Journal of Techniques

Sheet hydroforming (SHF) or hydro-mechanical deep drawing (HDD) has been emerged as one of the desirable manufacturing processes particularly in automobile industries. This importance is appeared due to its capability of producing complex mechanical components in few steps. It also presents further advantages such as improved structural strength, stiffness, and more efficient material usage. The SHF depends directly on many factors, and the most important one is a friction. The friction plays an important role in SHF operation processes; therefore, different values of coefficient of friction between the die and sheet were considered in the present paper. These values were varied from 0.01 up to 0.35, and hence the obtained results showed that higher values of coefficient of friction led to a low expansion capabilities and more thickness alteration. This means that the friction between die walls and the employed sheet was increased when a bead force is created a bead force and it is dependent directly on the contacted surfaces and expanded plastic zone. Finally, some preliminary results on the effect of friction on this type of high pressure forming and choosing best working conditions, as well as effect on sheet thickness are presented with some experimental results.

The occurrence of faults during the flight of unmanned air vehicle UAV is a very critical situation that affects the completion of the mission. It was found that these faults are mainly due to failure in the sender (sensor), it was also found that the rate of failure is high in electrical energy Sensors (ac, dc and battery).This research presents an effective technique to ensure that the electrical power system (.ac, dc, battery) or the sensors are faulting free. This technique using two different approaches. The first approach is Radial Basis Function RBF-NN trained with the Extended Minimal Resource Allocation Network - EMRAN algorithms. The second approach, which is presented in this Paper, is based on Knowledge based Neural Network NN based tool SFDIA (Sensor Failure, Detection, Identification and Accommodation problem). Neural Network ANN based tool SFDIA Sensor Failure, Detection, Identification and Accommodation problem, are used to provide analytical redundancy from which residuals are generated, enabling the detection of failures on sensor signals. Upon detection of failure, the faulty signal is replaced by the neural network based estimate. This technique allows the flight to continue within specified performance limitations. The results achieved from the modeling process showed that the neural network based tool SFDIA is able to show high-resolution results in the behavior of electrical energy Sensors (ac, dc and battery).

In this study the GIS was applied with the aid of the spatial analyst extension’s hydrology tools, by using DEM (digital elevation model) to create the watershed and network stream. After delineation the watershed by using GIS, the area value of watershed for Ali al-Garbi water storm was equal to 44211.431 hectare, and the part of this watershed was lied in Iran(Illam governorate) but the major part of the watershed was lied in Iraq (Maysan governorate) .The intersection outlet point of watershed with the Ali al-garbi –Baghdad road, it had the coordinate (657830.15 E, 3595395.16 N), and represents’ the location of suggests culvert.Finally and easily, by using the rational method was estimated the design flood for the culvert was estimated equal to 122.80 m3/sec

Two–dimensionalnumericalsimulation iscarriedouttostudythefundamental characteristicsof compressible flowsthrough double elbow channel, the air used as a working substance. One channelinclude horizontal flow enters first elbow and the other include vertical entrance to the second elbow. In thispaper,theflow fields in two elbows with their dead zone have beeninvestigated.Anon-lineark- Є model isemployed to solve the flow characteristics by using the finiteelementmethodwithacurvilinearcoordinate system near the dead zoneThe k-Є model is a semi-empirical model based on model transport equations for turbulent kinetic energy k and its dissipation rate ε. i.e. the rate at which turbulent kinetic energy is converted into internal energy by viscous action. The derivation of turbulent kinetic energy and its rate of dissipation derived from Navier stocke equation. The model geometry and mesh were created using the COMSOL 3.5 software. This results of the simulations that have been made to date; baseline results employing the k-ε turbulence model are presented, the predicted value for the flow characteristics in double elbow is in reasonably good agreement with published correlations. For accurate solution the computation is considered converged to the steady solution, when the value of the maximal normalized equation residual is less than (10-6). The model applied for two different flow velocities (20m/s) and (30 m/s) and the obtained results presented as curves, surface and contours for velocities turbulent kinetic energy , rate of dissipation of turbulent kinetic energy and vortices .the builded model can be utilized for academic purpose since, it widely used were most flow systems contain elbows.

