Journal of Engineering

The aim of this research is to adopt a close range photogrammetric approach to evaluate the pavement surface condition, and compare the results with visual measurements. This research is carried out on the road of Baghdad University campus in AL-Jaderiyiah for evaluating the scaling,
surface texture for Portland cement concrete and rutting, surface texture for asphalt concrete pavement. Eighty five stereo images of pavement distresses were captured perpendicular to the surface using a DSLR camera. Photogrammetric process was carried out by using ERDAS IMAGINE V.8.4. The results were modeled by using a relationship between the photogrammetric and visual techniques and selected the highest coefficient of determination (R2). The first technique is efficient in evaluating the rutting with (R2) range between (0.985-0.997), (R2) for the scaling range between(0.990–0.999),as compared to the visual evaluation. The macrotexture of the asphalt concrete with a high (R2) range between (0.982-0.999) and (R2) for the cement concrete pavement surface texture range between (0.980 - 0.998), as compared to the sand patch method.

In this study, two types of mixes were adopted by using two grading of coarse aggregate.
The practical side of this study was to produce no-fine aggregate concrete by using crushed clay
brick aggregates. The durability of the produced concrete and internal sulfate attack was studied.
For durability assessment, it is found that the no-fine concrete made with crushed brick
aggregate lost about (15-25) % of its compressive strength after being subjected to 60 cycles of
wetting and drying with age 120 days. The curing condition showed that the water curing
improved the compressive strength with a rate higher than that when sealed or air dry curing
were used. The crushed brick no-fine concrete deteriorated in compressive strength after
exposure to internal sulfate attack for 60 cycles; the percentage decrease was about (23.33-25)
and (25-27.5) % for 0.57 and 0.83sulfate content respectively.

This thesis aims to study the effect of addition polymer materials on mechanical properties of self-compacting concrete, and also to assess the influence of petroleum products (kerosene and gas oil) on mechanical properties of polymer modified self-compacting concrete (PMSCC) after different exposure periods of (30 ,60 ,90 ,and 180 days).
Two type of curing are used; 28 days in water for SCC and 2 days in water followed 26 days in air for PMSCC.
The test results show that the PMSCC (15% P/C ratio) which is exposed to oil products recorded a lower deterioration in compressive strength's values than reference concrete. The percentages of reduction in compressive strength values of PMSCC (15% P/C ratio) was (6.03%) and (9.61%) up to 180 days of exposure to kerosene and gas oil respectively, relative to the same mix immersed in water, while the percentages of reduction in compressive strength values of SCC (reference concrete) was (21.18%) and (25.19%) up to 180 days of exposure to kerosene and gas oil respectively, relative to the same mix immersed in water.
Flexural strength results present improvement for all ages and for all concrete mixes with all percentages of polymer content.
The total water absorption values of PMSCC (15% P/C ratio) showed a better performance than reference concrete mix when exposed to oil products. It was (1.34, 2.21, 2.17) % up to 180 days with samples immersed in water, kerosene, and gas oil respectively, with percentages of reduction of (23.86%), (33.83%), and (31.33%) relative to the SCC (reference concrete).

In this study, the effect of the combination of micro steel fibers and additives (calcium hydroxide and sodium carbonate) on the size of cracks formation and healing them were investigated. This study aims to apply the use of self-healing phenomenon to repair cracks and to enhance the service life of the concrete structures. Micro steel fibers straight type were used in this research with 0.2% and 0.4% by volume of concrete. A weight of 20 and 30 kg/m3 of Ca(OH)2 and 2 and 3 kg/m3 of Na2CO3 were used as a partial cement replacement. The results confirm that the concrete cracks were significantly self-healed up to 30 days re-curing. Cracks width up to 0.2 mm were completely self-healed after re-curing for 90 days by using the combination of micro steel fiber of 0.4% by volume of concrete and 25 kg/m3 of Ca(OH)2 and 2.5 kg/m3 of Na2CO3 as a partial replacement of cement. Products of Self-healing are observed by Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX). It was found that self-healing occurred mainly due to precipitation of calcium carbonate.

Production of fatty acid esters (biodiesel) from oleic acid and 2-ethylhexanol using sulfated zirconia as solid catalyst for the production of biodiesel was investigated in this work.
The parameters studied were temperature of reaction (100 to 130°C), molar ratio of alcohol to free fatty acid (1:1 to 3:1), concentration of catalyst (0.5 to 3%wt), mixing speed (500 to 900 rpm) and types of sulfated zirconia (i.e modified, commercial, prepared catalyst according to literature and reused catalyst). The results show the best conversion to biodiesel was 97.74% at conditions of 130°C, 3:1, 2wt% and 650 rpm using modified catalyst respectively. Also, modified catalyst gave identical results to that of commercial one. Simulation study was adopted from basic principles of reactive distillation and the results were close to an acceptable degree.

