In large office buildings and commercial complexes, HVAC systems account for nearly two-thirds of total electricity consumption. However, early fault detection and diagnosis (FDD) in water-cooled chillers remains challenging because faults usually develop slowly, produce weak initial signatures, and exhibit strongly nonlinear thermodynamic behavior. Moreover, overlapping operational characteristics between faults make accurate diagnosis under mild and moderate conditions difficult. Previous studies using the ASHRAE RP-1043 dataset reported limited diagnostic performance for incipient faults, particularly refrigerant leakage and condenser fouling. To address these gaps, this study proposes a hybrid optimization-based FDD framework for early fault diagnosis in water-cooled chillers, integrating the Non-Dominated Sorting Genetic Algorithm III with Local Search (NSGA-III-LS) and the M5 Prime regression model for hyperparameter tuning and nonlinear operational modeling. The proposed framework offers a balanced trade-off between fault sensitivity, residual stability, and diagnostic accuracy. Validation results demonstrate high detection rates of 62.5-95.83% for mild faults and nearly 100% for severe faults, outperforming conventional methods, especially during incipient fault stages. The proposed method also supports earlier detection of abnormal thermal behavior, contributing to energy savings of approximately 15-30%, extended equipment lifespan, and more effective predictive maintenance planning.
Hybrid polymer composites are an essential part of modern production. Polymer composite structures may encounter diverse corrosive environments during their operational lifespan, resulting in structural degradation and a decline in their inherent properties. This study examines the impact of using various volume fractions (1%, 2%, and 3%) of beryllium oxide (BeO), which is also known as beryllia, nanoparticles on the mechanical properties of carbon fabric-reinforced epoxy composites in both acidic and alkaline conditions at different exposure times. The investigation focuses on the toughness, tensile features, and hardness values of the prepared hybrid composite before and after immersion in hydrogen chloride (HCl) and caustic soda (NaOH) solutions. Irrespective of the solution type, exposure over time reduces the hardness, tensile strength, and impact strength. Notably, the alkaline solution induces a more pronounced decrease in these features than the hydrogen chloride (HCl) solution. Furthermore, BeO nanoparticles result in a noteworthy enhancement in the mechanical performance of these hybrid composites against these solutions.
There are many applications of hydraulic systems used by lifting mechanisms. It is one type of pressure-control valve. Its function is to balance the lifting forces to reduce power consumption, manually adjust to a specific pressure, and provide an equivalent load. This work aims to investigate the control performance between the valve and the sensor. An automated system is proposed that controls a proportional pressure relief valve, load cell, and pressure sensor via a programmed controller. In a way that keeps the variable load actuator in its position regardless of the value or time of its load pressure. verify the function of the system, it was simulated using FluidSim software V4.2. When a certain weight is lifted, we get variables such as valve pressure, cylinder position, speed, and sensor voltage output. A laboratory crane was also used to test the system. This is to verify the performance in the laboratory. The error values were (5.01, 4.39, and 2.29) at pump pressures (5, 10, and 15 bar), respectively. As a result, the system's work and performance are acceptable.
In the distinct geotechnical landscape of Al-Karkh, Baghdad, ensuring the structural robustness of underground reinforced concrete beams is imperative. This work delves into the potential advantages of integrating steel fibers and steel meshes into these beams using three types of concrete: Normal Strength Concrete, Sulphate Resistance Concrete, and Reactive Powder Concrete. Instead, it employs Type V Portland cement, known for its sulfate resistance. This study analyzes their load-carrying capacity and deflection behavior. Initial outcomes suggest that beams reinforced with Steel Fiber and Steel Mesh exhibit enhanced load-bearing capacity, reduced deflection, and improved resilience to environmental stressors. The integration of both Steel Fiber and Steel Mesh will increase the ultimate load of Normal Strength Concrete, Sulphate Resistance Concrete, and Reactive Powder Concrete by 55%, 69%, and 119% respectively. Significantly, the presence of steel meshes was linked to augmented beam strength. This work underscores the potential structural benefits of Steel Fiber and Steel Mesh. In addition, using Portland cement Type V in Reactive Powder Concrete is possible, emphasizing the applicability in urban underground frameworks, especially in contexts mirroring Al-Karkh's conditions.
