拉西瓦高拱坝岩体力学、工程地质研究成果综述

拉西瓦水电站高拱坝建基岩体工程地质、岩体力学研究是中国水电顾问集团2004年度专题科研成果之一“高混凝土拱坝建基岩体工程地质、岩体力学综合研究”的主要成果,其重点内容为岩体风化、卸荷、岩体质量级别的定量划分、河谷应力场分带、建基岩体主要岩体力学参数研究,坝肩抗滑稳定、开挖后综合检测验证等;在理论探讨、方法实践、预测验证和创新尝试等方面取得了一定成果,具有一定的社会、经济效益。     

高温合金材料在铝电解工业中的应用探讨

对高温合金在铝电解工业用作惰性金属阳极材料的选择进行阐述，并就实际应用过程中的抗氧化耐腐蚀性进行探讨；阐述适用于铝电解工业的惰性阳极合金所应具备的必要条件和必须解决的问题，并介绍目前有关的研究动态和研究方向。     

紧凑 Tokamak(球形环)聚变堆第一壁及中心导体柱上中子负荷及核热计算与分析

采用通用蒙特卡罗粒子输运程序ＭＣＮＰ／３８计算低环径比Ｔｏｋａｍａｋ（紧凑环或球形环）聚变堆第一壁及中心导体上的中子壁负荷分布和核热沉积分布，并与常规Ｔｏｋａｍａｋ堆第一壁上中子壁负荷分布和核热沉积分布进行比较、分析。结果表明，在中子壁负荷归一化为１ＭＷ／ｍ２时，与常规Ｔｏｋａｍａｋ相比，在低环径比Ｔｏｋａｍａｋ堆第一壁及中心柱表面上中子壁负荷分布峰值并不比常规Ｔｏｋａｍａｋ堆第一壁上的峰值高，而且低于低环径比Ｔｏｋａｍａｋ堆整个第一壁上的平均值，而中心柱上的核热沉积峰值稍高于常规Ｔｏｋａｍａｋ堆第一壁上的核热沉积峰值，但对较高中子壁负荷情况，中心导体柱上的核热沉积和辐照损伤仍可能是比较严重和值得特别研究的问题。     

螺栓联接法兰瞬态温度场分析

建立了螺栓法兰联接的三维力学及传热学模型,在考虑垫片非线性基础上,研究了法兰的瞬态温度场分布以及温度场的变化,对垫片和螺栓载荷的影响.研究表明,由于瞬态温度场的影响,螺栓载荷变化滞后于垫片载荷的变化,并且随着内壁温度的升高而增加;垫片外侧载荷变化呈先升后降的规律.     

Real-time homogenous translucent material editing

This paper presents a novel method for real-time homogenous translucent material editing under fixed illumination. We consider the complete analytic BSSRDF model proposed by Jensen et al. [ [JMLH01] ], including both multiple scattering and single scattering. Our method allows the user to adjust the analytic parameters of BSSRDF and provides high-quality, real-time rendering feedback. Inspired by recently developed Precomputed Radiance Transfer (PRT) techniques, we approximate both the multiple scattering diffuse reflectance function and the single scattering exponential attenuation function in the analytic model using basis functions, so that re-computing the outgoing radiance at each vertex as parameters change reduces to simple dot products. In addition, using a non-uniform piecewise polynomial basis, we are able to achieve smaller approximation error than using bases adopted in previous PRT-based works, such as spherical harmonics and wavelets. Using hardware acceleration, we demonstrate that our system generates images comparable to [ [JMLH01] ]at real-time frame-rates.     

Parasitic Bipolar Junction Transistors in a Floating-Gate MOSFET for Fluorescence Detection

In this letter, we examined whether the parasitic bipolar junction transistors (BJTs) in the MOSFET fabricated by the standard CMOS process can play a role as a fluorescence detector. To suppress the action of two vertical parasitic BJTs, the gate and n-well were tied in the parasitic BJTs, and the body node was connected to the drain. The proposed device was compared with the inherent and the parasitic diodes in the MOSFET. It had 100 times higher photocurrents than the diodes in the MOSFET. In addition, it was applied for the detection of the fluorescent signal, and could detect near 10 nM of Alexa 546. Therefore, CMOS-process-compatible parasitic BJTs can be used as a photodetector in an integrated fluorescence detector.     

Preparations of nanosized TiO2 in reverse microemulsion and their photocatalytic activity

Nanosized titania sol has been produced by the controlled hydrolysis of titanium tetraisopropoxide (TTIP) in sodium bis(2-ethylhexyl)sulfosuccinate (AOT) reverse micelles. The physical properties, such as surface area, crystallite size and crystallinity according to R and W₀ ratio, have been investigated by TEM, XRD, BET, FT–IR, TGA and DTA. In addition, the photocatalytic decomposition of p-nitrophenol has been studied by using a batch reactor in the presence of UV light in order to compare the photocatalytic activity of prepared nanosized titania. It is shown that the anatase structure appears in the 300–600 °C calcination temperature range and the transformation of anatase into rutile starts above 700 °C. The crystallite size increases with increasing R and W₀ ratio but W₀ ratio shows a stronger effect on the crystallite size than R ratio. In the photocatalytic decomposition of p-nitrophenol, the photocatalytic activity is mainly determined by the crystallinity of titania. In addition, the titania calcined at 500 °C shows the highest activity on the photocatalytic decomposition of p-nitrophenol() and the pure anatase structure.     

光催化降解废气过程中紫外辐射照度模拟和优化

为在光催化设计中合理布置紫外灯,减少光在传输过程中的损失,概括总结径向辐射模型、多点源叠加近似辐射模型和离散坐标辐射模型等3种经典的紫外辐射物理模型;基于离散坐标辐射模型模拟某公司生产的光催化氧化废气处理装置的紫外辐射照度;通过调整灯管布置距离改变光强分布,并拟合光催化单元和光催化网表面的平均紫外辐射照度随灯管布置距离变化曲线.结果表明,距离参数在55～65 mm时,该光催化反应装置的光能利用率较好;紫外灯的合理布置可有效提高光能利用率.     

基于YCbCr肤色模型改进算法及区域特征的人脸检测研究

针对当前人脸检测的研究现状与难题,采用改进的YCbCr椭圆聚类肤色模型进行肤色区域提取,根据肤色在YCb’Cr’空间的分布,对于亮度小于80的非肤色像素点会误判为肤色点,则缩小椭圆聚类;对于亮度大于230的肤色像素点会误判为非肤色点,则扩大椭圆聚类,有效避免了在高亮度区域和亮度较低的区域中的肤色点误判问题。接着利用人脸的几何特征,对二值化图中的目标区域进行比例、大小结构的分析,排除不可能的人脸区域,并基于肤色和位置进行区域优化,将处理后的结果作为候选人脸区域输出。