DT4BP: a Business Process Modelling Language for Dependable Time-Constrained Business Processes

Today, numerous organisations rely on information software systems to run their businesses. The effectiveness of the information software system then, depends largely on the degree to which the organisation's business is accurately captured in the business model. The business model is an abstract description of the way an organisation's functions. Thus, the more precise the business model, the more accurate the requirement definition of the information software system to be engineered.There are an abundance of tools and notations available today to support the development of many types of business process. Many of these artifacts rely on the concept of a business process to describe a business model. A business process is commonly known as a set of one or more linked procedures or activities which collectively realise a business objective or policy goal, normally within the context of an organisational structure defining functional roles and relationships". This thesis is concerned with modelling business processes as a means to accurately capture an organisation's activities and thus, the requirements of the software system that supports these activities.Among the infinite set of possible business processes, this thesis targets only those characterized by the qualities of dependability, collaboration and time. Business processes having these specific dimensions are referred to as Dependable, Collaborative and Time-Constrained (DCTC) business processes. A dependable business process is one whose failures or the number of occurrences in which business process misses its goal are not unacceptably frequent or severe (from certain viewpoint). A collaborative business process is one that requires the interaction of multiple participants to attain its goal. A time-constrained business process is one that owns at least one property expressed in terms of an upper or lower time bound. This thesis investigates how DCTC business processes can be described such that the resulting model captures all the relevant aspects of each dimension of interest. In addition, the business model must be comprehensible to the stakeholders involved not only in its definition, but also in its further use throughout the software development life cycle.A revision and analysis of notations that exist for modelling business processes conducted in this thesis have revealed that today there does not exist any modelling language that provides comprehensible, suitable and sufficiently expressive support for the characteristics of dependability, collaboration and time in an integrated manner. Hence, a significant part of this thesis is devoted to the definition of a new business process modelling language named DT4BP. The aim of this new modelling language is to be comprehensible, suitable and expressive enough to describe DCTC business processes. The definition of this new modelling language implies that a concrete syntax, an abstract syntax, a semantic domain and a semantic mapping is provided. The definition of this new modelling language is given following the Model-Driven Engineering (MDE) approach, and in particular the metamodelling principles. Thus, meta-models and model transformations are used to precisely specify the abstract syntax and semantic mapping elements of the language definition, respectively. Since DT4BP is a textual modelling language, its concrete syntax is specified by a context-free grammar. The Coordinated Atomic Actions conceptual framework with real-time extensions (Timed-CaaFWrk) is used as the semantic domain as it covers a large part of the abstractions included in dependable collaborative time-constrained business processes. The formalisation of this semantic domain according to the metamodelling principles is also part of the material presented in this thesis. Since the business model is considered as a representation of the requirement document the software system to be developed, it is crucial to validate whether it captures the requirements as intended by the stakeholder before going further in the software development process. Hence, besides the comprehensibility, suitability and expressiveness of the modelling language with respect to the domain of interest, it is of special interest to provide a mechanism that allows modellers to ensure that the business model is correct with respect to the stakeholder's expectations. One way of achieving this goal is to provide the modelling language with an executable semantics. In this manner, any business model can be executed on sample input data, and its dynamic behaviour observed. The observation of the dynamic behaviour of the model may be considered as a simulation of the model based on the sample input data. By performing several simulations of the model, the modeller, in cooperation with the stakeholder, can judge whether the business model is correct. This thesis provides an executable semantics for Timed-CaaFWrk that, used in combination with the model transformation that defines the semantic mapping element of the language definition, allows DT4BP models to be validated by simulation. In this manner, the dynamic behaviour of a particular DT4BP model for a given sample input data can be observed by transforming it into a Timed-CaaFWrk model, which is then run thanks to the given executable semantics

