高/低通复合多通道系统辨识的测试信号设计

从频域的角度研究了二进制多频序列(Muhifrequency Binary Sigal).从该信号的基本特点入手,通过对信号变化疏密的设计,调整信号的频谱分布.当已知待测系统的频谱集中在某些频段时,选取适当的二进制多频序列信号,能使测试信号的频谱也集中在那些频段,能充分地利用测试信号.大大提高了信噪比.设计出高频和低频复合的二进制多频序列信号.应用于一个通道是高通的,另一个通道是低通的二输入系统,能同时充分激励2个通道,取得较好的辩识效果.仿真算例可以看出有效性.     

An SPH-based mass transfer model for simulating hydraulic characteristics and mass transfer process of dammed rivers

Engineering with Computers - Aerated flow characterized by complex mass transfer processes with multiple hydraulic properties is a common enviro-hydraulics phenomenon, which have a variety of...     

Tissue dynamics spectroscopy for three-dimensional tissue-based drug screening

Tissue dynamics spectroscopy combines dynamic light scattering with short-coherence digital holography to capture intracellular motion inside multicellular tumor spheroid tissue models. The cellular mechanical activity becomes an endogenous imaging contrast agent for motility contrast imaging. Fluctuation spectroscopy is performed on dynamic speckle from the proliferating shell and hypoxic core to generate drug-response spectrograms that are frequency versus time representations of the changes in spectral content induced by an applied compound or an environmental perturbation. A combination of 28 reference compounds and conditions applied to rat osteogenic UMR-106 spheroids generated spectrograms that were crosscorrelated in a similarity matrix used for unsupervised hierarchical clustering of similar compound responses. This work establishes the feasibility of tissue dynamics spectroscopy for three-dimensional tissue-based phenotypic profiling of drug response as a fully endogenous probe of the response of tissue to reference compounds.     

Real-time foveation filtering using nonlinear Mipmap interpolation

In recent years, several techniques have been proposed to simulate the gaze effect of the Human Visual System (HVS). It is believed that this effect is due to the foveation filtering. Current techniques to simulate the foveation filtering in computer graphics are either slow or suffer from artifacts and limitations. In this paper, we present a new approach of foveation filtering based on the Mipmap Pyramid of the current view by considering the relationship between the Gaussian kernel and Mipmap level. Due to the nonlinear Mipmap interpolation under the Bilateral Filtering scheme, we are able to simulate the foveation filtering more naturally and efficiently than in previous work. Moreover, a detail enhancement method based on the Cornsweet illusion is proposed to augment the gazing effect. We demonstrate our new approach with a variety of examples and provide comparisons with recent approaches.     

搭建网络服务器实验室环境

随着招生规模和高等教育的深化改革的急剧扩大,许多高校都陷入了实验教学的困境。该文利用目前流行的虚拟机软件VMware作为建立虚拟机的工具,以Web服务器为例,最后对所构建的虚拟网络服务器实验环境进行测试,达到与在真机上实验的效果相似。     

基于完备抽象解释的模型检验CTL公式研究

在模型检验中,抽象是解决状态空间爆炸问题的重要方法之一.给定具体Kripke结构和时序描述语言CTL,基于抽象解释框架以及完备抽象解释和性质强保留之间的关系,抽象模型最小精化使得CTL性质强保留,可转换为抽象解释中抽象域的最小完备精化,并且总是存在抽象域的最小完备精化.根据状态标签函数确定初始抽象域,然后通过不动点求解,获得对CTL标准算子完备的最小抽象域,并依据此抽象域求得CTL性质强保留的最优抽象状态划分,最后构造出CTL性质强保留且最优的抽象状态转换系统.并指出了抽象域对CTL标准算子是完备的当且仅当抽象域对补集和标准前向转换是完备的.     

基于校准靶的C形臂相机模型自动校准方法

根据校准靶标志点影像的特点,提出一种自动的离线C形臂相机模型校准方法。应用聚类算法实现标志点信息的自动识别,通过行列索引表简化标志点网格姿态的识别,自动建立标志点在影像坐标系和空间坐标系下坐标的对应关系,经几何变形校正后,实现C形臂相机的校准。实验数据证明,该方法具有良好的鲁棒性,误差小于1 mm,可应用于基于术中C形臂X线影像的手术导航系统。     

基于自证明公钥和零知识证明的身份认证协议

在分析几种典型零知识身份认证协议的基础上,利用Girault自证明公钥原理、结合椭圆曲线公钥密码的优点提出一种基于自证明公钥和零知识证明的身份认证协议,并为协议增加了密钥协商功能。分析表明该方案具有较高的安全性,与同类方案相比,该方案对存储空间、网络通信量和计算开销的要求较低,有较高的效率。     

基于流形学习和SVM的Web文档分类算法

为解决Web文档分类问题,提出一种基于流形学习和SVM的Web文档分类算法。该算法利用流形学习算法LPP对训练集中的高维Web文档空间进行非线性降维,从中找出隐藏在高维观测数据中有意义的低维结构,在降维后的低维特征空间中利用乘性更新规则的优化SVM进行分类预测。实验结果表明该算法以较少的运行时间获得更高的分类准确率。