This paper presents a robust PID neural controller based on particle swarm optimization for a four degree of freedom of half-car active vehicle suspension system .The scheme of the discrete-time PID control structure is based on neural network and tuned the parameters of the robust PID neural controller by using a particle swarm optimization PSO technique as a simple and fast training algorithm.
The robust PID controller is tested at two road profiles, bump and ramp. Simulation results show that the present controller can reduce the peak overshoot and transient period of the displacement, pitch angle acceleration of the vehicle body under different road conditions and vehicle speeds compared to passive suspension system. So the ride comfort and road holding ability will improve during the drive.

A data structure is an arrangement of data in a computer's memory or even disk storage. It is an example of several common data structures as arrays, linked lists, queues, stacks, graphs, and trees. Data structures provide a means to manage huge amounts of data efficiently, such as large databases and internet indexing services. In Non-linear data structure, every data item is attached to several other data items in a way that is specific for reflecting relationships and are not arranged in a sequential structure, like tree and graph data structures.
Computer simulation is the discipline of designing a model of an actual or theoretical physical system then executing the model on a digital computer and analyzing the execution output. The aim of this research is to design non linked data structure simulator to simulate the graph structure like: graph types and representation in memory, and also tree structure operations as traversing methods, tree conversions, building Binary Search Tree (BST) and some of tree applications), because many students find difficulty in understanding various parts of this subject.With the help of this simulator, the user will be able to study and run different operations of the non linear data structure, for each operation there are some examples to show how to do the processes using step by step before executing the process practically on different trees that he(she) can construct by himself. The simulator can tell the student whether the solution is correct or not and give a chance to correct the solution to achieve a better understanding or read more examples for learning. This model can serve as a tool for teaching and helping the student to get an ideas of how a real data analysis is done inside computer.
The simulator is designed with Microsoft Visual Basic 6.0 Programming language which is classified among the object-oriented programming languages to provide a good graphical user interface (GUI) to process the tree functions. The system has been presented on some of the arbitrators in the same field, as well as it is applied in practice on a random sample of students from the second year of the computer system department in Technical Institute of Kirkuk, which proved better understanding for graph and tree data structure and its operations

Wellbore instability represent one of the serious drilling problems encountered in shale formations due to interaction between drilling fluids and shale formations. The investigated Shale samples was taken from Well (K-246) located in Baba Dome in Kirkuk oil field.
Pore pressure transmission experiments were performed to study the effect of variations in wellbore pressure (Pw) with different salt types and concentrations on the wellbore pressure(Pnw) which affect or disturb the state of stresses around the wellbore.
The Invariant Shear Stress (√(J_2 )) profile are calculated to determine wellbore instability state as a function of salt types and concentrations depending on the Mohr-Coulomb failure criterion which is experimentally determined for the shale sample by Tri-axial Test. The results shows that well (K-246) is unstable(Collapse Failure) at (Pw = 2400 psi and 2440 psi) at salt concentration (14% and 16%) for NaCl, KCl and CaCl2 salt solutions but stable for other salt concentrations employed in the research.

The main purpose of this research is to evaluate the effect of maximum size of coarse aggregate (MSCA) on the development of strength (compressive and tensile) of high strength concrete (HSC) and self compacting concrete (SCC) using locally available materials. Two sets of mixes, one for HSC and the other for SCC were prepared. Each set includes three mixes with same materials; fixed mix proportion and different MSCA (20, 14 and 10) mm. Fresh concrete properties were evaluated using slump test for HSC and slump flow, V-funnel and L-box tests for SCC. 72 cubes, 48 cylinders and 48 prisms for determination of cube compressive strength (fcu); splitting tensile strength (fs) and flexural strength (fr) respectively were fabricated from 6 batches. Concrete specimens after (7, 28, 56 and 90) days were investigated. The results indicated that it is possible to produce HSC and SCC with satisfied fresh and hardened properties from locally available materials by using coarse aggregate (CA ) with (20, 14 and 10) mm as maximum size. Based on the results of this work, workability of HSC increased as MSCA increase with using a fixed water to cement ratio and a fixed rate of superplasticizer (SP) while the fresh properties of SCC increased as MSCA reduced with using an optimum SP dosage for each mix. The results showed that fcu, fs and fr for HSC and SCC increased with the decreasing MSCA and observed as maximum at 10 mm MSCA when compared to 20 mm and 14 mm size at all ages of concrete. Based on the results, decreasing MSCA from 20 mm to 10 mm increased fcu by (11-16) %, fs by ( 5-8) % and fr by (6-9) % for HSC and fcu by (8-12)%, fs by (4-7)%, and fr by (5-8) %, for SCC for ages between 7 to 90 days. The results also indicated that the ratios of 7- day to 28- day of fcu values for HSC were higher than that of SCC and there was notable gain in fcu values after 28 days age for all mixes. Hardened HSC & SCC specimens in splitting and flexure showed similar pattern of strength development to those corresponding in compressive strength with a lower rate.

