Search results for: MLP back propagation
1481 Generic Hybrid Models for Two-Dimensional Ultrasonic Guided Wave Problems
Authors: Manoj Reghu, Prabhu Rajagopal, C. V. Krishnamurthy, Krishnan Balasubramaniam
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A thorough understanding of guided ultrasonic wave behavior in structures is essential for the application of existing Non Destructive Evaluation (NDE) technologies, as well as for the development of new methods. However, the analysis of guided wave phenomena is challenging because of their complex dispersive and multimodal nature. Although numerical solution procedures have proven to be very useful in this regard, the increasing complexity of features and defects to be considered, as well as the desire to improve the accuracy of inspection often imposes a large computational cost. Hybrid models that combine numerical solutions for wave scattering with faster alternative methods for wave propagation have long been considered as a solution to this problem. However usually such models require modification of the base code of the solution procedure. Here we aim to develop Generic Hybrid models that can be directly applied to any two different solution procedures. With this goal in mind, a Numerical Hybrid model and an Analytical-Numerical Hybrid model has been developed. The concept and implementation of these Hybrid models are discussed in this paper.Keywords: guided ultrasonic waves, Finite Element Method (FEM), Hybrid model
Procedia PDF Downloads 4651480 Regular Laboratory Based Neonatal Simulation Program Increases Senior Clinicians’ Knowledge, Skills and Confidence Caring for Sick Neonates
Authors: Madeline Tagg, Choihoong Mui, Elizabeth Lek, Jide Menakaya
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Introduction: Simulation technology is used by neonatal teams to learn and refresh skills and gain the knowledge and confidence to care for sick neonates. In-situ simulation is considered superior to laboratory-based programmes as it closely mirrors real life situations. This study reports our experience of running regular laboratory-based simulation sessions for senior clinicians and nurses and its impact on their knowledge, skills and confidence. Methods: A before and after questionnaire survey was carried out on senior clinicians and nurses that attended a scheduled laboratory-based simulation session. Participants were asked to document their expectations before a 3-hour monthly laboratory programme started and invited to feedback their reflections at the end of the session. The session included discussion of relevant clinical guidelines, immersion in a scenario and video led debrief. The results of the survey were analysed in three skills based categories - improved, no change or a worsened experience. Results: 45 questionnaires were completed and analysed. Of these 25 (55%) were completed by consultants seven and six by nurses and trainee doctors respectively, and seven respondents were unknown. 40 (88%) rated the session overall and guideline review as good/excellent, 39 respondents (86%) rated the scenario session good/excellent and 40/45 fed back a good/excellent debrief session. 33 (73%) respondents completed the before and after questionnaire. 21/33 (63%) reflected an improved knowledge, skill or confidence in caring for sick new-bon babies, eight respondents reported no change and four fed back a worse experience after the session. Discussion: Most respondents found the laboratory based structured simulation session beneficial for their professional development. They valued equally the whole content of the programme such as guideline review and equipment training as well as the simulation and debrief sessions. Two out three participants stated their knowledge of caring for sick new-born babies had been transformed positively by the session. Sessions where simulation equipment failed or relevant staff were absent contributed to a poor educational experience. Summary: A regular structured laboratory-based simulation programme with a rich content is a credible educational resource for improving the knowledge, skills and confidence of senior clinicians caring for sick new born babies.Keywords: knowledge, laboratory based, neonates, simulation
Procedia PDF Downloads 1211479 Classification of Crisp Petri Nets
Authors: Riddhi Jangid, Gajendra Pratap Singh
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Petri nets, a formalized modeling language that was introduced back around 50-60 years, have been widely used for modeling discrete event dynamic systems and simulating their behavior. Reachability analysis of Petri nets gives many insights into a modeled system. This idea leads us to study the reachability technique and use it in the reachability problem in the state space of reachable markings. With the same concept, Crisp Boolean Petri nets were defined in which the marking vectors that are boolean are distinct in the reachability analysis of the nets. We generalize the concept and define ‘Crisp’ Petri nets that generate the marking vectors exactly once in their reachability-based analysis, not necessarily Boolean.Keywords: marking vector, n-vector, Petri nets, reachability
Procedia PDF Downloads 821478 Political Manipulation in Global Discourse
Authors: Gohar Madoyan, Kristine Harutyunyan, Gevorg Barseghyan
