Mark G. Lee

OCL Constraints Generation from Natural Language Specification

Object Constraint Language (OCL) plays a key role in Unified Modeling Language (UML). In the UML standards, OCL is used for expressing constraints such as well-definedness criteria. In addition OCL can be used for specifying constraints on the models and pre/post conditions on operations, improving the precision of the specification. As a result, OCL has received considerable attention from the research community. However, despite its key role, there is a common consensus that OCL is the least adopted among all languages in the UML. It is often argued that, software practitioners shy away from OCL due to its unfamiliar syntax. To ensure better adoption of OCL, the usability issues related to producing OCL statement must be addressed. To address this problem, this paper aims to preset a method involving using Natural Language expressions and Model Transformation technology. The aim of the method is to produce a framework so that the user of UML tool can write constraints and pre/post conditions in English and the framework converts such natural language expressions to the equivalent OCL statements. As a result, the approach aims at simplifying the process of generation of OCL statements, allowing the user to benefit form the advantages provided by UML tools that support OCL. The suggested approach relies on Semantic Business Vocabulary and Rules (SBVR) to support formulation of natural language expressions and their transformations to OCL. The paper also presents outline of a prototype tool that implements the method.

An Implemented Context System that Combines Belief Reasoning, Metaphor-Based Reasoning and Uncertainty Handling

An implemented context-based reasoning system called ATT-Meta is sketched. The system can perform both reasoning about beliefs of agents and metaphor-based reasoning. In particular, it can perform metaphor-based reasoning about beliefs and reasoning acts. The metaphor-based reasoning and belief reasoning facilities are fully integrated into a general framework for uncertain reasoning. This framework allows for uncertain reasoning and conflict resolution within individual contexts, uncertainty in individual inter-context bridging rules, conflict resolution between the effects of different bridging rules, and conflict-resolution across context boundaries when argumentation inside a context conflicts with argumentation outside.

Transformation rules for translating business rules to OCL constraints

In design of component based applications, the designers have to produce visual such as Unified Modeling Language (UML) models, and describe the software component interfaces. Business rules and constraints are the key components in the skeletons of software components. Semantic of Business Vocabulary and Rules (SBVR) language is typically used to express constraints in natural language and then a software engineer manually maps SBVR business rules to other formal languages such as UML, Object Constraint Language (OCL) expressions. However, OCL is the only medium used to write constraints for UML models but manual translation of SBVR rules to OCL constraints is difficult, complex and time consuming. Moreover, the lack of tool support for automated creation of OCL constraints from SBVR makes this scenario more complex. As, both SBVR and OCL are based on First-Order Logic (FOL), model transformation technology can be used to automate the transformation of SBVR to OCL. In this research paper, we present a transformation rules based approach to automate the process of SBVR to OCL transformation. The presented approach implemented in SBVR2OCL prototype tool as a proof of concept. The presented method softens the process of creating OCL constraints and also assists the designers by simplifying software designing process.

Domain-transcending mappings in a system for metaphorical reasoning

We illustrate how the use of metaphorical views for reasoning with metaphor requires the mapping of information such as event shape, event rate and mental/emotional states from the source domain to the target domain. Such mappings are domain-independent and can be implemented by means of rules we call View Neutral Mapping Adjuncts (VNMAs). We give a list of the main VNMAs that appear to be required, and show how they can be incorporated into a pre-existing system (ATT-Meta) for metaphorical reasoning.

Reasoning in metaphor understanding: the ATT-Meta approach and system

A detailed approach has been developed for core aspects of the task of understanding a broad class of metaphorical utterances. The utterances in question are those that depend on known metaphorical mappings but that nevertheless contain elements not mapped by those mappings. A reasoning system has been implemented that partially instantiates the theoretical approach. The system, called ATT Meta, will be demonstrated. The paper briefly indicates how the system works, and outlines some specific aspects of the system, approach and the overall project.

An ascription-based approach to speech acts

The two principal areas of natural language processing research in pragmantics are belief modelling and speech act processing. Belief modelling is the development of techniques to represent the mental attitudes of a dialogue participant. The latter approach, speech act processing, based on speech act theory, involves viewing dialogue in planning terms. Utterances in a dialogue are modelled as steps in a plan where understanding an utterance involves deriving the complete plan a speaker is attempting to achieve. However, previous speech act based approaches have been limited by a reliance upon relatively simplistic belief modelling techniques and their relationship to planning and plan recognition. In particular, such techniques assume precomputed nested belief structures. In this paper, we will present an approach to speech act processing based on novel belief modelling techniques where nested beliefs are propagated on demand.

Automatic building of Arabic multi dialect text corpora by bootstrapping dialect words

The principle objective of this work is to build multi dialect Arabic texts corpora using a web corpus as a resource. A survey has been conducted to categorize distinct words and phrases that are common to a specific dialect only, and not used in other dialects, the purpose being to download a specific dialect text corpus. From this experiment we obtained 48M tokens from different Arabic dialects. These dialects were categorised into four main dialects Gulf, Levantine, Egyptian and North African, resulting in 14.5M, 10.4M, 13M and 10.1M tokens being obtained respectively. The total number of distinct types in all the corpora is 2M types. In this paper we describe how the corpora were constructed by using distinct words.

Resolving syntactic ambiguities in natural language specification of constraints

In the NL2OCL project, we aim to translate English specification of software constraints to formal constraints such as OCL (Object Constraint Language). In the used approach, the Stanford POS tagger and the Stanford Parser are employed for syntactic analysis of English specification and the output of syntactic analysis is given to our semantic analyzer for the detailed semantic analysis. However, in few cases, the Stanford POS tagger and parser are not able to handle particular syntactic ambiguities in English specifications of software constraints. In this paper, we highlight the identified cases of syntactic ambiguities and we also present a novel technique to automatically resolve the identified syntactic ambiguities. By addressing the identified cases of syntactic ambiguities, we can generate more accurate and complete formal (OCL) specifications.

Multi dialect Arabic speech parallel corpora

This paper describes the building of a multi dialect Arabic speech parallel corpus. It is designed to encompass four main dialects; Modern Standard Arabic (MSA), Gulf, Egypt and Levantine dialects. We have chosen a specific linguistic domain to work with it: travel and tourism. Parallel prompts were written for the four main dialects, which involved 1291 recordings for MSA and 1069 recordings for other dialects. The recordings were conducted with the consent of 52 participants. We have obtained about 32 speech hours. After the segmentation stage, we have obtained a total number of 67,132 speech files. These are the first Arabic parallel texts, and speech corpora and will be an open source for researchers.

End-to-end solution for accessible chemical diagrams

Chemical diagrams are an important means of conveying information in chemistry and biosciences to students, starting as early as secondary school. But even in electronic teaching material, diagrams are commonly given as bitmap graphics leaving them inaccessible for visually impaired learners. We present an end-to-end solution to making these diagrams Web accessible, by employing image analysis solutions to recognise and semantically analyse diagrams, and by regenerating them in a format that makes them amenable to assistive technology. We provide software tools that allow readers to interactively engage with diagrams by exploring them step-wise and on different layers, enabling aural rendering of diagrams and their individual components together with highlighting and magnification to assist readers with low vision or learning difficulties. Our technology builds on open standards, supporting a number of computing platforms, browsers, and screen readers, and is extensible to diagrams in other STEM subjects.