一种基于局部运动特征的视频检索方法

在基于运动内容的视频检索中 ,视频中的局部物体运动常是用户关心的重点。在利用全局运动模型参数对运动估计的基础上 ,提出了一种从一般视频序列中提取局部物体运动矢量的方法 ,并以局部运动矢量场的方向直方图作为检索特征 ,实现了一个基于局部运动信息的视频检索系统。实验表明 :基于局部运动信息的检索机制使该系统能够较好地检索到符合人们主观理解的运动视频内容     

A kernel-driven model of effective directional emissivity fornon-isothermal surfaces

Land surface temperature (LST) is a key geophysical parameter that reflects the combined effects of land surface energy and radiation balance. Remote sensing of LST, however, requires understanding the directional patterns of thermal emission from heterogeneous land surfaces. Recently, semi-empirical, linear, kernel-driven models have been successfully used to describe observed directional patterns of land surface reflectance. Following a similar methodology and based on a recent model of the physics of directional thermal emission from heterogeneous land surfaces, a kernel-driven semi-empirical model for thermal emission is developed using three kernels: (i) an isotropic kernel, corresponding to the gray-body component in a heterogeneous pixel; (ii) a two-layer canopy kernel, derived from a previous conceptual model; and (iii) a geometric optical kernel that accounts for the fact that sunlit parts are hotter than shaded parts in a pixel. The three-kernel model fits 1997 airborne directional thermal brightness data over Avignon, France, very well.     

功率集成光激MOS控制交流多路开关模拟设计

介绍了一种新型功率集成光激MOS控制多路开关，它由双向晶闸管，MOS器件，光电器件组成。此开关通过光电转换来实现强电与弱电之间的隔离，可工作在交流状态，其通态压降低，约在1．5－3V之间，并对其阻断特性，电流特性，开关特性进行了全面的模糊分析，此开关适用于开发各种电源开关产品。     

一种结合解析与离散方法的方向场计算方法

方向场在指纹识别、纹理分类等领域有很重要的应用。文章介绍了两种方向场的计算方法——解析法和离散量化法 ,并对它们进行比较 ,提出一种结合解析法与离散法的算法 ,最后 ,用一幅简单条纹图像来验证本方向场计算方法的计算结果 ,并且给出了指纹等实际灰度图像方向场的计算结果。实验证明 ,这种方向场计算的时间可以与解析法相当。     

整体运动气体系统内粒子的最可几分布——兼对经典近似下若干问题的讨论

本文对整体运动气体系统内粒子的最可几分布作了推导,并对经典近似条件下若干问题进行了较为详细的讨论.     

基于切缝法求方向图的指纹奇异点定位

基于指纹识别技术中指纹奇异点定位在实现指纹分类和实现指纹识别的重要性，提出一种基于切缝法求方向图的奇异点定位算法，求出的方向图具有细节保留能力强、去噪能力强等特点．结合改进的Poincareindex法和切缝法求出的方向图在FVC2000指纹数据库上进行指纹奇异点定位，在时间复杂度和准确性上取得了较好的效果，可满足实际使用的需要．     

Forecasting the 10‐year US Treasury rate

This study compares the performance of two forecasting models of the 10‐year Treasury rate: a random walk (RW) model and an augmented‐autoregressive (A‐A) model which utilizes the information in the expected inflation rate. For 1993–2008, the RW and A‐A forecasts (with different lead times and forecast horizons) are generally unbiased and accurately predict directional change under symmetric loss. However, the A‐A forecasts outperform the RW, suggesting that the expected inflation rate (as a leading indicator) helps improve forecast accuracy. This finding is important since bond market efficiency implies that the RW forecasts are optimal and cannot be improved. Copyright © 2009 John Wiley & Sons, Ltd.     

Growth of decagonal quasicrystal phase in laser resolidified Al72Ni12Co16

An ultra-high temperature gradient directional solidification process produced by a widened laser beam was adopted to achieve the directionally solidified microstructure of the stable decagonal quasicrystal phase in Al72Ni12Co16 alloy. X-ray, SEM, TEM and optical microscopy techniques were used to investigate the microstructures and identify the phase. The directionally solidified decagonal quasicrystal showed the facet morphology and grew in lateral growth mode. The unusual periodic and quasiperiodic atomic structures of the decagonal quasicrystal and the epitaxial growth in the melt pool were considered to be the key factors influencing the growth morphology. The experimental results were consistent with the Toner's theoretical atomistic growth model.     

检查集成电路光刻掩模的实时白光信息处理系统

本文介绍一种用空间滤波检查集成电路光刻掩模的实时白光信息处理系统.采用该系统作检查比传统的镜检法或相干光学处理技术更为简便,且效果显著.借助这种技术能明显地察觉到掩模里的黑点、针孔、刻痕、电路损缺、短路或断路等微小缺陷.     

益阳民居概览

分析益阳自然环境的地方经济以及民族建设文化对当地民居的影响,逐步阐述益阳民居特色.