A model for removing sediments from open channels
February 2014
The problems caused by suspended sediment overloading in open channels are of great importance to the hydraulic engineers. One of the important problems caused by the sediment overloading during flood seasons is the change in bed level and corresponding water level of rivers due to its deposition on the river bed. At the upstream reaches, the bed slope is high, velocity is high and hence the rivers carry large amount of...
Lehmann Type II weighted Weibull distribution
February 2014
We upgrade on the method used on weighted Weibull model proposed by Azzalini (1985) using the logit of Beta function by Jones (2004) to have Lehmann Type II weighted Weibull model with a view to obtaining a distribution that is more better than both weighted Weibull and Weibull distribution in terms of estimate of their characteristics and their parameter. The weighted Weibull distribution is proposed by slightly...
Metamaterials in microwave applications: A selective survey
February 2014
Recently, metamaterial has grabbed prime focus of research fraternity working in the field of antennas, microwave filters and components design. Many different structures of split ring resonators (SRR) for their respective applications have been reported till date. In all of these findings in some way or other, using metamaterial, drastic reduction in size of the component has been achieved. Thus, the metamaterial can...
A planar microstrip metamaterial resonator using split ring dual at Ku-Band
February 2014
This paper introduces a new planar microstrip metamaterial resonator, the novelty of this paper lays in its unit cell design. The unit cell is formed by connecting metallic traces of two edge coupled split ring resonators to form the infinity symbol on one side of the substrate, and an array of conducting wires on the other. An RLC equivalent model of the structure is also proposed, it can be advantageous to use this...
Silver nanoparticles biogenic synthesized using an orange peel extract and their use as an anti-bacterial agent
February 2014
Synthesis of nanoparticles by green methods with antibacterial properties is of great researchers’ concern in the explored of new pharmaceutical and biomedical products. In this study, we synthesized a new product of nanosized particles of silver, non-toxic economy, clean, and conservator for energy. An environmentally friendly route is used for synthesizing silver nanoparticles (AgNPs) using an orange peel...
Development of a multilayer perceptron (MLP) based neural network controller for grid connected photovoltaic system
February 2014
This paper focuses on the development of a controller for grid connected photovoltaic energy conversion system. Control design of a single phase inverter interfacing a photovoltaic generator and an electrical grid is performed, based on Artificial Neural Networks. The developed controller is compared with a Proportional Integral (PI) controller through computer simulation. The obtained results show that the neural...
Simulation of 4Ï€ HPGe Compton-Suppression spectrometer
January 2014
Compton-suppression spectrometer is well suited to the analysis of low levels of radioactive nuclides. Monte Carlo simulations can be a powerful tool in calibrating these types of detector systems, provided enough physical information on the system is known. A simplified Compton-suppression spectrometer model using the Geant–4 simulation toolkit was discussed. The spectrometer model was tested to evaluate photo...
Vectorial reduced differential transform (VRDT) method for the solution of inhomogeneous Cauchy-Riemann system
January 2014
It is well known that initial-value problem for the Cauchy-Riemann system is ill-posed and the problem with such Hadamard instability cannot be solved unless the initial data are analytic. In this paper, we present the vectorial reduced differential transform (VRDT) method to solve initial-value problem for the inhomogeneous Cauchy-Riemann system with analytic data. The VRDTM solution vector achieved is in the form of...
Study of optical constants in Se- In –Pb thin films of chalcogenide glasses
January 2014
Bulk glasses of Se75 In25-x Pbx (when n = 0, 4, 6, 10) systems and thin films have been prepared by the conventional melt quenching technique and by thermal evaporation technique, respectively. The optical constants (absorption coefficient (α), refractive index (n), extinction coefficient (k)) have been studied for Se-In-Pb thin films as a function of photon energy in the wavelength range (300-900 nm). Spectral...
A four-point fully implicit method for the numerical integration of third-order ordinary differential equations
January 2014
In this paper, we derived a continuous linear multistep method (LMM) with step number k = 4 through collocation and interpolation techniques using power series as basis function for approximate solution. An order-seven scheme is developed which was used to solve the third-order initial value problems (IVPS) in ordinary differential equation without first reducing to a system first-order. Taylor’s series algorithm...
