Transient Stability Hierarchical Control in Multimachine Power Systems

The authors present the optimal transient stability control problem in a hierarchical structure for multimachine power systems. The two-level structure retains the local closed-loop controls, thereby easing its implementation on existing systems. The formulation accounts for nonlinearities and interconnections, and the optimization of the system transient performance is obtained with less computational effort. Since the computations are distributed among the many local feedback subsystems, the storage and solution times are considerably less than those required by a single overall centralized controller. This advantage becomes much stronger as the system size increases. For illustration purposes, this technique was applied successfully to a four-machine syste

Diques lamprofíricos norteados con facies brechoidales eruptivas en la región de La Palamera de Ávila (Sistema Central español)

[Resumen] Según direcciones N-S afloran diques diabásicos y lamprofíricos en los sectores centrales del Sistema Central, estos últimos, muy localmente (Sierra de La Paramera), presentan facies brechoidales eruptivas que podrían explicarse como fenómenos de tipo diatrema, generados en un proceso de fluidizaci6n del magma lamprofírico. Los lamprófiros pueden considerarse términos alcalinos, en cuyas facies brechoidales engloban gran cantidad de xenolitos, tanto de las rocas encajantes (granitos, pórfidos graníticos, apIopegmatitas, ...), como de rocas esquistosas y granul1ticas varias (charnockitas, granoblastitas de granate y rutilo, ... ), de niveles más profundos[Abstract] In the central part oE the Sistema Central thelamprophyre dikes of N-S direction locally show (Sierra de La Paramera) an eruptive breccia facies that ve explain by a fluidization process similar to diatreme types. This lamprophyres, alkaline in composition, contain a lot oE xenoliths in that breccia facies. They are not also wall rocks xenoliths (granites, microgranites, aplopegmatites, ... ) but schistose and granulitic types (foliated or massives with charnockitic character, granoblastites with garnet and rutile, ... ), from deeper level

A parallel strategy for implementing real-time expert systems using CLIPS

As evidenced by current literature, there appears to be a continued interest in the study of real-time expert systems. It is generally recognized that speed of execution is only one consideration when designing an effective real-time expert system. Some other features one must consider are the expert system's ability to perform temporal reasoning, handle interrupts, prioritize data, contend with data uncertainty, and perform context focusing as dictated by the incoming data to the expert system. This paper presents a strategy for implementing a real time expert system on the iPSC/860 hypercube parallel computer using CLIPS. The strategy takes into consideration not only the execution time of the software, but also those features which define a true real-time expert system. The methodology is then demonstrated using a practical implementation of an expert system which performs diagnostics on the Space Shuttle Main Engine (SSME). This particular implementation uses an eight node hypercube to process ten sensor measurements in order to simultaneously diagnose five different failure modes within the SSME. The main program is written in ANSI C and embeds CLIPS to better facilitate and debug the rule based expert system

Nuts and bolts of ITRAQ-based quantitative analysis

Comunicaciones a congreso

Geochronology and trace element chemistry of zircon and garnet from granulite xenoliths: Constraints on the tectonothermal evolution of the lower crust under central Spain

The nature of the lower crust under central Spain can be constrained from the study of deep-seated xenoliths entrapped within ultrabasic alkaline dykes of upper Permian age. These xenoliths are predominantly metaigneous peraluminous felsic granulites. Cathodoluminescence (CL) imaging of zircons from these rocks reveals a complex internal structure with magmatic inherited cores (sometimes showing convoluted or blurred oscillatory zoning) and metamorphic homogeneous domains. U–Pb SHRIMP dating shows that zircon core formation took place in several stages, mainly during the Upper Proterozoic (674–542 Ma). These ages are likely related to a pre-Variscan (Cadomian) tectono-magmatic episode. Most of the geochronological data correspond to metamorphic unzoned grains and rims formed during the Variscan orogeny (274–320 Ma). This time period greatly overlaps the intrusion ages of the granitic batholith in central Spain, reinforcing the hypothesis that the granulites from the lower crust might be genetically related to the extraction of the felsic magmas. Trace element concentrations in zircon and accompanying garnets, determined by Laser Ablation ICP-MS, suggest that both phases were in equilibrium in the studied granulites. HREE partition coefficients estimated in one sample are very close to 1, resembling results from previous studies in similar granulitefacies rocks. The composition of the HREE-rich magmatic zircon cores contrast markedly with metamorphic grains equilibrated with garnet (GdN/YbNN0.37). It is also possible to distinguish several types of metamorphic zircon rims on the basis of Th, U and REE composition. Temperatures estimated on these latter domains using the Ti-in zircon thermometer indicate that they formed during granulite-facies metamorphism. Zircons with high Th/U ratios (2.7–3.3) yield high-T estimates (~1000 °C) and older ages (283–320 Ma), whereas zircons with low Th/U ratios (0.04–0.38) give lower temperatures (900–950 °C) and ages (274–283 Ma). The variation in Th/U values and Ce and Eu anomalies in zircons seems to be highly influenced by element availability during metamorphic reactions and partitioning with co-existing minerals, such as monazite and feldspar. The modification of zircon geochemistry and the relationship between the temperature of crystallization and age implies a significant variation of the metamorphic conditions associated with the cooling stage at the end of the Variscan orogeny

