探测的

Measuring weak absorptance of thin film coatings by surface thermal lensing technique.

表面热透镜技术探测光学薄膜的微弱吸收。

In this thesis, several key technologies of passive acoustic direction are studied.

本文针对被动声探测中若干关键技术，进行了深入的研究。

The results showed that:(1) The characteristic frequency of IC neurons of house mouse was increased with increasing recording depth, and the masker intensity used was positive relevant to the IC neurons\' minimum threshold. When the minimum threshold was high, the masker intensity needed was loud, vice versa.(2) According to the masking rate at MT+10dB of IC neurons to frequency modulation and tone burst, the IC neurons were classified as three types: type I neurons ( 72/113, 63.7%), in which the masking effect of TB was better than frequency modulation ;type II neurons (32/113, 28.3%), in which the masking effects of the two maskers were same; type III neurons( 9/113, 8.0%), in which the masking effect of FM was better than TB.(3) Type I neurons, the minimum threshold of which was low, but the Q_(10) and DR values of which were large; in type III neurons, the minimum threshold was high, the Q_(10) and DR values were narrow; in type III neurons, the MT Q_(10) and DR values were in between.(4) Both FM and TB could make the MT of type I neurons shift upward distinctively, but the effect of TB was more significant than FM.(5) The Q_(10) values of type I neurons became narrower under the influence of TB, were unaffected under the influence of FM.

结果显示：(1)小鼠下丘神经元的特征频率随着记录深度的增加而增高，掩蔽声强度与神经元的最小阈值呈正相关，即对高最小阈值的神经元进行掩蔽时需要的掩蔽声强度高，对低最小阈值神经元进行掩蔽需要的掩蔽声强度低：(2)根据调频声(frequency modulation， FM)和短纯音(tone burst， TB)对下丘神经元阈上10dB处反应的掩蔽，将小鼠IC神经元分为三类：Ⅰ类神经元(72/113，63.7％)，短纯音的掩蔽效果比调频声更好；Ⅱ类神经元(32/113，28.3％)，两者对神经元声反应的掩蔽率相同；Ⅲ类神经元(9/113，8.0％)，调频声的掩蔽效果更好；(3)Ⅰ类神经元的最小阈值低、Q_(10)值和动态范围大，Ⅲ类神经元最小阈值高、Q_(10)值和动态范围小，Ⅱ类神经元的最小阈值、Q_(10)值和动态范围介于Ⅰ和Ⅲ类神经元之间；(4)短纯音和调频声都可以使Ⅰ类神经元声反应的最小阈值明显上移，但短纯音使神经元最小阈值的上移更显著：(5)短纯音使Ⅰ类神经元的Q_(10)值变小，调频声使神经元的Q_(10)值增大不显著，短纯音与调频声对神经元Q_(10)的影响差别显著；(6)短纯音与调频声都使神经元的动态范围减小，并且作用显著，但短纯音的效果更显著：(7)短纯音与调频声都使神经元反应的潜伏期延长，效果显著，但TB的延长作用更为显著；(8)随着探测声强度的升高，短纯音和调频声对Ⅰ类神经元声反应的掩蔽率都降低，但在各个探测声强度短纯音的掩蔽率都比调频声高。

This project was established based on the first cooperative development of optical in situ real time detecting technique probing the atomic scale layer-by-layer epitaxy growth of oxide film. Over the last three years, we have given full play to the advantages and characteristics of both sides and have finished the assumptions and plans of this subject satisfactorily. 1. In Institute of Physics, we set up advanced oblique-incidence reflectivity difference equipment and wrote one data acquisition procedure that made the simultaneous detection of optical signal and RHEED signal into reality. 2. The first observation of sustained oscillations over hundreds of monolayers in both real and imaginary signals during the epitaxy growth of SrNb0.1Ti0.9O3 on SrTiO3 substrate in LMBE testifies that oblique-incidence is an excellent method to detect and monitor film epitaxy growth real time. 3. For the first time, we verify that oblique-incidence reflectivity difference method can be used to monitor the layer-by-layer growth mode during continuous growth through the correspondence between optical signals to atomic or molecular step edge density on the growth surface. 4. Phenomenological analysis shows that optical signals comprise three parts, the first is proportional to the average thickness of the film and depends on the bulk phase dielectric response; the second is proportional to the coverage of terraces and depends on the dielectric response of atoms or unit cells in the terrace; the third is proportional to the coverage of step edges and depends on the effective dielectric response of atoms or unit cells at step edges. This makes oblique-incident reflectivity difference technique a quantitative macroscopic method to monitor film growth.

