查询词典 initial approximation

The basic relationship between the the first half-wave peak value of transient current and the initial firing angles is found by means of analytical method.The practical method is put forward to determine the initial two-phase and the third phase firing angles with the limiting value and the space vector varying track of transient current.And then the subsequent series of firing angles with the even step are calculated by using the speed at the time of re-switching.The suppressive effect to the inrush current is verified with simulation and experiment of rapid soft re-switching control,by which the influence of different speed to rapid soft re-switching course is analyzed besides.3 To analyze the power loss for typical periodically variable running load and deeply study the energy-saving principle and control mode of the intermittent power supply approach. Futhermore,the novel integrated energy-saving control technique is developed on base of the intermittent power supply approach.

通过解析方法找到快速软投入初始触发角与瞬态电流首半波峰值之间的基本关系，进而提出了由限流值和空间向量轨迹确定初始两相和第三相触发角的方法，并以固定步长均匀递减的方式由投入时转速计算出其它后续触发角；结合仿真和实验验证了快速软投入对冲击电流的抑制作用，并分析了不同转速下投入时对电源快速软投入过程的影响。3对典型周期性变工况负载特性进行能耗分析，深入研究断续供电节能机理和控制模式，并进一步发展了以断续供电为主的综合节能控制新技术。

Under the condition that the flux function has one inflection point, by the structure of weak entropy solution of the corresponding initial value problem and the boundary entropy condition developed by Bardos-Leroux-Nedelec, we give a construction method for the global weak entropy solution of the initial-boundary value problem arid clarify the solution structure nearby the boundary.

在流函数具有一个拐点的条件下，由相应的初始值问题弱熵解的结构和Bardos-Leroux-Nedelec提出的边界熵条件，给出初边值问题整体弱熵解的一个构造方法，澄清弱熵解在边界附近的结构。

Since the initial start of buried pipelines results in three-dimen-sional unstable heat transmission , and at initial start the temperature change of the soil around a pipeline is affected by the temperature inside the pipeline and the ground surface temperature annual fluctuation, the differential equation for heat transmission and the boundary value may be line...

埋地输油管道启输过程是三维非稳定传热问题，启输过程中管周土壤温度场的变化受管内热水温度和启输前地表面温度年波幅的影响，可将传热微分方程和边值条件线性组合成两个定解问题，用电子计算机进行数值求解，得出计算公式，以确定预热阶段管路任一点任一时刻的热水介质温度。

Several nitramine propellants are quenched at different initial pressure(up to 300 MPa)by rapid pressure decay in a small-sized ballistic simulator, which is different from the ordinary vented chamber in that it creats the burning environment of the propellant similar to that gun bore,and that the initial pressure before the extinction are relatively high.

用改进的小型弹道模拟装置，对几种硝胺发射药做了中止燃烧实验，中止压力达300MPa，并对中止燃烧样品做了SEM电镜观察。

Applied with test of potted plant and measurement absorbency for study response of the contents of photosynthetic pigments of slash pine's half-sib under water stress. There are 7 families comparison with general slash pine. The contents of photosynthetic pigments are mensurated under feebleness water stress while soil water content is 55% to 60% and moderate water stress while soil water content is 35% to 40% and heavy water stress while soil water content is 20% to 25%. The test result indicate that either water grads or families of chlorophyll and chlorophyll a and chlorophyll b and Chla/Chlb and carotenoid and Caro/Chl are mighty notable difference. The Chl and Chla and Chlb and Chla/Chlb little drop from normal soil water to initial water stress. Then drop obvious with increased water stress. The Caro and Caro/Chl little drop firstly from normal soil water to initial water stress,then up in metaphase water stress,after drop in evening water stress. The Chl and Chla and Chlb and Chla/Chlb and Caro of slash pine'half-sib are over general slash pine. The Chl and Chla and Chlb and Chla/Chlb and Caro of 464 and 1027 are over average value of slash pine's half-sib under water stress. The Caro/Chl of 609 and 46 are over average value of slash pine's half-sib under water stress.

