Search results for: hole diameter error.
1148 Evaluation of the Effect of Rotor Solidity on the Performance of a H-Darrieus Turbine Adopting a Blade Element-Momentum Algorithm
Authors: G. Bedon, M. Raciti Castelli, E. Benini
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The present study aims to evaluating the effect of rotor solidity - in terms of chord length for a given rotor diameter - on the performances of a small vertical axis Darrieus wind turbine. The proposed work focuses on both power production and rotor power coefficient, considering also the structural constraints deriving from the centrifugal forces due to rotor angular velocity. Also the smoothness of the resulting power curves have been investigated, in order to evaluate the controllability of the corresponding rotor architectures.Keywords: Vertical axis wind turbine, Darrieus, solidity, Blade Element-Momentum
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 59501147 A Comparison of Signal Processing Techniques for the Extraction of Breathing Rate from the Photoplethysmogram
Authors: Susannah G. Fleming Lionel Tarassenko
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The photoplethysmogram (PPG) is the pulsatile waveform produced by the pulse oximeter, which is widely used for monitoring arterial oxygen saturation in patients. Various methods for extracting the breathing rate from the PPG waveform have been compared using a consistent data set, and a novel technique using autoregressive modelling is presented. This novel technique is shown to outperform the existing techniques, with a mean error in breathing rate of 0.04 breaths per minute.Keywords: Autoregressive modelling, breathing rate, photoplethysmogram, pulse oximetry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32971146 Effect of Landfill Leachate on Engineering Properties of Test Soil
Authors: S. A. Nta, M. J. Ayotamuno, I. J. Udom
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The work presents result of laboratory analysis of the effects of landfill leachate on engineering properties of test soil. The soil used for the present study was a sandy loam soil and acidic in nature. It was collected at a depth of 0.9 m. The landfill leachate used was collected from a hole dug some meters away from dumped solid waste and analyzed to identify the pollutants and its effect on engineering properties of the test soil. The test soil applied with landfill leachate was collected at 0.25 and 0.50 m radial distances at a depth of 0.15, 0.30, 0.45 and 0.60 m from the point of application of leachate after 50 days were the application of the leachate end and 80 days from the start of the experiment for laboratory analysis. Engineering properties such as particle size distribution, specific gravity, optimum moisture content, maximum dry density, unconfined compressive strength, liquid limit, plastic limit and shrinkage limit were considered. The concentration of various chemicals at 0.25 and 0.50 radial distances and 0.15, 0.30, 0.45 and 0.6 m depth from the point of application of leachate were different. This study founds the effect of landfill leachate on the engineering properties of soil. It can be concluded that, the type of soil, chemical composition of the leachate, infiltration rate, aquifers, ground water table etc., will have a major role on the area of influence zone of the pollutants in a landfill.
Keywords: Engineering properties of test soil, landfill leachate, Municipal solid waste.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6341145 Texture Observation of Bending by XRD and EBSD Method
Authors: Takashi Sakai, Yuri Shimomura
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The crystal orientation is a factor that affects the microscopic material properties. Crystal orientation determines the anisotropy of the polycrystalline material. And it is closely related to the mechanical properties of the material. In this paper, for pure copper polycrystalline material, two different methods; X-Ray Diffraction (XRD) and Electron Backscatter Diffraction (EBSD); and the crystal orientation were analyzed. In the latter method, it is possible that the X-ray beam diameter is thicker as compared to the former, to measure the crystal orientation macroscopically relatively. By measurement of the above, we investigated the change in crystal orientation and internal tissues of pure copper.
