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The TianQin Project is aiming at gravitational wave (GW) detection in space. TianQin GW observatory comprises three satellites orbiting on 1 × 105 km Earth orbits to form an equilateral-triangle constellation. In order to minimize the variations in arm lengths and breathing angles, the satellites must be launched and adjusted precisely into an optimized orbit. Therefore, satellite laser ranging must be used to enhance the precision of satellite orbit determination. To develop the capability of satellite laser ranging for TianQin’s orbit, the TianQin Laser Ranging Station has been designed and constructed to perform high-precision laser ranging for TianQin satellites and lunar laser ranging as well. Applying a 1064 nm Nd: YAG laser with 100 Hz repetition frequency, 80 pico-second pulse duration, and 2 × 2 array of superconducting nanowire single-photon detectors, we have obtained the laser echo signals from the five lunar retro-reflector arrays, and the measurement data have been packaged into 234 normal points (NPs), including a few data measured during the full-moon lunar phase. Each NP is calculated from continuous measurement for about ten minutes and the statistical error of the NPs is about 7 mm (1σ).

This paper introduces a kind of intelligent mobile electric vehicle charging robot design scheme. The charging robot is used in the parking lot of the residential area and will automatically charge several electric cars at night. The robot system adopts the preset tracking positioning principle and realizes the accurate positioning of parking spaces at a low cost. The robot system adopts the method of unified deployment of charging socket, which solves the problem of different charging port locations and interface standards for different brands of vehicles. The charging robot can automatically open the charging port sealing cover and protect the vehicle from damage. This solution not only solves the problem of automatic charging of multiple electric vehicles,it is also very important to reduce the distribution system of the parking lot. At the same time, it has positive significance for state Grid to carry out the ladder electricity price policy of time-sharing pricing.

Many pathogenic fungi depend on the development of specialized infection structures called appressoria to invade their hosts and cause disease. Impairing the function of fungal infection structures therefore provides a potential means by which diseases could be prevented. In spite of this extraordinary potential, however, relatively few anti-penetrant drugs have been developed to control fungal diseases, of either plants or animals. In the present study, we report the identification of compounds that act specifically to prevent fungal infection. We found that the organization of septin GTPases, which are essential for appressorium-mediated infection in the rice blast fungus Magnaporthe oryzae, requires very-long-chain fatty acids (VLCFAs), which act as mediators of septin organization at membrane interfaces. VLCFAs promote septin recruitment to curved plasma membranes and depletion of VLCFAs prevents septin assembly and host penetration by M. oryzae. We observed that VLCFA biosynthesis inhibitors not only prevent rice blast disease, but also show effective, broad-spectrum fungicidal activity against a wide range of fungal pathogens of maize, wheat and locusts, without affecting their respective hosts. Our findings reveal a mechanism underlying septin-mediated infection structure formation in fungi and provide a class of fungicides to control diverse diseases of plants and animals.

Simple Summary Intestinal microbiota play crucial roles for their hosts. Odontolabis fallaciosa shows striking sexual dimorphism and male trimorphism, which represents an interesting system to study their gut microbiota. We have compared the intestinal bacterial community structure between the two sexes and among three male morphs of O. fallaciosa. The gut bacterial community structure was significantly different between males and females. The females were associated with higher bacterial alpha-diversity relative to males. Large males had a higher relative abundance of Firmicutes and Firmicutes/Bacteroides (F/B) ratio, which contributed to nutritional efficiency. The results increased our understanding of beetle–bacterial interactions of O. fallaciosa between the two sexes, and among three male morphs, which might reveal the relationship among the gut microbiota, nutrition level, and phenotypic evolution of the stag beetle. Abstract Odontolabis fallaciosa (Coleoptera: Lucanidae) is a giant and popular stag beetle with striking sexual dimorphism and male trimorphism. However, little is known about their intestinal microbiota, which might play an indispensable role in shaping the health of their hosts. The aim of this study was to investigate the intestinal bacterial community structure between the two sexes and among three male morphs of O. fallaciosa from China using high-throughput sequencing (Illumina MiSeq). The gut bacterial community structure was significantly different between males and females, suggesting that sex appeared to be the crucial factor shaping the intestinal bacterial community. Females had higher bacterial alpha-diversity than males. There was little difference in gut bacterial community structure among the three male morphs. However, compared to medium and small males, large individuals were associated with the higher relative abundance of Firmicutes and Firmicutes/Bacteroides (F/B) ratio, which might contribute to nutritional efficiency. Overall, these results might help to further our understanding of beetle–bacterial interactions of O. fallaciosa between the two sexes, and among the three male morphs.

