Doppler fading communication channel performance simulation
April 2017
Fading is commonly used to describe the properties of the communication channel. Large efforts have been made to describe characteristics of the channel in wireless communication system. The performance of wireless signal propagation in a conventional environment needs Doppler fading channel schemes by assuming a perfect knowledge about the channel frequency response at both the transmitter and the receiver sides. Two...
Application of data mining in telecommunication industry
March 2017
This paper applied a data mining model in sales and marketing department of Telecommunication Industry (TI) in Nigeria. The motivation behind the paper is as a result of competitive challenges facing most TI sales and marketing departments globally such as inability in gaining precise view of targeted data, inability to translate and formulate business question correctly and Problem of addressing data quality. The...
Pressure and temperature effects on corona onset voltage in electrostatic precipitators
March 2017
Corona onset voltage is one of the most important factors that determine the charging toxic particle in an industrial application. Electrostatic precipitators (ESP) remove the suspended particle with a gas inlet. This paper developed Peek's formula to estimate the maximum electric field near the discharge wire in corona discharge models, the values of maximum electric field and corona onset voltage near the...
Hydrogeochemical investigation and characterization of shallow groundwater within Ankpa Town, North Central Nigeria
March 2017
Physico-chemical analysis of groundwater samples from Ankpa, north central Nigeria was carried out to investigate the quality of the water for drinking and irrigation purposes. The results revealed water of average low pH, indicating slightly acidic conditions of the water. The water is soft, and it is characterized as Na++K - HCO3 type. It is good for drinking and other domestic uses. Four indices were evaluated from...
Performance evaluation of law enforcement agency on crime information management using queuing network model
February 2017
One of the greatest challenges facing every society today is crime control and management. It could be as little as pick–pocketing, or human trafficking, or even as deadly as terrorism. As criminal’s perfect ways of avoiding being detected, Law Enforcement Agencies (LEAs) must adopt innovative ways on crime prevention and control. This research applies Queuing Network (QN) model to evaluation the performance...
Effect of Co component in Co-Ag granular thin films on visible-light reflection applied by magnetic field
February 2017
The reflection of visible light (wavelength from 350 to 800 nm) on magnetic granular thin films Cox-Ag1-x with x from 0 to 35 at % was studied. Dependence of reflection (R) is strong on magnetic and percentage of Co in the thin films, R strongly increase in wavelengths 560 and 660 nm. In this paper, some arguments relating to the spin-plasmon phenomenon were used to explain the results. Key words: Granular magnetic...
Partial and total mass attenuation coefficients, effective atomic number and effective electron number of different Maraging steel compositions
January 2017
The total and partial mass attenuation coefficients for different Maraging steel compositions have been determined by using the WinXCom and MCNP5 programs. The effective atomic number, Zeff, and effective electron number, Neff, for the studied steels have been determined via the total mass attenuation coefficients μ/ρ, the total atomic and electronic cross sections (σa and σe) of the investigated...
Multiples in Onshore Niger Delta from 3D prestack seismic data
January 2017
The presence of multiples has been investigated in Onshore Niger Delta using 3D seismic data. The aim of the study was to investigate the characteristics of reflection events beyond 3s two way time on seismic data behind the boundary faults associated with the shadow zone. This involves detailed velocity analysis on semblance plot panel and accounting for moveouts due to reflections away and within the shadow...
Energy saving by applying the fuzzy cognitive map control in controlling the temperature and humidity of room
January 2017
This paper investigated the implementing of soft computing methodology of fuzzy cognitive map on controlling parameters of heating, ventilating and air-conditioning systems. In the past few years, many researches have been done on application of different controllers on heating, ventilating and air-conditioning system as a more energy consuming part of the building automation system. Unlike the conventional control...
Calibration and estimation of efficiency of Geiger Muller counter using a standard radioactive source
January 2017
The beta counting system uses a Geiger-Muller (GM) tube to detect the presence of beta contamination present in filter paper samples or in planchet samples. The counting system is enabled with a provision to count the samples at various distances from the detector to the sample position. The efficiency of the counting system is provided by the manufacturer at the time of procurement which is calibrated and...
