Al-Qadisiyah Journal for Engineering Sciences

Abstract This study evaluates changes in hardness and estimates the reduction in tensile strength of BJ37 structural steel after exposure to elevated temperatures of 250 ^°C and 500 ^°C using the Leeb hardness non-destructive testing (NDT) method. Since hardness is closely related to mechanical properties, the Leeb test can be used as an indirect approach to estimate tensile strength without damaging the material. A total of 36 specimens were prepared from the flange and web sections of a WF 300 X 150 X 6 X9 steel profile. The specimens were heated to 250 ^°C and 500 ^°C for 15 minutes and then rapidly cooled by water immersion before testing. The initial hardness was measured at approximately 366.19 HL, corresponding to an estimated tensile strength of about 372 MPa. After heating to 250 ^°C, the hardness decreased to 352.5 HL, with an estimated tensile strength of 342.5 MPa; at 500 ^°C, the hardness was 354.7 HL, corresponding to approximately 346 MPa. The reduction in tensile strength ranged from 7.0% to 7.9% relative to the initial condition, with only a small difference between the two temperature levels. These results indicate that the Leeb hardness method can serve as a rapid, non-destructive tool for the preliminary assessment of steel mechanical properties after fire exposure. Further research is recommended to validate these findings through destructive tensile testing, considering a wider range of temperatures, longer heating durations, and a larger number of specimens. The findings provide a practical basis for rapid post-fire evaluation of steel structural integrity.

Abstract Advances in smart materials have made it possible to develop shape-changing wing concepts as alternatives to traditional high-lift systems. In this study, the aerodynamic effects of linear beam extension on a NACA 0015 wing profile with an initial beam length of 150 mm were numerically investigated. The linear actuation mechanism applied along the chord direction resulted in a reduction in the camber ratio. The aerodynamic performance of the conformable configurations was evaluated using CFD analyses conducted under low Reynolds number conditions and employing the k- SST turbulence model. The results indicate that chordwise deformation can improve aerodynamic performance under various operating conditions. This approach offers significant potential for enhancing maneuverability and reducing energy consumption in low-Reynolds-number aircraft, presenting a promising solution for future adaptive wing designs.

Abstract Cancer is still a major health concern, particularly in areas like Iraq with inadequate healthcare systems, where survival rates depend on early and precise diagnosis. Using clinical text data from radiology reports in Mosul, Iraq, this study examines the use of Natural Language Processing (NLP) and Machine Learning (ML) models for cancer diagnosis and classification. In order to categories cancer cases into benign, malignant, stable, progress, and improvement groups, three machine learning classifiers—Support Vector Machine (SVM), XGBoost, and LightGBM—were trained using TF-IDF features on a balanced dataset of 12,923 labelled radiological reports. XGBoost outperformed the other models and showed the highest accuracy (97.25%). This study examines the useful implications for improving diagnostic efficiency and demonstrates the efficacy of NLP-driven machine learning models in healthcare settings with limited resources. The results imply that these ML-NLP models can increase accuracy, decrease the need for manual diagnostic procedures, and possibly offer a scalable solution for healthcare systems with limited funding.

Abstract Natural convection heat transfer in corrugated enclosures has attracted increasing attention due to its importance in thermal management applications. However, the combined effects of wall corrugation, porous media, ethylene glycol–based nanofluids, and magnetic field control have not been sufficiently addressed. In the present study, a numerical investigation is carried out to analyze thermo-magnetohydrodynamic natural convection inside a corrugated enclosure subjected to different heating configurations. The enclosure is divided into two regions: an upper region filled with an ethylene glycol–based nanofluid and a lower porous layer saturated with the same nanofluid. Three heating cases are considered, namely an externally heated corrugated cylinder, an upper heated wall, and an externally heated circular boundary. The governing equations are solved using the finite element method under steady-state conditions. The effects of Rayleigh number (10⁴  up to 10⁶), Hartmann number (0 up to 60), Darcy number (10^-5  up to  10^-3), and magnetic field inclination angle (0° up to 35^o ) are examined at a fixed nanoparticle volume fraction of 0.02. The results show that increasing the Rayleigh number enhances heat transfer, while the magnetic field intensity suppresses convection. Among all cases, the externally heated corrugated cylinder provides the highest thermal performance, and the ethylene glycol–based nanofluid enhances the average Nusselt number by up to 48% at Ra = 10 ⁶.

