摘要：A direct drive actuator （DDA） with direct drive valves （DDVs） as the control device is an ideal solution for a flight actuation system. This paper presents a novel triple-redundant voice coil motor （TRVCM） used for redundant DDVs. The TRVCM features electrical/mechanical hybrid triple-redundancy by securing three stators along with three moving coils in the same frame. A permanent magnet （PM） Halbach array is employed in each redundant VCM to simplify the system structure. A back-to-back design between neighborly redundancies is adopted to decouple the magnetic flux linkage. The particle swarm optimization （PSO） method is implemented to optimize design parameters based on the analytical magnetic circuit model. The optimization objective function is defined as the acceleration capacity of the motor to achieve high dynamic performance. The optimal geometric parameters are verified with 3D magnetic field finite element analysis （FEA）. A research prototype has been developed for experimental purpose. The experimental results of magnetic field density and force output show that the proposed TRVCM has great potential of applications in DDA systems.

摘要：This paper proposes a new optimization method to improve the performance of a null convention logic asynchronous *** combinational logic modules in the pipelines can work alternately in null and data cycles by using a parallel processing *** complete waiting time for both null and data signals of combinational logic output in previous asynchronous register stage is reduced by decoupling the output from combinational logic *** penalty brought by null cycle is reduced while the data processing capacity is *** novel asynchronous pipeline based on asynchronous full adders with different bit widths as asynchronous combination logic modules is simulated using 0.18-μm CMOS *** on 6 bits asynchronous adder as asynchronous combination logic modules, the simulation result of this new pipeline proposal demonstrates a high throughput up to 72.4% improvement with appropriate power *** indicates the new design proposal is preferable for high-speed as ynchronous designs due to its high throughput and delay-insensitivity.

摘要：This paper intends to provide theoretical basis for matching design of hydraulic load simulator （HLS） with aerocraft actuator in hardware-in-loop test, which is expected to help actuator designers overcome the obstacles in putting forward appropriate requirements of HLS. Traditional research overemphasizes the optimization of parameters and methods for HLS controllers. It lacks deliberation because experimental results and project experiences indicate different ultimate performance of a specific HLS. When the actuator paired with this HLS is replaced, the dynamic response and tracing precision of this HLS also change, and sometimes the whole system goes so far as to lose control. Based on the influence analysis of the preceding phenomena, a theory about matching design of aerocraft actuator with HLS is presented, together with two paired new concepts of ＂Standard Actuator＂ and ＂Standard HLS＂. Further research leads to seven important conclusions of matching design, which suggest that appropriate stiffness and output torque of HLS should be carefully designed and chosen for an actuator. Simulation results strongly support that the proposed principle of matching design can be anticipated to be one of the design criteria for HLS, and successfully used to explain experimental phenomena and project experiences.

摘要：A large number of cases show that the multi-objective optimization method can significantly improve building *** method for multi-objective building performance optimization(BPO)design has achieved rapid development in recent ***,the BPO method still needs to be ***,weak interaction between the optimization process and the decision-making process results in low optimization efficiency,which limits the widespread application of the optimization method in early design *** this paper,a new interactive BPO mode is explored to strengthen the interaction between the optimization process and decisionmaking process,and a preference-based multi-objective BPO method is proposed to account for designers'decision preferences during the optimization process,making the objective more controllable,improving the optimization efficiency and ensuring the diversity of ***,this paper illustrates the proposed method in detail,defines the concept of performance preference,expounds the flow of the preference-based multi-objective optimization algorithm,and proposes three indicators to evaluate the algorithm,which includes convergence speed,preference satisfaction rate,and diversity ***,through testing and comparison,it is found that the proposed preference-based algorithm has advantages over the non-preference optimization algorithm(represented by the NSGA-II algorithm).The proposed method leads to faster convergence and higher preference satisfaction,so it is more suitable for the BPO process in the early design ***,the proposed method can achieve 100%preference satisfaction rate with only 2400 simulations,while the non-preference method can only achieve 20%preference satisfaction rate after 5800 *** this paper,a preference-based multi-objective BPO method is proposed to make the optimization process closely interact with the decision-making process and make the design preferences be accoun

摘要：In the design optimization of variable stiffness composites,manufacturing constraints imposed by the automated fiber placement technology must be *** the present paper,two filters are proposed to address this issue,and they are incorporated into the Shepard interpolation-based design optimization framework developed in our previous *** fiber angle arrangement of a composite is represented by a continuous function that interpolates fiber angles at scattered design *** filters are appointed for each design point to deal with two typical manufacturing constraints,i.e.,fiber curvature and gap/*** each design point,the sensitivity is first filtered in a rectangular region around this point,and by this means the fiber curvature is controlled;then in another rectangular region around this design point,the filtered sensitivities are averaged,and the result is used to update the corresponding design *** numerical examples are investigated,and the results show that the proposed method is effective.

