AL-Rafidain Engineering Journal (AREJ)

In The present work the method of Higher Order Finite Strip, based on Auxiliary Nodular Line (ANL) technique, was utilized to analyze the forced vibration of the Simply Supported Box Girder Bridges with cross intermediate diaphragms, Also to find out the dynamic response under moving vehicles loads by means of Newmark's method which falls within the Implicit Time Integration methods. The Bridge Mass Matrix and the Consistent Mass Matrix was used for both bending and in plane actions. While the Guyan Reduction method was used for reducing the Bridge System Matrix through omitting the Freedom Degrees belonging to the Auxiliary Nodular Line for both bending and in plane actions, In order to enable the Higher Order Finite Strip method for analyzing the box girder with cross intermediate diaphragms. vehicle model were used in the analysis is the Moving Force (MF) where the vehicle represents a no. of moving force with a value equal to the weight of the vehicle wheel.

A reliable technique has been proposed to generate a real time pulse width modulation (PWM) signals in order to drive three – single phase uninterruptible power supply (UPS). The PWM patterns have been generated using field programmable gate array (FPGA) and based on selective harmonic elimination method. These patterns are used to drive the six of switching power transistors of the voltage source inverter to produce three – single phase UPS. In order to solve the problem of the complexity of the nonlinear transcendental equations, an intermediate steps have been taken, using artificial neural network (ANN). This will overcome the problem of the off line solution and therefore obtaining the required data to solve the obstacle solution from off line to on line. Therefore, the trained ANN is implemented in a parallel hardware by using FPGA. The benefits of using FPGA to perform ANN are promising and the technique becomes very attractive. It allows a real time, simple, fast, reliable and efficient design with low hardware costs. Finally generating selective harmonic elimination pulse width modulation (SHEPWM) patterns as a real time signals are become visible

The research aims at studying the structural behavior of R.C beams having openings (at the shear zone) under repeated loads. The experimental program includes testing 7 R.C beams of (200mm*350mm*2400mm). The beams were divided in to two groups, the 1st. group were used to find out the shape effect, while the 2nd. group was utilized to find out the effect of the opening size (two beams without openings, considered as a reference beams) group one consisted of three R.C beams either with circular openings (dia.150)mm or square opening (133*133)mm or rectangular opening (200*88)mm located in the middle of the shear zone. Group two, consisted of three R.C beams with variable sizes of circular openings ,that is , (100mm , 125mm , 150mm) diameter ..When the results were analyzed , it was noticed that the presence of openings in the beams caused a reduction in the R.C beams strength a mounting to a ratio between (14-50)%, and caused an increase in the deflection of (25.5-39.2)%(relative to the control beam without openings) depending on the shape and size of the opening. From the study of the shape effect, it was found that the beams with rectangular openings had a higher strength than the ones with square openings of (20.4)% and (38.77)% than those of circular openings. When testing three R.C beams with different circular openings , (100mm , 125mm , 150mm ) diameter , the results indicated ,that the beam of 150mm diameter opening suffered a reduction in strength of (50.5)% while the reduction was (23%)and (14%) for the beams with (125mm)diameter and (100mm) diameter respectively .

Nonlinear loads absorb reactive power and produce harmonics. The demand of reactive power and harmonics cancellation are usually met by employing passive and active power filters. In this paper, a new active power filter topology is suggested in order to improve the power quality on both sides of the HVDC transmission system. A modified harmonics pulse width modulation (MHPWM) control strategy of the new active power filter is presented in this paper. The goal of the modified controller is to enhance the fundamental supply current of the HVDC converters and reduce the total harmonic distortion as lower as possible. The methodology to generate MHPWM signals is based on harmonics error current as reference signal and a triangle wave as carrier signal. Simulation results using Matlab/Simulink show that the suggested active filter is effective for transient and steady-state operating conditions. Therefore PWM pulses simulated by Matlab/Simulink are compared with the Matlab/System generator (SysGen) black box and done experimentally by the Xilinx Field Programmable Gate Array (FPGA). The VHDL codes used in the design process of the MHPWM is implemented firstly in Matlab/SysGen black box and secondly in the Xilinx FPGA Spartan3. These results show that the suggested MHPWM technique for modified active power filter is effectively closed to each other.

