Synthesis and characterization of Nickel hydroxide/ oxide nanoparticles by the complexation-precipitation method
March 2011
In the present research work, the synthesis of Ni (OH)2 and NiO nanoparticles with narrow size distribution and uniform shape, by complexation-precipitation method using ammonia as complexing agent, was investigated. The reactions were carried out at the temperature about 70°C in the solution and the precipitated nickel hydroxide precursor, in the form of the nanosized soft agglomerates, was calcined...
Synthesis and characterization of dehydroannulene carbon allotrope apply for hydrogen fuel storage
March 2011
Recent developments focusing on novel hydrogen storage media have helped to focus nano materials as one of the on going strategic research in science and technology. In particular, carbon nano materials and specifically dehydroannulene carbon stand to deliver unparalleled performance as the next generation of base materials for storing hydrogen. The very low boiling point of H2 makes it necessary to...
Effects of different water, phosphorus and magnesium doses on the quality and yield factors of soybean (Glycine max L.) in Harran plain conditions
March 2011
This study reports the effects of magnesium (Mg) and phosphorus (P) fertilizer dosage and different water levels, on the plant growth, yield and quality factors of soybean. The field study used a random block design with three replications and was conducted over two years, 2006 and 2007. Four different P doses (0-4-8-12 kg P da-1) and three different Mg doses (0-4-8 kg Mg da-1) were applied with...
Synthesis of various nano and micro ZnSe morphologies by using hydrothermal method
March 2011
In this contribution, hydrothermal method was used to synthesize ZnSe nanostructures. Effect of different sources of Zn, Se and cetyl tri-methyl-ammonium bromide (CTAB) (cationic) surfactant on the morphology of ZnSe was studied. The prepared nanostructures were characterized using powder X-ray diffraction (XRD) and emission scanning electron microscopy (SEM). The XRD patterns showed that the ZnSe samples...
Bactericidal activity of various brands of cephradine against Staphylococcus aureus
March 2011
A retrospective eight-year study (January 1998 to December 1999 and January 2008 to December 2009) was under taken in a Government Hospital in Islamabad, Pakistan to evaluate bactericidal activity of various brands of cephradine against Staphylococcus aureus. The maximum resistance of the bacterium was observed for ampicillin, penicillin and cotrimaxazole. Where as, the minimum resistance was...
A new approach of the radial basis functions method for telegraph equations
March 2011
This paper represents a new approach of the radial basis functions method for handling a class of the second-order hyperbolic telegraph equation. In this approach, we decompose the domain of the problem to a few sub domains as vertically or horizontally. The proposed approach is capable of reducing the size of calculations and easily overcomes the difficulty of solving complicated algebraic systems...
Solutions of nonlinear singular initial value problems by modified homotopy perturbation method
March 2011
In this paper we present an efficient modification of the homotopy perturbation method. We apply the method to solve a class of singular initial value problems (IVPs) in the second-order ordinary differential equations (ODEs). Modified homotopy perturbation method (MHPM) yields solutions in convergent series forms with easily computable terms, and in some cases, yields exact solutions in one iteration....
Solution of the nonlinear PDAEs by variational iteration method and its applications in nanoelectronics
March 2011
In this paper, the system of nonlinear partial differential-algebraic equations is solved by the well-known variational iteration method and the results with high accuracy are obtained by only one iteration. Furthermore, some nanoelectronics models are expressed by partial differential-algebraic equations and one of them is successfully solved by the proposed method. Although solving nonlinear PDAEs is...
Effects of thermal radiation and magnetic field on unsteady mixed convection flow and heat transfer over a porous stretching surface in the presence of internal heat generation/absorption
March 2011
The problem of magneto-hydrodynamic unsteady mixed convective flow and heat transfer of an electrically conducting fluid over a porous stretching surface in the presence of heat generation/absorption and thermal radiation has been investigated. It is assumed that the unsteadiness is caused by the impulsive motion of the free stream velocity and by sudden increase in the surface temperature. The...
