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991.
Conlon P.J. Tong Y.P. French P.M.W. Taylor J.R. Shestakov A.V. 《Electronics letters》1994,30(9):709-710
Sub-100 fs pulse generation from a Kerr lens modelocked Cr4+ :YAG laser has been demonstrated for the first time, yielding femtosecond pulses tunable from 1.49 to 1.56 μm with pulses as short as 90 fs obtained at 1.53 μm 相似文献
992.
The ARM-Uchet computerized system is considered, which is intended for accounting, planning, and monitoring for metrological support to an organization and has been implemented on an IBM PC AT. Schemes are given for the basic modes of operation and for the software suites, as well as the database structure.Translated from Izmeritel'naya Tekhnika, No. 7, pp. 70–71, July, 1994. 相似文献
993.
Concentrators are used to interface and combine together low speed communication channels onto higher speed transmission links to alleviate transmission costs. They are also used to construct more powerful switching fabrics such as permutation and broadcast networks. Using an adaptive binary sorting network model, this paper constructs new concentrators and superconcentrators. Unlike the previously reported concentrators and superconcentrators, these new constructions are fast, and ran easily be implemented using simple switching devices. More specifically, for n inputs, they can be constructed with O(n lg lg n) constant fanin bit-level multiplexers and demultiplexers, and can be routed in O(lg2 n) bit-level time 相似文献
994.
In a two-channel transmission system, the signal-to-noise ratio (SNR) at the receiver can in general be different for the channels. Normally, performance will be dominated by the channel with the worst SNR, but it is possible to do much better. The general scheme proposed provides optimum performance when the SNR varies between the channels and/or when the interference is correlated, without varying the transmitted power for each channel. Simplified schemes attain nearly optimum performance under certain channel conditions 相似文献
995.
Canavan A. G. M.; Springelmeyer R.; Diener H.-C.; H?mberg V. 《Canadian Metallurgical Quarterly》1994,108(3):475
Eight patients with lesions restricted to the cerebellum were compared with a total of 25 age-matched controls on an reaction time (RT) task allowing the recording of simple and choice RTs as well as RTs to abstract visual patterns signifying the particular movement to be performed. In all conditions the actual movements required (either a left or a right button press) remained the same, but the cognitive requirements of the task varied. In the abstract patterns condition, the significance of the various patterns with regard to the required movement had to be learned by the Ss. The patients with cerebellar lesions were particularly impaired in this condition. It is concluded that the cerebellum is involved not just in the timing of movements but also in the decision process as to which movement should be performed under particular circumstances. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Simoes A.S. Silva M.M. Anunciada A.V. 《Industrial Electronics, IEEE Transactions on》1994,41(2):251-255
A boost type converter is described that is suitable for low-voltage DC-supply of fluorescent lamps. It has inherent lamp current limitation (ballast action) and provides the high voltage pulses and electrode heating that are required for igniting the lamp. The proposed circuit is applicable in automotive, emergency, and portable light sources.<> 相似文献
997.
Zolper J.C. Shenvin M.E. Baca A.G. Shul R.J. Klem J.F. Hietala V.M. 《Electron Device Letters, IEEE》1994,15(12):493-495
C ion implantation has been employed, for the first time, to form the buried p-layer in GaAs, self-aligned, ion implanted JFETs. Comparable DC performance was seen for JFETs with C or Mg implants; however, C-backside JFETs showed superior high-frequency performance. High dose C-backside devices had a ft of 28.3 GHz and a fmax of 43.2 GHz for a 0.5 μm gate length that were 28% and 46% higher, respectively, than comparable Mg-implanted JFETs. This enhancement is a result of the lower Cgs in the C-backside device resulting from he inherently low activation of the implanted C below the channel while the C still effectively compensated the tail of the Si-channel implant. This approach relaxes the trade-off between optimizing the DC and the AC performance for the buried p-implant in GaAs JFETs and MESFET's 相似文献
998.
A recently completed single-site study has yielded information about how Internet traffic will evolve, as new users discover the Internet and existing users find new ways to incorporate the Internet into their work patterns. The author reviews existing statistics and studies of network growth, which show that network traffic generally grows exponentially with time, at least until the network carrying capacity is reached. He then describes how he captured and reduced the data used in this study. The following points are also addressed: the overall growth in the site's wide-area traffic; the appearance of periodic traffic; the growth in network use by individual computers or users; and the changing geographic profile of the traffic. The implications and limitations of the results are also summarizes 相似文献
999.
In this article we propose efficient scan path and BIST schemes for RAMs. Tools for automatic generation of these schemes have been implemented. They reduce the design effort and thus allow the designer to select the more appropriate scheme with respect to various constraints. 相似文献
1000.
Signature analyzers are very efficient output response compactors for BIST design. The only limitation of signature analysis is the fault coverage reduction (aliasing) due to the information loss inherent to any data compaction. In this article, in order to increase the effectiveness of ROM BIST, we take advantage from the simplicity of the error patterns generated by ROMs and we show that aliasing free signature analysis can be achieved in ROM BIST.This work was performed when the author was on leave from Minsk Radio Engineering Institute, Computer Department, Belorus. 相似文献