Engineering and Technology Journal

Urban growth driven by uncontrolled expansion is one of the greatest problems that reduces the fertile lands in Karbala Governorate, Iraq. This phenomenon is the cause for variety of urban environmental problems such as an increase in local temperature, cost of land, and loss of agricultural produce. Multiple images of different time periods were used, passing them through a series of image processing steps according to the methodology of work to achieve the aims of the paper by calculating land cover changes for Karbala City from 1992 to 2013. The aim of this research is to take the temporal and subtle changes in urbanization and land cover primarily to take into account a superior perception of the connection and activities between urban growth and urban environmental problems. To take action and greater control of land surface features, the data from Landsat 4 (MSS) 1992, Landsat 7 Thematic Mapper (ETM) 2003, and Landsat 8 Operational Land Imager (OLI) 2013 were used to deliver the research's aim.

Elevated CO2 rates in a building affect the health of the occupant. This paper deals with an experimental and numerical analysis conducted in a full-scale test room located in the Department of Mechanical Engineering at the University of Technology. The experiments and CFD were conducted for analyzing ventilation performance. It is a study on the effect of the discharge airflow rate of the ceiling type air-conditioner on ventilation performance in the lecture room with the mixing ventilation. Most obtained findings show that database and questionnaires analyzed prefer heights between 0.2 m to 1.2 m in the middle of an occupied zone and breathing zone height of between 0.75 m to 1.8 given in the literature surveyed. It is noticed the mismatch of internal conditions with thermal comfort, and indoor air quality recommended by [ASHRAE Standard 62, ANSI / ASHRAE Standard 55-2010]. CFD simulations have been carried to provide insights on the indoor air quality and comfort conditions throughout the classroom. Particle concentrations, thermal conditions, and modified ventilation system solutions are reported

Reconstruction of the mandible after severe trauma is one of the most difficult challenges facing oral and maxillofacial surgery. The mandible is an essential element in the appearance of the human face that gives the distinctive shape of the face, holds. This paper aims to propose a methodology that allows the surgeon to perform virtual surgery by investing engineering programs to place the implant by default and with high accuracy within the mandible based on the patient's medical data. The current study involved a 35-year-old man suffering from a traffic accident in the mandible with multiple fractures of the facial bones. Basically, an identification of the steps required to perform virtual surgery and modeling images from the CBCT technology has been done by using the software proposed in the research. The implant model is designed as a mesh model, allowing the patient to return to a normal position. Moreover, an application of FEA procedures using the Solidworks simulation software to test and verify the mechanical properties of the final transplant.

Production Line Balancing (PLB) is the technique of assigning the operations to workstations in such a way that the assignment minimizes the idle time between workstations. PLB aims to equator the workload in each workstation to assure maximum production flow. By adding machine in specific configurations is one treatment which leads to this leveling in workload. This research studies the different efficiencies of the added machine and the effect of these efficiencies on line balancing to select the machine with suitable efficiency. This will be led to reduce the idle time between workstations and increasing production flow. The work time considered as the efficiency criterion for this case study. The study has been implemented on a dumb truck production line and resulted in increasing the line efficiency to 81.7%.

This research work presents a nonlinear finite element investigation on the behavior of high strength fiber reinforced concrete beams. This investigation is carried out in order to get a better understanding of their behavior throughout the entire loading history. The three- dimensional 20-node brick elements are used to model the concrete, while the reinforcing bars are modeled as axial members embedded within the concrete brick elements. The compressive behavior of concrete is simulated by an elastic-plastic work-hardening model followed by a perfectly plastic response, which terminate at the onset of crushing. In tension, a fixed smeared crack model has been used.

Polyvinyl-chloride (PVC) was dehydrochlorinated by alkaline-solution (NaOH) in determining molarity (3.0 M) followed by grafting with acrylamide (AM) monomer onto dehydrochlorinated PVC (DHPVC) backbone by free-radical graft copolymerization to produce new grafted polymer referred as graft 3M. Then investigated the effect of polyvinyl pyrrolidone (PVP) addition on the grafted polymer. Membranes from pure PVC, graft 3M, and graft 3M/ PVP were synthesis via a phase inversion method. The successful AM grafting onto PVC was confirmed by characterization of the membranes by Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscope (FESEM) analysis, porosity, pore size, and contact angle measurements. The new synthesis (graft 3M) and (graft 3M/ PVP) membranes show excellent hydrophilicity in compared to pure PVC membranes, confirmed by higher pure water flux (PWF). The graft 3M/ 3wt.% PVP membrane exhibited the highest pure water permeate flux was about 540 L/m2 h at 28 °C of feed temperature and 1bar of pressure, i.e. was improved by about 270 times compared to the unmodified PVC membrane and 2.35 times compared to the graft 3M membrane

