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Summary: This paper investigates the interruption capability with the aid of a parallel capacitor branch and exploits the single current direction through a series thyristor with the DC system. Two DC current interruptions are introduced by providing superimposed oscillatory currents. The first one is that the capacitor branch (capacitor and inductor) is continuously connected in parallel with the system where the capacitor is charged from the system during the normal operation. Due to fault occurrence, the capacitor branch including an inductor produces an oscillatory current that can make zero crossing through the series thyristor. However, the interrupting current is unfortunately after the second oscillatory peak current that the fault resistance can damp the oscillatory current. By changing the charged capacitor polarity, the second breaking concept is introduced depending on a precharged capacitor by the system voltage and then injecting the oscillatory current using a self‐triggered additional thyristor. The current interruption initiation is attained using the DC current raising. The interruption performance is evaluated using a thyristor‐based converter DC system. [ABSTRACT FROM AUTHOR]

Objectives. The objective of this study is to explore the gender discrepancy in patients with traumatic brain injury (TBI). Methods. A retrospective analysis of Qatar Trauma Registry (QTR) was conducted among patients (age ≥14y) who were hospitalized with TBI. Data were collected and analyzed based on the gender and age. Results. Over 5 years (2014-2019), 9, 309 trauma patients (90% males and 10% females) were admitted to the trauma center. Of these, 1, 620 (17.4%) patients were hospitalized with TBI (94% males and 6% females). Motor vehicle crash was the main mechanism of injury (MOI) in females, and fall from height was predominant among males. Subdural hematoma (SDH) was the more frequent type of TBI in both genders, but it was more prevalent in male patients ≥55 years. Injury severity score, Glasgow coma scale, and head abbreviated injury score were comparable between males and females. The length of stay in the ICU and hospital and mortality were similar in both genders. However, mortality was higher among males ≥55 years when compared to 14-54 years within the same gender (21% vs. 12%, p = 0.002). The crude and adjusted odds ratio did not show that gender is a significant predictor of mortality among TBI patients. Conclusions. Although the incidence and MOI of TBI show significant differences between male and female patients, the severity and outcomes are comparable. [ABSTRACT FROM AUTHOR]

Summary: During the last years, the electricity networks worldwide have rapidly developed, especially with integrating many types of renewable energy sources (RESs). The optimal operation is an opportunity to increase the penetration level of stochastic RESs into the power grid to maximize energy efficiency. Generally, the optimal power flow (OPF) problem is a highly complex, non‐convex, and non‐linear optimization problem. The complexity of the OPF problem is further increased as stochastic RESs are incorporated into the network. This paper presents an effective solution to the OPF problem for a traditional power generation with stochastic RESs. For solving this problem, chaotic Bonobo optimizer (CBO) is proposed in this paper based on the Chaos Theory to avoid the stuck in the local minimum by applying the original Bonobo optimization (BO). The performance of BO is enhanced using the chaotic maps sequences technique to enhance its global search capability and prevent getting stuck into local solutions. Uncertainty of the output power generated by RESs is forecasted based on probabilistic models. To minimize the total operating cost, the direct, underestimation, and overestimation costs of RESs are considered. Three different objective functions are considered, minimizing total operating cost, emissions, and power losses. Moreover, a carbon tax is incorporated in the objective function problem to minimize carbon emissions. The proposed OPF model and CBO technique are verified on the modified IEEE‐30 and IEEE‐57 bus test systems to confirm the superiority and effectiveness of the proposed CBO to achieve the optimal solution. The simulation results prove the efficiency and robustness of CBO for finding the best solution to the OPF problem with stochastic RESs. [ABSTRACT FROM AUTHOR]