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It is common knowledge that linguistic manipulation is and has always been a powerful instrument of political discourse. Politicians from different countries and through centuries have successfully used linguistic means to persuade the public. Yet, this persuasion should be linguistically unobtrusive. Small changes in wording may result in a huge difference in perception by the audience. Thus, manipulation is a strategy that is mostly used to convey a certain message to the manipulators, who should be aware of the vulnerabilities of their audience and who must use them to achieve control. Political manipulation, though commonly observed in the 21st century, can easily be traced back to ancient rhetoric, which warns us to choose words carefully while addressing the audience. On the other hand, modern manipulative techniques have become more sophisticated, making use of all scientific advances.Keywords: manipulators, politics, persuasion, political discourse, linguo-stylistic analysis, rhetoric
Procedia PDF Downloads 841477 Propagation of DEM Varying Accuracy into Terrain-Based Analysis
Authors: Wassim Katerji, Mercedes Farjas, Carmen Morillo
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Terrain-Based Analysis results in derived products from an input DEM and these products are needed to perform various analyses. To efficiently use these products in decision-making, their accuracies must be estimated systematically. This paper proposes a procedure to assess the accuracy of these derived products, by calculating the accuracy of the slope dataset and its significance, taking as an input the accuracy of the DEM. Based on the output of previously published research on modeling the relative accuracy of a DEM, specifically ASTER and SRTM DEMs with Lebanon coverage as the area of study, analysis have showed that ASTER has a low significance in the majority of the area where only 2% of the modeled terrain has 50% or more significance. On the other hand, SRTM showed a better significance, where 37% of the modeled terrain has 50% or more significance. Statistical analysis deduced that the accuracy of the slope dataset, calculated on a cell-by-cell basis, is highly correlated to the accuracy of the input DEM. However, this correlation becomes lower between the slope accuracy and the slope significance, whereas it becomes much higher between the modeled slope and the slope significance.Keywords: terrain-based analysis, slope, accuracy assessment, Digital Elevation Model (DEM)
Procedia PDF Downloads 4461476 Numerical Modeling of Air Pollution with PM-Particles and Dust
Authors: N. Gigauri, A. Surmava, L. Intskirveli, V. Kukhalashvili, S. Mdivani
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The subject of our study is atmospheric air pollution with numerical modeling. In the presented article, as the object of research, there is chosen city Tbilisi, the capital of Georgia, with a population of one and a half million and a difficult terrain. The main source of pollution in Tbilisi is currently vehicles and construction dust. The concentrations of dust and PM (Particulate Matter) were determined in the air of Tbilisi and in its vicinity. There are estimated their monthly maximum, minimum, and average concentrations. Processes of dust propagation in the atmosphere of the city and its surrounding territory are modelled using a 3D regional model of atmospheric processes and an admixture transfer-diffusion equation. There were taken figures of distribution of the polluted cloud and dust concentrations in different areas of the city at different heights and at different time intervals with the background stationary westward and eastward wind. It is accepted that the difficult terrain and mountain-bar circulation affect the deformation of the cloud and its spread, there are determined time periods when the dust concentration in the city is greater than MAC (Maximum Allowable Concentration, MAC=0.5 mg/m³).Keywords: air pollution, dust, numerical modeling, PM-particles
Procedia PDF Downloads 1401475 Post-Earthquake Damage Detection Using System Identification with a Pair of Seismic Recordings
Authors: Lotfi O. Gargab, Ruichong R. Zhang
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A wave-based framework is presented for modeling seismic motion in multistory buildings and using measured response for system identification which can be utilized to extract important information regarding structure integrity. With one pair of building response at two locations, a generalized model response is formulated based on wave propagation features and expressed as frequency and time response functions denoted, respectively, as GFRF and GIRF. In particular, GIRF is fundamental in tracking arrival times of impulsive wave motion initiated at response level which is dependent on local model properties. Matching model and measured-structure responses can help in identifying model parameters and infer building properties. To show the effectiveness of this approach, the Millikan Library in Pasadena, California is identified with recordings of the Yorba Linda earthquake of September 3, 2002.Keywords: system identification, continuous-discrete mass modeling, damage detection, post-earthquake
Procedia PDF Downloads 3691474 Between an Idea and the Experiment: Dome Houses in Warsaw
Authors: Zaguła Artur, Jaruga-rozdolska Anna
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The idea of prefabricated dwellings dates back to the earliest times; however, it was during the modern era that it became one of the main thoughts that stimulated the imagination of architects. The system of prefabrication invented by Ford had inspired them to try to create a system or prototype that could become the basis for the mass 'production' of houses. The attempts made by Le Corbusier, Buckminster Fuller or Charles and Ray Eames, among others, are well known in this regard. The economic attractiveness of replicable, mass-producible houses meant that experiments in this area were undertaken in both the West and the East. Among such attempts was the project of dome-shaped houses conceived by the architect and inventor Andrzej Iwanicki and realised between 1961 and 1966 in Warsaw's Okęcie district on Ustrzycka Street.Keywords: dome houses, polish modernism, postwar modernism, modernist houses
