129 resultados para SI(LI) DETECTOR
Resumo:
El lideratge és el conjunt de capacitats que una persona té per influir en les persones o en un grup de persones determinat, per a l’assoliment de metes i objectius predeterminats. El líder te la capacitat de prendre la iniciativa, gestionar, convocar, promoure, incentivar, motivar i avaluar a un grup o equip. Capacitat fa referència als recursos i aptituds que té un individu per a exercir una determinada tasca o comesa (no ens diu res de si són innates o adquirides) per tant ens fiquem en un “lio” (habilitats, competències, aptituds, etc.. etc…). Parlem de coneixement. En l’àmbit de l’economia del coneixement “es allò que sabem (encara que no sapiguem que ho sabem) que ens capacita per a l’acció”. Aquí ens tornem a trobar el coneixement innat i el adquirit. En aquest cas, “l’acció” son precisament el que han de fer les persones en relació a un objectiu. En el lideratge la capacitat o coneixement es comportamental i per tant per adquirir-lo cal aprendre comportaments (simulació - estandardització, entrenament, es el mon de l’experiència). Canviar els comportaments es el mes difícil. Per una Escola aniria per formar en el lideratge li aniria millor que estiguéssim parlant de coneixements “memoristics” o de procediment que son molt mes fàcils de formar.
Resumo:
Tot i que els interessos de Pierre Vilar, en el curs de la seva llarga vida professional, van ser molt més amplis, em penso que no és cap exageració afirmar que el segle XVIII fou el seu segle. En tot cas, el que segur que no és exagerat és dir que els investigadors catalans sobre el segle XVIII han estat aquells sobre qui la influència de l’obra de Vilar més s’ha fet sentir. Aquest fet és fàcil d’explicar. En primer lloc, perquè va ser la documentació del segle XVIII la que Pierre Vilar va explorar i treballar de primera mà en els arxius i la que va alimentar el miler de pàgines dels volums tercer i quart –segon i tercer si pensem en l’edició francesa original– de la seva voluminosa tesi doctoral. En segon lloc, perquè en aquest segle Vilar va cercar-hi els fonaments de les societats contemporànies. De fet, i no podia ser d’altra manera tenint en compte el mètode d’anàlisi històrica de Pierre Vilar, la recerca empírica sobre el segle XVIII català va fer-li plantejar el “problema” històric dels “fonaments econòmics de les estructures nacionals”
Resumo:
El treball es centra principalment en el disseny de la instal·lació geotèrmica exterior i del terra radiant de l'interior. El disseny es basa en aconseguir el confort de calefacció i s'aprofita el fet de que s'utilitza un sistema reversible per aportar el màxim confort durant l'èpocade refrigeració. Es realitza un estudi de les possibles alternatives per a la instal·lació, també s'observaran els aparells i accessoris escollits per a la implantació de la instal·lació.
Resumo:
In this paper, the sensor of an optical mouse is presented as a counterfeit coin detector applied to the two-Euro case. The detection process is based on the short distance image acquisition capabilities of the optical mouse sensor where partial images of the coin under analysis are compared with some partial reference coin images for matching. Results show that, using only the vision sense, the counterfeit acceptance and rejection rates are very similar to those of a trained user and better than those of an untrained user.
