Journal of Scientific and Engineering Research

1-10

Authors: Etim D. Uko, I. Tamunobereton-ari, Valentine B. Omubo-Pepple, Progress J. Loveday

Subsurface temperatures and lithologies from oil wells in the north-western Niger Delta are here presented. Data consist of 1,010 temperatures and corresponding 1,010 sand-shale percentages recorded on eight oil-well continuous-temperature and Gamma Ray logs. The temperatures and sand-shale volumes were cross-plotted with depth. The results show geothermal gradients with corresponding well-defined vertical lithostratigraphic units. For the upper sandy lithology, the Benin Formation, the geothermal gradients vary between 0.00115oCm-1 to 0.02209 oCm-1 with an average 0.00947oCm-1. For the lower shaley lithology, the Agbada Formation, the gradients vary between 0.008300 oCm-1 and 0.12000 oCm-1 with an average of 0.03717 oCm-1. The gradients in the Agbada Formation are higher than those in Benin Formation validating the fact that temperature increases with depth. Sand volume decreases while shale volume increases with increase in depth. The depth of Benin Formation is variable in the study area ranging between 800m and 1500m subsea. The results of the calculated geothermal gradients together with the subsurface lithology can be used in engineering, science and oil-gas exploration in the study area.

14-17

Authors: A.T. Mamadalimov, N.K. Khakimova, R.U. Khakimova

The photoconductivity (PC) of the cotton fibers (CF) grade “F175” doped by iodine is investigation. The samples discovered a long-term relaxation of the PC after irradiation (hv=5 eV of the iodine doped CF and have been found infrared quenching at combined illumination.

25-31

Authors: Philomena K. Igbokwe, Kingsley C. Egemba

This paper discusses the application of hybrid mechanistic-neural network modeling approach to chemical engineering processes. The main features, advantages and disadvantages of the mechanistic, conventional neural network and the hybrid models have been highlighted. Various configurations/coupling arrangements for the application of hybrid mechanistic-neural network modeling to chemical processes are presented. In all the reported applications, the hybrid models predicted and extrapolated the processes better than either the mechanistic model or the neural network model, and have been shown to offer advantages over these conventional modeling approaches, in modeling poorly understood or complex processes. The application of the hybrid mechanistic-neural network modeling to the atmospheric distillation column of an existing crude oil refinery, and a suitable hybrid configuration for implementation is also presented. This approach can be used to improve the accuracy of predictions from shortcut distillation models when applied to existing columns.

40-56

Authors: Maytham Al-Neama, István Farkas

One of the most important applications of solar energy using is air heating generally and solar drying especially. Solar dryers are used mostly for agricultural products moisture content reducing to a level which prevents them to get damage. To classify drying systems, many methods have been discussed in the last studies. According to air movement through the drying system, the dryers classified into: active and passive dryers. Also, based on the construction of these systems, dryers classified into: direct and indirect dryers. There are various computer software which used to design, optimize, describe and estimated the performance of different solar drying systems. Different types of software such as MATLAP, FORTRAN, ANSYS, CFD techniques,…, etc. have been applied for thermal analysis for solar drying systems. The economic viability of solar drying, therefore, depends on the drying cost compared to the market cost. Different criteria have been proposed and applied to characterizing the economical background of solar systems. According to the mentioned classifications above, a literature review has been done with this paper to show the main influential factors and different designs for such systems.

66-72

Authors: Darius P.B. Yusuf, Precious N. Bala, Lambawan T. Wancy

There are multiple misconceptions about preventive maintenance; one such misconception is that preventive maintenance is unduly costly. This research work dictate that it cost more for regular scheduled down time and maintenance than it will normally cost to operate equipment’s until repair is absolutely necessary one should compare not only the cost but the long term benefits and saving associated with preventive maintenance. The data generated for this study are presented in tables. This simplified the arrangement of the data in sequential order for easier analysis and interpretation. The table presented shows the running cost per year and resale prices of certain make (Power Tiller Machine). The result indicates that the average total cost ATCnis minimum during 5th year. There is the need to look at the mathematical approaches in this system through which replacement policy could assist agricultural mechanization to tackle problems of preventive maintenance.

