Search results for: general solution
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10075

Search results for: general solution

9865 Some Basic Problems for the Elastic Material with Voids in the Case of Approximation N=1 of Vekua's Theory

Authors: Bakur Gulua

Abstract:

In this work, we consider some boundary value problems for the plate. The plate is the elastic material with voids. The state of plate equilibrium is described by the system of differential equations that is derived from three-dimensional equations of equilibrium of an elastic material with voids (Cowin-Nunziato model) by Vekua's reduction method. Its general solution is represented by means of analytic functions of a complex variable and solutions of Helmholtz equations. The problem is solved analytically by the method of the theory of functions of a complex variable.

Keywords: the elastic material with voids, boundary value problems, Vekua's reduction method, a complex variable

Procedia PDF Downloads 93
9864 Reduced General Dispersion Model in Cylindrical Coordinates and Isotope Transient Kinetic Analysis in Laminar Flow

Authors: Masood Otarod, Ronald M. Supkowski

Abstract:

This abstract discusses a method that reduces the general dispersion model in cylindrical coordinates to a second order linear ordinary differential equation with constant coefficients so that it can be utilized to conduct kinetic studies in packed bed tubular catalytic reactors at a broad range of Reynolds numbers. The model was tested by 13CO isotope transient tracing of the CO adsorption of Boudouard reaction in a differential reactor at an average Reynolds number of 0.2 over Pd-Al2O3 catalyst. Detailed experimental results have provided evidence for the validity of the theoretical framing of the model and the estimated parameters are consistent with the literature. The solution of the general dispersion model requires the knowledge of the radial distribution of axial velocity. This is not always known. Hence, up until now, the implementation of the dispersion model has been largely restricted to the plug-flow regime. But, ideal plug-flow is impossible to achieve and flow regimes approximating plug-flow leave much room for debate as to the validity of the results. The reduction of the general dispersion model transpires as a result of the application of a factorization theorem. Factorization theorem is derived from the observation that a cross section of a catalytic bed consists of a solid phase across which the reaction takes place and a void or porous phase across which no significant measure of reaction occurs. The disparity in flow and the heterogeneity of the catalytic bed cause the concentration of reacting compounds to fluctuate radially. These variabilities signify the existence of radial positions at which the radial gradient of concentration is zero. Succinctly, factorization theorem states that a concentration function of axial and radial coordinates in a catalytic bed is factorable as the product of the mean radial cup-mixing function and a contingent dimensionless function. The concentration of adsorbed compounds are also factorable since they are piecewise continuous functions and suffer the same variability but in the reverse order of the concentration of mobile phase compounds. Factorability is a property of packed beds which transforms the general dispersion model to an equation in terms of the measurable mean radial cup-mixing concentration of the mobile phase compounds and mean cross-sectional concentration of adsorbed species. The reduced model does not require the knowledge of the radial distribution of the axial velocity. Instead, it is characterized by new transport parameters so denoted by Ωc, Ωa, Ωc, and which are respectively denominated convection coefficient cofactor, axial dispersion coefficient cofactor, and radial dispersion coefficient cofactor. These cofactors adjust the dispersion equation as compensation for the unavailability of the radial distribution of the axial velocity. Together with the rest of the kinetic parameters they can be determined from experimental data via an optimization procedure. Our data showed that the estimated parameters Ωc, Ωa Ωr, are monotonically correlated with the Reynolds number. This is expected to be the case based on the theoretical construct of the model. Computer generated simulations of methanation reaction on nickel provide additional support for the utility of the newly conceptualized dispersion model.

Keywords: factorization, general dispersion model, isotope transient kinetic, partial differential equations

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9863 Protection of Television Programme Formats in Comparative Law

Authors: Mustafa Arikan, Ibrahim Ercan

Abstract:

In this paper, protection of program formats was investigated in terms of program formats. Protection of program formats was studied in the French Law in the sense of competition law and CPI. Since the English Judicial system exhibits differences from the legal system of Continental Europe, its investigation bears a special significance. The subject was also handled in German Law at length. Indeed, German Law was investigated in detail within the overall framework of the study. Here, the court decisions in the German Law and the views in the doctrine were expressed in general. There are many court decisions in the American legal system concerning the subject. These decisions also present alternatives in terms of a solution to the problem.

Keywords: comparative law, protection of television programme formats, intellectual property, american legal system

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9862 The Effect of the Flow Pipe Diameter on the Rheological Behavior of a Polymeric Solution (CMC)

Authors: H. Abchiche, M. Mellal

Abstract:

The aim of this work is to study the parameters that influence the rheological behavior of a complex fluid (sodium Carboxyméthylcellulose solution), on a capillary rheometer. An installation has been made to be able to vary the diameter of trial conducts. The obtained results allowed us to deduce that: the diameter of trial conducts have a remarkable effect on the rheological responds.

