边界值问题

The main work and the originality points of this dissertation could be concluded as the following parts:(1) To analyze systematically the mathematical model of LES of air flow in great space, under the case of isothermal and non-isothermal, as well as the combined action of buoyancy and strain. Some basic problems are studied about the LES application into airflow simulation of great space, such as boundary conditions, spatial difference scheme and time advancing scheme, time step etc., which creates the basis for the LES application to indoor airflow simulation.(2) Both the instantaneous and time averaged flow field of great space with multiple jets under isothermal and non-isothermal cases are explored with large eddy simulation method, and also discussed the dynamic characteristics and the law of fluidflow in the great space.(3) Based on the results of LES of the great space and the Fanger thermal comfort indexes, it is brought forward the concept of the series of dynamic thermal comfort evaluating indexes, which could be divided into thermal comfort index with time averaged properties PD, PPD, PMV, thermal comfort index with instantaneous properties IPD, IPPD, IPMV, and time averaged thermal comfort indexes TAPD, TAPPD, TAPMV, and transient situations time averaged thermal comfort indexes TTAPD, TTAPPD, TTAPMV. The differences among them and the calculation methods are discussed, and the four kinds of indexes are calculated with the thermal comfort index PD as an example.(4) Based on the LES results it is discussed the hot air stratification phenomena in air-conditioned buildings in the case with air supply and return registers on the ceiling and the case on the sidewall. The fundamentals of the hot air stratification are studied and the relations of estimating hot air stratification are brought forward.(5) With the advanced apparatus such as hot wire film anemometer IFA300 and laser particle field anemoscope, corresponding model test and site measurements have been done, which are compared with the simulation results and LES is proved a very promising method in air flow simulation indoor.

本文主要工作既创新点体现在以下几个方面：(1)系统分析了等温、非等温和考虑剪切力与浮升力综合作用的高大空间大涡模拟数学模型，并研究了高大空间大涡模拟在室内气流仿真应用中的一些基本问题，如边界条件、空间离散格式和时间推进格式、时间步长选择等问题，为大涡模拟在室内气流计算中的广泛应用打下了基础；(2)首次用大涡模拟方法研究了高雷诺数下高大空间多射流在等温、非等温情况下的瞬时流场和时均流场分布，并探讨了多射流流场的动态特性和流动规律；(3)基于大涡模拟的动态仿真结果和Fanger的热舒适指标，首次系统地提出了动态热舒适评价指标体系的概念：即基于时间平均参数的热舒适指标PD、PPD、PMV；基于瞬时参数的瞬时热指标IPD、IPPD、IPMV；基于时间平均热舒适指标TAPD、TAPPD、TAPMV；以及沿行动迹线的时间平均热舒适指标TTAPD、TTAPPD、TTAPMV，并分析了四类热舒适指标的差异性和计算方法，还以PD值为例对四类指标分别进行了计算；(4)基于数十种工况下空调房间大涡模拟的结果，研究了空调建筑上送上回和侧送侧回两种情况下热分层现象，并探讨了热分层的基本规律，首次提出了避免热分层现象的判断公式；(5)在暖通空调领域，首次使用IFA300热线风速仪、激光粒子速度场仪等先进设备，完成了与大涡模拟相对应的模型试验，并把实测结果与仿真结果进行了对比，说明LES在室内气流仿真方面是一种很有前景的方法。

Due to the restriction of computational complication and precision,WRM boundary collocation method can only be used to simulate temperature fields of single-particle model,as for the case of some more complicated particle geometry shape it is very hard to obtain sufficient approximation solutions.Thus,BEM is adopted to analyze the thermal conduction problem of composites with particle of arbitrary geometry.

由于受计算复杂程度和计算精度的限制，采用加权残值法只能分析单夹杂问题，且对于更复杂的夹杂形状很难得到良好的近似解，因此接下来采用边界元方法分析了具有任意形状夹杂复合材料的温度场问题。

The proposed method has the merit that the numerical characteristics of stochastic temperature field response can be obtained by analyzing the random temperature field just in one time.3. Perturbed numerical algorithm of nonprobabilistic convex set theoretical models on the temperature fieldThe uncertain parameters of physical parameters and initial boundary conditions of heat conduction are described by the convex model. The perturbation formulas of the upper and lower bounds of temperature field response with unknown-but-bounded parameters are given via the combination of matrix perturbation theory and the convex set theory model.4. Numerical analysis for transient temperature field with interval parametersConsidering the uncertainties of the transient heat transfer, the physical parameters and initial boundary conditions are regarded as interval variables.

