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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Carsey F.D. Argus S.A.D. Collins M.J. Holt B. Livingstone C.E. Tang C.L. 《Geoscience and Remote Sensing, IEEE Transactions on》1989,27(5):468-482
Ice observations, results, and conclusions are summarized for the March 1987 Labrador Ice Margin Experiment (LIMEX'87), an international oceanographic study conducted in the pack ice of the Grand Banks area off the coast of Newfoundland. Included are the ice extent, flow size and thickness, ice kinematics and rheology, ice microwave properties, oceanic properties under the ice, and penetration of swell into the ice 相似文献
982.
Yu. A. Brychkov A. P. Prudnikov 《Journal of Engineering Physics and Thermophysics》1987,52(6):725-728
One-dimensional Laplace transforms are given for some step functions.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 52, No. 6, pp. 999–1003, June, 1987. 相似文献
983.
S. O. Shiryaeva A. I. Grigor’ev V. A. Koromyslov A. S. Golovanov 《Technical Physics Letters》2002,28(1):41-43
A dispersion equation for the capillary oscillations of a charged drop of incompressible liquid possessing a finite electric
conductivity is derived with an allowance for the energy lost as a result of the electromagnetic wave emission. The magnitude
of the electromagnetic radiation losses of the oscillating drop linearly increases with the electric conductivity and the
surface mobility of charge carriers. 相似文献
984.
V. V. Skurat N. M. Shiryaeva N. K. Myshkina A. A. Gvozdev G. Z. Serebryanyi N. B. Golikova 《Journal of Engineering Physics and Thermophysics》2002,75(5):1200-1206
Unsatisfactory conditions of storage of decontamination waste (DW) in the storages formed in the territory of Belarus after the Chernobyl accident require the evaluation of the level of protection of the environment and population. The potential hazard of the decontamination waste burial grounds (DWBGs) has been evaluated based on the use of a generalized multichamber model that was verified by comparing the calculation results and the results obtained by the American (GW SCREEN) model. The characteristics of the 24 largest and most hazardous DWBGs are given and the evaluations of their safety are presented. The zones of influence of these storages, whose size varies from 100 to 330 m, have been determined. The reliability of the prediction evaluation of a possible hazardous radioactive contamination of water near the storages has been verified using the Dudichi DWBG as an example. 相似文献
985.
Bayne S.B. Tipton C.W. Griffin T. Scozzie C.J. Geil B. Agarwal A.K. Richmond J. 《Electron Device Letters, IEEE》2002,23(6):318-320
The high-temperature operation of a silicon carbide gate turn-off thyristor is evaluated for use in inductively loaded switching circuits. Compared to purely resistive load elements, inductive loads subject the switching device to higher internal power dissipation. The ability of silicon carbide components to operate at elevated temperatures and high power dissipations are important factors for their use in future power conversion/control systems. In this work, a maximum current density of 540 A/cm2 at 600 V was switched at a frequency of 2 kHz and at several case temperatures up to 150°C. The turn-off and turn-on characteristics of the thyristor are discussed 相似文献
986.
L A Geddes 《IEEE engineering in medicine and biology magazine》2002,21(6):152-153
There are several psychiatric illnesses that are difficult to treat with drugs. Among these are schizophrenia, manic depression, and profound depression; many of these may involve a tendency to suicide. In 1938 U. Cerletti conducted convulsive experiments on pigs using power-line current applied to electrodes at various sites. The effect of current duration was also investigated. As yet it is not known which areas in the brain are the optimum targets for the therapeutic use of cranially applied current to treat psychiatric illnesses, although the frontal lobes appear to be the best targets. 相似文献
987.
988.
Writing project reports is an important part of the engineering curriculum at Singapore universities. One important section of the formal report is the literature review. Most universities around the world provide guidelines on writing reviews, emphasizing that plagiarism is unethical. However, these guidelines do not offer explicit training on how to avoid plagiarism. In order to write academically acceptable reviews while avoiding copying from source materials, students face a major challenge and resort to employing various strategies to cope with the task. In this study, we examined the literature review sections of final year project reports to find out how engineering undergraduates in a Singapore university cope with writing reviews and to suggest ways in which they can extend their skills to improve their literature reviews. 相似文献
989.
990.