DIYALA JOURNAL OF ENGINEERING SCIENCES

The objective of this work is to study the effect of the types of ceramic cutting tools on the cutting performance by using double rake tooling. The simulation in this research concerned with the initial cutting process using contact with the workpiece state. The results show that the concept of double rake tooling design proved to be the cutting performance of cutting process. It is also proved, that for every cutting condition, there is an optimum geometry and material of cutting tool. This work shows that ceramic material of metal cutting tools has better performance from cemented carbide tools comparing with other previously published papers.

The study deals with the hydrotreating of vacuum gas oil with boiling range (611-833K) using trickle bed reactor and a commercial cobalt – molybdenum on alumina as a catalyst with temperature range (583-643K), liquid hourly space velocity range (1.5-3.75 hr-1), hydrogen to oil ratio about 250 lt / lt, and hydrogen pressure kept constant at 3.5 MPa. The results showed that the aromatic content of vacuum gas oil decreased while sulfur removal increased with increasing temperature and decreasing space velocity. The properties, viscosity, density, flash point, and carbon residue of the products are decreased with temperature increasing but the aniline point did the otherwise

The Artificial Neural Networks (ANN) have become a very useful tool in a wide range of engineering applications. In this paper, feed forward neural network Optimal Brain Surgeon (OBS) pruned model is proposed to classify the operating conditions of three phase induction motor. The proposed model had been trained with error back propagation training algorithm using frequency and voltage as input signals with nine possible operating conditions (faulty and healthy) acting as output neurons of the neural network model. The simulation results show that the pruned ANN model can perform perfect classification for the operating conditions of three phase induction motor.

There is a strong interest in the use of aluminum alloy sheet for vehicle applications, particularly the body, where resistance spot welding is the principle joining method. The resistance spot welding (R.S.W) quality has a great effected by the process variable such as, welding current, welding time, and electrode pressure beside other variable such as material thickness and type and electrode diameter. In this work the effect of process variable on welding quality was investigated. Trials were conducted on 1.2 mm thick 2014 – O aluminum alloy sheet. The tensile shear strength was used as primary index of welds quality. Experimental investigation show that the best current is 45 KA, best time is 10 cycle, and electrode pressure of 3 KN.

The main object of this study is to investigate the influence of column diameter and superficial gas velocity on liquid phase dispersion coefficients (axial and radial dispersion coefficients), mixing times, gas holdup, and bubble dynamics (bubble diameter and rise velocity). The liquid phase dispersion, gas holdup, and bubble dynamics (Db and Vb0) were measured for the air-water system in bubble columns of two different diameters,15 and 30 cm. The superficial gas velocity, Ug, was varied in the range 1-10 cm/s, spanning both the homogeneous and heterogeneous flow regimes. The height of liquid in the column was kept constant at 130 cm for the two columns. Axial and radial dispersion coefficients and mixing times were measured at various axial and radial locations inside the columns (Z = 25, 75, 125 cm and r/R = 0, 0.45, 0.85), bubble dynamics were measured at three axial location (Z=25, 75, 125 cm). From the experimental data it was found that, the value of the radial dispersion coefficient (Dr,L) and axial dispersion coefficient (Dax,L), gas holdup, bubble diameter and bubble rise velocity, increase with increasing superficial gas velocity. The results emphasise the significant influence of the column diameter on the hydrodynamics. Gas holdup showed a decrease with increasing column diameter, while the radial dispersion coefficient (Dr,L), axial dispersion coefficient (Dax,L), bubble diameter and bubble rise velocity increased with increasing column diameter. A statistical analysis was performed to get a general correlations for the axial liquid dispersion coefficient as a function of the mixing time and dispersion height (Hd), this correlations are: Dax,L=0.15 H2d /θ0.3 for 30 cm column diameter and Dax,L=0.11 H2d /θ0.3 for 15 cm column diameter.

This paper presents the development of Artificial Neural Network (ANN) model for absorption process of CO2 gas using monoethanolamine (MEA) as a solvent in a falling film reactor. Although studies on ANN applications in chemical engineering in the literature are more concentrated on utilizing dynamic models, there has been an increasing trend for diverse application of ANN to model steady state systems. The feed-forward artificial neural network was adopted and trained by back-propagation algorithm. In this paper 216 sets of data are used to train and test the network. This study shows that ANN model with one hidden layer and nine neurons in the hidden layer gives a very close estimation of the CO2 conversion and there is high potential for absorption application of ANN model.

