Search results for: wavelength measurement.
411 Curved Rectangular Patch Array Antenna Using Flexible Copper Sheet for Small Missile Application
Authors: Jessada Monthasuwan, Charinsak Saetiaw, Chanchai Thongsopa
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This paper presents the development and design of the curved rectangular patch arrays antenna for small missile application. This design uses a 0.1mm flexible copper sheet on the front layer and back layer, and a 1.8mm PVC substrate on a middle layer. The study used a small missile model with 122mm diameter size with speed 1.1 Mach and frequency range on ISM 2.4 GHz. The design of curved antenna can be installation on a cylindrical object like a missile. So, our proposed antenna design will have a small size, lightweight, low cost and simple structure. The antenna was design and analysis by a simulation result from CST microwave studio and confirmed with a measurement result from a prototype antenna. The proposed antenna has a bandwidth covering the frequency range 2.35-2.48 GHz, the return loss below -10 dB and antenna gain 6.5 dB. The proposed antenna can be applied with a small guided missile effectively.
Keywords: Rectangular path arrays, small missile antenna.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2931410 Using Machine Learning Techniques for Autism Spectrum Disorder Analysis and Detection in Children
Authors: Norah Alshahrani, Abdulaziz Almaleh
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Autism Spectrum Disorder (ASD) is a condition related to issues with brain development that affects how a person recognises and communicates with others which results in difficulties with interaction and communication socially and it is constantly growing. Early recognition of ASD allows children to lead safe and healthy lives and helps doctors with accurate diagnoses and management of conditions. Therefore, it is crucial to develop a method that will achieve good results and with high accuracy for the measurement of ASD in children. In this paper, ASD datasets of toddlers and children have been analyzed. We employed the following machine learning techniques to attempt to explore ASD: Random Forest (RF), Decision Tree (DT), Na¨ıve Bayes (NB) and Support Vector Machine (SVM). Then feature selection was used to provide fewer attributes from ASD datasets while preserving model performance. As a result, we found that the best result has been provided by SVM, achieving 0.98% in the toddler dataset and 0.99% in the children dataset.
Keywords: Autism Spectrum Disorder, ASD, Machine Learning, ML, Feature Selection, Support Vector Machine, SVM.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 599409 Research on Urban Point of Interest Generalization Method Based on Mapping Presentation
Authors: Chengming Li, Yong Yin, Peipei Guo, Xiaoli Liu
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Without taking account of the attribute richness of POI (point of interest) data and spatial distribution limited by roads, a POI generalization method considering both attribute information and spatial distribution has been proposed against the existing point generalization algorithm merely focusing on overall information of point groups. Hierarchical characteristic of urban POI information expression has been firstly analyzed to point out the measurement feature of the corresponding hierarchy. On this basis, an urban POI generalizing strategy has been put forward: POIs urban road network have been divided into three distribution pattern; corresponding generalization methods have been proposed according to the characteristic of POI data in different distribution patterns. Experimental results showed that the method taking into account both attribute information and spatial distribution characteristics of POI can better implement urban POI generalization in the mapping presentation.
Keywords: POI, Road network, spatial information expression, selection method, distribution pattern.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1039408 Design of a Dual Polarized Resonator Antenna for Mobile Communication System
Authors: N. Fhafhiem, P. Krachodnok, R. Wongsan
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This paper proposes the development and design of double layer metamaterials based on electromagnetic band gap (EBG) rods as a superstrate of a resonator antenna to enhance required antenna characteristics for the mobile base station. The metallic rod type metamaterial can partially reflect wave of a primary radiator. The antenna was designed and analyzed by a simulation result from CST Microwave Studio and designed technique could be confirmed by a measurement results from prototype antenna that agree with simulation results. The results indicate that the antenna can also generate a dual polarization by using a 45˚ oriented curved strip dipole located at the center of the reflector plane with double layer superstrate. It can be used to simplify the feed system of an antenna. The proposed antenna has a bandwidth covering the frequency range of 1920 – 2200 MHz, the gain of the antenna increases up to 14.06 dBi. In addition, an interesting sectoral 60˚ pattern is presented in horizontal plane.
