Search results for: autocorrelation length.
508 Flow inside Micro-Channel Bounded by Superhydrophobic Surface with Eccentric Micro-Grooves
Authors: Yu Chen, Weiwei Ren, Xiaojing Mu, Feng Zhang, Yi Xu
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The superhydrophobic surface is widely used to reduce friction for the flow inside micro-channel and can be used to control/manipulate fluid, cells and even proteins in lab-on-chip. Fabricating micro grooves on hydrophobic surfaces is a common method to obtain such superhydrophobic surface. This study utilized the numerical method to investigate the effect of eccentric micro-grooves on the friction of flow inside micro-channel. A detailed parametric study was conducted to reveal how the eccentricity of micro-grooves affects the micro-channel flow under different grooves sizes, channel heights, Reynolds number. The results showed that the superhydrophobic surface with eccentric micro-grooves induces less friction than the counter part with aligning micro-grooves, which means requiring less power for pumps.Keywords: Superhydrophobic, transverse grooves, heat transfer, slip length, microfluidics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1030507 Effect of Cladding and Secondary Members on the Elastic Stability of Main Columns
Authors: Mohamed Massoud El Sadaawy, Ehab Hasan Ahmed Hasan Ali
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The corrugated steel cladding used to cover most of steel buildings is considered as non-structural element. This research will reflect the effect of cladding as a shear diaphragm in increasing the normal elastic capacity of columns. This study is important because of the lack of information of the behavior of cladding and secondary members in various codes. Mathematical models for six different cases are carried by software. The results extracted from the program have been plotted showing the effects of different variables on the ultimate load of column. The variables considered in our research are the spacing between columns and the thickness of the corrugated sheet representing the sheet stiffness.Keywords: Stability of frames about minor axis, The effective length factor, Effect of secondary members on elastic buckling load column, The stiffness of sheeting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2788506 Thermal Buckling of Rectangular FGM Plate with Variation Thickness
Authors: Mostafa Raki, Mahdi Hamzehei
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Equilibrium and stability equations of a thin rectangular plate with length a, width b, and thickness h(x)=C1x+C2, made of functionally graded materials under thermal loads are derived based on the first order shear deformation theory. It is assumed that the material properties vary as a power form of thickness coordinate variable z. The derived equilibrium and buckling equations are then solved analytically for a plate with simply supported boundary conditions. One type of thermal loading, uniform temperature rise and gradient through the thickness are considered, and the buckling temperatures are derived. The influences of the plate aspect ratio, the relative thickness, the gradient index and the transverse shear on buckling temperature difference are all discussed.
Keywords: Stability of plate, thermal buckling, rectangularplate, functionally graded material, first order shear deformationtheory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2087505 Synchrotron X-Ray Based Investigation of As and Fe Bonding Environment in Collard Green Tissue Samples at Different Growth Stages
Authors: Sunil Dehipawala, Aregama Sirisumana, P. Schneider, G. Tremberger Jr, D. Lieberman, Todd Holden T. Cheung
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The arsenic and iron environments in different growth stages have been studied with EXAFS and XANES using Brookhaven Synchrotron Light Source. Collard Greens plants were grown and tissue samples were harvested. The project studied the EXAFS and XANES of tissue samples using As and Fe K-edges. The Fe absorption and the Fourier transform bond length information were used as a control comparison. The Fourier transform of the XAFS data revealed the coexistence of As (III) and As (V) in the As bonding environment inside the studied plant tissue samples, although the soil only had As (III). The data suggests that Collard Greens has a novel pathway to handle arsenic absorption in soil.Keywords: EXAFS, Fourier Transform, metalloproteins, XANES.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1925504 Stochastic Estimation of Cavity Flowfield
Authors: Yin Yin Pey, Leok Poh Chua, Wei Long Siauw