Resumo:
The rate of leaf appearance of barley varies substantially with time of sowing. This variation has been related to both the length and the rate of change of photoperiod at the time of plant emergence. An outdoor pot experiment was conducted to test if rate of change of photoperiod directly affects phasic development and rate of leaf emergence of spring barley. Two photoperiod-sensitive cultivars (Bandulla and Galleon) were subjected to five photoperiod regimes: two constant photoperiods, of 14 and 15·5 h, and three different rates of change of photoperiod of c. 2, 9 and 13 min/day from seedling emergence to awn initiation. Photoperiod treatments significantly affected the duration from seedling emergence to awn initiation in both cultivars. Rate of change of photoperiod did not affect the rate of development towards awn initiation independently of the absolute daylength it produced. Although Bandulla had a longer duration than Galleon at any photoperiod regime, the cultivars did not vary in their sensitivity to photoperiod. When this phase was divided into the leaf initiation (LI) and spikelet initiation (SI) phases, it was evident that the sensitivity to photoperiod was not constant, being in general higher during the SI than during the LI phase. However, the magnitude of the change in sensitivity was cultivar-dependent, indicating that sensitivity to photoperiod during the different phases could be under independent genetic control. Final numbers of primordia (leaves together with maximum spikelet number) were negatively affected by increasing photoperiods, but once again, there was no evidence of any effect of the rate of change of photoperiod which was independent of the average photoperiod. Both cultivars showed similar sensitivities for final leaf number but maximum spikelet number was more sensitive to photoperiod in Galleon than in Bandulla. Highly significant linear relationships between leaf number and thermal time were found for all combinations of cultivars and photoperiod regimes (r2 > 0·98). The rate of leaf appearance (RLA) was similar for both cultivars (c. 0·0185 leaves/°Cd) and did not alter during plant development or in response to the change in photoperiod at awn initiation. The range in RLA was greater for Galleon (0·0170–0·0205 leaves/°Cd) than for Bandulla (0·0173–0·0186 leaves/°Cd). Neither of these cultivars exhibited a significant relationship between rate of leaf emergence and photoperiod or rate of change of photoperiod. The lack of significant relationships between RLA and length or rate of change of photoperiod is in contrast with previous reports using time of sowing as a main treatment.
Resumo:
Per entendre el possible impacte del tren d'alta velocitat a Lleida s'han analitzat exemples de França (línia París-Lió) i Alemanya (Mannheim), on el tren d'alta velocitat competeix favorablement amb l'autopista en trajectes de més d'una hora o una hora i mitja, i amb l'avió en trajectes de fins a 3 hores. Les estacions urbanes de les grans aglomeracions, dotades amb un bon transport públic, se'n beneficien de la seva centralitat i de la realimentació mútua entre serveis, mentre que les situades a fora dels nuclis han vist com el servei inicial s'ha degradat per manca de clientela suficient. L'arribada del tren d'alta velocitat a una estació central s'aprofita sovint per renovar-la, cosa que afecta també el seu entorn i, de vegades, el barri sencer. El tren d'alta velocitat, doncs, augmenta la centralitat i, en alguns casos, motiva una descentralització concentrada de les metròpolis a les ciutats mitjanes. A més, provoca noves pautes de localització i afavoreix un funcionament més eficaç de les empreses dels sectors sensibles. El sector agroalimentari i alguns serveis presents a Lleida poden gaudir d'aquest afavoriment si es tecnifiquen i se situen en un grau de qualificació alt.
Resumo:
Aquest document descriu una aplicació per a dispositius Android. L'aplicació IngredientApp és un intent d'autocontrolar el que comprem, fem servir o mengem. Es tracta d'una aplicació a la qual s'hi defineixen unes preferències sobre els ingredients dels productes i, fent servir un smartphone, sense haver de mirar la llista d'ingredients, l'aplicatiu li advertirà si el producte compleix els seus criteris.
Resumo:
In this work, we investigate heterojunction emitters deposited by Hot-Wire CVD on p-type crystalline silicon. The emitter structure consists of an n-doped film (20 nm) combined with a thin intrinsic hydrogenated amorphous silicon buffer layer (5 nm). The microstructure of these films has been studied by spectroscopic ellipsometry in the UV-visible range. These measurements reveal that the microstructure of the n-doped film is strongly influenced by the amorphous silicon buffer. The Quasy-Steady-State Photoconductance (QSS-PC) technique allows us to estimate implicit open-circuit voltages near 700 mV for heterojunction emitters on p-type (0.8 Ω·cm) FZ silicon wafers. Finally, 1 cm 2 heterojunction solar cells with 15.4% conversion efficiencies (total area) have been fabricated on flat p-type (14 Ω·cm) CZ silicon wafers with aluminum back-surface-field contact.
