Journal of Engineering and Sustainable Development (JEASD)

The presence of salts in soil may cause severe problems to structures constructed on it, because of the high dissolution of salt particles when subjected to water from any source. The primary objective of this study is to investigate the behavior of single footing over different percentages of sabkha soil (5%, 10%, 20%, and 40%). A laboratory model, manufactured locally was used for this study. The sabkha soil is prepared by mixing ordinary soil with specified quantities of sodium chloride salt to have different percentages of salinity. The footing used is a 75mm diameter circular steel plate and 20mm thickness and holds fixed stress, with the aid of a loading frame which in turn is attached to a firm table. Dial gauges are attached to the fixed table and placed on the footing, to record settlement with time. The study includes also the effect of cement and lime addition with different percentages(1%, 3%, and 5%), on the collapsibility of sabkha soil. Mixing sabkha soil with 5% of cement will reduce collapse potential (S/B%)* upon wetting, by 97%. While mixing sabkha soil with 3% lime will reduce collapse settlement by 47%, On the other hand, mixing sabkha soil with 1% cement slurry increases the collapsibility by 3%. This study also shines the light on the effect of compaction on the properties of sabkha soil. The collapse potential (S/B%)* was reduced by 50% when increasing the compaction of sabkha soil model from 17.7 to 19 kN/m3.

In this paper, an experimental investigation has been done for laminar steady-state free-convection heat transfer from a heated hollow cylinder to ambient air inside an open-ended square-section shield with orientation and cylinder diameter effects. Four aluminum heated cylinders of different diameters are employed. The cylinders are heated with various supplied power levels. Six inclinations of a heated cylinder with the vertical position, namely 0o, 15o, 30o, 45o, 60o, and 75o are used. The effects of orientation on local surface temperatures profile along with the heated cylinder, convection heat transfer coefficient, Nusselt number, and Rayleigh number at different diameters and heat inputs to the heating element have been plotted and explained. The experimental results show that the local heat transfer coefficient is maximum at an inclination angle of 75o and at the cylinder base. The present experimental results are compared with previous works shows good agreement.

The structural rehabilitation of reinforced lightweight aggregate concrete beams in shear was studied with resin injection. A series of model beams, reinforced in shear, were loaded in the laboratory until failure, repaired, and again loaded to failure.The variables in the test program were shear span-to-depth ratio 4.0,3.0,2.5,2.0,1.5 and 1.0 ; and shear reinforcement index ,ρvfy= 0.493,0.704 and 0.896 MPa .Experimental failure loads are compared with predictions using ACI 318M-02 code and the modified compression field theory by the program “Response 2000”.After testing, the beams failed due to new diagonal cracks. The ratio of ultimate load to crack load varies from 1.5 for a/d >2 to 2.27 for a/d ≤ 2 (deep beams) . Test results indicate the ACI 318M-02 is conservative.

Baghdad City suffers from severe traffic congestion due to the rapid urban expansion and travel demand growth. Based on many studies, urban rail transit was proposed by experts and related transit agencies as an optimal solution to solve this problem. Accordingly, Baghdad metro route selection based on multi-criteria was proposed to be studied, evaluated, and searched in the present research. The methodology utilizes a GIS to prepare and analyze data. Data were analyzed using a two-stage multiple-criteria decision-making (MCDM) model which includes Analytical Hierarchal Process (AHP) and TOPSIS methods. Moreover, a Geographic Information System (GIS) was used to explore the various route alternatives. To select the best alternative, all alternatives were evaluated against the selected criteria. The weighting system is not only based on experts’ opinions but also includes a set of measures based on real data. Based on the outcomes of the present study, alternative route number 1 can be recognized to be the optimal route in the year 2014, and alternative route 2 is recommended to be adopted to meet the high travel demand requirement in the year 2035.

The stiffening of a rectangular frame is taking place by using bars. Those bars are distributed longitudinally, transversely, inclined, and in mixed shapes. The theoretical deflection of frame free edge is calculated and compared with the (FEM) using MATLAB and ANSYS software programs. A good agreement is found in the (FEM) model as compared with the theoretical and ANSYS results. Different bar distributions gave a different torsional resistance and deflection. Higher torsional resistance is found in the transverse and cross shape of bar distributions. Minitab program is used to analyze the results and minimize the deflection and cost by (DOE). In which, the effect of input factors and their interactions has been studied. The main effect on the deflection and cost has been observed in the inclined bars. A higher reduction in the deflection and cost has been observed in the existence of longitudinal and transverse bars, respectively.

