Technically, because of the limited dimensions of the presentation media, and psychologically, because of the limited human attention span, graphical program visualization in computer assisted reverse engineering becomes increasingly difficult with scale. This problem becomes compounded when multi-perspective visualization is taken into consideration. In this research we present a system called HVIEW, which attempts to overcome the problem of scale by logical decomposition. HVIEW can present a graphical visual of a computer program at various abstraction levels from diverse perspectives as interactively requested by the user. HVIEW logically formulates abstract function and data objects to construct compressed immediate program representations and organizes them into independent data and function hierarchies. Whereas, these hierarchies provide the mechanism of flexible abstraction, a user specifiable query filter creates an assortment of perspectives on the rendered visual of the modelled code.>

This paper presents a rule-based tool MG (Model Generator) for reverse engineering from source code to graphical models. For a given graphical model formalism, generation rules describe how to translate each primitive element (e.g., an if statement) of a programming language into a piece of a diagram in the graphical model and how to assemble the produced pieces of diagrams and generate diagrams from them. MG can produce software specification in different models by changing the generation rules. This feature enables maintainers to obtain the information they need by specifying rules for generating it. MG is also independent of programming languages. It is used to generate four models and links between them from COBOL source code, where each model represents a coherent aspect of the source code such as control flow and functional structure.>

This paper presents an automatic layout tool which applies fuzzy theory to rule-based layout of diagrams in graphical models. MERA (Meta-Entity-Relation-Attribute) is used as a uniform language for various graphical models used in requirements and design specifications of software. A unique feature of the tool is that a layout of a diagram in a graphical model is produced, based on the layout rules implied by semantics of the diagram and the model formalism. Another unique feature of the tool is that layout rules for a graphical model can automatically be generated from layout examples given by users. The examples of a diagram layout can be regarded as stereotypes of the diagram layout for the model. A prototype of the automatic layout tool has been implemented in SUN Common Lisp using CLOS.>

MERA (Meta Entity-Relation-Attribute) is a versatile graphical language which can be used for modeling and analysis of the user requirements, for building a prototype, for representing designer's knowledge for controlling design process, etc. The current version of MERA has capacity for animation, view operation, user adaptability, and some semantic level processing. It also contains dozens of modeling formalisms which were created to support various tasks in the software engineering practice. The authors have created many tools to support the MERA language including a syntax-driven graph editor, user interface simulator, requirements analysis and prototyping environments, methodology adaptable design environment, requirements interview system and program understanding system. This paper presents the important features of the MERA language and MERA based software engineering tools.>

This paper presents a comprehensive set of hierarchically organized synthetic models developed for the performance evaluation of data base management systems. The first set of algebraic models for data base management system itself contains a program behavior model, a retrieval model, a logical data base model, a physical data base model, and a data processing model. These models are intended to clarify logical and physical data base structures and essential operations in the data processing on them. Another set of models for performance analysis contains a macroscopic program behavior model, a storage model, a processor model, a user behavior model, and an interactive model. In this set this paper is particularly concerned with the first 3 models. The macroscopic program behavior model is based on the discussion of data locality and allows us to estimate the frequency of data page loading expected on a given application program and a data base. The storage model enables us to estimate the traverse time of data page loading. Finally the processor model allows us to evaluate the data retrieval processing time of data manipulation commands of a given data base structure, a data base management system and a set of application programs under the multiprogramming environment. These models are to be applied to the optimization of the application programs or the data base structure in order to obtain a higher data retrieval performance.