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In response to challenges such as the subtle early fault indications and the fluctuating harmonic content in power systems affecting diagnostic accuracy， this paper presents a novel method for analyzing and diagnosing inter-turn short circuit faults in dry-type air-core reactors， taking into consideration the influence of harmonic voltages. Addressing three distinct operating conditions such as normal reactor operation， early-stage arc-type inter-turn short circuits， and mid-to-late-stage metal fusion-type inter-turn short circuits， the paper analyzes the operational characteristics of both series and parallel reactors under fault conditions to identify specific early fault indicators for inter-turn short circuits in each configuration. Additionally， the paper establishes a simulation model for inter-turn short circuit faults in reactors that accounts for harmonic voltage effects and analyzes the variation in electrical characteristics of series and parallel reactors under various operating conditions. Subsequently， it proposes a diagnostic method based on the current harmonic ratio for series reactor faults and another method based on the active power ratio for parallel reactor faults. To validate the effectiveness of the proposed method， the paper constructs an experimental test platform for inter-turn faults in series and parallel reactors and conducts experiments to confirm its correctness and efficacy.

Due to the influence of local complex topography and local severe convective weather system, wind events measured in mountainous valleys exhibit significant variability, that is, wind speed and wind direction often change rapidly in a short duration, which can pose a serious risk to the safety of many wind-sensitive infrastructures. However, the characteristics of steady winds in the atmospheric boundary layer have attracted extensive attention, but research on wind events with significant variability in mountainous valleys is still very insufficient. Therefore, based on the long-term wind field data collected by ultrasonic anemometer in a typical mountain valley of the Tibetan Plateau, the wind characteristics of these special wind events are comprehensively investigated. First of all, an effective quantifying approach is established to evaluate the variability levels based on the proposed spread metrics in statistics, which enables the identification of wind events with significant variability from the measured datasets. Furthermore, with the aim of obtaining turbulence components in three directions, and time-varying means to describe the trends of wind speed, wind direction, and angle of attack, an analysis strategy based on the moving average is presented. Finally, the mean characteristics and turbulence characteristics are investigated and compared with the steady wind events. The outcome of this study is expected to enhance the understanding of these special wind events and provide valuable reference for wind–structure interaction analysis in mountainous valleys. [ABSTRACT FROM AUTHOR]

We estimated the efficiencies of the eight cotton-growing provinces (autonomous region) by using data envelopment model (DEA) and employing the data from 1978-2007. And we calculated the subsidy quota on cotton under the conditions of efficiency-priority, fairness priority and giving attention to both in 2007 by using multiple objective optimization method. Moreover, we promoted the model on the considerations of non-reliance on imports, national grain stable safe supply, reasonable income for farmers and subsidy balance among provinces (autonomous region) by improved greedy method. We therefore come to the conclusion that our national actual distribution of cotton-growing subsidy is slanted toward fairness while lacking efficiency. The policy need to intensify the subsidy on main cotton-growing area as Xinjiang and the subsidy on Yangtze River basin cotton-growing area, thereby significantly extending the acreage of cotton-growing area. [ABSTRACT FROM AUTHOR]