微腔中nc-Si/SiN超晶格的光致发光

研究了一维光子晶体微腔结构对nc-Si/a-SiNz超晶格发射的调制.一维光子晶体微腔采用两种具有不同折射率的非化学组分非晶氮化硅的周期调制结构,腔中嵌入采用激光晶化方法制备的硅量子点阵列,从Raman谱和透射电子显微镜分析得到其尺寸约为3～4 nm.从光致发光谱上观察到明显的选模作用、明显变窄的发光峰以及约两个量级的发光强度的增强.微腔对硅量子点阵列发光的调制主要表现在两个方面:共振模式的增强和非共振模式的抑制.硅量子点中位于腔共振模式的辐射跃迁被增强,非共振模式的辐射跃迁被抑制,因此位于腔共振频率处的跃迁通道成为硅量子点中唯一的辐射跃迁通道,导致光致发光谱的窄化和强度的增强.因此,在提高硅材料发光效率方面,光子晶体微腔具有非常大的应用前景.     

信息化建设中的信息安全风险评估

风险评估是发现薄弱环节的基本方法,不仅需在系统建设之前进行,更要贯彻在信息系统从设计到运行乃至到报废的整个生命周期之中。信息安全风险评估是建立信息安全体系的基础,是信息系统安全工程的一个关键组成部分。分析了国内外信息安全风险评估的现状,包括相关的评估标准体系、评估方法和评估过程,针对中国信息安全发展现状,探讨了目前信息安全风险评估工作中急需解决的问题。     

微腔中nc-Si/SiN超晶格的光致发光

研究了一维光子晶体微腔结构对nc-Si/a-SiNz超晶格发射的调制.一维光子晶体微腔采用两种具有不同折射率的非化学组分非晶氮化硅的周期调制结构,腔中嵌入采用激光晶化方法制备的硅量子点阵列,从Raman谱和透射电子显微镜分析得到其尺寸约为3～4 nm.从光致发光谱上观察到明显的选模作用、明显变窄的发光峰以及约两个量级的发光强度的增强.微腔对硅量子点阵列发光的调制主要表现在两个方面:共振模式的增强和非共振模式的抑制.硅量子点中位于腔共振模式的辐射跃迁被增强,非共振模式的辐射跃迁被抑制,因此位于腔共振频率处的跃迁通道成为硅量子点中唯一的辐射跃迁通道,导致光致发光谱的窄化和强度的增强.因此,在提高硅材料发光效率方面,光子晶体微腔具有非常大的应用前景.     

丙烷扩散火焰中多环芳烃的激光诱导荧光测量研究

以丙烷-空气扩散火焰为研究对象,联合激光诱导荧光与激光诱导炽光,在不同探测波长下,对火焰中多环芳烃(PAH)的二维分布进行测量,分析火焰中PAH荧光信号的分布特征。结果表明:在丙烷扩散火焰燃烧中,小环PAH逐渐变为大环PAH,随后形成碳烟;通过测量火焰不同位置处的荧光时间分辨信号发现,在相同的条件下,荧光波长越大,其对应的PAH环数越多,相对分子质量越大,荧光衰减时间越长;随着火焰高度位置升高,荧光信号的衰减时间受温度升高的影响呈下降趋势。     

悬锥鳃片在静态浑水中加速泥沙沉降的试验研究

对"加鳃"与"未加鳃"两装置中在静水中细颗粒泥沙沉降进行了试验,试验表明,悬锥鳃片在静态浑水中能起到加速泥沙沉降的作用.从试验现象及分析来看,"加鳃"装置在泥沙沉降过程中出现了四个不同斜率的曲线段,加速沉降的阶段可分为开始缓慢的前期加速沉降段和后期较快的全面加速沉降段.文章就此现象分析认为细颗粒泥沙在沉降过程中加快出现的絮凝作用是关键因素,其次泥沙的结构特性、水体的水质和形成了异重流等因素也有一定的影响.     

Error-space estimate method for generalized synergic target tracking

To improve the tracking accuracy and stability of an optic-electronic target tracking system, the concept of generalized synergic target and an algorithm named error-space estimate method is presented. In this algorithm, the motion of target is described by guide data and guide errors, and then the maneuver of the target is separated into guide data and guide errors to reduce the maneuver level. Then state estimate is implemented in target state-space and error-space respectively, and the prediction data of target position are acquired by synthesizing the filtering data from target state-space according to kinematic model and the prediction data from errorspace according to guide error model. Differing from typical multi-model method, the kinematic and guide error models work concurrently rather than switch between models. Experiment results show that the performance of the algorithm is better than Kalman filter and strong tracking filter at the same maneuver level. __________ Translated from Journal of University of Electronic Science and Technology of China, 2007, 36(2): 217–219 [译自: 电子科技大学学报]     

泉州传统建筑中气候性因素的当代表现

气候性因素是影响传统建筑形式的要素之一.对于泉州传统建筑而言,其气候性因素的表现有显著的特点,但在当代运用中又存在一些明显的缺陷.因此,借鉴当代地域性建筑设计中的气候性对策,分析并归纳出符合泉州当代建筑的气候性对策及其在建筑设计中的应用.     

泡沫玻璃在建筑外墙外保温中的应用现状及前景

通过对泡沫玻璃和2种常用建筑节能系统的比较,阐明了泡沫玻璃用于建筑节能的优势,分析了制约泡沫玻璃在建筑节能中应用的主要影响因素,探讨了推广泡沫玻璃在建筑节能领域应用的努力方向。     

Matching Trajectories of Anatomical Landmarks Under Viewpoint,Anthropometric and Temporal Transforms

An approach is presented to match imaged trajectories of anatomical landmarks (e.g. hands, shoulders and feet) using semantic correspondences between human bodies. These correspondences are used to provide geometric constraints for matching actions observed from different viewpoints and performed at different rates by actors of differing anthropometric proportions. The fact that the human body has approximate anthropometric proportion allows innovative use of the machinery of epipolar geometry to provide constraints for analyzing actions performed by people of different sizes, while ensuring that changes in viewpoint do not affect matching. In addition, for linear time warps, a novel measure, constructed only from image measurements of the locations of anatomical landmarks across time, is proposed to ensure that similar actions performed at different rates are accurately matched as well. An additional feature of this new measure is that two actions from cameras moving at constant (and possibly different) velocities can also be matched. Finally, we describe how dynamic time warping can be used in conjunction with the proposed measure to match actions in the presence of nonlinear time warps. We demonstrate the versatility of our algorithm in a number of challenging sequences and applications, and report quantitative evaluation of the matching approach presented.