抵御已知/选择明文攻击的混沌图像加密算法

论文在对现有一类典型图像混沌加密算法的分析基础上,提出了一种改进的图像混沌加密算法。该算法引入小波变换,可以有效地克服一些混沌加密算法不能抵御已知/选择明文攻击的缺陷。     

MPTA型原油脱金属剂的工业应用

在对高金属含量原油进行初步评价的基础上，利用SH—Ⅰ型电脱盐试验仪对自主开发的MPTA型原油脱金属剂进行了原油脱金属的实验室研究。结果表明，当MPTA型脱金属剂加入量为250μg／g时，钙的脱除率可达97．4％，并且对其它金属元素，如镍、铁、钠、锰、铝和钒也有明显的脱除效果。该剂在山东恒源石油化工股份有限公司重交沥青车间500kt／a的电脱盐装置上进行原油脱金属工业试验的结果表明，经过二级电脱盐处理后，钙的脱除率达到99．1％，钠的脱除率为94．6％，铁的脱除率为82．9％，并可在一定程度上降低原油中镍和铜的含量。使用MPTA型原油脱金属剂显著降低了一、二级电脱盐装置的电场电流，有利于炼油厂的节能降耗。     

软锰矿氧化硫化钡制高纯碳酸锰和氢氧化钡工艺研究

软锰矿同硫化钡溶液在较低温度下进行氧化还原反应，当硫化钡含量控制在26-75g／L范围内，软锰矿与硫化钡的物质的量比为2．5-3，反应时间50-60min，软锰矿被硫化钡还原为MnO，其还原率可达93．5％以上；还原后的锰用硫酸浸取，溶液经除杂后，与碳酸铵反应而制成高纯碳酸锰。硫化钡则被氧化为氢氧化钡，经蒸发、结晶而制得入水氢氧化钡，其回收利用率高速95％。     

Wavelength and Waveband Assignment for Ring Networks Based on Parallel Multi‐granularity Hierarchical OADMs

In this paper we study the optimization issues of ring networks employing novel parallel multi‐granularity hierarchical optical add‐drop multiplexers (OADMs). In particular, we attempt to minimize the number of control elements for the off‐line case. We present an integer linear programming formulation to obtain the lower bound in optimization, and propose an efficient heuristic algorithm called global bandwidth resource assignment that is suitable for the design of large‐scale OADM networks.     

HDI工艺中取代涂树脂铜箔适合激光钻孔的半固化片

应用于HDI的激光钻孔半固化片的方法和其它常规材料相比具有的优缺点。     

Global stability of Internet congestion controllers with heterogeneous delays

In this paper, we study the problem of designing globally stable, scalable congestion control algorithms for the Internet. Prior work has primarily used linear stability as the criterion for such a design. Global stability has been studied only for single node, single source problems. Here, we obtain conditions for a general topology network accessed by sources with heterogeneous delays. We obtain a sufficient condition for global stability in terms of the increase/decrease parameters of the congestion control algorithm and the price functions used at the links.     

Fatigue crack growth in SiC particulates reinforced Al matrix graded composite

The SiC/Al graded composite was fabricated by powder metallurgy processing and its fatigue crack growth behavior was studied. The volume percentage of SiC particulates was distributed from 5 to 30% layer by layer on the cross section. Since the aluminium was dissolved together, there was no evident interface between the two layers with different volume fraction of SiC particulates. Fatigue crack growth was in direction of from 5 to 30% SiC layers under sinusoidal wave-form. The retardation of fatigue crack growth was found when crack propagated from low volume fraction of SiC to high volume fraction of SiC. The crack deflection and branching between two layers were observed, which decreased crack growth rates. In view of crack tip driving force, the plasticity mismatch between the layers shielded crack tip driving force, i.e. decreased the effective J-integral at the tip of the crack as the plastic zone of the crack tip spread from the weaker material into the stronger material.     

计费帐务系统发展趋势分析

计费帐务系统作为业务运营支撑系统的重要组成部分。其发展方向日益受到运营商的关注。通过对计量帐务系统的研究，首先介绍了传统计费模式的现状以及存在的问题，然后结合各大公司产品对计责帐务系统的关键技术进行了分析，最后提出未来计费帐务系统的特征及对其发展趋势的展望。     

一种基于空间到达角的卫星电子侦察信号分选方法

在建立简化的卫星电子侦察空间模型的基础上，提出了一种利用空间到达角分选卫星电子侦察信号的新方法。通过仿真实验验证了这种方法的可行性。该方法可用于密集信号的预处理。     

阜阳地区石炭-二叠系煤系烃源岩特征

阜阳地区石炭-二叠系煤系地层发育，但由于勘探程度较低，对该区煤系地层烃源岩的生烃潜力认识不清，严重制约了该区的油气勘探。在已有资料的基础上，通过有机地球化学和有机岩石学方法并结合模拟实验，探讨了该区煤系烃源岩的生烃潜力。研究结果表明阜阳地区石炭-二叠系煤系烃源岩有机质丰度达到中等-好烃源岩标准，有机质类型以腐殖型为主，盆地模拟结果显示阜阳地区石炭-二叠系煤系地层油资源量为（30.47~152.33）×10⁶t，气资源量为（266.7～1333.7）×10⁸m³，展示阜阳地区石炭-二叠系煤系地层具有较好的生油气潜力。