AL-Rafidain Engineering Journal (AREJ)

Drip irrigation is important in rationing the use of irrigation water, especially in arid and semi-arid regions that suffer from a severe shortage of water resources. To estimate the volume of the wetted soil under drip irrigation, twelve laboratory experiments were conducted to track the advancement of the wetting front during certain times for the wetting phase and the moisture redistribution phase as a result of adding water from two linear drip sources. Three spacings between the emitters (30, 40, 50) cm were considered for a layered soil consisting of two soil textures: one with clay over sandy loam, and the other with sandy loam over clay. Two rates of discharge (0.956 and 1.515 cm3/min/cm) were considered. The data were represented by empirical relationships to estimate the wetting pattern in the horizontal and vertical directions and in the middle of the spacing between the two emitters, with a determination coefficient of 0.96, 0.98, and 0.97, respectively. It was observed that the wetting pattern increases with a decrease in the interval between the drippers, and that this increase is regular along the wet perimeter, and this increase is greater in the vertical direction than in the horizontal direction, and for both soil profiles. In addition, an increase in water application let to increase the vertical progression, as it is greater in the case of soil profile (sandy loam over clay), while the horizontal progression is clear for the soil profile (clay over sandy loam).

The three-phase separator, a cornerstone of oil and gas production, is pivotal for maintaining high-quality oil output and minimizing environmental impact. Efficient separation of water, oil, and gas ensures superior oil quality and economic viability by removing impurities and contaminants from the extracted mixture. Moreover, the environmental significance lies in preventing contamination of water bodies through proper disposal of produced water. This review paper presents a comprehensive investigation on the simulation of three-phase oil separators utilizing Computational Fluid Dynamics (CFD) analysis. The emergence of CFD as a powerful tool has revolutionized separator design by unraveling complex flow patterns and interface structures. CFD aids in understanding turbulent flow structures resulting from inlet diverter interactions, leading to enhanced separation efficiency. This innovation reduces design costs by allowing engineers to simulate various configurations, resulting in optimized separator designs. Essential design parameters encompass oil properties influencing separation behavior, the design of the inlet diverter affecting flow dynamics, mean residence time for phase separation, separator diameter determined using techniques like Monner and Svrcek or Arnold and Stewart, weir height for phase interface control, and droplet size and distribution which significantly impact separation efficiency are also covered in this work.

The population increase and construction development witnessed by the world in recent years and the exploitation of areas that may have unsuitable soil for constructing high rise buildings. Hence, it is necessity to develop a special type of foundation that can withstand large static and dynamic loads. The piled raft foundation system that depends on the soil-piles-raft interaction phenomenon is very important which was developed to increase the load carried capacity and reduce the settlement. Many types of weak soil are considered to be problematic which should be taken into consideration in geotechnical engineering. Therefore, the researchers studied the behavior of the pile raft system by experimental and numerical methods under static and dynamic loads to understand the mechanism of the load sharing between the foundation compositions as well as to reach the safe design regarding bearing load and settlement

An identity verification and identification system based on a person\'s distinctive vocal characteristics is known as speaker recognition. This paper sheds light on the evolution of speaker recognition systems from the earliest days of computers to the most recent innovations. Voice represents the behavior biometric that communicates details about a person\'s features, ranging from the speaker\'s age, gender, and ethnicity. The field of speaker recognition focuses on identifying individuals by their voices. Even though speaker recognition has been the subject of research for the past eight decades. Applications such as the Internet of Things (IoT), smart homes, and smart gadgets have made their use fashionable in the modern era. The speaker recognition field is briefly discussed in this work with an outline of its modeling methodology and various feature extraction strategies across multiple languages. The aim of this speaker recognition literature is to advance academic knowledge of speaker recognition

