Search

Abstract Solar energy, a prominent renewable source, has reached an installed capacity of 71.78 GW in India. This research explored the load demands of the computer center at an engineering college in Tanjore, Tamil Nadu, India. The computer center at the engineering college has an annual energy requirement of 260,552 kWh/Year. Consequently, the research focused on the planning and implementation of a standalone photovoltaic (SAPV) system, assessing it against the institution's total annual energy consumption. The performance ratio and losses of the SAPV system with both direct coupling and an MPPT charge controller was compared. This comparative analysis aimed to evaluate the efficacy of two solar photovoltaic control methods—SAPV direct coupling and Maximum Power Point Tracking control—in optimizing energy harvesting from solar panels.

The present research computes the impact of process parameters of squeeze casting on AA8011/Si3N4/ZrO2 Hybrid Metal Matrix Composites (HMMCs). The melting temperatures (700 to 800°C), Si3N4 + ZrO2 (5 to 15 wt.%) and stirring speed (550 to 750 rpm) were selected as parameters for input. The AA8011 HMMCs were fabricated as per the combination of L9 input parameters, and they were subjected to Energy Dispersive X Ray Analysis (EDAX) and Scanning Electron Microscope (SEM) tests to compute the presence of wt.% of matrix and reinforcements and to confirm the uniform distribution of Si3N4 + ZrO2 in matrix AA8011. Besides, fabricated composites were subjected to tensile and micro hardness test after subjecting to Salt spray test (3.5% NaCl, 120 hours exposing duration and 1.2 kg/cm2 spray pressure) for computing the Ultimate Tensile Strength (UTS) and micro hardness. The Grey Relational Analysis (GRA) was employed for optimizing process parameters of squeeze casting on AA8011 based composites. The EDAX test results confirms that the increasing wt.% of silicon nitride and zirconium dioxide reinforcements enhances the presence of elements such as Si, N, Zr and O in manufactured composites. The higher dense reinforcements are uniformly distributed in the matrix AA8011 at the blend of input parameters of AA8011 composite. Based on the Taguchi approach, the medium level of melting temperature (750°C), higher level of wt.% of Si3N4 and ZrO2 reinforcements (15 wt.%) and higher level for speed of stirring (750 rpm) is the optimized combination parameters of squeeze casting for UTS and microhardness are identified. Based on the GRA technique, the influencing sequence are identified for squeeze casting process parameters are wt.% of Si3N4 + ZrO2 reinforcements, stirring speed and melting temperature for both UTS and Micro hardness. The contribution percentage of melting temperature, wt.% of reinforcements and stirring speed are 20.26%, 48.102% and 29.23% respectively. The confirmation test was done for optimized input parameters and it exhibit 56% higher UTS and 48.2% higher micro hardness of than AA8011 matrix material.

Abstract The reliable operation of power systems while integrating renewable energy systems depends on Optimal Power Flow (OPF). Power systems meet the operational demands by efficiently managing the OPF. Identifying the optimal solution for the OPF problem is essential to ensure voltage stability, and minimize power loss and fuel cost when the power system is integrated with renewable energy resources. The traditional procedure to find the optimal solution utilizes nature-inspired metaheuristic optimization algorithms which exhibit performance drop in terms of high convergence rate and local optimal solution while handling uncertainties and nonlinearities in Hybrid Renewable Energy Systems (HRES). Thus, a novel hybrid model is presented in this research work using Deep Reinforcement Learning (DRL) with Quantum Inspired Genetic Algorithm (DRL-QIGA). The DRL in the proposed model effectively combines the proximal policy network to optimize power generation in real-time. The ability to learn and adapt to the changes in a real-time environment makes DRL to be suitable for the proposed model. Meanwhile, the QIGA enhances the global search process through the quantum computing principle, and this improves the exploitation and exploration features while searching for optimal solutions for the OPF problem. The proposed model experimental evaluation utilizes a modified IEEE 30-bus system to validate the performance. Comparative analysis demonstrates the proposed model’s better performance in terms of reduced fuel cost of $620.45, minimized power loss of 1.85 MW, and voltage deviation of 0.065 compared with traditional optimization algorithms.

