Industrial hardware and software verification with ACL2.

The ACL2 theorem prover has seen sustained industrial use since the mid-1990s. Companies that have used ACL2 regularly include AMD, Centaur Technology, IBM, Intel, Kestrel Institute, Motorola/Freescale, Oracle and Rockwell Collins. This paper introduces ACL2 and focuses on how and why ACL2 is used in industry. ACL2 is well-suited to its industrial application to numerous software and hardware systems, because it is an integrated programming/proof environment supporting a subset of the ANSI standard Common Lisp programming language. As a programming language ACL2 permits the coding of efficient and robust programs; as a prover ACL2 can be fully automatic but provides many features permitting domain-specific human-supplied guidance at various levels of abstraction. ACL2 specifications and models often serve as efficient execution engines for the modelled artefacts while permitting formal analysis and proof of properties. Crucially, ACL2 also provides support for the development and verification of other formal analysis tools. However, ACL2 did not find its way into industrial use merely because of its technical features. The core ACL2 user/development community has a shared vision of making mechanized verification routine when appropriate and has been committed to this vision for the quarter century since the Computational Logic, Inc., Verified Stack. The community has focused on demonstrating the viability of the tool by taking on industrial projects (often at the expense of not being able to publish much).This article is part of the themed issue 'Verified trustworthy software systems'.

Meat quality attributes of Agile Wallabies.

Meat quality traits of Agile Wallaby (Macropus agilis) M. longissimus (loin) and M. semimembranosus (topside) were investigated. Both muscles exhibited a relatively high pH (>5.7) and dark colour (L*-, a*-, and b*-values). Aging the loins from 2 to 21days p.m. had a significant effect on shear force. However, the results regarding shear force, myofibrillar fragmentation index (MFI) and degradation of desmin and troponin-T suggested that the aging response largely occurred within 2days p.m. Suspension of carcasses from one leg resulted in a side effect on shear force of the loin at 2 and 7days p.m., but not on sarcomere length or MFI. Topsides from the free hanging leg exhibited lower shear force values (33 vs 42N) and greater sarcomere lengths (2.51 vs 1.84µM). Tenderness, juiciness, flavour and overall liking were higher for loins than topsides. Sensory scores for the loin and topside were slightly lower and similar, respectively, to those reported for lamb.

IStar: a raster representation for scalable image and volume data.

Topology has been an important tool for analyzing scalar data and flow fields in visualization. In this work, we analyze the topology of multivariate image and volume data sets with discontinuities in order to create an efficient, raster-based representation we call IStar. Specifically, the topology information is used to create a dual structure that contains nodes and connectivity information for every segmentable region in the original data set. This graph structure, along with a sampled representation of the segmented data set, is embedded into a standard raster image which can then be substantially downsampled and compressed. During rendering, the raster image is upsampled and the dual graph is used to reconstruct the original function. Unlike traditional raster approaches, our representation can preserve sharp discontinuities at any level of magnification, much like scalable vector graphics. However, because our representation is raster-based, it is well suited to the real-time rendering pipeline. We demonstrate this by reconstructing our data sets on graphics hardware at real-time rates.