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Article
Publication date: 28 August 2009

Manuel Wimmer

The definition of modeling languages is a key‐prerequisite for model‐driven engineering. In this respect, Domain‐Specific Modeling Languages (DSMLs) defined from scratch…

Abstract

Purpose

The definition of modeling languages is a key‐prerequisite for model‐driven engineering. In this respect, Domain‐Specific Modeling Languages (DSMLs) defined from scratch in terms of metamodels and the extension of Unified Modeling Language (UML) by profiles are the proposed options. For interoperability reasons, however, the need arises to bridge modeling languages originally defined as DSMLs to UML. Therefore, the paper aims to propose a semi‐automatic approach for bridging DSMLs and UML by employing model‐driven techniques.

Design/methodology/approach

The paper discusses problems of the ad hoc integration of DSMLs and UML and from this discussion a systematic and semi‐automatic integration approach consisting of two phases is derived. In the first phase, the correspondences between the modeling concepts of the DSML and UML are defined manually. In the second phase, these correspondences are used for automatically producing UML profiles to represent the domain‐specific modeling concepts in UML and model transformations for transforming DSML models to UML models and vice versa. The paper presents the ideas within a case study for bridging ComputerAssociate's DSML of the AllFusion Gen CASE tool with IBM's Rational Software Modeler for UML.

Findings

The ad hoc definition of UML profiles and model transformations for achieving interoperability is typically a tedious and error‐prone task. By employing a semi‐automatic approach one gains several advantages. First, the integrator only has to deal with the correspondences between the DSML and UML on a conceptual level. Second, all repetitive integration tasks are automated by using model transformations. Third, well‐defined guidelines support the systematic and comprehensible integration.

Research limitations/implications

The paper focuses on the integrating direction DSMLs to UML, but not on how to derive a DSML defined in terms of a metamodel from a UML profile.

Originality/value

Although, DSMLs defined as metamodels and UML profiles are frequently applied in practice, only few attempts have been made to provide interoperability between these two worlds. The contribution of this paper is to integrate the so far competing worlds of DSMLs and UML by proposing a semi‐automatic approach, which allows exchanging models between these two worlds without loss of information.

Details

International Journal of Web Information Systems, vol. 5 no. 3
Type: Research Article
ISSN: 1744-0084

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Article
Publication date: 20 November 2009

Blesson Varghese and Gerard McKee

The purpose of this paper is to address a classic problem – pattern formation identified by researchers in the area of swarm robotic systems – and is also motivated by the…

Abstract

Purpose

The purpose of this paper is to address a classic problem – pattern formation identified by researchers in the area of swarm robotic systems – and is also motivated by the need for mathematical foundations in swarm systems.

Design/methodology/approach

The work is separated out as inspirations, applications, definitions, challenges and classifications of pattern formation in swarm systems based on recent literature. Further, the work proposes a mathematical model for swarm pattern formation and transformation.

Findings

A swarm pattern formation model based on mathematical foundations and macroscopic primitives is proposed. A formal definition for swarm pattern transformation and four special cases of transformation are introduced. Two general methods for transforming patterns are investigated and a comparison of the two methods is presented. The validity of the proposed models, and the feasibility of the methods investigated are confirmed on the Traer Physics and Processing environment.

Originality/value

This paper helps in understanding the limitations of existing research in pattern formation and the lack of mathematical foundations for swarm systems. The mathematical model and transformation methods introduce two key concepts, namely macroscopic primitives and a mathematical model. The exercise of implementing the proposed models on physics simulator is novel.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 2 no. 4
Type: Research Article
ISSN: 1756-378X

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Article
Publication date: 27 March 2020

Łukasz Łach and Dmytro Svyetlichnyy

Some functional properties of engineering materials, i.e. physical, mechanical and thermal ones, depend directly on the microstructure, which is a result of processes…

Abstract

Purpose

Some functional properties of engineering materials, i.e. physical, mechanical and thermal ones, depend directly on the microstructure, which is a result of processes occurring in the material during the forming and thermomechanical processing. The proper microstructure can be obtained in many cases by the phase transformation. This phenomenon is one of the most important processes during hot forming and heat treatment. The purpose of this paper is to develop a new comprehensive hybrid model for modeling diffusion phase transformations. A problem has been divided into several tasks and is carried out on several stages. The purpose of this stage is a development of the structure of a hybrid model, development of an algorithm used in the diffusion module and one-dimensional heat flow and diffusion modeling. Generally, the processes of phase transformations are studied well enough but there are not many tools for their complex simulations. The problems of phase transformation simulation are related to the proper consideration of diffusion, movement of phase boundaries and kinetics of transformation. The proposed new model at the final stage of development will take into account the varying grain growth rate, different shape of growing grains and will allow for proper modeling of heat flow and carbon diffusion during the transformation in many processes, where heating, annealing and cooling can be considered (e.g. homogenizing and normalizing).

