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991.
In the treatment of the risk-sensitive control problem, it is known that the criterion function may not have a finite value.
The risk parameter cannot be arbitrary. Conditions have been presented by the authors in previous papers to guarantee the
no breakdown. In the present article, we present a framework in which the conditions can be greatly relaxed.
Accepted 7 January 1999. Online publication 5 October, 2000. 相似文献
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995.
Atsushi Taguchi Norihiko Hayazawa Kentaro Furusawa Hidekazu Ishitobi Satoshi Kawata 《Journal of Raman spectroscopy : JRS》2009,40(9):1324-1330
We report for the first time the tip‐enhancement of resonance Raman scattering using deep ultraviolet (DUV) excitation wavelength. The tip‐enhancement was successfully demonstrated with an aluminum‐coated silicon tip that acts as a plasmonic material in DUV wavelengths. Both the crystal violet and adenine molecules, which were used as test samples, show electronic resonance at the 266‐nm excitation used in the experiments. With results demonstrated here, molecular analysis and imaging with nanoscale spatial resolution in DUV resonance Raman spectroscopy can be realized using the tip‐enhancement effect. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
996.
H. Shiraga S. Fujioka M. Nakai T. Watari H. Nakamura Y. Arikawa H. Hosoda T. Nagai M. Koga H. Kikuchi Y. Ishii T. Sogo K. Shigemori H. Nishimura Z. Zhang M. Tanabe S. Ohira Y. Fujii T. Namimoto Y. Sakawa H. Azechi 《High Energy Density Physics》2012,8(3):227-230
Implosion and heating experiments at the Institute of Laser Engineering, Osaka University on Fast Ignition (FI) targets for the FIREX-1 project have been performed with Gekko-XII laser for implosions and LFEX laser for heating. We tried to reduce the prepulse level in the LFEX laser system and have improved the plasma diagnostics to observe the plasma in the harsh hard X-ray environment. A plastic (CD) shell target, 7-μm thick and 500 μm in diameter with a hollow gold cone was used in this experiment to guide the short-pulse laser at the time of the maximum compression. The shell target was imploded with 9 or 12 beams of Gekko-XII laser (527 nm) with energy of 300 J/beam in a 1.5 ns pulse. Two of the four LFEX laser (1053 nm) beams were injected into the inside bottom of the cone with an energy up to 0.7 kJ/beam in a 1.5 ps pulse at the time around the maximum implosion. We have observed neutron enhancement up to 3.5 × 107 with total heating energy of 300 J, which is higher than the yield obtained in the previous experiment in 2002 [R. Kodama et al. Nature 418, 933 (2002)]. We found the estimated heating efficiency is at a level of 10–20%. Fuel heating to 5 keV is expected when the full output of LFEX is used. 相似文献
997.
By measuring the angular-oscillations behavior of the heat capacity with respect to the applied field direction, one can detect the details of the gap structure. We introduce the Kramer-Pesch approximation as a new method to analyze the field-angle-dependent experiments, which improves the previous Doppler-shift technique. We show that the Fermi-surface anisotropy is an indispensable factor for identifying the superconducting gap symmetry. 相似文献
998.
Fatemeh Abrishamian Shinichi Nagai Shinya Sato Masaaki Imai 《Optical and Quantum Electronics》2008,40(9):665-676
Spectral response of acoustically induced microbending through thin optical fiber is discussed from mode-coupling of core
and cladding modes. The thin fiber is analyzed in three-layered structure (core-cladding-air) to gain insights into acousto-optic
modulation. We explained the dependence of core and/or cladding diameters on acoustic source parameters from numerical calculations.
According to the calculations, we successfully fabricated all-optical tunable filter using this thin fiber that yields an
efficient mode-coupling at flexural wave frequencies less than 1MHz. To increase the acousto-optic effect, we used a specially
designed thin optical fiber (80 μm of cladding diameter) in the section where flexural wave is produced, and spliced both
ends of the thin fiber to the tapered 125 μm fibers. The frequency and voltage tuning of fabricated filter is also confirmed
by changing the driven frequency and applied voltage of the PZT, respectively. This result suggests a possibility of fiber-optic
device application as all-optical tunable filter at 1.55 μm. 相似文献
999.
Akira Nagai Ryo Nishimura Yohei Hattori Eri Hatano Ayako Fujimoto Masakazu Morimoto Nobuhiro Yasuda Kenji Kamada Hikaru Sotome Hiroshi Miyasaka Satoshi Yokojima Shinichiro Nakamura Kingo Uchida 《Chemical science》2021,12(34):11585
Here, we present single crystalline capsules of a photoresponsive molecule produced by simple recrystallization from organic solutions without direct human processing. During the crystal growth process, a movie was taken of the capsule taking in the organic solution. The capsules responded rapidly (<1 s) to the UV light stimuli and released the captured solution or solute. In principle, they can take in any substance dissolved in organic solvents, and their size can be controlled. Moreover, the capsule can be broken by multi-photon excitation using a near-infrared laser within the biological window. Furthermore, because the molecular packing in the crystal is unidirectional, the response can be controlled by the polarization of the light. This study shows the new potential of photoresponsive molecules.A novel diarylethene formed “crystalline capsules” containing liquid inclusions, and chemicals trapped in the capsules were released by photoinduced breaking. Operations by multiphoton and linear polarized light were demonstrated. 相似文献
1000.
The diarylprolinol‐mediated asymmetric direct cross‐aldol reaction of α,β‐unsaturated aldehyde as an electrophilic aldehyde was developed. The reaction becomes accelerated by an acid when a carbonyl group is introduced at the γ‐position of the α,β‐unsaturated aldehyde. Synthetically useful γ,δ‐unsaturated β‐hydroxy aldehydes were obtained with high anti‐selectivity and excellent enantioselectivity. 相似文献