European Journal of Scientific Research
Volume 142 No 1
Subordination Results for Certain Subclass of Univalent Functions
Waggas Galib Atshan and Khudair O. Hussain
In this paper, we consider
of univalent functions
be the class of
-convex functions of order
, and analogous to the class
we define the class
of univalent functions
then, obtaining some subordination results on functions in this class.
Keywords: univalent function, convex function, γ-convex function, differential subordination.
Hydrofluoric Acid Absorption on Water in the Phosphate Rock Acidulation Process
HR Zea and MD Poveda
The determination of the packet column height necessary for the absorption of HF from a gass stream originated from the phosphate rock acidulation using water as absorbent liquid and plastic raschig rings (50 mm) as packing material was performed. About 99% of the absorption of HF is carried out in the first 0.6 m of packaging, however environmental restriction is so strict that another section of 0.6 m of packaging are required to remove the remaining of 1% HF from the gas phase, similar profiles are observed for the composition of water vapor in the gas phase. The mol fraction composition profile of water vapor in the gas phase has a close relationship with the temperature profile of the gas phase due to the important role the heat transfer phenomena has in in the whole absorption process; water transfer from the liquid phase to the vapor phase is also reflected in the total flow of the gas phase which increases following to the same profile as the observed for th water vapor composition in the gaseous phase.
Keywords: phosphate rock acidulation, HF absorption, non isothermal adiabatic absorption.
The Extent of Utilization of Web-Based Tools By University Students in South-South Zone of Nigeria
Theresa Ofoegbu, Nimitenbo-Ofor J. Harry, Christopher Ibenegbu and Bibian Phil-Eze
The study examined the extent of utilization of web-based tools in Nigerian Universities. A descriptive cross sectional survey research design was used for the study. Two research questions were posed and one hypothesis formulated to guide the study. The population of the study consisted of 35,386 students in federal, state, and private universities in South-South Nigeria. A sample of 395 students was drawn using proportionate stratified sampling technique. The instrument for data collection was a questionnaire which was validated by three experts and internal consistency reliability coefficients determined using cronbach alpha technique. Data was analyzed using mean and standard deviation to answer the research questions, while ANOVA was used to test the hypothesis at 0.05 level of significance. The findings revealed that students in universities in south-south generally utilize web-based tools to a high extent. However male and female students in federal universities utilize web-based tools in content accessibility to a less extent. Male students in State universities utilize web-based tools more than female students in content accessibility, while both male and female students in private universities utilize web-based tools in content accessibility to a high extent more than their counterparts in other South-South Nigerian Universities. The two way ANOVA indicated that there was statistically significant difference between the groups. Based on these findings some recommendations were made, among them are: universities should improve on web-based learning in their teaching programmes and source grants to promote the use of web instructions.
Keywords: Utilization, Web-based Tools, Nigerian Universities, Students.
Exergy Analysis of a MSF-MED Desalination Plant for Optimal Design
Y.Aroussy, M .Nachtane, M.Oulhazzan, M.Tarfaoui and D .Saifaoui
Exergy study is a great diagnostic mechanism in thermal operations performance evaluation. Multi-stage flash (MSF) and multi-effect distillation (MED) are the principal current systems for seawater desalination. We tried in this paper to combine electricity generation with desalination seawater. OCP has adopted a new development strategy which aims to increase production of crude phosphate from 28 to 47 million tons in 2020. The horizon industrial development program of OCP expected to increase water consumption of 73 to 181 million m3/year for its various operations (mining / watering tracks and scrubbing the rock, transport...). Sulfuric acid production units Morocco Phosphorus Jorf Lasfar produce the acid at a concentration of 98.5%, through combustion of sulfur and then a conversion of sulfur dioxide and finally the absorption of sulfur trioxide, the energy supplied by the last step is of the order of 26% of the total energy provided by the method is lost by cooling to seawater, where the design of a project to recover HRS part of this energy and ensure the entire electrical energy required in parallel desalination water sea of Morocco Phosphorus complex .
Keywords: Exergy analysis, Sulphuric acid, Heat Recovery System (HRS), Desalination.
Controlling Students’ Disciplinary Problems in Universities
Dr Angie Ijeoma Oboegbulem, Okagu George Onyejiuwa, Rev. Fr. Dr. Ezikanyi Meltus Sunday, Baptista Chinyere Chigbu, Dr Evelyn Ijeoma Ezepue and Dr Chinwe Enyi
Education needs a calm and quite environment to achieve its purposes and objectives but it seems the disciplinary problems in the Universities have destabilized this fact. To this end, this study examined the management strategies for controlling students’ disciplinary problems in the Universities in South-East zone of Nigeria (N=1,712 University Administrators). Four research questions and one null hypothesis were formulated while a descriptive survey design was adopted in the study. Data was collected using a structured questionnaire which was developed by the researchers and validated by two experts in Educational Administration and Measurement/Evaluation, University of Nigeria, Nsukka. Mean and Standard deviation and t-test statistics were used to analyse the data collected in the study. The results revealed, among others, that there were no significant differences in the mean ratings of male and female on the management strategies for controlling students’ disciplinary problems in Universities. Based on the findings, discussion and recommendation were drawn.
