Assessing composition in modeling approaches

Modeling approaches are based on various paradigms, e.g., aspect-oriented, feature-oriented, object-oriented, and logic-based. Modeling approaches may cover requirements models to low-level design models, are developed for various purposes, use various means of composition, and thus are difficult to compare. However, such comparisons are critical to help practitioners know under which conditions approaches are most applicable, and how they might be successfully generalized and combined to achieve end-to-end methods. This paper reports on work done at the 2nd International Comparing Modeling Approaches (CMA) workshop towards the goal of identifying potential comprehensive modeling methodologies with a particular emphasis on composition: (i) an improved set of comparison criteria; (ii) 19 assessments of modeling approaches based on the comparison criteria and a common, focused case study

Improving the Specification of Business Application Requirements Based on Executable Models

Istraživanje predstavljeno u okviru ove disertacije imalo je za cilj unapređenje procesa specifikacije korisničkih zahteva poslovnih aplikacija na bazi detaljnih, izvršivih prototipova koji se mogu kreirati uz minimalan utrošak vremena i energije. Radi postizanja ovog cilja je implementiran alat otvorenog koda pod nazivom Kroki (fr. croquis – skica) čija je arhitektura projektovana tako da obezbedi: (1) kolaborativni razvoj specifikacije poslovne aplikacije sa korisnicima koji nemaju znanje projektovanja i programiranja softverskih sistema, (2) efikasno pokretanje prototipa direktno iz sopstvenog razvojnog okruženja, dajući mogućnost korisniku da isproba prototip tokom modelovanja kad god poželi, (3) ponovno korišćenje informacija dobijenih prilikom razvoja prototipova u kasnijim fazama razvoja, kako bi se smanjilo nepotrebno trošenje resursa. Eksperiment za proveru da li razvijeni alat zadovoljava postavljene ciljeve je dizajniran kao serija od deset eksplorativnih studija slučaja čiji je cilj specifikacija poslovnih aplikacija sa učesnicima koji dolaze iz različitih poslovnih domena koji nisu poznati projektantima. Pojedinačne studije su obavljene sa po jednim učesnikom u okviru dvočasovnih projektantskih sesija, gde su ulogu projektanata imali autor ove disertacije i njegov mentor. Kvalitativni i kvantitativni podaci prikupljeni tokom sesija i posle njih, putem upitnika, su iskorišćeni za izvođenje pozitivnih zaključaka o efikasnosti predloženog pristupa i alata. Dizajn istraživanja je baziran na konceptima MEM-a (Method Evaluation Model) koji definiše kriterijum za uspeh određene metodologije u praksi. Upitnici koji evaluiraju jezik za modelovanje i Kroki alat su formulisani tako da odgovaraju izabranim konceptima FQUAD (Framework for qualitative assessment of domain-specific languages) okvira za evaluaciju jezika specifičnih za domen.The research presented in this dissertation aimed to improve the process of specification of user requirements of business applications based on detailed, executable prototypes that can be created with minimal expenditure of time and energy. To achieve this goal, an open-source tool called Kroki (fr. croquis - sketch) was implemented, the architecture of which is designed to provide: (1) Collaborative development of business application specifications with users who do not have knowledge of designing and programming software systems, (2) Efficient prototyping directly from Kroki’s development environment, enabling the user to try out the prototype during modeling whenever they want, and (3) Reuse of information obtained during the development of prototypes in later stages of development, to reduce unnecessary consumption of time and energy. The experiment to validate whether the developed Kroki tool meets the set goals was designed as a series of ten exploratory case studies to specify business applications with participants from different business domains unknown to the designers. Individual studies were carried out within two-hour design sessions, where the author of this dissertation and his mentor played the designer role, with a single participant in the user role in each session. Qualitative and quantitative data collected during and after the sessions, through questionnaires, were used to draw positive conclusions about the effectiveness of the proposed approach and tools. The research design is based on the concepts of MEM (Method Evaluation Model), which defines the criteria for the success of a certain methodology in practice. Questionnaires that evaluate the modeling language and the Kroki tool are formulated to correspond to the selected concepts of the FQUAD (Framework for qualitative assessment of domain-specific languages) for evaluating DSLs

Borehole water level response to barometric pressure as an indicator of aquifer vulnerability

The response of borehole water levels to barometric pressure changes in semiconfined aquifers can be used to determine barometric response functions from which aquifer and confining layer properties can be obtained. Following earlier work on barometric response functions and aquifer confinement, we explore the barometric response function as a tool to improve the assessment of groundwater vulnerability in semiconfined aquifers, illustrated through records from two contrasting boreholes in the semiconfined Chalk Aquifer, East Yorkshire, UK. After removal of recharge and Earth tide influences on the water level signal, barometric response functions were estimated and aquifer and confining layer properties determined through an analytical model of borehole water level response to barometric pressure. A link between the thickness and vertical diffusivity of the confining layer determined from the barometric response function, and groundwater vulnerability is proposed. The amplitude spectrum for barometric pressure and instrument resolution favor determination of the barometric response function at frequencies to which confining layer diffusivities are most sensitive. Numerical modeling indicates that while the high frequency response reflects confining layer properties in the immediate vicinity of the borehole, the low frequency response reflects vertical, high diffusivity pathways though the confining layer some hundreds of meters distant. A characteristic time scale parameter, based on vertical diffusivities and thicknesses of the saturated and unsaturated confining layer, is introduced as a measure of semiconfined aquifer vulnerability. The study demonstrates that the barometric response function has potential as a tool for quantitative aquifer vulnerability assessment in semiconfined aquifers

BSML-mbeddr: Integrating Semantically Congurable State-Machine Models in a C Programming Environment

In model-driven engineering, developers express their solutions in domain-specific modelling languages (DSLs) that support domain-specific abstractions. Big-Step Modelling Languages (BSML) is a family of extended state-machine DSLs for creating executable models that have a complex execution semantics. In this paper, we present BSML-mbeddr, which imbeds a large subset of BSML within the mbeddr C programming environment, thereby extending mbeddr with language constructs for extended, semantically configurable state-machines. We also report on three case studies that exercise the expressiveness of BSML-mbeddr, assess the integrability of BSML-mbeddr into mbeddr, and demonstrate the need to provide support for state-machine models with different execution semantics.NSERC Discovery Grant, 155243-12 || Ontario Research Fund, RE05-04

Type theory as a framework for modelling and programming

In the context provided by the proceedings of the UVMP track of ISoLA 2016, we propose Type Theory as a suitable framework for both modelling and programming. We show that it fits most of the requirements put forward on such frameworks by Broy et al. and discuss some of the objections that can be raised against it

DASH: Declarative Modelling with Control State Hierarchy (Preliminary Version)

We present a new language, called DASH, for describing formal behavioural models. DASH combines common modelling constructs to describe abstractly both data and control in an integrated manner. DASH uses the Alloy language for describing data and its operations declaratively, and adds syntax for labelled control state hierarchy common in Statecharts descriptions of transition systems. In addition, DASH accommodates multiple factoring paradigms for modelling (control states, events, and conditions) and includes syntactic sugar (e.g., transition comprehension, transition templates) to write models that are concise and easy to understand. We describe the formal semantics of DASH, which carefully mix the usual semantic understanding of control state hierarchy with the declarative perspective, for creating abstract models early in system development. We implement these semantics in a translator from DASH to Alloy taking advantage of Alloy language features. We demonstrate DASH, our tool, and model checking analysis in the Alloy Analyzer using several case studies. The key novel insight of our work is in combining seamlessly common data and control modelling paradigms in a way that will be intuitive for those used to either paradigm, and enabling automatic analysis of the integrated model