导出代数

We also discuss a natural involution of necklace Lie algebra .

我们还讨论了由重箭图自然自同构导出的李代数的一个自然的对合。

In this paper,a rational approximation method of the norm of parametric speed is given,which is more effective than the polynomial approximation.

文章根据等距曲线逼近的关键在于对其参数速度模的逼近，提出了对参数速度模有理逼近的2种形式，在此基础上给出了平面Bézier曲线等距曲线的逼近函数和误差估计函数，并导出了保持法矢平移方向的代数方式的等距有理逼近算法。

Using the recursive formula and computer algebra system-Mathematica, the first six singular point values at infinity of the system are given.

对一类三次系统给出了计算无穷远点奇点量的递推公式，并在计算机上用计算机代数系统Mathematica推导出该系统无穷远点的前6个奇点量，进而导出了无穷远点成为中心和最高阶细焦点的条件，在此基础上得到了一个三次系统在无穷远点分支出6个极限环的实例，指出了极限环的精确位置。

The one is the to poiein, or the principle of synthesis and has for its objects those forms which are common to universal nature and existence itself; the other is the to logizein or principle of analysis and its action regards the relations of things, simply as relations; considering thoughts, not in their integral unity but as the algebraical representations which conduct to certain general results.

一曰创造或综合法则，而尊此法则所归纳的对象被赋之以普遍存在和其自身拥有的共性形式。二曰逻辑或分析法则，它的作用关乎事物间的联系，仅仅是联系。它并非从整体上看待思想，而是将其视为多个代数上的呈示，这些呈示最终将导出某个必然的结果。

The derived equivalences of extension algebras are studied in the second chapter.

第二章我们讨论扩张代数的导出等价。

Finally,through some ideas from Algebraic Geometry,we constructed strongly exceptional collections of derived sheaf categories,and solved the problem that equivalences between some posets.

最后，通过代数几何里的一些思想，我们构造了导出层范畴的强例外集合，解决了一类偏序集的等价问题。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。