Journal of Engineering

This paper investigates the issue of surface-type effects on traffic noise in Baghdad. Since the raw materials for both flexible and rigid paving are available from local sources, the decision on selecting the type of paving depends on the budget of the project and the road's importance and function. Knowing that for high traffic volumes and a high percentage of heavy vehicles, rigid pavement is more suitable compared to flexible pavement. In Baghdad, some highways consist of flexible pavement and others of combined pavement (flexible segments and rigid segments), so the study of the effect of surface type on traffic noise becomes an important matter. This study selected three highways: one with flexible pavement and two with combined pavement. The results showed that the traffic noise generated by traffic on rigid pavement generates more noise than traffic on flexible pavement by about 2 dBA. A prediction model was generated to predict traffic noise depending on five variables (vehicle speed, traffic volume, skid number, distance between the edge of the inner lane and the sound level meter, and surface type). The measured traffic noise levels ranged from 73.23 to 82.86 dBA, which exceeded the permitted limits compared to the permissible Iraqi standards.

The study aims to determine drinking water quality in Al-Najaf City by collecting samples throughout Al-Najaf city and comparing the results with the Iraqi guidelines (IQS 417) and World Health Organization (WHO) guidelines, as well as to calculate the WQI. Samples were tested in the laboratory between December 2021 and June 2022. The results showed that multiple parameters exceeded the allowable limits during both testing periods; during winter months, the results of TDS and turbidity exceeded the upper limits in multiple locations. Total hardness values also exceeded the limit of 500 ppm for all samples taken in the winter period. For magnesium and calcium, summer measurements were mainly within limits, unlike winter period measurements which mostly exceeded the limits. Residual chlorine tests in winter had higher concentrations, generally ranging from 0.25 to 0.8 mg/l. While During summer, concentrations dropped below the allowable limit in multiple sampling points. The study concluded that the majority of the water samples gathered during the winter months were of poor quality as the total WQI values were between (99-110), While the total WQI values for water samples collected during the summer period were rated as good quality water ranged between (75-81).

Rainwater harvesting could be a possible solution to decrease the consequences of water scarcity and energy deficiency in Iraq and the Kurdistan Region of Iraq (KRI). This study aims to calculate the water and energy (electricity) saved by rainwater harvesting for rooftops and green areas in Sulaimani city, KR, Iraq. Various data were acquired from different formal entities in Sulaimani city. Moreover, Google Earth and ArcMap 10.4 software were used for digitizing and calculating the total rooftop and green areas. The results showed that for the used runoff coefficients (0.8 and 0.95), the harvested rainwater volumes were 2901563 and 12197131 m³ during the study period (2005 – 2006) and (2019-2020). Moreover, by comparing the study area's rainwater harvesting volume and water production, the water-saving percentage was 8.21 to 22.68%. Furthermore, the energy-saving percentage recorded was from 7.70 to 22.5% by implementing rooftop rainwater harvesting. On the other hand, using average daily rainfall data for the year (2005-2020), the total water-saving percentage and the total energy-saving rate for both runoff coefficients were very close. Water and energy-saving results were calculated using year-by-year rainfall data, taking more time and effort for its computation. Moreover, the water-saving percentage for the selected green area was not encouraging, and the results were between 0.73 and 11.15%. Additionally, the storage size for three typical buildings was calculated, and the results show the average storage size required for rainwater harvesting using daily rainfall data was 11.2 to 14.68 m³ (house), 291.42 to 422.33 m³ (school), and 10.5 to 11.41 m³ (hotel) for runoff coefficients of 0.8 and 0.95, respectively.

The increasing drinking water demand in many countries leads to an increase in the use of desalination plants, which are considered a great solution for water treatment processes. Reverse osmosis (RO) and electro-dialysis (ED) systems are the most popular membrane processes used to desalinate water at high salinity. Both systems work by separating the ionic contaminates and disposing of them as a brine solution, but ED uses electrical current as a driving force while RO uses osmotic pressure. A direct comparison of reverse osmosis and electro-dialysis systems is needed to highlight process development similarities and variances. This work aims to provide an overview of previous studies on reverse osmosis and electro-dialysis systems related to membrane module and design processes; energy consumption; cost analysis; operational problems; efficiency of saline removal; and environmental impacts of brine disposal. RO system uses osmotic pressure as a driving force to force water through the membrane with less energy than other desalination systems. The enhancements in membrane materials and power recovery of the unit have massively decreased the price of RO units. ED system uses an electrical current to push dissolved ions across ion exchange membranes. The results of this review showed that desalination plants must be integrated with renewable energy to reduce power consumption and costs related to energy. Various technologies, including treatment processes and disposal methods, must be used to control concentrated solutions resulting from desalination processes because 5 to 33% of the total cost of the desalination process is associated with brine disposal.

