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双语推荐:区域波前重构

以新疆南部为主要研究区域,选取2003-2010年MS>5.0典型震例进行分析,将长波辐射日值数值与历年日值数据均值相减,排除年际数据波动干扰,采用小波包方法,对均一化处理后的差值进行分解重构,发现新疆南部地区地震前小波包重构信息均有不同程度的能量衰减现象,且能量衰减时间长短与地震震级之间存在一定对应关系。该现象可以作为地震前兆异常信息参考,为地震预报提供辅助监测手段。
Chinese scholars have been searching the relationship between thermal radiation abnormity before earthquake for a long time,through a lot of example analysis research.They fully explain the feasibility of this method.In this paper,I select several more than 5 .0 magnitude earthquakes in south Xinjiang over the last ten years for analysis,and put ereryday′s long-wave radiation datum substracted the mean.This will exclude the fluctuation interference, and then I use wavelet packet to decompose and reconstruct data difference and find some degrees of energy attenuation in most earthquakes in south Xinjiang.There is some corre-spond realtion between the time of energy attenuation and the magnitude of earthquakes. These phenomena maybe serve as a kind of reference before earthquake.It also provide a new auxiliary method in monitoring earthquakes.

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针对高反射曲面零件的三维形貌测量,提出基于迭代的光栅相位偏折测量方法,通过建立相位偏折信息与工件表面梯度和高度的对应关系,采用结合区域波前重构和路径积分的三维建算法,由梯度恢复被测工件表面形貌。实验结果表明,该方法可实现对大面形或曲率较大的高反射曲面三维形貌的测量,测量范围达到150mm×150mm×20mm,测量精度约为40μm。
To solve the requirement for the 3D shape measurement of specular surface, a novel method of phase deflectormetry based on iterative strategy is proposed. The corresponding relationship between the phase deflectormetry information and the gradient and height is established. The 3D reconstruction algorithm combined zonal wave-front reconstruction and path-integration is applied to recover the profile of the parts from the gradient information. Experimental results show that this method can be used to measure the 3D shape of sepcular surface with large topography or curvature. The measurement range is 150 mm×150 mm×20 mm and the measurement accuracy is about 40 μm.
通过试验研究了不规则波浪在一陡坡(1:10)上的传播过程中的非线性特征.为达到研究目的,在试验水槽中以JONSWAP谱为靶谱生成了两组随机波浪.试验结果显示,在坡前常水深区域和坡顶,两种波况下波高分布均符合瑞利分布;但是在变浅区域两种波况的波高分布却不尽相同.应用基于小波变换的二阶相位谱来分析波浪在传播过程中的非线性相位耦合特征,结果表明:随着水深的变浅,波浪的非线性逐渐增强并且参与非线性相互耦合的频率成份也越来越多.通过二阶相位谱发现:随着水深的减小,参与最强的非线性相位耦合频率向高频处移动.另外通过傅立叶频谱、二阶谱以及二阶频谱共同分析陡坡上两组波况下低频波浪的演化情况.
This paper considers the nonlinear transformation of irregular waves propagating over a steep slope (1:10). Two experimental cases of random waves mechanically generated by JONSWAP spectra are used for this purpose. The results indicate that the wave heights in two cases obey the Rayleigh distribution both at the offshore location and on top of the slope, but, in the shoaling region, they behave different characteristic. The nonlinear phase coupling occurred within the irregular waves is investigated by the wavelet-based bicoherence. The bicoherence spectra reflect that, in the shoaling region, with the decrease of water depth, the number of frequency modes participated in the phase coupling increase, and the degree of the phase coupling enhances. In addition, the summed bicoherence shows that the frequency mode related to the local strongest nonlinear interactions shifts to higher harmonics with the decrease of water depth. This paper also investigates how the low frequency energy inc
为了提高海岸区域低频地波传播特性预测精度,研究了基于J.R.Wait及FDTD全波分析算法的罗兰-C信号海岸效应预测模型;对罗兰-C信号传播至海岸线时的电场幅度与相位的空间驻波状扰动现象进行了仿真比较;分析了突变和线性渐变两种陆海分界模型下,该扰动在近海岸区域的地/海面及其上空的分布规律,并指出该扰动存在波前倾斜现象。仿真分析表明:该研究进一步克服了J.R.Wait算法的局限,限定了驻波扰动变化量级与其在三维空间的分布范围,有助于同时提高罗兰-C系统在海岸区域地/海面及空中的导航授时精度。
In order to improve the prediction accuracy of the low frequency wave propagation charac-teristics in coastal areas,this paper makes a study of the models for predicting the coast effect in the propagation of a Loran-C signal across the coastline according to J.R.Wait and FDTD methods and a comparison of the standing wave pattern disturbances on the electric field amplitude and phase of a Loran-C signal.The analysis of sharp and linear changes in the two coastline models,disturbance va-lue,3D spatial distribution and change on the earth/sea surface and in the air are carried out.The FDTD results indicate that there is a wavefront tilt phenomenon in the disturbance.The simulation study shows that the limitations of J.R.Wait algorithm can be overcome further so as to determine the standing wave change value and 3D spatial distribution range,which is helpful to improving the navigation/timing accuracy on the earth/sea surface and in the air of the seashore.

