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• The equivalent circuit of a UHV transmission system with Hybrid Reactive Power Compensation (HRPC) is developed. The waveforms of the interrupting current and transient recovery voltage (TRV) of a CB are simulated before and after installation of HRPC. • The interrupting severity is proposed to evaluate the interrupting characteristics. • Several factors of the circuit breakers, including the peak value of the TRV, the rise rate of the transient recovery voltage, and the interrupting current, will change the interrupting characteristics of phase-to-phase fault under various operating conditions. This paper presents a theoretical study of the interrupting characteristics of circuit breakers in the event of phase-to-phase faults in UHV transmission lines with hybrid reactive power compensation (HRPC). The study uses the transmission line parameters of the Jindongnan–Nanyang–Jingmen UHV AC pilot demonstration project in China and establishes a simplified model for the distribution parameters of transmission lines. Mathematical expressions describing the relationships between circuit breaker interrupting parameters and compensation degrees of HRPC are derived. Based on these mathematical expressions and their comparisons with simulation results, the effects of HRPC on circuit breaker interrupting characteristics and on the parameters of the phase-to-phase fault circuit are determined, in which case the validity of the analytical method is verified. The results of this study will provide a theoretical foundation for practical implementation of HRPC in UHV transmission. [ABSTRACT FROM AUTHOR]

Transient ischemic attack (TIA) is often recurrent, and about one-third of patients will progress to cerebral infarction. Rapidly identifying high-risk patients is pivotal to prevent the development of cerebral infarction. Therefore, this study aimed to evaluate the value of ABCD score, ABCD score combined with magnetic resonance diffusion weighted imaging (DWI) and intracranial arterial magnetic resonance angiography (MRA) in predicting cerebral infarction after 2 to 30 days of transient ischemic attack (TIA).182 patients with TIA from August 2011 to August 2014 were enrolled as study subjects, and their clinical data, test results of DWI and MRA were collected. The incidence of cerebral infarction was observed at 2 days, 7 days and 30 days after TIA in patients with TIA, through scoring according to the 7-point ABCD score method proposed by Johnston. The relationship between ABCD score, performances of DWI and MRA and the early incidence of cerebral infarction after TIA was analyzed. The accuracy rating of ABCD score and ABCD + DWI + MRA score used for predicting the early incidence of cerebral infarction after TIA were compared with each other.The incidence of cerebral infarction after TIA was 19 cases (10.4%) in 2 days, 42 cases (23.1%) in 7 days, 56 cases (30.8%) in 30 days respectively. For the ABCD score of incidence of cerebral infarction 2 to 30 days after TIA, that of those with high risk was higher than that with medium risk, and that with the medium risk was higher than that with low risk (P < .05). The area under the curve of ABCD + DWI + MRA score and ABCD score predicting the incidence of cerebral infarction was: in 2 days: 0.782 and 0.748, in 7 days: 0.839 and 0.801, in 30 days: 0.780 and 0.757, P < .05.Compared with ABCD score, ABCD score combined with DWI and MRA can further improve the accuracy of prediction for cerebral infarction after TIA.