Keywords: Bending, electron backscatter diffraction, X-ray diffraction, microstructure, IPF map, orientation distribution function.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17441144 Measures and Influence of a Baw Filter on Digital Radio-Communications Signals
Authors: A. Diet, M. Villegas, G. Baudoin
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This work concerns the measurements of a Bulk Acoustic Waves (BAW) emission filter S parameters and compare with prototypes simulated types. Thanks to HP-ADS, a co-simulation of filters- characteristics in a digital radio-communication chain is performed. Four cases of modulation schemes are studied in order to illustrate the impact of the spectral occupation of the modulated signal. Results of simulations and co-simulation are given in terms of Error Vector Measurements to be useful for a general sensibility analysis of 4th/3rd Generation (G.) emitters (wideband QAM and OFDM signals)Keywords: RF architectures, BAW filters.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27661143 Estimation of Shock Velocity and Pressure of Detonations and Finding Their Flow Parameters
Authors: Mahmoud Zarrini, R. N. Pralhad
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In this paper, mathematical modeling of detonation in the ground is studied. Estimation of flow parameters such as velocity, maximum velocity, acceleration, maximum acceleration, shock pressure as a result of an explosion in the ground have been computed in an appropriate dynamic model approach. The variation of these parameters with the diameter of detonation place (L), density of earth or stone (¤ü), time decay of detonation (T), peak pressure (Pm), and time (t) have been analyzed. The model has been developed from the concept of underwater explosions [Refs. [1]-[3]] with appropriate changes to the present model requirements.
Keywords: Shock velocity, detonation, shock acceleration, shock pressure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12871142 Test Method Development for Evaluation of Process and Design Effect on Reinforced Tube
Authors: Cathal Merz, Gareth O’Donnell
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Coil reinforced thin-walled (CRTW) tubes are used in medicine to treat problems affecting blood vessels within the body through minimally invasive procedures. The CRTW tube considered in this research makes up part of such a device and is inserted into the patient via their femoral or brachial arteries and manually navigated to the site in need of treatment. This procedure replaces the requirement to perform open surgery but is limited by reduction of blood vessel lumen diameter and increase in tortuosity of blood vessels deep in the brain. In order to maximize the capability of these procedures, CRTW tube devices are being manufactured with decreasing wall thicknesses in order to deliver treatment deeper into the body and to allow passage of other devices through its inner diameter. This introduces significant stresses to the device materials which have resulted in an observed increase in the breaking of the proximal segment of the device into two separate pieces after it has failed by buckling. As there is currently no international standard for measuring the mechanical properties of these CRTW tube devices, it is difficult to accurately analyze this problem. The aim of the current work is to address this discrepancy in the biomedical device industry by developing a measurement system that can be used to quantify the effect of process and design changes on CRTW tube performance, aiding in the development of better performing, next generation devices. Using materials testing frames, micro-computed tomography (micro-CT) imaging, experiment planning, analysis of variance (ANOVA), T-tests and regression analysis, test methods have been developed for assessing the impact of process and design changes on the device. The major findings of this study have been an insight into the suitability of buckle and three-point bend tests for the measurement of the effect of varying processing factors on the device’s performance, and guidelines for interpreting the output data from the test methods. The findings of this study are of significant interest with respect to verifying and validating key process and design changes associated with the device structure and material condition. Test method integrity evaluation is explored throughout.
