人才流动的增智效应对我国酒店业人才开发的启示

人才是酒店资源中最重要的资源,酒店的人才管理兼具投资性大和流动性强的特点,如何进行有效的人才投资、又防止人才过度流失是酒店人力资源开发和管理中的一个重要课题。按照人才流动的增智效应理论,人才的合理流动将带来酒店业的发展;即使显而易见的酒店业之间的人才流失,也会带来酒店人才开发管理中深层次的增智效应,必将有利于提升酒店管理水平和服务质量,并给出积极的应对策略。     

低压及欠平衡钻井中注气量对井内压力的影响

以多相瞬变流理论为基础,建立了井筒内气液两相流动模型,并对低压欠平衡钻井中注气量对井内压力的影响关系和规律进行计算和分析。计算分析结果表明,注气量对井内压力的影响除与注气量本身大小有关外,还与井深、井眼与钻柱结构尺寸、井内液相流量和性质等因素密切相关。单纯增大注气量并不一定就必然会导致井内压力的降低,这取决于所给条件下构成井筒内气液两相流体的静液压力和流阻间的平衡关系。介绍的模型及方法对确定低压欠平衡钻井过程中各相关参数、地面压缩机组的配置、以及设计方案等有一定指导意义。     

空气中多种醛酮液相色谱法侧定的研究

本文研究了空气中多种醛酮的测定。目前国内仅对空气中甲醛的测定研究较多,国外报导的方法需用萃取、浓缩等一系列前处理过程,方法麻烦,易引入杂质造成污染。本文报导的方法系采用2.4—二硝基苯肼的甲醇强酸溶液吸收空气中醛酮直接注入液相色谱仪中进行分离测定。研究表明:本法分离效果好,重复性好,方法简便,速度快,测定的精密度和准确度符合微量分析误差的要求。     

1981—2014年中国资本服务流量测算——基于截断正态退役分布和几何役龄效率剖面

通过梳理资本核算理论框架,结合中国实际情况测量了1981-2014年资本服务流量。资本分类、组合役龄效率-退役剖面计算、资本回报率确定和初始单位效率生产性资本存量估计等方面与既有研究有所不同。测量结果表明:按照1990年不变价格,各类资本服务流量呈增加趋势,其中无形资产服务流量前期较为波动;设备类服务流量增速最高;总资本服务增长率前期呈V型后期呈倒U型,与GDP增速变动不一致,整体来看前者高于后者;比较发现测量结果高于其它研究,差距先收敛后扩大。     

Backward capacity-filtering for electronics Fabs

In electronics Fabs such as semiconductor Fabs and liquid crystal display (LCD) Fabs, which are capital-intensive, finite-capacity planning is critical to achieving full-capacity production and on-time production. However, existing finite-capacity planning methods do not adequately reflect the actual capacity profiles of an electronics Fab. In this paper, we propose a new Fab-level capacity-filtering procedure to generate finite-capacity plan: a backward capacity-filtering procedure for generating finite-capacity release plan. When developing the Fab-level filtering procedures, we use stage-level capacity-filtering algorithms as a key building block. In this study, we enhance the previous capacity-filtering algorithms proposed by one of the authors in order to facilitate the practical requirements of electronics Fabs. We apply the proposed capacity-filtering method to a modern LCD–TFT Fab in Korea. Performance analyses demonstrate that the proposed method is superior to existing methods.     

Early stopping in seamless phase I/II clinical trials

In recent years, seamless phase I/II clinical trials have drawn much attention, as they consider both toxicity and efficacy endpoints in finding an optimal dose (OD). Engaging an appropriate number of patients in a trial is a challenging task. This paper attempts a dynamic stopping rule to save resources in phase I/II trials. That is, the stopping rule aims to save patients from unnecessary toxic or subtherapeutic doses. We allow a trial to stop early when widths of the confidence intervals for the dose-response parameters become narrower or when the sample size is equal to a predefined size, whichever comes first. The simulation study of dose-response scenarios in various settings demonstrates that the proposed stopping rule can engage an appropriate number of patients. Therefore, we suggest its use in clinical trials.     

Precise large deviations for the difference of two sums of END random variables with heavy tails

Assume that there are two types of insurance contracts in an insurance company, and the ith related claims are denoted by {X_ij, j ? 1}, i = 1, 2. In this article, the asymptotic behaviors of precise large deviations for non random difference ∑^n₁(t)_{j = 1}X_1j ? ∑^n₂(t)_{j = 1}X_2j and random difference ∑^N₁(t)_{j = 1}X_1j ? ∑^N₂(t)_{j = 1}X_2j are investigated, and under several assumptions, some corresponding asymptotic formulas are obtained.     

模拟混相驱动态的拟四组分模型

通常模拟混相驱动态采用组分模型,由于组分模型求解工作量大,计算速度慢,要求输入的参数较多,而这些参数很难取全取准,同时组分模型不易被油藏工程师所掌握。因此,介绍了一种模拟混相驱动态的模拟模型,该模型是在黑油模型基础上发展起来的拟四组分模型,它兼有黑油模型和多组分模型的某些优点,如黑油模型的稳定性好和计算速度快、组分模型的可模拟凝析气藏和混相驱等;给出了数学模型及各种物理参数以及混相流体性质的处理方法。该模型还以SPE为例进行计算,结果与SPE的结果一致,从而验证了本模型的可靠性。     

Adaptive designs for single‐arm phase II trials in oncology

Clinical phase II trials in oncology are conducted to determine whether the activity of a new anticancer treatment is promising enough to merit further investigation. Two‐stage designs are commonly used for this situation to allow for early termination. Designs proposed in the literature so far have the common drawback that the sample sizes for the two stages have to be specified in the protocol and have to be adhered to strictly during the course of the trial. As a consequence, designs that allow a higher extent of flexibility are desirable. In this article, we propose a new adaptive method that allows an arbitrary modification of the sample size of the second stage using the results of the interim analysis or external information while controlling the type I error rate. If the sample size is not changed during the trial, the proposed design shows very similar characteristics to the optimal two‐stage design proposed by Chang et al. (Biometrics 1987; 43:865–874). However, the new design allows the use of mid‐course information for the planning of the second stage, thus meeting practical requirements when performing clinical phase II trials in oncology. Copyright © 2012 John Wiley & Sons, Ltd.     

生产还是消费——中国股市生产资本资产定价模型实证检验

生产资本资产定价模型从企业利润最大化角度出发,推出资产的均衡价格.相较于消费资本资产定价模型,生产资本资产定价模型能更好的满足信息完全和决策者理性的假设条件.本文从生产资本资产定价模型出发,利用现值模型将生产的系统性风险因子,即生产的贝塔因子分解为现金流贝塔和折现率贝塔,并采用社会总投资和股市数据进行实证检验.本文发现生产-现金流贝塔是中国股市的重要定价因子,可较好地解释股权溢价的截面差异.相比之下,消费资本资产定价模型对不同资产之间风险溢价的解释能力较弱.