vector n. 1.【数学】向量,矢量,动径。 2.【航空】飞机航线;航向指示。 3.【天文学】幅,矢径。 4.【生物学】带菌者[体],传病媒介。 vt. 【航空】(对飞行中的飞机)指示航向。 vi. 【航空】电(磁)波导航。
current adj. 1.通用的,流行的。 2.现在的,现时的,当时的。 3.流畅的;草写的。 the current price 市价。 current news 时事。 current expenditure 经常费。 current expenses 日常费用。 the current issue [number] (杂志的)本期。 the current week 本星期。 the current year 今年。 the 10th current [curt.] 本月十日。 current account 往来存款账;【法律】交互计算。 current English 现代通行英语,日常英语。 current handwriting 草书。 current money 通行货币。 current rate 现价,成交价。 current thoughts 现时代思潮。 pass [run, go]current 通用,流行。 n. 1.水流;气流;电流。 2.思潮,潮流;趋势,倾向。 3.进行,过程。 a cold current 寒流。 the Japan current 日本海流,黑潮。 the great current of events 天下大势。 a density 密着(海)流。 an alternating [a direct] current 【电学】交[直]流电。 current of air 气流。 current of time [the times] 时势,时代潮流 (go [swim] with [against] the current of the times 顺应[违反]时势)。
According to different assessment aim , there were many different index - systems and assessment styles . depending on current newness rate analysis a new idea - general newness rate was set forward . it changed single vector current of newness rate to multi vectors and large its extent of feasibility 最后,依照多指标综合评价思想,在现有成新率分析基础上,提出广义成新率概念,将原有的成新率评价的一维空间拓展到多维空间,丰富了评价内容,拓宽了适用范围,不仅可以用在设备系统估价,同时也可以用在设备系统决策的很多领域。
The safety of transmission line plays a important role in power system safety it is not only the requirement of ensure supply power reliability , but also the necessary precondition of enhance power system stabilization , to remove faulty line quickly and accurately , also keep non - faulty line continuous work when some transmission line faults current differential protection is a kind of simple , reliable and good - selective protection manner to any variety of transmission lines , power system development needs current differential protection apply to transmission lines , moreover the advancement of electric and communication technology enable current differential protection apply to transmission lines firstly , the paper discusses , analyses the research and application transmission line protection in detail , compare the principle and realistic presupposition of general line pilot protections secondly , because conventional current vector differential protection are influenced easily by load current and transitional resistance , in order to at the same time quicken protection act , the principle and criterion include work characteristic of differential protect based on fault component sampled values are studied , results shows that differential protect based on fault component sampled values excels general vector current differential protection in reliability , sensitivity and anti - saturation of current transformer in addition , synchronous current sampling methods at all terminals of line is analyzed and estimated lastly , the principle and criterion . also device design about current sampling values differential protection based on optical fiber communication , which apply to short transmission lines are concretely investigated , 基于基尔霍夫定律的电流差动保护无论对于何种形式的输电线路都是一种简单、可靠、选择性强的保护形式,电力系统的发展使得电流差动保护应用于线路保护成为需要,而电子、通信技术的发展使得电流差动保护应用于输电线路成为可能。首先,本文对目前线路保护的研究和实际应用情况进行了讨论和分析,比较了常用线路纵联保护的实现原理和实现条件及优缺点。其次,针对常规相量电流差动保护易受正常负荷电流和故障过渡电阻影响的缺点,同时为加快差动保护的动作速度,对基于故障分量瞬时采样值电流差动保护的原理、判据、动作特性等作了讨论和分析,结果表明基于故障分量瞬时采样值电流差动保护在可靠性、灵敏度、抗电流互感器饱和方面明显优于常规相量电流差动保护,对电流差动保护各端的同步采样方法和数据通信也进行了分析和评价。