有变化的
- 与 有变化的 相关的网络例句 [注:此内容来源于网络,仅供参考]
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These regulations are valuable to foretelling the future global change of climate.
用已经了解的这种变化规律来予测未来气候变化是有价值的。
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The study has shown:(1) With increasing sediment depth and the woody giblets, the total organic carbon, the extraction of benzene , the total humic acids and the unhydrolyte are enhanced, while the hydrolyte is decreasing.(2) According to the GC-MS analysis, n-alkane,n-alkan-2-ones and n-alkanones are composed mainly of long-chains,such a result is thought to be characteristic of a herbaceous input from 2300a.B.P. n-alkanones exist in the samples may be considered as the evidence of microorganisms activity.(3) It is showed that the lipids is more sensitive to the climate change than the floristic. The proxy of the pollen spore of the peat stratum is different from the normal environment proxy. It is one of the main reasons that the sensitivity difference of the bog vegetation reacting to the climate isn't accordant with the log of the fat molecule fossil and biology fossil.(4) The transformation of the peat organic carbon is under the influence of temperature,acidity,organic material constituting, etc, and it showed the up-trend with the depth. In the short-term scale, the conversion of the peat organic carbon is effected by seasonal water,regional climate and vegetations; while in the long-term scale, it is controlled mainly by the climate.(5) According to the comparing the orderliness of organic compound,vegetation giblets with the depth to the characteristics of the peat molecule fossil with the section, in the development of this peatmire, 1500a B.P(210cm)is regard as the borderline of the late Holocene, the keynote of the front period is warm with several cold fluctuations, and the trend of the back period is dry and cold although there were several fluctuations.
研究表明:(1)随深度的增高及植物残体中木本残体的增多,总有机碳、苯萃取物、总腐植酸、不被水解物含量逐渐增高,而易水解物含量减少;(2)GC- MS分析显示,正构烷烃,直链烷基2-酮和正烷醇均以长链组分为主,揭示了该泥炭柱剖面2347a.B.P的母源输入以草本植物为主;甲基酮类和短链正烷醇的存在是微生物活性很大的生物证据;(3)通过有机分子标志物与孢粉、植物残体等指标的对比研究表明:脂类化合物对气候变化的反映要比植物种灵敏得多,不同沼泽植物对气候变化的敏感性的差异是脂类分子化石记录与生物大化石结果很难一致的主要原因之一;(4)泥炭有机碳的转化受到温度、酸度、有机物质组成等很多因素的影响,短时间尺度,泥炭有机碳的转化受季节性降水、地方气候和植被等因素的影响;长时间尺度,泥炭地有机碳的转化,受气候条件控制;(5)总结泥炭分子化石特征、泥炭有机质各组分含量及植物残体组成随深度的变异规律,分析结果显示该泥炭地层形成过程中,1500a B.P(210cm)可作为划分前后晚全新世的界线,前期的基调是气候偏暖,但又有几次偏干冷气候的反复,后期气候以干冷为主,其间虽有几次上升波动,但整体趋势不变。
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The results indicate that its dynamic stress-strain curve is hyperbolic type. The dynamic strain of LCES decreases with increasing confining pressure, cement content, curing ages and cyclic loading frequency when it is subjected to the same dynamic stress. At the same dynamic strain, the dynamic secant elastic modulus E_(sec of LCES increases and the damping ratio decreases with increasing confining pressure, cement content, curing ages and cyclic loading frequency. The curves ofσ_d~ε_d,E_~ε_d and D~ε_d with different EPS content intersect respectively, the trend of LCES deformation characteristic is inversely proportional to EPS content near the intersection. The value of dynamic strain at the intersection is about 0.5%~3.0%, the magnitude of which is related to the mixing proportions and confining pressure.
试验结果表明,LCES的动应力应变骨干曲线形态符合双曲线;在相同的动应力作用下,LCES产生的动应变随着固结压力、水泥掺量、试样养护龄期和振动频率的增大而减小;在动应变相同的情况下,随着固结压力、水泥掺量、试样养护龄期和振动频率的增大,LCES的动模量增大而阻尼比减小;随着加载次数的增大,LCES的动模量在开始阶段显著降低,然后趋于稳定,但当加载次数达到几百次时,动模量又有增大的趋势;不同EPS掺入比的LCES的动应力应变骨干曲线、动模量随应变变化曲线和阻尼比随应变变化曲线都发生了相交,交点前后EPS掺入比的大小对LCES动力变形特性的影响趋势是截然相反的,交点处的动应变值一般在0.5%~3.0%范围内变化,其大小与LCES的配比以及固结压力有关。
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ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.
