to specify the amount of reserves and to make a number of assumptions about the genesis of the hydrocarbons under analysis.

Keywords: computer processing of large databases, correlation-regression analysis, hydrocarbon deposits, method of gas chromatography

Procedia PDF Downloads 156
7098 Ageing, the Reality, and Its Gender Dimension

Authors: Forhana Rahman Noor, Shafia Jannat Khanam

Abstract:

The image of old age in Bangladesh is associated with graying of hair, wrinkling of skin, with poor physical health, and decreased ability to work. The common expression “bura hoechi”, to be aged, means to be limited in terms of performing economically productive activities, known as ‘work’. For ‘old-old’ age, there is a saying, “uthan akhon onek dure”, which literally means “even the courtyard is like a very distant place (for an old person).” Traditionally, Bengali society had a structure caring the life of older people. It was common in the joint families of Bangladeshi culture. The situation has been changing. Complexities of the societies with growing rapid urbanization are influencing the traditional respects and caring structure of the elderly persons and facing social challenges. Bangladesh is projected to have 10 percent of its population of age 60 years and above in the year 2025. The ageing process is expected to accelerate in the next century, mainly because the large cohorts born in 1950s and 1960s respectively will be joining the ranks of 60 years and over during this period. The decline in mortality, particularly at young ages, also means that a higher proportion of the large cohorts will survive to old age. The country does not have enough policy or strategy to face this upcoming challenge for the aged persons which needs immediate attention.

Keywords: ageing, gender, dimension, elderly population, Bangladesh

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7097 Internal DC Short-Circuit Fault Analysis and Protection for VSI of Wind Power Generation Systems

Authors: Mehdi Radmehr, Amir Hamed Mashhadzadeh, Mehdi Jafari

Abstract:

Traditional HVDC systems are tough to DC short circuits as they are current regulated with a large reactance connected in series with cables. Multi-terminal DC wind farm topologies are attracting increasing research attempt. With AC/DC converters on the generator side, this topology can be developed into a multi-terminal DC network for wind power collection, which is especially suitable for large-scale offshore wind farms. For wind farms, the topology uses high-voltage direct-current transmission based on voltage-source converters (VSC-HVDC). Therefore, they do not suffer from over currents due to DC cable faults and there is no over current to react to. In this study, the multi-terminal DC wind farm topology is introduced. Then, possible internal DC faults are analyzed according to type and characteristic. Fault over current expressions are given in detail. Under this characteristic analysis, fault detection and detailed protection methods are proposed. Theoretical analysis and PSCAD/EMTDC simulations are provided.

Keywords: DC short circuits, multi-terminal DC wind farm topologies, HVDC transmission based on VSC, fault analysis

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7096 Approach for the Mathematical Calculation of the Damping Factor of Railway Bridges with Ballasted Track

Authors: Andreas Stollwitzer, Lara Bettinelli, Josef Fink

Abstract:

The expansion of the high-speed rail network over the past decades has resulted in new challenges for engineers, including traffic-induced resonance vibrations of railway bridges. Excessive resonance-induced speed-dependent accelerations of railway bridges during high-speed traffic can lead to negative consequences such as fatigue symptoms, distortion of the track, destabilisation of the ballast bed, and potentially even derailment. A realistic prognosis of bridge vibrations during high-speed traffic must not only rely on the right choice of an adequate calculation model for both bridge and train but first and foremost on the use of dynamic model parameters which reflect reality appropriately. However, comparisons between measured and calculated bridge vibrations are often characterised by considerable discrepancies, whereas dynamic calculations overestimate the actual responses and therefore lead to uneconomical results. This gap between measurement and calculation constitutes a complex research issue and can be traced to several causes. One major cause is found in the dynamic properties of the ballasted track, more specifically in the persisting, substantial uncertainties regarding the consideration of the ballasted track (mechanical model and input parameters) in dynamic calculations. Furthermore, the discrepancy is particularly pronounced concerning the damping values of the bridge, as conservative values have to be used in the calculations due to normative specifications and lack of knowledge. By using a large-scale test facility, the analysis of the dynamic behaviour of ballasted track has been a major research topic at the Institute of Structural Engineering/Steel Construction at TU Wien in recent years. This highly specialised test facility is designed for isolated research of the ballasted track's dynamic stiffness and damping properties – independent of the bearing structure. Several mechanical models for the ballasted track consisting of one or more continuous spring-damper elements were developed based on the knowledge gained. These mechanical models can subsequently be integrated into bridge models for dynamic calculations. Furthermore, based on measurements at the test facility, model-dependent stiffness and damping parameters were determined for these mechanical models. As a result, realistic mechanical models of the railway bridge with different levels of detail and sufficiently precise characteristic values are available for bridge engineers. Besides that, this contribution also presents another practical application of such a bridge model: Based on the bridge model, determination equations for the damping factor (as Lehr's damping factor) can be derived. This approach constitutes a first-time method that makes the damping factor of a railway bridge calculable. A comparison of this mathematical approach with measured dynamic parameters of existing railway bridges illustrates, on the one hand, the apparent deviation between normatively prescribed and in-situ measured damping factors. On the other hand, it is also shown that a new approach, which makes it possible to calculate the damping factor, provides results that are close to reality and thus raises potentials for minimising the discrepancy between measurement and calculation.