Abstract Repeated broiler litter application on agricultural lands can cause nutrient enrichment of subsurface effluent, especially with the existence of preferential flow through soil macropores. Previous studies quantifying soil macropores have not attempted to establish a connection of soil macropore characteristics with the subsurface nutrient (nitrogen [N] and phosphorus [P]) losses, across different topographical locations in the field. This study investigated the effect of broiler litter application and preferential flow on subsurface nutrient transport (N and P) at different topographical positions (upslope, midslope, and downslope) in a no‐till pasture field located in Alabama, USA. Twelve intact soil columns (150 mm id and 500 mm length) were used, and the nutrient leaching measurements from laboratory experiments were linked to soil macropore characteristics quantified using X‐ray computed tomography image analysis and solute transport modeling. Treatments included surface broadcast broiler litter (5 Mg ha−1, on dry basis) and unamended control. Leachates were analyzed for dissolved reactive P (DRP), total P (TP), and nitrate + nitrite‐N (NO3− + NO2−–N). The bromide breakthrough curves provided evidence of preferential flow in all columns. Litter application significantly increased leachate P concentrations, and average TP and DRP concentrations were significantly higher in the leachate from upslope columns compared to those at downslope location. The NO3−–N concentrations in leachate exceeded the US EPA drinking water standard of 10 mg L−1 in all the treatment columns. The highest flow‐weighted mean concentrations of TP and DRP, at 2.7 and 2.5 mg L−1, respectively, were recorded in the upslope columns. Soil physicochemical properties and nutrient leaching losses varied substantially across topographical positions, indicating a need for variable litter application rates to reduce P build‐up and subsequent leaching in vulnerable locations within the field. The relevance of the effect of topographic position on nutrient leaching found in this study should be further tested by investigating a wider range of slopes and soil types in pastures.

Ash gourd (Benincasa hispida) is a cucurbitaceous crop cultivated as an edible vegetable rich in vitamins, minerals, dietary fibers and antioxidants. In a field survey conducted in the Udumalpet region of Tamil Nadu during 2019, the incidence of mosaic disease on ash gourd crop was observed to be 75%. The DNA-A and DNA-B components of begomovirus genome have been identified as associated with this disease. Both the cloned DNA-A and DNA-B genomic components shared highest pairwise sequence identities with the isolates of tomato leaf curl New Delhi virus (ToLCNDV), a bipartite begomovirus. Recombinant analysis showed that both the components are possibly evolved through intra-species recombination between ToLCNDV isolates. Tomato leaf curl Bangladesh betasatellite (ToLCBB) is not naturally associated with this sample. The results of infectivity studies on ash gourd and other cucurbitaceous crops demonstrates the Koch’s postulates, when co-inoculation of DNA-A and DNA-B of ToLCNDV was undertaken. However, the inoculation of non-cognate ToLCBB along with DNA-A and DNA-B enhances the symptom expression and reduces the time taken for symptom development. Thus, Koch’s postulates were proved for these virus complexes on cucurbitaceous crops. Furthermore, an enhanced accumulation of DNA-A component was detected in the cucurbits co-inoculated with ToLCNDV and ToLCBB. This report highlights the importance of investigating the spread of these disease complexes with other cucurbitaceous crops in India.

The present study was conducted to determine the mutagenic effectiveness, efficiency and lethal dose of gamma rays in papaya varieties CO7, Arka Prabhath and Arka Surya. Papaya seeds were exposed to various doses of gamma rays (0Gy, 100Gy, 150Gy, 200Gy, 250Gy, 300Gy, 350Gy, 400Gy, 450Gy and 500Gy) and the mutagenic effectiveness and efficiency of gamma rays were assessed based on the chlorophyll mutation frequency and biological damage in M1 plant basis. There was a negative relationship between mutagenic effectiveness and efficiency with the doses of gamma irradiation. LD50 value was optimized in CO7, Arka Prabhath and Arka Surya as 354, 348 and 341Gy respectively. Generally, the germination, survival and growth rate of papaya decreased with an increase in gammairradiation doses. Lower doses of mutations created very few mutations and higher doses of gamma irradiation induced lethality and sterility of seedlings whereas, lethal dose 50 has proved to be more effective in inducing desirable mutations in papaya. Since identifying the mutagenic efficiency and effectiveness of the mutagen and optimization of lethal dose is the preliminary step in any mutagenic experiment, this study will offer a foundation for further gamma irradiation studies in papaya to develop desirable mutants.

