查询词典 dirichlet boundary condition

In the last chap-ter,the natural integral equation and natural boundary element method forharmonic problem on exterior elliptic domain are introduced.Then,based onthis,the natural boundary reduction method for a kind of exterior problem ofanisotropic constant coefficients elliptic equation is discussed, the natural inte-gral equation and its solving method on circular boundary and elliptic bound-ary are obtained.These results can be directly applied in coupled methodand DDM for exterior boundary value problem.

最后，讨论了椭圆外区域调和问题的自然积分算子即D-N算子及自然边界元方法，并基于此研究了一类各向异性常系数椭圆型方程外问题的自然边界归化方法，首次得到其在圆周边界及椭圆边界上的自然积分方程及其求解方法，并将这些结果直接应用于外边值问题的耦合算法。

In viewof geological records preserved from different regions of the world are not identical, its suggested that, whencorrelating the Ordovician-Silurian boundary, at the global boundary stratotype section, the FAD of N.persculptus be selected as the biomark, the transgression event identical to the FAD of N. persculptus as theauxiliary physical mark and the mass extinction and chemical anomaly events respectively as the auxiliarybiomark and chemomark. In some regions with few graptolite, the Ordovician-Silurian boundary should beindicated by the auxiliary marks, such as the transgression event, mass extinction or chemical anomaly event,with the other fossil such as conodont nearest to other geological events as the provincial biomark forcorrelation. In other regions with much stratigraphic hiatus originated from the regression, theOrdovician-Silurian boundary should he marked by the regression-transgression event nearly relevant to the N.persculptus Zone.

鉴于不同地区留下的地质记录不完全相同，奥陶／志留系界线对比方法不同：在界线层型剖面上，以N.persculptus的首现为生物标志，以与之基本一致的海侵事件为辅助的物理标志，以生物集群绝灭事件和化学异常事件为辅助的生物和化学标志；在笔石极不发育的地区，则以海侵事件、生物绝灭事件或化学异常事件为辅助标志，以与其相距最近、并且具有区域对比性的其它门类化石作为界线对比的生物标志；对于由于海退事件所造成地层缺失很多的地区，则以海退／海侵事件作为划分界线的物理标志，并以相映的海侵事件的开始作为奥陶／志留系的分界。

Boundary polynomial point interpolation mesh-free method and boundary radial point interpolation mesh-free method were presented, based on polynomial basis and radial basis respectively for transient eddy current analysis, and their interpolation shape functions satisfy the Kronecker delta function and the essential boundary conditions can be directly imposed on the boundary nodes. An example on analyzing transient eddy current of a square metal column was set to prove the validity of the proposed methods, and a comparison on accuracy between BPPIM and BRPIM was analyzed as well.

运用多项式点插值法和径向基点插值法构造形函数，推导了适合于工程电磁场瞬态涡流问题的多项式基点插值边界无单元方法和径向基点播值边界无单元方法，这两种方法的空间插值形函数满足Kronecker delta条件，从而强加边界条件可以直接施加在边界点上，以金属长方柱的瞬态涡流分析作为数值算例，证实了两种方法的正确性和有效性，并对两种基类的点插值法进行了精度分析和比较。

For a given Sturm-Liouville equation with positive leading coefficient function, by use of the monotonicity results of its natural loops, limit of boundary conditions and eigenvalues in the space of self-adjoint boundary conditions, a proof of the equalities among eigenvalues for coupled boundary conditions and those for separated boundary conditions is made.

内蒙古工业大学理学院副教授 2。对于给定的首相系数函数为正的 Sturm-Liouville方程，利用在自伴边界条件空间上自然圈、边界条件的极限和特征值的单调性的几个结果，给出了在偶合边界条件与分离边界条件下的特征值间的一些等式的证明。

Lakatos'the principle of tolerance led to blurring of boundary line about progressive and deteriorative research program, mistiness of boundary line of reasonable and unreasonable research program. His standard of demarcation led to obscuring the boundary line of science and non science. His principle of theory of error made boundary line of right and wrong theory, ture and false theory blurred.

拉卡托斯的宽容原则导致进步的研究纲领和退步的研究纲领，合理的研究纲领和不合理的研究纲领之间的界线模糊；他的划界标准使科学与非科学之间的界线模糊；他的可错主义原则使正确的理论和错误的理论，真的理论和假的理论之间的界线模糊。

The Neumann boundary value prob-lem is firstly reduced into the equivalent natural boundary integral equation withthe kernel possessing 2nd-order singularity,and then the corresponding variationalproblem on the boundary is obtained.By applying Quak trigonometric wavelet basisBjsee(1.2.3as boundary elements and the method of expanding kernel functionto its Galerkin discretization,we obtain simple computational formulae of the en-tries in the stiffness matrix.

首先，我们将Neumann边值问题归化为等价的带有2阶强奇性核的自然边界积分方程，然后化为边界上相应的变分形式，以Hermite插值Quak三角小波基Bj见(1.2.3作为边界元并利用积分核函数展开法将其离散，得到了十分简单的刚度矩阵系数的计算公式，而且刚度矩阵具有十分简单的形式，它是分块循环对角阵。

There are great difference in physics quality between the inner and the outer of boundary and the local of grid in boundary, so the boundary and artificial boundary became a very strong interface to reflection wave.

由于边界内外的物性差异及边界点网格的局部性，使边界成为一个很强的反射界面——人工边界。

The essence of retreat is setting up a boundary - and we are not actually talking about a physical boundary, but we are talking about a boundary of time, setting up a boundary between past and future, which ideally means we remain in presentness.

闭关的精髓在於设定界限—我们所说的事实上并非是身体的界限，而是一种时间的界限，在过去和未来之间设定界限，理想上表示我们是住於当下。

The saltation boundary layer is divided into an inner boundary layer in which the saltating particles exert significant force on the airflow, and an outer boundary layer in which saltating particles exert insignificant force on the airflow, but the out layer is affected by the inner boundary layer.

将风沙边界层划分为跃移颗粒所产生的阻力不可忽略的内边界层和跃移颗粒阻力可以忽略但受内边界层影响的外边界层，分别建立了内边界层和外边界层的风速廓线表达式。

Through discussing further the reflective and refractive coefficients of line boundary, the features of line boundary are as follows: the attenuation of high frequency band (especially in band of line trap) of transient components generated by fault through line boundary is obvious, whereas the low frequency band (1~10kHz) components are hardly influenced. Moreover, the transient components below 100kHz should be adopted in purpose of outstanding the line boundary and weakening the transmission influence of transmission line.

通过对线路边界的透、反射系数的进一步分析发现：暂态信号的高频段穿越线路边界时将大为衰减，而低频段(1~10kHz)几乎不衰减；为弱化线路的传输影响而突出线路边界的作用，宜选用100kHz以下的信号分量。

Objective:To explore the feasibility of laparoscopy in diagnosing and treating of abdominal diseases.

目的：探讨腹腔镜用以诊断腹部外科疾病及选择治疗方案的可行性。

The lifetime of nylon 1010 and nylon 1010/POSS composites decreased with increasing temperature.

热重-红外联用分析表明尼龙1010在氮气气氛下的降解产物主要为小分子的低聚物，POSS并不改变尼龙1010降解产物的组成。