Keywords: bingham’s fluid, CMC, cylindrical conduit, rheological behavior

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9861 Recovery of Draw Solution in Forward Osmosis by Direct Contact Membrane Distillation

Authors: Su-Thing Ho, Shiao-Shing Chen, Hung-Te Hsu, Saikat Sinha Ray

Abstract:

Forward osmosis (FO) is an emerging technology for direct and indirect potable water reuse application. However, successful implementation of FO is still hindered by the lack of draw solution recovery with high efficiency. Membrane distillation (MD) is a thermal separation process by using hydrophobic microporous membrane that is kept in sandwich mode between warm feed stream and cold permeate stream. Typically, temperature difference is the driving force of MD which attributed by the partial vapor pressure difference across the membrane. In this study, the direct contact membrane distillation (DCMD) system was used to recover diluted draw solution of FO. Na3PO4 at pH 9 and EDTA-2Na at pH 8 were used as the feed solution for MD since it produces high water flux and minimized salt leakage in FO process. At high pH, trivalent and tetravalent ions are much easier to remain at draw solution side in FO process. The result demonstrated that PTFE with pore size of 1 μm could achieve the highest water flux (12.02 L/m2h), followed by PTFE 0.45 μm (10.05 L/m2h), PTFE 0.1 μm (7.38 L/m2h) and then PP (7.17 L/m2h) while using 0.1 M Na3PO4 draw solute. The concentration of phosphate and conductivity in the PTFE (0.45 μm) permeate were low as 1.05 mg/L and 2.89 μm/cm respectively. Although PTFE with the pore size of 1 μm could obtain the highest water flux, but the concentration of phosphate in permeate was higher than other kinds of MD membranes. This study indicated that four kinds of MD membranes performed well and PTFE with the pore size of 0.45 μm was the best among tested membranes to achieve high water flux and high rejection of phosphate (99.99%) in recovery of diluted draw solution. Besides that, the results demonstrate that it can obtain high water flux and high rejection of phosphate when operated with cross flow velocity of 0.103 m/s with Tfeed of 60 ℃ and Tdistillate of 20 ℃. In addition to that, the result shows that Na3PO4 is more suitable for recovery than EDTA-2Na. Besides that, while recovering the diluted Na3PO4, it can obtain the high purity of permeate water. The overall performance indicates that, the utilization of DCMD is a promising technology to recover the diluted draw solution for FO process.

Keywords: membrane distillation, forward osmosis, draw solution, recovery

Procedia PDF Downloads 159
9860 Solution to Riemann Hypothesis Critical Strip Zone Using Non-Linear Complex Variable Functions

Authors: Manojkumar Sabanayagam

Abstract:

The Riemann hypothesis is an unsolved millennium problem and the search for a solution to the Riemann hypothesis is to study the pattern of prime number distribution. The scope of this paper is to identify the solution for the critical strip and the critical line axis, which has the non-trivial zero solutions using complex plane functions. The Riemann graphical plot is constructed using a linear complex variable function (X+iY) and is applicable only when X>1. But the investigation shows that complex variable behavior has two zones. The first zone is the transformation zone, where the definition of the complex plane should be a non-linear variable which is the critical strip zone in the graph (X=0 to 1). The second zone is the transformed zone (X>1) defined using linear variables conventionally. This paper deals with the Non-linear function in the transformation zone derived using cosine and sinusoidal time lag w.r.t imaginary number ‘i’. The alternate complex variable (Cosθ+i Sinθ) is used to understand the variables in the critical strip zone. It is concluded that the non-trivial zeros present in the Real part 0.5 are because the linear function is not the correct approach in the critical strip. This paper provides the solution to Reimann's hypothesis.

Keywords: Reimann hypothesis, critical strip, complex plane, transformation zone

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9859 Limit State of Heterogeneous Smart Structures under Unknown Cyclic Loading

Authors: M. Chen, S-Q. Zhang, X. Wang, D. Tate

Abstract:

This paper presents a numerical solution, namely limit and shakedown analysis, to predict the safety state of smart structures made of heterogeneous materials under unknown cyclic loadings, for instance, the flexure hinge in the micro-positioning stage driven by piezoelectric actuator. In combination of homogenization theory and finite-element method (FEM), the safety evaluation problem is converted to a large-scale nonlinear optimization programming for an acceptable bounded loading as the design reference. Furthermore, a general numerical scheme integrated with the FEM and interior-point-algorithm based optimization tool is developed, which makes the practical application possible.

Keywords: limit state, shakedown analysis, homogenization, heterogeneous structure

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9858 Nonlinear Mathematical Model of the Rotor Motion in a Thin Hydrodynamic Gap

Authors: Jaroslav Krutil, Simona Fialová, , František Pochylý

Abstract:

A nonlinear mathematical model of mutual fluid-structure interaction is presented in the work. The model is applicable to the general shape of sealing gaps. An in compressible fluid and turbulent flow is assumed. The shaft carries a rotational and procession motion, the gap is axially flowed through. The achieved results of the additional mass, damping and stiffness matrices may be used in the solution of the rotor dynamics. The usage of this mathematical model is expected particularly in hydraulic machines. The method of control volumes in the ANSYS Fluent was used for the simulation. The obtained results of the pressure and velocity fields are used in the mathematical model of additional effects.

