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This paper presents a self-adaptive load balancing algorithm, in which each peer creates a local load distribution view using a passive load statistic method and a local file requested view using file requested statistic method. When load imbalance exists in the system, the heavy loaded peer will make the logical links which point to itself to point to a light loaded peer in its local load distribution view, with the indegree of the heavy loaded peer decreasing and the indegree of the light loaded peer increasing, the load imbalance magnitude will decrease. When the request load of the heavy loaded peer is high, the peer will use its local file request view to get the popular file and cache the file to corresponding target peer.

提出一种自适应负载均衡方法，方法采用一种被动式结点负载统计方法生成局部负载视图；采用一种文件访问统计方法生成局部文件访问视图；当系统内结点负载存在差异，重载结点把指向自身的逻辑链路迁移至指向局部负载视图中的轻载结点，通过减小重载结点入度和增加轻载结点入度来减小结点间负载差异；当结点的请求负载较高时，通过局部文件访问视图计算需要缓存的热点文件及目标结点，降低承载热点文件的结点的请求负载。

In chapter 4, we first discussed the existence of multiple positive solutions of the second order nonsingular Dirichlet boundary value problem for impulsive differential equations by using the fixed point index theorem in cones . Next, we presented some new existence results for singular boundary value problems for second order impulsive differential equations by using fixed point theorem in cones and Leray-Schauder nonlinear alternative theorem.

第四章我们首先利用锥不动点定理讨论了非奇异二阶脉冲微分方程狄利克莱边值问题多个正解的存在性；其次我们用锥不动点定理和Leray-Schauder型非线性抉择定理，讨论了奇异二阶脉冲微分方程狄利克莱边值问题一个及多个正解的存在性。

Our solution is another tip: using None as an index has the same effect as a missing index, so you can get the same functionality programmatically, i.e., when you are using a variable to index through a sequence but also want to be able to access the first or last elements

我们的方案是使用另一个小技巧：用None作为索引值，这样一来就可以满足你的需要，比如说，在你想用一个变量作为索引来遍历从第一个到最后一个元素的时候

Life is like a box of matches, stop using is foolish, but using it indiscriminately is dangerous.

人生好像一盒火柴，严禁使用是愚蠢的，滥用则是危险的。

ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.

本论文针对车载异步电机在矢量控制器所遇到的问题：定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案：分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算，分析出对于电流型逆变器在采用定子磁场定向时，其性能同时具有矢量控制和直接转矩控制两者的优势，并对电压型逆变器在转子磁场定向下的模型进行了仿真研究；建立异步电机非线性模型，推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程，并做出了仿真结果，建立异步电机在非线性模型下的矢量控制调节器的PI参数设计，在实际应用中，若忽略电机电感的动态变化，可以根据当前的磁路饱和状态而在线修正电感参数，从而将非线性方程线性化，降低控制器的复杂度；考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出，本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题；推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通，用于实现高性能的矢量控制算法，并给出了仿真结果；推导出了电动汽车恒转矩给定的闭环回馈制动系统，实现了电动控制模型和制动模型的统一，而且结合铅酸电池最大充电电流的要求，为制动转矩在线给定建立了数学模型；设计了基于双DSP系统的高性能矢量控制器软硬件框图，并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。

Synthesis using known facts (known conditions, important inequation, or has proved inequalities as basis, using inequalities) and relevant theorems of nature, the logical reasoning, the final step out to prove the inequality, its characteristic and the idea is "from" from "guide, known as" to "see", gradually introduced conclusion.

综合法利用已知事实(已知条件、重要不等式或已证明的不等式)作为基础，借助不等式的性质和有关定理，经过逐步的逻辑推理，最后推出所要证明的不等式，其特点和思路是"由因导果"，从"已知"看"需知"，逐步推出"结论"。

According to this understanding, this thesis tries to modify PSO algorithm in order to improve its quality of solutions. The main approches include: using uniform design to ensure the uniform distribution of initial particles in the design space; adding mutation operation to increase the diversity of particles; decreasing the maximum velocity limitation and the velocity inertia automatically to balance the local and the global search efforts; developing a new approach to treat the design variables exceeding the bounds; using extensive local searches to escape local minimum. The overall effect of these approaches can yield better results for most test problems.

