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101.
ABSTRACT

A panel smooth transition regression model was adopted to analyse the non-linear impact of oil prices on oil demand. Data for 42 countries was obtained from the International Energy Agency for the time period spanning from January 1990 to June 2017. The results indicate that a threshold value does exist. Furthermore, when the oil price was lower than this threshold value, a positive relationship between oil price and oil demand was observed. When the price of oil was higher than the threshold value, however, a negative relationship between price and demand was found.  相似文献   
102.
在雷达目标跟踪中,系统量测信息通常在球坐标系下获得。为了采用经典卡尔曼滤波算法实现有效目标跟踪,通常采用量测转换方法将非线性量测信息转换到直角坐标系中。针对传统量测转换方法基于量测值计算转换误差统计特性而导致的估计结果有偏问题,提出了一种基于预测值的量测转换方法,并将其与卡尔曼滤波算法相结合,获得了一种基于预测值量测转换的卡尔曼滤波跟踪算法。仿真结果表明,与现有的基于量测转换的卡尔曼滤波算法相比,该算法能在不提高运算量的情况下有效改善目标跟踪效果,跟踪精度提升约20%。  相似文献   
103.
安延杰 《价值工程》2014,(22):65-66
针对350MW机组热力管道振动的情况,从流体系统、管道系统等方面分析原因,并提出治理措施,取得了显著效果。  相似文献   
104.
民营企业通过与政府建立良好的关系获得与国有企业同等待遇,税负是其中重要的一个方面。现有研究从线性的角度分析了政治关联对民营企业税负的影响,实际上,不同政治关联度对税负的影响方向是不同的。以2009-2011年沪深两市A股主板民营上市公司为样本,探讨政治关联是否影响企业税负以及政治关联度的变化对企业综合税负率的影响。研究发现,政治关联有助于降低民营上市公司综合税负率,且政治关联度与综合税负率之间存在倒U型关系。研究还进一步确定了政治关联度的拐点,为政府规制政策的制定提供参考。  相似文献   
105.
Previous studies have investigated asymmetries in the effects of monetary policy on the real economic activity by using either vector autoregressive (VAR)-based regime-switching models with smooth transition technique or Gaussian functions to parameterise the dynamic effects of structural shocks on the economy. These kinds of VAR models assume asymmetry as a short-run relationship between the series since the long-run neutrality hypothesis of money states that monetary policy can only affect productive capacity of the economy in the short run, but not in the long run. The recent theoretical literature shows that this hypothesis is not quite right. Thus, this paper examines the extent to which monetary policy has a long-run asymmetric effect on output in a number of Organisation for Economic Co-operation and Development countries by using a nonlinear hidden cointegration analysis within a likelihood-based panel framework. The findings indicate that there is a long-run relationship between the real interest rate as an indicator of monetary policy and the growth rate of real output in five countries out of nine under review. This gives support for the view that output has responded asymmetrically to the real interest rate changes. The economic implication of our results is that monetary policy affects positive and negative output fluctuations differently.  相似文献   
106.
机械和电子是一对共生体,机械是运动的基础,是运动的实施者;电子是灵魂,是运动的指挥者。二者相互配合,取长补短,相得益彰,共同为人类社会的生产服务。  相似文献   
107.
以实验的角度来研究高速堆垛机结构的动态特性,以实验模态分析求取堆垛机的模态参数和模态振型,为未来堆垛机的结构优化设计及噪声的控制提供依据。  相似文献   
108.
The objective of this article is to predict, both in sample and out of sample, the consumer price index (CPI) of the US economy based on monthly data covering the period of 1980:1–2013:12, using a variety of linear (random walk (RW), autoregressive (AR) and seasonal autoregressive integrated moving average (SARIMA)) and nonlinear (artificial neural network (ANN) and genetic programming (GP)) univariate models. Our results show that, while the SARIMA model is superior relative to other linear and nonlinear models, as it tends to produce smaller forecast errors; statistically, these forecasting gains are not significant relative to higher-order AR and nonlinear models, though simple benchmarks like the RW and AR(1) models are statistically outperformed. Overall, we show that in terms of forecasting the US CPI, accounting for nonlinearity does not necessarily provide us with any statistical gains.  相似文献   
109.
Using quarterly data from 1994 through 2013, this article is the first to use the Hansen and Seo (2002) tests to examine the long-term relationship between real per-capita GDP (PGDP) and real per-capita health care expenditure (PHCE) in Japan with threshold effects. We detect the presence of a threshold cointegrating relationship between the two variables. In addition, we find that error correction adjustments are significantly conducted only through PGDP in a typical regime, whereas both PGDP and PHCE drive the adjustments in the extreme regime. We find that the extreme regime occurred mainly after Q4 2008, implying that the policy introducing the late-stage medical care system for the elderly in April 2008, which expanded the ratio of personal expenses for the elderly, may be effective for attaining a long-run equilibrium between PGDP and PHCE.  相似文献   
110.
为了验证财税政策对居民消费存在的非线性效应, 文章系统考察了因城乡收入差距的第三方外部因素存在差异时, 财税政策对居民消费影响效应的变化情况. 面板门槛计量模型研究发现, 以城乡收入差距门槛值作为外生变量构建的分段函数中, 税收负担和财政支出规模促进居民消费的城乡收入差距绝对数最优区间分别为4015元-7016元和7912元-10323元; 税制结构和财政支出结构促进的城乡收入差距相对数最优区间分别为0.126-0.171和0.127-0.172. 因此, 应当辩证看待政府财税政策对居民消费的影响作用, 促进我国居民消费的关键点在于财税政策的合理制定与实施.  相似文献   
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