选择交流电作为工业标准的原因很简单，在早期供电距离很短的电网里，交流电的损耗比直流电小。
The reason was that over the short distances spanned by early power grids, AC transmission suffers lower losses than DC. It thus became the industry standard.
由于在传输过程中采用高压直流电缆输送的损耗要比传统交流电的损耗小得多，因此采用交流电远距离传送电力很不划算。
Energy losses on DC lines are far lower than on the traditional AC ones, which make transmission of energy over long distances uneconomic.
现在有人开始质疑这一标准的适用性，因为在远距离输电的情况下，采用高压直流(HVDC)要比高压交流损耗小。
Some people, however, question that standard because over long distances high-voltage DC lines suffer lower losses than AC.
全内反射现象与核心玻璃的高纯度一样，使光线几乎无强度损耗传递长距离成为可能。 。
Thee total internal reflection phenomenon, as well as the high purity of the core glass, enables light to travel long distances with little loss of intensity.
众所周知，除了光纤损耗，定时抖动是限制孤子系统传输距离的关键因素。
It is well known that, apart from fiber loss, timing jitter is the key factor which limits the total transmission distance of the soliton system.
由于光放大器和各种色散补偿技术的采用，光纤损耗和色散对系统的传输距离不再起主要限制作用。
Fiber loss and dispersion have been overcome greatly because of the development of optical amplifiers and chromatic dispersion compensation technology.
由材料的失效温度及铸件的壁厚，直接找到该材料的失效距离，从而计算其损耗系数。
Based on the clay degradation temperature and casting section thickness, the degradation region can be determined directly, and the consumption coefficient can be calculated.
本文引入对数距离路径损耗模型作为LANDMARC的补充进行二次定位，通过对TOPK参考标签进行二次筛选，来实现定位精确度的提升。
We used Logarithmic Distance Path Loss Model to locate after LANDMARC and filter reference labels of TOP K second time. Finally we promoted the precision of location.
全内反射现象与核心玻璃的高纯度一样，使光线几乎无强度损耗传递长距离成为可能。
The total internal reflection phenomenon, as well as the high purity of the core glass, enables light to travel long distances with little loss of intensity.
高压直流输电系统架空线路只需正负两 极导线，可实现大功率、低损耗、长远距离电力的直接输送；
The overhead line of HVDC power transmission system needs positive and negative leads only, allowing for high power, low loss and long distance power transmission;
利用有压长距离管道运输具有输送平稳连续、安全可靠、不受污染、质量易保证、物料损耗小、占地面积少、运输费用低等特点。
Transport though long distance pressured pipeline has the characteristic of steadiness, continuity, safety, reliability, being unpolluted, little material, small needed area and low cost etc.
由于光纤的损耗大，考虑到探测器的灵敏度限制，不宜作长距离传输。
Transmission by ultraviolet fiber is not suitable for long distance considering the great losses and the sensitivity limited of detector.
HVDC技术利用地下或者海底电缆，用于远距离的电力传输，而损耗较低。
HVDC technology is used to transport electrical power over long distances with low losses using underground or submarine cables.
本发明可以不受距离的限制，避免了传统仅仅依靠电脉冲信号触发在距离远时易受干扰、信号损耗严重的缺点。
The invention has no distance limitation and solves the problems of prior art, such as interference in remote triggering with electrical pulse signals and serious signal loss.
也证明了利用超低损耗光纤远距离传感有害，有毒，易爆气体(如CH_4)的可能性。
It demonstrates that optical remote sensing of inflammable, explosive and pollution gas such as CH_4 is possible by using extremely low loss optical fiber.
半导体激光器和检测器、低损耗光纤，以及后来的光放大器的发明使得长距离传输成为现实。
The invention of semiconductor lasers and detectors, low-loss optical fiber and, later, optical amplifiers, made long-distance data transport feasible.
考虑到光纤损耗及探测器灵敏度限制，紫外光纤不宜作长距离传输。
An ultraviolet fiber is not suitable for long distance transmission considering the great loss and the limitation of the sensitivity of the detector.
讨论了光纤损耗对光孤子传输的影响，并说明当光孤子对在光纤中传播时，距离太近将会产生强烈的相互作用，导致孤子形状发生畸变。
It is pointed out that two optical solitons will strongly affect each other if they are very close, which makes the soliton shape aberrant.
讨论了光纤损耗对光孤子传输的影响，并说明当光孤子对在光纤中传播时，距离太近将会产生强烈的相互作用，导致孤子形状发生畸变。
It is pointed out that two optical solitons will strongly affect each other if they are very close, which makes the soliton shape aberrant.
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