Keywords: ballasted track, bridge dynamics, damping, model design, railway bridges

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7095 Liver Transplantation after Downstaging with Electrochemotherapy of Large Hepatocellular Carcinoma and Portal Vein Tumor Thrombosis: A Case Report

Authors: Luciano Tarantino, Emanuele Balzano, Aurelio Nasto

Abstract:

S.R. 53 years. January 2009: HCV-related cirrhosis, Child-Pugh A5 class, EGDS no aesophageal Varices. No important comorbidities. Treated with PEG-IFN+Ribavirin (march-november 2009) with subsequent sustained virologic response. HCVRNA absent overtime. October 2016 :CT detected small HCC nodule in the VIII segment (diam.=12 mm). Treated with US guided RF-ablation. November 2016 CT: complete necrosis. Unfortunately, the patient dropped out US and CT follow-up controls.September 2018: asthenia and weight loss. CT showed a large tumor infiltrating V-VII-VI segments and complete PVTT of right portal vein and its branches . Surgical Consultation excluded indication to Liver resection and OLT . 23 october 2018: ECT of a large peri-hilar area of the tumor including the PVTT. 1 and 3 months post-treatment CT showed complete necrosis and retraction of the thrombus and residual viable tumor in the peripheral portion of the right lobe . Therefor, the patient was reevaluated for OLT and considered eligible in waiting list . March 2019: CT showed no perihilar or portal vein recurrence and distant progression in the right lobe . March 2019 : Trans-arterial-Radio-therapy (TARE) of the right lobe. Post-treatment CT demonstrated no perihilar or portal vein recurrence and extensive necrosis of the residual tumor . December 2019: CT demonstrated several recurrences of HCC infiltrating the VI and VII segment . Howewer no recurrence was observed at hepatic hilum and in portal vessels . Therefore, on February 2020 the patient received OLT. At 44 months follow-up, no complication or recurrence or liver disfunction have been observed.

Keywords: hepatocellular carcinoma, portal vein tumor thrombosis, interventional ultrasound, liver tumor ablation, liver transplantation

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7094 Traditional Values and Their Adaptation in Social Housing Design: Towards a New Typology and Establishment of 'Airhouse' Standard in Malaysia

Authors: Mohd Firrdhaus Mohd Sahabuddin, Cristina Gonzalez-Longo

Abstract:

Large migration from rural areas to urban areas like Kuala Lumpur has led to some implications for economic, social and cultural development. This high population has placed enormous demand on the existing housing stocks, especially for low-income groups. However, some issues arise, one of which is overheated indoor air temperature. This problem contributes to the high-energy usage that forces huge sums of money to be spent on cooling the house by using mechanical equipment. Therefore, this study focuses on thermal comfort in social housing, and incorporates traditional values into its design to achieve a certain measurement of natural ventilation in a house. From the study, the carbon emission and energy consumption for an air-conditioned house is 67%, 66% higher than a naturally ventilated house. Therefore, this research has come up with a new typology design, which has a large exposed wall area and full-length openings on the opposite walls to increase cross ventilation. At the end of this research, the measurement of thermal comfort for a naturally ventilated building called ‘AirHouse’ has been identified.

