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Optimal design for split-and-recombine-type flow distributors of microreactors based on blockage detection

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Chinese Journal of Chemical Engineering 2016年第7期24卷 897-903页

作者： Lin Wang Xianzuo Kong Yongsheng Qi department of control Engineering Inner Mongolia University of Technology

In order to increase the productivity of microreactors, the parallelization of the microreactors is required. The performances of flow distributors can affect the product yield and fault detection ability when blockage *** this research, an optimal design method to calculate the channel diameters and to determine the flow sensor location is derived based on mass balance and pressure balance models of split-and-recombine-type flow distributors(SRFDs). The model accuracy is verified by experiment data. The proposed method is applied to optimal design of SRFDs under constant flow rate operation conditions. The maximum angle difference between normal and blockage conditions at one sensor to those at the other sensors is set to be the objective function and the uniformity of flow distribution in microreactors under normal condition is also required. The diameters of each pipe in SRFDs are selected as the design variables. Simulated annealing algorithm is used to solve the optimization problem. The effectiveness of the optimal design results is demonstrated by fluid dynamics simulations. The results show that using the optimal channel diameters of SRFDs, the pressure drop in SRFD section is lower than that of the microreactor section. Meanwhile, in the case studies, only a few sensors that are located inside the SRFDs can easily detect the blockage abnormal condition in the parallelized microreactor system.

关键词： Optimal designSplit-and-recombine-type flow distributorsMicroreactorsMicrochannelsBlockage

Fully Pipelined Soft Vector Processor as a CPU Accelerator

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Chinese Journal of Electronics 2017年第6期26卷 1198-1205页

作者： PANG Yeyong WANG Shaojun PENG Yu PENG Xiyuan department of Automatic Test and control Harbin Institute of Technology

FPGA based soft vector processing accelerators are used frequently to perform highly parallel data processing tasks. Since they are not able to implement complex control manipulations using software, most FPGA systems now incorporate either a soft processor or hard processor. A FPGA based AXI bus compatible vector accelerator architecture is proposed which utilises fully pipelined and heterogeneous ALU for performance, and microcoding is employed for reusability. The design is tested with several design examples in four different lane *** with Central processing unit(CPU), Digital signal processor(DSP), Altera C2H tool and Open CL SDK implementations, the vector processor improves on execution time and energy consumption by factors of up to 6.6 and 6.4 respectively.

关键词： FPGA Vector processor Microprocessor Accelerator

Three-dimensional finite-time cooperative guidance for multiple missiles without radial velocity measurements

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Chinese Journal of Aeronautics 2019年第5期32卷 1294-1304页

作者： Teng LYU Chuanjiang LI Yanning GUO Guangfu MA department of control Science and Engineering Harbin Institute of Technology

In order to simultaneously attack a target with impact angle constraint in threedimensional(3-D) space, a novel distributed cooperative guidance law for multiple missiles under directed communication topologies is proposed without radial velocity measurements. First, based on missiles-target 3-D relative motion equations, the multiple missiles cooperative guidance model with impact angle constraint is constructed. Then, in Line-of-Sight(LOS) direction, based on multiagent system cooperative control theory, one guidance law with directed topologies is designed with strict proof, which can guarantee finite time consensus of multiple missiles' impact times. Next, in elevation direction and azimuth direction of LOS, based on homogeneous system stability theory and integral sliding mode control theory, two guidance laws are proposed respectively with strict proof, which can guarantee LOS angles converge to desired values and LOS angular rates converge to zero in finite time. Finally, the effectiveness of the designed cooperative guidance law is demonstrated through simulation results.

关键词： 3-D cooperative guidance Directed communication topologies Finite time Impact angle constraint Radial velocity measurements

A distributed cooperative guidance law for salvo attack of multiple anti-ship missiles

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Chinese Journal of Aeronautics 2015年第5期28卷 1438-1450页

作者： Zhang Youan Wang Xingliang Wu Huali department of control Engineering Naval Aeronautical and Astronautical University

The consensus problem of impact time is addressed for multiple anti-ship missiles. A new distributed cooperative guidance law with the form of biased proportional navigation guidance （BPNG） is presented. The proposed guidance law employs the available measurements of relative impact time error as the feedback information to achieve the consensus of impact time among mis- siles and, by exploiting the special structure of the biased cooperative control term, it can handle the seeker＇s field-of-view （FOV） constraint. The proposed scheme ensures convergence to consensus of impact time under either fixed or switching sensing/communication network, and the topological requirements are less restrictive than those in the existing results. Numerical examples are provided to illustrate the effectiveness of the proposed guidance law.

