Implementing Dynamic Boundary Conditions with the Material Point Method

The material point method (MPM) is gaining an increasing amount of attention due to its capacity to solve geotechnical problems involving large deformations. Large deformations in geotechnics usually involve the failure process and therefore dynamic analyses are often carried out. However, simulating the (infinite) continuous domain using...

Generalizing Simultaneously to Support Smooth Zooming: Case Study of Merging Area Objects

When users zoom in or out on a digital map, the map should change correspondingly to present geographical information at proper levels. A way to help map users better keep track of their interested objects is to change the map smoothly instead of discretely switching between several levels of detail. This paper focuses on the problem of...

Finding Optimal Sequences for Area Aggregation-A* vs. Integer Linear Programming

To provide users with maps of different scales and to allow them to zoom in and out without losing context, automatic methods for map generalization are needed. We approach this problem for land-cover maps. Given two land-cover maps at two different scales, we want to find a sequence of small incremental changes that gradually transforms one...

Paralleling generalization operations to support smooth zooming: case study of merging area objects

When users zoom out on a digital map, some area objects become too tiny to be seen, resulting in visual clutters. To avoid this problem, the relatively unimportant areas should be merged with their neighbors to form larger<br/>areas. In order to provide small and smooth changes so that users can easily keep their contexts, we merge a pair of...

Multi-layer vario-scale web map comparer with dynamic transitions and visual analytical tool

This paper presents a web map juxtaposition comparer. Using the comparer, we can place two maps side by side for comparison. The maps of the comparer can contain multiple layers, and each of them can be a multi-scale layer<br/>or a vario-scale layer. We enhance the comparer’s visual analytical ability by developing more functionalities,...

Design and development of a system for vario-scale maps

Continuous Road Network Generalization throughout All Scales

Until now, road network generalization has mainly been applied to the task of generalizing from one fixed source scale to another fixed target scale. These actions result in large differences in content and representation, e.g., a sudden change of the representation of road segments from areas to lines, which may confuse users. Therefore, we aim...

All roads lead to ROMA: Design and evaluation of a Robust Online Map-generation Algorithm based on position traces

Keeping maps up to date is quite costly because road geometry changes over time and mapping by professional surveyors is an expensive operation. With the presence of GPS sensors on mobile phones and in most cars today it becomes possible to measure the location of roads with many measurements from sensors of lower accuracy. In this thesis we...

Pattern classification approaches to matching building polygons at multiple scales

Matching of building polygons with different levels of detail is crucial in the maintenance and quality assessment of multi-representation databases. Two general problems need to be addressed in the matching process: (1) Which criteria are suitable? (2) How to effectively combine different criteria to make decisions? This paper mainly focuses on...

Displacement methods based on field analysis

Characterization and detection of building patterns in cartographic data: Two algorithms

Building patterns are important features in applications like automated generalization and spatial data mining. Many previous work has however focused on a few specific patterns (i.e. collinear pattern), while many others are less discussed. This paper proposes a comprehensive typology of available building patterns through the study of existing...