摘要：岩体结构的复杂性会导致地下工程在施工过程中的高度不确定性和风险。本研究采用类岩材料室内试验和二维颗粒流数值模拟相结合的方式,分别研究了四心圆形隧道和马蹄形隧道周围的主应力和主应变分布。数值结果表明,既有的裂隙倾角组合直接影响隧道周围的主应力、主应变分布和破坏特征。预裂隙的倾角绝对值越大,两类隧洞均在拱腰(M-4和M-5)附近的挤压劈裂破碎程度逐渐加剧,“V”形破坏区也越大。随着预裂隙倾角绝对值的减小(60°→45°→30°),预裂隙的侧壁压应力集中程度逐渐增加。四心圆形隧道和马蹄形隧道周围产生的裂缝类型不同。当裂隙近于垂直时,对四心圆形隧洞侧壁受力影响较大;而当裂隙近于水平时,对马蹄形隧洞边墙受力影响较大。以上发现,为隧道支护结构的局部加固设计提供了理论支持。

摘要：本文基于Winkler地基Timoshenko梁理论,考虑水平地基摩阻力及盾构隧道环缝接头塑性变形特征,提出了一种跨断层盾构隧道纵向响应解析模型。首先,以正断层错动工况为例,采用数值模拟方法验证解析解的合理性。然后,分析了盾构隧道环缝接头的塑性变形特征,并通过参数分析讨论了影响隧道纵向变形响应的因素。研究结果表明:断层错动下盾构隧道环缝接头张开及错台变形均较为显著,解析模型计算得到的盾构隧道纵向力学响应特征与数值模型计算结果规律一致;在断层错动10 cm时,盾构隧道环缝接头已产生显著的塑性变形;在穿越活动断层工况中,地层对隧道纵向变形的限制作用更加明显,导致环缝接头变形量更大;地基刚度越大,盾构隧道纵向变形响应越显著。当不考虑断层破碎带宽度时,计算得到隧道纵向力学响应值是偏安全的;在隧道环缝接头弹性变形阶段,弹性弯曲刚度有效率越大,接头张开量越小;在环缝接头塑性变形阶段,盾构隧道二次塑性等效弯曲刚度比越大,盾构隧道环缝接头塑性变形越小。本文提出的解析模型可以预测跨断层盾构隧道环缝接头变形,同时可以为盾构隧道接缝防水设计提供理论指导。

摘要：This paper studies the consistency of the extended Kalman filter(EKF) for a kind of nonlinear systems. Based on the EKF algorithm, the authors propose the quasi-consistent EKF(QCEKF)as well as the tuning law for its parameters. The quasi-consistency of the proposed algorithm is ***, the feasibility of the algorithm is illustrated by the numerical simulation on an orbit determination example.

摘要：The dissolution behaviors of Ta2O5,Nb2O5 and their mixture in KOH and H2O system were investigated.A L9(34) orthogonal design was used to study the effects of reaction temperature,mass ratio of KOH to Ta2O5,and reaction time on the dissolution rate of *** was found that the effect of reaction temperature on the dissolution rate of tantalum was much greater than that of the other *** results of factorial experiments showed that Ta2O5 was mainly transformed into insoluble potassium tantalate at low temperature(350 ℃) and transformed into soluble potassium tantalate at high temperature(450 ℃).The insoluble potassium tantalate was analyzed by XRD,which was proved to be ***,almost all Nb2O5 was transformed into soluble potassium niobate at 350-450℃.As for the mixture of Ta2O5 and Nb2O5,the dissolution rate of tantalum increased and the dissolution rate of niobium decreased as an interaction existed between niobium and *** increasing the mole ratio of Nb2O5 to Ta2O5 in the mixture was beneficial to the dissolution of both Ta2O5 and *** addition,the mechanism of the interaction between niobium and tantalum was also investigated through phase and chemical analysis.

摘要：For different kinds of rocks,the collapse range of tunnel was studied in the previously published ***,some tunnels were buried in soils,and test data showed that the strength envelopes of the soils followed power-law failure *** this work,deep buried highway tunnel with large section was taken as objective,and the basic expressions of collapse shape and region were deduced for the highway tunnels in soils,based on kinematical approach and power-law failure *** order to see the effectiveness of the proposed expressions,the solutions presented in this work agree well with previous results if the nonlinear failure criterion is reduced to a linear Mohr-Coulomb failure *** present results are compared with practical projects and tunnel design *** numerical results show that the height and width of tunnel collapse are greatly affected by the nonlinear criterion for the tunnel in soil.