Procedia PDF Downloads 1081473 Wavelet Based Signal Processing for Fault Location in Airplane Cable
Authors: Reza Rezaeipour Honarmandzad
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Wavelet analysis is an exciting method for solving difficult problems in mathematics, physics, and engineering, with modern applications as diverse as wave propagation, data compression, signal processing, image processing, pattern recognition, etc. Wavelets allow complex information such as signals, images and patterns to be decomposed into elementary forms at different positions and scales and subsequently reconstructed with high precision. In this paper a wavelet-based signal processing algorithm for airplane cable fault location is proposed. An orthogonal discrete wavelet decomposition and reconstruction algorithm is used to eliminate the noise in the aircraft cable fault signal. The experiment result has shown that the character of emission pulse and reflect pulse used to test the aircraft cable fault point are reserved and the high-frequency noise are eliminated by means of the proposed algorithm in this paper.Keywords: wavelet analysis, signal processing, orthogonal discrete wavelet, noise, aircraft cable fault signal
Procedia PDF Downloads 5241472 Spin-Dependent Transport Signatures of Bound States: From Finger to Top Gates
Authors: Yun-Hsuan Yu, Chi-Shung Tang, Nzar Rauf Abdullah, Vidar Gudmundsson
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Spin-orbit gap feature in energy dispersion of one-dimensional devices is revealed via strong spin-orbit interaction (SOI) effects under Zeeman field. We describe the utilization of a finger-gate or a top-gate to control the spin-dependent transport characteristics in the SOI-Zeeman influenced split-gate devices by means of a generalized spin-mixed propagation matrix method. For the finger-gate system, we find a bound state in continuum for incident electrons within the ultra-low energy regime. For the top-gate system, we observe more bound-state features in conductance associated with the formation of spin-associated hole-like or electron-like quasi-bound states around band thresholds, as well as hole bound states around the reverse point of the energy dispersion. We demonstrate that the spin-dependent transport behavior of a top-gate system is similar to that of a finger-gate system only if the top-gate length is less than the effective Fermi wavelength.Keywords: spin-orbit, zeeman, top-gate, finger-gate, bound state
Procedia PDF Downloads 2691471 Residual Modulus of Elasticity of Self-Compacting Concrete Incorporated Unprocessed Waste Fly Ash after Expose to the Elevated Temperature
Authors: Mohammed Abed, Rita Nemes, Salem Nehme
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The present study experimentally investigated the impact of incorporating unprocessed waste fly ash (UWFA) on the residual mechanical properties of self-compacting concrete (SCC) after exposure to elevated temperature. Three mixtures of SCC have been produced by replacing the cement mass by 0%, 15% and 30% of UWFA. Generally, the fire resistance of SCC has been enhanced by replacing the cement up to 15% of UWFA, especially in case of residual modulus of elasticity which considers more sensitive than other mechanical properties at elevated temperature. However, a strong linear relationship has been observed between the residual flexural strength and modulus of elasticity, where both of them affected significantly by the cracks appearance and propagation as a result of elevated temperature. Sustainable products could be produced by incorporating unprocessed waste powder materials in the production of concrete, where the waste materials, CO2 emissions, and the energy needed for processing are reduced.Keywords: self-compacting high-performance concrete, unprocessed waste fly ash, fire resistance, residual modulus of elasticity
Procedia PDF Downloads 1351470 Vibration Propagation in Structures Through Structural Intensity Analysis
Authors: Takhchi Jamal, Ouisse Morvan, Sadoulet-Reboul Emeline, Bouhaddi Noureddine, Gagliardini Laurent, Bornet Frederic, Lakrad Faouzi
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Structural intensity is a technique that can be used to indicate both the magnitude and direction of power flow through a structure from the excitation source to the dissipation sink. However, current analysis is limited to the low frequency range. At medium and high frequencies, a rotational component appear in the field, masking the energy flow and make its understanding difficult or impossible. The objective of this work is to implement a methodology to filter out the rotational components of the structural intensity field in order to fully understand the energy flow in complex structures. The approach is based on the Helmholtz decomposition. It allows to decompose the structural intensity field into rotational, irrotational, and harmonic components. Only the irrotational component is needed to describe the net power flow from a source to a dissipative zone in the structure. The methodology has been applied on academic structures, and it allows a good analysis of the energy transfer paths.Keywords: structural intensity, power flow, helmholt decomposition, irrotational intensity
Procedia PDF Downloads 1781469 Simple Multipath Compensation for Frequency Modulated Signals: A Case of Radio Frequency vs. Quadrature Baseband
Authors: Lusungu Ndovi
