Distributed active vibration control for helicopter based on diffusion collaboration

The active vibration control technology has been successfully applied to several helicopter types.However,with the increasing of control scale,traditional centralized control algorithms are experiencing significant increase of computational complexity and physical implementation challenging.To address this issue,a diffusion collaboration-based distributed Filtered-x Least Mean Square algorithm applied to active vibration control is proposed,drawing inspiration from the concept of data fusion in wireless sensor network.This algorithm distributes the computation load to each node,and constructs the active vibration control network topology of large-scale system by discarding the weak coupling secondary paths between nodes,achieving distributed active vibration control.In order to thoroughly validate the effectiveness and superiority of this algorithm,a helicopter fuselage model is designed as the research object.Firstly,the excellent vibration reduction performance of the proposed algorithm is confirmed through simulations.Subsequently,specialized node control units are developed,which utilize STM32 microcontroller as the processing unit.Further,a distributed control system is constructed based on multi-processor collaboration.Building on this foundation,a large-scale active vibration control experimental platform is established.Based on the platform,experiments are carried out,involving the 4-input 4-output system and the 8-input 8-output system.The experimental results demonstrate that under steady-state harmonic excitation,the proposed algorithm not only ensures control effectiveness but also reduces computational complexity by 50%,exhibiting faster convergence speed compared with traditional centralized algorithms.Under time-varying external excitation,the proposed algorithm demonstrates rapid tracking of vibration changes,with vibration amplitudes at all controlled points declining by over 94%,proving the strong robustness and adaptive capability of the algorithm.

Ectopic Expression of TRIM25 Restores RIG-I Expression and IFN Production Reduced by Multiple Enteroviruses 3Cpro

Enteroviruses(EVs) 3C proteins suppress type I interferon(IFN) responses mediated by retinoid acid-inducible gene I(RIG-I), while an E3 ubiquitin ligase, tripartite motif protein 25(TRIM25)-mediated RIG-I ubiquitination is essential for RIG-I antiviral activity. Therefore, whether the effect of EVs 3C on RIG-I is associated with TRIM25 expression is worth to be further investigated. Here, we demonstrate that 3C proteins of EV71 and coxsackievirus B3(CVB3) reduced not only RIG-I expression but also TRIM25 expression through protease cleavage activity, while overexpression of TRIM25 restored RIG-I expression and IFN-b production reduced by 3C proteins. Further investigation confirmed that the two amino acids and functional domains in TRIM25 required for RIG-I ubiquitination and TRIM25 structural conformation were essential for the recovery of RIG-I expression. Moreover, we also observed that TRIM25 could rescue RIG-I expression reduced by 3C proteins of CVA6 and EV-D68 but not CVA16. Our findings provide an insightful interpretation of 3C-mediated host innate immune suppression and support TRIM25 as an attractive target against multiple EVs infection.

Waste cotton fabric derived porous carbon containing Fe_(3)O_(4)/NiS nanoparticles for electrocatalytic oxygen evolution

Developing low-cost,active and durable electrocatalysts for oxygen evolution reaction(OER)is an urgent task for the applications such as water splitting and rechargeable metal-air battery.Herein,this work reports the fabrication of a metal and hetero atom co-doped fibrous carbon structure derived from cotton textile wastes and its use as an efficient OER catalyst.The free-standing fibrous carbon structure,fabricated with a simple two-step carbonization process,has a high specific surface area of 1796 m^2/g and a uniform distribution of Fe_(3)O_(4)/NiS nanoparticles(Fe_(3)O_(4)/NiS@CC).The composite exhibits excellent OER performance with an onset potential of 1.44 V and a low overpotential of 310 mV at the current density of 10 mA/cm^2in a 1.0 M KOH solution,which even surpass commercial Ru O_(2)catalyst.Additionally,this ternary catalyst shows remarkable long-term stability without current density loss after continuous operation for 26 h.It can be believed that the outstanding OER performance is attributed to the synergistic effect between the iron oxides and nickel sulphides,as well as the micro-meso porous carbon structure.This study demonstrates a new strategy to use conventional textile materials to prepare highly efficient electrocatalysts;it also provides a simple approach to turn textile waste into valuable products.