81-86

Authors: John Chibunna Babington, Chamhuri Siwar, Ezerie Henry Ezechi

This study investigated the respondent’s characteristics of recycling behavior and preference of e-waste recycling method of Universiti Kebangsaan Malaysia (UKM) employees and students using a logistic regression analysis in SPSS. Willingness to participate (WTP) was used as the dependent variable. The study found that the significant influencing factors for the behavior of the respondents were awareness on e-waste, perception on repair or refurbishment of EEEs, attitude towards disposal, perception on the establishment of e-waste scheme and concern on toxic content in e-waste for the employee category. The significant influencing factors for the student category were awareness on e-waste and perception on the establishment of e-waste scheme. The coefficient of the predicting power of the dependent variables at 95% confidence level for the employee and student categories were 77.4% and 83.3%, respectively. It is pertinent to understand the behavioral and psychological factors influencing household recycling activities and form effective recycling programs and government strategies based on this information.

100-129

Authors: Edisson Sávio de Góes Maciel

In the present work, a study involving aspectral method to solve the reactive Euler and Navier-Stokes equations is performed. The Euler and Navier-Stokes equations, in conservative and finite volume contexts, employing unstructured spatial discretization, on a condition of thermochemical non-equilibrium, are studied. The spectral method presented in this work employs collocation points and variants of Chebyshev and Legendre interpolation functions are analyzed. High-order studies are accomplished to verify the accuracy of the spectral method. The “hot gas” hypersonic flows around a blunt body, and around a double ellipse in two-dimensions are simulated. The Van Leer and the Liou and Steffen Jr. flux vector splitting algorithms are applied to execute the numerical experiments. The Euler backward integration method is employed to march the schemes in time. The convergence process is accelerated to steady state condition through a spatially variable time step procedure, which has proved effective gains in terms of computational acceleration (see Maciel). The reactive simulations involve Earth atmosphere chemical model of five species and seventeen reactions, based on the Saxena and Nair model. N, O, N2, O2, and NO species are used to accomplish the numerical comparisons. The results have indicated that the Chebyshev collocation point variants are more accurate in terms of stagnation pressure estimations, with errors inferior to 17.00% in the worst case, and in terms of lift coefficient estimations. Moreover, the Legendre collocation point variants are more computationally efficient.

165-173

Authors: Asif uz Zaman, Mohamed F. Soliman

All the Arab countries are struggling with the curse of water scarcity to different degrees of vulnerability. Most of these countries are naturally water scarce with 87% of the area being covered with desert, turning the region into an extremely arid or an arid zone, possessing only 1% share of the total water resources of the world. Due to the lack of fresh water resources in the region, the inhabitants of the region receive a low share of renewable water resources of the world equivalent to one-eighth of the share that a global citizen is blessed with. The struggle of the Arab countries pertinent to water is going to further intensify in the future in the wake of a variety of reasons including excessive demographic growth, climate change, urbanization, industrialization, lack of public awareness and inclination towards sustainable consumptive practices and sometimes affluent style of living. The excessive demand for water will further strain the already vulnerable conventional and non-conventional water supply system of the region requiring immediate technological interventions to address the problem. The water Managers and the policy makers should resort for measures of striking a balance between the water supply and demand before the situation of water scarcity culminates to a much adverse crisis of regional conflicts. There are two popular approaches of ensuring water security; a traditional water supply management approach and a more recent demand management approach. In this paper, the traditional water supply management approach for ensuring water security of the Arab countries is highlighted along with the Water supply and demand scenario of the region. In addition, some disruptive innovative techniques for managing water supply are also suggested to increase the water supply to the region. This paper limits the discussion to the water supply management approach by deliberately not touching upon the demand management approach, in order to prudently restrict the length of the paper.

181-190

Authors: Solomon T. Orumu

A Novel method is developed in this paper for the determination of the conformity factors for different shapes and sizes of concrete samples with relationship to 150mm cube. Induced eccentricity in the samples tested is the determinant of the conformity factor. This eccentricity computed was from experimental data for various lengths to breadth ratio of test samples. The result of this study support the relationship between standard cylinder compressive strength and standard cube compressive strength in EN 206 and establishes new results for smaller sizes. Produced in this paper are Tables of factors to convert from any size to another, which hitherto may not have existed. The use of small size cubes and certification of designed concrete if encouraged will promote sustainability in concrete construction.

