仿人机器人摆动脚落地碰撞补偿控制研究

分析了仿人机器人摆动脚落地时的运动误差和摆动脚与地面的碰撞效应,提出了基于运动误差的摆动脚落地补偿控制策略,根据摆动脚距地面高度误差、摆动脚与支撑脚之间的步距误差,在线分级调整摆动腿髋、膝和脚踝关节前摆的运动角度,补偿摆动脚距地面高度和步距.样机实验证明,机器人摆动脚运动误差减小,实际落地时间趋近期望时刻,摆动脚与地面的碰撞冲击力减小且变化平缓,行走稳定性改善.     

一种新型高速码垛机械手的设计与实现

针对包装袋规格和码垛技术要求,提出一种新型的高速码垛机械手的设计方案.该方案采用气压驱动,并通过手指开合机构、侧板夹紧机构和压袋机构,实现包装袋的可靠抓包、搬运和码放等动作.在此基础上,通过详细分析与计算,完成了该机械手的结构设计,并在Pro/E平台中建立了该机械手的三维CAD模型.对该机械手的动作规划、动力学计算以及气动系统等问题进行了分析与研究.仿真结果表明,该机械手能够在规定的时间内完成规定动作.     

汽轮发电机组振动故障诊断的模糊输入方法

针对汽轮发电机组振动故障的特点,构造了一模糊神经网络（ＦＮＮ）诊断模型,讨论了网络的多种模糊化输入,输出方式,并对两种模糊输入方法进行了对比分析。最后运用该诊断方法与传统的ＢＰ网络诊断方法进行比较。结果表明：模糊神经网络诊断方法对汽轮发电机组振动故障的识别是有效的,且在分类模糊边界数据时优于ＢＰ网络诊断方法。     

Local charge of the ν = 5/2 fractional quantum Hall state

Electrons moving in two dimensions under the influence of strong magnetic fields effectively lose their kinetic energy and display exotic behaviour dominated by Coulomb forces. When the ratio of electrons to magnetic flux quanta in the system (ν) is near 5/2, the electrons are predicted to condense into a correlated phase with fractionally charged quasiparticles and a ground-state degeneracy that grows exponentially as these quasiparticles are introduced. The only way for electrons to transform between the many ground states would be to braid the fractional excitations around each other. This property has been proposed as the basis of a fault-tolerant quantum computer. Here we present observations of localized quasiparticles at ν = 5/2, confined to puddles by disorder. Using a local electrometer to compare how quasiparticles at ν = 5/2 and ν = 7/3 charge these puddles, we were able to extract the ratio of local charges for these states. Averaged over several disorder configurations and samples, we found the ratio to be 4/3, suggesting that the local charges are = e/3 and = e/4, where e is the charge of an electron. This is in agreement with theoretical predictions for a paired state at ν = 5/2. Confirming the existence of localized e/4 quasiparticles shows that proposed interferometry experiments to test statistics and computational ability of the state at ν = 5/2 would be possible.     

基于浓缩数据立方的内存实化数据立方的构建

为提高联机分析查询的速度,在浓缩数据立方的基础上,构建了元组级别的内存实化方法.以内存空间至少能容纳最细粒度数据小方为前提,在内存中构造两级Hash结构:第一级Hash结构存放最细粒度的数据小方以保证所有查询都可从内存中响应;第二级Hash结构按照聚集度高的小方元组优先、相同聚集度情况下尺寸小的小方中元组优先的选择策略,选择立方元组在内存实化.处理点查询时,首先从第二级结构中直接查找满足条件的立方元组.若对范围查询,则需从第一级结构中计算获得.由于最细粒度立方元组和其他一些粗粒度元组都在内存中,避免了费时的外存存取,数据立方更新和维护代价也得以降低.     

