基于Schnorr数字签名和秘密分享的交换协议

通过在Schnlorr签名方案中利用秘密分享技术,给出了一种新的公平交易方案。该方案的公平性和安全性依赖于多个可信任第三方(TTP)。由协议的公平性和安全性分析可知,它比那些单纯地依赖于一个可信任第三方的公平交易方案具有更好的安全性和可靠性。     

改善高拱坝坝踵拉应力措施的探讨

目前改善高拱坝坝踵拉应力的措施,主要是坝体体型优化,以及设置诱导底缝。提出在拱坝上游地基内设置垂直缝的构想,重点分析了垂直缝设在不同高程范围和不同缝深对坝体应力和位移的影响。结果表明:设置垂直缝和诱导底缝都能够有效改善坝踵附近应力分布,对拱坝整体稳定影响较小。     

AKAIoTs: authenticated key agreement for Internet of Things

Wireless Networks - WSNs are one of the important components in the Internet of Things (IoTs), since they enable gathering and transmitting of data to the cloud server via the Internet medium....     

From mechanistic to kinetic analyses of ethanol steam reforming over Ir/CeO2 catalyst

This work presents a kinetic analysis of ethanol steam reforming (ESR) over a performing Ir/CeO₂ catalyst based on a bi-functional mechanism. A first conventional power-law based kinetic study was carried out by varying the main operating parameters (temperature, steam/ethanol molar ratio and partial pressure of products). A limited fit was achieved between the experimental data and the data calculated from this model based on a single type of site, demonstrating the need of a kinetic analysis integrating more closely the demonstrated bi-functional mechanism of the reaction. A kinetic model considering two distinct adsorption sites, on ceria support and on iridium particles, was then considered and only reactions involving the two types of sites, i.e. occurring at the ceria/metal interface, were used to build that model. A good agreement between the experimental data and the model was obtained, without systematic deviations. The central role of the metal-support interface was also consistent with the deactivation of this catalyst upon sintering, related to both changes in metal and support dispersion with time on stream.     

Hydrogen production from ethanol steam reforming in a micro-channel reactor

Ethanol steam reforming was studied over a supported Ir/CeO₂ catalyst in a micro-channel structured reactor. The catalyst coating was deposited on the channel walls and showed a remarkably high homogeneity and an excellent adherence to the stainless steel substrate, leading to stable performance during long-term runs. Hydrogen yields exceeding 40 L_H2 g_cat⁻¹ h⁻¹ were achieved during testing with partial ethanol conversion of 65% and a residence time in the order of a few milliseconds. This hydrogen productivity was found significantly higher than in a comparable conventional fixed-bed reactor hence being extremely promising for hydrogen production in micro fuel cell applications.     

基于CO2 减排目标的2050年全球能源需求展望

分析展望中长期能源需求,研究和提出相应的能源可持续发展战略,一直是国内外相关机构和学者研究的热点领域。应用时间序列、趋势外推、计量经济、能源系统（平衡）分析等模拟技术构建了全球能源需求分析模型。在此基础上,以2050年能源消费产生的CO2减排50%为目标设计了2 ℃情景,对该情景的能源需求进行了分析展望。研究显示：2 ℃情景下亚太地区特别是印度是全球能源需求增长的重要驱动力,全球一次能源需求总量将在2045年后趋近饱和;一次能源需求结构将实现由化石能源为主向非化石能源为主的转型,非水可再生能源快速发展是这一转型的主要动力;电能替代是终端能源消费结构变化的主旋律,电力将取代石油成为第一大终端用能。     

“移动互联网+智能用电”的机遇与挑战

移动互联网具备开放共享、随身便携、实名身份、地理定位等特点,正在迅速改变各个行业。移动互联网也深刻影响了智能用电产业的内外部环境,改变了用户行为习惯和体验要求,增强了用户、企业间的互动关系,促进了智能用电的移动化、实时化、互动化和个性化。从用户行为、营销方式、商业模式、产业生态、行业竞争等多个角度,分析了移动互联网对智能用电带来的机遇和挑战,并逐一有针对性地提出了策略建议。     

并联型有源电力滤波器的参数计算及仿真

提高电能质量的方法有很多,有源电力滤波器（APF）由于能够对谐波和无功电流进行快速、准确地补偿而被公认为消除电网污染、提高电能质量的有效方法。本文根据主电路拓扑结构,对相应的参数进行了计算,并结合MATLAB仿真软件对各参数进行了优化选择,最后根据文中的各个参数利用MATLAB仿真软件对APF进行了仿真。仿真结果表明,APF很好地实现了对负载输入电流的控制。     

利用随机投点法求可靠指标

基于可靠指标的几何涵义,运用随机投点法原理,提出了计算高度波动非线性功能函数的可靠指标和设计验算点的全局优化算法.该法避免了传统的可靠度分析方法(JC法)对高度波动非线性功能函数计算不收敛的麻烦,且该法不需要对功能函数求导,无需对非线性功能函数作线性化近似处理,从而提高了结构可靠度的计算精度,扩大了其适用范围,为结构可靠度分析提出了一种新的思路.最后通过实例证明了该方法的有效性和可操作性.     

柔性电缆插拨式快速终端和接头绝缘结构分析

用有限元法分析柔性电缆端部电场分布方法研究了有机复合材料界面压强与沿面放电电压的关系,探讨界面接触面压缩应力、压缩应变及橡胶材料蠕变、材料疲劳特征的规律。研究表明:柔性电缆终端和接头绝缘结构 应采用应力锥设计,选用三元乙丙橡胶作主要绝缘材料,其弹性和扯断永久变形应分别控制在50%和2%,插拔配 合的过盈值应在1.7～2.6之间。