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The use of distributed photovoltaics (PVs) on a large scale often causes voltage over-limit problems in distribution networks. This paper proposes a distributed photovoltaic cluster collaborative optimization voltage control strategy based on an improved community algorithm to address the issue of centralized control being unable to respond quickly to the randomness of distributed photovoltaics and the difficulty of achieving overall coordination with local control. First, by improving the community algorithm, the division of reactive and active clusters, considering the power balance and node coupling degree, is realized. Then, the cluster-coordinated voltage control strategy is proposed by making full use of the power control ability of a photovoltaic inverter. Finally, a voltage regulation ability evaluation index is proposed to assess the node regulation ability within the cluster and select key nodes. This effectively reduces the number of control nodes. The simulation analysis of the improved IEEE 69 distribution network shows that the proposed voltage control strategy can mitigate the issue of voltage over-limit in high-permeability distributed photovoltaic access distribution and enhance the photovoltaic consumption capacity. [ABSTRACT FROM AUTHOR]

In this paper, a kind of implantble passive wireless surface acoustic wave (SAW) sensor and its reader are developed to measure the operation temperature of high voltage crossed-linked cable core. A small type SAW temperature sensor is embedded into cable intermediate joint. A radio frequecny transceiver of the reader based on discrete devices is optimally designed to achieve high signal-to-noise ratio and receiving sensitivity. The characteristic of resonant frequency and temperature of SAW sensor is determined by frequency scan method. Through AC withstand voltage and temperature rise test of 110kV cable, it proves that the prototype can accurately measure the operation temperature of 110kV cable core in intermediate joint under high operation temperature and strong electromagnetic environment.

Introduction: Regional citrate anticoagulation is a preferred option for renal replacement therapy in critically ill patients. However, current implementations ignore individual differences that may exist in the fluctuation of patients' ionized calcium levels. To address this problem, individualized citrate and calcium supplementation models were established based on the pharmacokinetic and clearance characteristics of citrate, and an automated regional citrate anticoagulation system was built with these models as its core to facilitate the treatment of clinical patients. This study was designed to preliminarily evaluate the safety and efficacy of this system, the SuperbMed ® RCA-SP100 automated regional citrate anticoagulation system, in prolonged intermittent renal replacement therapy., Methods: Seven patients undergoing prolonged intermittent renal replacement therapy completed treatment with the SuperbMed ® RCA-SP100 system. In vivo and in vitro ionized calcium levels were measured every hour before and after the start of dialysis. The accuracy and alarm sensitivity of the pumps were also monitored., Results: During seven treatments, the average extracorporeal ionized calcium level was 0.34 ± 0.02 mmol/L, and the mean ionized calcium level in vivo was 1.09 ± 0.07 mmol/L. No patient required intervention, and there was no filter coagulation. The pumps all had an absolute accuracy less than 5%, and alarms could be triggered precisely., Conclusions: We reported on an automated system that allows for individualized citrate and calcium supplementation in prolonged intermittent renal replacement therapy and enables the precise and secure implementation of regional citrate anticoagulation.

Background: Growing evidence suggests that concurrent ischaemic stroke (IS) exacerbates the prognosis of patients with dilated cardiomyopathy (DCM) and that this effect may be further influenced by sex. However, the exact effect of sex remains unclear. This study aimed to explore the effects of the relevant risk factors on the prognosis of patients with DCM and concurrent IS. Considering the sex differences in DCM, this study further investigated the impact of concurrent IS on the prognosis of men and women with DCM., Methods: A total of 632 patients with DCM enrolled between 2016 and 2021 were included in this study. Clinical data were obtained from medical records, and all participants were followed up in the outpatient clinic or by telephone for at least 1 year. A Cox proportional hazards model and Kaplan-Meier curves were used to evaluate the effects of concurrent IS on the prognosis of patients with DCM., Results: Patients with DCM complicated with IS (DCM-IS) had significantly lower cumulative survival rates than patients with DCM without IS (non-IS) (74.6% vs. 84.2%, χ 2 = 6.85, p = 0.009). Additionally, IS was associated with greater risks of death and heart transplantation (HTx) in men (75.8% vs. 85.1%, χ 2 = 5.02, p = 0.025), but not in women (71.0% vs. 81.5%, χ 2 = 1.91, p = 0.167)., Conclusions: This large-scale multicentre prospective cohort study demonstrated a poorer prognosis in patients with concurrent DCM and IS, particularly among men. Patients with DCM should not be overlooked in IS screening, emphasis should be placed on the occurrence of IS in patients with DCM. Early and proactive secondary prevention of cerebrovascular diseases might improve the prognosis of DCM patients. More intervention studies focusing on men with DCM complicated with IS should be prioritised., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2024 The Author(s). Published by IMR Press.)