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491.
Non‐hyperbolic generalised moveout approximation is a powerful tool to approximate the travel‐time function by using information obtained from two rays. The standard approach for parameter selection is using three parameters defined from zero‐offset ray and two parameters obtained from a reference ray. These parameters include the travel time and travel‐time derivatives of different order. The original parameter selection implies more fit at zero offset compared with offset from a reference ray. We propose an alternative approach for parameter selection within the frame of generalised moveout approximation by transferring more fit from the zero offset to a reference ray by changing in parameter selection. The modified approximation is tested against the original one in few analytical model examples, including the multi‐layered model. 相似文献
492.
Reliable estimation of the timescales of seawater retreat (SWR) in coastal aquifers has significant implications for sustainable groundwater management in coastal areas. Due to the complexity of coastal dynamics, analytical estimates of SWR timescales are limited in number, and numerical models are mainly utilized. Although numerical models allow for accurate analysis of the coastal systems, they concern particular aquifer cases, thus their results are not generally applicable. Here, we perform a dimensional analysis for the depth-integrated freshwater/seawater continuity equations and identify the dimensionless parameters that affect SWR in confined, homogeneous and flux-controlled aquifers. Based on numerical simulations, we gain insight into how these parameters affect SWR, and produce type curves which can be used as a simple tool for estimating SWR timescales in idealized coastal systems, independent of the hydraulic and geometric characteristics of the aquifer. The reliability of our estimates in real-world applications is also discussed. 相似文献
493.
494.
《地学前缘(英文版)》2024,15(1):101693
Stimulating renewable energy consumption is a major focus of the Sustainable Development Goals in combating climate change and global warming. The International Energy Agency estimates that renewable energy consumption should be doubled to achieve the COP21 targets. In this context, the question is whether renewable energy types promote the improvement of ecological quality and economic growth. Most studies have investigated the influence of renewable energy on ecological pollution using carbon dioxide emissions or ecological footprint indicators, which only represent the pollution caused by human consumption patterns, and these indicators neglect the supply side. Motivated by this point, this study uses the LCF (Load Capacity Factor) as an environmental indicator and examines the causality relationship among different types of renewable energy, income, and environmental quality in the USA, while also incorporating employment and capital stock into the analysis. Through using the Fourier causality test with the wavelet-decomposed series, the study explores for the validity of the renewable energy-based growth hypothesis and answers to the question of whether there is a causal effect of renewable energy types on environmental quality. The results demonstrate that there is a bidirectional causality between total renewable energy, wood, biomass, and economic growth as well as between these renewable energy types and the LCF. 相似文献