198-209

Authors: Humiras Hardi Purba, Kurnia Sigma Indarto, Siti Aisyah

In this globalization era all companies are trying to improve their competitiveness among others by optimizing their operational processes. This is made to increase their revenues and to reduce their costs. A logistics company engaged in export may optimize the space in the rack. The use of this rack is in line with the plan of space optimization in the container. In actual conditions, operators and the warehouse staffs use best practices in determining the items filled into the rack (puzzling), to decide what items to be filled into the rack. But of course it takes much time, especially when the items to be inserted in the rack are in large quantity and of various types. This study will use a software of decision support system (DSS) to calculate the optimization. The target of this study will be a proof that by using the software the job will be easier and better results compared to using best practice. After calculation we got the first optimized calculation result can be achieve 99.57% steel rack efficiency rating for 1st RV5 steel rack and 62.69% for RV5 steel rack type. The total number of RV5 reached 2.32 m3 of the total space on the 2.33 m3 steel rack. Although the total number of RV14 reaches 2 m3 of the total space on the 3.19 m3 steel rack.

224-239

Authors: Abd EL-Rahman Megahid Ahmed, Omar Ahmed Farghal, Ahmed Mohamed Sayed, Moataz Mmdoh Azzaz

This paper presents a nonlinear Finite Element Analysis (FEA) that has been carried out to simulate the behavior of modes failure of Reinforced Concrete (RC) beams strengthened in shear by Fiber Reinforced Polymer (FRP) laminates. Sixty two beams were adoptable in FEM model software using ANSYS. Six beams of them were adoptable in ANSYS and validation of experimental results, three of this sex beams were control beam without strengthened and other beams were strengthened with Basalt Fiber Reinforced Polymers (BFRP). From the analyses of relationships the load with deflection, crack pattern, first crack load and ultimate load was obtained and compared with the experimental results available in laboratory. The load deflection plots obtained from numerical studies show good agreement with the experimental plots. There was a difference at the behavior between the RC beams strengthened with and without BFRP layers. The prediction models that were proposed by considering all common parameters that influence the ultimate shear capacity of strengthened beam including beam width, concrete strength, effective height of the beam, FRP thickness, height of FRP sheet, strengthening configuration (completely wrapped, U-jacketing and side bonding). Therefore, the models of the experimental beams can be adoptable in ANSYS and validation of experimental results can be done using ANSYS.

244-249

Authors: Essam Mahmoud Ibrahim

In the relative humidity measurements, many factors are effect in the response time of dew-point meter. In calibration system, it was used dew-point meter. So, this paper illustrate the effect of gas flow rate in the response time of dew-point meter measurements. Gas flow rate has effect in the dew-point meter response time. Response time is important in calibration process to determine the waiting time to stable the calibration system and start to record the measurement. All parameter are fixe but the flow of dew-point meter pump changed from 20 L/H to 60 L/H. The dew-point meter has flow controller to change the flow. In case that all parameters of two-pressure generator are fix, the measurements shows that when the flow is slow, the response time of the sensor of dew-point meter was slow. When the flow is fast, the response time of the sensor of dew-point meter was fast. Also from this paper we find the relationship between flow rate and response time of dew-point meter. In addition, the flow rate is one of important uncertainty sources. It was effected by two items, first is stability and second is reproducibility.

256-262

Authors: Özen Özboy Özbaş, İbrahim Tuğkan Şeker, İncilay Gökbulut

In this study, utilization of apricot kernel flour (AKF) as fat replacer in cookies was examined and shortening content in a wire-cut cookie formulation was reduced at 30% and replaced with AKF. Also, the effects of apple powder (APL-P) at the levels of 10, 20, 30 and 40% (w/w) on the quality of low-fat cookies were investigated. As a by-product, apricot kernel offers an exciting new potential as a food ingredient especially in cereal. A new form of apple (Malus domestica) as freeze-dried powder retaining all important nutrients such as dietary fiber and flavor of fresh apple might be promising alternative for the utilization of apple. Results showed that there were no significant differences between spread ratio values of the cookies supplemented with different levels of APL-P and control and they were all acceptable (p<0.01). The hardness values of the cookies increased significantly (p<0.01) with APL-P level up to 20% and the hardness values for the 30 and 40% addition levels were not detected. Overall sensory scores of the cookies supplemented with APL-P were not significantly different from those of the control until 30% addition level. Total dietary fiber contents of the cookies increased with increasing APL-P supplementation (from 12.24% to 23.68%). Although the lightness (L*) of the cookies supplemented with APL-P decreased significantly (p<0.01), cookies supplemented with APL-P generally gave higher a* and b* values at all levels. With the production of high-fiber and low-fat cookies by the usage of AKF and APL-P especially in cereal products are offered.

