Timothy K. Shih

Tag-Splitting: Adaptive Collision Arbitration Protocols for RFID Tag Identification

Tag identification is an important tool in RFID systems with applications for monitoring and tracking. A RFID reader recognizes tags through communication over a shared wireless channel. When multiple tags transmit their IDs simultaneously, the tag-to-reader signals collide and this collision disturbs a readers identification process. Therefore, tag collision arbitration for passive tags is a significant issue for fast identification. This paper presents two adaptive tag anticollision protocols: an Adaptive Query Splitting protocol (AQS), which is an improvement on the query tree protocol, and an Adaptive Binary Splitting protocol (ABS), which is based on the binary tree protocol and is a de facto standard for RFID anticollision protocols. To reduce collisions and identify tags efficiently, adaptive tag anticollision protocols use information obtained from the last process of tag identification. Our performance evaluation shows that AQS and ABS outperform other tree-based tag anticollision protocols.

An Adaptive Memoryless Protocol for RFID Tag Collision Arbitration

A radio frequency identification (RFID) reader recognizes objects through wireless communications with RFID tags. Tag collision arbitration for passive tags is a significant issue for fast tag identification due to communication over a shared wireless channel. This paper presents an adaptive memoryless protocol, which is an improvement on the query tree protocol. Memoryless means that tags need not have additional memory except ID for identification. To reduce collisions and identify tags promptly, we use information obtained from the last process of tag identification at a reader. Our performance evaluation shows that the adaptive memoryless protocol causes fewer collisions and takes shorter delay for recognizing all tags while preserving lower communication overhead than other tree based tag anticollision protocols

Technology supports for distributed and collaborative learning over the internet

With the advent of Internet and World Wide Web (WWW) technologies, distance education (e-learning or Web-based learning) has enabled a new era of education. There are a number of issues that have significant impact on distance education, including those from educational, sociological, and psychological perspectives. Rather than attempting to cover exhaustively all the related perspectives, in this survey article, we focus on the technological issues. A number of technology issues are discussed, including distributed learning, collaborative learning, distributed content management, mobile and situated learning, and multimodal interaction and augmented devices for e-learning. Although we have tried to include the state-of-the-art technologies and systems here, it is anticipated that many new ones will emerge in the near future. As such, we point out several emerging issues and technologies that we believe are promising, for the purpose of highlighting important directions for future research.

Exemplar-Based Video Inpainting Without Ghost Shadow Artifacts by Maintaining Temporal Continuity

Image inpainting or image completion is the technique that automatically restores/completes removed areas in an image. When dealing with a similar problem in video, not only should a robust tracking algorithm be used, but the temporal continuity among video frames also needs to be taken into account, especially when the video has camera motions such as zooming and tilting. In this paper, we extend an exemplar-based image inpainting algorithm by incorporating an improved patch matching strategy for video inpainting. In our proposed algorithm, different motion segments with different temporal continuity call for different candidate patches, which are used to inpaint holes after a selected video object is tracked and removed. The proposed new video inpainting algorithm produces very few ldquoghost shadows,rdquo which were produced by most image inpainting algorithms directly applied on video. Our experiments use different types of videos, including cartoon, video from games, and video from digital camera with different camera motions. Our demonstration at http://member.mine.tku.edu.tw/www/T_CSVT/web/shows the promising results.

Ranking Metrics and Search Guidance for Learning Object Repository

In line with the popularity of the Internet and the development of search engine, users request information through web-based services. Although general-purpose searching such as one provided by Google is powerful, searching mechanism for specific purposes could rely on metadata. In distance learning (or e-learning), SCORM provides an efficient metadata definition for learning objects to be searched and shared. To facilitate searching in a federated repository, CORDRA provides a common architecture for discovering and sharing Learning Objects. We followed SCORM and CORDRA specifications to develop a registry system, called the MINE Registry, for storing and sharing 20,738 Learning Objects created in the past five years. As a contribution, we propose the concept of “Reusability Tree” to represent the relationships among relevant Learning Objects and enhance CORDRA. We further collect relevant information, while users are utilizing Learning Objects, such as citations and time period persisted. The feedbacks from the user community are also considered as critical elements for evaluating significance degree of Learning Objects. Through theses factors, we propose a mechanism to weight and rank Learning Objects in the MINE Registry, in addition to other external learning objects repositories. As a practical contribution, we provide a tool called “Search Guider” to assist users in finding relevant information in Learning Objects based on individual requirements.

