November 2011
A review of glass-ceramics production from silicate wastes
Glass-ceramics are produced by crystallization of glass. It is also produced using waste materials, and particularly silicate based wastes such as: coal ash, slag, fly-ash and waste from incinerators. The production of glass-ceramics from these wastes using different methods is considered in this paper. The properties of the product are also considered; this review focused on silicate wastes into useful...
November 2011
Arsenic contamination of groundwater in Bangladesh: A review
The groundwater arsenic contamination in Bangladesh is known as the largest natural calamity in the world in terms of the affected population. The millions of tube-wells that had been sunk for drinking water supply are now dispensing poisonous arsenic. Consequently, about 80 million people are at risk and another 30 million are potentially exposed to arsenic poisoning. Most of the recognized stages of arsenic...
November 2011
The impact of the variability of ionospheric phase refractive index on radio signals instability
The ionospheric phase refractive index is a complex function that determines the attenuation and the trajectory of radio signals through the ionosphere. This complex refractive index model has been obtained using the Maxwell's equations, the tensorial conductivity equation, electron collision models, and the geomagnetic field model. The model has been used to study and investigate the phase refractive...
November 2011
Stress-strain modelling of reinforced concrete membrane structures
In this study, a nonlinear finite element (FE) model is proposed to investigate the behaviour and failure mechanism of reinforced concrete membrane structures. Proven accurate stress-strain relation is incorporated in the model to describe the stress-strain behaviour of the concrete under compression for uniaxial and biaxial stress system. The nonlinearity behaviour of the materials in the compressive stress...
November 2011
Maximum power point tracking of variable speed wind energy conversion system
This paper proposes a simple method to maximum power control of wind turbine and induction generator connected with two back to back voltage source converters to grid. Machine currents are controlled by indirect vector control method. In this method, generator side converter controls the maximum excitation (air gap flux) by machine's d-axis current and controls generator torque by machine's q-axis...
November 2011
Comparison of two synchronization methods for fractional order double scroll chaotic system
Synchronization of fractional-order chaotic system has received considerable attention for many research activities in recent years. In this Letter, we introduced a double scroll of fractional-order chaotic system. For the purpose of synchronization, we consider the driven response method and the one-way coupling method. Both the theoretical proof and numerical simulations show the effectiveness of the two...
November 2011
Analytical evaluation of the nonlinear vibration of a solid circular sector object
This paper applied a new class of critical technique for resolution of the cyclic solutions nonlinear called the HE’s variational approach method (VAM) to solve the nonlinear vibration of a solid circular sector object. In variational approach, only one repetition leads to high exactness of the solutions, as opposed to the other methods. It has been found that the variational approach is very prolific,...
November 2011
Wind speed forecasting based on autoregressive moving average- exponential generalized autoregressive conditional heteroscedasticity-generalized error distribution (ARMA-EGARCH-GED) model
With the increase of wind power as a renewable energy source in many countries, wind speed forecasting has become more and more important to the planning of wind speed plants, the scheduling of dispatchable generation and tariffs in the day-ahead electricity market, and the operation of power systems. However, the uncertainty of wind speed makes troubles in them. For this reason, a wind speed forecasting...
November 2011
Spar platform at deep water region in Malaysian sea
Exploration of oil and gas resources has been accelerated towards deeper waters due to depletion of their reserve in shallow water depth. Malaysian sedimentary basins signpost the existence of these energy sources below its sea-bed. In deep sea depth, traditional fixed types of offshore structures to explore these resources have become incongruous and they have resorted to new configurations. Spar platform is...
November 2011
Design optimization of an active vibration isolation system
Several engineering systems require isolation of sensitive equipment from foundation vibrations or isolation of the foundation from machinery vibrations. Even though passive vibration isolation systems are effective in reducing the amplification at resonance, high frequencies attenuation is poor. Active vibration isolation (AVI) systems are being used for eliminating this problem. AVI is essential in multiple...
November 2011
A new measurement method of separation percentage for human blood plasma based on ultrasound attenuation
In this research, the separation accuracy of blood-plasma-based multi-decay pulse-power technique (MDPPT) was presented. The MDPPT provides adjustable-path measurements according to the amplitude of transmitted pulses and accurate attenuation measurements of propagation echoes through blood and blood plasma; thus, reduction of time and power consumption during the plasma separation process was achieved using...
