Spatio-Temporal Data Model

(1)提出了一种表示图像序列中出现的大量时空概念的方法。通过使用具有时间间隔的最小边界矩形（MBR）组成的长方体对目标进行近似建模。然后定义空间关系，包括拓扑关系和方向关系以及物体之间的距离。这些定义允许使用间隔对出现在图像序列中的对象进行时空查询的统一表示。我们还提供了用于内容检索的此类查询的示例，并说明如何在我们的方法中执行这些查询。(2)描述了一种实现时空概念数据模型的方法，该模型是我们在对象数据库系统上提出的类库。类库由三个类组成：时间类、空间类和时空类。作为类库的时态部分，我们基于所提出的时间间隔概念模型开发了时间间隔类。我们首先构建空间概念类，然后将其与时间间隔类相结合。我们还展示了一些使用类库的时空查询示例。此外，我们还研究了一种基于R*树的类库索引结构，从而可以有效地处理任何时空查询。

(1) We proposed a method for representing numerous spatio-temporal concepts appearing in image sequences. The objects are modeled approximately, by use of cuboids consisting of minimum bounding rectangles (MBR) with time intervals. The spatial relations, including topological and directional relations and the distances between objects, are then defined. The definitions allow for uniform representations of the spatio-temporal queries on objects appearing in image sequences using intervals. We also give examples of such queries for contents retrieval, and illustrate how they are performed in our method.(2) We describe a way of implementing a spatio-temporal conceptual data model which we have proposed as a class library on an object database system. The class library is composed of three classes : temporal, spatial, and spatio-temporal classes. As the temporal part of our class library, we exploit time-interval class based on time-interval conceptual model which we has proposed. We first build a class for spatial concepts, and then integrate the class with the time-interval class.We also showed some examples of spatio-temporal queries using class library. Moreover, we investigate an indexing structure based on R*-tree for the class library so that any spatio-temporal query can be efficiently processed with it.