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11.
In the frame of the activities related to ITER divertor R&D, ENEA C.R. Brasimone was in charge by Fusion For Energy (F4E) to perform the assembly, the hydraulic tests and the theoretical simulation of the hydraulic behavior of the full scale divertor cassette prototype. The objective of these activities was aimed at the investigation of the thermal-hydraulic behavior of the full-scale divertor cassette both under steady state condition and during draining and drying operational transient. In particular, the steady state tests were focused on finally check whether the hydraulic design of the divertor components is able to ensure a uniform and proper cooling for the plasma facing components, with an acceptable pressure drop; whilst the transient ones were aimed at defining proper procedures for draining and drying the divertor cassette as well as for refilling it with water.This paper presents the results of the steady state and transient hydraulic experimental test campaigns performed at ENEA C.R. Brasimone as well as the relevant numerical analysis performed at the Department of Nuclear Engineering of the University of Palermo adopting the RELAP5 Mod3.3 thermal-hydraulic system code.  相似文献   
12.
Spoken language understanding (SLU) aims at extracting meaning from natural language speech. Over the past decade, a variety of practical goal-oriented spoken dialog systems have been built for limited domains. SLU in these systems ranges from understanding predetermined phrases through fixed grammars, extracting some predefined named entities, extracting users' intents for call classification, to combinations of users' intents and named entities. In this paper, we present the SLU system of VoiceTone/spl reg/ (a service provided by AT&T where AT&T develops, deploys and hosts spoken dialog applications for enterprise customers). The SLU system includes extracting both intents and the named entities from the users' utterances. For intent determination, we use statistical classifiers trained from labeled data, and for named entity extraction we use rule-based fixed grammars. The focus of our work is to exploit data and to use machine learning techniques to create scalable SLU systems which can be quickly deployed for new domains with minimal human intervention. These objectives are achieved by 1) using the predicate-argument representation of semantic content of an utterance; 2) extending statistical classifiers to seamlessly integrate hand crafted classification rules with the rules learned from data; and 3) developing an active learning framework to minimize the human labeling effort for quickly building the classifier models and adapting them to changes. We present an evaluation of this system using two deployed applications of VoiceTone/spl reg/.  相似文献   
13.
OBJECTIVES: To compare the long term metabolic effects of two diets for treating hyperlipidaemia. DESIGN: Randomised controlled study: after three weeks of normal (control) diet, subjects were randomly allocated to one of two test diets and followed up for six months. SETTING: Lipid clinic of tertiary referral centre in Naples. SUBJECTS: 63 subjects with primary type IIa and IIb hyperlipoproteinaemia entered the study, and 44 completed it. Exclusion criteria were taking drugs known to influence lipid metabolism, evidence of cardiovascular disease, homozygous familial hypercholesterolaemia, and body mass index over 30. INTERVENTIONS: Two test diets with reduced saturated fat (8%) and cholesterol (approximately 200 mg/day): one was also low in total fat and rich in carbohydrate and fibre, and the other was low in carbohydrate and fibre and rich in polyunsaturated and monounsaturated fats. MAIN OUTCOME MEASURES: Fasting plasma lipid and lipoprotein concentrations; blood glucose, insulin, and triglyceride concentrations before and after a test meal. RESULTS: In comparison with the control diet, both test diets induced significant and similar decreases in low density lipoprotein cholesterol concentrations (by a mean of 0.72 (SE 0.15) mmol/l, P < 0.001, for low total fat diet; by 0.49 (0.18) mmol/l, P < 0.05, for high unsaturated fat diet) and plasma triglyceride concentrations (by 0.21 (0.09) mmol/l, P < 0.05, for low total fat diet; by 0.39 (0.15) mmol/l, P < 0.05, for high unsaturated fat diet), while high density lipoprotein cholesterol concentrations after fasting and plasma glucose and insulin concentrations during test meals were not modified by either diet. CONCLUSIONS: Both test diets are suitable (alone or in combination) for treatment of hypercholesterolaemia.  相似文献   
14.
