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41.
E. Z. Buthelezi F. Cerutti E. Gadioli G. F. Steyn A. Pepe S. H. Connell A. A. Cowley 《The European Physical Journal A - Hadrons and Nuclei》2006,28(2):193-203
The excitation functions for production of 48 residues in the interaction of 16O with 103Rh have been measured at incident energies varying from about 40 to 400MeV. Their analysis shows that many competing reaction
mechanism contribute to the formation of these residues including complete fusion, break-up-fusion reactions and 16O inelastic scattering. The cross-sections of most of these mechanisms are obtained by independent measurements of the spectra
of intermediate-mass fragments observed in the interaction of 16O on 93Nb. The agreement between measured and calculated excitation functions is satisfactory in most of the cases. 相似文献
42.
研究了Ar和Ar/O_2混合气携带四丁基锡的等离子体聚合规律和膜的组成、结构,分别得到低碳氢含量的金属Sn和SnO_x共混膜。 相似文献
43.
Chun-sheng ZHANG Lian-zeng ZHANG Rong WUDepartment of Mathematics Nankai University Tianjing China 《应用数学学报(英文版)》2002,18(1):153-160
Abstract In the present paper surplus process perturbed by diffusion are considered.The distributions ofthe surplus immediately before and at ruin corresponding to the probabilities of ruin caused by oscillation andruin caused by a claim are studied.Some joint distribution densities are obtained.Techniques from martingaletheory and renewal theory are used. 相似文献
44.
Alexey P. Ilyin Julia N. Peregudova Elena B. Poutsykina Dmitri V. Kravchenko 《Tetrahedron letters》2006,47(15):2649-2653
We present a convenient synthesis of heterocyclic scaffolds using a novel modification of four-component Ugi condensation. Two complementary variants of this useful synthetic strategy provide an efficient one-step assembly of four novel pharmaceutically relevant (hetero)aryl-fused 1,4-oxazepines with different substituents’ profile. 相似文献
45.
Conditions for the convexity of compound geometric tails and compound geometric convolution tails are established. The results are then applied to analyze the convexity of the ruin probability and the Laplace transform of the time to ruin in the classical compound Poisson risk model with and without diffusion. An application to an optimization problem is given. 相似文献
46.
In this paper, we consider the optimal proportional reinsurance strategy in a risk model with multiple dependent classes of insurance business, which extends the work of Liang and Yuen (2014) to the case with the reinsurance premium calculated under the expected value principle and to the model with two or more classes of dependent risks. Under the criterion of maximizing the expected exponential utility, closed-form expressions for the optimal strategies and value function are derived not only for the compound Poisson risk model but also for the diffusion approximation risk model. In particular, we find that the optimal reinsurance strategies under the expected value premium principle are very different from those under the variance premium principle in the diffusion risk model. The former depends not only on the safety loading, time and interest rate, but also on the claim size distributions and the counting processes, while the latter depends only on the safety loading, time and interest rate. Finally, numerical examples are presented to show the impact of model parameters on the optimal strategies. 相似文献
47.
M.J. CapdevilleH. Budzinski 《Trends in analytical chemistry : TRAC》2011,30(4):586-606
We expect drinking water and groundwater samples to be contaminated very little, so they are subject to trace-level analysis. Due to the very low levels of contamination, this sort of analysis requires not only powerful analytical technologies to reach limits around the ng/L level, but also quality-control parameters (e.g., blank and spike samples) to monitor potential contamination or losses during sample treatment. Based on a literature review and laboratory experience, we discuss the problems linked to the difficulties of calculating limits of detection, distinguishing instrumental from methodological limits and preventing false-positive results in cases of sample contamination, or false-negative results in cases of compound losses. When possible, we suggest solutions to compensate for, or to prevent, these problems. 相似文献
48.
The compound negative binomial model,introduced in this paper,is a discrete time version.We discuss the Markov properties of the surplus process,and study the ruin probability and the joint distributions of actuarial random vectors in this model.By the strong Markov property and the mass function of a defective renewal sequence,we obtain the explicit expressions of the ruin probability,the finite-horizon ruin probability,the joint distributions of T,U(T-1),|U(T)| and 0≤inn相似文献
49.
50.