Low-power multi-chip module and board-level links for data transfer

Advanced device technologies such as Vertical Cavity Surface-Emitting Lasers (VCSELs) and diffractive micro lenses can be obtained with novel packaging techniques to allow low-power interconnection of parallel optical signals. These interconnections can be realized directly on circuit boards, in a multi-chip module format, or in packages that emulate electrical connectors. For applications such as stacking of Multi-Chip Module (MCM) layers, the links may be realized in bi-directional form using integrated diffractive microlenses. In the stacked MCM design, consumed electrical power is minimized by use of a relatively high laser output from high efficiency VCSELs, and a receiver design that is optimized for low power, at the expense of dynamic range. Within certain constraints, the design may be extended to other forms such as board-level interconnects

Automatic Creation of Environment Models via Training

Abstract. Model checking suffers not only from the state-space explosion problem, but also from the environment modeling problem: how can one create an accurate enough model of the environment to enable precise yet efficient model checking? We present a novel approach to the automatic creation of environment models via training. The idea of training is to take several programs that use a common API and apply model checking to create abstractions of the API procedures. These abstractions then are reused on subsequent verification runs to model-check different programs (which utilize the same API). This approach has been realized in SLAM, a software model checker for C programs, and applied to the domain of Windows device drivers that utilize the Windows Driver Model API (a set of entry points into the Windows kernel). We show how the boolean abstractions of the kernel routines accessed from a device driver are extracted and merged into a boolean library that can be reused by subsequent model checking runs on new drivers. We show that the merged abstraction is a conservative extension of the boolean abstractions created by training.

Translating software designs for model checking

This paper presents a systematic consideration of the major issues involved in translation of executable design level software specification languages to directly model-checkable formal languages. These issues are considered under the framework of integrated model/property translation and include: (1) translator architecture; (2) semantics translation from a software language to a formal language; (3) property specification and translation; (4) transformations for state space reduction; (5) translator validation and evolution. Solutions to these issues are defined, described, and illustrated in the context of translating xUML, an executable design level software specification language, to S/R, the input formal language of the COSPAN model checker

Susceptibility of Italian agile frog populations to an emerging strain of Ranavirus parallels population genetic diversity.

Western populations of the Italian agile frog (Rana latastei) experience widespread genetic depletion. Based on population genetic theory, molecular models of immunity and previous empirical studies, population genetic depletion predicts increased susceptibility of populations to emergent pathogens. We experimentally compared susceptibility of R. latastei populations upon exposure to an emerging strain of Ranavirus, frog virus 3 (FV3), using six populations spanning the geographical range and range of population genetic diversity found in nature. Our findings confirm this prediction, suggesting that the loss of genetic diversity accompanying range expansion and population isolation is coincident with increased mortality risk from an emergent pathogen. Loss of heterozygosity and escape from selection imposed by immunologically cross-reactive pathogens may potentially generate range-wide variation in disease resistance