查询词典 spectrum analysis

The visible spectrum of Mg-based alloy was studied with grating spectroscope and prism spectroscope based on simulated spectrum.

在计算机模拟基础上使用光栅看谱镜和棱镜看谱镜对镁合金基体及成分元素的可见光谱进行了分析，摄制了彩色图谱，研究了镁合金看谱分析方法。

This solution uses DSSS technology in wireless transceiver, and works in 2.4GHz ISM band. The author first analyzed spread spectrum technology that is used extensively in short-range wireless communications, and discussed some pseudo noise codes" application in spread spectrum technology. Then it gave wireless transceiver"s detailed block diagram in the physical layer.

本系统在无线收发部分采用DSSS技术，工作在2.4GHz ISM频段，本文首先介绍了在短距离无线通信中广泛应用的扩频技术，讨论了几种伪随机码在扩频通信中的应用，然后给出了本系统中物理层所用的硬件电路的框图，介绍了所用芯片组的原理。

Basic characteristics of cosine transform spectrum were analyzed, where contour lines of 2D cosine transform of point mass present the shape of a quarter of concentric circles and the number of counter become small along with the increasing of wave numbers. The spectrum of vertical rectangularcylinder put up periodic zero counters which mark off quadrate areas, the values of counter in each areas alternately change between the plus and the minus, and with the increasing of wave number, the values of counter present attenuation character alike e exponent.

分析了点质量和直立矩形柱体重力异常余弦变换谱的基本特征：点质量二维余弦变换谱等值线呈1/4同心圆形状，等值线随着波数的增大而变稀；直立矩形柱体谱出现了周期性变化的零等值线，该等值线将非零等值线划分为a×b个矩形区域，而且等值线值在各矩形型区域中正负交替变化，随着波数的增大，不同的矩型域中等值线值呈e指数衰减特征。

Some results about the re-emission spectrum , the re-emission flux, the albedo and the equivalent temperature at the boundary are given, and the variations of re-emission spectrum with the incident flux are analyzed.

利用一维多群辐射输运程序，数值研究了平面Au靶入射流强度对再发射谱、再发射流、反照率及边界等效温度的影响。

Some results about the re-emission spectrum, the re-emission flux, the albedo and the equivalent temperature at the boundary are given, and the variations of re-emission spectrum with the incident flux are analyzed.

当入射流强度在（0.12-1.2）×1014Wcm2范围内，发射谱接近平衡谱，但在峰值附近谱形发生畸变。随着入射流强度降低，发射谱偏离平衡谱越来越大。分析表明，这与烧蚀深度和冕区光学厚度变小有关。

Some results about the re-emission spectrum,the re-emission flux,the albedoand the equivalent temperature at the boundary are given,and the variations ofre-emission spectrum with the incident flux are analyzed.

当入射流强度在(0.12-1.2)×1014Wcm2范围内，发射谱接近平衡谱，但在峰值附近谱形发生畸变。随着入射流强度降低，发射谱偏离平衡谱越来越大。分析表明，这与烧蚀深度和冕区光学厚度变小有关。还给出了在不同入射流强度情况下反照率及边界等效温度随时间变化规律和对吸收流及再发射流脉冲的分析。

Under an appropriate condition, the squeezed vacuum field can trap the two atoms inri.An analytical expression of emission spectrum for three-level atom interacted with two-mode cavity field is given. The effects of the initial state of system on the emission spectrum for three-level atom are explored.

我们给出了好腔中与双模腔场相互作用的三能级原子发射谱的一般表达式，探讨了系统初态对三能级原子发射谱的影响，阐明了只有原子和双模驱动场初始时刻均处于相干叠加态，原子不同跃迁通道间的量子干涉才使得原子发射谱呈现相位敏感性。

In the last new years , as the demands of wireless communication system grows rapidly , the bands of microwave frequency had been saturated with various communication applications . To achieve wider spectrum for high-speed and high-capacity transmission , bands of millimeter-wave frequency are the solution of this problem . The advantage of MMW wireless communication systems is wider bandwidth comparing with microwave communication systems . To utilize the spectrum efficiently , many methods of complexly digital modulation is proposed . The more complex modulation , the higher linearity is required , and more various phase of signals are required to accomplish process of modulation . Therefore high-linearity and quadrature-phase modulator and demodulator are the emphasis of this thesis . For high level of integration , high performance and low cost , this chip is fabricated by the complementary oxide semi-conductor 0.13um process . A compact size of direct down-conversion and direct up conversion circuits will be presented in this thesis .

近年来随著无线通讯产业的蓬勃发展，微波频带已经趋近於饱和，为了追求更宽的频谱来达到更快传输速率及高资料容量的传输，宽频的毫米波频段提供了解决此问题的途径，毫米波无线通讯系统提供了相对於微波通讯系统宽频的优点，且为了更有效的使用频谱，各种不同且复杂的数位调变方式及方法被发表出来，越复杂的调变方式其所需的线性度越高，且需要更多不同的相位讯号来完成调变的过程，因此高线性度及四相位的调变及解调器将是此篇论文的研究重点，为了达到高整合性，高效能，及低成本的电路设计，我门利用互补式金氧半导体制程来完成此电路设计，因此一小面积的直接降频(Direct down-conversion)及直接升频(direct up-conversion)电路将在文中介绍。

In overlay cognitive radio, secondary users harness unused spectrum bands for their transmission; in underlay cognitive radio, an ultra-wideband transmission with very low power spectrum density is employed by the secondary user to minimize harmful interference to the primary users.

认知无线电和动态频谱接入网络因此应运而生，成为近期无线通信和网络研究的热点。通常的认知无线电技术主要采用两种频谱接入方式：Overlay和Underlay。

The type-spectrum-chart of tow-row planetary gear train is plotted. Discussing the two examples in the type-spectrum-chart, two schemes of the five-shift transmission are obtained.

用约束矩阵形成挡位矩阵，分别针对型谱中一元联结和二元联结2种方式的结构型式实例进行传动分析，得到2种五挡双排行星齿轮变速机构的结构方案。

The teacher likes the honeymouthed little girl very much.

老师很喜欢这个嘴甜的小姑娘。

Mr. Notker Bien's interests are traveling, spending quality time with the family and long-distance-running.

诺特卡·柏恩先生热爱旅游，长跑，以及和家人一起共度美好时光。