摘要：A method of topology synthesis based on graph theory and mechanism combination theory was applied to the configuration design of locomotion systems of lunar exploration rovers(LER).Through topology combination of wheel structural unit,suspension unit,and connecting device unit between suspension and load platform,some new locomotion system configurations were proposed and the metrics and indexes to evaluate the performance of the new locomotion system were *** evaluation and comparison between two LER with locomotion systems of different configurations were *** analysis results indicate that the new locomotion system configuration has good trafficability performance.

摘要：In this paper,we study cross-layer scheduling scheme on multimedia application which considers both streaming traffic and data traffic over cognitive ad hoc networks.A cross-layer design is proposed to optimize SU's utility,which is used as an approach to balance the transmission efficiency and heterogeneous traffic in cognitive ad hoc networks.A framework is provided for utility-based optimal subcarrier assignment,power allocation strategy and corresponding modulation scheme,subject to the interference threshold to primary user(PU) and total transmit power *** learning is adopted in subcarrier allocation strategy to avoid collision and alleviate the burden of information exchange on limited common control channel(CCC).In addition,the M/G/l queuing model is also introduced to analyze the expected delay of streaming *** results are given to demonstrate that the proposed scheme significantly reduces the blocking probability and outperforms the mentioned single-channel dynamic resource scheduling by almost 8%in term of system utility.

摘要：利用太阳能将CO_(2)转化为增值燃料,对于实现全球碳中和的目标具有重要意义,而光生电荷的有效分离是提高光催化CO_(2)还原效率的重要影响因素.在此,我们报道了一种简易的原位剥离和转化策略,将CeO_(2)纳米颗粒均匀分布在超薄多孔C_(3)N_(4)纳米片上,合成了新型的CeO_(2)/C_(3)N_(4)异质结构.C_(3)N_(4)的超薄多孔结构不仅可以增加比表面积以提供更多的活性位点,还可以有效缩短光生电子空穴的迁移距离以避免复合.此外,高度分散的CeO_(2)与C_(3)N_(4)之间具有紧密的界面接触,使更多的电荷通过界面进行转移.合成的CeO_(2)/C_(3)N_(4)异质结构具有带隙匹配的Z型结构,可以有效延长光诱导电荷载流子的寿命并提升光催化剂的氧化还原能力.与传统块状C_(3)N_(4)相比,合成的CeO_(2)/C_(3)N_(4)异质结在没有贵金属作为助催化剂和没有牺牲剂条件下显示出约5倍的CO_(2)光还原性能的提升.这项工作为用于可持续能源转换的直接Z型光催化剂的设计和实际应用提供了一种新策略.

摘要：This paper proposes a heading fault tolerance scheme for operation-level underwater robots subject to external *** scheme is based on a double-criterion fault detection method using a redundant structure of a dual electronic ***,two subexpansion Kalman filters are set up to fuse data with an inertial attitude measurement ***,fault detection can effectively identify the fault sensor and fault ***,a fault-tolerant algorithm is used to isolate and alarm the faulty *** program can effectively detect the constant magnetic field interference,change the magnetic field interference and small transient magnetic field interference,and conduct fault tolerance control in time to ensure the heading accuracy of the *** verification shows that the system is practical and effective.

摘要：提出了一种基于石英晶体温度频率特性的石英音叉微谐振式温度传感器。通过理论分析的方法对传感器进行设计,并采用有限元仿真对传感器的结构参数进行优化。采用光刻和蚀刻微加工技术制造石英音叉谐振器,对石英音叉温度传感器样机的频率温度特性进行实验研究。实验结果表明:石英音叉温度传感器的标准谐振频率为36.545kHz,灵敏度为-1.9Hz/℃,在-20到100℃的温度范围内,其非线性误差小于0.18%,迟滞为0.02%,与理论研究相吻合。该传感器具有高精度、高灵敏度、低功耗和低成本的特点,为高性能温度测量提供较好的解决方案。

摘要：高强复合材料的低位错存储性能及其引发的强塑倒置问题阻碍了该系列材料的进一步发展.本文通过新颖的形变驱动冶金方法,设计了一种巧妙的具有粗细晶粒异质结构的纳微混合SiC增强铝基复合材料.基于背应力理论对累积的几何必须位错和晶内分散的SiC颗粒进行调控,使得背应力与外在施加应力保持动态平衡.这是本策略实现材料强塑性协同的关键.所设计的SiC_(5np-5μp)/Al复合材料的极限抗拉强度和均匀伸长率分别为324 MPa和12.9%,达到SiC_(10μp)/Al抗拉强度的181%,而塑性仅损失了约3%.因此,本文提供了一种基于背应力优化的强度-塑性协同新策略.