Sandwich panels from cork and polyester in presence of epoxy resin as interfacial adhesive
December 2016
This work presents an experimental study to determine the mechanical properties in bending, tension, compression and shear of a new sandwich material based on natural materials (jute and cork). The sandwich material is made basically of natural materials whose soul is agglomerated cork white (located in Jijel, East of Algeria) and the skins are woven jute with ortho phthalic polyester resin. Agglomerated white cork...
Numerical modeling and determination of parameters characteristic of a photovoltaic module LRAER (FST Nouakchott)
December 2016
The main objective of this work is to study, develop and establish an approach through the mathematical model of performance CENERG under the term (MC). This model is used to characterize the parameters of photovoltaic systems in the literature. For this, we have considered the required performance is normally measured in standard test conditions (STC), where an average solar spectrum AM 1.5 is used, sunshine is...
Phasors from the linear algebra perspective applied to RLC circuits
December 2016
Phasors provide a simple way to analyze sinusoidally excited linear circuits. Solutions of those circuits would be undoable otherwise. Besides, measurement units in phasors are a technological resource that powers with precision the observation of the electric power system dynamic state. In the last technological research in electronics, through this units tension phasors and current phasors are obtained in a...
Thermo-economic study of hybrid cooling tower systems
November 2016
In this paper, the effects of ambient temperature and relative humidity on performance of wet, dry, and two combined cooling systems are studied for a typical 250 MW power plant in Hamedan, Iran. Although there have been many works in background of effects of different parameters on performance of cooling towers, there is no detail analysis about different alternatives of hybrid cooling systems due to the water...
Some fish species in offshore Fukushima, Japan have the ability to accumulate a specific nuclide (radioisotope)
November 2016
The Tokyo Electric Power Company's, Fukushima Dai-ichi nuclear power plant in Fukushima-Ken (Fukushima Prefecture), Japan, was destroyed in March 2011 by a massive magnitude 9 earthquake (centred offshore to the northeast of Honshu Island) and by the subsequent historic Tsunami of March 11, 2011. Because of the nuclear meltdown, hydrogen-explosion damage to the buildings that housed the reactors, and the...
Troubled roads: Application of surface geophysics to highway failures of the sedimentary terrain (Iruekpen-Ifon Road) of Edo State, Nigeria
November 2016
As part of effort to examine the factors responsible for highway failure in the sedimentary terrain, geophysical survey involving Very Low Frequency Electromagnetic (VLF-EM), Schlumberger Vertical Electrical Sounding (VES), and dipole-dipole electrical resistivity techniques were carried out along Iruekpen-Ifon highway. This was aimed at using surface geophysics to characterize and identify the factors responsible the...
Baryte mineral exploration in parts of the lower Benue Trough, Nigeria
November 2016
The use of DC electrical method in baryte mineral exploration has been investigated in Buruku northeast of Markurdi, Nigeria. The objective of the study was to investigate the suitability and potential of electrical resistivity tomography (ERT) combined with vertical electrical sounding (VES) surveys in baryte mineral exploration over known deposits. Results show that the interpreted layer resistivities correlate with...
Investigation of self-association, optical transition probability and hetero-association with chlorogenic acid of nicotinamide using UV-Vis spectroscopy
November 2016
The self-association, optical transition probabilities, and hetero-association with chlorogenic acid of nicotinamide were obtained from UV-Vis spectroscopy in aqueous solution at room temperature (293K). The dimerization constant of nicotinamide ( ) was obtained using dimer model by nonlinear curve fitting technique. The hetero-association constant in the system of molecules of nicotinamide with chlorogenic acid...
First principles study of the relative stability and electronic properties of the VN/GaN/VN interlayer
October 2016
Using first principles total-energy calculations within the framework of density functional theory, the relative stability and the structural and electronic properties of a VN/GaN/VN interlayer in sodium chloride (NaCl), cesium chloride (CsCl), nickel arsenide (NiAs), zinc-blende, and wurtzite structures were studied. The calculations were carried out using a method based on pseudopotential, employed exactly as...
Particle model of single bubble sonoluminescence
October 2016
The single bubble sonoluminescence is a phenomenon where the vapour or gas bubble trapped in a liquid collapse by emitting light. Sonoluminescence is most often characterized by the formation of an imploding shock and the plasma. However, studies show that in some cases neither an imploding shock nor a plasma has been observed. This study concerns a physical explanation of the Single Bubble Sonoluminescence (SBSL),...
