Catálogo de publicaciones - libros

In order to meet the need for 3D real-time dynamic visualization of mass terrain data, the spatial database in Grid GIS is taken as the data source of large-scale terrain scenes. Mass terrain data from distributed heterogeneous GIS spatial database are integrated, and their storage and access methods are designed on the basis of grid concept, ensuring that 3D terrain scene from any spatial information source can serve users on demand anywhere at any time. In addition, according to the requirements for low delay and high throughput of terrain data transmission, both the filtering mechanism of terrain data and multi-path data transport service are proposed so as to achieve the best possible viewing experience under the current network conditions. The experimental results show that the proposed mechanism is effective.

In this paper, we describe a system of multi-touch tabletop display and its control algorithm for Google-earth that utilizes hand gesture as mouse free interaction. The system adopts well known FTIR technique. The hand gesture of necessary instruction is predefined according to the number, position, and movement of the fingertips which are obtained from multi-touch of a single user. The system consists of a beam-projector and an acrylic screen attaching infrared LED as light source, and an infrared camera for capturing the fingertip image. Input image is preprocessed with simple morphological method to remove the noise and to determine the fingertip region. In recognition process, gesture commands are recognized by comparing the preprocessed image with predefined gesture model of fingertips. In detail, firstly the number of the spot; fingertip mark, angles among the spots, and Euclidean distance between two spots are calculated, and then the values are compared with the information of the model. The effectiveness of the system can be proved through the experimental results.

This paper deals with the problem of finding the largest navigable areas around a mobile robot, which is important for navigation and action planning. We propose a method to obtain reliable dense 3D maps using a novel omnidirectional stereo vision system. The vision system is composed of a perspective camera and two hyperbolic mirrors. Once the system has been calibrated and two image points respectively projected by upper and below mirrors are matched, the 3D coordinate of the space point can be acquired by means of triangulation. To achieve the largest reliable dense matching, our method are divided into three steps. First reliable FX-dominant matching; then feature matching and ambiguous removal; finally the remaining points between features are matched using dynamic time warping(DTW) with modified energy functions adapted well to our system. Experiments show that this proposed vision system is feasible as a practical stereo sensor for accurate 3D map generation.

As 3D graphics environment becomes the standards for most computer systems, it is natural to seek a 3D input device for manipulating an object in a 3D virtual world. Unlike 2D interface, however, 3D interface creates perceptual mismatches including depth perception problem. The objective of our research is to enhance the depth perception and 3D interaction by providing additional information based on the pictorial depth cues and interaction cues. In this paper, we investigated how to incorporate such cues. We designed two kinds of additional viewport that are to be placed on the top of the interaction window. One is a basic additional view with a different FOV, and the other is a compound view made up with 9 small sub-views with varying viewing direction. We also implemented two behaviors of the augmented view with respect to user interaction: Interactive Resizing and Holding-Z. Through a set of user performance tests, we have concluded that the basic additional view with Interactive Resizing and the additional compound view made statistically significant improvement on the performance of 3D interaction with a 3D input device.

Virtual Reality is an artificial environment created with computer hardware and software. Because it can create an environment that it is similar with the real world, thus it can solve the request of the study media. Now there are four types of VR systems: immersion VR, desktop VR, Unencumbered VR and Telepresence. This article introduced the four types and discussed the application of every type in the field education. And also point out what education benefits from using Virtual reality. What’s more, three main applications of VR in the field of network education were discussed. They are VR environment, VR laboratory and VR schooling.The emergence of VR would bring a profound influence VR to the education, and has a huge application prospect in the education domain.

This paper describes an embedded pedestrian navigation system composed of a self-contained sensors, the Global Positioning System (GPS) and an active Radio Frequency Identification (RFID) tag system. We use self-contained sensors (accelerometers, gyrosensors and magnetometers) to estimate relative displacement by analyzing human walking locomotion. The GPS is used outdoors to adjust errors in position and direction accumulated by the dead-reckoning. In indoor environments, we use an active RFID tag system sparsely placed in key spot areas. The tag system obviously has limited availability and thus dead-reckoning is used to cover the environment. We propose a method of complementary compensation algorithm for the GPS/RFID localization and the self-contained navigation represented by simple equations in a Kalman filter framework. Experimental results using the proposed method reveals that integration of GPS/RFID/dead-reckoning improve positioning accuracy in both indoor and outdoor environments. The pedestrian positioning is realized as a software module with the web-based APIs so that cross-platform development can easily be achieved. A pedestrian navigation system is implemented on an embedded wearable system and is proven to be useful even for unexperienced users.

Studies on olfactory communication using scents in addition to audio/visual information have recently become active. In a scent communication system, no representation scheme of scent information has been established due to lack of a basis for the smell. We introduced background scents that provide the ambience of image contents, and proposed a communication model for the background scents using sense-descriptive adjectives for association. The results of our experiments showed that the communication model is effective for enhancing the image contents.

This paper presents a hand shape recognition system using an active contour model (ACM) and applies it to an HCI to control a mobile robot. For the recognition of hand shapes, the technique should be developed to accurately track variously changing hands in real-time. For this, we develop a mean-shift embedded active contour (MEAC) which can improve the convergence speed and the tracking accurracy than the standard ACM. The proposed recognition system consists of four modules: a hand detector, a hand tracker, a hand shape recognizer and a robot controller. The hand detector locates a skin color region with a specific shape as a hand in the first frame. Thereafter, the detected region is accurately tracked through the whole video sequence by the hand tracker using a MEAC, and its shape is recognized using Hue moments. To assess the validity of the proposed system, we tested the proposed system to a walking robot, . The experimental results show the effectiveness of the proposed system.