Abstract This paper presents a technical and environmental assessment of a 3 kWp grid-connected residential rooftop PV system in Al-Diwaniyah, Iraq, using PVsyst 8.0.19. Four scenarios were analysed: monofacial and bifacial PV panels with and without a 5 kWh LiFePO4 battery, plus an expansion sensitivity case using a 10 kWh battery. The battery-free system generated 6,444.8 kWh/year, with a performance ratio (PR) of 80.72%, specific yield of 1,790 kWh/kWp/year, solar fraction of 64.37%, and grid imports of 1,262.2 kWh/year. Adding a 5 kWh battery slightly reduced PR to 77.86% due to charge/discharge losses but increased the solar fraction to 93.00% and reduced grid imports by 80.4% to 247.98 kWh/year. Bifacial panels improved annual production by about 90 kWh/year (+1.4%) and increased PR by 1.13 percentage points in both storage and non-storage cases. Expanding storage to 10 kWh raised the solar fraction only from 93.0% to 96.7%, showing diminishing returns and doubling the cost. Environmentally, the system avoids about 118.4 tCO₂ over 25 years, equivalent to 5,381 trees or removing 25.7 cars annually, with an avoided carbon cost of USD 5,920. The 5 kWh monofacial battery system is the optimal configuration for residential energy independence in the Iraqi context.

Abstract Lake Maninjau, West Sumatra, Indonesia, is under pressure from floating net cage aquaculture, shoreline settlements, agricultural runoff, and domestic activities. This study mapped the spatial distribution of pH and Total Suspended Solids (TSS) using an integrated Geographic Information System (GIS), Ordinary Kriging, and Sentinel-2 MultiSpectral Instrument (MSI) Level-2A imagery. Field sampling was conducted at 30 sites on 18 October 2025, and a cloud-free Sentinel-2 image acquired on 20 October 2025 was processed through Google Earth Engine. The Normalized Difference Turbidity Index (NDTI) and Normalized Difference Water Index (NDWI) were extracted to support spatial interpretation. Measured pH ranged from 5.8 to 8.2, while TSS ranged from 10 to 75 mg/L. Low pH values were concentrated near shoreline settlements and aquaculture areas, whereas high TSS values occurred near agricultural inflows and floating net cage zones. Cross-validation showed acceptable pH kriging performance, with RMSE = 0.896, MAE = 0.628, and R² = 0.755. TSS kriging showed weaker performance, with RMSE = 57.17 mg/L, MAE = 38.94 mg/L, and R² = -0.018. Integration with Sentinel-2 indices showed a strong relationship between TSS and NDTI (R² = 0.84, RMSE = 6.2 mg/L, r = 0.92, p < 0.01), while pH and NDWI showed a weaker relationship (R² = 0.69, r = 0.74, p < 0.05). The results indicate that Sentinel-2 imagery is more effective for optically active parameters such as TSS than for chemical parameters such as pH

Abstract In recent years, drone technology has become very significant in many industrial applications especially for civil infrastructure inspection. In this paper, we present a cascade Proportional Integral Derivative (PID) controller supported by an Artificial Intelligence (AI)-based defect detection system by using You Only Look Once (YOLOv8) algorithm using a drone for civil infrastructure. In conventional inspections, the inspectors are facing difficulties in identifying defects because of old and hazardous buildings, unseen small defects and having substantial safety risks while inspecting high-risk building or bridge structures. This study developed a low-cost Do It Yourself (DIY) drone which was outfitted with a flight controller and First Person View (FPV) camera to capture image in real-world scenarios. The developed AI-based DIY drone system utilized a high-resolution imaging camera which enables rapid and remote data acquisition. During flight testing, the camera captured 60 frames per second of real-time footage while maintaining stable navigation and carrying a payload of up to 800 grammes. The YOLOv8 model trained, validated and tested 6,998 annotated photos, which showed a high mean Average Precision (mAP@0.5) of 99.4%, precision of 96.9%, and recall of 98.4%. The results ascertained that the system can reliably identify structural flaws like cracks, corrosion, peeling paint, and water seepage in difficult environmental conditions.

Abstract The most lethal form of skin cancer is malignant melanoma; however, it is highly curable when detected at an early stage. Despite the exceptional diagnostic capabilities of Deep Convolutional Neural Networks (CNNs), it is essential to select the appropriate architectural paradigm in order to achieve the highest clinical safety, the lowest computation cost, and the best predictive performance. This investigation comprehensively evaluates the binary classification of dermoscopic images using five distinct pre-trained CNNs (SqueezeNet, GoogleNet, ResNet-50, MobileNetV2, and EfficientNetB0) and a variety of structural paradigms. A balanced dataset of 9,605 images was utilized alongside transfer learning, stochastic spatial augmentations, and an optimized Adam-based training protocol. To achieve consistent predictive stability (Accuracy = 90.94% ± 0.13%), EfficientNetB0 was tested using a 5-Fold Cross-Validation protocol, and the rest of the networks were tested using hold-out method with minimal computational burden. These findings of the quantitative analysis have illustrated that the clinical compromises of the architectures were diverse. The Area Under the Curve (AUC) and Specificity (98.40%) values of ResNet-50 were the highest, suggesting that it effectively reduced false alarms. On the other hand, GoogleNet, by emphasizing patient safety, obtained the highest Sensitivity (90.80%). Additionally, the SqueezeNet micro-architecture was capable of preventing class-collapse as a result of the optimized training process, which resulted in an increase in accuracy to 91.40%. This was critically important. The findings of this study indicate that deep residual networks are the most appropriate for high-precision screening, while the deployment of lightweight networks of a suitable scale is highly viable and reliable in computational environments with limited resources.

