Earticle

In the field of computer graphics, fluid-like motion is an important and challenging problem with many applications. Currently, the graphical performance and resolution of the mobile handset is highly improved; therefore, mobile 3D games and physically based animations are also more and more popular items in the mobile services. Yet interactive physically-based fluid simulation is still challenging for mobile games. We studied and implemented physically-based models based on Navier-Stokes equation for fire and smoke effects on mobile 3D games. To make an efficient fire effects on mobile games, we implemented billboard based 2D fluid simulation and gradient based coloring effects. We also implemented external forces on billboard for interactive fire simulation with game characters. The mobile platform of our system is WIPI, which is the standard mobile platform in Korea and NF3D for our 3D programming API. All the simulations have also been adopted for our mobile 3D game, “Rupee Story”.

Software services distributed in open wireless environments are implemented using different middleware types and advertised using different discovery protocols. Client application needs to adopt a flexible approach to discover and bind these services. Compared with other related work, this paper presents a new reflective coordination middleware based on mobile agent. It dynamically adapts both its binding and discovery protocol to allow interoperation with heterogeneous services by uploading different functional components. By dynamically creating subagents at run time, it can interoperate with multiple services in parallel. As a result, the client burden is released, and the efficiency of the coordination process is enhanced.

In this paper, we propose a robust watermark technology to protect copyright. We enhance robustness of the watermark such that it can be used to protect the intellectual property even after serious attacks on the watermarked image. In the proposed watermarking, we embed watermarks by Singular Value Decomposition and Distributed Discrete Wavelet Transformation techniques. Regarding our method, Singular Value Decomposition provides the robustness to protect the image from most attacks except cropping, while Distributed Discrete Wavelet Transformation disperses watermarks all over the image to resist cropping attacks. The robustness of our proposed watermark scheme has been verified experimentally against main kinds of watermark attacks such as geometric and signal processing attacks.

Lifelog is a set of continuously captured data records of our daily activities. The lifelog data usually consists of text, picture, video, audio, gyro, acceleration, position, annotations, etc., and is kept in some large databases as records of individual’s life experiences, which can be retrieved when necessary and used as reference to improve life’s quality. The lifelog in this study includes several types of media data/information acquired from wearable multi sensors which capture video images, individual’s body motions, biological information, location information, and so on. We propose an integrated technique to process the lifelog which is composed of both captured video (called lifelog images) and other sensed data. Our proposed technique, called Activity Situation Model, is based on two models; i.e., the space-oriented model and the action-oriented model. By using the two modeling techniques, we can analyze the lifelog images to find representative images in video scenes using both the pictorial visual features and the individual’s context information, and to represent the individual’s life experiences in some semantic and structured ways for future experience data retrievals and exploitations. The resulting structured lifelog images were evaluated using the previous approach and the proposed technique. Our proposed integrated technique exhibited better results.

In this paper, a generalized multimedia database data model based on MPEG-7 named G3M is proposed and formally defined. Different from those XML Database Management System (DBMS) solutions for MPEG-7 storage and retrieval, G3M analyses the MPEG-7 Multimedia Description Schemes (MDS) throughout to construct user-preferred database schemas, and the prototype system is built on extensible Object-Relational DBMSs. With the strong expressiveness of MPEG-7, G3M represents various aspects of multimedia data well. Domain knowledge for special application demand can be defined and used as references in G3M.

A wireless multihop ad hoc network is emerging as an important area for new developments in the ubiquitous network. Although ad hoc network is attractive solution, there are still some challenges in robustness and security issues. In this paper, we have depicted a secure framework for multipath routing in wireless multihop network, which is complete solution for end-to-end security for multpath wireless multihop network. We have analyzed the performance the proposed framework.

Denial of service attacks occur when the attacks are from a single host, whereas distributed denial of service attacks occur when multiple affected systems flood the bandwidth or resources of a targeted system. Although it is not possible to exempt entirely from denial of service or distributed denial of service attacks, we can limit the malicious user by controlling the traffic flow. In the paper, we propose to monitor the traffic pattern in order to alleviate distributed denial of service attacks. A bandwidth allocation policy will be adopted to assign normal users to a high priority queue and suspected attackers to a low priority queue. Simulations conducted in network simulator of our proposed priority queue-based scheme shows its effectiveness in blocking attacking traffic while maintaining constant flows for legitimate traffic.

With a large quantity of data and services existing in virtual organization, query routing is an efficient approach to satisfy entities on community for their requirements of knowledge. The entities, which are organized according to the semantic relationship of each other, together with the query routing method under the guidance of semantics, endeavor to meet the querist with the most relevant answer. This paper proposes an extended query routing method that draws on the relationships between different concepts on Domain Ontology to mine the relationship between the knowledge querist holds and the knowledge querist wants. Through Related Segmentation of Ontology Algorithm, this paper tries to explore a cognitive chain to get the querist to fully understand how the knowledge in answer comes about, and to infer the answer querist wants to know.