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Radio propagation from point-to-point is affected by the physical channel in many ways. A signal arriving at a destination travels through a number of different paths which are referred to as multi-paths. Research in this area of wireless communications has progressed well over the years with the research taking different angles of focus. By this is meant that some researchers focus on ways of reducing or eluding Multipath effects whilst others focus on ways of mitigating the effects of Multipath through compensation schemes. Baseband processing is seen as one field of signal processing that is cardinal to the advancement of software-defined radio technology. This has led to wide research into the carrying out certain algorithms at baseband. This paper considers compensating for Multipath for Frequency Modulated signals. The compensation process is carried out at Radio frequency (RF) and at Quadrature baseband (QBB) and the results are compared. Simulations are carried out using MatLab so as to show the benefits of working at lower QBB frequencies than at RF.Keywords: quadrature baseband, qadio frequency, qultipath compensation, frequency qodulation, signal processing
Procedia PDF Downloads 4811468 Disconnect between Water, Sanitation and Hygiene Related Behaviours of Children in School and Family
Authors: Rehan Mohammad
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Background: Improved Water, Sanitation and Hygiene (WASH) practices in schools ensure children’s health, well-being and cognitive performance. In India under various WASH interventions in schools, teachers, and other staff make every possible effort to educate children about personal hygiene, sanitation practices and harms of open defecation. However, once children get back to their families, they see other practicing inappropriate WASH behaviors, and they consequently start following them. This show disconnect between school behavior and family behavior, which needs to be bridged to achieve desired WASH outcomes. Aims and Objectives: The aim of this study is to assess the factors causing disconnect of WASH-related behaviors between school and the family of children. It also suggests behavior change interventions to bridge the gap. Methodology: The present study has chosen a mixed- method approach. Both quantitative and qualitative methods of data collection have been used in the present study. The purposive sampling for data collection has been chosen. The data have been collected from 20% children in each age group of 04-08 years and 09-12 years spread over three primary schools and 20% of households to which they belong to which is spread over three slum communities in south district of Delhi. Results: The present study shows that despite of several behavior change interventions at school level, children still practice inappropriate WASH behaviors due to disconnect between school and family behaviors. These behaviors show variation from one age group to another. The inappropriate WASH behaviors being practiced by children include open defecation, wrong disposal of garbage, not keeping personal hygiene, not practicing hand washing practices during critical junctures and not washing fruits and vegetables before eating. The present study has highlighted that 80% of children in the age group of 04-08 years still practice inappropriate WASH behaviors when they go back to their families after school whereas, this percentage has reduced to 40% in case of children in the age group 09-12 years. Present study uncovers association between school and family teaching which creates a huge gap between WASH-related behavioral practices. The study has established that children learn and de-learn the WASH behaviors due to the evident disconnect between behavior change interventions at schools and household level. The study has also made it clear that children understand the significance of appropriate WASH practices but owing to the disconnect the behaviors remain unsettled. The study proposes several behavior change interventions to sync the behaviors of children at school and family level to ensure children’s health, well-being and cognitive performance.Keywords: behavioral interventions, child health, family behavior, school behavior, WASH
Procedia PDF Downloads 1111467 Common Health Problems of Filipino Overseas Household Service Workers: Implications for Wellness
Authors: Veronica Ramirez
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For over 40 years now, the Philippines has been supplying Household Service Workers (HSWs) globally. As a requirement of the Philippine Overseas Employment Agency (POEA), all Filipinos applying for overseas work undergo medical examination and a certificate of good health is submitted to the foreign employer before hiring. However, there are workplace-related health problems that develop during employment such as musculoskeletal strain or injury, back pain, hypertension and other illnesses. Some workers are in good working conditions but are on call more than 12 hours per day. There are also those who experience heavy physical work with short rest periods or time off. They can also be easily exposed to disease outbreaks and epidemics. It was the objective of this study to determine the common health problems of Filipino Overseas Service Workers and analyze their implications to wellness in the workplace. Specifically, it sought to describe the work conditions of HSWs and determine the work-related factors affecting their health. It also identified the medical care they avail of and how they perceive their health and wellness as determinants of well-being. Finally, it proposes ways to promote wellness among HSWs. This study focused on physical illnesses and does not include mental problems experienced by HSWs. Using a questionnaire, primary data were gathered online and through survey of HSW rehires who were retaking Pre-Departure Orientation Seminar at recruitment agencies. The 2010 Health Benefit Availment data from the Overseas Workers Welfare Administration (OWWA) was also utilized. Descriptive analysis was employed on the data gathered. Key stakeholders in the migration industry were also interviewed. Previous research studies, reports and literature on migration and wellness were used as secondary data. The study found that Filipino overseas HSWs are vulnerable to physical injury and experience body pains such as back, hip and shoulder pain. Long hours of work, work hazards and lack of rest due to poor accommodations can aggravate their physical condition. Although health insurance and health care are available, HSWs are not aware how to avail them. On the basis of the findings, a Wellness Program can be designed that include health awareness, health care availment, occupational ergonomics, safety and health, work and leisure balance, developing emotional intelligence, anger management and spirituality.Keywords: health, household service worker, overseas, wellness
