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991.
We prove that any non-autonomous KdV-flow with local non-trivial conserved densities of arbitrarily high order is essentially autonomous. 相似文献
992.
Javier Gamboa Félix Javier Jiménez-Jiménez Alberto Nieto Jose Montojo Miguel Ortí-Pareja José Antonio Molina Esteban García-Albea Ignacio Cobeta 《Journal of voice》1997,11(3):314-320
To quantify several acoustic features of the voice in patients withParkinson's disease (PD), 41 patients and 28 age and sex-matched controls were studied. PD severity was assessed with the Unified PD Rating Scale (UPDRS) and the Hoehn and Yahr staging. The Computerized Speech Lab 4300 program (Kay Elemetrics) was used. Two seconds of a sustained /a/ and a sentence were captured with a microphone and laryngograph equipment. Measures included fundamental frequency (FO), frequency perturbation (fitter), intensity perturbation (shimmer), and harmonic/noise ratio (H/N) of the vowel /a/, and frequency and intensity variability of a sentence, phonational range, dynamic range at the natural frequency, maximum phonational time and s/z ratio. All subjects underwent indirect laryngoscopy and/or laryngeal fibroscopy. When compared with controls, PD patients showed higher jitter, lower H/N ratio, lower frequency and intensity variability of the sentence, and lower phonational range and reported a higher frequency of the presence of low voice-intensity, monopitch, voice arrests, and struggle. These features seem to be unaffected by the duration and severity of the disease. 相似文献
993.
The protonation of NADH-like dihydropyridines and cyclic enol ethers generates reactive cationic intermediates, which interact with isocyanides to afford α-carbamoylated heterocycles after an aqueous quenching, in Ugi and Passerini-type reactions, thus broadening the scope of these multicomponent processes. 相似文献
994.
Brahim Hnich Zeynep Kiziltan Ian Miguel Toby Walsh 《Annals of Operations Research》2004,130(1-4):19-39
We study a balanced academic curriculum problem and an industrial steel mill slab design problem. These problems can be modelled in different ways, using both Integer Linear Programming (ILP) and Constraint Programming (CP) techniques. We consider the utility of each model. We also propose integrating the models to create hybrids that benefit from the complementary strengths of each model. Experimental results show that hybridization significantly increases the domain pruning and decreases the run-time on many instances. Furthermore, a CP/ILP hybrid model gives a more robust performance in the face of varying instance data. 相似文献
995.
The transformation of the organopalladium compound (3) into the corresponding deuteriated, chlorinated, or oxidized derivatives (7), (8), or (9), (11), and (12) respectively. is described. The palladation of compound (9) takes place regioselectively leading to the palladated system (13), which is transformed into the difunctionalised oximes (15) and (16). The palladation of -2,2-dimethyl and 2,2,6,6-tetramethyl-cyclohexanone oxime leads to the corresponding organopalladium compounds (17) and (27), which through deuteriation or oxidation affords the expected products (21) and (31), or (22), (23), (24), and (32), respectively. The second palladation of the compound (22) takes place on the remaining methyl group yielding the organopalladium derivative (26). Finally, -lupanone oxime is palladated selectively in the 23-position leading to the organopalladium compound (38); the transformation of this compound into its 23-deuterio and 23-acetoxy- derivatives (41) and (42), respectively is also described. The stereochemistry in the palladatlon of lupanone oxime is deduced from NOE studies at 500 MHz. 相似文献
996.
By means of the world-function, an approximate formula for the relative deformation tensor of an elastic continuum in a space-time opf finite curvature is obtained. The coordinate displacements are supposed to be small with respect to the characteristic measure of the geodesic joining an arbitrary point of that continuum and a fixed point of the space-time. The formula contains all the terms up to the third order of approximation with respect to this geodesic measure, which is the basis of the approximation. 相似文献
997.
J. M. Gambi A. San Miguel F. Vicente 《International Journal of Theoretical Physics》1988,27(1):107-130
The equations of motion in fourth approximation for gravitational bodies are used to obtain orbital equations, first integrals, differential equations for the corresponding trajectories, and fourth-order contributions to the orbital motions in stationary weak gravitational fields. 相似文献
998.
999.
M. Miguel Cervantes F. Marcelino Barboza Motomichi Inoue 《Journal of Russian Laser Research》1991,12(5):447-451
A large optical nonlinearity of thermal origin has been observed in acetone solutions of a series of tetraphenylporphin, TPPH2, MnTPP(CH3CO2
–), FeTTPCI-, CoTPP, NiTPP, and CuTPP. The nonlinear Kerr coefficient is sensitively dependent on the nature of central metals in the compounds. The Mn compound exhibits the largest coefficient, 6 × 10–5 esu, for 514 nm laser wavelength. The use of prophins offers increased flexibility in the preparation of different Kerr media.Presented at the International Workshop on Squeezed and Correlated States in Quantum Optics, Moscow, December 3–7, 1990. 相似文献
1000.