Moisture damage is one of the most significant troubles that destroy asphaltic pavement and reduces road serviceability. Recently, academics have noticed a trend to utilize fibers to enhance the efficiency of asphalt pavement. This research explores the effect of low-cost ceramic fiber, which has high tensile strength and a very high thermal insulation coefficient, on the asphalt mixture's characteristics by adding three different proportions (0.75%, 1.5%, and 2.25%). The Marshall test and the Tensile Strength Ratio Test (TSR) were utilized to describe the impact of ceramic fiber on the characteristics of Marshall and the moisture susceptibility of the hot mix asphalt mixture. The Field Emission Scanning Electron Microscopy (FE-SEM) analysis was used to investigate ceramic fibers' microscopic structure and clarify the mechanics of their improved behavior and their distribution within the asphalt concrete mixture. The results showed that the incorporation of ceramic fibers improved the Marshall properties and the asphalt mixture's susceptibility to moisture damage with an optimum fiber content equal to 1.5%, where Marshall stability increased by 39.04%, and the TSR increased by 11.06% at this content compared with the control asphalt mixture.

In this study, a three-dimensional model was created to simulate groundwater in Al-Haydariyah area of the governorate of Al-Najaf. A solid model was created to utilize the cross sections of 25 boreholes in the research region, and it was made out of two layers: sand and clay. The steady-state calibration was employed in six observation wells to calibrate the model and establish the hydraulic conductivity, which was 17.49 m/d for sand and 1.042 m/d for clay, with a recharge rate of 0.00007 m/day. The wells in the research region were reallocated with a distance of 1500 m between each well, resulting in 140 wells evenly distributed throughout the study area and with a discharge of 5 l/s, and the scenarios were run for 1000 days to explore the impact of over-pumping on groundwater levels. The wells were operated at three different operating hours: 4, 8, and 12 h/d. According to the results, the largest water table decrease for each scenario was 0.35, 8.25, and 8.68 m, respectively. It was discovered that the first scenario, with an operating duration of 4 h/day and a discharge of 72 l/s, was the best scenario in which dry cells did not happen.

Moisture damage is one of the most significant troubles that destroy asphaltic pavement and reduces road serviceability. Recently, academics have noticed a trend to utilize fibers to enhance the efficiency of asphalt pavement. This research explores the effect of low-cost ceramic fiber, which has high tensile strength and a very high thermal insulation coefficient, on the asphalt mixture's characteristics by adding three different proportions (0.75%, 1.5%, and 2.25%). The Marshall test and the Tensile Strength Ratio Test (TSR) were utilized to describe the impact of ceramic fiber on the characteristics of Marshall and the moisture susceptibility of the hot mix asphalt mixture. The Field Emission Scanning Electron Microscopy (FE-SEM) analysis was used to investigate ceramic fibers' microscopic structure and clarify the mechanics of their improved behavior and their distribution within the asphalt concrete mixture. The results showed that the incorporation of ceramic fibers improved the Marshall properties and the asphalt mixture's susceptibility to moisture damage with an optimum fiber content equal to 1.5%, where Marshall stability increased by 39.04%, and the TSR increased by 11.06% at this content compared with the control asphalt mixture.

To maintain river flows necessary to meet social and ecological objectives, instream environmental flows are frequently used as a strategy. The capability of three alternative historical flow approaches to protect against low flows is shown in this study using gage stations in the Shatt Al-Hillah River in Iraq. The extension of the Shatt al-Hillah River is the focus of this research discussion on environmental flow assessment. The available data on discharge in this research were adopted for ten years from 2012-2021. Different flow methods were adopted to establish a minimum environmental flow in the Shatt Al-Hillah River. Three hydrological-based approaches: Tennant, modified Tennant, and low-flow metrics like 7Q10, were used to compare the results of the methods with the provision of a minimal environmental flow. The Tennant method relies on 30 % of the annual discharge rate as the minimum environmental instream flow. The modified Tennant method is based on 30% of the monthly average discharge rate as a minimum environmental instream flow. The 7Q10 method is based on the lowest daily discharge rate in 7 consecutive days for ten years. The results showed that the minimum instream environmental flow given by the Tennant method is 42.26 m³/s while the lowest value of the minimum instream environmental flow obtained from modified Tennant was 37.2 m³/s in January, and the largest value was 47.22 m³/s in August. The one obtained by the 7Q10 method was 50 m³/s in this research.

