大环境下拓扑化栅格地图的多峰定位研究

通过对室内移动机器人定位研究发现,粒子滤波定位算法在较大的环境下效率低而且定位不准确。为了解决这个问题,提出一种基于拓扑化栅格地图的多峰粒子滤波定位方法。根据室内环境的特征不同,将栅格地图中的不同区域划分为若干拓扑节点。拓扑化栅格地图可以将地图的信息表现得更加简洁。通过对地图中不同的节点进行一次预匹配,来加快机器人定位的效率和准确性,同时为了消弭相似节点带来的影响,最后通过多峰粒子滤波的方法完成机器人的定位。实验结果证明该方法可以有效解决大环境中机器人定位不准确和效率低下等问题,可以帮助机器人实现大环境中的准确而快速定位。     

基于点云协方差描述子的多机器人目标识别与编队跟踪

针对多移动机器人目标识别及编队跟踪问题,提出一种基于点云协方差描述子的目标识别方法及编队跟踪控制方法.为降低机器人端机载处理器负荷,基于Web Socket协议搭建网络架构.在此基础上,通过引入点云协方差描述子进行目标检测,并利用支持向量机完成离线建模.结合支持向量机分类器与Kullback-Leibler Divergence(KLD)-Sampling自适应粒子滤波算法,实现目标部分遮挡下的在线识别,得到目标点云跟踪位置信息.利用势场函数和有向刚性图论综合设计编队跟踪控制器,实现多机器人编队目标跟踪.最后通过实物平台进行实验,结果表明,所提出的基于点云协方差描述子的多机器人目标识别与编队跟踪算法,与传统方法相比,跟踪收敛时间缩短4,s,跟踪精度提高约2.5%,,通过搭载有限数量传感器,可以更有效地解决多机器人编队目标跟踪问题.     

人机交互中的人体目标跟踪算法

针对机器人在与人交互过程中对指定人体目标的跟踪容易受到周围其他人体干扰的问题,提出了一种人机交互中的人体目标跟踪算法.将所有干扰区域看作候选目标,通过建立基于重叠率的粒子分布模型,确保粒子集可以通过均值偏移收敛到所有的候选目标,并减少粒子数量.以权重距离总误差和目标尺寸作为聚类条件,将粒子划分到相应的候选目标粒子集中,最后选择最优的候选目标作为跟踪结果.实验结果表明:该算法能够避免周围相似物体的干扰并准确跟踪目标,具有较好的鲁棒性和实时性.     

步行机器人定位系统特征粒子的优化

针对视觉机器人定位问题,提出一种改进的蒙特卡罗定位方法.在特征粒子的观测更新上,用机器人当前位置确定局部地图的范围,用局部地图的搜索方式来匹配不惟一地标,减弱了粒子分布的多值性;并在粒子的重采样过程中应用历史观测信息和运动信息产生新粒子点,使新粒子有效的概率加大,加快了结果的收敛速度.该方法应用于TJArk队四腿机器人上,在2008机器人世界杯足球赛上取得了令人满意的结果.     

移动机器人同时定位和地图创建的一种新方法

为了实现室内环境中移动机器人的同时定位和地图创建，提出了一种新方法，该方法应用顺序蒙特卡罗方法，把定位和地图生成分成状态估计和参数估计，应用多粒子滤波器实现同时估计机器人位置和障碍物位置。环境感知采用机器人自身配置的声纳传感器，应用哈夫变换提取环境障碍物边界特征，用直线近似表示，并提出了一种可靠的特征匹配方法。Pioneer 2移动机器人在实际室内环境中完成的实验证明了该方法的可行性。     

基于激光雷达与视觉信息融合的SLAM方法

单线激光雷达传感器的扫描范围是二维平面,在室内环境中,服务型移动机器人在进行同时定位和地图构建过程中,不在激光雷达扫描平面范围内的障碍物无法被识别,构建的地图中会缺少相应的环境信息。为了获取缺失的环境信息,通过改进粒子滤波Rao-Blackwellized的方法得到移动机器人位姿的估计,将Kinect获取的环境三维信息数据和激光雷达数据融合,使用载有ROS(机器人操作系统)的移动平台Turtlebot2在实际场景中进行实验。实验结果证明,使用融合后的数据信息能得到更加准确的建图和导航效果。     

基于感兴趣区域的机器人抓取系统

智能抓取机器人能够代替人类完成高强度工作,为实现物体的准确定位,提升机器人抓取的成功率,对基于感兴趣区域的机器人抓取系统进行研究。对深度相机进行标定,对深度卷积神经网络损失函数进行改进,使用焦点函数代替传统的交叉熵函数,训练模型,得到目标的类别、二维包络框中目标的像素坐标值与深度值等信息。利用手眼标定方法将深度传感器坐标转换到机械臂基坐标系下,依据相机成像原理完成物体的定位。通过机器人逆运动学求解关节角度,驱动机器人实现抓取。对实验过程进行分析,在aubo_i5机械臂上进行实验验证。实验结果表明,目标的识别定位误差较小,平均精度值提升了2.36%,抓取的平均成功率达到93.4%,较改进前提升了13.4%,能够满足机器人抓取的需求。     

视觉引导下协作机器人抓取技术研究

针对在多物体复杂抓取场景下,协作机器人如何实现能在人机共融的环境中精确抓取特定目标工件及自主避障的问题,提出了一种基于监督学习的视觉引导下的协作机器人抓取方法;首先利用监督学习算法训练和处理待抓取物图像信息,完成对抓取目标特征的快速识别与定位;然后将抓取物的定位信息通过串口通信协议传输给ROS系统控制机器人完成运动规划...     

基于改进粒子群算法的过程神经网络训练

针对过程神经元网络由于模型参数较多,正交基展开后的BP算法不易收敛的问题,结合量子理论,提出一种改进的粒子群算法,并用于过程神经元网络的训练。算法中粒子采用双链结构,用量子位的概率幅对粒子位置编码,通过量子旋转门和量子非门完成粒子的更新与变异,可发挥量子粒子群的群体搜索能力和全局收敛性,有效克服BP算法计算复杂、容易陷入局部最小值等缺陷。以两组二维三角函数的模式分类问题为例,验证算法有效性。结果表明该方法不仅收敛速度快,而且寻优能力强。     

一种基于视觉信息的自主搬运机器人

提出了一种利用视觉信息进行定位和抓取的自主机器人搬运系统,此系统由带有两自由度操作手的轮式移动机器人和远程控制站组成。机器人利用视觉系统识别路标信息,采用MonteCarlo方法进行自定位。当靠近目标物体时,机器人利用视觉系统识别目标,并在利用该信息引导下自动抓取。由于机器人的运行是靠视觉系统获取的路标信息和目标物体信息引导的,同时具有遥操作控制功能,因此该系统能轻松完成复杂环境下搬运物体的任务。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-