Keywords: nonlinear mathematical model, CFD modeling, hydrodynamic sealing gap, matrices of mass, stiffness, damping

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9857 Low Temperature Solution Processed Solar Cell Based on ITO/PbS/PbS:Bi3+ Heterojunction

Authors: M. Chavez, H. Juarez, M. Pacio, O. Portillo

Abstract:

PbS chemical bath heterojunction sollar cells have shown significant improvements in performance. Here we demonstrate a solar cell based on the heterojunction formed between PbS layer and PbS:Bi3+ thin films that are deposited via solution process at 40°C. The device achieve an current density of 4 mA/cm2. The simple and low-cost deposition method of PbS:Bi3+ films is promising for the fabrication.

Keywords: PbS doped, Bismuth, solar cell, thin films

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9856 An Improved Discrete Version of Teaching–Learning-Based ‎Optimization for Supply Chain Network Design

Authors: Ehsan Yadegari

Abstract:

While there are several metaheuristics and exact approaches to solving the Supply Chain Network Design (SCND) problem, there still remains an unfilled gap in using the Teaching-Learning-Based Optimization (TLBO) algorithm. The algorithm has demonstrated desirable results with problems with complicated combinational optimization. The present study introduces a Discrete Self-Study TLBO (DSS-TLBO) with priority-based solution representation that can solve a supply chain network configuration model to lower the total expenses of establishing facilities and the flow of materials. The network features four layers, namely suppliers, plants, distribution centers (DCs), and customer zones. It is designed to meet the customer’s demand through transporting the material between layers of network and providing facilities in the best economic Potential locations. To have a higher quality of the solution and increase the speed of TLBO, a distinct operator was introduced that ensures self-adaptation (self-study) in the algorithm based on the four types of local search. In addition, while TLBO is used in continuous solution representation and priority-based solution representation is discrete, a few modifications were added to the algorithm to remove the solutions that are infeasible. As shown by the results of experiments, the superiority of DSS-TLBO compared to pure TLBO, genetic algorithm (GA) and firefly Algorithm (FA) was established.

Keywords: supply chain network design, teaching–learning-based optimization, improved metaheuristics, discrete solution representation

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9855 Generalized Limit Equilibrium Solution for the Lateral Pile Capacity Problem

Authors: Tomer Gans-Or, Shmulik Pinkert

Abstract:

The determination of lateral pile capacity per unit length is a key aspect in geotechnical engineering. Traditional approaches for assessing piles lateral capacity in cohesive soils involve the application of upper-bound and lower-bound plasticity theorems. However, a comprehensive solution encompassing the entire spectrum of soil strength parameters, particularly in frictional soils with or without cohesion, is still lacking. This research introduces an innovative implementation of the slice method limit equilibrium solution for lateral capacity assessment. For any given numerical discretization of the soil's domain around the pile, the lateral capacity evaluation is based on mobilized strength concept. The critical failure geometry is then found by a unique optimization procedure which includes both factor of safety minimization and geometrical optimization. The robustness of this suggested methodology is that the solution is independent of any predefined assumptions. Validation of the solution is accomplished through a comparison with established plasticity solutions for cohesive soils. Furthermore, the study demonstrates the applicability of the limit equilibrium method to address unresolved cases related to frictional and cohesive-frictional soils. Beyond providing capacity values, the method enables the utilization of the mobilized strength concept to generate safety-factor distributions for scenarios representing pre-failure states.

Keywords: lateral pile capacity, slice method, limit equilibrium, mobilized strength

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9854 Development of Extended Trapezoidal Method for Numerical Solution of Volterra Integro-Differential Equations

Authors: Fuziyah Ishak, Siti Norazura Ahmad

Abstract:

Volterra integro-differential equations appear in many models for real life phenomena. Since analytical solutions for this type of differential equations are hard and at times impossible to attain, engineers and scientists resort to numerical solutions that can be made as accurately as possible. Conventionally, numerical methods for ordinary differential equations are adapted to solve Volterra integro-differential equations. In this paper, numerical solution for solving Volterra integro-differential equation using extended trapezoidal method is described. Formulae for the integral and differential parts of the equation are presented. Numerical results show that the extended method is suitable for solving first order Volterra integro-differential equations.

