Results 31 to 40 of about 12,707 (126)
笔者基于变分原理,推导了非线性的时域有限元电场计算方程和稳态热场有限元方程,分别利用商用软件Integrated Engineering Software和有温度分布解析解的轴对称电缆结构验证了编制程序的正确性,并利用该方法分析了含线性、非线性以及复合结构的应力管时的电缆终端电场和热场分布。分析结果表明,线性、非线性以及复合结构的应力管,通过适当的选择其结构和材料的参数都能很好的均匀终端的场强分布,但含非线性应力管的电缆终端的损耗和温升远小于含线性以及复合结构应力管的电缆终端 ...
连甲强, 解克佳, 唐东升
doaj
The effect of sedentary on surface electromyographic activities of lumbar muscles(久坐对脊椎肌肉sEMG信号的影响)
采集18名女性受试者在不同久坐时间下,颈夹肌和竖脊肌在最大用力收缩(MVC)过程中的表面肌电(surface electromyography, sEMG)信号,分别考察其初始1. 5 s的线性时频指标AEMG、MPF、非线性分析指标%DET的差异,以及全程MVC过程中MPF的变化趋势,以探讨久坐对脊椎肌肉活动水平和功能状态的影响.发现:在久坐前、久坐1.5 h、久坐3 h之后3种状态下,颈夹肌和竖脊肌在MVC的前1.5 s信号中,其时频信号AE-MG、MPF及非线性信号%DET均无明显变化;在1 ...
SONGChao(宋超) +3 more
doaj +1 more source
Validating the parental reflective functioning questionnaire ‐ infant version using a rasch model
Abstract Parental reflective functioning is the parent's ability to reflect on the psychological processes in their child and in themselves as a parent. Recently, an infant version of the Parental Reflective Functioning Questionnaire, PRFQ‐I, has been developed and validated using confirmatory factor analyses.
Anne Christine Stuart +4 more
wiley +1 more source
Routine 36‐week scan: diagnosis and outcome of abnormal fetal presentation
ABSTRACT Objectives First, to report the incidence of non‐cephalic presentation at a routine 36‐week ultrasound scan, the uptake and success of external cephalic version (ECV) and the incidence of spontaneous rotation from non‐cephalic to cephalic presentation.
M. Fitiri +5 more
wiley +1 more source
基于后退欧拉法和变分原理推导了非线性的时域有限元电场计算方程。利用时域有限元方法分析了含不同应力控制管时的电缆终端电场分布。分析结果表明,采用由电容性和非线性电阻性材料复合绝缘结构的应力控制管时,电缆终端的电场分布最为均匀。
宫瑞磊 +4 more
doaj
Abstract Background Radiological findings in the proximal sesamoid bones (sesamoids) are a persistent source of controversy at Thoroughbred sales, due to inconsistent classification and conflicting assignment of potential clinical importance. Objectives To define the prevalence of sesamoid findings on sales repository radiographs in yearling and 2‐year‐
Frances J. Peat +5 more
wiley +1 more source
ABSTRACT Objective To investigate the association between varying degrees of abnormality in the Doppler uterine artery pulsatility index (UtA‐PI) and adverse perinatal outcome. Methods This was a prospective study of women with a singleton, non‐anomalous pregnancy in whom UtA‐PI was measured universally in midpregnancy and who gave birth in Oxford ...
S. Dockree +6 more
wiley +1 more source
对于大型复杂空间钢结构,可靠的施工过程分析对保障施工安全性和钢结构安装质量具有重要意义。在传统施工过程分析与钢结构直接分析的基础上,提出一种考虑构件和安装模块初始缺陷以及变形累积的钢结构非线性施工过程分析方法。利用NIDA软件将该方法应用于成都某大悬挑钢桁架结构的施工过程分析中,确保了施工方案的可行性。同时,对比分析了非线性施工过程分析、一次成型分析和线性施工过程分析3种分析工况下结构关键节点位移及构件应力情况,并与施工实测值进行了比对。结果表明,一次成型分析与线性施工过程分析的位移较实测值偏小 ...
刘宏伟 +5 more
doaj +2 more sources
本文首先介绍了现行国家规范、规程及法规对超高层建筑必须进行弹塑性时程分析的规定,并介绍了目前弹性时程分析及弹塑性时程分析在超高层钢结构建筑抗震设计中应用的现状和不足之处。随后介绍了一种在国外工程界应用较多的弹塑性静力分析方法(Push-over Analysis),详细阐述了该方法的基本原理、计算模型、杆件单元刚度取值、计算程序、计算结果及分析。进而结合实际工程(某超高层钢-混凝土混合结构建筑),采用平面非线性地震反应分析程序(DRAIN-2DX)进行实例分析、
李达明
doaj
Abstract Large language models (LLMs) are a type of artificial intelligence (AI) that can perform various natural language processing tasks. The adoption of LLMs has become increasingly prominent in scientific writing and analyses because of the availability of free applications such as ChatGPT. This increased use of LLMs not only raises concerns about
Natalie Cooper +4 more
wiley +1 more source

