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The present numerical study employs a passive flow control augmentation mechanism to enhance the hydrodynamic performance of the Savonius hydrokinetic turbine. Two cylindrical deflectors guide the flow over the Savonius rotor blades. The effectiveness of placing the deflectors is examined by positioning them upstream of the returning and advancing blades. The Savonius hydrokinetic rotor’s efficiency is improved by incorporating Deflector1 to decrease the counteracting torque from the returning blade and Deflector2 to magnify the positive torque produced by the advancing blade. The study focuses on finding a suitable position (L1) and size (d1) of Deflector1 while keeping the size (d2) and position (L2 and α) of Deflector2 fixed. The diameter of Deflector1 (d1) changes as d1=d =0 .15, 0.20, 0.25, 0.30, and 0.35 for each position, L1=d of 1.35, 1.65, 1.95, and 2.25. The study reports that the augmented Savonius turbine operates most efficiently at d1=d =0 .15, L1=d = 1.65, corresponding to a tip speed ratio of 0.9. The deflector-assisted Savonius hydrokinetic turbine enhances the power coefficient (CP) by 54.1% in comparison to the ordinary Savonius rotor lacking deflectors. Further, utilizing cylindrical deflectors upstream of the Savonius hydrokinetic rotor improves the operating TSR range of the Savonius hydrokinetic turbine. [ABSTRACT FROM AUTHOR]

The study on changes in physico-chemical parameters of fruit on eight ber cultivars viz. Chhuhara, Chinese, Kalagola, Nazuk, Sanaur-2, Sanaur-4, Umran and ZG-2 was conducted at Horticulture Research Centre, Patharchatta, G. B. Pant University of Agriculture & Technology, Pantnagar, U.S. Nagar, Uttarakhand, India during the season of 2017–18 and 2018–19. The experiment was laid out in two factors Randomized Block Design (RBD) with three replications. Sampling dates and cultivars were considered as the treatments. There were 11 sampling dates ranging from 28 to 168 days after full bloom (DAFB), with observations taken at biweekly interval. In pooled data at 168 DAFB, Sanaur-2 recorded the maximum (6.89) pH while the minimum (6.62) in Kalagola. Umran recorded the maximum (83.55) ascorbic acid while the minimum ascorbic acid content was found in Sanaur-4 (66.50). Chhuhara recorded the maximum (9.31) total sugars while the minimum (7.55) in Umran. Chhuhara recorded the maximum (4.45) reducing sugars while the minimum (3.19) in Kalagola. Chinese recorded the maximum (5.08) non-reducing sugars while the minimum (4.06) in Umran. Chhuhara recorded the maximum (138.38) TSS: acid ratio (Total soluble solids: acid ratio) and minimum (75.78) in Kalagola. The findings therefore imply that matured ber could be used for naturally occurring antioxidants and that the advanced ripening stage is the best time to collect fruit for fresh consumption or for commercial processing. Breeders will be helped by these kinds of studies to create new breeding programmes, find potential cultivars for breeding, and choose the best time to harvest for domestic and international markets. [ABSTRACT FROM AUTHOR]

Ziziphus mauritiana is a drought and salinity-tolerant crop and one of India's most crucial arid fruit trees. The present study evaluated the fruit development of ber based on durational advancement in eight different cultivars, viz. Chhuhara, Chinese, Kalagola, Nazuk, Sanaur-2, Sanaur-4, Umran, and ZG-2. The developmental stages were chosen based on the number of days after full bloom: these stages included 28, 42, 56, 70, 84, 98, 112, 126, 140, 154, and 168 days after full bloom. With the advancement in fruit development, fruit firmness continued to decline till 168 days after full bloom. Total carotenoid content and flavonoid content were observed to increase as maturity progressed, but phenolic content decreased. The total antioxidant activity was also found to increase over time. Significant varietal differences were observed in the developmental changes in the quality attributes. To find optimized maturity time, varieties were grouped into four similar clusters. A normalized average maturity index was developed for each cluster. Depending upon the developed maturity index, a harvesting duration of 154 days after full bloom was found suitable for all tested varieties except ZG-2, for which 140 days after full bloom was found ideal as time for commercial harvest. The current experiment simplifies the complex maturity indices to a single harvesting time for each varietal cluster to act as ready recommendations to fruit growers. [ABSTRACT FROM AUTHOR]

The problem of simultaneous tuning of the automatic generation control (AGC) regulator’s gains of multi-area interconnected power system is carried out in this manuscript. Based on the types of area interconnections, a power system model consisting of reheat turbines is investigated by two test cases for the AGC study. In one of the test case AC link is used as area interconnection, whereas the parallel combination of AC/DC links is used as area interconnection in other test case. Each test case control area is consisting of plants with reheat thermal turbines. Genetic algorithm (GA) is used to globally optimize the gains of proportional integral-based AGC regulators with simultaneous optimization of frequency bias coefficient and tie-line power flows. The dynamic response curves are obtained for various system states with the implementation of designed GA-based AGC regulators considering 1% load perturbation in one of the areas. The conventional AGC regulators are also developed using the popularly known Ziegler–Nichols technique. The investigations carried out demonstrate the superiority of proposed regulators over the conventional AGC regulators. The incorporation of DC link in parallel with AC link as an area interconnection has also exhibited favorable effect on dynamic response of the system. [ABSTRACT FROM PUBLISHER]

A new intelligent Automatic Generation Control (AGC) scheme based on Evolutionary Algorithms (EAs) and Fuzzy Logic concept is developed for a multi-area power system. EAs i.e. Genetic Algorithm–Simulated Annealing (GA–SA) are used to optimize the gains of Fuzzy Logic Algorithm (FLA)-based AGC regulators for interconnected power systems. The multi-area power system model has three different types of plants i.e. reheat, non-reheat and hydro and are interconnected via Extra High Voltage Alternate Current transmission links. The dynamic model of the system is developed considering one of the most important Governor Dead Band (GDB) non-linearity. The designed AGC regulators are implemented in the wake of 1% load perturbation in one of the control areas and the dynamic response plots are obtained for various system states. The investigations carried out in the study reveal that the system dynamic performance with hybrid GA–SA-tuned Fuzzy technique (GASATF)-based AGC controller is appreciably superior as compared to that of integral and FLA-based AGC controllers. It is also observed that the incorporation of GDB non-linearity in the system dynamic model has resulted in degraded system dynamic performance. [ABSTRACT FROM PUBLISHER]