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231.
Spectral Analysis as a Tool for Financial Policy: An Analysis of the Short-End of the British Term Structure 总被引:1,自引:0,他引:1
In this paper, we show how to derive the spectra and cross-spectra of economic time series from an underlying econometric or VAR model. This allows us to conduct a proper frequency analysis evaluation of economic and financial variables on a reduced sample of data, without it being ruled out by the large sample requirements of direct spectral estimation. We show, in particular, how this can be done for time-varying models and time-varying spectra. We use our techniques to show how the behaviour of British interest rates changed during and following the ERM crisis of 1992/3. 相似文献
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Preis K. Bardi I. Biro O. Magele C. Vrisk G. Richter K.R. 《IEEE transactions on magnetics》1992,28(2):1056-1059
Several finite-element formulations of three-dimensional magnetostatic fields are reviewed. Both nodal and edge elements are considered. The aim is to suggest remedies to some shortcomings of widely used methods. Various formulations are compared based on results for Problem No. 13 of the TEAM Workshops, a nonlinear magnetostatic problem involving thin iron plates 相似文献
235.
Nonoperative management of forearm fractures in children has a good outcome in over 90% of all cases. In our own series (n = 102) there were only six children (6.1%) with significant limitation (> 25 degrees) of forearm rotation. In these cases two out of four (50%) were located in the proximal third but only two out of 68 in the distal third. Indications for operative stabilization are the following: compound fractures, fractures associated with vessel and nerve injuries, joint fractures, dislocated fractures of the middle and proximal third, and Monteggia/Galeazzi injuries. As implants intramedullary devices are preferred. Twenty children were managed with elastic IM rods between 1994 and 1995 at our institution. At final follow-up all had a free ROM and a maximal axial malalignment of less than 5 degrees. In the region of the distal forearm K-wires are useful. Plates play a dominant role for corrections and nonunions; external skeletal stabilization is indicated for temporary fixation in compound fractures. 相似文献
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Ekkehard Richter 《化学工程与技术》1990,13(1):101-112
The BF-Uhde-Mitsui Process uses active coke for SO2- and NOx-removal from flue gases in the temperature range between 100 and 190 °C, Experimental methods of thermal regeneration were applied to the evaluation of the state of the adsorbent after use in flue gas cleaning and of the parameters for disrober design. A reaction model was derived from experiments carried out in differential and back-mix reactors. The parameters were evaluated by adaptation of the model to the adsorption spectra. The model was successfully applied to the regeneration of active coke in a fluidized bed reactor. 相似文献
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