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71.
We consider a ruin model with random income and dependence between claim sizes and claim intervals. In this paper, we extend the determinate premium income into a compound Poisson process and assume that the distribution of the time between two claim occurrences depends on the previous claim size.Given the premium size is exponentially distributed, the(Gerber-Shiu) discounted penalty functions is derived.Finally, we consider a similar model.  相似文献   
72.
In this paper, we study the well-posedness of the third-order differential equation with finite delay(P_3): αu'"(t) + u"(t) = Au(t) + Bu'(t) + Fut +f(t)(t ∈ T := [0,2π]) with periodic boundary conditions u(0) = u(2π), u'(0) = u"(2π),u"(0)=u"(2π) in periodic Lebesgue-Bochner spaces Lp(T;X) and periodic Besov spaces B_(p,q)~s(T;X), where A and B are closed linear operators on a Banach space X satisfying D(A) ∩ D(B) ≠ {0}, α≠ 0 is a fixed constant and F is a bounded linear operator from Lp([-2π, 0]; X)(resp. Bp,qs([-2π, 0]; X)) into X, ut is given by ut(s) = u(t + s) when s ∈ [-2π,0]. Necessary and sufficient conditions for the Lp-well-posedness(resp. B_(p,q)~s-well-posedness)of(P_3) are given in the above two function spaces. We also give concrete examples that our abstract results may be applied.  相似文献   
73.
任伟 《数学学报》2019,62(4):647-652
设R■A是环的Frobenius扩张,其中A是右凝聚环,M是任意左A-模.首先证明了_AM是Gorenstein平坦模当且仅当M作为左R-模也是Gorenstein平坦模.其次,证明了Nakayama和Tsuzuku关于平坦维数沿着Frobenius扩张的传递性定理的"Gorenstein版本":若_AM具有有限Gorenstein平坦维数,则Gfd_A(M)=Gfd_R(M).此外,证明了若R■S是可分Frobenius扩张,则任意A-模(不一定具有有限Gorenstein平坦维数),其Gorenstein平坦维数沿着该环扩张是不变的.  相似文献   
74.
We propose an asymmetrical Mach–Zehnder interferometer (MZI) for efficient pulse generation and compression using porous silicon (PS) waveguide, fibre delay line and couplers. We show a pulse compression of about 0.4 ns at the output port with third-order super-Gaussian input pulse in ~2 ns time duration and ~40.3 W peak power level. Also, we show the possibility of obtaining compressed single- or double-pulse with judicious choice of various parameters like input peak power, delay time and input pulse width.  相似文献   
75.
In this paper, using the penalty method in conjunction with graph-convergence, we study the existence of solutions for a class of generalized variational inequalities with variational problem constraints. Our results extend, improve and develop some known results in this field. Our method of proofs is very simple and does not use the hemicontinuity nor the pseudo-continuity properties of monotone operators.  相似文献   
76.
77.
The total energy and electronic structures for type-I (β phase) and type-VIII (α phase) Ba8Ga16Sn30 clathrates under hydrostatic pressure have been investigated using density functional theory (DFT) calculations. It was found that the type-VIII phase is more stable than the type-I one at ambient conditions and that βα phase transition can not occur under hydrostatic pressure. The band structures show that the type-I and type-VIII Ba8Ga16Sn30 are indirect semiconductors with band gaps of 0.24 eV and 0.19 eV, respectively. The results suggested that type-I clathrate Ba8Ga16Sn30 has a larger value of the thermoelectric (TE) power than that of type-VIII clathrate. We found that pressure tuning changes the k-point of conduction band minimum (CBM) in the Brillouin zone for β-phase, but it is not the case for α-phase. Furthermore, the results show that the pressure can change the interaction between guest atoms and the host lattice, and consequently results in the decrease of the band gap of β-phase and the increase of the band gap of α-phase, indicating that the pressure effect can play an important role in the magnitude of the TE power.  相似文献   
78.
Silver-7, 7, 8, 8-tetracyanoquinodimethane (AgTCNQ) microrods are synthesized through the photoelectrochemical catalysis of TiO2 nanoparticles. When illuminated by UV light, Ag nanoclusters deposit on TiO2 nanoparticles dispersed in the AgNO3/alcohol solution. When illuminated by visible light, the metallic Ag on TiO2 nanoparticles will dissolve in the solution as Ag+ while the released electron will be accepted by TCNQ to form TCNQ. Consequently, AgTCNQ microrods are obtained through a photoinduced bipolar mechanism, which is valuable in the chemical synthesis involving cooperative effect or coupling processes.  相似文献   
79.
建立了测定痕量利福平的共振瑞利散射(RRS)法。在NaOH溶液中,利福平与亚甲基蓝相互作用后,共振瑞利散射显著增强,在371 nm处的ΔIRRS最强。利福平的质量浓度在0.20~1.65 mg.L-1范围内与△IRRS成正比,检出限(3Sb/S)为0.038 mg.L-1。该法可用于人体血液及市售利福平药物中利福平含量的测定,结果满意。  相似文献   
80.
罗丹明B-酰肼和8-羟基-7-喹啉醛经缩合反应合成了一个新型的荧光探针(L),其结构经1H NMR,MS和元素分析表征。考察了L对金属离子的识别性能,结果表明:在乙腈溶液[V(MeCN)∶V(H2O)=19∶1,pH7.0]中,L可高选择性的识别Cu(Ⅱ)。Cu(Ⅱ)能诱导L内酰胺结构开环并形成1∶2型的配合物L-Cu(Ⅱ),这一过程是可逆的。  相似文献   
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