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991.
M.J. Kim S. Ajimura K. Aoki A. Banu H. Bhang T. Fukuda O. Hashimoto J.I. Hwang S. Kameoka B.H. Kang E.H. Kim J.H. Kim T. Maruta Y. Miura Y. Miyake T. Nagae M. Nakamura S.N. Nakamura H. Noumi S. Okada Y. Okayasu H. Outa H. Park P.K. Saha Y. Sato M. Sekimoto S. Shin T. Takahashi H. Tamura K. Tanida A. Toyoda K. Tsukada T. Watanabe H.J. Yim 《Physics letters. [Part B]》2006
992.
We define 〈q, r〉-linear arithmetical functions attached to the 〈q, r〉-number systems and give a necessary and sufficient condition for their generating power series to be algebraically independent
over
\Bbb C(z){\Bbb C}(z)
. We also deduce algebraic independence of the functions values at a nonzero algebraic number in the circle of convergence. 相似文献
993.
K. Okada 《Nuclear Physics B - Proceedings Supplements》2001,100(1-3)
The DONUT experiment has analyzed a sample of 203 neutrino interactions recorded in nuclear emulsion targets. Two decay search methods has done for long and short flight tau decay. Evidence of four tau neutrino interactions with an estimated background of 0.41 events and one with background of 0.22 events. 相似文献
994.
We construct new non-separable splines and we apply the spline sampling approximation to the computation of numerical solutions of evolution equations. The non-separable splines are basis functions which give a fine sampling approximation which enables us to compute numerical solutions by means of the method of lines combined with the Galerkin method. To demonstrate our approach we compute numerical solutions of the Burgers equation and the Kadomtsev–Petviashvili equation. 相似文献
995.
Z. Kobayashi T. Kuzumaki T. Okada T. Sekiguchi Y. Shiota 《Acta Mathematica Hungarica》2008,121(1-2):45-71
We define a probability measure which has Markov property on the unit interval, compute a higher order partial derivative of its distribution function about the parameter. As application, we obtain explicit formulas of a digital sum of the block of the binary number. 相似文献
996.
Soichi Okada 《Journal of Algebraic Combinatorics》2006,23(1):43-69
An alternating sign matrix is a square matrix with entries 1, 0 and −1 such that the sum of the entries in each row and each
column is equal to 1 and the nonzero entries alternate in sign along each row and each column. To some of the symmetry classes
of alternating sign matrices and their variations, G. Kuperberg associate square ice models with appropriate boundary conditions,
and give determinant and Pfaffian formulae for the partition functions. In this paper, we utilize several determinant and
Pfaffian identities to evaluate Kuperberg's determinants and Pfaffians, and express the round partition functions in terms
of irreducible characters of classical groups. In particular, we settle a conjecture on the number of vertically and horizontally
symmetric alternating sign matrices (VHSASMs).
Dedicated to the memory of David Robbins. 相似文献
997.
998.
999.
Wavelength switchings of a Fabry-Perot semiconductor laser are experimentally demonstrated by applying externally optical input pulses detuned from a cavity-resonant wavelength of the semiconductor laser with a constant injection current. The wavelength region of optical switching ranges from less than 0.1 nm to several nm over gain spectrum, being locked to the wavelength of optical inputs. These behaviors are based on multistability and multi-split branches in the optical output versus detuned optical input characteristics, caused by the carrier-induced refractive index change accompanied by optical injections. The experimental results are believed to be useful for wavelength division multiplexing and exchange in optical communication. 相似文献
1000.
Mathias Hoehn-Berlage Thomas Tolxdorff Kurt Bockhorst Yoshikazu Okada Ralf-Ingo Ernestus 《Magnetic resonance imaging》1992,10(6)
Experimental gliomas (F98) were inoculated in cat brain for the systematic study of their in vivo T2 relaxation time behavior. With a CPMG multi-echo imaging sequence, a train of 16 echoes was evaluated to obtain the transverse relaxation time and the magnetization M(0) at time t = 0. The magnetization decay curves were analyzed for biexponentiality. All tissues showed monoexponential T2, only that of the ventricular fluid and part of the vital tumor tissue were biexponential. Based on these NMR relaxation parameters the tissues were characterized, their correct assignment being assured by comparison with histological slices. T2 of normal grey and white matter was 74 ± 6 and 72 ± 6 msec, respectively. These two tissue types were distinguished through M(0) which for white matter was only 0.88 of the intensity of grey matter in full agreement with water content, determined from tissue specimens. At the time of maximal tumor growth and edema spread a tissue differentiation was possible in NMR relaxation parameter images. Separation of the three tissue groups of normal tissue, tumor and edema was based on T2 with T2(normal) < T2(tumor) < T2(edema). Using M(0) as a second parameter the differentiation was supported, in particular between white matter and tumor or edema. Animals were studied at 1–4 wk after tumor implantation to study tumor development. The magnetization M(0) of both tumor and peritumoral edema went through a maximum between the second and third week of tumor growth. T2 of edema was maximal at the same time with 133 ± 4 msec, while the relaxation time of tumor continued to increase during the whole growth period, reaching values of 114 ± 12 msec at the fourth week. Thus, a complete characterization of pathological tissues with NMR relaxometry must include a detailed study of the developmental changes of these tissues to assure correct experimental conditions for the goal of optimal contrast between normal and pathological regions in the NMR images. 相似文献