June 2013
Performance evaluation of wireless multipath/shadowed G-distributed channel
In wireless communication the effect of multipath as well as shadowing takes place simultaneously over the channel and this phenomena leads to composite fading. G-distribution is frequently encountered distribution in wireless fading environment. Combination of multipath fading and shadowing model are used as composite fading model. This composite fading model is named as G-distribution. G-distribution...
June 2013
Educational software for radial power system protection
This paper presents a set of analysis tools for self learning for radial power system protection training (Bouhenna 2010). It automates a radial feeder for an overcurrent protection that would include fault calculations, fuse-fuse co-ordination, current transformer, relay-relay and fuse-relay co-ordination, directional overcurrent protection, ground fault protection, automatic recloser and sectionalizer. The...
June 2013
Formulation and characterization of self compacting concrete with silica fume
Self-compacting concrete (SCC) was elaborated using local materials and silica fume (SF) as admixture in 15% of cement quantity, two different Portland cements (PC) and two different superplasticizer that the chemical nature is polycarboxylate and plynaphtalene, the aggregates used are (AG 3/8 mm, AG 8/15 mm), coarse and fine sand (SC, SF) witch fineness modulus 3.2 and 1 in the order. The dosage of...
May 2013
Implementation of neural network for monitoring and prediction of surface roughness in a virtual end milling process of a CNC vertical milling machine
This paper presents a real time simulation for virtual end milling process. Alyuda NeuroIntelligence was used to design and implement an artificial neural network. Artificial neural networks (ANN’s) is an approach to evolve an efficient model for estimation of surface roughness, based on a set of input cutting conditions. Neural network algorithms are developed for use as a direct modeling method, to...
May 2013
Effects of viscosity on phase separation of liquid mixtures with a critical point of miscibility
After quenching a high-viscosity partially miscible critical liquid mixture to a temperature far below the critical point, we observed the formation of rapidly coalescing droplets, whose size grew linearly with time, indicating that phase separation process is driven byconvection. As predicted by the diffuse interface...
May 2013
Potential research of carbon (iv) oxide enhanced oil recovery (CO2-EOR) in Middle East
Anthropological carbon (iv) oxide (CO2) emissions to the atmosphere are identified as amajor driver for the global warming effect. Major CO2 emissions sources are locatedwithin power and industrial sectors where fossil fuels are consumed to generate...
March 2013
Bubble dynamics and interface phenomenon
The dispersion of gas into liquid is a complex part and it is depending on bubble size and its distribution including coalescence and breakup. The study of flow pattern, bubble size and its distribution and factors affecting the bubble size was reviewed by several authors. Various measurement techniques of bubble size are also reported in literature. In this paper we have made an attempt to show the...
March 2013
Modelling some ergonomic parameters with machine parameter using hand powered maize sheller
The economic situation in most developing countries have left farmers and processors operating at the small scale, hence the use of automated and electric power driven equipment is limited to the few large scale processors. The effect of the ergonomic parameters namely; weight, age, height and arm length in relation to the resulting efficiencies; shelling efficiency, cleaning efficiency, mechanical damage and...
March 2013
Development of a realtime microcomputer-based logging system for diagnosis and research
In this research, a realtime temperature logging system that logs human temperature into the computer over a period was developed and the temperature chart produced is useful for diagnosis and research purposes. The graphical representation within the threshold temperature (36°C) depicts normal body temperature of a healthy person. An upshot beyond this temperature makes the logger to signal an audible...
February 2013
An evolutionary programming embedded Tabu search method for hydro-thermal scheduling with cooling – banking constraints
This paper presents a new approach for solving the unit commitment problem (UCP) in hydro-thermal power system. The main objective of this paper is to find the generation scheduling by committing the generating units such that the total operating cost can be minimized by satisfying both the forecasted load demand and various operating constraints. It is a Global optimization technique for solving UCP,...
February 2013
Design and simulation study of a simple ion injector
The stated purpose of this manuscript is to study the parameters of a single-gap accelerator system with a view to optimizing the transport of a beam of argon ions. A study is made for the main factors that must be considered on the design of an ion injector taking into account the appropriate design of the single gap accelerator column by doing such study both analytically and with ion beam simulation. These...
