Al-Qadisiyah Journal for Engineering Sciences

This paper aims at revealing the effect of the Climatic characteristics on the dust formation in Al-Najaf City through defining the relationships between the Climatic features and anthropogenic activities.
The study revealed the climatic factors in the area of study as temperature, humidity ,rain ,and wind and analyzed their effects on dust concentration at industrial zone in order to determine the environmental impacts for the area of study. The analysis showed the great effect of climate and human activities on dust precipitating on the area of study. Finally, the conclusions and recommendations which help the reducing of the risks of this important problem were presented.

The effect of some protection methods on electrical corrosion resistance of high carbon steel(DIN CK 80) is studied. Electrical coating using chrome and Tin elements were implemented on some specimens to show the effect of this element on corrosion behavior
In addition to use inhibitors and cathodic protection for the same purpose. The potential static method used for corrosion test where electricalcurrent flow through electrical open circuit where the metal represent the cation and platinum represent the anion to determine the potential of the metal and compared it with the metal potential's in electrochemical series closing the circuit and the current flow by increasing the potential +_100 milvolt through the intersection contacts to the cathodic and anodic electrode in accordance with Tafel's method and calculation of corrosion rate.It can be deduced that all methods used contributed in reducing the corrosion rates by different percentages comparing with the base metal .

This paper suggest a proposed algorithm to hide message encoded using "EBCDIC" in multiform DCT's coefficients for two images. The DCT has the property that, for a typical image, most of the visually significant information about the image is concentrated in just a few coefficients of the DCT. Notice that most of the energy is in the upper left corner. Hiding message can be obtained without use original image with high quality. The experiments for embedding and extracting was successfully simulated by MATLAB.

Capacity and level of service are the control points of the analysis of intersections and must be fully considered to evaluate the overall operator of the intersection.
The objectives of the present study include the analysis, evaluation and improvement of the operation for AL-Mustansiriyah Intersection in Baghdad city and to present the best proposal to enhance the performance from the capacity point of view.
To achieve these objectives, the estimated distribution of the traffic data in different directions that required for the traffic and geometrical analysis were gathered manually, while HCS traffic program is used for the requirements of traffic analysis process.
It has been concluded that the flyover between Al-Mustansiriyah University Street –Al-Talibia Street (Proposal No.2) is the best proposal to improve the operation ability of Al-Mustainsiriya roundabout Intersection.

It is well known that power control plays a very important role in CDMA cellular system when mobile subscriber moves in the cell, especially when very close to the border; the realization of power control is practically based on the result of the detection of signal power. So different techniques are analyzed in details such as distributed balancing, distance based and constrained power control. Also Stepwise Optimal Removal Algorithm (SORA) is introduced and evaluated to enhance Carrier to Interference Ratio (CIR) and capacity compared with previous techniques where the outage probability remains relatively low at higher users.

This work investigates a free vibration analysis of plates containing a single crack as the crack parameters (i.e. length , orientation and location) is varied. The influences of these parameters on the natural frequencies and the corresponding mode shapes are examined for several squared simply supported plates including internal crack or edge crack or corner crack. Vibration analysis for these plates is carried out using finite element method through ANSYS package version 11 . The validation results are presented and compared with the most recent numerical results found in literature. It is found from present study that the length of the crack as well as its orientation and location are shown to have significant effects on the natural frequency and mode shape of the plates. Some new cases are also discussed in detail. The study is particularly useful in the understanding and offering a better insight into the free vibration of the plates with various crack configurations.

There are many kinds of wind mills and turbines. In this study, practical rig models of two turbines were manufactured at Nassiriya city (31.036o N, 46.21o E) to compare their work with other related properties and fundamentals. The first is vertical axis wind turbine called Savonius rotor (S- rotor) with dimensions (1500*500*8) mm, the second is horizontal axis wind turbine has a components of plastic blade, steel bearing, steel base, steel shaft, bearings and pointed blade, the plastic blades erected on steel support of length 210 mm. Theoretical analysis of turbines motion were presented in wide manner of explanation. The readings of the two turbines were done in 2nd, 3rd, 8th March and 2nd, 4th April , 2011for many parameters of motion, angular velocity, linear velocity, kinetic energy, air mass flow rate and mechanical power. The results of wind velocity were compared with metriological data in Nassiriya city. The maximum amount of power was 4.65 Watt calculated for horizontal axis turbine. FLUENT and GAMBIT codes were used to prove the validity of this study. It was concluded that the horizontal axis turbine is more efficient than the vertical one, which is in good agreement with literature.

The heat generation during metal cutting processes affects materials properties and the tool wear. Knowledge of the ways in which the cutting conditions effect the temperature distribution is essential for the study of thermal effects on tool life. Analyses of three-dimensional transient temperature distributions in a metal cutting process using a finite element code the Deform 3-D was presented in this paper. The effects of the rake angle, cutting speed, feed rate, tool and workpiece materials on the temperature and heat flux are studied. The results show that increase in cutting speed and feed rate increases the cutting temperature while increasing rake angle reduces the cutting temperature. Results indicated that, as cutting speed increased from 103.2 to 250 m/min an increased in temperature equal to 21.9% occurred. With a reduction in rake angle from 5o to -5o, temperature increased by 12.3%. As the feed rate increases from 0.16 mm/rev to 0.25mm/rev, the temperature increases in a 13.82%.

A relation for predicting the drag coefficient for the process of bubble growing in a convective surrounding (uniformly superheated pure liquids) was developed. The non-dimensional parameters governing the motion and heat transfer are identified and a theoretical study of the effects of the variation of these parameters is made. The drag coefficient decreases with time for all accelerations, as well as with augmentation of the bubble acceleration at each instant of time, independently of the internal vapor parameters for bubble. The theoretical results obtained were agreeable with the previous theoretical data available with error ± 8.80 % % for non-dimensional time τ=1 and within ± 5.4 % for non-dimensional time τ=10.

This paper discuss the natural frequencies and modes shapes of oblate shells by finite element method via ANSYS12 package with and without longitudinal and lateral stiffeners. Different types of elements are considered using three dimensional analysis with APDL program to take the variables of shell’s thickness, number of stiffeners and size of stiffeners. The obtained results reported the tenth structural natural frequencies and mode shapes which are based upon the behavior of the shell, it can be shown that the natural frequency of the oblate shell increased with increasing the mode number and the amplitude decreasing as increasing the thickness of shell.