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11.
Analysis of Spectral Reflectance Using Normalization Method from Endoscopic Spectroscopy System 总被引:2,自引:0,他引:2
Masao Sambongi Makoto Igarashi Takashi Obi Masahiro Yamaguchi Nagaaki Ohyama Masahiko Kobayashi Yasushi Sano Shigeaki Yoshida Kazuhiro Gono 《Optical Review》2002,9(6):238-243
Objective assessment of gastrointestinal mucosal color is extremely important in the endoscopic diagnosis of digestive tract disease. In this paper, we propose a method to clarify the spectral characteristics of gastric and colon cancer. A large number of spectral reflectance data of mucous membrane are measured by the endoscopic spectroscopy system (ESS) in the National Cancer Center Hospital East, Kashiwa, Japan and the Department of Internal Medicine, Self-Defense Force Center Hospital, Tokyo, Japan. We assume that early cancer appears primarily in the spectral data of short wavelength, because it is usually present in a superficial cell where short wavelength light is scattered more strongly than long wavelength light. To identify the features in the short wavelength components, the spectral reflectance was divided by the reflectance of a long wavelength. We investigated the possibility of distinguishing early cancer from normal spectral data through statistical analysis, employing the projection axis as the mean difference between them. Early cancer and normal spectral data were projected on the projection axis, and the Student’s T-test was applied to evaluate the mean of the distribution between these data. 相似文献
12.
13.
Kazuhiro Kurata Masataka Shibata Shigeru Sakamoto 《Applied Mathematics and Optimization》2004,50(3):259-278
Let $\Omega$ be a bounded domain in ${\bf R^n}$ with Lipschitz
boundary,
$\lambda >0,$ and $1\le p \le (n+2)/(n-2)$ if $n\ge 3$ and $1\le p< +\infty$
if $n=1,2$. Let $D$ be a measurable subset of $\Omega$ which belongs
to the class
$
{\cal C}_{\beta}=\{D\subset \Omega \quad | \quad |D|=\beta\}
$
for the prescribed $\beta\in (0, |\Omega|).$
For any $D\in{\cal C}_{\beta}$, it is well known that
there exists a unique
global minimizer $u\in H^1_0(\Omega)$, which we denote by
$u_D$, of the functional
\[\quad
J_{\Omega,D}(v)=\frac12\int_{\Omega}|\nabla v|^2\,
dx+\frac{\lambda}{p+1}\int_{\Omega}|v|^{p+1}\, dx
-\int_{\Omega}\chi_Dv\,dx
\]
on $H^1_0(\Omega)$.
We consider the optimization problem
$
E_{\beta,\Omega}=\inf_{D\in {\cal C}_{\beta}} J_D(u_D)
$
and say that
a subset $D^*\in {\cal C}_{\beta}$ which attains
$E_{\beta,\Omega}$
is an optimal configuration to this problem.
In this paper we show the existence, uniqueness
and non-uniqueness, and
symmetry-preserving and symmetry-breaking phenomena of the
optimal configuration $D^*$ to this
optimization problem in various settings. 相似文献
14.
Kazuhiro Yamamoto Haruhiko Ito Kouki Totsuka Tomohiro Sato 《Optics Communications》2006,265(2):692-695
We consider a new scheme of optically ionizing atoms with 10-nm-order spatial resolution. In this method, two-color near-field lights are generated on a narrow slit illuminated by two-color evanescent lights via total-internal reflection of two-wavelength light beams. In order to illustrate the feasibility, we first obtain the ionization cross section from two-step photionization of cold Rb atoms by two-color evanescent lights on a plane surface of a prism. Then, we numerically estimate the ionization efficiency as a function of the slit width using Bethe formula. The scheme is useful for detecting ground-state atoms under less perturbation by scattered light. 相似文献
15.
