话语行为中的弦外之音

本文分析了与英语中的含蓄否定、话语合作原则以及文化默契有关的弦外之音表现形式     

干旱胁迫对克隆植物蕨麻游离脯氨酸含量的影响

研究了干旱胁迫对匍匐茎克隆植物-蕨麻游离脯氨酸含量的影响．实验设置4个处理,即PEG-6000的浓度为0、15％、20％、25％,进行不同时间以及不同渗透强度的处理,重复3次．实验结果表明：随着PEG-6000浓度的增加,除CK的脯氨酸含量逐步增加外,其余处理的脯氨酸含量呈二次曲线变化,在48h时达到最高值,随后脯氨酸的含量开始逐渐下降．     

图书馆馆徽寓意及设计研究

不管是高校校园内的图书馆楼还是城市里的图书馆建筑,普遍以宏伟亮丽而著称,如能配以独具特色的馆徽,展现图书馆独特的文化底蕴,可使其成为图书馆独具魅力的文化品牌。阐述了馆徽的重要作用,结合部分图书馆馆徽实例,对馆徽寓意进行了赏析,并对馆徽的设计和构成元素进行了深入探讨。     

基于GA的编队水下多目标防御火力分配研究

结合舰艇编队对鱼雷防御作战的特点,建立了舰艇编队水下多目标防御火力优化分配模型.为了获得全局最优解,将遗传算法(GA)用于水下多目标防御火力分配优化研究中,给出了基于遗传算法的模型求解方法和步骤.经过实例分析与计算机MATLAB仿真实现,得出编队抗击水下多目标的最优策略,取得了良好的目标分配效果,可为舰艇编队对水下多目标防御作战指挥自动化决策提供科学的参考.     

两性咪唑啉的合成及其缓蚀性能研究

以高纯环烷酸与二乙烯三胺反应合成了中间体咪唑啉,再以去离子水为溶剂,用氯乙酸钠对该中间体进行两性化,制得了水溶性两性咪唑啉缓蚀剂.探讨了反应物配比、反应温度、pH等因素对产物的影响,得出最佳的合成条件为:n(咪唑啉):n(氯乙酸钠)=1:4,90 ℃-95 ℃,pH8-10.在浓缩倍数k=1.5的循环冷却水中用旋转挂片失重法得出:两性咪唑啉用量为20 mg/L时对碳钢的缓蚀率达到97.28%;与HEDP复配后总剂量为20 mg/L时缓蚀率达到99.04%.在模拟油田水中用静态挂片失重法得出:两性咪唑啉与HEDP复配,用量分别为100 mg/L和20 mg/L时,缓蚀率达到91.01%.表9,参7.     

隐性否定的表达方式及其语用功能

结合教学中观察到的实例,从语义和语用学的角度分析了英语隐性否定的主要表达方式和功能。英语隐性否定的表达主要通过词汇和语法手段来实现。除了表示否定意义外,隐性否定在特定的语境中还蕴含着某种言下之意或弦外之音。     

The Information Content of Intraday Implied Volatility for Volatility Forecasting

This study examines the intraday S&P 500 implied volatility index (VIX) to determine when the index contains the most information for volatility forecasting. The findings indicate that, in general, VIX levels around noon are most informative for predicting realized volatility. We posit that the VIX performs better during this time period because trading motivation around noon is less complex, and therefore trades contain more information on the market expectation of future volatility. Further investigation on the 2008 financial crisis period suggests that market participants become more cautious, and thus the forecasting performance is sustained until the market's close. Copyright © 2015 John Wiley & Sons, Ltd.     

The Realised–Implied Volatility Relationship: Recent Empirical Evidence from FTSE‐100 Stocks

This paper examines the long‐run relationship between implied and realised volatility for a sample of 16 FTSE‐100 stocks. We find strong evidence of long‐memory, fractional integration in equity volatility and show that this long‐memory characteristic is not an outcome of structural breaks experienced during the sample period. Fractional cointegration between the implied and realised volatility is shown using recently developed rank cointegration tests by Robinson and Yajima (2002). The predictive ability of individual equity options is also examined and composite implied volatility estimates are shown to contain information on future idiosyncratic or stock‐specific risk that is not captured using popular statistical approaches. Implied volatilities on individual UK equities are thus closely related to realised volatility and are an effective forecasting method particularly over medium forecasting horizons. Copyright © 2011 John Wiley & Sons, Ltd.     

The Forecasting Efficacy of Risk‐Neutral Moments for Crude Oil Volatility

This paper examines the information content of implied volatility for crude oil options as it relates to future realized volatility. Using data for the period 1996 to 2011 we find that implied volatility is an effective predictor of the month‐ahead realized volatility. We show that implied volatility subsumes the information content of contemporaneous volatility, and it contains incremental information on future volatility after controlling for contemporaneous volatility. Furthermore, incorporating risk‐neutral skewness, and especially kurtosis, improves the forecasting of realized volatility. Overall, the association between implied volatility and month‐ahead realized volatility is consistent with evidence documented for other asset classes, leading us to conclude that implied volatility serves as a reasonable proxy for expected volatility. Copyright © 2015 John Wiley & Sons, Ltd.     

计算机网络安全技术研究

针对计算机网络系统当中存在的安全问题 ,通过分析信息的安全威胁及系统安全应具备的功能 ,根据网络安全结构层次 ,分析各层次存在的安全问题并给出了实现网络安全的措施 .为了减少系统的故障时间 ,同时对系统冗余和容错的技术进行了探讨 .