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991.
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995.
Two techniques for the design and fast search of a vector quantiser codebook are proposed. These classify speech data vectors according to (i) the sign and (ii) the slope between successive samples. With both techniques the performance obtained is superior to that obtained from a conventional gain/shape vector quantiser and comparable to that of a full search vector quantiser. A major attraction of both approaches is that they significantly reduce the number of computations required for the codebook search. 相似文献
996.
D G Kindack A MacIntosh M Lebelle G Carignan S Sved 《Food Additives & Contaminants》1991,8(6):737-748
During surveillance of hog carcasses from Manitoba for antibiotic residues by the Health of Animals Laboratory, Agriculture Canada, Saskatoon, an unknown substance was found which produced tetracycline-like results with the methods used. This same substance was found in an implicated swine feed premix. Using various HPLC systems and columns, UV spectroscopy, reverse-phase TLC, and mass spectrometry, the substance was isolated from the feed premix, and identified as lumichrome, a photodegradation product of riboflavin. Traces of the same substance were found in riboflavin standard. Analysis of swine kidney, previously found to contain the unknown, showed the same substance was present at a level of about 1 ppm. 相似文献
997.
A. O. Skomorokhov V. N. Kutinsky M. T. Slepov 《Pattern Recognition and Image Analysis》2006,16(1):85-88
The paper describes a few modifications of the classification tree construction algorithm that have proved to be useful for
solving tasks of noise spectra processing with reference to NPP diagnostics.
The article was translated by the authors. 相似文献
998.
The effect of coherency loss on the development of precipitate size distribution under cascade-producing irradiation is considered. The nucleation of coherent precipitates, their growth followed by coherency loss and cascade-induced dissolution of large incoherent precipitates can occur simultaneously resulting in formation of a quasi-stationary size distribution of semicoherent precipitates. To describe this process we consider co-evolution of a mixed population of coherent, semicoherent and incoherent precipitates. Mathematically, the problem is formulated as a set of discrete rate equations of nucleation kinetics (the Master equation approach) which is also used for later stages of evolution. To solve the corresponding large set of equations (typically, more than 105 equations) an efficient numerical method is developed. The simulation results obtained for material parameters and irradiation conditions typical for nuclear reactors show that the coherency loss affects considerably evolution of the precipitate population. Under certain irradiation conditions, both in solution-annealed alloys and in aged ones, the mean precipitate size and the number density during prolonged irradiation tend to steady state values, whereas the size distribution function of large precipitates narrows. The width of the quasi-stationary size distribution is controlled by cascade parameters. It was found that the asymptotic quasi-stationary state of the precipitate population may depend on initial state of the alloy. 相似文献
999.
I. Ya. Braslavskii A. V. Kostylev D. V. Mezeusheva 《Russian Electrical Engineering》2007,78(11):603-606
The use of prognostic control methods in the digital systems controlling asynchronous electric drives are considered. The methodology for synthesizing predictors on the basis of neural networks is explained. An example of the synthesis of a numeral predictor for a closed control loop is considered. 相似文献
1000.
Bilateral control of teleoperators with time delay 总被引:5,自引:0,他引:5
A control law for teleoperators is presented which overcomes the instability caused by time delay. By using passivity and scattering theory, a criterion is developed which shows why existing bilateral control systems are unstable for certain environments, and why the proposed bilateral control law is stable for any environment and any time delay. The control law has been implemented on a single-axis force-reflecting hand controller, and preliminary results are shown. To keep the presentation clear, a single-degree-of-freedom (DOF) linear time-invariant (LTI) teleoperator system is discussed. Nevertheless, results can be extended, without loss of generality, to an n -DOF nonlinear teleoperation system 相似文献