Experimental approach to mechanical properties of natural rubber mixing with Calcium carbonate powder
December 2012
Mechanical properties of natural rubber (NR) and calcium carbonate as additive filler with amounts of 5, 10, 15, 20, and 25 parts per hundred (pphr) were studied. The influence of calcium carbonate content on hardness and tensile strength of NR were investigated. The results were obtained from the tests shown. NR hardness and tensile strength was enhanced after adding calcium carbonate powder and...
Virtual power plant (VPP) and economic dispatch (ED)
December 2012
In this paper, general concept of a virtual power plant (VPP) and its model is developed. In the proposed model for the VPP, power system is divided into smaller subsystems, and it is called the power system cells. Each cell is a small network that has a control center and management system. The concept...
On regression analysis using modified bivariate ranked set sampling design (BVRSS)
December 2012
Research on several forms of ranked set samples had been done by many researchers recently for estimating the population mean and other parameters. The results have ascertained that the ranked set samples are proven to be more efficient than the simple random samples in many situations. In this paper, modified bivariate ranked set sample (MBVRSS) was introduced to estimate a simple linear regression model when the...
Translation surfaces according to Frenet frame in Minkowski 3-space
December 2012
In this paper, using non-planar space curves, the translation surfaces were investigated according to Frenet frames in Minkowski 3-space and some properties of these surfaces were given. Furthermore, we calculated first fundamental form, second fundamental form, Gaussian curvature and mean curvature of the translation surface. Also, the Darboux frame of the generator curves of the translation surfaces in Minkowski...
An efficient numerical integration algorithm for single-layer Raster cellular neural networks simulator
December 2012
An efficient numerical integration algorithm for single layer Raster cellular neural networks(CNN) simulator is presented in this paper. The simulator is capable of performing CNN simulations for any size of input image, thus a powerful tool for researchers investigating potential applications of CNN. This paper reports an efficient algorithm exploiting the latency properties of CNN along with numerical...
Effects of different impregnation chemicals on combustion characteristics and decay resistance of wood
December 2012
This study was aimed to determine combustion characteristics and decay resistance of Spruce [Picea orientalis (L.)], Fir (Abies nordmanniana), Alder [Alnus glutinosa (L.)], and Iroko (Milicia excelsa) woods impregnated with ammonium tetrafluoro borate (1 to 3%) and the mixture of cement and borax (6% to 9%). The combustion test method was performed in three stages: flame stage, without...
Dielectric properties of spray pyrolized Aluminum doped Cadmium sulfide (Al-doped CdS) thin films
December 2012
Spray pyrolysis has been applied to deposit of Cadmium sulfide (CdS) and Aluminium doped Cadmium sulfide (Al-doped CdS) thin films. These films were used in various devices such as solar cells, sensors, and solid oxide fuel cells. Optical and dielectric properties such as transmittance (T%), absorption coefficient (α), real dielectric constant (), imaginary dielectric constant (), and dielectric loss (δ)...
Experimental analysis of hydrophobic characteristics of Silicone rubber (SiR) insulators under different climatic conditions
December 2012
The electrical performance of polymeric insulators depends on the hydrophobicity of their surfaces. In this study, the contact and / or receding angle of a water droplet at the surface of Silicone rubber insulators is measured under different climatic conditions of Egypt. This paper experimentally investigates the effects of various environmental factors (e.g desert’s dust, cement and fertilizer) on the...
Numeric and experimental survey of a condenser to porous media of granite
November 2012
This article evaluates the numeric and experimental survey of a distiller's condenser for brackish water whose saltiness varies between 5 to 10 g/L. The condenser is a cylindrical tank, in which is vertically arranged and the pieces of granite constituent of porous media. The governing equations that describe the transfers are deduced from a thermal and mass global balance within the condenser. Finite difference...
Alternating current (AC) electroosmotic flow of generalized Maxwell fluids through a circular microtube
November 2012
An analytical solution for the time periodic electroosmotic flow (EOF) of the generalized Maxwell model through a circular microtube is presented by solving the linearized Poisson-Boltzmann equation, together with Cauchy momentum equation and General Maxwell constitutive equation. By numerical calculations, we find that for lower Ω and smaller De, classical plug-like profile of Newtonian fluids is reduced. At...