Determination of some physical and mechanical properties of Calabrian pine (Pinus brutia Ten.) trees grown in the Denizli area of Turkey
December 2013
The most extensive distribution of Calabrian pine (Pinus brutia Ten.) trees in the world is found in Turkey. This species varies depending on the regions in Turkey for growth features, such as climate, soil structure and slope. In this study, the technological properties of Calabrian pine (Pinus brutia Ten.) grown in the Denizli area were studied. Within the scope of the study, their physical properties, such as...
The application of some biodiversity indices in the Tortum Stream, Erzurum, Turkey
December 2013
The aim of the present study was to investigate biodiversity index, dominancy index and equivalence index of diatom community in the Tortum Stream and its tributaries. Diatom samples were collected from nine stations on the main river and tributaries between July 2012 and May 2013. A total of 36 taxa of Bacillariophyceae were identified. Dominant species was Cocconeis placentula in all stations. Biodiversity...
Application of vertical electrical soundings to characterize aquifer potential in Ota, Southwestern Nigeria
December 2013
A knowledge of hydrogeophysical parameters of aquifers is essential for groundwater resource assessment, development and management. Traditionally, these parameters are estimated using pumping test carried out in boreholes or wells; but this is often costly and time consuming. Surface geophysical measurements can provide a cost effective and efficient estimates of these parameters. In the present work,...
Evaluation of noise reduction in a cigarette factory, China
December 2013
Millions of workers are exposed to occupational noise that increases their risk of hearing impairment and evidence on the effectiveness of precaution is lacking. This study was undertaken to assess the effect of noise control strategy in a cigarette factory in China. We chose the representative points in the unit, monitored the noise level and analyzed frequency spectrum at the same workplace before and after sound...
Heavy metal concentration in soil of some mechanic workshops of Zaria-Nigeria
December 2013
This research paper investigated the elemental composition of soil samples from four selected mechanic workshops in Zaria. A total of eight samples were analyzed at Centre for Energy Research and Training (CERT) Ahmadu Bello University Zaria using standardless X-Ray Fluorescence spectroscopy (XRF). From the result, it was found that Silicon (Si) has the highest mean concentration ranging from 0.0013-0.0024 ppm and Ba,...
An appraisal of the water related contaminants as they affect the environment around the Enugu coal mines of Enugu state, southeastern Nigeria
December 2013
Enugu metropolis is within the Anambra basin, which comprises mainly sedimentary rocks of sandstone, siltstone, mudstone and shales in the Lower Benue trough and as the capital of Enugu state in Nigeria and also as one of the major municipal and industrial centers in southeastern Nigeria experiences much groundwater contamination due to coal mining activity. The Area is richly endowed with sub-bituminous three-coal...
Discrete singular convolution for Lennard-Jones potential using Shannon kernel
December 2013
In this paper, the idea of discrete singular convolution (DSC) as a viable computation method for analyzing physical systems has been underlined. Discrete singular convolution has been used for solving the Schrödinger equation for water molecules, subject to the Lennard Jones potential, and the DSC differentiator has been used for obtaining the energy eigen-states of water, for a given grid size for discretization,...
Numerical solution for a class of singular integral equations
December 2013
This paper is concerned with finding approximate solution for the singular integral equations. Relating the singular integrals to Cauchy principal-value integrals, we expand the kernel and the density function of singular integral equation by the sum of the chebyshev polynomials of the first, second, third and fourth kinds. Some numerical examples are presented to illustrate the accuracy and effectiveness of the present...
Similarities between photosynthesis and the principle of operation of dye-sensitized solar cell
December 2013
Photosynthesis is the process of converting light energy into chemical energy and storing it in the bonds of sugar; while the operational principle of the dye-sensitized solar cell involve the absorption of light by a dye adsorbed by a photoanode. Electrons are released when the dye is illuminated. The comparison done here showed that there exist a lot of similarities between photosynthesis and the principle of...
Adsorption study of Nymphaea alba for the removal of manganese from industrial waste water
December 2013
The application of adsorbents obtained from Nymphaea alba as a replacement for costly conventional methods of removing heavy metal ions from waste water has been reviewed. Detailed adsorption study of manganese on N. alba was investigated. Batch adsorption study was carried out as a function of amount of adsorbent, contact time, thermal treatment, pH and agitation speed. The adsorbent to solution ratio and the metal ion...
