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991.
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
992.
Recently, differential geometric properties of embedded projective varieties have gained increasing interest. In this note, we consider plane algebraic curves equipped with the Fubini--Study metric from2 () and give an estimate for the diameter in terms of the degree, initiated in a paper by F. A. Bogomolov. 相似文献
993.
Yasunori Fujikoshi Takashi Kanda Megu Ohtaki 《Annals of the Institute of Statistical Mathematics》1999,51(4):707-721
This paper deals with some inferential problems under an extended growth curve model with several hierarchical within-individuals design matrices. The model includes the one whose mean structure consists of polynomial growth curves with different degrees. First we consider the case when the covariance matrix is unknown positive definite. We derive a LR test for examining the hierarchical structure for within individuals design matrices and a model selection criterion. Next we consider the case when a random coefficients covariance structure is assumed, under certain assumption of between-individual design matrices. Similar inferential problems are also considered. The dental measurement data (see, e.g., Potthoff and Roy (1964, Biometrika, 51, 313-326)) is reexamined, based on extended growth curve models. 相似文献
994.
The purpose of this paper is to provide a characterization result for the canonical basis of an arbitrary closure operator. This theorem strengthens the result of Burosch, Demetrovics and Katona, who propose a characterization of the generating system of a closure operator defined by the quasi-closed sets of the closure operator. 相似文献
995.
CHEN Hao 《数学年刊B辑(英文版)》1999,20(4):407-412
61.IntroductionSincethepoineeringworkofZariskil1o]therehavebeenmanypaperspublishedonthemodulinumberofplanecurvesingUlaritiesl5-9].TheproblemhowtocomputethemodulinumberattractsmWattentions[3'6-1o1.Asfarastheauthors'knowledgethemostgener-aJizedalgorithmistheworkof[3]whichdependsonthedivisiontheoremin[1,2].HerewegivealinearalgebraicproofoftheBriancon-Granger-Maisonobe,stheoremlwhichavoidstheDivisiontheorem.Sincethedivisiontheoremonlyholdsindimension2,itseemsquitehopefUlthattheproofherewil1beg… 相似文献
996.
拟线性椭圆型方程的非线性边值问题——Sobolev临界指数的情形 总被引:1,自引:0,他引:1
本文讨论一类具有Sobolev临界指数的拟线性椭圆型方程非线性边值问题的非平凡解的存在性,利用集中紧原理得到一个存在性结果。 相似文献
997.
拟合隐函数曲线的GNL法 总被引:5,自引:1,他引:4
朱珉仁 《高等学校计算数学学报》1999,21(3):269-276
1参数可线性化的曲线拟合问题假设我们已经获得n组独立观测值(xi,yi),其中是精确观测值,i=1,2,…,n,下同.现欲在最小二乘意义下,拟合非线性模型并假设观测点都分布在模型函数曲线附近.其中为连续可导函数g(y)的反函数,且在我们所研究的y变化范围内恒有g’(y)≠0,(j=1,2.....下同)为p(<n)个待定参数.(x)为区间X内p个线性无关的已知连续函数.随机变量,即为也就是要求求解残差平方和Q()的无条件极值问题其中参数向量,残差向量,而残差都是微量.对这类常见问题,有以下几种算法.… 相似文献
998.
The value of adjustable parameterC in the four-parameter potentialU(r) =D
e [(1 - exp[-b(r -r
e)])/(1 -C exp[-b(r -r
e)])]2 has been expressed in terms of molecular parameters and its significance has been brought out. The potential so constructed,
withC derived from the molecular parameters, has been applied to ten electronic states in addition to the states studied by Wei
Hua. Average mean deviation for these 25 states has been found to be 3.47 as compared to 6.93, 6.95 and 9.72 obtained from
Levine, Varshni and Morse potentials, respectively. Also Dunham’s method has been used to express rotation-vibration interaction
constant (αe) and anharmonicity constant (ωexe) in terms ofC and other molecular constants. These relations have been employed to determine these quantities for 37 electronic states.
For αe, the average mean deviation is 7.2% compared to 19.7% for Lippincott’s potential which is known to be the best to predict
these values. Average mean deviation for (ωexe) turns out to be 17.4% which is almost the same as found from Lippincott’s potential function. 相似文献
999.
The neutron response of electrochemically etched (ECE) CR-39 detectors is determined by the energy and angular dependence of the response to neutron-induced charged particles. This response has been measured for the example of protons with various initial energies and angles of incidence. Besides, some studies were made for modeling the mechanism of ECE of the proton trajectories with the aim of deriving the critical angle of incidence. 相似文献
1000.
B. Lobe W. Janke K. Binder 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,7(2):283-291
We analyze recently extended high-temperature series expansions for the “Edwards-Anderson” spin-glass susceptibility of the
p-state Potts glass model on d-dimensional hypercubic lattices for the case of a symmetric bimodal distribution of ferro- and antiferromagnetic nearest-neighbor
couplings . In these star-graph expansions up to order 22 in the inverse temperature , the number of Potts states p and the dimension d are kept as free parameters which can take any value. By applying several series analysis techniques to the new series expansions,
this enabled us to determine the critical coupling Kc and the critical exponent of the spin-glass susceptibility in a large region of the two-dimensional (p,d)-parameter space. We discuss the thus obtained information with emphasis on the lower and upper critical dimensions of the
model and present a careful comparison with previous estimates for special values of p and d.
Received: 25 May 1998 / Revised and Accepted: 11 August 1998 相似文献