地方法

Uncertainties exist in either aleatory variability or epistemic uncertainty, but a weighted average of various alternatives in probabilistic seismic hazard analysis and the combination in methodology of PSHA and DSHA (deterministic seismic hazard analysis) should better prevent it from producing an extremely biased output of hazard estimates.

由于输入模型中不确定因素的存在，如输入参数的随机性和科学分析方法本身的不确定性，对分析结果的不确定性需审慎对待。通常对不同的模型或参量，包括地面衰减模型，进行加权平均可较为合理地减小结果的偏差。概率分析和确定性分析方法的结合亦为可取之有效途径。

In this paper,some problems on bivariate Hermite interpolation by polynomial are studied.The concepts of strong H-basis and Hermite interpolation along a plane algebraic curve are proposed.

1引言如所知，光滑函数方法被广泛地应用于计算机辅助几何设计，有限元及散乱数据插值与拟合(Scattered data fitting and interpolation)等领域·在应用该方法过程中，有关光滑或Hermite插值格式及其显式表达式问题的研究是至关重要的一个方面。

The methods are accurate and quick, and can be used for the quality control of allantoin in Corn silk.

所建立的方法能准确、快速地进行定量检测，可作为玉米须中尿囊素的质量控制方法。

It can well solve optimal file allocation problem in engineering.

此方法可以方便地动态改变文件及其拷贝在各台服务器上的分布，能较好地解决工程中的文件优化分配问题。

The debris flow movement on the alluvial fan is simulated with the technology of numerical simulation and GIS.

考虑泥石流在扇形地和沟槽内的运动状态不同，采用不同的方法模拟泥石流在扇形地上和沟槽内的运动过程，更加真实地反映了泥石流的运动和堆积过程。

Initial growths of disturbances are measured by means of hot-wire anemometry. Due to the detected signals with low signal to noise ratio, the coherence function is used to eliminate background noise during data reduction.

在扰动增长的初始阶段，信号的信噪比非常地低，根据相关谱分析方法，应用相干函数，将扰动信号有效地提取出来，测量了初始扰动的增长。

For the present problem of most Xi\'an metro lines passing obliquely through manyactive ground fissure zones,the effect of intersection angle with active ground fissure ofmetro tunnel on metro tunnel lining structure is studied with FEM,and the deformation andfailure characteristics and ranges of influence zones of tunnel are determined.

5针对西安地铁大多数线路斜交穿越地裂缝带的现状，采用有限元数值模拟方法揭示了地铁隧道与地裂缝斜交角度θ对地铁隧道衬砌结构变形破坏的影响规律。

In this thesis,based on the DFT+NEGF first-principles method,we construct a lead-molecule-lead sandwich system with single benzene-based molecule to investigate the relationship between the structure and properties of the molecular devices and the factors that influence properties of the molecular devices.Our computational investigations on these molecular devices are primarily concentrated on the effect of contact geometry between molecules and electrodes,the effect of side groups,the effect of different torsion angle between two phenyl rings and the effect of external electric field.This thesis consists of five chapters:In Chapter one,we mainly introduce the research background and development of the molecular electronics,including the experimental fabrication of molecular electronic components and theoretical simulation methods.Afterwards we discuss the questions that need to be solved in this area.Finally,the main contents of this thesis are listed.In Chapter two,we introduce the theoretical methods used in this thesis, including the main first-principles calculation methods,i.e.,the Density-Functionmethod and nonequilibrium Green\'s function.

本论文拟采用密度泛函理论和非平衡格林函数相结合的第一性原理计算方法，选取苯基小分子作为研究对象，构建了金属电极/有机小分子/金属电极三明治结构体系，系统地研究了苯基分子器件结构的改变与分子电输运性质之间的关系以及影响分子器件电输运性质的相关因素，其中重点研究了分子与电极间可能的接触结构改变、官能团、分子间的扭转角以及外电场对苯基分子电输运性质的影响，本论文主要包括以下五个章节的内容：第一章为综述部分，主要介绍了分子电子学产生的背景、分子器件的研究意义、当前研究分子器件的实验和主要理论方法，以及目前在研究分子器件中存在的一些问题，最后给出了本论文的主要研究内容和技术路线。

Meanwhile, the concentration of Pb,Zn and other heavy metals is rather high in the oxidation zone and decreasesdownward to levels that are unbelievably low for Pb-Zn mine tailings. Theseobservations suggest that heavy metals should be re-immobilized by secondaryminerals, rather than primary minerals, in the oxidation zone, and could be leachedout from suboxic environment due to low rate oxidative dissolution which preventsthe precipitation of secondary minerals in significant amount. Thus, cover scenarioswhich establish a suboxic environment beneath the cover layer might not always beeffective in preventing heavy metal release from mine tailings.Sequential extraction studies indicate that, in addition to heavy metal leaching,oxidation of the mine tailings increased the mobility of residual Zn, and Cu, while Pb remains immobile due to the formation of anglesite (PbSO4). Using the seven-step extraction technique developed by Dold (J. Geochem. Explor., 2003, 80: 55-68), galena dissolves in significant amount at step 2 most probably due to the strong complexing of Pb2+ by acetate, while other metal sulfides dissolve at step 6, which suggest that this extraction technique could not be used to evaluate the mobility of lead in natural environment

重金属含量均低于新鲜尾矿，但以硬化层中的含量最高(Pb、Zn含量分别为0.47%和0.93%)，往下大幅度降低，表明尾矿风化过程中形成的次生矿物对Pb、Zn等重金属元素有较强的固定作用，而次氧化带的淋溶作用造成了金属元素的大量流失；(4)与新鲜尾矿相比，硬化层中铅的可迁移性大大降低，硬化层之下尾矿样品中铅的可迁移性也不同程度降低，这是由于硫化物氧化产生的硫酸根与尾矿中的铅反应形成铅矾(PbSO_4)的缘故；(5)氧化作用使尾矿中的zn、Cu等重金属的可迁移性不同程度地增大，其中对锌的可迁移性影响最大，铜的可迁移性与铁比较相似，铅则容易与硫化物氧化形成的SO_4~(2-)反应形成铅矾(PbSO_4)；(6)为了减少尾矿污染和修复矿山环境，人们提出了各种不同的尾矿覆盖方案，本文的研究结果表明，这些方法不一定能够有效地阻滞污染元素的迁移。

Finally, applications of the anomalous propagation of microwave in tropospheric ducts are discussed: in connection with concrete radar parameters, effects of ducts on radar range and detection performance are discussed, the results obtained are of great value for the overall design of radar systems; by use of the interference standards of ITU-R, the co-ordination area of satellite earth-station under tropospheric ducts environment is studied ; by explaining the relationship between evaporation duct and advection fog, a new way to forecast sea advection fog from evaporation duct is provided.

最后讨论了对流层大气波导环境下电波异常传播特性的应用：结合具体的雷达系统参数，模拟计算了大气波导对雷达作用距离及发现概率的影响，对雷达系统的总体设计具有重要的参考价值；对表面大气波导环境下的卫星地球站通信协调区域进行了确定，从理论上很好地给出了协调距离量级的概念，为卫星地球站与地面微波站之间的协调提供了依据和参考；分析了利用海面蒸发波导来快速预测平流海雾的新方法，完善了平流海雾的预报方法，对海上安全作业和生产具有重要的意义。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。