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确定了影响可燃气体爆炸上限的特征理化因素,如化学计量浓度、临界压力和燃烧热等,构建了混合物理化参数来表征混合气体的理化特征.将这些参数作为输入变量,分别应用多元线性回归和多元非线性回归方法对二元可燃混合气体爆炸上限与上述混合物理化参数之间的内在相关性进行研究,建立了根据混合物理化参数预测二元可燃混合气体爆炸上限的数学模型.两种方法对训练集的预测平均绝对误差分别为2.39%和1.272%;对测试集的预测平均绝对误差分别为2.185%和1.888%.结果表明,两种模型爆炸上限的预测值与文献值均符合较好,在可接受误差范围之内.该方法的提出为工程上提供了一种预测二元可燃混合气体爆炸上限的新方法. 相似文献
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基于大气环流因子的西南地区干旱预测模型及应用 总被引:1,自引:0,他引:1
为了有效识别西南地区干旱发生的前兆环流信号,基于标准化降水指数(SPI)和环流特征量月值数据,考虑致旱因子与区域干旱的非线性关系,对满足不同线型的非线性因子作线性化处理,筛选出通过显著相关检验的预报因子,基于多元线性回归方法建立了四种西南地区秋季干旱预测模型,比较了四种模型的估计值与西南地区实际干旱指数值。结果表明,在1961~2004年的模型率定期,四种回归模型均通过了显著性水平为0.01的F检验;非线性模型对2005~2012年验证期的干旱试报成功率高于线性模型,且成功预测了2005、2007、2009年的三场西南地区秋季干旱,预见期长达6个月,对数模型对西南秋季干旱预测效果较其他模型更稳定;欧亚及亚洲经向环流、大西洋及北非副高、北半球极涡和西藏高原位势高度等均为西南致旱的显著强信号。非线性因子处理方法适用于西南地区干旱预测建模,且具有潜在应用前景。 相似文献
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针对各种不确定性因素直接影响地下水资源评价结果的可靠性问题,基于多元线性回归模型的统计分析,以地下水开采可靠度为核心,提出了基于多元线性回归模型的地下水开采可靠性分析方法,结合传统多元回归分析与现代工程可靠性分析实现了基于多元线性回归的可靠度分析,并以淮北市地下水开采为例进行了计算分析.结果表明,该方法简单、实用、可行. 相似文献
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水质为水库运行管理的重要因素,水质变量包括溶解氧、总磷、叶绿素a及透明度等,是水库富营养化判定的重要指标。在线性回归法分析的基础上,优化环境因子参数,分别采用多元线性回归模型、径向基函数模型与自适应模糊神经网络推理模型对辽宁省大伙房水库的水质进行预测,并通过平均绝对误差、均方根误差及相关系数判定水质模型的预测效果。结果表明,自适应模糊神经网络推理模型预测效果明显优于多元线性回归模型和径向基神经网络模型,因此自适应模糊神经网络推理模型更适合于大伙房水库的水质预测。 相似文献
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针对高拱坝变形问题,提出应用粒子群算法优化高斯过程回归参数的高拱坝变形预测模型,基于高斯过程回归可将低维非线性关系通过核函数投射到高维线性空间的特点,利用高斯过程回归模型来表征水压、温度、时效等因素与坝体变形之间的非线性关系;同时针对迭代求解高斯过程回归模型的超参数效率低的问题,采用粒子群优化算法全局搜索模型超参数,提高了求解效率。对某高拱坝径向位移的拟合预测结果表明,粒子群优化高斯过程回归模型能较好地表征输入因子与变形之间的关系,预测坝体变形,误差在工程允许范围内,可应用于坝体变形预测分析中。 相似文献
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干旱预测是提高防旱抗旱能力的重要非工程措施。在评价不同时间尺度标准化降水蒸散指数(SSPEI)对河南省干旱识别能力的基础上,以能有效表征河南省干旱状况的SSPEI为模型输出,以基于信息变化率和条件互信息的特征变量选择方法(ICR-CMIFS)筛选得到的河南省主要致旱气候系统指数为模型输入,构建了基于粒子群算法优化极限学习机(PSO-ELM)的干旱预测模型,通过对比该模型与标准极限学习机(ELM)、差分进化算法优化极限学习机(DE-ELM)模型的干旱预测结果,验证PSO-ELM模型在河南省干旱预测中的适用性。结果表明,SSPEI-3能有效识别河南省典型干旱事件,从时间和空间上可较准确地反映河南省干旱状况;ICR-CMIFS筛选出的河南省主要致旱气候系统指数为西太平洋副高面积指数和NINO指数;PSO-ELM模型能较准确地预测河南省干旱,且预测精度优于DE-ELM模型和标准ELM模型,在河南省干旱预测中具有较好的适用性。 相似文献
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《Geothermics》1997,26(2):153-178
Production and injection data from slim holes and large-diameter wells at four geothermal fields (Oguni, Japan; Sumikawa, Japan; Takigami, Japan; Steamboat Hills, U.S.A.) were analyzed in order to establish relationships (1) between injectivity and productivity indices, (2) between productivity/injectivity index and borehole diameter, and (3) between discharge capacity of slim holes and large-diameter wells. The productivity and injectivity indices for boreholes with liquid feedzones are more or less equal. Except for the Oguni boreholes, the productivity and injectivity indices display no correlation with borehole diameter. Thus, the productivity index (or, more importantly, the injectivity index in the absence of discharge data) from a slim hole with a liquid feed can be used to provide a first estimate of the probable discharge capacity of a large-diameter geothermal production well. The large-diameter wells at the Oguni, Sumikawa and Steamboat Hills geothermal fields have a more or less uniform inside diameter, and the discharge capacity of these wells (with liquid feedzones) can be predicted using Pritchett's “scaled maximum discharge rate” in conjunction with discharge data from slim holes. Because of the non-uniform internal diameter for large-diameter Takigami wells, it is not possible to use a simple scaling rule to relate the discharge capacities of slim holes and large-diameter wells at Takigami; therefore, a numerical simulator was used to model the available discharge data from Takigami boreholes. The results of numerical modeling indicate that the flow rate of large-diameter Takigami production wells with liquid feedzones can also be predicted using discharge and injection data from slim holes. 相似文献