Investigating radiatively driven, magnetized plasmas with a university scale pulsed-power generator

We present first results from a novel experimental platform which is able to access physics relevant to topics including indirect-drive magnetised ICF; laser energy deposition; various topics in atomic physics; and laboratory astrophysics (for example the penetration of B-fields into HED plasmas). This platform uses the X-Rays from a wire array Z-Pinch to irradiate a silicon target, producing an outflow of ablated plasma. The ablated plasma expands into ambient, dynamically significant B-fields (~5 T) which are supported by the current flowing through the Z-Pinch. The outflows have a well-defined (quasi-1D) morphology, enabling the study of fundamental processes typically only available in more complex, integrated schemes. Experiments were fielded on the MAGPIE pulsed-power generator (1.4 MA, 240 ns rise time). On this machine a wire array Z-Pinch produces an X-Ray pulse carrying a total energy of ~15 kJ over ~30 ns. This equates to an average brightness temperature of around 10 eV on-target

A strategic reflection for the management and implementation of CAR-T therapy in Spain: an expert consensus paper

CAR-T cell therapy represents a therapeutic revolution in the prognosis and treatment of patients with certain types of hematological cancer. However, they also pose new challenges in the healthcare, regulatory and financial fields. The aim of the RET-A project was to undertake a strategic reflection on the management of CAR-T therapies within the Spanish National Health System, to agree on recommendations that will help to better deal with the new context introduced by these cell therapies in the present and in the future. This think tank involved 40 key agents and opinion leaders. The experts identified three great challenges for implementing advanced therapies in Spain: therapeutic individualisation, with a multidisciplinary approach; acceleration of access times, by minimizing bureaucracy; and increase in the number of centers qualified to manage the CAR-T therapies in the NHS. The experts agreed on the ideal criteria for designating those qualified centers. They also agreed on a comprehensive CAR-T care pathway with the timings and roles which would ideally be involved in each part of the process.This study was funded by Gilead Sciences, Inc.Peer reviewe

Nature and evolution of the lower crust under central Spain: Inferences from granulite xenoliths (Calatrava Volcanic Field-Spanish central system)

So far, the nature and evolution of the lower crust under central Spain have been constrained mainly on the basis of a heterogeneous suite of granulite xenoliths from the Spanish Central System (SCS). In recent years, ultramafic volcanics from the Calatrava Volcanic Field (CVF) have also provided deep-seated crustal xenoliths which have not been studied in detail. Our data, combining mineral, whole-rock and isotopic geochemistry with U–Pb–Hf isotope ratios in zircons from the CVF and SCS xenoliths, highlight the felsic composition of the lower crust under central Iberia. A number of the Calatrava xenoliths represents Variscan igneous protoliths, which are a minor population in the SCS, and were likely formed by crystallisation of intermediate and felsic melts in the lower crust during the Variscan orogeny (leucodiorite protolith age of 314 ± 3 Ma and leucogranite protolith age of 308 ± 2.5 Ma). U–Pb data of metamorphic zircons show that granulite-facies metamorphism mainly occurred from 299 to 285 Ma in both areas. These ages are slightly younger than those of granitic intrusions that could be genetically related to the granulitic residue, which points to a main role of U–Pb isotope resetting in lower crustal zircons during HT or UHT conditions. The zircon U–Pb–Hf isotopic ratios support the idea that the lower crust in central Iberia consists mainly of Ordovician–Neoproterozoic metaigneous and metasedimentary rocks associated with the Cadomian continental arc of northern Gondwana. These rocks provide evidence of mixing between juvenile magmas and an enriched crustal component, ultimately extracted from an Eburnean crust. Other more evolved components present in detrital zircons are likely related to recycling of Archean crust derived from North Africa cratonic terranes