In this study, the methanol extract of Musa acuminate leaves has a significant development on the quality of the protection features such as, antibacterial and ultraviolet protection, was observed. The fabric finished with a higher concentration of M. acuminata sap (7%) at the temperature rate of 40–50°C has higher zone of inhibition against gram-positive bacteria and improved ultraviolet protection factor than the controlled sample. The fabric finished with the lower concentration of M. acuminata sap (3% & 5%) has lesser zone of inhibition against gram-positive bacteria. The fabric finished with a 7% concentration of M. acuminata leaves methanol extract at 40–50°C shows high protection factor against antibacterial and ultraviolet protection. Hence, it is observed that the fabric finished with a higher concentration of M. acuminata sap exhibits a higher zone of inhibition against bacteria’s and ultraviolet protection factors when compared to the lower concentration of methanol extraction of M. acuminata leaves.

Background. This paper reports the baseline characteristics and outcomes of 266 Namibian patients in the Global Registry of Rheumatic Heart Disease. Objective. To describe clinical findings and outcomes in a cohort of children and adults with rheumatic heart disease in Namibia. Methods. Prospective study of all patients with rheumatic heart disease at Windhoek Central Hospital between January 2010 and November 2012. Results. A total of 266 patients were enrolled; median age was 22 years, 72.6% were

The unmanned aerial vehicles (UAV) have become a better solution for agricultural growers due to advanced features such as minimal maintenance costs, quick set-up time, low acquisition costs, and live data capturing. Near-ground remote sensing (drone) has opened up new agronomic opportunities for better crop management. This study predicted the seed cotton yield for a cotton field area located at Tamil Nadu Agricultural University, Coimbatore. Pearson correlation analysis and regression analysis were done for ground truth data and vegetation indices for validation and accuracy and also to find the best-performing indices. It was concluded that the Wide Dynamic Range Vegetation Index (WDRVI) showed a better correlation coefficient (R=0.959) with LAI ground truth data (R2=0.919). In contrast, the Modified Chlorophyll Absorption Ratio Index (MCARI) showed a better correlation coefficient (R=0.919) with SPAD chlorophyll ground truth data (R2=0.845). Then the best performing indices WDRVI and MCARI were further used for generating the yield model. High spatial resolution drone imageries for determining LAI and chlorophyll are reliable and rapid, as per the study. It helps to determine the LAI and chlorophyll at a spatial scale and their influence on yield production. This yield prediction was technical support for the widespread adoption and application of unmanned aerial vehicle (UAV) remote sensing in large-scale precision agriculture.

Aim. To assess the changes in cardiology diagnostics scope in the Russian Federation during the coronavirus disease 2019 (COVID-19) pandemic.Material and methods. In an online survey organized by the Division of Human Health of the International Atomic Energy Agency (IAEA), including questions about changes in the workflow of diagnostic laboratories and the scope of cardiac diagnostics from March 2019 (pre-pandemic) to April 2020 (first wave of the pandemic) and April 2021 (recovery stage), 15 Russian medical centers from 5 cities took part.Results. The decrease in the diagnostics scope by April 2020 by 59,3% compared to March 2019, by April 2021, stopped and was replaced by growth (+7,1%, the recovery rate, 112,1%). The greatest increase was in routine examinations, such as echocardiography (+11,6%), stress echocardiography (+18,7%), stress single photon emission computed tomography (+9,7%), and to a lesser extent resting computed tomography angiography (+7,0%) and magnetic resonance imaging (+6,6%). The performance of stress electrocardiography, stress magnetic resonance imaging and positron emission tomography for the diagnosis of endocarditis in April 2021 compared to March 2019 decreased by 10,3%, 63,2% and 62,5%, respectively.Conclusion. Due to the resumption of patient admissions for cardiac examinations during the ongoing COVID-19 pandemic, with the anti-epidemic measures taken and certain changes in the workflow, there has been a recovery in the diagnostics scope in most of the included centers.