This paper presents the utilization of a half-mode substrate integrated waveguide (HMSIW) cavity loaded with a meandered slot line (MSL) to design a miniaturized a 2nd order tri-band bandpass filter (BPF). The MSL was employed to independently control the operating passbands and to reduce the filter size. A systematic design procedure was used in this work to systematically calculate the theoretical parameters. Ansys EDT and ADS simulators were adopted to design and optimize the proposed structure and validate the achieved results. Simulation results showed that the proposed filter occupies an area of 0.041 at 4.7 GHz acquiring a compact size. Simulation results showed that the optimized structure operates with three passbands centred at 4.7 GHz, 7.28 GHz, and 9.36 GHz with insertion losses of 0.23 dB, 0.77 dB, and 1.8 dB, and the return losses of 20 dB, 19 dB, and 18 dB, respectively. The achieved findings showed that the proposed filter is compact and exhibits superior performance, which makes it well-suited for emerging multi-functionality wireless communication applications. The filter's size reductions and tri-band functionality make it a particularly desirable option for integration within miniaturized communication systems.
The distribution of rainfall in dry areas, such as Iraq, is extremely erratic. The rainfall is mostly limited to occasional, intense, and unpredictable storms with high surface runoff and uncontrolled gullies and rills flowing on soils with low infiltration rates, and then it is collected at the end in wadis. Thus, most of the rainwater is lost as evaporation if not harvested. The objectives of this work were to explore the promising water harvesting areas of the Tigris River Basin (TRB), evaluate the amount of harvested rainwater from the river basin in Iraq, and then how to improve rainwater use efficiency. The GIS technique was utilized to examine the hydrological characteristics of the basin and locate the rainwater harvesting sites. The volumes of the harvested water (runoff) were assessed utilizing the SCS-CN method. The results showed that about 70% of the river basin inside Iraq is suitable for rainwater harvesting with a total annual runoff of 324 BCM. The results demonstrated that the harvested rainwater use efficiency ratio increases with the increasing amount of the used water or the relative water protectivity per unit area. The paper presented some suggestions and recommendations for improving rainwater use efficiency in the catchments of the TRB within Iraq.
One of the longstanding problems in digital imaging is the compression of images with sufficient fidelity for reconstruction. Common file formats like JPEG and PNG are not well suited for higher compression, so there has been a growing interest in compressive sampling as an alternative. In this paper, the basic principles of compressive sampling are appraised, and its performance is compared with traditional methods of compression on a set of 129 animal images. The compression ratios of the Sparse Transform method on the test dataset were within the range of 9.26–93.44 (mean 45.02). Mean reconstruction error was 24.14, PSNR ranged from 18.98 to 27.07 dB (mean 23.27 dB), and SSIM from 0.68 to 0.96 (mean 0.85). The results presented here indicate that, among the compressive sampling variants tested, the Sparse Transform approach rose as the best combination of compression and reconstruction quality, whereas the conventional methods (including JPEG) have better reconstruction fidelity at each operating point. Finally, the paper raises a number of questions that need to be addressed in order to continue work in this area, particularly the applicability of the method to other more specialized imaging tasks.
Smart home technology provides the ability for homeowners to remotely monitor and control home appliances by connecting them to the internet. Despite its benefits, many people around the world are reluctant to adopt smart devices into their home for security reasons. Namely, connecting smart homes to the internet opens an attack surface for hackers to gain access and possibly control the smart home. Also, most smart home devices have low computational power and therefore cannot provide complex security protocols. In that case, to achieve the goal of remote user authentication, this paper proposes a 2-factor authentication scheme that consists of local biometric authentication and remote authentication with user identity and a time-based one-time password (TOTP). The security of the scheme is validated with formal and informal security checks. The proposed system outperforms similar systems since its computation overhead is (0.02 ms) and its communication overhead is (416 bits). A possible avenue of future work may involve using this authentication scheme in wider IoT applications such as wireless sensor networks.
