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A self-adaptive energy storage coordination control strategy based on virtual synchronous machine technology was studied and designed to address the oscillation problem caused by new energy units. By simulating the characteristics of synchronous generators, the inertia level of the new energy power system was enhanced, and frequency stability optimization was achieved. This strategy is integrated with the frequency response model of the new energy power system to improve the system's frequency regulation capability and achieve more stable and efficient operation. From the results, the damping of the system increased, the oscillation frequency decreased after a duration of about 15 s, and the system stability improved by 76.09%. The proposed strategy based on virtual synchronous generator adaptive energy storage coordination control strategy was improved by 83.25%. In addition, the proposed strategy has improved stability indicators and system completion efficiency by 40.57% and 22.21% respectively, both of which are better than the comparative strategies. As a result, this strategy significantly enhances the frequency regulation capability of the system, which has a positive effect on achieving efficient operation of the new energy power system and maintaining the stability of the power system. [ABSTRACT FROM AUTHOR]

Global warming has caused poleward mangrove expansion, but extreme climatic events have significantly impacted the mangroves along their boreal limits. This study aimed to determine which natural hazard is more important in limiting the sustainability and survival of subtropical black mangroves—hurricanes or freezing events? Satellite and drone images indicated Hurricanes Zeta and Ida (2020–2021) caused only minor impacts on mangrove area (~ 5%, 6.32 ha) compared with the extensive mangrove degradation (defoliation and dry branches) caused by the winter freeze of Dec/2017–Jan/2018 (~ 89%, 110 ha) at Port Fourchon, LA. However, mangroves impacted by that winter freeze had a faster recovery (~ 1 year), while the losses of mangrove areas caused by those hurricanes were longer-lasting. This finding is novel and important because it implies that subtropical mangroves have low resistance but high resilience to winter freezes, while these forests present high resistance but low resilience to hurricanes. Overwash processes driven by hurricanes are the primary threat to mangroves at Port Fourchon due to the high rate of beach barrier retreat, which causes the burial of the back-barrier wetlands. Beach renourishment projects are essential to guarantee the stability of the beach barrier and slow down the increased losses of mangrove and salt marsh areas caused by hurricanes and relative sea level rise. [ABSTRACT FROM AUTHOR]

Crumb rubber concrete (CRC) is a cementitious composite produced by incorporating rubber crumbs into normal concrete (NC), characterized by large deformation, high damping, high energy absorption, and lower Young's modulus than normal concrete. This article presents a study on the seismic performance of frame structures under four scenarios: one normal concrete frame and three CRC frames. The total lateral stiffness, fundamental period, lateral earthquake loading, and interstory lateral displacements are calculated and compared based on the standardized design procedure. The results indicate that CRC frame structures increase the fundamental period and reduce the lateral earthquake loadings. The fundamental period of the CRC columns and beams (S3) is increased by 5.48% against normal concrete beams and columns (S0). However, decrease in the total lateral stiffness and increase the interstory lateral displacements was observed. The lateral earthquake loading is reduced by more than 4% against S0. These two competing factors determine the plausibility and benefit of CRC in structural application regarding earthquake design. The inter-story lateral displacements of CRC structures are still within the permissible design limits, confirming CRC's plausibility in structural application. This study also lays the technical ground for further exploring CRC in concrete structural applications that may recycle large quantities of scrap automobile tires. [ABSTRACT FROM AUTHOR]

Stripe rust is a devastating disease of wheat worldwide. Chinese wheat cultivar Lanhangxuan 121 (LHX121), selected from an advanced line L92-47 population that had been subjected to space mutation breeding displayed a consistently higher level of resistance to stipe rust than its parent in multiple field environments. The aim of this research was to establish the number and types of resistance genes in parental lines L92-47 and LHX121 using separate segregating populations. The first population developed from a cross between LHX121 and susceptible cultivar Xinong 822 comprised 278 F2:3 lines. The second validation population comprised 301 F2:3 lines from a cross between L92-47 and susceptible cultivar Xinong 979. Lines of two population were evaluated for stripe rust response at three sites during the 2018–2020 cropping season. Affymetrix 660 K SNP arrays were used to genotype the lines and parents. Inclusive composite interval mapping detected QTL QYrLHX.nwafu-2BS, QYrLHX.nwafu-3BS, and QYrLHX.nwafu-5BS for resistance in all three environments. Based on previous studies and pedigree information, QYrLHX.nwafu-2BS and QYrLHX.nwafu-3BS were likely to be Yr27 and Yr30 that are present in the L92-47 parent. QYrLHX.nwafu-5BS (YrL121) detected only in LHX121 was mapped to a 7.60 cM interval and explained 10.67–22.57% of the phenotypic variation. Compared to stripe rust resistance genes previously mapped to chromosome 5B, YrL121 might be a new adult plant resistance QTL. Furthermore, there were a number of variations signals using 35 K SNP array and differentially expressed genes using RNA-seq between L92-47 and LHX121 in the YrL121 region, indicating that they probably impair the presence and/or function of YrL121. [ABSTRACT FROM AUTHOR]