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991.
Summary We study the integration theory for general integral metrics when restricted to upper integrals q, finding improvements in the relation between the classes of the q-integrable and the ql-integrable functions. We give new results and notions which lead to the desirable characterizations of q-integrable functions as ql-integrable f with q(|f|) < ∞, and of ql-integrable functions via the integrability of their upper truncations, under natural conditions which are fulfilled in most finitely additive integration theories.  相似文献   
992.
993.
Off-the-shell anomalous factors of the two-body Coulomb transition matrices appear in the integral form of the Faddeev second-order nuclear-electronic amplitude, for proton-hydrogen charge transfer scattering in a typical nlmnlm′ transition. A symmetric-impulse approximation (SIA) is applied to eliminate these factors and an induction method is proposed to analytically calculate the remaining integrals. The nuclear-electronic amplitude is derived for the general case, and for totally symmetric collisions, in terms of generalized hypergeometric functions of two variables, F 4, and of one variable, 3 F 2, respectively. The angular distribution of the second-order nuclear-electronic charge transfer amplitude shows the Thomas mechanism as a peak or a hump for symmetric and asymmetric collisions. There also exists a peak in the forward angular distribution of the second-order nuclear-electronic amplitude, which partly cancels the kinematic peak in the angular distribution of the charge transfer differential cross sections.  相似文献   
994.
995.
996.
The systematics of hyperfine magnetic fields at sp impurities on the Z-sites in Co based Heusler alloys are investigated. New TDPAC measurements of Cd hyperfine fields are reported.  相似文献   
997.
In AIDS control, physicians have a growing need to use pragmatically useful and interpretable tools in their daily medical taking care of patients. Semi-Markov process seems to be well adapted to model the evolution of HIV-1 infected patients. In this study, we introduce and define a non homogeneous semi-Markov (NHSM) model in continuous time. Then the problem of finding the equations that describe the biological evolution of patient is studied and the interval transition probabilities are computed. A parametric approach is used and the maximum likelihood estimators of the process are given. A Monte Carlo algorithm is presented for realizing non homogeneous semi-Markov trajectories. As results, interval transition probabilities are computed for distinct times and follow-up has an impact on the evolution of patients.   相似文献   
998.
Digital holographic shape measurements using femtosecond laser pulses are reported. For contouring of very fast moving objects, the simultaneous generation of at least two spectrally separated ultrashort pulses is required. To deliver this particular spectral signature at high pulse energies, a chirped-pulse Ti:sapphire laser amplifier was modified to emit two spectrally separated pulses with energies above 1 μJ each. The wavelength separation of these pulses was adjustable within the 50 nm gain bandwidth, cutting out two distinct wavelength peaks by a variable double-slit assembly in a prism sequence. A Michelson-type interferometer was employed to perform the two-wavelength contouring. The phases of the holograms and the phase differences are calculated numerically, which allow us to deduce the contour lines of the topology of the object. The suitability of the light source for digital holography is demonstrated with contouring of stationary objects and the potential for high-speed applications is indicated. PACS 42.40.-i; 42.60.By  相似文献   
999.
We use the spectral ballistic imaging technique to measure the impulse response of a Fabry–Pérot etalon with less than 0.2 ps temporal resolution. The results show excellent agreement with the theoretical predictions and negligible noise. Comparison to the Kramers–Kronig method along with its limitations is also presented. PACS 42.65.Re; 07.60.Ly; 42.30.Kq  相似文献   
1000.
A high efficiency launcher of quasi-optical (QO) mode converters for high power gyrotrons have been designed and tested. A helical cut launcher radiates the RF power via its straight cut onto the first phase correcting mirror. The launchers have been optimized for the TE31.8 mode at 170 GHz and TE22.6 mode at 110 GHz by numerically optimizing a launcher surface. The helical cut of the launcher has been optimized by taking the taper angle into account. Further more, the amplitude of the surface perturbation have been optimized for improved focusing in order to reduce the diffraction losses at the helical cut. Low power measurement shows a good agreement with the design. High efficiency characteristics of the design have also been calculated on the assumption of frequency downshift due to the thermal expansion of the cavity and stepwise frequency tuning by changing the operating mode. Besides, the possibility of high efficiency launcher for higher mode is discussed, and these results give the prospect to high efficiency long pulse gyrotrons.  相似文献   
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