摘要：The grouted bolt,combining rock bolting with grouting techniques,provides an effective solution for controlling the surrounding rock in deep soft rock and fractured *** has been extensively applied in numerous deep mining areas characterized by soft rock roadways,where it has demonstrated remarkable control *** article systematically explores the evolution of grouted bolting,covering its theoretical foundations,design methods,materials,construction processes,monitoring measures,and methods for assessing its *** overview encompassed several key elements,delving into anchoring theory and grouting reinforcement *** new principle of high pretensioned high-pressure splitting grouted bolting collaborative active control is introduced.A fresh method for dynamic information design is also *** discussion touches on both conventional grouting rock bolts and cable bolts,as well as innovative grouted rock bolts and cables characterized by their high pretension,strength,and sealing hole *** examination of the merits and demerits of standard inorganic and organic grouting materials versus the new inorganic–organic composite materials,including their specific application conditions,was ***,the article presents various methods and instruments to assess the support effect of grouting rock bolts,cable bolts,and grouting ***,it provides a foundation for understanding the factors influencing decisions on grouted bolting timing,the sequence of grouting,the pressure applied,the volume of grout used,and the strategic arrangement of grouted rock bolts and cable *** application of the high pretensioned high-pressure splitting grouted bolting collaborative control technology in a typical kilometer-deep soft rock mine in China—the soft coal seam and soft rock roadway in the Kouzidong coal mine,Huainan coal mining area,was ***,the existing problems in grouted bolting control

摘要：Inflatable space structures may undergo the vibration of a long duration because of their features of dynamic deployment,high flexibility,and low-frequency *** this paper,a topology optimization methodology is proposed to reduce the vibration of a spinning inflatable *** the first step,a variable-length shell element is developed in the framework of arbitrary Lagrange-Euler(ALE)and absolute nodal coordinate formulation(ANCF)to accurately model the deployment dynamics of the inflatable *** the help of two additional material coordinates,the shell element of ALE-ANCF has the ability to describe the large deformation,large overall motion,and variable length of an inflatable *** nonlinear elastic forces and additional inertial forces induced by the variable length are analytically *** the second step,a topology optimization procedure is presented for the dynamic response of an inflatable structure through the integration of the equivalent static loads(ESL)method and the density *** ESL sets of the variable-length inflatable structure are defined to simplify the dynamic topology optimization into a static one,while the density-based topology optimization method is used to describe the topology of the inflatable structure made of two materials and solve the static optimization *** order to obtain more robust optimization results,sensitivity analysis,density filter,and projection techniques are also ***,a benchmark example is presented to validate the ALE-ANCF modeling *** deployment dynamics and corresponding topology optimization of a spinning inflatable structure are studied to show the effectiveness of the proposed topology optimization methodology.

摘要：Coal mine fires,which can cause heavy casualties,environmental damages and a waste of coal resources,have become a worldwide *** at overcoming the drawbacks,such as a low analysis efficiency,poor stability and large monitoring error,of the existing underground coal fire monitoring technology,a novel monitoring system based on non-dispersive infrared(NDIR)spectroscopy is *** this study,first,the measurement principle of NDIR sensor,the gas concentration calculation and its temperature compensation algorithms were ***,taking CO and CH_(4) as examples,the liner correlation coefficients of absorbance and the temperature correction factors of the two indicator gases were calculated,and then the errors of concentration measurement for CO,CO_(2),CH_(4) and C_(2)H_(4) were further *** results disclose that the designed NDIR sensors can satisfy the requirements of industrial standards for monitoring the indicator gases for coal fire *** the established NDIR-based monitoring system,the NDIRbased spectrum analyzer and its auxiliary equipment boast intrinsically safe and explosion-proof performances and can achieve real-time and in-situ detection of indicator gases when installed close to the coal fire risk area ***,a field application of the NDIR-based monitoring system in a coal mine shows that the NDIR-based spectrum analyzer has a permissible difference from the chromatography in measuring the concentrations of various indicator ***,the advantages of high accuracy,quick analysis and excellent security of the NDIR-based monitoring system have promoted its application in many coal mines.

摘要：SRAM(static random access memory)-based FPGA(field programmable gate array), owing to its large capacity, high performance, and dynamical reconfiguration, has become an attractive platform for So PC(system on programmable chip) development. However, as the configuration memory and logic memory of the SRAM-based FPGA are highly susceptible to SEUs(single-event upsets) in deep space, it is a challenge to design and implement a highly reliable FPGA-based system for spacecraft, and no practical architecture has been proposed. In this paper, a new architecture for a reliable and reconfigurable FPGAbased computer in a highly critical GNC(guidance navigation and control) system is proposed. To mitigate the effect of an SEU on the system, multi-layer reconfiguration and multi-layer TMR(triple module redundancy) techniques are proposed, with a reliable reconfigurable real-time operating system(Space OS) managing the system level fault tolerance of the computer in the architecture. The proposed architecture for the reconfigurable FPGA-based computer has been implemented with COTS(commercial off the shelf) FPGA and has firstly been applied to the GNC system of a circumlunar return and reentry flight vehicle. The in-orbit results show that the proposed architecture is capable of meeting the requirements of high reliability and high availability, and can provide the expressive varying functionality and runtime flexibility for an FPGA-based GNC computer in deep space.

