模拟的

Investigation on the relationship between flow pattern and air age.

室内空气流动数值模拟的风口模型综述。暖通空调，2000，30（5）：33－37

John Moore and FitzHugh started by planning how to programm an analog computer which could be used to solve the Hodgkin-Huxley equations .

约翰摩尔和菲茨休开始规划如何通过一个模拟的计算机程序可用于解决霍奇金，赫胥黎方程。

Most computer screens are analog.

大多数计算机屏幕是模拟的。

The regulation of gene expression is to have relations to the assembly of the DNA binding proteins which bind to DNA to initiate the transcription. Some of these proteins have the ability to promote bending or looping of DNA. The FIS protein regulates gene expression in Escherichia coli by this property of bending DNA. There are many researches to discover the mechanism of FIS protein binds to DNA. However the experiment data only show the supposititious results and figure out the model of FIS-DNA complex structure. This research uses molecular dynamics simulation to compute the detail of the interaction between FIS and DNA. We observed FIS prominently affects the DNA bending by the type of local bending. Analyzing the DNA structure properties, roll and slide, also demonstrates the local bending type and region. The hydrogen bonds between FIS and DNA are analyzed to compare with the experiment data. Finally we compute the binding free energy between FIS and DNA to estimate the result of simulation and compare with the value of λ-repressor-DNA complex.

基因的表现与结合於DNA促使DNA转录作用起始的DNA结合蛋白组装有关，一些这类的蛋白质具有促使DNA扭曲或将DNA形成环状的能力，FIS蛋白质即是藉由扭曲DNA的特性调控大肠杆菌基因的表现，目前已有很多的研究发现FIS与DNA结合的机转，然而这些实验的数据仅能显示推测性的结果，进而利用这些结果推论出FIS与DNA聚合体结构的模型，本研究利用分子动态模拟的方式计算FIS与DNA交互作用的细节，我们观察到FIS主要影响DNA的扭曲方式为DNA区域扭曲的类型，并且分析DNA结构特性roll与slide也指出扭曲方式为区域扭曲与其扭曲的区域，我们也分析FIS与DNA之间的氢键，并且与实验的资料作比较，最后我们计算FIS与DNA之间的结合自由能评估模拟的结果，并且计算出的值和λ-repressor与DNA聚合体结构的实验值作比较。

The quantity computed is the expected clutter power at the output of any specified range gate by the method of integrating reflected energy between constant Doppler loci in range-gate circles with a model of sum and difference antenna gain pattern for APAR. Base on the analyzing of APAR terrain clutter spectrum, Rayleigh, Correlated Log-Normal and Weibull distribution terrain clutter of APAR general pulse signal was simulated with the method of zero memory nolinearity transform.④The Doppler frequency of target echo is simulated on video frequency in this dissertation.

该软件采用了用C语言建立框架结构，而在程序高重复部分和有运算速度要求的地方，用汇编语言编写具有高并行能力程序的方法，不仅满足了系统高运算速度和实时性的要求，也使得软件系统结构模块化，代码具有良好的维护性和重用性；③对机载相控阵雷达HPRF、MPRF的和、差通道地面杂波功率谱进行了较为全面的研究，通过建立由四个子波束构成的机载相控阵雷达杂波和差波束天线方向图数学模型，选取体现高度线杂波的修正的地面后向散射模型，以载机平飞为例，采用沿距离门——等多普勒线区域积分的方法，得到了杂波功率谱，并利用零记忆非线性变换法实现了机载相控阵雷达常规脉冲情况下瑞利分布、对数正态分布和韦布尔分布地面杂波的模拟；④提出了采用在视频上对目标回波的多普勒频率进行模拟的方法。

In this paper, the stress and strain fields of lithosphere in Himalayan Western Syntaxis orogenic belt and its adjacent areas since 10Ma are investigated through using the 3-D finite-element simulation, and deformation and evolution process in former 2Ma are simulated with different rheological parameters and rheological structure. Studies on functions in simulation process of different viscosity parameters, constitutive relation and changes of initial curst thickness show below results:(1) When various viscoelastic models are adopted, the selection of the coefficient of viscosity in the Western Syntaxis area has important influence on the its uplifts and evolutions. The computational results show that the viscosity in the Western Syntaxis area should be smaller than 1023Pa·s;(2) When the elastic model is adopted in relatively rigid Tarim basin, obvious changes are induced to the stress and strain fields of the whole Western Syntaxis area;(3) The existence of mechanical property stable block doesn′t make the propagation of the stress field show obvious decoupling phenomenon.

用数值模拟的方法探讨了自10 Ma以来喜马拉雅弧形造山带的西构造结及邻区岩石圈的形变和位移变化特征，并采用不同的流变参数和流变结构模拟了前2 Ma内的形变和应力场的演化过程，通过对不同黏性系数、本构关系和初始地壳厚度的改变在演化过程中所起的作用研究表明：（1）采用黏弹性模型时，西构造结区黏性参数的选取对西构造结及邻区隆升高度和隆升范围有重要影响，计算结果给出西构造结区地壳黏性系数应小于1023Pa·s；（2）相对刚性的塔里木盆地采用弹性结构时，对整个西构造结区域的应力和应变场均能引致明显变化；（3）力学性质稳定块体的存在并没有使应力场的传播出现明显的解耦现象。

This paper using the FEM software Marc, for the 50 and 60 degree V groove of flat plate butt joint simulate the one-layer and three layers welding, finish each welding and cooling it down to room-temperature then start the next welding true represent process and get the temperature field, residual deformation and welding residual stress, according to the theory analysis and empirical equation verified the temperature field and residual deformation all correct, comparison with experiment verified the welding residual stress regularity and correctly.