Keywords: Metamaterial, electromagnetic band gap, dual polarization, resonator antenna.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2534407 Characteristics of Suspended Solids Removal by Electrocoagulation
Authors: C. Phalakornkule, W. Worachai, T. Satitayut
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The electrochemical coagulation of a kaolin suspension was investigated at the currents of 0.06, 0.12, 0.22, 0.44, 0.85 A (corresponding to 0.68, 1.36, 2.50, 5.00, 9.66 mA·cm-2, respectively) for the contact time of 5, 10, 20, 30, and 50 min. The TSS removal efficiency at currents of 0.06 A, 0.12 A and 0.22 A increased with the amount of iron generated by the sacrificial anode, while the removal efficiencies did not increase proportionally with the amount of iron generated at the currents of 0.44 and 0.85 A, where electroflotation was clearly observed. Zeta potential measurement illustrated the presence of the highly positive charged particles created by sorption of highly charged polymeric metal hydroxyl species onto the negative surface charged kaolin particles at both low and high applied currents. The disappearance of the individual peaks after certain contact times indicated the attraction between these positive and negative charged particles causing agglomeration. It was concluded that charge neutralization of the individual species was not the only mechanism operating in the electrocoagulation process at any current level, but electrostatic attraction was likely to co-operate or mainly operate.Keywords: Coagulation, Electrocoagulation, Electrostatics, Suspended solids, Zeta potential
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2718406 Thermal Expansion Coefficient and Young’s Modulus of Silica-Reinforced Epoxy Composite
Authors: Hyu Sang Jo, Gyo Woo Lee
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In this study, the evaluation of thermal stability of the micrometer-sized silica particle reinforced epoxy composite was carried out through the measurement of thermal expansion coefficient and Young’s modulus of the specimens. For all the specimens in this study from the baseline to those containing 50 wt% silica filler, the thermal expansion coefficients and the Young’s moduli were gradually decreased down to 20% and increased up to 41%, respectively. The experimental results were compared with fillervolume- based simple empirical relations. The experimental results of thermal expansion coefficients correspond with those of Thomas’s model which is modified from the rule of mixture. However, the measured result for Young’s modulus tends to be increased slightly. The differences in increments of the moduli between experimental and numerical model data are quite large.
Keywords: Thermal Stability, Silica-Reinforced, Epoxy Composite, Coefficient of Thermal Expansion, Empirical Model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4829405 Electrical Characteristics of Biomodified Electrodes using Nonfaradaic Electrochemical Impedance Spectroscopy
Authors: Yusmeeraz Yusof, Yoshiyuki Yanagimoto, Shigeyasu Uno, Kazuo Nakazato
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We demonstrate a nonfaradaic electrochemical impedance spectroscopy measurement of biochemically modified gold plated electrodes using a two-electrode system. The absence of any redox indicator in the impedance measurements provide more precise and accurate characterization of the measured bioanalyte at molecular resolution. An equivalent electrical circuit of the electrodeelectrolyte interface was deduced from the observed impedance data of saline solution at low and high concentrations. The detection of biomolecular interactions was fundamentally correlated to electrical double-layer variation at modified interface. The investigations were done using 20mer deoxyribonucleic acid (DNA) strands without any label. Surface modification was performed by creating mixed monolayer of the thiol-modified single-stranded DNA and a spacer thiol (mercaptohexanol) by a two-step self-assembly method. The results clearly distinguish between the noncomplementary and complementary hybridization of DNA, at low frequency region below several hundreds Hertz.
Keywords: Biosensor, electrical double-layer, impedance spectroscopy, label free DNA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3088404 Permanent Magnet Synchronous Generator – Unsymmetrical Point Operation
Authors: P. Pistelok
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The article presents the concept of an electromagnetic circuit generator with permanent magnets mounted on the surface rotor core designed for single phase work. Computation field-circuit model was shown. The spectrum of time course of voltages in the idle work was presented. The cross section with graphically presentation of magnetic induction in particular parts of electromagnetic circuits was presented. Distribution of magnetic induction at the rated load point for each phase was shown. The time course of voltages and currents for each phases for rated power were displayed. An analysis of laboratory results and measurement of load characteristics of the generator was discussed. The work deals with three electromagnetic circuits of generators with permanent magnet where output voltage characteristics versus rated power were expressed.
