动态信号分析系统自动化校准方法研究

实现动态信号分析系统的自动化校准,需要分析处理的数据量极大,消耗计算机系统资源大且处理时间长。采用Lab View设计了一套自动化校准软件,可以有效缩短数据处理长度,提高处理速度。该软件分为数据采集模块和数据分析模块,被检动态信号分析系统连续采集标准信号源所发的信号,将采集数据保存为文本文件或电子表格文件,通过LAN将其载入数据分析模块。数据分析模块查找各校准点的初始有效索引,提取有效的校准数据段,然后采用逐段分析方法处理数据。将实验测试结果与采用常规方法的测试结果对比,该方法可以正确计算其频谱幅值线性误差、频谱幅值示值误差和幅频特性等参数,且需要的时间缩短为常规方法的40%,实现了动态信号分析系统的自动化校准。     

Preparation of stable polyurethane-polystyrene copolymer emulsions via RAFT polymerization process

Stable polyurethane-polystyrene (PU-PS) copolymer emulsions were prepared by the polymerization of 2-hydroxyethyl acrylate (HEA)-capped PU macromonomer and styrene, using azobis(isobutyronitrile) (AIBN), a radical initiator, and 4-((benzodithioyl)methyl)benzoic acid, a reversible addition-fragmentation chain transfer (RAFT) agent. As the molar ratio of the RAFT agent to AIBN increased, the zeta potential of the resulting copolymer emulsion increased, but the average size and size distribution of the emulsion droplets decreased. A living polymerization of HEA end-capped PU macromonomer and styrene was characterized by a linear increase in the molecular weight and decrease in the molecular weight distribution with consumption of monomers. The tensile strength, hardness and water-resistance of the copolymer films, prepared from the PU-PS copolymer emulsions, were much greater than those of the films prepared from the pure PU emulsion. The copolymer emulsions, prepared via the RAFT polymerization process, are expected to exhibit better storage stability than those prepared via the conventional free radical polymerization process, due to the presence of carboxyl groups derived from the RAFT agent at the PS block termini.     

Impacts of new technologies on media usage and social behaviour in domestic environments

Technological infrastructure at home is changing continuously and is becoming increasingly interconnected. Media devices, including the TV set, provide access to the Internet and offer manifold opportunities to consume media on demand. Additionally, personal devices, such as smartphones, also enable flexible consumption and sharing of media. Questions about how these technologies change the user's media usage and how these changes affect the social structure of a household, however, remain largely unanswered. In order to gain insight into the adoption of new technologies into daily routines, we explored these changes in respect of people's media usage in a qualitative long-term Living Lab study. We will present findings regarding personal routines, flexible integration of new devices into existing practices, influences on households as social systems and related issues in device access and collective use. We will highlight potentials and conflicts regarding device shifts and roles; restrictions in device access; social influences in the living room; and individual changes in media consumption.     

用金属卟啉络合物引发合成高分子量聚醚

介绍了用四苯基卟啉铝络合物催化体系合成高分子量聚醚的方法。该聚合过程显示出一种持续特性。产物具有均一的链长和极窄的分子量分布，且数均分子量Ｍｎ可通过改变单体与引发剂的摩尔比来控制。     

Living cationic random copolymerization of β-pinene and isobutylene with 1-phenylethyl chloride/TiCl4/Ti(OiPr)4/nBu4NCl

The first example of living cationic random copolymerization of β-pinene and isobutylene was achieved with 1-phenylethyl chloride/TiCl₄/Ti(OiPr)₄/nBu₄NCl (TiCl₄/Ti(OiPr)₄ mole ratio: 3/1) initiating system in CH₂Cl₂ at −40 °C. β-Pinene and isobutylene was consumed at almost the same rate, suggesting that the two monomers exhibit almost equal reactivity. At any monomer feed ratio, the number-average molecular weight (M_n) of the copolymers increased in direct proportion to the total monomer conversion, and the molecular weight distribution was relatively narrow (M_w/M_n=1.1-1.2) throughout the reaction. The reactivity ratios determined by the Kelen-Tüdõs method were rβ-pinene=1.1 and r_isobutylene=0.89, which indicated that the composition of copolymer is approximately identical to the monomer feed ratio. The analysis of the structure and sequence distribution of the copolymers by ¹H NMR spectroscopy further confirmed that perfectly random copolymers were obtained by this living cationic polymerization system. The glass transition temperatures of the copolymers obtained with varying monomer compositions were also determined by DSC method.     