Moisture damage is described as a reduction in stiffness and strength durability in asphalt mixtures due to moisture. This study investigated the influence of adding nano silica (NS) to the Asphalt on the moisture susceptibility of hot-mix-asphalt (HMA) mixtures under different aging conditions. NS was mixed with asphalt binder at concentrations of 2%, 4%, and 6% by weight of the binder. To detect the microstructure changes of modified Asphalt and estimate the dispersion of NS within the Asphalt, the field emission scanning electron microscope (FE-SEM) was used. To examine the performance of Asphalt mixed with NS at different aging stages (short-term and long-term aging), asphalt mixture tests such as Marshall stability, flow, and Tensile Strength Ratio Test (TSR) were performed. According to the FESEM images, the NS particles in the mixture were sufficiently dispersed. The findings demonstrate that the NS enhances pavement performance by enhancing stability and volumetric characteristics and reducing susceptibility to moisture damage. Furthermore, TSR values of aged specimens show that increasing the NS content significantly reduces susceptibility to moisture and oxidative aging.

The water supply network inside the building is of high importance due to direct contact with the user that must be optimally designed to meet the water needs of users. This work aims to review previous research and scientific theories that deal with the design of water networks inside buildings, from calculating the amount of consumption and the optimal distribution of the network, as well as ways to rationalize the use of water by the consumer. The process of pumping domestic water starts from water treatment plants to be fed to the public distribution networks, then reaching a distribution network inside the building till it is provided to the user. The design of the water supply network inside the building is mainly affected by the amount of water consumed in the building. On this basis, the pipes' dimensions and the water tank's volume are determined. The operating pressure of the water supply network inside the building is calculated to overcome the height difference and the friction inside the pipes and provide sufficient pressure to operate the most remote fixture. The most important results of the research are that the optimal use of the water distribution network inside the buildings is achieved by the correct design and implementation using skilled labor, materials, and devices of high quality and rationalization of water consumption by the user.

Non-orthogonal Multiple Access (NOMA) is a multiple-access technique allowing multiusers to share the same communication resources, increasing spectral efficiency and throughput. NOMA has been shown to provide significant performance gains over orthogonal multiple access (OMA) regarding spectral efficiency and throughput. In this paper, two scenarios of NOMA are analyzed and simulated, involving two users and multiple users (four users) to evaluate NOMA's performance. The simulated results indicate that the achievable sum rate for the two users’ scenarios is 16.7 (bps/Hz), while for the multi-users scenario is 20.69 (bps/Hz) at transmitted power of 25 dBm. The BER for two users’ scenarios is 0.004202 and 0.001564 for user 1 and user 2, respectively, while the BER for multi-users scenario are 0.001738, 0.000706, 0.000286, and 0.000028 for user 1, user 2, user 3, and user 4 respectively. In addition, this paper has compared NOMA with OMA in terms of achievable sum rate. The obtained results indicate that an improvement is achieved for two users NOMA (16.7 (bps/Hz)) compared with OMA (15.53(bps/Hz)), while for multi-users NOMA (20.69 (bps/Hz)) compared with OMA (15.79 (bps/Hz)) at transmitted power of 25 dBm.

One of the most important features of the Amazon Web Services (AWS) cloud is that the program can be run and accessed from any location. You can access and monitor the result of the program from any location, saving many images and allowing for faster computation. This work proposes a face detection classification model based on AWS cloud aiming to classify the faces into two classes: a non-permission class, and a permission class, by training the real data set collected from our cameras. The proposed Convolutional Neural Network (CNN) cloud-based system was used to share computational resources for Artificial Neural Networks (ANN) to reduce redundant computation. The test system uses Internet of Things (IoT) services through our cameras system to capture the images and upload them to the Amazon Simple Storage Service (AWS S3) cloud. Then two detectors were running, Haar cascade and multitask cascaded convolutional neural networks (MTCNN), at the Amazon Elastic Compute (AWS EC2) cloud, after that the output results of these two detectors are compared using accuracy and execution time. Then the classified non-permission images are uploaded to the AWS S3 cloud. The validation accuracy of the offline augmentation face detection classification model reached 98.81%, and the loss and mean square error were decreased to 0.0176 and 0.0064, respectively. The execution time of all AWS cloud systems for one image when using Haar cascade and MTCNN detectors reached three and seven seconds, respectively.