Keywords: Permanent magnet generator, permanent magnets, vibration, course of torque, single phase work, asymmetrical three phase work.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2376403 Equivalent Field Calculation to Irregular Symmetric and Asymmetric Photon Fields
Authors: N. Chegeni, M. J. Tahmasebi Birgani
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Equivalent fields are frequently used for central axis depth-dose calculations of rectangular and irregular shaped photon beam. Since most of the proposed models to calculate the equivalent square field, are dosimetry-based, a simple physical-based method to calculate the equivalent square field size was used as the basis of this study. The table of the sides of the equivalent square for rectangular fields was constructed and then compared with the well-known tables of BJR and Venselaar with the average relative error percentage of 2.5±2.5 % and 1.5±1.5 % respectively. To evaluate the accuracy of this method, the PDDs were measured for some special irregular symmetric and asymmetric treatment fields and their equivalent squares for Siemens Primus Plus linear accelerator for both energies 6 and 18MV. The mean relative differences of PDDs measurement for these fields and their equivalent square was approximately 1% or less. As a result, this method can be employed to calculate equivalent field not only for rectangular fields but also for any irregular symmetric or asymmetric field.
Keywords: Equivalent field, asymmetric field, irregular field, multi leaf collimators.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5547402 Methods for Better Assessment of Fatigue and Deterioration in Bridges and Other Steel or Concrete Constructions
Authors: J. Menčík, B. Culek, Jr., L. Beran, J. Mareš
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Large metal and concrete structures suffer by various kinds of deterioration, and accurate prediction of the remaining life is important. This paper informs about two methods for its assessment. One method, suitable for steel bridges and other constructions exposed to fatigue, monitors the loads and damage accumulation using information systems for the operation and the finite element model of the construction. In addition to the operation load, the dead weight of the construction and thermal stresses can be included into the model. The second method is suitable for concrete bridges and other structures, which suffer by carbonatation and other degradation processes, driven by diffusion. The diffusion constant, important for the prediction of future development, can be determined from the depth-profile of pH, obtained by pH measurement at various depths. Comparison with measurements on real objects illustrates the suitability of both methods.
Keywords: Bridges, carbonatation, concrete, diagnostics, fatigue, life prediction, monitoring, railway, simulation, structures.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2013401 Assessment of Pollution of the Rustavi City’s Atmosphere with Microaerosols
Authors: N. Gigauri, A. Surmava
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According to observational data, experimental measurements and numerical modelling, the pollution of one of the industrial centers of Georgia, Rustavi City’s atmosphere with micro aerosols are assessed. Monthly, daily and hourly changes of the concentrations of PM2.5 and PM10 in the city atmosphere are analyzed. It is accepted that PM2.5 concentrations are always lower than PM10 concentrations, but their change curve is the same. In addition, it has been noted that the maximum concentrations of particles in the atmosphere of Rustavi city will be reached at any part of the day, which is determined by the total impact of the traffic flow and industrial facilities. Through numerical modelling, the influence of background western light air, gentle and fresh breeze on the distribution of particulate matter in the atmosphere was calculated. Calculations showed that background light air and gentle breeze lead to an increase the concentrations of microaerosols in the city's atmosphere, while fresh breeze contributes to the dispersion of dusty clouds. As a result, the level of dust in the city is decreasing, but the distribution area is expanding.
