利用首次积分求解几类二阶非线性常微分方程

本文对几类二阶非线性常微分方程,利用首次积分求得了其通积分公式.     

迷离扑朔的《中藏经》

《中藏经》为古代中医名著之一 ,传说系华佗所撰 ,实为魏晋南北朝人的伪托之作。全书共分三卷 ,上卷和中卷分列天地、阴阳、水火、寒热、脉色、脏腑辨证等 49论 ,下卷专论方药 ,载有附方 68首。本书在中医理论方面多有发挥 ,在临床各科特别是内科、外科、妇科及方剂学方面颇具实用价值 ,在养生保健方面亦有精辟论述 ,是一部具有重要学术价值的中医学著作     

基于问题驱动的"微积分基本公式"教学设计

从实例出发,借助问题驱动,以微积分基本公式讲授为例进行教学设计,意在引导学生发现问题、分析问题、解决问题,从而加深对定理的理解和应用。     

Credibility premium for rate-making systems

Credibility formula has been developed in many fields of actuarial sciences. Based upon Payandeh (2010 Payandeh, A.T. (2010). A new approach to the credibility formula. Insur.: Math. Econ. 46(2):334–338.[Crossref], [Web of Science ®] , [Google Scholar]), this article extends concept of credibility formula to relatively premium of a given rate-making system. More precisely, it calculates Payandeh’s (2010 Payandeh, A.T. (2010). A new approach to the credibility formula. Insur.: Math. Econ. 46(2):334–338.[Crossref], [Web of Science ®] , [Google Scholar]) credibility factor for zero-inflated Poisson gamma distributions with respect to several loss functions. A comparison study has been given.     

我国婴幼儿奶粉安全管理政策效果的实证检验--基于消费者偏好的选择实验研究

为提振国产婴幼儿配方奶粉（Infant Milk Formula,IMF）的社会消费信心,我国政府连续推出多项乳品安全管理政策。基于政策背景的分析,将可追溯信息标签、品牌、产地与销售渠道作为主要属性,设计并实施选择实验,进而运用随机参数Logit模型对消费者支付意愿进行实证分析,据以检验公共管理政策的效果。研究表明,消费者对可追溯信息标签、知名品牌以及海外产地的IMF均有较高支付意愿,但对药店销售IMF的认可度不高。因此,推动国内乳品企业建立可追溯系统、实施兼并重组或海外生产等政策举措可望成为提升消费者信心的有效途径,而药店销售的作用则可能非常有限。     

Multivariate singular spectrum analysis for forecasting revisions to real-time data

Real-time data on national accounts statistics typically undergo an extensive revision process, leading to multiple vintages on the same generic variable. The time between the publication of the initial and final data is a lengthy one and raises the question of how to model and forecast the final vintage of data – an issue that dates from seminal articles by Mankiw et al. [51 Mankiw, N. G., Runkle, M. and Shapiro, M. D. 1984. Are preliminary announcements of the money stock rational forecasts?. J. Monetary Econ., 14: 15–27. [Crossref], [Web of Science ®] [Google Scholar]], Mankiw and Shapiro [52 Mankiw, N. G. and Shapiro, M. D. 1986. News or noise? An analysis of GNP revisions. Surv. Curr. Bus. May, : 20–25.  [Google Scholar]] and Nordhaus [57 Nordhaus, W. D. 1987. Forecasting efficiency: Concepts and applications. Rev. Econ. Stat., 4: 667–674.  [Google Scholar]]. To solve this problem, we develop the non-parametric method of multivariate singular spectrum analysis (MSSA) for multi-vintage data. MSSA is much more flexible than the standard methods of modelling that involve at least one of the restrictive assumptions of linearity, normality and stationarity. The benefits are illustrated with data on the UK index of industrial production: neither the preliminary vintages nor the competing models are as accurate as the forecasts using MSSA.     

论丹·布朗的小说艺术

丹·布朗在小说创作实践中,大胆借鉴影视手法,将特有的小说模式、叙事手法与影视剪辑的闪回技巧完美结合,为小说创作树立了一个成功的范例,建成了具有鲜明个人特色的小说城堡。     

Nonparametric inference for panel count data with competing risks

In survival and reliability studies, panel count data arise when we investigate a recurrent event process and each study subject is observed only at discrete time points. If recurrent events of several types are possible, we obtain panel count data with competing risks. Such data arise frequently from transversal studies on recurrent events in demography, epidemiology and reliability experiments where the individuals cannot be observed continuously. In the present paper, we propose an isotonic regression estimator for the cause specific mean function of the underlying recurrent event process of a competing risks panel count data. Further, a nonparametric test is proposed to compare the cause specific mean functions of the panel count competing risks data. Asymptotic properties of the proposed estimator and test statistic are studied. A simulation study is conducted to assess the finite sample behaviour of the proposed estimator and test statistic. Finally, the procedures developed are applied to a real data arising from skin cancer chemo prevention trial.     

Sample Path Asymmetries in Non‐Gaussian Random Processes

We tackle an important although rarely addressed question of accounting for a variety of asymmetries frequently observed in stochastic temporal/spatial records. First, we review some measures intending to capture such asymmetries that have been introduced on various occasions in the past and then propose a family of measures that is motivated by Rice's formula for crossing level distributions of the slope. We utilize those asymmetry measures to demonstrate how a class of second‐order models built on the skewed Laplace distributions can account for sample path asymmetries. It is shown that these models are capable of mimicking not only distributional skewness but also more complex geometrical asymmetries in the sample path such as tilting, front‐back slope asymmetry and time irreversibility. Simple moment‐based estimation techniques are briefly discussed to allow direct application to modelling and fitting actual records.