Confluent Orthogonal Drawings of Syntax Diagrams

We provide a pipeline for generating syntax diagrams (also called railroad diagrams) from context free grammars. Syntax diagrams are a graphical representation of a context free language, which we formalize abstractly as a set of mutually recursive nondeterministic finite automata and draw by combining elements from the confluent drawing, layered drawing, and smooth orthogonal drawing styles. Within our pipeline we introduce several heuristics that modify the grammar but preserve the language, improving the aesthetics of the final drawing.Comment: GD 201

Refining Transformation Rules For Converting UML Operations To Z Schema

The UML (Unified Modeling Language) has its origin in mainstream software engineering and is often used informally by software designers. One of the limitations of UML is the lack of precision in its semantics, which makes its application to safety critical systems unsuitable. A safety critical system is one in which any loss or misinterpretation of data could lead to injury, loss of human lives and/or property. Safety Critical systems are usually specified by very precisely and frequently required formal verification. With the continuous use of UML in the software industry, there is a need to augment the informality of software models produced to remove ambiguity and inconsistency in models for verification and validation. To overcome this well-known limitation of UML, formal specification techniques (FSTs), which are mathematically tractable, are often used to represent these models. Formal methods are mathematical techniques that allow software developers to produce softwares that address issues of ambiguity and error in complex and safety critical systems. By building a mathematically rigorous model of a complex system, it is possible to verify the system\u27s properties in a more thorough fashion than empirical testing. In this research, the author refines transformation rules for aspects of an informally defined design in UML to one that is verifiable, i.e. a formal specification notation. The specification language that is used is the Z Notation. The rules are applied to UML class diagram operation signatures iteratively, to derive Z schema representation of the operation signatures. Z representation may then be analyzed to detect flaws and determine where there is need to be more precise in defining the operation signatures. This work is an extension of previous research that lack sufficient detail for it to be taken to the next phase, towards the implementation of a tool for semi-automated transformation

A systematic approach to atomicity decomposition in Event-B

Event-B is a state-based formal method that supports a refinement process in which an abstract model is elaborated towards an implementation in a step-wise manner. One weakness of Event-B is that control flow between events is typically modelled implicitly via variables and event guards. While this fits well with Event-B refinement, it can make models involving sequencing of events more difficult to specify and understand than if control flow was explicitly specified. New events may be introduced in Event-B refinement and these are often used to decompose the atomicity of an abstract event into a series of steps. A second weakness of Event-B is that there is no explicit link between such new events that represent a step in the decomposition of atomicity and the abstract event to which they contribute. To address these weaknesses, atomicity decomposition diagrams support the explicit modelling of control flow and refinement relationships for new events. In previous work,the atomicity decomposition approach has been evaluated manually in the development of two large case studies, a multi media protocol and a spacecraft sub-system. The evaluation results helped us to develop a systematic definition of the atomicity decomposition approach, and to develop a tool supporting the approach. In this paper we outline this systematic definition of the approach, the tool that supports it and evaluate the contribution that the tool makes

ISML: an interface specification meta-language

In this paper we present an abstract metaphor model situated within a model-based user interface framework. The inclusion of metaphors in graphical user interfaces is a well established, but mostly craft-based strategy to design. A substantial body of notations and tools can be found within the model-based user interface design literature, however an explicit treatment of metaphor and its mappings to other design views has yet to be addressed. We introduce the Interface Specification Meta-Language (ISML) framework and demonstrate its use in comparing the semantic and syntactic features of an interactive system. Challenges facing this research are outlined and further work proposed

Toward an isomorphic diagram of the Backus-Naur form.