In this paper the effects of hot forging used as a secondary process after powder metallurgy in fabrication of Metal Matrix Composites (MMC’s) was examined. A comprehensive study was made on the mechanical properties of MMCs after hot forging process, when maximum load of hot forging was estimated by FEM simulation (DEFORM-3D software). It was found that most properties are superior as compared to without forging process. Properties including compression strength, flextural strength and hardness were found to be better for most of the MMC’s. The hybrid MMc’s has the best properties compared with respective MMC’s before and after hot forging.

Mercury is one of contaminating elements for environment being a heavy metal that discharged from many chemical industries, such as Al- Furat State Company for Chemical Industries, where it is used as a catalyst in mercury cells to produce caustic soda NaOH, leading to the introduction of some concentrations of mercury with wastewater discharged from the process plant.
The presence of toxic heavy metals in industrial discharge wastewater has become a matter of environmental concern and certainly, these metals have negative side effects on humans and on aquatic ecosystems.
The outcomes of this research showed that the most effective conditions for the efficient removal of mercury from wastewater by using of precipitation and coagulation method are within, pH range (7-8), and ambient temperatures with 1 hour resident time for each precipitation and coagulation processes. The approach of treatment includes only one filtration process at the end of coagulation process.
The dosage of Na2S (the precipitated material) has an effective role for the treatment process, which is characterized as inexpensive and easy.
According to the presented results, an efficiency of (99%) for mercury removing can be achieved by this method

In this work the methodology to evaluation the abrasive wear in closed warm forging die blocks material were manufactured from hot work tool steel H13 in two conditions; unquenched and quenched and tempered (QT).Two hundred flat countersunk head rivet are produced by warm forging operation, 100 forging (rivet) in each die block material.
The wear in die is evaluated by implementing a methodology of measuring the used (worn) dies profile by a coordinate measurement machine CMM, then compensate the predicted plastic deformation die surface by using FEM-simulation code DEFORMTM-2D to separate the captured wear depth in die surface profile. The measured (separated) wear depth is used in Archad’s wear model to estimate the experimental wear coefficient (K) in order to comparing it with the predicted (numerical) wear coefficient (K) from simulation of forging operation. The suggestion of a new wear coefficient (K) to optimizing the forging process, gives the designer a possibility of forecasting the reached wear level.
The numerical results showed a good agreement with experimental where the maximum differences are (12 % and 12.6 %) for unquenched and quenched and tempered die material respectively.

Long Term Evolution (LTE) is a radio platform technology that will permit operators to attain even higher peak throughputs thanevolved High-Speed Packet Access (HSPA+) in higher spectrum bandwidth. Time-domain based channel estimation for orthogonal frequency division multiplexing (OFDM) based Discrete Multiwavelet Transform (DMWT) system with pilot-data multiplexed scheme is investigatedin this work. Starting with the analysis of channel estimation processes, current the Minimum Mean Square Error (MMSE(andLeast Square (LS(estimators and compromising between performances in different Stanford University Interim SUI channel scenarios. The simulation presented by Matlab Simulink results show that MMSE method achieves better BER performance than the (LS (method.

Experimental and numerical study has been conducted to examine forced convection for air flowing through rectangular duct (10 * 12*100 cm) for vertical and horizontal position; the duct was heated at constant heat flux ranging from (0.2 to 0.54kW/m2). The porous materials were packed by plastic sphere with diameter (4cm). The tests were done for Reynolds number ranged (6913-11433).The results showed that Nusselt number increased with increasing Reynolds number and heat flux for both position. Nusselt number in vertical position is higher at (14%) percent than horizontal and highest at (1.1, 0.91) times than empty duct at vertical and horizontal position respectively. Many experimental correlations have obtained.