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981.
O Bernard B Chachuat A Hélias B Le Dantec B Sialve J-P Steyer L Lardon P Neveu S Lambert J Gallop M Dixon P Ratini A Quintabà S Frattesi J M Lema E Roca G Ruiz J Rodriguez A Franco P Vanrolleghem U Zaher D J W De Pauw K De Neve K Lievens D Dochaine O Schoefs H Fibrianto R Farina V Alcaraz Gonzalez V Gonzalez Alvarez P Lemaire J A Martinez F Esandi O Duclaud J F Lavigne 《Water science and technology》2005,52(1-2):457-464
The TELEMAC project brings new methodologies from the Information and Science Technologies field to the world of water treatment. TELEMAC offers an advanced remote management system which adapts to most of the anaerobic wastewater treatment plants that do not benefit from a local expert in wastewater treatment. The TELEMAC system takes advantage of new sensors to better monitor the process dynamics and to run automatic controllers that stabilise the treatment plant, meet the depollution requirements and provide a biogas quality suitable for cogeneration. If the automatic system detects a failure which cannot be solved automatically or locally by a technician, then an expert from the TELEMAC Control Centre is contacted via the internet and manages the problem. 相似文献
982.
Practical limitations of subwavelength resolution using negative-refractive-index transmission-line lenses 总被引:3,自引:0,他引:3
Previously, we have demonstrated both analytically and experimentally subwavelength imaging using a negative-refractive-index lens made of a periodically L, C loaded transmission line (TL) network. This loaded transmission line network has been referred to as the dual TL lens. Here, we consider the limitations on subwavelength imaging imposed by impedance mismatches and the component losses of a practical dual TL lens. Simple expressions for estimating the resolving capability of a dual TL lens are given. It is found that the resolution enhancement of the dual lens is proportional to the quality factor of the series loading capacitors divided by the electrical thickness of the lens. The effective material parameters of the dual TL lens are also derived so that these expressions can be directly related to those of previous studies considering uniform and isotropic left-handed lenses. Finally, the resolving capability of an experimental lens that achieves subwavelength imaging is theoretically predicted. These theoretical predictions are then directly compared to previously reported experimental results. 相似文献
983.
J. Chen J. B. Xu K. Xue J. An N. Ke W. Cao H. B. Xia J. Shi D. C. Tian 《Microelectronics Reliability》2005,45(1):137-142
Transition-metal compound TiC60 thin films were grown by co-deposition from two separated sources of fullerene C60 powder and titanium. Study of structural properties of the films, by Raman spectroscopy, atomic force microscopy, and scanning tunneling spectroscopy reveals that the films have a deformed C60 structure with certain amount of sp3 bonds and a rough surface with a large number of nanoclusters. z–V tunnelling spectroscopic measurements suggest that several charge transport mechanisms are involved in as the tip penetrates into the thin film. Conventional field electron emission (FEE) measurements show a high emission current density of 10 mA/cm2 and a low turn-on field less than 8 V/μm, with the field enhancement factors being 659 and 1947 for low-field region and high-field region, respectively. By exploiting STM tunneling spectroscopy, local FEE on nanometer scale has also been characterized in comparison with the conventional FEE. The respective field enhancement factors are estimated to be 99–355 for a gap varying from 36 to 6 nm. The enhanced FEE of TiC60 thin films can be ascribed to structural variation of C60 in the films and the electrical conducting paths formed by titanium nanocrystallites embedded in C60 matrix. 相似文献
984.
This paper presents a technique for characterizing the statistical properties and spectrum of power supply noise using only two on-chip low-throughput samplers. The samplers utilize a voltage-controlled oscillator to perform high-resolution analog-to-digital conversion with minimal hardware. The measurement system is implemented in a 0.13-/spl mu/m process along with a high-speed link transceiver. Measured results from this chip validate the accuracy of the measurement system and elucidate several aspects of power supply noise, including its cyclostationary nature. 相似文献
985.