Keywords: tropical architecture, natural ventilation, passive design, AirHouse, social housing design

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7093 The Role of Intermediaries in E-Government Adoption in India: Bridging the Digital Divide

Authors: Rajiv Kumar, Amit Sachan, Arindam Mukherjee

Abstract:

Despite the transparency and benefits of e-government, and its potential to serve citizens better, there is low diffusion and adoption of e-government services in India. Limited access to computer and internet, lack of computer and internet skills, low trust in technology, and risk associated in using e-government services are major hindrances in e-government adoption in India. Despite a large number of citizens belonging to the non-adopter category, the government has made some services mandatory to be accessed online where citizens have no other choice. Also despite the digital divide, a large number of citizens prefer online access to government services. In such cases intermediaries like common service centers, internet café and services agents’ roles are significant for accessing e-government services. Hence research is needed to explore this. The study aims to investigate the role of intermediaries in online access to public services by citizens. Qualitative research methodology using semi-structured interview was used. The results show that intermediaries play an important role in bridging the digital divide. The study also highlights on what circumstances citizens are taking help of these intermediaries. The study then highlights its limitations and discusses scope for future study.

Keywords: adoption, digital divide, e-government, India, intermediaries

Procedia PDF Downloads 291
7092 Data Augmentation for Automatic Graphical User Interface Generation Based on Generative Adversarial Network

Authors: Xulu Yao, Moi Hoon Yap, Yanlong Zhang

Abstract:

As a branch of artificial neural network, deep learning is widely used in the field of image recognition, but the lack of its dataset leads to imperfect model learning. By analysing the data scale requirements of deep learning and aiming at the application in GUI generation, it is found that the collection of GUI dataset is a time-consuming and labor-consuming project, which is difficult to meet the needs of current deep learning network. To solve this problem, this paper proposes a semi-supervised deep learning model that relies on the original small-scale datasets to produce a large number of reliable data sets. By combining the cyclic neural network with the generated countermeasure network, the cyclic neural network can learn the sequence relationship and characteristics of data, make the generated countermeasure network generate reasonable data, and then expand the Rico dataset. Relying on the network structure, the characteristics of collected data can be well analysed, and a large number of reasonable data can be generated according to these characteristics. After data processing, a reliable dataset for model training can be formed, which alleviates the problem of dataset shortage in deep learning.

Keywords: GUI, deep learning, GAN, data augmentation

Procedia PDF Downloads 182
7091 Assembly Solution for Modular Buildings: Development of a Plug-In Self-Locking Device Designed for Light-Framed Structures

Authors: Laurence Picard, André Bégin-Drolet, Pierre Blanchet

Abstract:

The prefabricated construction industry has been operating in North America for several years now and differs from traditional construction by its much shorter project timelines, lower costs, and increased build quality. Faced with the global housing crisis, prefabrication should be the first choice for erecting buildings quickly and at a low cost. However, the reality is quite different; manufacturers focus their operations mainly on single-home construction. This is explained by the lack of a suitable and efficient assembly solution for erecting large-scale buildings. Indeed, it is difficult to maintain the coveted advantages of prefabrication with a laborious on-site assembly and a colossal load of additional operations such as the installation of fasteners and the internal finishing. In the desire to maximize the benefits of prefabrication and make it a smart choice even for large buildings, an automated connection solution is developed. The plug-in self-locking device was developed accordingly to the product design phases: on-site observations, the definition of the problem and product requirements, solution generation, prototyping, fabricating and testing.

Keywords: assembly solution, automation, construction productivity, modular connection, modular buildings, plug-in device, self-lock mechanism

Procedia PDF Downloads 166
7090 Analysis of Diabetes Patients Using Pearson, Cost Optimization, Control Chart Methods

Authors: Devatha Kalyan Kumar, R. Poovarasan

Abstract:

In this paper, we have taken certain important factors and health parameters of diabetes patients especially among children by birth (pediatric congenital) where using the above three metrics methods we are going to assess the importance of each attributes in the dataset and thereby determining the most highly responsible and co-related attribute causing diabetics among young patients. We use cost optimization, control chart and Spearmen methodologies for the real-time application of finding the data efficiency in this diabetes dataset. The Spearmen methodology is the correlation methodologies used in software development process to identify the complexity between the various modules of the software. Identifying the complexity is important because if the complexity is higher, then there is a higher chance of occurrence of the risk in the software. With the use of control; chart mean, variance and standard deviation of data are calculated. With the use of Cost optimization model, we find to optimize the variables. Hence we choose the Spearmen, control chart and cost optimization methods to assess the data efficiency in diabetes datasets.