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目的探讨隐匿性房室旁道心电图定位的临床价值。方法以我院2010年~2013年诊断收治的隐匿性房室旁道患者48例为研究对象。结果右侧旁道13例,在V1倒置12例,平坦3例,P--R间期均R-P-间期,左侧旁道35例,其中21例左前区域旁道,在Ⅰ、aVL P-波倒置,在Ⅲ、aVFP-波直立,P--R间期均R-P-间期;14例左后区域旁道,12例P-波在Ⅰ、aVL直立、浅倒置、平坦,各种变化较大,P--R间期R-P-间期,2例左后间隔旁道在Ⅲ、aVF P-波深倒置。结论隐匿性房室旁道诊断中采用体表心电图通过对P-波形态以及RP间期长短的观察能形成较为准确的定位。
Objective?To?study?the?occult?atrioventricular?bypass?the?clinical?value?of?electrocardiogram?(ecg)?positioning.?Methods?Our?hospital?in?2010-2013?of?occult?atrioventricular?bypass?patients?diagnosis?up?48?cases?as?the?research?object.?Results?On?the?right?side?of?the?bypass?13?cases,?12?cases?in?V1?inversion,?lfat?in?3,?during?the?period?between?P--R?>?R-P-interphase,?on?the?left?side?of?the?bypass?35?cases,?including?21?cases?of?left?anterior?region?of?the?bypass,?in?Ⅰ,?aVL?P-?wave?inversion,?in?Ⅲ,?aVFP-?wave?upright,?during?the?period?between?P--R? ?R-P-between?interphase,?2?cases?left?interval?after?the?bypass?in?Ⅲ,?deep?aVF?P-wave?inversion.?Conclusion?The?occult?atrioventricular?bypass?using?body?surface?electrocardiogram?(ecg)?in?diagnosis?of?P-?wave?shape?and?length?of?the?period?between?the?RP?observation?can?form?relatively?accurate?positioning.

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本文以静止卫星中波红外亮温为数据源,应用小波变换和计算功率谱方法对汶川8.0级地震和仲巴6.8级地震进行了分析研究。结果表明,这两次地震震前均出现了明显的短临热异常现象。这与长波辐射通量和热红外亮温资料的研究结果基本一致。在时间演化过程中热异常现象在震前存在一次明显的变化,这种变化有短临预测意义。地震前后热异常分布可能反映了区域应力集中和调整变化,根据异常的演化方向和异常消失区域可以估计发震的可能区域范围。
Based on the Medium Wave Infrared Brightness data of geostationary satellite, the authors applied wavelet transform and power spectrum estimation to an analytical study of thermal anomalies for Wenchuan 8.0 and Zhongba 6.8 earthquakes. The results indicate that short-term and impending thermal anomaly phenomena arose distinctly before the two earthquakes. The short-impending anomaly distributions of both earthquakes were basically consistent with the previous results of outgoing long-wave radiation and thermal infrared brightness temperature data studies. The obvious change of thermal anomaly before the two earthquakes in the time evolution has the short-term and impending significance of earthquake forecast prediction. The thermal anomalies of the two earthquakes might have reflected the changes in stress concentration and adjustment. The authors estimated the possible earthquake region according to the direction of abnormal evolution and the anomaly disappearance of the seismogenic z

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为了研究Compton散射对1维3元未磁化等离子体光子晶体中TE波禁带影响,采用Compton散射模型和传输矩阵法,进行了理论分析和实验验证,取得了一些要数据。结果表明,随着等离子体频率增大,左旋和右旋极化波禁带展宽比散射前减小0.09GHz,禁带主频率向高频区域移动增大0.48GHz。随着等离子体碰撞频率增大,两种极化波禁带宽度发生一定变化。随着等离子体回旋频率、填充率、光入射角和介质相对介电常数增大,左旋和右旋极化波禁带明显调谐效应。这一结果对等离子体光子晶体应用是有帮助的。
In order to study the effect of Compton scattering on TE wave prohibited band gaps of 1-D ternary un-magnetized plasma photonic crystals ,based on the model of Compton scattering and transfer matrix method ,some important data was obtained after the theoretical analysis and experimental verification .The broadening width of prohibited band gap of the left circle polarization wave and the right circle polarization wave were decreased 0.09GHz along with the increasing of plasma frequency after Compton scattering .The movement from the central frequency area of prohibited band gap to the high frequency area was increased 0.48GHz.The change of prohibited band gaps widths of the left circle polarization wave and the right circle polarization wave happened along with the increasing of plasma collision frequency .The significant tuning effect of prohibited band gaps of the left circle polarization wave and the right circle polarization wave was induced by Compton scattering along with the inc