Keywords: accuracy, extended trapezoidal method, numerical solution, Volterra integro-differential equations

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9853 Path-Tracking Controller for Tracked Mobile Robot on Rough Terrain

Authors: Toshifumi Hiramatsu, Satoshi Morita, Manuel Pencelli, Marta Niccolini, Matteo Ragaglia, Alfredo Argiolas

Abstract:

Automation technologies for agriculture field are needed to promote labor-saving. One of the most relevant problems in automated agriculture is represented by controlling the robot along a predetermined path in presence of rough terrain or incline ground. Unfortunately, disturbances originating from interaction with the ground, such as slipping, make it quite difficult to achieve the required accuracy. In general, it is required to move within 5-10 cm accuracy with respect to the predetermined path. Moreover, lateral velocity caused by gravity on the incline field also affects slipping. In this paper, a path-tracking controller for tracked mobile robots moving on rough terrains of incline field such as vineyard is presented. The controller is composed of a disturbance observer and an adaptive controller based on the kinematic model of the robot. The disturbance observer measures the difference between the measured and the reference yaw rate and linear velocity in order to estimate slip. Then, the adaptive controller adapts “virtual” parameter of the kinematics model: Instantaneous Centers of Rotation (ICRs). Finally, target angular velocity reference is computed according to the adapted parameter. This solution allows estimating the effects of slip without making the model too complex. Finally, the effectiveness of the proposed solution is tested in a simulation environment.

Keywords: the agricultural robot, autonomous control, path-tracking control, tracked mobile robot

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9852 Electrochemical Corrosion and Mechanical Properties of Structural Materials for Oil and Gas Applications in Simulated Deep-Sea Well Environments

Authors: Turin Datta, Kisor K. Sahu

Abstract:

Structural materials used in today’s oil and gas exploration and drilling of both onshore and offshore oil and gas wells must possess superior tensile properties, excellent resistance to corrosive degradation that includes general, localized (pitting and crevice) and environment assisted cracking such as stress corrosion cracking and hydrogen embrittlement. The High Pressure and High Temperature (HPHT) wells are typically operated at temperature and pressure that can exceed 300-3500F and 10,000psi (69MPa) respectively which necessitates the use of exotic materials in these exotic sources of natural resources. This research investigation is focussed on the evaluation of tensile properties and corrosion behavior of AISI 4140 High-Strength Low Alloy Steel (HSLA) possessing tempered martensitic microstructure and Duplex 2205 Stainless Steel (DSS) having austenitic and ferritic phase. The selection of this two alloys are primarily based on economic considerations as 4140 HSLA is cheaper when compared to DSS 2205. Due to the harsh aggressive chemical species encountered in deep oil and gas wells like chloride ions (Cl-), carbon dioxide (CO2), hydrogen sulphide (H2S) along with other mineral organic acids, DSS 2205, having a dual-phase microstructure can mitigate the degradation resulting from the presence of both chloride ions (Cl-) and hydrogen simultaneously. Tensile properties evaluation indicates a ductile failure of DSS 2205 whereas 4140 HSLA exhibit quasi-cleavage fracture due to the phenomenon of ‘tempered martensitic embrittlement’. From the potentiodynamic polarization testing, it is observed that DSS 2205 has higher corrosion resistance than 4140 HSLA; the former exhibits passivity signifying resistance to localized corrosion while the latter exhibits active dissolution in all the environmental parameters space that was tested. From the Scanning Electron Microscopy (SEM) evaluation, it is understood that stable pits appear in DSS 2205 only when the temperature exceeds the critical pitting temperature (CPT). SEM observation of the corroded 4140 HSLA specimen tested in aqueous 3.5 wt.% NaCl solution reveals intergranular cracking which appears due to the adsorption and diffusion of hydrogen during polarization, thus, causing hydrogen-induced cracking/hydrogen embrittlement. General corrosion testing of DSS 2205 in acidic brine (pH~3.0) solution at ambient temperature using coupons indicate no weight loss even after three months whereas the corrosion rate of AISI 4140 HSLA is significantly higher after one month of testing.

Keywords: DSS 2205, polarization, pitting, SEM

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9851 Youth Voter Turnout in Jamaica: A Case Study of the 2016 General Election

Authors: Tracy-Ann Johnson-Myers

Abstract:

Since the early 1990’s voter turnout in Jamaica has been abysmal. More troubling, the group less interested in voting are the ‘articulate minority’ (educated youths, aged 18-35). Using surveys, media commentaries and data from the Electoral Commission of Jamaica, this study explores the relationship between educated youths and traditional politics in Jamaica. Specifically, it raises questions about why the ‘articulate minority’ did not vote in the 2016 general election. This will be done by highlighting the political and socio-economic reasons affecting their participation in the electoral process, their opinions of who is responsible for low voter turnout in Jamaica, and what they think needs to be done to encourage people in general to vote. The findings reveal that lack of interest in the democratic and electoral process by the ‘articulate minority’ is due to their growing distrust of politicians and political parties, and lack of confidence in the political process.