Remotely powered addressable UHF RFID integrated system 总被引:3,自引:0,他引:3
Curty J.-P. Joehl N. Dehollain C. Declercq M.J. 《Solid-State Circuits, IEEE Journal of》2005,40(11):2193-2202
This paper presents a fully integrated remotely powered and addressable radio frequency identification (RFID) transponder working at 2.45 GHz. The achieved operating range at 4 W effective isotropically radiated power (EIRP) base-station transmit power is 12 m. The integrated circuit (IC) is implemented in a 0.5 /spl mu/m silicon-on-sapphire technology. A state-of-the-art rectifier design achieving 37% of global efficiency is embedded to supply energy to the transponder. The necessary input power to operate the transponder is about 2.7 /spl mu/W. Reader to transponder communication is obtained using on-off keying (OOK) modulation while transponder to reader communication is ensured using the amplitude shift keying (ASK) backscattering modulation technique. Inductive matching between the antenna and the transponder IC is used to further optimize the operating range. 相似文献
986.
A new CMOS VLSI implementation of an asymmetric programmable sigmoid neural activation function, as well as of its derivative, is presented. It consists of two coupled PMOS and NMOS differential pairs with different programmable bias currents that set the upper and lower limits of the sigmoid. The circuit works in the weak inversion region, for low power consumption and exponential envelope, or in strong inversion to achieve higher speeds. The results obtained from the theoretical transfer function, and from the simulations of the circuit implemented in AMI's 0.35 /spl mu/m technology, show a very good match. 相似文献
987.
Dynamic vulcanisation of EPDM/PE-based thermoplastic vulcanisates studied along the extruder axis 总被引:1,自引:0,他引:1
Simple blending and dynamic vulcanisation of EPDM/PE blends using the resol/SnCl2 system was studied in an extruder using a series of sampling devices. The melting of the PE pellets occurs just in front of and in the first kneading zone. Upon complete melting of the PE phase, the EPDM/PE blends reach very quickly their final morphology. Crosslinking of the EPDM phase to high levels occurs already when the PE phase is not yet fully molten. The higher the EPDM content, the higher the viscous dissipation, the higher the melt temperature and, consequently, the higher the crosslinking rate. For the EPDM/PE (50/50; w/w) TPV a transition from continuous via co-continuous to fully dispersed EPDM is observed, which is driven by crosslinking. Although the degree of crosslinking of the EPDM rubber is very high, this does not prevent phase inversion of the blend. The EPDM/PE interface is rather blurred, because PE crystalline lamellae are growing into the EPDM domains, probably because of the high compatibility between PE and EPDM (60 wt% of ethene). This study shows that dynamic vulcanisation in extruders proceeds quite differently from that in batch kneaders, where melting, mixing and crosslinking are separated in time. In extruders mass and heat transport, melting of the thermoplastic, morphology development (including dispersion and phase inversion), distribution and dissolution of (crosslinking) chemicals and crosslinking of the rubber do not occur as independent phenomena, but mutually and/or continuously interact. 相似文献
988.
Pure phase of sillenite structure, Bi12TiO20, was directly synthesized using stoichiometric bismuth (III) nitrate pentahydrate and titanium glycolate by co-precipitation. The influence of pH on the structure of Bi12TiO20 was studied in the pH range of 3–10. The sillenite structure was characterized using XRD and FTIR. The photo-degradation reaction of 4-nitrophenol (4-NP) was used to study photocatalytic activity of Bi12TiO20 as a function of the preparation pH. The rate of decomposition was followed by UV-vis and TOC. The beginning concentration of 4-NP, 44 ppm, decreased to less than 1 ppm within 30 min for all prepared catalysts. It was found that the decomposition rate constant of Bi12TiO20 is six times higher than those of either TiO2 or Bi2O3 under the same conditions. 相似文献
989.
A method of calculating the dynamic deflection of rigidly plastic plates resting on a viscoelastic bed with complex piecewise-smooth support contours composed of sections of straight lines and circles under impact and explosion loading is presented. The general solution, which includes previously known partial solutions for circular and polygonal plates, is obtained. The results of calculation of the deflection of a square hinge-supported plate with rounded corners are presented for the case of the presence and absence of a plastic base.Translated from Problemy Prochnosti, No. 9, pp. 62–66, September, 1991. 相似文献
990.
A combination of concept (the product portfolio and the product life cycle) and empirical research (the PIMS study) can aid in clarifying the key issues involved in the selection of a firm's core strategies. Strategy control is multistage: periodic re-evaluation of strategy alternatives by use of the marketing audit; an analytical framework for control of chosen strategies by breaking down components and reporting their performance variances; and 'marketing segment' analysis for control of the detailed marketing plan.? 相似文献