Design/methodology/approach

One of the most suitable methods for modeling of microstructure evolution during the phase transformation is cellular automata (CA), while lattice Boltzmann method (LBM) suits for modeling of diffusion and heat flow. Then, the proposed new hybrid model is based on CA and LBM methods and uses high performing parallel computations.

Findings

The first simulation results obtained for one-dimensional modeling confirm the correctness of interaction between LBM and CA in common numerical solution and the possibility of using these methods for modeling of phase transformations. The advantages of the LBM method can be used for the simulation of heat flow and diffusion during the transformation taking into account the results obtained from the simulations. LBM creates completely new possibilities for modeling of phase transformations in combination with CA.

Practical implications

The studies are focused on diffusion phase transformations in solid state in condition of low cooling rate (e.g. transformation of austenite into ferrite and pearlite) and during the heating and annealing (e.g. transformation of the ferrite-pearlite structure into austenite, the alignment of carbon concentration in austenite and growth of austenite grains) in carbon steels within a wide range of carbon content. The paper presents the comprehensive modeling system, which can operate with the technological processes with phase transformation during heating, annealing or cooling.

Originality/value

A brief review of the modeling of phase transformations and a description of the structure of a new CA and LBM hybrid model and its modules are presented in the paper. In the first stage of model implementation, the one-dimensional LBM model of diffusion and heat flow was developed. The examples of simulation results for several variants of modeling with different boundary conditions are shown.

Details

Engineering Computations, vol. 37 no. 8
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 16 April 2018

Daniel de Bortoli, Fauzan Adziman, Eduardo A. de Souza Neto and Francisco M. Andrade Pires

The purpose of this work is to apply a recently proposed constitutive model for mechanically induced martensitic transformations to the prediction of transformation loci…

Abstract

Purpose

The purpose of this work is to apply a recently proposed constitutive model for mechanically induced martensitic transformations to the prediction of transformation loci. Additionally, this study aims to elucidate if a stress-assisted criterion can account for transformations in the so-called strain-induced regime.

Design/methodology/approach

The model is derived by generalising the stress-based criterion of Patel and Cohen (1953), relying on lattice information obtained using the Phenomenological Theory of Martensite Crystallography. Transformation multipliers (cf. plastic multipliers) are introduced, from which the martensite volume fraction evolution ensues. The associated transformation functions provide a variant selection mechanism. Austenite plasticity follows a classical single crystal formulation, to account for transformations in the strain-induced regime. The resulting model is incorporated into a fully implicit RVE-based computational homogenisation finite element code.

Findings

Results show good agreement with experimental data for a meta-stable austenitic stainless steel. In particular, the transformation locus is well reproduced, even in a material with considerable slip plasticity at the martensite onset, corroborating the hypothesis that an energy-based criterion can account for transformations in both stress-assisted and strain-induced regimes.

Originality/value

A recently developed constitutive model for mechanically induced martensitic transformations is further assessed and validated. Its formulation is fundamentally based on a physical metallurgical mechanism and derived in a thermodynamically consistent way, inheriting a consistent mechanical dissipation. This model draws on a reduced number of phenomenological elements and is a step towards the fully predictive modelling of materials that exhibit such phenomena.

Details

Engineering Computations, vol. 35 no. 2
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 7 June 2011

Melissa Cheung and Jan Hidders

This paper aims to present how iterative round‐trip modelling between two different business process modelling tools can be enabled on a conceptual level. Iterative…

Abstract

Purpose

This paper aims to present how iterative round‐trip modelling between two different business process modelling tools can be enabled on a conceptual level. Iterative round‐trip modelling addresses model transformations between high‐level business and executable process models, and how to maintain these transformations in change time. Currently, the development of these process models is supported by different tools. To the authors' best knowledge, no coherent collaborative tool environment exists that supports iterative round‐trip modelling.

Design/methodology/approach

This paper is primarily based on a literature review of state‐of‐the‐art business to IT transformations regarding business process modelling. The architecture of integrated information systems (ARIS) and Cordys tools are used as an example case in this research. ARIS is a business process analysis (BPA) tool suited for analyzing and designing business processes, while the execution and monitoring of these processes is allowed by Cordys, a business process management suite (BPMS). The theory is used for transforming between ARIS event‐driven process chains from the business perspective and business process modelling notation in Cordys from the IT perspective.

Findings

A conceptual framework is proposed to couple a BPA and BPMS tool for round‐trip business process modelling. The framework utilizes concepts from the model‐driven architecture for structurally addressing interoperability and model transformations. Ensuring iterative development with two tools requires traceability of model transformations.

