Case study: Class diagram restructuring

This case study is an update-in-place refactoring transformation on UML class diagrams. Its aim is to remove clones of attributes from a class diagram, and to identify new classes which abstract groups of classes that share common data features. It is used as one of a general collection of transformations (such as the removal of redundant inheritance, or multiple inheritance) which aim to improve the quality of a specification or design level class diagram. The transformation is a typical example of a model refactoring, and illustrates the issues involved in such transformations.Comment: In Proceedings TTC 2013, arXiv:1311.753

Solving the Petri-Nets to Statecharts Transformation Case with UML-RSDS

This paper provides a solution to the Petri-Nets to statecharts case using UML-RSDS. We show how a highly declarative solution which is confluent and invertible can be given using this approach.Comment: In Proceedings TTC 2013, arXiv:1311.753

Language-independent model transformation verification

One hinderance to model transformation verification is the large number of different MT languages which exist, resulting in a large number of different language-specific analysis tools. As an alternative, we define a single analysis process which can, in principle, analyse speci- fications in several different transformation languages, by making use of a common intermediate representation to express the semantics of trans- formations in any of these languages. Some analyses can be performed directly on the intermediate representation, and further semantic models in specific verification formalisms can be derived from it. We illustrate the approach by applying it to ATL

Saying Hello World with UML-RSDS - A Solution to the 2011 Instructive Case

In this paper we apply the UML-RSDS notation and tools to the "Hello World" case studies and explain the underlying development process for this model transformation approach.Comment: In Proceedings TTC 2011, arXiv:1111.440

Solving the TTC 2011 Model Migration Case with UML-RSDS

In this paper we apply the UML-RSDS notation and tools to the GMF model migration case study and explain how to use the UML-RSDS tools.Comment: In Proceedings TTC 2011, arXiv:1111.440

Verification of model transformations

Model transformations are a central element of model-driven development (MDD) approaches such as the model-driven architecture (MDA). The correctness of model transformations is critical to their effective use in practical software development, since users must be able to rely upon the transformations correctly preserving the semantics of models. In this paper we define a formal semantics for model transformations, and provide techniques for proving the termination, confluence and correctness of model transformations

Automating reconfiguration chain generation for SRL-based run-time reconfiguration

Run-time reconfiguration (RTR) of FPGAs is mainly done using the configuration interface. However, for a certain group of designs, RTR using the shift register functionality of the LUTs is a much faster alternative than conventional RTR using the ICAP. This method requires the creation of reconfiguration chains connecting the run-time reconfigurable LUTs (SRL). In this paper, we develop and evaluate a method to generate these reconfiguration chains in an automated way so that their influence on the RTR design is minimised and the reconfiguration time is optimised. We do this by solving a constrained multiple travelling salesman problem (mTSP) based on the placement information of the run-time reconfigurable LUTs. An algorithm based on simulated annealing was developed to solve this new constrained mTSP. We show that using the proposed method, reconfiguration chains can be added with minimal influence on the clock frequency of the original design

Evaluation of Model Transformation Approaches for Model Refactoring

This paper provides a systematic evaluation framework for comparing model transformation approaches, based upon the ISO/IEC 9126-1 quality characteristics for software systems. We apply this framework to compare five transformation approaches (QVT-R, ATL, Kermeta, UMLRSDS and GrGen.NET) on a complex model refactoring case study: the amalgamation of apparent attribute clones in a class diagram. The case study highlights the problems with the specification and design of the refactoring category of model transformations, and provides a challenging example by which model transformation languages and approaches can be compared. We take into account a wide range of evaluation criteria aspects such as correctness, efficiency, flexibility, interoperability, reusability and robustness, which have not been comprehensively covered by other comparative surveys of transformation approaches. The results show clear distinctions between the capabilities and suitabilities of different approaches to address the refactoring form of transformation problem

Biosynthesis and Characterization of Silver Nanoparticles by Aspergillus Species

Currently, researchers turn to natural processes such as using biological microorganisms in order to develop reliable and ecofriendly methods for the synthesis of metallic nanoparticles. In this study, we have investigated extracellular biosynthesis of silver nanoparticles using four Aspergillus species including A. fumigatus, A. clavatus, A. niger, and A. flavus. We have also analyzed nitrate reductase activity in the studied species in order to determine the probable role of this enzyme in the biosynthesis of silver nanoparticles. The formation of silver nanoparticles in the cell filtrates was confirmed by the passage of laser light, change in the color of cell filtrates, absorption peak at 430 nm in UV-Vis spectra, and atomic force microscopy (AFM). There was a logical relationship between the efficiencies of studied Aspergillus species in the production of silver nanoparticles and their nitrate reductase activity. A. fumigatus as the most efficient species showed the highest nitrate reductase activity among the studied species while A. flavus exhibited the lowest capacity in the biosynthesis of silver nanoparticles which was in accord with its low nitrate reductase activity. The present study showed that Aspergillus species had potential for the biosynthesis of silver nanoparticles depending on their nitrate reductase activity