Some results about log-harmonic mappings
March 2011
Let A(α, β) be a subclass of certain analytic functions and H (D) is to be a linear space of all analytic functions defined on the open unit disc D = {z| |z| < 1}. A sense-preserving log-harmonic function is the solution of the non-linear elliptic partial differential equation; where w(z) is analytic, satisfies the condition ...
Radiation effect on chemically reacting magnetohydrodynamics (MHD) boundary layer flow of heat and mass transfer through a porous vertical flat plate
March 2011
A mathematical model is presented for a two-dimensional, steady, viscous, incompressible, electrically conducting and laminar free convection boundary layer flow with radiation from a flat plate in a chemically reactive medium in the presence of a transverse magnetic field. The basic equations governing the flow are in the form of partial differential equations and have been reduced to a set of non-linear ordinary...
A robust traffic quantity measurement with video surveillance
March 2011
Video and image processing have been used for traffic supervision, analysis and monitoring of traffic condition in many cities and urban areas. The system described in this paper aims to approach the precise method to obtain the traffic flow, time headway and traffic volume through a sequence of images captured with a stationary video camera. The method consists of three algorithms. First, background modeling and...
Application of artificial neural networks to predict compressive strength of high strength concrete
March 2011
A method to predict 28-day compressive strength of high strength concrete (HSC) by using MFNNs is proposed in this paper. The artificial neural networks (ANN) model is constructed trained and tested using the available data. A total of 368 different data of HSC mix-designs were collected from technical literature. The data used to predict the compressive strength with ANN consisted of...
A passivity criterion for fixed-point state-space digital filters
March 2011
This paper proposes a new criterion for passivity of fixed-point state-space digital filters with saturation arithmetic and external interference. The criterion guarantees not only exponentially stability, but also passivity from the external interference to the output vector. The criterion takes the form of linear matrix inequality (LMI) and, hence, is computationally tractable. An illustrative example is...
A novel robust two-stage extended Kalman filter for bearings-only maneuvering target tracking
March 2011
A novel robust filter is proposed via embedding extended Kalman filter into an optimal two-stage Kalman filter, which is improved through a modified Sage-Husa noise statistics estimator. Meanwhile, strong tracking multiple fading factors are introduced in this paper to improve the tracking performance for high maneuvering targets. The new method provides an optimal estimation of the target state through a...
A block orthogonal matching pursuit algorithm based on sensing dictionary
March 2011
A block version of the orthogonal matching pursuit (OMP) algorithm, termed BOMP, can yield better reconstruction performance for block-sparse signals than conventional algorithms. However, the redundant dictionaries for block sparse signals are block coherent in the particle applications. In this paper, we consider a modified version of BOMP by introducing the concept of sensing dictionary. Exploiting the...
Investigation of dosimetry in human head model for a helical antenna with mobile phone
March 2011
This paper proposes a dosimetric analysis in realistic human head model for a helical antenna with phone model. The finite-difference time-domain (FDTD) method with lossy-Drude model is adopted in this study. The technique of SAR measurement is addressed and then the effects of head model size on SAR characteristics for a cellular phone exposure at 835 MHz respectively. The head model, was developed from...
Dynamic resource allocation in mobile WiMAX using particle swarm optimization techniques
March 2011
Allocating radio resources dynamically in wireless network is highly complex and non-linear. It becomes even more complex when the wireless network is designed for heterogeneous traffics with different quality of service (QoS) requirement like WiMAX network. In this paper, we proposed a low complex algorithm for subcarrier allocation in multiuser OFDM of WiMAX system. The proposed algorithm uses particle...
Production of landslide susceptibility map of Samsun (Turkey) City Center by using frequency ratio method
March 2011
Due to the increased need for housing, Samsun province center had been quickly opened for construction in the last 25 years; because of the rapid population growth, construction facilities have progressed towards the southern hillside of the city. Large amount of landslides had been observed and classified in this region by the relevant institutions. To prevent life and property losses, it is required to...
