Spatial reasoning about multimedia document for a profile based adaptation

The continuous evolution of smart devices has led to serious limitations in multimedia applications. The multimedia graphic design and animation and the increased use of rich and complex multimedia content on the web or other media have all created a need to diversify the accessibility of the content. Therefore several techniques are used today to design a universally accessible content. The main techniques that are still used to maintain accessibility is to create two parallel streams of design and development of the same content. Thus, the continuous evolution will certainly lead to create other streams. For this, the automatic reasoning on multimedia to allow a computer to modify the design according to different variables, devices capabilities, user status and context to provide personalized adapted content. In this paper, we propose an abstract document model called XMS short for XML Multimedia Specification; it describes the composition of an original multimedia document and can be extended to any document type. We present how we may use spatial information present in this document to adapt and modify the original document. We mainly focus on the spatial aspect of a web document, a combination of RCC8, qualitative distances, and directions are used to describe the layout of a set of objects. The level of granularity of the definition of the objects defines the level of details that will be processed by our PROLOG based inference system, simplified versions of algorithms from the inference system and how it works on the spatial dimension of the document are shown. In the end samples of how spatial relations manipulation algorithms work are illustrated.     

Effect of antifoam agents on bubble characteristics in bubble columns based on acoustic sound measurements

In this paper, the effect of antifoam agents on bubble characteristics in bubble columns is studied. Specifically, the bubble characteristics of air in tap water are compared to those of air in 5% and 10% antifoam solutions. Bubble characteristics such as gas holdup, bubble diameter, bubble-size distribution, and damping ratio were investigated at various superficial gas velocities. These properties were deduced from the acoustic sound measurement. The study revealed that the addition of antifoam chemicals reduces the overall gas holdup and increases the average bubble diameter. The bubble-size distribution in tap water is found to be homogeneous while in antifoam solutions to be heterogeneous. It is also found that at low gas velocities the damping ratio for antifoam solutions is higher than that for tap water, while at high gas velocities the damping ratio is not affected. The results affirm that acoustic probes are excellent measuring tools over classical tools at moderate gas velocities.     

不同水泥掺量胶结钙质砂的导热性能及微观结构分析

钙质砂的导热性能影响周围土体的传热过程,引起不同环境温度下钙质砂的工程力学性能变化及灾害效应。基于热针法分析5种不同水泥掺量（P_s=5%、7.5%、10%、12.5%、15%）胶结钙质砂的导热系数变化规律,利用SEM、MIP、NMR技术综合揭示该过程中胶结钙质砂微观孔隙结构变化的本质特征,在此基础上阐释热特性演化的微观机理。试验结果表明：胶结钙质砂的导热系数λ随水泥掺量P_s的增大而递增,P_s小于10%时,λ呈线性递增,P_s大于10%时,λ增长缓慢;随着水泥掺量P_s的增大,胶结钙质砂中孔隙数量越来越少,孔隙占比下降明显,但P_s增大到10%后,总孔隙面积、孔隙数量、孔隙率等微孔隙结构参数变化减缓;不同水泥掺量胶结钙质砂的导热系数λ与其微观孔隙结构变化呈负相关关系,本质原因在于凝胶状的水泥水化产物连续填充了胶结钙质砂孔隙,降低了其孔隙率,改善了砂样内部传热,宏观表现为其导热系数λ随水泥掺量P_s的增大而增大。     

980MPa高强钢焊接接头薄弱环节的确定

通过在低温下进行拉伸试验、冲击试验以及扫描电镜下的断口观察,对屈服强度为980 MPa新型高强钢的MAG和TIG焊接接头的性能和断裂机理进行了研究,并在此基础上确定焊接接头的薄弱环节,提出其薄弱环节对接头整体性能的影响规律.结果表明,这两种焊接方法焊缝金属的抗拉强度与母材相差不大,但其断面收缩率有所降低;焊缝金属尤其原...     

