Upper Limb Robot Mediated Stroke Therapy—GENTLE/s Approach

Stroke is a leading cause of disability in particular affecting older people. Although the causes of stroke are well known and it is possible to reduce these risks, there is still a need to improve rehabilitation techniques. Early studies in the literature suggest that early intensive therapies can enhance a patient's recovery. According to physiotherapy literature, attention and motivation are key factors for motor relearning following stroke. Machine mediated therapy offers the potential to improve the outcome of stroke patients engaged on rehabilitation for upper limb motor impairment. Haptic interfaces are a particular group of robots that are attractive due to their ability to safely interact with humans. They can enhance traditional therapy tools, provide therapy on demand and can present accurate objective measurements of a patient's progression. Our recent studies suggest the use of tele-presence and VR-based systems can potentially motivate patients to exercise for longer periods of time. The creation of human-like trajectories is essential for retraining upper limb movements of people that have lost manipulation functions following stroke. By coupling models for human arm movement with haptic interfaces and VR technology it is possible to create a new class of robot mediated neuro rehabilitation tools. This paper provides an overview on different approaches to robot mediated therapy and describes a system based on haptics and virtual reality visualisation techniques, where particular emphasis is given to different control strategies for interaction derived from minimum jerk theory and the aid of virtual and mixed reality based exercises.     

基于目标语词汇组合合理性评价的译文选择模型

机器翻译使用计算机实现自然语言的翻译功能,是计算机技术在语言学领域的新兴应用和研究,其中,源语言词汇的译文选择直接决定机器翻译的质量,是人们关注的难题,基于目标语词汇组合合理性评价的模糊分类模型试图以语言学和模糊数学为理论基础,尝试解决歧义词的译文选择问题,将该模型用于英汉机器翻译系统的译文选择实验,具有良好的译文选择性能,它的优势还在于可以同时为全句范围内的所有歧义词选择译文,因此适用于机器翻译的大规模开发任务。     

目标运动对步进频率毫米波雷达图像匹配识别的影响研究

本文首先简单介绍了步进频率信号的数学模型,给出了一维距离像的外形包络表达式。接着,针对某小口径(155mm)高距离分辨率步进频率毫米波雷达导引头,分析了当弹目存在相对运动时的一维距离像数学模型。按照这一模型,通过计算机对实际系统的模拟仿真,深入研究了多普勒效应对目标一维距离像的影响。最后,获得了给定高距离分辨率步进频率毫米波雷达中,用一维距离像匹配辨识目标的速度不补偿条件。     

目标反射特性与“猫眼”效应研究

对激光应用技术领域主要涉及的漫反射目标进行反射特性分析,着重对近年来关注较多的光学镜头的"猫眼"效应做技术探讨,给出试验数据,浅析其应用.     

基于隔帧差分向量无穷范数的运动点目标检测

提出了隔帧差分向量无穷范数检测运动目标的数学模型,建立了能够充分发挥该模型能力的并行处理结构体系。由于算法以隔帧差分为基础,所以处理系统不仅能够探测到帧间位移不小于1个像元的点目标,而足可以探测列帧间位移小于1个像元而多帧累积位移大子1个像元的运动点目标,使算法探测与识别目标的能力大大提高。实验结果表明了算法的有效性。     

Efficacy of intramammary tilmicosin and risk factors for cure of Staphylococcus aureus infection in the dry period

The objective ofthis study was to evaluate the efficacy of intramammary tilmicosin, administered at drying-off, for eliminating Staphylococcus aureus infection, and to identify risk factors for S. aureus cure during the dry period. A total of 219 naturally infected cows, representing 308 quarters, were randomized to receive either one of two treatments at drying-off. Cows received either an intramammary infusion of 500 mg of benzathine cloxacillin, or a sterile solution containing 1,500 mg of tilmicosin. All cows had quarter milk samples taken aseptically three times before dry-off, and at wk 1, 2, and 4 of the subsequent lactation. Overall, 62% of cows and 67.5% of quarters infected with S. aureus cured during the dry period. The cure following administraton of tilmicosin was 67.3 and 72.5% for cows and quarters, respectively. By comparison, the cure achieved with cloxacillin was 56.9 and 62.9% of cows and quarters. Cows receiving tilmicosin were 2.1 times more likely to cure. The cure rate for cows decreased as the linear score on the last DHI test increased, and as the amount of S. aureus being shed increased. Quarters that cultured positive multiple times before drying-off were less likely to cure. Staphylococcus aureus infections located in front quarters of the udder were 2 times more likely to cure than those in hind quarters. Results of this study demonstrate that intramammary tilmicosin at drying-off is efficacious in curing existing S. aureus during the dry period. Risk factors associated with the cure of S. aureus were identified.     

