Journal of Techniques

Water supply facility is the first service in the city, adjacent to the human being and its different activities, the problem lies in the lack of indicators of a real, clear mobility in line with the global challenges, climatic, demographic, social, causing the decreasing of efficiency service, including the increase in the proportion of loss which sometimes in the study area may reach to more than (40%) with its fluctuation during the research period (1993-2010) while increase for the period after 2003. From this point of view the importance of the research appear in diagnosis of the factors affecting the loss of water to be within the standards and global indicators. we have found to identify indicator of loss with the development through the adoption of criteria indicators and clear the adoption of water data base consistent with the automation of the joints work and rings for different adoption of the water demand policy follow the accurate water measurement consumption method, away from the estimation method by guessing with the activation and update the laws, regulations, legislation and administrative control strict technical solutions in addition to another task.

Statistical Analysis was achieved by using Paired Samples T- Test to compare physical and chemical properties of raw water and treated water of Al-Tyarra water supply of the year ( 2010) . The water quality of the treated water were checked according to W.H.O., Iraqi, U.S.E.P.A., and the European Union standards of drinking water . The results indicated there were significant differences between raw water and treated water at ( 0.05 ) level of significance for turbidity , hardness, magnesium, and dissolved solids , but there were no significant differences at (0.05) level of significance for alkalinity , PH , calcium , and sulphate, also , the results of the treatment plant shows the flowing : 1- the treatment plant has very good efficiency to remove turbidity and calcium. 2- It has intermediate efficiency to remove alkalinity .3- It has unacceptable efficiency to remove hardness , magnesium , sulphate , and dissolved solids .

This paper presents a classification of grounding system in electric network of Diyala government compared with standard systems ( IEC ) and ( NEC ) , then it show the effect of grounding on improvement of performance and protection in electrical systems in addition to protection of persons from electric shock , all these are tested through practical experimental that represented by measure the resistance of grounding for some electric substations in ( Baquba , Alkhalis , and Almuqdadiya ) cities.
It also includes a study of some types and methods of neutral point grounding ( N ) in electrical networks that is used to reduction of earth fault current , then a study of accredited international grounding systems in this networks , all these studies are investigated to give recommendation and depend on the better types and more accordant for present distribution system .

The ideal system design and efficient irrigation management requires a detailed knowledge and accurate assessment of the soil infiltration characteristics because it is the first and most important step in the design of irrigation systems, especially the furrow irrigation system. The current study searched in the affect of the flow rate in furrow irrigation on the infiltration rate. where several experiments conducted in a rural area on level furrow of (30m) length in silty loam soil with three different flow rates of (0.5, 1, 1.5) L/ s respectively, water phase advance is recorded with equal distances of 5m with time is recorded then the inflow outflow method is used to measure the intake rate and accumulated intake rate functions for the three flow rates. The results show the influence of flow rate on the advance of water in the furrow and also on the intake rate functions. When testing the validity of some known infiltration equations, it is concluded that the original Kostiakofe equation is the best one among types and followed by Horton equation and developed Kostiakofe equation.
Key words: Infiltration, Intake rate, Furrow irrigation

This paper present, the design and simulation of multi rate decimation filter to work with wireless mobile system under software defined radio (SDR) technology. The decimation filter is designed with three stages of decimation filter that consists of Cascaded Integrated Comb (CIC) decimation filter, Compensating Finite Impulse Response (CFIR) filter and Programmable Finite Impulse Response (PFIR) filter. The three cascaded filters could operate to reduce the intermediate frequency from 100MHz to 100 KHz baseband signal in order to more processing. System Generator offers the multiplier less Multiply-Accumulate (MAC) Finite Impulse Response block which reduce the implementation area. The three filters are designed and simulated using MATLAB and verified with System Generator design from Xilinx. Results obtained from the simulations and verification of this design, has shown that the proposed algorithm reduces the error to 2x10-4 between MATLAB design and System generator. The techniques used are promising, and also develops the sample rate conversion of current wireless systems and new generation of wireless communication system up to 100MHz in IF band.

This paper presents a comparative analysis of 3-phase permanent magnet brushless dc motor drive having slightly different phase-emf waveform. Permanent magnet brushless dc motors of 12-slot/10-pole and 6-slot/4-pole are considered in this project. Both brushless dc motors have a permanent magnet surface-mounted rotor, and the stator windings employ single-tooth wound coils such that the phase-emf is trapezoidal. Therefore, both motors are conducive for rectangular-shaped stator phase current excitation in order to produce constant torque output. The mathematical model for BLDC operation and individual definition of the system blocks will be described. The model is later simulated in MATLAB/Simulink version 8. The generated 12-slot/10-pole and 6-slot/4-pole phase-emf data from finite element analysis are used in the Simulink blocks to examine the dynamic performance of both permanent magnet motors.