Keywords: Air pollution, numerical modeling, experimental measurement, PM2.5, PM10.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 165400 Experimental Characterization of Anisotropic Mechanical Properties of Textile Woven Fabric
Authors: Rym Zouari, Sami Ben Amar, Abdelwaheb Dogui
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This paper presents an experimental characterization of the anisotropic mechanical behavior of 4 textile woven fabrics with different weaves (Twill 3, Plain, Twill4 and Satin 4) by off-axis tensile testing. These tests are applied according seven directions oriented by 15° increment with respect to the warp direction. Fixed and articulated jaws are used. Analysis of experimental results is done through global (Effort/Elongation curves) and local scales. Global anisotropy was studied from the Effort/Elongation curves: shape, breaking load (Frup), tensile elongation (EMT), tensile energy (WT) and linearity index (LT). Local anisotropy was studied from the measurement of strain tensor components in the central area of the specimen as a function of testing orientation and effort: longitudinal strain ɛL, transverse strain ɛT and shearing ɛLT. The effect of used jaws is also analyzed.
Keywords: Anisotropy, Off-axis tensile test, strain fields, Textile woven fabric.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1886399 Inflammatory Markers in the Blood and Chronic Periodontitis
Authors: Saimir Heta, Ilma Robo, Nevila Alliu, Tea Meta
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Background: Plasma levels of inflammatory markers are the expression of the infectious wastes of existing periodontitis, as well as of existing inflammation everywhere in the body. Materials and Methods: The study consists of the clinical part of the measurement of inflammatory markers of 23 patients diagnosed with chronic periodontitis and the recording of parental periodontal parameters of patient periodontal status: hemorrhage index and probe values, before and 7-10 days after non-surgical periodontal treatment. Results: The level of fibrinogen drops according to the categorization of disease progression, active and passive, with the biggest % (18%-30%) at the fluctuation 10-20 mg/d. Fluctuations in fibrinogen level according to the age of patients in the range 0-10 mg/dL under 40 years and over 40 years was 13%-26%, in the range 10-20 mg/dL was 26%-22%, in the 20-40 mg/dL was 9%-4%. Conclusions: Non-surgical periodontal treatment significantly reduces the level of non-inflammatory markers in the blood. Oral health significantly reduces the potential source for periodontal bacteria, with the potential of promoting thromboembolism, through interaction between thrombocytes.
Keywords: Chronic periodontitis, atherosclerosis, risk factor, inflammatory markers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 563398 Adsorption of Phenolic Compounds on Activated Carbon DSAC36-24
Authors: Khaoula Hidouri, Ali Benhmidene, Bechir Chouachi, Dhananjay R. Mishra, Ammar Houas
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Activated carbon DSAC36-24 iy is adsorbent materials, characterized by a specific surface area of 548.13 m²g⁻¹. Their manufacture uses the natural raw materials like the nucleus of dates. In this study the treatment is done in two stages: A chemical treatment by H3PO4 followed by a physical treatment under nitrogen for 1 hour then under stream of CO2 for 24 hours. A characterization of the various parameters was determined such as the measurement of the specific surface area, determination of pHPZC, bulk density, iodine value. The study of the adsorption of organic molecules (hydroquinone, paranitrophenol, 2,4-dinitrophenol, 2,4,6-trinitrophenol) indicates that the adsorption phenomena are essentially due to the van der Waals interaction. In the case of organic molecules carrying the polar substituents, the existence of hydrogen bonds is also proved by the donor-acceptor forces. The study of the pH effect was done with modeling by different models (Langmuir, Freundlich, Langmuir-Freundlich, Redlich-Peterson), a kinetic treatment is also followed by the application of Lagergren, Weber, Macky.
Keywords: DSAC36-24, organic molecule, adsoprtion ishoterms, adsorption kinetics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 894397 Interaction of Building Stones with Inorganic Water-Soluble Salts
Authors: Z. Pavlík, J. Žumár, M. Pavlíková, R. Černý
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Interaction of inorganic water-soluble salts and building stones is studied in the paper. Two types of sandstone and one type of spongillite as representatives of materials used in historical masonry are subjected to experimental testing. Within the performed experiments, measurement of moisture and chloride concentration profiles is done in order to get input data for computational inverse analysis. Using the inverse analysis, moisture diffusivity and chloride diffusion coefficient of investigated materials are accessed. Additionally, the effect of salt presence on water vapor storage is investigated using dynamic vapor sorption device. The obtained data represents valuable information for restoration of historical masonry and give evidence on the performance of studied stones in contact with water soluble salts.
