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81.
济阳坳陷下古生界潜山油气藏特征及成藏模式 总被引:1,自引:1,他引:0
济阳坳陷下古生界潜山具有多样性、复杂性的特点,潜山差异性的形成演化、油气成藏主控因素和控藏模式不明确,严重制约了该区潜山油气勘探。在潜山分类的基础上,综合利用系统恢复、分类对比和典型解剖等方法,揭示了济阳坳陷下古生界不同类型潜山的形成演化过程和油气成藏主控因素差异性,分类建立了油气成藏模式。研究表明,济阳坳陷下古生界主要发育高位新盖侵蚀残丘潜山、中位古盖拉张断块潜山、中位新古盖拉张剪切断块潜山、中位中古盖挤压拉张断块潜山和低位古盖拉张滑脱断块潜山5种潜山类型。不同类型潜山的形成演化和油气成藏各具特色,其中,高位新盖侵蚀残丘潜山的发育受隆升、侵蚀作用控制,油气成藏主要受控于油源和盖层条件,表现为"单向供烃、砂体-不整合岩溶体联合输导、残丘控藏"的成藏模式;中位古盖拉张断块潜山的发育受掀斜、断裂作用控制,油气成藏主要受控于储集条件,表现为"单向供烃、顺向断层输导、反向断层控藏"的成藏模式;中位新古盖拉张剪切断块潜山的发育受反转、翘倾和走滑切割作用控制,油气成藏主要受控于输导条件,表现为"多源供烃、断溶体立体输导、断裂控藏"的成藏模式;中位中古盖挤压拉张断块潜山的形成受强烈挤压、拉张滑脱作用控制,油气成藏主要受控于储集条件,表现为"多源供烃、断缝体输导、断褶控藏"的成藏模式;低位古盖拉张滑脱断块潜山的形成受强烈拉张滑脱作用控制,油气成藏主要受控于输导条件,表现为"顶部供烃、断缝体输导、断裂控藏"的成藏模式。 相似文献
82.
热电厂的短期热负荷预测在城市集中供暖中起着至关重要的作用,直接影响热电厂的经济效益和热能利用率。电厂的短期热负荷一般采用神经网络预测模型进行预测,而BP神经网络应用最为广泛。Elman神经网络算法在BP神经网络基础上加入了承接层,作为一步延时算子,实现记忆能力,使系统具备适应时变能力,增强系统全局稳定性。但Elman神经网络算法模型的构造依然需要大量样本的支撑,而且输入层的变量多,导致预测时间依然很长,收敛速度慢。该文在Elman神经网络预测前,进行了相关系数预处理和对样本中异常值的平均化预处理,通过数据归一化运算,使Elman神经网络输入层变量大幅减少。仿真实验表明,改进的Elman神经网络算法使预测模型快速寻优,减少预测时间的同时明显提高预测精度。 相似文献
83.
从时代性、行业性及人力资源价值等方面分析了非线性因素对会计信息质量的影响,认为高质量的会计信息应该反映公司价值,并尝试建立了一个非线性模型,据此大体测算公司价值。 相似文献
84.
Bovine leukemia virus (BLV) is widely prevalent in Japanese dairy farms. To control BLV infections in Japan, segregating or managing cows according to their proviral load (PVL) is a rational strategy. This study was conducted to establish a quantitative procedure for estimating blood PVL per microliter using a statistical model to offer a cost-effective alternative to the conventional quantitative real-time PCR method. In total, 250 Holstein cows infected with BLV were identified from 10 commercial dairy farms. Information on age was collected and blood samples were tested for white blood cell and lymphocyte counts and PVL using PCR. Generalized linear models with quasi-Poisson errors were used to estimate PVL by selecting age, logarithm of lymphocyte count, and their interaction term as explanatory variables. To evaluate the model, blood samples of 92 BLV-infected Holstein cows from 2 other commercial dairy farms were tested, and measured PVL values were compared with estimated PVL values by the model. The logPVL per microliter was modeled by positive associations with log lymphocyte count and age and a negative association with the interaction term. In the evaluation, measured PVL values had a strong correlation with estimated PVL values (Spearman's ρ = 0.87). In conclusion, our model provides a cost-effective and more rapid alternative to the conventional method to facilitate test and segregation or management of BLV-suspected cows. 相似文献
85.