November 2011
Monte Carlo and density functional theory (DFT) investigation of boron-nitride nano cones in different solvents
Quantum Monte Carlo (QMC), molecular dynamics (MD) simulations and density functional theory (DFT) calculations at the level of B3LYP/3-21G was carried out on the structure and stability of B10N11H7 (Thr)2 in bulk and different solvent medium. NMR parameters and thermodynamic properties were calculated to obtain chemical shift, stability and solvent effect. It was found that...
November 2011
A general method for finding the exact solution of linear Volterra integral equations of the second kind
In this paper, a general method is given for the solution of linear Volterra integral equations of the second kind, which is based on the action of the operator defined by the kernel of the integral equation on a suitable basis for the corresponding function spaces. The necessary conditions for using this method are so weak that extends its applicability. The solved examples show the strength of this...
November 2011
Reliable approach of iterative method for nonlinear fractional differential equations
In this paper, a new approach of the iterative method is developed to handle nonlinear differential equations of fractional order. For this reason, an efficient modification of iterative method, namely iterative-Laurent method, is introduced based on iterative method and Laurent series expansion. The proposed approach is capable of reducing the size of calculations and easily overcome the difficulty arising...
November 2011
Process queuing in the automobile manufacturing body shop: Using a multi-objective model
The automobile industry is one of the most important industries in global economics. The automobile manufacturing industry consists of many shops and many stations. Each station has a number of operations, which depend on the number of welded pieces in those stations. One of these shops is the body shop. The problems that occur in the body shop concern queuing and the lead time between stations. This paper...
November 2011
Dependability of congregated next generation network architecture
The next generation network is a future based network providing next generation services such as internet protocol television (IPTV), online gaming, video on demand etc, based on IP protocol in the presence of core network. This research based paper discusses the architecture of next generation network (NGN), challenges, solutions, reliability, pros and cons. The main objective is to investigate...
November 2011
Simulation analysis of 2.4 GHz MEMS/NEMS voltage controlled oscillator
This paper presents the design and analysis of a novel 2.4 GHz Voltage Controlled Oscillator (VCO), with amplitude control and Q enhancement circuit, for wireless communication applications. The variable capacitors and the inductors were designed using ANSYS and imported through DAC components in ADS (Advanced Design software). Accurate simulation of the VCO was performed in the software environments and the...
November 2011
Linear quadratic optimal control system design using particle swarm optimization algorithm
Selecting appropriate weighting matrices for desired linear quadratic regulator (LQR) controller design using evolutionary algorithms is presented in this paper. Obviously, it is not easy to determine the appropriate weighting matrices for an optimal control system and a suitable systematic method is not presented for this goal. In other words, there is no direct relationship between weighting matrices and...
November 2011
Three-dimensional visualisation of coastal geomorphology using fuzzy B-spline of dinsar technique
This paper introduces a new approach for mapping coastal geomorphology by using differential synthetic aperture radar interferometry (DInSAR). Fuzzy B-spline is used to accelerate and improve the accuracy of 3-D map from DInSAR. The DInSAR algorithm involved two parts: 3-D map simulation and interferogram simulation with discrete element method (DEM) and satellite orbit parameters. 3-D coastal...
November 2011
Grid resources selection optimization with quality of service guarantee by a hybrid algorithm of genetic and particle swarm optimization
When a large number of tasks request different resources in a grid system, resources allocation should have been done with proper planning and scheduling to guarantee a good quality of service (QOS). There are different ways to provide these requests by choosing appropriate resources allocation to optimize the total operation of the system. In this study, first some parameters, such as priority, delay,...
November 2011
An efficient Markov model for reliability analysis of predictive hybrid m-out-of-n systems
In this paper, predictive hybrid redundancy has been extended to large-scale control systems comprising n modules. In m-out-of-n systems, if m-out-of-n modules are in agreement, the system can report consensus; otherwise the system fails. While in our new extension, if there is no agreement, a history record of previous successful result(s) is used to predict the output. In order to analyze the reliability of...
