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41.
Tamada Tsutomu Ueda Yu Kido Ayumu Yoneyama Masami Takeuchi Mitsuru Sanai Hiroyasu Ono Kentaro Yamamoto Akira Sone Teruki 《Magma (New York, N.Y.)》2022,35(4):549-556
Magnetic Resonance Materials in Physics, Biology and Medicine - Image quality (IQ) of diffusion-weighted imaging (DWI) with single-shot echo-planar imaging (ssEPI) suffers from low signal-to-noise... 相似文献
42.
Xia Cao Wang Dong F. Ono Takahito Itoh Toshihiro Esashi Masayoshi 《Microsystem Technologies》2022,28(11):2443-2453
Microsystem Technologies - In this paper, a system of magnetically coupled oscillators consisting of a Π-shaped horizontal cantilever and a rectangular vertical cantilever with a frequency... 相似文献
43.
An efficient critical control system design is proposed in this paper. The key idea is to decompose the design problem into two simpler design steps by the technique used in the classical loop transfer recovery method (LTR). The disturbance cancellation integral controller is used as a basic controller. Since the standard loop transfer recovery method cannot be applied to the disturbance cancellation controller, the nonstandard version recently found is used for the decomposition. Exogenous inputs with constraints both on the amplitude and rate of change are considered. The majorant approach is taken to obtain the analytical sufficient matching conditions. A numerical design example is presented to illustrate the effectiveness of the proposed design. 相似文献
44.
45.
46.
A quantum-inspired evolutionary algorithm (QEA) is proposed as a stochastic algorithm to perform combinatorial optimization
problems. The QEA is evolutionary computation that uses quantum bits and superposition states in quantum computation. Although
the QEA is a coarse-grained parallel algorithm, it involves many parameters that must be adjusted manually. This paper proposes
a new method, named pair swap, which exchanges each best solution information between two individuals instead of migration
in the QEA. Experimental results show that our proposed method is a simpler algorithm and can find a high quality solution
in the 0-1 knapsack problem.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
47.
Spinal-Formed Context-Free Tree Grammars 总被引:1,自引:0,他引:1
In this paper we introduce a restricted model of context-free tree grammars called spine grammars, and study their formal
properties including considerably simple normal forms. Recent research on natural languages has suggested that formalisms
for natural languages need to generate a slightly larger class of languages than context-free grammars, and for that reason
tree adjoining grammars have been widely studied relating them to natural languages. It is shown that the class of string
languages generated by spine grammars coincides with that of tree adjoining grammars. We also introduce acceptors called linear
pushdown tree automata, and show that linear pushdown tree automata accept exactly the class of tree languages generated by
spine grammars. Linear pushdown tree automata are obtained from pushdown tree automata with a restriction on duplicability
for the pushdown stacks.
Received May 29, 1998, and in revised form April 27, 1999, and in final form May 10, 1999. 相似文献
48.
49.
The paper places five different problems (thek-pebble game problem, two problems aboutk finite automata, the reachability problem for Petri nets withk tokens, and the teachability problem for graphs whose k-dimensional edge sets are described by Cartesian products ofk factors) into the hierarchyNL
k
of problems solvable by nondeterministic Turing machines ink-log2
n space (and binary tape alphabet, to avoid tape speed-up). The results, when combined with the conjecture thatNL
i
contains problems that requireO(n
k
) deterministic time, show that these problems, while inP for every fixed value ofk, have polynomial deterministic time complexities with the degree of the polynomial growing linearly with the parameterk, and hence are, in this sense, gradually intractable. 相似文献
50.
Yoshimasa A. Ono Jun'ichiro Hara Katsuhiko Nagai Kiyoshi Kawamura 《Journal of Low Temperature Physics》1977,27(3-4):513-536
The shear viscosity (T) in the Balian-Werthamer (BW) state of superfluid
3
He is calculated variationally throughout the region 0t 1(t=T/T
c) from the transport equation for Bogoliubov quasiparticles. Coherence factors are treated exactly in the calculation of the collision integral. The numerical result for
=s= s(T)/n(Tc) agree very well with experiment in the range 0.8t1.0. Analytic expressions
= 0.577 (1–1.0008t) and
=1–(23/64) [=(T)/k
B
T] are obtained in the low-temperature region and in the vicinity ofT
c, respectively. From the numerical analysis it is shown that the latter equation is valid only in the temperature range 0.9997t1.0.Supported by the Research Institute for Fundamental Physics, Kyoto University. 相似文献