Natural radioactivity level of clay, ceramic, and stone cooking dishes in Saudi Arabia
September 2016
Standards and guidelines are needed in the manufacture of household cooking dishes from clay, ceramic, and stone in Saudi Arabia. The radioactivity levels due to the presence of 40K, 232Th, and 226Ra in these materials were determined using gamma spectrometry equipped with high purity germanium (HPGe) detector. The activity concentrations of 226Ra ranged from 5.75 Bq kg−1 (Yemen stone sample) to 192.35 Bq...
Electrical resistivity and Seebeck coefficient of Pd81Ge19
September 2016
We report on the simultaneous measurement of resistivity and Seebeck coefficients in samples of Pd81Ge19 ribbons prepared by the melt spinning technique method and having a typical dimension of 40.0 mm × 1.75 mm × 0.028 mm. The investigation was performed using a new completely automated device in a large temperature range (from room to 700°C). Structural changes, crystallization times and heat...
Development of a real time blood pressure, temperature measurement and reporting system for inpatients
September 2016
In this work, a real time blood pressure, temperature measurement and reporting system for inpatients was developed. The function of this system is to constantly measure the blood pressure and temperature of a patient and send the measured values to the medical doctor or other relevant care givers through wireless link. The system is built around the STM32F103C8 Microcontroller programmed in C language which performs...
Characterisation of mortars from the Ottoman period in Algiers (Algeria) through their physical and chemical properties
September 2016
In traditional and historical Algerian architecture, one can find a series of mortars that were used for grouting and coating masonry. Although Algeria has a very rich heritage park, our interest mainly focuses on the mortars used in buildings from the Ottoman period, in Algiers and in particular, the mortars of the Citadel of Algiers, the Casbah and villa Mahieddine. This study allows us to determine the physical...
Mineral determination and radiological risk caused by geological formations from Iron Ore in Wadi Sawawin, Duba, Saudi Arabia
August 2016
Fifteen iron ore samples collected from Wadi Sawawin, Duba, Saudi Arabia were analysed using X-ray diffraction in order to determine mineral composition. Atomic absorption analysis was used to determine concentrations of Al, Ca, Fe, K, Mg, Bi, Pb, Th and U. Natural radioactivity concentrations were determined using gamma-ray spectrometry based on a hyper pure germanium (HPGe) detector; concentrations ranged from...
The third fundamental interaction of atoms
August 2016
It is shown that the existence of fundamental interactions cannot explain the chemical covalent bond. The existence of a new (hitherto unknown) fundamental interaction of atoms-internuclear attraction, which adequately interprets the chemical covalent bonding was proposed. Key words: Fundamental interaction, chemical covalent bonding, internuclear attraction.
The thermal behaviour of gases under the influence of infrared-radiation
August 2016
In contrast to the usual spectroscopic methods, the temperature of a gas embedded in a tube was measured here and not the intensity loss of the radiation. In order to minimize the interference by the tube, light-weight building materials were used, preferably Styrofoam, transparent plastic foils and aluminium foils. Sunlight as well as infrared (IR)-bulbs was employed as radiation sources, whereby near-IR is predominant...
Measurement of natural radioactivity in selected samples of medical plants in Iraq
July 2016
In present study, natural levels of radiation in some selected medical plants existing in the Iraqi stores were estimated to determine any activity concentration, radium equivalent and internal hazard index due to radionuclide, of 238U, 232Th as well as 40K, which occurs naturally. This activity concentration was identified by gamma-ray spectroscopy (NaI(Tl)). The findings indicate that, the rate of activity...
Light source estimation using feature points from specular highlights and cast shadows
July 2016
A method for light sources estimation is proposed in this paper. The method utilizes feature points in cast shadows to estimate near light source positions from estimated source directions using specular highlights. There are several methods that can be used to estimate light sources from scene images, using either cast shadows or specular highlights. However, most of them are limited to directional light sources. The...
Development of an identity management system for a web proxy server in a tertiary institution using anonymity technology
July 2016
The inability of a region to access a webpage, because of the ban being placed on users from that region as a result of its location policy, has led to this study. This problem is often solved by anonymizing web traffic by using The Onion Router (TOR). These tools, however, suffer from the problem of exposure of identity and also lack the ability to monitor web users. This study describes in detail a web proxy server...