The mmr gene, cloned from Mycobacterium tuberculosis, was shown to confer to Mycobacterium smegmatis resistance to tetraphenylphosphonium (TPP), erythromycin, ethidium bromide, acriflavine, safranin O, and pyronin Y. The gene appears to code for a protein containing four transmembrane domains. Studies of [3H]TPP intracellular accumulation strongly suggest that the resistance mediated by the Mmr protein involves active extrusion of TPP.  相似文献   
15.
Blakley R  Riccardi M 《Applied optics》2003,42(10):1876-1881
A family of catadioptric telescopes is investigated, characterzied with two-element, full-aperture afocal corrector lenses and aspherical, focusing, primary mirrors or primary-secondary mirror combination. Third-order aberration and design equation are provided for anastigmatic systems in which corrector position must be a free parameter, forcing the consideration of aspherics on the mirrored surfaces.  相似文献   
16.
SiOxCyHz thin films were deposited from hexamethyldisiloxane (HMDSO)/O2 mixtures in a parallel plate, capacitively coupled, RF plasma reactor. Polyethylene terephthalate (PET), Si(1 0 0) wafers and KBr tablets were chosen as substrates. Effect of HMDSO/O2 ratio, total treatment pressure and power input on the properties of the deposited films were investigated. The structure and bondings were studied by means of Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Wettability characteristics of the deposited thin films were investigated by means of water droplet contact angle measurements. Surface morphology was investigated with atomic force microscopy. Barrier properties of the SiOxCyHz thin films were investigated by measuring the water vapour transmission rate of the coated PET substrates. Correlations between the characteristics of the deposited film and their barrier properties were discussed.  相似文献   
17.
Bismuth titanate (Bi4Ti3O12—BIT) films were evaluated for use as lead-free piezoelectric thin-films in micro-electromechanical systems. The films were grown by the polymeric precursor method on Pt/Ti/SiO2/Si (1 0 0) (Pt) bottom electrodes at 700 °C for 2 h in static air and oxygen atmospheres. The domain structure was investigated by piezoresponse force microscopy (PFM). Annealing in static air leads to better ferroelectric properties, higher remanent polarization, lower drive voltages and higher piezoelectric coefficient. On the other hand, oxygen atmosphere favors the imprint phenomenon and reduces the piezoelectric coefficient dramatically. Impedance data, represented by means of Nyquist diagrams, show a dramatic increase in the resistivity for the films annealed in static air atmopshere.  相似文献   
18.
19.
The curing reaction of an epoxy resin with a diamine is analyzed, taking into account the possibility of simultaneous etherification. A kinetic scheme is derived and fitted to experimental results for the reaction of commercial bisphenol A diglycidyl ether (BADGE) with diaminodiphenyl sulfone (DDS). Total reaction heat, vitrification curve, and reactivity ratio of secondary to primary amine hydrogens are experimentally characterized. It is shown that the etherification reaction is significant at T > 150°C, at intermediate and high reaction extents when the primary amine has been sufficiently depleted.  相似文献   
20.
Electrospun fibrous substrates mimicking extracellular matrices can be prepared by electrospinning, yielding aligned fibrous matrices as internal fillers to manufacture artificial nerves. Gelatin aligned nano-fibers were prepared by electrospinning after tuning the collector rotation speed. The effect of alignment on cell adhesion and proliferation was tested in vitro using primary cultures, the Schwann cell line, RT4-D6P2T, and the sensory neuron-like cell line, 50B11. Cell adhesion and proliferation were assessed by quantifying at several time-points. Aligned nano-fibers reduced adhesion and proliferation rate compared with random fibers. Schwann cell morphology and organization were investigated by immunostaining of the cytoskeleton. Cells were elongated with their longitudinal body parallel to the aligned fibers. B5011 neuron-like cells were aligned and had parallel axon growth when cultured on the aligned gelatin fibers. The data show that the alignment of electrospun gelatin fibers can modulate Schwann cells and axon organization in vitro, suggesting that this substrate shows promise as an internal filler for the design of artificial nerves for peripheral nerve reconstruction.  相似文献   
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