Keywords: Buckling, coil reinforced thin-walled tubes, fracture, test method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6751141 Effective Charge Coupling in Low Dimensional Doped Quantum Antiferromagnets
Authors: Suraka Bhattacharjee, Ranjan Chaudhury
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The interaction between the charge degrees of freedom for itinerant antiferromagnets is investigated in terms of generalized charge stiffness constant corresponding to nearest neighbour t-J model and t1-t2-t3-J model. The low dimensional hole doped antiferromagnets are the well known systems that can be described by the t-J-like models. Accordingly, we have used these models to investigate the fermionic pairing possibilities and the coupling between the itinerant charge degrees of freedom. A detailed comparison between spin and charge couplings highlights that the charge and spin couplings show very similar behaviour in the over-doped region, whereas, they show completely different trends in the lower doping regimes. Moreover, a qualitative equivalence between generalized charge stiffness and effective Coulomb interaction is also established based on the comparisons with other theoretical and experimental results. Thus it is obvious that the enhanced possibility of fermionic pairing is inherent in the reduction of Coulomb repulsion with increase in doping concentration. However, the increased possibility can not give rise to pairing without the presence of any other pair producing mechanism outside the t-J model. Therefore, one can conclude that the t-J-like models themselves solely are not capable of producing conventional momentum-based superconducting pairing on their own.Keywords: Generalized charge stiffness constant, charge coupling, effective Coulomb interaction, t-J-like models, momentum-space pairing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6041140 Kinetics of Palm Oil Cracking in Batch Reactor
Authors: Farouq Twaiq, Ishaq Al-Anbari, Mustafa Nasser
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The kinetics of palm oil catalytic cracking over aluminum containing mesoporous silica Al-MCM-41 (5% Al) was investigated in a batch autoclave reactor at the temperatures range of 573 – 673 K. The catalyst was prepared by using sol-gel technique and has been characterized by nitrogen adsorption and x-ray diffraction methods. Surface area of 1276 m2/g with average pore diameter of 2.54 nm and pore volume of 0.811 cm3/g was obtained. The experimental catalytic cracking runs were conducted using 50 g of oil and 1 g of catalyst. The reaction pressure was recorded at different time intervals and the data were analyzed using Levenberg- Marquardt (LM) algorithm using polymath software. The results show that the reaction order was found to be -1.5 and activation energy of 3200 J/gmol.Keywords: Batch Reactor, Catalytic Cracking, Kinetics, Palm Oil.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29851139 Watermark-based Counter for Restricting Digital Audio Consumption
Authors: Mikko Löytynoja, Nedeljko Cvejic, Tapio Seppänen
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In this paper we introduce three watermarking methods that can be used to count the number of times that a user has played some content. The proposed methods are tested with audio content in our experimental system using the most common signal processing attacks. The test results show that the watermarking methods used enable the watermark to be extracted under the most common attacks with a low bit error rate.
Keywords: Digital rights management, restricted usage, content protection, spread spectrum, audio watermarking.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14571138 Effect of Relative Permeability on Well Testing Behavior of Naturally Fractured Lean Gas Condensate Reservoirs
Authors: G.H. Montazeri, Z. Dastkhan, H. Aliabadi
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Gas condensate Reservoirs show complicated thermodynamic behavior when their pressure reduces to under dew point pressure. Condensate blockage around the producing well cause significant reduction of production rate as well bottom-hole pressure drops below saturation pressure. The main objective of this work was to examine the well test analysis of naturally fractured lean gas condensate reservoir and investigate the effect of condensate formed around the well-bore on behavior of single phase pseudo pressure and its derivative curves. In this work a naturally fractured lean gas condensate reservoir is simulated with compositional simulator. Different sensitivity analysis done on Corry parameters and result of simulator is feed to analytical well testing software. For consideration of these phenomena eighteen compositional models with Capillary number effect are constructed. Matrix relative permeability obeys Corry relative permeability and relative permeability in fracture is linear. Well testing behavior of these models are studied and interpreted. Results show different sensitivity analysis on relative permeability of matrix does not have strong effect on well testing behavior even most part of the matrix around the well is occupied with condensate.
