Addresses are important data for urban applications. About 80% of the information local authorities use have a geographic component that is generally related to addresses. Addressing systems efficiency depend on the q...Addresses are important data for urban applications. About 80% of the information local authorities use have a geographic component that is generally related to addresses. Addressing systems efficiency depend on the quality of addresses locators. There are several methods to collect data. Surveys from the field are essential: GPS and pre-printed maps can be used to achieve this goal. GPS surveys from the field may be a solution, but it remains practical only for limited areas. To insure an accepted accuracy, GPS methods need special considerations that are time and money consuming. For Casablanca’s addressing locators, an alternative approach was adopted to collect 400 000 points. It took two months, 200 operators and 3500 printed maps to cover a study area of1,226 km2. This paper is to develop an optimized approach based on automated procedure for reintegrating printed maps in a geographic information system (GIS). It saves georeferencing time from 5min to just seconds per document. It insures, more importantly, an accuracy that is between20 cmto1 mfor scales that are between 1/500 and 1/2500. It ensures maps’ integration, independently of base map and coordinates system by introducing the notion of Georeferencing Code (GC).展开更多
The quality control of geographic data, especially from a topological and semantic perspective, is a must for its good management and use. However, while updating spatial data, some sorts of anomalies are affecting it...The quality control of geographic data, especially from a topological and semantic perspective, is a must for its good management and use. However, while updating spatial data, some sorts of anomalies are affecting it, due to negligence or non-respect of business and topological rules. Hence the necessity of a solution that enables detecting theses anomalies. Nowadays, Geographic Information Systems (GIS) have become essential for decision-making in any project that manages spatial data. GIS functionalities and tools give the possibility of defining the topology of vector data. Nevertheless, the topology alone does not respond to the needs in matter of defining specific rules for every facility network. This means, we could find topological errors in the spatial database, but taking into account business rules, they are correct and vice versa. The main objective of this article is firstly to define business rules for the linear elements of a network. Secondly to premeditate the algorithms that detect the violation of the defined rules in order to have a good quality control of geographic data.展开更多
文摘Addresses are important data for urban applications. About 80% of the information local authorities use have a geographic component that is generally related to addresses. Addressing systems efficiency depend on the quality of addresses locators. There are several methods to collect data. Surveys from the field are essential: GPS and pre-printed maps can be used to achieve this goal. GPS surveys from the field may be a solution, but it remains practical only for limited areas. To insure an accepted accuracy, GPS methods need special considerations that are time and money consuming. For Casablanca’s addressing locators, an alternative approach was adopted to collect 400 000 points. It took two months, 200 operators and 3500 printed maps to cover a study area of1,226 km2. This paper is to develop an optimized approach based on automated procedure for reintegrating printed maps in a geographic information system (GIS). It saves georeferencing time from 5min to just seconds per document. It insures, more importantly, an accuracy that is between20 cmto1 mfor scales that are between 1/500 and 1/2500. It ensures maps’ integration, independently of base map and coordinates system by introducing the notion of Georeferencing Code (GC).
文摘The quality control of geographic data, especially from a topological and semantic perspective, is a must for its good management and use. However, while updating spatial data, some sorts of anomalies are affecting it, due to negligence or non-respect of business and topological rules. Hence the necessity of a solution that enables detecting theses anomalies. Nowadays, Geographic Information Systems (GIS) have become essential for decision-making in any project that manages spatial data. GIS functionalities and tools give the possibility of defining the topology of vector data. Nevertheless, the topology alone does not respond to the needs in matter of defining specific rules for every facility network. This means, we could find topological errors in the spatial database, but taking into account business rules, they are correct and vice versa. The main objective of this article is firstly to define business rules for the linear elements of a network. Secondly to premeditate the algorithms that detect the violation of the defined rules in order to have a good quality control of geographic data.