Keywords: articulate minority, Jamaica, voter apathy, voter turnout

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9850 Using Cooperation Approaches at Different Levels of Artificial Bee Colony Method

Authors: Vahid Zeighami, Mohsen Ghsemi, Reza Akbari

Abstract:

In this work, a Multi-Level Artificial Bee Colony (called MLABC) is presented. In MLABC two species are used. The first species employs n colonies in which each of the them optimizes the complete solution vector. The cooperation between these colonies is carried out by exchanging information through a leader colony, which contains a set of elite bees. The second species uses a cooperative approach in which the complete solution vector is divided to k sub-vectors, and each of these sub-vectors is optimized by a a colony. The cooperation between these colonies is carried out by compiling sub-vectors into the complete solution vector. Finally, the cooperation between two species is obtained by exchanging information between them. The proposed algorithm is tested on a set of well known test functions. The results show that MLABC algorithms provide efficiency and robustness to solve numerical functions.

Keywords: artificial bee colony, cooperative, multilevel cooperation, vector

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9849 An Advanced Method of Plant Preservation and Colour Retention of Herbarium Specimens

Authors: Abduraheem K., Suboohi Nasrin

Abstract:

Herbaria are specimens of preserved plants, which are very delicate and cellulosic in nature. While these collections are very useful for the enrichment of knowledge and are considered as natural heritage of our entire world, it is very important to preserve and conserve them. The significance is not only to prevent the herbaria from the deterioration of biological agencies but also to preserve its colours and retain natural colour. Colour is not only characteristic of a plant, but it can also help to identify closely related species or to distinguish a plant from a collection of herbaria. Keeping this in mind, a selective solution has been prepared for the conservation and preservation of herbarium in the present study. In this, the quantity of all the selected chemicals, i.e., formaldehyde and copper sulphate was kept constant, and the solution was prepared by dissolving it in distilled water by increasing the amount of picric acid (1, 2, 3, 4, and 5 ml). Fresh specimens of roses and bougainvillea were washed with distilled water and kept in the above solution for 10 to 15 minutes at room temperature. After 10 minutes, the specimen was removed from the solution, dried with the help of paper, and then pressed under the plant press. Blotting sheets were used to absorb the moisture content and were changed every 2 to 3 days to protect against fungal growth. The results revealed that all solutions had insecticidal properties and protected the herbarium specimen against pests. While in the case of colour retention, solution-1 and 2 were not satisfactory colour preservation, and solutions-3 and 5 maintained the colour of rose and bougainvillea leaves for 15 to 20 days and for a month, respectively. After that, the colour begins to fade, and the process is faster in rose leaves than in bougainvillea. And it was also observed that the colour of young leaves started to fade before that of older leaves. When the leaves of rose and bougainvillea are treated with Solution-4, then the colour of rose leaves is maintained for six months.

Keywords: solutions, colour retention, preservation and conservation, leaves of roses and bougainvillea

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9848 Undoped and Fluorine Doped Zinc Oxide (ZnO:F) Thin Films Deposited by Ultrasonic Chemical Spray: Effect of the Solution on the Electrical and Optical Properties

Authors: E. Chávez-Vargas, M. de la L. Olvera-Amador, A. Jimenez-Gonzalez, A. Maldonado

Abstract:

Undoped and fluorine doped zinc oxide (ZnO) thin films were deposited on sodocalcic glass substrates by the ultrasonic chemical spray technique. As the main goal is the manufacturing of transparent electrodes, the effects of both the solution composition and the substrate temperature on both the electrical and optical properties of ZnO thin films were studied. As a matter of fact, the effect of fluorine concentration ([F]/[F+Zn] at. %), solvent composition (acetic acid, water, methanol ratios) and ageing time, regarding solution composition, were varied. In addition, the substrate temperature and the deposition time, regarding the chemical spray technique, were also varied. Structural studies confirm the deposition of polycrystalline, hexagonal, wurtzite type, ZnO. The results show that the increase of ([F]/[F+Zn] at. %) ratio in the solution, decreases the sheet resistance, RS, of the ZnO:F films, reaching a minimum, in the order of 1.6 Ωcm, at 60 at. %; further increase in the ([F]/[F+Zn]) ratio increases the RS of the films. The same trend occurs with the variation in substrate temperature, as a minimum RS of ZnO:F thin films was encountered when deposited at TS= 450 °C. ZnO:F thin films deposited with aged solution show a significant decrease in the RS in the order of 100 ΩS. The transmittance of the films was also favorable affected by the solvent ratio and, more significantly, by the ageing of the solution. The whole evaluation of optical and electrical characteristics of the ZnO:F thin films deposited under different conditions, was done under Haacke’s figure of Merit in order to have a clear and quantitative trend as transparent conductors application.

Keywords: zinc oxide, ZnO:F, TCO, Haacke’s figure of Merit

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9847 Heat Transfer Characteristics of Film Condensation

Authors: M. Mosaad, J. H. Almutairi, A. S. Almutairi

Abstract:

In this paper, saturated-vapour film condensation on a vertical wall with the backside cooled by forced convection is analyzed as a conjugate problem. In the analysis, the temperature and heat flux at the wall sides are assumed unknown and determined from the solution. The model is presented in a dimensionless form to take a broad view of the solution. The dimensionless variables controlling this coupled heat transfer process are discovered from the analysis. These variables explain the relative impact of the interactive heat transfer mechanisms of forced convection and film condensation. The study shows that the conjugate treatment of film condensation process yields results different from that predicted by a non-conjugate Nusselt-type solution, wherein the effect of the cooling fluid is neglected.