Babak Ghorbani Krishna Vijayaraghavan 《International Journal of Hydrogen Energy》2018,43(20):9733-9748
In the current study, a single cell of a planar SOFC is firstly modeled in 3D using commercial SOFC module of ANSYS Fluent and the results are validated against the experimental investigations in the literature. Many researchers have used ANSYS Fluent for simulating solid oxide fuel cells. However, there is a huge gap in the literature on explaining the detailed procedure that should be followed in order to use this software effectively. A thorough step-by-step approach is presented to provide a deep insight into the software. Thereafter, a simplified quasi-2D method with infinitely shorter computational time is developed and the results are compared with the 3D model. It is found that the reduced model is capable of being utilized as an alternate method for both online diagnosis and designing active control strategies. 相似文献
86.
水平井压裂技术在低渗透及非常规储层中得到了广泛应用,压裂后水平井的产能预测关系到油田开发方案的制定,因此,国内外学者对压后渗流模型的建立和求解方法做出了不懈的努力。本文详细回顾了国内外学者所建压裂水平井产能预测模型及求解方法,指出了不同模型和求解方法的优缺点,并展望了压裂水平井产能模型的发展方向。 相似文献
87.
Vishnu Teja Mantripragada 《Canadian Metallurgical Quarterly》2020,59(2):159-168
ABSTRACTArgon gas is often injected from the bottom of the ladle during steel refining operations. The injected gas interacts with the liquid (metal and slag) bath and enhances the momentum, heat, and mass transfer rate in the melt. However, during these gas–liquid interactions, an opening of the slag layer called slag eye is formed, which exposes the molten metal surface to the atmosphere, which is generally undesirable. In the current work, a transient, three-dimensional mathematical model is used to study the turbulent gas–liquid interactions in single as well as dual bottom blown industrial steelmaking ladles. A Coupled Level Set Volume of Fluid (CLSVOF) model is used for tracking the steel-argon, steel-slag, and argon-slag interfaces, from which the slag-eye area has been predicted. It is found that the inlet gas purging rate, melt height, slag layer thickness, angular and radial positions of the gas inlets affect the slag opening area. Non-dimensional empirical correlations are proposed to predict the slag opening area in both single as well as dual purged ladles, using non-linear regression analysis. 相似文献
88.
针对未考虑正偏心正交车铣切削层几何形状而导致难以全面反映正交车铣切削层几何形状变化规律的问题,基于正交车铣运动规律,在不考虑动力学影响的情况下,对切削层的形成过程进行了静态分析。建立的正偏心正交车铣切削层几何形状的解析模型涉及铣刀侧刃和底刃的切入/切出角度、切削厚度和切削深度。通过试验验证了该解析模型的正确性,并分析了切削参数对铣刀切削层的影响。研究结果为正偏心正交车铣切削层几何形状的变化提供了定量的分析依据,为切削力和颤振的研究提供了理论指导。 相似文献
89.
以开元矿井为例,在水文地质资料基础上,选定合适的指标,根据不同指标的重要程度确定各个指标权重,运用模糊综合评判理论建立矿井水文地质类型划分模型,运用该模型进行水文地质类型评价。 相似文献
90.
This study investigated the oxidation kinetics of silicon-containing steel at 1150–1300 °C using a Simultaneous Thermal Analyzer under atmospheric conditions similar to that of an industry reheating furnace. There is a critical time point for the oxidation kinetics at an oxygen concentration of 4·0 vol.-%., following which the oxidation rate constant increases with the increasing oxidation temperature. The model coefficient A in the kinetic oxidation equation was found to be constant. However, before the critical time point, the oxidation rate constant remained unchanged; the model coefficient A decreased with the increasing temperature. Therefore, the kinetic model of silicon-containing steel for isothermal oxidation was observed to be a modified one on the basis of the experimental data. In addition, the critical time point was prolonged with the increasing isothermal oxidation temperature. Moreover, the oxidation activation energy of the tested silicon-containing steel was 366·16 kJ mol?1. 相似文献