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Soobhankar PatiSrikanth Gopalan Uday B. Pal 《International Journal of Hydrogen Energy》2011,36(1):152-159
This paper describes a novel solid oxide membrane (SOM) electrolyzer that can utilize the energy value in any hydrocarbon waste or reductant to lower the energy requirement for hydrogen production from steam. The SOM electrolyzer consists of a one-end closed oxygen-ion-conducting yttria stabilized zirconia (YSZ) tube with Ni-YSZ cathode coated on the outside and liquid metal anode inside the tube. The SOM electrolyzer is operated by feeding steam on the cathodic side and hydrocarbon reductant in the liquid metal anode. By feeding hydrocarbon waste it is possible to lower the chemical potential of oxygen in the liquid metal such that the SOM electrolyzer can spontaneously dissociate steam and generate hydrogen on the cathodic side and oxidize the hydrocarbon waste on the anodic side to produce syn-gas. The rate of these reactions can be increased by applying a small potential across the electrodes. 相似文献
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V. A. Doroshenko A. I. Zelenina L. L. Popenko 《International Journal of Hydrogen Energy》1996,21(11-12)
The sulphur content of liquid hydrocarbon fuels is an important index if their quality. The hydrides of Ni-Zr alloys are prospective catalysts for oil-product hydrodesulphurisation. They allow a higher degree of fuel purification from sulphur and they increase the equipment productivity.Test samples of the catalysts capsulate contacts are received and a method is developed for this process. Their catalytic activity both using the example of the demercaptanization reaction and the extraction of total sulphur from the kerosene fraction is studied. The processes occurring on Ni-Zr alloys due to the interaction with hydrogen are investigated by electron microscopy. 相似文献
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Xiaoti Cui Xingang Li Hong Sui Hong Li 《International Journal of Heat and Mass Transfer》2012,55(21-22):5808-5818
A method for simultaneous heat and multicomponent mass transfer incorporated with the volume of fluid surface tracking method was developed in a two-dimensional inclined channel. The process in the channel includes direct contact condensation of hydrocarbon mixtures with and without noncondensable gas, and distillation effect is also considered. Interfacial transport was performed by a multicomponent phase change model in kinetic forms considering the assumption of thermodynamic equilibrium at the vapor–liquid or vapor/gas–liquid interface using Peng–Robinson equations. The shear-stress transport k–ω turbulence model damped near the vapor–liquid or vapor/gas–liquid interface was used. The hydrocarbon mixtures in both phases were described by five pseudo-components, and Stefan–Maxwell equations were used to describe diffusional interactions in the multicomponent system. Parametric studies were performed to investigate further the model with various boundary conditions. Simulations for a binary system were also performed for a preliminary validation. For the liquid phase, similar trends of the Sherwood numbers were found between the results by simulations and predicted by the Penetration Theory. For the vapor phase, good agreement was observed between the results by empirical correlation and simulations. 相似文献
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《International Journal of Hydrogen Energy》2023,48(51):19564-19579