In this paper an overview is given about laser surface modification process, which is developed especially with the aim of wear resistance improvement. Pulsed Laser was applied to 41Cr4 steel alloy specimens using a Nd: glass laser. Laser processing parameters examined in the present study included power density (3*10^5 to 9.5*10^5 W/cm²). The power density and interaction distance were chosen such that the maximum temperature approaches the melting temperature. The importance of sufficiently high temperatures has already been recognized to reduce the wear rate at the highest power density. The 41Cr4 steel alloy samples were examined using optical microscopic inspection, microhardness test to determine the metallurgical phases and pin-on disc machine was used to estimate wear resistance. It was found in this study the microstructure was relatively dependent of laser power density. However, the laser power density had a significant effect on structural and mechanical properties especially wear resistance in a given power density level.

Nd-Yag (Neodymium Yttrium) pulsed wave laser has been used to modify and refine the surface microstructure of acicular bainitic ductile iron. The wear characteristics evaluated by adhesion and abrasion wear tests while friction characteristics evaluated by using strain gauge technique of the laser processed and unprocessed (as-cast) specimens were studied. The wear resistance and friction coefficient of laser processed samples are significantly enhanced by their refined bainitic microstructures and improved hardness in the melted and resolidified layer. Cross-sectional optical and scanning electron microscope have been used to study the microstructure and wear mechanism of the laser processed and unprocessed surfaces while X-Ray diffraction technique has been used to study and estimate the metallurgical phases. All specimens treated by laser showed wear and friction resistance higher than as-cast specimens at all loads, sliding speeds and sliding times used in this research work.

The control of a rotating single flexible link manipulator and/or a two-coupled flexible link manipulator arm is a highly nonlinear problem. Due to the distributed flexibility. The Mechanical system of a flexible joint two-degree manipulator robot arm has been designed and implemented by using stepper motor, movement axis and External Model Circuit (EMC) for controller. The (EMC) includes Buffer, stepper motor driver and programmable Input/Output. This system is controlled by using two method. The first is Artificial Neural Networks (ANN). The neural network has a feed-forward topology and learning algorithm used Back-Propagation. The second is direct method to supply the program with co-ordinates as positioning data for initializing the robot arm.

The most important activity of metal forming technology is the correct
design of stages geometry for economic consideration in order to increase the metals
utilization coefficient and the productivity realized products with high dimensional accuracy
and a finer quality of worked surface.In this Study the rotation of local coordinate by using
finite element method through (M. S. C / Nastran ) are investigating with influencing of some
parameters such as , Reduction area , Simi die angle and friction factor to obtain the stresses
and strains developed during the drawing process of polygonal section from round section
.The results show that its possible to use the technique of rotation of local Coordinate in all
programs of ( F.E.M ) to analysis metal forming process especially when the friction factor =
0.1 , Simi die angle = 9 o , Reduction area =35% which are gives good agreement to the results
of ( U.B.T )and the practical results

Authentication of a person is an important task in many areas of day-to-day life including electronic commerce, system security and access control. We present Kerberos a client\server authentication protocol which can perform a secure communication over unsecured environments (internet). For example, an e-bank application the client can log on in domain environment using password (single factor authentication) or a smart card running java card application in combine with PIN and the server is the banking hosted system at the bank. Smart card can enhance the security by storing the cryptographic key to perform dual factor authentication, it also can manage the encryption and decryption of the Kerberos keys on it rather then on the client workstation memory. A common methodology depends on the national standardizations is used to evaluate security of that authentication scenarios of Kerberos protocol.

After the expand scope of knowledge and research which become include all fields, lead to the dealing with huge amount of the data and information. Therefore need increased to the developed and technical manner to arrangement this huge expand in volume of the data and information that dealing with the organizations on difference kinds because to continue in these works in success and development, call the information system .Because of the signification of management information systems in achievement the management goals, this demand research on the best manners which help on evaluation these systems in the construction companies, and consider the Analytic Hierarchy process one of these manners .This research Focus on presentation Analytic Hierarchy Process(AHP) as a technique help for making optimum decision through construction of the project which its object complex problems . This research aims to evaluation the management information system relating to controlling and following up on construction costs of projects which performs by construction companies in university of Diyala throughout determination of the used criterions to determination the optimum company from aspect management information system, and determination list to the companies working in the university of Diyala which choose the optimum company from this aspect .In order to satisfied this aim, a data collection have been made from some literatures about Analytic Hierarchy and management information system ,then from the personal interviews with the specialists of designers and constructors in the construction companies .The results of data analysis of samples show that the criterions management , followed manners and systems , data recording , and complete the project planning have obtained a great portion of relative importance comparatively with another criterions between companies .and the criterions management and followed manners and systems are more important than another criterions of the companies .The company of the Ramtha land had obtained a great portion of relative importance comparatively with another
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companies .Finally, it has been resulted to set of conclusions and recommendations for different aspects of this subject, such as , absence the management information system able on ensuring the cost informations wanted in suitable time , and the need to the management manners qualified essential to evaluation construction companies in the different aspects and specially in the field of costs data and informations documentation systems.