Search results for " Fault"
showing 10 items of 239 documents
Optical characterization of Mg-doped GaN films grown by metalorganic chemical vapor phase deposition
2000
Scanning electron microscopy, micro-Raman, and photoluminescence (PL) measurements are reported for Mg-doped GaN films grown on (0001) sapphire substrates by low-pressure metalorganic chemical vapor phase deposition. The surface morphology, structural, and optical properties of GaN samples with Mg concentrations ranging from 1019 to 1021 cm−3 have been studied. In the scanning micrographs large triangular pyramids are observed, probably due to stacking fault formation and three-dimensional growth. The density and size of these structures increase with the amount of magnesium incorporated in the samples. In the photoluminescence spectra, intense lines were found at 3.36 and 3.31 eV on the tr…
Structural overprint of a late Paleozoic accretionary system in north-central Chile (34°-35°S) during post-accretional deformation
2009
En la Cordillera de la Costa de Chile, de 36° a 35°S, se encuentra expuesta la arquitectura coherentemente preservada de un prisma de acrecion del Paleozoico tardio, en cercana vecindad a un area entre los 34° y 35°S, donde el mismo esta fuertemente modificado por procesos postacrecionales. Estudiando las desviaciones de la arquitectura original, en esta region pueden ser perfectamente distinguidas estructuras sin- y post acrecionales. Al sur de los 35° se observa un contacto transicional entre dos unidades mayores, el cual refleja un cambio continuo en el modo de acrecion de la cuna acrecional antes de -305 Ma: las metagrauvacas estructuralmente suprayacentes de las series orientales muest…
Power Quality Savings with Controlled Fault-Tolerant Power Converters
2011
Power quality is simply the interaction of electrical power with electrical equipments. If electrical equipments operate correctly and reliably without being damaged or stressed, a suitable level of power quality is assured. On the other hand, if the electrical equipment malfunctions, is unreliable, or is damaged during normal usage, power quality is poor and probably the economical loss could be preeminent over the technical one. In the scenario of the Distributed generation power quality issues will be more- over important because an higher dissemination of power conditioning equip- ment will be requested and this obviously will increase the sources of vulnera- bility for the electrical s…
Deep-rooted “thick skinned” model for the High Atlas Mountains (Morocco). Implications for the structural inheritance of the southern Tethys passive …
2006
A re-interpretation of the deep structure of the High Atlas is presented through integration of geophysical and geological data, highlighting the architectural significance of the southern Tethys palaeomargin. Previous crustal models suggest the occurrence of a flat intra-crustal detachment at a depth of � 20 km, a zone where surface thrusts merge and below which the lower High Atlas crust appears continuous. However, within this study seismic refraction data, electrical resistivity surveys and gravity modelling all appear to detect a jump in crustal thickness between the High Atlas and the northern plains. We interpret these data as penetration by thrusts within the ‘‘South-Atlasic fault’’…
Geochemical characterisation of gases along the dead sea rift: Evidences of mantle-co2 degassing
2016
International audience; The Dead Sea Transform (DST) fault system, where a lateral displacement between the African and Arabian plates occurs, is characterised by anomalous heat flux in the Israeli area close to the border with Syria and Jordan. The concentration of He and CO2, and isotopic composition of He and total dissolved inorganic carbon were studied in cold and thermal waters collected along the DST, in order to investigate the source of volatiles and their relationship with the tectonic framework of the DST. The waters with higher temperature (up to 57.2 °C) are characterised by higher amounts of CO2 and helium (up to 55.72 and 1.91 * 10-2 cc l-1, respectively). Helium isotopic dat…
Risk Analysis of a Fuel Storage Terminal Using HAZOP and FTA
2017
[EN] The size and complexity of industrial chemical plants, together with the nature of the products handled, means that an analysis and control of the risks involved is required. This paper presents a methodology for risk analysis in chemical and allied industries that is based on a combination of HAZard and OPerability analysis (HAZOP) and a quantitative analysis of the most relevant risks through the development of fault trees, fault tree analysis (FTA). Results from FTA allow prioritizing the preventive and corrective measures to minimize the probability of failure. An analysis of a case study is performed; it consists in the terminal for unloading chemical and petroleum products, and t…
Algorithmic Complexity Vulnerability Analysis of a Stateful Firewall
2016
Algorithmic complexity vulnerabilities are an opportunity for an ad-versary to conduct a sophisticated kind of attack i.e. on network infrastructure services. Such attacks take advantage of worst case time or space complexity of algorithms implemented on devices in their software. In this paper we address potential risks introduced by such algorithmic behavior in computer networks in particular on a stateful firewall. First we introduce the idea and theoretical background for the attack. We then describe in full detail a successfully con-ducted attack which takes advantage of the worst case computational complexi-ty of O(n2) of a hash table data structure used to store active sessions. The …
Seismogenic rotational slumps and translational glides in pelagic deep-water carbonates. Upper Tithonian-Berriasian of Southern Tethyan margin (W Sic…
2017
Abstract Soft-sediment deformation structures (SSDSs), which reflect sediment mobilization processes, are helpful to identify punctual events of paleoenvironmental stresses. In the upper Tithonian-Berriasian calpionellid pelagic limestone of the Lattimusa Fm. outcropping in the Barracu section (W Sicily), paleoenvironmental restoration reveals the occurrence of a deep-water flat basin, characterised by undeformed planar bedding, laterally passing to a gentle slope where the deformed horizons alternate with undeformed beds. Here, two types of gravity slides have been differentiated on the basis of different kinds of SSDSs, brittle deformation, involved lithofacies, geometry and morphology. T…
A Smart Sensing Method for Real- Time Monitoring of Low Voltage Series-Arc-Fault
2020
This paper proposes a smart sensing method for real-time monitoring of low voltage series arc fault. It is based on the wavelet coefficient mean-difference algorithm and the four spikes appearing within two fundamental periods criterion with adaptive threshold. The method also uses the hard thresholding wavelet denoising with the universal threshold. An arc fault factor and a load adaptation factor are introduced and combined with a correction factor, so allowing the selection of the adaptive threshold in real-time and the series arc fault detection.
Electrical Safety of Resonant Grounding
2019
The resonant grounding is one of the possible methods of system neutral grounding for the medium-voltage distribution. IEEE standards do define this grounding configuration, but important advantages and drawbacks of the resonant grounding might not be fully known, due to its rather uncommon application in North America. On the other hand, resonant grounding in Europe is imposed by the increased requirements for power quality, especially for medium-voltage industrial users, and imposed to electric utilities by Regulatory Authorities, with the purpose to protect the interests of users and consumers. Level of the continuity of the service, magnitude and phase of ground-fault currents, magnitud…