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1.
Yutao Han  Xi Wan 《The World Economy》2019,42(5):1620-1640
In this paper, we investigate whether partial tax coordination is beneficial to countries within and outside a tax union, in which countries are supposed to compete in taxes and infrastructure. Our results demonstrate that a subgroup of countries agreeing on a common tax rate can harm both member and nonmember states. This is in contrast to the classical findings that partial tax harmonisation is Pareto improving. When a minimum tax rate is imposed within a tax union, we demonstrate that it does not necessarily improve the welfare of the member countries. Moreover, both the high‐tax and low‐tax countries can be worse off. This conclusion is at odds with the classical result that a high‐tax country benefits from the imposition of a lower tax bound.  相似文献   
2.
This paper proposes a multivariate distance nonlinear causality test (MDNC) using the partial distance correlation in a time series framework. Partial distance correlation as an extension of the Brownian distance correlation calculates the distance correlation between random vectors X and Y controlling for a random vector Z. Our test can detect nonlinear lagged relationships between time series, and when integrated with machine learning methods it can improve the forecasting power. We apply our method as a feature selection procedure and combine it with the support vector machine and random forests algorithms to study the forecast of the main energy financial time series (oil, coal, and natural gas futures). It shows substantial improvement in forecasting the fuel energy time series in comparison to the classical Granger causality method in time series.  相似文献   
3.
文中介绍了预应力钢筒混凝土管的概念、优越性,并结合山西省万家寨联接段引黄工程的实际施工,总结出了穿越各种地下管线的施工经验。  相似文献   
4.
河口水流、波浪、潮流、泥沙、河床变形二维数学模型   总被引:19,自引:0,他引:19  
根据河口“波浪掀沙,潮流输沙”的泥沙运动机制,引入“波浪幅射应力”反应波浪对水体和泥沙的驱动力.考虑波浪对底部泥沙作用力、波浪对水流挟沙能力的影响及风场对水流和泥沙运动的影响.同时考虑泥沙粒径大小、水体含盐度、含沙量及水流紊动程度等因素对絮凝沉速的影响.用ADI算法求解沿水深平均方程,破开算子法解悬移质不平衡输沙方程及河床变形方程,引入通度概念处理岸滩不规则边界,建立河口水流、波浪、潮流、泥沙、河床变形二维数学模型.通过实测资料及卫星摇感图像对所建数学模型进行检验,表明它可以较好地预测河口泥沙的运动  相似文献   
5.
The study examines the aggregate dividend behavior of U.S. corporations based on the permanent earnings hypothesis. Using annual data of aggregate earnings and dividends from 1871–1993, I find that although managers change dividends proportional to permanent earnings changes, they make revisions with a larger percentage change in dividends than in permanent earnings. The results from the post‐war data show that firms follow a partial adjustment policy with a long‐term dividend payout target in mind and make revisions with a delay. The quarterly data analysis yields results similar to those of the post‐war annual data.  相似文献   
6.
三峡水利枢纽右岸三期工程坝顶预应力门机大梁高度大、跨度长、钢筋密集、结构体型复杂、张拉吨位大、张拉要求高。针对门机大梁以上特点,对梁体模板设计、混凝土浇筑振捣、梁体张拉施工技术难点进行了深入研究。  相似文献   
7.
From the principle of of the Domain Decomposition Method (DDM), we analyse the 2nd-order linear elliptic partial differential problems and link the Separated-Layers Algorithm (SLA) with DDM. The mathematical properties of SLA and numerical example are presented to obtain satisfactory computation results. For general linear differential ones, also are the structure of SLA and its characteristics discussed.  相似文献   
8.
We use a vertical product differentiation model under partial market coverage to study the social welfare optimum and duopoly equilibrium when convex costs of quality provision are either fixed or variable in terms of production. We show the following new results. First, under fixed costs, the social planner charges a uniform price for the single variant that just covers costs of quality provision. Like the duopoly equilibrium, this socially optimal pricing entails a partially uncovered market, but a smaller share of the market is served compared with the duopoly equilibrium. Second, for the variable cost case, it is socially optimal to provide both high‐ and low‐quality variants, but market shares need not be equal. This differs from the result in fully covered markets. Third, in the duopoly equilibrium, the quality spread is too wide under variable costs relative to the social optimum. Under fixed costs, the duopoly produces two variants, but quality is too low relative to the social optimum, which has only one variant.  相似文献   
9.
