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Precisely determining how cables distribute their current-carrying capacity and temperature field is crucial for the dependable and cost-effective functioning of power grids. Firstly, the power cable structure and the advantages and disadvantages of different laying methods are analyzed in detail. Secondly, the theoretical model of current-carrying capacity calculation and temperature field of power cables, including heat convection, heat conduction, and heat radiation, is constructed, and the method for calculating cable current-carrying capacity, relying on the double-point chordal interception method, is suggested. Then, the COMSOL multiphysics 6.2 finite element simulation software is utilized to create a simulation model that aligns with the real cable laying technique. Finally, the current-carrying capacity and temperature field of power cables are simulated and analyzed for different arrangements of power cables in three laying modes, namely directly buried, row pipe, and trench. The simulation results show that the cable laying method greatly affects the cable's carrying capacity; the more centralized the cable distribution, the smaller the flow. The method can be realized in different ways of laying power cables in the real-time rapid calculation of flow as the actual laying of power cables has an important reference and reference significance. [ABSTRACT FROM AUTHOR]

The urbanization of suburbs has a significant impact on ocular health, however, the effect of this phenomenon on the epidemiology of eye diseases in the sub-urbanization region of China remains unclear. In this context, the population-based Beichen Eye Study (BCES) was conducted in the Beichen District of Tianjin, China. This article aims to summarize the background, design scheme and operation process of the study. The Chinese Clinical Trial Registry number was ChiCTR2000032280. In total, 8218 participants were randomly selected by a multi-stage sampling method. After their qualification was confirmed, participants were mainly invited to a centralized clinic via telephone interviews after promotion of the study in the community. Examinations included a standardized interview, anthropometric assessment, autorefraction, ocular biometry, visual acuity, anterior and posterior segment examinations, dry eye disease (DED), intra-ocular pressure, visual field testing, gonioscopy, and imaging of anterior segment, posterior segment, fundus, and optic disc. A peripheral venous blood sample was also collected for biochemical testing. For observational purposes, a community-based type II diabetes mellitus management mode was created and assessed for its effect in preventing the progression of diabetic retinopathy (DR). Of the 8,218 residents, 7,271 were eligible for inclusion, and 5,840 (80.32%) subjects were enrolled in the BCES. Most of the participants were female (64.38%) with a median age of 63 years, and 98.23% representing Han Chinese descent. Conclusions: This study provides insights into the epidemiological characteristics of major ocular diseases and their moderators in a suburbanized region of China. [ABSTRACT FROM AUTHOR]