衰减的

This dissertation deals with theoretical and practical aspects of antithetic and common random numbers for variance reduction in simulation of stochastic systems.

本文对复杂系统仿真中的公共随机数和对偶变量法进行了系统的论述，给出了各种条件下实现方差衰减的理论和实验结果，给出了估计一对具有独立和相关分量的向量函数的响应和期望的最优化证明，且推导出在弱条件下的方差衰减。

Compared to wet season, arsenic is difficult to mobile in dry season. Attenuation constant in dry season is 0.3082(1/km), but it is 0.0569(1/km)in wet season. If initial concentration of As was 500μg/L without other contamination source in down stream, arsenic would deceased to 50μg/L in down stream 7.5km in dry season but 40km in down stream 40km. As is dominate species in river running throμgh mining area.

砷在枯水期较丰水期难以迁移，通过计算得到，在枯水期砷的衰减系数K值为0.3082(1/km)，而在丰水期为0.0569(1/km)；在污染口浓度达到500μg/L时，下游没有其它的砷的污染源(或会影响砷衰减的其它污染源)时，枯水期砷会在下游7.5km之后浓度降到50μg/L，而丰水期则要在下游40km之后才能降到同样的值，所以在丰水期砷污染的影响的流域更广。

From the junction temperature-varied optical properties measurement, we find that the luminous efficiency will decay more quickly at low current operation. However, when the current density increases to the saturation capacity of the quantum well, the decay ratio will reach a constant.

在变温的光学特性量测上，由实验结果发现，发光效率在较低电流时会衰减的较快，然而在注入电流达到量子井的饱和量后，其发光效率随接面温度升高衰减的现象则会趋近於固定的比例。

The reasons of the capacity attenuation have primarily to accompany with the Li~+ ion embedding material on discharge process the effect of Jahn-Teller of the occurrence, the deliquescence of the cathode manganese in the material and the decomposition of the electrolyte.

在锂离子电池众多的正极材料中，尖晶石型LiMn_2O_4化合物，由于其原材料资源丰富，价格低，环境污染小，合成工艺简单，成为最有希望取代LiCoO_2的材料，但LiMn_2O_4存在容量衰减大，循环寿命短等问题，阻碍了其商品化应用；容量衰减的原因主要有在放电过程中伴随着Li~+离子嵌入发生的Jahn-Teller效应，正极材(来源：AacBCbd论4b文网www.abclunwen.com)料中的锰的溶解和电解液的分解。

The decrease of conductivity of jet fuel with static dissipator additive T1502 during storage was studied and the mechanism of conductivity decrease was discussed.

研究了加入抗静电添加剂的喷气燃料的电导率在储存中的衰减趋势和规律，并讨论了电导率衰减的原因及机理。

In the investigation of Cu-Zn-Al SMA, the influence of quenching speed, shape memory thermal treatment on SME, microstructure and morphologies was discussed. The changes in morphology and interfaces were in situ metallographic observed during thermal cyclings in order to control the degradation of two way shape memory effect . The stabilization of stress induced martensite variants method and the accordingly changes in microstructure were studied in detail. The mechanism was also compared between SSIM and TWME training method. From the above in situ observation results, the interface structure and especially the twin related A: B type variant pair were examined by HREM to clarify the role of movability of interfaces and the changes in variants orientation in inducing the degradation of the TWME. During developing the Ni-Ti-Hf SMA melt spinning ribbon, it was found the morphology and structure embodied the SME and was directly effected by chemical composition and technique factors, such as the different content of Hf, the speed of copper roller rotation and etc. Therefore, the morphology and structure were extensively examined.

在对Cu-Zn-Al形状记忆合金研究中，研究了提高记忆效应的热处理淬火速度、记忆热处理方式对Cu-Zn-Al形状记忆合金组织结构的影响；为了弄清双程记忆效应衰减的原因，原位动态观察了热循环过程中，合金组织形貌及界面的变化；因形状记忆合金必须经记忆训练才能具有双程记忆效应，系统地研究了应力诱发马氏体稳定化训练方法和这种方法引起的双程记忆合金组织结构的变化，比较了它与双程记忆效应训练方法诱发TWME机制的异同；因在原位动态观察中发现界面可动性及两侧变体取向的变化，伴随着记忆效应的衰减，用HREM详细研究了变体的界面结构，特别是A：B型变体界面结构及变体内部结构。

Then the MEMS solenoid type electromagnetic actuating and novel, frictionless and wear-free, and simple structure are designed for fiber-deflecting type MEMS VOA: One of the two coupled single mode fibers is completely fastened in one of the three aligned U-shaped grooves while the deflectable fiber is partially fixed in another groove with a long front section suspending over the wider groove as a cantilever beam. The two fibers, any one for input and the other for output, are well aligned initially so that the insertion loss is very low. Beside the deflectable fiber is a solenoid microactuator with a U-shaped permalloy core attracting a permalloy piece glued on side of the fiber cantilever so that the fiber is deflected and the optical power coupled between the fibers decreased continuously. Using MEMS solenoid as a continuous actuator and the novel structure of VOA are not seen in literature.

为光纤偏移型MEMS可变光衰减器设计了MEMS螺线管电磁驱动方式以及新颖的避免了静摩擦、磨损而且简单的整体结构形式：在硅基片的三段V形槽结构中，将两个对接单模光纤之一完全固定在基片上，只将另一根光纤的稍后部位固定于基片上而使其前端的一定长度悬空，形成一个悬臂梁结构；初始对准后两根光纤之间的光传输损耗很小；通过U型铁芯MEMS螺线管吸引固定于光纤悬臂梁上的坡莫合金片，驱动光纤悬臂梁连续偏移以使两根光纤之间功率传输系数连续变化，从而达到光功率连续衰减的目的。

Using the degree of depolarization,cause of depolarization was discussed,and the droplet can be viewed as a sphericity in the lighter fog.

衰减的测量是确定室外激光通讯系统可行性的首要因素。1960年Kurnick等[1]研究了由雾引起的红外辐射的衰减。

An optimized fuel mixture ratio is obtained for the test bomb. Experimental results show that the cloud dispersion effect of multi-component solid fuel mixture is better than trinitrotoluene's of the same mass.

实验结果表明，该多元固态混合燃料的云雾分散效果明显优于相同质量的TNT，其爆炸场超压呈衰减-增长-再衰减的变化规律，且具有非常相似的压力场分布。

The studied area is located at the tropical area in Xishuangbanna where biological diversity is very rich but ecosystem is weak and Swidden agriculture is popular. With population growing, extensive cultivation and overuse of soil resources has resulted soil and environmental degradation, and restricted continuous development of countryside.

土壤养分和土壤微生物生长代谢水平的衰退是热带山地退化的重要表现形式，二者的变化基本是一致的，即从热带雨林→ 33a次生林→ 6a轮歇地→ 4a轮歇地→旱谷地→橡胶林→荒草坡呈降低趋势；相对于热带雨林而言，不同利用方式土壤微生物和土壤养分状况均有不同程度的下降，且随退化程度增高减幅增大，土壤微生物衰减的速率比土壤养分的衰减更快。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。