该方法具有只进行一次随机温度场分析便可以获得其响应的数字特征的优点。3、温度场的非概率凸集合理论模型的摄动数值解法将结构导热的物理参数、温度场的初始和边界条件等不确定性参数以凸模型加以描述，基于矩阵摄动理论和处理不确定问题的凸集合理论模型的结合，导出有界不确定参数瞬态温度场响应所在集合的上、下界摄动计算公式。4、具有区间参数的瞬态温度场数值分析考虑结构瞬态热传导问题的不确定性，将结构各物理参数和温度的初、边值条件均视为区间变量。

A direct method is implemented for computing the free-term coefficient and the Cauchy principal value integral in the higher-order boundary element method for potential flow.

采用直接数值计算方法计算了势流问题高阶边界元方法中的自由项系数和柯西主值积分，建立了波浪与结构物作用的一种高阶边界元方法。

First, it was to obtain two binary images from segmenting image by two thresholds. Second, erosion, opening and closing were done to the two images according to some knowledge of the shape and location of the objects in the image that we have already known. Last, the edge information from the image segmented by a high threshold was put into the image segmented by a low threshold. It is the way to segment and discern circular objects accurately from the complex image and can greatly improve the accuracy rate of discerning.

首先分别根据两个阈值进行分割得到两幅二值图像，然后根据目标是圆形以及其大致位置等先验知识分别对两幅图进行腐蚀，开启，闭合等数学形态学运算，将高阈值分割得到的图像中的边界信息叠加到低阈值分割得到的图像中，实现对复杂背景图像中圆形物体的准确分割与提取，解决了复杂背景图像中物体识别率低的问题。

Using the concept of the of weighted residual method and choosing the fifth B-spline as a trial function to meet the needs of boundary conditions,the mechanical problem of large deflection of a rectangular thin plate is discussed.

采用加权残值法探讨大挠度力学问题时，用5次B样条作为未知函数的试函数，使其直接满足边界条件，这种方法与传统的有限元法相比，具有未知量少，自由度少，连续性强，边界条件容易满足等优点

In this problem, the main difficulty is that the variation of border electric potential is not sensitive to the variation of conductivity in the field. So far, there is not an effective method to solve the problem.

在低频电流场逆问题的计算中，最大的问题在于边界电位值的变化对场域内部电导率的变化不敏感，到目前为此，对此问题还没有一个公认的有效的解决办法。

The empirical mode decomposition method is introduced to extract the trend item of gyro's drift, but the local mean estimation isn't precision and the end effects exist in the conventional EMD method. The two-tap adaptive time-varying filter and the adaptive border estimation are used to modify the EMD. After the trend extraction, the method of time series analysis is used to make the autoregressive moving average model for stationary time series.

根据陀螺漂移的特性，提出采用经验模分解的方法对其趋势项进行提取，但传统的经验模分解方法存在局部均值估值不准，插值过程存在端点效应的问题，因此，本文又引入二拍自适应滤波及自适应边界估值来对原方法加以改进；在成功提取趋势项后，通过采用时间序列的分析方法，建立了陀螺漂移平稳时间序列的自回归滑动平均模型；并得出陀螺漂移模型可近似为常值加一阶马尔可夫过程这样一个结论。

For solving the boundary case of 〓 interpolation subdivision given in forth chapter, we give convergence and smoothing conditions and a C〓 continuous four point interpolation scheme using the curve triple subdivision methods from chapter three.

另外本文在第三章给出了曲线三分法细分算法的收敛和光滑条件，并给出了C〓连续的三分法四点插值算法，它解决了我们第四章给出的〓插值算法在边界上会遇到的问题。

This paper addresses a new boundary detection algorithm called BORAL (Boundary Points Detector Based on Angle),according to the problem of low efficient boundary detection and that it is uneasy to determine the scope of the parameter pruning in data mining.

针对目前数据挖掘中边界点检测效率低、参数阈值范围不容易确定的问题，提出一种新的边界点检测算法BORAL。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。