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We have studied the current transport and electroluminescence properties of metal oxide semiconductor MOS devices in which the oxide layer, which is codoped with silicon nanoclusters and erbium ions, is made by magnetron sputtering. Electrical measurements have allowed us to identify a Poole-Frenkel conduction mechanism. We observe an important contribution of the Si nanoclusters to the conduction in silicon oxide films, and no evidence of Fowler-Nordheim tunneling. The results suggest that the electroluminescence of the erbium ions in these layers is generated by energy transfer from the Si nanoparticles. Finally, we report an electroluminescence power efficiency above 10−3%. © 2009 American Institute of Physics. doi:10.1063/1.3213386
Resumo:
Electrically driven Er3+ doped Si slot waveguides emitting at 1530 nm are demonstrated. Two different Er3+ doped active layers were fabricated in the slot region: a pure SiO2 and a Si-rich oxide. Pulsed polarization driving of the waveguides was used to characterize the time response of the electroluminescence (EL) and of the signal probe transmission in 1 mm long waveguides. Injected carrier absorption losses modulate the EL signal and, since the carrier lifetime is much smaller than that of Er3+ ions, a sharp EL peak was observed when the polarization was switched off. A time-resolved electrical pump & probe measurement in combination with lock-in amplifier techniques allowed to quantify the injected carrier absorption losses. We found an extinction ratio of 6 dB, passive propagation losses of about 4 dB/mm, and a spectral bandwidth > 25 nm at an effective d.c. power consumption of 120 μW. All these performances suggest the usage of these devices as electro-optical modulators.
Resumo:
In this study, (011)-highly oriented Sr, Nb co-doped BiFeO3 (BFO) thin films were successfully grown on SrRuO3/Si substrates by rf-magnetron sputtering. The presence of parasite magnetic phases was ruled out based on the high resolution x-ray diffraction data. BFO films exhibited a columnar-like grain growth with rms surface roughness values of 5.3 nm and average grain sizes of 65-70 nm for samples with different thicknesses. Remanent polarization values (2Pr) of 54 lC cm 2 at room temperature were found for the BFO films with a ferroelectric behavior characteristic of an asymmetric device structure. Analysis of the leakage mechanisms for this structure in negative bias suggests Schottky injection and a dominant Poole-Frenkel trap-limited conduction at room temperature. Oxygen vacancies and Fe3þ/Fe2þ trap centers are consistent with the surface chemical bonding states analysis from x-ray photoelectron spectroscopy data. The (011)-BFO/ SrRuO3/Si film structure exhibits a strong magnetic interaction at the interface between the multiferroic film and the substrate layer where an enhanced ferromagnetic response at 5 K was observed. Zero-field cooled (ZFC) and field cooled (FC) magnetization curves of this film system revealed a possible spin glass behavior at spin freezing temperatures below 30 K depending on the BFO film thickness.
Resumo:
High resolution x-ray photoelectron spectroscopy has been used to determine the valence band alignment at ultrathin SiO2/Si interfaces. In the oxide thickness range 1.6-4.4 nm the constant band-offset values of 4.49 and 4.43 eV have been obtained for the dry SiO2/Si(100) and the wet SiO2/Si(100) interfaces, respectively. The valence band alignment of dry SiO2/Si(111) (4.36 eV) is slightly smaller than the case of the dry SiO2/Si(100) interface.
Resumo:
In this paper we design and develop several filtering strategies for the analysis of data generated by a resonant bar gravitational wave (GW) antenna, with the goal of assessing the presence (or absence) therein of long-duration monochromatic GW signals, as well as the eventual amplitude and frequency of the signals, within the sensitivity band of the detector. Such signals are most likely generated in the fast rotation of slightly asymmetric spinning stars. We develop practical procedures, together with a study of their statistical properties, which will provide us with useful information on the performance of each technique. The selection of candidate events will then be established according to threshold-crossing probabilities, based on the Neyman-Pearson criterion. In particular, it will be shown that our approach, based on phase estimation, presents a better signal-to-noise ratio than does pure spectral analysis, the most common approach.