Practical implications

In many organizations, BPA and BPMS tools are used for business process modelling. These are in practice often two different worlds, while they concern around the same business processes. Maintaining multiple versions of the same process models across two tools is a considerable task, as they often are subject to design changes. Interoperability between a BPA and BPMS tool will minimize redundant activities, and reduce business to IT deployment time.

Originality/value

This research provides a theoretical base for coupling a BPA and BPMS tool regarding iterative round‐trip modelling. It provides an overview of the current state‐of‐the‐art literature of business process modelling transformations, and what is necessary for maintaining interoperability between tools. The findings indicate what is expected in tool support for iterative development in business process modelling from analysis and design to execution.

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Article
Publication date: 7 August 2017

Tao Yan, Liang Ma, Shuo Zhao and Enlin Yu

This study aims to focus on numerical simulation investigations of phase transformation during cooling of 55SiMnMo steel, which is commonly applied to improve mechanical…

Abstract

Purpose

This study aims to focus on numerical simulation investigations of phase transformation during cooling of 55SiMnMo steel, which is commonly applied to improve mechanical properties.

Design/methodology/approach

A mathematical model based on the finite element method (FEM) and the phase transformation kinetics model has been proposed to predict microstructure changes during continuous cooling of 55SiMnMo steel. This model can be employed to analyze the variation of austenite, special upper bainite and lump-like composite structure with cooling time at different cooling rates.

Finding

According to the continuous cooling experiments, when the cooling rate is lower than 0.1°C/s, the special upper bainite is the only transformation product which decreases with increasing cooling rate; when the cooling rate is above 0.5°C/s, the transformation products include special upper bainite and lump-like composite structure. Meanwhile, the results of continuous cooling experiment verified the correctness of this finite element model.

Originality/value

This model has a great value for proper controlling of the cooling process which can improve the quality of hollow drill steel and increase the service life of the final product.

Details

World Journal of Engineering, vol. 14 no. 4
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 19 July 2019

Łukasz Łach, Dmytro Svyetlichnyy and Robert Straka

A fundamental principle of materials engineering is that the microstructure of a material controls the properties. The phase transformation is an important phenomenon that…

Abstract

Purpose

A fundamental principle of materials engineering is that the microstructure of a material controls the properties. The phase transformation is an important phenomenon that determines the final microstructure. Recently, many analytical and numerical methods were used for modeling of phase transformation, but some limitations can be seen in relation to the choice of the shape of growing grains, introduction of varying grain growth rate and modeling of diffusion phenomena. There are also only few comprehensive studies that combine the final microstructure with the actual conditions of its formation. Therefore, the objective of the work is a development of a new hybrid model based on lattice Boltzmann method (LBM) and cellular automata (CA) for modeling of the diffusional phase transformations. The model has a modular structure and simulates three basic phenomena: carbon diffusion, heat flow and phase transformation. The purpose of this study is to develop a model of heat flow with consideration of enthalpy of transformation as one of the most important parts of the proposed new hybrid model. This is one of the stages in the development of the complex model, and the obtained results will be used in a combined solution of heat flow and carbon diffusion during the modeling of diffusion phase transformations.

Design/methodology/approach

Different values of overheating/overcooling affect different values in the enthalpy of transformation and thus the rate of transformation. CA and LBM are used in the hybrid model in part related to heat flow. LBM is used for modeling of heat flow, while CA is used for modeling of the microstructure evolution during the phase transformation.

Findings

The use of LBM and CA in one numerical solution creates completely new possibilities for modeling of phase transformations. CA and LBM in comparison with commonly used approaches significantly simplify interface and interaction between different parts of the model, which operates in a common domain. The CA can be used practically for all possible processes that consist of nucleation and grains growth. The advantages of the LBM method can be well used for the simulation of heat flow during the transformation, which is confirmed by numerical results.

Practical implications

The developed heat flow model will be combined with the carbon diffusion model at the next stage of work, and the new complex hybrid model at the final stage will provide new solutions in numerical simulation of phase transformations and will allow comprehensive modeling of the diffusional phase transformations in many processes. Heating, annealing and cooling can be considered.

Originality/value

The paper presents the developed model of heat flow (temperature module), which is one of the main parts of the new hybrid model devoted to modeling of phase transformation. The model takes into account the enthalpy of transformation, and the connection with the model of microstructure evolution was obtained.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 1 January 2005

R. Obiała, B.H.V. Topping, G.M. Seed and D.E.R. Clark

This paper describes how non‐orthogonal geometric models may be transformed into orthogonal polyhedral models. The main purpose of the transformation is to obtain a…

Abstract

Purpose

This paper describes how non‐orthogonal geometric models may be transformed into orthogonal polyhedral models. The main purpose of the transformation is to obtain a geometric model that is easy to describe and further modify without loss of topological information from the original model.

