求解

An extended hyperbolic mild-slope equation, which can take such terms as wind input, bottom friction and nonlinearity of wave into account, here has been deduced into a parabolic one in the form of a series of governing equations described with complex amplitude. It became a complete wave model when integrated with corresponding physical and imaginary boundaries, and can be solved through the improved Crank-Nicholson or the well known Alternating Direction Implicit difference method, both of which can accelerate the convergent speed , expand limitation of the mathematical method and improve the quality of the solution.

本文基于综合考虑底摩阻、风能输入及非线性影响的推广双曲型缓坡方程，将其进行转换，产生一个演变方程，其复振幅控制方程为抛物线性，并采用ADI差分格式、改进的Crank-Nicholson格式及相应的物理和虚拟边界条件进行求解，以提高数值模拟的适用性、数值计算的稳定性、收敛速度及精度。

The alternating group iterative method for the dispersive equation with periodic boundary condition is presented.

给出了求解具有周期边界条件色散方程近似解的交替分组迭代法。

The alternating group iterative method is used to solve the implicit scheme and the Crank-Nicolson scheme of the dispersive equation.

数值试验对色散方程的隐格式与Crank-Nicolson格式分别应用交替分组迭代求解。

For accelerating this problem's compute time in parallel computer, we use Saul'yev type asymmetric different scheme and classicality explicit-implicit type to get a new alternating group explicit method for solving diffusion equation.

为便于在并行计算机上计算以加快计算速度，现将第二类saul'yev非对称格式以及古典显、隐式相结合，构造了求解扩散方程的一类交替分组显格式，其基本结构为四点组，并针对内点为偶数的情况，在节点两端点处进行了处理，以提高精度。

By using the Solver Add-in included with Microsoft Excel the optimum solution is identified and can then be manually adjusted to test alternative scenarios.

利用求解增益集，包括与Microsoft Excel的最佳解决方案是确定的，其后也可以手动调整，以测试的其他情况。

However, these methods are only an amalgamation of some techniques, which are dispersive, unsystematically and not general.

但这些方法仅仅是一些求解技巧的融合，而且是分散的、不系统的、不具有普适性。

Compared with traditional numerical methods, the LB method has several important features, including: simplicity in algorithm, easily programming, direct calculation of pressure from a state equation and amenability to simulate all kinds of flow field with complex boundaries, it also has many advantages in the respect of parallel computation because of its regional evolution.

与传统的计算方法相比较，LB方法具有算法简单、编程容易、压力可以通过状态方程直接求解、能够模拟各种复杂边界的流场等优点，并且计算的局域性使其在并行计算方面也具有很大的优势。

Compared with traditional numerical methods such as the FEM, FDM, etc, the LB method has several important features, including: simplicity in algorithm, easily programming, direct calculation of pressure from a state equation and amenability to simulate all kinds of flow field with complex boundaries, it also has much advantage in the respect of parallel computation because of its regional evolution.

与传统的计算方法如FEM、FDM等相比，LB方法具有算法简单、编程容易、压力可以通过状态方程直接求解、能够模拟各种复杂边界的流场等优点，并且计算的局域性使其在并行计算方面也具有很大的优势。

This paper raises an objection to the method of gettinS special points on the intersection curve by using analytic geometry and graphic method.

而在求解这一系列公共点的过程中，较准确和方便地求出控制相贯线形状和位置的特殊点的问题，尤为突出。

The basic approach of protecting people from being hurt or killed in an accident is to improve crashworthiness of vehicles. This paper starts with discussing theories and methods for vehicle passive safety design, which included experiential methods, analytic methods, multi-body dynamics methods, crash test methods and the finite element method. Emphasis will be paid to the basic FEM theories and algorithms of impact problems. Topics discussed include the governing equation, element discretization, hourglass control, time integration, material model, shell element algorithms and contact-impact algorithms. For more reliable simulation results, this paper then conducts study on how to accurately get material model parameters by combining the FEM method with experimental method, and develops relevant material test machine and parameter calculating software. Based on that, basic typical impact simulation and test validation study are conducted. On the basis of the above work, the paper studies the thin-shell structures'crashworthiness, which was affected by the following factors: spot-weld features, shell thickness, cross-section and pre-deformation. As to vehicle parts'crashworthiness, the paper conducts simulation study of designing energy-absorbing steering system and adaptive airbag system. A practical energy-absorbing steering wheel is designed as an example. In further depth research, the paper suggests several inverse quantificational methods for vehicle crashworthiness design based on the ideal crash characteristics. The above theories and methods are applied with good results through several practical vehicles' crashworthiness design and improvement.

文中对汽车碰撞安全性的设计理论和方法进行了归类和总结，其中包括经验法、解析法、多刚体动力学法、试验法以及有限元方法等；重点介绍了碰撞有限元法的基本理论和有关算法，涉及到有限元求解控制方程、单元离散、沙漏模态控制、时间积分、材料模型和应力修正、薄壳单元算法以及接触碰撞界面算法等，探讨了有限元计算中的材料模型参数获取技术，开发了相应的材料试验装置及材料模型参数反求软件，在此基础上进行了基本的碰撞仿真算例和试验对比研究；文中通过应用有限元方法研究了薄壁构件的碰撞吸能特性，指出了设计薄壁吸能构件时需要考虑的几个主要影响因素，即焊点、壁厚、横截面和预变形等；在关于车辆部件的碰撞安全性能设计中进行了吸能转向机构和自适应安全气囊的仿真研究，提出了吸能转向机构和自适应安全气囊的仿真研究方法；文中最后探讨了整车碰撞性能的设计与改进方法，提出了以理想碰撞特性为目标，采用分段加速度或者根据碰撞时间进行设计的反推设计法、部件吸能仿真优化设计法等量化设计方法，并通过综合应用文中所讨论的相关技术进行了整车碰撞性能的设计与改进实例研究，所选定的车型是大众化的普通轿车和碰撞安全性基础较差的微型面包车，研究结果表明，本文所提出的设计与改进方法是适用而有效的，具有重要的工程实用意义和价值。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。