Synthesis of Diamond@SiO2@Ag composite materials for high SERS effect

Among various carbon materials, diamond stands out due to excellent physical and chemical properties. In this work, we designed Dia@SiO₂@Ag composites combining diamond micropowder and Ag nanoparticles by a simple chemical method and obtained stable substrate for surface enhanced Raman scattering (SERS) owing to its high surface-to-volume ratio, low density, as well as close bond between diamond and Ag. As-prepared Dia@SiO₂@Ag presented high activity to detect crystal violet and rhodamine 6G molecules, which was demonstrated by significantly enhanced SERS spectra and high enhancement factor values (10⁸-10⁹). Moreover, Dia@SiO₂@Ag also showed desired sensitivity, which was investigated by detection limit. Therefore, our study provided more theoretical support and broadened the functional applications of diamond, particularly in Raman detection.     

单麦克风和双麦克风语音增强系统的研究

本文对采用减谱法和箱关法的语音增强系统进行了研究，系统的噪声为白噪声和普通机房噪声。减谱法采用单麦克风输入，试验中发现语音的分帧方法对消噪影响很大，通过比较得到了一种具有明显消噪效果的分帧方法，在相关法中采用双麦克风输入，对两个输入信号之间的时延差进行了补偿，在求维纳滤波器系数时，对信号谱进行统计平均，从而使消噪后的语音信号具有较好的自然度。在研究以上两种方法的基础上，我们提出了一种混合消噪系统，     

Oxygen transport rate on Rhodococcus erythropolis cultures: Effect on growth and BDS capability

The influence of oxygen transport rate on Rhodococcus erythropolis cultures has been studied in a stirred tank bioreactor under different transport and uptake conditions. Oxygen uptake rate has been measured by applying a modified dynamic method and a kinetic model is proposed, obtaining the kinetic parameter values: specific maintenance and yield coefficients. The volumetric mass transfer coefficients under inert conditions, k_La, and during the bioprocess, K_La, have been determined. The values obtained are different and a biological enhancement factor E, has been considered. These parameters have been predicted by the theoretical model and good agreement with experimental data under the conditions studied has been found. The oxygen limitation has been expressed by a modified dimensionless Damköhler number, Da, the relationship between transport and biological reaction rates. This number decreases with increasing stirrer speed; that is, when mass transport resistance decreases. The efficiency of oxygen utilization can be determined by a film effectiveness factor, η. The effectiveness factor was found to be a strong function of Damköhler number and decrease with increasing Da. Furthermore, oxygen concentration into culture depends on the mass transfer and consumption rates. The theoretical model proposed is able to reasonably predict the evolution of dissolved oxygen concentration with time of cultivation.     

管内覆丝网强化对流换热及阻力特性的实验研究

通过实验对管内覆丝网管进行了强迫对流换热和阻力特性研究。结果表明：管内覆丝网使换热明显增强，阻力也相应增长。菱形丝网对角线距离与平行边距离之比对换热效果有决定作用，丝网厚度对换热的影响比较小，而丝网网格的大小对换热几乎没有影响，在相同的泵功率和几何条件下，换热系数最大增加２１％。     

Accurate Depth of Field Simulation in Real Time

We present a new post processing method of simulating depth of field based on accurate calculations of circles of confusion. Compared to previous work, our method derives actual scene depth information directly from the existing depth buffer, requires no specialized rendering passes, and allows easy integration into existing rendering applications. Our implementation uses an adaptive, two‐pass filter, producing a high quality depth of field effect that can be executed entirely on the GPU, taking advantage of the parallelism of modern graphics cards and permitting real time performance when applied to large numbers of pixels.     

Learning Natural Colors for Image Recoloring

We present a data‐driven method for automatically recoloring a photo to enhance its appearance or change a viewer's emotional response to it. A compact representation called a RegionNet summarizes color and geometric features of image regions, and geometric relationships between them. Correlations between color property distributions and geometric features of regions are learned from a database of well‐colored photos. A probabilistic factor graph model is used to summarize distributions of color properties and generate an overall probability distribution for color suggestions. Given a new input image, we can generate multiple recolored results which unlike previous automatic results, are both natural and artistic, and compatible with their spatial arrangements.     

黑色冶金材料领域中化工冶金研究所前期工作的回顾

系统地回顾了从建国到90年代初,化冶所为重工业和矿物资源综合利用所做的科研工作、取得的结果和成绩的概况．其中一些研究结果已经在国内得到广泛使用,一些结果为我国新技术的开发奠定了基础．     

基于孤立像素点去除的车牌ROI区域快速定位方法研究

车牌识别（LPR）作为当前较为广泛研究的热门课题之一,已经日趋成熟和完善,但传统车牌提取算法中仍然存在对单个像素点过分依赖、识别率不高等问题。提出一种基于孤立像素点去除的车牌感兴趣区域提取方法,在Sobel算子边缘检测算法的基础上,采用基于行列比例和周围相似度两种方法,对单像素点进行处理,有效去除影响感兴趣区域中的孤立点,突出车牌特征并提高识别精度。实验结果表明,该方法较传统方法识别速率平均提高约5%,识别精度平均提高约15%。     

卡尔曼滤波语音增强算法的CUDA实现

提出一种卡尔曼滤波语音增强算法的统一计算设备架构并行实现方案。该方案通过离散余弦变换把含噪语音分解为不相关的DCT系数,使原来的时域串行处理转化为统一计算设备架构并行处理,只需较少的线性预测阶数,节省运算时间。实验结果表明:与时域卡尔曼滤波比较,该方法有更高的输出分段信噪比,其统一计算设备架构加速方案可有效缩短语音增强运算的时间。