Radical polymerization of butyl acrylate and random copolymerization of styrene and butyl acrylate and styrene and methyl methacrylate mediated by monospiro- and dispiropiperidinyl-N-oxyl radicals

Radical polymerization of butyl acrylate (BA) and random copolymerizations of styrene (St) and BA and St and methyl methacrylate (MMA) in the presence of 7-aza-15-hydroxydispiro[5.1.5.3]hexadecane-7-yloxyl (1) and 1-aza-2,2-dimethyl-4-hydroxyspiro[5.6]dodecane-1-yloxyl (2) were carried out. Radical polymerization of BA at 120 °C in the presence of 1 gave poly(BA) with M_n=20200 and M_w/M_n=1.30 at 23% conversion. The termination of polymerization observed around ∼20% conversion was solved to a certain extent by an addition of small amounts of dicumyl peroxide, and poly(BA) with M_n=37400 and M_w/M_n=1.33 was obtained in 46% yield. Random copolymerizations of St and BA and St and MMA in the presence of 1 and 2 at 80 °C gave the corresponding random copolymers with narrow polydispersities of 1.12-1.38 at the molar fraction above 0.30 of St in feed. The kinetic study for the NO-C bond homolysis of the corresponding alkoxyamines prepared from 1 and 2 were carried out, and evaluation of the preexponential factors (A_act) and the activation parameters (E_act) showed that the steric factors of the nitroxides are reflected mainly on E_act.     

利用置信规则库构建WSN节点故障检测模型

在无线传感器网络(wireless sensor network, WSN)节点故障检测领域的研究过程中,故障检测准确率会受节点数据的不确定性和专家知识模糊性的影响。针对这一问题,本文提出了一种基于置信规则库(belief rule base, BRB)的WSN节点故障检测方法。首先,根据WSN工作原理及节点工作特性描述WSN节点故障检测过程;然后,从空间和时间2个维度对节点数据提取特征,建立基于空间和时间相关性的WSN节点故障检测模型;最后,利用Intel Lab Data无线传感器数据集进行案例研究以验证模型的有效性。结果证明,本文方法能够统筹利用专家知识和节点数据实现WSN节点故障检测。     

以党的群众路线引领职工生活保障工作

群众路线是党的生命线和根本工作路线,在党的群众路线教育实践活动中,抓好职工生活保障工作,为民所思、所为,是落实党的群众路线具体体现。新形势下职工生活保障工作具有工作对象的群众性,工作原则的务实性,工作内容的多样性。因此,必须以党的群众路线引领职工生活保障工作,在谋划、推动、完善上下工夫,只有这样才能保证党的群众路线真正得到落实。     

浅淡关于平面设计的印刷色彩模式

可支持印刷的色彩模式有CMYK模式、灰度模式、位图模式和双色调模式。要提高印刷品的质量,掌握每种色彩模式的特点是关键。平面设计人员在处理图片时应先采用RGB模式处理图片的细微层次,然后再根据印刷品的实际情况谨慎转换成相应的印刷色彩模式。     

基于Web的虚拟物流实验室设计与实现

通过对虚拟物流实验室设计特点的分析,提出了基于Web的虚拟物流实验室构架,并设计了实现方案.运用3D 软件结合VRML建立虚拟场景模型,通过Java 3D对模型文件的调用实现虚拟场景的构建.调用Java 3D类库实现场景漫游、人机交互等功能,并对虚拟模型进行优化、重组.最后建立一个虚拟实验室的场景实例,验证了该设计方法具有良好的开发效率以及系统的沉浸性与交互性.