摘要：静电扭转微镜广泛应用于微米光开关、光衰减器、光学扫描仪和光学显示器等领域.过去微镜镜面主要沿单轴或双轴方向偏转,从而限制了入镜光线的反射范围.本文通过建立圆形静电驱动微镜的动力学模型,设计了一种可任意方向偏转的准晶微镜驱动器.然后基于应变梯度理论进行数值求解,分析了其静态和动态现象以及吸合失稳特性,并比较了反射镜面在三种偏转方向下的结果.研究表明,镜面沿着不同方向偏转的结果存在显薯差异.当沿斜轴的偏转角度达到45°时,吸合失稳电压值最小.失稳电压还随着准晶的声子场-相位子场耦合弹性模量和相位子场弹性模量的增加而增加.准晶的介电常数、应变梯度参数和空气阻尼都会影响到徼镜动态系统的扭转.此外,微镜表面分布力的减小也会导致更大的吸合失稳电压.

摘要：在隧道项目中,隧道掘进机(TBM)能否顺利施工取决于TBM系统所有部件(从刀具到后备系统)能否正常运转,并取决于全部机车车辆的配合。而在整个TBM系统中,刀盘是影响TBM施工效率最为关键的因素。刀盘的设计影响到掘削效率、刀盘平衡、刀具使用寿命、主轴承/齿轮箱维护、出渣效果、面刀和边刀/排渣铲斗的磨损情况。总体来说,刀盘设计对掘进速度(ROP)、机器利用率(U)及每日进尺(AR)有重要影响。尽管当前可用文献中已就盘形滚刀、切削力、刀盘的某些设计特征做了讨论,但与本论题相关的文献却十分有限,这是因为刀盘的设计主要由隧道掘进机制造商负责,大部分设计工艺都属制造商专有,虽然本论题当前大受关注,但岩石隧道掘进机的设计对终端客户而言仍是个谜题。本文将试着阐明设计中的基本概念,虽不足以帮助读者进行成熟设计,却可助工程师与承包商理解设计步骤中的构思过程、合理设计中应注意的事项以及刀盘设计对于隧道掘进机运行及寿命周期的意义。

摘要：集矿机与深海沉积物之间的粘附会显著影响集矿机在深海环境中的行走性能,当在进行集矿机与深海沉积物相互作用仿真时,颗粒相互作用参数选用的准确度将会直接影响仿真结果。本文提出一种通过实验与模拟相结合的方法来系统地标定深海沉积物与集矿机之间相互作用参数的方法,进行了单轴压缩试验和宏观粘附试验以及相应的离散元数值模拟,通过修改接触参数直到模拟的结果接近试验结果,然后根据试验结果对JKR粘附接触模型的微观接触参数进行回校,实现了土颗粒-土颗粒、土颗粒-金属之间的接触参数的标定。另外粘附试验表明,在相同表面粗糙度下,测得的附着力顺序5052<316L<STi80<TA2<TC4,这表明铝合金5052的抗粘附性能最好。通过DEM模拟,研究了表面粘附力与微观接触参数之间的关系。结果表明:粘附力与静摩擦系数、滚动摩擦系数关系不大,其主要受恢复系数和表面能的影响,且随着恢复系数的增大而减小,随着表面能的增大而增大。所获得的土壤颗粒对土壤颗粒和土壤颗粒对金属的粘附影响参数,有助于集矿机履齿的设计优化,以降低表面粘附,提高其可移动性和采矿效率。

摘要：In recent few years, significant improvement has been made in developing largescale 3 D printer to accommodate the need of industrial-scale 3 D printing. Cementitious materials that are compatible with 3 D printing promote rapid application of this innovative technique in the construction field with advantages of cost effective, high efficiency, design flexibility and environmental friendly. This paper firstly reviews existing 3 D printing techniques that are currently being used in commercial3 D printers. It then summarizes three latest development of largescale 3 D printing systems and identifies their relationships and limiting factors. Thereafter, critical factors that are used to evaluate the workability and printable performance of cementitious materials are specified. Easy-extrusive, easy-flowing, well-buildable, and proper setting time are significant for cementitious material to meet the critical requirements of a freeform construction process. Finally, main advantages, potential applications and the prospects of future research of 3 D printing in construction technology are suggested. The objective of this work is to review current design methodologies and operational constraints of largescale 3 D printing system and provide references for optimizing the performance of cementitious material and promote its responsible use with largescale 3 D printing technology.

