2091合金的显微组织与氢脆敏感性

用动态充氢慢拉伸试验研究了氢对2091，合金力学性能的影响，用离子探针分析氢在合金中的行为，用透射电镜研究了合金显微组织与氢脆敏感性的关系，结果表明，充氢使合金抗拉强度，延伸率和断裂寿命明显降低，氢易于在晶界处偏聚和富集造成晶界弱化，晶界沉淀相种类，形态和分布是影响合金氢脆敏感性的主要因素。     

基于中国剩余定理的公钥加密方案同态性

针对现有(全)同态加密方案的整体性能不能达到实用要求的问题,为获得新的性能更好的同态加密思路,对基于中国剩余定理(CRT)的快速公钥加密方案的同态性进行了研究。考察了基于原方案构造加法和乘法同态操作的可能性,指出基于原方案不适于构造加法同态操作和乘法同态操作,并分析了原方案在安全性和效率方面存在的几个问题。提出了一个改进方案,分析了算法的安全性,尤其是对抗格基规约攻击的性能。研究了基于改进方案构造同态操作的可行性,并对原方案和改进方案的主要性能作了对比。最后对同态性构建过程中的经验进行了总结,提出了构建理想(全)同态加密方案的思路。     

8毫米波辐照鼠皮肤损伤观察及温升仿真

采用苏木精一伊红(HE)染色法对8毫米波辐照不同时间的小鼠皮肤组织切片染色.结果表明随着辐照时间的增加,组织损伤也在逐步加深.建立了考虑血流灌注和水分蒸发失热的一维生物热传导模型,数值计算得出动物表皮温升,计算结果与实验测定结果吻合较好.进一步计算得到了不同辐照时间,动物皮肤不同深度的温升.理论计算和实验相结合,得到了温度与组织损伤之间的关系,结果表明当组织温度上升约16℃时,可以引起组织形态的明显变化.     

Assessing and Evaluating the Scope and Constraints of Idylla Molecular Assays by Using Different Source Materials in Routine Diagnostic Settings

For cancer treatment, diagnostics concerning tumor type and determination of molecular markers in short TAT is critical. The fully automated, real-time PCR-based molecular diagnostic Idylla assays are well established in many laboratories for qualitative detection, short TAT and routine screening of clinically relevant oncogenic mutations. According to the manufacturer, all IVD assays are recommended for use only with FFPE tissue samples of 5–10 µM dissections with at least 10% tumor content. In this study, we tested the performance and accuracy of the IVD assays along with the gene fusion assay (RUO) with different tissue/source materials like isolated DNA/RNA, cryomaterial, etc. The study also included testing archival FFPE tissue sections dating back from 20 years and a performance check for different pan-cancer samples individually. All the assays tested with FFPE sections and gDNA/RNA input showed above 96% accuracy and sensitivity, individually with 100% specificity. The Idylla assays also performed exceptionally well on the archival FFPE tissues, and the use of assays for other solid tumors was also remarkable. The performance test and accuracy of Idylla assays showed high efficiency with certain limitations. For the use of Idylla assays, both qualitative and quantitative applicability of different tumor source materials could produce efficient results in different diagnostic settings within a short TAT.     

高炉铁水质量鲁棒正则化随机权神经网络建模

高炉炼铁过程运行优化与控制依赖于可靠、稳定的难测铁水质量(Molten iron quality, MIQ)指标模型.针对现有MIQ建模方法的不足, 本文提出一种新型的数据驱动鲁棒正则化随机权神经网络(Random vector functional-link networks, RVFLNs)算法, 用于实现MIQ指标在线估计的鲁棒建模.首先, 为了提高建模效率和降低计算复杂度, 采用数据驱动典型相关性分析方法从众多变量中提取与MIQ相关性最强的变量作为建模输入变量; 其次, 由于传统RVFLNs网络的输出权值由最小二乘估计获得, 易受离群数据影响而鲁棒性差, 引入基于Gaussian分布加权的M估计技术, 提出新型鲁棒RVFLNs算法建立多元MIQ指标的鲁棒模型; 同时, 在鲁棒加权后的最小二乘损失函数基础上, 进一步引入${L_1}$和${L_2}$两个正则化项以构成优化目标函数的Elastic net, 用于稀疏化RVFLNs网络的输出权值矩阵, 解决RVFLNs网络多重共线性和过拟合的问题.最后, 基于某大型高炉工业数据, 进行充分数据实验, 结果表明所提方法具有更高的建模与估计精度以及较强的鲁棒性能.     