In this paper, Face recognition system are analyzed and classified based on a new approach, Stationary Wavelet and Neural Network (NN). In this method, the resulting coefficients were computed by the proposed stationary wavelet transform for single-level decomposition. The low pass sub bands of the upper left corner are considered in the proposed method as a resemblance and a smaller version of the original image. The NN of low coefficients is obtained. This method gave an excellent result for a database of 400 different images which indicate that the suggested algorithm is an excellent tool to process the database of standard pose of image. The algorithm is implemented using MATLAB programming languages version R2011a

A low cost house model with a certain spatial scale was constructed in order to inspect its performance against the hot weather of summer season in Iraq. The materials used are wood and aluminum with a small glass window on each side. The natural ventilation, that was applied in order to decrease the inside temperature, made use of the damp ground of the outside park. The ventilation was speeded up using a solar collector which was also a low cost constructed collector that uses empty soft drink cans coated with a special dye.
The experiment was made in July between 9:00 to 15:00 in order to ensure high ambient temperature. Results obtained showed a maximum difference of 10ᵒC between ambient and inside temperature which is accepted considering no air conditioning devices were used with so limited air steam flowing through the inside space of house model.

This paper investigates a new precoding approach in transmit-antenna and path-correlated channels to the adaptation for the Worldwide Interoperability for Microwave Access (WiMAX) baseband, in the physical layer performance of multi-antenna techniques, All cases are based on the IEEE 802.16d standard using orthogonal frequency division multiplexing (OFDM) based discrete multiwavelet transform (DMWT) and quadrature phase shift keying (QPSK) ¾ of coding rates. The proposed Tomlinson-Harashima Precoding (THP) in WiMAX baseband consider a new way and only requires the statistical knowledge of the channel at the transmitter, which significantly reduces the feedback requirements. Both linear and non-linear precoders amend the system bit error rate in transmit-antenna and path-correlated channels. The proposed non-linear precoder THP in closed loop design achieved much lower bit error rates, increased signal-to-noise power ratio (SNR) than linear precoder.

A meaningful analysis of Cylindrical tanks of variable thickness requires an analytical model and dealing with advanced mathematical procedures which may constitute a barrier or dis advantage to the design engineer in dealing with such problems.
This paper is aimed and to present a parametric study of open cylindrical tanks of linearly changing wall thickness with geometrical variables, in the form of wall slope (), wall height (H) and radians to wall height (a/H).
On using Bending Theory of Cylindrical Shells the G.D.E is solved to obtain the maximum values of internal forces leading to bending moment (Mx), the hoop (N) and the radial deflection (Wx). The results are summarized in very simple curves, and are tested for solving practical problems. The curves are seemed to be very handy at the least in the preliminary design of Cylindrical reinforced concrete tank.

Series compensated power system may lead to a very unusual problem known as SubSynchronous Resonance (SSR) which adversely affects the system stability and under certain operating conditions may result in fatigue breakdown of the turbine – generator shafts. This paper investigates the effects of variation of percentage of series compensation of the transmission line reactance on the excited subsynchronous resonance modes in power transmission system, and these excited modes are calculated for different values of compensation after a three- cycle, three- phase to ground fault incidence at bus bar (B2) of the power system which has been modeled and simulated in Mat-lab/Simulink software.

The objective of this paper is to study the effect of pipeline length on the thermal performance of split air conditioning with cooling capacity of 2 TR, which was used to cool a special room of 3*4*2.8m, insulated internally by insulation layer made of Polystyrene. Three lengths of pipeline 3,4 and 5m were used for compression of thermal performance, pressure gauges and thermocouples are used at identified locations, in each of entrance and exit of( condenser, evaporator, capillary tube and compressor), the period of system operation was limited until the difference between indoor and outdoor temperatures reached 10oC. The results show that the pipeline length of 3m gives the best results in term of thermal performance which higher than thermal performance (COP) of pipeline 5m by 15%.

This paper presents the design and simulation of the Digital Up Converter (DUC) in system generator. DUC is a digital circuit which generating digital Intermediate Frequency (IF) signal from low complex digital baseband signal. The DUC provides pulse shaping, interpolation and frequency translation where the up-sampled signal is shifted from centered frequency (2.166 MHz) to intermediate frequency. Due to Wideband Global System Mobile (GSM) specifications, the DUC is to pulse shaped and up sampled the baseband signal by a factor of 16. The DUC up sampled the signal up to 69.333MHz.