Abstract This study experimentally investigates the effect of hydrogen enrichment on combustion characteristics, engine performance, and exhaust emissions of a four-stroke spark-ignition (SI) gasoline engine. A single-cylinder, 0.61-L, air-cooled engine was operated at 2300 rpm under full load with hydrogen blending ratios of 5%, 10%, 15%, and 20% by fuel energy, using unleaded gasoline (RON 95) as the base fuel. Hydrogen was delivered through a dedicated port injector upstream of the intake valve. Peak cylinder pressure increased by 17.6% (4.82 to 5.67 MPa at H20%), and the 10–90% mass-fraction-burn duration decreased by 31.6% (38 to 26 °CA), driven by hydrogen’s high laminar flame speed (237 cm/s) and wide flammability range (4–75 vol%). Brake thermal efficiency peaked at H15% (32.1%, +12.6%), while brake-specific fuel consumption fell by 17.35% at H20%. Combustion stability improved by 60.7%, with COV of IMEP reduced from 2.8% to 1.1%. CO, HC, and CO₂ emissions decreased by 81%, 66.5%, and 25%, respectively, with the average unburned-HC carbon chain length reduced from C₆.₂ to C₃.₁. However, NOx emissions rose by 338.7% due to higher peak combustion temperatures activating the thermal (Zeldovich) mechanism. The optimal blending ratio is 10–15%, balancing efficiency gains against NOx penalties addressable through established aftertreatment strategies.

Abstract The behavior of reinforced concrete (RC) members with glass fiber reinforced polymer (GFRP) bars has been the focus of several studies in previous years. However, a study to investigate the behavior of reactive powder concrete (RPC) columns reinforced with GFRP bars (GFRP-RPC) has not been conducted. This study aimed to study the structural behavior of circular columns fully reinforced with GFRP bars and hoops or spirals. In the present study, the behavior of GFRP-RPC circular columns under axial load is studied with the effect of four variables: longitudinal reinforcement ratio, transverse reinforcement ratio, transverse reinforcement configuration (hoops vs. spirals), and type of longitudinal reinforcement (GFRP, steel, and hybrid). Twenty circular columns with a diameter of 150 mm and a height of 1000 mm were cast and tested, divided into seven groups. Results discuss failure modes, axial load capacity, deformations (displacement and strains), and ductility. Test results indicate that the load capacity of the columns increased by ranging from approximately 46 to 56.25% when the longitudinal reinforcement ratio increased from 1.77 to 3.55%, also increased the transverse reinforcement ratio from 1.24 to 2.48% enhanced the load capacity ranging from approximately 5.13 to 19.1%. Moreover, the nominal capacity of GFRP-RPC columns was compared with the design equations so, the results were verified.

Abstract Most industries struggle with corrosion. Corrosion inhibitors are needed in these sectors. Eco-friendly corrosion inhibitors should be effective even at low concentrations. In this work, the compound 2- Fluorophenyl-2, 5- dithiohydrazodicarbonamide (2F-TSC) was utilized as a corrosion inhibitor for copper in a 3.5% NaCl solution. The inhibitor efficiency was calculated by using a series of electrochemical methods like, open circuit potential (OCP), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). All tests have been done in a stagnant condition. The results show that the compound 2F-TSC looked to be of mixed type. Furthermore, the maximum inhibitor efficiency was reached at 99.2% at 10^-2 M 2F-TSC and 5 h. The adsorption of 2F-TSC on the copper surface in 3.5% NaCl obeyed the Langmuir isotherm with a negative value of the standard Gibbs free energy of adsorption of -35.4 kJ/mol (chemisorption and physisorption). SEM, EDX, and AFM confirmed the presence of 2F-TSC on the surface of copper. The adsorption of the inhibitor molecules on the Cu (111) surface was further verified by a Monte Carlo simulation study. The results approved that the 2F-TSC can be utilized as a corrosion inhibitor for copper in an aggressive solution (3.5% NaCl).

