关于应收账款的管理

随着改革开放的发展和社会主义市场经济的建立,市场竞争越来越激烈,企业在相互竞争中,越来越注重促销手段,赊销成为企业扩大销售,促进利润增加的重要手段之一。但应收账款的拖欠也成为很多企业被拖垮的重要原因之一。本文从应收账款形成的原因出发,阐述了应收账款对企业的影响,并提出了加强应收账款管理的措施。     

损失规避与公平偏好对房地产征收补偿策略的影响

地方政府对土地财政依赖度高,土地征收与出让仍是市县级政府干预地方经济发展的最主要手段,现行房地产征收补偿制度设计忽略了主体策略互动与信念互动对征收补偿的影响。本文在行为博弈分析框架下,通过构建房地产征收主体的收益理论模型及蕴含损失规避和公平偏好的效用模型,研究损失规避与公平偏好对房地产征收补偿策略的影响。理论推演与数值模拟结果表明：一是征收补偿与被征收人的损失规避和公平偏好正相关,与征收人的损失规避负相关,与征收人的公平偏好正相关;二是被征收人接受征收的意愿越强,征收补偿越高。鉴于此,本文认为在房地产征收补偿制度设计上应充分考虑对人性的尊重,对现行房地产征收补偿价格进行行为偏好系数修正,降低征收人损失规避偏好、强化公平偏好、让被征收人公平共享土地增值收益,提高信息透明度推动被征收人对征收补偿的合理预期。     

Sample size calculation for logrank test and prediction of number of events over time

We review and compare existing methods for sample size calculation based on the logrank statistic and recommend the method of Lakatos for its accuracy and flexibility in allowing time-dependent rates of event, loss to follow-up, and noncompliance. We extend the Lakatos method to allow a general follow-up scheme, to handle non-inferiority tests, and to predict the number of events over calendar time. We apply the Lakatos method to the simple nonproportional hazard situation of delayed treatment effect to facilitate the comparison of different weighting methods and to evaluate the performance of the maximum combination tests. We use simulation studies to confirm the validity of the Lakatos method and its extensions.     

Logistic retainment interval dose exploration design for Phase I clinical trials of cytotoxic agents

Phase I studies of a cytotoxic agent often aim to identify the dose that provides an investigator specified target dose-limiting toxicity (DLT) probability. In practice, an initial cohort receives a dose with a putative low DLT probability, and subsequent dosing follows by consecutively deciding whether to retain the current dose, escalate to the adjacent higher dose, or de-escalate to the adjacent lower dose. This article proposes a Phase I design derived using a Bayesian decision-theoretic approach to this sequential decision-making process. The design consecutively chooses the action that minimizes posterior expected loss where the loss reflects the distance on the log-odds scale between the target and the DLT probability of the dose that would be given to the next cohort under the corresponding action. A logistic model is assumed for the log odds of a DLT at the current dose with a weakly informative t-distribution prior centered at the target. The key design parameters are the pre-specified odds ratios for the DLT probabilities at the adjacent higher and lower doses. Dosing rules may be pre-tabulated, as these only depend on the outcomes at the current dose, which greatly facilitates implementation. The recommended default version of the proposed design improves dose selection relative to many established designs across a variety of scenarios.     

地方高校英语教育的“现实性”创新之思考

在地方高等院校英语教育教学中推动“现实性”创新,有两层意义：一是高校英语教材选编内容应涵盖汉语母语文化;二是地方高校英语教学应与地方经济文化发展的现实需求建立联系。作者就如何在高校英语教学中激活汉语母语文化意识,如何使地方院校英语教学有效地服务于地方经济发展与文化输出,进行了思考,给出了方法与对策。     

组合磁光光纤光栅的磁场敏感性分析

磁光光纤光栅是一种具有磁光效应的特殊光栅,可直接用于本征型的磁场传感或通过磁控的方式实现可调光子信息处理。该文采用分段均匀模型分析了几种组合磁光光纤Bragg光栅中左右旋圆偏振光的偏振相关损耗对磁场的敏感性,计算表明,均匀磁光光纤光栅的中心区段对磁场最为敏感。提出了一种比均匀磁光光栅更加灵敏的F-P型组合光栅传感结构,可更好地用于较弱磁场下偏振相关损耗的检测。     

女人的疯癫与女性身份的迷失

从女人如何变疯癫这一视角探寻女性身份的迷失。在父权文化和菲勒斯中心主义社会,女人的疯癫与女性身份的迷失有着天然的联系。通过对伯莎·梅森疯癫的剖析,探寻女性身份迷失之谜。伯莎·梅森是19世纪英国女作家夏洛蒂·勃朗特《简·爱》中的人物,是男主人公罗切斯特的原配妻子。作者力图通过分析这个角色的社会背景及其被扭曲的他者形象,展示其被边缘化的轨迹。从这个边缘和失语的人物身上,可以看出男权社会对女人的歧视和迫害,使人们对女性身份的迷失有一个更深刻的了解,从而解构菲勒斯—逻各斯中心主义的中心地位。     

汽轮机中压缸气动设计中的损失分析

运用计算流体力学(CFD)方法对300 MW汽轮机中压缸的3种反动式改型方案的内部流场进行了数值模拟.根据计算结果分析了不同方案下的流动特性和参数变化,给出了多级效率,并分析了引起级内损失的原因.计算结果表明,反动式与冲动式两种设计方法得到的叶片效率相近;而后部加载叶型能有效抑制二次流,从而降低叶栅损失;叶片的前缘直径及弯曲角度对流场中涡结构有明显的影响.     

Proper Bayes minimax estimators of the normal mean matrix with common unknown variances

This paper addresses the problem of estimating a matrix of the normal means, where the variances are unknown but common. The approach to this problem is provided by a hierarchical Bayes modeling for which the first stage prior for the means is matrix-variate normal distribution with mean zero matrix and a covariance structure and the second stage prior for the covariance is similar to Jeffreys’ rule. The resulting hierarchical Bayes estimators relative to the quadratic loss function belong to a class of matricial shrinkage estimators. Certain conditions are obtained for admissibility and minimaxity of the hierarchical Bayes estimators.     

新巴塞尔协议中信用风险管理IRB法解析

为研究商业银行的信用风险管理问题,对新巴塞尔协议中信用风险管理IRB法进行系统分析,概括其基本框架,并通过详细解析其设定的4种风险要素函数来解释目前我国商业银行在运用各种信用风险管理模型时存在“黑箱”的原因,同时,探讨该方法与各种信用风险管理模型的兼容关系,通过解析信用风险管理模型中各种风险要素函数设定的内在逻辑关系,总结目前我国商业银行应用IRB法时存在的各种数据估计上的困难,从而得出应对各种困难的对策。