Keywords: film condensation, forced convection, coupled heat transfer, analytical modelling

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9846 Preparation of Catalyst-Doped TiO2 Nanotubes by Single Step Anodization and Potential Shock

Authors: Hyeonseok Yoo, Kiseok Oh, Jinsub Choi

Abstract:

Titanium oxide nanotubes have attracted great attention because of its photocatalytic activity and large surface area. For enhancing electrochemical properties, catalysts should be doped into the structure because titanium oxide nanotubes themselves have low electroconductivity and catalytic activity. It has been reported that Ru and Ir doped titanium oxide electrodes exhibit high efficiency and low overpotential in the oxygen evolution reaction (OER) for water splitting. In general, titanium oxide nanotubes with high aspect ratio cannot be easily doped by conventional complex methods. Herein, two types of facile routes, namely single step anodization and potential shock, for Ru doping into high aspect ratio titanium oxide nanotubes are introduced in detail. When single step anodization was carried out, stability of electrodes were increased. However, onset potential was shifted to anodic direction. On the other hand, when high potential shock voltage was applied, a large amount of ruthenium/ruthenium oxides were doped into titanium oxide nanotubes and thick barrier oxide layers were formed simultaneously. Regardless of doping routes, ruthenium/ ruthenium oxides were homogeneously doped into titanium oxide nanotubes. In spite of doping routes, doping in aqueous solution generally led to incorporate high amount of Ru in titanium oxide nanotubes, compared to that in non-aqueous solution. The amounts of doped catalyst were analyzed by X-ray photoelectron spectroscopy (XPS). The optimum condition for water splitting was investigated in terms of the amount of doped Ru and thickness of barrier oxide layer.

Keywords: doping, potential shock, single step anodization, titanium oxide nanotubes

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9845 The Examination of Organizational DNA of General Directorate of Youth and Sport Organization of Fars Province Based on Hnald Model

Authors: Mehdi Rastegari Ghiri, Mohammad Reza Baradaran, Zahra Mirsanjari

Abstract:

The aim of the present study was the investigation of DNA Corporate General Administration of Sports and Youth in Fars province. The descriptive research method is a survey that was conducted by field survey. For data collection, questionnaires were used that designed based on Hnald and Silverman model. In this model the organizational DNA model is stated in four types: objective, individualistic, field-oriented and Spiritual. The reliability of the questionnaire by the researcher obtained by using Cronbach's alpha equal to 89/0 respectively. The statistical population includes all managers and specialists of Fars Province Directorate of Youth and Sport that 48 of them were selected as the samples of the research. The results showed the organizational DNA Directorate General for Youth and Sports Organization of Fars province has a field –oriented and nearly field-oriented DNA.

Keywords: organizational, DNA, Hnald, Silverman model

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9844 On a Continuous Formulation of Block Method for Solving First Order Ordinary Differential Equations (ODEs)

Authors: A. M. Sagir

Abstract:

The aim of this paper is to investigate the performance of the developed linear multistep block method for solving first order initial value problem of Ordinary Differential Equations (ODEs). The method calculates the numerical solution at three points simultaneously and produces three new equally spaced solution values within a block. The continuous formulations enable us to differentiate and evaluate at some selected points to obtain three discrete schemes, which were used in block form for parallel or sequential solutions of the problems. A stability analysis and efficiency of the block method are tested on ordinary differential equations involving practical applications, and the results obtained compared favorably with the exact solution. Furthermore, comparison of error analysis has been developed with the help of computer software.

Keywords: block method, first order ordinary differential equations, linear multistep, self-starting

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9843 Surprising Behaviour of Kaolinitic Soils under Alkaline Environment

Authors: P. Hari Prasad Reddy, Shimna Paulose, V. Sai Kumar, C. H. Rama Vara Prasad

Abstract:

Soil environment gets contaminated due to rapid industrialisation, agricultural-chemical application and improper disposal of waste generated by the society. Unexpected volume changes can occur in soil in the presence of certain contaminants usually after the long duration of interaction. Alkali is one of the major soil contaminant that has a considerable effect on behaviour of soils and capable of inducing swelling potential in soil. Chemical heaving of clayey soils occurs when they are wetted by aqueous solutions of alkalis. Mineralogical composition of the soil is one of the main factors influencing soil- alkali interaction. In the present work, studies are carried out to understand the swell potential of soils due to soil-alkali interaction with different concentrations of NaOH solution. Locally available soil, namely, red earth containing kaolinite which is of non-swelling nature is selected for the study. In addition to this, two commercially available clayey soils, namely ball clay and china clay containing mainly of kaolinite are selected to understand the effect of alkali interaction in various kaolinitic soils. Non-swelling red earth shows maximum swell at lower concentrations of alkali solution (0.1N) and a slightly decreasing trend of swelling with further increase in concentration (1N, 4N, and 8N). Marginal decrease in swell potential with increase in concentration indicates that the increased concentration of alkali solution exists as free solution in case of red earth. China clay and ball clay both falling under kaolinite group of clay minerals, show swelling with alkaline solution. At lower concentrations of alkali solution both the soils shows similar swell behaviour, but at higher concentration of alkali solution ball clay shows high swell potential compared to china clay which may be due to lack of well ordered crystallinity in ball clay compared to china clay. The variations in the results obtained were corroborated by carrying XRD and SEM studies.

