Single-phase distribution approach is a new lowvoltage power distribution technology. It is significant for reducing distribution line losses, improving power supply reliability and assuring voltage quality. RMS current method is adapted. In a typical residential community, distribution transformer loss, low voltage line loss and investment in equipment single-phase and three-phase distribution methods is calculated, compared and analyzed. It is proved that the full extension high-voltage power line is an effective means to reduce the running loss. And Single-phase power distribution method has good economic and social benefits, which can be adapted and promoted according to the local conditions.

No abstract

the aim of the present study was to investigate the value of the use of fluorine-18 ( 18 F)-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) vs. magnetic resonance imaging (MRI) for the diagnosis of and differentiation between benign and malignant lesions in the spinal canal. For this purpose, a retrospective analysis was performed on the use of MrI and 18 F-FDG PET/Ct from January, 2017 to December, 2020, and the final diagnosis was obtained by performing a post-operative pathological examination or following a tissue biopsy (gold standard). The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the two examination techniques were calculated and comparisons between them were made. The PET metabolic parameters, maximum standardized uptake value (SUVmax), peak standardized uptake value (SUVpeak), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) in the benign and malignant groups were calculated and compared, and the corresponding ROC curves were plotted. A total of 58 patients were enrolled, including 30 patients with malignant and 28 with benign lesions. The specificity of MRI was significantly higher than that of PET/CT (P<0.05). The sensitivity and negative predictive value of PET/Ct were higher than those of MRI, although with no significant difference (P>0.05). The mean ± tandard deviation values of the PET metabolic param-