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91.
M. H. Thoma H. Höfner M. Kretschmer S. Ratynskaia G. E. Morfill A. Usachev A. Zobnin O. Petrov V. Fortov 《Microgravity science and technology》2006,18(3-4):47-50
PK-4 is an experiment designed to investigate complex plasmas (low-temperature plasmas containing microparticles, e.g. dust grains) in a combined dc/rf discharge under microgravity conditions on board of the International Space Station. Within the 35th and 36th ESA parabolic flight campaigns first experiments under microgravity conditions in a specially designed experiment set-up have been performed. The particle flow inside the tube, the appearance of dust waves, and lane formation in interpenetrating particle clouds have been observed. 相似文献
92.
A. N. Tugov V. F. Moskvichev G. A. Ryabov V. I. Ugnachev A. N. Smirnov Yu. V. Petrov 《Thermal Engineering》2006,53(7):552-558
Using the results of activities on developing and adjusting the processes pertinent to thermal reprocessing of solid domestic wastes (SDWs), that were carried out by VTI specialists along with GUP Ekotekhprom specialists in 1999–2005, we selected operating conditions under which the power installations run in compliance with the requirements (adopted both in Russia and in the EU countries) imposed on the incineration of SDWs and purification of flue gases. It is indicated that ways are currently being considered of increasing the parameters of steam generated at SDW-fired power stations from the existing p = 1.2?1.4 MPa and t sup = 300?320°C to p = 4.0 MPa and t sup = 400°C to make the generation of electricity at them more efficient. Experience gained in this field by the boiler manufacturing plants in Russia is analyzed. 相似文献
93.
A. Nikolic Lj. Petrov Dj. Koruga S. Mihajlovic 《Fullerenes, Nanotubes and Carbon Nanostructures》2005,13(1):53-59
Magnetic behavior of C60 thin films in the Earth's magnetic field under polarization light influence is presented. Transformation of magnetic field for two fullerene thin films of different thickness is investigated. Two proton magnetometers were used for these measurements. Samples of 30 nm and 250 nm thickness illustrate a significant change of magnetic field intensity under the influence of polarization light, in range from 3.4 to 12.9 nT, for 200 measurement data per sample. 相似文献
94.
V. V. Petrov A. A. Kryuchin S. M. Shanoylo V. I. Sidorenko 《Cybernetics and Systems Analysis》2003,39(5):777-782
Potentialities of the methods of information processing, distribution, and storage are analyzed. Directions are defined in which optical information media characteristics can be improved. Possibility of using optical media for a long-term storage of digital information is considered. 相似文献
95.
Petrov S. I. Kaidash A. P. Krasovitskii D. M. Sokolov I. A. Pogorel’skii Yu. V. Chalyi V. P. Shkurko A. P. Stepanov M. V. Pavlenko M. V. Baranov D. A. 《Technical Physics Letters》2004,30(7):580-582
Technical Physics Letters - InGaN/GaN heterostructures have been grown by molecular beam epitaxy (MBE) using ammonia as a source of nitrogen. The influence of the growth temperature and rate on the... 相似文献
96.
Extraction of U(VI) from perchlorate solutions with diantipyrylmethane derivatives in chloroform and dichloroethane is studied. The composition of extractable complexes is [UO2L2](ClO4)2. The extraction constants are estimated. The maximal extractive power is shown by diantipyrylmethane in dichloroethane. Introduction of substituents at the methylene carbon of the extractant molecule makes the extraction worse. 相似文献
97.
98.
Stabilization of strict‐feedback nonlinear systems with input delay using closed‐loop predictors 下载免费PDF全文
Filippo Cacace Francesco Conte Alfredo Germani Pierdomenico Pepe 《国际强度与非线性控制杂志
》2016,26(16):3524-3540
》2016,26(16):3524-3540
In this paper, we consider the control problem of strict‐feedback nonlinear systems with time‐varying input and output delays. The approach is based on the usual observer/predictor/feedback approach, but the novelty is the use of the closed‐loop dynamics in the predictor. This approach allows to develop two designs, an instantaneous predictor and a delay differential equation‐based predictor, that both attain the same performance in terms of system trajectories and input signal as in the case with no delays. The design based on delay differential equations allows to build a cascade of predictors to deal with arbitrarily large delay bounds. The resulting controller is much simpler to implement than classical infinite‐dimensional predictors, and it is robust with respect to actuation and measurement disturbances. We illustrate the approach with an application to the control of a chaotic system with input delay. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
99.
P. Petrov 《Zeitschrift für Jagdwissenschaft》1972,18(2):66-76
Zusammenfassung Durch Rundfrage und ergänzende Untersuchungen wurde der gegenwärtige Bestand an Auerwild im südlichen Teil des Verbreitungsgebiets der Art ermittelt. Gegenwärtig leben in Bulgarien etwa 2600 Stück in fünf Vorkommen mit Schwerpunkten in den Rhodopen (70%) und im Rilagebirge (20%). Der zahlenmäßige Rückgang und das Verschwinden an den Rändern der Vorkommensgebiete wird für die letzten 50 Jahre dargestellt. Die Ursache für den Rückgang ist in der zunehmenden Nutzung der Wälder und in der Störung durch die wirtschaftliche Tätigkeit und den Verkehr zu suchen.
Summary By means of questionnaires and supplementary studies, the present conditions of Capercaillie in the southern part of its habitat was ascertained. Currently, about 2,600 birds are living in Bulgaria in five main areas, with concentrations in the Rhodope (70%) and in the Rila Moun-
Résumé Par voie d'enquête complétée par des recherches, l'effectif actuel de l'Urogalle est établi pour la partie méridionale de l'aire d'extension de l'espèce: quelque 2600 têtes d'Urogalle sont réparties en cinq stations, principalement dans les Rhodopes (70%) et dans le Mont Rila (20%). On fait état de la régression de l'espèce en périphérie de son aire de dispersion au cours des cinquante dernières années.Les causes de cette diminution sont à rechercher dans l'exploitation de plus en plus intensive des forêts, dans l'activité économique croissante et dans le développement des voies de communication.相似文献
100.
Alfredo Vaccaro Gianluca BontempiSouhaib Ben Taieb Domenico Villacci 《Electric Power Systems Research》2012,83(1):129-135
A massive deployment of wind energy in power systems is expected in the near future. However, a still open issue is how to integrate wind generators into existing electrical grids by limiting their side effects on network operations and control. In order to attain this objective, accurate short and medium-term wind speed forecasting is required.This paper discusses and compares a physical (white-box) model (namely a limited-area non hydrostatic model developed by the European consortium for small-scale modeling) with a family of local learning techniques (black-box) for short and medium term forecasting. Also, an original model integrating machine learning techniques with physical knowledge modeling (grey-box) is proposed.A set of experiments on real data collected from a set of meteorological sensors located in the south of Italy supports the methodological analysis and assesses the potential of the different forecasting approaches. 相似文献