6800531
Database Schema Evolution through the Specification and Maintenance of Changes on Entities and Relationships
An information system usually consists of complex application programs structured on top of a database whose schema can change in order to facilitate the needs of new application programs. It is neither easy nor practical to modify the application programs when the database schema is changed. In order to facilitate the needs of new application programs, and to continue supporting existing applications, the database system needs to be able to cope with changing database schemas and maintaining consistency among objects created under different schemas. 
This thesis presents an approach to schema evolution through changes to the Entity-Relationship (ER) schema of a database. In this ER-based approach, changes to a database schema are specified in terms of changes to the ER diagram describing the database. In order to extend ER diagrams for specifying the relationships between an old schema and a new one, corresponding to the one before and the one after change, respectively, a specification language called LEVER and its graphical representation called EVER (EVolutionary ER) diagram were developed. Methods used for mapping the change specifications into the relational and object-oriented data models, for organizing the databases after schema change and for constructing database views for schema versions are described. Through the reconstruction of views after database reorganization, changes to an ER diagram can be made transparent to the application programs while all objects in the database remain accessible to the application programs.
34016873
Parsing 2D Languages by a Pictorial GLR Parser
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.
39945679
Iconic Language Design for People with Significant Speech and Multiple Impairments
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.
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.
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.
44477744
Efficient selection of scheduling rule combination by combining design of experiment and ordinal optimization-based simulation
In a fab with heterogeneous machine groups, the number of scheduling policies grows in a combinatorial way because each machine group has its specific dispatching rules. In this paper, we design a fast simulation methodology by an innovative combination of the notions of ordinal optimization (OO) and design of experiments (DOE) to efficiently select a good scheduling policy for fab operation, Instead of finding the exact performance among scheduling policies, our approach compares their relative orders of performance to a specified level of confidence. The DOE method is exploited to largely reduce the number of scheduling policies to be evaluated by the OO-based simulation. Simulation results of applications to scheduling wafer fabrications show that most of the OO-based DOE simulations require 2 to 3 orders of magnitude less computation time than those of traditional approach, and the speedup is up to 7,000 times in certain cases.
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.
7967901
The effect of machine availability on the worst-case performance of LPT
We consider the makespan minimization parallel machine scheduling problem where each machine may be unavailable for a known time interval. For this problem, we investigate how the worst-case behavior of the longest processing time first algorithm (LPT) is affected by the availability of machines. In particular, for given m machines, we analyze the cases where arbitrary number, λ, ranging from one to m - 1, machines are unavailable simultaneously. Then, we show that the makespan of the schedule generated by LPT is never more than the tight worst-case bound of 1 + ½ ⌊m/(m - λ)⌋ times the optimum makespan.
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.