In this paper, a new method of programmed computerizing has been suggested which depends on converting the roads network to the matrix and the representation of this matrix in the adjacency matrix, that a number of rows are an equal number of columns, where the degree of this matrix is equal for a number of the edges plus one in (i) multiplied by a number of the edges plus one in (j) of the roads network (graph). The elements of This matrix will be either (1) which means an existing edge of orientation in one direction connecting between two nodes continuous connection, or (0) and which means there is no edge of orientation connecting between two nodes. And this conversation has been implemented by using a new algorithm characterized by finding the shortest path between two nodes in the roads network, whatever its size, type, and complication degree, in specific lengths, costs and terms and for more accuracy, to implement this algorithm, the matrix has been processed by three basic steps: The first step is to know and determine the number of the paths in the network and it is the first data which must be input to the computer is running the program. The second step is to specify the edges within the installation, each path and its numbers. And the third step is to compare the lengths of the calculated paths to find the shortest path. The results of this proposed algorithm have shown that it has...

Attendance is an important aspect of every educational institute or workplace. Most universities are still using the paper-based attendance system. This paper presents an effective approach to improving the processes of attendance systems using Radio Frequency Identification (RFID) technology. The design of software tools was implemented by using Visual Basic 6.0 for interfacing and a database for persons’ information including RFID tags identification (IDs). The proposed design has Liquid Crystal Display (LCD) to get messages from the application when the identification is done and pass information back to the microcontroller to send this information to the LCD to be displayed.

In this paper, a proposed control strategy is presented to improve the performance of the pulse width modulation PWM boost rectifier when operating under different supply voltage conditions (balanced, unbalanced, and distorted three-phase supply voltages). The proposed control strategy is divided into two parts, the first part is a voltage controller and the second part is the current controller. In the voltage controller, Proportional-Integral (PI) controller is used to regulate the output dc voltage at any desired level and Low Pass Filter LPF to reduce the even-order harmonics which appear in the regulated output dc voltage due to unbalanced input supply voltages. LPF also reduces the even-order harmonics which appear in the reflected dc current (IMAX), this leads to reducing the odd-order harmonics which appear in the input currents. While in the current controller, Enhanced Phase Locked Loop (EPLL) technique is used to obtain sinusoidally and balanced three phases, to construct the reference currents, which are in phase with the fundamental supply voltages Therefore, the supply-side power factor is kept close to unity. A proportional controller is used to give excellent tracking between the line and the reference currents. The complete system with the proposed control strategy is simulated using Matlab/Simulink Version 2012. The results for the complete system using the proposed voltage controller are obtained and compared to the results of the system with the conventional voltage controller proportional-integral PI is used without LPF. THDs for three-phase input line currents are better...

The layout of temporary facilities in a construction site deals with the selection of the most efficient layout in order to operate efficiently and cost-effectively. The layout design seeks the best arrangement of facilities within the available area. In the design process of the layout, many objectives must be considered to effectively utilize people resources, equipment, space, and energy. The research aims to design practical scheme to locate the temporary facilities in construction sites with less travel distance between them, so it has been to follow the scientific methodology of the research included two phases, the first was the study of theoretical research and previous studies relating to research, and represented the second phase of the study process which has been used in two ways, namely: a survey field for a number of experienced in construction sites management and analysis of answers and compare them with the theoretical study while the second way to use the results of phases theory and practice in the design of a mathematical model to accomplish the aim of the research to reach optimum planning for the sites of temporary facilities in construction sites and using the software Matlab to find in the minimum transition between each pair of these facilities and minimum distance between all of the facilities The results showed through a survey of experts need to design places of temporary facilities right before starting the implementation of the project...