In several product categories, it is typical to release products sequentially to different markets and customer segments. Conventional knowledge holds that the roles of various product success drivers do not differ significantly across these sequential channels of distribution. The authors examine sequential distribution channels within the motion picture industry and develop a model that proposes that such differences exist between a primary (short- and long-term theatrical box office) and a sequential (video rental) channel. The authors test their model with a sample of 331 motion pictures released in theaters and on video during 1999–2001 using partial least squares. Results reveal differences in the impact of success factors across channels. For example, cultural familiarity enhances box office success but relates negatively to video rental success, and distribution intensity and date of release enhance box office outcomes but have no impact on rental revenues. Thorsten Hennig-Thurau (tht@medien.uni-weimar.cie) is a professor of marketing and media research at Bauhaus-University of Weimar’s Media School and Honorary Visiting Professor of Movie Marketing in the Faculty of Management of Cass Business School, City University London. He has published articles in theJournal of Marketing, theJournal of Service Research, theInternational Journal of Electronic Commerce, theJournal of Interactive Marketing, Psychology & Marketing, and theJournal of Consumer Affairs, among others. He is author of the monograph Relationship Marketing, which has been translated into Chinese. He is member of the editorial board of three journals and serves as reviewer for theJournal of Marketing andMarketing Science. He has won eight Best Article and Best Paper Awards, including the Overall Best Paper Award of the 2005 American Marketing Association Summer Educators’ Conference and the 2002JSR Excellence in Service Research Award. Mark B. Houston (houstonmb@missouri.edu) (PhD, Arizona State University) is the David and Judy O’Neal MBA Professor at the University of Missouri-Columbia. His research on strategy, interfirm relationships, and innovation has been published in leading journals, including theJournal of Marketing, theJournal of Marketing Research, theJournal of Consumer Research, Marketing Science, theJournal of the Academy of Marketing Science, and theJournal of Financial and Quantitative Analysis. He cochaired the 2005 American Marketing Association (AMA) Summer Educators’ Conference and served for two terms as vice president of the AMA’s Technology and Marketing Special Interest Group. Gianfranco Walsh (g.walsh@strath.ac.uk) received his MPhil degree from UMIST (England) and PhD (2001) and Habilitation (2004) degrees from Hanover (Germany). His research focuses on consumer behavior, corporate reputation, and e-commerce. He has presented numerous papers at international conferences. His work has been published in, among others, theAcademy of Marketing Science Review, the International Journal of Electronic Commerce, theJournal of Consumer Affairs, theJournal of Interactive Marketing, theJournal of Macromarketing, and theJournal of Marketing Management. He is the Chair of Marketing and Electronic Retailing at the Institute for Management, University of Koblenz-Landau.  相似文献   
10.
畜禽养殖废水有机物水质水量变化大,有机物、氨氮与磷的浓度较高,直接排放会严重危害环境。通过构建厌氧-好氧序批式反应器(SBR)处理预酸化畜禽养殖废水,分析了不同进水负荷条件下反应器对污染物的去除性能和微生物群落结构的变化规律。结果表明:SBR反应器对高负荷进水中TN、PO3-4—P和COD的平均去除率可分别达到64.5%、97.5%和94.5%。反应器出现NH+4—N和NO2—N亚硝酸同时积累的短程硝化现象,这可能与高进水负荷对氨氧化菌和亚硝酸盐氧化菌的活性和种群的影响有关。与乙酸盐相比,以丙酸盐作碳源时污泥的强化生物除磷活性更高。随着进水负荷的增大,聚糖菌(GAOs)的相对丰度明显升高。四联球状菌(Tetrasphaera)为反应器中始终占优势的聚磷菌(PAOs),对反应器除磷性能有重要贡献。在高有机负荷条件下,SBR内PAOs与GAOs之间不存在明显的底物竞争关系,系统脱氮除磷性能未受影响。  相似文献   
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