We formulate the sensor network localization problem as finding the global minimizer of a quartic polynomial. Then sum of squares (SOS) relaxations can be applied to solve it. However, the general SOS relaxations are too expensive to implement for large problems. Exploiting the special features of this polynomial, we propose a new structured SOS relaxation, and discuss its various properties. W...

The Ras-specific nucleotide exchange factor Son of sevenless (Sos) is inactive without Ras bound to a distal allosteric site. In contrast, the catalytic domain of Ras guanine nucleotide releasing factor 1 (RasGRF1) is active intrinsically. By substituting residues from RasGRF1 into Sos, we have generated mutants of Sos with basal activity, partially relieved of their dependence on allosteric ac...

The SOS system and SOS mutagenesis are frequently studied, or exploited to obtain an increase in mutagenicity of bacteria. Here a short survey is made of the phenomenon of SOS response with special attention to latest and less discussed data, especially the induction of the SOS system in response to cell starvation or mutation of certain genes and the role of inducible DNA polymerases.

Systems of Systems (SoS) are a current focus of many organizations interested in integrating assets and utilizing new technology to create multi-component systems that deliver value over time. The dynamic composition of SoS along with the managerial independence of their component systems necessitates systems engineering considerations and methods beyond those of traditional systems engineering...

The ongoing changes in vegetation spring phenology in temperate/cold regions are widely attributed to temperature. However, in arid/semiarid ecosystems, the correlation between spring temperature and phenology is much less clear. We test the hypothesis that precipitation plays an important role in the temperature dependency of phenology in arid/semiarid regions. We therefore investigated the in...

Introduction The aim of the study was to establish reference data for tibia and radius bone ultrasonic speed of sound (SOS) measurement in our pediatric population, and to compare the results with original (built-in) reference data. We also investigated the relationship between SOS Z-scores and anthropometric parameters and bone markers. Method SOS was measured in 463 healthy children (1– 16 ye...

Axial speed of sound (SOS) measurements have been successfully applied to noninvasively evaluate tendon load, while preliminary studies showed that this technique also has a potential clinical interest in the follow up of tendon injuries. The ultrasound propagation theory predicts that the SOS is determined by the effective stiffness, mass density and Poisson’s ratio of the propagating medium. ...

Previous papers have described a computational approach to System of Systems (SoS) development using an Agent-Based Model (ABM). This paper describes the Fuzzy Decision Analysis used in the negotiation between the SoS agent and a System agent in the ABM of an Acknowledged SoS development. An Acknowledged SoS has by definition a limited influence on the development of the individual Systems. The...

Several methods exist for extracting plant phenological information from time series of satellite data. However, there have been only a few successful attempts to temporarily match satellite observations (Land Surface Phenology or LSP) with ground based phenological observations (Ground Phenology or GP). The classical pixel to point matching problem along with the temporal and spatial resolutio...