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Th. Heins 《e & i Elektrotechnik und Informationstechnik》2003,120(11):400-401
An enterprise is not just a tall shiny building or a collection of facilities. Rather, it is the sum of individuals collectively engaged in a common pursuit. From an information and communications perspective, this realization changes everything. By looking at the enterprise as a boundary-less collection of individuals who sometimes work in an office, sometimes at home, and sometimes on the road, we need new communications concepts designed to work with and enhance our complex home and work lives. 相似文献
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D. Dietrich ÖVE H. Reiter Th. Sauter H. -J. Schweinzer 《e & i Elektrotechnik und Informationstechnik》1997,114(5):225-230
The past decade may be regarded as the phase of the fundamental developments in fieldbus systems that were based on the OSI model. Today we are entering a second stage. It is the objective of this issue to present the current state and where the further developments will lead to. This introductory article is intended to give an overview on the subject. 相似文献
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A. J. Kalkman H. P. M. Pellemans T. O. Klaassen W. Th. Wenckebach 《Journal of Infrared, Millimeter and Terahertz Waves》1996,17(3):569-577
The low temperature lifetime of electrons excited in the 2p?1 donor level of n-GaAs has been studied in a far-infrared pump-probe experiment. The measurement has been carried out using a pulsed far-infrared molecular gas laser working at a wavelength of 292µm, with the sample in a magnetic field of 5.1 T, resonant with the 1so?2p?1 transition. Two FIR pulses are sliced from one FIR-laser pulse by means of optical switching techniques using two Q-switched Nd:YAG lasers. The first pulse is used to saturate the transition, while the second pulse probes the return of the population in the excited state towards thermal equilibrium as a function of the time delay after the excitation pulse. The value of 350±50 ns found for the lifetime falls in line with CW saturation results on materials with other doping concentrations. 相似文献
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Following two years operation of the 100 kW grid-connected installation N13 near Domat/Ems, Switzerland, considerable data are available. The yield of the installation was calculated on the basis of long-term meteorological data and of the Meteonorm model. The findings show a close correlation between the forecast and the measured yields. With 100% availability of the inverter in 1991, the performance of the installation rose from 59% in 1990 to 79% in 1991. With standardized analysis of the data, the performance of the grid-connected installation N13 can be compared with other grid-connected installations irrespective of size and location. 相似文献
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This paper presents a selection of results of a comprehensive quantitative, research literature-based study of Dutch energy research. The primary goal of this paper is to provide an overview of what bibliometric data from ISI and non-ISI databases may offer to describe the state of affairs in a scientific field. It illustrates the added value of combining bibliometric indicators of publication output, international visibility, international co-operation, and interdisciplinarity in a study of nuclear energy research in the 1980's when its budget decreased dramatically. 相似文献