冰川冷暖谁先知(下)

冰原:陆地上其厚度不足以掩盖冰下地形之起伏的毯状冰体,规模次于大陆冰盖。冰缘:原指冰川边缘地区,现已泛指不被冰川覆盖的气候寒冷地区,大体与多年冻土分布范围相当,所以冰缘地貌又称冻土地貌。     

外语听力考试发射系统介绍

本文主要介绍近年来出现各种听力考试的播放方法，并分析了这些方法的优缺点。     

红外传输特性在照明节能上的研究与应用

红外技术在生产生活中的应用是很广泛的.红外线也可以进行数据传输,但是局限性较大.我们转变思路利用红外线对障碍物等干扰的敏感,以其作为探测手段,设计成探测器并应用于节能系统,实现智能节能.     

Application of NIR spectroscopy for firmness evaluation of peaches

The use of near infrared （NIR） spectroscopy was proved to be a useful tool for quality analysis of fruits. A bifurcated fiber type NIR spectrometer, with a detection range of 800-2500 nm by InGaAs detector, was used to evaluate the firmness of peaches. Anisotropy of NIR spectra and firmness of peaches in relation to detecting positions of different parts （including three latitudes and three longitudes） were investigated. Both spectra absorbency and firmness of peach were influenced by longitudes （i, ii, iii） and latitudes （A, B, C）. For modeling, two thirds of the samples were used as the calibration set and the remaining one third were used as the validation or prediction set. Partial least square regression （PLSR） models for different longitude and latitude spectra and for the whole fruit show that collecting several NIR spectra from different longitudes and latitudes of a fruit for NIR calibration modeling can improve the modeling performance. In addition, proper spectra pretreatments like scattering correction or derivative also can enhance the modeling performance. The best results obtained in this study were from the holistic model with multiplicative scattering correction （MSC） pretreatment, with correlation coefficient of cross-validation γcv=0.864, root mean square error of cross-validation RMSECV=6.71 N, correlation coefficient of calibration r=0.948, root mean square error of calibration RMSEC=4.21 N and root mean square error of prediction RMSEP=5.42 N. The results of this study are useful for further research and application that when applying NIR spectroscopy for objectives with anisotropic differences, spectra and quality indices are necessarily measured from several parts of each object to improve the modeling performance.     

基于Adriano控制器的寻线智能车设计

以飞思卡尔模型C车为车载平台,基于Adriano开发环境,采用红外线传感器进行路径检测,设计了一种寻线智能车.该智能车主要包括微控制器(MCU)模块、电机及驱动模块、舵机模块、路径识别模块.通过系统软、硬件的调试,小车能够稳定的沿引导轨迹运行,行驶效果良好,验证了系统设计可行性.     

破解响尾蛇导弹的奥秘

响尾蛇,是一种凶猛的毒蛇。响尾蛇的捕食方法与众不同,它是以特殊的红外感应系统捕食猎物的。红外线是一种电磁波,当物体温度高于绝对零摄氏度时会产生红外线。在电磁光谱中,红外线介于可见光与无线电波和雷达波之间,能透过非金属物质传至外界。响尾蛇一旦发现可疑红外线,就会迅速跟踪,然后迅速作出决断。一旦它觉得是可口的猎物,就会迅速发动袭击。     

眨眼睛就能操控电器的耳朵开关

这种叫做“耳朵开关”的小玩意儿，外观和一般耳机无异，但它内建一组红外线感应器，能侦测耳朵内部因 表情变化产生的微小动作。使用者只要伸个舌头，就能开关iPod（音乐数码播放器）。眼睛睁大，就可以跳到下一首歌；眨眨右眼，就能回到上一首。使用者也能自定各种不同表情的程序，例如扭鼻子或微笑。     

无线局域网的组网及其联网方式

无线局域网是计算机网络与无线通信技术相结合的产物。无线局域网的基础还是传统的有线局域网，是有线局域网的扩展和替换。它只是在有线局域网的基础上通过无线集线器、无线访问节点、无线网桥、无线网卡等设备使无线通信得以实现。与有线网络一样，无线局域网同样也需要传送介质。只是无线局域网采用的传输媒体不是双绞线或者光纤，而是红外线或者无线电波，且以后者使用居多。