The study was conducted on an urban roadway segment in Lima, Peru, characterized by high levels of traffic congestion. The objective was to evaluate the implementation of a road diet strategy with the incorporation of micromobility corridors. Unlike previous studies, the roadway serves a dual urban and interurban function, connecting Lima with cities in the central region of the country, resulting in more complex operating conditions and critical Level of Service (LOS F) conditions. Initially, the existing conditions were modeled, and subsequently, a geometric redistribution of the roadway was proposed. The intervention does not involve the conventional lane reduction (4 to 3 lanes), but rather a functional reconfiguration that increases operational performance, increasing from 4 to 5 effective lanes and incorporating 2 exclusive side lanes for micromobility. Both scenarios were microsimulated in PTV Vissim, with calibration using the Wiedemann 74 car-following model and validation through metrics such as MAPE and GEH. The results showed improvements in Level of Service from F to D, as well as reductions in travel time, although queue delay increased, exceeding the results reported in previous studies. The road diet significantly improved roadway performance under high congestion and complex functional characteristics.
This paper presents a reconfigurable quad-element frequency-MIMO antenna designed to work at sub-6 GHz and 38 GHz of the fifth generation (5G) spectrum. The proposed design uses orthogonal radiating elements to provide more isolation (>15 dB) and pattern diversity. The antenna is fabricated on a Rogers RT/Duroid 5880 substrate with dimensions of , a loss tangent of 0.0009, and a dielectric constant of 2.2. Switching between the far diverse bands of 5G communications using a MIMO reconfigurable antenna is a significant way of this work aims to perform. The RLC equivalent circuit's ON/OFF response determines two types of PIN diodes used that perform differently. Diodes used in mid/high-frequency 5G bands are evaluated to choose the best of the target frequencies. According to CST simulations, SMPPSC79 diodes function best at 5.15 GHz with (4.58-6.45) GHz bandwidth running, and MACOM MADP-000907-14020 diodes perform best at 38 GHz with (36.2-39.6) GHz operation bandwidth. High performance is obtained with a diversity gain of 9.8 and an envelope correlation coefficient of less than 0.04. Additionally, the Antenna peaks at a gain of 6.14dB and a total efficiency of 87% in the two frequency bands. These results suggest that the frequency-reconfigurable MIMO antenna is suitable for 5G applications.
Outdoor thermal comfort (OTC) has become a crucial topic, particularly due to global warming and growing public interest in outdoor tourism. This study evaluated OTC conditions at Lampuuk Beach, Aceh Besar Regency, Indonesia, using field measurements of climate parameters and a visitor thermal perception survey conducted over three days in May 2023. A total of 288 respondents participated, while air temperature, relative humidity, wind speed, and solar radiation were simultaneously recorded. The findings indicated that most visitors experienced moderate-to-severe heat stress, with thermal sensation ratings predominantly ranging from warm to hot. Nevertheless, more than 50% of respondents considered the conditions acceptable or comfortable, suggesting relatively high thermal adaptation to tropical outdoor environments. Among the evaluated parameters, air temperature was the dominant factor influencing thermal comfort indices. Physiological Equivalent Temperature (PET) showed a stronger correlation with thermal sensation and Predicted Mean Vote (PMV) than Universal Thermal Climate Index (UTCI), indicating its suitability for assessing outdoor thermal comfort in tropical coastal environments. The findings highlight the thermal tolerance of people living in warm-humid climates and provide useful insights for improving outdoor thermal comfort in tourism areas under rising temperatures.
The present study includes the behavior of reinforced concrete columns under elevated temperature. Four specimens of columns were cast for this purpose, with a constant length of 540 mm and a constant sectional area of 100×100mm, with a curing time equal to 28 days. Then, the specimens are exposed to elevated temperatures (150, 300, and 600 °C) and to room temperature. After air-cooling, the specimens are examined as hinged-hinged supported columns with a point load applied at the top of the column. The ultimate load capacity, mid-lateral deflection, mid-axial displacement, failure mode, and crack formation are investigated. The results indicate an appreciable effect on the strength of columns caused by exposure to high temperatures, which is greater than 300 °C, where a decrease in the value of ultimate load is observed when subjected to a temperature level of 600 °C, where the ultimate load becomes 35.2% of the original value. Additionally, the specimens exhibit large deformation under extreme temperatures, resulting from a substantial drop in column stiffness; the stiffness of the column heated to 600 °C decreases by about 55.5% relative to that at ambient temperature.
