摘要：In this paper, high density of dislocations, grain boundaries and nanometer-scale α precipitates were intro- duced to a metastable Ti-36Nb-5Zr alloy （wt%） through a thermo-mechanical approach including severe cold rolling and short-time annealing treatment. The martensitic trans- formation was retarded, and the β phase with low content of β stabilizers was retained at room temperature after the thermo-mechanical treatment. As a result, both low mod- ulus （57 GPa） and high strength （950 MPa） are obtained. The results indicate that it is a feasible strategy to control martensitic transformation start temperature through microstructure optimization instead of composition design, with the aim of fabricating low modulus β-type Ti alloy.

摘要：A compacted and low-offset low-power CMOS am- plifier for biosensor application is presented in this paper. It includes a low offset Op-Amp and a high precision current reference. With a novel continuous-time DC offset rejection scheme, the IC achieves lower offset voltage and lower power consumption compared to previous designs. This configuration rejects large DC offset and drift that exist at the skin-electrode interface without the need of external components. The proposed amplifier has been implemented in SMIC 0.18-μm 1P6M CMOS technol-ogy, with an active silicon area of 100 μm by 120 μm. The back-annotated simulation results demonstrated the circuit features the systematic offset voltage less than 80 μV, the offset drift about 0.27 μV/℃ for temperature ranging from –30℃ to 100℃ and the total power dissipation consumed as low as 37.8 μW from a 1.8 V single supply. It dedicated to monitor low amplitude biomedical signals recording.

摘要：针对车间生产因少量员工缺勤而造成生产效率大幅度降低的问题,利用RFID和Zig Bee建立数据采集和信息传输的传感器网络;采用自适应遗传算法对无线传感器网络采集到的数据进行数据优化,建立了优化调度的设计模型;并将优化后的结果应用于生产调度。在人员调动较少的前提下,达到了生产效率最大化的预期目标。经仿真实验验证,优化后的结果能使产量提高10%。

摘要：随着海岸侵蚀和海岸线后退,人类的生存和生活环境遭到威胁。目前常用的海岸防护措施极易遭到自然灾害破坏,不经济、不环保且耗费大量维修费用,而微生物诱导碳酸钙沉淀(MICP)技术可以显著改善土体强度、刚度、渗透性及抗液化性能,并且相比于传统土体改良工艺,其绿色环保、环境友好型特点更加符合可持续发展理念,在砂土体加固领域有着非常广阔的工程应用前景。系统地总结了国内外关于微生物法加固砂土堤岸的室内及现场试验研究的最新成果,并对微生物固化土体的力学特性进行了研究论述。

摘要：Surface topographies such as micrometric edges and grooves have been widely used to improve neuron ***,finding the mechanism of neuron–surface interactions on grooved substrates remains a *** this work,PC12 cells and chick forebrain neurons(CFNs)were cultured on grooved and smooth polyacrylonitrile *** was found that CFNs showed a tendency of growing across groove ridges;while PC12 cells were only observed to grow in the longitudinal direction of *** further investigate these observations,a 3D physical model of axonal outgrowth was *** this model,axon shafts are simulated as elastic 3D beams,accounting for the axon outgrowth as well as the focal contacts between axons and ***,the bending direction of axon tips during groove ridge crossing is governed by the energy minimization *** physical model predicts that axonal groove ridge crossing is contributed by the bending compliance of axons,caused by lower Young’s modulus and smaller *** work will aid the understanding of the mechanisms involved in axonal alignment and elongation of neurons guided by grooved substrates,and the obtained insights can be used to enhance the design of instructive scaffolds for nerve tissue engineering and regeneration applications.

摘要：通过对北徐楼煤矿3下煤层开采的顶板充水因素进行分析,用公式法计算导水裂缝带高度,从而确定防水安全煤岩柱高度,论证地表水(湖水)是否对煤层开采产生影响。

摘要：目前现有的采茶末端执行器多为剪切式,不适用于高档名优绿茶的采摘,为解决这一问题,提出一种模仿人工“提手采”动作的柔性采摘指机构。对采摘指结构参数进行有限元分析,使上、下夹爪在夹持中产生可感知的弹性形变。基于该机构,设计采摘指电动控制系统。采用嵌入式处理器,通过步进电机控制两对夹爪的开合和提拉动作,并设计测力电路,实时检测夹持力,以提拉方式实现对嫩芽的采摘。分析得到夹爪所受的最大应力为0.16 MPa,夹爪的最大形变为0.00038 mm。依此结果制作样机,并进行采摘试验。试验结果表明:柔性采摘指能有效实现一芽一叶的采摘,成功率达到92.5%,验证了该采摘指的可行性,具有应用价值。

摘要：高熵合金因其优异的力学性能、耐腐蚀性和热稳定性,成为近年来材料科学领域的研究热点。然而,传统制备工艺面临的成分均匀性不足、高裂纹敏感性和高成本等问题限制了其工业应用。增材制造技术以其逐层制造、高设计自由度和快速冷却的优势,为高熵合金的复杂结构制备提供了新的解决方案。本文论述了增材制造技术在高熵合金领域的最新研究进展,重点分析了选择性激光熔化、直接能量沉积、电子束熔化等技术在组织调控和性能优化中的应用。研究发现,不同技术在组织控制、性能提升及适用领域方面各具优势,同时也面临裂纹形成、成分偏析和残余应力等共性挑战。通过深入分析工艺的优化策略及其对性能的影响,揭示了增材制造高熵合金组织与性能的内在关联,并提出了未来的发展方向,包括开发新型合金体系、优化工艺参数、提高制造效率以及拓展多功能材料应用。

摘要：大流识别是网络测量中的一项关键基础性工作,目前主流的方法是采用概要型数据结构Sketch快速统计网络流量,进而高效筛选大流.然而,当网络流量发生抖动时,大量分组的急速涌入将导致大流识别精度显著下降.对此,提出一种支持流量抖动的网络大流弹性识别方法RobustSketch.所提方法首先设计基于Sketch循环链的可伸缩小流过滤器,根据实时分组到达速率适应性扩增与缩减其中的Sketch数量,以始终完整记录当前时间周期内所有到达的网络分组,从而确保网络流量抖动出现时仍能精确过滤小流.然后设计基于动态分段哈希的可拓展大流记录表,根据小流过滤器筛选后的候选大流数量适应性增加与减少分段,以完整记录所有候选大流,并保持较高的存储空间利用率.进一步,通过理论分析给出了所提小流过滤器和大流记录表的误差界限.最后,借助真实网络流量样本,对所提大流识别方法RobustSketch进行实验评估.实验结果表明:所提方法的大流识别精确率明显高于现有方法,即使在网络流量抖动时仍能稳定保持在99%以上,而平均相对误差减少了86%以上,有效提升了大流识别的精确性和鲁棒性.

摘要：王草是优质的多年生饲草作物,在我国南方地区广泛种植,具有直立簇生的特征,机械化平茬收获难度大。为此,基于王草机械化收获的技术要求,提出了一种驱动系统技术方案,介绍了其结构组成和工作原理,设计研制了驱动系统。经过理论分析与计算,完成了驱动系统的主要参数匹配,并实现了驱动系统的样机搭载。性能试验表明:样机最高行驶速度可达9.13 km/h,能够在低速挡位内无级变速,直行偏驶率为4.115%,达到了王草机械化收获的作业要求。