Using the Neural network as a type of associative memory will be introduced in this paper through the problem of mobile position estimation where mobile estimate its location depending on the signal strength reach to it from several around base stations where the neural network can be implemented inside the mobile. Traditional methods of time of arrival (TOA) and received signal strength (RSS) are used and compared with two analytical methods, optimal positioning method and average positioning method. The data that are used for training are ideal since they can be obtained based on geometry of CDMA cell topology. The test of the two methods TOA and RSS take many cases through a nonlinear path that MS can move through that region. The results show that the neural network has good performance compared with two other analytical methods which are average positioning method and optimal positioning method.

Energy efficiency is a significant aspect in designing robust routing protocols for wireless sensor networks (WSNs). A reliable routing protocol has to be energy efficient and adaptive to the network size. To achieve high energy conservation and data aggregation, there are two major techniques, clusters and chains. In clustering technique, sensor networks are often divided into non-overlapping subsets called clusters. In chain technique, sensor nodes will be connected with the closest two neighbors, starting with the farthest node from the base station till the closest node to the base station. Each technique has its own advantages and disadvantages which motivate some researchers to come up with a hybrid routing algorithm that combines the full advantages of both cluster and chain techniques such as CCM (Chain-Cluster based Mixed routing). In this paper, introduce a routing algorithm relying on CCM algorithm called (Enhanced Chain-Cluster based Mixed routing) algorithm E-CCM. Simulation results show that E-CCM algorithm improves the performance of CCM algorithm in terms of three performance metrics which are: energy consumption, network lifetime, and (FND and LND). MATLAB program is used to develop and test the simulation process in a computer with the following specifications: windows 7 (32-operating system), core i5, RAM 4 GB, hard 512 GB.

This paper presents a computer simulation model of a thermally activated roof (TAR) to cool a room using cool water from a wet cooling tower. Modeling was achieved using a simplified 1-D resistance-capacitance thermal network (RC model) for an infinite slab. Heat transfer from the cooling pipe network was treated as 2-D heat flow. Only a limited number of nodes were required to obtain reliable results. The use of 6th order RC-thermal model produced a set of ordinary differential equations that were solved using MATLAB - R2012a. The computer program was written to cover all possible initial conditions, material properties, TAR system geometry and hourly solar radiation. The cool water supply was considered time dependent with the variation of the ambient wet bulb temperature. Results from RC-thermal modeling were compared with experimental measurements for a second story room measuring 5.5 m x 4 m x 3 m at Amarah city/ Iraq (31.865 ˚N, 47.128 ˚E) for 21 July, 2013. The roof was constructed of 200 mm concrete slab, 150 mm turf and 50 mm insulation. Galvanized 13 mm steel pipe coils were buried in the roof slab with a pipe occupation ratio of 0.12. The walls were constructed of 240 mm common brick with 10mm cement plaster on the inside and outside surfaces and 20 mm Styrofoam insulation on the inside surface and covered with PVC panel. Thermistors were used to measure the indoor and outdoor temperatures, TAR system water inlet and outlet temperatures and temperature distribution inside the concrete slab. The effect of pipe spacing and water mass flow rate were evaluated. Agreement was good between the experimental and RC-thermal model. Concrete core temperature reaches the supply water temperature faster for lower pipe spacing. Heat extracted from the space increased with water mass flow rate to an optimum of 0.0088 kg/s.m².

This paper presents thermal characteristics analysis of a modified Closed Wet Cooling Tower (CWCT) based on heat and mass transfer principles to improve the performance of this tower in Iraq. A prototype of CWCT optimized by added packing was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of the air measured at intermediate points of the heat exchanger and packing. Heat exchangers consist of four rows and eight columns for an inline tubes arrangement and six rows and five columns for staggered tubes arrangement. According to experimental data, the inline tubes arrangement has a better thermal performance than the staggered tubes arrangement. The inline tubes arrangement enhanced thermal efficiency more than (7%) compared to the staggered tubes arrangement. Furthermore the effect of added packing to CWCT on thermal performance was significant compared to CWCT without packing. Comparing CWCT with packing, it has been observed that the best performance for the CWCT with packing under heat exchanger. It can be watched that the thermal efficiency for CWCT with packing under heat exchanger and CWCT with packing above heat exchanger approximately (28%) and (16%) higher than that CWCT without packing respectively. This study provides correlations to predict heat and mass transfer considering the influences of operational parameters for both inline and staggered heat exchanger tubes arrangement.