January 2013
Application of chemical injection on cooling treatment technology control of corrosion and fouling in petrochemical plant: Case study of Indorama Plc, Akpajo-Eleme
Corrosion and fouling has been a major menace to the operation, integrity and life expectancy of process equipment in the production line of refinery and petrochemical equipment. This research focuses on effective cooling water treatment technology by inhibitive and bio-remediative chemical injection to control fouling and minimizes corrosion in process equipment such as boiler, heat exchangers and heaters...
January 2013
Design and construction of fish smoking kiln
The design and construction of fish smoking kiln was undertaken with the aim of improving the existing fish smoking kiln. The kiln consists of metal frame made of angle iron on which the entire component was assembled. The handle controls the speed of the ventilation fan through chain and sprocket. The charcoal housing is made of perforated metal sheet to allow for proper ventilation. The kiln is operated...
December 2012
Trend in ground water fluctuation in Gidan Kwano Inland Valley of Niger State Nigeria
Trend in ground water table fluctuation was investigated on an experimental field of 18070.2 m2 between June and March of a following year. Five Piezometers were used to monitor the depth of water table at different locations. Findings indicated a depth of water table fluctuation between 0.4 cm above the soil surface and 200 cm below surface. Further analysis carried out on possible relationship between...
December 2012
Sodium chloride concentration on the rheological and dynamic properties of aloe vera gel
Aloe vera gel is a highly medicinal gel which is in high demand in the cosmetics and pharmaceutical industry. Mathematical models were developed to simulate the rheological and dynamic properties of aloe vera gel in relation to the addition of sodium chloride (NaCl – common salt) at various concentrations. The result from the investigation shows the effect of sodium chloride concentration on the...
December 2012
Improving Web Content Management System: Template personalization approach
Web Content Management System (WCMS) has been developed to facilitate different aspects of website development. However, up until now, designing of web pages is accomplished by the website developers. Even though WCMS might suggest a number of templates, but it does not consider the nature of the website that will be developed. Many designers have complained about designing the right structure, and different...
November 2012
Brain fingerprinting
Brain finger printing is based on finding that the brain generates a unique brain wave pattern when a person encounters a familiar stimulus. Use of functional magnetic resonance imaging in lie detection derives from studies suggesting that persons asked to lie show different patterns of brain activity than they do when being truthful. Issues related to the use of such evidence in courts are discussed. In the...
November 2012
Dielectric relaxation, electrical conductivity and impedance response of Barium titanate (BT) and Strontium titanate (ST) doped Ba(Fe0.5Nb0.5)O3 ceramics
Lead-free polycrystalline ceramics of Ba(Fe0.5Nb0.5)O3 and its solid solutions 0.91Ba(Fe0.5Nb0.5)O3-0.09BaTiO3 (BFN-BT) and 0.91Ba(Fe0.5Nb0.5)O3-0.09SrTiO3 (BFN-ST) were fabricated by a solid-state reaction process, and their electrical properties were characterized in a broad frequency range (100 Hz to 1 MHz) at a temperature range from 30 to 385°C. The prepared ceramics are single...
November 2012
Experimental determination of damping ratios at higher modes for use in modal superposition
While carrying out the transient analysis, the major challenge is to provide accurate damping ratio data for higher modes as this is not reported. Hence an attempt is made to find out the damping ratios experimentally in this paper. Two approaches of experimental evaluation of damping ratios are discussed, for free and forced vibration, with four different materials namely: mild steel, aluminum, cast iron and...
October 2012
Using structured analysis for the control of real-time systems
After a presentation of the real time system analysis and design, we present the Structured Analysis for Real Time Systems, or SA-RT. This graphical design notation is focusing on analyzing the functional behaviour and information flow through a system. In fact, the modeling of the real time systems helps us to understand its working, without eliminating its complexity. Then, we present the graphic and textual formalism...