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Linear stochastic estimation and quadratic stochastic estimation techniques were applied to estimate the entire velocity flow-field of an open cavity with a length to depth ratio of 2. The estimations were done through the use of instantaneous velocity magnitude as estimators. These measurements were obtained by Particle Image Velocimetry. The predicted flow was compared against the original flow-field in terms of the Reynolds stresses and turbulent kinetic energy. Quadratic stochastic estimation proved to be more superior than linear stochastic estimation in resolving the shear layer flow. When the velocity fluctuations were scaled up in the quadratic estimate, both the time-averaged quantities and the instantaneous cavity flow can be predicted to a rather accurate extent.Keywords: Open cavity, Particle Image Velocimetry, Stochastic estimation, Turbulent kinetic energy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1699503 Effect of Waste Bottle Chips on Strength Parameters of Silty Soil
Authors: Seyed Abolhasan Naeini, Hamidreza Rahmani
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Laboratory consolidated undrained triaxial (CU) tests were carried out to study the strength behavior of silty soil reinforced with randomly plastic waste bottle chips. Specimens mixed with plastic waste chips in triaxial compression tests with 0.25, 0.50, 0.75, 1.0, and 1.25% by dry weight of soil and tree different length including 4, 8, and 12 mm. In all of the samples, the width and thickness of plastic chips were kept constant. According to the results, the amount and size of plastic waste bottle chips played an important role in the increasing of the strength parameters of reinforced silt compared to the pure soil. Because of good results, the suggested method of soil improvement can be used in many engineering problems such as increasing the bearing capacity and settlement reduction in foundations.
Keywords: Soil improvement, waste bottle chips, reinforcement, silt, Triaxial test.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1951502 Elastic Failure of Web-Cracked Plate Girder
Authors: Sebastian B. Mendes
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The presence of a vertical fatigue crack in the web of a plate girder subjected to pure bending influences the bending moment capacity of the girder. The growth of the crack may lead to premature elastic failure due to flange local yielding, flange local buckling, or web local buckling. Approximate expressions for the bending moment capacities corresponding to these failure modes were formulated. Finite element analyses were then used to validate the expressions. The expressions were employed to assess the effects of crack length on the capacity. Neglecting brittle fracture, tension buckling, and ductile failure modes, it was found that typical girders are governed by the capacity associated with flange local yielding as influenced by the crack. Concluding, a possible use of the capacity expressions in girder design was demonstrated.Keywords: Fatigue crack, flange yielding, flange buckling, web buckling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2236501 A CTL Specification of Serializability for Transactions Accessing Uniform Data
Authors: Rafat Alshorman, Walter Hussak
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Existing work in temporal logic on representing the execution of infinitely many transactions, uses linear-time temporal logic (LTL) and only models two-step transactions. In this paper, we use the comparatively efficient branching-time computational tree logic CTL and extend the transaction model to a class of multistep transactions, by introducing distinguished propositional variables to represent the read and write steps of n multi-step transactions accessing m data items infinitely many times. We prove that the well known correspondence between acyclicity of conflict graphs and serializability for finite schedules, extends to infinite schedules. Furthermore, in the case of transactions accessing the same set of data items in (possibly) different orders, serializability corresponds to the absence of cycles of length two. This result is used to give an efficient encoding of the serializability condition into CTL.Keywords: computational tree logic, serializability, multi-step transactions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1167500 Alternative Convergence Analysis for a Kind of Singularly Perturbed Boundary Value Problems
Authors: Jiming Yang
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A kind of singularly perturbed boundary value problems is under consideration. In order to obtain its approximation, simple upwind difference discretization is applied. We use a moving mesh iterative algorithm based on equi-distributing of the arc-length function of the current computed piecewise linear solution. First, a maximum norm a posteriori error estimate on an arbitrary mesh is derived using a different method from the one carried out by Chen [Advances in Computational Mathematics, 24(1-4) (2006), 197-212.]. Then, basing on the properties of discrete Green-s function and the presented posteriori error estimate, we theoretically prove that the discrete solutions computed by the algorithm are first-order uniformly convergent with respect to the perturbation parameter ε.