Keywords: Moisture and chloride transport, sandstone, spongillite, moisture diffusivity, chloride diffusion coefficient.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1831396 Improvement of Photoluminescence Uniformity of Porous Silicon by using Stirring Anodization Process
Authors: Jia-Chuan Lin, Meng-Kai Hsu, Hsi-Ting Hou, Sin-Hong Liu
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The electrolyte stirring method of anodization etching process for manufacturing porous silicon (PS) is reported in this work. Two experimental setups of nature air stirring (PS-ASM) and electrolyte stirring (PS-ESM) are employed to clarify the influence of stirring mechanisms on electrochemical etching process. Compared to traditional fabrication without any stirring apparatus (PS-TM), a large plateau region of PS surface structure is obtained from samples with both stirring methods by the 3D-profiler measurement. Moreover, the light emission response is also improved by both proposed electrolyte stirring methods due to the cycling force in electrolyte could effectively enhance etch-carrier distribution while the electrochemical etching process is made. According to the analysis of statistical calculation of photoluminescence (PL) intensity, lower standard deviations are obtained from PS-samples with studied stirring methods, i.e. the uniformity of PL-intensity is effectively improved. The calculated deviations of PL-intensity are 93.2, 74.5 and 64, respectively, for PS-TM, PS-ASM and PS-ESM.Keywords: Porous Silicon, Photoluminescence, Uniformity Carrier Stirring Method
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1826395 A Conceptual Framework on Review of E-Service Quality in Banking Industry
Authors: Vivek Agrawal, Vikas Tripathi, Nitin Seth
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E-service quality plays a significant role to achieve success or failure in any organization, offering services online. It will increase the competition among the organizations, to attract the customers on the basis of the quality of service provided by the organization. Better e-service quality will enhance the relationship with customers and their satisfaction. So the measurement of eservice quality is very important but it is a complex process due to the complex nature of services. Literature predicts that there is a lack of universal definition of e-service quality. The e-service quality measures in banking have great importance in achieving high customer base. This paper proposes a conceptual model for measuring e-service quality in Indian Banking Industry. Nine dimensions reliability, ease of use, personalization, security and trust, website aesthetic, responsiveness, contact and fulfillment had been identified. The results of this paper may help to develop a proper scale to measure the e-service quality in Indian Banking Industry, which may assist to maintain and improve the performance and effectiveness of e-service quality to retain customers.
Keywords: Banking, Service Quality, e-service quality, Dimensions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5496394 Inter-Phase Magnetic Coupling Effects on Sensorless SR Motor Control
Authors: N. H. Mvungi
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Control of commutation of switched reluctance (SR) motor has been an area of interest for researchers for sometime now with mixed successes in addressing the inherent challenges. New technologies, processing schemes and methods have been adopted to make sensorless SR drive a reality. There are a number of conceptual, offline, analytical and online solutions in literature that have varying complexities and achieved equally varying degree of robustness and accuracies depending on the method used to address the challenges and the SR drive application. Magnetic coupling is one such challenge when using active probing techniques to determine rotor position of a SR motor from stator winding. This paper studies the effect of back-of-core saturation on the detected rotor position and presents results on measurement made on a 4- phase SR motor. The results shows that even for a four phase motor which is excited one phase at a time and using the electrically opposite phase for active position probing, the back-of-core saturation effects should not be ignored.Keywords: Sensorless, SR motor, saturation effects, detection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1190393 Evaluating Hurst Parameters and Fractal Dimensions of Surveyed Dataset of Tailings Dam Embankment
Authors: I. Yakubu, Y. Y. Ziggah, C. Yeboah
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In the mining environment, tailings dam embankment is among the hazards and risk areas. The tailings dam embankment could fail and result to damages to facilities, human injuries or even fatalities. Periodic monitoring of the dam embankment is needed to help assess the safety of the tailings dam embankment. Artificial intelligence techniques such as fractals can be used to analyse the stability of the monitored dataset from survey measurement techniques. In this paper, the fractal dimension (D) was determined using D = 2-H. The Hurst parameters (H) of each monitored prism were determined by using a time domain of rescaled range programming in MATLAB software. The fractal dimensions of each monitored prism were determined based on the values of H. The results reveal that the values of the determined H were all within the threshold of 0 ≤ H ≤ 1 m. The smaller the H, the bigger the fractal dimension is. Fractal dimension values ranging from 1.359 x 10-4 m to 1.8843 x 10-3 m were obtained from the monitored prisms on the based on the tailing dam embankment dataset used. The ranges of values obtained indicate that the tailings dam embankment is stable.Keywords: Hurst parameter, fractal dimension, tailings dam embankment, surveyed dataset.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 759392 Characteristics of Ozone Generated from Dielectric Barrier Discharge Plasma Actuators
