查询词典 phase

Due to the fact that the intercarrier spacing in OFDM is relatively small, OFDM transceivers are somewhat more sensitive to phase noise compared to single carrier transceivers. Thus this problem must be carefully considered in designing an OFDMbased system since an accurate prediction of the tolerable phase noise can allow designer to relax system specifications. According to spectrum theorem, two components of phase noise were analyzed: common phase error and intercarrier interference. On the basis of the analysis, the performance of OFDM was given for the case where phase noise has been added to the signal, and an optimal design criterion for OFDM parameters was proposed that allows to improve the phase noise error correcting capabilities in OFDM receiver.

由于采用子载波间相互正交的结构，OFDM系统对于由本地振荡器不稳定性所导致的相位噪声影响非常敏感，针对公共相位误差CPE和载波间干扰ICI两种影响表现形式不同的干扰项，从功率谱密度函数这一独特角度分析了相位噪声对OFDM系统性能的影响，提出了旨在提高接收机抵抗相位噪声能力的OFDM系统关键参数优化与设计准则，可在对所设计OFDM系统性能加以提高的同时，有效降低对接收机前端模拟振荡器件和相位噪声抑制单元的性能指标要求，从而降低接收机硬件实现成本。

The intermetallic compounds are coarsened into nubbly Cu6 Sn5 phase by adding excessive Cu into Sn-Cu solder alloy. For Sn-9Zn-xCu solder alloys, the long needle-like Zn rich phase which is the mainly existing form of Zn in Sn-Zn solders is transformed into Cu5 Zn8 phase and fine Zn rich phase by the addition of 2% Cu, while CuZn phase and Cu6 Sn5 phase are formed in Sn-9Zn-10Cu bulk alloy. When soldering within short time under 260℃, the ripening and growth of IMC at Sn-xCu/Cu interface are accelerated with increasing Cu content in Sn-Cu solders.

结果表明，当Sn-Cu钎料中Cu的含量为2%时，基体中IMC粗化为块状的Cu6Sn8相；对于Sn-9Zn-xCu钎料合金，2%Cu元素的加入使得Sn-9Zn基体中长针状的富Zn相转化为Cu5Zn8相以及细小的富Zn相，而当Cu含量达到10％时，钎料基体中的IMC为CuZn相与Cu6Sn5相。

But in practical operating, overvoltage caused by reignition of the vacuum switching device frequently appears, and it result in damage of the capacitor bank or the switchgear itself. Ensuring the switchgear against reignition and installing a protective device are two main approaches to avoid the phenomenon. In this paper, a study on overvoltage caused by reignition due to capacitor bank switching with the vacuum switching device and its preventive measures are carried out. The main work which has been done and researches are as follows: 1. The producing mechanism of overvoltage and its influence factor are analyzed. It is pointed out that single-phase reignition is the main reason for damage of the switchgear and two-phase reignition is the main reason for damage of the capacitor bank,so overvoltage of single-phase reignition and two-phase reignition are the emphases of prevention. 2. Analysis of the special working condition of the operating switch for capacitor bank is carried out. It indicates that the vacuum switching device is difficult to realize no-reignition under this operation condition, so it is more practical to adopt protection devices. 3. Analyses of protection effect of RC and MOA and their shortages are carried out. It shows that the two methods can only restrain effectively overvoltage caused by single-phase reignition, and they cannot protect the capacitor bank when reignition of two-phase occurs. 4. The operation principle of G-R damping device is analyzed and discussed emphatically.

