446494 research outputs found
Sort by
Integrated Decision-Support Perspectives for Soil, Water, and Plant Health Management in Semi-Arid Agriculture
No full textIn semi-arid areas of the world agriculture is often challenged by numerous interconnected issues that are related to water availability, soil deterioration, climate fluctuations and increased susceptibility of crops to environmental and biological stress factors. As many of these factors seldom exist alone, the relationships between irrigation practices, the status of the soil and the health of plants develop and evolve over time through multiple interactions at different spatial and temporal levels. Yet, many current decision support tools are limited to single agronomic criteria; therefore, they do not adequately address the complexities of managing agricultural production under realistic field conditions. In response to the need for integrated crop management, this research addresses the dynamic interdependencies of soil, water and plant health in semi-arid agricultural systems. Therefore, the emphasis of this proposed methodology will be on coordinated interpretation versus separate prediction capabilities which will result in decision making that is both consistent with agronomic best practices and more reliable. Through analysis of soil moisture variability, irrigation sensitivities and disease pressures from an integrated point of view, the objectives of this research are to demonstrate that multidimensional decision-making processes may lead to improved crop resilience and decreased risk associated with management decisions. Ultimately, the objective of this research is to emphasize the need for comprehensive decision support tools that support sustainable and adaptable agricultural production in data-limited, semi-arid environments
Performance Enhancement of Solar Air Heaters Using Triangular Channels
No full textThis paper provides a comparative numerical analysis of two solar air heater (SAH) designs: an improved design with internal triangular air flow channels (SAH 2) and a standard flat-plate duct design (SAH 1). The thermal performance of the two systems under varying levels of solar radiation, typical of a typical day, was investigated using computational fluid dynamics (CFD) from COMSOL Multiphysics. Transient behaviour of heat transfer and airflow was modelled using a time-dependent solver over a period of 08:00-18:00, when solar irradiance varied on an hour-by-hour basis between 180W/m2 to 1000W/m2. It was obtained that the overall thermal performance of SAH 2 under all measured parameters has greatly increased when using triangular channels. The outlet temperature and useful heat gain in SAH 2 have been seen to be higher than in SAH 1 and thus peak colony temperatures in excess of 330K and improvement of the thermal efficiency of up to 20.5 can be observed as well. There were increased convective heat transfer coefficients and inter mixing of air flow because of the changes in geometry leading to increased efficiency in the use of solar energy. Although an increase of the pressure drop occurs at moderate levels, these benefits on performance can justify the application of SAH 2 as a potential passive solar heating solution. This paper demonstrates that triangular channel enhancement to the geometry is a valid way of enhancing the effectiveness of solar thermal systems
A Review on Performance Evaluation of Solar Photovoltaic-Thermal (SPT) Technology
No full textThe continuous decline in environmental quality and the ever-increasing global energy demand, coupled with the rising cost of traditional energy sources, have prompted scientists to seek more stable, long-term, and sustainable energy alternatives. To address these issues, renewable sources must play a major role. Among these, solar power generation systems fulfil technical, environmental, and cost requirements, making them the best alternative. While a major limitation in electrical systems is the lack of large-scale power storage (only a few MW), the hybrid Solar Photovoltaic-Thermal (SPT) system has become a trending technology. This system uses PV technology to meet the electrical load, while the remaining solar radiation (excess heat) is stored in the form of heat when the available solar radiation is greater than the load demand. This stored energy can be converted into useful thermal or electrical forms, maintaining continuity of supply and maximizing the utilization of solar radiation. Significant innovative developments have been undertaken to enhance the performance of solar thermal systems. This paper provides a comprehensive review of methods for enhancing PVT technology, classifying PVT systems and discussing the various factors that influence and improve SPT system performance
Measurement and evaluation of Scattering parameters for Surface wave communication-based waveguide at millimetre range frequency band
No full textThe surface wave communication-based waveguide (SWW) can replace copper traces to cater millimeter wave frequency bands with loss losses [1], the efficiency of the proposed waveguide has been analyzed considering various factors like surface impedance, dispersion, power flow and attenuation. We have been focused on scattering parameters and Voltage standing wave ratio (VSWR) in this article which are also the fundamental factors to analyze the signal loss, at the frequency range 50 GHz to 150 GHz, we have compared the theoretical entities of these parameters with the simulated results. The entire analysis and comparison prove that the optimum scattering parameters and VSWR were achieved with the proposed SWW as per the expectations than existing copper traces, we have considered copper as the conductor, Teflon as the dielectric material keeping the thickness of the conductor and dielectric at 0.2mm, the entire simulation performed using CST Studio suite
Performance Evaluation of Handcrafted Feature Descriptors with AdaBoost Classifier for Automated Skin Disease Diagnosis
