摘要：Microfluidic channels are at micrometer scales;thus,their fluid flows are laminar,resulting in the linear dependence of pressure drop on flow rate in the length of the *** ratio of the pressure drop to flow rate,referred to as resistance,depends on channel size and dynamic ***,a microfluidic chip is analogous to an electric circuit in design,but the design is adjusted to optimize channel ***,whereas voltage loss is negligible at the nodes of an electric circuit,hydraulic pressure drops at the nodes of microfluidic chips by a magnitude are comparable to the pressure drops in the straight ***,we prove by experiment that one must fully consider the pressure drops at nodes so as to accurately design a precise microfluidic *** the process,we numerically calculated the pressure drops at hydraulic nodes and list their resistances in the range of flows as *** resorted to machine learning to fit the calculated results for complex ***,we obtained a library of node resistances for common junctions and used them to design three established chips that work for single-cell analysis and for precision allocation of solutes(in gradient and averaging concentration microfluidic networks).Endothelial cells were stimulated by generating concentrations of adriamycin hydrochloride from the last two microfluidic networks,and we analyzed the response of endothelial *** results indicate that consideration of junction resistances in design calculation brings experimental results closer to the design values than *** approach may therefore contribute to providing a platform for the precise design of organ chips.

摘要：隔离式双向全桥DC-DC变换器(isolated bidirectional dual-active-bridge DC-DC converter,IBDC)采用单移相控制时会产生较大的回流功率和电流应力,导致损耗增加。该文通过建立IBDC采用单和双重移相控制时的输出功率及回流功率数学模型,推导出回流功率与移相比及输入/输出电压调节比之间的数学关系,提出一种以回流功率最小为目标的双重移相回流功率优化控制策略。该控制策略根据传输功率及输入/输出电压调节比所处的不同范围,采用分段优化方法,得出各范围内的最优内移相比。通过仿真计算,对比研究该优化策略与单移相控制下的回流功率曲线。文中给出详细的优化控制算法和系统控制方案,并基于该方案设计制作实验样机。实验结果验证了所提出双重移相回流功率最优控制策略的有效性与可行性。