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引汉济渭秦岭隧洞工程投资控制的关键问题研究 被引量:5
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作者 李向东 《隧道建设》 北大核心 2017年第9期1090-1096,共7页
为进一步加强引汉济渭秦岭隧洞工程投资的控制,确保陕西省引汉济渭调水工程按期完成,针对水利部概算"编规"的局限性,在现有法律法规和定额的基础上,重点研究了4个关键问题的解决方法:1)"编规"对引水隧洞项目的划分... 为进一步加强引汉济渭秦岭隧洞工程投资的控制,确保陕西省引汉济渭调水工程按期完成,针对水利部概算"编规"的局限性,在现有法律法规和定额的基础上,重点研究了4个关键问题的解决方法:1)"编规"对引水隧洞项目的划分较粗,无法满足秦岭隧洞工区多、费用组成复杂的要求,设计采用金字塔型分工区结构进行概算组织;2)进口硬岩TBM掘进设备购置费高、断面单一,难以反复利用,"编规"仅在石方开挖单价中计取设备折旧费将使施工单位面临巨亏,设计采用折旧费由施工单位和业主分摊的方案达到了风险共担的目的;3)秦岭隧洞最大独头通风距离达到16 km,超越了"编规"最大12 km的极限,设计采用二次曲线拟合,准确确定TBM轴流通风机调整系数;4)"编规"中隧洞排水费已包含在临时设施费内综合考虑,不单独计列,无法适应多次穿越富水层的秦岭隧洞,设计根据预测涌水量和排水方案计算排水费,使概算合理,留有余地。 展开更多
关键词 引汉济渭 秦岭隧洞 投资控制 概算组成 TBM设备购置费分摊 超长距离通风费 隧洞排水费
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A Research and Design on Application of Genetic Algorithm
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作者 Ping Meng Yujie Shi Liujie Sun3 《International Journal of Technology Management》 2014年第9期131-133,共3页
Traditional algorithms of intelligent test paper generation have some shortcomings of slow generating speed, low success probability and poor generating quality. Genetic Algorithm is a random optimization-searching al... Traditional algorithms of intelligent test paper generation have some shortcomings of slow generating speed, low success probability and poor generating quality. Genetic Algorithm is a random optimization-searching algorithm based on probability. In this paper, based on the user' s request of intelligent test paper generation, we establish the mathematical model and object function, and give some improvements in Simple GA for test paper generation. Based on the algorithm, a automatic generating test paper system is designed and implemented. 展开更多
关键词 Genetic Algorithm mathematical model APPLICATION
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Molecule-based modeling of heavy oil
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作者 HORTON Scott R. HOU Zhen +2 位作者 MORENO Brian M. BENNETT Craig A. KLEIN Michael T. 《Science China Chemistry》 SCIE EI CAS 2013年第7期840-847,共8页
A molecular-level kinetics model has been developed for the pyrolysis of heavy residual oil. Resid structure was modeled in terms of three attribute groups: cores, inter-core linkages, and side chains. The concentrati... A molecular-level kinetics model has been developed for the pyrolysis of heavy residual oil. Resid structure was modeled in terms of three attribute groups: cores, inter-core linkages, and side chains. The concentrations of attributes were constrained by probability density functions (PDFs) that were optimized by minimizing the difference between the properties of the computational representation-which were obtained by juxtaposing the attributes-to measured properties, which were obtained by analytical chemistry measurements. Computational tools were used to build a reaction network that was constructed based upon model compounds and their associated kinetics. For cases with an intractable number of species, equations were written in terms of the three attribute groups and the molecular composition was retained implicitly through the juxtaposition. These modeling methods were applied to the Shengli and Daqing resids. The composition of the simulated molecular feedstock fit well with analytical chemistry measurements. After simulated pyrolysis, both resids showed representative increases in the weight fractions of lighter hydrocarbons. Relevant end-use properties were predicted for the product mixtures. 展开更多
关键词 heavy oil resid pyrolysis molecular-level kinetic modeling
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