In an era of mobile internet and big data, how to make the data access more efficient is worth researching because the mobile computing environments have some limitations such as the narrow bandwidth, the frequent disconnections of network and so on. To improve the response time of query, a good cache system is of vital importance. Besides, a good cache consistency method is essential to ensure the correctness. In this paper, a semantic cache supporting version-based consistency is proposed. This cache mainly have two advantages. On one hand, it can obviously improve the response time of query and the hit ratio of the cache. On the other hand, the version-based consistency enhances the stability of the system especially in high-concurrency situations. Several experiments has been carried out and the results are presented to show the performance of the cache.

Video summarization is receiving increasing attention due to the large amount of video content made available on the Internet. In this paper we present a novel idea to track video from multiple sources for video summarization. An algorithm that takes advantage of both video and close caption text information for video scene clustering is described. Experimental results are given followed by discussion on future directions.

This paper presents a framework for a customizable MPEG-4 face player using a FAPs (Facial Animation Parameters) sequence recovered from a real-time image sequence. First, the 3D nonrigid motion and structure of the facial features is recovered from a 2D image sequence and a "person-specific" model of the face. The model consists of the intensity and range image of the face. Then, the FAPs are computed from the recovered 3D structure. The customizable MPEG4 face animation is generated using a FAP sequence and a model of a specific person. The dataset of four face image sequences from three different face orientations equipped with range images are used. The GT (ground truth) results are generated using the 3D structure provided by range images. The results are evaluated quantitatively by comparing recovered FAP values, and qualitatively by comparing the generated MPEG-4 animations. FAPs are recovered up to 8% (relative) and 16 FAP units (absolute) accuracy and the animation is nearly identical to the MPEG-4 animation using GT FAPs.

We describe a new approach to animating generic 3D wireframe models of human heads using MPEG-4 synthetic/natural hybrid coding (MPEG4/SNHC) facial definition parameters (FDP) points and facial animation parameters (FAP) streams. The FDP points are used to partition a head model into sections that have approximately conforming motion with human muscles. Using the borders of these sections as features, a 3D morphing algorithm is developed to morph vertices from one frame to the next while preserving the qualities of facial expressions such as those of human visual speech. A comparison is made with the facial animation table (FAT) approach proposed in MPEG-4/SNHC. Experimental results on standard FAP sequences and on a proprietary system are shown.

This paper presents a computational framework to extract salient patterns, called vortex structures, from 3D turbulent fluid flows. These structures can be characterized as regions of dominating rotational motion in the velocity fields and intensity concentrations in the corresponding vorticity fields. A pointwise linear representation is employed to approximate the kinematics of the flow field, and the fluid motion is classified according to motion analysis or topological patterns. The regions of vortex structures are identified as those dominated by rotational motion or those of focus-type singularity. The 2D vortices, as a special case of 3D vortices, are detected by searching for regions of vorticity concentrations.

Unlike other image templates, visemes have identities in two different media. In audio domain, they are often related to basic linguistic units such as phonemes. In image domain, they are defined by the images of human articulators, such as mouth shapes, chin movements, etc. In this paper, an approach of extracting visemes from both image and acoustic domains is presented. In image domain, the mouth shapes, represented by feature points on inner lip contours, are extracted through face tracking and mouth image analysis. In acoustic domain, viseme segments are obtained automatically by aligning phoneme strings to audio signals through a Viterbi alignment process.

This paper presents a framework for analyzing salient patterns (vortex structures) in the velocity fields of turbulent fluid flows. Vortices are modeled as rotational motions in the velocity fields and concentrations in the corresponding vorticity fields. A pointwise linear model is then built to approximate the kinematics of the flow field. Locally, the vector fields are analyzed in terms of fluid motion and singular patterns. The regions of vortex structures are then extracted by identifying those dominated by rotational motion or those of focus-type singularity. In addition to this, 2D vortices, as a special case, are detected by searching regions of vorticity concentrations. The algorithm is applied to both 2D and 3D, experimental and computational turbulent flows.>

The authors investigate the problem of interpolating, under physical constraints, 3-D vector fields from sample vectors at random positions. This problem arises from analysis of fluid motion, but the results can also be applied to such areas as geometric modeling, approximation theory, and other types of nonrigid motion. The algorithm proposed combines the generalized multivariable quadratic interpolation and physical constraints into one step to form an overdetermined linear equation system whose solution gives the coefficients of interpolation, which are much less sensitive to noise compared to other interpolation methods. The authors utilized methods in robust statistics to detect outliers in the sample data so that the results are more stable in the presence of gross errors. The algorithm is applied to both synthesized velocity fields of fluid and empirically measured 3-D velocity fields.>