This study investigates the resistance of high-strength concrete (HSC) to sulfuric acid exposure, focusing on its application in constructing floors in acid storage plants, sewage manholes, and other areas exposed to acid. The aggressive chemical attack from acids poses a significant threat to concrete durability and strength. The study also examines the effect of supplementary cementitious materials (SCMs) on enhancing the resistance of HSC to acid attack. Six HSC mixtures were evaluated: two control mixes, two mixes contained 25% cement replacement, one using fly ash Type-F and others using slag. Three mixes have been cured in water for 3 days, while others have been cured in water for 28 days. All mixtures were immersed in a 3% sulfuric acid solution for a period of 28 or 56 days. To assess concrete deterioration, compressive strength, tensile strength, and weight loss were measured. The study demonstrated that exposure to sulfuric acid caused significant surface erosion on HSC. All HSC mixtures experienced strength loss, especially the control mix. The presence of slag enhanced the acid resistance of HSC, particularly for the 3-day cured specimens. While the presence of fly ash enhanced the acid resistance of HSC for the 28-day cured specimens.

Image transmission in modern communication systems needs fast and low error coding and imperative transmission mechanisms. For engineers, dependable communication over a noisy channel is a long-standing but difficult problem. One of the important types of channel coding is Low-Density Parity-Check (LDPC) codes which are considered Linear Block Codes (LBC). Due to their superior error-correcting ability, LDPC codes are among the most widely used Forward Error Correction (FEC) codes. The purpose of this paper is to create transmitter channel encoder LDPC architectures and the corresponding channel decoder in the receiver for image transmission. The study integrates the Effective Encoding of the LDPC codes algorithm for the encoder and the Bit flipping LDPC codes algorithm for the decoder, Vivado HLS (High_Level Synthesis) is the tool utilized in this work, The HLS loop unrolling optimizing technique is used to give the synthesizer instructions on how to implement a particular code section, the designer can quickly and easily optimize the application, as a result, optimization is done directly on the source code. Additionally, it suggests applying optimization techniques like loop unrolling to every design. C programming language and HLS are used to create all architectures.

This study investigates the impact of temperature and pressure on friction welding, a solid-state joining technique. It uses simulation to analyze material behavior and properties during the welding process. The study aims to optimize welding conditions to improve joint strength and integrity. The results provide recommendations for maximizing parameters in practical applications, enhancing production procedures and enhancing decision-making. The simulation-based methodology also offers an economical and expedient method for investigating situations before experimental execution. The test rod, measuring 16mm in diameter and 100mm in length, was designed for two pieces. The simulation program was set up with timings and pressures, a fixed rotation speed of 1500 r.p.m., and the temperatures from the welding process were entered into an artificial intelligence SIMULIK program. The study reveals that the deformations of the materials being welded are directly influenced by the welding pressure. Greater force is given to the materials as pressure rises, which causes more plastic deformation. and longer times under frictional pressure can lead to higher temperatures due to increased heat generation from friction. This enhanced metallurgical bonding can result in a joint with improved fatigue strength. which can contribute to better fatigue resistance. Prolonged welding pressure helps in reducing stress concentrations at the weld interface. and the stress distribution will be more uniform, minimizing the likelihood of stress concentration points in the weld joints with fewer defects and improving resistance to crack initiation and propagation.

It is common in architectural conservation organizations that some conservation knowledge is not frequently provided. This calls for the necessity to access external sources of knowledge. This paper aims to investigate the current situation of managing the external knowledge in the context of the Management of Historical Cities Bureau in Tripoli, Libya, in order to develop a theoretical framework that can function as a procedural guide for acquiring external knowledge in such organizations. Qualitative research for collecting and analyzing data was adopted. Multiple methods were used for collecting data, including interviews, observations, and a review of organizational documents. The findings demonstrated that there is insufficient information regarding local experts and current interaction with consultants is based on an ad hoc method that does not ensure that technical experts respond in a timely manner. Also, there is insufficient knowledge exchange with relevant local organizations. Furthermore, legal, and political reasons obstructed the process of acquiring knowledge from foreign organizations. Finally, this research and the proposed framework for acquiring external knowledge in architectural conservation organizations provide a base reference for similar organizations in developing countries that intend to manage external knowledge that contributes to the process of conserving historic buildings and improving their performance.

