MC55模块在电力负荷管理终端中的应用

文章设计了基于MC55的电力负荷管理终端,包括无线通信模块与负荷管理终端接口的硬件设计、数据传输软件的设计和防止无线链路掉线维持链路的实时在线方法。基于该种无线通信的电力负荷管理系统,具有扩充性强、可靠性高、传输速率快、实时性强等优点。GPRS网络为电力自动化系统提供了一种高可靠、易扩展和便于维护的通信方式。     

增强玻璃纤维对MC尼龙复合材料摩擦学性能的影响

在ＭＭ－２００型磨损试验机上,研究了玻璃纤维增强ＭＣ尼龙（ＧＦ／ＭＣ）复合材料的干摩擦磨损特性,借助于扫描电镜探讨了它的磨损机理,并与ＭＣ尼龙作了对比。结果表明,在给定的试验条件下,随载荷和滑动速度的增大,二者的摩擦温度升高,ＭＣ尼龙的摩擦系数减小,ＧＦ／ＭＣ的摩擦系数先增后减出现一最大值;当ＰＶ值低于８４Ｎｍ／ｓ时,ＧＦ／ＭＣ材料的摩擦系数和磨损率比ＭＣ尼龙小,磨损机理均以粘着磨损和磨粒磨损为主,但ＧＦ／ＭＣ的粘着磨损比ＭＣ尼龙轻;当ＰＶ值大于８４Ｎｍ／ｓ时,ＧＦ／ＭＣ的摩擦系数略大于ＭＣ尼龙,而磨损率则显著高于ＭＣ尼龙,其磨损机理主要为疲劳剥落和磨粒磨损,而ＭＣ尼龙的磨损机理主要为粘着磨损和磨粒磨损。     

水性光油的组成分析

利用薄层色谱、ＩＲ、１Ｈ－核磁共振、１３Ｃ－核磁共振、及裂解气相色谱／质谱等技术对未知水性光油进行了测定和分析，得到了光油的组成和配比，并确定了其组成的化学结构     

基于ST7FMC的永磁无刷直流电机控制系统研究

介绍了一种基于ST7MC专用电机控制芯片的电动车无刷直流电机控制系统，详细介绍了控制器的硬件、软件设计方案，分析并对比了有、无传感器的电机控制技术．实验证明，系统控制效果良好，硬件设计具有高性价比、     

IrDA数据传输式智能监控器

介绍应用于高压变电场所，采用ＭＣ６８ＨＣ１６Ｚ１ＭＣＵ设计的ＩｒＤＡ数据传输式智能监控器，给出了硬件和软件设计，说明了电磁干扰的防护方法。     

Adsorption of DNA onto anionic lipid surfaces

Currently self-assembled DNA delivery systems composed of DNA multivalent cations and anionic lipids are considered to be promising tools for gene therapy. These systems become an alternative to traditional cationic lipid–DNA complexes because of their low cytotoxicity lipids. However, currently these nonviral gene delivery methods exhibit low transfection efficiencies. This feature is in large part due to the poorly understood DNA complexation mechanisms at the molecular level. It is well-known that the adsorption of DNA onto like charged lipid surfaces requires the presence of multivalent cations that act as bridges between DNA and anionic lipids. Unfortunately, the molecular mechanisms behind such adsorption phenomenon still remain unclear. Accordingly a historical background of experimental evidence related to adsorption and complexation of DNA onto anionic lipid surfaces mediated by different multivalent cations is firstly reviewed. Next, recent experiments aimed to characterise the interfacial adsorption of DNA onto a model anionic phospholipid monolayer mediated by Ca^2 + (including AFM images) are discussed. Afterwards, modelling studies of DNA adsorption onto charged surfaces are summarised before presenting preliminary results obtained from both CG and all-atomic MD computer simulations. Our results allow us to establish the optimal conditions for cation-mediated adsorption of DNA onto negatively charged surfaces. Moreover, atomistic simulations provide an excellent framework to understand the interaction between DNA and anionic lipids in the presence of divalent cations. Accordingly,our simulation results in conjunction go beyond the macroscopic picture in which DNA is stuck to anionic membranes by using multivalent cations that form glue layers between them. Structural aspects of the DNA adsorption and molecular binding between the different charged groups from DNA and lipids in the presenceof divalent cations are reported in the last part of the study. Although this research work is far from biomedical applications, we truly believe that scientific advances in this line will assist, at least in part, in the rationaldesign and development of optimal carrier systems for genes and applicable to other drugs.     

10～35kV电力系统母线微机保护装置

介绍了一种电力微机保护系统,采用CAN总线通讯,缩短了母线的故障切除时间,提高了电力系统的稳定性,实现母线分布式保护功能。处理器DSPIC33MC506带有DSP核,能够快速地实现数字处理算法,提高了系统的实时性。支线保护结合三点电流瞬时值检测,使故障判断更可靠。     

基于单目视觉的智能寻迹小车设计与实现

目的研究基于单目视觉的智能小车循迹运动控制技术。方法通过HQ7620数字摄像头采集路径信息,采用快速OTSU自适应阈值算法获取路径引导中心线,计算并获得小车移动方向和速度控制参数,用PID算法对小车的舵机和直流电机进行闭环控制。结果设计并实现了一种以MC9S12XS128单片机为核心控制模块的智能循迹小车系统。实验结果表明,该智能循迹小车能够沿预设的引导线快速而稳定地行驶。结论设计方案简单可靠,具有较好的动态性能和鲁棒性,可应用于小型智能自主移动机器人的视觉导航控制。     

用蒙特卡罗“测量”离散程序中的参数

为了快速、精确地计算高能X射线照相中的散射光子分布,提出了将该过程中的粒子输运问题近似为一个有效的纯光子输运问题。针对该纯光子输运方程提出了一种适合于计算机计算的逐级迭代求解公式,并将该公式进行了离散化,然后编写成了计算机离散程序。用蒙特卡罗程序MCNP模拟得到了该程序所需要的参数和分布函数。最后用MCNP对该程序进行了检验。对于薄客体离散程序的计算结果与MCNP符合较好,但对于厚客体二者有较大偏离。目前可以把该程序应用于一些定性的计算分析。     

A k-mean-directions Algorithm for Fast Clustering of Data on the Sphere

A k-means-type algorithm is proposed for efficiently clustering data constrained to lie on the surface of a p-dimensional unit sphere, or data that are mean-zero-unit-variance standardized observations such as those that occur when using Euclidean distance to cluster time series gene expression data using a correlation metric. We also provide methodology to initialize the algorithm and to estimate the number of clusters in the dataset. Results from a detailed series of experiments show excellent performance, even with very large datasets. The methodology is applied to the analysis of the mitotic cell division cycle of budding yeast dataset of Cho et al. [Molecular Cell (1998), 2, 65–73]. The entire dataset has not been analyzed previously, so our analysis provides an understanding for the complete set of genes acting in concert and differentially. We also use our methodology on the submitted abstracts of oral presentations made at the 2008 Joint Statistical Meetings (JSM) to identify similar topics. Our identified groups are both interpretable and distinct and the methodology provides a possible automated tool for efficient parallel scheduling of presentations at professional meetings.

The supplemental materials described in the article are available in the online supplements.