Keywords: Convergence analysis, green's function, singularly perturbed, equi-distribution, moving mesh.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1686499 Detection and Pose Estimation of People in Images
Authors: Mousa Mojarrad, Amir Masoud Rahmani, Mehrab Mohebi
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Detection, feature extraction and pose estimation of people in images and video is made challenging by the variability of human appearance, the complexity of natural scenes and the high dimensionality of articulated body models and also the important field in Image, Signal and Vision Computing in recent years. In this paper, four types of people in 2D dimension image will be tested and proposed. The system will extract the size and the advantage of them (such as: tall fat, short fat, tall thin and short thin) from image. Fat and thin, according to their result from the human body that has been extract from image, will be obtained. Also the system extract every size of human body such as length, width and shown them in output.Keywords: Analysis of Image Processing, Canny Edge Detection, Human Body Recognition, Measurement, Pose Estimation, 2D Human Dimension.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2289498 Historical Landscape Affects Present Tree Density in Paddy Field
Authors: Ha T. Pham, Shuichi Miyagawa
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Ongoing landscape transformation is one of the major causes behind disappearance of traditional landscapes, and lead to species and resource loss. Tree in paddy fields in the northeast of Thailand is one of those traditional landscapes. Using three different historical time layers, we acknowledged the severe deforestation and rapid urbanization happened in the region. Despite the general thinking of decline in tree density as consequences, the heterogeneous trend of changes in total tree density in three studied landscapes denied the hypothesis that number of trees in paddy field depend on the length of land use practice. On the other hand, due to selection of planting new trees on levees, existence of trees in paddy field now relies on their values for human use. Besides, changes in land use and landscape structure had a significant impact on decision of which tree density level is considered as suitable for the landscape.
Keywords: Aerial photographs, land use change, traditional landscape, tree in paddy fields.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1856497 Analytic on Various Grounding Configurations in Uniform Layer Soil
Authors: Mohd Shahriman B. Mohd Yunus, Mohd Hanif B. Jamaludin, Norain Bt. Bahror
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The performance of an embedded grounding system is very important for the safe operation of electrical appliances and human beings. In principle, a safe grounding system has two objectives, which are to dissipate fault current without exceeding any operating and equipment limits and to ensure there is no risk of electric shock to humans in the vicinity of earthed facilities. The case studies in this paper present the calculating grounding resistance for multiple configurations of vertical and horizontally by using a simple and accurate formula. From the analytic calculated results, observed good/empirical relationship between the grounding resistance and length of the embedded grounding configurations. Moreover, the configurations of vertical and horizontal observed effectiveness of grounding resistance and good agreement on the reduction of grounding resistance values especially for vertical configuration.
Keywords: Grounding system, grounding resistance, soil resistivity, electrode geometry, configurations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 474496 Identifying Unknown Dynamic Forces Applied on Two Dimensional Frames
Authors: H. Katkhuda
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A time domain approach is used in this paper to identify unknown dynamic forces applied on two dimensional frames using the measured dynamic structural responses for a sub-structure in the two dimensional frame. In this paper a sub-structure finite element model with short length of measurement from only three or four accelerometers is required, and an iterative least-square algorithm is used to identify the unknown dynamic force applied on the structure. Validity of the method is demonstrated with numerical examples using noise-free and noise-contaminated structural responses. Both harmonic and impulsive forces are studied. The results show that the proposed approach can identify unknown dynamic forces within very limited iterations with high accuracy and shows its robustness even noise- polluted dynamic response measurements are utilized.
Keywords: Dynamic Force Identification, Dynamic Responses, Sub-structure and Time Domain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1525495 Application of the Experimental Planning Design to the Notched Precracked Tensile Fracture of Composite
Authors: N. Mahmoudi
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Composite materials have important assets compared to traditional materials. They bring many functional advantages: lightness, mechanical resistance and chemical, etc. In the present study we examine the effect of a circular central notch and a precrack on the tensile fracture of two woven composite materials. The tensile tests were applied to a standardized specimen, notched and a precarcked (orientation of the crack 0°, 45° and 90°). These tensile tests were elaborated according to an experimental planning design of the type 23.31 requiring 24 experiments with three repetitions. By the analysis of regression, we obtained a mathematical model describing the maximum load according to the influential parameters (hole diameter, precrack length, angle of a precrack orientation). The specimens precracked at 90° have a better behavior than those having a precrack at 45° and still better than those having of the precracks oriented at 0°. In addition the maximum load is inversely proportional to the notch size.