This study aims to examine the formability of drawing cups having square shapes through direct deep drawing process on a single action press through one pass. This can be accomplished by conducting an FE simulation and performing an experimental investigation on steel substrate type AISI 1008 blank with diameter and thickness dimensions 80, 0.5 mm respectively. To explore and analyze the formability of such a drawing process, two process parameters have been included in this work which is the speed of punch (30 and 300 mm/min) and the lubrication state (with machine oil and dry drawing). Both direct and indirect measurements of thickness strain have been adopted as an indicator of the sheet formability. The results of both FE simulation and experimental work demonstrate that the square drawing of the AISI sheet has been accomplished for all the four cups produced since the highest thinning over the cup wall does not exceed 25% of the original thickness. Generally, there is a good match between the experimental values of the indirect method and the FEM results for all models such that the largest deviation is about 25%. The direct method of thickness measurement is determined to be non-confident as strain values are practically unacceptable. Additionally, higher formability of the sheet has been realized at lower punch speeds. Furthermore, no significant difference has been observed in the formability at both speeds of punch when using a lubricant compared to the dry drawing operation

Y-Source Impedance Network (YSN) is one of the most suitable for providing high voltage gain. It generatesa high voltage gain by using a small shoot-through duty cycle, which makes it suitable in applications require a wide range of input voltages such as the Photovoltaic (PV) power plants. However, traditional (YSNs) are unable to boost low voltages in certain applications to the DC-link voltage (about 400V) since it requires a high number of the turns ratio. Higher turns ratio implies higher leakage inductance resulting in higher DC-link voltage spikes. Also, traditional YSNs have high voltage stresses across the components. In this paper, a developed new transformerless Micro-Inverter (MI) is presented that can overcome all the aforementioned drawbacks. The proposed MI has been developed and designed to eliminate both the leakage inductance due to three-winding coupled transformer and leakage current due to using transformerless MI configuration. In addition, the proposed MI reduced the components' stress significantly and increases the converter voltage gain capability in one single-stage. The proposed high boost ratio transformerless MI is analyzed through the PLECS software simulator and implemented in a small scale MI prototype to ensure the results agree with the analysis and simulation results.

In this paper, a new design of the model reference control scheme is proposed in a class of nonlinear strict-feedback system. First, the system is analyzed using Lyapunov stability analysis. Next, a model reference is used to improve system performance. Then, the Integral Square Error (ISE) is considered as a cost function to drive the error between the reference model and the system to zero. After that, a powerful metaheuristic optimization method is used to optimize the parameters of the proposed controller. Finally, the results show that the proposed controller can effectively compensate for the strictly-feedback nonlinear system with more desirable performance

Discharge Machining is a non-traditional machining technique and usually applied for hard metals and complex shapes that difficult to machining in the traditional cutting process. This process depends on different parameters that can affect the material removal rate and surface roughness. The electrode material is one of the important parameters in Electro –Discharge Machining (EDM). In this paper, the experimental work carried out by using a composite material electrode and the workpiece material from a high-speed steel plate. The cutting conditions: current (10 Amps, 12 Amps, 14 Amps), pulse on time (100 μs, 150 μs, 200 μs), pulse off time 25 μs, casting technique has been carried out to prepare the composite electrodes copper-sliver. The experimental results showed that Copper-Sliver (weight ratio70:30) gives better results than commonly electrode copper, Material Removal Rate (MRR) Copper-Sliver composite electrode reach to 0.225 gm/min higher than the pure Copper electrode. The lower value of the tool wear rate achieved with the composite electrode is 0.0001 gm/min. The surface roughness of the workpiece improved with a composite electrode compared with the pure electrode