摘要：单价选择性阳离子交换膜(M-CEMs)已被广泛应用于环境修复和能量收集等领域,例如,从卤水和海水中提取Na^(+)或Li^(+)。然而,由于膜结构和材料的限制,M-CEMs存在渗透选择性低的问题。在此,我们提出了一种简单的方法以构建具有电荷Janus结构的新型M-CEMs,该结构由荷正电的均苯三甲酸/聚乙烯亚胺选择层和荷负电的商业阳离子交换膜(CEM)组成。选择性电渗析(SED)分析结果表明,具有电荷Janus结构的M-CEMs可以有效抑制多孔阳离子交换膜中存在的阴离子迁移问题,因而使这种具有电荷Janus结构的M-CEMs具有较高的渗透选择性和总阳离子通量。与最先进的单价选择性阳离子交换膜的分离性能相比,具有电荷Janus结构的M-CEMs对于Na^(+)/Mg^(2+)的最高渗透选择性可以达到145.77,这超过了目前单价选择性阳离子交换膜性能的“上限”,且对于Li^(+)/Mg^(2+)也具有优异的渗透选择性(14.11),在离子分离领域具有巨大的应用潜力。这项研究可以为具有电荷Janus结构的M-CEMs的设计提供新的见解,并应用于不同的环境和能源领域。

摘要：基于混合介质雷诺平均N-S方程,对开放空腔圆柱壳垂直入水运动过程开展了数值研究,得到了压力场、速度场分布,空泡波动、闭合特征,空腔气体涨缩规律,以及流体动力变化规律,并分析了空腔结构在入水运动过程中对流场结构和流体动力的影响。结果表明:液体随气体涨缩同步进出开放端;开放端局部形成波动的压力源和周期性的压力场、速度场分布;入水空泡呈现波动形态,其扩展程度与开放端液体流速相关;空泡内形成气体漩涡,随空腔涨缩往返进出空泡,对空泡闭合具有抑制作用;流体动力呈波动变化规律,频率与气体涨缩频率一致,幅值与气体涨缩程度成正比。开放空腔结构在入水过程中空腔内气体发生涨缩运动,对流场结构和流体动力产生周期性扰动作用,在一定程度上可以减缓冲击、维持空泡及运动的稳定性。

摘要：In terms of lightweight electromagnetic interference(EMI)shielding structural materials,Mg matrix materials have proven to be the best,due to their exciting properties(*** density,high specific strength,good electrical conductivity and excellent EMI shielding properties)and their wide range of applications in lightweighting in electronics,automotive and aerospace *** processing,such as alloying,heat treatment,plastic deformation and composite processing,Mg matrix materials can be obtained with tailorable properties which can play a key role in designing materials for EMI *** work introduces an overview of the research on the EMI shielding properties of Mg matrix materials as well as their EMI shielding mechanisms over the past few decades,focused on the influence of alloying,heat treatment,plastic deformation and composite processing for the EMI shielding properties of Mg matrix *** the end,conclusions and future perspectives are provided.

摘要：基于纳米多晶硅薄膜电阻的多功能传感器由压力传感器和加速度传感器构成。纳米多晶硅薄膜电阻构成的两个惠斯通电桥结构分别设计在方形硅膜表面和悬臂梁根部。采用MEMS技术和CMOS工艺在〈100〉晶向单晶硅片上实现压力/加速度传感器芯片制作,利用内引线技术将芯片封装在一个印刷电路板(PCB)上。在室温下,工作电压为5.0V时,实验结果给出压力传感器灵敏度(a=0)为1.0mV/kPa,加速度传感器灵敏度(p=0)为0.92mV/g,可实现外加压力和加速度的测量,具有较好的灵敏度特性且交叉干扰较弱。