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91.
Tetsuya Yuasa Shinji Tanosaki Yoshiaki Sasaki Michiaki Takagi Akira Ishikawa Hiroshi Taniguchi Balasigamani Devaraj Takao Akatsuka 《Analytical sciences》2002,18(12):1329-1333
The coherent detection imaging (CDI) method uses the optical heterodyne detection technique. CW and single frequency lasers having long coherence lengths are used to exploit the maximum advantages of heterodyne detection, such as high directionality, selectivity and sensitivity. The CDI method based on optical heterodyne detection enables selective filtering of the directional coherence-retaining emergent photons, which leads to image reconstruction from projections, similar to X-ray computed tomography (CT). So far we have demonstrated the advantages and capabilities of the measurement technique for transillumination optical computed tomography in biomedicine. Here, we investigate the fundamental imaging properties of CDI method, such as its high directionality and quantitativeness, with preliminary physical phantom experiments. The results show that the CDI method satisfies the requirements for CT reconstruction under the first order approximation, and enables quantitative measurements in the sense that the relationship between estimated and actual concentration retains a satisfactory linearity. 相似文献
92.
A successive quadratic programming algorithm with global and superlinear convergence properties 总被引:6,自引:0,他引:6
Masao Fukushima 《Mathematical Programming》1986,35(3):253-264
This paper presents a successive quadratic programming algorithm for solving general nonlinear programming problems. In order to avoid the Maratos effect, direction-finding subproblems are derived by modifying the second-order approximations to both objective and constraint functions of the problem. We prove that the algorithm possesses global and superlinear convergence properties.This work was supported in part by a Scientific Research Grant-in-Aid from the Ministry of Education, Science and Culture, Japan. 相似文献
93.
Kenji Yoshii Yasuhiro Yoneda Ignace Jarrige Tatsuo Fukuda Yasuo Nishihata Chikashi Suzuki Yoshiaki Ito Takahito Terashima Shinzo Yoshikado Sei Fukushima 《Journal of Physics and Chemistry of Solids》2014
We have studied the electronic properties of the ferroelectric barium titanate BaTiO3 using two complementary bulk-sensitive spectroscopic probes, resonant X-ray emission spectroscopy (RXES) and X-ray absorption spectroscopy in the partial fluorescence mode (PFY-XAS) at the Ba-L3 and Ti-K absorption edges. Contrary to a previous study, we found no fine structure in the pre-edge area of the PFY-XAS spectrum at the Ba-L3 edge, and no temperature-induced spectral change was observed between room temperature and 150 °C. This result is not supportive of the possible presence of the displacement around Ba2+ at the Curie temperature. RXES spectra were measured at the Ti-K edge for BaTiO3, along with SrTiO3 and La-doped metallic SrTiO3. The photon energy of the emission peak is found to be nearly constant throughout the absorption edge for all three compounds. We deduce the Ti 3d states to have a delocalized character, in contrast with the Ba 5d states, a property which is consistent with the proposed scenario of the formation of electric dipoles in BaTiO3. 相似文献
94.
In this paper, we propose a general smoothing Broyden-like quasi-Newton method for solving a class of nonsmooth equations. Under appropriate conditions, the proposed method converges to a solution of the equation globally and superlinearly. In particular, the proposed method provides the possibility of developing a quasi-Newton method that enjoys superlinear convergence even if strict complementarity fails to hold. We pay particular attention to semismooth equations arising from nonlinear complementarity problems, mixed complementarity problems and variational inequality problems. We show that under certain conditions, the related methods based on the perturbed Fischer–Burmeister function, Chen–Harker–Kanzow–Smale smoothing function and the Gabriel–Moré class of smoothing functions converge globally and superlinearly. 相似文献
95.
Yoshiaki Shimura Kazuhiko Hashimoto Chiaki Yamanaka Daisuke Setojima 《Journal of polymer science. Part A, Polymer chemistry》2001,39(22):3893-3901
New styryl‐type water‐insoluble and methacryloyl‐type water‐soluble monomers, N‐(p‐vinylbenzyl)‐1,2‐O‐isopropylidene‐6‐D ‐glucofuranuronamide and N‐(2‐methacryloylamino)ethyl‐1,2‐O‐isopropylidene‐6‐D ‐glucofuranuronamide, were synthesized from the most common acidic saccharide, D ‐glucuronic acid. Their radical homopolymerizations and copolymerizations with styrene and acrylamide were tried under various conditions. The isopropylidene groups in the resulting polymers were removed in a mixture of trifluoroacetic acid and water (2/1 v/v) to give the corresponding polymers with many pendant D ‐glucopyranuronyl groups with reactive reducing groups. The pendant reducing ends may be useful as potential binding sites under a hydrophilic atmosphere. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3893–3901, 2001 相似文献
96.
Luís M. Fernandes Joaquim J. Júdice Hanif D. Sherali Masao Fukushima 《Journal of Global Optimization》2014,59(2-3):307-326
In this paper, a parametric algorithm is introduced for computing all eigenvalues for two Eigenvalue Complementarity Problems discussed in the literature. The algorithm searches a finite number of nested intervals \([\bar{l}, \bar{u}]\) in such a way that, in each iteration, either an eigenvalue is computed in \([\bar{l}, \bar{u}]\) or a certificate of nonexistence of an eigenvalue in \([\bar{l}, \bar{u}]\) is provided. A hybrid method that combines an enumerative method [1] and a semi-smooth algorithm [2] is discussed for dealing with the Eigenvalue Complementarity Problem over an interval \([\bar{l}, \bar{u}]\) . Computational experience is presented to illustrate the efficacy and efficiency of the proposed techniques. 相似文献
97.
T. Tatsumi T. Fukushima K. Imada M. Takayanagi 《Journal of Macromolecular Science: Physics》2013,52(3):459-483
The effect of heat treatment of trans-1,4-polybutadiene single crystals prepared from dilute benzene solution was studied by dilatometry, X-ray diffraction, and dynamic viscoelastic measurement. The crystal transformation temperature of the single crystal is 55.5[ddot]C, 20[ddot]C lower than that of the bulk crystallized sample. After heat treatment of the single crystal above 55.5[ddot]C, their crystal transformation temperature increases to 69.5[ddot]C. At the same time, thickening of the lamellae suddenly occurs and the viscoelastic primary absorption observed in the single crystal mat disappears. It is suggested that this means that the amorphous region attached to the single crystal rapidly crystallized above this temperature, in particular the loose loops attached to the end surface of the crystal are dragged into the crystalline phase to form tight loops as a result of the sliding diffusion of molecules along their axes. This is accompanied by the sudden thickening of the lamellae at the crystal transformation temperature. These observations confirmed more thoroughly our previous prediction that the single crystal of trans-1, 4-polybutadiene, as formed, contains loose loops. The thickening phenomena and the change in the crystal transformation temperature of the trans-1,4-polybutadiene single crystal by heat treatment are also discussed from the thermodynamic viewpoint. 相似文献
98.
Yoshiaki Yasuno Shuichi Makita Takashi Endo Gouki Aoki Masahide Itoh Toyohiko Yatagai 《Optical and Quantum Electronics》2005,37(13-15):1157-1163
High speed complex full-range Fourier domain optical coherence tomography (FD-OCT) is demonstrated. This FD-OCT requires only a single A-scan for each single transversal position for full-range Fourier domain optical coherence tomography. The Fourier transform method is applied along the direction of the B-scan to reconstruct complex spectra, and the complex spectra compose a full-range OCT image. 相似文献
99.