Keywords: Lean gas, fractured condensate reservoir, capillary number, well testing analysis, relative permeability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29551137 Dual Construction of Stern-based Signature Scheme
Authors: Pierre-Louis Cayrel, Sidi Mohamed El Yousfi Alaoui
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In this paper, we propose a dual version of the first threshold ring signature scheme based on error-correcting code proposed by Aguilar et. al in [1]. Our scheme uses an improvement of Véron zero-knowledge identification scheme, which provide smaller public and private key sizes and better computation complexity than the Stern one. This scheme is secure in the random oracle model.Keywords: Stern algorithm, Véron algorithm, threshold ring signature, post-quantum cryptography.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17911136 Wasting Human and Computer Resources
Authors: Mária Csernoch, Piroska Biró
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The legends about “user-friendly” and “easy-to-use” birotical tools (computer-related office tools) have been spreading and misleading end-users. This approach has led us to the extremely high number of incorrect documents, causing serious financial losses in the creating, modifying, and retrieving processes. Our research proved that there are at least two sources of this underachievement: (1) The lack of the definition of the correctly edited, formatted documents. Consequently, end-users do not know whether their methods and results are correct or not. They are not aware of their ignorance. They are so ignorant that their ignorance does not allow them to realize their lack of knowledge. (2) The end-users’ problem solving methods. We have found that in non-traditional programming environments end-users apply, almost exclusively, surface approach metacognitive methods to carry out their computer related activities, which are proved less effective than deep approach methods. Based on these findings we have developed deep approach methods which are based on and adapted from traditional programming languages. In this study, we focus on the most popular type of birotical documents, the text based documents. We have provided the definition of the correctly edited text, and based on this definition, adapted the debugging method known in programming. According to the method, before the realization of text editing, a thorough debugging of already existing texts and the categorization of errors are carried out. With this method in advance to real text editing users learn the requirements of text based documents and also of the correctly formatted text. The method has been proved much more effective than the previously applied surface approach methods. The advantages of the method are that the real text handling requires much less human and computer sources than clicking aimlessly in the GUI (Graphical User Interface), and the data retrieval is much more effective than from error-prone documents.
Keywords: Deep approach metacognitive methods, error-prone birotical documents, financial losses, human and computer resources.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19051135 Variable Step-Size APA with Decorrelation of AR Input Process
Authors: Jae Wook Shin, Ju-man Song, Hyun-Taek Choi, Poo Gyeon Park
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This paper introduces a new variable step-size APA with decorrelation of AR input process is based on the MSD analysis. To achieve a fast convergence rate and a small steady-state estimation error, he proposed algorithm uses variable step size that is determined by minimising the MSD. In addition, experimental results show that the proposed algorithm is achieved better performance than the other algorithms.
Keywords: adaptive filter, affine projection algorithm, variable step size.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18861134 A Numerical Study of a Droplet Impinging on a Liquid Surface
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The Navier–Stokes equations for unsteady, incompressible, viscous fluids in the axisymmetric coordinate system are solved using a control volume method. The volume-of-fluid (VOF) technique is used to track the free-surface of the liquid. Model predictions are in good agreement with experimental measurements. It is found that the dynamic processes after impact are sensitive to the initial droplet velocity and the liquid pool depth. The time evolution of the crown height and diameter are obtained by numerical simulation. The critical We number for splashing (Wecr) is studied for Oh (Ohnesorge) numbers in the range of 0.01~0.1; the results compares well with those of the experiments.
Keywords: Droplet impingement, free surface flows, liquid crown, numerical simulation, thin liquid film.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19731133 BER Performance of UWB Modulations through S-V Channel Model
Authors: Risanuri Hidayat
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BER analysis of Impulse Radio Ultra Wideband (IRUWB) pulse modulations over S-V channel model is proposed in this paper. The UWB pulse is Gaussian monocycle pulse modulated using Pulse Amplitude Modulation (PAM) and Pulse Position Modulation (PPM). The channel model is generated from a modified S-V model. Bit-error rate (BER) is measured over several of bit rates. The result shows that all modulation are appropriate for both LOS and NLOS channel, but PAM gives better performance in bit rates and SNR. Moreover, as standard of speed has been given for UWB, the communication is appropriate with high bit rates in LOS channel.
Keywords: IR-UWB, S-V Channel Model, LOS NLOS, PAM, PPM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23341132 Impact of Process Variations on the Vertical Silicon Nanowire Tunneling FET (TFET)
Authors: Z. X. Chen, T. S. Phua, X. P. Wang, G. -Q. Lo, D. -L. Kwong
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This paper presents device simulations on the vertical silicon nanowire tunneling FET (VSiNW TFET). Simulations show that a narrow nanowire and thin gate oxide is required for good performance, which is expected even for conventional MOSFETs. The gate length also needs to be more than the nanowire diameter to prevent short channel effects. An effect more unique to TFET is the need for abrupt source to channel junction, which is shown to improve the performance. The ambipolar effect suppression by reducing drain doping concentration is also explored and shown to have little or no effect on performance.