Transient magnetohydrodynamic (MHD) flow of a visco-elastic fluid past an infinite vertical porous plate embedded in a porous medium with Hall current and slip condition in a rotating system
November 2012
An attempt is made to present a theoretical analysis of a transient magnetohydrodynamic (MHD) flow of a visco-elastic fluid (Walter’s B’) past an infinite vertical porous plate embedded in a porous medium with constant permeability in a rotating system in the presence of Hall current when the plate temperature varies periodically with time. The expressions for the non-dimensional velocity field, temperature...
The Dirac equation with position-dependent mass for the modified Pöschl-Teller potential and its solution
November 2012
The Dirac-modified Pöschl-Teller problem with position dependent mass is investigated within the framework of the asymptotic iteration method in N dimensions. Any -state solutions are obtained by using the exponential approximation for the centrifugal term. The energy eigenvalues and two-component spinor corresponding eigenfunctions are determined for different screening...
Modeling and simulation of UPFC using PSCAD/EMTDC
November 2012
This paper proposes to model and simulate a unified power flow controller (UPFC) in power system computer aided design and electromagnetic transient direct current (PSCAD/EMTDC) environment. The series converter of the UPFC controls the transmission line real/reactive power flow and the shunt converter of the UPFC controls the UPFC bus voltage/shunt reactive power and the DC link capacitor voltage. The real power demand...
Teachers’ views about the application of secondary Physics course curriculum
November 2012
The main purpose of this study is to investigate teachers’ views about the application of secondary Physics curriculum (9, 10, and 11 grade) whose application had been started from 2008 to 2009 academic years and gradually extended to other grades. The study is a descriptive survey for determining the situation. In the study, a scanning model has been used. Sample of the study consists of 82 Physics teachers who...
Exact and explicit solutions for the discrete Burgers equation by means of the Exp-function method
November 2012
In recent years, various direct methods were proposed to find exact solutions not only for nonlinear partial differential equations but also for nonlinear differential-difference equations (NDDEs). In this paper, the Exp-function method was extended to the discrete Burgers equation for searching traveling waves in closed forms. It was shown that the equation supported discrete solitary wave solutions. Our results,...
The effect of mineral admixtures and micronized calcite on alkali silica reaction expansions in the usage of aggregates from different origin
November 2012
This paper investigates the effectiveness of two zeolites with different reactive silica content, fly ash (FA), blast furnace slag (BFC), silica fume (SF), and micronized calcite (MC) in reducing expansion of concrete due to alkali-silica reaction. Also in this research, effects of three different cement usages were investigated by using accelerated mortar bar method, ASTM C1260. Five different aggregates, three natural...
Coastal geoid improvement using airborne gravimetric data in the United Arab Emirates
November 2012
Military survey department (MSD) of The United Arab Emirates (UAE) has undertaken the Airborne Gravity Survey Project for the marine area of the country. The main purpose for the implementation of the airborne gravity survey for the marine area is to improve the existing gravimetric geoid of the UAE. The airborne gravity data was estimated to have accuracy better than 2.0 mGal. The first gravimetric geoid for the...
Tectonic framework of Lunayyir area, northwest Saudi Arabia through aftershock sequence analysis of 19 May, 2009 earthquake and aeromagnetic data
November 2012
Permanent and temporary seismic stations that were deployed at Lunayyir area before and shortly after the occurrence of the 19 May, 2009 earthquake swarm (Mw 5.7) have recorded a number great of events. The main objective is to determine the tectonic framework of the area and prepare more representative tectonic model for the area. Through the detailed analysis of aftershock sequence it is clarified that; 1) the...
Some oscillating motions of a Burgers' fluid
November 2012
In this work, the exact analytic solutions for some unsteady oscillating flows of an incompressible Burgers' fluid in a duct of rectangular cross-section are considered. Here, two types of flows, namely, (1) flow due to the oscillating pressure gradient, and (2) flow due to the oscillation of duct parallel to its length, were considered. The exact analytical expressions for the velocity field and the adequate shear...
A semi-empirical approach to the geometric progression (GP) fitting approximation in estimating photon buildup factor in soft tissue, water, and dosimetric materials
November 2012
Photon buildup factors for soft tissue, water, and dosimetric materials have been computed in the energy range of 0.2 to 2 MeV using geometric progression (GP) fitting approximation. The results for soft tissue and water have been compared with the values obtained through Monte Carlo code MCNP4C. Data obtained from GP fitting method quite well obey a semi empirical relation which is a function of penetration depth,...