In the realm of wireless communication, ensuring end-to-end privacy remains a critical concern in real-time applications like Autonomous Vehicles (AVs). The existing wireless protocols often need to be revised to address these privacy challenges effectively, especially when sensitive data transmission is involved. To tackle this challenge, this paper proposes a unique solution tailored to the specific requirements of each AV through the establishment of individual wireless network domains. To bolster privacy and security, a new approach called resilient modulation is introduced. This method involves integrating the Vehicle Identification Number (VIN) into the Complementary Code Keying (CCK) equation within the 802.11b network. Additionally, the proposed enhancement extends to the Wireless Controller Area Network (CAN) bus, introducing an added layer of security. Furthermore, modifications are made to the conventional CCK modulation scheme to accommodate the proposed enhancement seamlessly. By adjusting the phase angles of transmitted signals, the integrity of the CCK modulation scheme is maintained, preserving orthogonality and correlation that are crucial for effective communication. Through rigorous experimentation and analysis, The results showed that the Bit Error Rate (BER) and packet loss of the receiver Electronic Control Unit (ECU) were stable between different CCK modifications. This indicates the robustness of the basic features of CCK modification and that the extent of modifications does not affect the CCK modification scheme with respect to orthogonality and correlation properties. On the contrary, there is a significant challenge in intercepting and decoding the signal by the eavesdropping ECU, which has shown packet loss ranging from 63% to 100% across different CCK states.

Rainwater collection has long been recognized as an efficient method for increasing agricultural output in dry and semi-arid settings. It contributes to the expansion of green spaces in such regions, the improvement of water levels in groundwater wells, the reduction of floods, and the resolution of sewage issues. The primary aim of the present study is to identify difficulties that directly impact the water harvesting process, such as soil type and surface topography, which will help us understand the value of infiltration and, as a result, the volume of water collected. The findings indicate that utilizing rainwater in buildings has a large potential for producing drinking water. Studies estimate that it is possible to supply 20% to 65% of household and agricultural drinking water. Furthermore, using technology would improve the efficiency of rainwater harvesting systems by finding appropriate surfaces for rainwater collection and limiting the consequences of floods in metropolitan areas. There is still much to learn about the benefits of water harvesting dams from a variety of viewpoints, and more study is needed on the effects of climate change on their performance over time and the best approach to managing them under present conditions, particularly in Iraq.

The retina is susceptible to numerous diseases, and cataracts are most prevalent, especially in developing nations. Cataracts are recognized as one of the most impactful diseases affecting the retina, given their propensity to develop asymptomatically and potentially lead to blindness or impaired vision among the elderly. Timely detection of cataracts and appropriate intervention is pivotal in mitigating disease progression and reducing instances of blindness attributable to this condition. This study provides a deep learning system based on parallel architectures, that utilized a proposed deep convolutional neural network (DCNN), to detect and diagnose cataract disease accurately. ODIR dataset was used for training and validating the proposed model, which achieved 97.7% accuracy for cataract detection, with an inference time of no more than 0.06 sec.

GaN devices are appropriate for power applications because of the unique material features of GaN, which provide GaN HEMTs with low R_on and high breakdown voltage (VB). Field Plates (FP) are used to improve the efficiency of a conventional HEMT for power applications while maintaining the device's dimensions. Field Plate (FP) technology has been shown to improve HEMT power performance significantly. The HEMT's break-down voltage has been increased as part of the improvement. Therefore, using Silvaco-ATLAS two-dimensional simulation, the principle and compute performance of the standard HEMT and the HEMT with the field plate (FP) have been explored in this paper. The results obtained may lead the path to an improved and efficient approach to the production of high-power devices that can be used in power electronics applications. The breakdown voltage of the device rises from 44 V of the device without FP to 125 V at SFP, 402 V at T-Gate, 429 V at both GFP and SFP and finally to 515 V at GFP by choosing the right field plate structure and field plate length. The result shows an excellent ability to improve the GaN HEMT for power applications by using different types of field plats without increasing the dimension of the simulated device. Also, the single-peak of the electric field is replaced with multi-peaks and the distribution of the electric field will be uniform by using a field plate.