Keywords: Device simulation, MEDICI, tunneling FET (TFET), vertical silicon nanowire.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26261131 Variable Regularization Parameter Normalized Least Mean Square Adaptive Filter
Authors: Young-Seok Choi
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We present a normalized LMS (NLMS) algorithm with robust regularization. Unlike conventional NLMS with the fixed regularization parameter, the proposed approach dynamically updates the regularization parameter. By exploiting a gradient descent direction, we derive a computationally efficient and robust update scheme for the regularization parameter. In simulation, we demonstrate the proposed algorithm outperforms conventional NLMS algorithms in terms of convergence rate and misadjustment error.Keywords: Regularization, normalized LMS, system identification, robustness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18701130 Flow around Two Cam Shaped Cylinders in Tandem Arrangement
Authors: Arash Mir Abdolah Lavasani, Hamidreza Bayat
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In this paper flow around two cam shaped cylinders had been studied numerically. The equivalent diameter of cylinders is 27.6 mm. The space between center to center of two cam shaped cylinders is define as longitudinal pitch ratio and it varies in range of
2
Keywords: Cam shaped, tandem cylinders, numerical, drag coefficient.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16301129 Used Frying Oil for Biodiesel Production Over Kaolinite as Catalyst
Authors: Jorge Ramírez-Ortiz, Jorge Medina-Valtierra, Merced Martínez Rosales
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Biodiesel production with used frying by transesterification reaction with methanol, using a commercial kaolinite thermally-activated solid acid catalyst was investigated. The surface area, the average pore diameter and pore volume of the kaolinite catalyst were 10 m2/g, 13.0 nm and 30 mm3/g, respectively. The optimal conditions for the transesterification reaction were determined to be oil/methanol, in a molar ratio 1:31, temperature 160 ºC and catalyst concentration of 3% (w/w). The yield of fatty acids methyl esters (FAME) was 92.4% after 2 h of reaction. This method of preparation of biodiesel can be a positive alternative for utilizing used frying corn oil for feedstock of biodiesel combined with the inexpensive catalyst.Keywords: Biodiesel, frying corn oil, kaolinite, transesterification
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20841128 Union is Strength in Lossy Image Compression
Authors: Mario Mastriani
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In this work, we present a comparison between different techniques of image compression. First, the image is divided in blocks which are organized according to a certain scan. Later, several compression techniques are applied, combined or alone. Such techniques are: wavelets (Haar's basis), Karhunen-Loève Transform, etc. Simulations show that the combined versions are the best, with minor Mean Squared Error (MSE), and higher Peak Signal to Noise Ratio (PSNR) and better image quality, even in the presence of noise.Keywords: Haar's basis, Image compression, Karhunen-LoèveTransform, Morton's scan, row-rafter scan.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17381127 H2 Permeation Properties of a Catalytic Membrane Reactor in Methane Steam Reforming Reaction
Authors: M. Amanipour, J. Towfighi, E. Ganji Babakhani, M. Heidari
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Cylindrical alumina microfiltration membrane (GMITM Corporation, inside diameter=9 mm, outside diameter=13 mm, length= 50 mm) with an average pore size of 0.5 micrometer and porosity of about 0.35 was used as the support for membrane reactor. This support was soaked in boehmite sols, and the mean particle size was adjusted in the range of 50 to 500 nm by carefully controlling hydrolysis time, and calcined at 650 °C for two hours. This process was repeated with different boehmite solutions in order to achieve an intermediate layer with an average pore size of about 50 nm. The resulting substrate was then coated with a thin and dense layer of silica by counter current chemical vapour deposition (CVD) method. A boehmite sol with 10 wt.