Molecular Tissue Engineering：Concepts,Status and Challenge

Tissue engineering has confronted many diffculties mainly as follows:1) How to modulate the adherence,proliferation,and oriented differentiation of seed cells,especially that of stemcells.2)Massive preparation and sustained controllable delivery of tissue inducing factors or plasmid DNA,such as growth factors,angiogenesis stimulators,and so on.3) Development of “intelligent biomimetic materials” as extracellular matrix with a good superficial and sturctural compatibility as well as biological activity to stimulate predictable,controllable and desirable responses under defined conditions.Molecular biology is currently one of the most exciting fields of research across life sciences,and the advances in it also bring a bright future for tissue engineering to overcome these difficulties.In recent years,tissue engineering benefits a lot from molecular biology.Only a comprehensive understanding of the involved ingredients of tissue engineering(cells,tissue inducing factors,genes,biomaterials) and the subtle relationships between them at molecular level can lead to a successful manipulation of reparative processes and a better biological substitute.Molecular tissue engineering,the offspring of the tissue engineering and molecular biology.has gained an increasing importance in recent years.It offers the promise of not simply replacing tissue,but improving the restoration.The studies presented in this article put forward this new concept for the fist time and provide an insight into the basic principles,status and challenges of this emerging technology.     

ISAR机动目标的平动补偿和瞬时成像研究

机动目标成像近年来受到广泛注意.本文首先讨论平动补偿,它通常可以分解为两步进行──包络对齐和自聚焦,分析表明,针对平稳目标的包络对齐方法仍然适用于机动目标,而根据相干积累原理,已有的自聚焦方法从理论上和实际上都不是最优的,我们提出适用于机动目标和平稳目标的迭代相干积累自聚焦(ICSA)算法,PGA(相位梯度算法)是ICSA算法的一个特例; 然后,本文讨论机动目标的瞬时成像,它实际上是一个瞬时谱估计问题,已有的一些瞬时成像方法只适用于散射点子回波为线性调频信号(多普勒分布为直线).针对时频分布为非直线的情况,我们提出用自适应窗短时chirplet分解方法估计信号的瞬时频率和瞬时幅度,并结合"洁净"技术,提出了快速自适应窗短时chirplet分解成像(ACDI)算法.实测数据的处理表明本文提出ICSA算法和ACDI算法是有效的.     

基于XML的目标情报浏览系统设计与实现

针对目标情报数据来源广泛、数据格式种类多、数据量大等特点,研究了目标情报的数据结构,建立了基于文件系统和XML的目标情报数据模型.对基于此情报数据模型的情报浏览系统进行了设计和实现,其中主要介绍了系统的设计思想、GIS平台的选择、体系结构设计、情报信息访问引擎以及系统的主要功能.总结了系统的特点,主要包括:独特的情报数据模型、层次化和组件化的体系结构、统一的系统控制以及树型结构的情报管理模式等.     

As-IPDA算法在OTHR航迹维持中的应用

天波超视距雷达(OTHR)具有的低数据率、低检测概率和低量测精度特征对目标跟踪提出挑战;由于对航迹、航迹存在概率的平滑作用,基于状态扩维IPDA(As-IPDA)算法在目标跟踪中得以很好应用,文章把As-IPDA算法引入到天波超视距雷达目标跟踪环境中;仿真结果表明,与传统的概率多假设跟踪(PMHT)算法相比,As-IPDA算法在目标跟踪精度、失跟率以及实时性方面都有满意的结果,从而验证了该算法在天波超视距雷达目标跟踪中的有效性、可行性.