Objective Aiming to develop a distance-adaptive visual function self-examination system based on tablet computers and evaluate its accuracy.Methods Utilizing ArUco technology on a tablet device equipped with the camera,a system was developed to assess visual functions by identifying QR codes within a 2-meters range for real-time ranging.This system integrates various visual function tests,including visual acuity test(conventional visual acuity test and high-pass visual acuity test with varying contrasts),accommodative amplitude test,and visual field test at the foveal(5°).A total of 22 healthy subjects(44 eyes)participated in visual function assessments,with 6 subjects undergoing visual acuity tests at varying distances(1 m,1.25 m,1.6 m,2 m)and accommodative amplitude tests under both refractive correction and simulated undercorrection of-3.00D.The program distance and actual distance were compared,the consistency of visual acuity outcomes for identical optotype at different distances were assessed,the accommodative amplitude under refractive correction and undercorrection were analyzed,the repeatability of accommodative amplitude outcomes was evaluated using Intraclass Correlation Coefficient(ICC),and the contrast threshold and efficacy of visual field test outcomes were analyzed.Results The program distance and actual distance showed good agreement.High-pass visual acuity tests with the same contrast showed no significant differences at different distances(P?>?0.05),while conventional visual acuity tests showed significant differences at distances of 0.9 to 1.1 meters compared to other distances(P?

This study explored the variation of bursting force of multi-chamber infusion bag with different geometry size, providing guidance for its optimal design. Models of single-chamber infusion bag with different size were established. The finite element based on fluid cavity method was adopted to calculate the fluid-solid coupling deformation process of infusion bag to obtain corresponding critical bursting force. As a result, we proposed an empirical formula predicting the critical bursting force of one chamber infusion bag with specified geometry size. Besides, a theoretical analysis, which determines the force condition of three chamber infusion bag when falling from high altitude, was conducted. The proportion of force loaded on different chamber was gained. The results indicated that critical bursting force is positively related to the length and width of the chamber, and negatively related to the height of the chamber. While the infusion bag falling, the impact force loaded on each chamber is proportional to the total liquid within it. To raise the critical bursting force of in fusion bag, a greater length and width corresponding to reduced height are recommended considering the volume of liquid needed to be filled in.