Procedia PDF Downloads 2581466 Assessment of the Effect of Ethanolic Leaf Extract of Annona squamosa L. on Den Induced Hepatocellular Carcinoma in Experimental Animals
Authors: Vanitha Varadharaj, Vijalakshmi Krishnamurthy
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Annona squamosa Linn, commonly known as Sugar apple, belonging to the family Annonaceae, is said to show varied medicinal effects, including insecticide, antiovulatory and abortifacient. The alkaloid and flavonoids present in Annona squamosa leaf has proved to have antioxidant activity. The present work has been planned to investigate the effect of ethanolic leaf extract of Annona squamosa leaf on Den Induced wistar albino rats. The study was carried out to analyze the biochemical Parmeters like Total Proteins, Bilirubin, Enzymatic and Non –Enzymatic enzymes, Marker enzymes and Tumor markers in serum and also the histopathological studies in liver is carried out in control and DEN induced rats. Supplementation of ELAS (Ethanolic Leaf Extract Of Annona squamosa) reduced the liver weight and also reduced the tumour incidence. Chemoprevention group showed near normal values of bilirubin when compared with the control rats. Total protein was decreased in the cancer bearing group and on treatment with the extract the levels of protein were restored. Both in pre and post treatment group, the activities of enzymatic antioxidants such as superoxide dismutase, catalase, and Glutathione peroxidase were increased but in pre treated animals it was more effective than post treated animals. The non- enzymatic antioxidants such as vitamin C and vitamin E were brought back to normal level significantly in post and pre treated animals. Activities of marker enzymes such as SGOT, SGPT, ALP, γ GT were significantly elevated in the serum of cancer animals and the values returned to normal after treatment with the extract suggesting the hepato protective effect of the extract. Lipid peroxide was found to be elevated in the cancer induced group. This condition was brought back to the normal in the pre and post treated animals with ELAS. Histological examination also confirmed the anti- carcinogenic potential of ELAS, Cancer induced groups had a triple fold increase in their AFP values when compared to other groups. DEN treatment increased the level of AFP expression while ELAS partially counteracted the effect of it. So the scientific validation obtained from this study may pave way to many budding scientists to find new drugs from Annona squamosa for various ailments.Keywords: annona squamosa, biochemical parmeters, cancer, leaf extract
Procedia PDF Downloads 3311465 HPA Pre-Distorter Based on Neural Networks for 5G Satellite Communications
Authors: Abdelhamid Louliej, Younes Jabrane
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Satellites are becoming indispensable assets to fifth-generation (5G) new radio architecture, complementing wireless and terrestrial communication links. The combination of satellites and 5G architecture allows consumers to access all next-generation services anytime, anywhere, including scenarios, like traveling to remote areas (without coverage). Nevertheless, this solution faces several challenges, such as a significant propagation delay, Doppler frequency shift, and high Peak-to-Average Power Ratio (PAPR), causing signal distortion due to the non-linear saturation of the High-Power Amplifier (HPA). To compensate for HPA non-linearity in 5G satellite transmission, an efficient pre-distorter scheme using Neural Networks (NN) is proposed. To assess the proposed NN pre-distorter, two types of HPA were investigated: Travelling Wave Tube Amplifier (TWTA) and Solid-State Power Amplifier (SSPA). The results show that the NN pre-distorter design presents EVM improvement by 95.26%. NMSE and ACPR were reduced by -43,66 dB and 24.56 dBm, respectively. Moreover, the system suffers no degradation of the Bit Error Rate (BER) for TWTA and SSPA amplifiers.Keywords: satellites, 5G, neural networks, HPA, TWTA, SSPA, EVM, NMSE, ACPR
Procedia PDF Downloads 911464 Rolling Contact Fatigue Failure Analysis of Ball Bearing in Gear Box
Authors: Piyas Palit, Urbi Pal, Jitendra Mathur, Santanu Das
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Bearing is an important machinery part in the industry. When bearings fail to meet their expected life the consequences are increased downtime, loss of revenue and missed the delivery. This article describes the failure of a gearbox bearing in rolling contact fatigue. The investigation consists of visual observation, chemical analysis, characterization of microstructures using optical microscopes and hardness test. The present study also considers bearing life as well as the operational condition of bearings. Surface-initiated rolling contact fatigue, leading to a surface failure known as pitting, is a life-limiting failure mode in many modern machine elements, particularly rolling element bearings. Metallography analysis of crack propagation, crack morphology was also described. Indication of fatigue spalling in the ferrography test was also discussed. The analysis suggested the probable reasons for such kind of failure in operation. This type of spalling occurred due to (1) heavier external loading condition or (2) exceeds its service life.Keywords: bearing, rolling contact fatigue, bearing life
