Volume 2, Issue 5, August 2011
The Problem: Determination of Functional Dependencies between Attributes Relation Scheme in the Relational Data Model
Ignacio Vega-Páez, José Angel Ortega and Georgina G. Pulido
Section of Graduate Studies and Research of ESIME IPN (SEPI ESIME IPN), Zacatenco México, D.F
Department of Basic Sciences and Engineering UAM Azcapotzalco, México, D.F.
Abstract– An alternative definition of the concept is given for “functional dependency” among the attributes of the relational scheme in the Relational Model. This definition is obtained in terms of the set theory. For that which a theorem is demonstrated that establishes equivalence and on the basis theorem, an algorithm is built for the search of the functional dependencies among the attributes. The algorithm is illustrated by a concrete example.
Keywords—Data Scheme, Database, DB, Data Scheme, Functional Dependency and Relational Model
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Inhibition of Copper Corrosion by Acid Extracts of Gnetum Africana and Musa Acuminate Peel
Nkuzinna Ogbonna, Menkiti Matthew. C. and Onukwuli Okechukwu. D.
Department of Chemical Engineering, Nnamdi Azikiwe University Awka, Nigeria
Abstract– The inhibition of copper corrosion by Gnetum africana (GA) and Musa acuminate (MA) peel under various concentrations of HNO3 at different temperatures of 303K and 333K was studied by weight loss method. The inhibition efficiencies of both Gnetum africana and Musa acuminate peel increase with increase in concentration and decrease with increase in temperature and period of immersion. The inhibition efficiency of Gnetum africana was greater than that of Musa acuminate peel for otherwise identical conditions. Values of activation energy of the inhibited corrosion reaction of copper for both Gnetum africana and Musa acuminate peel were greater than the value obtained for the blank. Thermodynamic consideration revealed that adsorption of both inhibitors on copper surface was spontaneous, physically controlled and occurred according to Langmuir adsorption isotherms.
Keywords—Corrosion Inhibitors, Gnetum Africana, Musa Acuminate Peel and Copper
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Finite-Element Simulation of Electrical Discharge Machining (EDM) Process
Ali. Moarrefzadeh
Islamic Azad University, Mahshahr Branch, Mahshahr, Iran
Abstract– Electrical discharge machining (EDM) is one of the most important non-traditional machining processes. The important process parameters in this technique are discharge pulse on time, discharge pulse off time and gap current. The values of these parameters significantly affect such machining outputs as material removal rate and electrodes wear. In this paper, the mathematical relationships between input and output parameters of EDM are established using regression method and the best set of models is chosen. Genetic Algorithm is then used to optimally determine input parameters levels in order to obtain any desired set of outputs. Numerical simulation of process in ANSYS software an for gaining the thermal profile, the effect of parameter variation on temperature field and process optimization are done. The numerical results show the time-dependant distributions of arc pressure, current density, and heat transfer at the workpiece surface are different from presumed Gaussian distributions in previous models.
Keywords—EDM Parameters, Regression Modeling, Optimization, Machining and ANSYS
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Wrinkling in Aluminum Sheet under Bi-Axial Loading using Finite Element Analysis
Jawad Ahmed Jadoon and Irfan A. Manarvi
Department of Mechanical Engineering, HITEC University Taxila, Pakistan
Abstract– Aluminum is becoming the most popular metal in a wide variety of applications in manufacturing of components for airplanes, automobiles, house hold etc. A wide variety of parts are manufactured using aluminum sheet of different alloy composition. Wrinkling of sheet metal is the most undesirable phenomenon in sheet metal forming, drawing, punching and other similar manufacturing processes. The current research is focused on Finite Element Analysis of Aluminum sheet to simulate onset and extent of wrinkling in aluminum sheet, using FE software ANSYS. Based on the results a comparison was drawn between the wrinkling behaviors at varying load values and points of application.