Linear Quadratic Regulator (LQR) is one of the most interesting control techniques adopted as a control strategy in state feedback. These types of techniques achieve good results but suffer from the problem of trial and error involved in the computation of weight matrices. The trial and error technique leads to hard tuning of the LQR controller parameters. This of course will lead to difficulty in reaching the optimal system performance.
The paper attempts to solve the above difficulty via the selection of the LQR weight matrices using Genetic Algorithm GA. This proposed solution will avoid the trail and error involved in the state feedback technique. The proposed solution has been adopted in the design of position controller of a robot arm and the results of computer simulation have shown that the proposed solution fulfill specifications, for minimum overshoot , settling and rising times.

The estimation of sediment yields from watersheds is an important factor in studies, design and operation of hydraulic structures. Due to the rare of measured values of runoff and sediments load, the Water Erosion Prediction Project (WEPP) which is work under the Geographical Information System (GIS) to be GeoWEPP was applied to estimate the runoff, sediment load and sediment concentration that enters the Mosul DamReservoir from the western bank. Mosul Dam located on Tigris River, north of Iraq which is one of the biggest multi purposes dam for irrigation, power generation, and flood control. The runoff and sediment loads are estimated for the years 1994-2012 based on daily data of rainfall depth of the Mosul Dam Station.
The estimated average sediment load for the considered period were, 17.4, 1.5 and 1.1*103 Tons for the three mainly basins Swedy, Carnold and Al-Salam respectively. This mean that the total sediment load entered the reservoir for the for the considered period is 380*103 ton, while the volume of this sediments is 317*103 m3 if we considered that all the sediment deposits in the reservoir with trap efficiency 100%.

Quantum Key Distribution QKD mechanism is based on the principles of quantum mechanics to guarantee the secure exchange of secret keys between users. In this paper, the BB84 protocol is simulated, and the enhancement of the protocol using multi-parity instead of single parity is introduced with the error correction unit. The sub-block length is changed dynamically in an adaptive way and according to the QBER values, also this study takes into account the channel effect on the protocol by applying four types of channels (perfect channel, low noise channel, medium noise channel and high noise channel) and all channels are assumed to be lossless. The study includes also the effect of three types of attacks (PNS, IR, PNS & IR attacks) onto the protocol performance. The simulation results show that (IR) attack have the strongest effect on the BB84 performance.

The present research aims to estimate the amount of surface runoff and runoff coefficient in Tel-Abta area west of the province of Nineveh for the purpose of designing and management of small scale rainwater harvesting systems. Daily rainfall data at Tel-Abta for the period (1991 – 2062) are used. The mean annual rainfall for this period is
611 mm. Two computer codes, using EXCEL Programming are developed; one is based on the SCS Curve Number Method "SCS- CN" and the other one is based on the method of Threshold Rain "TR". The study revealed that the TR method resulted in average annual amounts of surface runoff greater than that of the SCS method (23 mm versus 16 mm; respectively). On average, the runoff coefficient at Tel- Abta is in the range of 0.062 to 0.24. Finally, simple equations were proposed to estimate, at Tel Abta area, the runoff coefficient depending on the characteristics of the monthly rainfall in the study area.

In this study, the (Linacre) mathematical Pilot model was used to estimate evaporation from free water surface and test the results accuracy of the mathematical evaporation model by comparing it with the values of the measured pan evaporation class (A) at the Mosul dam reservoir. The daily measured temperature data recorded in meteorological station at the Mosul dam reservoir for the period (2003-2006) were used in addition to the calculated dew point temperature from the values of measured temperature and relative humidity to verify the accuracy of the mathematical model in estimating the evaporation from the Mosul dam reservoir northern of Iraq. Statistical tests showed that this model gives a reasonable results. The accuracy of the model is best for the monthly rate evaporation prediction (E1), followed by the rate of ten days and then daily, with coefficient of determination (R2) are (95%) and (93%) and (87%), respectively. The percent errors in the model prediction (E1) are (6.5%) and (6.1%) and (5%) for daily, ten days and monthly prediction respectively. Since the (Linacre) model require very few data (air temperature only), it can be used to overcome the difficulty of lack of the meteorological data.