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结合调频连续波(FMCW)技术的机载前视阵列合成孔径雷达(SAR)既能够获取飞机前下方区域图像,又具有FMCW体制雷达体积小、量轻的优势,易于安装在直升机等轻小型平台。前视阵列SAR的运动补偿是获得前视图像信息的关键问题之一。该文根据前视阵列SAR的几何模型,分析了载机平台运动误差对回波的影响,研究了相应的运动补偿方法。在此基础上,将补偿方法嵌入到一种基于FMCW的前视阵列SAR的改进频率变标算法(FSA)中。最后通过仿真实验验证了该补偿方法的有效性。
10.3724/SP.J.1300.2013.20067
建立理论模型,将电磁场时域有限差分方法与等离子体流体模型结合,编制一维电磁场与等离子流体耦合程序,数值研究了3 GHz高功率微波窗内外表面闪络击穿的不同物理过程.研究结果表明:外表面闪络击穿中,输出微波脉宽缩短(未完全截止),窗体前均方根场强呈驻波分布,波节与波腹位置不变,窗体外表面形成有一层高密(约10~(21)·m~(-3)量级)极薄(约mm量级)等离子体(扩散缓慢),入射波可部分透过该薄层等离子体,脉宽缩短主要源于等离子体吸收效应;降低初始等离子体密度、厚度、入射波场强及缩短入射波脉宽等方式,可不同程度地改善输出脉宽缩短效应.内表面闪络击穿中,窗体前均方根场强亦出现驻波分布f但波节与波腹位置随时间变化),等离子体向波源方向运动;强释气下,输出脉宽缩短(未完全截止),形成多丝状高密(约10~(21)·m~(-3)量级)极薄(约mm量级)等离子体区域(扩散缓慢),间距1/4微波波长,脉宽缩短主要源于等离子体吸收效应;弱释气、低场强下,脉宽缩短有所改善(但最终截止),形成多带状致密(约10~(18)·m~(-3)量级)略厚(mm-cm量级)等离子体区域(扩散较快),间距1/4波长,脉宽缩短主要源于等离子体吸收效应;弱释气、高场强下,脉宽缩短严(很快截止),形成块状高密(约10~(21)·m~(-3)量
In this paper, an electromagnetic-field FDTD method coupled with plasma fluid model is put forward to investigate the different physical phenomena of high power microwave (HPM) flashover and breakdown on inner and outer surface of output-window. Based on the above theoretical models, a one-dimensional (1D) electromagnetic field and plasma interaction code is programmed by authors. By using the code, the HPM flashover and breakdown on inner and outer surface of output-window are simulated. The numerical results could be concluded as follows. For flashover and breakdown on outer surface, output microwave pulse is shortened without cut-off; there is a standing-wave distribution of electric field RMS (Root-Mean-Square) value before the window with fixed-positions of wave nodes and antinodes;there is a ultra-high-density (~ 1021 m-3) and ultra-thin (~mm) plasma shell with slow diffusion, microwave could penetrate the plasma-shell partly; the shortening of output microwave is cau
近岸浅水区开挖深水航道造成波浪传播区域水深差异极大,势必引起波浪运动的强色散性及强非线性,用于模拟波浪传播变形的数学模型必须同时考虑两种因素的影响。建立了基于完全非线性Boussinesq方程的近岸深水航道波浪数学模型,考虑航道边坡折射、防波堤反射与绕射等因素,计算了天津港口门区波浪要素分布。研究表明:浅水区深水航道及防波堤布置对波浪分布有要影响;随入射波浪与航道角度减小,防波堤对入射波浪遮掩作用减少,进入港内波浪相对增大,但由于航道边坡的折射作用,港内最大比波高仅为0.42;直立堤反射使堤前波高可达入射波高1.3倍。研究结果可为航道布置及防波堤设计提供参考。
To-dredge-deepwater-channel-within-offshore-shoal-area-will-cause-big-difference-of-water-depth-in-wave-propagation-region,-which-will-induce-strong-dispersivity-and-nonlinearity-of-wave-motion.-The-above-two-factors-must-be-taken-into-account-simultaneously-when-a-numerical-model-is-used-to-simulate-wave-propagation-deformation.-Based-on-full-nonlinear-Boussinesq-equation,-we-established-the-wave-numerical-model-of-offshore-deepwater-channel,-which-took-the-refraction-of-channel-slope,-the-reflection-and-diffraction-of-breakwater-into-consideration,and-calculated-the-distribution-of-wave-elements-nearby-the-en-trance-of-Tianjin-Port.-The-research-results-show-that-the-deepwater-channel-and-breakwater-affect-the-wave-distribution-greatly-in-shoal-area;the-smaller-the-included-angle-of-incident-wave-to-channel,the-less-the-sheltering-effect-of-breakwater-against-inci-dent-wave,-the-higher-wave-occurred-in-port,-but-the-max-wave-height-rate-is-0.42-caused-by-the-refraction-of-channel-slo

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