摘要：engineering designs for mountainous highways emphasize compliance checking to ensure safety. However, relying solely on compliance checking may lead designers to minimize costs at the expense of high risk indicators, since the overall risk level of the highway design is unknown to the designers. This paper describes a method for the simultaneous consideration of traffic safety risks and the associated cost burden related to the appropriate planning and design of a mountainous highway. The method can be carried out in four steps: First, the highway design is represented by a new parametric framework to extract the key design variables that affect not only the life-cycle cost but also the operational safety. Second, the relationship between the life-cycle cost and the operational safety risk factors is established in the cost-estimation functions. Third, a fault tree analysis (FTA) is introduced to identify the traffic risk factors from the design variables. The safety performance of the design solutions is also assessed by the generalized linear-regression model. Fourth, a theory of acceptable risk analysis is introduced to the traffic safety assessment, and a computing algorithm is proposed to solve for a cost-efficient optimal solution within the range of acceptable risk, in order to help decision-makers. This approach was applied and examined in the Sichuan–Tibet Highway engineering project, which is located in a complex area with a large elevation gradient and a wide range of mountains. The experimental results show that the proposed approach significantly improved both the safety and cost performance of the project in the study area.

摘要：梁、板和壳作为基本力学结构在微机电系统和纳机电系统中广泛用作传感器、驱动器、能量俘获器等。深入理解这些电介质结构的力电耦合有助于微纳机电系统中结构的设计、制备和优化。本文中,我们阐述了曲电圆板的力电耦合行为,其中通过引入应变梯度将经典力电耦合理论拓宽到中心对称各向同性,并考虑了电势沿径向非均匀分布的影响.挠曲电圆板的振动模态的解析解表明其与压电圆板的振动模态完全不同,这是由于应变梯度局部破坏晶体的反演对称从而在圆板中引起的力电耦合导致的.力电耦合振动模态对弯曲和扭转模态更加敏感,本文给出了挠曲电圆板的基本认知,其有助于设计新型挠曲电圆板器件,例如挠曲电反射镜等.

摘要：Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology and engineering condition of Qishan Coal Mine in Xuzhou, the failure characteristics of pump chambers at the –1000 m level show that the main cause can be attributed to the spatial effect induced by intersectional chambers, where one pump is constructed per well. We developed an opti-mized design of the pump room, in which the pump wells in the traditional design are integrated into one compounding well. We suggest that the new design can limit the spatial effect of intersectional chambers during construction given our relevant numerical simulation. The new design is able to simplify the structure of the pump chamber and reduce the amount of excavation required. Based on a bolt-mesh-anchor with a rigid gap coupling supporting technology, the stability of pump chamber can be improved greatly.

摘要：The three-dimensional (3D) deformation effect of the slope engineering underthe step-by-step excavation for the Antaibao surface mine was analyzed using the FLAG^3Dtechnique. An optimal excavated scheme with a relatively steeper slope angle of 47^(。) instead of 30^(。) was successfully implemented at the west wall in the geological section73200 of the mine area, where the 3D effect of the nonlinear large deformation of theslope was taken into account. Based on the above research conclusion, put forward thecountermeasures of shortening mining length, excavating by different regions, timely footbackfilling to protect the excavated slope, and monitoring and feedback adjustment bystudying the nonlinear effect. The results show that these countermeasures are effective incontrolling maximum deformation and increasing the stability of the slope.

摘要：在本研究中,我们提出了由六边形铝板和六根手性排列直杆组成的谷声子晶体.将谷声子晶体引入拓扑绝缘体(TI)系统,通过在频带上实现支持拓扑保护边缘波(TPEWs)的拓扑边缘态,可以在具有界面路径的系统上引导拓扑保护边缘波的传播.本文的手性拓扑边缘态实现机理与镜面对称系统的拓扑边缘态实现机理不完全相同.与传统的打破镜像对称不同,本文通过调节手性单胞中直杆的长度差异而非打破镜面对称,从而在狄拉克点打开了具有拓扑边缘模式间隙的新的完全带隙.我们研究了手性系统中的色散特性,并将色散特性应用于界面上的波导,以获得可设计的路径系统.此外,我们模拟了TPEWs在不同路径下的鲁棒传播,并证明了其对缺陷后向散射的免疫力.最后,证明了手性体系中谷霍尔效应的存在.这一研究结果将为手性材料拓扑状态的进一步研究奠定基础.

摘要：Based on some assumptions,the dynamic governing equation of anchorage system is *** calculation formula of natural frequency and the corresponding vibration mode are ***,the feasibility of the theoretical method is verified by using a specific example combined with other *** is found that the low-order natural frequency corresponds to the first mode of vibration,and the high-order natural frequency corresponds to the second mode of vibration,while the third mode happens only when the physical and mechanical parameters of anchorage system meet certain *** the increasing of the order of natural frequency,the influence on the dynamic mechanical response of anchorage system decreases ***,a calculating method,which can find the dangerous area of anchorage engineering in different construction sites and avoid the unreasonable design of anchor that may cause resonance,is proposed to meet the seismic precautionary *** method is verified to be feasible and effective by being applied to an actual *** study of basic dynamic features of anchorage system can provide a theoretical guidance for anchor seismic design and fast evaluation of anchor design scheme.