For large ground-based telescopes, static and dynamic disturbances would greatly degrade the optical performance. This is especially true for wide field survey telescopes with prime focus optics. The estimation of disturbance effects on large telescopes is becoming increasingly important during the design phase. Therefore, a wide field survey telescope with 2.5 m aperture and 3.5 deg field of view is studied in this research. This telescope is under construction now, and its first light is expected at the beginning of 2023. The estimation method for the optical performance under static and dynamic disturbances in the temporal domain and the active compensation method to improve the optical alignment, are investigated, which is a supplement for the simulation in the frequency domain. First, based on the mechanical model, the optical misalignment is established, where the deviation of the primary mirror is obtained from the length gauges and the deviation of the corrector is computed using the fitting method. Second, a method for compensating the static and dynamic disturbances is proposed, improving the optical performance. This method uses the disturbed primary mirror as the reference, and the corrector is actively controlled to align with it. Finally, a series of experimental tests and numerical simulations is conducted. The results show that the mechanical modeling error is within 10% and the maximum optical misalignment is reduced from 12 ′ ′ / 0.27 to 0.2 ′ ′ / 0.006 m m for static disturbance and from 1.3 ′ ′ / 0.03 to 0.4 ′ ′ / 0.01 m m for dynamic disturbance. Through active compensation, the telescope optical property is greatly improved. The modeling method and the simulation process mentioned in this research can also be used in the other relevant fields.

This paper presents an efficient method that overcomes the problem of the control design of the post-stall maneuver under unsteady aerodynamics. On the basis of adequate data of the large amplitude oscillation experiment device in wind tunnel test, the unsteady aerodynamics model with nonlinearity, coupling and hysteresis is established by the improved Extreme Learning Machine (ELM) method. Considering the nonlinearity of the longitudinal model of the advanced fighter and the aerodynamics characteristics of the post-stall maneuver, the control law under large attack angle is designed combining the backstepping method and the daisy chain allocation method. The first order filter is adopted to prevent the “differential explosion” problem. The designed control allocation law guarantees that the conventional surfaces and the vector nozzle deflect coordinately within the position limits and the rate limits. The Radial Basis Function (RBF) network is applied to model the uncertainty, and the stability of the proposed control law which considering the uncertainty is also proved. Digital simulations of the typical “Cobra” maneuver under the unsteady aerodynamics are completed with comparisons under different conditions. Simulations results verify the validity of the proposed control law under unsteady aerodynamics and the aerodynamics uncertainty.

The circular-arch flexible structure is widely used in various fields, especially the support structure of the optical mirrors. This paper aims to present a generalized formulation of the circular-arch flexible structure and a continuous method to optimize this flexible structure considering the material selection and geometry simultaneously. First, an analytical model based on the variational principle is derived for calculating the radial and tangential stiffness of the flexible element, and then the generalized formulation of the integral flexible structure is obtained by considering force equilibrium and compatible deformation. Second, the structural optimization is implemented by combining the material selection and geometrical parameters, where the continuous artificial variables are used to represent the selected material. Finally, the experimental and numerical examples are given to verify the analytical formulation and the optimization scheme. The experimental and FE simulation results of the flexible element and the integral flexible structure indicate that the presented mechanical model is capable of capturing the linear behavior. For the geometrical nonlinear deformation, there exist some errors. And the optimization results demonstrate that the presented scheme is able to obtain the discrete material design and the optimal geometry.

This paper presents an innovative unsteady aerodynamic modeling method based on the improved Extreme Learning Machine (ELM), which is further successfully applied into the biaxial coupled oscillation during the post stall maneuver flight. The underlying data of pitch-roll and yaw-roll coupled oscillation for the aircraft, which simulate the post stall maneuver such as Herbst maneuver and barrel roll, are obtained by the wind tunnel test equipment and then separated as training samples and testing samples. To reduce the prediction error, the cross validation method is employed. And the parameters including the connect weights between the input layer and the hidden layer, the bias and the number of the neurons in the hidden layer are selected based on the testing samples. According to the verifying samples, the comparison is accomplished among the back-propagation neural network (BPNN) method, the enhanced incremental ELM (EI-ELM) method and the improved ELM method. The simulation results demonstrate that the improved ELM method has characteristics of high precision, strong versatility and fast prediction in the unsteady aerodynamic modeling.

