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This paper presents a new approach for circular array of parasitic dipoles composed by one active dipole for reduction of side lobe level with maximum directivity including mutual coupling. The desired goal is obtained by changing the spacing between the parasitic elements and length of the parasitic elements while the position and length of driven element is fixed. In addition to it, reflection coefficient (RC) of the driven element is kept closer to the specified value. Matlab based method of moment code is used to evaluate the performance of circular antenna designs generated by QPSO algorithm. Two examples are presented to show the effectiveness of this proposed approach.

Background: The primary public health issue, especially in low- and middle-income countries, is early pregnancy loss driven by miscarriage. Understanding early pregnancy losses and the characteristics of mothers who have miscarriages is essential to creating effective reproductive health strategies. Thus, this study's primary goal is to delve into the factors which impact miscarriages that take place prior to and following the first 12 weeks of gestation., Methods: The bivariate analysis was employed to determine the frequency of miscarriages. The factors associated with miscarriages in the first (≤12 weeks) and second & above (> 12 weeks) trimesters of pregnancy were then examined using a generalised linear regression model, with 95% confidence intervals. Finally, we use ArcGIS to illustrate the prevalence of miscarriage in the districts of India., Results: Our result shows that miscarriages occur often in India (4.9%), with 23% of cases occurring in the first trimester (≤12 weeks). In our bivariate analysis, we identified several factors associated with a higher prevalence of miscarriages in India. It was found that mothers aged thirty years or older, residing in urban areas, with less than ten years of education, belonging to the richest wealth quantile, expressing a desire for more children, having no demand for contraception, and possessing no parity experienced a higher prevalence of miscarriage in total pregnancies in India. On the other hand, the generalised linear model's findings show that mothers who are thirty years of age or older, practise other religions, live in urban areas, are members of other castes, want more children, marry before the age of eighteen, and meet their contraceptive needs are more likely to have miscarriages in total pregnancy. However, there is a larger likelihood of miscarriage in the first trimester (≤12 weeks) for mothers who follow other religions, live in urban areas, are from Other Backward Class (OBC), get married before the age of eighteen, and fall into the middle and upper wealth quantiles. A mother is more likely to miscarriage in the second & above (> 12 weeks) trimesters if she is older than thirty, from other castes, wants more children, has moderate media exposure, marries before turning eighteen, meets her contraceptive needs, and does not feel the need for contraception. After accounting for socioeconomic characteristics, all results were statistically significant., Conclusions: Given the substantial number of miscarriages in India, police need to improve planning and guidance in order to lower pregnancy loss due to miscarriage. Miscarriage rates may be significantly decreased by enhancing the availability and quality of reproductive health care infrastructure, particularly in rural areas., (© 2024. The Author(s).)

This study uses novel evolutionary algorithms and computational techniques to analyze wind potential on flat, complex coastal, and offshore sites utilizing mast as well as remote sensing data. The wind data were recorded using remote sensing technique and conventional technique. The optimum Weibull parameters are estimated using nine methods. The genetic algorithm, particle swarm optimization, and TLBO algorithms are compared and evaluated. The goodness of fit test, such as root mean square error test (RMSE), mean absolute percentage error (MAPE), coefficient of determination (R 2 ), and chi-square test (X 2 ), is used to evaluate the accuracy of the selected methods. Parameter estimates are used to compute wind densities. The TLBO and PSO algorithms outperformed genetic algorithms in terms of efficiency. This research compares remote sensing measurements to cup anemometer measurements., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The accurate selection of the wind speed distributions is crucial for a better utilisation of wind energy. The Weibull distribution is most commonly used distribution and hence its parameters need to be optimized. In this study five numerical methods, namely, maximum likelihood method (MLM), graphical method (GM), empirical method of Justus (EMJ), modified maximum likelihood method (MMLM) and wind atlas analysis and application program (WAsP) and three metaheuristic optimization algorithms, namely, social spider optimization (SSO), particle swarm optimization (PSO) and genetic algorithm (GA) are applied for estimating Weibull distribution parameters at three different locations (onshore-Kayathar, nearshore-Jafrabad and offshore-Gulf of Khambhat (GOK) in India and also comparison of numerical and optimization methods are employed to tune the optimal parameters. The accuracy of the methods was evaluated using three different statistical analysis techniques. As per the results, GOK has the maximum wind power density of 450.2 W/m 2 compared to Jafrabad and Kayathar. It was observed that among the five methods used for Weibull parameters estimation, WAsP method presented a better curve fit with the histogram of the wind speed. The results shows that SSO and PSO presents a comparably better performance than GA in the term of accuracy on the basis of closeness to converged solution., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

One approach for reducing the level of environmental contamination threats around the world is to use renewable energy-harvesting equipment. Wind is a potential environmental resource that has become a desirable aspect of urban use due to advances in wind turbine design technology. Other variants have been developed based on the classic vertical-axis Savonius rotor model, which, according to experimental test findings and computational calculations, show higher operational characteristics performance. Generated power and shaft torque operational results are obtained by providing specific rotor blade shapes in these models, one of the most common designs, among small-scale rotor which uses a drag-based vertical axis whereas Savonius turbines having large-scale rotors not developed yet. This kind of rotor has the advantages of being simple to design, affordable, performing well at low speeds, and turns to flow direction independently. However, it was discovered that the Savonius rotor suffers through high quantity of negative torques created by the returning blade after a number of examinations into its performance. Many studies on various rotor types have been conducted to resolve the Savonius turbine's performance constraints. The research showed and analyzed the difficulties and modification in design parameters of rotor, as well as their major impact on rotor performance., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Wind energy is the second largest source of renewable energy, across the world. For designing and construction of wind farms, most critical information is consistent wind resource assessment forecasts and appropriate models of wind speed distribution for a particular site. The purpose of this study is to provide the wind characteristics and wind potential evaluation of offshore locations, in Gujarat in India, using the wind Weibull density function. The Weibull shape k and scale c parameters are computed using six distinct numerical approaches at two different heights, to determine wind power density. The LiDAR sensor was used to capture the time series wind data. The goodness of fit test, which includes the RMSE, R 2 , MAPE, and χ 2 is considered to evaluate the performance of the selected methods. Wind power densities are calculated from the acquired results with the help of estimated parameter values, all the methods used in this study were found to be appropriate for Weibull distribution parameters estimation. The MLM has been determined to offer the most accurate evaluation of wind potential. The WPD computed from observed wind data was compared to the obtained power densities of the specified region. The evaluated data is a considered as preliminary characteristic of wind potential that aids in the wind energy conversion and determining the actual wind potential of a specific site., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)