Yan Yin Otoo Yamada Shunsuke Hayashi Kazuhiro Tanaka Hidetoshi Kita Ken‐Ichi Okamoto 《Journal of polymer science. Part A, Polymer chemistry》2006,44(12):3751-3762
A series of branched/crosslinked sulfonated polyimide (B/C‐SPI) membranes were prepared and evaluated as proton‐conducting ionomers based on the new concept of in situ crosslinking from sulfonated polyimide (SPI) oligomers and triamine monomers. Chemical branching and crosslinking in SPI oligomers with 1,3,5‐tris(4‐aminophenoxy)benzene as a crosslinker gave the polymer membranes very good water stability and mechanical properties under an accelerated aging treatment in water at 130 °C, despite their high ion‐exchange capacity (2.2–2.6 mequiv g?1). The resulting polymer electrolytes displayed high proton conductivities of 0.2–0.3 S cm?1 at 120 °C in water and reasonably high conductivities of 0.02–0.03 S cm?1 at 50% relative humidity. In a single H2/O2 fuel‐cell system at 90 °C, they exhibited high fuel‐cell performances comparable to those of Nafion 112. The B/C‐SPI membranes also displayed good performances in a direct methanol fuel cell with methanol concentrations as high as 50 wt % that were superior to those of Nafion 112. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3751–3762, 2006 相似文献
16.
Hiroyuki Higuchi Kazuhiro Takatsu Tetsuo Otsubo Yoshiteru Sakata Soichi Misumi 《Tetrahedron letters》1982,23(6):671-672
A novel cage compound was obtained by irradiation of a quadruple-layered dithiacyclophane and showed thermally reverse reaction. 相似文献
17.
Influence of shell strength on shape transformation of micron-sized,monodisperse, hollow polymer particles 总被引:1,自引:0,他引:1
Micron-sized, monodisperse, non-spherical polymer particles with "rugby ball" and "red blood corpuscle"-like shapes were produced by seeded polymerization of the dispersion of (divinylbenzene/vinylbiphenyl/xylene)-swollen polystyrene particles prepared by utilizing the dynamic swelling method which the authors proposed in 1991. Their non-spherical shapes were based on buckling of the shell of the resultant hollow particles. In this article, the reversible shape transformation of the hollow composite polymer particle between spherical and such non-spherical shapes was studied in detail by controlling the shell strength. A part of the shell was buckled by external pressure which was caused by evaporation of xylene from the hollow when the shell had the tensile modulus below the critical value calculated from the pressure-buckling relationship of a spherical shell proposed by Uemura. The plasticization of the shell by a good solvent was one of key factors for the shape transformation. 相似文献
18.
Hideki Nishimori Masahiro Tatsumisago Tsutomu Minami 《Journal of Sol-Gel Science and Technology》1997,9(1):25-31
Monodispersed silica particles up to ca. 1.2 μm in diameter were prepared by hydrolysis of tetraethoxysilane in the presence
of sodium dodecyl sulfate (SDS). The particle size was increased with an increase of SDS added. The geometrical standard deviation
of the particles was decreased with an increase of SDS. In the earlier reaction stage, double spherical particles by the coalescence
of the particles were frequently observed when large amounts of SDS were added. Particle size was gradually increased after
the coalescence occurred and spherical particles were finally obtained. The results of Nielsen’s chronomal analysis suggest
that the polynuclear layer growth took place after the coalescence of the particles in the presence of larger amount of SDS. 相似文献
19.
The title racemate-to-conglomerate transformation which occurs in the solid state on heating or contact with MeOH vapour has been studied by IR and DTA spectral measurements, microscopic observation, and by X-ray structural and X-ray powder diffraction analysis. 相似文献
20.
Atsunori Matsuda Tatsuo Matoda Yoshinori Kotani Toshihiro Kogure Masahiro Tatsumisago Tsutomu Minami 《Journal of Sol-Gel Science and Technology》2003,26(1-3):517-521
Anatase nanocrystals were precipitated mainly at the surface of the silica-titania gel films with hot water treatment, whereas the addition of poly(ethylene glycol) (PEG) in the films led to the dispersion of anatase nanocrystals in the whole of the films after the treatment. Both films with and without PEG showed high photocatalytic activities for acetaldehyde, NO
x
and stearic acid in the gas-solid system, and for methylene blue and potassium iodide in the liquid-solid system. The addition of PEG improved the photocatalytic activities of the resultant films due to the smaller anatase crystallites and the porous film structure. The residual silica under-layer of the superficially anatase-precipitated films is expected to act as a protective one for an organic polymer substrate against the photocatalytic degradation. 相似文献