Determination of mass attenuation coefficients for concretes containing tincal concentrator waste
November 2012
This study is concerned with the use of the concrete samples produced by tincal concentrator waste as a gamma radiation shield. The values of mass attenuation coefficients for concrete samples measured at 59.54 (Am-241) and 80.99 (Ba-133) keV photon energies. Gamma rays were counted by a NaI(Tl) detector coupled to multi channel analyzer (MCA) using narrow beam transmission arrangement. Theoretical values...
Chemical and mineral analyses of Mwea clays
November 2012
Raw clays from Mwea area, Kirinyaga County, in the Republic of Kenya have been analyzed for their major and minor chemical elements. The clays were analyzed after subjection to different heating temperatures, of between 100 and 550°C, cooling and washing them with mineral acids of different concentrations. The results of the study show that the major components of the raw clays, when expressed as the oxides are:...
Application of response surface methodology for electrochemical destruction of cyanide
November 2012
This study investigated the influence of experimental factors on the electrochemical cyanide destruction efficiency in a flow-through reactor using response surface methodology. Central composite experimental design was used to obtain the four main operating factors, such as current density, initial cyanide concentration, chloride concentration, and electrolysis time, on the response surface of cyanide destruction...
Bayesian analysis of two parameter Pareto mixture using censoring
November 2012
The Pareto distribution is a commonly used model for heavy tailed data. Pareto distribution is a useful modeling and predicting tool in a wide variety of socioeconomic contexts. In the present study, we model heterogeneous population by using two component mixture model and two parameter Pareto mixture is considered for this purpose. The expressions for Bayes estimators and their posterior risks (using squared error...
The algorithm of Fuzzy C-Means clustering based on non-negative matrix factorization
November 2012
Clustering analysis is an effective method to discover and identify tumor classes. So, this paper proposes a Fuzzy C-Means clustering (FCM) algorithm based on Non-negative matrix factorization (NMF). Firstly, gene expression profiling (GEP) is simply processed through mean and variance of gene expression, which can then be mapped into a low dimensional space by NMF method. Finally, for discovering and identifying cancer...
On-line drill wear monitoring in high speed machining of jute fiber-reinforced composites using virtual instrumentation
November 2012
Many challenges in machining need to be overcome in replacing fiber reinforced composites. In this work, jute fiber reinforced bioepoxy resin laminates were manufactured, drilled and inspected. The drilling operations were performed on jute fiber reinforced composites by high speed steel (HSS) drill bits. Drill wear state prediction allows the determination of the hole quality as well as tool replacement...
Development of the sugarcane harvester using a small engine in Northeast Thailand
November 2012
This research presents the developing sugarcane harvester using small engine in order to focus on its appropriateness in sugarcane farming for farmers who are encountering problems of labor shortage and sugar factories lacking sugar cane for producing sugar. It is operated by 180 hp (134.28 kW) at 2500 rpm. Sugarcane was harvested at 12 months after planting with an average-stalk length of 1.8 m, and average-stalk...
Theoretical background of 1/f fluctuations of energy partition among harmonic oscillators in equilibrium
November 2012
A physical background is derived for the generation of 1/f fluctuations that are observed ubiquitously in energy partition in quasi-harmonic oscillators that exchange energy through weak nonlinear interactions. Weak three-mode coupling terms in the unperturbed Hamiltonian bring no net transfer of energy between oscillators, but four-mode coupling terms bring about irreversible energy transfer between unperturbed...
Chebyshev-Tau method for the linear Klein-Gordon equation
November 2012
In this paper, we study a numerical method based on polynomial approximation, using the shifted Chebyshev polynomial, to construct the approximate solutions of the one dimensional linear Klein-Gordon equation with constant coefficients. Also, we give general forms of the operational matrices of integral and derivative. We solve two illustrative examples to test this method known as the shifted Chebyshev Tau method. By...
Solution of sixth-order boundary-value problems by collocation method using Haar wavelets
November 2012
A new method based on uniform Haar wavelets is proposed for the numerical solution of sixth-order two-point boundary value problems (BVPs) in ordinary differential equations. Numerical examples are given to illustrate the practical usefulness of present approach. Accuracy and efficiency of the suggested method is established through comparison with the existing spline based technique and variational iteration method....