Absorption of CO2 into promoted-NH3 solution utilize a packed column (1.25 m long, 0.05m inside diameter) was examined in the present work. The process performance of four different blended promoters monoethanolamine (MEA)+ piperazine (PZ), piperazine (PZ)+ potassium argininate (ArgK) and monoethanolamine +potassium argininate was compared with unpromoted-NH3 solution by evaluated the absorption rate (φ_(CO_2 )) and overall mass transfer coefficient (K_(G,CO_2.) a_v) over the operating ranges of the studied process variables (1-15Kpa initial partial pressure of CO2, 5-15 Liter/min gas flow rate, 0.25-0.85 Liter/min liquid flow rate). The results exhibit that the absorption behavior and efficiency can be enhanced by rising volumetric liquid flow rate and initial CO2 partial pressure. However, the gas flow rate should be kept at a suitable value on the controlling gas film. Furthermore, it has been observed that the (PZ+ArgK) promoter was the major species that can accelerate the absorption rate and reached almost 66.166% up to123.23% over that of the unpromoted-NH3 solution.

In this work, effluent wastewater treated by using cyclopentane-water Clathrate system to treat water contaminates with phenols at concentrations (300, 250, 200, 150, 100 and 50) ppm in order to investigate the capability of process performance. Clathrate or hydrate are strong crystal structures including water (host particles) and little particles (guest particles). The experiments were conducted at different cyclopentane-water volume ratios (1: 2 and 1: 4). The work was done in a 250 ml glass cell with an electric mixer at a constant speed of 280 cycles per minute. Phenol was highest removal percent at 300ppm at 1: 4volume ratio was (92.3%), while the lowest concentration at 50 ppm and 1: 2volume ratio was (55%). Yield and Enrich factor had the highest values at the lowest concentration 50ppm and 1:2 volume ratio were (85% and 2.42) respectively. The technique of the Clathrate proved that it has a high capacity in the separation and achieve high removal percentage compared to other methods at standard conditions when the pressure of 1 atmosphere and temperature higher than the degree of freezing water and less economic costs compared to other methods..

A modified version of the artificial Bee Colony Algorithm (ABC) was suggested namely Adaptive Dimension Limit- Artificial Bee Colony Algorithm (ADL-ABC). To determine the optimum global path for mobile robot that satisfies the chosen criteria for shortest distance and collision–free with circular shaped static obstacles on robot environment. The cubic polynomial connects the start point to the end point through three via points used, so the generated paths are smooth and achievable by the robot. Two case studies (or scenarios) are presented in this task and comparative research (or study) is adopted between two algorithm’s results in order to evaluate the performance of the suggested algorithm. The results of the simulation showed that modified parameter (dynamic control limit) is avoiding static number of limit which excludes unnecessary Iteration, so it can find solution with minimum number of iterations and less computational time. From tables of result if there is an equal distance along the path such as in case A (14.490, 14.459) unit, there will be a reduction in time approximately to halve at percentage 5%.

The development in the manufacturing of micro-truss structures has demonstrated the effectiveness of brazing for assembling these sandwiches, which opens new opportunities for cost-effective and high-quality truss manufacturing. An evolving idea in micro-truss manufacturing is the possibility of forming these structures in different shapes with the aid of elevated temperature. This work investigates the formability and elongation of aluminum alloy sheets typically used for micro-truss manufacturing, namely AA5083 and AA3003. Tensile tests were performed at a temperature in the range of 25-500 ○C and strain rate in the range of 2x10-4 -10-2 s-1. The results showed that the clad layer in AA3003 exhibited an insignificant effect on the formability and elongation of AA3003. The formability of the two alloys was improved significantly with values of m as high as 0.4 and 0.13 for AA5083 and AA3003 at 500 °C. While the elongation of both AA5083 and AA3003 was improved at a higher temperature, the elongation of AA5083 was inversely related to strain rate. It was concluded that the higher the temperature is the better the formability and elongation of the two alloys but at the expense of work hardening. This suggests a trade-off situation between formability and strength.

Electrical discharge machining (EDM) is one of the most common non-traditional processes for the manufacture of high precision parts and complex shapes. The EDM process depends on the heat energy between the work material and the tool electrode. This study focused on the material removal rate (MRR), the surface roughness, and tool wear in a 304 stainless steel EDM. The composite electrode consisted of copper (Cu) and silicon carbide (SiC). The current effects imposed on the working material, as well as the pulses that change over time during the experiment. When the current used is (8, 5, 3, 2, 1.5) A, the pulse time used is (12, 25) μs and the size of the space used is (1) mm. Optimum surface roughness under a current of 1.5 A and the pulse time of 25 μs with a maximum MRR of 8 A and the pulse duration of 25 μs.