本文针对真空开关投切电容器组时因重燃而产生的过电压及其防治措施进行了研究，所开展的主要工作和研究结果如下： 1、对过电压的产生机理及其影响因素进行了分析，指出单相重燃是导致开关设备损坏的主要原因，而两相重燃则是导致电容器组损坏的主要原因，因此单相重燃和两相重燃过电压是防护的重点； 2、对电容器组操作开关的特殊运行条件进行了分析，指出在这种运行条件真空开关难于实现不重燃，因此采用保护装置更具有现实意义； 3、对RC与MOA的保护效果和存在的不足进行了分析，指出这两种方法均只能有效抑制单相重燃过电压，而不能在发生两相重燃时保护电容器组； 4、重点对G-R阻尼装置的工作原理进行了分析和讨论，指出该装置接入后线路中将会出现两种频率的高频振荡，而电容器组上的过电压是由这两种振荡共同决定的； 5、根据对上述两种振荡的分析指出存在一个最佳电阻值使得过电压最低，并提出了电容器组电压和最佳电阻值的近似求解方法； 6、使用电气暂态分析软件MATLAB对G-R装置的保护效果进行了仿真计算，证实该装置确实可以有效抑制重燃时的电容器组过电压； 7、根据仿真与近似计算结果的偏差提出了近似计算的修正方法，经过修正后的过电压计算结果与仿真结果吻合较好； 8、对G-R装置中放电装置G与阻尼电阻R的要求进行了分析，指出采用编织电阻和真空间隙可能是最佳选择。

The frequency value in S phase is 4. 83 times of M phase, 2. 9 times of G1 phase, and 3. 41 times of unsynchronized cells. These results suggested that gene correction events were highly related to S phase. Then we compared the targeting efficacy for two groups of cells in S phase. One group was contact with thymidine and the other one went smoothly through S phase without replication blockage.

基于这种原因，我们对基因定点修复事件做了细胞周期定位分析，发现同步于S期的细胞群发生定点修复的效率明显高于其它各期以及非同步化的细胞，流式细胞仪检测S期定点修复效率为M期细胞的4.83倍，为G1期细胞的2.9倍，是未同步化细胞的3.41倍。

--- Method and apparatus for abstracting water from air wherein in a first phase of a recurring cycle a stream of cool, moist air from the atmosphere first cools a first heat storage condenser (1) and then humidifies a hygroscopic medium (14); in a second phase a stream of warm air additionally heated by solar radiation expels moisture from the hygroscopic medium and carries the moisture into said first heat storage condenser (1) where it condenses, releasing condensation heat, and drains away; in a third phase another stream of cool, moist air from the atmosphere first cools a second heat storage condenser (2) and then rehumidifies the hygroscopic medium, and in a fourth phase another stream of warm air heated by solar energy again expels the moisture from the hygroscopic medium and carries the moisture to said second heat storage condenser where it condenses and drains away, and wherein the warm air streams of the second and fourth phases, are preheated using the heat of condensation picked up by the said second heat storage condenser (2) in the fourth phase and the heat of condensation picked up by said first heat storage condenser (1) in the second phase, respectively, before being additionally heated by solar radiation and being used to expel moisture from the hygroscopic medium.

摘要---方法和仪器取水，从空气，其中在第一阶段的周期性循环流冷静，潮湿空气从大气中的第一冷却的第一个蓄热冷凝器（ 1 ），然后humidifies一吸湿中等（ 14 ）；在第二阶段流的暖空气此外，激烈的太阳辐射驱逐水分从吸湿中等，并进行水分成表示，第一蓄热冷凝器（ 1 ）凡它凝结，释放出凝结换热，及雨水渠的距离；在第三阶段另一流的冷静，潮湿空气从大气中冷却，第一第二蓄热冷凝器（ 2 ），然后rehumidifies该吸湿中等，而在第四个阶段的另一流的暖空气加热太阳能再次驱逐水分从中期和吸湿性带有水分说，第二蓄热冷凝器而凝结及排水渠远离，和其中的暖空气流，第二和第四阶段，预热用热凝结回升，由说，第二蓄热冷凝器（ 2 ）在第四个阶段和热凝结回升，由说，第一蓄热冷凝器（ 1 ）在第二个阶段，分别之前，此外激烈的太阳辐射和被用来驱逐水分从吸湿中等。

The company main product are single phase mechanical KWH meter, three phase mechanical KWH meter, single phase electronic meter, three phase electronic meter, single phase prepaid meter, three phase prepaid meter, limit switch, micro switch, foot pedal switch, adjust switch, safety switch, cutout limiter, double-way rope pulling switch, double-way bias switch, self-lock foot pedal switch, high voltage switchboard switch, limit switch with light display, multi function limit switch, slide-stop switch, fire-control push button switch, signal light, mini circuit breaker, connector fuse cut-out, automatic photo-controls, American 6 pole computer plug.