Homotopy analysis method with modified Reimann-Liouville derivative for space fractional diffusion equation
November 2013
In this paper, we applied the homotopy analysis method (HAM) to construct the analytical solutions of the space fractional diffusion equations. The derivatives are defined in the Jumarie’s fractional derivative sense. The explicit solutions of the equations have been presented in the closed form by using initial conditions. Two typical examples have been discussed. The results reveal that the method is very...
Feasibility and technical studies of two water recirculating systems using two different power sources, solar photovoltaic and fuel generator
November 2013
Recirculating water systems are designed to minimize or reduce dependence on water exchange and flushing in fish culture units. Water is typically recirculated when there is a specific need to minimize water replacement, to maintain water quality conditions which differ from the supply water, or to compensate for an insufficient water supply. In this work, recirculating system of fish was used in rearing fish which...
Optimization of the louver angle and louver pitch for a louver finned and tube heat exchanger
November 2013
The optimization of the louver angle (θ) and the louver pitch (Lp) for a louver finned and tube heat exchanger was investigated numerically along with a simplified conjugate-gradient method (SCGM). The area reduction ratio relative to a plain surface is the objective function to be maximized. A search for the optimum louver angle (θ) and louver pitch (Lp), ranging from 15°< θ < 40° and 2...
Crustal and upper mantle electrical conductivity structure in north central Nigeria
November 2013
Separated spherical harmonic analysis coefficients of the external and internal parts of the observed quiet-day geomagnetic field variations (Sq) for the North Central Nigeria were used to determine the conductivity profile to depths of about 873 km by Schmucker equivalent substitute conductor method. Within the crust, the conductivity increased from 0.027 S/m at a depth of 7.4 km to 0.074 S/m at 15.5 km and 0.098 S/m...
Radon assessment in ground water sources from Zaria and environs, Nigeria
November 2013
Groundwater (well and borehole) samples from various locations of Zaria and environs including Sabongari, Tudunwada, Danmagaji, Samaru and Bomo have been investigated for their 222Rn concentrations by liquid scintillation counter. The concentration of 222Rn in open well water was found to vary in the range (0.77-28.37) Bq/L and (2.32-48.80) Bq/L for borehole, with a geometric mean of 12.43 and 11.16Bq/L for borehole and...
Synthesis, growth and characterization of picolinic acid hydrochloride: A novel semiorganic nonlinear optical single crystal
November 2013
Nonlinear optical single crystals of picolinic acid hydrochloride (PHCL) were grown by the slow evaporation method. The grown crystal was subjected to a single crystal X-ray diffraction analysis, to confirm that it belongs to the orthorhombic structure. The Nonlinear Optical (NLO) property of the crystal is confirmed with the emission of green radiation from the crystal under the illumination of laser radiation (106.4...
Optimal lead-lag controller designing for reduction of load current total harmonic disturtion and hanmonic with voltage control using honey bee mating optimization (HBMO)
November 2013
Increase in world demand load has resulted in new distributed generation (DG) that has entered into the power system. One of the most renewable energies is fuel cell, which is connected to power system using a power electronics interface in microgrid or standalone condition. The highest problem of this switching interface based DGs is the power quality (PQ) and harmonics of currents. Also, the voltage of the DGs should...
Theoretical and experimental studies for wool wax recovery by flotation
November 2013
Theoretical and experimental studies have been performed to analyze the flotation processes for recovery of wool wax from an industrial effluent by air flotation. Batch flotation process was carried out at different experimental conditions and different air flow rates. The results obtained show that wool wax can be successfully recovered from the tested effluent using batch air flotation. The percentage of wax recovery...
Predicting geotechnical parameters of fine-grained dredged materials of the gulf of Izmit (NW Turkey) using the slump test method and index property correlations
November 2013
In this study, an attempt has been done to figure out the geotechnical properties of physically remolded dredged materials of the Gulf of Izmit located in NW Turkey, by using slump test method. For this aim, slum tests were conducted on dredged material specimens using open-ended polyvinyl chloride (PVC) cylinders of 10 cm diameter and height. Water content of the dredged material specimens was obtained in the...
Characteristics of supercritical flow in rectangular channel
October 2013
The present study deals with the supercritical flow characteristics and the effort has been made to verify analytical and empirical relations based on extensive experimentation for different characteristics namely: sequent depth ratio (h2/h1), efficiency of jump (E2/E1), relative height of jump (hj/E1) and relative length of jump (Lj/h2). Also, the existing models for different channel conditions are discussed;...