Procedia PDF Downloads 1711463 Observation of Large-Scale Traveling Ionospheric Disturbance over Peninsular Malaysia Using GPS Receivers
Authors: Intan Izafina Idrus, Mardina Abdullah, Alina Marie Hasbi, Asnawi Husin
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This paper presents the result of large-scale traveling ionospheric disturbance (LSTID) observation during moderate magnetic storm event on 25 October 2011 with SYM-H ~ -160 nT and Kp ~ 7 over Peninsular Malaysia at equatorial region using vertical total electron content (VTEC) from the Global Positioning System (GPS) observation measurement. The propagation of the LSTID signatures in the TEC measurements over Peninsular Malaysia was also investigated using VTEC map. The LSTID was found to propagate equator-ward during this event. The results showed that the LSTID propagated with an average phase velocity of 526.41 m/s and average periods of 140 min. The occurrence of this LSTID was also found to be the subsequent effects of substorm activities in the auroral region.Keywords: Global Positioning System (GPS), large-scale traveling ionospheric disturbance (LSTID), moderate geomagnetic storm, vertical total electron content (VTEC)
Procedia PDF Downloads 2251462 Experimental Approach for Determining Hemi-Anechoic Characteristics of Engineering Acoustical Test Chambers
Authors: Santiago Montoya-Ospina, Raúl E. Jiménez-Mejía, Rosa Elvira Correa Gutiérrez
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An experimental methodology is proposed for determining hemi-anechoic characteristics of an engineering acoustic room built at the facilities of Universidad Nacional de Colombia to evaluate the free-field conditions inside the chamber. Experimental results were compared with theoretical ones in both, the source and the sound propagation inside the chamber. Acoustic source was modeled by using monopole radiation pattern from punctual sources and the image method was considered for dealing with the reflective plane of the room, that means, the floor without insulation. Finite-difference time-domain (FDTD) method was implemented to calculate the sound pressure value at every spatial point of the chamber. Comparison between theoretical and experimental data yields to minimum error, giving satisfactory results for the hemi-anechoic characterization of the chamber.Keywords: acoustic impedance, finite-difference time-domain, hemi-anechoic characterization
Procedia PDF Downloads 1631461 Cybercrime Stage Based Intervention: Through the Eyes of a Cyber Threat Actor
Authors: Jonathan W. Z. Lim, Vrizlynn L. L. Thing
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Cybercrimes are on the rise, in part due to technological advancements, as well as increased avenues of exploitation. Sophisticated threat actors are leveraging on such advancements to execute their malicious intentions. The increase in cybercrimes is prevalent, and it seems unlikely that they can be easily eradicated. A more serious concern is that the community may come to accept the notion that this will become the trend. As such, the key question revolves around how we can reduce cybercrime in this evolving landscape. In our paper, we propose to build a systematic framework through the lens of a cyber threat actor. We explore the motivation factors behind the crimes and the crime stages of the threat actors. We then formulate intervention plans so as to discourage the act of committing malicious cyber activities and also aim to integrate ex-cyber offenders back into society.Keywords: crime motivations, crime prevention, cybercrime, ex-cyber criminals
Procedia PDF Downloads 1381460 A Measurement Device of Condensing Flow Rate, an Order of MilliGrams per Second
Authors: Hee Joon Lee
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There are many difficulties in measuring a small flow rate of an order of milli grams per minute (LPM) or less using a conventional flowmeter. Therefore, a flow meter with minimal loss and based on a new concept was designed as part of this paper. A chamber was manufactured with a level transmitter and an on-off control valve. When the level of the collected condensed water reaches the top of the chamber, the valve opens to allow the collected water to drain back into the tank. To allow the water to continue to drain when the signal is lost, the valve is held open for a few seconds by a time delay switch and then closed. After an examination, the condensing flow rate was successfully measured with the uncertainty of ±5.7% of the full scale for the chamber.Keywords: chamber, condensation, flow meter, milli-grams
Procedia PDF Downloads 2811459 The Influence of Disturbances Generated by Arc Furnaces on the Power Quality
Authors: Z. Olczykowski
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The paper presents the impact of work on the electric arc furnace. Arc equipment is one of the largest receivers powered by the power system. Electric arc disturbances arising during melting process occurring in these furnaces are the cause of an abrupt change of the passive power of furnaces. Currents drawn by these devices undergo an abrupt change, which in turn cause voltage fluctuations and light flicker. The quantitative evaluation of the voltage fluctuations is now the basic criterion of assessment of an influence of unquiet receiver on the supplying net. The paper presents the method of determination of range of voltage fluctuations and light flicker at parallel operation of arc devices. The results of measurements of voltage fluctuations and light flicker indicators recorded in power supply networks of steelworks were presented, with different number of parallel arc devices. Measurements of energy quality parameters were aimed at verifying the proposed method in practice. It was also analyzed changes in other parameters of electricity: the content of higher harmonics, asymmetry, voltage dips.Keywords: power quality, arc furnaces, propagation of voltage fluctuations, disturbances
