计算
- 与 计算 相关的网络例句 [注:此内容来源于网络,仅供参考]
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As we all know, In order to adapt to the needs of national economic constructions,To solve the problem of river traning in the land management,the computation of water conveyance losses in the water conservacy constrution,the flood computaton in the Flood Prevention,the Hydrological Computation when bridge design of bridge in the highway and railway constructions, and the roughness of the river channel is a important parameter in the Hydraulic calculation, many scholars commtted to the roughness of the river floods.
为了适应国民经济建设的需要,解决国土整治中的河道治理,水利建设中的输水损失计算,洪水计算,公路、铁道建设中的桥梁设计都涉及到水力计算,其中糙率是水力计算中的重要参数,很多学者致力于河流洪水糙率的研究。
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The horizontal and vertical first derivatives of magnetic anomalies of an infinite cylinder are calculated by the cosine transform method, in which the maximum errors are -0.28 nT/m and 0.47nT/m, respectively and the percent errors are generally within -3.57%~3.27% and -1.94%~1.88%, respectively except several data of the boundary and part are bigger because of remains of Gibbus effect. The calculating curve and theoretical curve are approximately coincident, and there is no influence by effective magnetic dip angle in computing. But the errors with the Fourier transform method are -10.62nT/m and 14.42nT/m, there is large departure between the calculating curve and theoretical curve and evident influence by effective magnetic dip angle in computing.
利用余弦变换法计算的无限长水平圆柱体磁异常水平和垂向一阶导数的最大误差分别为-0.28nT/m、0.47nT/m;水平一阶导数的误差一般在-3.57%~3.27%之间,垂向一阶导数的误差一般在-1.94%~1.88%之间;计算的磁异常一阶导数值与理论值大致重合,而且不受有效磁化倾角的影响而Fourier变换法计算的水平和垂向一阶导数最大误差分别为-10.62nT/m、14.42nT/m,计算曲线与理论曲线偏离大,受磁化倾角的影响也较大。
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Firstly, on the basis of summarizing the research results, this paper deeply discusses the calculating model to analyze the instantaneous motion state in vehicle collision and the interrelation between restitution coefficient and vehicle collision speed. The simplified Gim tyre model is introduced, this type model has the fast computing and higher calculating precision, it is the practical vehicle type model in the analysis of vehicle collision accident at present. According to the collinear collision and two-dimension collision, the paper establishes the impact model at vehicle collision moment and the post collision movement model.
本文在总结前人研究的基础上,分析了车对车碰撞作用瞬间状态的计算模型及碰撞恢复系数与碰撞前、后速度的关系:介绍了Gim轮胎理论模型的简化形式,该模型计算速度快、计算精度高,尤其在车轮大侧偏角运动时其计算精度远远优于其它轮胎模型,是目前在汽车碰撞事故分析中最为实用的汽车轮胎理论模型:根据交通事故中最普遍的一维碰撞和二维碰撞的不同情况,分别建立了碰撞作用瞬间的力学模型和碰撞后车辆动力学模型。
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How to calculate precisely the circumstance function matrix for the gimbaled system is lucubrated. The method of using exterior data and the method of calculating iteratively are put forward. The simulation result shows that two methods can increase the calculating accuracy of the circumstance function matrix.
讨论了平台式系统环境函数矩阵的精确计算问题,提出了利用外测数据与应用迭代技术精确计算环境函数矩阵的方法,仿真计算表明,这两种方法能够有效提高环境函数的计算精度。
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In this paper,a three dimensional elastic plastic hydrodynamical numerical method and the code MEPH3D using this method which can be used on high speed impact problems are introduced.
