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51.
This article employs methodologies based on fractional integration and cointegration to analyse the time-series properties of merger and acquisitions (M&A) activity and crude oil prices in the US from 1980 to 2012. Our results indicate that an increase in the crude oil price produces a significant increase in the M&A data between 2 and 3 months after the initial shock. 相似文献
52.
对与油气管道领域相关的ISO、API、ASME、ASTM、NACE 5所知名国外标准化组织进行了简要介绍,对各组织在提案申请要求、提案内容、尤其是标准制修订流程方面进行了初步对比分析,同时以参与国际标准化组织ISO,为例详细说明了参与国际标准的注意事项及技巧,最后提出了我国在油气管道领域开展标准国际化的启示和建议。 相似文献
53.
We examine the multifractal scaling behavior and market efficiency of China’s clean energy stock indexes using an asymmetric multifractal detrended fluctuation analysis (A-MFDFA) and then investigate the tail correlation between this index and the crude oil market via an asymmetric multifractal detrended cross-correlation analysis (A-MFDCCA). First, we reveal that the overall, upward and downward trends of the clean energy stock indexes all have significant multifractal characteristics. The clean energy stock market is far from efficient regardless of whether the fluctuations are small or large. In addition, both upward and downward fluctuations exhibit considerable asymmetry. The significant gap between the downward and overall trends indicates that the downward trend following small-scale fluctuations implies weaker efficiency for investors. Furthermore,based on the sliding market deficiency measure (MDM),we find that the change in efficiency in the three trends significantly depends on the length of the window. In the short term, there is no significant efficiency difference among these three trends; however, in the long term, the asymmetry in the upward and downward trends has gradually increased,especially after December 2018. The results demonstrate that bear markets can offer considerably more opportunities for obtaining excess profits. Finally, we reveal that the cross-correlation between the trends of crude oil prices and low-carbon indexes exhibits significant multifractal characteristics. When the crude oil market is in a bull market or the low-carbon energy market is in a bear market, especially in a larger-scale fluctuation, investors should pay attention to the long-term influence of the counterparty market and carry out a hedging operation to avoid risks. 相似文献
54.
燃油价格近期受疫情影响出现剧烈波动,国际干散货航运市场也受到巨大影响。基于Clarksons官方数据库1992年1月至2020年4月相关数据,进行实证研究发现,国际燃油价格的暴跌对波罗的海干散货运价指数的下降有着显著的正向影响;燃油价格虽然也在一定程度上受到BDI的影响,但存在一定的滞后性。这有利于干散货运输公司根据燃油价格波动预测运价指数的变化趋势,从而采取多样的方式应对冲击。也对保障干散货运输市场的稳定发展有重要意义。 相似文献
55.
David N. Sattler Holly Berg Sadie R. Grattan Alyssa Nelson Megan Poppe Richard J. Harnish Makayla Shank 《心理学和销售学》2020,37(12):1790-1796
Orangutans are projected to become critically endangered or extinct this century if humans continue to destroy their habitat. Threats include legal and illegal clearcutting of rain forests to establish palm oil plantations, climate change, and transnational organized crime. This study examines how self-benefit and other benefit appeals, knowledge of threats, concern about habitat loss, and liking orangutans are associated with (a) intent to protect habitat due to licit threats and crimes against wildlife, and (b) seeking information to save habitat. Upon entry to a zoo, 251 (118 men, 128 women, and 5 unknown) persons viewed posters highlighting the benefits of habitat conservation to self or others and completed a survey. Concern, threat knowledge, liking, and self-benefit and other benefit appeals accounted for 28% of the variance associated with intent to take action to protect the habitat. Integrating social influence principles into zoo displays and addressing barriers that prevent conservation behavior are discussed. The ideas in this paper are relevant to many primates and endangered species. 相似文献
56.
石油行业是我国工业发展的命脉,能够为国家创造更高的经济价值。但是,这个行业也同样伴随着较高的安全风险。石油井下作业过程往往复杂多变,具有极高的危险性。本文首先列举了石油井下作业事故的类型,接着详细分析了安全事故的发生原因,最后针对发现的问题,提出了相应的应对措施,希望可以对油田井下作业安全防治问题有所帮助。 相似文献
57.
本文根据高酸值原油腐蚀机理,分析了加工高酸值原油对常减压(高酸值原油脱酸装置)装置的腐蚀特点和重点腐蚀部位,并在此基础上提出了具体的防护措施:电脱盐、塔顶"三注"、高温缓蚀剂、腐蚀监测等,并重点介绍了本公司50万吨/年常减压装置的具体防腐措施,实践证明这些措施取得了较好的防腐效果,最后根据实践提出了可行的改进建议。 相似文献
58.
We quantify the reaction of U.S. equity, bond futures, and exchange rate returns to oil price shocks driven by oil inventory news. Across most sectors, equity prices decrease in response to higher oil prices before the 2007/2008 crisis but increase after it. Positive oil price shocks cause a depreciation of the U.S. dollar against a broad range of currencies but have only a modest effect on bond futures returns. The evidence suggests that changes in risk premia help to explain the time-varying effect of oil price shocks on U.S. equity returns. 相似文献
59.
Arieska Wening Sarwosri Johannes Wegmann Oliver Mußhoff 《Journal of Agricultural Economics》2020,71(1):219-238
Despite extensive efforts made by national and international certification agencies, Indonesian smallholder farmers’ participation in palm oil certification schemes adoption remains low. A fundamental obstacle is the smallholder practice of rainforest transformation into oil palm plantation which is forbidden by the agencies. In this context, we investigate three policies that could lead to a reduction in rainforest deforestation by smallholders: price premium on certified palm oil; the provision of environmental information; contributor recognition. In order to evaluate the influence of the policies ex-ante, we conduct a social dilemma experiment involving rubber and oil palm smallholders in Jambi Province, Sumatra, Indonesia. The findings indicate that the price premium and provision of context-specific environmental information could reduce rainforest transformation. However, a statistically significant effect of contributor recognition was not found. 相似文献
60.
本文主要探讨粮油检测数据的科学性和准确性,包括粮油样品的扦取、检测误差的控制、检测质量体系的运行、检测数据处理的原则和检测报告的编制等。 相似文献