代数化

The sixth part: Studies on the dynamic changes of soil retention function value of ecosystem in YUYANG District. Utilized ERDAS8. 5 to interpret the remote sensing image and get LUCC data and vegetation information of YUYANG District. Utilized R2V5. 5 to digitize administrative map, topographic map, vegetation picture, soil distribution map and meteorological website map. Utilized ARCINFOR8. 3 to change every digitization layer to the same projection, to generate Tyson polygon, to structure DEM and do vector polygon overlay. Utilized ARC VIE W3. 3 to obtain the grid data topographic slope and slope length from DEM data of YUYANG District, and then, turned every coverage layer into grid layer and do grid polygon overlay to gain data about dynamic changes of value of soil retention of ecosystem in YUYANG District, at last, the author analyzed the features of the spatial-temporal changes and its reason.The seventh part: Studies on the dynamic changes of fixing drifting sand against wind function value of ecosystem in YUYANG District.

第六部分：榆阳区生态系统土壤保持功能价值动态变化研究；利用ERDAS8.5对遥感数据进行解译获得榆阳区土地利用数据和植被信息，利用R2V5.5数字化榆阳区政区图、地形图、植被图、土壤分布图及气象站点分布图，利用ARCINFOR8.3对各数字化图层进行投影转换、泰森多边形生成、DEM构建和叠加分析，利用ARCVIEW3.3从DEM数据中获取榆阳区的坡度、坡长面域数据，并将上述各图层格网化，然后通过栅格图层叠加分析和代数运算获取榆阳区生态系统土壤保持功能物质量和价值量时空动态变化数据，最后分析了其变化的时空特点及形成原因。

We prove that a diagram can be drawn with conicoid sequentially if and only if it can be described by a set of triangular equations of degree less than nine.

同时证明了一个三维几何图形可以用平面、球面和圆锥曲面构造出来的充分必要条件是这个三维几何图形可以用一个三角化的次数小于9的代数方程组来描述。

The generalized criterion for minimum zone in the determination of form error of surface is presented on the basis of linear minimax techniques, and the criteria of such surfaces as for cylindricity and straightness with arbitrary direction are derived from this generalized criterion.

本文讨论形状误差最小区城的判别准则和判别方法。根据线性极差极小化问题解的特征，给出形状误差最小条件的统一判别准则。推导出各种形状误差最小区域判别法(包括圆柱度误差和任意方向直线度误差)，并在几何判别的基础上得出代数判别的格式。

In this thesis, we mainlystudy some problems on approximate implicitization and piecewise algebraic varieties.

本文主要针对参数曲线曲面的近似隐式化和分片代数簇的某些问题展开研究。

C.R.Miers has shown that the Lie triple derivation on a vN algebra M with no central abelian summands has the form D +λ, where D is an associative derivation and A is a linear map of M into its center which annihilates brackets of operators.

Miers证明了无交换部分的vN代数M上的三元Lie导子具有D+λ形式，其中D是M上的结合导子，λ是从M到它的中心Z上的线性映射且零化M中的括积。

One studying collaborative product design system was established, including: the structure and function of framework, self-study, self-adaptive, and self-organized collaborative design unit, Assistant Design Agent , communicative agent are discussed.

3分析了协同设计中知识表示和共享的研究现状，提出了将术语分为概念的内涵与外延，建立了术语含义一致化体系，包括概念内涵树和基于布尔代数的属性空间，解决协同设计中术语含义不一致的问题。

We introduce a new and special class of quasi-hereditary algebras A_q, and prove the Hemmer-Nakano equivalences for them provided that q is sufficiently large.

此外，通过研究A_q的拟遗传子代数和拟遗传商代数的同调性(来源：2a06Aa0BC论文网www.abclunwen.com)质，我们证明了一类广义Schur代数具有双中心化性质。

Gram-Schmidt algorithm is one of the fundamental methods in linear algebra, which is mainly used to compute QR decomposition.

Gram-Schmidt正交化算法是数值线性代数中的基本算法之一，主要用于计算矩阵QR分解。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