This study evaluated the effects of acrylonitrile- butadiene- styrene (ABS) polymer on the paving mixtures made with calcium carbonate (CaCO3) as a common filler and Blowdown (B) waste as a sustainable filler. Both mix-tures, Unmodified and ABS-modified containing both fillers were subjected to Marshall stability (MS), Marshall Quotient (MQ), tensile strength (TS), tensile strength ratio (TSR), cracking tolerance index (CTindex) and deformation strength (DS) in Kim tests. Statistical analyses of the results show that a B-mixture owned higher MS and DS, with lower TSR and CTindex than CaCO3 mixture, while ABS modified-B mixture depicted higher marshall stability, cracking and fatigue re-sistance with lower moisture, rutting resistance comparable to the ABS-modified CaCO3-mixture. In addition, B-mixture is a cost-effective solution and eco-friendly than CaCO3 mixture for pavement application since its properties located within the specification's limits.

The research included a practical and theoretical study on a PV/T collector to verify the validity of the results and data provided by the simulation program used in the research (TRNSYS). A practical PV/T collector was designed and implemented, followed by theoretical simulation using the (TRNSYS) program. Comparitive analyses of the practical and theoretical results of both closed cycle and open cycle systems was conducted under the atmospheric conditions of the Mosul, Iraq. The solar collector was faced the south, and comprehensive data form the practical setup were recorded after its operation. For the closed cycle, the results showed an error of 2.7% in the exit water temperatures from the solar collector and a 3.4% error in the tank water temperature. In the open cycle, an error of 2.8% was recorded the incident radiation intensity, with 3% error in the solar collector’s thermal efficiency. The close difference of these results confirms the accuracy of the data provided by the TRNSYS program, indicating its reliability for developing and studying other theoretical systems, thereby saving time, effort and money

The majority of acoustic signals contain additive reverberation noise, which degrades and distorts the reliability of the sound system and has detrimental effects on a variety of identification applications, including the speaker recognition field. This paper analyzed two techniques to mitigate and combat the impact of reverberation on sound and compared the performance of these methods. These techniques are Mel-Frequency Cepstral Coefficients (MFCC) and Gammatone Frequency Cepstral Coefficients (GFCC). The GFCC differs from the conventional MFCC in that it replaces the Mel filter bank with a Gamatone filter bank to increase durability.
To avoid the effects of environmental sounds and different features of the speaker voice duo to the variable situation of the speaker such as illness and emotion, a single tone of 1 KHz was applied to obtain a fair and impartial comparison between the GFCC and MFCC methods of sound signal recognition.
The comparison between the MFCC and GFCC features was accomplished by using PCA and corroborated by the normalized cross-correlation NCC. Reducing dimensions and removing correlation is the primary purpose of the PCA algorithm so that the features become orthogonalized. The PCA and NCC report that for both reverberant and non-reverberant single-tone recorded sound, there was a about 10% increase in the rate of detection and the variance increased by 11% for GFCC compared to MFCC features.
Then this work shows that method uses GFCC features is stronger and superior against the reverberation noise than classic MFCC features. Therefore, the GFCC mitigates the reverberation effect and presents a good candidate for functionality in actual recognition systems. In addition, this work examines the potential outcomes of joining the MFCC and GFCC as feature components to obtain a more robust speaker recognition system. The imrovment in the obtained variance is demonstrated by the results to be roughly 30% greater than in the case of GFCC feature coefficients variance.