有鉴於此，本文针对粒子群演化法之流程参考相关文献并稍作改变，使得粒子群演算法在结果的收敛上更具优势，本文的主要改进的方法包括：应用均匀设计的概念使得初始的粒子可以更均匀地分布在空间上；利用突变增加粒子之间的差异性与多样性；利用适当控制的最大速度限制及惯性权重控制，达到区域搜寻与全域搜寻的效果；应用新的边界处理机制处理设计变数超过上、下限的问题；利用区域强化搜寻针对粒子附近地区，再作进一步的搜索以得到更佳之结果；将各种方法综合后配合粒子群演算法使用，可以得到不错的结果。

Environmental issue has caused widely public concern. In this thesis, the mechanism of calcite cluster structure absorbing environmental infectant has been investigated using quantum chemistry calculation. Using B3LYP calculation method and taking 6-311++G (3df,2pd) basis set in our Gaussian calculations, the results show that the calcite cluster structure can absorb environmental infectant.

在本次研究中，采用了量子化学计算中的B3LYP方法以及6-311++G(3df，2pd)基组进行理论计算，其结果能很好的反映方解石表面分子簇结构吸附环境污染物的情况，为阐明方解石表面分子簇结构吸附环境污染物的机理提供了理论基础。

Results showed that L-THP possessed negative inotropic and negative chronotropic action, lowed left ventricular pressure and it's infinitesimal calculus, decreased heart output in per min., shorten 〓 and 〓 of action potential of ventricular papillary muscle of guinea pig and even the plate-phase of action potential disappeared in larger dose group , but prolonged 〓. we studied transmembrane transportation of 〓 after administering L-THP , L-THP not only depressed uptake and increased release of Ca 2+ in normal myocardium, but also it showed stronger inhibition in cell injured by ISO, and fully eliminated the effect of ISO increasing uptake and decreasing release of 〓. By detecting the 〓 content of ventricular single myocyte using fluorescent probe Fluo-3/AM, results correspond to that done above, L-THP decreased 〓 content inside of cell significantly. Using whole-cell mode, we observed the effect of L-THP on Ica in ventricular single cell, it was found that L-THP decreased Ica, the effect increased with increasing it's dose, and had voltage, frequency-dependency. Dose highly corelated to effect, corelative constant is 0.87. When washing cell with normal tyre's solution, Ica could recover, which proved the blocked action of L-THP on calcium channel once again. Meanwhile, L-THP reduced production of MDA in heart injured by ISO in dose-dependent manner, improved content of GSH-Px, in case tissue or cell free from free radical damage.

结果显示，该药物具有负性肌力和负性频率作用，降低左室压及其微分，终使每分心输出量减少；缩短豚鼠心室乳头肌动作电位时程的〓和APD〓，大剂量使动作电位平台消失，〓延长；同位素示踪法研究证实L-THP抑制〓摄取，促进〓释放，降低细胞内的〓含量；单通道水平的研究证实，L-THP减少豚鼠心室肌单细胞内向钙电流，且具有剂量，电压，频率依赖性，其作用易于洗脱，药物剂量与Ica也具有高度相关性（相关系数r为-0.87）；L-THP还可抑制ISO损伤心肌组织所致的丙二醛含量增加，增加谷胱甘肽过氧化物酶的量，使组织细胞免受损伤。L-THP阻断L-型〓通道，抑制〓的摄取，促进〓的释放，降低细胞内〓含量L-THP作用的离子基础。

Using this method,we discussed for generalized Burger equation with variable coefficients and linear danping,obtained its symmetry group,simliar reduced equations,infinitesimal generator and Lie algebras;In chapter 6,using the Exp-function method,the generalized solutions of combined KdV-mKdV equation with variable coefficients are discussed.

首先介绍了Lie群分析法的基本思想，其次用Lie群分析法得到了带线性阻尼项的变系数广义Burgers方程的无穷小变换、无穷小算子的李代数结构，并具体求出了带线性阻尼项的变系数广义Burger方程的群不变解和约化方程。

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。