Empirical analysis of road traffic accidents: A case study of Kogi State, North-Central Nigeria
October 2013
This paper studied the trend of road accident in Kogi State from January, 1997 to December, 2010, using a univariate time series data collected from the Federal Road Safety Commission (FRSC), Lokoja, Kogi State. The model for the data was found to be Y = 22.062 + 0.252T. Test for the existence of trend and seasonal variation was conducted at 0.05 level of significance, and a four years forecast for road accident was...
Effects of heat absorption and chemical reaction on a three dimensional MHD convective flow past a porous plate
October 2013
An attempt has been made to investigate the effects of heat sink and chemical reaction on a three dimensional Magneto hydrodynamics (MHD) convective flow with mass transfer of an incompressible viscous electrically conducting fluid past a porous vertical plate with transverse sinusoidal suction velocity. A magnetic field of uniform strength is assumed to be applied transversely to the direction of the main flow. The...
Comparative performance of Raman-SOA and Raman-EDFA hybrid optical amplifiers in DWDM transmission systems
October 2013
To combine the benefits and compensate for the drawbacks of different optical amplifier types, a hybrid amplifier can be composed. The authors consider two most frequently used hybrid amplifiers that can provide better performance: a semiconductor optical amplifier (SOA), and an erbium doped fiber amplifier (EDFA), both in combination with a distributed Raman amplifier (DRA). To compare performance of the hybrid...
Studies on the mechanical properties of glycine lithium chloride NLO single crystal
October 2013
The microhardness study reveals the mechanical strength of the grown crystal. The Vicker’s and Knoop hardness studies were performed to understand the mechanical behavior of the glycine lithium chloride crystals. The Vicker’s and Knoop microhardness numbers (HV and HK) for the crystal were found for different loads. It is found that these numbers increase with an increase in the load. The Mayer’s index...
Evaluation of thermal mud characteristics of Erzurum (Köprüköy) clayey raw materials (NE Turkey)
October 2013
In Turkey, there are several natural occurrences of clays/muds which are used for therapeutic, aesthetic, and pharmaceutical purposes. The aim of this study was to assess the mineralogical and physicochemical properties of Erzurum clayey raw materials from Koprukoy (Erzurum, NE Turkey) for their therapeutic purposes. Raw material samples were collected from Pliocene geological formation...
Sensitivity of thin film nanocrystalline silicon properties to radio frequency plasma-enhanced chemical vapor deposition (rf PECVD) parameters
October 2013
Hydrogenated nanocrystalline silicon (nc-Si:H) films for efficient nc-Si:H solar cells are made at the transition to the nanocrystalline regime during radio frequency plasma-enhanced chemical vapor deposition (rf PECVD). This transition occurs within a sensitive process window and is affected by various deposition parameters. This paper reports an investigation into the material properties of nc-Si:H films as...
The novel terms on the basis of some photon interaction parameters for some barium compounds
October 2013
The molecular (), atomic (), electronic () cross-sections and the total mass attenuation coefficient () values of barium compounds are determined both experimentally and theoretically. The most interesting result of this study is that the effective , , cross-section values are not as expected near the absorption edge. The results have been compared with some other theoretical values...
Some classification results on totally umbilical proper slant and hemi-slant submanifolds of a nearly Kenmotsu manifold
October 2013
This paper is concerned with the study of slant and hemi-slant submanifolds of a nearly Kenmotsu manifold. We prove that every totally umbilical proper slant submanifold of a nearly Kenmotsu manifold is totally geodesic and derive the integrability conditions of involved distributions in the definition of a hemi-slant submanifold. Finally, we obtain a classification theorem on a totally umbilical hemi-slant...
Partitioning large ontologies based on their structures
October 2013
With awareness of ontology capabilities in processing semantic web information, the number of ontologies have been increasing over the past decade. However, there are still some difficulties in working with ontologies having large sizes (that is having considerable amount of concepts and relationships) resulting from high time and space complexity of the processing involved. To overcome these...
Usage opportunities of the natural dye extracted from acorn (Quercus ithaburensis Decaisne) in the furniture industry upper surface treatment
October 2013
This study is aimed to develop a natural dye to be used in the furniture industry upper surface treatment and to be sensitive to the environment and human health. For this reason, the natural dye extracted from acorn (Quercus ithaburensis Decaisne) is applied to different types of wood. After that, the determination of color change under the accelerated weathering...
