Energy storage systems used for the flexible grid connection of wind farms in terms of minute timescale usually consist of batteries. Due to the capacity constraints of batteries, when wind energy fluctuations exceed limits continuously, this type of energy storage system topology cannot present good performance. To solve this problem, this paper introduces a hybrid energy storage system (HESS) topology consisting of batteries and a hydrogen conversion system (HCS). To achieve a flexible wind farm grid connection with a minimum energy loss, a HESS control strategy is proposed to make full use of the advantages of the HCS capacity and battery energy conversion efficiency. The optimization goal is to minimize power fluctuations, battery life consumption, and energy loss. The energy conversion characteristics of the flexible wind farm grid-connection system are also analyzed. The simulation results show that compared with other strategies using only batteries, the operating strategy using the HESS with the same cost can combine the advantages of the battery efficiency and HCS power continuity to achieve a balance between the controlling energy loss and smoothing power fluctuations. INDEX TERMS Hydrogen conversion system, smoothing power fluctuations, hybrid energy storage system, flexible wind farm grid-connection.

Background and Objectives: With the increasing number of patients with febrile neutropenia (FN), voriconazole (VRC) has been widely used in hospitals for first-line treatment of FN. The study was designed for evaluating the influence of FMO3 mutation on the plasma disposition and adverse reactions of VRC in FN. Materials and Methods: A single-center observational study was conducted in the inpatient ward for 4 years. The genotypes of FMO3 and cytochrome P450 (CYP) 2C19 were detected by PCR-restriction fragment length polymorphism. Patients with neutropenia were screened according to the CYP2C19 metabolic phenotype and other inclusion criteria. Five days after empirical administration of VRC, blood concentrations of VRC and nitrogen oxides in patients' blood were determined by liquid chromatographyelectrospray tandem mass spectrometry (LC-ESI MS/MS). Serum parameters and clinical adverse reaction symptoms in the medical records were collected and statistically analyzed. Results: A total of 165 patients with neutropenia with the intermediate metabolic phenotype of CYP2C19 were screened. At the initial stage of oral VRC treatment, patients with the FMO3 E308G genotype had a poorer plasma disposal ability to VRC than those with the wide type of FMO3 (WT) genotype (p = 0.0005). Moreover, patients with the FMO3 E308G genotype were more likely to have adverse drug reactions and abnormal serum parameters after receiving VRC treatment. For example, the serum potassium level in the FMO3 E308G genotype group was significantly lower than that in the WT group (p = 0.028), the abnormal level of total bilirubin in the FMO3 E308G genotype group was significantly higher than that in the WT group (p = 0.049), and the aspartate aminotransferase level in the E308G group was significantly higher than that in the WT group (p = 0.05). The incidence of atopic dermatitis and visual impairment in the FMO3 E308G genotype group was 67 and 75%, respectively, and the incidences of peripheral neuroedema, headache, and diarrhea were 57, 50, and 60%, respectively, which were significantly different from those in the WT group. Conclusion: FMO3 E308G reduces the activity of the FMO3 enzyme by decreasing the metabolic ability of VRC, which increases the plasma concentration of VRC and may also lead to adverse reactions in patients with FN.

An improved method for the inertial measurement unit (IMU) calibration of coarse alignment for the low-accuracy attitude heading reference system (AHRS) is proposed in this paper. The sensitivities of the Euler angles with respect to the inertial sensor biases are studied based on the analytic coarse alignment principle, and the errors of earth rotation rate and local gravity in the body frame caused by initial attitude error are analyzed. Then, an improved analytic coarse alignment algorithm with accelerometer and gyro bias calibration in an arbitrary three-position is proposed. Simulation and experiment results show that the novel method can calibrate accelerometer and gyro biases, reduce Euler angle attitude error, and improve navigation precision in practical applications. Moreover, this method can be applied to other low-accuracy inertial navigation systems.

Currently, the development of floating wind turbines and wave energy converters (WECs) is both facing the challenge of high cost-of-energy (CoE). A promising way to reduce the CoE is to employ combined wind and wave energy concepts because they can share the same floating platform, mooring systems, and electrical cables and thus reduce the construction cost. Several combined concepts with floating horizontal axis wind turbines (HAWTs) have been proposed and studied. Compared to floating HAWTs, floating vertical axis wind turbines (VAWTs) have a good potential for CoE reduction.Therefore, this study proposes a novel combined wind and wave energy concept, which consists of a spar-type floating VAWT and a torus-shaped point absorber WEC. This combined concept utilizes the relative heave motion between the torus and the spar buoy to harvest wave energy. Fully coupled simulations under turbulent wind and irregular waves are carried out to evaluate its power performance and to assess the effect of the additional torus on the dynamic behavior of the floating VAWT. The results indicate that introducing the WEC contributes to the total power production while causing limited impacts on the power production and dynamic responses of the floating VAWT. The proposed combined concept is promising.

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