Keywords: Controlling, discipline, disciplinary problems, Universities.
A Finit Volume scheme for Modeling Contaminant Transport and Biodegrdation in a Saturated Porous Media
H.Loukili, S.Alami Kammouri
The present paper describes the numerical demarche for resolution of the problem of transport and biodegradation in a saturated porous media. The Conceptual Model is obtained consisting of a series of advective diffusive reactive transport equations.
The transport equation is approximated by a finite volume scheme whereas biodegradation equations are treated separately as a system of ordinary differential equations using Monod kinetics. Numerical results for biorestoration of a single organic component in a rectangular mesh in a two dimensions space (a simplified aquifer) are presented.
Keywords: Numerical demarche, Transport, Biodegradation, advective-reactive model,Finite volume scheme, TVD Scheme, Monod Kinetics.
Optimizing Internet Based Supply Chain Management Using Multi-Objective Evolutionary Algorithms
Sayed Sayeed Ahmad, Harsh Purohit and Manuj Darbari
Supply chain management is playing a big role in the market and business improvements. Due to widely accepted use of Internet, the strategies behind managing supply chain are required to be updated. This leads to a new dimension of the research in the area. This paper is also an effort in this direction that proposes and implements an approach to optimize two parameters of supply chain management; i.e. Stock of the product and Cumulative Production. The proposed approach may be an effort at the crossroads of Soft Computing and Software Engineering area. It is implemented using MATLAB-Global Optimization Tool Box.
Keywords: Supply Chain Management, Evolutionary Multi-Objective Optimization, Multi-objective Genetic Algorithm, Trade-Off, Stock of the Product, Cumulative Production.
Connecting Rod Linear Structural Analysis Using Half Symmetry
The objective of this present work is to estimate the deflections, modal shapes with frequencies induced in the connecting rod of an engine. The emphasis is on the application of computer aided analysis using finite element concept. The component chosen for analysis is a connecting rod used in numerous situations, most commonly in the engines of automobiles. Connecting rods connect the crankshaft to the pistons and are necessary for the proper functioning of an internal combustion engine. The purpose of a connection rod is to provide fluid movement between pistons and a crankshaft. Connecting rods are widely used in vehicles that are powered by internal combustion. In analysis part the finite element model of connecting rod is created using solid tetrahedron elements, appropriate boundary conditions are applied, material properties are given and loads are applied as per its design, the resultant deformation and frequencies that induced when the body is dynamically subjected obtained are reported and discussed.
Keywords: Static znd dynamic analysis, Connecting rod, deflections.
Linear Fresnel Concentrator with Dual Energy Solar Tracking Application: Seawater Desalination
M. Oulhazzan, M. Nachtane, Y. Aroussy, D. Saifaoui, D. Winninger, M.Rouway
In this paper we present an innovative way for salt water desalination by concentrating solar energy at the Moroccan Sahara. The system used is containing an autonomous and modular micro-concentrator which makes it possible to concentrate the solar radiation with automatic tracking of the sun. A set of mirrors focus sunlight onto a fixed absorber located at a common focal point of the reflectors. The focal point is adjustable and allows connecting different types of absorbers. A photovoltaic panel is used to power the solar tracking system. It is possible with this system, by increasing the number of mirrors, to heat fluids at temperatures from 100° to 200°C. It then becomes possible to store the heat produced in order to compensate for the less sunny days. This paper will examine the use of the hot fluids for sea water desalination.
EES program was written to solve the system of governing equations to simulate the evaporation and condensation processes and the experimental results were used to validate numerical predictions.
Keywords: Linear Fresnel mirror concentrator; solar tracking, seawater desalination
Influence of Gas Ratio on Tribological Properties of Magnetron Sputtered TiZrN Coatings
Kamlesh V. Chauhan, Ashwin D. Patel and Sushant K. Rawal
Titanium zirconium nitride (TiZrN) coatings deposited by magnetron sputtering techniques using argon as inert gas and nitrogen as reactive gas. The sputtering power of titanium (Ti) target and zirconium (Zr) target was kept constant at 275W, whereas nitrogen:argon (N2:Ar) gas ratio was varied 08:32,08:12,10:10,08:02 and 08:00. The evolution of (111) and (200) peaks for TiZrN coatings were observed only when the N2:Ar gas ratio values were 08:12 and 08:00.The structural morphology of TiZrN coatings were done by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Tribological characterisation of TiZrN coatings such as coefficient of friction and wear were studied by pin on disc tribometer.
Keywords: Titanium Zirconium Nitride; TiZrN; Sputtering; Friction; Wear; Tribology.