Cell Generator: A Self‐Sustaining Biohybrid System Based on Energy Harvesting from Engineered Cardiac Microtissues

Biohybrid soft robotic devices present unique advantages for designing biologically active machines that can dynamically sense and interact with complex bioelectrical signals. Here, a controllable cell‐based machine is developed that harvests energy from arrays of beating cardiomyocytes to generate electricity for biomedical microscale robotic applications. The “Cell Generator” device is based on an array of piezoelectric microcantilevers wrapped with 3D patterned cardiac cells. Spontaneous contraction of the engineered cardiac constructs provides the source of mechanical energy for electricity generation. It is demonstrated that a single “Cell Generator” unit with 40 cantilevers can output peak voltages of ≈70 mV, and a larger array of 540 cantilevers can directly generate a pulsed output as high as ≈1 V. When integrated with an electrical rectification and storage circuit, it is further shown that the “Cell Generator” can provide functional outputs and work as a self‐powered neural stimulator to evoke action potentials in cultured neuronal networks. This demonstration of “Cell Generator” technology provides an innovative perspective of exploiting live biological powering system on biomedical microscale robotic devices in the human body.     

基于人工鱼群的中继卫星多用户检测方法

随着航天技术的发展,未来的中继卫星系统需要为多个用户航天器提供码分多址通信服务。因此需要采用多用户检测技术来抑制多个用户航天器信号之间的多址干扰。文中将人工鱼群优化算法引入到中继卫星系统多用户检测中,通过模拟人工鱼群觅食过程中的觅食行为、聚集行为以及尾随行为,利用人工鱼群的迭代优化,实现多址干扰的最小化。为加快人工鱼群算法的收敛速度,文中将解相关多用户检测的结果作为人工鱼群算法的迭代初值。结果表明,基于人工鱼群算法的多用户检测方法误码率在信噪比为10 dB时可以达到10 ^-6数量级,在误码率、远近效应以及用户容量等方面的性能优于传统的多用户检测方法。     

基于混沌DESAPSO算法的无人机三维航迹规划

粒子群(PSO)算法易陷入局部最优,将其运用于无人机三维航迹规划会导致航迹品质不高,针对这一问题,提出了将差分进化(DE)算法、模拟退火(SA)算法嵌入PSO算法中,构成混沌差分进化模拟退火粒子群(DESAPSO)算法,从三个方面提高了航迹品质:一是利用DE算法的变异、交叉及竞争选择增加种群多样性;二是利用SA算法概率突跳能力跳出局部最优解;三是对PSO算法参数进行混沌优化,进一步增强种群多样性.仿真结果表明:混沌DE-SAPSO算法改进航迹品质效果明显,获得了满意的无人机三维航迹.     

幅值比约束下稀布阵的旁瓣抑制混合算法

针对非均匀稀布圆环阵的旁瓣抑制问题提出了一种基于粒子群算法和二阶锥规划算法的混合算法。该混合算法结合两种算法的优势,将粒子群算法作为全局搜索器进行阵元位置的优化,二阶锥规划算法作为局部搜索器进行阵元权值的优化,能够获取较低的峰值旁瓣电平。该算法同时引入相邻阵元最小间距的约束,优化了算法的搜索空间,提高了寻优效率。最后,考虑到阵列天线系统的可实现性,给出了动态幅值比约束下的混合算法。与粒子群算法和参考文献方法的对比实验结果表明:本文算法可进一步降低稀布圆环阵的旁瓣电平,仿真数据验证了算法的有效性和天线系统的可实现性。     

QoE-aware video distribution mechanism in FiWi

The mismatch of transmission ability causes the discontinuous transmission of video services in fiber-wireless access network,aimed at this problem,an QoE-aware video distribution mechanism was proposed.According to the structural characteristics of fiber-wireless access network,link state information and scalable video coding structure was considered,a QoE evaluation mode was established,and the particle swarm optimization algorithm was used to select optimal video transmission rate.Then the node transmission capacity and the node matching degree was analyzed,transmission path for the services was selected,so as to ensure the reliable transmission of services.The results show that the proposed mechanism can effectively improve the utilization rate of network resources and reduce network congestion while improving the quality of the user experience.     

基于改进灰狼优化算法的移动机器人路径规划

针对移动机器人避障路径规划问题,在基本群智能算法灰狼优化算法的基础上,提出改进灰狼优化算法,测试函数证明了算法的稳定性和收敛性,进而将其首次应用于移动机器人避障路径规划问题,通过对改进灰狼优化算法的移动机器人避障路径进行研究,并与基本灰狼优化算法、粒子群算法、遗传算法比较,仿真结果证明了算法的稳定性和收敛性,对路径规划领域有十分重要的研究意义。     

Microchemomechanical Systems

The development of microchemomechanical systems (MCMS) as an analogy to microelectromechanical systems (MEMS) is reviewed, with the distinction that the mechanical actuation of microscale structures is effected by chemical cues as opposed to electricity. The intellectual motivation to pursue MCMS, or the creation of integrated chemical‐stimuli‐responsive devices, is that such structures are widely observed in nature. From a practical standpoint, since chemicals can readily diffuse and produce changes over large distances, this approach is especially attractive in enabling wireless and autonomous devices at small size scales.     

数字电路测试向量自动生成系统的比较

把遗传算法与蚂蚁算法运用于组合电路向量自动生成系统,并比较两者性能的优劣,根据实验结果进一步提出优化组合方案,将此方案应用于同步时序电路的测试向量自动生成系统中。提出一种优化的数字电路的测试向量自动生成系统。这个系统集合了蚂蚁算法和遗传算法的优点,使系统能在更短时间生成更小的测试集,而又能达到原先的故障覆盖率。     

重构分数低阶协方差的子空间拟合测向算法

基于重构的分数低阶矩阵,提出了重构分数低阶协方差的多重信号分类测向算法和信号子空间拟合测向算法.为了快速求解所提出的测向算法,设计了一种可进行多维搜索的自适应差分粒子群优化算法.利用粒子群算法和差分进化算法的优点,可以获得测向问题的全局最优解.Monte-Carlo仿真证明了所提测向算法可有效分辨相干源,并且其检测性能优于已有的一些经典算法.