Keywords: Polymer matrix, Glasses, Fracture.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1853494 The Pack-Bed Sphere Liquid Porous Burner
Authors: B. Krittacom, P. Amatachaya, W. Srimuang, K. Inla
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The combustion of liquid fuel in the porous burner (PB) was experimented to investigate evaporation mechanism and combustion behavior. The diesel oil was used as fuel and the pebbles carefully chosen in the same size like the solid sphere homogeneously was adopted as the porous media. Two structures of the liquid porous burner, i.e. the PB without and with installation of porous emitter (PE), were performed. PE was installed by lower than PB with distance of 20 cm. The pebbles having porosity (φ) of 0.45 and 0.52 were, respectively, used in PB and PE. The fuel was supplied dropwise from the top through the PB and the combustion was occurred between PB and PE. Axial profiles of temperature along the burner length were measured to clarify the evaporation and combustion phenomena. The pollutant emission characteristics were monitored at the burner exit. From the experiment, it was found that the temperature profiles of both structures decreased with the three ways swirling air flows (QA) increasing. On the other hand, the temperature profiles increased with fuel heat input (QF). Obviously, the profile of the porous burner installed with PE was higher than that of the porous burner without PEKeywords: Liquid fuel, Porous burner, Temperature profile.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1751493 The Small Scale Effect on Nonlinear Vibration of Single Layer Graphene Sheets
Authors: E. Jomehzadeh, A.R. Saidi
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In the present article, nonlinear vibration analysis of single layer graphene sheets is presented and the effect of small length scale is investigated. Using the Hamilton's principle, the three coupled nonlinear equations of motion are obtained based on the von Karman geometrical model and Eringen theory of nonlocal continuum. The solutions of Free nonlinear vibration, based on a one term mode shape, are found for both simply supported and clamped graphene sheets. A complete analysis of graphene sheets with movable as well as immovable in-plane conditions is also carried out. The results obtained herein are compared with those available in the literature for classical isotropic rectangular plates and excellent agreement is seen. Also, the nonlinear effects are presented as functions of geometric properties and small scale parameter.Keywords: Small scale, Nonlinear vibration, Graphene sheet, Nonlocal continuum
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2324492 A New Approach to Steganography using Sinc-Convolution Method
Authors: Ahmad R. Naghsh-Nilchi, Latifeh Pourmohammadbagher
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Both image steganography and image encryption have advantages and disadvantages. Steganograhy allows us to hide a desired image containing confidential information in a covered or host image while image encryption is decomposing the desired image to a non-readable, non-comprehended manner. The encryption methods are usually much more robust than the steganographic ones. However, they have a high visibility and would provoke the attackers easily since it usually is obvious from an encrypted image that something is hidden! The combination of steganography and encryption will cover both of their weaknesses and therefore, it increases the security. In this paper an image encryption method based on sinc-convolution along with using an encryption key of 128 bit length is introduced. Then, the encrypted image is covered by a host image using a modified version of JSteg steganography algorithm. This method could be applied to almost all image formats including TIF, BMP, GIF and JPEG. The experiment results show that our method is able to hide a desired image with high security and low visibility.Keywords: Sinc Approximation, Image Encryption, Sincconvolution, Image Steganography, JSTEG.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1813491 Synthesis of Dispersion-Compensating Triangular Lattice Index-Guiding Photonic Crystal Fibers Using the Directed Tabu Search Method
Authors: F. Karim
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In this paper, triangular lattice index-guiding photonic crystal fibers (PCFs) are synthesized to compensate the chromatic dispersion of a single mode fiber (SMF-28) for an 80 km optical link operating at 1.55 µm, by using the directed tabu search algorithm. Hole-to-hole distance, circular air-hole diameter, solid-core diameter, ring number and PCF length parameters are optimized for this purpose. Three Synthesized PCFs with different physical parameters are compared in terms of their objective functions values, residual dispersions and compensation ratios.