摘要：In this paper an adaptive guidance law based on the characteristic model is designed to track a reference drag acceleration for reentry vehicles like the Shuttle. The characteristic modeling method of linear constant systems is extended for single-input and single-output （SlSO） linear time-varying systems so that the characteristic model can be established for reentry vehicles. A new nonlinear differential golden-section adaptive control law is presented. When the coefficients belong to a bounded closed convex set and their rate of change meets some constraints, the uniformly asymptotic stability of the nonlinear differential golden-section adaptive control system is proved. The tracking control law, the nonlinear differential golden-section control law, and the revised logical integral control law are integrated to design an adaptive guidance law based on the characteristic model. This guidance law overcomes the disadvantage of the feedback linearization method which needs the precise model. Simulation results show that the proposed method has better performance of tracking the reference drag acceleration than the feedback linearizaUon one.

摘要：根据沿着重复轴的一种新动态 linearization 技术，双阶段的最佳的反复的学习控制为非线性、非仿射的分离时间的系统被介绍。双阶段显示二个最佳的学习阶段分别地被设计反复地改进控制输入顺序和学习获得。主要特征是控制器设计和集中分析仅仅取决于动态系统的 I/O 数据。换句话说，没有知道系统的任何另外的知识，我们能容易选择控制参数。模拟学习沿着重复轴说明介绍方法的几何集中，在哪个马路的一个例子控制为它的内在的工程重要性是引人注目的交通反复的学习。

摘要：为解决多服务模式的网约车市场中所存在的模式间供需时空不匹配的问题,打破模式间派单壁垒,减少车辆无效巡游,提升乘客体验,提出一种基于强化学习的跨模式派单算法。首先,设计跨模式派单的运行规则和相应的仿真环境为算法的训练提供环境支持。其次,针对派单过程中乘客需求动态变化的特点,设计两阶段派单流程。在第一阶段,根据车辆与需求的时空特征确定虚拟派单请求;在第二阶段,采用k最近邻算法对可行派单请求进行细化,选择与虚拟派单请求最为相似的请求作为最终的派单方案。实验表明,与基线方法相比,所提出的跨模式派单算法提升了基础服务模式中3.1%的请求响应率,同时减少了高级服务模式中车辆的空驶时间,实现了更高的经济效益与服务水平。

摘要：结构拓扑优化在过去的三十年里经历了巨大的发展,充分利用高性能计算资源有助于拓宽拓扑优化在大规模设计问题中的应用。本文提出了一种针对一般三维拓扑优化的基于子区域的并行策略。通过子区域划分、矩阵运算、引入单元硬杀算法,优化过程得以显著提速.将该策略整合进高效、简洁的Python代码;该代码可适用于任意形状的设计域.附录一中给出的完整代码,易于扩展,扩展后可解决多类优化问题.通过求解四个柔度最小化问题展示了该策略的高效性.本研究在机械工程、先进制造,以及建筑设计等领域有潜在的应用价值.

摘要：Single gimbal control moment gyroscope(SGCMG)with high precision and fast response is an important attitude control system for high precision docking,rapid maneuvering navigation and guidance system in the aerospace *** this paper,considering the influence of multi-source disturbance,a data-based feedback relearning(FR)algorithm is designed for the robust control of SGCMG gimbal servo *** on adaptive dynamic programming and least-square principle,the FR algorithm is used to obtain the servo control strategy by collecting the online operation data of SGCMG *** is a model-free learning strategy in which no prior knowledge of the SGCMG model is ***,combining the reinforcement learning mechanism,the servo control strategy is interacted with system dynamic of *** adaptive evaluation and improvement of servo control strategy against the multi-source disturbance are ***,a data redistribution method based on experience replay is designed to reduce data correlation to improve algorithm stability and data utilization ***,by comparing with other methods on the simulation model of SGCMG,the effectiveness of the proposed servo control strategy is verified.

摘要：Axial compression tests were conducted on AZ31 B magnesium and A6063 aluminum thin-walled square tubes with varied lengths and induced features at different compression rates. In compression, the magnesium tubes exhibited a "local buckling and fracture" mode, with three fracture patterns, i.e."horizontal","double-oblique", and "spiral" fractures. In general, the magnesium tube showed an inferior crashworthiness to the aluminum square tube. In addition, the effects of L/W ratio, strain rate and induced features on the crashworthiness of thin-walled square tubes were investigated. With an increase in the L/W ratio(L and W represent the tube length and width, respectively) from 1 to 4, the maximal force and global specific energy absorption decreased in a power-law trend for the magnesium tubes,while they remained approximately constant for the aluminum tubes. Furthermore, as the compression rate increased from 5×10-5 to 10 m/s, the primary crashworthiness parameters of the magnesium tubes increased in an approximately exponential manner,while for the aluminum tubes,they changed slightly. Finally,the involved induced features were proven to be not an effective method to improve the specific energy absorption of magnesium tubes, thus, more trigger types,locations,and sizes will be evaluated in future to improve the energy-absorption ability.