基于Matlab的双足机器人动力学仿真及仿生控制平台

针对仿生控制的特点,构建了一种Matlab环境下的双足机器人动力学仿真及仿生控制平台。为了充分利用关节自身的被动特性,描述了由非外界约束引起的自由度变化,以及双足机器人在运动相态间的合理切换。同时,考虑到碰撞是机器人运动的固有特性,建立了包括碰撞在内的混合动力学模型,最终实现控制器与机器人、环境的耦合。在此平台上,对设计的仿生控制算法进行了仿真：借助机器人自身运动状态和环境交互信息,协调各个关节的动作时序,实现了低能耗的稳定行走。结果表明,该平台为双足机器人仿生控制及其运动特性分析提供了有效的仿真手段。     

Analysis of the DNA sequence and duplication history of human chromosome 15

Here we present a finished sequence of human chromosome 15, together with a high-quality gene catalogue. As chromosome 15 is one of seven human chromosomes with a high rate of segmental duplication, we have carried out a detailed analysis of the duplication structure of the chromosome. Segmental duplications in chromosome 15 are largely clustered in two regions, on proximal and distal 15q; the proximal region is notable because recombination among the segmental duplications can result in deletions causing Prader-Willi and Angelman syndromes. Sequence analysis shows that the proximal and distal regions of 15q share extensive ancient similarity. Using a simple approach, we have been able to reconstruct many of the events by which the current duplication structure arose. We find that most of the intrachromosomal duplications seem to share a common ancestry. Finally, we demonstrate that some remaining gaps in the genome sequence are probably due to structural polymorphisms between haplotypes; this may explain a significant fraction of the gaps remaining in the human genome.     

基于SIMULINK的Fuzzy-PID控制器设计

设计了一种Fuzzy-PID控制算法，利用MATLAB的SIMULINK进行仿真研究，结果表明，该控制器具有较强的抗干扰能力和鲁棒性，有较好的动、静态控制精度．     

Differential roles of MDA5 and RIG-I helicases in the recognition of RNA viruses

The innate immune system senses viral infection by recognizing a variety of viral components (including double-stranded (ds)RNA) and triggers antiviral responses. The cytoplasmic helicase proteins RIG-I (retinoic-acid-inducible protein I, also known as Ddx58) and MDA5 (melanoma-differentiation-associated gene 5, also known as Ifih1 or Helicard) have been implicated in viral dsRNA recognition. In vitro studies suggest that both RIG-I and MDA5 detect RNA viruses and polyinosine-polycytidylic acid (poly(I:C)), a synthetic dsRNA analogue. Although a critical role for RIG-I in the recognition of several RNA viruses has been clarified, the functional role of MDA5 and the relationship between these dsRNA detectors in vivo are yet to be determined. Here we use mice deficient in MDA5 (MDA5-/-) to show that MDA5 and RIG-I recognize different types of dsRNAs: MDA5 recognizes poly(I:C), and RIG-I detects in vitro transcribed dsRNAs. RNA viruses are also differentially recognized by RIG-I and MDA5. We find that RIG-I is essential for the production of interferons in response to RNA viruses including paramyxoviruses, influenza virus and Japanese encephalitis virus, whereas MDA5 is critical for picornavirus detection. Furthermore, RIG-I-/- and MDA5-/- mice are highly susceptible to infection with these respective RNA viruses compared to control mice. Together, our data show that RIG-I and MDA5 distinguish different RNA viruses and are critical for host antiviral responses.     

基于碰撞反馈的冗余机器人避障规划算法

针对复杂封闭类管道零件喷涂过程中避障的需求,该文提出了一种基于碰撞反馈的冗余机械臂避障算法,该算法利用投影相交法进行碰撞检测,将碰撞类型分为可规避碰撞及不可规避碰撞两类：针对可规避碰撞,提出了关节权值动态调整算法,通过加强对碰撞关节的运动限制,同时放宽对其他关节的约束,实现自运动优化避障;针对不可规避碰撞,提出了基于\"杠杆原理\"的调整方法,通过调整目标点的姿态实现避障。最后,通过设计关节加速度的优化函数对轨迹进行优化以减少机器人的冲击惯性。通过仿真实验,验证了上述算法的可行性。