Authors: R. Osada, S. Ogata, T. Segawa
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Dielectric barrier discharge plasma actuators (DBD-PAs) have been developed for active flow control devices. However, it is necessary to reduce ozone produced by DBD toward practical applications using DBD-PAs. In this study, variations of ozone concentration, flow velocity, power consumption were investigated by changing exposed electrodes of DBD-PAs. Two exposed electrode prototypes were prepared: span-type with exposed electrode width of 0.1 mm, and normal-type with width of 5 mm. It was found that span-type shows lower power consumption and higher flow velocity than that of normal-type at Vp-p = 4.0-6.0 kV. Ozone concentration of span-type higher than normal-type at Vp-p = 4.0-8.0 kV. In addition, it was confirmed that catalyst located in downstream from the exposed electrode can reduce ozone concentration between 18 and 42% without affecting the induced flow.Keywords: Dielectric barrier discharge plasma actuators, ozone diffusion, PIV measurement, power consumption.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1189391 Low Cost Technique for Measuring Luminance in Biological Systems
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In this work, the relationship between the melanin content in a tissue and subsequent absorption of light through that tissue was determined using a digital camera. This technique proved to be simple, cost effective, efficient and reliable. Tissue phantom samples were created using milk and soy sauce to simulate the optical properties of melanin content in human tissue. Increasing the concentration of soy sauce in the milk correlated to an increase in melanin content of an individual. Two methods were employed to measure the light transmitted through the sample. The first was direct measurement of the transmitted intensity using a conventional lux meter. The second method involved correctly calibrating an ordinary digital camera and using image analysis software to calculate the transmitted intensity through the phantom. The results from these methods were then graphically compared to the theoretical relationship between the intensity of transmitted light and the concentration of absorbers in the sample. Conclusions were then drawn about the effectiveness and efficiency of these low cost methods.Keywords: Tissue phantoms, scattering coefficient, albedo, low-cost method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1301390 Study of Natural Convection Heat Transfer of Plate-Fin Heat Sink in a Closed Enclosure
Authors: Han-Taw Chen, Tzu-Hsiang Lin, Chung-Hou Lai
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The present study applies the inverse method and three-dimensional CFD commercial software in conjunction with the experimental temperature data to investigate the heat transfer and fluid flow characteristics of the plate-fin heat sink in a rectangular closed enclosure. The inverse method with the finite difference method and the experimental temperature data is applied to determine the approximate heat transfer coefficient. Later, based on the obtained results, the zero-equation turbulence model is used to obtain the heat transfer and fluid flow characteristics between two fins. T0 validate the accuracy of the results obtained, the comparison of the heat transfer coefficient is made. The obtained temperature at selected measurement locations of the fin is also compared with experimental data. The effect of the height of the rectangular enclosure on the obtained results is discussed.Keywords: Inverse method, FLUENT, Plate-fin heat sink, Heat transfer characteristics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2251389 A Fuzzy Swarm Optimized Approach for Piece Selection in Bit Torrent Like Peer to Peer Network
Authors: M. Padmavathi, R. M. Suresh
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Every machine plays roles of client and server simultaneously in a peer-to-peer (P2P) network. Though a P2P network has many advantages over traditional client-server models regarding efficiency and fault-tolerance, it also faces additional security threats. Users/IT administrators should be aware of risks from malicious code propagation, downloaded content legality, and P2P software’s vulnerabilities. Security and preventative measures are a must to protect networks from potential sensitive information leakage and security breaches. Bit Torrent is a popular and scalable P2P file distribution mechanism which successfully distributes large files quickly and efficiently without problems for origin server. Bit Torrent achieved excellent upload utilization according to measurement studies, but it also raised many questions as regards utilization in settings, than those measuring, fairness, and Bit Torrent’s mechanisms choice. This work proposed a block selection technique using Fuzzy ACO with optimal rules selected using ACO.