本文利用有限元软件Marc，对开60°和50°V型坡口的平板对接接头，动态的模拟了单层单道打底焊，焊完一道后让试件冷却到室温以及单层单道满焊，每焊完一道后让试件冷却，然后再焊下一焊道，道间温度≤200℃，在以此为初始边界条件下开始下一道的焊接，真实的再现了焊接过程，得出了温度场，残余变形和残余应力场的分布规律，根据理论分析及经验公式验证了温度场以及残余变形的正确性，角变形的大小，这些结果与数值计算相吻合。通过与实验测得的残余应力进行比较，验证了焊接残余应力的分布规律及模拟的正确性。

Simultaneously, the exports of ionization rate and nonionzed concentration are set up as a powerful tool for studying thoroughly the freeze-out effect. dN〓/dp and dN〓/dn are neglected in the linearized equation system of the iteration methods of Newton and Gummel, due to having lower 15 orders or more than dN〓/dn and dN〓/dp, thus the computing effort is cut down with no effect on precision. A new cut-off technique is adopted to accelerate the convergence speed, about twice reduced for Newton iteration method and six times or so for Gummel iteration method. The approximate formulae of Fermi-Dirac statistics are also put forward with simpler form and higher precision. 3. A term dependent on time is added to the electron and hole current succession equations respectively. It is only this model that conservation of charge in transient analysis and alternating small-signal analysis at low temperature can be kept by. 4. The performance of SE-PISCES is explained by the simulation example of PISCES-2B, diode.

研究了低温半导体器件模拟的数值方法：对载流子浓度进行了新的归一化；编制了不考虑掺杂所引进的内建电场时的电离率计算程序；由于低温杂质电离率随偏压状态而变化，为此编制了每次求解迭代时的电离浓度计算程序，并将其插入到求解迭代程序中；同时，设置了杂质电离率和未电离杂质浓度的出口点，为更深入地研究冻析效应提供了有力工具；在Newton迭代法和Gummel迭代法的线性化方程组中忽略了dN〓/dp、dN〓/dn，是因为它们比dN〓/dn、dN〓/dp低15个数量级以上，这样减小了计算量又不影响模拟精度；对Newton迭代法和Gummel迭代法采取了新的截断技术，提高了收敛速度，Newton法迭代法和两次左右，Gummel法减少六次左右；给出了表达式更简单而精度更高的Fermi-Dirac积分近似计算公式。

The main contents and results of research in this paper are shown as following: It is important to built the motion model of a virtual system. As the virtual object is the submarine in this simulation system, we studied on the motion model of the submarine and gave the submarine six DOF space motion equation MultiGen-Paradigm corporation's modeling software named Creator is used, the modeling of all entities and 3D terrain in virtual ocean environment is accomplished. Then introduced the theory of Large Area Database Management and realized the Large area database management; In the course of 3D scene simulation, Vega is utilized to develop the project. The building of 3D scene is done, which includes the simulation of static and dynamic ocean surface, realization of ocean wave, simulation of bow wave and stern wake, utilization of lighting and material, simulation of cloud and fog, kinematics' modeling of submarine etc.

论文的主要研究工作和成果包括以下一些内容：建立虚拟对象的运动模型是构造一个虚拟系统的关键所在，建立的运动模型准确与否直接关系仿真对象模拟的逼真度，由于本仿真系统的虚拟对象是潜艇，所以对潜艇的运动模型进行了研究，给出潜艇空间六自由度运动方程；利用MultiGen-Paradigm公司的Creator建模软件完成虚拟海洋环境中个实体模型建模和三维海底地形模型的建模；然后介绍了大地形数据库管理(LADBM，Large Area Database Management)技术的基本原理，实现大地形数据库管理；在三维场景仿真中，使用Vega驱动软件进行软件开发，完成了三维场景空间的建立，主要包括动态和静态海洋的仿真、海浪、船首波浪和传尾尾迹的实现，灯光和材质的使用，云和雾的模拟等。

In comparison with the observations derived from NOAA AVHRR, under the framework of NCAR CLM3, SCF schemes like CLM3 default, Douville1995, and Roesch 2001 underestimate SCF over vast areas, snow lines simulated in these three schemes are located to the south of that in the AVHRR observation, especially in autumn when snow pack begins to establish; Wu2004 scheme also underestimates SCF in the Eurasian continent in autumn; Yang1997 scheme slightly overestimates SCF, especially along the southern border of the snow covered area; Niu2007 scheme which accounts for the seasonal variation of snow density overcomes the positive bias of SCF simulated by Yang1997 scheme to some extent.

结果表明，在NCAR CLM3的物理过程框架之下，CLM3、Douville1995、Roesch2001三种方案低估了广大地区的积雪覆盖率，模拟的雪线位置偏北，尤其是在秋季积雪初期；Wu2004方案低估了秋季欧亚大陆的积雪覆盖率；Yang1997方案模拟的积雪覆盖率有些偏高，尤其是在积雪覆盖区的南部边缘；考虑积雪密度变化的Niu2007方案一定程度上克服了Yang1997方案的正偏差。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。