The quantum efficiency of a silicon p-υ-n photodetector is present. The analysis to obtain the quantum efficiency takes a uniform doping concentration in each layer into consideration. The theoretical treatment aims to investigate the effect of device parameters on efficiency. Three different cases of incident light wavelengths have been considered; short wavelengths, medium wavelengths, and long wavelengths. There is no wavelength range between them, but when most of the incident light (about 63% or more) is absorbed near the surface, it is called short wavelength, and when most of the light is absorbed in the υ-layer, it is called medium wavelength else called long-wavelength. A high quantum efficiency at the wavelength of interest, combined with its low operating voltage and capability, makes this detector promising for use in communication systems and computer interconnections. Highspeed silicon p-υ-n photodetector operates at 700 nm wavelength is reported. By using a reverse bias voltage control υ-layer width, the high quantum efficiency of 80% is attained corresponding to υ-layer width of 5.36 mand biasing voltage of 2.182 V.The results showed that the quantum efficiency is directly proportional to the width of the υ-layer and biasing voltage. The results are achieved with the aid of MATLAB programming tool version8.1.0.604 (R2013a).

It is well known that the Turbo code's performance is considerably affected by its Interleaver design, which often has random permutation properties. In this paper, we propose deterministic three types of 1-DChaotic Interleavers based on chaotic dynamics that have a random-like behavior to give the Interleaver the required degree of dispersion and correlation factors. Furthermore, 2-D and 3-D Chaotic Interleavers are designed to have good separation parameters that have a major impact on the turbo codes' performance, especially over fading channels. Then, the designed chaotic Interleavers are compared with random ones in terms of performance for random data and measuring the quality of the received image in terms of their PSNRs. The results show that the Multi-dimensional Chaotic Interleavers outperform the random one, in terms of both: BERand the quality of the received image.

The experimental and numerical investigation has been performed in this work to study the enhancement of heat transfer coefficient in a spiral fluted tube heat exchanger with Nanofluid. The shell side was made from a galvanized tube of (65 mm) outer diameter. The tube was made from copper material of (1000 mm) length having (16 mm) equivalent inner diameter and (17 mm) outer diameter, it was inserted inside the shell. Steam was used, as a heating source where constant wall temperature condition (110˚oC) was achieved, and TiO2 /water nanofluid with various volume concentrations (0.08%, 0.1%, 0.2%, and 0.3%) by volume at Reynolds numbers (7000 to 15000) has been employed, as working fluid flows through the inner tube. Fiberglass has been utilized to cover the outer surface of the shell for reducing heat losses. The performance of a spiral fluted tube heat exchanger with and without nanofluid was investigated experimentally. Experimental results reveal that the use of a spiral fluted tube without nanofluid leads to an increase (28-33) % in heat transfer coefficient compared with a smooth tube, and the maximum increase in heat transfer coefficient occurs when using a spiral fluted tube with nanofluid at 0.3% volume concentration was about (25-28) % higher than the pure water in spiral fluted tube. Empirical correlations for water and nanofluid were represented by the Nusselt number. Numerical simulation has been carried out on the present heat exchanger to analyze both flow field and heat transfer using ANSYS 14, FLUENT package...

This paper presents a design and implementation of a Wireless modem with 16-QAM modulation, convolution, and differential coding based on SDR using the MATLAB system generator model, for WiMAX applications. The key difficulties used in the modulation schemes for WiMAX design, as mentioned by IEEE 802.16 standard, need ample hardware if all the modulation schemes and code rates have to be designed on FPGA. The implemented modem performance has been checked using the error rate calculation as an indicator, with different channel noise environments. The results of the resource estimator showed the use of an appropriate number of slices, and another resource of FPGA for the completion of this design and this is encouraging for the use of this design in a variety of other applications of wireless communications.

The use of waste materials in buildings is an innovative approach toward sustainability. The objective of this paper is to study the properties and behavior of cement mortar using eggshells wastes. Various low concentrations of eggshell powder (ESP) (0,1,3,5, 7, and 10 wt%) were used as partial replacement of cement in the mortar of (1:2) mixing ratio by weight. The maximum particle size of ESP is 75 μm. The soundness of cement in ESP-cement pastes was evaluated using the Le Chatelier method. The influence of ESP on the strengths of cement mortar was investigated by means of compression and flexural tests at various curing periods. It was found that there was no negative impact of ESP on the soundness of cement. A significant enhancement in compressive strength was recorded for all ESP-cement mortars at 7 days and 28 days. The highest improvements, (31.63%) and (11.65%), were observed for samples with 10wt% and 5 wt% of ESP respectively. At moderate periods of curing, samples with 1 wt% of ESP have the highest enhancements in compressive strength of about (8.93%) and (1.75%) for 42 days and 56 days respectively. A reduction in compressive strength was observed for all samples at late ages (70 days and 90 days). In terms of flexural strength, the addition of ESP (up to 5 wt%) results in an improvement in the flexural strength when compared with the control samples. The highest enhancement (21.20%) was recorded when cement was replaced with only 1 wt% at 7 days.