October 2012
Numerical study of heat transfer in pulsating turbulent air flow
A numerical investigation of heat transfer characteristics of pulsating turbulent flow in a circular tube is carried out. The flow is thermally and hydrodynamically fully developed and the tube wall is subjected to a uniform heat flux. The flow inlet to the pipe consists of fixed component and pulsating component that varies sinusoidally with time. The flow and temperature fields are computed numerically...
April 2012
Heat flux and plasma parameters in plasma welding by means of velocity shear instability
Industrial applications of plasma welding technology are in spot light in many industries. The flexibility of coupling electric field, magnetic field and parameters in plasma heat flux has been demonstrated in selected pilot scale and plasma welding for metallurgical and parametallurgical purpose. This paper present effect of different parameters: magnetic field, homogenous Direct Current electric field (DC),...
April 2012
Sliding mode application in speed control of an induction machine coupled in a hydraulic system
In this paper, a nonlinear control of an induction motor (IM) supplied with a photovoltaic generator to assure the level control of two coupled tanks is designed. The global system is decomposed into two separate models thus, coupled are assured by discontinuous command. In the first step, we propose a sliding mode technique to make the speed and the flux control of the IM robust to parameter variations....
February 2012
An optimal parametric design to improve pool boiling heat transfer of sintered surfaces
This study investigated the effect of design parameters on pool boiling heat transfer on the sintered surfaces of a tube. The pool boiling experiments were conducted in saturated, deionized and degassed water. Data were taken at an atmospherical pressure and a fixed heat flux of 41,000.In the experimentation, the effects of the sintering pressure, sintering time, sintering temperature, heating rate, and...
February 2012
Liquid crystal-reconfigurable conformal monopole antennas structures for microwave applications
In this article, the design of conformal monopole antennas on a very thin layer of flexible liquid crystals (LCs) is introduced. The flexible LC substrate can be bent and folded over the module case, resulting in a tight integration of the antenna with the frontend module. Firstly, a meander monopole antenna, designed for single band operation, is presented with details of the structure, simulation and...
February 2012
Recent advances of distributed optical fiber Raman amplifiers in ultra wide wavelength division multiplexing telecommunication networks
Recently, many research works have been focused on the fiber optic devices for optical communication systems. One of the main interests is on the optical amplifiers to boost a weak signal in the communication systems. In order to overcome the limitations imposed by electrical regeneration, a means of optical amplification was sought. The competing technology emerged: the first was Raman amplification. One...
February 2012
Investigation into the kinetics of biodegradation of crude oil in different soils
An experimental study was conducted to examine crude oil degradation in different soil (clay, sandy loamy and swampy soil) of 1, 2, 3, 4 and 5 ml × 10 kg-1 pollution. The polluted crude oil and soil samples were obtained from Niger Delta area of Nigeria and microbial analysis were conducted on the samples for the purpose of identification, isolation and characterization of possible microbes with a...
January 2012
High speed performance of semiconductor electrooptic modulators for multi Gigahertz communication systems operation
The effects of electrodes geometry and temperature on high frequency radio frequency transmission characteristics are deeply investigated against semiconductor material based electro optic modulator devices such as aluminum gallium arsenide (AlGaAs) and optical waveguide parameters. On the other hand, we have developed the optimization of the electro-optic modulator parameters where the effective index plays...
January 2012
Digital very-large-scale integration (VLSI) Hopfield neural network implementation on field programmable gate arrays (FPGA) for solving constraint satisfaction problems
This paper discusses the implementation of Hopfield neural networks for solving constraint satisfaction problems using field programmable gate arrays (FPGAs). It discusses techniques for formulating such problems as discrete neural networks, and then it describes the N-Queen problem using this formulation. Finally results will be presented which compare the computation times for the custom computer against...
December 2011
Facial feature units’ localization using horizontal information of most significant bit planes
We present here an approach to find the exact position of some feature units related to human face images. We use the horizontal information in most significant bit planes of images to accomplish the task. Finding location of facial feature units is of importance as most human face recognition approaches take it as initial point. The prominent feature units in a face are eyes, nostrils and lips which are...