摘要：The ability to finely control the structure of protein folds is an important prerequisite to functional protein design. The TIM barrelfold is an important target for these efforts as it is highly enriched for diverse functions in nature. Although a TIM barrel proteinhas been designed de novo, the ability to finely alter the curvature of the central beta barrel and the overall architecture of the foldremains elusive, limiting its utility for functional design. Here, we report the de novo design of a TIM barrel with ovoid (twofold)symmetry, drawing inspiration from natural beta and TIM barrels with ovoid curvature. We use an autoregressive backbonesampling strategy to implement our hypothesis for elongated barrel curvature, followed by an iterative enrichment sequencedesign protocol to obtain sequences which yield a high proportion of successfully folding designs. Designed sequences arehighly stable and fold to the designed barrel curvature as determined by a 2.1Å resolution crystal structure. The designs showrobustness to drastic mutations, retaining high melting temperatures even when multiple charged residues are buried in thehydrophobic core or when the hydrophobic core is ablated to alanine. As a scaffold with a greater capacity for hosting diversehydrogen bonding networks and installation of binding pockets or active sites, the ovoid TIM barrel represents a major steptowards the de novo design of functional TIM barrels.

摘要：在地面上的一个严肃环境，自从人首先由飞目标探索了空间，在空间的零严肃的环境的二个飞的目标的接触过程的模拟是一个挑战性的问题。Hardware-in-the-loop (HIL ) 模拟是一个重要、有效的方法在空间测试真实停靠机制的可用性，可靠性，和安全。为 HIL 模拟系统有四个主要问题：能够高频率反应，高运动精确，高速度，和快速的加速的模拟器的设计；为模拟失真的赔偿；为 HIL 模拟进程的一个控制模型的设计；并且试验性的确认。这里，我们与 6-DOF 3-3 建议一个新奇 HIL 模拟器系统垂直平行机制和 3-DOF 3-PRS 平行机制；发现模拟失真的原则；为模拟器的力量测量系统，动态反应，和结构的动力学介绍失真赔偿模型；并且为 HIL 模拟过程提供一个控制模型。二种实验在被动未受潮的有弹性的杆和停靠机制上被执行测试他们的表演并且验证 HIL 模拟器的有效性和可用性。在这份报纸建议的 HIL 模拟系统为开发停靠的空格是有用的， berthing， refueling，修理，升级，搬运，并且 rescuing 技术。

摘要：我们将实体嵌入问题看作同时完成两个不同但相关的嵌入任务(实体嵌入和关系嵌入)的联合优化问题,并在联合嵌入框架下求解该问题。在该嵌入框架下,我们设计了联合评分函数,用以对实体和关系间的相关性实例进行量化评价,并将评分函数融入最大间隔学习方法中,使用知识库中的上下文信息学习实体与关系的嵌入向量。通过求解联合优化问题,我们的设计有效地表达了嵌入空间的固有拓扑结构。实验结果证实了我们的嵌入框架在表达不同关系的语义相关性和进行知识推理中的关系预测时的有效性。

摘要：Darcy's law only applying to the flow domain is extended to the entire fracture network domain including the dry *** partial differential equation(PDE) formulation for unconfined seepage flow problems for discrete fracture network is established,in which a boundary condition of Signorini's type is prescribed over the potential seepage *** order to reduce the difficulty in selecting trial functions,a new variational inequality formulation is presented and mathematically proved to be equivalent to the PDE *** numerical procedure based on the VI formulation is proposed and the corresponding algorithm has been *** a continuous penalized Heaviside function is introduced to replace a jump function in finite element analysis,oscillation of numerical integration for facture elements cut by the free surface is eliminated and stability of numerical solution is *** numerical results from two typical examples demonstrate,on the one hand the effectiveness and robustness of the proposed method,and on the other hand the capability of predicting main seepage pathways in fractured rocks and flow rates out of the drainage system,which is very important for performance assessments and design optimization of complex drainage system.

摘要：Vehicular ad hoc networks(VANets) experiment system is ***,characteristics and research fields of VANets are introduced *** to the characteristics of VANets,key modules that multi-vehicle ad hoc experiment system needs are designed,and each module's function and practice requirement is *** reliability of experiment system is tested primarily using three experiment scenes of multi-vehicle ad hoc network,car following and wireless *** experiment result shows that multi-vehicle ad hoc experiment system has the capability of the correlated experiment of VANets.