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111.
A simple method based on Sagnac interferometric spectroscopy (SIS) is applied for frequency stabilization of diode lasers. Sagnac interferometric spectra of rubidium vapor are investigated both theoretically and experimentally. The interference signal at the output of the Sagnac interferometer displays a sharp dispersion feature near the atomic resonance. This dispersion curve is used as the feedback error signal to stabilize the laser frequency. Linewidth of a diode laser is stabilized down to 1 MHz by this modulation-free method. 相似文献
112.
Shalom Eliahou Rafael H. Villarreal 《Proceedings of the American Mathematical Society》2002,130(2):345-351
Let be a toric set in the affine space . Given a set of binomials in the toric ideal of , we give a criterion for deciding the equality rad( ) = . This criterion extends to arbitrary dimension, and to arbitrary fields, an earlier result which concerned only monomial curves over an algebraically closed field of characteristic zero.
113.
This paper is concerned with algorithms for computing in the divisor class group of a nonsingular plane curve of the form which has only one point at infinity. Divisors are represented as ideals, and an ideal reduction algorithm based on lattice reduction is given. We obtain a unique representative for each divisor class and the algorithms for addition and reduction of divisors run in polynomial time. An algorithm is also given for solving the discrete logarithm problem when the curve is defined over a finite field.
114.
Analogy is used to treat the system of non-interacting integrate-and-fire neurons as an ideal Fermi gas. It allows to obtain the nonlinear gain curve in the form of sigmoid in agreement with biological findings. As the by-product the gain-threshold mechanism in neurons is presented. Surprisingly enough, this is in agreement with new biological findings, too. Besides, the application of this mechanism to the dynamics of neurons leads to the non-monotone transfer function. 相似文献
115.
In this paper we present an algorithm for recursively generating orthogonal bivariate polynomials on a discrete set S 2. For this purpose we employ commuting pairs of real symmetric matrices H, K
n×n
to obtain, in a certain sense, a two dimensional Hermitian Lanczos method. The resulting algorithm relies on a recurrence having a slowly growing length. Practical implementation issues an applications are considered. The method can be generalized to compute orthogonal polynomials depending on an arbitrary number of variables. 相似文献
116.
Emil Žagar 《BIT Numerical Mathematics》2002,42(3):670-688
In this paper the problem of G
2 continuous interpolation of curves in
d
by polynomial splines of degree n is studied. The interpolation of the data points and two tangent directions at the boundary is considered. The case n = r + 2 = d, where r is the number of interior points interpolated by each segment of the spline curve, is studied in detail. It is shown that the problem is uniquely solvable asymptotically, e., when the data points are sampled regularly and sufficiently dense, and lie on a regular, convex parametric curve in
d
. In this case the optimal approximation order is also determined. 相似文献
117.
Atsushi Moriwaki 《Compositio Mathematica》2002,132(2):191-228
Let M
g
be the moduli space of smooth curves of genus g 3, and M¯
g
the Deligne-Mumford compactification in terms of stable curves. Let M¯
g
[1] be an open set of M¯
g
consisting of stable curves of genus g with one node at most. In this paper, we determine the necessary and sufficient condition to guarantee that a
-divisor D on M¯
g
is nef over M¯
g
[1], that is, (D · C) 0 for all irreducible curves C on M¯
g
with C M¯
g
[1] . 相似文献
118.
119.
Z. Xiancheng N. Zhaodong X. Yan Z. Yuanqin Z. Honglin 《Journal of Thermal Analysis and Calorimetry》1999,58(2):279-285
The power-time curves of two species of bacteria, Vibro metschnikovii, Vibro bollisae were determined calorimetrically by using a 2277 bioactivity monitor. The power-time curve equation of bacterial growth in the log phase can be expressed as
. A self-function recursion equation, fi=b1fi+1+b2fi+2, was obtained through the perfect non-linear function
. A linear equation, i/i+1=b1+b2i+2/i+1, was obtained by using the self-function recursion equation. The rate constants of bacterial growth k1, the time constant of the calorimeter k, the generation times G, and the pre-exponential factors A were obtained from the power—time curve equations.Power—time curve equations of bacterial growth in the log phase are expressed for V.metschnikovii as =1.05(e0.0228t–e–0.0175t), and for V. bollisae as =1.58(e0.0278t–e–0.0170t).This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
120.
Some previous results of the author towards a classification of homogeneous metric continua are improved. The disjoint arcs property is fully revealed in this context. In particular, closed -manifolds, , are characterized as those homogeneous continua which do not have the disjoint arcs property.