THE TERM STRUCTURE OF INTEREST RATES AS A GAUSSIAN RANDOM FIELD

A simple model of the term structure of interest rates is introduced in which the family of instantaneous forward rates evolves as a continuous Gaussian random field. A necessary and sufficient condition for the associated family of discounted zero-coupon bond prices to be martingales is given, permitting the consistent pricing of interest rate contingent claims. Examples of the pricing of interest-rate caps and the situation when the Gaussian random field may be viewed as a deterministic time change of the standard Brownian sheet are discussed.     

《摆脱贫困》中蕴含的精准扶贫理念——习近平精准扶贫理念在福建孕育及实践

习近平扶贫理念随着时代发展而完善,从“摆脱贫困”到“精准扶贫”再到“精准脱贫”,其理念一脉相承,其思想内涵与时俱进,不断拓展深化,形成了从理念到理论再到实践的“知行合一”理论实践体系。习近平在福建任职期间进行了“摆脱贫困”理论及实践探索,提出了许多富有创造性的扶贫脱贫观点,如“扶贫先扶志、念好山海经、科技兴农、建设农村党组织、四下基层、滴水穿石”等,明确了“扶持谁一谁来扶一怎么扶”的扶贫脱贫思路,在精神扶贫、扶贫策略、扶贫路径、扶贫组织保障、多元扶贫力量、脱贫内生动力、脱贫长效机制等方面蕴含着精准扶贫精准脱贫理念。     

Semiparametric time series models driven by latent factor

We introduce a class of semiparametric time series models (SemiParTS) driven by a latent factor process. The proposed SemiParTS class is flexible because, given the latent process, only the conditional mean and variance of the time series are specified. These are the primary features of SemiParTS: (i) no parametric form is assumed for the conditional distribution of the time series given the latent process; (ii) it is suitable for a wide range of data: non-negative, count, bounded, binary, and real-valued time series; (iii) it does not constrain the dispersion parameter to be known. The quasi-likelihood inference is employed in order to estimate the parameters in the mean function. Here, we derive explicit expressions for the marginal moments and for the autocorrelation function of the time series process so that a method of moments can be employed to estimate the dispersion parameter and also the parameters related to the latent process. Simulated results that aim to check the proposed estimation procedure are presented. Forecasting procedures are proposed and evaluated in simulated and real data. Analyses of the number of admissions in a hospital due to asthma and a total insolation time series illustrate the potential for practical situations that involve the proposed models.     

车削圆柱中消除回转体锥度的创新方法

本文阐述了在车削加工专业的实习教学中,圆柱工件表面易产生锥度的原因,消除锥度的传统方法,在车工教学实践中发现的新方法可以方便、有效地消除锥度,具有实用性强的良好效果。通过介绍一种极为方便简捷的操作方法,采用运动合成原理,解决了普通或数控车床加工圆柱体过程中产生锥度的问题。     

Influence analysis for Poisson inverse Gaussian regression models based on the EM algorithm

For Poisson inverse Gaussian regression models, it is very complicated to obtain the influence measures based on the traditional method, because the associated likelihood function involves intractable expressions, such as the modified Bessel function. In this paper, the EM algorithm is employed as a basis to derive diagnostic measures for the models by treating them as a mixed Poisson regression with the weights from the inverse Gaussian distributions. Several diagnostic measures are obtained in both case-deletion model and local influence analysis, based on the conditional expectation of the complete-data log-likelihood function in the EM algorithm. Two numerical examples are given to illustrate the results.     

三相异步电动机疑难分析与处理

现如今电器设备不断更新换代,而对于我们工业中一直使用的三相异步电动机性能及维护也不断的改进,同时其它的电器设备也在不断的升级。下面将给大家讲解下有关三相异步电动机的疑难分析与处理及其它电器设备的使用。     

灵东水库除险加固工程的安全管理

文章分析了水库加固工程施工中的安全隐患,并结合实际论述了安全事故预防、施工现场控制及工程建设系统管理的方法.     

The affine Heston model with correlated Gaussian interest rates for pricing hybrid derivatives

In this article we define a multi-factor equity–interest rate hybrid model with non-zero correlation between the stock and interest rate. The equity part is modeled by the Heston model and we use a Gaussian multi-factor short-rate process. By construction, the model fits in the framework of affine diffusion processes, allowing fast calibration to plain vanilla options. We also provide an efficient Monte Carlo simulation scheme.