Keywords—Wrinkling, Finite element and Aluminum Sheet
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Numerical and Experimental Optimization of Flow Coefficient in Tubeaxial Fan
Alireza Falahat
Department of Mechanics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran
Abstract– In this study an attempt was made to find the best the best angle of attack and rotational velocity of a flat blade at a fixed hub to tip ratio for a maximum flow coefficient in an axial fan in a steady and turbulent conditions. In this study the blade angles are varied from 30 to 70 degrees and the rotational velocity is varied from 50 to 200 rad/sec for a number of blades from 2 to 6, at a fixed hub to tip ratio. The numerical and experimental results show that, the maximum flow coefficient is achieved at the blade angle of attack of between 45 to 55 degrees when the number of blades was equal to 4 at most rotational velocities. The numerical results show that as the rotational velocity increased, the flow coefficient increased but at very high rotational velocities the flow coefficient remained constant.
Keywords—Angle of Attack, Tubeaxial Fan, Flow Coefficient and Flat Blade
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Wrinkling Prediction of Aluminum 5456-H116 sheet Metals under Uni-Axial and Bi-Axial Loading through FE Simulations
Amer Sattar and Irfan A. Manarvi
Department of Mechanical Engineering, HITEC University, Taxila, Pakistan
Abstract– Wrinkling is one of the most undesirable defects in forming processes, especially when dealing with thin sheets. Methods have to be devised to control the extent of damage. This defect if left un-attended can cause irretrievable loss. Remedial measures include proper constraining of the thin sheet as well as appropriate loading techniques.FEM software can be effectively used not only to predict the extent of damage, but damage control measures can also be simulated to suggest appropriate action to be taken at forming stage. This would drastically cut the cost incurred to remove the “Wrinkles” at later stage. Removal of this defect after the forming process may be not only expensive but sometimes impossible, as has been observed in die making. Present research was focused on using Finite element software to predict the possible remedial measures to be adopted. These results could then be used as reference for carrying out non destructive analysis of this problem, leading to savings in inspection cost, lesser repair time and more focused fault isolation.
Keywords—Finite Element Analysis (FEM), Stress, Displacement, Wrinkles, and Yoshida Test
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Web Application Testing Techniques
Mehwish Nadeem, Amjad Farooq and Fatima Maqbool
Department of Computer Science and Engineering, University of Engineering and Technology, Lahore-Pakistan
Abstract– Testing plays a vital role in the success of an application and it is an important part of the life cycle of an application. A web application can be accessed over a network like internet via different browsers. The ubiquity of web applications and their ability to be updated and maintained without being installed on the client systems increase their demand. The need for efficiently testing the web applications increases as the awareness of complexities encapsulated within these applications grows. In this review paper different testing techniques/methods used to test the web applications are studied and analyzed. The analysis shows how various techniques will be helpful to enhance the system performance and make it more efficient and reliable.
Keywords—Testing Techniques, URLs, Regression Testing, Load Testing and Software Development
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Impact of Employee Satisfaction on Success of Organization: Relation between Customer Experience and Employee Satisfaction
Afshan Naseem,Sadia Ejaz Sheikh and Prof. Khusro P. Malik GPHR
Department of Engineering Management, Centre for Advanced Studies in Engineering, Islamabad, Pakistan
COMSATS Institute of Information Technology, Attock, Pakistan
Abstract– Employee satisfaction is considered weighty when it comes to define organizational success. Employee’s satisfaction is central concern particularly in the service industry. Need to enhance employee satisfaction is critical because it is a key to business success of any organization. In the present milieu, employee satisfaction has come under limelight due to stiff competition where organizations are trying to carve competitive advantage through the human factor. The purpose of this study is to examine the relationship between employee satisfaction and customer satisfaction and to examine the impact of both on organizational success. This study scrutinizes the effects of different factors of organization which affects the employee satisfaction. This is a cohort study in which qualitative research methodology was used. The data was collected through self-administrated questionnaire which contains multiple choice questions and open questions. Results of the principal component analysis (PCA) based on correlation matrix revealed a great deal of employees (hotel workers) satisfaction among surveyed cohorts where customers also had expressed satisfaction with existing services. Mainly environmental cleanliness, quality food and room services has played vital role in creating contentment and subsequent satisfaction among customers. From employee’s perspective, conducive working atmosphere coupled with incentives like salary and frequent trainings focused the employees to work with dedication to uplift the organization (hotels) which is reflected clearly by the satisfaction level of customers. Our study confirms indirect relation between organizational success and employee satisfaction which was mediated by customers. In conclusion, it seems reasonable to believe that understanding of employee role is extremely important as it appears key factor in the success of modern organization.