Computer scientists studying formal languages have made use of a variety of representations to both reason, and communicate their ideas to others. Symbolic representations have proved useful for rigorously defining the theoretical objects of the preceding topics; however, research shows that diagrammatic representations are as fundamental to these subjects. Previous research in this domain has typically been interested in studying the semantics that a particular representation is intended to capture. By contrast, this treatise considers the importance of the format of the representations themselves, and how format influences the ability of a person to uncover characteristics, relevant to the problem domain. More specifically, this thesis investigates the established formalisms that have been devised to describe formal languages, and introduces a novel concept, an augmented syntax graph. This graph, an isomorphism of the Backus-Naur form, is shown to have application in visualizing properties that are pertinent to some parsing algorithms

Standard CGIF interoperability in Amine

The adoption of standard CGIF by CG tools will enable interoperability between them to be achieved, and in turn lead to the interoperability between CG tools and other tools. The integration of ISO Common Logic’s standard CGIF notation in the Amine platform is presented. It also describes the first steps towards full interoperability between the Amine CG tool (through its Synergy component) and CharGer, a representative CG tool that supports similar interoperability and for process (or ‘active’) knowledge as well as declarative knowledge. N-adic relations are addressed as well as semantic compatibility across the two tools. The work remarks on the successes achieved, highlighting certain issues along the way, and offering a real impetus to achieve interoperability.</p

Design and development of protocol log analyzer for cellular modem

Abstract. Telecommunications protocols and cellular modems are used in devices to facilitate wireless communication. Cellular modems produce log files, which have to be analyzed by engineers when issues occur. Performing the analysis for large logs manually can be very time consuming, thus different approaches for trying to automate or simplify the process exist. This thesis presents design and development for a cellular modem log analysis tool. The tool is designed to take into account peculiarities of telecommunications protocols and cellular modems, especially of 5G New Radio Radio Resource Control protocol. A notation for defining analysis rules used by the tool is presented to be used alongside the tool. The developed tool is a proof-of-concept, with focus being on how the tool performs the analysis and how the notation can be used to define the wanted analysis rules. The features of the notation include defining expected content of protocol messages and order of log message sequences. The tool performs well with artificial modem logs, though some flaws in the notation are recognized. In the future, the tool and the notation should be updated with support for real cellular modem logs and evaluated in field use cases by cellular modem engineers.Matkapuhelinmodeemien lokitiedostojen analysointityökalun suunnittelu ja toteutus. Tiivistelmä. Tietoliikenneprotokollia ja matkapuhelinmodeemeja käytetään laitteissa langattoman tiedonsiirron mahdollistamiseksi. Matkapuhelinmodeemit tuottavat lokitiedostoja, joita insinöörien täytyy analysoida ongelmatilanteissa. Suurten lokitiedostojen analysointi manuaalisesti on työlästä, joten on olemassa keinoja prosessin automatisointiin tai yksinkertaistamiseen. Tämä työ esittelee suunnitelman ja toteutuksen matkapuhelinmodeemin lokitiedostojen analysointityökalulle. Työkalun suunnittelussa on otettu huomioon tietoliikenneprotokollien, erityisesti 5G New Radion radioresurssien hallintaprotokollan (RRC), ja matkapuhelinmodeemien erikoisuudet. Merkintäsäännöstö, jolla voidaan määritellä analyysisäännöt, esitellään työkalulle. Kehitetty työkalu on karkea prototyyppi. Kehityksessä keskitytään työkalun analyysiominaisuuksiin ja mahdollisuuksiin käyttää merkintäsäännöstöä määrittämään halutut analyysisäännöt. Merkintäsäännöstön ominaisuuksiin kuuluu odotettujen lokiviestien sisällön ja järjestyksen määrittely. Työkalu suoriutuu keinotekoisien modeemilokitiedostojen kanssa hyvin, mutta joitain vikoja merkintäsäännöstöstä havaittiin. Tulevaisuuden kehitystä ajatellen työkalu kannattaisi päivittää toimimaan aitojen matkapuhelinmodeemien lokitiedostojen kanssa, että sen kykyä suoriutua aidoista käyttötilanteista voitaisiin arvioida

The Python user interface of the elsA cfd software: a coupling framework for external steering layers

The Python--elsA user interface of the elsA cfd (Computational Fluid Dynamics) software has been developed to allow users to specify simulations with confidence, through a global context of description objects grouped inside scripts. The software main features are generated documentation, context checking and completion, and helpful error management. Further developments have used this foundation as a coupling framework, allowing (thanks to the descriptive approach) the coupling of external algorithms with the cfd solver in a simple and abstract way, leading to more success in complex simulations. Along with the description of the technical part of the interface, we try to gather the salient points pertaining to the psychological viewpoint of user experience (ux). We point out the differences between user interfaces and pure data management systems such as cgns