Keywords: correlation, congenital diabetics, linear relationship, monotonic function, ranking samples, pediatric

Procedia PDF Downloads 254
7089 Comparative Impact Analysis of Factors Affecting Renewable Energy Integrated and Conventional Energy Sources In Smart Grids Using MATPOWER

Authors: Sodiq Onawale, Xin Wang

Abstract:

Integrating renewable energy sources (RES) alongside conventional energy sources (NRES) in the grid has introduced challenges that highlight the need for a detailed analysis of various performance factors. Factors such as active and reactive power losses, voltage deviation, transmission line loading, power factor, fast voltage stability index, and capacity factor require careful evaluation to understand their impact on grid performance. In this study, MATPOWER’s optimization tools are used to model both NRES and a combined NRES + RES setup. The analysis compares the performance of each configuration across these factors. Findings indicate that integrating RES with NRES generally enhances performance across most of the analyzed factors compared to using NRES alone. The insights from this study offer valuable guidance for grid operators and policymakers, aiding in the balanced integration of RES with NRES to optimize smart grid performance and resilience.

Keywords: smart grid, impact analysis, renewable energy integration, FVSI, transmission line loading

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7088 Preconcentration and Determination of Cyproheptadine in Biological Samples by Hollow Fiber Liquid Phase Microextraction Coupled with High Performance Liquid Chromatography

Authors: Sh. Najari Moghadam, M. Qomi, F. Raofie, J. Khadiv

Abstract:

In this study, a liquid phase microextraction by hollow fiber (HF-LPME) combined with high performance liquid chromatography-UV detector was applied to preconcentrate and determine trace levels of Cyproheptadine in human urine and plasma samples. Cyproheptadine was extracted from 10 mL alkaline aqueous solution (pH: 9.81) into an organic solvent (n-octnol) which was immobilized in the wall pores of a hollow fiber. Then, it was back-extracted into an acidified aqueous solution (pH: 2.59) located inside the lumen of the hollow fiber. This method is simple, efficient and cost-effective. It is based on pH gradient and differences between two aqueous phases. In order to optimize the HF-LPME, some affecting parameters including the pH of donor and acceptor phases, the type of organic solvent, ionic strength, stirring rate, extraction time and temperature were studied and optimized. Under optimal conditions enrichment factor, limit of detection (LOD) and relative standard deviation (RSD(%), n=3) were up to 112, 15 μg.L−1 and 2.7, respectively.

Keywords: biological samples, cyproheptadine, hollow fiber, liquid phase microextraction

Procedia PDF Downloads 285
7087 Electrochemical Behavior and Cathodic Stripping Voltammetric Determination of Dianabol Steroid in Urine at Bare Glassy Carbon Paste Electrode

Authors: N. Al-Orfi, M. S. El-Shahawi, A. S. Bashammakh

Abstract:

The electrochemical response of glassy carbon electrode (GCE) for the sensitive and selective determination of dianabol steroid (DS) in phosphate, Britton-Robinson (B-R) and HEPES buffers of pH 2.0 - 11, 2.0 - 11 and 6.2 - 8.0, respectively using cyclic voltammetry (CV) and differential pulse- adsorptive cathodic stripping voltammetry (DP-CSV) at bare GCE was studied. The dependence of the CV response of the developed cathodic peak potential (Ep, c), peak current (ip, c) and the current function (ip, c / υ1/2) on the scan rate (υ) at the bare GCE revealed the occurrence of electrode coupled chemical reaction of EC type mechanism. The selectivity of the proposed method was assessed in the presence of high concentrations of major interfering species e.g. uric acid, ascorbic acid, citric acid, glucose, fructose, sucrose, starch and ions Na+, K+, PO4-3, NO3- and SO42-. The recovery of the method was not significant where t(critical)=2.20 > texp=1.81-1.93 at 95% confidence. The analytical application of the sensor for the quantification of DS in biological fluids as urine was investigated. The results were demonstrated as recovery percentages in the range 95±2.5-97±4.7% with relative standard deviation (RSD) of 0.5-1.5%.

Keywords: dianabol, determination, modified electrode, urine

Procedia PDF Downloads 271