% of nickel which was prepared by a standard procedure was used to make the catalytic layer. BET, SEM, and XRD analysis were used to characterize this layer. The catalytic membrane reactor was placed in an experimental setup to evaluate the permeation and hydrogen separation performance for a steam reforming reaction. The setup consisted of a tubular module in which the membrane was fixed, and the reforming reaction occurred at the inner side of the membrane. Methane stream, diluted with nitrogen, and deionized water with a steam to carbon (S/C) ratio of 3.0 entered the reactor after the reactor was heated up to 500 °C with a specified rate of 2 °C/ min and the catalytic layer was reduced at presence of hydrogen for 2.5 hours. Nitrogen flow was used as sweep gas through the outer side of the reactor. Any liquid produced was trapped and separated at reactor exit by a cold trap, and the produced gases were analyzed by an on-line gas chromatograph (Agilent 7890A) to measure total CH4 conversion and H2 permeation. BET analysis indicated uniform size distribution for catalyst with average pore size of 280 nm and average surface area of 275 m2.g-1. Single-component permeation tests were carried out for hydrogen, methane, and carbon dioxide at temperature range of 500-800 °C, and the results showed almost the same permeance and hydrogen selectivity values for hydrogen as the composite membrane without catalytic layer. Performance of the catalytic membrane was evaluated by applying membranes as a membrane reactor for methane steam reforming reaction at gas hourly space velocity (GHSV) of 10,000 h−1 and 2 bar. CH4 conversion increased from 50% to 85% with increasing reaction temperature from 600 °C to 750 °C, which is sufficiently above equilibrium curve at reaction conditions, but slightly lower than membrane reactor with packed nickel catalytic bed because of its higher surface area compared to the catalytic layer.Keywords: Catalytic membrane, hydrogen, methane steam reforming, permeance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8811126 Characterization of Silica Nanoparticles in Interaction with Escherichia coli Bacteria
Authors: Ibtissem Gammoudi, Ndeye Rokhaya Faye, Fabien Moroté, Daniel Moynet, Christine Grauby-Heywang, Touria Cohen-Bouhacina
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The objective of the present investigation was to evaluate the morphology of Escherchia coli bacteria in interaction with SiO2 nanoparticles. This study was made by atomic force microscopy and quartz crystal microbalance using SiO2 nanoparticles with 10nm, 50nm and 100nm diameter and bacteria immobilized on polyelectrolyte multilayer films obtained by spin coating or by “layer by layer” (LbL) method.
Keywords: Atomic Force Microscopy, Escherichia coli, Quartz Crystal Microbalance, polyelectrolyte, silica nanoparticle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26731125 Polyurethane Nanofibers Obtained By Electrospinning Process
Authors: H. Karakaş, A.S. Saraç, T. Polat, E.G. Budak, S. Bayram, N. Dağ, S. Jahangiri
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Electrospinning is a broadly used technology to obtain polymeric nanofibers ranging from several micrometers down to several hundred nanometers for a wide range of applications. It offers unique capabilities to produce nanofibers with controllable porous structure. With smaller pores and higher surface area than regular fibers, electrospun fibers have been successfully applied in various fields, such as, nanocatalysis, tissue engineering scaffolds, protective clothing, filtration, biomedical, pharmaceutical, optical electronics, healthcare, biotechnology, defense and security, and environmental engineering. In this study, polyurethane nanofibers were obtained under different electrospinning parameters. Fiber morphology and diameter distribution were investigated in order to understand them as a function of process parameters.Keywords: Electrospinning, polyurethane, nanofibers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 47831124 Bootstrap and MLS Methods-based Individual Bioequivalence Assessment
Authors: Kongsheng Zhang, Li Ge
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It is a one-sided hypothesis testing process for assessing bioequivalence. Bootstrap and modified large-sample(MLS) methods are considered to study individual bioequivalence(IBE), type I error and power of hypothesis tests are simulated and compared with FDA(2001). The results show that modified large-sample method is equivalent to the method of FDA(2001) .