275-280

Authors: Faisal H Nesayef

Pregroups was constructed by Stallings in 1971. Subsequently the concept of Pregroups was developed by many other researchers. Stallings originally defined a set with a binary operation satisfying five axioms, namely, P1, P2, P3, P4, and P5. Later it was proved that P3 is a consequence of the other axioms. Stallings has also linked this construction of a Pregroup to Free Product of Groups. This construction is developed to include a new axiom called P6, which enabled to define a length function on the universal group of Pregroups. Applications of Pregroups with length functions led to direct proofs of many other concepts in combinatorial group theory. On the other hand the concept of length functions on groups was first introduced by Lyndon [1]. This was used to give direct proofs of many other results in combinatorial group theory. Further work was done by many other researchers such as, Cheswell [2], [3], [4], Hoare [5], Wilkins [6], etc.

293-299

Authors: S. Suleiman, N. Shehu

Knowledge of volatility is of crucial importance in many areas. The variability in the foreign exchange markets means huge losses or profits by investors. Therefore, the idea of estimating the market fluctuations is thus is very significant as this can help investors plan well for their investment returns from the market. Due to complex nature of the financial markets, linearity assumption in the financial market variables may be unsatisfactory. Artificial neural network technology is a non-linear mathematical model which is widely applied in the prediction of financial variables due to its flexibility. In this research, a monthly data (1995-2017) for Naira/USD exchange rates were used. Different architectures of the artificial neural networks models were estimated but architectures (3, 6, 1) was chosen because it gives the minimum error rate. This means a network 0f three significant input variables, six hidden nodes and output neuron is chosen for the prediction. It shows that the predicted values compared very with actual values.

309-319

Authors: Akinwumi E. Akinade, Olugbenga A. Falode

The first problem encountered by the reservoir engineer in predicting or interpreting fluid displacement behavior during secondary and enhanced oil recovery project of a stratified reservoir is that of understanding the behaviour or performance of each layer of the stratified reservoir. Accurate prediction of the rate at which fluid can be injected into each layer of stratified reservoir is a key economic variable that must be considered when evaluating a stratified reservoir waterflood project. Each layer’s position and velocity of flood front, time of breakthrough, fluid production rate, waterflood project’s life and consequently, the economic benefits will be directly affected by the rate at which fluid can be injected into each layer of the reservoir. This paper aim at developing a new analytical injectivity model for predicting injection rate into each layer a stratified reservoir introducing the new concept of two-phase (fractional) flow behind the displacement front coupled with physical properties, fluid mobilities ahead and behind the flood front for each layer of the stratified system, Bottom-hole injection pressure, producing well pressure, and average reservoir pressure at the start of injection and flood front advancement in successive layers of the reservoir at a real point in time. The developed model was validated by its application to a stratified reservoir from a particular Niger-Delta Marginal Oilfield and the result was compared against that of 17 years real waterflood injection history performance (data) of the field and that of two existing analytical models. Analysis showed that, the new injection rate model prediction result actually fit with that of the field performance whereas the two existing models with single phase assumption over-predicted the total injectivity of the field which actually confirm the effectiveness of this new analytical injectivity model. Therefore, for accurate prediction of water flood oil recovery from stratified reservoir in Niger-delta oil fields, this new analytical model should be used for accurate estimation of time of water breakthrough, fluid production rate, waterflood project’s life and the economic benefits, this analytical model should be employed to accurately predict each layer’s performance and thereby estimating the total composite reservoir injectivity performance in either homogenous or stratified reservoirs and also valid for performance prediction of Water Injection rate during Pressure Maintenance Operations of Niger-delta oil fields.

324-334

Authors: Shehu A, Danbaba A

Sudoku square designs have been studied under the analysis of variance, but no literature was traced to the Analysis of Covariance of Sudoku square design. This paper proposes inclusion of concomitant variables into existing Sudoku square design models. However, the least square method was used for the derivation of sum of squares and cross products for the various effects of the proposed models as well as analysis of covariance of Sudoku square design.

