脉管

Later, it makes some comparison with four kinds of modulation technique, and finally, it implements the three-level PWM switching power amplifier with the PWM technique. The power of the amplifier is 2kVA, and the frequency bandwidth is 10～3kHz. In the thesis, the author designs and makes the hardwares of the switching power amplifier. The hardwares contain power inverter rank circuit, control system circuit based on DSP, drive and isolation circuit, and protective circuit. The thesis also analyses the potential safety problems and put forward some solutions for the problems. Furthermore, the thesis accomplishes the software design of the control system, and successfully debugs it. The methods of designing higher power ampilfier are also discussed in the thesis. It analyses the feasibility of the methods, outlines the way of how to design higher power switching power amplifier, and does some experiments with the method of switches-parallelling.

根据电动振动试验系统对开关功放的要求，提出了以电感电流瞬时值控制技术为基础的三电平脉宽调制开关功放的设计方案，并通过系统仿真进行了原理性论证；然后设计并制作了开关功放的硬件，包括功率转换电路，基于DSP的控制电路，驱动、隔离电路以及保护电路；针对开关功放数学模型不易得出的特点，细致分析了模糊自适应PID控制方法，在此基础上编写了控制程序；研制出一台功率为2kVA，通频带为10～3kHz的三电平脉宽调制开关功放；论文中还探讨了实现大功率开关功放的方法，分析了各种方法的可行性，给出了实现大功率开关功放的思路，并进行了并联开关管实现大功率开关功放的实验。

The sending end when the use of pulse modulation approach will be a binary digital signal into a frequency modulation of the pulse sequence, and driver fired infrared tube to the form of light pulses sent receiver will receive the pulse of light conversion to electrical signals , and then, after amplification, filtering and other treatment to the demodulation circuit after demodulation, reduced to a binary digital signal after the output.

发送端采用脉时调制方式，将二进制数字信号调制成某一频率的脉冲序列，并驱动红外发射管以光脉冲的形式发送出去；接收端将接收到的光脉转换成电信号，再经过放大、滤波等处理后送给解调电路进行解调，还原为二进制数字信号后输出。

Monitoring includes ECG; systolic, diastolic, and mean BP, preferably by intra-arterial catheter; respiratory rate and depth; pulse oximetry; urine flow by indwelling bladder catheter; body temperature; and clinical status, including sensorium (eg, Glasgow Coma Scale—see *), pulse volume, skin temperature, and color.

监测内容包括ECG；收缩、舒张和平均血压，最好用动脉内插管测得；呼吸速率和深度；脉氧测定；内置导尿管尿流测定；体温；及临床状况，包括感觉（如Glasgow昏迷等级表－）、脉量、皮肤温度和肤色等。

Monitoring includes ECG; systolic, diastolic, and mean BP, preferably by intra-arterial catheter; respiratory rate and depth; pulse oximetry; urine flow by indwelling bladder catheter; body temperature; and clinical status, including sensorium (eg, Glasgow Coma Scale—see Table 2: Stupor and Coma: Glasgow Coma Scale *), pulse volume, skin temperature, and color.

监测内容包括 ECG ；收缩、舒张和平均血压，最好用动脉内插管测得；呼吸速率和深度；脉氧测定；内置导尿管尿流测定；体温；及临床状况，包括感觉（如 Glasgow 昏迷等级表－见表2：木僵和昏迷： Glasgow 昏迷表）、脉量、皮肤温度和肤色等。

In the leaves of Liriodendroideae, some of the abaxial epidermal cells are papillose and the vascular tissue of the main vein appears to be separated. However, papillose were not found and there are uniseriate, multicellular or unicellular hairs distributed on the epidermis, and the vascular tissue of the main vein appears to be continuous in the leaves of Magnolioideae. Furthermore, in the Magnolioideae, the structure of the leaves of plants in Manglietia are different from that of Magnolia.

结果表明：鹅掌楸亚科和木兰亚科在叶的结构上的主要区别是鹅掌楸亚科两种植物叶的部分下表皮细胞呈乳突状，且整个细胞外壁只形成一个乳突，而在木兰亚科的植物中有单列多细胞或单细胞的表皮毛，未发现乳突；鹅掌楸亚科植物的叶主脉维管组织环分隔呈束状，且其外包被的纤维也排列成束状，而木兰亚科的80种1亚种植物中，叶主脉维管组织连成轮状，其外面也由一圈连续的纤维环所包围。

Leaves long petiolate, slightly pubescent along midribs and veins; panicles without floral leaves; calyx gray lanate, glabrescent and tubular in fruit

叶具长叶柄，稍具短柔毛沿中脉和脉；没有花的叶的圆锥花序；花萼灰色具绵状毛，后脱落和管状在果期 4 Isodon eriocalyx 毛萼香茶菜

Thus, a decoupling chamber pressure control system was designed and installed at the end of the tailpipe of a valveless self-excited pulse combustor. The relative pressure in the decoupling chamber was controlled from about -10 kPa to 10kPa through a blower, and the influence of pressure variation on the heat transfer in tailpipe was investigated.

在一台无阀自激脉动燃烧器尾部建立了去耦室压力控制系统，通过调节引风机前的阀门开度来改变去耦室内部压力即尾管出口压力大小（调节范围-10～10 kPa），实验研究了去耦室压力变化对脉动燃烧器尾管传热的影响。

On the foundation of the analysis,a fault diagnosis method which is an advanced pattern recognition method is proposed and a fault diagnosis system of generator excitation power unit based on virtual instrument is developed.It is proved by experiment that the fault diagnosis system can precisely judge which thirstier goes wrong and get accurate diagnosis result.

发生晶闸管直通故障时，瞬间将造成相电压短路，短路电流使保护电路动作；而发生晶闸管开路故障时(如晶闸管器件门极损坏或触发脉冲丢失等故障)，功率单元仍然工作，但输出励磁电压的脉动增大，平均值降低，这种带病工作导致励磁电压波形产生畸变，从而导致了发电机工作在不稳定状态，同时也加大了对电网的干扰[2]。

Imports of liquid from entering the rotating rotor tube cavity, the role of the centrifugal force and pressure into the receiver tube, through the receiving tube speed can be transformed into a smooth, non-pulsating pressure from the export pipe emissions.

液体从进口管进入旋转的转子腔内，在离心力和压力作用下进入接收管，通过接收管将速度能转化为平稳、无脉动的压力能从出口管排出。

Self-Exciting Mode Oscillating-Flow Heat Pipe, also called pulsating heat pipe or oscillating heat pipe, is a novel heat transfer device that has an excellent heat transport performance.

自激振荡流热管也称为脉动热管，是一种新型高效的传热元件。本文提出了采用脉冲加热代替常规连续热源加热强化自激振荡流热管传热的方法，并对其进行了实验研究。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。