关键词： Cooperative Distributed Field-of-view constraint Missile guidance Missile trajectory control

H_-/H_∞ fault detection filter design for interval time-varying delays switched systems

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Journal of Systems Engineering and Electronics 2016年第4期27卷 878-886页

作者： Jiawei Wang Yi Shen Zhenhua Wang department of control Science and Engineering Harbin Institute of Technology

The problem of the robust fault detection filter design for time-varying delays switched systems is considered in the framework of mixed H-/H∞. Firstly, the weighted H∞ performance index is utilized as the robustness performance, and the H- index is used as the sensitivity performance for obtaining the robust fault detection filter. Then a novel multiple Lyapunov-Krasovskii function is proposed for deriving sufficient existence conditions of the robust fault detection filter based on the average dwell time technique. By introducing slack matrix variable, the coupling between the Lyapunov matrix and system matrix is removed, and the conservatism of results is reduced. Based on the robust fault detection filter, residual is generated and evaluated for detecting faults. In addition, the results of this paper are dependent on time delays,and represented in the form of linear matrix inequalities. Finally,the simulation example verifies the effectiveness of the proposed method.

关键词： switched system average dwell time mixed H-/H∞ robust fault detection filter time-varying delay

Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

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Neural Regeneration Research 2025年第4期20卷 1192-1206页

作者： Tyler A.Smith Liwen Zhou Cameron L.Ghergherehchi Michelle Mikesh Cathy Z.Yang Haley O.Tucker JuliAnne Allgood Jared S.Bushman George D.Bittner department of Molecular Biosciences University of Texas at AustinAustinTXUSA department of Neuroscience University of Texas at AustinAustinTXUSA Division of Pharmaceutical Sciences University of WyomingLaramieWYUSA

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal ***,such peripheral nerve allografts undergo immunological rejection by the host immune *** contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian *** relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this *** hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral *** examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal ***-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host *** to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days *** morphological signs of rejection,such as col

关键词： allograft rejection axotomy macrophage myelin nerve repair polyethylene glycol(PEG) sciatic nerve T cell transplantation Wallerian degeneration

Secure communication based on spatiotemporal chaos

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Chinese Physics B 2015年第8期24卷 233-238页

作者：任海鹏白超 department of Information and control Engineering Xi’an University of Technology

In this paper, we propose a novel approach to secure communication based on spatiotemporal chaos. At the transmitter end, the state variables of the coupled map lattice system are divided into two groups: one is used as the key to encrypt the plaintext in the N-shift encryption function, and the other is used to mix with the output of the N-shift function to further confuse the information to transmit. At the receiver end, the receiver lattices are driven by the received signal to synchronize with the transmitter lattices and an inverse procedure of the encoding is conducted to decode the *** simulation and experiment based on the TI TMS320C6713 Digital Signal Processor(DSP) show the feasibility and the validity of the proposed scheme.

关键词： secure communication spatiotemporal chaos synchronization N-shift function

Driving force and structural strength evaluation of a flexible mechanical system with a hydrostatic skeleton

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第4期11卷 255-262页

作者： Daisuke MARUYAMA Hitoshi KIMURA Michihiko KOSEKI Norio INOU department of Mechanical and control Engineering Tokyo Institute of Technology

The purpose of this study was to build a flexible mechanical system with a hydrostatic *** main components of this system are two type flexible *** is a structural bag with constant inner *** other is an actuator bag with controlled inner *** design the system,it was necessary to estimate both structural deformation and driving *** analysis of flexible bags,however,is difficult because of large nonlinear *** study analyzed structural strength and driving force of flexible bags with the nonlinear finite element analysis (FEA) software *** stress concentration dependency on the bag shape is described and the driving force is calculated to include the large *** the analytical results,this study derives an empirical equation of driving *** validity of the equation was confirmed by condition-changed analyses and experimental results.

关键词： Flexible mechanical system Hydrostatic skeleton Design method Nonlinear finite element analysis (FEA)

A seventh-order model for dynamic response of an electro-hydraulic servo valve

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Chinese Journal of Aeronautics 2014年第6期27卷 1605-1611页

作者： Liu Changhai Jiang Hongzhou department of Fluid control and Automation Harbin Institute of Technology

In this paper, taking two degrees of freedom on the armature–flapper assembly into account, a seventh-order model is deduced and proposed for the dynamic response of a two-stage electro-hydraulic servo valve from nonlinear equations. These deductions are based on fundamental laws of electromagnetism, fluid, and general mechanics. The coefficients of the proposed seventhorder model are derived in terms of servo valve physical parameters and fluid properties *** validating the results of the proposed model, an AMESim simulation model based on physical laws and the existing low-order models validated by other researchers through experiments are used to compare with the seventh-order model. The results show that the seventh-order model can reflect the physical behavior of the servo valve more explicitly than the existing low-order models and it could provide guidance more easily for a linear control design approach and sensitivity analysis than the AMESim simulation model.

关键词： Hydraulic control systems Nozzle–flapper Servo valve Torque motor Transfer function