Contextual Line Simplification (CLS) for ArcGIS

地球表面的地图或可视化表示较小比例尺的地理特征。因此， 它包含的信息必须限制为可以以地图比例以图形方式呈现并适合地图的信息 5~6成熟。这一调整过程称为泛化。中的一个基本泛化过程 制图是一种简化，适用于线状要素。线条的简化涉及去掉高位 密度顶点，基于给定的标准(例如，通过控制 从原始的广义线；道格拉斯-普克算法)，以降低复杂性或冗余 数据集。近年来，随着移动定位技术的快速发展，一系列新的应用 (例如，机队管理系统、基于位置的服务)已经出现，它们产生了大量的 时空(流动性)数据。原始移动性数据通常包括时空位置(三元组：x，y， T)具体对象或抽象概念(例如，传播疾病)，它们形成了描述 单个物体的运动。要处理海量的移动性数据集合，通常需要 缩小它的尺寸。轨迹概化(也称为轨迹简化或压缩)一直是 并提出了一系列的解决方案。有代表性的算法扩展了 具有同步欧氏距离(SED)概念的Douglas-Peucker算法。 对静态或动态线(轨迹)的简化可能会导致目标线与空间冲突 在源线和空间中的某些其他对象之间应用的关系(拓扑、方向或距离)。 例如，海船轨迹的泛化可能导致目标轨迹与 小岛。建议的方法通过引入上下文简化来解决这一问题 将其他层视为上下文约束的静态和动态线性要素。此方法将是 集成到ArcGIS-领先的地理信息系统软件包-工具集，以支持 线状要素的上下文简化，以造福于GIS用户社区。

A map or visualization of the earth's surface represents geographic features in a smaller scale. Hence, the information it contains must be restricted to what can graphically be presented at map scale and fit in the map medium. This adjustment process is called generalization. One fundamental generalization process in cartography is simplification, which applies to linear features. Simplification of a line involves removal of high density vertices, based on a given criterion (e.g., minimize line distortion by controlling the offset of the generalized line from the original; Douglas-Peucker algorithm) to reduce complexity or redundancy in a dataset. Lately, with the rapid developments in mobile positioning technologies, a series of new applications (e.g., fleet management systems, location based services) have emerged, which produce vast amounts of spatiotemporal (mobility) data. Raw mobility data typically include the spatio-temporal locations (triplets: x, y, t) of either concrete objects or abstract concepts (e.g., spreading diseases) that form trajectories to describe the movement of individual objects. To handle the massive collections of mobility data there is usually a need to reduce its size. The trajectory generalization (also referred as trajectory simplification or compression) has been considered in the past and a series of solutions have been proposed. A representative algorithm extends the Douglas-Peucker algorithm with the notion of Synchronous Euclidean Distance (SED). The simplification of a static or dynamic line (trajectory) may result in a target line that violates the spatial relations (topological, direction or distance) that apply between the source line and some other objects in space. For example, the generalization of a sea vessel trajectory may result into a target trajectory that intersects an island. The proposed methodology resolves this problem by introducing a contextual simplification of both static and dynamic linear features considering other layers as contextual constraints. This method will be integrated into ArcGIS - the leading Geographic Information System software package - toolset to support a contextual simplification of linear features for the benefit of the GIS user community.