Design/methodology/approach

The transformation method presented in this paper is based on fuzzy logic (FL). The idea of using FL for this type of transformation was first described by Takahashi and Shimizu. This paper describes both philosophy and techniques behind the transformation method as well as its application to some example 2D and 3D models. The problem in this paper is to define a transformation technique that will change a non‐orthogonal model into a similar orthogonal model. The orthogonal model is unknown at the start of the transformation and will only be specified once the transformation is complete. The model has to satisfy certain conditions, i.e. it should be orthogonal.

Findings

The group of non‐orthogonal models that contain triangular faces such as tetrahedra or pyramids cannot be successfully recognized using this method. This algorithm fails to transform these types of problem because to do so requires modification of the structure of the model. It appears that only when the edges are divided into pieces and the sharp angles are smoothed then the method can be successfully applied. Even though the method cannot be applied to all geometric models many successful examples for 2D and 3D transformation are presented. Orthogonal models with the same topology, which make them easier to describe, are obtained.

Originality/value

This transformation makes it possible to apply simple algorithms to orthogonal models enabling the solution of complex problems usually requiring non‐orthogonal models and more complex algorithms.

Details

Engineering Computations, vol. 22 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 27 May 2014

Andreas Eckhardt, Sven Laumer, Christian Maier and Tim Weitzel

There is only scarce research about the transformation of e-HRM in general, and of the e-recruiting function in particular. Further, there is not much known of the…

Abstract

Purpose

There is only scarce research about the transformation of e-HRM in general, and of the e-recruiting function in particular. Further, there is not much known of the transformational implications for the related people, process, and information technology (IT). The paper aims to discuss these issues.

Design/methodology/approach

To analyze the transformation of e-recruiting caused by external influences outside of the organization, the authors report the results of an eight-year case with a media corporation in order to derive and describe five consecutive steps of an e-recruiting transformation model.

Findings

The paper comes up with five stages (transformation of tools, transformation of systems, transformation of workflows, transformation of tasks, and transformation of communication), each influenced by external developments and market tendencies (War for Talent, increasing number of applications, job market switch, globalization of job market, changing communication behavior).

Research limitations/implications

This research contributes to literature by explaining the drivers of an e-HRM transformation and the different stages of this transformation process differentiated by the affected people, processes, and IT. However, it only observes the transformation in one company, hence the transformation of further e-HRM functions in other companies might differ.

Practical implications

The paper highlights both the transformation of e-recruiting and for the related people, processes, and IT, so companies could observe their current status of e-recruiting transformation.

Originality/value

This paper represents the first longitudinal approach observing the transformation of e-recruiting by describing different stages and external influences.

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Article
Publication date: 6 July 2015

Andree-Anne Lemieux, Samir Lamouri, Robert Pellerin and Simon Tamayo

The purpose of this paper is to propose a leagile transformation model for product development that guides manufacturers in the construction of a road map and the…

Abstract

Purpose

The purpose of this paper is to propose a leagile transformation model for product development that guides manufacturers in the construction of a road map and the management of its deployment in line with both lean and agile improvement objectives.

Design/methodology/approach

An intervention qualitative and transformative research approach was adopted in order to develop required knowledge to theorise professional practice made from rigorous observations of facts. The research project took place over a period of two and a half years, in partnership with an international firm that develops and produces a wide range of luxury products.

Findings

The application of the methodology proved that a lean transformation does not have to be generated only by the field needs but it can follow a mixed approach where a top-down transformation management linked with strategic objectives is deployed without compromising implication and needs from people on the field. The right balance can be found between the strategic aspect of transformation and the incremental aspect on the field of lean paradigms.

Research limitations/implications

For complete validation and widespread scientific application, the model should be tested in other sectors and industries.

Practical implications

The application case of the leagile model in several divisions of a luxury organisation proved that the proposed approach can be used as a guide for manufacturer in the construction of an improvement road map and in the management of its deployment. The application cases enabled a number of positive results to be generated and measured on quantitative indicators such as service ratio for new products for which, one of the divisions saw an increase of 30 per cent. The approach created a positive revolution among development team members by its potential in terms of communication, steering, benchmarking and knowledge system.

Originality/value

The model supports the identification and prioritisation of improvement initiatives by focusing on the levers for improvement that meet the needs and objectives of transformation, as well as the organisation’s maturity level.

Details

Business Process Management Journal, vol. 21 no. 4
Type: Research Article
ISSN: 1463-7154

Keywords

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