Geoinformatics for characterizing and understanding the spatio-temporal dynamics (1969 to 2008) of Hokersar wetland in Kashmir Himalayas
March 2011
In the present study, the Hokersar wetland, in Kashmir Himalayas, that is abode to millions of migratory birds, has been chosen to assess the changes in the land use/land cover and areal extent of the wetland during the last four decades. Topographic maps of 1969 and the remote sensing data for 1992, 2001, 2005 and 2008 was used for determining the spatio-temporal dynamics of the...
Temperature effect on fish culture tank facilities inside greenhouse
March 2011
This study was performed to evaluate the effect of tank position on the water temperature of fish culture tanks in aquaculture facilities inside a greenhouse. The temperature was measured in four 20- m3 capacity tanks. Three points were measured for each tank: point A, the water in the fish culture tanks; point B, the environment outside of the tanks and point C, a point 0.3 m below the soil level. The measurements were...
Heavy metals contamination of soil and groundwater at automobile mechanic villages in Ibadan, Nigeria
March 2011
The aim was to determine the concentrations of heavy metals, in soil and groundwater at automobile mechanic villages located in Ibadan, Nigeria, compare the results with guidelines from various countries, draw conclusions and make recommendations. Soil and groundwater samples from 7 automobile mechanic villages and a control site in Ibadan, Nigeria were analysed for selected heavy metals namely: Cd, Cu, Pb,...
Efficacy of solar water disinfection for well waters: Case study of Ibadan slums, Nigeria
March 2011
The study was carried out to assess the efficacy of solar radiation as a disinfection method for well waters in some communities in the south east local government area of Ibadan metropolis, Nigeria. Well water sampling and quality tests were done during the dry season and parameters such as total solids, suspended solids, total hardness and coli form count were...
Economical analysis of trigeneration system
March 2011
Trigeneration systems should be designed to supply all energy demands of a new facility and increase the profit of an existing facility. In this paper, a model to determine optimum capacity of trigeneration systems that maximizes the present value of the net profit hasbeen developed to embed trigeneration systems to existing systems. Proposed economical model has been employed on a university campus....
Determination and optimization of the effect of cutting parameters and workpiece length on the geometric tolerances and surface roughness in turning operation
March 2011
In this work, the geometric tolerance and surface quality of an aluminium piece produced by turning is analysed. The effect of the length and diameter of working piece, cutting depth and feed were also investigated. The cutting speed, which is an important machining parameter, was kept constant in this study. Going from past works experience the effect of cutting speed was ignored. Statically method of...
Detailed analysis of consumption of the transport device by the mobile device
March 2011
This paper deals with the gathering of GPS data and other personal information that iares used to calculate the consumption of motor vehicles. To create a basic test application for the measurement consumption (Microsoft Visual Studio, 2008), C # programming language was used. The application is designed for devices based on Windows Mobile. For testing, a few PDA devices with integrated GPS module were used. The...
Three phase inverter control using DSP controller for dynamic voltage restorer (DVR) application
March 2011
This paper discusses the control technique improvement of a three-phase inverter using direct-quadrature-zero (d-q-0) controller based on DSP TMS320F2812 for dynamic voltage restorer (DVR) applications. The output of the inverter is then connected to a voltage grid via a second order filter and injection transformer. The control algorithms are developed using TMS320F 2812 DSP. The proposed technique achieves...
First principle study of the effect of Co substitution on the magnetic and electronic properties of wz-ZnO
March 2011
We have studied the electronic and magnetic properties of Zn0.75Co0.25O compound. The calculations were done by SIESTA and WIEN2K code based on the density functional theory (DFT). We have used a Pseudopotential (PsP) and full potential (FP) approaches in our calculations, as implemented in SIESTA and WIEN2K code respectively. The generalized gradient approximation (GGA) was used for exchange-correlation...
A novel wide-band dual function fiber amplifier
March 2011
The design of a novel wideband Dual-function Erbium-doped fiber amplifier (EDFA) with chirped fiber Bragg grating (CFBG) configured in two-stage double pass amplification scheme is demonstrated in this paper. The proposed architecture is designed to increase amplification bandwidth. The purpose of utilizing the CFBG is to reflect the amplified signal back to the Erbium-doped fiber and to compensate...