This paper presents the Taguchi approach for optimization of hardness for shape memory alloy
(Cu-Al-Ni) . The influence of powder metallurgy parameters on hardness has been investigated.
Taguchi technique and ANOVA were used for analysis. Nine experimental runs based on
Taguchi’s L9 orthogonal array were performed (OA),for two parameters was study (Pressure and
sintering temperature) for three different levels (300 ,500 and 700) MPa ,(700 ,800 and 900)oC
respectively . Main effect, signal-to-noise (S/N) ratio was study, and analysis of variance
(ANOVA) using to investigate the micro-hardness characteristics of the shape memory alloy
.after application the result of study shown the height hardness at the level 2 of pressure and
level 1 of temperature (A2B1) by taguchi technique at magnitude value 500MPa and 700 ºC. The
best effective factor at ANOVA has pressure 36.39%. the interaction given the best pressure 500
MPa and Temperature 800 ºC.

The paper uses the Direct Synthesis (DS) method for tuning the Proportional
Integral Derivative (PID) controller for controlling the DC servo motor. Two
algorithms are presented for enhancing the performance of the suggested PID
controller. These algorithms are Back-Propagation Neural Network and Particle
Swarm Optimization (PSO). The performance and characteristics of DC servo motor
are explained. The simulation results that obtained by using Matlab program show
that the steady state error is eliminated with shorter adjusted time when using these
algorithms with PID controller. A comparative between the two algorithms are
described in this paper to show their effectiveness, which is found that the PSO
algorithm gives better results to improve the PID controller for controlling the DC
servo motor compared to the neural network algorithm.

This study included the extraction properties of spatial and morphological basins studied using
the Soil and Water Assessment Tool (SWAT) model linked to (GIS) to find the amount of
sediment and rates of flow that flows into the Haditha reservoir . The aim of this study is
determine the amount of sediment coming from the valleys and flowing into the Haditha Dam
reservoir for 25 years ago for the period (1985-2010) and its impact on design lifetime of the
Haditha Dam reservoir and to determine the best ways to reduce the sediment transport. The
result indicated that total amount of sediment coming from all valleys about (2.56 * 106 ton). The
maximum annual total sediment load was about (488.22 * 103 ton) in year 1988 due to the
surface runoff about 167.79 * 106 m3, while the minimum annual total sediment load was about
(8.62 * 103 ton) in year 2007. This due to the total runoff volume that was 5.67×106 m3. Model
calibration and verification were carry out using flow rate and sediment yield data observed at
the study area and the results were satisfactory.

Cams are considered as one of the most important mechanical components that depends the
contact action to do its job and suffer a lot of with drawbacks to be predicted and overcame in
the design process. this work aims to investigate the induced cam contact and the maximum
shear stress energy or (von misses) stresses during the course of action analytically using Hertz
contact stress equation and the principal stress formulations to find the maximum stress value
and its position beneath the contacting surfaces. The experimental investigation adopted two
dimensions photoelastic technique to analyze cam stresses under a plane polarized light. The
problem has been numerically simulated using Ansys software version 15 as FE solver and
depending on Lagrange and Penalty contact algorithm. The effect of cam geometry,
characterized by some parameters such as follower radius, face width, rise and return angles, and
modulus of elasticity on the contact stress is investigated aiming to minimize the induced
stresses.

The recent development in communication technologies between individuals allows for the
establishment of more informal collaborative map data projects which are called volunteered
geographic information (VGI). These projects, such as OpenStreetMap (OSM) project, seek to
create free alternative maps which let users add or input new materials to the data of others. The
information of different VGI data sources is often not compliant to any standard and each
organization is producing a dataset at various level of richness. In this research the assessment of
semantic data quality provided by web sources, e.g. OSM will depend on a comparison with the
information from standard sources. This will include the validity of semantic accuracy as one of
the most important parameter of spatial data quality parameters. Semantic similarity testing
covered feature classification, in effect comparing possible categories (legend classes) and actual
attributes attached to features. This will be achieved by developing a tool, using Matlab
programming language, for analysing and examining OSM semantic accuracy. To identify the
strength of semantic accuracy assessment strategy, there are many factors should be considered.
For instance, the confusion matrix of feature classifications can be assessed, and different
statistical tests should be passed. The results revealed good semantic accuracy of OSM datasets.