衰减

We obtain several decay estimate of solutionsto hyperbolic system of first order by different norms of initial data.

得到了一阶双曲组Cauchy问题解的几个衰减估计。

There is the Cauchy problem of hyperbolic system with weak damping in Chapter4. In the space of dimension N=1,3, exploiting the semigroup method, the global existence and the decay behavior of the solution with small initial data to problem (about problem with small initial data) is put forward.

当空间维数N=1，3和初值充分小时，利用半群理论得到问题整体解的存在性，并对于整体解给出一致衰减估计；当空间维数N=1 时，利用试验函数方法讨论解在有限时刻爆破的条件。

Based on those above, the paper discusses the importance of energy in solving nonlinear wave-motion problems, which is processed from four aspects: formation of hypocenter and shock wave, energy distribution on the interface, energy attenuation in the media, and interact among waves.

通过上述认识，提出了非线性波动问题中能量的重要性，然后分别从震源与冲击波的形成，界面处的能量分配，介质中能量的衰减，波的相互作用四个方面讨论了非线性波的能量问题。

In this paper the key points discussed were that, under the condition of a sharp hypsography of desert areas of Ordos basin, we used some new geophysical methods in the investigation of surface structure to obtain high accurate surface structure data and provide reliable scientific foundation for data acquisition and process; we dealt with the optimum coupling of surface geophones and the digital realization technique in desert areas, dug into a method of high frequency compensation according to attenuations by absorption near surface, adopted data processing and correction technique, solved high frequency attenuation and geophone coupling, eliminated the influences of sharply transverse fluctuation of hypsography in desert area on the seismic data, enhanced the fidelity and SNR of seismic section, and finally picked up more geologic information on the seismic profile and improved the precision of the lateral prediction for the reservoir beds.

本文旨在研究鄂尔多斯盆地沙漠区地表变化比较大的情况下，在表层结构调查中通过应用一些地球物理新方法，以获取高精度的表层结构数据，为资料采集和数据处理提供更科学的依据；研究在沙漠区地表检波器最佳耦合的方式与数字实现技术，研究通过近地表的吸收衰减规律进行高频补偿的方法，采用数据处理校正技术，解决高频吸收及检波器耦合，消除沙漠区表层横向剧烈变化对地震资料的影响，提高地震剖面的保真度和信噪比，从而使更多的地质信息能够从地震剖面中反映出来，提高储层横向预测的精度。

The result from model show ice layer growth speed axial attenuation is larger than radial.

模拟的结果表明冰层生长速度随时间衰减的幅度轴向大于径向。

In the third chapter, we have described the effect of time-dependent couplings, and at the same time we have also thought the effect when there is decay in the system.

在第三章中，我们指出了随时间变化的耦合对两原子纠缠的影响，同时还考虑了在衰减存在的情况下的影响。

Infrasound (0.0001-20Hz) is acoustic energy with characters of little attenuation and long distance during radiation, inaudibility, diffraction and resonance in some parameters.

次声波是频率为0.0001Hz-20Hz的声波，具有传播衰减小、传播距离远、易于衍射、一般听不到、达到一定参数可引发共振等特点。

Chap. 5 deals with the influence of exciting current distribution on slow decay effect in transient EM radiation. The index theorem is modified.

然后，以行波脉冲天线为例验证了我们关于广谱辐射慢衰减以及电磁导弹形成的理论。

The relations of inducing skin current of shielding layer, core voltage and core current with the environment field were obtained. The change of shield layer current wave with grounding state of external shield and core voltage with loading resistance was analyzed. According to the dependence of shield layer current oscillating frequency on electromagnetic wave propagation velocity, conception of transporting line of shield layer-ground with equivalent relative dielectric constant was presented. fited equation of equivalent relative dielectric constant with change of cable height was given.

试验得到九芯电缆屏蔽层感应电流、芯线感应电压、芯线感应电流以及环境场之间的关系；分析了皮电流波形随外皮接地状态的变化，芯电压随负载电阻的变化；基于皮电流振荡频率与电磁波传播速度的关系，提出了屏蔽层-大地"传输线"等效相对介电常数概念，给出了等效相对介电常数随电缆高度变化的拟合式；皮电流计算与测量结果在波形、振荡周期、衰减规律等方面有较好的一致性。

Based on the current linear attenuation model and the idea of minimum arcing voltage in inductive intrinsically safe circuit , the authors establish the principle for choosing L/R ratio assuredly by using the intrinsic safety discriminant of inductive circuit and express the discharge time with known circuit parameters.

基于电感性本质安全电路放电电流线性衰减模型，引入最小建弧电压的概念，得到了放电时间不含未知参数的表达式，利用电感电路的本质安全性能判别式，确定了电感电阻比 L/R的选取原

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。