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161.
S. Clement Cooper Philip E. Gustafson 《Journal of Computational and Applied Mathematics》1997,80(2):197-208
A bisequence of complex numbers {μn}−∞∞ determines a strong moment functional
satisfying L[xn] = μn. If
is positive-definite on a bounded interval (a,b) R{0}, then
has an integral representation
, n=0, ±1, ±2,…, and quadrature rules {wni,xni} exist such that μk = ∑i=innsnikwni. This paper is concerned with establishing certain extremal properties of the weights wni and using these properties to obtain maximal mass results satisfied by distributions ψ(x) representing
when only a finite bisequence of moments {μk}k=−nn−1 is given. 相似文献
162.
Asymptotic properties of orthogonal Laurent (L-) polynomialsV n (z), associated with log-normal distributions, are derived by constructive methods. It is shown that the sequences {V 2n (z)} and {V 2n+1 (z)} converge separately (asn→∞) to functionsV (0) (z) andV (1) (z), respectively, both holomorphic in 0<|z|<∞. Explicit Laurent series expansions are obtained, from which it follows that each limit function has essential, isolated singularities atz=0 andz=∞. 相似文献
163.
164.
Clement Leibovitz 《Communications in Mathematical Physics》1970,17(2):177-178
An exact solution of Einstein's equations is presented for a perfect fluid representing a point mass in a Einstein Universe. 相似文献
165.
166.
Spin-dependent sum rules for spectroscopic factors have been fitted to experimental data for the transfer of f nucleons. The fits give the error in absolute normalizations in terms of the percentage error, σ, in relative spectroscopic factors, and evidence is presented that standard distorted wave Born approximation analyses of light-ion induced reactions give σ < 10%. The sum rule analyses then imply f occupancies m agreement with simple shell-model expectations to an accuracy of about 10%. The f occupancy deduced for 51V is completely inconsistent with the results of a Hartree-Fock-Bogolyubov calculation. 相似文献
167.
Spurious resonances occuring in numerical resonating group calculations off the oscillator limit are explained as being due to positive energy bound states. A generalization of Swan's version of the Levinson theorem is given which takes into account these states. 相似文献
168.
Crystallographic and thermal studies have been made on the adducts of thiourea with cyclohexane, cycloheptane, cyclooctane, and tetrahydropyran over the temperature range ?170 to 25°C. All the samples exhibit several transitions, which have been classified. Results from previous work are recalled in order to discuss the possible nature of the transitions. 相似文献
169.
Eloisa Cordoncillo Purification Escribano F. Javier Guaita Clotilde Philippe Bruno Viana Clement Sanchez 《Journal of Sol-Gel Science and Technology》2002,24(2):155-165
Sol-gel matrices have been investigated for some years as potential matrices for rare earth luminescence. Sm3+, Eu3+, Dy3+, Er3+ and Tm3+ optical properties in siloxane-zirconium hybrid matrices prepared at room temperature have been investigated. Even if luminescence efficiency is governed by non-radiative relaxation linked to hydroxyl groups, in these matrices, rare earth fluorescence is always observed but lifetimes and quantum yields are dependent on the elaboration procedure. Eu3+ is used as a probe of the local surrounding around the dopant and the emission and decay profiles measurements in rare earth doped and undoped matrices are presented. 相似文献
170.
Michel F Clement 《Journal of Mathematical Analysis and Applications》1975,51(1):47-55
In systems theory, we need some general framework to take into account various concepts from different fields (automata theory, dynamical systems, optimization theory, etc.). This work is a proposal for such a framework. A decision process model is given with the help of category theory. Sufficient conditions for the validity of the equation of optimality of Bellman are established in this model. This model also generalizes the concept of finite automaton. Thus we unify the concepts of automaton and decision system. Especially, we propose the new concept of “opt-automaton” (automaton which optimizes). 相似文献