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991.
992.
993.
??In this paper, we consider a perturbed compound Poisson risk model with dependence, where the dependence structure for the claim size and the inter-claim time is modeled by a generalized Farlie-Gumbel-Morgenstern copula. The integro equations, the Laplace transforms and the defective renewal equations for the Gerber-Shiu functions are obtained. For exponential claims, some explicit expressions are obtained, and some numerical examples for the ruin probabilities are also provided. 相似文献
994.
受有序样本聚类思想的启发,本文针对期权定价模型中的非对称Possion跳———扩散模型,提出了一种基于标的资产价格历史数据的参数估计方法,并得到了较好的结果。 相似文献
995.
J.YangandP.H.Geil T.C.LongandP.Xu 《高分子科学》2005,(2):137-145
The effect of sintering dispersed and bulk, low molecular weight (Mn = 50,000 Da), nano-emulsion polytetrafluoroethylene (PTFE) particles near their melting point is described. With the nascent particles consisting of ca.75 nm diameter, hexagonal, single crystals, sintering at, e.g., 350℃, results, initially, in merger of neighboring particles,followed by individual molecular motion on the substrate and the formation of folded chain, lamellar single crystals and spherulites, and on-edge ribbons. It is suggested these structures develop, with time, in the mesomorphic “melt”. Sintering of the bulk resin yields extended chain, band structures, as well as folded chain lamellae; end-surface to end-surface merger,possibly by end-to-end polymerization, occurs with increasing time. 相似文献
996.
企业组织变革的影响因素及变革模式实证分析:以新创科技企业为例 总被引:1,自引:0,他引:1
利用因子分析法将影响组织变革的指标变量综合简化,甄别主要影响因素;借助于结构方程模型刻画组织变革的影响因素对于组织变革过程以及组织绩效的影响程度,验证了组织变革动力因素中组织内部因素作用大于外部因素的假设,指出充分利用变革的动力因素比极力排斥阻力因素的组织绩效更高,从而形成基于创新的,强调组织知识和结构创新的新创科技企业组织变革模式。 相似文献
997.
998.
军校课堂教学质量的属性综合评价方法 总被引:3,自引:0,他引:3
运用属性数学理论对军校课堂教学质量进行综合评价.在建立军校课堂教学质量评价指标体系的基础上,给出了军校课堂教学质量的属性综合评价方法,可为军校教学管理部门以及本科教学评价进行合理地课堂教学质量评价提供决策参考.与一般评价方法相比,属性综合评价方法严谨、精细,评价结果更合理、更可靠.应用实例表明了方法的科学有效性. 相似文献
999.
Long‐Cheng Gao Qi‐Wei Pan Yi Yi Xing‐He Fan Xiao‐Fang Chen Qi‐Feng Zhou 《Journal of polymer science. Part A, Polymer chemistry》2005,43(23):5935-5943
A series of rod–coil diblock copolymers, consisting of poly{2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene} as a rigid segment and poly(n‐butyl acrylate) as a flexible part, were successfully prepared through two inverse procedures by atom transfer radical polymerization. The copolymers were characterized by 1H NMR and gel permeation chromatography and had high molecular weights and relatively narrow polydispersities (polydispersity index < 1.20). All the block copolymers synthesized had two distinct glass‐transition temperatures according to differential scanning calorimetry. A polarizing optical microscopy investigation demonstrated the liquid crystallinity of the diblock copolymers. The self‐assembly behaviors in dilute solutions was studied by transmission electron microscopy. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5935–5943, 2005 相似文献
1000.
Casey L. Elkins Taigyoo Park Matthew G. McKee Timothy E. Long 《Journal of polymer science. Part A, Polymer chemistry》2005,43(19):4618-4631
The synthesis and characterization of copolymers containing 2‐ethylhexyl methacrylate and a quadruple‐hydrogen‐bonding site, 2‐ureido‐4[1H]‐pyrimidone methacrylate (UPyMA), are described. An analogous dimeric hydrogen‐bond‐containing copolymer based on 2‐ethylhexyl methacrylate and methacrylic acid (PEHMA‐co‐MAA) was also synthesized for comparative purposes. The glass‐transition temperatures of the poly(2‐ethylhexyl methacrylate‐co‐2‐ureido‐4[1H]‐pyrimidone methacrylate) (PEHMA‐co‐UPyMA) series increased linearly with increasing UPyMA content. Creep compliance measurements as a function of temperature indicated a decrease in the creep compliance with increasing UPyMA content over the range of 1–10 mol % UPyMA. Melt rheological analysis also showed an increase and lengthening of the plateau modulus as a function of frequency with increasing UPyMA content, as well as increasing complex viscosity as a function of temperature. The analogous PEHMA‐co‐MAA copolymer, which contained 11 mol % methacrylic acid, showed, in the melt rheological analysis, behavior similar to that of the PEHMA‐co‐UPyMA copolymer containing only 1 mol % UPyMA units. The multiple‐hydrogen‐bond‐containing copolymers were successfully analyzed with time–temperature superposition for the construction of master curves. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4618–4631, 2005 相似文献