On the time-varying Halanay inequality with applications to stability analysis of time-delay systems

The main results of the paper are improvements on the stability analysis of Halanay inequalities with time-varying coefficients in both continuous-time and discrete-time setting. Three classes of improved conditions are established to ensure that the solution to the Halanay inequality is uniformly exponentially stable. The merit of the proposed new conditions is that the coefficients of the Halanay inequality can be unbounded and sign indefinite. This is achieved by using the notion and properties of uniformly asymptotic stable (UAS) functions. Based on the improved stability conditions for the Halanay inequality and the Lyapunov Razumikhin approach, three classes of sufficient conditions are established for testing the stability of time-varying time-delay systems. Finally, the advantages of the proposed methods are illustrated by some numerical examples with some of them borrowed from the literature.     

我国咨询产业人才培养模式的分析研究

本文介绍了国外咨询人才培养情况,分析我国咨询人员现状及存在的不足,从咨询人才培养环境、咨询人才培养机制、咨询人才引进机制这3个方面提出我国咨询人才培养模式,希望能够优化我国咨询产业咨询人才队伍建设.     

Visually constructing the chemical structure of a single molecule by scanning Raman picoscopy

The strong spatial confinement of a nanocavity plasmonic field has made it possible to visualize the inner structure of a single molecule and even to distinguish its vibrational modes in real space. With such ever-improved spatial resolution, it is anticipated that full vibrational imaging of a molecule could be achieved to reveal molecular structural details. Here we demonstrate full Raman images of individual vibrational modes at the ångström level for a single Mg-porphine molecule, revealing distinct characteristics of each vibrational mode in real space. Furthermore, by exploiting the underlying interference effect and Raman fingerprint database, we propose a new methodology for structural determination, which we have called ‘scanning Raman picoscopy’, to show how such ultrahigh-resolution spectromicroscopic vibrational images can be used to visually assemble the chemical structure of a single molecule through a simple Lego-like building process.     

CiteSpace软件应用研究的回顾与展望

CiteSpace信息可视化软件工具是由华人学者陈超美博士于2004年开发的,凭借其强大和先进的功能,该软件在国内外得到了广泛的应用和关注。国外对该软件的应用主要分布在信息科学、生命科学等领域,国内则主要应用于管理学和技术科学领域。从应用领域来看,主要包括图书情报学、管理学、科技政策、教育学以及具体的技术科学(纳米科学与技术、能源技术、新材料技术、电子信息技术等);从使用功能来看,主要是基于知识图谱的研究前沿与研究热点分析,科学计量学与引文分析,关键词共词网络分析,作者共被引与作者合作网络分析等。最后,针对当前的应用状况,本文对CiteSpace的应用前景和趋势进行了分析和展望。     

A hydrodynamic focusing microchannel based on micro-weir shear lift force

A novel microflow cytometer is proposed in which the particles are focused in the horizontal and vertical directions by means of the Saffman shear lift force generated within a micro-weir microchannel. The proposed device is fabricated on stress-relieved glass substrates and is characterized both numerically and experimentally using fluorescent particles with diameters of 5 μm and 10 μm, respectively. The numerical results show that the micro-weir structures confine the particle stream to the center of the microchannel without the need for a shear flow. Moreover, the experimental results show that the particles emerging from the micro-weir microchannel pass through the detection region in a one-by-one fashion. The focusing effect of the micro-weir microchannel is quantified by computing the normalized variance of the optical detection signal intensity. It is shown that the focusing performance of the micro-weir structure is equal to 99.76% and 99.57% for the 5-μm and 10-μm beads, respectively. Overall, the results presented in this study confirm that the proposed microcytometer enables the reliable sorting and counting of particles with different diameters.     

基于信息资源优化配置理论的信息共享策略研究

介绍信息资源优化配置理论,分析信息资源共享基础和发展战略,指出我国图书馆信息资源共享存在传统观念束缚、共享系统缺乏统一有效操作、资金经费投入不足、面临知识产权纠纷和信息安全等问题.提出提高认识、转变观念、开展图书馆信息共享创新服务,构建图书馆信息集群,构建多元化资金保障体系,加强图书馆信息共享系统的网络安全保障等对策.     

提高科技查新质量的方法研究

阐述了科技查新的定义,分析了科技查新工作存在的主要问题,提出了提高科技查新质量的方法。     

浅析高职院校通识教育课程的构建

通识教育到底是什么,每个人对此都有不同的认识,至今在学术界对通识教育还没有规范性的表述,对通识教育课程构建的重视程度远远不够。本文从通识教育课程的设置在高职院校面临的困难出发,阐述了通识教育课程体系的构建及通识教育课程的重要性。     

教育技术定义概览及相关问题的探讨

我国教育技术已经走过了几十年的历程,期间也经历一些波折。尤其是在八十年代之后学科发展进入了崭新的时期,出现了几次争论,主要是围绕学科定义展开的。从媒体技术和相关理论两个角度看教育技术定义的发展,对其在发展过程中的一些相关问题进行探讨。     

有机化学反应的实质和规律探讨——以醛酮化学反应为例

以醛酮化学反应为例。通过分析醛酮的各种反应,探讨有机化学反应的实质和规律,得出研究有机化学反应主要体现在两个方面:一是化合物或中间体的结构;二是反应的机理的结论。通过分析反应物或中间体的结构,从反应机理的高度探讨反应的实质,探索反应的内在规律。