Equivalence principle of light’s momentum harmonizing observation from quantum theory to cosmology
October 2013
Unlike in Newtonian mechanics, in the theory of relativity, the coordinate axis is not fixed, and the time axis serves as the background for the observation. In other words, the theory of relativity is background independent (BI). The quantum theory created in the micro-world, in contrast, is background dependent (BD). Efforts to unify both by BI have not yielded much success. In addition, it is recognized that we...
Convolutive cyclic voltammetry studies of PVA/CuI polymer composites at gold electrode
October 2013
Cyclic voltammetry of PVA/CuI polymer composites was studied in acetonitrile as a solvent containing Tetrabutylammonium tetrafluoroborate (TBAFB). Cyclic voltammogram of PVA/CuI polymer composites exhibited unidirectional oxidative peak in the forward scan and irreversible reductive peak in the negative scan. The voltammetric behaviour explored that the electrode reaction of the investigated composite proceeds as EC...
Differential transform method for solving non-linear systems of partial differential equations
October 2013
The differential transform method (DTM) has been applied to solve many functional equations so far. In this paper, we propose this method (DTM), for solving nonlinear Jaulent-Miodek and the Hirota-Satsuma equation. Numerical solutions obtained by differential transform method are compared with the exact solutions and that obtained by Adomian decomposition methods. The results for some values of the variables are shown...
Determination of trace elements in nutrition materials in Kingdom of Saudi Arabia
October 2013
Four types of edible tubercular roots cultivated in Saudi Arabia are analysed through sequential determination of certain essential and toxic trace elements by inductively coupled plasma atomic emission spectrometry (ICP-AES). Comparable runs carried out using both flame and graphite atomic absorption spectroscopy (AAS). Radish proved to contain the highest concentration level of iron (>21 μg/g), onion contains...
A Google map-based traffic accident reconstruction system
October 2013
Both traffic accident reconstruction and responsibility confirmation of traffic accident depend on crash scene diagramming and crash simulation. However, mistakenly recorded road geometry of the crash scene usually causes misunderstandings in the crash scene diagramming and thus the result of accident reconstruction is untrustworthy. Research has thus been continuously done to solve the...
Possible internuclear interaction of atoms
October 2013
This work had been devoted to the problem of the nature of forces between molecules of second liquid. A hypothesis of the internuclear interaction of atoms was proposed. But this hypothesis turned out to be suitable also for the interpretation of the chemical covalent bond. It was offered a new model of hydrogen molecule, based on the corpuscular properties of electrons (together with the wave ones). This model did not...
Solitary wave solutions of fifth-order (1+1)-dimensional Caudrey-Dodd-Gibbon equation
October 2013
The manuscript deals with the abundant travelling wave solutions of the Caudrey-Dodd-Gibbon (CDG) equation which have been obtained in a uniform way by using alternative (G`/G)–expansion method wherein the generalized Riccati equation is used. Moreover, a relatively new technique which is called (U`/U)-expansion is also used to find solitary wave solutions of CDG equation. The solutions obtained in this...
A tuneable metamaterial design using microelectromechanical system (MEMS) based split ring resonator (SRR)
October 2013
In this paper, we present a study of tuneable equilateral triangular shaped spilt ring resonator (ETSRR). In this ETSRR we rotate the inner and outer rings by varying the position of the splits in rings. For this we used radio frequency microelectromechanical system (RF MEMS) switches. By making MEMS switches ON/OFF, the positions of splits in the rings were varied which can be considered as rotation of rings. As we...
Efficient coupling of light wave into slow modes planar photonic crystal slab waveguides
October 2013
The generation of the slow modes in a planar photonic crystal waveguide has been highlighted theoretically and experimentally in the two last decade. However, the exploitation of this phenomenon to control the light propagation in the optical integrated circuits faces several obstacles and technological locks. On the one hand, it is almost impossible to excite this type of modes in the slowing light devices because of...
Variation of source distribution of total oxidants: Contributions of oxides of nitrogen, sulphur (IV) oxide emissions and background ozone from Lagos-Nigeria
October 2013
Air dispersion modeling system (ADMS)-urban was used as air dispersion tool to model the atmospheric pollutants composition over Lagos air shed. The model runs with single point source showing the variation of concentrations of air pollutants (NO2, NOx, O3, and SO2) with ambient air dispersion over the city of Lagos, Nigeria. This city is located in the coastal area, and is highly congested with a high intensity of...
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