A systematic methodology for kinetic modeling of chemical reactions applied to n‐hexane hydroisomerization

Kinetic modeling provides chemical engineers with a unique opportunity to better understand reaction kinetics in general and the underlying chemistry in particular. How to systematically approach a modeling assignment in chemical reaction kinetics is typically less clear, especially for novices in the field. The proposed modeling methodology pursues an adequate compromise between statistical significance and physical meaning of the kinetic model and the corresponding parameters and typically results in models of an appropriate complexity. It comprises the following activities: (1) data analysis, aiming at qualitative information on the reaction mechanism and corresponding rate equations, (2) model regression to quantify this information via optimal parameter values, and (3) validation of the statistical significance and physical meaning of the parameter estimates. This methodology is successfully applied to n‐hexane hydroisomerization on a bifunctional catalyst. © 2014 American Institute of Chemical Engineers AIChE J, 61: 880–892, 2015     

基于FOABHC＿SVM的微电网短期负荷预测模型

为适应微电网的建设和发展对负荷预测效率及精度的要求,针对微电网负荷基数小、间歇性和随机性大等特点,提出一种基于历史认知果蝇优化算法（FOABHC）－优化支持向量机（SVM）的微电网短期负荷预测模型。以国内某微电网示范工程项目为例,将FOABHC＿SVM用于微电网短期负荷预测。实例仿真结果表明,所提出的FOABHC＿SVM预测模型优于SVM预测模型,更适用于当前微电网短期负荷预测需要。     

Design of High‐Mobility Diketopyrrolopyrrole‐Based π‐Conjugated Copolymers for Organic Thin‐Film Transistors

Since the report of the first diketopyrrolopyrrole (DPP)‐based polymer semiconductor, such polymers have received considerable attention as a promising candidate for high‐performance polymer semiconductors in organic thin‐film transistors (OTFTs). This Progress Report summarizes the advances in the molecular design of high‐mobility DPP‐based polymers reported in the last few years, especially focusing on the molecular design of these polymers in respect of tuning the backbone and side chains, and discussing the influences of structural modification of the backbone and side chains on the properties and device performance of corresponding DPP‐based polymers. This provides insights for the development of new and high‐mobility polymer semiconductors.     

Displacement Discontinuity or Complex Shape of Sample: Assessment of Accuracy and Adaptation of Local DIC Approach

In this paper, we study the impact of a complex shape of sample and the appearance of a displacement discontinuity on performances of measurement by local Digital Image Correlation (DIC). Both cases are modelled from synthetic images into two parts: one with a speckle field and another part without speckle or two parts with similar speckle fields but with different kinematics. The accuracy of displacement measurements assessed for DIC subsets crossing the boundary between the two parts is lower than the one obtained without discontinuity and justifies adapting DIC method. A new local DIC process is presented in detail. It is an alternative way able to take into account any shape of sample and several curved lines of discontinuity in the same subset. Two experimental examples are presented: displacement and strain fields obtained by DIC and adapted DIC are compared. We can conclude that it is possible to lead a mechanical analysis until the limits of the sample and even during the appearance and the propagation of a crack.     

基于PBAC模型和IBE的医疗数据访问控制方案

医疗卫生领域形成的医疗大数据中包含了大量的个人隐私信息,面临着外部攻击和内部泄密的潜在安全隐患。传统的访问控制模型没有考虑用户访问目的在侧重数据隐私的访问控制中的重要作用,现有的对称、非对称加密技术又都存在密钥管理、证书管理复杂的问题。针对这些问题,提出了综合应用PBAC模型和IBE加密技术的访问控制方案,支持针对医疗数据密文的灵活访问控制。通过加入条件目的概念对PBAC模型进行扩展,实现了对目的树的全覆盖;以病患ID、条件访问位和预期目的作为IBE身份公钥进行病患数据加密,只有通过认证并且访问目的符合预期的用户才能获得相应的私钥和加密数据,从而实现对病患信息的访问。实验结果证明,该方案达到了细粒度访问控制和隐私保护的目的,并具有较好的性能。