公司主要产品：单相机械式电度表、三相机械式电度表、单相电子式电度表、三相电子式电度表、单相预付费电度表、三相预付费电度表、行程开关、微动开关、脚踏开关、限位开关、安全开关、断火限位器、拉绳开关、跑偏开关、自锁式脚踏开关、高压开关柜限位开关、带灯显示行程开关、多功能行程开关、打滑开关、消防按钮开关、信号灯、小型断路器、熔断器式保险插座、路灯控制器、美式6孔电脑插座。

This thesis deals with oil-water flow rate measurement using a venturi and develops a differential pressure-based two-phase flow rate measurement model, which does a terrific job with the use of a water fraction device. Meanwhile, Coriolis flow rate meter is also studied in the oil-water two-phase flow measurement and a SVM-based single-phase flow rate prediction method is proposed, realizing the prediction of single-phase flow rates. To overcome the disadvantages of both venturi and Coriolis flow meters, a double parameter measurement method is put forward, which combines the two meters and solves the problem of oil-water flow rate measurement. Last but not least, on the basis of the study of two-phase flow, a device for the separation of gas and liquid is designed and realizes the flow rate measurement of three-phase flow as oil, gas and water.

本文对文丘里管测量油水两相流流量进行了研究，建立了基于差压法的两相流流量测量模型，如果与含水率计相结合，可以较好的实现油水两相流的流量测量；同时研究了Coriolis流量计在油水两相流流量测量中的应用，提出了基于SVM的油水两相流分相流量预测方法，实现了油水分相质量流量的预测；针对文丘里管和Coriolis测量油水两相流存在的问题，提出了文丘里管和Coriolis流量计相结合的双参数测量方法，并实现了油水两相流的流量测量；最后，在对油水两相流研究的基础上，设计完成了一种气液分离装置，实现了油气水三相流的流量测量。

The necessity of installing phase to phase fault protection on LV side of transformer is presented in this paper by analyzing the protection capability of phase to phase impedance protection on HV and MV sides of 500kV transformer against phase to phase fault on its LV side.

通过分析 50 0kV变压器高、中压侧相间阻抗保护对其低压侧相间故障的保护能力，阐述了变压器低压侧相间故障保护配置的必要性，并对保护的配置方式提出了建议。

The concentration of D-phenylalanine in the external phase and the separation factorαcan be expressed as: The diffusion of boundary layer in outer aqueous phase is the controlled process while the concentration of D-phenylalanine in the external phase far less than the concentration of chiral carrier in the emulsion liquid membrane phase, then the diffusion coefficient k_e of boundary layer in outer aqueous phase can be achieved by data fitting.

外水相苯丙氨酸对映体的浓度以及分离因子α表示为：当外相对映体浓度远小于液膜相手性载体浓度时，该手性传质过程中外相边界层的扩散为控制步骤，利用数据拟合得到了外水相与液膜相界面边界层扩散的传质系数k_e。

Of the 60 patients, chronic nephritis 27 cases,acute serious nephritis 3 cases,essential hypertension 9 cases,diabetes 9 cases, multilocular cyst 6 cases,lupus nephritis 6 cases were enrolled. 60 CRF cases with four phase,including the phase of compensation of renal malfunction,the phase of no-compensation of renal insufficiency the phase of azotemia and the phase of renal failure,were divided into three groups.

CRF原发病为慢性肾炎27例、急进性肾炎3例、原发性高血压9例、糖尿病9例、多囊肾6例、狼疮肾6例，把这60例CRF患者根据中华内科杂志编委会肾脏病专业组于1992年6月在安徽太平举办的原发性肾小球疾病分型、治疗及疗效判定专题座谈会的标准分为四期第1期：肾功能不全代偿期、第2期：肾功能不全失代偿期、第3期：肾功能衰竭期、第4期：尿毒症期；本研究分为轻、中、重症（肾功能衰竭期及尿毒症期）3组来对照观察。

As of Tuesday, Google's results were still censored in China.

截至周二，谷歌的搜索结果仍受中国审查。

In order to make the positive action increase and negative one decrease, the sub-forces of the social factors must be adjusted to form a centripetal force.

在这一过程中，人的主体性发挥是社会有机体健康发展的灵魂。