Gelatin controversies in food,pharmaceuticals, and personal care products: Authentication methods,current status,and future challenges

Gelatin is a highly purified animal protein of pig, cow, and fish origins and is extensively used in food, pharmaceuticals, and personal care products. However, the acceptability of gelatin products greatly depends on the animal sources of the gelatin. Porcine and bovine gelatins have attractive features but limited acceptance because of religious prohibitions and potential zoonotic threats, whereas fish gelatin is welcomed in all religions and cultures. Thus, source authentication is a must for gelatin products but it is greatly challenging due to the breakdown of both protein and DNA biomarkers in processed gelatins. Therefore, several methods have been proposed for gelatin identification, but a comprehensive and systematic document that includes all of the techniques does not exist. This up-to-date review addresses this research gap and presents, in an accessible format, the major gelatin source authentication techniques, which are primarily nucleic acid and protein based. Instead of presenting these methods in paragraph form which needs much attention in reading, the major methods are schematically depicted, and their comparative features are tabulated. Future technologies are forecasted, and challenges are outlined. Overall, this review paper has the merit to serve as a reference guide for the production and application of gelatin in academia and industry and will act as a platform for the development of improved methods for gelatin authentication.     

基于双向渐进结构优化方法的双螺杆榨油机榨笼优化设计

双螺杆榨油机中榨笼作为压榨部分的关键部件,其对榨膛内挤油压力的形成和对两根螺旋轴的支撑起到关键作用。针对目前传统经验设计的榨笼尺寸和质量偏大,造成制造材料浪费的问题,将双向渐进结构优化方法(Bi-Directional Evolutionary Structural Optimization,BESO)应用到榨笼的设计中。以榨笼的刚度最大化为目标,以体积为约束条件,在Abaqus环境下,采用Python程序实现BESO优化算法,设计出新的榨笼结构。通过优化设计前后的对比分析表明,新的结构在满足强度要求的条件下,质量减少了35.1%。该优化分析方法为后续的榨笼设计提供了一种新思路。     

基于局部基底弯曲法的高灵敏度薄膜应力测试技术

针对MEMS(micro-electro-mechanical system)和NEMS(nano-electro-mechanical system)对薄膜应力测试的要求,开发了一种新型高灵敏度薄膜应力测试技术,使用自行搭建的准纳米光学干涉测试系统,利用局部基底弯曲来检测薄膜的内应力.该方法不仅保留了传统基底弯曲法的所有优点,而且消除了其系统误差.使用ANSYS对测试结构进行了模拟和优化,对于30nm厚的薄膜,应力检测的分辨率为1.5MPa,优于目前国际上的相关报道.本测试结构使用各向异性腐蚀和DRIE(deep reactive ion etching)完成,加工工艺简单实用.文中使用该测试技术对常用MEMS薄膜的残余应力进行了测量,结果与其他测试方法得到的结果基本一致,测量重复性优于1%.该技术可以用于测试纳米级薄膜及超低应力薄膜的内应力.     

Structure,electrical, dielectric,and optical investigation on polyvinyl alcohol/metal chloride nanocomposites

Different concentrations of metal chlorides/polyvinyl alcohol nanocomposites have been prepared by the typical solvent cast technique. The prepared samples were investigated by different techniques such as X‐ray diffraction, differential scanning calorimetry, and scanning electron microscope. DC and AC conductivities are examined at different temperatures and frequencies. An activation process was found in the DC conductivity versus temperature relation and the activation energy was calculated. The AC conductivity obeyed the ω^S power law. The behavior of S with temperature was studied. Various dielectric parameters such as dielectric constant (ε′), dielectric loss (ε″) and loss tangent (tan δ) have been determined in the temperature range 303–443 K at different frequencies. The dielectric parameters were found to decrease with increasing frequency. The study of dielectric relaxation as a function of temperature at constant frequency shows two relaxation mechanisms. The optical band gaps and band tails were estimated from the measured absorption spectra. The applied photon energy found to affect the observed optical band gaps. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

智能电网需求侧用户参与度研究模型

为充分挖掘智能电网需求侧与用户参与度的响应能力,探究电网需求侧的用电负荷影响,建立了智能电网需求侧用户参与度研究模型。采用聚类算法在噪声、模糊数据中提取特征数据,并对其进行归一化处理。根据智能电网的调配用电需求量,构建收益函数模型;将用户群体划分结果与博弈论相结合,建立不同类型用户博弈论模型,并组建电网需求侧用户参与度研究模型,定义电价收益、价格响应、智能调配用电时间等参数,为智能电网参与市场环境下的用户参与度调控提供了模型支持。以河北电网为测试对象进行测试,结果表明：随着时间的增加以及电价的降低,用户参与比例为89%,用户满意度均值为90%。智能电网需求侧的响应特性受用户参与度的影响,所提模型可以准确完成智能电网需求侧下的用户参与度计算,确保电网需求侧电力市场的供需平衡。