Experimental investigations of immune fuzzy Q-learning algorithms for robot obstacle avoidance
November 2012
This article presents a new approach to car-like robot control for obstacle avoidance and target tracking. The proposed approach employs cooperative algorithms including artificial immune algorithms, fuzzy logic and Q-learning denoted shortly as IFQ-learning control. The article explains the artificial immune system and the proposed algorithms. The fuzzy Q-learning algorithms are also presented. The article elaborates...
Effect of storage and thermochemical treatments on glass indentation cracks and residual stresses
November 2012
In this work, the effect of storage, annealing and chemical strengthening on indentation radial cracks of a sodalime glass is presented. During the storage of an indented glass with a Vickers indenter, the induced radial cracks propagate under the combined effect of the residual stresses and the environmental humidity (stress corrosion). The cracks length achieves a threshold of stability after 6 to 24 h. The...
Influence of natural long fiber in mechanical, thermal and recycling properties of thermoplastic composites in automotive components
November 2012
Natural fiber thermoplastic components in the automotive industry can afford the advantages of weight, cost reduction and recyclability, compared to conventional materials. Handlings of natural fibers in automotive exterior and interior components are essential to recover eco-efficiency and renewability. Natural fibers have recently become affordable to automotive industry as an alternative reinforcement for glass fiber...
Low temperature hydrothermal synthesis of BaTiO3 with ultra-high crystallinity
November 2012
Nano-sized barium titanate (BaTiO3) powders with ultra-high crystallinity have been successfully prepared by a hydrothermal condition at 170°C for only 2 h. In this study, the influence of processing parameters on the phase and the particle size of hydrothermally derived BaTiO3 powders was investigated. The powders were investigated by X-ray diffraction (XRD), scanning election microscopy (SEM),...
Development of an experimental apparatus for testing a total knee prostheses focused on Mexican phenotype
November 2012
This work was focused on the design and development of an experimental loading rig adapted to make experimental tests of total knee prosthesis. Location of contact points due to rotation and translation of simultaneous movements was analyzed carefully. This takes place between the femoral component and the polyethylene insert, since this is one of the main obstacles in the design of devices adapted to...
Determinants of residential water demand in an arid and oil rich country: A case study of Riyadh city in Saudi Arabia
November 2012
The accurate forecast of residential water demand is critically important for arid and oil rich countries such as Saudi Arabia which depend on costly desalination plants to satisfy the growing water demand. Achieving the desired prediction accuracy is a challenging task since the forecast model should take into consideration a variety of factors such as economic development, climate conditions and population growth. The...
River Usuma: A medium of assessing bioavailability of heavy metals in Abuja
November 2012
River Usuma was used as a substrate through which toxic elements and their sources were identified and measured due to anthropogenic activities in Federal Capital Territory (FCT), Abuja. It makes good public health sense, good economic and environmental sense to prevent water contamination at the source. Concentrations of heavy metals [Zinc (Zn), Manganese (Mn), Copper (Cu), Cadmium (Cd), Lead (Pb), Iron (Fe),...
Interaction of essential properties of potential layers in stormwater management using column method
November 2012
Yearly forecasting data indicate that wet season occurs at short intervals. Flooding and drainage problems have been sources of complaints from local and surrounding communities in Sri Gading area. The current situation is made more difficult because of the flat area and low infiltration rate. An investigation on this location shows that most of the Parit Raja area sits on compacted clay more than 30 m deep. The failure...
Sample of Batman in determination of urban solid waste management and recycling potential
November 2012
The collection, transport, treatment, and disposal of solid wastes, particularly wastes generated in medium and large urban centres, have become a relatively difficult problem to solve for those responsible for their management. However, recycling-related activities bring waste reduction, prevention of waste of raw materials and less environmental damage as well as providing an economic benefit to the countries. In this...
Composition dependence of structural, morphological and magnetic properties of Co (FCC)-Cu granular films
November 2012
The Cobalt (Co) (FCC)-Copper (Cu) magnetic films with different compositions (x = 55.5, 44.4, 22.5) grown on glass substrate are prepared by sputtering process using a Co target and Cu sheets. The effects of the composition on morphological, structural and magnetic of the films were reported. Scanning electron microscopy (SEM) results showed that the film thickness is about 80 nm. Atomic force microscopy (AFM)...