Keywords: Ant Colony Optimization (ACO), Bit Torrent, Download time, Peer-to-Peer (P2P) network, Performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2587388 Topological Sensitivity Analysis for Reconstruction of the Inverse Source Problem from Boundary Measurement
Authors: Maatoug Hassine, Mourad Hrizi
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In this paper, we consider a geometric inverse source problem for the heat equation with Dirichlet and Neumann boundary data. We will reconstruct the exact form of the unknown source term from additional boundary conditions. Our motivation is to detect the location, the size and the shape of source support. We present a one-shot algorithm based on the Kohn-Vogelius formulation and the topological gradient method. The geometric inverse source problem is formulated as a topology optimization one. A topological sensitivity analysis is derived from a source function. Then, we present a non-iterative numerical method for the geometric reconstruction of the source term with unknown support using a level curve of the topological gradient. Finally, we give several examples to show the viability of our presented method.Keywords: Geometric inverse source problem, heat equation, topological sensitivity, topological optimization, Kohn-Vogelius formulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1119387 Fully Printed Strain Gauges: A Comparison of Aerosoljet-Printing and Micropipette-Dispensing
Authors: Benjamin Panreck, Manfred Hild
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Strain sensors based on a change in resistance are well established for the measurement of forces, stresses, or material fatigue. Within the scope of this paper, fully additive manufactured strain sensors were produced using an ink of silver nanoparticles. Their behavior was evaluated by periodic tensile tests. Printed strain sensors exhibit two advantages: Their measuring grid is adaptable to the use case and they do not need a carrier-foil, as the measuring structure can be printed directly onto a thin sprayed varnish layer on the aluminum specimen. In order to compare quality characteristics, the sensors have been manufactured using two different technologies, namely aerosoljet-printing and micropipette-dispensing. Both processes produce structures which exhibit continuous features (in contrast to what can be achieved with droplets during inkjet printing). Briefly summarized the results show that aerosoljet-printing is the preferable technology for specimen with non-planar surfaces whereas both technologies are suitable for flat specimen.Keywords: Aerosoljet-printing, micropipette-dispensing, printed electronics, printed sensors, strain gauge.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1009386 Nuclear Data Evaluation for 217Po
Authors: Sherif S. Nafee, Amir K. Al-Ramady, Salem S. Shaheen
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Evaluated nuclear decay data for the 217Po nuclide is presented in the present work. These data include recommended values for the half-life T1/2, α-, β-- and γ-ray emission energies and probabilities. Decay data from 221Rn α and 217Bi β—decays are presented. Q(α) has been updated based on the recent published work of the Atomic Mass Evaluation AME2012. In addition, the logft values were calculated using the Logft program from the ENSDF evaluation package. Moreover, the total internal conversion electrons and the K-shell to L-shell and L-shell to M-shell and to N-shell conversion electrons ratios K/L, L/M and L/N have been calculated using Bricc program. Meanwhile, recommendation values or the multi-polarities have been assigned based on recently measurement yield a better intensity balance at the 254 keV and 264 keV gamma transitions.
