查询词典 variable

How to set up a command prompt window environment variable?

如何在命令提示符窗口中设置环境变量？

Variable magnetic pole DC motor can resolve the problem of commutator existing in the traditional DC motor.

变磁极性直流电机解决了传统直流电机的换向器问题。

The optimum design of variable distance mechanism of side slope compactor was performed by means of mathematical programming method and optimum design principle.

用数学规划法和"最优设计"原理对边坡压实机工作装置的变距机构进行了优化设计。

A comparable function can be defined in terms of the digital transfer function using the polar variable z by defining HH = HH (1/z) which gives the magnitude-squared frequency response when evaluated around the unit circle, i.e., z = ejw.

解析复杂值函数的复变S是定义在此背景下，逼近抵达中的F ，结果是一个解析函数法郎的因子F款，这是理想的过滤器传递函数在矩形的变数。

However, when we want to evaluate a variable to a value, we must use a comparison operator.

然而，当我们要运算一个变量的值，就必须使用比较运算符。

The high-voltage high-power multilevel converter and AC motors drive techniques are summarized compendiously for domestic and overseas studies in the prolegomenon of this dissertation. The evolution and research status of multilevel converter topologies are analyzed, the development of AC variable speed techniques and the characteristic of DTC are discussed, also, the aim and significance for the research are demonstrated. In this dissertation, SVPWM pattern and implement method have been addressed comprehensively for three-level NPC inverter.

本文绪论部分针对国内外高压大容量多电平变换技术和交流传动控制技术作了简要综述，着重分析了多电平拓扑结构的发展和研究现状，讨论了交流调速的发展和直接转矩控制技术的特点，指出本文选题的目的和意义。

The method synthesizes variable structure control laws and repetitive control laws in a complementary manner.

该方法以互补的方式综合了变结构控制律和重复控制律。

A fuzzy conditional expectation with respect to sub σ-algebra of for a fuzzy random variable is introduced in the complete probability space, and the fact that such a fuzzy conditional expectation exists uniquely is proved and its some properities are discussed.

在完备的概率空间中引进一个模糊随机变量关于■的一个子σ代数■的模糊条件期望，并证明这样定义的模糊条件期望存在且唯一，还就其某些性质作了讨论。

In this paper we acquaint the reader first with the algebraic semantics which is corre-sponding to the Kripke's semantic having nested domaius. By an application of the completenesstheorem on relational semantics of the quantified normal modal systems with nested domains proved in Hughes and Cresswell's method to prove a completeness theorem on relational algebraic semantics of those system. Next for normal systems with semantics which admits arbi-trarily variable domains we use Henkin's method to prove a c...

本文首先讨论嵌套论域语义的相应代数语义并由Hughes和Cresswell在［5］中建立的关于具有嵌套论域的正规量词模态系统的关系语义完全性定理推出其相应的代数语义完全性定理：然后对于具有任意可变论域语义的正规系统，我们用Henkin方法给出其关于狭义Kripke语义的关系语义完全性定理，由此通过将关系语义转化为代数语义从而亦推得其代数语义完全性定理。

to reduce the impact of carrier frequency offset in ofdm system,this thesis designs a new carrier frequency offset estimation scheme for ofdm system.the carrier frequency offset estimation includes acquisition and tracking.we adopt variable step size adaptive algorithm.the acquisition range of the proposed algorithm is as large as one half of the overall signal bandwidth.through this method we can not only avoid the feedback by using forward error correction,but also reduce the times of complex multiplication in order to reduce the power consumption of the system.this algorithm not only has low complexity and fast convergence nut also can improve the demodulation performance of ofdm system.computer simulation illustrates the superior performance of the proposed algorithm with regard to estimation accuracy in both awgn channel and multi—path channel.

摘 要：为了减小正交频分复用系统受频率偏差的影响，在ofdm系统中设计了一种新的载波频偏估计算法。频偏估计包括跟踪和捕获两个阶段，文中采用变步长自适应算法来进行跟踪，这个跟踪算法的捕捉范围是整个信号带宽的一半。通过此方法，不但可以利用前向纠错的方式来避免反馈，而且可以缩减复数乘法的次数以降低计算复杂度和系统功耗。该方法运算复杂度低，并具有较好的收敛性，能改善odfm的解调性能。从计算机的仿真效果可以看出无论是在awgn信道上还是在多径信道上都表现出了卓越的性能。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。