No full textThe timely identification of dermatological diseases together with their precise diagnosis enables proper medical interventions that minimize further disease complications. The authors conduct a performance- based evaluation of AdaBoost classifier with handcrafted image features for automated skin disease classification systems. The researchers worked with a specific collection of 38,000 dermatological pictures which included ten different disease types from Melanoma to Eczema to Psoriasis to Fungal Infections. The research investigated six image feature extraction methods including Gabor Filter and JPEG Coefficient Filter (JPEGCF) and Pyramid Histogram of Oriented Gradients Filter (PHOGF) as well as Simple Color Histogram Filter (SCHF) and Fuzzy Color and Texture Histogram Filter (FCTH) with Fuzzy Opponent Histogram Filter (FOHF). The research used feature vectors extracted from AdaBoost classifiers in WEKA within 10-fold cross-validation procedures for training purposes. The evaluation metrics consisted of accuracy, precision, recall, ROC, PRC as well as training time. Within the examined models Gabor+AdaBoost demonstrated maximum rates of accuracy (97.78%) alongside precision (0.98) and recall (0.98) but it required the most execution time at 14.4s. When weighed against each other JPEGCF+AdaBoost maintained equivalent accuracy at 97.59% but required only 0.21 seconds to complete tasks thus earning status as a balanced choice for this system. SCHF+AdaBoost proved suitable for real-time operations by delivering 94.11% accuracy results within 0.06 seconds computing time. The study reveals that Gabor descriptors provide optimal predictive accuracy but JPEGCF along with SCHF demonstrate the best combination of performance with computational speed
Collision Alert System: Computer Vision for Vehicle Safety
No full textThis paper introduces an innovative, vision-based Collision Alert System (CAS) aimed at significantly enhancing vehicle safety in complex driving environments. Our approach advances beyond existing YOLO-based Advanced Driver- Assistance Systems (ADAS) through its unique integration of YOLOv8’s real-time object detection with specialized Dynamic Region of Interest (ROI) processing and Angular Methods for precise trajectory analysis. This framework, combined with robust object tracking, enables proactive collision prediction. We detail the system’s architecture and operational flow, emphasizing its real-time performance. Rigorous evaluation confirms a True Positive Rate exceeding 95% and a remarkably low False Positive Rate under 2%, while maintaining over 30 Frames Per Second (FPS) for timely driver alerts. The paper also discusses core algorithmic principles and effective strategies for addressing real- world challenges like variable illumination and camera instability. A video demonstrating the system’s live operation is available online. Future work focuses on multi-camera data fusion and integration with active vehicle control
Intelligent IoT-based Runway incursion detection for Aircraft system
No full textRunway incursions pose a serious threat to the safety of aviation and, as such, necessitate proactive and intelligent mitigation measures. Traditional surveillance systems are usually inefficient and far from automated when it comes to real-time risk assessment. Recent developments in AI, IoT, and computer vision have made it possible to create cutting-edge systems for prevention systems. The cloud-enabled monitoring interface uses simple communication with air traffic control for timely action. By utilizing deep learning-based object detection, along with edge computing, the system offers fast and efficient detection of a potential threat. The proposed solution, is designed to work in changing environmental conditions and is highly reliable and scalable. Computer vision enhances situational awareness and reduces human dependency. Tests showthat the system can detect, classify, and sort obstacles with a high level of accuracy. This approach allows for improved operational dependability and will be kept current with contemporary aviation safety regulations. We expect a lot of coverage and accuracy from the detecting algorithms through possible enhancements. The following study emphasizes how AI-based automation can be used to improve airport security protocols
Study on the Reliability of Electric Motor Boat Propeller Structure Due to Axial Load
No full textThis study investigates the structural reliability of B-Series propellers used in electric motor-driven ships under axial loads induced by fluid flow. The distinct operating characteristics of electric propulsion systems require dedicated reliability assessment to ensure safe and efficient performance. Computational Fluid Dynamics (CFD) simulations were conducted under uniform viscous flow conditions to evaluate hydrodynamic loading, yielding a maximum axial load of 32.74 kN at a rotational speed of 1500 RPM. The resulting loads were applied in Finite Element Method (FEM) simulations to assess structural stress and deformation, with maximum values of 273.27 MPa and 5.10 mm, respectively. Structural reliability analysis was performed using probability density functions of hydrodynamic loads and aluminum alloy material strength. The results indicate a structural reliability of 99.90% at a ship speed of 10 knots, which decreases significantly to 33.31% at 20 knots. The inclusion of safety factors of 10% and 40% effectively increased reliability by 9.99% and 100%, respectively. These findings emphasize the importance of appropriate safety factors and material selection to improve the structural reliability of electric motor ship propellers under high-speed operating conditions
Distribution of Cromium (Cr) in the Bottom Substrate around Kebintik and Batu Belubang Coastal Waters, Bangka Island
No full textWithin the next five years, the post-tin mining coastal waters of Kebintik and Batu Belubang in Central Bangka are expected to run out. Habitats for commercially significant and community-consumed benthos (bivalve class, such as Anadara granosa and Meretrix meretrix) can be found in both coastal seas. Consequently, there are worries regarding the effects of heavy metals (such Cr) from tin mining on marine resources since they build up in the biota, which is eventually ingested by humans. This work uses quantitative descriptive methods and Cr measurement with ICP-EOS to evaluate the concentration and distribution of Cr in sediments surrounding Kebintik and Batu Belubang coastal waters. According to the findings, the sediments in both coastal waterways had Cr concentrations ranging from 0.0210 to 0.044 ppm (the category is still within the quality threshold). The area of post-tin mining tailings pilings at station 6 had the largest dispersion of Cr. The distribution and concentration of heavy metals in the sediments of Kebintik and Batu Belubang's coastal waters are still below the quality standards, meaning that the waters are still suitable for benthic life—which is significant to the local economy and does not pose a health risk to humans—and are therefore generally in good condition