Keywords: Atomic Mass Evaluation, Nuclear Data Evaluation, Total Electron Conversion Electrons.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2255385 Application of Neural Networks to Predict Changing the Diameters of Bubbles in Pool Boiling Distilled Water
Authors: V. Nikkhah Rashidabad, M. Manteghian, M. Masoumi, S. Mousavian, D. Ashouri
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In this research, the capability of neural networks in modeling and learning complicated and nonlinear relations has been used to develop a model for the prediction of changes in the diameter of bubbles in pool boiling distilled water. The input parameters used in the development of this network include element temperature, heat flux, and retention time of bubbles. The test data obtained from the experiment of the pool boiling of distilled water, and the measurement of the bubbles form on the cylindrical element. The model was developed based on training algorithm, which is typologically of back-propagation type. Considering the correlation coefficient obtained from this model is 0.9633. This shows that this model can be trusted for the simulation and modeling of the size of bubble and thermal transfer of boiling.
Keywords: Bubble Diameter, Heat Flux, Neural Network, Training Algorithm.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1456384 A Polyimide Based Split-Ring Neural Interface Electrode for Neural Signal Recording
Authors: Ning Xue, Srinivas Merugu, Ignacio Delgado Martinez, Tao Sun, John Tsang, Shih-Cheng Yen
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We have developed a polyimide based neural interface electrode to record nerve signals from the sciatic nerve of a rat. The neural interface electrode has a split-ring shape, with four protruding gold electrodes for recording, and two reference gold electrodes around the split-ring. The split-ring electrode can be opened up to encircle the sciatic nerve. The four electrodes can be bent to sit on top of the nerve and hold the device in position, while the split-ring frame remains flat. In comparison, while traditional cuff electrodes can only fit certain sizes of the nerve, the developed device can fit a variety of rat sciatic nerve dimensions from 0.6 mm to 1.0 mm, and adapt to the chronic changes in the nerve as the electrode tips are bendable. The electrochemical impedance spectroscopy measurement was conducted. The gold electrode impedance is on the order of 10 kΩ, showing excellent charge injection capacity to record neural signals.
Keywords: Impedance, neural interface, split-ring electrode.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2598383 Investigating Performance of Numerical Distance Relay with Higher Order Antialiasing Filter
Authors: Venkatesh C., K. Shanti Swarup
Abstract:
This paper investigates the impact on operating time delay and relay maloperation when 1st,2nd and 3rd order analog antialiasing filters are used in numerical distance protection. RC filter with cut-off frequency 90 Hz is used. Simulations are carried out for different SIR (Source to line Impedance Ratio), load, fault type and fault conditions using SIMULINK, where the voltage and current signals are fed online to the developed numerical distance relay model. Matlab is used for plotting the impedance trajectory. Investigation results shows that, about 75 % of the simulated cases, numerical distance relay operating time is not increased even-though there is a time delay when higher order filters are used. Relay maloperation (selectivity) also reduces (increases) when higher order filters are used in numerical distance protection.
Keywords: Antialiasing, capacitive voltage transformers, delay estimation, discrete Fourier transform (DFT), distance measurement, low-pass filters, source to line impedance ratio (SIR), protective relaying.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2797382 Mathematical Modeling of SISO based Timoshenko Structures – A Case Study
Authors: T.C. Manjunath, Student Member, B. Bandyopadhyay
Abstract:
This paper features the mathematical modeling of a single input single output based Timoshenko smart beam. Further, this mathematical model is used to design a multirate output feedback based discrete sliding mode controller using Bartoszewicz law to suppress the flexural vibrations. The first 2 dominant vibratory modes is retained. Here, an application of the discrete sliding mode control in smart systems is presented. The algorithm uses a fast output sampling based sliding mode control strategy that would avoid the use of switching in the control input and hence avoids chattering. This method does not need the measurement of the system states for feedback as it makes use of only the output samples for designing the controller. Thus, this methodology is more practical and easy to implement.
Keywords: Smart structure, Timoshenko beam theory, Discretesliding mode control, Bartoszewicz law, Finite Element Method, State space model, Vibration control, Mathematical model, SISO.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2392