Abstract This study aimed to investigate the heat transfer behavior of an Al₂O₃-water nanofluid within a coil-agitated tank. The experiment utilized Al₂O₃-water nanofluids with varying volume concentrations, namely 0.2 vol%, 0.3 vol%, and 0.4 vol%. Two different cooling water flow rates, specifically 1.8 and 2.2 liters/min, were employed during the investigation. The propeller speed ranged from 2 to 12 (rps), and the temperature spanned from 30 to 80 °C. The findings revealed that the heat transfer coefficient of the nanofluids exceeded that of the base water. Moreover, it increased with higher volume concentrations, reaching its peak at 0.4 vol% with an average rise of approximately ±77.2%. Additionally, the heat transfer coefficient demonstrated an increase of about ±19.8% when the temperature was elevated to 80 °C and approximately ±11.9% when the propeller speed was raised to 12 rps. Comparing the two distinct flow rates, it was observed that the heat transfer coefficient rose with decreasing flow rate to 1.8 liters per minute, exhibiting an average enhancement of approximately ±13.6%.

Abstract Numerical investigation of mixed convective in a vented square cavity with fin. The horizontal walls are adiabatic, while the left and right walls are at hot and cold temperatures, respectively. The fluid inlet to the cavity from the lower left open area, and exit from the upper right open area. In this study, a finite element scheme is employed. The analysis is done for specific Prandtl number, Reynolds number, fin length, Richardson number, and the location of the fin. The finding indicates that the increases when high the location of the fin is, the increase at the maximum height of this fin location is estimated to be 17% due to an increase in the area of fluid flow on the hot wall caused by rising convective. The highest heat transfer occurs when the fin length is equal to 0.6 at the location.

Abstract This paper presents a proposal for an authentication scheme for smart building systems and environments based on blockchain, its positive features, and fog computing. The most important feature that can be distinguished in the submitted proposal is its adoption of the principle of decentralization in contrast to traditional centralized documentation protocols, i.e. the proposed authentication system in which users and smart devices are implemented in a distributed and decentralized manner on the blockchain,  that will provide a solution to a significant problem of low overall efficiency of the authentication process caused by a bottleneck in such important areas as computing capacity as well as centralized storage of a single authentication authority in the traditional model. There are also benefits from adding fog computing, and because it has higher computing and storage capabilities, it makes the data processing process more efficient, faster, more streamlined, and in line with the common necessities of the real-time IoT environment. The proposed scheme also provides solutions to protect the privacy of user data and increase the level of confidentiality, protection, and security, since a mysterious extractor was used to increase the confidentiality of the proposed model of the authentication system. Comparing a set of security schemes and conducting a security and performance analysis of the proposed scheme, the comparisons showed that the scheme can be characterized as having a good security level and an important efficiency level. The paper focused on specific aspects design of the authentication system, such as the registration and authentication process of all network entities, regardless of the specifics of the implementation of blockchain smart contracts.

Abstract The column is considered as a support rooted in the ground and forms the part responsible for connecting the upper and lower level. It is a dialectic duality to provide the space with its required qualities .It is a base to support what lies above it and forms a poetic vision which hypothetically give the identity of the place .It forms a constituent in Arabic Islamic architecture worthy of comprehensive of its significance; and explore the various faces in the civilized heritage of the nation distinguished in its architectural character in terms of functional, aesthetical, historical and moral symbolism . In this content, the column provided a typological architectural expressions in palaces, temples, masjed, caravansaries , public baths , markets ...etc. Which formed the total urban forms in the history of this land . The most significant type of columns in Arabic architecture is the Baghdadi ( the delegue) and andelosian columns . The “research problem” represent in the ambiguity and shortage, detection, dimension and connotations implications that accompanied a column in the Arab-Islamic architecture.The research aims to detect the different dimensions and connotations of which was accompanied by the emergence of the column. The results of research to reveal the dimensions and connotations of the different that accompanied the emergence of the column in the Arab Islamic architecture, which is the connotations of structural, historical, aesthetic, spiritual, religious, social, philosophical and symbolic, educational, environmental and urban, formal and expressive content timer as well as the connotations of heritage.

Abstract Traffic crashes are one of the main reasons for the death of many people and the loss of property Therefore, it is important to conduct research and studies to reduce the risk of accidents and identify the causes that lead to their occurrence. The condition of the pavement is one of the main factors that lead to accidents, as several studies have been presented that show the impact of pavement defects such as rutting, roughness, and skid resistance on traffic safety. This research was conducted to find out and compile the most important research papers using the web of science (WOS) and then analyzing the data using the VOSviewer program, and to know the most countries and journals published on the related pavement condition of road crashes, as well as to know the authors and their cooperation. In addition to knowing the keywords that help researchers research this topic. In order to benefit from these studies in knowing the causes of accidents, analyzing and treating them, and improving the performance of roads using modern analysis and maintenance methods that ensure traffic safety.