查询词典 constant current

Therefore, if we have a way of holding emitter current constant through a transistor, the transistor will work to regulate collector current at a constant value.

于是，只要我们能让晶体管的发射极电流保持恒定，它就能保持发射极电流为恒定值。

The principle of constant power drive is: PD converts the change of output light power of laser diode into the change of diode current, and the change of current is feed back to voltage-current converser which adjusts output current of driver to compensate the laser diode.

这样，当激光器的输出光功率衰减时，驱动器相应的增大输出电流；当激光器的输出光功率增强时，驱动器就相应减小输出电流。对许多激光器应用来说，最希望脉冲输出，因为脉冲输出只有极小的结发热。

Following this rationale, if we were to hold the base-emitter voltage of a transistor constant, then its emitter current should likewise be constant, given a constant temperature

根据这个基本原理，如果我们能保持晶体管发射结电压恒定，当温度恒定时，发射极电流也将保持恒定。

The theory and application is explained in this paper. Software XMGREDIT5 matching ELCIRC is used to generate unstructured grid, and is considered fit for ocean but rivers. Tidal current is simulated and validated well, and sensitivity of current structure to bathymetry is visible. Affection of wind is qualitatively analyzed here. At the same time the model is improved on as required, like the tidal open boundary which could choose not only long period harmonic constant but also short period harmonic constant and tidal level, and multi-point results and flow field data could be exported effectively with binary results.

本文介绍了ELCIRC的理论及使用；基于其在Linux平台下的软件XMGREDIT5生成全三角形网格并评价其特性，认为XMGREDIT5较适合大范围海域而不适用于河道；应用ELCIRC模型计算了长江口的潮流场并进行验证，结果与实测资料吻合良好，且能较好地模拟出地形变化对水流结构的影响；文中对于风场的影响作了定性分析，同时根据实际需要对模型作了改进，如将仅支持长期资料调和常数的开边界条件改为可选择的短期调和常数边界和潮位边界，使二进制格式结果文件数据输出可以处理多点数据及流场等等。

A quick and correct forecast of tidal current when oil spill occurs is a key step in the forecast of oil spill. Based on the harmonic constant of tidal component of M2, S2, O1 and K1 in Lingshan Island, Laoshantou and Chaolian Island, and by using harmonic method, the thesis first conducts a current forecast in a single point, and then builds up a current field forecast in Jiaozhou Bay and its adjacent seas. The computed results match well with the actual situation. The method reduces greatly the time of real time current forecast by not using numerical stimulation, so it fit to the two requirements of quickness and correctness in oil spill forecast system.

迅速准确地预测出溢油发生时的潮流情况是溢油环境预测的根本保证，因此文中根据灵山岛、崂山头和朝连岛三处M2、S2，、O1和K1四个主要分潮的调和常数资料，采用调和的方法进行单点的潮流预报，进而建立了胶州湾及邻近海域的预报潮流场；该方法的潮流预报结果与实际情况吻合良好，且因避开了数值计算过程而大大减少了流场实时预报的机时，符合溢油应急预报系统所要求的准确与快速。

The results showed that the W content in the electrodeposits rose with the increasing of cathodic current density in the solution containing ammounium citrate as complexing agent,whereas the current efficiency remained approximately constant. When the current denisity was higher than 15 A/dm2, the W content in the alloy was not obviously changed, but the current efficiency remarkably decreased.

结果表明，在以柠檬酸铵为络合剂的镀液中，沉积层的W含量随电流密度的增大而增加但电流效率变化不大，当电流密度超过15A/dm2后，镀层的W含量不再发生明显的变化而电流效率却明显降低。

L Applied battery range is wide: charge current can be set between 10% to rating, can't be influenced by the change of input current and voltage, keep constant in the process of constant charge and no need hand adjustment.

l 适用电池范围广：充电电流可在10%-额定值内任意设定，且不受输入交流电压变化的影响，在恒流充电期间电流维持不变，无需人为再调整。

L Applied battery range is wide: charge current can be set between 10% to rating, cant be influenced by the change of input current and voltage, keep constant in the process of constant charge and no need hand adjustment.

l 适用电池范围广：充电电流可在10%-额定值内任意设定，且不受输入交流电压变化的影响，在恒流充电期间电流维持不变，无需人为再调整。

The principle and current loop dynamic response are analyzed for both constant frequency current mode control and newly presented quasi-constant frequency hysteresis PWM control, experiments have been carried out to proof the analysis.

文中对现有的固定频率电流模式控制方法和所提出的准固定频率PWM电流控制方法的原理和闭环响应进行了分析，并通过实验证实了分析的正确性。

A novel quasi-constant frequency hysteresis PWM control approach is presented in this paper. Frequency feedback is introduced in hysteresis current control to stabilize switching frequency. Comparing with the common used constant frequency current mode control, the new approach has better stability, faster transient and higher precision, as well as elimination of sub-harmonic oscillation.

摘 要：本文提出了一种新的准固定频率滞环PWM电流控制方法，该方法在滞环电流控制的基础上，引入频率反馈控制，使开关频率基本固定，解决了目前广泛使用的固定频率电流控制方法具有的次谐波振荡的问题，并且具有稳定性好、相应速度快、控制精度高的优点。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。