Live modeling in the context of state machine models and code generation

Software and Systems Modeling - Live modeling has been recognized as an important technique to edit behavioral models while being executed and helps in better understanding the impact of a design...     

Advanced and efficient execution trace management for executable domain-specific modeling languages

Executable Domain-Specific Modeling Languages (xDSMLs) enable the application of early dynamic verification and validation (V&V) techniques for behavioral models. At the core of such techniques, execution traces are used to represent the evolution of models during their execution. In order to construct execution traces for any xDSML, generic trace metamodels can be used. Yet, regarding trace manipulations, generic trace metamodels lack efficiency in time because of their sequential structure, efficiency in memory because they capture superfluous data, and usability because of their conceptual gap with the considered xDSML. Our contribution is a novel generative approach that defines a multidimensional and domain-specific trace metamodel enabling the construction and manipulation of execution traces for models conforming to a given xDSML. Efficiency in time is improved by providing a variety of navigation paths within traces, while usability and memory are improved by narrowing the scope of trace metamodels to fit the considered xDSML. We evaluated our approach by generating a trace metamodel for fUML and using it for semantic differencing, which is an important V&V technique in the realm of model evolution. Results show a significant performance improvement and simplification of the semantic differencing rules as compared to the usage of a generic trace metamodel.

     

Large language models as an “operating” system for software and systems modeling

Software and Systems Modeling -     

Late outcome of 304 consecutive patients with multiple gland enlargement in primary hyperparathyroidism treated by conservative surgery

The aim of this study was to assess the late outcome of patients with primary hyperparathyroidism and multiple gland enlargement (MGE) treated by conservative surgery. MGE in primary hyperparathyroidism is the presence of two or more enlarged glands weighing more than 50 mg. Conservative surgery consists in resecting the grossly enlarged glands without biopsying the normal glands. Some authors have suggested that this approach overlooks minute hyperplasia, leading to late recurrences of hyperparathyroidism; conversely, it may result in the unnecessary resection of grossly enlarged, but not hyperfunctioning, glands. Altogether 1231 patients were operated on for primary hyperparathyroidism between 1966 and 1995. Of these patients, 304 (24.9%) had MGE, including 42 cases of multiple endocrine neoplasia (MEN), 12 familial cases, and 250 seemingly sporadic cases. Two, three, or four glands (or more) were involved in 61.8%, 21.4%, and 16.4% of cases, respectively. During the early postoperative period one patient died and ten were reoperated for persistent hypercalcemia. The pathologic diagnoses were double adenomas (13.5%), hyperplasia (35.8%), association of the two (39.8%), and a normal second gland (10.8%) on light microscopy findings. None of the 30 deaths that occurred during follow-up was related to hyperparathyroidism. Altogether 190 patients (79%) were available for follow-up (average 89.3 months): 90% were normocalcemic, 4.7% hypocalcemic, and 5.2% hypercalcemic. A late iPTH assay was done in 147. PTH was appropriate to the serum calcium level in 84.3% and appropriate to normal calcemia in 91.6% of 132 cases. Conservative surgery is thus an acceptable treatment for MGE in patients with hyperparathyroidism. Few late recurrences occur, for which there are no individual predictive criteria.     

Erythema dyschromicum perstans: report of a new case and critical review of the literature

Erythema dyschromicum perstans (EDP), described by Convit et al. in 1961, is a rare dermatosis. Its relationship with ashy dermatosis (AD), described by Ramirez in 1957, is still a matter of debate. We report a typical case of EDP. The patient, of North African origin, had a dyschromic (hypo- and hyperpigmented) eruption on the chest and limbs for 2 years. The lesions were occasionally surrounded by a papular border which spread slowly and centrifugally. Histological examination showed a lichenoid infiltrate. A carcinoma of the lung was simultaneously discovered. No treatment was given, EDP is infrequent and often considered identical to ashy dermatosis in the literature. However, the clinical aspects of the two diseases differ. The main features of these two diseases are reviewed and compared on the basis of a literature review. We conclude that EDP and AD are distinct clinical entities.     

Bridging the chasm between MDE and the world of compilation

Modeling and transforming have always been the cornerstones of software system development, albeit often investigated by different research communities. Modeling addresses how information is represented and processed, while transformation cares about what the results of processing this information are. To address the growing complexity of software systems, model-driven engineering (MDE) leverages domain-specific languages to define abstract models of systems and automated methods to process them. Meanwhile, compiler technology mostly concentrates on advanced techniques and tools for program transformation. For this, it has developed complex analyses and transformations (from lexical and syntactic to semantic analyses, down to platform-specific optimizations). These two communities appear today quite complementary and are starting to meet again in the software language engineering (SLE) field. SLE addresses all the stages of a software language lifecycle, from its definition to its tooling. In this article, we show how SLE can lean on the expertise of both MDE and compiler research communities and how each community can bring its solutions to the other one. We then draw a picture of the current state of SLE and of the challenges it has still to face.     

Interface reactivity study between La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) cathode material and metallic interconnect for fuel cell

Interface reactivity between La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ (LSCF) cathode material and metallic interconnect (Crofer22APU) was investigated in laboratory air at 700 °C. Due to the interconnect geometry, two interfaces have been analysed: (i) interconnect rib/cathode interface (physically in contact); (ii) the interface under the channel of interconnect. In both cases, formation of a parasite phase was observed after various ageing treatments (20 h, 100 h and 200 h). However, the growth of the determined SrCrO₄ parasite phase depends on interface type and on ageing time. Two different mechanisms have been established in function of interface type: (i) SrCrO₄ phase was formed after solid state diffusion of Cr from metallic interconnect to the cathode; (ii) gas phase reaction induced formation of SrCrO₄ under the channel of interconnect. Finally, the influence of a chemical etching on cathode/interconnect reactivity was evaluated.