Multiple access interference is a major limiting factor for the WiMAX based Mesh Network (WMN) performance. A backbone model equipped with directional antenna for WMN with two routing tree construction algorithms, Paralleled (Para-RTC) and Balanced-Paralleled (Bala-Para-RTC) are proposed here in conjunction with fair centralized scheduling algorithm and efficient link selection criteria in certain time slot, this is an important task to minimize the effect of secondary interferences for a WMN. The use of directivity with these routing algorithms increases concurrent transmissions by making use of spatial reuse, this will result in higher system performance in terms of schedule length and Channel Utilization Ratio CUR. The results also show, that using the Para and Bala-Para RTC algorithms, without directivity, will give CURs of 15.4% and 14.3% respectively, (i.e an improvement of 3.6% & 2.5% over the 11.8% CUR). When the standard Breadth First tree routing BFT is used), and with directivity it will give the same CUR of 18.2%, (i.e an improvement of 2.8% relative to the 15.4% CUR when the BFT is used).

This study deals with the effect of some operational parameters on the removal efficiency and behavior of duckweed based wastewater stabilization ponds. The results of the study showed that; covering the oxidation ponds with duckweed improve their ability to treat higher organic and nitrogenous loads. In addition, there is a relationship among the hydraulic detention time and each of the removal efficiency of organic and nutrients. Decreasing the hydraulic detention time decreases the removal efficiency of organic. On the other hand, the results of research also showed that; increasing nitrogen and phosphor load leads to decrease removal efficiency of nitrate, nitrite, and phosphate, and increases removal efficiency of ammonia. Temperatures have also impact on the organic and nutrients removal and the concentration of dissolved oxygen in effluent. Highest removal and dissolved oxygen concentrations were recorded at the temperature of (26°C), and these values decrease with increasing or decreasing the temperatures.

This paper reports experimental data on the behavior and strength of high-strength concrete deep beams reinforced with shear reinforcement. Tests were conducted on eight reinforced concrete deep beams with stirrups in different type and positions using high-strength concrete (compressive strength of about 85.0 MPa). The beams measured 1400 mm long, 100 mm wide and 300 mm deep, and were tested under two point loads. The test variables were type and position of web reinforcements [Shear stress of vertical stirrups (vfy), Shear stress of horizontal stirrups (hfy) and Shear stress of inclined stirrups (αfy)] within shear span, within middle span(between two point loads) and along the beam. Conventional steel bars were used as longitudinal reinforcement in this investigation. The test results indicated that beams with vertical and inclined shear reinforcement within the shear span (B4) resisting the ultimate load of about 417.90kN. While beams with horizontal shear reinforcement (B3), shear reinforcement between two point loads (B7), and the beam without shear reinforcement (B8) resisting, 7..522,
762.18 and 7.25..kN respectively. All the beams failed in shear and the optimum position of stirrups is the shear span for high strength concrete deep beams and with combination of vertical and inclined stirrups.

In recent decades, new design methods have emerged in architectural domain depending on the computer as a design tool. The ill-defined nature of architectural problem and the designer subjective preferences have required the use of objective methods of knowledge analysis such as exploration. Previous studies on design computing have described exploration in relation to varied design operations; the most important of them are the search and evaluation processes.
The paper puts forward a theoretical framework for exploration in design computing which is able to differentiate the use of exploration among various computational tools. It defines the aims of exploration, the roles of exploration in a design process, the sequence of exploration activities in a design process, and the executor of exploration. The roles of exploration include searching both the design problem space and design solution space; whereas in the latter, exploration is a tool of generating and evaluating design alternatives. The framework is used to identify the tasks of exploration in some design computing tools