Procedia PDF Downloads 1381458 Investigation of Arson Fire Incident in Textile Garment Building Using Fire Dynamic Simulation
Authors: Mohsin Ali Shaikh, Song Weiguo, Muhammad Kashan Surahio, Usman Shahid, Rehmat Karim
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This study investigated a catastrophic arson fire incident that occurred at a textile garment building in Karachi, Pakistan. Unfortunately, a catastrophic event led to the loss of 262 lives and caused 55 severe injuries. The primary objective is to analyze the aspects of the fire incident and understand the causes of arson fire disasters. The study utilized Fire Dynamic Simulation (F.D.S) was employed to simulate fire propagation, visibility, harmful gas concentration, fire temperature, and numerical results. The analysis report has determined the specific circumstances that created the unpleasant incident in the present study. The significance of the current findings lies in their potential to prevent arson fires, improve fire safety measures, and the development of safety plans in building design. The fire dynamic simulation findings can serve as a theoretical basis for the investigation of arson fires and evacuation planning in textile garment buildings.Keywords: investigation, fire arson incident, textile garment, fire dynamic simulation (FDS)
Procedia PDF Downloads 901457 An Elegant Technique to Achieve ZCS in a Boost Converter Incorporating Complete Energy Transfer
Authors: Nagesh Vangala, Rayudu Mannam
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Soft switching has attracted the interest of various researchers constantly. Many techniques are in vogue to achieve soft switching (ZVS and/or ZCS) in Boost converters. These techniques utilize an auxiliary switch to incorporate the ZCS/ZVS. Such schemes require additional control circuit and induce complexity in design. This paper proposes an elegant fly back approach which guarantees zero current switching of the main Switch without the need for any additional active device. A simple flyback transformer scheme is implemented which absorbs the initial turn ON energy (or the Reverse recovery energy of Boost diode) and delivers to the output.Keywords: boost converter, complete energy transfer, flyback, zero current switching
Procedia PDF Downloads 3981456 Investigation of the Relationship between Digital Game Playing, Internet Addiction and Perceived Stress Levels in University Students
Authors: Sevim Ugur, Cemile Kutmec Yilmaz, Omer Us, Sevdenur Koksaldi
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Aim: This study aims to investigate the effect of digital game playing and Internet addiction on perceived stress levels in university students. Method: The descriptive study was conducted through face-to-face interview method with a total of 364 university students studying at Aksaray University between November 15 and December 30, 2017. The research data were collected using personal information form, a questionnaire to determine the characteristics of playing digital game, the Internet addiction scale and the perceived stress scale. In the evaluation of the data, Mann-Whitney U test was used for two-group comparison of the sample with non-normal distribution, Kruskal-Wallis H-test was used in the comparison of more than two groups, and the Spearman correlation test was used to determine the relationship between Internet addiction and the perceived stress level. Results: It was determined that the mean age of the students participated in the study was 20.13 ± 1.7 years, 67.6% was female, 35.7% was sophomore, and 62.1% had an income 500 TL or less. It was found that 83.5% of the students use the Internet every day and 70.6% uses the Internet for 5 hours or less per day. Of the students, 12.4% prefers digital games instead of spending time outdoors, 8% plays a game as the first activity in leisure time, 12.4% plays all day, 15.7% feels anger when he/she is prevented from playing, 14.8% prefers playing games to get away from his/her problems, 23.4% had his/her school achievement affected negatively because of game playing, and 8% argues with family members due to the time spent for gaming. Students who play games on the computer for a long time were found to feel back pain (30.8%), headache (28.6%), insomnia (26.9%), dryness and pain in the eyes (26.6%), pain in the wrist (21.2%), feeling excessive tension and anger (16.2%), humpback (12.9), vision loss (9.6%) and pain in the wrist and fingers (7.4%). In our study, students' Internet addiction scale mean score was found to be 45.47 ± 16.1 and mean perceived stress scale score was 28.56 ± 2.7. A significant and negative correlation (p=0.037) was found between the total score of the Internet addiction scale and the total score of the perceived stress scale (r=-0.110). Conclusion: It was found in the study that Internet addiction and perceived stress of the students were at a moderate level and that there was a negative correlation between Internet addiction and perceived stress levels. Internet addiction was found to increase with the increasing perceived stress levels of students, and students were found to have health problems such as back pain, dryness in the eyes, pain, insomnia, headache, and humpback. Therefore, it is recommended to inform students about different coping methods other than spending time on the Internet to cope with the stress they perceive.Keywords: digital game, internet addiction, student, stress level