中文摘要：本课题是在合作首次发展了氧化物薄膜原子尺度层状外延生长光学原位实时探测方法的基础上立项的，三年来，我们充分发挥双方的优势和特点，圆满完成了课题的设想和计划。1、在物理所建立了一套先进的光反射差法装置，编写了计算机系统的数据采集程序，实现了两路光学信号和RHEED数据的同步采集和显示。2、用激光分子束外延在SrTiO3基底上生长SrNb0.1Ti0.9O3薄膜，首次观测到连续外延几百个原胞层，周期振荡的光反射差实部和虚部信号，证明了光反射差法是一种能原位实时探测与监控薄膜层状外延生长的好方法。3、首次验证了通过对生长表面原子或分子台阶密度的响应，光反射差法可用于原位实时监测在连续生长条件下薄膜的层式生长模式。4、通过唯象理论的研究，证明光反射差信号由三项组成，第一项只与薄膜的平均厚度和宏观光学电介质常数有关；第二项与分子台阶面覆盖度和台阶面上分子层的光学电介质常数有关；第三项与台阶边缘的覆盖度成正比，并和在台阶边缘的分子的有效光学介电常数有关。

Because of the existence of natural detecting blind area o f general radar on detecting flying object flying in veryˉ low altitude, it is so essential to put forward a suspended bomb t heory which would make use of sound wave's characˉ teristic parameters as its wavelength and spectrum to get the obje ct's direction and position, and to discuss its orientaˉ tion method and embattle model.

由于现有的常规雷达探测超低空飞行的来袭兵器有其固有的盲区，作为雷达的必要补充，利用声音的大小、频谱等特征能够反映声源的方位等特征参数的特性，提出了一种被动声学探测悬浮弹理论，并对其定位算法和布阵模式进行探讨，目的是防御拦截低空超声速巡航导弹。

In view of the facts that traditional graphical construction has less pertinence to stray light and tracing different incidence angle rays is fatiguesome and more likely to omit some rays, we proposed a reverse ray-trace method based on the ray reversibility. According to the method, a dot-matrix source was set at the image plane. Each dot emitted rays to fully cover the system aperture. A detector surface, large enough to receive all possible rays from the source, was set at object plane.

针对传统作图法设计遮光罩的针对性不强，且追迹不同入射角的光线繁琐、容易遗漏的问题，本文提出一种逆向追迹法，依据光的可逆性，在像面处设置点阵面光源，每一点都发出充满系统孔径的光束，在物面设置足够大的探测面，使之有充足的余量记录所有到达物方的光线，利用该方法可以在探测面上直观地区分出非成像杂散光。

The invention discloses an optical-fiber all-optical code converter, comprising a temperature control circuit as well as optical-fiber Mach-Zed interferometer, heat sink, semiconductor refrigerator, thermosensitive resistor and radiator, where the interferometer is composed of two cascaded 3dB couplers on the heat sink, the relation between length difference delta L of two arms of the interferometer and generated delay time difference delta T is that delta L=c.delta T/n, where c is light velocity in vacuum and n is refractive index of optical fiber; the thermosensitive resistor is used to detect temperature of interferometer, the temperature control circuit is used to compare feedback voltage of the thermosenstive resistor with a given voltage to regulate working current of the semiconductor refrigerator, and the semiconductor refrigerator refrigerates or heat two arms of the interferometer by the heat sink.

本发明公开了一种光纤型全光码型转换器，它包括温控电路和位于密封盒内的光纤型马赫-泽德干涉仪、导热热沉、半导体制冷器、热敏电阻以及散热片；干涉仪由位于导热热沉上的二个3dB耦合器级联而成，两臂的长度差ΔL与产生的延时差ΔT之间的关系为ΔL＝c。ΔT/n，c为真空中光速，n为光纤折射率；热敏电阻用于对干涉仪的温度进行探测，温控电路用于比较热敏电阻反馈的探测电压和设定电压，对半导体制冷器的工作电流进行调节，半导体制冷器通过导热热沉对干涉仪两臂同时进行制冷或加热。

The idea is that, in the event of a collapse, survivors able to reach one of the plates would bash it to create vibrations that are detected by a string of geophones, standard devices used to measure seismic activity, placed on the surface along the line of the mine.

这种想法就是在塌陷的事故中幸存者能够到其中的一个铁板猛烈的敲它制造可以被地音探测器系列探测到的振动，这些标准的用来探测地震的探测器是沿着矿的脉络放的。

The invention relates to a method of detecting an internal arc in a metal-clad electrical link, wherein the rising edge of the internal pressure surge generated by the arc and propagating inside the cladding is detected at a fixed location along the cladding.

一种探测铠装的电接线（11）中的内电弧的方法，其特征在于在沿着包层（11）的固定位置探测由电弧产生并在所述的包层（11）内扩展的内压力骤增（6）的上升边缘（5）。

We consider suburban areas in terms of population density and of apparent spectral reflectance using Landsat data and quantify the relationship between the two variables. We also compare these results with the USGS National Land Cover Dataset (National Land Cover Characterization, 2001). We selected the Low Intensity Residential, High Intensity Residential and Commercial/Industrial/Transportation classes and crossreferenced the areal extents for these classes with vegetation fractions and urban classification estimates for the six cities included in this study.

我们从人口密度方面和利用美国地球资源探测卫星数据的表现光谱反射比与确定两变量间的关系来考虑郊区，另外，为了对该研究中的六个城市做出评价，我们将这些探测研究结果与美国地质勘探局的国家地表的一套数据(2001国家地表特点)相比，收集低密度住宅，高密度住宅，商业工业运输的分类，通过植被区与城市分类交叉引用这些来自同一地区的廷区。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。