高阶系统方法—Ⅱ.能控性与全驱性

本文首先简述了基于状态空间模型的一阶动态系统的能控性进展, 指出了一阶系统方法中卡尔曼能控性体系的一些问题.然后证明了线性定常系统能控的充要条件是它能化成一个高阶全驱系统, 同时还在一定程度上将这一结果推广到非线性系统的情形.基于这一发现, 本文定义了一般动态系统的完全能控性, 明确其意义在于存在控制律使得闭环系统为一线性定常的高阶系统, 并且可以任意配置闭环特征多项式的系数矩阵, 同时还指出其多方面相关结论.     

基于WLAHE的尘肺胸片图像增强方法

为提高X线胸片中尘肺病灶的易识别性,提出一种基于加权局部直方图均衡化(WLAHE)的尘肺胸片图像增强方法。采用WLAHE算法、局部直方图均衡化算法,以及直方图均衡化算法对0+期尘肺X线图像进行对比度增强处理,并对采用不同参数的处理效果进行比较。结果表明,WLAHE可在不引入过大噪声及不引起细节失真的条件下,采用更小的窗口,使0+期尘肺X线胸片上的病灶小阴影更突出。     

Dependence of the Time‐Space Structure of the Chemical‐Reaction Zone on the Initial Density of the Explosive

The results of a study of the chemicalreaction zone structure for a number of high explosives (HEs) are discussed. It is found that an increase in the initial density of the HEs leads to a structural change in the chemicalreaction zone involving elimination of the Von Neumann spike at the critical density point. Conversely, as the initial density of the explosive decreases, the ratios of the gasdynamic parameters (in particular, mass velocities) at the Von Neumann point to the same parameters at the Jouguet point increase. It is shown that to explain the indicated regularities, one does not need to invoke the assumption of an increasing contribution of the exothermic decomposition of the HE the shock. The results can be explained within the framework of classical Zeldovich–Von Neumann–Döring theory with an ordinary shock at the detonationwave front and, hence, with a nearly zero contribution to the total energy release in the chemical reaction zone.     

低温气体渗碳对304L奥氏体不锈钢抗氢性能的影响

对304L奥氏体不锈钢进行低温(470℃)气体渗碳,采用光学显微镜(OM),电子探针显微分析仪(EPMA)以及X射线应力分析仪(IXRD)研究了304L奥氏体不锈钢低温气体渗碳强化层的厚度、碳含量及残余应力分布。通过电化学充氢实验,结合X射线相结构分析(XRD),慢应变单轴拉伸试验,扫描电镜(SEM)观察以及氢含量检测等方法分析低温气体表面渗碳对304L不锈钢抗氢脆性能的影响。研究表明:304L不锈钢经30 h低温气体表面渗碳处理后,形成了约22μm的渗碳层,渗碳层中碳含量和残余应力在表面最高,分别为2%(质量分数)及-1.47 GPa,并沿深度方向梯度减小;低温气体表面渗碳大幅度提高304L不锈钢表面的稳定性,在充氢过程中不产生马氏体相变,从而提高其抗氢性能。此外,渗碳层中的压缩残余应力对抑制H扩散,也起到了积极的作用。     

Thermal precipitation or gelling behaviour of dissolved methylcellulose (MC) derivatives—Behaviour in water and influence on the extrusion of ceramic pastes. Part 1: Fundamentals of MC-derivatives

Methylcelluloses dissolved in water show a temperature dependent gelling behaviour. The gel temperatures depend mainly on the degree of substitution with methyl groups. The behaviour of methylcellulose containing pastes is of high importance in various applications. The paper describes the influence of the degree of substitution on the thermal characteristics of methylcelluloses in water and in ceramic pastes. The gelation temperature of the methylcellulose in both systems is increasing with decreasing degree of substitution. This enables a broader temperature window in the ceramic extrusion process. Extrusion near the gelation temperature normally leads to many defects in the extrudate. However, close to the gelation temperature the extruded profiles show more defects with methylcelluloses having a higher degree of substitution. Methylcelluloses having a low degree of substitution also enable a paste extrusion above the gelation temperature (up to 90 °C). This is not possible with currently commercially available methylcelluloses.