曲坦类药物的制备方法综述

曲坦类化合物是一类重要的治疗偏头痛的药物,现已开发出来的有舒马曲坦,纳拉曲坦、佐米曲坦、利扎曲坦、阿莫曲坦、依利曲坦和氟伐曲坦.本文对其合成方法进行了分类介绍.     

阀门内漏单声波传感器监测方法研究

针对阀门内漏模拟和阀门内漏监测问题，提出了阀门内漏模拟和阀门内漏非介入式单声波传感器监测方法。设计了由法兰、薄纸片和带孔铝片组成的虚拟阀门，可真实地模拟阀门内漏瞬态过程，克服了传统阀门内漏模拟方法中存在的各种缺点。分析、比较了不同条件下阀门上下游声波传感器输出信号的频域特征，验证了阀门上游声波传感器设置的冗余性和基于单声波传感器实现阀门内漏监测的可行性。分析、比较了不同条件下单声波传感器输出信号的时频域特征，提出了基于峰值系数和小波包能量分率的阀门内漏时频域特征提取方法，并以阀门密封良好状态下的声波信号为样本，建立了基于SVDD的阀门内漏诊断模型。测试结果表明：本文提出的单声波传感器阀门内漏监测方法可行、模型诊断准确，且具有较强的抗干扰能力和较高的阀门内漏检测灵敏度。     

大学英语“翻转课堂”之实践与反思——以北京石油化工学院为例

近年来，国内学者对翻转课堂的相关研究主要集中在翻转课堂的阐述介绍和教学模式探究等方面，很少从实践的角度进行探究。笔者对北京石油化工学院的大学英语课程进行了翻转课堂教学实践,并针对出现的问题进行了反思和再实践；根据学生的英语水平和学习能力调整翻转课堂的实践模式，重新定位师生角色，有针对性地完善课前视频材料，摸索出了切实可行的翻转课堂实施步骤和学习模式。“翻转课堂”给大学英语教学带来了实效，提高了学生的英语综合应用能力。     

PTA尾气吸附系统的优化

针对吸附系统内除湿剂硅胶频繁破碎现象进行优化。在找出硅胶破碎原因的基础上,通过吸附塔直径放大18.3%,引出部分尾气,使床层流速降低。在吸附塔进口管处,安装雾沫分离器;在硅胶前沿填充部分耐水硅胶以减少液态水的冲击。再生蒸汽加热管上加调节阀防止硅胶过分干燥。使A塔硅胶使用了540d,B塔硅胶使用了630d。     

Stochastic stability of semi‐Markovian jump systems with mode‐dependent delays

Semi‐Markovian jump systems, due to the relaxed conditions on the stochastic process, and its transition rates are time varying, can be used to describe a larger class of dynamical systems than conventional full Markovian jump systems. In this paper, the problem of stochastic stability for a class of semi‐Markovian systems with mode‐dependent time‐variant delays is investigated. By Lyapunov function approach, together with a piecewise analysis method, a sufficient condition is proposed to guarantee the stochastic stability of the underlying systems. As more time‐delay information is used, our results are much less conservative than some existing ones in literature. Finally, two examples are given to show the effectiveness and advantages of the proposed techniques. Copyright © 2013 John Wiley & Sons, Ltd.     

A generalized robust H ∞ filtering for singular Markovian jump systems and its applications

In this paper, a generalized robust H _∞ filtering method is proposed for a class of singular Markovian jump systems, whose generality is mainly embodied that the desired filter could bear perturbances in terms of uncertainties on its parameter matrices. Firstly, an LMI condition of robust mode‐dependent filter is developed. Based on the given result, a new approach to mode‐independent H _∞ filter is presented, which establishes a direct connection between mode‐dependent and mode‐independent filters. Secondly, when the transition rate matrix is with elementwise bounded uncertainties or partially unknown, sufficient conditions of such robust mode‐dependent and mode‐independent filters are all developed within LMI frameworks. Finally, a numerical example is used to demonstrate the effectiveness of the proposed methods. Copyright © 2013 John Wiley & Sons, Ltd.     

影响有机硅热防护涂层的热导率的因素

以硅树脂为基料,配合中空玻璃微球等填料,制备了有机硅热防护涂层;研究了填料的组合、添加量、规格以及溶剂体系等对有机硅热防护涂层热导率的影响。结果表明,采用表面经过处理的中空玻璃微球和气相法白炭黑A380的组合填料、中空玻璃微球的用量选择60份、并使用酮类溶剂和芳香类溶剂的混合溶剂制成的热防护涂层,其热导率≤0·1W/(m·K),密度≤0·55g/cm3,拉伸强度≥2·0MPa。     

Non‐fragile H ∞ control for switched stochastic delay systems with application to water quality process

In this paper, the problem of non‐fragile observer‐based H _∞ control for discrete‐time switched delay systems is investigated. Both data missing and time delays are taken into account in the links from sensors to observers and from controllers to actuators. Because data missing satisfies the Bernoulli distribution, such problem is transformed into an H _∞ control problem for stochastic switched delay systems. Average dwell time approach is used to obtain sufficient conditions on the solvability of such problems. A numerical example and a real example for water quality control are provided to illustrate the effectiveness and potential applications of the proposed techniques. Copyright © 2013 John Wiley & Sons, Ltd.     

Fault detection for continuous‐time switched systems under asynchronous switching

In this paper, the problem of fault detection for continuous‐time switched systems under asynchronous switching is investigated. The designed fault detection filter is assumed to be asynchronous with the original systems. Attention is focused on designing a fault detection filter such that the estimation error between the residual and the fault is minimized in the sense of H _∞ norm. By employing piecewise Lyapunov function and average dwell time techniques, a sufficient condition for the existence of such a filter is exploited in terms of certain linear matrix inequalities. Finally, an example of a switched electrical circuit is provided to illustrate the effectiveness of the proposed approach. Copyright © 2013 John Wiley & Sons, Ltd.     

探讨数字化校园背景下的“微门户”建设构想--基于福建电力职业技术学院的数字化校园建设

该文分析了高职院校数字化校园建设的具体问题,借助“微门户”的概念,提出了数字化校园背景下的“微门户”建设构想,为高职院校数字化校园建设提供了一条有效的建设思路。