November 2011
An object-oriented approach of generic diffusion computing for three dimensional ultrasound volumetric images
Medical image information representation using two dimensional image planes have major drawbacks on the grounds that the there are technical constrains in providing the optimized spatial orientation and physical limitations. In comparison, three dimensional imaging shows higher degree of versatility in clinical application. Conventional anisotropic diffusion and speckle removal might have promising...
November 2011
Persian handwritten digits recognition: A divide and conquer approach based on mixture of MLP experts
In pursuit of Persian handwritten digit recognition, many machine learning techniques have been utilized. Mixture of experts (MOE) is one of the most popular and interesting combining methods which has great potential to improve performance in machine learning. In MOE, during a competitive learning process, the gating networks supervise dividing input space between experts and experts obtain specialization on...
November 2011
Enhanced oxygen gas sensor by surface-etched gallium oxide
Surface-etched Pt/gallium oxide semiconductor structure has been successfully fabricated and studied for the sensing of oxygen gas. The effects of the sandwich oxide structure with larger sensing area on the oxygen gas sensing property are investigated. In the existence of the etched V-groove gallium oxide geometry, its electrical and sensing properties, that is, high sensitivity, significant increase in...
November 2011
Metal spraying for revamping and keeping pieces
Metal spraying for coating industrial pieces and products are applied in different industrial fields. In these recent years, many researchers have focused on developing various metal spraying methods and their relevant conditions and characteristics. Metal spaying are applied for revamping and reforming new and worn out pieces. In the surface coating by metal spraying, metal particles shoots to the considered...
November 2011
Optimization of input process parameters variation on threshold voltage in 45 nm NMOS device
In this study, Taguchi method was used to optimize the influence of process parameter variations on threshold voltage (VTH) in 45 nm n-channel metal oxide semiconductor (NMOS) device. The orthogonal array, the signal-to-noise ratio, and analysis of variance were employed to study the performance characteristics of a device. In this paper, eleven process parameters (control factors) were varied for 2 levels to...
November 2011
Water heights and weather regimes at Alexandria Harbor
The response of water level variations to the changes in local meteorological elements (atmospheric pressure, air temperature and wind force) has been investigated for Alexandria harbor over 11 years period (1995 to 2005). The study has shown clearly a close connection between them. The coherence is noted and the linear effect is discussed. The result of the regression technique indicated an increase of water...
November 2011
Diffusion coefficient of ions in migration through soil liners
Contaminant transport through soil liners with low hydraulic conductivity is both by advection and diffusion processes though the diffusion process is dominate. Diffusion coefficient of migrating species has to be considered to calculate the velocity of contaminant flume. Diffusion through a network of clay particles is slower and porous media diffusion coefficient (Dp) is used to consider tortuous flow...
November 2011
Geomorphometric analysis on the some riverbeds in the Romanian plain
The present study refers to some hydrographic basins in the Romanian Plain and appeals to morphometric methods based on the Horton Strahler river hierarchy system. The central part of the Romanian Plain located between ArgeÅŸ (East), Olt (West), Cotmeana Piedmont (North) and Danube (South) has a highly dense hydrographic network. The Vedea and Neajlov basins (for which the major source of the trunk river is...
November 2011
A research on work accidents in forest products industry in Duzce
This study aimed at examining the work accidents and their possible causes experienced by the workers of the industry of forest products active in Duzce and their occupationallives, and determining the solutions suggested. In this study, a questionnaire method was used as a data gathering tool. The questionnaire used in the study composed of 4 main parts and 46 questions. In the forest...
November 2011
Effects of annealing parameters on grain-growth behavior of HAYNES®-718 superalloy
Annealing heat-treatment experiments at temperatures in the range of 1050 to 1150°C (1323 to 1423K) for durations in the range of 20 min to 22 h were conducted for HAYNESÒ718 superalloy plate. Grain sizes for the as-received and the annealed samples of the superalloy were measured by application of quantitative metallographic techniques. The grain-growth exponents, n, for the kinetic...
November 2011
Recursive parameter estimation for discrete-time model of an electro-hydraulic servo system with varying forgetting factor
In general, an electro-hydraulic servo (EHS) system inherently suffers from parameter uncertainties and variation which makes the modeling and controller design complicated. To encounter those difficulties, recursive least square (RLS) is often used with advanced control strategy for position, force and pressure control of the EHS system. In this paper, a new RLS estimator with varying forgetting factor was...
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