本论文针对车载异步电机在矢量控制器所遇到的问题:定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案:分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算,分析出对于电流型逆变器在采用定子磁场定向时,其性能同时具有矢量控制和直接转矩控制两者的优势,并对电压型逆变器在转子磁场定向下的模型进行了仿真研究;建立异步电机非线性模型,推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程,并做出了仿真结果,建立异步电机在非线性模型下的矢量控制调节器的PI参数设计,在实际应用中,若忽略电机电感的动态变化,可以根据当前的磁路饱和状态而在线修正电感参数,从而将非线性方程线性化,降低控制器的复杂度;考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出,本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题;推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通,用于实现高性能的矢量控制算法,并给出了仿真结果;推导出了电动汽车恒转矩给定的闭环回馈制动系统,实现了电动控制模型和制动模型的统一,而且结合铅酸电池最大充电电流的要求,为制动转矩在线给定建立了数学模型;设计了基于双DSP系统的高性能矢量控制器软硬件框图,并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。
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The changes of the SOD and LOX activity are respective different with DL, but it is closely related to the DL.
虽然SOD活性和LOX活性有不同的变化趋势,但都与延迟发光的变化存在密切关系。
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As a matter of fact, Chinese also uses morphological processes, such as suffixation of the argument names, and English also zero-marks its nominalization, such as conversion by zero affix.
汉语名词化也有形态特征,如各种有标记的论元名称;英语名词化也有无标记变化,如零缀派生名词。
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The climate had a tendance of becoming cold and dry and then turns to warm and moist.
气候变化的幅度愈来愈大,而其频率却逐渐降低,气候变化有一个趋于变冷干再变暖湿的趋势。
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Each device has its own parameters, along with the time and temperature changes.
每台设备都有自身的参数,随着时间和温度的变化而变化。
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And so tree peony is the main economic support of the product area of tree peony .All of this need a systemic and scientific cognition of the rules of grow and development of tree peony. But as the study on the physiological and biochemical changes during the period of forming strong buds of tree peony is concerned, the level is very low and still use the traditional methods of cultivation and management . So if we want to get the quality flowers ,we should have quality buds and we should use all methods ,if we can , to meet the conditions that tree peony needs. And so it is very important for theory and practice to study the physiological and biochemical changes during the period of forming strong buds of tree peony.
但是,不论是生产商品苗木还是用于反季节催花,都需要对牡丹的生长发育规律有一个系统和科学的认识,然而,目前的牡丹栽培仍然衍用传统的栽培技术,对牡丹生长发育过程中的生理生化变化规律的认识,却还停留在比较肤浅的水平和层次上,因此要得到高质量的牡丹花,就要有高质量的牡丹芽,就必须按照牡丹的生长发育规律,建立科学的栽培技术体系,在牡丹壮芽形成过程中运用一切可以运用的栽培措施、管理技术来满足条件,因此,对牡丹壮芽形成过程中的生理生化变化的研究就具有十分重要的理论和实践意义。
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And p 1 in sample LM 4640, in the SdH regime, implies that the unscreened piezoelectric scattering is relatively important.
至於在样品LM 4646中,由p 2至p 1的变化在过去并没有被观察到,其变化的行为似乎也可能与绝缘态-量子霍尔相变有某些相关。
- 推荐网络例句
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Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).
呼气,收缩臀部肌肉;拱起身体,尽量抬起头来,右腿伸直朝向天花板(膝微屈,以避免肌肉紧张)。
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The cost of moving grain food products was unchanged from May, but year over year are up 8%.
粮食产品的运输费用与5月份相比没有变化,但却比去年同期高8%。
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However, to get a true quote, you will need to provide detailed personal and financial information.
然而,要让一个真正的引用,你需要提供详细的个人和财务信息。