The current study focuses on the utilization of tangerine peels, a major agricultural waste generated by consuming this fruit, as a low-cost adsorbent for removing pyridine from contaminated aqueous solutions. The adsorption performance was assessed through batch adsorption tests conducted under various operational conditions. The study reported that tangerine peels had a high capacity for the removal of pyridine, the maximum pyridine removal efficiency reached 83.6% under optimized operating conditions, including an adsorbent dosage of 5.8 g, pH 6, agitation speed of 400 rpm, and contact time of 150 min, where efficiency increased as agitation speed, adsorbent dose and contact time were raised, but decreased with greater values for other variables. pH left runs with pyridine removal both increased in the acidic range to pH 6; however, they decreased under neutral and alkaline conditions. Morphological study indicated that the surface area reduced from 16 to 3.25 m²/g after adsorption of tangerine peels. The occupation of active sites and depletion of functional groups on the adsorbent surface were further confirmed with Fourier Transform Infrared Spectroscopy (FTIR) analysis, whereas Field Emission Scanning Electron Microscopy (FESEM) images showed clear surface changes post-adsorption.
Quails require stable environmental temperature and humidity to maintain health, reduce thermal stress, and support productivity. Conventional threshold-based control systems often show limited adaptability to dynamic environmental fluctuations in small-scale poultry farming. This study proposes an adaptive temperature and humidity control system for quail cages based on a Fuzzy Logic Controller (FLC) implemented on an ESP32 microcontroller using real-time feedback from a DHT22 sensor. The proposed system employs the Mamdani fuzzy method to control the heater and blower actuators via pulse-width-modulated (PWM) signals. The novelty of this study lies in the development of a low-cost adaptive fuzzy control framework specifically designed for small-scale quail cage environments with simultaneous heater–blower regulation based on combined temperature and humidity conditions. Experimental simulation results demonstrate that at low-temperature and dry-humidity conditions (18°Celcius, 40 relative humidity), the system produces a heater PWM of 223.3 and a blower PWM of 29.7. Under ideal environmental conditions (27°C, 60%RH), both outputs decrease to approximately 26.7 PWM, indicating energy-efficient operation. At high-temperature and high-humidity conditions (35°C, 80% RH), the heater decreases to 27.3 PWM while the blower increases to 224.6 PWM. These findings confirm that the proposed system provides adaptive, stable, and responsive environmental control for quail cages.
Roadside type is a crucial factor that affects road safety. This study aims to investigate the impact of 15 roadside types using the international Road Assessment Program (iRAP) model, which utilises the star rating system as a measure of road safety. The study, uniquely, focuses on using risk assessment models to evaluate the impact of roadside types on road safety in the case of a lack of crash data. The required geometric and traffic data were collected for two sections of the Army Canal highway in Baghdad city. The results showed that one roadside type (wire rope) improved safety performance, while others led to a reduction or limited effect on safety levels compared to the existing metal barriers in each section. It was observed that this option lowers the Star Rating Score (SRS) for section 1, driver side and passenger side, from 12.71 to 11.58 and from 12.62 to 11.42, respectively, corresponding to an 8.9% and 9.5% reduction in risk score, which was sufficient to shift the road section from Star Rating 2 to Star Rating 3. The study revealed similar results for section 2 with a different SRS.
To increase the effectiveness of irrigation application, emission homogeneity, and economic return in the production process, drip irrigation system design is considered a crucial step. The goal of this study is to create a mathematical solution for the impartial function, which is a function of the subunit's total annual cost and combination of hydraulic emission uniformity, to obtain a relationship between the subunit's area and lateral and manifold lengths. The impartial function is expressed in terms of fundamental design parameters such as emitter and lateral spacing as well as manifold diameter. Mathematical techniques are then utilized to select the ideal number of laterals and manifolds for a given subunit. The results showed that the impartial function of the mathematical model increased by 6% to 64%, while the total annual cost decreased by 6% to 66% compared to the numerical model proposed in the previous study. The hydraulic emission uniformity values of the mathematical model were 89% to 97% for all cases used in this study. In general, the proposed model obtained a minimum total cost with reasonable hydraulic emission uniformity.