介绍一种可用于高速碰撞问题数值模拟的三维弹塑性流体动力学数值计算方法,以及应用该方法研制的应用软件MEPH3D,并给出了一些高速碰撞问题的数值计算结果,计算结果表明该程序具有计算三维高速碰撞问题的能力。
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Using three dimensional inharmonic element and the modified subspace iteration scheme for calculating dynamic characteristic of the shear wall, and using plane stress element and Newmark and Newton-Raphson method for calculation of seismic behaviors of shear wall under earthquake loads.
采用三维非协调实体元及改进子空间迭代方法计算剪力墙的特征对;采用平面应力单元并利用Newmark法与Newton-Raphson法相结合的方法计算剪力墙在地震荷载下的地震反应,并用FORTRAN77(F90)语言编制了相应的计算程序和前后处理程序,经计算验证程序是有效的。
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In this paper, the generator model of constant transient voltage and the invariableness impedance model was used, and the saliency of generator is included; through the analysis of the characteristic of the network equation calculation in the transient stability analysis, a new node ordering algorithm is proposed. Better initial value can accelerate the convergence rate of the networking equations, reduce the number of iterations, thus to cut down the amount of calculating time.
本文首先建立了适合于暂态稳定分析的简单模型,其中发电机采用E_q恒定模型,考虑了发电机的暂态凸极效应,负荷采用恒定阻抗模型;研究了电力系统的暂态稳定分析方法,指出目前数值积分暂态稳定计算方法中存在的不足,主要是网络方程的求解速度过慢;分析了暂态稳定计算中网络方程的特点,将稀疏技术应用于网络方程的求解,提出了一种新的节点编号方法——最小度最小有源节点道路集算法,减少了网络方程的计算量;在进行交替迭代求解时,将预测算法应用于每一积分步网络方程功角和电压的初值估计当中,应用自回归算法和广义延拓算法,期望给出一个更有效的电压和功角初值方案,来加快方程的收敛过程,减少方程迭代的次数,以提高计算速度。
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For this problem, finite element method based on deep shell element( much project practice prove veracious) is taken to calculate SCF and compared with the results of the method KAW、DNV and EFT.
针对这一问题,利用基于厚壳元的有限元法(大量工程实践检验结果表明该方法计算结果相对准确)对K型管节点的应力集中系数进行了计算,并将计算结果与KAW、DNV及EFT法计算结果进行了对比分析。
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For some rock slopes, which have not distinct failure surface, but have complicated structure or load on the top and so on, a stability analysis of this type slopes by finite element method is presented, the failure surface is defined by certain rule or strain zone from the computed model, and then the safety factor of the rock slope is abtained by finite element method and limit equilibrium methodAt last, using ANSYS , a famous commercial finite element analysis software, a example of high-steep slope which is bearing the load of the LongGe Mansion is presented, the stability of this slope is studied, as a paradign the the stability evalution of complicated high-steep slope under the action of load of building , the chapter gives some meritable reference in stability assessment of rock slopes using numerical simulation by three-dimension elastic-plastic finite element.
