A new parametric equation of state and quark stars

It is still a matter of debate to understand the equation of state of cold matter with supra-nuclear density in compact stars because of unknown non-perturbative strong interaction between quarks. Nevertheless, it is speculated from an astrophysical view     

Uniform star‐polystyrene nanoparticles prepared by emulsion atom transfer radical polymerization

Pentaerythritol (PT) was converted into four‐arm initiator pentaerythritol tetrakis(2‐chloropropionyl) (PT‐Cl) via reaction with 2‐chloropropionyl chloride. Uniform (monodisperse) star‐polystyrene nanoparticles were prepared by emulsion atom transfer radical polymerization of styrene, using PT‐Cl/CuCl/bpy (bpy is 2,2′‐dipyridyl) as the initiating system. The structures of PT‐Cl and polymer were characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The morphology, size and size distribution of the star‐polystyrene nanoparticles were characterized by transmission electron microscopy, atomic force microscopy and photon correlation spectroscopy. It was found that the average diameters of star‐polystyrene nanoparticles were smaller than 100 nm (30–90 nm) and monodisperse; moreover, the particle size could be controlled by the monomer/initiator ratio and the surfactant concentration. The average hydrodynamic diameter (D_h) of the nanoparticles increased gradually on increasing the ratio of styrene to PT‐Cl and decreased on enhancing the surfactant concentration or increasing the catalyst concentration. Copyright © 2011 Society of Chemical Industry     

中子星磁场研究进展

射电脉冲星，包括单星和双星，其观测特征被评论．双星脉冲星和毫秒脉冲星的短周期和弱磁场相关性暗示这些脉冲星是存在双星吸积过程的反加速脉冲星．最近提出的中子星磁场起源与演化模型进行了分析．     

脉冲星的辐射机制

介绍了脉冲星的磁偶极辐射模型，以及这个模型在理论与观测的比较上所存在的一些困难．还介绍了一种修正的脉冲星辐射模型，这个模型通过假定板冠区的低频偶极辐射，可以解决磁场演化问题     

双Y移30°绕组的交流励磁机谐波特性分析

文献［１］对双Ｙ移３０°绕组交流励磁机的四种运行方式的特性进行了分析。在此基础上本文进一步用富里叶级数对双Ｙ移３０°绕组交流励磁机的电压和电流波形进行谐波分析。根据位移角和换相角及电机参数，可以计算双Ｙ移３０°绕组交流励磁机的电压和电流波形以及整流输出特性。并将理论计算和实验结果进行了对照。结果表明，双Ｙ移３０°绕组的交流励磁机比不移相时具有较好的性能。该成果已在生产中应用。     

星链ER模型:一种数据仓库概念设计模型

对于流程工业中的数据仓库建设，存在一贯性质量分析的需求，即前一个工序的工艺可能影响下一个工序的产品质量．针对这种需求，提出了一种数据仓库的概念设计模型，星链ER模型．其中引入了链式事实主题结构的概念，并把度量细分为传递型度量与非传递型度量，给出了星链ER模型的图形表示法以及由概念模型到逻辑模型的转换规则．该模型可以方便地转化成多种逻辑模型如星型模式、雪花模式以及星座模式．     

On the performance of adaptive TDMA protocols in WDM passive star networks with fixed transmitters and tunable receivers

An adaptive time division multiple access (TDMA) protocol for WDM passive star networks using fixed transmitters and tunable receivers is presented. The proposed optical adaptive TDMA (OATDMA) protocol is capable of operating efficiently under bursty and correlated traffic. According to the proposed protocol, the stations which are granted permission to transmit at each time slot, are selected by taking into account the network feedback information. In this way, the number of idle slots is minimized and the network performance is significantly improved. Furthermore, although the traffic parameters are unknown and time-variable, the portion of the bandwidth assigned to each station is dynamically adapted to the station’s needs.     

约束概念格及其构造方法

概念格是一种有效的数据分析和知识提取的形式化工具．然而，随着要处理的数据量的剧增，基于原始形式背景构造出的概念格结点数目庞大，占用大的存储空间，同时概念格结点中一些属性集形成的内涵，用户并不都感兴趣，因而从中提取用户需求知识费时．为了降低概念格构造的时空复杂性，增强实用性和针对性，首先采用谓词逻辑描述用户感兴趣的背景知识，并将背景知识引入到概念格结构中，提出了一种新的概念格：约束概念格．在此基础上，提出了基于背景知识的约束概念格构造算法CCLA．理论分析表明，该算法能有效地减少概念格的存储空间和建格时间．最后，采用恒星天体光谱数据作为形式背景，实验验证了该算法的有效性．     

联机分析查询处理中的一种聚集算法

联机分析处理(online analytical processing,简称OLAP)查询是涉及大量数据的即席复杂查询,从SQL(structured query language)角度来看,这些查询通常都包含多表连接和分组聚集操作.从OLAP查询处理角度出发,提出一种新的基于排序的聚集查询算法MuSA(sort-based aggregation with multi-table join).该方法充分考虑到数据仓库星型模式的特点,将聚集操作和新的多表连接算法MJoin相结合,排序时采用     

基于CCD星体跟踪器的舰船位置估计算法研究

CCD星体跟踪器作为舰船位置测量仪器，因其定位精度高、无位置积累误差、快速和智能化工作而受到重视。本文根据CCD星体跟踪器确定舰船位置的原理，介绍了一种用改进遗传算法来进行位置估算的新方法，仿真结果表明效果良好。