Keywords: alkali, kaolinite, swell potential, XRD, SEM

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9842 Universal Design for Learning: Its Impact for Enhanced Performance in General Psychology

Authors: Jose Gay D. Gallego

Abstract:

This study examined the learning performance in General Psychology of 297 freshmen of the CPSU-Main through the Pre and Post Tests. The instructional intervention via Universal Design for Learning (UDL) was applied to 33% (97 out of 297) of these freshmen as the Treatment Group while the 67% (200) belonged to the Control Group for traditional instructions. Statistical inferences utilized one-way Analysis of Variance for mean differences; Pearson R Correlations for bivariate relationships, and; Factor Analysis for significant components that contributed most to the Universal Design for Learning instructions. Findings showed very high levels of students’ acquired UDL skills. Results in the pre test in General Psychology, respectively, were low and average when grouped into low and high achievers. There was no significant mean difference in the acquired nine UDL components when categorized into seven colleges to generalize that between colleges they were on the same very high levels. Significant differences were found in three test areas in General Psychology in eight colleges whose students in College of teacher education taking the lead in the learning performance. Significant differences were also traced in the post test in favor of the students in the treatment group. This proved that UDL really impacted the learning performance of the low achieving students. Significant correlations were revealed between the components of UDL and General Psychology. There were twenty four significant itemized components that contributed most to UDL instructional interventions. Implications were emphasized to maximizing the principles of UDL with the contention of thoughtful planning related to the four curricular pillars of UDL: (a) instructional goals, (b) instructional delivery methods, (c) instructional materials, and (d) student assessments.

Keywords: universal design for learning, enhanced performance, teaching innovation, technology in education, social science area

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9841 Immediate Geometric Solution of Irregular Quadrilaterals: A Digital Tool Applied to Topography

Authors: Miguel Mariano Rivera Galvan

Abstract:

The purpose of this research was to create a digital tool by which users can obtain an immediate and accurate solution of the angular characteristics of an irregular quadrilateral. The development of this project arose because of the frequent absence of a polygon’s geometric information in land ownership accreditation documents. The researcher created a mathematical model using a linear approximation iterative method, employing various disciplines and techniques including trigonometry, geometry, algebra, and topography. This mathematical model uses as input data the surface of the quadrilateral, as well as the length of its sides, to obtain its interior angles and make possible its representation in a coordinate system. The results are as accurate and reliable as the user requires, offering the possibility of using this tool as a support to develop future engineering and architecture projects quickly and reliably.

Keywords: digital tool, geometry, mathematical model, quadrilateral, solution

Procedia PDF Downloads 113
9840 Microstructure and Mechanical Properties of Boron-Containing AZ91D Mg Alloys

Authors: Ji Chan Kim, Seok Hong Min, Tae Kwon Ha

Abstract:

Effect of boron addition on the microstructure and mechanical properties of AZ91D Mg alloy was investigated in this study. Through calculation of phase equilibria, carried out by using FactSage® and FTLite database, solution treatment temperature was decided as 420 °C where supersaturated solid solution can be obtained. Solid solution treatment was conducted at 420 °C for 24 hrs followed by hot rolling at 420 °C and the total reduction was about 60%. Recrystallization heat treatment was followed at 420 °C for 6 hrs to obtain equiaxed microstructure. After recrystallization treatment, aging heat treatment was conducted at temperature of 200 °C for time intervals from 1 min to 200 hrs and hardness of each condition was measured by micro-Vickers method. Peak hardness was observed after 20 hrs. Tensile tests were also conducted on the specimens aged for various time intervals and the results were compared with hardness.