This work focuses on the preparation of a polymer matrix composite material, consisting of 90 vol% unsaturated polyester (UPs) and 10 vol% polyurethane (PU). The experiment was carried out in two stages. The first stage involved studying the effects of aluminium alloy (Al) mesh on the different ratios (5, 10, 15, and 20 vol%) of a polymer blend. The second stage entailed examining the additional effect of silica fume (SF) particles at different ratios (12 and 16 vol%). The results showed increases in (flexural strength, impact strength, hardness, and thermal conductivity), with higher metal mesh percentages, but when SF was added, thermal conductivity was lower compared to that of mesh, and hardness was higher than that of Al alloy mesh. The maximum values were as follows: B1 for flexural strength (180 MPa at 20 vol% Al alloy mesh, B1 for impact strength (9 kJ/m2) at 20 vol% Al alloy mesh, B3 for hardness (89 at 20 vol% Al alloy mesh and 16 vol%SF), and B1 for thermal conductivity (0.9 W/m x °C at 20 vol% Al alloy mesh).
Composite beams are widely used members in different applications and are subjected to various loads. Impact load is one of the dynamic loads generated by falling objects striking structural members, producing a short-duration load. This load affects the member’s structural performance, reducing it. In this study, a composite beam with a pultruded I-section was numerically investigated using finite element software. The model was validated by a previous experimental model conducted by a previous researcher. The model consists of a pultruded I-section and 20 MPa concrete slabs; the parameters studied here are three concrete compressive strengths: 50, 75, and 100 MPa. Alternative reinforcement types to steel bars, such as Glass Fiber Reinforced Polymer (GFRP) and Carbon Fiber Reinforced Polymer (CFRP) bars, were also studied. It was found that increasing concrete compressive strength decreases the impact effect on the composite beam. When Glass Fiber Reinforced Polymer bars were used, the stiffness of the impacted beam was reduced by 40% and ductility by 25%, making them the most vulnerable bars under impact.
Fixed photovoltaic panels suffer from a major issue, which is low energy production due to their inability to track the sun. To solve this problem, these panels are installed on systems equipped with appropriate actuators to ensure they remain permanently aligned with sunlight during the day, thereby increasing solar radiation absorption. This paper aims to design and implement double-acting pneumatic actuators to steer a sensorless dual-axis solar tracking system under the worst climatic conditions. To achieve accurate tracking movement, the tracking angles were modeled in this system. The pneumatic solar system is designed using MATLAB/SIMSCAPE. Several tests were conducted under the worst weather conditions in Baghdad to collect data on the system model's input and output signals and evaluate its real-time performance. By modeling the system, specific pneumatic components can be selected to achieve the desired behavior by predicting and optimizing the performance of the pneumatic actuators under load. The results demonstrated that the analytical and simulation models agreed. The findings showed that when the solar panel was angled in two axes rather than a fixed panel, its efficiency increased by 56.4%.
Groundwater in aquifers is a very important resource that can flow over long distances to meet the needs of areas that require it. However, its existence beneath the surface requires a good understanding of the water system to manage it properly. This study aimed to develop a system dynamics model to analyze the impact of water balance on the sustainability of groundwater resource development in Parepare, Indonesia. Meeting urban water needs through groundwater use is approximately 4,526,864 m³/year, significantly larger than surface water at 2,799,948 m³/year. System dynamics modeling was conducted using STELLA 10.0.4, with a 10-year simulation period. The research results show that this area experiences a rainy season for 9 months and a dry season for 3 months, but groundwater recharge occurs only for 6 months, with recharge potential ranging from 85,858 m3/month to 62,885,852 m3/month. Based on the results of the system dynamics modeling, the potential for groundwater recharge remains very high, supporting the development of new groundwater production wells to meet the water shortage, with a capacity of 239,208 m3/month.
