收益波动与随机冲击的非对称性影响：中国与美国股票市场的对比

通过讨论股票收益与随机;中击之间的关系,对中国股票市场和美国股票市场进行了对比研究。研究中使用了中国上海和深圳股票市场1990年12月31日至2005年12月30日的两市A股算术平均周指,以及美国股票市场1973年1月2日至2004年月12月30日的标准普尔500周指。在进行经验研究的过程中,分别使用了线性GARCH模型和GJR—GARCH模型计量股票收益的条件波动——即模型中的条件方差。研究发现,中国股票市场自1990年——1995年波动剧烈,之后波动趋于平缓,而美国股票市场在研究期间内收益波动一直处于一定范围内。同时还发现,美国股票市场的随机冲击对股票收益产生非对称性影响,即负冲击使股票收益产生的波动大于正冲击。而在中国股票市场却找不到相似的证据。鉴于对中国股票市场收益波动的研究结果,在剔除1996年以前的数据之后又进行了扩展研究,但是似然比率检验结果表明,正冲击对股票收益的影响还要略强于负冲击。     

简易智能加湿器设计

介绍一种以SPCE061A单片机为核心的湿度控制系统,实现对空气湿度的自动检测及显示。用湿度传感器采集空气中的湿度信号。被采集的模拟信号通过A/D转换后再根据传感器的湿度阻值曲线计算湿度值,并将其显示在数码管上。     

约束稀疏脉冲反演在GX气田开发中的应用研究

GX气田北部地区构造、断层特征较为复杂,地质建模较困难,而约束稀疏脉冲反演是一种基于地震道的反演方法,它是在波阻趋势的约束下,用最少的反射系数脉冲达到合成记录与地震道的最佳匹配。该方法对初始模型依赖性较小,中高频部分不受初始模型的影响,其反演结果能忠于实际地震资料,分辨率与地震资料接近,保真度高。以GX气田为例,通过约束稀疏脉冲反演技术对GX气田开展储层预测,其反演结果与实测井曲线吻合较好,能客观反映地质体在横向上的变化特征,该方法适用于储层横向变化快和非均质性较强的少井区块。     

Optimal adaptation strategies to face shocks on groundwater resources

We consider an exogenous and reversible shock to a groundwater resource, namely a decrease in the recharge rate of the aquifer. We compare optimal extraction paths and the social costs of optimal adaptation in two cases: under certainty, i.e. when the date of occurrence of the shock is known, and under uncertainty, when the date of occurrence of the shock is a random variable. We show that an increase in uncertainty leads to a decrease in precautionary behavior in the short run and to an increase in precautionary behavior in the long run. We apply our model to the particular case of the Western la Mancha aquifer in Spain. We show that, in this context, it is advantageous for the water agency to acquire information on the date of the shock, especially for high-intensity and intermediate-risk events.     

经济长波理论与网络文化产业发展

创新,是经济发展的本质规定。文化,是衡量世界发展的重要尺度。网络文化产业发展,正是一种创新性的发展。它既同经济周期、长波理论紧密关联,又具有反经济周期的特性,呈现出逆势上扬的特点。当然,网络文化产业的反周期与逆势上扬,并不一定是消费者直接付费的增长,而可能是其间接支出的累积,例如广告投入的力度加大。中国网络文化产业,正进入发展的黄金时期。     

If you,tourist, behave irrationally,I’ll find you!

When departures from rational behavior can potentially be expected, modeling should allow for their identification and their quantification. In this regard, prices in tourism might have effects that may not be as apparent as economic theory predicts. This article incorporates the sticker shock formulation into the mixed logit model without imposing consistency with consumer theory to accommodate any possible positive or negative price effects. By allowing the parameters of “price” and “sticker shock term” to take any value – negative or positive – we detect abnormal behaviors in the tourist demand: not only is the negative relationship between price and demand inverted for some people but also some tourists might be willing to accept higher-than-expected prices. The “non-well-behaved” groups' shares are estimated.     

海面低仰角数字微波通信系统性能及体制分析

本文介绍了海面低仰角数字微波通信系统的特点，对海面电波多径衰落进行了理论计算，指出了通信系统抗衰落的方法和手段，并给出了一种抗衰落通信系统在海面通信试验中的测试数据。     

Diversification and performance: evidence from East Asian firms

We examine the impact of diversification on performance for firms operating in different institutional environments during a relatively stable period and during a major economy‐wide shock. We locate our study in six Asian countries at different levels of institutional development. Results indicate that diversification negatively impacts performance in more developed institutional environments while improving performance only in the least developed environments. Even in the least developed institutional environments, diversification offers limited benefits when an economy‐wide shock strikes. Though successful diversifiers are sometimes affiliated with business groups, diversification is associated with poorer performance for both affiliated firms and independent firms. In sum, we find that the outcomes of diversification are influenced by institutional environments, economic stability and affiliation with business groups. Copyright © 2007 John Wiley & Sons, Ltd.     

倏逝波在一维氧化硅亚微米波导线中传输特性的研究

[HTK]基于光学倏逝波原理的光纤或波导传感器是目前光学传感器领域的重要发展方向之一,而倏逝波在其中的传输特性是决定该类传感器敏感特性的关键因数.利用倏逝场理论分析了直径102～103nm的一维氧化硅亚微米光波导在其直径与外部介质(折射率)变化时倏逝波的穿透深度.实验结果表明,亚微米光波导的传输损耗将随着波导尺寸和外部环境折射率的变化而变化,倏逝波的传输方式非常适用于高灵敏度探测,可应用于光化学传感器和生物化学传感器的设计.     

Feminism’s fourth wave: a research agenda for marketing and consumer research

Abstract

Three waves of feminism each reveal a very different relationship with marketing. This commentary considers these relationships in the light of what is now frequently being hailed as the fourth wave, a resurgence of feminism that is driven by younger women who harness the power of the Internet and social media to challenge gender inequity. The commentary looks at what distinguishes the fourth wave from its predecessors and highlights key areas in marketing and consumer research where feminist perspectives are sorely required.