Keywords—Employee’s Satisfaction, Organizational Success, Customer’s Satisfaction and Job Satisfaction
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Incidence Matrix-Based LMP Calculation: Algorithm and Applications
Mohammad Sadegh Javadi
Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Fars, Iran
Abstract– This paper presents a new approach for calculating Locational Marginal Price (LMP) based on incidence matrix. This approach is an effective tool which can be implemented for short-term and long-term power system analysis, especially for economic analysis of restructured power systems. A DC-Optimal Power Flow (DCOPF) methodology has been considered for LMP calculation. This approach can be applied in market simulation and planning owing to its robustness and speed. Unlike, previous admittance based matrix methodologies, which solidly depended on the network topology, independency of network in the presented approach; it would be an effective tool for long-term expansion planning criteria. The simulation results show that the presented method is both satisfactory and consistent with expectation.
Keywords—Incidence Matrix, Locational Marginal Price, Pricing Mechanism and Power System Economic
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Improvement of Hotel Service Quality: An Empirical Research in Pakistan
Afshan Naseem, Sadia Ejaz and Prof. Khusro P. Malik GPHR
Department of Engineering Management, Centre for Advanced Studies in Engineering, Islamabad, Pakistan1
COMSATS Institute of Information Technology, Attock, Paksitan
Abstract– Service quality is considered substantial when it comes to define organizational success. The winning strategy is to deliver excellent quality service to customers. In the present milieu, need to improve service quality in Pakistan hotel industry have come under limelight due to stiff competition where hotels are trying to carve competitive advantage through the human factor. Excellent quality service not only results in a profit strategy but also it is energizing for employees to perform to their potential to meet challenges. By providing quality service, organizations can sustain customers’ confidence and competitive advantages over their competitors. This study scrutinizes the effects of various elements of hotel industry which affects customer satisfaction. In this research paper, both qualitative and quantitative studies were used. The data was collected through questionnaire which contained multiple choice questions. Results of different correlations, T-test and sequence graphs revealed a great deal of existing services with customer satisfaction. Mainly courtesy of attendants, comfort in guestroom, cleanliness and environment of hotel have played vital role in creating serenity and subsequent contentment among customers. Our study confirms direct relation between organizational success and customer satisfaction. It seems judicious to believe that understanding of customer satisfaction role is extremely significant as it appears key factor in the success of modern organization.
Keywords—Service Quality, Organizational Success, Customer’s Satisfaction and Customer’s Perceptions
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Second Law Analysis of Nanofluid Flow in Coiled Tube under Constant Heat Flux
Alireza Falahat
Department of Mechanics, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran
Abstract– This paper analytically examines the effects of adding nanoparticle on the entropy generation of water–Al2O3 nanofluid flows through a coiled tube under uniform wall heat flux condition in turbulent regime. It is found that adding nanoparticles improves the thermal performance of water-Al2O3 flow with Re numbers less than 40,000. The pumping power to heat transfer rate ratio by adding nanoparticles in constant anddifferent investigated. Moreover optimum conditions (based on the entropy generation sense) for turbulent nanofluid flows are obtained.
Keywords—Coiled Tube, Nanofluid, Optimization and Second Low Analysis
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Developing a New Technique for Face Analysis and Recognition
Hasnain Ahmad, M. J. Arshad and A. Hussain
Department of Computer Science and Engineering, University of Engineering and Technology, Lahore-Pakistan
Abstract– In this research work, a research was done to find out the different approaches to the face recognition problem. It has been observed that these different approaches fall into two major categories that are given below: i) Feather based recognition, which is based on the extraction of the properties of individual organs located on a face such as eyes, nose and mouth, as well as their relationships with each other and ii) Principal component analysis, based on information theory concepts, seek a computational model that best describe a face, by extracting the most relevant information contained in that face. A face recognition system, based on the eigenfaces approach is proposed. Eigenfaces approach seems to be an adequate method to be used in face recognition due to its simplicity, speed and learning capability. Experiments results are given to demonstrate the viability of the proposed face recognition method.
Keywords—Face Recognition, Eigenfaces, Analysis and Developing
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