Keywords: Triangular lattice index-guiding photonic crystal fiber, dispersion compensation, directed tabu search, synthesis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1296490 Experimental Investigation of the Transient Cooling Characteristics of an Industrial Glass Tempering Unit
Authors: Hilmi Yazici, Mehmet Akcay, Mustafa Golcu, Mehmet F. Koseoglu, Yakup Sekmen
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Energy consumption rate during the cooling process of industrial glass tempering process is considerably high. In this experimental study the effect of dimensionless jet to jet distance (S/D) and jet to plate distance (H/D) on the cooling time have been investigated. In the experiments 4 mm thick glass samples have been used. Cooling unit consists of 16 mutually placed seamless aluminum nozzles of 8 mm in diameter and 80 mm in length. Nozzles were in staggered arrangement. Experiments were conducted with circular jets for H/D values between 1 and 10, and for S/D values between 2 and 10. During the experiments Reynolds number has been kept constant at 30000. Experimental results showed that the longest cooling time with 87 seconds has been observed in the experiments for S/D=10 and H/D=10 values, while the shortest cooling time with 42.5 seconds has been measured in the experiments for S/D=2 and H/D=4 values.Keywords: Glass tempering, cooling, Reynolds number, nozzle
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1801489 On the Steady-State Performance Characteristics of Finite Hydrodynamic Journal Bearing under Micro-Polar Lubrication with Turbulent Effect
Authors: Subrata Das, Sisir Kumar Guha
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The objective of the present paper is to theoretically investigate the steady-state performance characteristics of journal bearing of finite width, operating with micropolar lubricant in a turbulent regime. In this analysis, the turbulent shear stress coefficients are used based on the Constantinescu’s turbulent model suggested by Taylor and Dowson with the assumption of parallel and inertia-less flow. The numerical solution of the modified Reynolds equation has yielded the distribution of film pressure which determines the static performance characteristics in terms of load capacity, attitude angle, end flow rate and frictional parameter at various values of eccentricity ratio, non-dimensional characteristics length, coupling number and Reynolds number.
Keywords: Hydrodynamic lubrication, steady-state, micropolar lubricant, turbulent.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2733488 The Comparison of Form Drag and Profile Dragof a Wind Turbine Blade Section in Pitching Oscillation
Authors: M. R. Soltani, M. Seddighi, M. Mahmoudi
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Extensive wind tunnel tests have been conducted to investigate the unsteady flow field over and behind a 2D model of a 660 kW wind turbine blade section in pitching motion. The surface pressure and wake dynamic pressure variation at a distance of 1.5 chord length from trailing edge were measured by pressure transducers during several oscillating cycles at 3 reduced frequencies and oscillating amplitudes. Moreover, form drag and linear momentum deficit are extracted and compared at various conditions. The results show that the wake velocity field and surface pressure of the model have similar behavior before and after the airfoil beyond the static stall angle of attack. In addition, the effects of reduced frequency and oscillation amplitudes are discussed.Keywords: Pitching motion, form drag, Profile drag, windturbine.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1979487 Experimental Investigation on the Effect of Bond Thickness on the Interface Behaviour of Fibre Reinforced Polymer Sheet Bonded to Timber
Authors: Abbas Vahedian, Rijun Shrestha, Keith Crews
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The bond mechanism between timber and fibre reinforced polymer (FRP) is relatively complex and is influenced by a number of variables including bond thickness, bond width, bond length, material properties, and geometries. This study investigates the influence of bond thickness on the behaviour of interface, failure mode, and bond strength of externally bonded FRP-to-timber interface. In the present study, 106 single shear joint specimens have been investigated. Experiment results showed that higher layers of FRP increase the ultimate load carrying capacity of interface; conversely, such increase led to decrease the slip of interface. Moreover, samples with more layers of FRPs may fail in a brittle manner without noticeable warning that collapse is imminent.Keywords: FRP, single shear test, bond thickness, bond strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 743486 Fast Calculation for Particle Interactions in SPH Simulations: Outlined Sub-domain Technique
Authors: Buntara Sthenly Gan, Naohiro Kawada
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A simple and easy algorithm is presented for a fast calculation of kernel functions which required in fluid simulations using the Smoothed Particle Hydrodynamic (SPH) method. Present proposed algorithm improves the Linked-list algorithm and adopts the Pair-Wise Interaction technique, which are widely used for evaluating kernel functions in fluid simulations using the SPH method. The algorithm is easy to be implemented without any complexities in programming. Some benchmark examples are used to show the simulation time saved by using the proposed algorithm. Parametric studies on the number of divisions for sub-domains, smoothing length and total amount of particles are conducted to show the effectiveness of the present technique. A compact formulation is proposed for practical usage.