The main objective of the present experimental program is to study the behavior of reinforced concrete short columns subjected to combined axial load and flexure strengthened with ferrocement. To carry out the investigation, seven columns were tested. Out of which, one is the control un-strengthened column tested to failure to find out their load carrying capacity, six columns strengthened with ferrocement. The main objective of the present work is to investigate the effects of ferrocement thickness and number of wire meshes on the load capacity of those columns.
Increasing wire mesh layers from 2 to 5 causes an increase in the ultimate load of the strengthened column with ferrocement compared with the control column. Using 20mm ferrocement thickness with a 5-wire mesh layers, the ultimate load increases 36.8% when compared with the control column. Similarly, for 30mm ferrocement thickness with 5 wire mesh layers the increase is 48%.

Reactive powder concrete (RPC) is a special type of concrete, it is rather a mortar than an actual concrete mixture, because traditional coarse and fine aggregate are replaced by very fine sand with particle size in range of (150-400)μm.
In the present experimental investigation, compressive strength, splitting tensile strength and flexural strength of plain reactive powder concrete and reactive powder concrete reinforced with 1% and 2% steel fiber are compared, by using local available material and curing in 20°C and 80°C, and the experimental study was curried out on a two sets of samples. Each set consisted of (54) cubes of (50×50×50mm), (18) cylinder of (100×200mm) and (18) prism of (50×50×300mm). The results show that the maximum compressive strength is 74 MPa with 2% steel fiber and curing in 20°C. The addition of steel fiber by 1% and 2%increased the compressive strength, splitting tensile strength and flexural strength.

The aim of this study is to investigate and demonstrate the use of remote sensing and geographic information system (GIS) techniques to create a thematic assessment in order to locate a best dam site in Al-Tharthar basin northern Iraq. Automated derivation of multi thematic layers to describe the characteristics of the catchment was performed with aid of several softwares (Erdas 9.1, Arc GIS 9.3, Global Mapper 11 and Surfer 9). Gathering all these data has to construct database of the catchment area to decide the locations of the proposed dams. Three locations were chosen. Dam site one was chosen to be the best site since it is provide lesser length with more lake storage and has substantial of foundation material for dam construction. Furthermore, various calculation regarding the design of the dam, its parameters was investigated.

The paper deals with the experimental investigation to crushing collapse behaviour of thin-walled mild steel L-shaped structural under compressive axial load. The aim of this paper is to show that the increase of plastic region will be on the account of elastic region for L-steel plates under compressive axial load by using heat treatment (Tempering). The result has shown a decrease in elastic region with an increase in plastic region during crushing L- steel plates which caused an increase in absorbing energy. Details of the deformation processes were examined by using theoretical, experimental and three-dimensional finite element models. The effect of heat treatment processes were presented to increase plastic region with absorbing energy during crushing plates, Heat treatment is a very useful process to improve absorbing energy with decreasing size of plates. Static load-deformation curves were compared with those obtained from theoretical model based on perfect plasticity and finite element simulations using nonlinear ANSYS program and obtained by quasi-static tests. Conclusions have been given concerning the agreement between the results of finite element simulations and the static once

An experiment study on removal of organics by using Fenton's reagents has been introduced. The effect of operating conditions such as pH, reaction time, H2O2 to Fe(II) ratio (W/W), on the efficiency of Fenton process was investigated. The monitored sample taken from wastewater of Ibn Al-Atheer Hospital in Mosul city, has its concentrations of COD and BOD5, about 663 and 150 mg/l respectively. The oxidation of organic materials in the wastewater is pH dependent and the optimum pH was 3.0. The favorable H2O2:Fe(II) ratio was 1.2:1, and the COD removal rate increased with the increase of Fenton dosage at the favorable H2O2:Fe(II) ratio. The removal efficiency of COD became 93% and improved the biodegradability of wastewater from 0.226 of influent to 0.618 of effluent.