A three-layer artificial neural network model was developed to predict the removal efficiency of Cu(II) ions from simulated wastewater by fungal biomass based on 85 batch experiments. The effect of different parameters such as contact time between adsorbate and adsorbent (10-180 min), initial pH of the solution (3-7), initial metal concentration (50-250 mg/L), adsorbent dosage (0.05-2 g/100 mL), agitation speed (0-250 rpm) and temperature (10-60 ºC) were studied. The best values of these parameters that achieved the maximum removal efficiency (=95 %) of Cu(II) were 90 min, 6, 50 mg/L, 2 g/100 mL, 200 rpm, and 20 ºC, respectively. The present model was able to predict adsorption efficiency with a tangent sigmoid transfer function (tansig) at the hidden layer with 8 neurons and a linear transfer function (purelin) at the output layer. The linear regression between the network outputs and the corresponding targets was proven to be satisfactory with a correlation coefficient of greater than 0.99778 for the used six model variables. The sensitivity analysis based on the artificial neural network indicated that the initial pH of the solution with a relative importance of 22.1% appeared to be the most influential parameter in the Cu(II) removal, followed by dosage (19.5%), agitation speed (18.2%), temperature (14.1%), time (13.3%), and concentration (12.8%).

A strengthening method that was used quite extensively during the mid-1970s is steel plate bonding, this method has gained a renaissance in the last decades. This paper presents experimental work including an investigation of four simply supported reinforced concrete beams under pure torsion. The first beam was the control beam without strengthening. The other three beams were strengthened externally by bolted steel plates. The most important variable was the spacing between shear connectors. The discussion of results is based on torque-twist behavior, beam longitudinal elongation behavior, and the influence of the spacing between shear connectors on cracking torque, ultimate torque, and failure modes.

The research aims to study the effect of rice husks ash or sawdust ash addition to the soil of locally produced clayey bricks on its properties like compressive Strength, flexural Strength, Water absorption, efflorescence and density. A(60) bricks were brought from Mahaweel governmental bricks factory in Babylon governorate for executing the above mentioned reference tests. Crushed soil was brought from bricks manufacturing stages of the mentioned factory for individual addition of the two ash types to the soil at ratio of (2,3.5,5 and 6.5)% from soil weight. The mixed raw bricks with ashes were manufactured in similar factory work circumstances and burnt in same factory kiln at a temperature of (900)C˚. A(480) mixed bricks were manufactured to execute the tests of the mixed bricks with the two ash types at different addition ratios. The results showed that the best rice husks ash addition ratio was (3.5)% of bricks soil weight for the compressive Strength was increased by(16.53)%, flexural Strength was increased by(10.80)% as average for the test cases at filling the brick holes with mortar and without filling, Water absorption was also increased by(12.31)% , the efflorescence was increased by(3.86)% and the density was decreased by (6.39)% compared with the reference.

Most consulting firms in third world countries' tracking systems and methods are not commensurate with the ambition and the goals set before them, and it is necessary to operate these offices to provide input from administrative staff, skills and systems, and methods of modern technology. This research aims to evaluate the current system adopted for the management of design in Diyala province, using the technique IPV to determine the kinks in it, is by identifying the criteria used to select the office optimization, and also to identify a list of offices operating in Diyala province in order to choose the best of them in terms of quality of design of construction projects. For the purpose of accomplishing this objective, it has been collecting its own data from the literature that deals with a substantive domestic product of vectors (IPV) and management of structural design, and finally personal interviews of qualified designers and implementers in construction companies. Showed the results of data analysis for the sample that the standard use of computer technology and design review and development is the most important criteria for bilateral comparisons between bureaus, the Engineering Consulting bureau at the University of Diyala has received the largest share of the relative importance compared with other offices, and eventually reached to a set of conclusions and recommendations including the need for efficient management styles necessary to assess the consulting offices in various fields, especially in the field of quality designs in construction projects, including technical IPV.