Keywords: Technique, fluid simulation, smoothing particle hydrodynamic (SPH), particle interaction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1620485 Heavy Metals (Pb, Cu, Fe, and Zn) Level in Shellfish (Etheria elliptica), Water and Sediments of River Ogbese, Ondo State, Nigeria
Authors: O. O. Olawusi-Peters, O. E. Aguda, F. O. Okoye
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Investigations on the accumulation of heavy metals in water and sediments of river Ogbese were carried out between December 2010 and February 2011 using Atomic Absorption Spectrophotometer. Etheria elliptica a sessile organism was also used to determine the concentration of heavy metal in the aquatic environmental. In water, Cu had the highest concentration (0.55 – 0.13 mg/l ±0.1) while in sediments, the highest value obtained was in Fe (1.46-3.89mg/l±0.27). The minimum concentrations recorded were in Pb; which was below detectable level. The result also revealed that the shell accumulate more heavy metals than the flesh of the mussel with Cu in the shell exhibiting a negative correlation with all the metals in the flesh. However, the condition factor (K) value is 6.44, an indication of good health. The length-weight relationship is expressed as W = -0.48 x L 1.94 (r2 = 0.29) showing the growth pattern to be negatively allometric.Keywords: Condition factor, Etheria elliptica, heavy metals, River Ogbese.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2115484 Study on the Evaluation of the Chaotic Cipher System Using the Improved Volterra Filters and the RBFN Mapping
Authors: Hirotaka Watanabe, Takaaki Kondo, Daiki Yoshida, Ariyoshi Nakayama, Taichi Sato, Shuhei Kuriyama, Hiroyuki Kamata
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In this paper, we propose a chaotic cipher system consisting of Improved Volterra Filters and the mapping that is created from the actual voice by using Radial Basis Function Network. In order to achieve a practical system, the system supposes to use the digital communication line, such as the Internet, to maintain the parameter matching between the transmitter and receiver sides. Therefore, in order to withstand the attack from outside, it is necessary that complicate the internal state and improve the sensitivity coefficient. In this paper, we validate the robustness of proposed method from three perspectives of "Chaotic properties", "Randomness", "Coefficient sensitivity".
