查询词典 propagation loss

The multi-material structure has a polarization dependent loss less than if the components had end surfaces normal to the direction of light propagation.

多材料结构所具的与偏振有关的损失小于组件端表面垂直于光传播方向的情况。

Based on wave analysis method, the characteristics of vibration wave propagation in typical hull structure were analyzed in consideration of wave type conversion and impedance variation in non-homogeneous structure, and the formula of sound transmission loss during incidence of plane bending wave was deduced.

以波动理论为基础，根据不均质结构中波型转换、阻抗特性，系统地分析了典型船舶结构中振动波的传递特性，推导并给出了平面弯曲波入射时的隔声量公式。

The first one is caused by electromagnetic wave refraction phenomena at air-soilinterface and the second one is caused by spherical wave propagation loss andtransmission loss.

前者主要是由于电磁波在媒质表面产生的折射效应造成的，后者主要是电磁波在传播过程中的衰减造成的，包括球面波传播损耗、媒质表面的反射损耗和有耗媒质媒质对电磁波的衰减效应。

Some of these considderationsinclude insertion loss, cross talk, propagation delay, and unterminated stubs.

需要考虑的因素包括插入损耗、串扰、传输延迟和未端接短截线。

Measurement system for crystal fiber loss has been set up, an idea that single mode quartz fiber acts as the coupler of crystal fiber incident light has been put forward. The propagation loss of the cladded crystal fiber is measured using this measurement system to be 14 times as low as that of the uncladded crystal fiber, and the transmission of low order modes has been realized in the cladded crystal fiber.

利用激光加热基座法生长出了不同直径、不同晶向的LiNbO〓和Nd：MgO：LiNbO〓单晶光纤；根据熔区质量守恒和热量守恒方程解析了生长速度、速度比和激光功率对晶纤内部显微缺陷和直径波动的影响，提出通过控制激光功率和速度比来维持熔区形状的稳定，以实现高品质晶纤的稳定生长。

Based on Douglas operators, the modified wide beam propagation is presented and the number dissipate is minimized without nearly increasing the memory and computing time. The method is also more stable and accurate than ordinary WBPM. Finally, A novel wide-angle low-loss dielectric slab waveguide Y branch is presented and analyzed by modified WBPM.

接着，本论文还分析广角BPM差分格式所具有的数值色散来源，并在不增加计算时间和内存的前提下，应用Doglas算子大大地减小数值色散带来的误差，提高了计算精度，提出了改进的WBPM，而且还发现这种方法有具计算稳定的优点。

In order to solve the problem,an exponential expression similar to that of the electromagnetic wave propagation loss is used to describe change of observation weight with distance,and the standard statistics retrieval algorithm is used to test the effect of retrieval speed and precision caused by different observation weight.

赵小峰 解放军理工大学气象学院，南京 211101提出采用一种与电磁波传播损耗相类似的指数衰减形式来描绘观测值权重随距离的变化，结合标准的统计反演算法来测试不同的观测值权值对反演速度与精度的影响。

This system ofcompatible electromagnetism of frequency spectrum has someimportant functions listed as follows:(1) Analysis disturbance of the same or adjacent frequencies (2) Analysis of performance of radio link (3) Analysis of intermodulation (4) Automatic selection of frequency(auxiliary assignment of frequency)(5) Prediction of region of radio field intensity (6) Harmonization of frequency border (7) Analysis and design the system of microwave and satellite earth station.(8) Generate photographs This paper realizes the function of harmonization analysis ofthe system of microwave and satellite earth station. The concretework includes:(1) Based on the propagation model of radio wave,computing the absorption loss of atmosphere of microwavecommunication system and its fading, simulating the receivingvoltage and realizing the computation of disturbance andharmonization between microwave station and earth station.

频谱电磁兼容分析系统主要实现以下几个功能：⑴同、邻频干扰分析⑵无线链路性能分析⑶互调分析⑷频率自动选择⑸场强覆盖预测⑹边界协调⑺微波与卫星地球站系统设计和干扰协调分析⑻图形制作功能本文做为全省建设的电磁兼容分析系统的一部分，实现了微波站与地球站干扰协调分析这一功能，具体有：⑴以无线电波自由空间传播为模型，对微波通信系统的大气吸收损耗和衰落储备量进行了计算、对接收电平进行了模拟仿真，实现了微波- I -吉林大学硕士学位论文 Abstract站与地球站之间的干扰与协调计算。

The main contents are as follows:Firstly, starting with the general situation of soil erosion and the harms caused by it, the causes leading to the local soil erosion problem are analyzed comprehensively in the paper. And connecting with the measures taking place, sticking points towards the career of soil and water conservation are expatiated upon.Secondly, Back-Propagation Neural Network, One of Artificial Neural Network is used to set up a modal about the connection of the soil erosion modulus and seven factors impacts on it, such as, rainfall, rainfall largest intensity in 30 minutes, runoff coefficient, vegetation cover percent, rate of granule, rate of physical viscidity-clay, the rate of organic matter. Through the comparison with linear regression model, the second regression model, the Chinese Soil Loss Equation, it illustrated that BP Neural Network modal is more accurate than the other three modals in forecasting the mount of soil erosion, and the BP Neural Network will have some applicability in forecasting in soil erosion.

本文以霍山县作为皖西大别山区的典型区域，主要研究了以下内容：(1)从介绍霍山县土壤侵蚀状况以及所造成的危害入手，全面分析了导致当地土壤侵蚀发生的原因，并结合当地采取的水土保持相关措施，阐述了当地水土保持工作的症结所在；(2)结合上土市水土保持试验站多年实测资料和2005年实验资料，应用BP神经网络理论，建立了次降雨土壤侵蚀量与次降雨量、最大30min雨强、径流系数、植被覆盖度等因子之间关系的模型，并通过BP神经网络的预测模型与一次回归模型、二次回归模型、CSLE模型之间的对比分析，说明了建立的BP神经网络模型在土壤侵蚀预测可以取得较回归模型和CSLE模型更高的精度，也说明了BP神经网络理论在土壤侵蚀预报中具有一定的适用性。

The model of photon-induced refractive index change based on GaAs materials is presented briefly, then the model based on GaAs/AIGaAs quantum wells materials is deeply analyzed by treating the effects of photon-excited carriers self-consistently. Furthermore, the propagation characteristics of multi-quantum well waveguide is invested, and the low-loss multi-quantum well rib waveguide deeply etched is also designed by using the spectral index method.

在简要分析了基于GaAs材料的光致折射率模型的基础上，通过自洽的方法，重点研究了基于GaAs/AlGaAs多量子阱材料的光致折射率模型；其次分析了量子阱波导传输特性，利用谱折射率法设计低损耗的深刻蚀脊形量子阱波导。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。