| 1. | Computational accuracy of equivalent magnetic charge method is high , but its calculation is complicated
等效磁荷法计算精度高，但计算过程相对复杂。 |
| 2. | ( 4 ) to raise the computational accuracy and efficiency , we have designed a self - adaptive space grid that can guarantee mass conservation and energy conservation , and have also developed the techniques for the time stepsize automatically varying
( 4 )设计了保持质量和能量守恒的自适应空间网格，发展了自动改变时间步长的技术，使之能够更好地保证计算精度，提高计算效率。 |
| 3. | The main goal of this paper is to make a thorough research for the nine - point difference scheme , make clear its advantages and disadvantages , and improve it in view to its main disadvantages to raise the computational accuracy , speed and efficiency
本文致力于对九点差分格式作较为彻底的研究，弄清其优、缺点，并针对其主要缺点作出改进，以进一步提高整个计算的精度、速度和效率。 |
| 4. | Equivalent circuit method is usually used before . this method has apparent defect , that is , the ignorance of higher order mode effect , which can greatly affect the computational accuracy . in cases that require high accuracy , this method is unusable
以前一般采用等效电路法分析和设计脊波导元器件；这种方法的缺点比较明显，那就是对高次模的影响不加考虑，使得计算精度大受影响，在较高要求的场合甚至完全不可用。 |
| 5. | Aiming at higher computational accuracy , the unstructured hybrid mesh and the distributed parallel computation are used in 3d complex flow field simulation , the combination of these two techniques often causes difficulties in data structure and sub - domain definition because of the non - unification of mesh elements
在三维复杂外形的流场计算中，为了得到较高的计算效率及保证数值模拟的准确性，经常要采用混合网格及并行计算技术。 |
| 6. | Results show that the aspects are obviously improved in the requires of functional qualities , computational accuracy , convengence and computational speed of algorithms . by this , the new technique of variational data assimilation maybe has wilder application in practice
所得结论表明，与传统的四维变分同化方法相比，本文提出的方法在函数性态要求、计算精度、算法收敛性和计算速度方面有了明显改善，使得变分同化技术有可能更广泛地应用于实际业务。 |
| 7. | As an example , the implementation of the laplace equation with the gridless method has been presented at first and the resulting large scale matrix equations are solved by gmres algorithm . the numerical simulations of the flows over a cylinder are tested successfully with clouds of different scales , which shows the " cloud " effects on the computational accuracy
本文先以代表定常不可压位势绕流的laplace方程为例，研究了laplace方程的无网格离散形式，并运用gmres高效算法对其快速求解，数值模拟了典型的圆柱绕流；并通过不同点云尺度的数值模拟，显示出点云尺度对计算精度的影响。 |
| 8. | The hydrauli c model of gradual dike - break simulates numerically the 2 - d flow of gradual dike - break waves . it shows the variation of flow field on breach , and the complicated flow characteristic of the propagation , diffraction , reflection and deformation of the dike - break waves . the hydraulic model can realistically simulate the burst process of dike , and computational accuracy is satisfied with the engineering demands
本文建立逐渐溃堤的水力模型首次对二维逐渐溃堤波的流动问题进行了数值研究，揭示了逐渐溃堤过程中溃口处流场的变化情况，以及溃堤波的传播、绕射、反射及变形的复杂运动特征，能较好地模拟实际工程中的溃堤失事，模拟比较逼近于真实溃决过程，计算精度可满足工程要求。 |
| 9. | A highly efficient numerical algorithm by using multi - grid method ( mgm ) is introduced to solve the three dimensional field distribution in the present paper . formulae of the restriction and prolongation in mgm computation is deduced , and a 3d program of mgm is accomplished , which can solve the field distributions in electron optical systems for various electrostatic lenses . the 3d field distribution in an electrostatic concentric spherical model is tested with mgm algorithm and an algorithm based on finite difference method ( fdm ) respectively . comparing these two results in view of computational efficiency and computational accuracy , it appears that mgm is superior to fdm in solving electrostatic field distribution for the electron optics problem . this paper shows that the 3d field computation using mgm greatly improves the computational efficiency of field distributions in electron optical systems and shortens the computational time
本文将一种高效率的数值计算方法? ?多重网格法引入三维静电场分布的计算，多重网格法利用限制和延拓可迅速求得满足精度要求的场分布.研究了求解各种静电透镜电子光学系统三维场分布的多重网格法程序，验算了静电同心球模型的三维场分布.通过与目前在场计算中常用的有限差分法进行比较，可以看出多重网格法的计算效率和计算精度优于有限差分法.本文表明利用多重网格法计算三维场大大提高了场分布的计算效率，缩短了计算时间，因此为后续计算打下了良好的基础 |