Analysis of static response of RC beams with NSM CFRP/GFRP rods

In this paper experimental results of investigation on reinforced concrete (RC) beams strengthened with the near surface method (NSM) are analyzed considering the response under bending tests on two beams. One of the RC beams was damaged by bending until the yield of reinforcement and successively strengthened with carbon fiber polymer (CFRP) rod, while the second beam was strengthened with glass-FRP rod. Both the beams have been subjected to bending tests until failure. Experimental diagrams and discussion on static response are presented in the paper. It also places a particular emphasis on the non-linear response of RC sections strengthened with CFRP and GFRP rods under bending moment beyond the first elastic behavior

Exploring new NSM reinforcements for the flexural strengthening of RC beams: experimental and numerical research

Carbon-fiber-reinforced-polymer (CFRP) composite materials applied according to near-surface-mounted (NSM) technique constitute an effective technique for the flexural and shear strengthening of reinforced-concrete (RC) structures. However, the NSM CFRP reinforcement ratio is limited by the thickness of concrete cover of the longitudinal tensile steel bars, and the minimum distance between consecutive CFRPs, below which premature fracture of surrounding concrete occurs due to group effect. Hence, the current study aims to experimentally and numerically evaluate the strengthening potentialities of a novel NSM system (with high CFRP ratio capability) for the flexural strengthening of RC beams. This new system combines externally-bonded-reinforcement (EBR) and NSM techniques in the same application using T-shaped CFRP profiles. The obtained experimental results of the RC beams strengthened with CFRP profiles are presented and discussed with the aim of evaluating the influence of CFRP profile reinforcement ratio on the strengthening efficiency of this technique. A developed 3D finite-element (FE) approach is used to simulate the experimental tests. After demonstrating its good predictive performance, a series of parametric studies is performed to assess the influence of the main material properties, and ratio of bond area to cross sectional area of the CFRP profiles on the efficiency of the proposed system.The first and the last authors acknowledge the support provided by Cutinov QREN project n. 38780 supported by ADI, co-financed by the European Regional Development Fund (FEDER) through the Operational Program COMPETE. The second and the third authors would like to acknowledge the support provided by Mostostal Warszawa S.A. for providing the CFRP T-shaped profiles and for co-funding the research progra

Brewer-Nash Scrutinised: Mechanised Checking of Policies featuring Write Revocation

This paper revisits the Brewer-Nash security policy model inspired by ethical Chinese Wall policies. We draw attention to the fact that write access can be revoked in the Brewer-Nash model. The semantics of write access were underspecified originally, leading to multiple interpretations for which we provide a modern operational semantics. We go on to modernise the analysis of information flow in the Brewer-Nash model, by adopting a more precise definition adapted from Kessler. For our modernised reformulation, we provide full mechanised coverage for all theorems proposed by Brewer & Nash. Most theorems are established automatically using the tool {log} with the exception of a theorem regarding information flow, which combines a lemma in {log} with a theorem mechanised in Coq. Having covered all theorems originally posed by Brewer-Nash, achieving modern precision and mechanisation, we propose this work as a step towards a methodology for automated checking of more complex security policy models

RC beams damaged by cracking and strengthened with NSM CFRP/GFRP rods

The near surface mounted (NSM) method of inserting fiber reinforced polymer (FRP) elements (rods or lamina) into notches has been shown to be a good way for restoring reinforced concrete (RC) elements. The knowledge about the use of Glass-FRP rod following the NSM to reinforce RC beams is limited. This paper deals with the analysis of static and dynamic behaviour of RC beams with and without strengthening. The response of RC beams was assessed at different concrete’s damage level by non-destructive vibration tests. First, a couple of beams have been analysed: one RC beam subjected to bending and under vibration tests; another one beam, damaged by bending and strengthened with NSM Carbon-FRP rods tested again under vibration. Further, one RC beam damage was analysed under bending and vibration tests without strengthening; successively, the beam model with NSM GFRP rod has been tested following the same loading path. Below experimental results are shown and commented; in particular, changes in frequency values are related to the evolution of damage level affected RC beams with NSM CFRP and GFRP rods

Energy Performance Analysis of Advanced Transactional Models

12. Responsible consumption and productio