Foundation of vortex gravitation, cosmology and cosmogony
March 2011
A hypothesis is proposed concerning the cause of the origin of universal gravitation. This cause consists in a system of the ether vortex rotations. Physical and mathematical grounds are described and the formula for the determination of the space gravitation forces was deduced. On the basis of the vortex gravitation, the principles of creation and existence of the celestial bodies were shown. Methods of the...
Double-gate tunnel FET with silicon nitride and oxynitride
March 2011
A. Bahari1*, F. Pourzaman2 and M. Hoseni2
Geoelectric investigation of treasured formation strata and groundwater potential in Ogume, Delta State, Nigeria
March 2011
Ogume in Delta State is a town of great geophysical interest because its formation strata are entirely different from those of the neighbouring towns and communities. It has formations of high economic and structural importance hence, it is now known as the “treasure land” of Delta state. It is therefore important that a geophysical study be made in Ogume to ascertain its formation...
Evaluation of geomorphosites in Vistea Valley (Fagaras Mountains-Carpathians, Romania)
March 2011
This paper aims at evaluation of geomorphosites on the Vistea Valley (the Fagaras Mountains). The Fagaras Mountains are emblematic for the Romanian Carpathians as they have the highest altitudes (2544 m), the biggest massiveness and a large range of geomorphosites which were formed by the action of the glaciers. The Vistea Valley is a typical glacial valley, being part of the glaciers complex with the same name. The...
Geophysical analysis of the soils for civil (Geotechnical) engineering and urban planning purposes: Some case histories from Turkey
March 2011
The aim of this study is to review the geophysical investigations in civil engineering and urban planning by some case histories in Turkey. Geophysics deals with a wide array of earth phenomena, including the temperature distribution of the earth's interior (the source, configuration and variations of the geomagnetic field) and the large-scale features of the terrestrial crust, such as rifts, continental...
New formulation of a forgotten old variational principle
March 2011
An old variational principle (Maupertuis principle), forgotten as inconvenient quirk of history, has been reformulated into the modified variational principle (MVP) along with its reciprocal principle (RMP) and both these principles have been derived classically as well as quantum mechanically. Wide scope of applicability of these new principles in classical mechanics has been demonstrated by solving...
Differential transform method for nonlinear fractional gas dynamics equation
March 2011
In the present study, an analytic solution of nonlinear fractional gas dynamics equation was deduced with the help of the powerful differential transform method (DTM). To illustrate the ability and efficiency of the method, two special cases of the equation has been solved Key words: Differential transform method, nonlinear fractional gas dynamics equation.
Differential transform method for systems of Volterra integral equations of the second kind and comparison with homotopy perturbation method
March 2011
In this article, differential transform method was employed to solve Volterra integral equations of the second kind. The procedure of the method is illustrated systematically. In this paper some results useful have been proved for the first time, and they have been used in the solution of these systems. To show the power of this method, some examples have been created (Examples 2 and 3) and solved. The...
Addressing a critical success factor for software projects: A multi-round Delphi study of TSP
March 2011
A five-round Delphi study was conducted to determine the degree to which the Team Software Process (TSP) can address the identified critical success factors for software projects. Three high-reputation and high-calibre experts participated in this study. Our results found agreement among the experts that the TSP provided the ‘Best Practises’ for addressing 14 critical success factors. The experts...
Pupil tracking method based on particle filtering in gaze tracking system
March 2011
In this paper we proposed a pupil tracking method based on particle filtering in active infrared source gaze tracking system. We constructed a pupil target model with the combination of gray characteristic and shape characteristic so that the target and the background can be distinguished easily. Pupil motion model which can predict pupil location and shape feature in the next frame was built. Gray histogram...
Improvement of gas turbine performance based on inlet air cooling systems: A technical review
February 2011
Performance of a gas turbine is mainly depends on the inlet air temperature. The power output of a gas turbine depends on the flow of mass through it. This is precisely the reason why on hot days, when air is less dense, power output falls off. A rise of 1°C temperature of inlet air decreases the power output by 1%. The aim of this paper is to review up to date techniques that were developed to cool...