Procedia PDF Downloads 2881455 Coaxial Helix Antenna for Microwave Coagulation Therapy in Liver Tissue Simulations
Authors: M. Chaichanyut, S. Tungjitkusolmun
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This paper is concerned with microwave (MW) ablation for a liver cancer tissue by using helix antenna. The antenna structure supports the propagation of microwave energy at 2.45 GHz. A 1½ turn spiral catheter-based microwave antenna applicator has been developed. We utilize the three-dimensional finite element method (3D FEM) simulation to analyze where the tissue heat flux, lesion pattern and volume destruction during MW ablation. The configurations of helix antenna where Helix air-core antenna and Helix Dielectric-core antenna. The 3D FEMs solutions were based on Maxwell and bio-heat equations. The simulation protocol was power control (10 W, 300s). Our simulation result, both helix antennas have heat flux occurred around the helix antenna and that can be induced the temperature distribution similar (teardrop). The region where the temperature exceeds 50°C the microwave ablation was successful (i.e. complete destruction). The Helix air-core antenna and Helix Dielectric-core antenna, ablation zone or axial ratios (Widest/length) were respectively 0.82 and 0.85; the complete destructions were respectively 4.18 cm³ and 5.64 cm³.Keywords: liver cancer, Helix antenna, finite element, microwave ablation
Procedia PDF Downloads 3091454 The Impact of Recurring Events in Fake News Detection
Authors: Ali Raza, Shafiq Ur Rehman Khan, Raja Sher Afgun Usmani, Asif Raza, Basit Umair
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Detection of Fake news and missing information is gaining popularity, especially after the advancement in social media and online news platforms. Social media platforms are the main and speediest source of fake news propagation, whereas online news websites contribute to fake news dissipation. In this study, we propose a framework to detect fake news using the temporal features of text and consider user feedback to identify whether the news is fake or not. In recent studies, the temporal features in text documents gain valuable consideration from Natural Language Processing and user feedback and only try to classify the textual data as fake or true. This research article indicates the impact of recurring and non-recurring events on fake and true news. We use two models BERT and Bi-LSTM to investigate, and it is concluded from BERT we get better results and 70% of true news are recurring and rest of 30% are non-recurring.Keywords: natural language processing, fake news detection, machine learning, Bi-LSTM
Procedia PDF Downloads 221453 Verification and Application of Finite Element Model Developed for Flood Routing in Rivers
Authors: A. L. Qureshi, A. A. Mahessar, A. Baloch
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Flood wave propagation in river channel flow can be enunciated by nonlinear equations of motion for unsteady flow. However, it is difficult to find analytical solution of these complex non-linear equations. Hence, verification of the numerical model should be carried out against field data and numerical predictions. This paper presents the verification of developed finite element model applying for unsteady flow in the open channels. The results of a proposed model indicate a good matching with both Preissmann scheme and HEC-RAS model for a river reach of 29 km at both sites (15 km from upstream and at downstream end) for discharge hydrographs. It also has an agreeable comparison with the Preissemann scheme for the flow depth (stage) hydrographs. The proposed model has also been applying to forecast daily discharges at 400 km downstream from Sukkur barrage, which demonstrates accurate model predictions with observed daily discharges. Hence, this model may be utilized for predicting and issuing flood warnings about flood hazardous in advance.Keywords: finite element method, Preissmann scheme, HEC-RAS, flood forecasting, Indus river
Procedia PDF Downloads 5041452 Finite Element Simulation for Preliminary Study on Microorganism Detection System
Authors: Muhammad Rosli Abdullah, Noor Hasmiza Harun
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A microorganism detection system has a potential to be used with the advancement in a biosensor development. The detection system requires an optical sensing system, microfluidic device and biological reagent. Although, the biosensors are available in the market, a label free and a lab-on-chip approach will promote a flexible solution. As a preliminary study of microorganism detection, three mechanisms such as Total Internal Reflection (TIR), Micro Fluidic Channel (MFC) and magnetic-electric field propagation were study and simulated. The objective are to identify the TIR angle, MFC parabolic flow and the wavelength for the microorganism detection. The simulation result indicates that evanescent wave is achieved when TIR angle > 42°, the corner and centre of a parabolic velocity are 0.02 m/s and 0.06 m/s respectively, and a higher energy distribution of a perfect electromagnetic scattering with dipole resonance radiation occurs at 500 nm. This simulation is beneficial to determine the components of the microorganism detection system that does not rely on classical microbiological, immunological and genetic methods which are laborious, time-consuming procedures and confined to specialized laboratories with expensive instrumentation equipment.Keywords: microorganism, microfluidic, total internal reflection, lab on chip
Procedia PDF Downloads 277