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排序方式: 共有446条查询结果,搜索用时 15 毫秒
41.
为了给地热对井采灌提供示范,为地热资源开发、保护和有效管理提供依据,促进地热资源的可持续开发,研究了延津县下新近系热储层对井采灌试验。研究得出,研究区地温梯度为3.0~3.5℃/hm,延津县城一带由于新乡—商丘断裂的导热作用,地温梯度高于3.5℃/hm,热储水化学类型为Cl-Na型。热储层中存在裂隙或破碎带(高渗通道),热储层的连通构造曲折复杂,但热储层中裂隙不发育;通过分析地热流体的单井回灌试验和生产性对井采灌试验监测数据,总结地热回灌工艺流程及回灌量衰减规律,分析其原因并提出对策。研究可为河南省地热实现对井回灌—开采提供示范和指导。 相似文献
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Blessing Mudavanhu Robert E. O’Malley Jr David B. Williams 《Journal of Engineering Mathematics》2005,53(3-4):301-336
This paper surveys, compares and updates techniques to obtain the asymptotic solution of the weakly nonlinear oscillator equation ÿ + y +ε f(y, $\dot{y}This paper surveys, compares and updates techniques to obtain the asymptotic solution of the weakly nonlinear oscillator equation
? + y +ε f(y,
) =0 as ε → 0 and for corresponding first-order vector systems. The solutions found by the regular perturbation method generally
feature resonance and so break down as t → ∞. The classical methods of averaging and multiple scales eliminate such secular behavior and provide asymptotic solutions
valid for time intervals of length t=O(ε−1). The renormalization group method proposed by Chen et al. [Phys. Rev. E 54 (1996) 376–394] gives equivalent results. Several well-known examples are solved with these methods to demonstrate the
respective techniques and the equivalency of the approximations produced. Finally, an amplitude-equation method is derived
that incorporates the best features of all these techniques. This method is both straightforward to automate with a computer-algebra
system and flexible enough to allow the forcing f to depend on the small parameter
This paper is dedicated to Jerry Kevorkian with sincere appreciation for his long career of dedicated teaching at the University
of Washington and for his substantial contributions to multiscale asymptotics 相似文献
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Increased interconnection has been highlighted as potentially facilitating the integration of wind generation in power systems by increasing the flexibility to balance the variable wind output. This paper utilizes a stochastic unit commitment model to simulate the impacts of increased interconnection for the island of Ireland with large penetrations of wind generation. The results suggest that increased interconnection should reduce average prices in Ireland, and the variability of those prices. The simulations also suggest that while increased interconnection may reduce carbon dioxide emissions in Ireland, Great Britain would experience an increase in emissions, resulting in total emissions remaining almost unchanged. The studies suggest that increased interconnection would not reduce excess wind generation. This is because under unit commitment techniques which incorporate wind power forecasts in the scheduling decisions, wind curtailment is minimal even with low levels of interconnection. As would be expected an increase in interconnection should improve system adequacy considerably with a significant reduction in the number of hours when the load and reserve constraints are not met. 相似文献
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简单阐述了PET、FIT、PBT纤维的发展历程。重点介绍了改性PBT长丝Mirhon WE的特性。 相似文献
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Based on the experimental data,it was clarified that the plastic strain ratio R-value is notequal to Hill's r-value for Ti sheet.From the non-quadratic orthotropic yield function pro-posed recently by the author,an optimal expression between yield stress and r-value for Tisheet was developed on overall investigation.The suitable value of exponent in the functionseems to be 6—8.Thus,an equation was suggested to estimate strength for the pressure vesselmade of Ti sheet. 相似文献
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