摘要：The influence of the dispersion and uncertainty of the dynamic shear wave velocity and Poisson＇s ratio of soil in a hard rock site was investigated on the seismic response of reactor building structure. The analysis is performed by considering the soil-structure interaction effects and based on the model of the reactor building in a typical pressurized water reactor nuclear power plant （NPP）. The numerical results show that for the typical floor selected, while the relative increment ratio of the dynamic shear wave velocity varies from -30% to 30% compared to the basis of 1 930 m/s, the relative variation of the horizontal response spectra peak value lies in the scope of ±10% for the internal structure, and the relative variation of the frequency corresponding to the spectra peak is 0.0% in most cases. The relative variation of the vertical response spectra peak value lies in the scope of - 10% to 22%, and the relative variation of the frequency corresponding to the Spectra peak lies in the scope of - 22% to 4%. The analysis indicates that the dynamic shear wave velocity and the Poisson＇s ratio of the rock would affect the seismic response of structure and the soil-structure interaction effects should be considered in seismic analysis and design of NPP even for a hard rock site.

摘要：We have investigated the distribution of the electric field in p-i-n GaN avalanche photodiodes under different reverse bias values. type and separate absorption and multiplication （SAM） type We have also analyzed the influences of the parameters of each layer, including width and concentration, on the distribution of the electric field, especially on the breakdown voltage. It is found that a relatively high concentration of p-GaN （higher than 1×10^18 cm-3） and low cartier concentration of i-GaN （lower than 5×1016 cm-3） are helpful to restrict the electric field and reduce the breakdown voltage. In a SAM （p-i-n-i-n） structure, a suitable choice should be made for the concentration and thickness of the intermediate n-GaN layer in order to decrease breakdown voltage and prevent the device from degenerating into a p-i-n structure. Finally, the optimized material parameters of each layer are proposed.

摘要：In this paper, we study an energy efficient multi-antenna unmanned aerial vehicle(UAV)-enabled half-duplex mobile relaying system under Rician fading channels. By assuming that the UAV follows a circular trajectory at fixed altitude and applying the decode-and-forward relaying strategy, we maximize the energy efficiency by jointly designing beamforming, power allocation, circular radius and flight speed, subject to the sum transmit power constraint on source node and UAV relay node. First, we maximize the end-to-end signal-to-noise ratio by jointly designing beamforming and statistical power allocation. Based on the obtained beamforming and power allocation results, we then obtain a semi closed-form expression of energy efficiency, and finally maximize energy efficiency by optimizing flight speed and circular radius, allowing optimal circular radius to be obtained via numerical computation. Numerical results demonstrate that the proposed scheme can effectively enhance the system energy efficiency.

摘要：A stepped-section ring consists of two rectangular section rings,a big ring and a small ring,joined *** kind of ring is difficult to process by the ring rolling technique because of its complex cross-sectional *** a reasonable blank design is *** this paper,four blank designs,one is a rectangular cross-section and the other three are stepped-sections with different step volumes,are proposed and compared with each other using theoretical analysis,FE simulation and *** is shown that three of the designs can lead to volume flow from small ring into big ring during rolling,which is disadvantageous for shape formation and dimensional precision;however,the other design may result in good ring shape and high dimensional ***,the optimal blank design is determined to be the one in which the volumes of the big and small rings of the initial blank are equal to those of the final rings,respectively.

摘要：The 60-GHz traveling-wave tube （TWT） prevails nowadays as the amplifier for the satellite communication and electronic countermeasures. The folded waveguide （FW） is a promising all-metal slow-wave structure （SWS） for the 60-GHz TWT with advantages of robust performance, fine heat dissipation, considerable power and bandwidth. A novel FW periodically loaded with rectangular grooves is analyzed for the purpose of gaining higher power and gain. The rf characteristics are investigated by numerical simulation, and the nonlinear large- signal performance of such a TWT is analyzed by a 3I） particle-in-cell code MAGIC. Compared with normal circuits, relatively higher continuous-wave power （40-56 W） and similar bandwidth （5 GHz） are predicted by simulation. Meanwhile, the designed operation voltage is 10.5 kV, which keeps the low-voltage advantage of the popular helix TWT competitor. The novel FW will favor the design of a broadband and high-power 60-GHz TWT