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11.
Ferdinand P. Ferragu O. Lechien J.L. Lescop B. Magne S. Marty V. Rougeault S. Kotrotsios G. Neuman V. Depeursinge Y. Michel J.B. Van Uffelen M. Varelas D. Berthou H. Pierre G. Renouf C. Jarret B. Verbandt Y. Stevens W. Voet M.R.H. Toscano D. 《Lightwave Technology, Journal of》1995,13(7):1303-1313
Recent developments of stability control in mines, essentially based on Ge-doped fiber Bragg gratings (FBG) are reported including results about the different aspects of the system: accurate characterizations of FBG, sensor network topology and multiplexing method, user interface design and sensor packaging 相似文献
12.
Lennart Ljung Pierre Priouret 《International Journal of Adaptive Control and Signal Processing》1991,5(6):395-403
The purpose of this paper is to extend recent results of Ljung and Priouret to a more general class of regressors. 相似文献
13.
In this paper nucleation of superconductivity in films in investigated numerically for all temperatures. Recent predictions of magnetically enhanced superconductivity, even above the critical temperature, are not confirmed. In a limiting case also the surface critical fieldH
c3 was obtained for all temperatures.Dedicated to Professor L. Tewordt on the occasion of his 65th birthday. 相似文献
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We propose a new formulation for the Linke turbidity coefficient with the objective of removing its dependence upon solar geometry. In the process, we also develop two new simple clear sky models for global and direct normal irradiance. 相似文献
17.
The authors present the design and the development of integrated microwave filters using suspended substrate microstrip, a technology that provides many advantages. Through quasi-static approximation the propagation structure has been treated using integral equations solved with the method of moments. Thanks to this tool of analysis and to an accurate synthesis method, a series of bandpass filters have been designed and manufactured. The results presented validate the accuracy of our design method. 相似文献
18.
The hypothesis that orienting visual attention is an important component of visual curve tracing was investigated. Ss examined a visual display and decided as quickly as possible whether 2 dots were on the same or different curves. The rate of tracing was determined by measuring the effects of curve distance on response time. Attention was directed to a curve by momentarily presenting it at a higher luminance. Directing attention to a curve that had 2 dots on it resulted in faster tracing rates with large benefits in overall response time. Directing attention to a distractor curve resulted in slower tracing rates and sizable costs in overall response times. Two alternative nonattentional explanations (eye movements and visible persistence) were examined and rejected. The role of attention in curve tracing is discussed in terms of the selective nature of curve tracing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Michel Dorbon Pierre Henri Bigeard Jacques Denis Christian Bernasconi 《Petroleum Science and Technology》1992,10(8):1313-1341
As established by several previous works, nitrogen compounds play a prominent role in the evolution of middle distillates containing cracked components, particularly regarding sediment formation and color evolution.
In a first part, this paper describes and compares stability properties of fuel blends using both an accelerated ageing method at 120°C (248°F ) and long term storage methods at 43°C(110°F) -ASTM 0 4625 - and at ambient temperature. Effectiveness of stabilizing additives is also evaluated. In mixtures containing LCOs, insoluble products are formed progressively during ageings, more or less rapidly according to the chemical constitution of the mixtures.
Then, it reports the complete identification of nitrogen compounds using gas chromatography equipped with a selective nitrogen detector and mass spectrometry showing that in light cycle oils, alkyl indoles and carbazoles are the main families.
Evolution of these compounds was followed kinetically during ageings in absence and presence of additives and alkyl indoles appeared as the moat evolutionary.
It appeared that some additives avoided evolutions of alkyl indoles without preventing sediment formation and color evolution. Oxidation mechanism involving nitrogen compounds should not be the only one to explain the storage evolutions of middle distillates.
Hydrotreatment converts all the alkyl indoles of LCO and prevents coloration end deposits in the storage of the mixtures of steaight-run distillates and LCOs. 相似文献
In a first part, this paper describes and compares stability properties of fuel blends using both an accelerated ageing method at 120°C (248°F ) and long term storage methods at 43°C(110°F) -ASTM 0 4625 - and at ambient temperature. Effectiveness of stabilizing additives is also evaluated. In mixtures containing LCOs, insoluble products are formed progressively during ageings, more or less rapidly according to the chemical constitution of the mixtures.
Then, it reports the complete identification of nitrogen compounds using gas chromatography equipped with a selective nitrogen detector and mass spectrometry showing that in light cycle oils, alkyl indoles and carbazoles are the main families.
Evolution of these compounds was followed kinetically during ageings in absence and presence of additives and alkyl indoles appeared as the moat evolutionary.
It appeared that some additives avoided evolutions of alkyl indoles without preventing sediment formation and color evolution. Oxidation mechanism involving nitrogen compounds should not be the only one to explain the storage evolutions of middle distillates.
Hydrotreatment converts all the alkyl indoles of LCO and prevents coloration end deposits in the storage of the mixtures of steaight-run distillates and LCOs. 相似文献
20.
André Girard Pierre Dominique Lansard Bernard Liau Anne Marie Mongeon Jean Luc Thibault 《电信纪事》1991,46(5-6):335-350
Classical hierarchical routing in telephone networks is extended to a wider class called out-of-chain routing in such a way that some useful properties of hierarchical routing are retained. This new routing pattern offers more potential paths than the fixed hierarchical one and can be introduced as a dynamic routing where the fixed alternate sequences change at some predetermined instants during the day. The effect of this new routing pattern on the network performances is examined. The main topic of this paper is to present heuristic methods used to optimise such routings in large networks. We show on artificial networks that the throughput of a given network can be significantly improved by suitable routing choices. We demonstrate that the integration of routing changes within a multihour dimensioning process is possible but the lack of realistic data does not permit at this time to quantify the value of routing optimization on real networks. 相似文献