OSU : integrating CASE and UIMS

Oregon Speedcode Universe (OSU) is a software development environment for design, implementation, and maintenance of large soft.ware systems. Designed to be highly visual, OSU combines traditional structured analysis techniques found in most CASE tools with advanced graphical user interface management systems (UIMS) found on most contemporary workstations. This paper describes the design and implementation of four unique features of OSU: 1) combination of functional decomposition with object-oriented design, 2) alternate architectural views, e.g. call graph. uses graph, object graph, and graphical display of procedures, 3) program understanding tools for design and maintenance, and 4) merging the user interface specification with design and coding specifications.KEYWORDS: CASE, prototyping, object-oriented design, structured analysis, hierarchical decomposition, visual programming, graphical user interface, user interface management, software specification, software design

Using Specification and Description Language to define and implement discrete simulation models

The formal languages become important tools since they allow the complete understanding of the model and help in its implementation. However only a few simulation tools allow an automatic execution of a simulation model based in a formalization of the system. Specification and Description Language is a modern object oriented graphical formal language that allows the definition of distributed systems. It has focused on the modeling of reactive, state/event driven systems, and has been standardized by the International Telecommunications Union (ITU) in the Z.100. Since it is a graphical formalism simplifies the understanding of the model. In this paper we show how we can use Specification and Description Language to represent a discrete simulation model. We propose a solution, implemented in SDLPS, regarding how to manage the time in Specification and Description Language. Also, we show how SDLPS infrastructure allows a distribute simulation of the models.Postprint (published version

A distributed object-oriented graphical programming system

technical reportThis report presents the design of a distributed parallel object system (DPOS) and its implementation using a graphical editing interface. DPOS brings together concepts of object-oriented programming and graphical programming with aspects of modern functional languages. Programs are defined as networks of active processes called "Process Objects" and interconnecting communications lines. These active objects are independent single threaded programs that employ much of the modularity, encapsulation of function, and encapsulation of data found in sequential object-oriented programming. The system defines a clear and simple approach to generating and managing parallelism and interprocess communication in a distributed parallel environment. DPOS contributes several new solutions to the problems of distributed parallel programming that are improvements over existing systems. The key improvements of this system include: a more complete and versatile means of dynamic process creation; the specification of complex network topologies in an intuitively clear and understandable way; seperation of the management of parallelism from the definition of computation; automatic resolution of low level critical section issues; the ability to design and develop separate processes as traditional single threaded programs; the encapsulation and incremental development of programs subnetworks; application of graphical programming concepts to high level programming

Advanced techniques in reliability model representation and solution

The current tendency of flight control system designs is towards increased integration of applications and increased distribution of computational elements. The reliability analysis of such systems is difficult because subsystem interactions are increasingly interdependent. Researchers at NASA Langley Research Center have been working for several years to extend the capability of Markov modeling techniques to address these problems. This effort has been focused in the areas of increased model abstraction and increased computational capability. The reliability model generator (RMG) is a software tool that uses as input a graphical object-oriented block diagram of the system. RMG uses a failure-effects algorithm to produce the reliability model from the graphical description. The ASSURE software tool is a parallel processing program that uses the semi-Markov unreliability range evaluator (SURE) solution technique and the abstract semi-Markov specification interface to the SURE tool (ASSIST) modeling language. A failure modes-effects simulation is used by ASSURE. These tools were used to analyze a significant portion of a complex flight control system. The successful combination of the power of graphical representation, automated model generation, and parallel computation leads to the conclusion that distributed fault-tolerant system architectures can now be analyzed

Towards a representation of environmenal models using specification and description language: from the fibonacci model to a wildfire model

In this paper we explore how we can use Specification and Description Language (SDL) to represent environmental models. Since the main concern in this kind of models is the representation of the geographical information data, we analyze how we can represent this information in the SDL diagrams. We base our approach using two examples, a representation of the Fibonacci function using a cellular automaton, and the representation of a wildfire model. To achieve this we propose the use of a language extension to Specification and Description Language. This allows the simplification of the representation of cellular automatons. Thanks this we can define the behavior of environmental models in a graphical way allowing its complete and unambiguous description. SDL is a modern object oriented formalism that allows the definition of distributed systems. It has focused on the modeling of reactive, state/event driven systems, and has been standardized by the International Telecommunications Union (ITU) in the Z.100.Postprint (published version

Representing Fibonacci function through cellular automata using specification and description language

In this poster we show how to use Specification and Description Language (SDL) to represent cellular automata models. To achieve that we use a generalization of the common cellular automata, named m:n-$CA^k$. Also we add some extension to SDL language to simplify the representation of these automata. Thanks to SDL and m:n-$CA^k$ the behavior of the cellular automata model can be defined in a graphical way allowing the complete and unambiguous description of the simulation model that uses it. SDL is a modern object oriented language that allows the definition of distributed systems. It has focused on the modeling of reactive, state/event driven systems, and has been standardized by the International Telecommunications Union (ITU) in the Z.100.Postprint (published version

Development of a client interface for a methodology independent object-oriented CASE tool : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Computer Science at Massey University

The overall aim of the research presented in this thesis is the development of a prototype CASE Tool user interface that supports the use of arbitrary methodology notations for the construction of small-scale diagrams. This research is part of the larger CASE Tool project, MOOT (Massey's Object Oriented Tool). MOOT is a meta-system with a client-server architecture that provides a framework within which the semantics and syntax of methodologies can be described. The CASE Tool user interface is implemented in Java so it is as portable as possible and has a consistent look and feel. It has been designed as a client to the rest of the MOOT system (which acts as a server). A communications protocol has been designed to support the interaction between the CASE Tool client and a MOOT server. The user interface design of MOOT must support all possible graphical notations. No assumptions about the types of notations that a software engineer may use can be made. MOOT therefore provides a specification language called NDL for the definition of a methodology's syntax. Hence, the MOOT CASE Tool client described in this thesis is a shell that is parameterised by NDL specifications. The flexibility provided by such a high level of abstraction presents significant challenges in terms of designing effective human-computer interaction mechanisms for the MOOT user interface. Functional and non-functional requirements of the client user interface have been identified and applied during the construction of the prototype. A notation specification that defines the syntax for Coad and Yourdon OOA/OOD has been written in NDL and used as a test case. The thesis includes the iterative evaluation and extension of NDL resulting from the prototype development. The prototype has shown that the current approach to NDL is efficacious, and that the syntax and semantics of a methodology description can successfully be separated. The developed prototype has shown that it is possible to build a simple, non-intrusive, and efficient, yet flexible, useable, and helpful interface for meta-CASE tools. The development of the CASE Tool client, through its generic, methodology independent design, has provided a pilot with which future ideas may be explored