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911.
912.
The characterization of the dynamic performances of a manipulator is important both to compare different manipulators and to improve the dynamic performances of a manipulator during the design stage. In a previous paper the concepts of swiftness and of dynamic isotropy were used to characterize some dynamic performances of 3-dof manipulators. This paper analyzes the usefulness of these concepts for three-dof planar manipulators and shows that the concept of swiftness is still significant, whereas the concept of dynamic isotropy has no practical interest. Moreover, it introduces three new dynamic properties that are useful in the design of a 3-dof planar manipulator. Finally, it proposes some indices that measure both the swiftness and the three new dynamic properties and shows how to use them, both for evaluating the dynamic performances of a given 3-dof planar manipulator and for improving the dynamic performances during its design. 相似文献
913.
We suggest a simple definition of the topological charge density Q(x) in the lattice Yang-Mills theory and evaluate A≡∝d4x〈Q(x)Q(0)〉 in SU(2) by Monte Carlo simulation. The “data” interpolate well between the strong and weak coupling expansions, which we compute to order g?12 and g6, respectively. After subtraction of the perturbative tail, our points exhibit the expected asymptotic freedom behaviour giving , K being the SU(2) quarkless string tension. Although a larger value for would be preferable, we are led to conclude (at least tentatively) that the UA(1) problem of QCD is indeed solved perturbatively in the quark loop expansion. 相似文献
914.
915.
M. Carlotti G. Di Lonardo G. Galloni A. Trombetti 《Journal of Molecular Spectroscopy》1980,84(1):155-161
The ir absorption of gaseous HNSO, DNSO and H15NSO is recorded in the range 300–4100 cm?1 at medium resolution. Besides the fundamental vibrations, overtones and combination bands are measured and assigned. From these data, combined with the ir absorptions of four more isotopic species of thionylimide, and with the centrifugal distortion constants of HNSO and DNSO, a harmonic force field, with 11 constants was derived. 相似文献
916.
917.
F.W. Büsser L. Camilleri L. Di Lella G.B. Pope A.M. Smith B.J. Blumenfeld S.N. White A.F. Rothenberg S.L. Segler M.J. Tannenbaum M. Banner J.B. Chèze H. Kasha J.P. Pansart G. Smadja J. Teiger H. Zaccone A. Zylberstejn 《Physics letters. [Part B]》1976,61(3):309-312
Transverse momentum distributions of , and Ko, produced in pp collisions at x = 0, have obtained at the CERN ISR. The Ko yield is in agreement with published K+, K? results, obtained at this centre-of-mass energy (√s≈44 GeV). The results on production obtained in this experiment are compared with results obtained at lower centre-of-mass energies. 相似文献
918.
919.
P. Minguzzi M. Tonelli A. Carrozzi A. Di Lieto 《Journal of Molecular Spectroscopy》1982,96(2):294-305
Laser Stark spectroscopy of the R(5, K) transitions in the ν2 band of ammonia was carried out using coincidences with the 9-μm band CO2 laser lines. We observed 22 Doppler-free resonances by using an optoacoustic detector and a Lamb-dip stabilized CO2 laser. A simultaneous analysis of sa, aa, and ss lines yields zero-field transition frequencies with an absolute accuracy of 1 ~ 2 MHz. 相似文献
920.
The 6.2 keV γ-rays of 181Ta have been used to study the hyperfine interaction of 181Ta in the trigonal prismatic charge density wave material 2H-TaSe2. Using a region of interest drive and an unstrained single crystal sample, we are able to resolve the splitting between the nuclear transition and . Our experimental linewidth is that of the Ta metal. 相似文献