Spatial analysis of a post-socialist city: Case of Tirana-Albania
February 2011
This study proposes an analysis model to see how urban spatial configuration in case of post-socialist Tirana City transformed over time. The analysis of city network road and comercial facilities distribution of Tirana City helps us to examine urban land use variation and the urban spatial structure. The study also reviews urban spatial structure model of the city as well. The main principles of space...
Synthesis and characterization of gold nanoparticles using 1-alkyl, 3-methyl imidazolium based ionic liquids
February 2011
The formation of gold nanoparticles has been studied via the reduction of the metal salts in different Ionic Liquids (Ils) based on the 1-alkyl-3-methyl-imidazolium cation and different anions. Particles were grown at different temperatures for 24 h. The structure and morphology of the resulting nanomaterials has been studied via wide angle x-ray scattering (WAXS), transmission electron microscopy (TEM),...
Use of K-means clustering in migraine detection by using EEG records under flash stimulation
February 2011
In this study, a new migraine analysis method was proposed by using EEG (electroencephalography) signals under flash stimulation in time domain. EEG signal is one of the most complex biomedical signals due to its complex nature. Therefore, these types of signals are commonly pre-processed before the analysis procedure. Since, pre-processing techniques affect the analysis results positively or negatively, the...
A bounded random process model and its application in heart rate variability analysis
February 2011
A bounded random process (BRP) model was developed in this paper to interpret why approximate entropy (ApEn) can not describe the stochastic characteristic of Brownian motion time series correctly. Low ApEn value, generally implying presence of determinacy, also existed in Brownian motion series, a stochastic process. The BRP model investigated this phenomenon through quantifying the relationship between ApEn...
A microstrip metamaterial split ring resonator
February 2011
This paper introduces a new low cost, robust microstrip structure, exhibiting metamaterial property, as a replacement of conventional bulky metamaterials structures. These types of planar microstrip structures are very useful for applications where space of equipment is a constraint. Although, the structure is inspired by Split-Ring resonator (SRR), it does not incorporate additional metallic rod for...
Enhancement of real-time multi-patient monitoring system based on wireless sensor networks
February 2011
Portable patient monitoring device has become increasingly important in Hospital wards to record real-time data during normal activity for better treatment. However, the current quality and reliability have not been satisfactory due to the size, weight, distance of coverage and also high power consumption. This paper provides several solutions for enhancing the reliability and improving the power management...
Equations of unsteady flow in curved trapezoidal channels
February 2011
Investigation of unsteady flows in curved channels and solving the related equations are one of the main issues in hydraulics. In this study, the numerical model proposed by ‘beam and warming’ using the finite difference method is presented to solve unsteady flow equations in curved-trapezoidal channels and it has been used by taking advantage of modified Model (regarding some...
Effects of different irrigation regimes and nitrogenous fertilizer on yield and growth parameters of maize
February 2011
A field experiment was carried out to find out the response on yield and yield contributing parameters of maize (cv. Bornali) to water stress and nitrogenous fertilizer. The experiment included two factors such as five irrigation regimes and four nitrogen levels. Texturally, the soil was silty loam. Yield and yield contributing characters were significantly affected due to the application of irrigation and...
Effect of crumb rubber concentration on the physical and rheological properties of rubberised bitumen binders
February 2011
The increase use of crumb rubber in flexible pavements requires the better understanding of its effect on physical and rheological properties of rubberised bitumen binders. The performance properties of rubberised bitumen binder are influenced by the blending conditions and crumb rubber content. The main objective of this research is to investigate the effect of various crumb rubber content on the physical,...
Use of the simplex method to optimize analytical condition in structural analysis
February 2011
The nonlinear behavior is approximated as a sequence of successively changing linear systems over a short time interval. Solution of nonlinear equations needs to iterative method such as Iterative algorithm. Iterative method attempts to solve a problem by finding successive approximations. The present study is concerned with methods of nonlinear static and dynamic analysis of structures,...
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