卫星通信站极化隔离度下降的排查及解决方法

针对卫星通信站接收交叉极化隔离度下降的问题,首先利用Matlab软件绘制了隔离度与 极化角、线圆转换器偏差的关系曲线,然后通过实测值和公式相比较,推导出偏差理论值。 最后,根据推导出的结论,通过工程实践解决了极化隔离度下降的问题,调整后测试的结果 也验证了该方法的可行性。     

Customer capabilities,switching costs,and bank performance

Customers develop switching costs when they invest time and effort to develop capabilities required to optimally use a given product. Such capabilities are likely to be firm specific and cannot be transferred perfectly to competitors' product offerings. Customers who face switching costs are likely to remain with the same firm and consume complementary products that meet their needs. Thus, firms can achieve competitive advantage by exploiting customers' switching costs. In this paper, we hypothesize that the extent to which firms can benefit from customers' switching costs is contingent upon the firms' internal cross‐selling capabilities. We use online banking data to test our hypotheses and find that customers' switching costs contribute to banks' profitability only in the presence of high levels of internal cross‐selling capabilities. Copyright © 2012 John Wiley & Sons, Ltd.     

服务业中顾客转换行为整合模型的实证研究

近年来顾客流失率越来越高,如何防止顾客流失已经成为企业面临的一个重要问题.只有在事前了解顾客流失的原因,采取针对性的措施,才能更好的维持与顾客长期稳固的关系.但是目前对这一现象本身进行分析的实证研究并不多,本文在文献回顾和总结的基础上把影响消费者转换行为的因素分为推动因素,拉动因素以及调节因素三个方面,提出了一个整合模型并进行了实证研究,研究结果发现,拉动因素即替代者的吸引力对顾客转换行为的影响最大,其次才是推动因素,包括高的感知价格,低的服务质量以及负面的口碑传播,转换成本的调节作用在研究中没有得到验证.这说明消费者即使在对原有企业没有任何不满的情况下也会因为发现了更有吸引力的供应商而离开,同时企业自身的一些因素对转换行为也有重要影响.     

Regime switching rough Heston model

This model combines two important stylized features of volatility, the rough behavior consistent with a Hurst parameter less than , and the regime switching property consistent with more long-term economic considerations. It is nevertheless highly tractable in the sense of semianalytic formulae for European options, and permits a partial Monte Carlo method of similar computational speed as the semianalytic formula (at an appropriate number of Monte Carlo simulations). While option prices are relatively insensitive to the choice of Hurst parameter, introducing rough volatility allows for a better fit to the at-the-money skew.     

Rational Inattention in Uncertain Business Cycles

The paper proposes endogenous information choice as a channel through which uncertainty affects price dynamics. I consider a rational inattention model with volatility uncertainty and endogenous information processing capability. According to the model, firms' learning and optimal attention exhibits inertia and asymmetry in response to volatility changes. Firms choose to process more information when uncertainty rises, especially about aggregate conditions, and their pricing behavior changes accordingly. Using a Markov‐switching factor‐augmented vector autoregression (MS‐FAVAR), the paper also documents a significant positive correlation between volatility and firms' responsiveness to macro‐ and microlevel shocks, consistent with model predictions.     

Influence of perceived service fairness on relationship quality and switching intention: an empirical study of restaurant experiences

Restaurants and dining out are an important part of the tourism industry and are a major business in their own right. The purpose of this study was to examine the relationship between perceived service fairness, relationship quality, and switching intention in fine dining restaurants. Data were collected through a convenience sampling method from 164 customers from only fine dining restaurants in the northern region of West Malaysia (Kedah, Perak, Penang, and Perlis States). Unlike all previous studies which have focused exclusively on the role of justice in service failure and recovery, this study considers all-inclusive service delivery contexts. The results of this study showed that all the dimensions of perceived service fairness have a significant relationship with switching intention. In addition, perceived service fairness has a positive relationship with trust in all dimensions except for outcome fairness. Moreover, the results found that among the perceived service fairness dimensions, only procedural fairness and interactional fairness had a positive relationship with commitment and price fairness; outcome fairness was not related to commitment. Finally, the results confirmed the negative and significant relationship between relationship quality (trust and commitment) on switching intention. Managerial implications of these findings are briefly discussed.     

A structural model for credit risk with switching processes and synchronous jumps

This paper studies a switching regime version of Merton's structural model for the pricing of default risk. The default event depends on the total value of the firm's asset modeled by a switching Lévy process. The novelty of this approach is to consider that firm's asset jumps synchronously with a change in the regime. After a discussion of dynamics under the risk neutral measure, two models are presented. In the first one, the default happens at bond maturity, when the firm's value falls below a predetermined barrier. In the second version, the firm can enter bankruptcy at multiple predetermined discrete times. The use of a Markov chain to model switches in hidden external factors makes it possible to capture the effects of changes in trends and volatilities exhibited by default probabilities. With synchronous jumps, the firm's asset and state processes are no longer uncorrelated. Finally, some econometric evidence that switching Lévy processes, with synchronous jumps, fit well historical time series is provided.     

Phillips Curve Instability and Optimal Monetary Policy

Empirical evidence suggests the Phillips curve has flattened over the past few decades. To capture this feature of the data, I develop a framework where firms face a changing cost of price adjustment, which produces a Phillips curve with a slope coefficient that varies over time. To evaluate the implications for monetary policy, I construct the utility‐based welfare criterion where the relative weight on output gap deviations changes synchronously with the slope of the Phillips curve. The systematic component of the rule that implements optimal policy is constant under discretion and commitment.     

钢绞线加固混凝土梁试验研究

采用试验方法,对钢绞线加固混凝土梁进行了研究。试验表明,加固后梁的抗弯承载力和刚度得到提高,这种加固施工方法可行。