Subpial haemorrhage is a rare cause of seizures in term neonates. A 3-day-old male infant, born at term with no history of perinatal hypoxia, presented with seizures and unremarkable physical examination in the interictal state. Imaging demonstrated left temporal subpial haemorrhage with the classic ‘yin-yang sign’ on MRI. The patient was subsequently diagnosed with factor XIII deficiency. Follow-up at 6 months and 12 months revealed encephalomalacia in the previous haemorrhagic areas with normal developmental milestones.

This study focused on investigating the influence of varying weight percentages of coconut shell charcoal (CSC) on the physical, mechanical, and wear properties of aluminum 7075 (Al-7075) matrix composites reinforced by boron carbide (B _4 C) and zirconium dioxide (ZrO _2 ). Throughout the study, these composites were prepared with a constant 3 wt% B _4 C/ZrO _2 . The developed composites were then subjected to the tribological analysis using a pin-on-disc apparatus under a constant sliding speed (2000 m), a sliding distance (4 m s ^−1 ), and varying operating temperatures (room temperature, 150, 200, and 250 °C). The worn-out surfaces of the composites were examined using a magnified scanning electron microscope (SEM) to investigate the microstructural analysis and wear behavior. The composites containing 3% B _4 C/ZrO _2 and 3% CSC exhibited the highest hardness and wear resistance among the studied composites. The incorporation of CSC increased the density and porosity of the composites up to a 3 wt%, but at 4 wt%, a decrease was observed. It is worth noting that the B-series samples had slightly lower hardness values compared to the Z-series samples. Regarding the effect of temperature, the wear rate decreased as the temperature increased. The Al-7075/ZrO _2 /CSC composite demonstrated improved wear resistance and coefficient of friction (COF) compared to the Al-7075/B _4 C/CSC composite, with respective enhancements of 19.30% and 42.19%. The analysis of variance (ANOVA) confirmed the significant impact of CSC weight fraction on wear for both composites, whereas only the Al-7075/ZrO _2 /CSC composites showed significance for COF. The SEM analysis revealed that the addition of CSC resulted in a uniform distribution of particles within the matrix, leading to improved wear resistance. Therefore, this study demonstrated that the addition of CSC influenced the density, porosity, hardness, wear resistance, and COF in the Al-7075 matrix composites. Optimal performance was achieved with a 3 wt% CSC for Al-7075/ZrO _2 /CSC at 250 °C. The composites developed in this study, comprising boron carbide (B _4 C)- and zirconium dioxide (ZrO _2 )-reinforced aluminum 7075 (Al-7075) matrix with varying weight percentages of CSC, have several potential applications such as in the fields of automotive, aerospace, defense, and industrial machinery.

This paper focuses on the thermal properties of R-Glass/Epoxy laminate in response to temperature variations. The elastic properties and coefficient of thermal expansion in the material's principal direction were measured across the temperature range from room temperature to the cure temperature. These properties were then characterized as functions of temperature. Using the characterized properties and the principles of classical lamination theory, a method was proposed to predict the changes in the coefficient of thermal expansion for a general laminate subjected to temperature variations. The measured values of the coefficient of thermal expansion for laminates with varying angle plies were compared with the predicted values. The experimental results demonstrate that the proposed method accurately predicts the changes in the coefficient of thermal expansion for a general laminate under temperature variations. Additionally, an analytical formulation was proposed and validated to predict the changes in the coefficient of thermal expansion for R-Glass/Epoxy laminates subjected to temperature variations. [ABSTRACT FROM AUTHOR]