Digital inpainting - survey and multilayer image inpainting algorithms

Digital inpainting uses spatial or frequency information to restore partially damaged/removed photos and artworks. Digital image inpainting is an interesting new research topic in multimedia computing and image processing since 2000. This talk covers the most recent contributions in digital image inpainting and image completion, as well as concepts in video inpainting. In addition to a quick survey, the presentation covers several algorithms. Most restoration algorithms consider a picture as a single layer. The talk covers a new approach, which divides a Chinese painting into several layers. Each layer is inpainted separately. A layer fusion mechanism then finds the optimal inpaint among layers, which are restored layer-by-layer. We apply the algorithm on Chinese and western drawing. The result shows a high PSNR value as well as a high user satisfaction. The demonstration of our work is available at :http://www.mine.tku.edu.tw/demos/inpaint.

Video inpainting and implant via diversified temporal continuations

Recent interesting issues in video inpainting are defect removal and object removal. We take one more step to replace the removed objects in a video sequence by implanting objects from another video. Before implant, we improve an exemplar-based image inpainting algorithm by using a new patch matching strategy which incorporates edge properties. The data term used in a priority computation of candidate patches is also redefined. We take varieties of temporal continuations of foreground and background into consideration. A motion compensated inpainting procedure is then proposed. The inpainted video backgrounds are visually pleasant with smooth transitions. A simple tracking algorithm is then used to produce a foreground video, which is implanted into the inpainted background video. Our results are available at http://www.mine.tku.edu.tw/inpainting.

Distributed multimedia databases: techniques & applications

In the last few years we have observed an explosive growth of multimedia computing, communication and applications. This revolution is transforming the way people live, work, and interact with each other, and is impacting the way business, government services, education, entertainment and healthcare are operating. Yet, several issues related to modeling, specification, analysis and design of distributed multimedia database systems and multimedia information retrieval are still challenging to both researchers and practitioners. Distributed Multimedia Databases: Techniques & Applications points out these challenges and provides valuable suggestions toward the necessary solutions, by focusing on multimedia database techniques.

A survey of distance education challenges and technologies

Distance education, e-learning, and virtual university are similar terms for a trend of modern education. It is an integration of information technologies, computer hardware systems, and communication tools to support educational professionals in remote teaching. This chapter presents an overview of distance education from the perspective of policy, people, and technology. A number of questions frequently asked in distance learning panel discussions are presented, with the suggested answers from the authors. The survey presented in this chapter includes communication, intelligent, and educational technologies of distance education. Readers of this 2 Shih, Hung, Ma, and Jin Copyright

Ubiquitous e-Learning With Multimodal Multimedia Devices

The sharable content object reference model (SCORM) is a set of specifications and guidelines for the representation and operation of asynchronous distance learning. Since it was announced in late 1990s, the reference model has been used by software developers and academics in the development of authoring tools, learning management systems, and repositories for distance learning content. To date, most e-learning systems have been based on multimedia and Web technologies on personal computers. Our project, Hard SCORM, advances the field by implementing an integrated system which allows learners to read SCORM-compliant textbooks using multimodal multimedia devices. Hard SCORM employs a pen-like optical character reader device (called Hyper Pen) as an input mechanism. A computer, a personal digital assistant, or a cellular phone can be used for user behavior supervision using the hard SCORM machine. With an authoring tool, specially designed tags are printed in textbooks and recognized by hyper pen for user navigation control. In this way, users can read hardcopy textbooks in a traditional manner while the process of reading conforms to the SCORM specification. Part of the implemented system (Pocket SCORM on PDA) received the 2005 Brandon Hall Excellence in Learning Awards. The system has also been used by an airline company for online security checking and a high school for online mobile learning