7 research outputs found
TO LOCALISE OR TO BE LOCALISED WITH WIFI IN THE HUBEI MUSEUM?
ISPRS The first method detects the beacon frames send by smartphones, laptops and other WiFi enabled devices in range using Libelium Meshlium Xtreme monitors. Their MAC addresses and the signal strength is measured by the Meshlium Xtreme and stored on an external database. We call this method WiFi monitoring. The second method a Wifi enabled device, like a smartphone, measures the signal strength of multiple Wifi Access Points in range to localise itself based on a previously created radio map. This method is known as WiFi fingerprinting. Both methods have some advantages and disadvantages. Advantages of the common way of WiFi fingerprinting are that the implementation costs are relatively low, because it is usually possible to use (a part of) the existing WiFi AP infrastructure. WiFi fingerprinting can reach a relatively high accuracy in the order of magnitude of meters. Finally, the location granularity can be adjusted to what is necessary for the purpose of the indoor localisation. This makes it employable for a wide range of purposes. The question remains how suitable these methods are for a 3D indoor navigation system for the Hubei provincial museum. One important aspect is the localisation-granularity necessary for the application. In a museum it is not necessary to know the exact X,Y position of a user (such high accuracy is unnecessary), more important is to know in which room the user is located so the information on exhibitions can be presented and the starting point of the navigation can be determined. Both methods can track the user and tell the room he or she is located at. Although WiFi smartphone monitoring may have a low update frequency it is still suitable for a navigation system for a museum since visitors usually spend more than a couple of minutes within a room
DISTANCE-VALUE-ADDED PANORAMIC IMAGES AS THE BASE DATA MODEL FOR 3D-GIS
Panoramic images portray a surround view of the real world in one image. This kind of presentation however does, alike regular pictures, not give any real depth information. Depth related relationships are only to be detected (within one image) by psychological cues like relative size, linear perspective and shadow. The relative distance between two features can only be retrieved by 1) stereoscopic measurement within two pictures or 2) by the integration of terrestrial laser scanning systems. In the second approach the photo is enhanced with information about the distance between each pixel and the location of image recording. If we visualize this cloud of ‘distance pixels ’ from a point of view chosen at the recording place through a panoramic perspective it will give us the impression of the original panoramic picture, but now with the added value of depth-related queries. This kind of ‘distance-valueadded’ panoramic pictures can be used as a base data model for 3D-GIS visualizations. This paper concentrates on the database organization of RGB laser scan point clouds, the creation of virtual ‘distance-value-added ’ panoramic images from these clouds, and the visualization and spatial analysis based on this kind of perception rich images. 1
Toward Seamless Indoor-Outdoor Applications: Developing Stakeholder-Oriented Location-Based Services
Abstract Location-Based Services (LBS), an emerging new business based on smartphone and mobile networks, are becoming more and more popular. Most of these LBSs, however, only offer non-seamless indoor/outdoor applications and simple applications without giving stakeholders the chance to play an active role. Our specific aim is to solve these issues. This paper presents concepts to solve these issues by expanding the Open Location Services Interface Standard (OpenLS) to allow seamless indoor/outdoor positioning and to extend the content of the services to include information recommended by stakeholders