Keywords: AZ91D Mg alloy, boron, heat treatment, microstructure, mechanical properties, hardness

Procedia PDF Downloads 277
9839 Preparation of Chromium Nanoparticles on Carbon Substrate from Tannery Waste Solution by Chemical Method Compared to Electrokinetic Process

Authors: Mahmoud A. Rabah, Said El Sheikh

Abstract:

This work shows the preparation of chromium nanoparticles from tannery waste solution on glassy carbon by chemical method compared to electrokinetic process. The waste solution contains free and soluble fats, calcium, iron, magnesium and high sodium in addition to the chromium ions. Filtration helps removal of insoluble matters. Diethyl ether successfully extracted soluble fats. The method started by removing calcium as insoluble oxalate salts at hot conditions in a faint acidic medium. The filtrate contains iron, magnesium, chromium ions and sodium chloride in excess. Chromium was separated selectively as insoluble hydroxide sol-gel at pH 6.5, filtered and washed with distilled water. Part of the gel reacted with sulfuric acid to produce chromium sulfate solution having 15-25 g/L concentration. Electrokinetic deposition of chromium nanoparticles on a carbon cathode was carried out using platinum anode under different galvanostatic conditions. The chemical method involved impregnating the carbon specimens with chromium hydroxide gel followed by reduction using hydrazine hydrate or by thermal reduction using hydrogen gas at 1250°C. Chromium grain size was characterized by TEM, FT-IR and SEM. Properties of the Cr grains were correlated to the conditions of the preparation process. Electrodeposition was found to control chromium particles to be more identical in size and shape as compared to the chemical method.

Keywords: chromium, electrodeposition, nanoparticles, tannery waste solution

Procedia PDF Downloads 373
9838 A Transfer Function Representation of Thermo-Acoustic Dynamics for Combustors

Authors: Myunggon Yoon, Jung-Ho Moon

Abstract:

In this paper, we present a transfer function representation of a general one-dimensional combustor. The input of the transfer function is a heat rate perturbation of a burner and the output is a flow velocity perturbation at the burner. This paper considers a general combustor model composed of multiple cans with different cross sectional areas, along with a non-zero flow rate.

Keywords: combustor, dynamics, thermoacoustics, transfer function

Procedia PDF Downloads 353
9837 The Algorithm to Solve the Extend General Malfatti’s Problem in a Convex Circular Triangle

Authors: Ching-Shoei Chiang

Abstract:

The Malfatti’s Problem solves the problem of fitting 3 circles into a right triangle such that these 3 circles are tangent to each other, and each circle is also tangent to a pair of the triangle’s sides. This problem has been extended to any triangle (called general Malfatti’s Problem). Furthermore, the problem has been extended to have 1+2+…+n circles inside the triangle with special tangency properties among circles and triangle sides; we call it extended general Malfatti’s problem. In the extended general Malfatti’s problem, call it Tri(Tn), where Tn is the triangle number, there are closed-form solutions for Tri(T₁) (inscribed circle) problem and Tri(T₂) (3 Malfatti’s circles) problem. These problems become more complex when n is greater than 2. In solving Tri(Tn) problem, n>2, algorithms have been proposed to solve these problems numerically. With a similar idea, this paper proposed an algorithm to find the radii of circles with the same tangency properties. Instead of the boundary of the triangle being a straight line, we use a convex circular arc as the boundary and try to find Tn circles inside this convex circular triangle with the same tangency properties among circles and boundary Carc. We call these problems the Carc(Tn) problems. The CPU time it takes for Carc(T16) problem, which finds 136 circles inside a convex circular triangle with specified tangency properties, is less than one second.

Keywords: circle packing, computer-aided geometric design, geometric constraint solver, Malfatti’s problem

Procedia PDF Downloads 70
9836 Ecotoxicity Evaluation Methodology for Metallurgical and Steel Wastes

Authors: G. Pelozo, N. Quaranta

Abstract:

The assessment of environmental hazard and ecotoxicological potential of industrial wastes has become an issue of concern in many countries. Therefore, the aim of this work is to develop a methodology, adapting an Argentinian standard, which allows analyze the ecotoxicological effect of various metallurgical and steel wastes. Foundry sand, white mud, red mud, electric arc furnace dust, converter slag, among others, are the studied wastes. The species used to analyze the ecotoxicological effects of wastes is rye grass (Lolium Perenne). The choice of this kind lies, among other things, in its easy and rapid germination making it possible to develop the test in a few days. Moreover, since the processes involved are general for most seeds, the obtained results with this kind are representative, in general, of the effects on seeds or seedlings. Since the studied residues are solids, prior to performing the assay, an eluate is obtained by stirring for 2 hours and subsequent filtration of a solution of waste in water in a relationship of 1:4. This represents 100% of eluate from which two dilutions in water (25% and 50%) are prepared. A sample with untreated solid waste and water is also performed. The test is performed by placing two filter papers in a Petri dish that are saturated with 3.5ml of the prepared dilutions. After that 20 rye grass seeds are placed, and the Petri dishes are covered and the seeds are incubated for 120 hours at 24 °C. Reference controls are carried out by distilled water. Three replicates are performed for each concentration. Once the exposure period is finished, inhibiting elongation of the root is measured (IR). The results of this test show that all the studied wastes produce an unfavorable effect on the development of the seedlings, being the electric arc furnace dust which more affects the germination.

Keywords: ecotoxicity, industrial wastes, environmental hazard, seeds

Procedia PDF Downloads 373