Fault diagnosis for uncertain networked systems

Fault diagnosis has been at the forefront of technological developments for several decades. Recent advances in many engineering fields have led to the networked interconnection of various systems. The increased complexity of modern systems leads to a larger number of sources of uncertainty which must be taken into consideration and addressed properly in the design of monitoring and fault diagnosis architectures. This chapter reviews a model-based distributed fault diagnosis approach for uncertain nonlinear large-scale networked systems to specifically address: (a) the presence of measurement noise by devising a filtering scheme for dampening the effect of noise; (b) the modeling of uncertainty by developing an adaptive learning scheme; (c) the uncertainty issues emerging when considering networked systems such as the presence of delays and packet dropouts in the communication networks. The proposed architecture considers in an integrated way the various components of complex distributed systems such as the physical environment, the sensor level, the fault diagnosers, and the communication networks. Finally, some actions taken after the detection of a fault, such as the identification of the fault location and its magnitude or the learning of the fault function, are illustrated

Newtype single-layer magnetic semiconductor in transition-metal dichalcogenides VX 2 (X = S, Se and Te)

We present a newtype 2-dimensional (2D) magnetic semiconductor based on transition-metal dichalcogenides VX2 (X = S, Se and Te) via first-principles calculations. The obtained indirect band gaps of monolayer VS2, VSe2, and VTe2 given from the generalized gradient approximation (GGA) are respectively 0.05, 0.22, and 0.20 eV, all with integer magnetic moments of 1.0 μB. The GGA plus on-site Coulomb interaction U (GGA + U) enhances the exchange splittings and raises the energy gap up to 0.38~0.65 eV. By adopting the GW approximation, we obtain converged G0W0 gaps of 1.3, 1.2, and 0.7 eV for VS2, VSe2, and VTe2 monolayers, respectively. They agree very well with our calculated HSE gaps of 1.1, 1.2, and 0.6 eV, respectively. The gap sizes as well as the metal-insulator transitions are tunable by applying the in-plane strain and/or changing the number of stacking layers. The Monte Carlo simulations illustrate very high Curie-temperatures of 292, 472, and 553 K for VS2, VSe2, and VTe2 monolayers, respectively. They are nearly or well beyond the room temperature. Combining the semiconducting energy gap, the 100% spin polarized valence and conduction bands, the room temperature TC, and the in-plane magnetic anisotropy together in a single layer VX2, this newtype 2D magnetic semiconductor shows great potential in future spintronics

Recommendations for the diagnosis of pediatric tuberculosis

Tuberculosis (TB) is still the world's second most frequent cause of death due to infectious diseases after HIV infection, and this has aroused greater interest in identifying and managing exposed subjects, whether they are simply infected or have developed one of the clinical variants of the disease. Unfortunately, not even the latest laboratory techniques are always successful in identifying affected children because they are more likely to have negative cultures and tuberculin skin test results, equivocal chest X-ray findings, and atypical clinical manifestations than adults. Furthermore, they are at greater risk of progressing from infection to active disease, particularly if they are very young. Consequently, pediatricians have to use different diagnostic strategies that specifically address the needs of children. This document describes the recommendations of a group of scientific societies concerning the signs and symptoms suggesting pediatric TB, and the diagnostic approach towards children with suspected disease

Synthesis and optical characterisation of platinum(II) poly-yne polymers incorporating substituted 1,4-diethynylbenzene derivatives and an investigation of the intermolecular interactions in the diethynylbenzene molecular precursors

A series of 1,4-diethynylbenzene (1) derivatives, H-C≡C-R-C≡C-H with R = C6H3NH2 (2), C6H3F (3), C6H2F2-2,5 (4), C6F4 (5), C6H2(OCH3)2-2,5 (6) and C6H2(OnC8H17) 2-2,5 (7) has been synthesised and their crystal structures determined by single crystal (2-5) or powder (6, 7) X-ray diffraction. The C≡CH⋯πC≡=C hydrogen bonds dominating structure 1 are gradually replaced by C≡C-H⋯F ones with the increase of fluorination (3 → 5), or completely replaced by C≡CH⋯N and NH⋯πC≡C bonds in 2, and C≡CH⋯O in 6 and 7. The related platinum-based polymers, trans-[-Pt(PnBu3)2-C≡C-R-C≡C-]) n (R = as above and C6H4,) have been prepared and characterised by spectroscopic methods and thermogravimetry, which show that the amino- and methoxy-derivatives have lowest thermal stability while the fluorinated ones exhibit increasing thermal stability with increasing fluorination. Optical spectroscopic measurements reveal that substituents on the aromatic spacer group do not create strong donor-acceptor interactions along the rigid backbone of the organometallic polymers

NMR-based metabolomics: quality and authenticity of plant-based foods

Nowadays metabolomics is a widely accepted approach in several scientific disciplines, especially in food science. The possibility to identify a wide range of metabolites (untargeted analysis) allowed to evaluate various food characteristics, regarding quality, adulteration, geographical origin, as well as secondary species-specific metabolites endowed with nutraceutical properties. In the present chapter, latest findings of plant-based foods investigated by NMR-based metabolomics are presented. Almost all of the recent studies were focused on quality assessment and authenticity; different aspects such as geographical origin, metabolic modifications upon stress, nutraceutical properties, and fraud detection are described as well. The here reported plant-based foods are balsamic and traditional balsamic vinegars, cereals, cocoa, coffee, fruits, legumes, spices, vegetables and vegetable oils, wine, beer, and spirits. A brief paragraph is concerning organic and conventional foods, which is a new growing scientific field of interest for researchers encouraged by the increasing consumers’ demand. The results here reported testify the capability and the power of this approach thus endorsing NMR spectroscopy as a valid alternative or complement to the chemical and physical analysis nowadays routinely applied for the quality assessment