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91.
Measurements of synchrotron radiation emitted by 30-MeV runaway electrons in the TEXTOR-94 tokamak show that the runaway population decays after switching on neutral beam injection (NBI). The decay starts only with a significant delay, which decreases with increasing NBI heating power. This delay provides direct evidence of the energy dependence of runaway confinement, which is expected if magnetic modes govern the loss of runaways. Application of the theory by Mynick and Strachan [Phys. Fluids 24, 695 (1981)] yields estimates for the "mode width" (delta) of magnetic perturbations: delta<0.5 cm in Ohmic discharges, increasing to delta = 4.4 cm for 0. 6 MW NBI. 相似文献
92.
P. Mason N. Marginean G. Montagnoli S. Beghini F. Scarlassara E. Farnea C. A. Ur A. Meroni A. M. Stefanini L. Corradi E. Fioretto I. V. Pokrovskiy B. Guiot A. Gadea J. J. Valiente-Dobón F. Della Vedova R. Orlandi E. Sahin D. R. Napoli L. Berti N. Toniolo S. Szilner M. Trotta M. Romoli M. La Commara D. Pierroutsakou M. Sandoli G. Pollarolo G. Benzoni 《The European physical journal. Special topics》2007,150(1):359-361
PRISMA is a magnetic
spectrometer installed at Laboratori Nazionali di Legnaro (Italy)
and designed for A=100–200, E=5–10 MeV-per-nucleon beams, and for
possible use with the proposed radioactive beam facility SPES. The
foremost features of the instrument are presented, along with the
outline of two data analyses exemplifying the effectiveness of
PRISMA-CLARA in studies of reaction
dynamics. 相似文献
93.
94.
95.
Jonathan W. D. Mason 《Complexity》2013,18(3):28-37
The theoretical base for consciousness, in particular, an explanation of how consciousness is defined by the brain, has long been sought by science. We propose a partial theory of consciousness as relations defined by typical data. The theory is based on the idea that a brain state on its own is almost meaningless but in the context of the typical brain states, defined by the brain's structure, a particular brain state is highly structured by relations. The proposed theory can be applied and tested both theoretically and experimentally. Precisely how typical data determines relations is fully established using discrete mathematics. © 2012 Wiley Periodicals, Inc. Complexity, 2012 相似文献
96.
97.
We consider a class of kernel estimators [^(t)]n,h\hat{\tau}_{n,h} of the tail index of a Pareto-type distribution, which generalizes and includes the classical Hill estimator [^(a)]n,k\hat{a}_{n,k}. It is well-known that [^(a)]n,k\hat{a}_{n,k} is a consistent estimator of the tail index if and only if k→ ∞ and k/n→0. Under suitable assumptions on the kernel, [^(t)] n,h\hat{\tau} _{n,h} is consistent whenever the bandwidth is taken to be a sequence of non-random numbers satisfying h
n
→0 and nh
n
→ ∞. We extend this result and prove the consistency uniformly over a certain range of bandwidths. This permits the treatment
of estimators of the tail index based upon data-dependent bandwidths, which are often used in practice. In the process, we
establish a uniform in bandwidth result for kernel-type regression estimators with a fixed design, which will likely be of
separate interest. 相似文献
98.
99.
A series of di-, tri-, and tetra-tetrazoloalkanes were synthesized from the corresponding nitrile and sodium azide. These were alkylated to give hydroxy terminated chains for possible use as high energy oligomers. 相似文献
100.