Results 21 to 30 of about 861 (102)
Occurrences of dust storms and long‐distance movement of dust across landscapes is constantly increasing in south Asia. This dust is expected to have profound impact on vegetation health and sustainability as dust may contribute to nutrient budgets of the forest ecosystems, while it could impart various stresses to the plants.
Shree P. Pandey +2 more
wiley +1 more source
A FEM-DEM Coupled Multiscale Analysis Method for Study of Mechanical Behaviors of Concrete [PDF]
混凝土是一种多相复合材料,由于材料非均匀各向异性的特点,其力学性能十分复杂,但作为建筑结构中最广泛使用的材料之一,研究能够可靠高效分析其力学行为的数值模拟方法有非常重要的意义。有限元法(FEM)目前主要集中于对混凝土宏观力学行为的模拟,但是由于基于连续介质力学假设,对混凝土开裂后细观力学性能的分析较为困难。离散元法(DEM)虽然对于混凝土的细观开裂和局部破坏有较好的模拟效果,但是由于计算耗时过大,限制了其在工程问题的应用范围。因此,本文想开发一种结合两者优点的数值模拟方法 ...
刘轲奇
core
Wall-thickness reduction of AP1000 primary coolant pipes subjected to cold roll-forming [PDF]
A modified Johnson-Cook model was proposed based on the true stress-strain data of 316LN stainless steel and it was successfully used to describe the deformation characteristic of the steel at room temperature and low strain rate.
WANG Peng +3 more
core +1 more source
Abstract Prior research in health equity, including food security, indicates that disadvantaged groups, such as women with limited resources, face many obstacles in achieving food security. One of the first of its kind to draw on intersectionality and the social determinants of health frameworks, this study identified and tested gender differences in ...
Farzaneh Barak +2 more
wiley +1 more source
Refinement and Calculation Method for Stiffener Scheme for Topside Joints of Offshore Step-Up Station [PDF]
[Introduction] The topside module of an offshore step-up station usually has numerous tube-I section joints with complicated structure, which cannot be checked by general structural design software. Hence, a feasible checking design method and refinement
Fangyuan CHENG, Xuan CHEN, Zuopeng WEN
core +1 more source
结合材性试验获得的不锈钢母材和焊缝金属材料本构关系模型,使用ANSYS有限元软件对奥氏体型S30408不锈钢角焊缝连接的承载性能进行了非线性有限元模拟,并将模拟结果与不锈钢正面角焊缝连接试件和侧面角焊缝连接试件拉伸试验结果进行了对比,验证了有限元模型的有效性。利用经试验验证的有限元模型对角焊缝承载力影响因素进行了参数分析,并将有限元模拟值与按照美国规范SEI/ASCE 8-02、欧洲规范EN 1993-1-4,以及中国《不锈钢结构技术规程》(CECS 410:2015)计算求得的规范设计值进行了对比 ...
张有振 +4 more
doaj
采用数值模拟方法对波纹腹板剪切屈曲破坏的钢管混凝土翼缘曲梁承载力问题进行了研究。运用有限元分析软件,建立跨中集中荷载作用下的矩形钢管混凝土翼缘-波纹腹板曲梁(curved girders with rectangular concrete-filled tubular flange and corrugated web, CG-RCFTF-CW)的有限元模型。利用有限元建模方法分别对平翼缘波纹腹板直梁和钢管混凝土翼缘平腹板曲梁建立了相应的有限元模型 ...
杜栖云, 邵永波, 邓利霞
doaj
Study of GHz Surface Acoustic Wave Humidty Sensor Using Nanostructured Materials [PDF]
随着物联网应用的不断扩展,需要大量传感器节点组成无线传感网络以实现未来万物互联的目标。其中,湿度测量器件在智能家居、气象、工业控制等领域是最为广泛和基础的传感器节点。为了实现无线传感网络,现有的电阻、电容型传感器件需要独立的电源系统持续供电,而在电池容量有限的条件下,器件需要采用占空比方式工作,即在高功耗的传感工作状态之间加入待机模式,以减小传感器节点的总功耗。由于待机模式的存在,无法对整个环境状态进行实时、无缝的检测,且由于构成节点的传感元件一般属于相对高功耗的器件,电池寿命始终有限。声表面波 ...
刘源
core
Design and Analysis of Vibration Energy Collector Based on MEMS [PDF]
微能量采集器中电容式采集器易与IC工艺集成,目前已知的传统电容式微能量采集器都需要外加电压,这在很大程度上限制电容式微能量采集器的实际使用。针对该问题,基于微机电系统工艺,提出功函数原理电容式微能量采集器,给出采用两种不同金属作为电容极板电极的采集器原理模型设计,并建立相应系统数学模型,计算大致悬臂梁长度的设置与范围,使用有限元模拟软件AnSyS进行进一步分析与优化设计。在此理论基础上设计出的新型振动能量采集器,可克服传统电容式微能量采集器需要外界提供电源这一缺点。The traditional ...
李林, 郭隐彪, 陈旭远
core +1 more source
为了更深入了解金属蒙皮支撑连续檩条在整体蒙皮结构中所起的作用,为今后我国对连续檩条以及蒙皮结构的设计、计算提供依据,通过足尺模型试验和有限元模型的分析,研究了蒙皮支撑冷弯薄壁连续型钢檩条模拟风吸力作用的承载力。利用有限元程序ANSYS建立了带有非线性弹簧单元模拟自攻螺钉这一符合实际连接状况的有限元模型,与足尺试验模型的失稳模式、荷载-位移曲线、连接强度以及连接刚度的规律等相对比,验证了有限元模型的合理性、有效性及适用性。
潘宇 +6 more
doaj