Keywords: Chaos cipher, 16-bit-length fixed point arithmetic, Volterra filter, Seacret communications, RBF Network
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1808483 Free Vibration Analysis of Functionally Graded Beams
Authors: Gholam Reza Koochaki
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This work presents the highly accurate numerical calculation of the natural frequencies for functionally graded beams with simply supported boundary conditions. The Timoshenko first order shear deformation beam theory and the higher order shear deformation beam theory of Reddy have been applied to the functionally graded beams analysis. The material property gradient is assumed to be in the thickness direction. The Hamilton-s principle is utilized to obtain the dynamic equations of functionally graded beams. The influences of the volume fraction index and thickness-to-length ratio on the fundamental frequencies are discussed. Comparison of the numerical results for the homogeneous beam with Euler-Bernoulli beam theory results show that the derived model is satisfactory.Keywords: Functionally graded beam, Free vibration, Hamilton's principle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2117482 Environmental Analysis of Springs in Urban Areas–A Methodological Proposal
Authors: Milton Pavezzi Netto, Gustavo D'Almeida Scarpinella, Ricardo Siloto da Silva
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The springs located in urban areas are the outpouring of surface water, which can serve as water supply, effluent receptors and important local macro-drainage elements. With unplanned occupation, non-compliance with environmental legislation and the importance of these water bodies, it is vital to analyze the springs within urban areas, considering the Brazilian forest code. This paper submits an analysis and discussion methodology proposal of environmental compliance functions of urban springs, by means of G.I.S. - Geographic Information System analysis - and in situ analysis. The case study included two springs which exhibit a history of occupation along its length, with different degrees of impact. The proposed method is effective and easy to apply, representing a powerful tool for analyzing the environmental conditions of springs in urban areas.Keywords: Springs, urban area, Brazilian forest code.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1582481 Monte Carlo Simulation of Copolymer Heterogeneity in Atom Transfer Radical Copolymerization of Styrene and N-Butyl Acrylate
Authors: Mohammad Najafi, Hossein Roghani-Mamaqani, Mehdi Salami-Kalajahi, Vahid Haddadi-Asl
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A high-performance Monte Carlo simulation, which simultaneously takes diffusion-controlled and chain-length-dependent bimolecular termination reactions into account, is developed to simulate atom transfer radical copolymerization of styrene and nbutyl acrylate. As expected, increasing initial feed fraction of styrene raises the fraction of styrene-styrene dyads (fAA) and reduces that of n-butyl acrylate dyads (fBB). The trend of variation in randomness parameter (fAB) during the copolymerization also varies significantly. Also, there is a drift in copolymer heterogeneity and the highest drift occurs in the initial feeds containing lower percentages of styrene, i.e. 20% and 5%.Keywords: Atom Transfer Radical Copolymerization, MonteCarlo Simulation, Copolymer Heterogeneity, Styrene n-ButylAcrylate
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1594480 Automatic Text Summarization
Authors: Mohamed Abdel Fattah, Fuji Ren
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This work proposes an approach to address automatic text summarization. This approach is a trainable summarizer, which takes into account several features, including sentence position, positive keyword, negative keyword, sentence centrality, sentence resemblance to the title, sentence inclusion of name entity, sentence inclusion of numerical data, sentence relative length, Bushy path of the sentence and aggregated similarity for each sentence to generate summaries. First we investigate the effect of each sentence feature on the summarization task. Then we use all features score function to train genetic algorithm (GA) and mathematical regression (MR) models to obtain a suitable combination of feature weights. The proposed approach performance is measured at several compression rates on a data corpus composed of 100 English religious articles. The results of the proposed approach are promising.Keywords: Automatic Summarization, Genetic Algorithm, Mathematical Regression, Text Features.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2321479 Bee Optimized Fuzzy Geographical Routing Protocol for VANET
Authors: P. Saravanan, T. Arunkumar
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Vehicular Adhoc Network (VANET) is a new technology which aims to ensure intelligent inter-vehicle communications, seamless internet connectivity leading to improved road safety, essential alerts, and access to comfort and entertainment. VANET operations are hindered by mobile node’s (vehicles) uncertain mobility. Routing algorithms use metrics to evaluate which path is best for packets to travel. Metrics like path length (hop count), delay, reliability, bandwidth, and load determine optimal route. The proposed scheme exploits link quality, traffic density, and intersections as routing metrics to determine next hop. This study enhances Geographical Routing Protocol (GRP) using fuzzy controllers while rules are optimized with Bee Swarm Optimization (BSO). Simulations results are compared to conventional GRP.
Keywords: Bee Swarm Optimization (BSO), Geographical Routing Protocol (GRP), Vehicular Adhoc Network (VANET).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2446