Odontolabis fallaciosa (Coleoptera: Lucanidae) is a giant and popular stag beetle with striking sexual dimorphism and male trimorphism. However, little is known about their intestinal microbiota, which might play an indispensable role in shaping the health of their hosts. The aim of this study was to investigate the intestinal bacterial community structure between the two sexes and among three male morphs of O. fallaciosa from China using high-throughput sequencing (Illumina MiSeq). The gut bacterial community structure was significantly different between males and females, suggesting that sex appeared to be the crucial factor shaping the intestinal bacterial community. Females had higher bacterial alpha-diversity than males. There was little difference in gut bacterial community structure among the three male morphs. However, compared to medium and small males, large individuals were associated with the higher relative abundance of Firmicutes and Firmicutes/Bacteroides (F/B) ratio, which might contribute to nutritional efficiency. Overall, these results might help to further our understanding of beetle&ndash, bacterial interactions of O. fallaciosa between the two sexes, and among the three male morphs.

A design for a truss mechanism of a secondary mirror based on robotics is proposed. This design would allow for the construction of larger vehicle-mobile telescopes. As the new truss mechanism combines the original support structure and adjustment mechanism, the problems in designing new structures needs to be overcome. In this paper, the basic form of the truss mechanism is determined by finite element method, and the number of limbs meeting the requirements of resonance frequencies and stiffness is obtained. Degrees-of-freedom of the new truss mechanism is calculated by motion space based on geometry algebra and screw theory, It can provide more accurate and specific results compared with the G-K formula. The optimal structure is calculated to meet the requirement in degrees-of-freedom with the minimum possible limbs and kinematic pairs. After the form and the value of joints are determined, the deformations are calculated by stiffness evaluation index. Wavefront aberrations simulated with Zernike polynomials are used to verify the structure.

We propose a new secondary mirror support structure assisted by multi-robotics to improve the observation performance of vehicle-mobile telescope systems. A mathematical model of the displacement at the end of the robotic and the variation of telescope pitch angle is established, then the posture of the robotic is optimized by the Jacobian matrix iteration inverse kinematic problem method. Based on the new support structure, a high-order sensitivity matrix is proposed to establish the mapping relationship between the robotic misalignment and the Zernike coefficient, with the accuracy verified via the Monte Carlo method. The method of adjusting the secondary mirror to compensate the aberration caused by the primary mirror is proposed, and the relationship between the primary mirror surface error and the system error is established under different pitch angles before and after compensation. The experiment and simulation results showed that the adjustment calculated by the high-order sensitivity matrix method can effectively compensate for the misalignment caused by the robotics and the primary mirror surface error to a certain degree. After multiple iterations, the root mean square of the wavefront aberration was better than &lambda, /15. This conclusion provides an engineering application reference value for the secondary mirror support and aberration correction technology of the vehicle telescope system.

This paper presents a precise unsteady aerodynamic modeling method of biaxial coupling oscillation which overcomes the drawbacks of the nonlinearity, coupling and hysteresis of the aerodynamic during post-stall maneuver. In order to establish a large number of experimental data model rapidly, a method of unsteady aerodynamic modeling on the basis of Sequential Minimal Optimization - Support Vector Regression (SMO-SVR) is proposed. The input variables, output variables and kernel functions of the SVR model for unsteady aerodynamic modeling are determined relying on the analysis of the wind tunnel test data. To improve the modeling accuracy, Cross Validation (CV) is successfully applied to adjust the parameters of the proposed SMO algorithm. The accurate unsteady aerodynamic model can be obtained from the random training data and the random testing data. The unsteady aerodynamic modeling under the pitch-roll and the yaw-roll oscillation is completed. Comparing with the Back Propagation Neural Networks (BPNN) method, the method proposed in this paper has characteristics of high accuracy and strong versatility.

