1) Continuous Direction Query
连续方向查询
1.
The Object-Orientation-based Continuous Direction Query Optimization;
基于对象方位的连续方向查询的优化技术
2) continuous queries
连续查询
1.
The traditional heuristic algorithm of pushing selection predicates below joins is possibly less efficient for continuous queries,because early selection destroys the ability to share subsequent high cost join processing.
深入研究了适合数据流连续查询处理的Shared PushDown,PullUp和Filtered PullUp三种可共享连接结果的策略。
2.
A novel data streams partitioning method is proposed to resolve problems of range-aggregation continuous queries over parallel streams for power industry.
为了解决电力工业中并行数据流范围聚集的连续查询问题,提出一种新颖的数据流划分方法。
3.
Sensor network in a lot of applications have proposed many new challenge to traditional real-time such as the heterogeneity of the underlying data source or I/O devices,real-time of processing continuous queries and adaptively quality of service etc.
传感器网络在解决底层数据源和I/O设备的异构性、处理连续查询的实时性、服务质量自适应等方面提出了许多新的挑战。
3) continuous query
连续查询
1.
Load shedding for continuous query on different important input streams;
一类数据流连续查询的降载策略研究
2.
Design and Implementation of Continuous Query Processing Prototype System over Data Streams;
数据流连续查询处理系统设计与实现
3.
Multiple continuous query optimization over data stream
数据流多连续查询优化技术
4) continuous skyline query
skyline连续查询
5) direction query
方向查询
1.
Spatial direction query based on projection model
基于投影模型的空间方向查询
2.
This paper analyzes the principle of spatial direction query based on cone model, and proposes the idea of selecting proper spatial directional relation formal description model according to different applications and different features of spatial data.
分析了基于锥形模型进行空间方向查询的原理,提出应结合不同实际应用领域和针对不同的空间数据特征选择适当的空间方向关系形式化描述模型的思想。
6) CKNN queries
连续k近邻查询
1.
In order to process CKNN queries on the basis of TPR-tree efficiently,a new spatio-temporal distance metrics minmaxdist(t) was presented as a pruning upper bound.
针对基于TPR树索引的连续k近邻查询,引入了一种新的时空距离度量最小最大距离函数作为TPR树索引搜索时节点剪枝上界。
2.
By introducing directional network distance measurement we proposed the directional network expansion(DNE) algorithm to reduce the network searching cost of CKNN queries processing.
基于道路网络的连续k近邻查询是移动对象数据库领域的研究重点和热点。
补充资料:连续和非连续孔径射电望远镜
射电望远镜因接收天体射电的天线孔径的构成方式不同,而有连续孔径和非连续孔径之分。连续孔径射电望远镜是射电望远镜的一种最简单的类型,其天线孔径为接收单元所布满,因而天线增益和分辨率全由天线孔径的实际尺寸和形状决定。这类望远镜天线孔径可以有各种形状,如通常的抛物面、球面、抛物柱面、抛物带形反射面等。某些由分立天线(如偶极子天线、裂缝波导等)组成的天线阵,当阵元间距不大于半波长时,由于电场强度方向图和连续面电流分布的场强方向图相似,也被认为是连续孔径射电望远镜。这种情况更常见于线孔径或米波、十米波段的偶极子阵。非连续孔径射电望远镜是天线结构只分布在孔径部分面积内的望远镜,通常由多个天线组成。栅式干涉仪、复合射电干涉仪、栅十字、 T形栅、圆阵、圆环以及综合孔径射电望远镜等都是。这种望远镜的分辨率由天线范围(设想的孔径)的外尺寸决定,而总的天线增益或灵敏度,则取决于全部天线单元面积的总和。图中a所示的连续孔径天线可认为由N个单元面积组成,经天线传至接收机的信号是各单元反射信号的迭加,连续孔径射电望远镜通过焦点处的馈源自动得到这种迭加。由于二单元A、B信号的迭加效果等效于处在A、B的相关干涉仪输出,非连续孔径射电望远镜正是基于这个原理,在省去孔径一部分的情况下,保留连续孔径各单元间的全部间距和取向,如图中b所示的"骨架式"射电望远镜,或者依观测需要对这些间距和取向进行有限的采样(各种干涉阵),甚至用不少于2的有限天线依次采样后进行处理;图中c是综合孔径望远镜。
说明:补充资料仅用于学习参考,请勿用于其它任何用途。
参考词条