Application of Benjamin-Feir equations to Tornadoes’ rogue waves modulational instability in oceans
November 2012
Pilots put their plane in the ideal conditions for the atmosphere to suck it and allow a successful launch; similarly some portions of the ocean surface put a Troposphere column placed above them in ideal temperature and humidity training tornadoes and primary gravity waves that accompany them. To study the behavior of rogue waves triggered by tornadoes in terms of their space and time evolution, that is, their motion...
Breast tumor detection using microwave ultra wideband (UWB) forward scattering radar system
November 2012
Most of the currently established techniques for breast cancer have inherent disadvantages, such as destructive effects, image accuracy, and others. In addition, mammography and nuclear methods have a potential for producing harmful ionization effects in humans. Another technique for breast cancer detection is microwave imaging radar, which has the advantage of a less hazardous modality and is a non-destructive method....
Individual and competitive adsorption of Lead(II) and Nickel(II) ions by chemically activated carbons
November 2012
This work deals with the removal of heavy metals from wastewater which presents a major ecological problem. Recently, this has been solved by using adsorption techniques as a means to extract heavy metal ions. The present investigation was carried out on the adsorption of heavy metals from single and binary component aqueous solutions on activated carbons. The concentrations of heavy metals ions, Ni(II) and Pb(II),...
Analysis and optimization of a repairable M[x]/G/1 queue with an additional optional vacation
November 2012
This paper investigates an M[x]/G/1 queueing system with an unreliable server, where the server may take an additional vacation after the essential vacation. If the system becomes empty, the server leaves the system and takes the essential vacation. At the end of the essential vacation, the server may return to the system with probability p or take another vacation with probability 1-p. When the additional...
Metallic phytoremediation and extraction of nanoparticles
November 2012
The use of phytoremediation is a non-destructive method of heavy metal’s removal from soils. Water hyacinth plant (Eichhronia crassipes), normally found in habitats around the world, and has the ability to extract heavy metals through its roots, stem, and leaves. The main aims of this study were two folds; the use of water hyacinth plant to remove metals (Lead, Pb; Copper, Cu; Zinc, Zn; Chromium, Cr; and Cadmium,...
Returning to the old belief of "ether" is mandatory
November 2012
Luminiferous ether or light-bearing ether or simply ”ether”, which had been mentioned somehow since 17th century by Boyle, once believed to be a medium for traveling of light. Although, experiments like the Michelson and Morley could not prove its existence. In this article, we try to explain that, the experiments for detecting ether should be done in ultra-high velocities (over 5000 km/s), and that;...
Hardness-improvement of titanium using mixture gases
November 2012
Hardness of 99.7% titanium was improved in acetylene-ammonia mixtures at 1,250°C for 2 h. The flow rate of acetylene was set constantly at 0.4 cm3s-1, but those of ammonia were varied over the range of 0 to 12 cm3s-1. By using an X-ray diffractometer (XRD) and an energy dispersive X-ray (EDX) analyzer, TiC, TiN, TiC0.7N0.3, and TiC0.3N0.7 phases with the corresponding elements were detected. Knoop hardness...
Compositional domain dynamics in two-coupled lipid monolayer: A mean field approximation approach
November 2012
A continuum model for artificial membrane was developed by treating the upper and lower layers of the membrane as a pair of coupled Ising monolayers. Linear coupling between the layers was included. Linear stability analysis was used to predict the phase diagram. The dependence of the phase-separated regions on inter-layer coupling is determined. We numerically solve the Cahn-Hilliard type equations to obtain domain...
Wind energy conversion system with full-scale power converter and squirrel cage induction generator
November 2012
This paper describes a modeling and control of a variable speed squirrel-cage induction generator with back to back power electronics converters used in variable speed wind energy conversion system. The power electronics is composed of the generator side converter (GSC) coupling to the grid connected converter (GCC) together via DC bus capacitor. The generator side converter (GSC) is controlled by direct torque...
A life cycle assessment of a coal fired power plant with carbon capture and storage in Mexico
October 2012
A life cycle assessment (LCA) was conducted for three cases with the goal of assessing the environmental viability of carbon capture and storage (CCS) as a method of reducing greenhouse gas emissions from the electricity infrastructure in Mexico. Case 1 is standard coal fired power plant, 350 MW and 35.7% efficiency. Case 2 is the same power plant with facilities for carbon dioxide capture using absorption by...
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