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41.
胡秀玲 《价值工程》2014,(26):36-37
红外诊断技术是一种新型诊断技术,为变电设备的热诊断提供了很好的诊断方式,该种诊断方式有着不解体、直观性、快速性、准确性的特征,也适宜用在大面积检测中,同时,该种诊断技术也能够与其他检测方式联合使用,定位故障的具体位置,这就可以有效提升检修的便利性。但是,影响红外线热成像诊断技术准确率的因素是多种多样的,在进行诊断时,必须要合理地控制其测量环境与测量方式。本文主要分析影响红外线热成像诊断技术准确性的因素,并提出相关的解决措施。  相似文献   
42.
《Finance Research Letters》2014,11(2):161-172
We consider the valuation of European quanto call options in an incomplete market where the domestic and foreign forward interest rates are allowed to exhibit regime shifts under the Heath–Jarrow–Morton (HJM) framework, and the foreign price dynamics is exogenously driven by a regime switching jump-diffusion model with Markov-modulated Poisson processes. We derive closed-form solutions for four different types of quanto call options, which include: options struck in a foreign currency, a foreign equity call struck in domestic currency, a foreign equity call option with a guaranteed exchange rate, and an equity-linked foreign exchange-rate call.  相似文献   
43.
金融业在现代经济中发挥着极其重要的作用,而金融创新是金融业持续发展的源泉,人才又是金融创新的关键。文章首先运用GM(1,1)模型对我国2012年-2020年金融业人才需求量做了预测,随后根据2009年金融创新人才的占比,以金融业从业人员的平均增长速度作为金融创新人才需求量的平均增长速度推算出了2012年-2020年金融创新人才需求量的占比,最后根据金融业人才需求量和金融创新人才需求量的占比预测出了2012年-2020年金融创新人才需求量,并根据预测结果提出了相关的建议。  相似文献   
44.
Most of the existing pricing models of variance derivative products assume continuous sampling of the realized variance processes, though actual contractual specifications compute the realized variance based on sampling at discrete times. We present a general analytic approach for pricing discretely sampled generalized variance swaps under the stochastic volatility models with simultaneous jumps in the asset price and variance processes. The resulting pricing formula of the gamma swap is in closed form while those of the corridor variance swaps and conditional variance swaps take the form of one‐dimensional Fourier integrals. We also verify through analytic calculations the convergence of the asymptotic limit of the pricing formulas of the discretely sampled generalized variance swaps under vanishing sampling interval to the analytic pricing formulas of the continuously sampled counterparts. The proposed methodology can be applied to any affine model and other higher moments swaps as well. We examine the exposure to convexity (volatility of variance) and skew (correlation between the equity returns and variance process) of these discretely sampled generalized variance swaps. We explore the impact on the fair strike prices of these exotic variance swaps with respect to different sets of parameter values, like varying sampling frequencies, jump intensity, and width of the monitoring corridor.  相似文献   
45.
The purpose of this paper is to evaluate the board roles that make a board effective in the performance of adopting corporate social responsibility (CSR) practices. This paper examines directors' perceptions of the three main roles: monitoring, service, and strategic, which provide tools for critically understanding how the board adds the value in moving the organization towards more CSR practices. The stakeholder theory is used to distinguish the influence of the three main roles on the adoption of CSR practices. Primary data were collected for this research by conducting structured questionnaires with a sample of 461 directors from Saudi listed companies for study purpose. The results show that an appropriate mix of directors' roles and the development of sound board monitoring and service roles are the most crucial determinants of CSR adoption in Saudi listed companies. As the extant corporate governance and CSR literatures do not provide a clear perspective with contradictory outcomes about board roles in influencing CSR practices, the originality of this research is its contribution by evaluating the directors' perceptions of developing a direct relationship between the board roles and the adoption of CSR practices. Furthermore, the use of the stakeholder theory provides additional insights into identifying the most influential board role factors enhancing stakeholders' expectations of CSR practices.  相似文献   
46.
Under the general affine jump-diffusion framework of Duffie et al. [Econometrica, 2000, 68, 1343–1376], this paper proposes an alternative pricing methodology for European-style forward start options that does not require any parallel optimization routine to ensure square integrability. Therefore, the proposed methodology is shown to possess a better accuracy–efficiency trade-off than the usual and more general approach initiated by Hong [Forward Smile and Derivative Pricing. Working paper, UBS, 2004] that is based on the knowledge of the forward characteristic function. Explicit pricing solutions are also offered under the nested jump-diffusion setting proposed by Bakshi et al. [J. Finance, 1997, 52, 2003–2049], which accommodates stochastic volatility and stochastic interest rates, and different integration schemes are numerically tested.  相似文献   
47.
基于红外图像的林火识别方法及实现   总被引:1,自引:0,他引:1  
森林火灾是一种突发性强、破坏性大且处置救助较为困难的自然灾害,会对森林、森林生态系统和人类带来一定危害和损失。早期的林火判别多基于温度、烟雾以及24小时图像监测实现,主观性强,标准单一,且误报率高。如何快速发现林火目标并及时报警扑灭,已经成为国内外学者研究的热点之一。文章基于红外热像仪,对大量森林背景及模拟林火状态进行了图像和温度数据的采集,首次提出了基于温度标准差方法进行热源识别的概念,得出了不同地点、不同时间段森林背景的温度标准差分布,以及明火温度在各阶段的波动范围,为林火的预防和监测提供了重要依据。同时,通过对干扰源进入前后的红外图像进行预处理和分析,对比目标热源的像素面积变化率及其圆形度,即可准确实现部分干扰热源的排除。实验结果证明,将此基于红外图像的热源初判原则与干扰源排除的规律应用于林火监测,方法简单有效,准确率高,对降低森林火灾的发生率,提高社会经济效益有着重要的作用。  相似文献   
48.
In recent decades, undesirable environmental changes, such as global warming and greenhouse gases emission, have raised worldwide concerns. In order to achieve higher growth rate, environmental problems emerged from economic activities have turned into a controversial issue. The aim of this study is to investigate the effect of financial development on environmental quality in Iran. For this purpose, the statistical data over the period from 1970 to 2011 were used. Also by using the Auto Regression Model Distributed Lag (ARDL), short-term and long-term relationships among the variables of model were estimated and analyzed. The results show that financial development accelerates the degradation of the environment; however, the increase in trade openness reduces the damage to environment in Iran. Error correction coefficient shows that in each period, 53% of imbalances would be justified and will approach their long-run procedure. Structural stability tests show that the estimated coefficients were stable over the period.  相似文献   
49.
酒店业的高速发展以及顾客的期望值不断提高,如何利用CRM系统来提升客人的满意度,以达到提升酒店竞争力是酒店需要关注的,本文对客户关系管理(CRM)理论研究和国内星级酒店CRM中存在的问题进行分析,最后以三亚丽思卡尔顿酒店基于企业文化创建的CRM系统值得我国国内酒店学习和借鉴。  相似文献   
50.
Using a wavelet-based decomposition, this paper exploits the information in the data usually employed in the estimation of DSGE models. A simple New Keynesian model featuring price and wage rigidities is estimated for the United States across different frequencies. The estimations indicate that most structural parameters exhibit a frequency-dependent behavior. The impulse response functions also indicate frequency-dependent responses of output to the exogenous shocks. For lower frequencies, there are more persistent effects, especially for preference and technology shocks.  相似文献   
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