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41.
Samuel Clement Bradford 《Colloid and polymer science》1922,30(6):364-367
Ohne Zusammenfassung 相似文献
42.
Kristiane M. Van Lierde Bart Vinck Sofia De Ley Gregory Clement Paul Van Cauwenberge 《Journal of voice》2005,19(4):511-518
The main purpose of this study was to determine the vocal quality characteristics among the 45 monozygotic cotwins (MT). As the performance of the voice is related to several genetically determined anatomical and physiological factors, the authors hypothesized that the vocal characteristics and the overall vocal quality by means of the Dysphonia Severity Index (DSI) will be identical in MT. An additional objective of this study was to determine whether sex and age influence vocal similarities in MT and to compare the voice characteristics of MT with the normative data of unrelated peers. As more environmental factors influence the aging of the voice, age-related differences were expected. No sex-related differences were expected. Subjective and objective assessment techniques determined the vocal quality. No significant differences were obtained, and most comparisons resulted in significant correlation coefficients. For the acoustic parameters jitter and shimmer only, no significant correlation coefficients could be obtained. It is clear that the perceptual voice characteristics, the laryngeal aerodynamic measurements of maximum phonation time (MPT), the vocal performances, and the overall vocal quality by means of the DSI are similar in MT. These vocal characteristics are not influenced either by the subjects' age or sex and are situated within the normative range of unrelated peers. To what extent other aspects (environment, anxiety, tension, etc) might play a role in the acoustical dimensions regarding frequency and amplitude perturbation, which were in the normal range, is a subject of further research. 相似文献
43.
44.
The 01+ and 21+ parentage expansion of excited states in 139Ba, 141Ce and 145Sm has been determined via the analysis of the elastic and inelastic scattering of polarized protons in the energy region of their analog resonances. The extracted spectroscopic information indicates that present unified model calculations give a considerable overestimate of the strength of characteristic configurations in the weak coupling structure. 相似文献
45.
46.
Methods are devised to calculate the continuum strength of neutron valence orbits starting with an empirical optical-model potential. Allowance is made for the fact that the bound-state and real optical-model potentials have a common nonlocal origin. Direct calculations are made for the orbits of the contribution from the elastic-scattering chann also of the total continuum strength using a spectral representation. As predicted by McKellar and also by an improved perturbation model given here, most of the continuum strength lies in inelastic and rearrangement channels. When combined with 5% missing strength from the NN potential core, the estimated total continuum strength is ?12–15% of the single-particle sum rule, which is compatible with other deductions from experimental data. 相似文献
47.
In connection with the problem of finding the best projections of k-dimensional spaces embedded in n-dimensional spaces Hermann König asked: Given m∈ and n∈, are there n×n matrices C=(cij), i, j=1,…,n, such that cii=m for all i, |cij|=1 for i≠j, and C2=(m2+n?1)In? König was especially interested in symmetric C, and we find some families of matrices satisfying this condition. We also find some families of matrices satisfying the less restrictive condition CCT=(m2+n?1)In. 相似文献
48.
G. Clement 《Nuclear Physics B》1976,114(3):437-448
A family of Lagrangian models of two scalar fields in (2 + 1) dimensions is studied. All their localized static classical solutions are obtained, and interpreted as representing systems of extended particles. The models are generalized by taking into account general-relativistic gravirational coupling, for which case the general static solutions are also obtained explicitly. 相似文献
49.
Clement W.H. Lam 《Discrete Mathematics》1983,43(1):65-78
A matrix C of order n is orthogonal if CCT=dI. In this paper, we restrict the study to orthogonal matrices with a constant m > 1 on the diagonal and ±1's off the diagonal. It is observed that all skew symmetric orthogonal matrices of this type are constructed from skew symmetric Hadamard matrices and vice versa. Some simple necessary conditions for the existence of non-skew orthogonal matrices are derived. Two basic construction techniques for non-skew orthogonal matrices are given. Several families of non-skew orthogonal matrices are constructed by applying the basic techniques to well-known combinatorial objects like balanced incomplete block designs. It is also shown that if m is even and n=0 (mod 4), then an orthogonal matrix must be skew symmetric. The structure of a non-skew orthogonal matrix in the special case of m odd,n=2 (mod 4) and m?1/6n is also studied in detail. Finally, a list of cases with n?50 is given where the existence of non-skew orthogonal matrices are unknown. 相似文献
50.