无线移动网络跨可信域的直接匿名证明方案?

基于信任委托的思想,提出一种移动环境下的跨可信域的直接匿名(direct anonymous attestation,简称DAA)证明方案,采用代理签名技术和直接匿名证明方法,实现对移动终端在多可信域之间漫游时的可信计算平台认证,并在认证过程中协商会话密钥,增强了远程证明体系的安全性。利用 Canetti-Krawczyk(CK)模型对方案的认证协议的认证安全性和匿名安全性进行了形式化分析和证明。分析表明,该方案能够抵抗平台伪装攻击和重放攻击,其性能适用于无线网络环境。     

基于新型三维辐射应力的近岸波流耦合模型

为了合理模拟近岸波流运动,基于考虑海底坡度影响的新型三维辐射应力公式,建立近岸三维波流耦合数学模型. 该模型引入2种波面水滚模式,考虑波浪附加水平紊动效应. 采用大量实测数据对所建模型进行验证. 结果表明,利用该模型可以较好地模拟近岸波浪传播以及增减水、沿岸流、底部离岸流、裂流等不同的近岸波生流现象. 该模型采用的波流耦合方式能够全面地反映近岸波流的相互作用,新型三维辐射应力公式较其他公式可以更准确地描述波生流的垂向结构. 对于不同的近岸流算例,获得更准确的模拟结果可能需要采用不同的水滚模式,说明更具普适性的水滚模型有待进一步的研究. 考虑波浪水平紊动会使模型计算出的流速平面分布更平滑,避免出现过于突兀的流场结果.     

3-甲氧基-4-苄氧基苯乙胺盐酸盐的合成

以香草醛为原料,先与溴苄合成苄醚,再与硝基甲烷缩合,经NaBH4/BF3.Et2O还原得相应的芳基乙胺,最后与氯化氢的乙酸乙酯溶液成盐,合成了目标产物3-甲氧基-4-苄氧基苯乙胺盐酸盐。考察了缩合反应的投料比、反应温度和反应时间,还原反应的还原剂用量和反应时间对反应收率的影响。优化后4步反应的总收率为79.4%,产品经ESI-MS和1HNMR确证了结构。     

基于PSCAD/EMTDC的风光互补并网发电系统建模与仿真

针对太阳能和风能的互补性,设计了一套风光互补并网发电系统。该系统是一套包括小型永磁直驱风力发电机、光伏阵列、具有最大功率点跟踪(MPPT)功能的Boost斩波换流器和定电压控制逆变器在内的完整、统一的风光互补并网发电系统仿真模型,针对西藏地区全年的实际太阳辐射情况和风况进行仿真分析,以模拟该地区风光互补系统的运行工况。仿真结果验证了风光互补系统应用于我国西部地区的可行性和有效性,具有重要的理论和现实意义。     

采用攻击策略图的实时警报综合分析方法

针对警报因果关联分析方法存在攻击场景图分裂且无法及时处理大规模警报的问题,提出并实现一种采用攻击策略图的实时警报综合分析方法．首先,通过在警报关联过程中引入推断警报环节避免攻击场景图的分裂;然后,采用一种新型滑动窗口机制,为每类攻击创建一个滑动窗口,并结合时间跨度与警报数量设定窗口大小,在保证关联效果基础上具有线性时间复杂度;最后,将该方法扩展为包含实时攻击场景重构、后续警报推测及分析结果融合的综合警报分析系统．实验结果证明了该方法的实际有效性和高效性．     

基于GRU的智能手机多场景步态认证

At present, most of the gait-based smartphone authentication researches focus on a single controlled scenario without considering the impact of multi-scenario changes on the authentication accuracy. The movement direction of the smartphone and the user changes in different scenarios, and the user’s gait data collected by the orientation-sensitive sensor will be biased accordingly. Therefore, it has become an urgent problem to provide a multi-scenario high-accuracy gait authentication method for smartphones. In addition, the selection of the model training algorithm determines the accuracy and efficiency of gait authentication. The current popular authentication model based on long short-term memory (LSTM) network can achieve high authentication accuracy, but it has many training parameters, large memory footprint, and the training efficiency needs to be improved. In order to solve the above problems a multi-scenario gait authentication scheme for smartphones based on Gate Recurrent Unit (GRU) was proposed. The gait signals were preliminarily denoised by wavelet transform, and the looped gait signals were segmented by an adaptive gait cycle segmentation algorithm. In order to meet the authentication requirements of multi-scenario, the coordinate system transformation method was used to perform direction-independent processing on the gait signals, so as to eliminate the influence of the orientation of the smartphone and the movement of the user on the authentication result. Besides, in order to achieve high-accuracy authentication and efficient model training, GRUs with different architectures and various optimization methods were used to train the gait model. The proposed scheme was experimentally analyzed on publicly available datasets PSR and ZJU-GaitAcc. Compared with the related schemes, the proposed scheme improves the authentication accuracy. Compared with the LSTM-based gait authentication model, the training efficiency of the proposed model is improved by about 20%. © 2022, Beijing Xintong Media Co., Ltd.. All rights reserved.     

基于信任评估的Ad Hoc网络关键节点选取算法

Ad Hoc网络中存在关键节点,它们的失效会严重影响网络性能。为了有效地选取重要且可信的关键节点,给出了关键节点的定义,提出了一种基于信任评估的关键节点选取算法。首先利用节点收缩法计算节点的重要度,然后结合D-S证据理论,建立节点的信任评估模型,通过该模型得到节点的客观信任值来判断节点的可信度,最后综合考虑节点的重要度和可信度来选取关键节点。仿真实验结果表明,通过该方法得到的关键节点失效后将造成网络性能急剧下降。