Preliminary structural evaluation of an X-Field Onshore Niger Delta using 3D seismic data
June 2016
A structural evaluation of a post stack time migrated (PSTM) 3D seismic data over an X–Field in the eastern Niger Delta has been attempted. The objective of the study is to structurally evaluate the field with a view to identifying structural features such as faults, map geologic horizons and analyze reflection characteristics that might be a good lead to probable hydrocarbon accumulations. Results revealed that...
Geometric phases for two-mode squeezed vacuum state
June 2016
Although the geometric phase for one-mode squeezed state had been studied in detail, the counterpart for two-mode squeezed state is vacant. In this paper, we aim at the special case, namely, two-mode squeezed vacuum state. Furthermore, the total phase factor is to be written in an elegant form, which is just identical to one term of product of two squeezed operators. In addition, when this system undergoes cyclic...
Determination of the characteristic parameters for the modified Bessel-Gauss beams
June 2016
Some characteristic parameters of the Bessel- Gaussian beam were determined theoretically by direct analytical calculations. Variation of the final beam radius (ω) with the starting beam radius (ωo) was studied. The Rayleigh range of a Bessel-Gauss beam was calculated for each value of the minimum starting beam radius. The beam wavefront radius of curvature (R) was calculated as a function of starting...
Matter-antimatter models in cosmic and biologic systems
June 2016
The leading theories suggest that in the first fractions of the second following the Big Bang, equal amounts of matter and antimatter were formed, and annihilated. Therefore, the asymmetry of matter and antimatter, and formation of the visible universe is one of the major unsolved problems in physics. Surprisingly, when the major characteristics of the cosmic matter- antimatter interactions, were compared to...
Direct method for solving nonlinear strain wave equation in microstructure solids
May 2016
The modeling of wave propagation in microstructure materials should be able to account for the various scales of microstructure. In this paper, the extended trial equation method was modified to construct the traveling wave solutions of the strain wave equation in microstructure solid. Some new different kinds of traveling wave solutions was gotten as, hyperbolic functions, trigonometric functions, Jacobi ...
Solar flare effects (SFE) on geomagnetic fields across latitudes
May 2016
A comprehensive study of Solar Flare Effects (SFE) across latitudes has been carried out using an extensive data set of two geomagnetic elements H and Z selected from 1997 to 2005. The X (intense) and M (medium) solar flares were examined under quiet conditions. Nine stations extending from equatorial to high latitudes were used in the study. Data employed in this work include minute data of geomagnetic field, solar...
Purity-performance relationship of anthocyanidins as sensitizer in dye-sensitized solar cells
April 2016
A comparative analysis between crude and purified extracts obtained from withered leaves of Terminalia catappa (T. catappa) and pure compounds of anthocyanidins as organic sensitizers in solar cells. The chemical and electronic properties of the extracts and the pure anthocyanidins were examined using spectroscopic studies: ultraviolet (UV), Fourier transform infrared (FT-IR) and gas chromatography coupled with flame...
Slip flow of a second grade fluid past a lubricated rotating disc
April 2016
Slip flow of a second-grade fluid past a lubricated rotating disc is studied. The disc is lubricated with a power-law fluid. The interfacial conditions between fluid and lubricant are imposed on the surface of disc by assuming a thin lubrication layer. The numerical solutions are obtained using Keller-Box method. The effects of slip parameter and Weissenberg number on the three components of fluid velocity and pressure...
Analysis of elastic scattering data below, atop and above the delta resonance using inverse scattering theory
April 2016
The simple local optical potential adopted in analyzing successfully elastic scattering data in the delta resonance region has been emphasized here. This is based on obtaining the same nature for the potential by extracting potential points from available phase shifts at 114, 163, 240 and 340 MeV using inverse scattering theory within the framework of Klein-Gordon equation. Luckily, and as expected, the...
Dielectric study of calcium doped barium titanate Ba1-xCaxTiO3 ceramics
March 2016
Calcium doping effect on the ferroelectric properties of Ba1-xCaxTiO3: BCTx (x = 0.01, 0.05, 0.1) ceramic material prepared via the sol-gel process was studied. X-ray diffraction (XRD) showed that the powders of calcined BCTx at 900°C crystallize in a pure phase of perovskite type without secondary phases. Microstructural morphology was analyzed by Scanning Electronic Microscopy (SEM). Dielectric measurements were...