December 2011
N and P resorption efficiency and proficiency from leaves under different forest management systems of deciduous woody species
Leaf N and P resorption efficiency and proficiency were explored in three permanent (non–tiled) and unfertilised plots: a Castanea sativa mill. paraclimax coppice (CC), a chestnut orchard (CO), and Quercus pyrenaica Wild. climax forest (Oak), adjacent to the CO plot, all located in central western Spain. To estimate the seasonal variation of the nutrients contained in the leaves, 9,...
December 2011
Social aspects of engineering
This article discusses the relationships and linkages between the extended engineering profession and other intangible facets of human society. While describing how basic human needs, which engineers were used to satisfy, had transformed in the 21st century into a milieu of almost unlimited desires, the author emphasizes the new challenges engineering faces today. One of outcomes resulting from this change of...
December 2011
The effect of mesophilic and thermophilic temperature on bonny light crude oil degradation in Niger Delta Area of Nigeria using Pseudomonas sp.
In this study the effect of mesophilic and thermophilic temperature on Bonny light crude oil degradation was tested on the freshwater and salt water media. To this end the pH, optical density, refractor index, specific gravity, density, microbial population and viscosity were determined using experiment analysis. Experiments were performed using environmentally relevant concentrations of the test substances...
December 2011
Modeling the rate of biocorrosion and the effects of redox-reactions of metals in water environment
Laboratory studies were conducted to assess the effectiveness of biocorrosion through oxygen diffusion in zinc metal in water environment. The present investigation was undertaken to determine the corrosion rate of zinc metal in water environment with respect to Plank-Nernst Equation modified to monitor and predict the biocorrosion rate through oxygen diffusion which resulted to biofilm formation. The...
November 2011
A novel electrical model to an antenna array
In this paper, an electrical model is developed to represent the input admittance of an antenna array with a finite number of elements. This model consists of an RLC bock component to represent the input admittance of each elementary antenna element and a capacity component to represent different degrees of antenna coupling effects. The equations based on cavity model are developed to represent physical...
November 2011
Electromyographic (EMG) signal to joint torque processing and effect of various factors on EMG to torque model
This study present electromyographic (EMG) signal to torque model and investigates the effects of various factors on EMG signal and EMG to torque model. Pre-processing techniques are applied on EMG signal in order to remove the DC offset, 60 Hz noise and to estimate the EMG amplitude. The estimated EMG amplitude is then mapped to joint torque using a new non-linear equation. This equation uses some...
November 2011
Performance evaluation of bamboo with morter and concrete
Bamboo has remarkable properties as a construction material, being both light weight and extremely strength and durable. Moreover it grows all over the Bangladesh; a South Asian lower-middle income country where rural people is the majority of the total population. Bamboo having considerable tensile and compressive strength as a construction material is used widely in Bangladesh. But the main problem that it...
October 2011
Influence of finishing temperature on the mechanical properties of conventional hot rolled steel bar
The conventional mill operators are faced with challenges of producing reinforcing steel bars of adequate strength characteristics. This stems from the inability to effectively control and monitor process variables such as temperature, strain-rate and cooling. These parameters collectively determine the microstructure and invariably the mechanical properties of the rolled bars. However, the finishing...
October 2011
An investigation of the effect of hall current and rotational parameter on dissipative fluid flow past a vertical semi-infinite plate
Magneto hydrodynamics (MHD) stokes problem for a vertical semi-infinite plate in a dissipative rotating fluid with hall current has been considered. The partial differential equations governing the problem are framed and then solved using numerical methods of implicit finite difference approximations. An analysis of effects of parameter on the velocity (both primary and secondary) profiles and...
September 2011
Stochastic redundancy allocation problem using simulation
Reliability is one of the main parameters of the products considered to be important to survive in the competitive market. Reliability in its simple form means the probability that a failure may not occur in a given period of time that is, the component performs adequately without failure. The subsystems or components in a system are arranged in series or parallel depending on the space constraint. However,...
September 2011
Electrochemical properties of metals in cassava fluid
This study was carried out to investigate and evaluate the electrochemical properties of mild steel (0.6, 1.0 and 1.46 mm), galvanized steel (0.36, 0.6 and 1.24 mm) and aluminium (0.9 and 1.3 mm) sheets exposed to cassava fluid. Corrosion rates of mild steel (10.595 mm/yr), galvanized steel (11.26 mm/yr) and aluminium (9.556 mm/yr) sheets exposed to cassava fluid were got using weight loss technique. The...
