Verification and Validation of Sensor Networks

Sensor networks play an increasingly important role in critical systems infrastructure and should be correct, reliable and robust. In order to achieve these performance goals, it is necessary to verify the correctness of system software and to validate the more broadly defined world and system models. This includes: * Physical Phenomena (PDE models, statistical models, etc.), * Signals (Equations of state, physical properties, etc.), * Sensors (Physics models, noise models, etc.), * Hardware (Failure models, power consumption models, etc.), * RF (Antenna models, bandwidth, delay, propagation, etc.), * Embedded Code (Correctness, complexity, context), * Distributed Algorithms (Correctness, concurrency models, etc.), * Overall Sensor Network and Environment Models (Percolation theory, wave theory, information theory, simulation, etc.). We outline some of the V & V issues involved in the various aspects of sensor networks as well as possible approaches to their development and application both in simulation and in operational deployed systems

Hartree-Fock symmetry breaking around conical intersections

We study the behavior of Hartree-Fock (HF) solutions in the vicinity of conical intersections. These are here understood as regions of a molecular potential energy surface characterized by degenerate or nearly-degenerate eigenfunctions with identical quantum numbers (point group, spin, and electron number). Accidental degeneracies between states with different quantum numbers are known to induce symmetry breaking in HF. The most common closed-shell restricted HF instability is related to singlet-triplet spin degeneracies that lead to collinear unrestricted HF (UHF) solutions. Adding geometric frustration to the mix usually results in noncollinear generalized HF (GHF) solutions, identified by orbitals that are linear combinations of up and down spins. Near conical intersections, we observe the appearance of coplanar GHF solutions that break all symmetries, including complex conjugation and time-reversal, which do not carry good quantum numbers. We discuss several prototypical examples taken from the conical intersection literature. Additionally, we utilize a recently introduced a magnetization diagnostic to characterize these solutions, as well as a solution of a Jahn-Teller active geometry of H$_8^{+2}$.Comment: accepted to JCP December 2017, published online January 201

Simulating accidental fires and explosions

Journal ArticleThe Center for the Simulation of Accidental Fires and Explosions at the University of Utah focuses on providing state-of-the-art, science-based tools for the numerical simulation of accidental fires and explosions, especially in the context of handling and storing highly flammable materials

Leadership protocol for S-Nets

technical reportSmart Sensor Networks are collections of non-mobile devices (S-elements) which can compute, communicate and sense the environment; they must be able to create local groups of devices (S-cliques). We propose here a protocol to solve the leadership problems for S-Nets. We sketch the correctness of this protocol in terms of an asynchronous network model, and give an example implementation

Logical behaviors

technical reportIn this paper we describe an approach to high-level multisensor integration in t h e context of an autonomous mobile robot. Previous papers have described the development of t h e INRIA mobile robot subsystems: 1. sensor and actuator systems 2. distance and range analysis 3. feature extraction and segmentation 4. motion detection 5. uncertainty management, and 6. 3 -D environment descriptions. We describe here an approach to: ? the semantic analysis of the 3-D environment descriptions

Explicit and persistent knowledge in engineering drawing analysis

technical reportDomain knowledge permeates all aspects of the engineering drawing analysis process, including understanding the physical processes operating on the medium (i.e., paper), the image analysis techniques, and the interpretation semantics of the structural layout and contents of the drawing. Additionally, an understanding of the broader reverse engineering context, within which the drawing analysis takes place, should be exploited. Thus as part of a wider project on the reverse engineering of legacy systems, we have developed an agent-based engineering analysis system called NDAS (nonDeterministic Agent System). In this paper, we discuss the nature of such a system and how knowledge can be made explicit (both for agents and humans) and how performance models can be de?ned, calibrated, monitored, and improved over time through the use of persistent knowledge. A framework is proposed that allows computational agents to: (1) explore the threshold space for an optimal analysis of the drawing, (2) control information gain through agent invocation, (3) incorporate and communicate knowledge, and (4) inform the software engineering and system development with deep knowledge of the relationships between modules and their parameters (at least in a statistical sense)

Reliable and robust molecular sexing of the hen harrier (Circus cyaneus) using PCR-RFLP of the CHD1 gene

The hen harrier (Circus cyaneus) is a bird of prey that is persecuted in the United Kingdom, and there is a need for a DNA-based individual identification and sexing system for the use in forensic investigations. This study reports a new set of PCR primers for the chromo-helicase-DNA-binding protein 1 gene, which allows sexing using PCR-RFLP. Instead of exonic primers that amplify across a large intron, this set consists of a primer within the intron, enabling reduction in amplicon sizes from 356 to 212 bp and 565 to 219 bp in W and Z chromosomes. DNA degradation and dilution experiments demonstrate that this set is significantly more robust than one that amplifies across the intron, and sequencing of the intronic primer-binding region across several individuals shows that it is highly conserved. While our objective is to incorporate this primer set into an STR-based individualization kit, it may in the meantime prove useful in forensic or conservation studies

Determination of complex absorbing potentials from the electron self-energy

The electronic conductance of a molecule making contact to electrodes is determined by the coupling of discrete molecular states to the continuum electrode density of states. Interactions between bound states and continua can be modeled exactly by using the (energy-dependent) self-energy, or approximately by using a complex potential. We discuss the relation between the two approaches and give a prescription for using the self-energy to construct an energy-independent, non-local, complex potential. We apply our scheme to studying single-electron transmission in an atomic chain, obtaining excellent agreement with the exact result. Our approach allows us to treat electron-reservoir couplings independent of single electron energies, allowing for the definition of a one-body operator suitable for inclusion into correlated electron transport calculations.Comment: 11 pages, 8 figures; to be published in the J. Chem. Phy