研究背景

The moving objects databases field has been flourishing and there exist many hundreds, more likely thousands, of publications. However, very few of these results have made it into systems (research prototypes or commercial) and are available for practical use today.（移动对象数据库领域一直在蓬勃发展，并且有成百上千的出版物。 然而，这些结果中很少有人能将其制成系统（研究原型或商业）并在今天可供实际使用。）

研究内容

In this paper we describe an infrastructure for research in moving objects databases. （在本文中，我们描述了用于研究移动对象数据库的基础设施。）

• it allows researchers to implement their new techniques within a system context and to publish their research implementations together with the papers in such a way that readers of the paper can directly run the software, repeat the experiments, and even extend the experiments using other parameters and data sets.（它允许研究人员在系统环境中实现他们的新技术，并将他们的研究实现与论文一起发布，这样论文的读者可以直接运行软件，重复实验，甚至使用其他参数和数据集扩展实验。）
• it consists of SECONDO, an extensible database system into which a lot of moving object technology has been built already.（它由 SECONDO 组成，这是一个可扩展的数据库系统，其中已经构建了许多移动对象技术。）
  • SECONDOs architecture consists of three major components: the kernel, the optimizer, and the GUI.（SECONDO 的体系结构由三个主要组件组成：内核、优化器和 GUI。）
  •  The kernel is extensible by algebra modules. In fact, the entire implementation of a particular data model is done within algebra modules. An algebra module generally offers a set of type constructors and a set of operators.（内核可通过代数模块进行扩展。 事实上，特定数据模型的整个实现是在代数模块中完成的。 代数模块通常提供一组类型构造函数和一组运算符。）
  • The kernel is written in C++ and uses BerkeleyDB as the underlying storage manager. The optimizer is written in Prolog. The GUI is written in Java.（内核是用 C++ 编写的，并使用 BerkeleyDB 作为底层存储管理器。 优化器是用 Prolog 编写的。 GUI 是用 Java 编写的。）
• It offers BerlinMOD, a benchmark to generate large sets of realistic moving object trajectories together with a comprehensive set of queries.（它提供了BerlinMOD，这是一个基准测试，可以生成大量真实的移动对象轨迹，以及一组全面的查询。）
• it offers SECONDO Plugins as a facility to publish new research implementations that anyone can merge with a standard SECONDO distribution to have them run in a complete system context.（它提供 SECONDO 插件作为发布新研究实现的工具，任何人都可以将其与标准 SECONDO 发行版合并，让它们在完整的系统环境中运行。）