32595686
DAVIC and Interoperability Experiments
To promote the development and deployment of broadband audio visual services, DAVIC has been working on specifying the standards and interfaces for end-to-end systems providing services to consumers over broadband networks. DAVIC specifies tools to provide these broadband services. Since the tools specified by DAVIC are standardized/developed by independent organizations, it is important to verify that the complete system works when these tools are used together. An interoperability event was organized by Columbia University for this very purpose. In this paper we first introduce DAVIC and DAVIC systems and then give details of the interoperability event: the motivation, goals, and results.
15816324
Multi-level specification and protocol design for distributed multimedia communication
The major challenge in the design of an efficient distributed multimedia system is the integration and support of a wide variety of applications. Investigating the basic issues involved in the design and specification of distributed muttimcdia systems is the focus of this paper. A basic layered network architecture is proposed as the uniform framework for the investigation of different levels of functionality typically associated with the communication network that supports multimedia communication. Within this framework, we propose to identify the communication requirements for multimedia applications and characterize a set of communication primitives which specify different qualities of scrvicc to reflect different real-time rcquircmcnts. ‘Ilis investigation is guided by an efficient and flexible multi-level specification model. We will characterize this model and show that the model can be amenable to the construction of a set of communication primitives that support synchronization and communication of multimedia applications.
35519508
Extending Visual Languages for Multimedia
Visual languages, which let users customize iconic sentences, can be extended to accommodate multimedia objects, letting users access media dynamically. Teleaction objects, or multimedia objects with knowledge structures, can be designed using visual languages to automatically respond to events and perform tasks like "find related books" in a virtual library.
17298481
Iconic language design for people with significant speech and multiple impairments
We present an approach of iconic language design for people with significant speech and multiple impairments (SSMI), based upon the theory of Icon Algebra and the theory of Conceptual Dependency (CD) to derive the meaning of iconic sentences. An interactive design environment based upon this methodology is described.
39945679
Iconic Language Design for People with Significant Speech and Multiple Impairments
34016873
Parsing 2D Languages by a Pictorial GLR Parser
15655721
The Worst-case Analysis of the MULTIFIT Algorithm for Scheduling Nonsimultaneous Parallel Machines
Abstract In this paper we consider the nonsimultaneous multiprocessor scheduling problem, or NMSP for short. The NMSP is a makespan minimization scheduling problem which involves the nonpreemptive assignment of independent jobs on m parallel machines with different starting times. It is well known that the longest processing time (LPT) algorithm and the modified LPT(MLPT) algorithm yield schedules with makespans bounded by 3 2 − 1 2m and 4/3 times the optimum makespan, respectively. In this paper, we show that the best known worst-case performance bound, 4/3 of the MLPT, is tight by constructing a worst-case example. Then, we employ the bin-packing heuristic algorithm called the MULTIFIT to solve the NMSP and show that the makespan of the schedule generated by the MULTIFIT algorithm is bounded by 9/7+2−k times the optimum makespan, where k is the selected number of the major iterations in the MULTIFIT. This worst-case bound of the MULTIFIT algorithm is, so far, the best bound for the NMSP and the tightness of the bound is still an open question.
43612588
Priority-Based Internet Access Control for Fairness Improvement and Abuse Reduction
In this paper, we exploit a prioritized-service architecture and apply a priority based traffic control scheme to reduce abusive Internet access, improve fairness among users and study users' behavior under a prioritized service for Internet access. The Internet access by dormitory users of National Taiwan University (NTU) serves as a conveyer problem. There are two classes of service. The regular class has a volume quota for each user, which is designed to meet majority users' essential demands while limiting abusive usage of quality service. The custody class is lower in service priority with no volume quota limitation. Our mathematical models for design and analysis include individual and aggregate user demand models and a network performance model. The priority control scheme is implemented over an existing NTU dormitory network with additions of a QoS router, a meter reading server, an accounting server and a user interface server. The control leads to 48.9% reduction in average packet drop rate, 42.2% improvement in a fairness measure, reduction of abusive Internet access by 57.82% and 145.09% Internet access increase in majority users. Such results are quite consistent with predictions of our mathematical models.
20494586
The implementation of a secure and pervasive multimodal Web system architecture
While most users currently access Web applications from Web browser interfaces, pervasive computing is emerging and offering new ways of accessing Internet applications from any device at any location, by utilizing various modes of interfaces to interact with their end users. The PC and its back-end servers remain important in a pervasive system, and the technology could involve new ways of interfacing with a PC and/or various types of gateways to back-end servers. In this research, cellular phone was used as the pervasive device for accessing an Internet application prototype, a multimodal Web system (MWS), through voice user interface technology. This paper describes how MWS was developed to provide a secure interactive voice channel using an Apache Web server, a voice server, and Java technology. Securing multimodal applications proves more challenging than securing traditional Internet applications. Various standards have been developed within a context of Java 2 Micro Edition (J2ME) platform to secure multimodal and wireless applications. In addition to covering these standards and their applicability to the MWS system implementation, this paper also shows that multimodal user-interface page can be generated by using XSLT stylesheet which transforms XML documents into various formats including XHTML, WML, and VoiceXML.
44449006
Online and semi-online scheduling of two machines under a grade of service provision
We consider the online scheduling of two machines under a grade of service (GoS) provision and its semi-online variant where the total processing time is known. Respectively for the online and semi-online problems, we develop algorithms with competitive ratios of 53 and 32 which are shown to be optimal.
7920215
The design of a secure and pervasive multimodal Web system
While most users currently receive Web services from Web browser interfaces, pervasive computing is emerging and offering new ways of accessing Internet applications from any device at any location (Satyanarayanan, 2002; Estrin et al., 2002), by utilizing various modes of interfaces to interact with their end users. The PC and its back-end servers remain important in a pervasive system, and the technology could involve new ways of interfacing with a PC and/or various types of gateways to back-end servers. In this research, cellular phone was used as the pervasive device for accessing an Internet application prototype, a multimodal Web system (MWS), through voice user interface technology (Anerousis and Panagos, 2002). This paper describes how MWS was designed to provide a secure interactive voice channel using an Apache Web server, a voice server, and a Java servlet engine. It was also shown that multimodal user-interface pages can be generated by using XSLT stylesheet which transforms XML documents into various formats including XHTML, WML, and VoiceXML.