并用有限单元法建立边坡的具体模型,应用折减边坡岩体参数、逐级施加荷载等与边坡工作环境相似的方法进行模拟计算,根据计算结果,采用一定的判别准则或图形可视化方法,确定出边坡的滑裂面,再采用刚体极限平衡法或有限单元法计算其安全系数;最后,通过某一工程实例,用大型有限元程序对边坡在建筑物荷载作用下的稳定性进行分析研究,并以此作为计算分析复杂高边坡在高层建筑物作用下的稳定性评价的一个范例,在采用有限元弹塑性数值模拟岩质边坡稳定性方面提供一些有价值的参考。
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Density Functional Theory method was used to optimize the geometries of 209 PCDE molecules, 209 PBDE molecules and 75 PCDD molecules at the B3LYP/6-31G* level. Using computed structural parameters as theoretical descriptors, the forward stepwise multiple regression technique was adopted to obtain QSPR models of environmental partition properties for these POPs by using GQSARF 2.0 and SPSS12.0 for windows programs. The obtained QSPR models are as follows:(1) QSPR models for predicting subcooled liquid vapor pressure, n-octanol/water partition coefficients lgK_(ow and subcooled liquid water solubilities -lgS_(w,l of PCDEs, of which correlative coefficients (R~2) are 0.988, 0.958 and 0.959 and the root-mean-square-error of estimation are 0.134, 0.116 and 0.327 respectively.(2) QSPR models of lgPL and n-octanol/air partition coefficients lgK_(oa for PBDEs, which both contain three structural parameters. The values of R2 for the two models are both 0.997 while the values of RMSEE are 0.073 and 0.062 respectively.(3) QSPR models of lgKow and–lgS_ for PCDEs, which both have one variable (mean molecular polarizability,α). The values of R~2 for the two models are 0.978 and 0.866 and the values of RMSEE are 0.300 and 0.270 respectively.(4) The molecular structures of 24 substituted naphthaline compounds were optimized using Hartree-Fock and DFT methods at four different levels and the same means was used to obtain four three-parameter (EHOMO, q~+ andα) QSPR models of lgK_. The model at the HF/6-311G** level is the best one of which R2 is 0.9662 and RMSEE is 0.380.(5) QSPR study for environmental partition properties of PCDEs was also performed using position of Cl substitution method in which simple parameters of substitution position were taken as descriptors. The multiple linear regression was performed with GQSARF 2.0 and SSPS 12.0 for windows programs to obtain QSPR models of lgP_L, lgK_ and–lgS_ for PCDEs of which R~2 are 0.991, 0.983 and 0.965 and RMSEE are 0.311, 0.100 and 0.300 respectively.
采用密度泛函理论方法在B3LYP/6-31G*水平上对PCDEs、PBDEs和PCDDs的分子结构进行了全优化计算,以计算得到的量子化学参数作为理论描述符,采用GQSARF 2.0和SPSS 12.0 for windows统计程序进行正向逐步回归分析,建立了这些POPs的环境分配性质的QSPR模型:(1) PCDEs的过冷液体蒸汽压、正辛醇/水分配系数lgK_(ow和水溶解度-lgS_(w,l的QSPR模型,这3个QSPR模型的相关系数(R2)分别为0.988、0.958和0.959,估计的均方根误差分别为0.134、0.116和0.327;(2) PBDEs的lgPL和正辛醇/空气分配系数lgK_(oa的QSPR模型,这两个模型都包含三个分子结构参数,其R~2都为0.997,RSMEE分别为0.073和0.062;(3) PCDDs类化合物的lgK_和-lgS_w的QSPR模型,两个模型都只含一个变量,其R~2分别为0.978和0.866,RSMEE分别为0.300和0.270;(4)采用Hartree-Fock和DFT方法,在4种不同水平上优化计算了24个取代萘系列化合物的分子结构,采用上述同样的方法分别建立了四种水平上的三变量lgK_模型,通过比较得到,在HF/6-311G**水平计算得到的模型最好,R为0.966,RSMEE为0.380;(5)同时,采用氯原子取代位置方法对PCDEs的环境分配性质进行QSPR研究,建立了PCDEs的lgPL、lgK_和-lgS_的QSPR模型,其R~2分别为0.991、0.983和0.965,RSMEE分别为0.110、0.100和0.300。
- 推荐网络例句
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The split between the two groups can hardly be papered over.
这两个团体间的分歧难以掩饰。
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This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.
这种做法不仅鼓励了更多的反应,而且减少跟风的可能性。
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The new PS20 solar power tower collected sunlight through mirrors known as "heliostats" to produce steam that is converted into electricity by a turbine in Sanlucar la Mayor, Spain, Wednesday.
聚光:照片上是建在西班牙桑路卡拉马尤城的一座新型PS20塔式太阳能电站。被称为&日光反射装置&的镜子将太阳光反射到主塔,然后用聚集的热量产生蒸汽进而通过涡轮机转化为电力