September 2011
Ultra low loss of a thermal arrayed waveguide grating (AWG) module in passive optical networks
In the present paper, high transmission bit rate of a thermal arrayed waveguide grating (AWG) which is composed of lithium niobate (LiNbO3)/polymethyl metha acrylate (PMMA) hybrid materials on a silicon substrate in passive optical networks (PONs) has parametrically analyzed and investigated over wide range of the affecting parameters. We have theoretically investigated the temperature dependent wavelength...
September 2011
Effect of rapid quenching and aging on tensile behavior of commercially pure (CP) titanium implant material
Pure titanium and titanium alloys are widely used as implant materials in the medical and dental fields because of their superior bio-compatibility, corrosion resistance and specific strength compared with other metallic implant materials. Study of mechanical properties of these implant materials is very important during the course of their machining, fabrication and surface treatment...
September 2011
Modeling the distribution of primes in computable biomolecules
Prime numbers are an important research area with application in computer security. The security of certain cryptographic schemes critical in information security lies in the difficulty of factoring large numbers into their prime factors. Determination of the distribution of prime numbers is an important unsolved problem in number theory. Biomolecules such as DNA have extended the domains of what is...
August 2011
Electrical characterization of in-house fabricated polysilicon micro-gap for yeast concentration measurement
Fabrication and electrical characterization of micro-gaps and their properties are discussed with their applications in electrochemical sensors and bimolecular detection. To understand the relationship between the biosensor and micro-structure we have carried out the fabrication and characterization of micro-gap structures for yeast concentration measurement. In this paper two photo mask designs are used. The first mask...
August 2011
Effect of geopathic stress zone on human body voltage and skin resistance
Geopathic stress zones are places on the surface of the Earth known to cause health problem. Empirical knowledge of the existence of geopathic stress is probably as old as mankind. The aim of this study is to evaluate the effect of geopathic stress on human body. It further tries to scientifically evaluate dowsing phenomenon by measuring body voltage, skin resistance, using V-20 bio voltmeter, GSR-2 biofeedback...
August 2011
Atomic force microscopy (AFM) and X-ray diffraction (XRD) studies of BiFeO3 nanoparticles with sol–gel
Recently, there has been considerable interest in studying nanostructural properties of Bismuth (Bi) as a good electrode of electro-analysis, shape–memory alloys and photo-typical multiferric devices. We have thus demonstrated a series of experiments to synthesis Bi and BiFeO3 (BFO) nanoparticles using sol–gel method at ambient pressure and study their nanostructural properties using tapping mode of...
August 2011
Smart crack detection of a cracked cantilever beam using fuzzy logic technology with hybrid membership functions
Damage detection methods have been considerably increased over the past few decades. A crack in a structural member introduces local flexibility that would affect vibration response of the structure. This property may be used to detect existence of a crack together with its location and depth in the structural member. The presence of damage leads to changes in some of the lower natural frequencies and mode...
July 2011
Low temperature synthesis of La2O3 and CrO2 by Sol–gel process
Some issues such as tunneling, leakage current and light atom penetration through the film are threatening the ultra thin SiO2 be as a good dielectric for future industrial and electronic devices and in ceramic technologies. A series of experiments to synthesis La2O3 as well as CrO2 has been done at low temperature with using sol-gel method. The nano structural properties of La2O3/CrO2 equipped with...
July 2011
Two-dimensional particle modeling of submicrometer ZnO MESFET based on an ensemble Monte Carlo calculation including five-valley band structure model
A Monte Carlo method has been developed for the study of electron transport properties in ZnO MESFET for high field, using a five-valley conduction band model. The effects of upper valleys on the characteristics of ZnO MESFETs have been investigated. The following scattering mechanisms, that is impurity, polar optical phonon, acoustic phonon, alloy and piezoelectric are included in the calculation. Ionized impurity...
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