足球比赛精彩场景的自动分析与提取

提出了基于MPEG压缩域音频流的足球比赛精彩场景自动分析与提取算法．首先直接提取出压缩域音频特征;然后基于提取出来的压缩域特征实现解说音的检测和分割,并且分别识别足球比赛中解说员激动解说和观众激昂欢呼两种类型音频事件;最后通过概率融合生成最终结果,融合结果所对应的比赛片段就是提取出的足球比赛精彩场景．实验结果表明了该算法的可行性．     

双层壳体防护结构抗高冲击可靠性研究

针对回收式弹载记录仪在硬着陆瞬间因高冲击会使记录仪扭曲变形而导致内部电路损坏失效的问题,提出了一种抗高冲击的双层壳体复合防护结构。结合先验数据模拟仿真记录仪硬着陆侵彻受力过程,确定垂直侵彻记录仪承受最大冲击过载,以此为基础设计落锤冲击试验研究双层防护壳体对高冲击过载能量传递的衰减特性。试验结果表明在瞬时冲击过载峰值小于25 000 g时,双层壳防护结构能有效衰减冲击能量,吸能效果可达50%,可以保护内部电路安全。     

基于XML 的震灾工程抢修方案形式化描述方法

为快捷、有效地形成一套描述规范统一、能在不同系统和平台间实现无障碍信息交换和应用的震灾工程抢修方案,采用XML实现震灾工程抢修方案的形式化描述。通过分析震灾工程抢修方案的组成要素,运用XML的方法对抢修方案进行结构化和形式化描述,在构建抢修方案类的基础上实现震灾工程抢修方案的形式化描述。结果表明:该方法具有很好的通用性和共享性,能准确有效地描述震灾工程抢修方案,对实际救灾抢险具有重要的意义。     

Photochemical synthesis and photocatalysis application of ZnS/amorphous carbon nanotubes composites

In this paper, a photochemical synthesis of ZnS-amorphous carbon nanotubes (ACNTs/ZnS) composites using ACNTs was reported, whose surface were modified with carboxylic groups as a support. The size and distribution of ZnS nanoparticles can be controlled by adjusting the initial amount of reactants and the reaction time. The ACNTs/ZnS nanocomposites were characterized by X-ray power diffraction, scanning electron microscopy and transmission electron microscopy. Studies showed that ACNTs/ZnS nanocomposites had high photocatalytic activity toward the photodegradation of dye molecule.     

Systematic experimental study on mechanical behavior of PVB (polyvinyl butyral) material under various loading conditions

The mechanical behavior of polyvinyl butyral (PVB) significantly influences crashworthiness and energy mitigation abilities of windshields in terms of pedestrian safety. In this article, mechanical characteristics of PVB are experimentally studied. First, tension and compression experiments on PVB specimen are carried out under various quasi‐static loading rates. Fundamental mechanism of rate‐dependent behavior is investigated. Besides, dynamic tension and compression experimental data are compared to investigate the mechanical behavior of PVB in a whole strain rate region and it is found that PVB behaves as a visco‐elastic material under compressive loadings in both quasi‐static and dynamic situations; however, in tension experiments, stress–strain curves of PVB under dynamic loadings are elasto‐plastic while those under quasi‐static loadings are visco‐elastic. Considering all the unique characteristics of PVB's behavior, constitutive models are then established based on Zhu‐Wang‐Tang model mathematically. Further, unit volume energy absorption of every experiment in quasi‐static tension and compression are calculated as well as the stress intensify factor. In addition, visco‐elasticity part in the constitutive model is employed. Results may offer useful experiment data and important constitutive characteristics of PVB material to further studies of automotive crashworthiness and pedestrian protection. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers     

承德避暑山庄古园林建筑群体概况

承德避暑山庄是我国现存规模最大、最富有特色的古代皇家园林，也是我国北方难得的自然风景区。它始建于清朝康熙四十二年，至乾隆五十五年建成，占地面积为五百六十四公顷，有近二十华里蜿蜒曲折的宫墙和一百一十九组建筑。其环境广阔，因境成景和山林野趣构成了承德避暑山庄园林建筑的基本特征。建筑选址和布局巧妙，造型活泼玲珑，体量及尺度适宜，色彩朴素淡雅，它兼有“宫”、“苑”的双重功能，是离宫型的园林。本文按照建筑特点及不同功能，将主要古建筑群体区分建筑名称、建筑年代、建筑位置、建筑形式、主要建筑物进行必要的说明和介绍。     

服装毛革铬鞣液循环使用研究

结合新型铬鞣交联剂的应用,探索出一种生产高质量服装毛革产品的铬鞣液循环利用技术,并探讨该技术中铬吸收对坯革收缩温度影响的主要因素,总结出可行的实施工艺。在铬鞣循环废液中铬粉耗用量为20g/L,铬交联剂用量为1.2g/L,使用自动提碱剂提碱时,坯革收缩温度能达到100℃以上,坯革的质量与常规铬鞣的坯革质量基本一致。     

基于深度加权法向映射的三维模型检索

提出一种基于深度加权法向映射的三维检索算法,从归一化处理后的物体形状出发,计算关于视点方向的深度加权表面法向统计分布,并将该分布沿视点方向作球面调和分析得到深度加权法向映射特征,通过比较该特征的距离来度量任意三维模型之间的相似性。