水利系统职工精神文化需求现状的对策与思考

随着物质生活水平的提高,水利职工精神文化需求不断增强。但在实际工作中存在着职工精神文化需求与水利大发展、大建设不相适应的地方,需要我们加强调查研究,从满足职工精神文化需求的视角出发,提出对策与思考。     

An effective splitting-and-recombination micromixer with self-rotated contact surface for wide Reynolds number range applications

It is difficult to mix two liquids on a microfluidic chip because the small dimensions and velocities effectively prevent the turbulence. This paper describes two 2-layer PDMS passive micromixers based on the concept of splitting and recombining the flow that exploits a self-rotated contact surface to increase the concentration gradients to obtain fast and efficient mixing. The designed micromixers were simulated and the mixing performance was assessed. The mixers have shown excellent mixing efficiency over a wide range of Reynolds number. The mixers were reasonably fabricated by multilayer soft lithography, and the experimental measurements were performed to qualify the mixing performance of the realized mixer. The results show that the mixing efficiency for one realized mixer is from 91.8% to 87.7% when the Reynolds number increases from 0.3 to 60, while the corresponding value for another mixer is from 89.4% to 72.9%. It is rather interesting that the main mechanism for the rapid mixing is from diffusion to chaotic advection when the flow rate increases, but the mixing efficiency has not obvious decline. The smart geometry of the mixers with total length of 10.25 mm makes it possible to be integrated with many microfluidic devices for various applications in μ-TAS and Lab-on-a-chip systems.     

Event-triggered non-fragile H∞ fault detection for discrete time-delayed nonlinear systems with channel fadings

In this paper, the event-triggered non-fragile H_∞ fault detection filter is designed for a class of discrete-time nonlinear systems subject to time-varying delays and channel fadings. The Lth Rice fading model is utilized to reflect the actual received measurement signals, and its channel coefficients own arbitrary probability density functions on interval [0,1]. The event-based filter is constructed to reduce unnecessary data transmissions in the communication channel, which only updates the measurement signal to the filter when the prespecified “event” is triggered. Multiplicative gain variations are utilized to describe the phenomenon of parameter variations in actual implementation of the filter. Based on Lyapunov stability theory, stochastic analysis technology along with linear matrix inequalities (LMIs) skills, sufficient conditions for the existence of the non-fragile fault detection filter are obtained which make the filtering error system stochastically stable and satisfy the H_∞ constraint. The gains of the filter can be calculated out by solving the feasible solution to a certain LMI. A simulation example is given to show the effectiveness of the proposed method.     

温州新兴制造业发展重点的选择及其战略

作为一个迫切需要加快工业化步伐的温州,如何在新世纪新阶段,以全球产业调整为背景,立足温州产业基础,从更宽泛的视野提出新兴制造业部门的培育和发展战略显得十分关键和紧迫。本文立足区域的经济发展现状充分分析了国内外背景,认为温州要清晰地把握目前制造业发展相对滞后的状况,结合“后发优势”,抓住国际技术进步加快、国际分工深化和制造业跨国转移的机遇,发展高技术附加和价值附加新兴制造业。研究发现,电子及通信设备制造业、医药制造业、交通运输设备制造业、电气机械及设备制造业、仪器仪表及文化、公用机械制造业等五大行业内的部分重要领域将是下阶段温州制造业发展的重点。就这些新兴重点领域文章分别提出了发展战略。     

浅谈图书开架借阅

本文结合作者的实践体会 ,论述了图书开架借阅的意义 ,分析了存在的问题 ,提出了搞好图书开架借阅的措施。     

情境教学在我国数学教育改革中的功用与反思

通过运用文献分析法,对情境教学在我国数学教育改革中的发展历程进行回顾与反思。我国的数学教学大纲/课程标准、核心素养,都与情境教学有着紧密的联系。数学教学中既强调情境认知,使抽象的数学具体化,也强调情感激发,在优化的情境中促使学生主动学习。情境教学在我国数学教育改革中的反思如下:(1)数学抽象性与情境教学研究的多样性兼容;(2)情境教学对学生情感、认知、能力的作用;(3)情境教学研究方法的转变。     

论高中生物学案的编制策略

学案式教学模式,通过改变学生以前学习的方式,追求教学过程中教和学的交流和互动,培养学生的爱提问题的习惯,让学生积极参与,寻找获得智慧的方法,发挥他们创新的能力,这是一种非常有效的教学模式。本文在参考以往学案教学经验的基础上,探讨了高中生物学学案的编写策略。