查询词典 null character

Then,the system is linearized by variational approach,the local null controllability is proved by applying a generalized implicit function theorem and combining the property of the solution mapping.

首先得到了系统的逼近能控性；然后采用变分方法对系统线性化，再结合解映射的性质，应用推广的隐函数定理，证明系统的局部零能控性；最后给出系统零能控的结论。

Then, the system is linearized by variational approach, the local null controllability is proved by applying a generalized implicit function theorem and combining the good property of the solution mapping.

首先通过对系统线性化，构造泛函，利用对偶方程，给出控制函数具体形式的办法得到系统的逼近能控性；然后采用变分方法对系统线性化，再结合解映射好的性质，应用推广的隐函数定理，证明系统的局部零能控性；最后利用局部零能控性和逼近能控性结合给出系统零能控的结论。

Anything we said 6 months ago is inadmissible in an argument. In fact, all comments become null and void after 7 Days.

任何一件我们争论了6个月的事，实际上，在开始7天之后，任何解释都变成无效的和没意义的。

In fact, any number of rows can include nulls for columns without NOT NULL constraints because nulls are not considered equal to anything.

由于空值与任何值比较都无意义，因此定义了 UNIQUE 键约束而没有定义 NOT NULL 约束的列上可以包含多行值为空的记录。

Bitmap indexes can include rows that have NULL values, unlike most other types of indexes.

与其他大多数索引不同，位图索引可以包含键值为 NULL 的行。

Bitmap indexes can include rows that have NULL values, unlike most other types of

与其他大多数索引不同，位图索引、可以包含键值为NULL的行。

Bitmap indexes include rows that have NULL values, unlike most other types of indexes. Indexing of nulls can be useful for some types of SQL statements, such as queries with the aggregate function COUNT.SELECT COUNT FROM employees

对于select count from tab，全表扫描比使用索引效率要高，经过分析的表cbo会倾向于使用索引，这是oracle软件的判断问题，最好还是不要收集统计信息，让oracle执行全表扫描。

It is shown that the insensitivity conditions are equivalent to the null controllability problem of a cascade system.

不灵敏控制问题是能控性的一个分支，半线性热方程的不灵敏控制问题即可转化为一个串联系统的能控性问题。

That's because int are value types and can never be null.

这是因为int是值类型而且永远也不能为null。

VWMO Intercomparison of models for snowmelt runoff Operational Hydrology Report 23(WMO No.646), 1986,null

张勇%刘时银%丁永建中国西部冰川度日因子的空间变化特征地理学报， 2006，1

Must have Coordination and negotiation skill, flexible ideas, and be punctilious person.

必须具备较好的协调与谈判能力，头脑灵活，工作认真仔细

Result: 18 patients are all with simple eye.The pigment mole lies in nasal and temple sides of the ball conjunctiva,in which 2 lie in lacrimal caruncle and semilunar plica.

结果：18例患者均为单眼，色素痣大多数位于内外侧睑裂部球结膜面，2例位于泪阜及半月皱襞，经激光治疗后，10例色素痣消失，有5例行再次激光后消失，2例行第三次激光后消失，1例第四次激光后消失。