为研究湿地松半同胞家系光合色素对水分逆境的响应，采用盆栽试验和吸光度测定方法，以湿地松普通种子为对照，测定了七个湿地松优良半同胞家系在弱度水分胁迫（土壤相对含水量为55%~60%）、中度水分胁迫（土壤相对含水量为35%~40%）和强度水分胁迫（土壤相对含水量为20%~25%）条件下的光合色素，对湿地松优良半同胞家系在不同水分胁迫条件下的光合色素进行了研究，结果表明：无论是不同水分梯度还是不同家系水平，Chl、Chla、Chlb、Chla/Chlb、Caro、Caro/Chl均有极显著差异；从正常水分至水分胁迫初期Chl、Chla、Chlb、Chla/Chlb稍微下降，后随着水分胁迫程度的加深下降较快，从正常水分至水分胁迫初期Caro、Caro/Chl先稍微下降，胁迫中期上升，胁迫后期下降；所有半同胞家系的Chl、Chla、Chlb、Chla/Chlb、Caro高于普通种，在水分胁迫条件下家系464、1027的Chl、Chla、Chlb、Chla/Chlb、Caro高于家系的平均水平，家系609、46的Caro/Chl值高于家系的平均水平。

At first, the initial values of motion vectors of blocks in the face area can be found by calculating the 2D parameters of general head motion. With the initial values, the range of further search in motion estimation can be reduced, and the results are consistent with the actual motion.

首先提出一种通过求出脸部区的二维全局运动参数来求各像块的运动矢量初值的方法，在得到各像块的运动矢量初值后，搜索范围可以很小，搜索到的精确的运动矢量更符合真实运动。

Meanwhile,The impact of alcohol concentration,fermentation temperature,inoculums dose,initial sugar concentration,rotation speed,initial pH value to acid yield and ester yield in the process of solid-state fermenting craft was studied.

同时研究了酒精度、发酵温度、接种量、起始糖度、摇床转速、初始pH值等因素在固态发酵过程中对产醋酸和产酯量的影响。

Immobilized within loofa sponge were explored as a function of initial solution pH, temperature, contact time and initial metal concentration.

研究其在溶液中对金属离子Pb^2＋和Cu^2＋的吸附效果，并探讨其生物吸附机理，分析其动力学特性。

The results showed that in typical sunny day,when solar irradiation average intensity was 91600lx,initial concentration of methyl orange was 20 mg/L,initial pH was 3.88,A/V is 36 m-1,after 2 h irradiation the decolorization ration was 90%and after 4 h TOC removal achieved 70%.

实验结果证明了非聚焦开放式反应器构型和二氧化钛悬浆体系能很好地利用太阳能、有效地完成对甲基橙的脱色和有机碳的去除。各因素与甲基橙脱色速率的关系将作为进一步设计反应器的重要参数

By means of the fourstage theory, the Chinese urbanization course is divided into two stages: initial stage and growing stage. Then according to the particularity of Chinese urbanization course, the initial stage is also compartmentalized into six substages: successfully underway stage, acceleration stage, retrogressive stage, stagnant stage, fast growing stage and slow-footed developing stage.

根据四阶段论，将我国城市化发展阶段划分为起步阶段和成长阶段共两大阶段，其中起步阶段又可根据我国城市化进程的特殊性划分为顺利起步、超速发展、倒退发展、停滞发展、迅速发展和低速发展共6个亚阶段。

Don not attempt to do something which you can not to do.

不要企图做那些办不到的事情。

The expression of CTGF and TNF-αweredetected by immunochemistry and the number of Clara Cells was calculated.

光镜下观察肺组织的病理变化，采用免疫组化染色观察肺组织中结缔组织生长因子和肿瘤坏死因子-α的表达和Clara细胞的数量。