查询词典 a set

To take just one example, consider the set theorist's axiom of extensionality : For any sets A and B , if A and B have the same members, then A is the same set as B .

举例说，考虑集合论的外延公理：对任何集合A和B，如果A和B有相同的成员，那么A作为集合和B同一。

Let F be a bijection from set A to set B. Denote M={a Aa F}. If in a theory that ME B is legitimate, then the question m E M?

令F是从集合A到集合B的双射，记M＝aAaF，如果在某个理论中M B是合法的则问题m M？

According to the demand of high magnetic field power supply, reference is increased with a set ramp rate and stops at a set stable value, so reference system is composed of digital setting and digit to analog converting circuit. But the stability of reference is mostly guaranteed by the performance of D/A circuit, so D/A circuit is particularly studied in reference system. The scheme of D/A circuit, the selection of DAC and its voltage reference, hardware anti-jamming design and PCB design are discussed in detail, and software of remote control and PLC are discussed in brief. Zero-flux DC current transformer well satisfies the demands of the high stability of Load current detection unit, so the principle of zero-flux DC current transformer is analyzed; in the mean time a project which detects the long term stability is designed. During 8 hours, analog signal which is detected with high precision digit multimeter is recorded in computer at 1HZ frequency by GPIB communication. The drift error source and related parameters are explained in the compare-amplify part. Detailed subtraction circuit is designed; also amplifier chip and periphery components are selected and verified according to the theory of error analysis.

根据强磁场电源的需求，参考源应按照软件设定的斜率逐渐上升到设定稳态值，则参考源系统应由数字给定和数模转换电路两大部分组成，而参考源的稳定度主要依靠完成数模转换功能的模拟电路的性能来保证，因此本文对参考源系统的研究以数模转换电路为重点，分别从电路方案的确定、数模转换芯片及其基准电压源的选取和验证、电路板硬件抗干扰和PCB设计几方面进行了论述，然后对数字给定部分的远控组态和PLC程序设计作了简要介绍；采用零磁通原理的直流电流转换器很好地满足了对负载电流检测单元高稳定度的需求，本文详细分析了零磁通检测的原理，并在选定此种类型电流转换器的基础上设计了一套检测长期稳定度的方案，8小时内以1秒为采样周期，通过计算机Labview程序和高精度数字电压表的GPIB通讯，将被高精度数字电压表数字化后的模拟信号采样值连续记录至计算机中；比较放大环节简要阐述了漂移产生的原因和相关参数指标，确定了具体的减法电路形式，并根据误差分析理论对运算放大器和外围元器件进行了选取和验证。

In particular, the system generates bifurcation when 2c-a=0, and then the stable knot bifurcates a hyperbolic saddle point and stable convergence, which is so-called Pitchfork bifurcation. From 2c-a≤0 to 2c-a≥0, the attracting set A of the system is changed from single point to the union set of two different old orbits.

系统在2c-a=0时产生分岔，其稳定的结点分岔出一双曲鞍点和两个稳定的汇，这就是Pitchfork分岔，可见在2c-a≤0变化到2c-a≥0时，吸引集A从单点集变成为连接P和P的两异宿轨道的并。

A set with an associative binary operation under which the set is closed, which contains an identity element and an inverse for every element in the set.

群二元结合运算为闭合的数学集合，具有单位元素。集合中每一元素都有逆元素

Mathematics A set with an associative binary operation under which the set is closed, which contains an identity element and an inverse for every element in the set.

群：二元结合运算为闭合的数学集合，具有单位元素。集合中每一元素都有逆元素 adj。

The invariant set of descending flow is a set that if the initial point in it, then all the flow in the set.

而下降流不变集就是那些如果初始点在其中，整个流线也在其中的集合。

The set of representable values of type T , or numeric set of T , is a set of numeric values whose elements are the representation of some subset of N .

类型 T 可表示的值的集合，或者说 T 的数字集合，是指一个数字值的集合，其中的元素是 N 的某个子集的表示法。

The PID parameter tuning of non-linear control system is set as the engineering background. The aim is the optimal design of PID parameter. On the basis of the design and research of the advanced PID parameter tuning, the mathematical model-transfer functionis developed through correlation analysis on statistical method.And with the optimization algorithm under constraint condition, the non-linear, Isqnonlin is set as object function. Then with connection of the non-linear constrain optimization algorithm and simulink technique, a set of adjust parameters which fit the performance index of the control system are found. And optimization design process and steps are provided.

本文以非线性控制系统PID参数整定为工程背景，以PID参数的优化设计为目标，在分析和研究国内外PID参数先进整定方法的基础上，运用相关分析实验统计方法建立对象的数学模型——传递函数，把PID参数设计问题转化为一种非线性优化设计问题，借助于约束条件下的优化算法，以非线性最小平方指标为目标函数，将非线性约束优化算法同Simulink仿真技术相结合，找出符合控制系统品质指标的一组调节参数。

In this set system, the set element named quorum is a set of points, and every two quorums intersect.

在这种集合系统中；所有集合元素都是节点的集合，任何两个quorum都有交集。

By the time of its fall, most of the prisoners were writers who had written against the corruptions of the government.

到它被攻陷的时候，里面多数的犯人是写了反对政府贪污文章的作家。

The most obvious variation to ovum morphological character was that the color was changed from light green to sepiaceous in embryonic development, and all the ovums were almost hatched after 96h.

在胚胎发育过程中卵的形态特征最明显的变化是颜色从淡绿到深褐色，卵在发育96h后卵基本全部孵化。