Determining the Positive Definiteness Margin of Interval Matrices

A method for determining the positive definiteness margin of interval matrices is suggested. It is based on the use of outer interval bounds on the solution set of an interval eigenvalue problem. Three algorithms of the method are developed. It is shown that their numerical complexity is polynomial. Numerical examples illustrating the applicability of the method suggested are provided.     

Impact of a satellite-derived leaf area index monthly climatology in a global numerical weather prediction model

The leaf area index (LAI), defined as the one-sided green leaf area per unit ground area, is used in many numerical weather prediction (NWP) models as an indicator of the vegetation development state, which is of paramount importance to characterize land evaporation, photosynthesis, and carbon-uptake processes. LAI is often simply represented by lookup tables, dependent on the vegetation type and seasons. However, global LAI datasets derived from remote sensing observations have more recently become available. These products are based on sensors such as the Advanced Very High Resolution Radiometer (AVHRR) or the Moderate Resolution Imaging Spectroradiometer (MODIS), onboard polar orbiting satellites that can cover the entire globe within typically 3 days and with a spatial resolution of the order of 1 km.

We examine the meteorological impact of satellite-derived LAI products on near-surface air temperature and humidity, which comes both from the stomatal transpiration of leaves and from the intercepted water on the surface of leaves, re-evaporating into the atmosphere.

Two distinct monthly LAI climatology datasets derived respectively from AVHRR and MODIS sensors are tested. A set of forecasts and data assimilation experiments with the integrated forecasting system of the European Centre for Medium-range Weather Forecasts is performed with the monthly LAI climatology datasets as opposed to a vegetation-dependent constant LAI. The monthly LAI is shown to improve the forecasts of near-surface (screen-level) air temperature and relative humidity through its effect on evapotranspiration, with the largest impact obtained over needleleaf forests, crops, and grassland. At longer time-scales, the introduction of the monthly LAI is shown to have a positive impact on the model climate particularly during the boreal spring, where the LAI climatology has a large seasonal cycle.     

Solutions to a class of non-standard non-linear H infinity control problems

This paper presents new solutions to certain non-standard non-linear H infinity control problems. We consider non-linear affine plants whose measurement output is of dimension larger than the dimension of the external input. This problem is, under proper assumptions, transformed to the problem of stabilization by means of output injection and solution of a Hamilton-Jacobi partial differential inequality arising in singular H infinity state-feedback control. General sufficient solvability conditions are given. Explicit solutions are available in the local and semilocal cases. The former concerns a certain neighbourhood of the origin in the closed loop state-space, whereas the latter assumes that the trajectories are restricted to a neighbourhood of an invariant manifold. The issue of the controller order is addressed and a reducedorder controller is obtained in the local case. A new generalization of the chain-scattering formalism provides a very useful framework for solving this problem.     

A modern 3-D view of an “old” pearlite colony

This paper describes the three-dimensional (3-D) microstructure of a pearlite colony in a carburized electrolytic iron. The original data was obtained by serial sectioning methods around 1960, and is revisited with modern 3-D visualizations. After a brief historical introduction, the structure of the pearlite colony is discussed, using surface renderings and blue-red stereoscopic images.     

Resistance pattern of 2816 isolates isolated from 17631 blood cultures and etiology of bacteremia and fungemia in a single cancer institution

A phase III, open label randomized study was conducted in 50 patients comparing halothane and sevoflurane for paediatric day case surgery. A graded inhalational induction resulted in only slightly more rapid induction with sevoflurane (3.34 +/- 0.92 versus 3.85 +/- 1.02 minutes; P > 0.05). In children receiving sevoflurane, systolic blood pressure decreased to a lesser extent during induction (143 +/- 19.2 versus 26.9 +/- 10.9 percent decrease from resting values; P < 0.01) and heart rate was maintained. Respiratory events (coughing, breath-holding, bronchospasm, laryngospasm) were more common during induction with halothane, and excitement more common in children receiving sevoflurane. Emergence times were significantly more rapid in children who had received sevoflurane (21.4 +/- 10.9 versus 33.1 +/- 13.7 minutes; P < 0.01). Objective pain/discomfort scores were higher in patients receiving sevoflurane at 10, 20, 30 and 40 minutes after arrival in the recovery room, and the incidence of excitement during emergence was higher in this group. It is concluded that sevoflurane is well tolerated for inhalational induction and has an improved cardiovascular profile compared to halothane. Emergence was significantly more rapid following sevoflurane.     

The Influence of Repetition and Famousness on the Intracranially Recorded Temporobasal N200.

It is still a matter of debate at which time point faces are recognized as familiar, with some studies claiming a relatively early face recognition and others later effects of familiarity. The authors report on effects of famousness of depicted persons and stimulus repetition on intracranially recorded event-related potentials. Famousness resulted in an increased latency of the N200 component, as well as in an increased amplitude of a later long-lasting potential (N700). In contrast, repetition led to an increased amplitude of the N200 but no increase of its latency. They suppose that the recognition of faces becomes observable within the N200 latency range and that the increased N200 latency reflects a feature processing additional to the holistic face processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)