Predatory trading,Stigma and the Fed׳s Term Auction Facility

Predatory trading may affect the incentives for banks to raise liquidity in times of financial distress. In these periods, borrowing becomes a signal of illiquidity, exposing borrowers to predatory trading and possible insolvency. A stigma of borrowing thus arises, leading distressed banks to take on more illiquid positions than they would otherwise. The Fed׳s Term Auction Facility (TAF) can alleviate this problem. The TAF׳s competitive auction format allows auction winners to signal that they are illiquid but relatively strong. The TAF may therefore be an effective policy tool during financial crises: by altering the signal value of borrowing, this facility supports the injection of liquidity into distressed banks. In normal times, however, this auction facility becomes counterproductive: by cream-skimming the relatively strong banks, the weakest banks are left as potential prey for predators. This suggests that the TAF is a policy best reserved for times of crisis.     

Time varying contagion in EMU government bond spreads

We analyze the time varying behavior of pure contagion effects between Economic and Monetary Union (EMU) government bond spreads before and during the subprime mortgage crisis and the EMU debt crisis. By conducting a rolling window analysis, we are able to monitor the evolution of pure contagion effects and the changing influence of exogenous factors over time. Importantly, this is done without an ex-ante specification of the contagion window. Hence, we are able to determine the exact timing of the start and end for the different contagion periods. In contrast to related studies, we use a slightly different definition of contagious events and show that this approach leads to different conclusions about the progression of the EMU debt crisis. First, the main sources of pure contagion in the later phase of the EMU debt crisis appear to be Italy and Spain and not Greece, Ireland and Portugal. Furthermore, we find that substantial contagion effects among EMU government bond spreads (caused by Ireland and Portugal) already arise during the subprime mortgage crisis and not only during the EMU debt crisis, as one might expect.     

窗墙比对室内热舒适性指标PMV影响的研究

通过建立数学模型进行数值模拟计算,在相同节能改造方案下,对窗墙比与热舒适性之间的变化关系进行了研究。研究表明：窗墙比为0.2时室内舒适性指标较高,但窗墙比为0.32和0.4时的室内舒适性指标基本相同,而且窗墙比为0.32时的室内舒适性指标稍小于窗墙比为0.4时的室内舒适性指标,这与通常窗户越小越舒适的说法有所不同。     

旧有建筑外窗节能改造的实用选择

通过对旧有建筑外窗的几种节能改造方法的经济节能比较,建议选择既经济又能达到节能要求的方式。     

Persistency of window dressing practices in the U.S. repo markets after the GFC: The unexplored role of the deposit insurance premium

We investigate whether the regulatory improvements made in the aftermath of the global financial crisis have been effective in limiting bank downward window dressing by means of repos in the United States. We find that a strict application of the Basel III regulation wipes out incentives to engage in window dressing to bolster the level of leverage Tier 1 ratio at quarter-end. We also show that the persistency of window dressing is related to the computation of the Federal Deposit Insurance Corporation assessment base, which motivates banks to engage in window dressing to reduce the deposit insurance premium.     

一种咬尾双二进制Turbo码并行译码方案

针对双二进制Turbo译码使用并行、滑动窗联合译码技术时,其咬尾的编码构造和窗分割导致边界状态值难以获取的问题,提出了一种新咬尾Turbo码并行、滑动窗译码方案——扩展交叠方案。该方案采用了边界状态盲估计和滑动窗状态回溯两种新译码技术。相比于传统的边界状态度量传播方法（又称迭代法）,新方法一方面提高了边界状态度量的准确性,从而加快了译码收敛速度,一定程度上减小了高信噪比下的性能损失;另一方面避免了存储前一次译码的迭代度量值,更有利于硬件设计。仿真表明,新方案在64左右的中等窗长下即可消除并行和滑动窗影响,逼近原始无并行无滑动窗译码的性能,且窗长越小,其相较传统迭代法带来的译码性能增益就越明显。该方案具有较好的实用性和应用价值,可以满足5G的高速率、低时延和低存储的数据传输要求。     

Indirect tests of the Haugen-Lakonishok small-firm/January effect hypotheses: window dressing versus performance hedging

Equity mutual fund data from 1976–1993 is used to test hypotheses that distinguish window dressing from performance hedging. No significant difference is found pre/post 1983 in the number of funds choosing non-December fiscal year ends or in the percentage of dollars invested when comparing December/non-December fiscal year ends. Significant differences are found in both January returns for mutual funds with December/non-December fiscal year ends and in one month returns for funds with/without a fiscal year end in the previous month. Therefore, if the small-firm/January effect is portfolio manager related, performance hedging, not window dressing, is the more probable source for the “excess” returns.     

有时限取送混合车辆路径问题的模型及其禁忌搜索算法研究

研究了带时间窗的取送混合车辆路径问题.问题中,每个客户带有取货和送货两个时间窗,每个客户处的取货和送货任务可以通过访问一次全部完成,也可以分两次访问分别完成送货和取货任务.在对该类问题进行描述和取送一体化战略的基础上,建立了有时限取送混合车辆路径问题的数学模型.通过设计一种新的解的表示方法构造了该问题的禁忌搜索算法.实验计算结果表明,用该禁忌搜索算法求解有时限取送混合车辆路径问题,不仅可以取得很好的计算结果,而且收敛速度较快,计算结果也较稳定.     

基于快速OPAST算法的直扩信号PN码序列估计

在直接序列扩频（DSSS）通信对抗系统中,伪码（PN）序列估计是一个重要的研究课题。针对在某些情况下权值向量不收敛的问题,提出了一种基于快速正交投影逼近子空间跟踪（OPAST）算法和滑动窗技术的直扩信号PN码序列估计算法,对非同步接收DSSS信号按照宽窗口分段,利用快速OPAST算法提取主特征向量,滑动窗技术实现码同步。该算法迭代权值向量具有正交性以及良好的收敛性,同时解决了常见相位模糊问题。算法具有较低复杂度,数据存储量少,易于硬件实现与实时处理。仿真结果表明,在-10 dB的较低信噪比背景环境中,该快速OPAST算法可以正确有效地估计出PN码序列。     

Grocers' window displays: The eclipse of a British tradition

By reference to period retailing narratives, this paper examines the changed significance of shop window displays for British grocers with the transition from counter‐based to self‐service from the late 1940s to the 1960s. The ‘well‐dressed’ window showing a selection of goods and price offers became an early casualty of changed retail practices. Opportunities presented by self‐service for comprehensive stock displays and in‐store promotion proved a decisive challenge to the art of the grocer's window display. These displays had been ubiquitous; large and small shops alike tried to impress passers‐by with examples of their stock range. Self‐service shops had different internal space requirements and soon it was more important that potential customers could see the well‐stocked aisles and activity within.