This article presents a finite element formulation for static shape control and optimal design of smart reflector with distributed piezoelectric actuators. The finite element model is developed based on the higher-order shear deformation theory where the displacement field in the model accounts for a parabolic distribution of the shear strain, and the shear correction factor is not involved. The Hamilton variational principle is used to formulate the governing equation of the system. A four-node element with seven mechanical degrees of freedom for each node and one electrical potential degree of freedom for each piezoelectric actuator element is used in the finite element formulation. The optimization model for finding the optimal control voltages is derived, and the control voltages can be determined using Lagrange multipliers. The optimal design of actuator locations using simulated annealing algorithm is also investigated. Finally, numerical examples are given to demonstrate the effectiveness of the present model and optimization scheme. The obtained results show that the use of piezoelectric actuators for static shape control of smart reflector can greatly improve the root mean square error, and the optimal location of actuators can be determined effectively using simulated annealing algorithm.

The systematics of Dorcus MacLeay has been a long-standing debate. Mitochondrial genomes were widely used to deeply understand the phylogeny of problematic taxa in virtue of their genetic importance and comprehensiveness. To provide more useful genetic data for resolving the systematic disputation of Dorcus stag beetles. The complete mitochondrial genomes of Dorcus hopei and Dorcus seguyi were obtained using the next generation sequencing. Characteristics of the two genomes are explicated through comparing their genome organization and base composition, protein-coding genes and codon usage, intergenic spacers and non-coding region, transfer and ribosomal RNA genes and control region. Phylogenetic relationships were reconstructed using Maximum likelihood and Bayesian inference analyses based on the concatenated nucleotide sequences of 13 PCGs from 9 stag beetles and 3 scarab beetles. The complete mitogenomes of D. hopei and D. seguyi was 16,026 bp/17,955 bp long, respectively. A tandem repeat with the length of 940 bp was presented in the A+T-rich region in D. hopei. An unexpected non-coding region of 332 bp was located between nad2 and trnW in D. seguyi. The phylogenetic analyses robustly supported that D. hopei formed a branch with the generic type of D. parallelipipedus. Whereas D. seguyi was not covered in the branch of (D. hopei + D. parallelipipedus), but was sister to them. The results indicated that D. hopei should be a good member of Dorcus MacLeay. The taxonomic status of D. seguyi remained to be studied furtherly.

Active shape adjustment of cable net structures is becoming significant when large-size cable net structures are widely applied in various fields, especially in satellite antennas. The main objective of this paper is three-fold. First, the finite element model of cable net structure with active cables is established. The active cable is constructed by incorporating a PZT actuator into flexible cables. Second, based on the finite element model, the shape adjustment method is proposed to find the optimal actuation voltages for the desired shape. The adjustment models include an analytical solution without constraints and two optimization models with constraints which are evaluated by the quadratic criterion and minmax scheme respectively. Finally, the numerical examples of the flexible cable net structure widely applied to the parabolic reflectors of space antennas have been analyzed. It is found that the quadratic criterion performs better than the minmax scheme for solving shape adjustment problem of cable net structures, and the surface accuracy of the cable net structure with active cables can be well improved by PZT actuators.

The clearance in joints influences the dynamic stability and the performance of deployable space structures (DSS). A virtual experimental modal analysis (VEMA) method is proposed to deal with the effects of joint clearance and link flexibility on the dynamic characteristics of the DSS in this paper. The focus is on the finite element modeling of the clearance joint, VEMA and the modal parameters identification of the DSS. The finite element models (FEM) of the clearance joint and the deployable structure are established in ANSYS. The transient dynamic analysis is conducted to provide the time history data of excitation and response for the VEMA. The fast Fourier transform (FFT) technique is used to transform the data from time domain to frequency domain. The frequency response function is calculated to identify the modal parameters of the deployable structure. Experimental verification is provided to indicate the VEMA method is both a cost and time efficient approach to obtain the dynamic characteristics of the DSS. Finally, we analyze the effects of clearance size and gravity on the dynamic characteristics of the DSS. The analysis results indicate that the joint clearance and gravity strongly influence the dynamic characteristics of the DSS.

In order to solve a class of hypersonic vehicle nonlinear multi-input and multi-output (MIMO) systems control problem, a new kind of adaptive controller is designed in this paper. Backstepping is used to build the control law. To ensure the stability of each uncertain subsystem in each step, a virtual zero-order controller is given in sliding surface design, which can guarantee the robustness. A second-order filter is utilized to replace virtual input to avoid the huge computation complexity in multi-step derivatives. The effectiveness of the control law is verified by simulation even under deep uncertainty. The results suggest the feasibility of this method.