Cross-Border Migration of Hong Kong Residents Under the 'One Country, Two Systems' Policy

Hong Kong is known as a migrant city because its population was sourced from mainland China, and because there has always been outflows of people to overseas countries, especially from the mid-1980s to mid-1990s. Emigration to mainland China has become a significant recent trend. This article discusses this phenomenon in the theoretical contexts of migration and trans-border residential development. It contends that the trend will intensify more quickly than other cross-border movements because the two systems are separated by a political border within one country, and because there are common cultural ties and rapid economic integration.     

基于CK810处理器的汇编链接时优化

提出基于CK810处理器的16/32位混编指令集汇编链接时优化技术。利用汇编输出二进制文件,根据CK810处理器的16/32位混编指令集中指令及操作数的特征,动态选择指令的编码方式,实现对指令relax,最大程度地提高了程序的代码密度。对于在汇编时不能确定编码方式的指令,通过留出重定位的方式,由链接时完成优化。在链接时,利用信息的确定性,实现对整个程序的压缩和指令的替换,使得程序执行效率更高,代码占用空间更小。汇编链接时优化技术克服了传统编译器只限于一个模块优化的缺点,把优化范围扩展到整个程序,实现了跨模块的优化,使得基于CK810处理器的程序代码密度平均提高7.52%,性能平均提升7.91%。     

基于STL文件的Laplacian网格优化算法

针对直接重构得到且以STL文件格式存储的网格模型质量不高的问题, 提出了一种基于Laplacian坐标的网格模型全局优化算法。该算法在提高三角面片质量的同时可以很好地保持原网格模型的局部几何特征, 其核心思想是通过在最小二乘意义下求解由权重控制的包含顶点位置和拉普拉斯坐标双重约束的线性系统来对网格顶点进行重新定位。从实验结果可以看出, 该算法较以往的Lapacian优化算法在对网格细节特征的保持上有一定优势。     

一种混合无线传感器网络内覆盖洞修补的分布式启发算法

首先对最小化最大移动开销移动传感器分布式算法设计进行了分析, 并指出在分布式条件下难以对此类算法中的输出分派移动传感器的最大开销进行限制, 随后提出了一种分布式启发算法。该算法将移动传感器和覆盖洞视为节点, 在节点和节点的邻居间通过有限数量消息实现匹配。仿真结果显示, 算法可实现最高达到85%的覆盖洞修补率以及较低的移动传感器最大移动开销, 使其更能适用于实际无线传感器网络环境。     

库区旅游开发带动型水库移民安置模式探讨

库区旅游开发与水库移民安置工作互相促进,密不可分。提出了库区旅游开发带动型水库移民安置模式．分析了当前库区旅游开发推动水库移民安置工作中存在的问题,包括以旅游发展推进移民安置工作的观念落后、库区旅游开发不足、政策与管理水平不高、库区移民参与旅游开发的能力有待提高等,并有针对性地进行了发展对策探讨。     

一种基于PIM-SM的扩展组播路由EPIM-SM的设计

提出了一种基于PIM-SM的新的扩展协议EPIM-SM(extend to PIM-SM).该协议采用了一种新的算法代替PIM-SM用于RP选举的哈希算法,新协议提供这样一种机制:根据网络拓扑结构及组播源和成员的变化情况,为每个候选RPi估算其组播树整体代价,定期选择一个代价值最小的RP,以使组播树的代价始终保持接近最低.     

分析广东省气象局中心机房搬迁之注意事项

通信机房搬迁是气象信息网络运行维护工作中一项重难点工程,特别是在保证各个气象业务、信息系统运行的连续性下进行整体搬迁。该文对平日气象信息网络管理工作的各个要点进行研究,并阐述该要点在通信机房搬迁中的应用,提出机房搬迁中的注意事项。体现气象信息网络日常管理工作的重要性。     

A modified advancing layers mesh generation for thin three-dimensional objects with variable thickness

A method of generating modified advancing layers mesh is proposed. In this paper the mesh generation process of semi-unstructured prismatic/tetrahedral mesh is presented for relatively thin three-dimensional geometries with variable thickness, as in the case of injection molding analysis. Prismatic meshes are generated by offsetting initial surface triangular meshes. During the mesh generation process, mesh quality is efficiently improved with the use of a new node relocation method. Finally, tetrahedral meshes are automatically generated in the rest of the domain. The mesh generating capability of the proposed algorithm is demonstrated with the several practical test cases.     

堆场集装箱翻箱的PCNN优化控制算法

集装箱的堆存状态与理想发箱顺序很难保持一致, 翻箱操作是不可避免的. 为降低堆场的翻箱率, 提高作业效率, 在获得集装箱的取箱顺序前提下, 将每取一个集装箱所产生的可能状态视为一个状态结点, 所需的翻箱次数加一个基数作为状态结点间的连接权, 把翻箱优化问题转化为最短路径求解问题. 脉冲耦合神经网络(Pulse-coupled neural network, PCNN)具有独特的自动波并行传播的特性, 适用于求解大规模实时问题, 能一次求出源点到其他所有目标点的最短路径, 从而获得最优的翻箱方案. 其所需要的计算量仅正比于最短路径的长度, 与路径图的复杂程度及路径图中的通路总数无关. 这为建立集装箱的智能控制系统奠定了坚实的理论基础.     

Particle Effects on Penetration and Solidification of Flowing Mixed Melts on Metal Structures

In severe-accident analyses of liquid-metal-cooled reactors, assessing the relocation and solidification of disrupted core materials is of importance. We investigate here the fundamental characteristics of these behaviors in flowing melt mixed with solid particles under various conditions. To simulate the melts, we use a low-melting-point metal (viz., Bi-Sn-In alloy) mixed with various concentrations of copper and bronze as solid particles; the flow channels used were inclined open ones with a V-shaped cross section made of either stainless steel or brass plate. Transient melt flow was recorded, and melt penetration lengths and frozen melt distributions along the channel were measured. Results indicate that penetration length decreases for molten-metal/solid particle mixtures (mixed melts) compared with a pure molten metal (a pure melt), as well as decreases with decreasing solid particle size and increasing particle volume fraction in the melt. For the pure melt, we found only one freezing mode of all melt adhesions along the channel, whereas there were two freezing modes of melt separation with high solid particle concentrations, as well as melt adhesion, along the channel for mixed melts. The results obtained will be utilized in an experimental database to validate and improve physical models used for reactor safety analysis codes.