英汉虚构位移结构分析

虚构位移表达是对静态场景的一种动态表征形式。在虚构位移结构中,位移词用来描述并不发生实际运动的静态实体,在语言表层凸显静态实体的某种物理运动。利用Langacker认知语法中的射体(trajector)、路标(landm ark)来分析虚构位移的语言结构特点,可以发现隐现在语言结构中的观察者或其视线发生了位移,其中观察者采用顺序扫描来建构语义内容。     

情感符号中的审美人格——《文心雕龙》与《诗品》比较

《文心雕龙》和《诗品》有相近的情感符号：声律、夸饰、事类；又有相异的运动结构：刘勰以总论一枢纽一割情析采构建著作理论体系，钟嵘以三篇序文和60篇评品文章构筑著作结构。同时，情感符号扣理论结构蕴含文艺家的审美人格：刘勰追求“重旨复意”之无我，钟嵘崇尚“无极动心”之无味。     

近断层地震脉冲效应对大跨度桥梁地震响应的影响

历次震害表明，近断层地震的脉冲效应（滑冲 fling step和前导方向性 forward rupture directivity）使得大量土木工程结构产生灾难性的破坏。大跨度桥梁的动力特性决定了这两种不同的脉冲效应都将对其地震响应产生影响。通过选取具有典型脉冲效应的近断层地震记录，检查了三座不同类型的大跨度桥梁的地震响应,并探讨了脉冲效应的影响。结果表明：滑冲效应在长周期的大跨度桥梁关键部位产生数倍于一般地震的位移和内力响应，而加速度脉冲效应可能对位移响应并无太大影响，却对其内力响应具有与滑冲效应同等程度的影响；对于周期较短的拱桥结构，虽然滑冲效应对其部分长振动周期结构的位移响应具有较大的影响，但加速度脉冲对结构内力的影响更为显著。     

A new futility test approach in clinical interim data monitoring

Sequential monitoring of efficacy and safety data has become a vital component of modern clinical trials. It affords companies the opportunity to stop studies early in cases when it appears as if the primary objective will not be achieved or when there is clear evidence that the primary objective has already been met. This paper introduces a new concept of the backward conditional hypothesis test (BCHT) to evaluate clinical trial success. Unlike the regular conditional power approach that relies on the probability that the final study result will be statistically significant based on the current interim look, the BCHT was constructed based on the hypothesis test framework. The framework comprises a significant test level as opposed to the arbitrary fixed futility index utilized in the conditional power method. Additionally, the BCHT has proven to be a uniformly most powerful test. Noteworthy features of the BCHT method compared with the conditional power method will be presented. Copyright © 2012 John Wiley & Sons, Ltd.     

TESTING FOR CONTINUOUS LOCAL MARTINGALES USING THE CROSSING TREE

We present statistical tests for the continuous martingale hypothesis; that is, for whether an observed process is a continuous local martingale, or equivalently a continuous time‐changed Brownian motion. Our technique is based on the concept of the crossing tree. Simulation experiments are used to assess the power of the tests, which is generally higher than that of recently proposed tests using the estimated quadratic variation (i.e. realized volatility). In particular, the crossing tree shows significantly higher power with shorter data sets. We then show results from applying the methodology to five high‐frequency currency exchange rate data sets from 2003. For four of them we show that at small time‐scales (less than 15 minutes or so) the continuous martingale hypothesis is rejected, but not so at larger time‐scales. For the fifth, the hypothesis is rejected at small time‐scales and at some moderate time‐scales, but not all.     

对新时期文学的一种历史性反思——以1978年文学评奖的运作机制为视点

通过1978年文学评奖的运作机制———群众推荐基础上的专家评选,来探讨何种力量以何种方式参与了对新时期文学的建构。提出1978年文学评奖的运作机制与新时期文学的建构之间具有某种深层互动关系：一方面范围极广的群众推荐本身体现了新时期文学的民主化诉求,另一方面专家评选体现了新时期文学对专业化的一定程度上的认同。因而实际上,1978年文学评奖的运作机制在一定程度上表征了对社会主义文学规范的重新阐释和建构。     

线槽状几何场增强模型研究

对几何增强有效场强应用于肖特基接触从而提高碳膜场发射性能的机理进行了理论分析,介绍了一种有效而实用的平面线槽状排列几何模型,并将其与传统的密排型阵列微尖模型进行了比较.发现对比密排型阵列微尖模型,这种平面线槽状几何增强模型与肖特基接触结合后,场发射均匀性、电流密度、发射点密度等各项场发射指标都有很大改善.     

在立几教学中培养学生空间想象力

通过将平面图形折叠成空间图形，并借助实物、模型和加强看图训练和直观图画法训练以推动、加强和发展对三维空间的想象，由此提出培养空间想象力的递进教学方法．     

Efficient computation of the cdf of the maximal difference between a Brownian bridge and its concave majorant

In this paper, we describe two computational methods for calculating the cumulative distribution function and the upper quantiles of the maximal difference between a Brownian bridge and its concave majorant. The first method has two different variants that are both based on a Monte Carlo approach, whereas the second uses the Gaver–Stehfest (GS) algorithm for the numerical inversion of the Laplace transform. If the former method is straightforward to implement, it is very much outperformed by the GS algorithm, which provides a very accurate approximation of the cumulative distribution as well as its upper quantiles. Our numerical work has a direct application in statistics: the maximal difference between a Brownian bridge and its concave majorant arises in connection with a nonparametric test for monotonicity of a density or regression curve on [0,1]. Our results can be used to construct very accurate rejection region for this test at a given asymptotic level.     

Fractional Lévy stable motion time-changed by gamma subordinator

Abstract

In this paper a new stochastic process is introduced by subordinating fractional Lévy stable motion (FLSM) with gamma process. This new process incorporates stochastic volatility in the parent process FLSM. Fractional order moments, tail asymptotic, codifference and persistence of signs long-range dependence of the new process are discussed. A step-by-step procedure for simulations of sample trajectories and estimation of the parameters of the introduced process are given. Our study complements and generalizes the results available on variance-gamma process and fractional Laplace motion in various directions, which are well studied processes in literature.