342-351

Authors: Makia M. Al-Hejuje, Hamid T. Al-Saad, Najah A. Hussain

Surface Sediments were collected from five stations along the Shatt Al-Arab river from December, 2012 to November, 2013 to determine the monthly variation of seven heavy metals (Cd , Cu , Fe , Mn , Ni , Pb and Zn) concentrations and distribution between the exchangeable and residual phases .Results showed that the concentrations of the previous metals in the exchangeable phase of sediments were (7.96, 20.27, 4104.61, 663.18, 75.70, 74.97, 46.33) μg/g-dry weight, respectively, while in the residual phase were (5.12, 23.84, 16381.18, 328.91, 158.94, 30.00, 59.88) μg/g-dry weight, respectively .Enrichment Factors (EF) of the heavy metals in sediment was calculated which ranged from 0.74 to14.05. The low values of EF show that the enrichment of sediment by heavy metals was by natural process, while EF values greater than 1.5 suggest that the sources are more likely to be anthropogenic. Index of geoaccumulation (Igeo) were applied to assess the sediments contamination with heavy metal. According to Igeo values the surface sediments of Shatt Al-Arab river can be classified as unpolluted with Fe and Zn, while unpolluted-moderately polluted with Cu, Mn and Pb, and moderate-strongly polluted with Cd and Ni .

367-376

Authors: Rabab M. Afify, Basem E. Elnaghi, Hamed A. Ibrahim, Sobhy S. Dessouky

Energy saving is one of the most applications. In the industries, Induction motors are the mostly preferred due to their reliability, robustness, price and rugged construction. The largest percentage of consumed energy in industrial is consumed by induction motors. So, Energy conservation in induction motor drive results in the reduction in power consumption and the cost of electricity. This paper describes energy saving technique for squirrel cage induction motor. The energy saving is achieved through managing the voltage administered to the stator winding through the use of the three phase AC voltage controller. The simulation verifications are done in MATLAB/Simulink. The results show that the proposed scheme gives rise to the enormous energy-savings.

386-394

Authors: Zahra’a S. R. Al-Shamsi, Abbas H. Mohammed‎, Hamid T. Al-Saad

This study was carried out to monitoring of Shatt Al-Arab river pollution by assessing the degree of residual heavy metals pollution ‎(Pb, Ni, Cu, Cr, Zn, Co, Cd and Fe) ‎in the sediment samples by using Flame Atomic Absorption Spectrophotometer (FAAS)‎ for sediment core at six stations along Shatt Al-Arab estuary they are: ‎ Al-Qurna, Al-Deer, Al-Qarma, Al-Ashar, Abu-Alkasib and Al-Fao). The degree of Pollution‎ in the sediments had been evaluated by using Contamination factor (CF), Enrichment factor (EF), Geo accumulation index (I-geo), pollution load index ‎‎(PLI),and Anthropogenic Factor (AF).

400-408

Authors: Musah M, Yerima H, Haruna B, Musa A, Umar MT

In this study, activated carbons were prepared from calyx of Gold coast bombax through the two step activation process using sulphuric acid and potassium hydroxide as activating agents. The activated carbons were functionalized using nitric acid. The functionalized carbons were characterized by X-ray defractometer, zetasizer and pH meter. The carbons showed intense x-ray diffraction peaks at 2θ values of 24.67o and 24.47o respectively. pH zero point of charge values of 6.40 and 6.60 were obtained and were lower than pH values of 7.01 and 6.93. Mckay and Poots; and Weber and Morris intraparticle diffusion gave relatively low correlation coefficients. Results indicate the suitability of the functionalized activated carbons in the adsorption of Cr (VI), Mn (II) and Cd (II); and the process is not entirely intraparticle diffusion controlled.

422-428

Authors: T. M. Gwary, H.M. Balami

Geometric symmetry transformation is a mathematical operation that leaves an object, its position and orientation unaltered. The object is any geometrical object which represents a living or non-living organism which can be microscopic or macroscopic particle. Symmetry is a fundamental attribute of nature and environment. The branch of mathematics that describes and represents geometric symmetry in nature, science and society is group theory and in particular Lie group theory. The aim of this article is to state and highlight various geometric symmetry transformations and their application in various domains of science and society. The specific objectives are to study the role of geometric symmetry transformations in physics, chemistry, biology, mathematics and society especially in the arts and the social sciences.

440-445

Authors: Gwary TM, Balami HM

A stable fixed point in a dynamical system is likely to persist in that state, even in the face of minor disturbances or perturbations. It is observed that varying the parameters in a dynamical system evolution function can result in a radical change in systems behavior called a bifurcation [1]. In the case of population dynamics bifurcation is a transition from a fixed population to an oscillation between high and low populations. In this article we will focus on the mathematics of bifurcation in the science of dynamical systems behavior. In particular we discuss the bifurcation behavior of population dynamical system in biology, weather prediction model and chemical reaction system.