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1.
在经典风险模型的基础上 ,把索赔到达过程 Nt加以推广为更新过程 ,且认为在保单到达非均匀的前提下 ,设其到达服从更新过程 ,得到一个新的风险模型 :Rt=u+c Mt-∑zti=1Xi(其中 Zt=∑Ntj=1Yj,以下同 ) ,运用马尔可夫骨架过程的理论和方法 ,求得有限时间 t盈余的瞬时分布φ( u,θ0 ,t,a) ,然后求得时刻 t的生存概率Ψ ( t,u,θ0 )。  相似文献   

2.
讨论一类带有投资收益和再保险的变保费双Cox风险模型:U(t)=u+V1(t)=u1+u2+∑〖DD(〗M1(t)〖〗i=1〖DD)〗Xi-∑〖DD(〗M2(t)
〖〗j=1〖DD)〗Zj+u2W(t).假设保单数量过程M1(t)与索赔次数过程M2(t)相依, 使用鞅方法得到了该模型最终破产概率的一个上界表达式e-ru·C(r), 并在特定条件M1(t)=β(t)M2(t)下, 给出了最终破产概率的一个明确上界ψ(u)≤e-Ru, 其中R为Lundberg指数.  相似文献   

3.
文中证明了回归——时间序列混合模型 y_1=β_1x_(t1)+β_2x_(t2)+…+β_px_(tp)+(ut) 其中u(t)为线性过程;中线性过程u(t)自协方差估计的渐近正态性  相似文献   

4.
本文利用Galerkin方法和解的先验估计,研究了一类更广泛的Korteweg-de Vries方程的初边值问题。 u_t+f(u)_x-αu_(xx)+u_(xxx)=0 (x,t)∈R~+×[0,T] u(x,t)|_(t=0)=u_0(x) x∈R~+ u(x,t)|_(x=0)=0 u(x,t)→0 (x→∞)及 u_t+f(u)_x-u_(xxx)=0 u(x,t)|_(t=0)=u_0(x) x∈R~+ u(x,t)|_(x=0)=u_x(x,t)|x=0=0 u(x,t)→0,(x→∞)弱解的存在性,在适当的条件下,还可以得到古典解的存在性。  相似文献   

5.
考察了如下广义BBM Burgres方程ut+f(u) x =uxx+uxxt,u|t =0 =uo(x)→u±,x→∞ . ( 1)稀疏波解的稳定性 ,即在u-0 ,的解 .  相似文献   

6.
本文在Q_Υ={(x,t),-1相似文献   

7.
用锥拉伸与锥压缩不动点定理讨论三阶微分方程周期边值问题u+ρ3u=f(t,u), 0<t<2π;u(i)(0)=u(i)(2π),i=0,1,2.正解的存在性,其中ρ∈0,(1)/(3)为常数,f在t=0,t=2π和u=0处有奇异性.  相似文献   

8.
利用锥不动点定理证明一个二阶奇异周期边值问题- u″(t) +ρ2 u(t) =f(t,u(t) ) ,   0≤ t≤ 2π,u(0 ) =u(2π) ,   u′(0 ) =u′(2π)正解的存在性 ,其中允许 f在 u=0处具有奇性 ,在 u=+∞处超线性 .  相似文献   

9.
本文讨论由初始数据u(X,0)=ψ(X)和附加条件u(x,0,t)=h(x,t),U_x_n(X,0,t)=g(x,t)确定的方程u_t-△u+p(x,t)u_x_i+q(x,t)u=f(X,t)和u_t-△u+p(x,t)u_x+q(x,t)u_x_j=f(X,t)的未知系数p(x,t)和g(x,t)的问题。  相似文献   

10.
在带有投资风险的保险模型Xt=u+a∫t0Xsds+σ∫0tXsdws+∫t0csds-∑iN=1tξi的基础上,对其做相应的推广,并求出推广模型的破产概率上界,然后利用R软件和数值模拟的方法,估计出此保险模型的上界,并将估计值与推导出的理论上界进行比较,考察其精确程度,结果发现理论上界有些偏大。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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