Keywords: Individual bioequivalence, bootstrap, Bayesian bootstrap, modified large-sample.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15691123 Harvesting of Kinetic Energy of the Raindrops
Authors: K. C. R. Perera, B. G. Sampath, V. P. C. Dassanayake, B. M. Hapuwatte.
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This paper presents a methodology to harvest the kinetic energy of the raindrops using piezoelectric devices. In the study 1m×1m PVDF (Polyvinylidene fluoride) piezoelectric membrane, which is fixed by the four edges, is considered for the numerical simulation on deformation of the membrane due to the impact of the raindrops. Then according to the drop size of the rain, the simulation is performed classifying the rainfall types into three categories as light stratiform rain, moderate stratiform rain and heavy thundershower. The impact force of the raindrop is dependent on the terminal velocity of the raindrop, which is a function of raindrop diameter. The results were then analyzed to calculate the harvestable energy from the deformation of the piezoelectric membrane.
Keywords: Raindrop, piezoelectricity, deformation, terminal velocity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 65831122 Modeling and Validation of Microspheres Generation in the Modified T-Junction Device
Authors: Lei Lei, Hongbo Zhang, Donald J. Bergstrom, Bing Zhang, K. Y. Song, W. J. Zhang
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This paper presents a model for a modified T-junction device for microspheres generation. The numerical model is developed using a commercial software package: COMSOL Multiphysics. In order to test the accuracy of the numerical model, multiple variables, such as the flow rate of cross-flow, fluid properties, structure, and geometry of the microdevice are applied. The results from the model are compared with the experimental results in the diameter of the microsphere generated. The comparison shows a good agreement. Therefore the model is useful in further optimization of the device and feedback control of microsphere generation if any.
Keywords: CFD modeling, validation, microsphere generation, modified T-junction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25511121 Fusion Filters Weighted by Scalars and Matrices for Linear Systems
Authors: Seok Hyoung Lee, Vladimir Shin
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An optimal mean-square fusion formulas with scalar and matrix weights are presented. The relationship between them is established. The fusion formulas are compared on the continuous-time filtering problem. The basic differential equation for cross-covariance of the local errors being the key quantity for distributed fusion is derived. It is shown that the fusion filters are effective for multi-sensor systems containing different types of sensors. An example demonstrating the reasonable good accuracy of the proposed filters is given.Keywords: Kalman filtering, fusion formula, multi-sensor, mean-square error.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13831120 Physical Parameter Based Compact Expression for Propagation Constant of SWCNT Interconnects
Authors: Kollarama Subramanyam, Nisha Kuruvilla, J. P. Raina
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Novel compact expressions for propagation constant (γ) of SWCNT and bundled SWCNTs interconnect, in terms of physical parameters such as length, operating frequency and diameter of CNTs is proposed in this work. These simplified expressions enable physical insight and accurate estimation of signal attenuation level and its phase change at any length for a particular frequency. The proposed expressions are validated against SPICE simulated results of lumped as well as distributed equivalent electrical RLC nets of CNT interconnect. These expressions also help us to evaluate the cut off frequencies of SWCNTs for different interconnect lengths.
Keywords: Attenuation constant, Bundled SWCNT, CNT interconnects, Propagation Constant.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16651119 The Effect of Angle of Attack on Pressure Drag from a Cam Shaped Tube
Authors: Arash Mir Abdolah Lavasani
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The pressure drag from a cam shaped tube in cross flows have been investigated experimentally using pressure distribution measurement. The range of angle of attack and Reynolds number based on an equivalent circular tube are within 0≤α≤360° and 2×104< Reeq < 3.4 ×104, respectively. It is found that the pressure drag coefficient is at its highest at α=90° and 270° over the whole range of Reynolds number. Results show that the pressure drag coefficient of the cam shaped tube is lower than that of circular tube with the same surface area for more of the angles of attack. Furthermore, effects of the diameter ratio and finite length of the cam shaped tube upon the pressure drag coefficient are discussed.
Keywords: Pressure Drag, Cam Shaped, Experimental.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2370