In petroleum and petrochemical refineries, having precise knowledge regarding H2 solubility in hydrocarbon fuels and feedstocks is critical. In this study, the hydrogen solubility in hydrocarbon fuels was estimated using genetic programming (GP) and group method of data handling (GMDH), two exemplary robust advanced models for generating correlation. To do this, 445 observations derived from labratory findings on hydrogen solubility in 17 different hydrocarbon fuels such as bitumen, atmospheric residue, heavy coking gas oil, heavy virgin gas oil, light virgin gas oil, straight run gas oil, shale fuel oil, dephenolated shale fuel oil, diesel, hydrogenated coal liquid, coal liquid, and coal oil, over a large interval of P- operating pressures and T-temperatures were collected. Temperature, pressure, as well as density at 20 °C, molecular weight, and weight percentage of carbon (C) and hydrogen (H) in hydrocarbon fuels, were used as input parameters in developing robust correlations. The outcomes showed the GMDH approach is more precise compared to the GP, with a root mean square error (RMSE) of 0.053302 and a determination coefficient (R2) of 0.9641. Additionally, sensitivity analysis showed that pressure, followed by temperature and H (wt%) of hydrocarbon fuels, has the greatest impact on hydrogen solubility in hydrocarbon fuels. Ultimately, the Leverage method's results suggested that the GMDH model could be relied on to predict hydrogen solubility in hydrocarbon fuels. 相似文献
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中碳强度指数是为全国节能减排行业提供一个以单位国内生产总值(GDP)二氧化碳排放量为载体的指数系统,可有效反映时间序列上地区或行业碳排放强度的变化.2005—2011年中碳强度指数总体呈下降趋势.按中碳强度指数将我国各省级行政区分为五类,其中:大部分地区的指数均集中在0~100之间;指数高于100的四类和五类地区主要是煤炭生产大省和西部欠发达地区;而指数低于0的一类地区主要是经济发达地区.采用对数均值迪氏分解(LMDI)法分析陕西、贵州两省碳强度的影响因素时发现,能源强度下降是其碳强度指数下降的主要原因.结合"十二五"各地区的减排目标,预测了各省级行政区在剩余年份达成目标的压力,结果显示,我国的碳减排任务艰巨,其中内蒙古、宁夏等省份面临巨大的减排压力. 相似文献
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Jean-Christophe Hoguet George P. Karagiannakis Julia A. Valla Christos C. Agrafiotis Athanasios G. Konstandopoulos 《International Journal of Hydrogen Energy》2009
The present work focuses on the development of efficient desulphurization processes for multi-fuel reformers for hydrogen production. Two processes were studied: liquid hydrocarbon desulphurization and H2S removal from reformate gases. For each process, materials with various chemical compositions and microporous structures were synthesized and characterized with respect to their physicochemical properties and desulphurization ability. In the case of liquid phase desulphurization, the adsorption of sulphur compounds contained in diesel fuel under ambient conditions was studied employing as sorbents, zeolite-based materials, i.e. NaY, HY and metal ion-exchanged NaY and HY, as well as a high-surface area activated carbon (AC), for three different diesel fuels with sulphur content varying between 5 and 180 ppmw. Among all sorbents studied, AC showed the best desulphurization performance followed by cerium ion-exchanged HY. The gas phase desulphurization experiments involved the evaluation of zinc-based mixed oxides, synthesized by non-conventional (combustion synthesis) techniques on high steam content reformate gas mixtures. 相似文献
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液态轻烃中的C5、C6组分主要来自油田和炼油化工生产企业,是一种类似于液化气的“绿色能源”,具有安全可靠、经济环保的特点.尤其是近年成功开发的轻烃混空燃气技术,使轻烃具有了特定的市场需求和市场竞争优势,符合国家对能源发展的战略要求.目前,国家住房和城乡建设部已将C5、C6轻烃为原料制成的轻烃燃气确定为“第四代城市燃气”,并要求积极开发和利用轻烃燃气技术,有效利用稳定的轻烃资源,尤其是偏远地区零散的轻烃资源,一方面能有效改善周边城镇居民的生活条件,另一方面能有效提高偏远、低产油田油气资源利用效率.轻烃作为替代燃料,可在一定程度上解决我国石油资源短缺问题,缓解石油供需矛盾,促进能源结构优化,加强资源综合利用.从技术、资源和经济性等方面,分析了地处偏远的西部油田的轻烃就地、就近作为民用燃料加以利用的可行性和优势. 相似文献