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951.
Computing semiparametric bounds for option prices is a widely studied pricing technique. In contrast to parametric pricing techniques, such as Monte-Carlo simulations, semiparametric pricing techniques do not require strong assumptions about the underlying asset price distribution. We extend classical results in this area. Specifically, we derive closed-form semiparametric bounds for the payoff of a European call option, given up to third-order moment (i.e., mean, variance, and skewness) information on the underlying asset price. We analyze how these bounds tighten the corresponding bounds, when only second-order moment (i.e., mean and variance) information is provided. We describe applications of these results in the context of option pricing; as well as in other areas such as inventory management, and actuarial science. 相似文献
952.
A modified Langmuir–Hinshelwood model based on intrinsic reactions was proposed. Similar to the Langmuir–Hinshelwood model,
the modified model predicts that both the reciprocal of reaction rate constant 1/k
r
and the adsorption rate constant K
s
are linearly proportional to the reciprocal of the square root of light intensity 1/I
1/2
. The validity of the modified kinetic model was verified with the experimental data of dimethyl phthalate (DMP) degradation. 相似文献
953.
Xinghong Zhang Lin Xu Wenbo Han Ling Weng Jiecai Han Shanyi Du 《Solid State Sciences》2009,11(1):156-161
Hot-pressed zirconium diboride (ZrB2) matrix composites containing 0–30 vol% silicon carbide (SiC) whiskers have been investigated to determine the effect of composition (i.e. amount of SiC whiskers) on the microstructure, mechanical properties and thermal properties. With increasing SiC whisker volume contents, the flexural strength and fracture toughness of the composites were improved compared to those of monolithic ZrB2. Flexural strength increased from 629 MPa for pure ZrB2 to 767 MPa for ZrB2–30 vol%SiCw. Likewise, fracture toughness ranged from 5.4 to 7.1 MPa m1/2 over the same composition range. Specific heat capacity increased with SiC whisker addition, while thermal diffusivity and thermal conductivity decreased slightly with the increase of SiC whisker content. 相似文献
954.
An approach for solving Fredholm integral equations of the first kind is proposed for in a reproducing kernel Hilbert space (RKHS). The interest in this problem is strongly motivated by applications to actual prospecting. In many applications one is puzzled by an ill-posed problem in space C[a,b] or L2[a,b], namely, measurements of the experimental data can result in unbounded errors of solutions of the equation. In this work, the representation of solutions for Fredholm integral equations of the first kind is obtained if there are solutions and the stability of solutions is discussed in RKHS. At the same time, a conclusion is obtained that approximate solutions are also stable with respect to ∞ or L2 in RKHS. A numerical experiment shows that the method given in the work is valid. 相似文献
955.
Rapid solidification processing (cooling rate from the interval 105–106 K s−1) was used to prepare deeply undercooled cryolite-alumina melts. Such prepared samples were analyzed by the XRD method. Besides
cryolite, XRD patterns belonging to ι-Al2O3 were recorded. The influence of annealing on the XRD patterns of deeply undercooled melts was also investigated. 相似文献
956.
In pH 5.5 phosphate buffer solution,N-n-undecyl-N'-(sodium-p-amino-benzenesulfonate)thiourea(UPT)produced a pair of redox peaks on the bare glassy carbon electrode.At the multi-walled carbon nanotube(MWNT)modified electrode,the electrochemical behavior of UPT enhanced greatly.In the presence of bovine serum albumin (BSA),the peak currents of UPT decreased linearly due to the formation of a super-molecular complex.This method was successfully applied to the determination of BSA in a bovine serum sample. 相似文献
957.
杜利民 《广西民族大学学报》1998,(4)
本文试图从科技发展的史实出发,论述了奇异观点在科技发展中所起的积极作用.对科技文稿中出现的奇异观点,往往凭编辑的直觉和专家的评审都无法作出客观的评价.本文提出一种非常规的处理方法,目的是使筛选的失误率降低到最低的限度,以发挥科技期刊的应有作用. 相似文献
958.
提出了一种基于SNMP的客户机端软件中实现MIB库多变量访问的方法,据此方法在HP3000/715工作站HP-UX上开发的相应网络管理系统软件中的基模块-NMSS实现了对MIB数据库中多变量的访问,即可根据网络管理用户的要求,动态地收集各异种网络设备MIB库中的多变量统计数据,以掌握网络当前的各层状态,从而进一步实施网络管理的各项功能。 相似文献
959.
本文提出了甲醇装置烃类转化反应器的动态数学模型,并对此多变量系统进行关联分析和解耦控制系统的设计;还提出了基于数学模型的CH_4值在线估计技术,最终实现了以反应气体中CH_4值为主控变量的串级解耦控制方案。 相似文献
960.
Due to the low absorption contrast of plant tissues, traditional x-ray radiography has not been included in the microscopic techniques used in the identification of traditional Chinese medicines (TCMs). With the development of x-ray phase contrast imaging (XPCI) in recent years, weakly absorbing materials could also be imaged by x- rays. Here we investigate microstructures of TCMs utilizing XPCI based on a nano-focus x-ray tube. The results demonstrated that XPCI is capable of revealing the microstructures of TCMs used as judging criteria in the identification of TCMs. The major advantages of the new method are nondestructivity, no special demand for sample preparation and suitability for thick samples. 相似文献