在动态仿真中风电场模型的简化

分别针对异步风力发电机组风电场和双馈风力发电机组风电场,研究在动态仿真中风电场模型的简化.以风力机和发电机具有相同或相近运行点为风电场动态模型简化原则,依据尾流效应影响对风电场进行区域划分,将风力发电机组合并简化,建立风电场整体简化模型.针对风力发电机组类型和风速变化、电力系统短路的动态过程,通过仿真对比详细模型和不同程度的简化模型,验证各种简化模型的适用性,提出在动态仿真中风电场简化模型的应用建议.     

Collective Organization Behaviors of Multi-Cell Systems Induced by Engineered ECM-Cell Mechanical Coupling

Cells in vivo are surrounded by fibrous extracellular matrix (ECM), which can mediate the propagation of active cellular forces through stressed fiber bundles and regulate various biological processes. However, the mechanisms for multi-cellular organization and collective dynamics induced by cell-ECM mechanical couplings, which are crucial for the development of novel ECM-based biomaterial for cell manipulation and biomechanical applications, remain poorly understood. Herein, the authors design an in vitro quasi-3D experimental system and demonstrate a transition between spreading and aggregating in collective organizational behaviors of discrete multi-cellular systems, induced by engineered ECM-cell mechanical coupling, with the observed phenomena and underlying mechanisms differing fundamentally from those of cell monolayers. During the process of collective cell organization, the collagen substrate undergoes reconstruction into a dense fiber network structure, which is correlated with local cellular density and consistent with observed enhanced cells' motility; and the weakening of fiber bundle formation within the hydrogel reduces cells’ movement. Moreover, cells can respond to the curvature and shape of the original cell population and form different aggregation patterns. These results elucidate important physical factors involved in collective cell organization and provide important references for potential applications of biomaterials in new therapies and tissue engineering.     

纤维支撑剂团静态沉降速度计算方法

水力压裂过程中,脉冲注入含纤维的支撑剂团可以有效保持其在裂缝输送沉降过程中的完整性,从而形成柱状支撑裂缝.通过实验再现了纤维支撑剂团静态沉降过程中的完整性,将压裂液-纤维-支撑剂三相混合物处理为单相流体,通过修正液相的流变性获得混合物的物性,考虑纤维支撑剂团在静态沉降过程中所受的重力、浮力、壁面摩擦力和绕流阻力,建立其...     

(2+1)维mKdV方程dromions相互作用的研究

从两个线孤子解出发，可以得到双线性形式2 1维mKdV方程的某个势函数的dromion解。该dromion解在所有方向都是局域的。两个dromion之间的相互作用通过图形分析的方法进行了详细研究。依据参数的不同选择，该相互作用可以是弹性的也可以是非弹性的。     

《预包装食品标签通则》实施情况研究及管理建议

目的 对GB 7718-2011《预包装食品标签通则》的实施情况开展评价,以了解标准实施情况及标准使用者对GB 7718-2011的建议,为GB 7718-2011的修订提供依据.方法 针对标准实施情况及重点内容对食品生产者、食品经营者、市场监管者、检测机构人员等标准使用者开展调查.结果 研究共2 487人参与,实际有...