摘要：Ink-jet printing is a non-impact printing technology in which drops jetted from an orifice onto a designated *** technology can digitally transport fluids containing cells precisely onto desired substrates to construct three-dimensional *** order to obtain the stable uniform droplets,a stream is the key point of this ***,there are so many factors that affect the uniform droplet stream construction process:print parameters,material parameters,control method,etc.A good understanding of the various coupled transport processes that occur during bio-ink impact and spreading on bio-structure can improve the success of *** paper aims to obtain a good linear bio-structure with ink-jet printing ***,a typical droplet deposition process model is constructed;including droplet dynamics impact models and droplet diffusion cap ***,a model of successive droplet overlap,to form linear bio-structures,is ***,the finite element method is used to simulate the droplet impact,collision,and fusion ***,the main influencing factors of the continuous injection printing process,namely the time interval between consecutive droplets and the droplet contact angles,are *** alginate is selected as bio-ink to verify the theory,and it is found that a good linear bio-structure could be obtained if the printing parameters are controlled optimally,i.e.,if the initial contact angle is set as 60 degrees and the trigger frequency is set as 150 *** a proper printing speed and gel coating,a good survival rate of printed cells could be obtained.

摘要：The issue of designing a type of generalized Luenberger observers for matrix second-order linear (MSOL) systems was addressed in the matrix second-order framework. By introducing the concept of stable matrix pair for MSOL systems, sufficient and necessary conditions for the design of the type of generalized Luenberger observers were given under the assumption of controllability and observability of the MSOL system. Based on the proposed conditions and the right coprime factorization of the system, a parametric approach to the design of such type of observers was presented. The proposed approach provides all the degrees of design freedom, which can be further utilized to achieve additional system specifications. A spring-mass system was utilized to show the effect of the proposed method.

摘要：This paper develops fuzzy H∞ filter for state estimation approach for nonlinear discretetime systems with multiple time delays and unknown bounded disturbances. We design a stable fuzzy H∞ filter based on the Takagi-Sugeno (T-S) fuzzy model, which assures asymptotic stability and a prescribed H∞ index for the filtering error system. Sufficient condition for the existence of such a filter is established by solving the linear matrix inequality (LMI) problem. The LMI problem can be efficiently solved with global convergence using the interior point algorithm. Simulation exanples are provided to illustrate the design procedure of the proposed method.

摘要：由于网络传输带宽的限制,在网络传输中可能造成数据的丢失.对于同时具有测量数据和控制数据丢失的一类网络控制系统,研究H_2输出反馈控制问题.数据的丢失采用满足Bernoulli分布的二进制随机变量进行表述.利用矩阵不等式方法给出了H_2动态输出反馈控制器存在的充分条件,所设计的控制器使得闭环系统是均方意义下指数稳定并具有给定的H_2性能.采用SLPMM(Sequentially linear programming matrix method)给出相应的控制器求解算法.最后用数值仿真验证了所提出算法的可行性.

摘要：根据电力系统存在时滞的差异性,将控制器信号分为本地无时滞控制输入信号和广域异地多时滞控制输入信号两部分,建立了多时滞电力系统的模型。运用Lyapunov-Krasovskii泛函理论推导出了含有时滞分量的线性多时滞电力系统稳定判据,将控制问题转换为线性矩阵不等式的可行性问题,并采用模型降阶方法对原系统进行降阶,实现了含有多个时滞的广域输出反馈控制,并计算出了能够使闭环电力系统稳定的最大时滞时间。讨论了系统稳定判据中时滞分量与广域控制器参数之间的关系,以及对区域间振荡的控制效果。最后以两区域四机系统为例,用时域仿真的结果说明了本文所提出的多时滞控制方法的有效性。

摘要：The landing task of an aircraft under low aerodynamic pressure on carrier requires precise airplane control,A flight/thrust integrated control system(FTICS)with constant ad,actual angle of attack,is developed using LMI-based H∞*** typical single input/outputspecifications are translated into the weighting functions of an H∞output-feedback synthesis *** motiva-tion of the work is to improve the key performance of dy-namic tracking and air disturbance *** FTICS can keep the attitude andgle and the path angle un-changeable as the airplane is passing through the ramp at which the tracking radar doesnot work and the guidance signal is *** engineering application,an or-der-reduction method of the H∞controller is also pro-posed,Simulational results indicate that the system satis-fies the design requirements quite well.

摘要：In this paper, we examine the problem of designing power system stabilizer (PSS). A new technique is developed using particle swarm optimization (PSO) combined with linear matrix inequality (LMI). The main feature of PSO, not sticking into a local minimum, is used to eliminate the conservativeness of designing a static output feedback (SOF) stabilizer within an iterative solution of LMIs. The technique is further extended to guarantee robustness against uncertainties wherein power systems operation is changing continuously due to load changes. Numerical simulation ahs illustrated the utility of the developed technique.

摘要：This study evaluates the seismic response of an existing two stories RC building using non-linear analysis. The original model was resized and there were obtained two buildings designed under two different methodologies to fulfill the Venezuelan codes requirements for a high seismic hazard. An elastic analysis was applied to the original building in order to verify interstory drifts;the resizing building it was designed under requirements of strong column-wake beam condition. A third building was modeled according to the seismic displacement design procedure. It were performed non-linear static analysis and 2D and 3D dynamic analyses, obtaining capacity curves, structural ductility, structural performance point, global and interstory drifts for each building. Torsional effects for the resizing building were also computed from 3D analysis. In the original building it was obtained a weak seismic behavior, while resized buildings presented good seismic performance under the Limits States evaluated in this study.

摘要：The objective of the present article is to find an optimal design of a fan inlet to reduce the amount of noise radiated to the far field from the system. Against the gradient-based optimization algorithms, we employ here a method based on measure theory which does not require any information of gradients and the differentiability of cost function.