Guanglei Song

Multimedia layout adaptation through grammatical specifications

Abstract.Online multimedia presentations, such as news, need to be constantly updated. Increasing demands are also being made for accessing online multimedia documents from mobile devices such as PDAs. There is an urgent need for a sound but practical formalism that supports automatic adaptation to the change of media content, display environments, and user intention. This paper presents a visual language approach to the layout adaptation of multimedia objects. The underlying theory of our approach is a context-sensitive graph grammar formalism enriched with facilities for spatial representation and specification. The paper focuses on the issues and techniques for size adaptation and style adaptation in response to the change of device requirements and user interactions.

A graph grammar approach to software architecture verification and transformation

Software architecture and design are usually modeled and represented by informal diagrams, such as architecture diagrams and UML diagrams. While these graphic notations are easy to understand and are convenient to use, they are not amendable to automated verification and transformation. This paper provides graph grammars for architecture and UML class diagrams. These grammars enable a high level of abstraction for the general organization of a class of software architectures, and form a basis for various analysis and transformations. In this approach, software verification is performed through a syntax analyzer. Architecture transformation is achieved by applying predefined transformation rules.

Model Management Through Graph Transformation

Model management offers a higher level interface than current techniques for metadata management, and generic operators drastically reduce amount of programming for metadata applications. The interactive nature of generic model management operators inevitably demands an intuitive representation. This paper proposes a visual representation for model management operators based on graph transformation. Graph transformation formalisms, as the theoretic foundation of many visual programming languages, can formally represent model management operators by visual and intuitive expressions. By using graphical representations, users can easily comprehend and manipulate the operators and desired outputs

Visual XML schemas based on reserved graph grammars

This paper presents a Visual XML schema based on a graph grammar formalism. The visual approach is intuitive in describing the syntax and semantics of an XML document, and provides a visual framework for users to edit and validate XML schema visually. This paper also presents a parsing algorithm for the visual schema, whose time complexity is polynomial.

A Generative Style-driven Framework for Software Architecture Design

Compared with texts, graphs are more intuitive to express comparative and structural information. Many graphical approaches, however, lack a formal basis for precise specifications in the design. This paper proposes a generative style-driven framework for software architecture specification based on a visual language formalism. In this framework, the designer uses graphical notations to define architectural styles. Given the graphical specifications, a visual language generator, i.e. a meta-tool, can automatically generate a specific design environment, which is suitable for the users without any knowledge of formal methods to directly manipulate software architectures by drawing box-line graphs. The graph transformation engine underlying the design environment can automatically validate structural integrity and reveal the hierarchical structure of a user-defined software architecture

Oasis: A Mapping and Integration Framework for Biomedical Ontologies

More and more ontologies are emerging across bioinformatics domains to represent and define domain knowledge, such as gene ontology, anatomy ontology and disease ontology. To integrate these heterogeneous ontologies is becoming critically important for applications utilizing multiple ontologies. Because the entities described in the ontology often overlap with other entities in other ontologies, a mapping between two corresponding terms is required and becoming the key to the integration of heterogeneous ontologies. Based on a previously developed schema matching algorithm, this paper presents a framework for mapping and integration of heterogeneous biomedical ontologies. The framework detects possible false mappings intelligently and provides intuitive interfaces for users to customize mappings and for applications to integrate and access biomedical ontologies

Management of Web Data Models Based on Graph Transformation

Based on the Reserved Graph Grammar (RGG), this paper presents a unified framework to manage model-based information on the Web in a hierarchical structure. The framework allows models, schemas, and data instances to be represented explicitly and uniformly. The uniform representation of the framework also enables simple user-defined graph transformation rules for different Web data models to translate schemas and data instances between different formats. In addition, the framework implements a set of prototype tools for users to identify meta-primitives at the meta-model level, to define a model or schema by specifying a set of graph grammar rules and to draw the structure of data instances. These features promote a wide scope of Web-related applications, such as information exchange between different organizations, and integration of data coming from heterogeneous information sources.

AutoGen: Easing model management through two levels of abstraction

Due to its extensive potential applications, model management has attracted many research interests and gained great progress. To provide easy-to-use interfaces, we have proposed a graph transformation-based model management approach that provides intuitive interfaces for manipulation of graphical data models. The approach consists of two levels of graphical operators: low-level customizable operators and high-level generic operators, both of which consist of a set of graph transformation rules. Users need to program or tune the low-level operators for desirable results. To further improve the ease-of-use of the graphical model management, automatic generation of low level of operators is highly desirable. The paper formalizes specifications of low- and high-level operators and proposes a generator to automatically transform high-level operators into low-level operators upon specific input data models. Based on graph transformation theoretical foundation, we design an algorithm for the generator to automatically produce low-level operators from input data models and mappings according to a high-level operator. The generator, called AutoGen, therefore eliminates many tedious specifications and thus eases the use of the graphical model management system.

Towards access control for visual Web model management

With the advance of e-commerce over Web-based information, the interoperability of isolated XML repositories and databases over the Internet has drawn an increasing interest recently. Little effort, however, has been made to preserve necessary autonomy and security of each individual XML repository or database during information exchange or evolution. Generic model management has been intensively researched and also implemented in a prototype since its first introduction. Security related research is yet to be conducted for model management. This paper presents a uniform security model for access control specifications of heterogeneous data models over the Web. Based on the uniform representation, we present security extensions to our previous work on visual model management operators for managing access control specifications to allow heterogeneous Web data models to exchange information over public networks.

Secure model management operations for the web

The interoperability among different data formats over the Internet has drawn increasing interest recently due to more and more heterogeneous data models are used in different Web services. In order to ease the manipulation of data models for heterogeneous data, generic model management has been intensively researched and also implemented in a prototype since its first introduction. Access control specifications attached to each individual data model require significant amount of efforts to manually specify. Based on a general security model for access control specifications on heterogeneous data models and its visual representation, we present secure model management operators for managing access control specifications.The secure model management operators disccussed in the paper include a secure match operator and a secure merge operator. We introduce a novel graphical schema matching algorithm and extend the algorithm to make a secure match operator. The paper also discusses secure merge principles for the integration of data models.