HeteroGenius: A Framework for Hybrid Analysis of Heterogeneous Software Specifications

Nowadays, software artifacts are ubiquitous in our lives being an essential part of home appliances, cars, cell phones, and even in more critical activities like aeronautics and health sciences. In this context software failures may produce enormous losses, either economical or, in the worst case, in human lives. Software analysis is an area in software engineering concerned with the application of diverse techniques in order to prove the absence of errors in software pieces. In many cases different analysis techniques are applied by following specific methodological combinations that ensure better results. These interactions between tools are usually carried out at the user level and it is not supported by the tools. In this work we present HeteroGenius, a framework conceived to develop tools that allow users to perform hybrid analysis of heterogeneous software specifications. HeteroGenius was designed prioritising the possibility of adding new specification languages and analysis tools and enabling a synergic relation of the techniques under a graphical interface satisfying several well-known usability enhancement criteria. As a case-study we implemented the functionality of Dynamite on top of HeteroGenius.Comment: In Proceedings LAFM 2013, arXiv:1401.056

Modeling and Experimental Study of Lithium-Ion Battery Thermal Behavior

While the popularity of lithium-ion batteries (LIBs) has increased significantly in recent years, safety concerns due to the high thermal instability of LIBs limit their use in applications with zero tolerance for failure. A safety issue of particular interest is a scenario called thermal runaway in which several exothermic side-reactions occur at elevated temperature ranges and release heat, which can then trigger the next reaction. This matter worsens when multiple cells are installed in close proximity to each other as the released heat from an abused cell can activate the chain of reactions in a neighboring cell, causing an entire module to heat rapidly and vent or ignite. This body of work aims to study LIB thermal behavior using both modeling and experiments to determine design practices that improve the safety of LIB modules. Based on the results of single cell abuse testing, a numerical model of the side-reactions that occur during thermal runaway was developed. The results showed that cell form factor and ambient conditions influence abuse behavior significantly. These abuse tests were extended to multi-cell modules to determine the effect of cell spacing, electrical configuration, and protection materials on the propagation of thermal runaway from an abused cell to a surrounding one. Lastly, an electrochemically coupled thermal model of battery thermal management systems of various configurations was created. An optimum thermal management design was found that utilized both active and passive methods of cooling to keep cell temperatures and thermal gradients within safe limits. The work described herein is expected to provide insight into safe battery design practices

Focal Dermal Hypoplasia with Uterus Bicornis and Renal Ectopia: Case Report and Review of the Literature

Focal dermal hypoplasia (FDH) is a rare inherited genodermatosis with an X-linked dominant trait. FDH is associated with skin defects and other abnormalities of bone, nails, hair, limbs, teeth and eyes. We present the case of a 26-year-old female in the 27th pregnancy week and a previous history of miscarriage. After careful physical examination and dermal biopsy, histopathology revealed that the patient was a carrier of FDH. This is the first report in the literature describing that FDH is associated with uterus bicornis and renal ectopia. Our association could be attributable to early embryonic abnormalities related with FDH because both the uterus bicornis and the renal ectopia originate around the 3th-6th week of embryonic development. We are unable to confirm that the miscarriages were caused by inherited FDH or that uterus bicornis was the cause. We conducted a literature review using the following terms: FDH, Goltz syndrome, uterus bicornis, and renal ectopia

On the construction of explosive relation algebras

Fork algebras are an extension of relation algebras obtained by extending the set of logical symbols with a binary operator called fork. This class of algebras was introduced by Haeberer and Veloso in the early 90's aiming at enriching relation algebra, an already successful language for program specification, with the capability of expressing some form of parallel computation. The further study of this class of algebras led to many meaningful results linked to interesting properties of relation algebras such as representability and finite axiomatizability, among others. Also in the 90's, Veloso introduced a subclass of relation algebras that are expansible to fork algebras, admitting a large number of non-isomorphic expansions, referred to as explosive relation algebras. In this work we discuss some general techniques for constructing algebras of this type