A new solitary wave solution of the perturbed nonlinear Schrodinger equation using a Riccati-Bernoulli Sub-ODE method
March 2016
The Riccati-Bernoulli Sub-ODE method is used for the first time to investigate exact wave solution of the perturbed nonlinear Schrodinger equation with Kerr law non linearity which describes the propagation of optical solitons in nonlinear optical fibers that exhibits a Kerr law non linearity. An infinite sequence of exact solutions can be obtained according to Backlund transformation. The proposed method also can be...
Investigating H and Z geomagnetic component disturbance field in the mid-latitude
March 2016
The relationship in the variations of geomagnetic horizontal component (H) and vertical component (Z) in Boulder station (40.1°N, 254.8°) has been investigated. In the analysis, series of significant changes in amplitude and period are observed in H as well as in Z during the day-time. The changes in H and Z for the average yearly diurnal variations and for the monthly variations do not exhibit consistent...
Space charge kinetic treatment in Langmuir probes with cylindrical geometry
March 2016
In this paper, an analysis of the space charge build up in the interelectrodic region of a velocity analyzer with cylindrical symmetry is performed using kinetic theory. Thus the present treatment includes temperature effects. Azimuth symmetry is also assumed. A detailed and comparative analysis, between planar and cylindrical electrodes, is carried out, showing the advantages of each kind of...
Biodegradation with heterogeneous catalyst in the production of biogas from wheat wastes, rice husk and spent grains
February 2016
Biodegradation with heterogeneous catalysts were successfully carried out in the production of biogas from wheat wastes, rice husk and spent grains. Five digesters were charged with spent grains/clay soil, spent grains/lime stone, rice husk/clay soil, rice husk/lime stone and wheat wastes/potash, respectively. Clay soil, limestone and potash were used as catalysts for optimizing and to speed up the chemical reactions in...
Analytical model of heavy-particle pollutant transport in estuary
February 2016
The aspects of heavy-particle diffusion in the tropical estuary is investigated. The two dimensional advection-diffusion equations with tidal and settling velocity were solved with steady state approximation. An analytic solution was obtained in term of Cosines Integral function. The results showed that the profile of concentration follow a tidal cycle with the concentration decrease when the tidal speed is low and...
Empirical model for estimation of global radiation from sunshine duration of Ijebu-Ode
February 2016
Empirical models to estimate global solar radiation require the development of a set of equations that relate it to other meteorological parameters and from the monthly average daily value of clearness index and relative sunshine spanning of a period of 5 years, the Angstrom- Prescott model was developed for the estimation of global solar radiation of Ijebu-Ode (Lat. 6.81â°N. Long. 3.92â°E), a tropical region of...
Extraction and characterization of biodiesel from Borassus aethiopum and Cassia sieberiana
January 2016
Biodiesel was successfully produced from Borassus aethiopum and Cassia sieberiana seeds using the trans-esterification method. The biodiesels produced were characterized by physico-chemical properties of acid value, iodine value, specific gravity, refractive index, viscosity, density, flash point, cloud point and pour point. Results showed that the biodiesels produced have values which compared well with the European...
Spectroscopic determination of the electrical parameters of a micro-wave discharge in helium plasma
January 2016
This paper is based on the study of the emitted radiation by electrical discharge plasma, caused in the helium a pressure of 4.8 Torr, a power MW of 108W. The study numerical model allows the identification of several spectral lines. With the Boltzmann method the study have calculated the electronic temperature (Te=3.23eV), it corresponds to the classification scale of plasmas. The application of the Saha law gives the...
Theoretical calculation of half-metallic ferromagnetism in Al1-xVxN compound
January 2016
Using the first-principles in the framework of density functional theory, the structural properties, electronic structure, and magnetism of V-doped aluminum nitride (AlN) were investigated. The calculations were carried out using the method based on pseudopotential, employed exactly as implemented in Quantum ESPRESSO code. For (x = 6.25%) Al0.9375V0.0625N and (x = 12.5%) Al0.875V0.125N concentrations, a half-metallic...
Similarities between basic mechanisms of cosmic and biologic systems
January 2016
Similarities in the birth and development of cosmic and biologic systems provide unexpected proof for the major theories of formation of the universe - the Big Bang and the String theories. They include similarities in the theory of their formation, one unit origin, preexisting states, conception, fertilization, gestation, information, basic units, flatness, fluctuations, smoothness, lumpiness, reproductive and...
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