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101.
本文设计了一种新型的基于无线红外通讯的电子式换人牌,通过无线红外通讯模块与单片机接口的应用,使得换人牌的显示信息由手操器无线传达。本文分析了红外通信原理,利用串行通信接口进行红外收发。设计硬件电路及相配合的软件程序,设计了震荡发生器,应用X5045进行数据存储和看门狗,应用74HC595进行数据的串入并出等。经试验证明可能够提高执场裁判员的工作效率,降低显示信息出错的几率。  相似文献   
102.
介绍了红外热成像原理及其技术特征,并对云台摄像机的预置位功能做了详细说明。在此基础上,提出了红外与可见光相结合的智能跟踪技术,该技术可准确地发现目标并跟踪目标。既实现了夜间环境下的视频监控,也克服了可见光设备检测范围的局限性。该技术可应用于学校、住宅小区等公共监控场所,从而实现智能监控和跟踪。  相似文献   
103.
Remote sensing of invasive species is a critical component of conservation and management efforts, but reliable methods for the detection of invaders have not been widely established. In Hawaiian forests, we recently found that invasive trees often have hyperspectral signatures unique from that of native trees, but mapping based on spectral reflectance properties alone is confounded by issues of canopy senescence and mortality, intra- and inter-canopy gaps and shadowing, and terrain variability. We deployed a new hybrid airborne system combining the Carnegie Airborne Observatory (CAO) small-footprint light detection and ranging (LiDAR) system with the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) to map the three-dimensional spectral and structural properties of Hawaiian forests. The CAO-AVIRIS systems and data were fully integrated using in-flight and post-flight fusion techniques, facilitating an analysis of forest canopy properties to determine the presence and abundance of three highly invasive tree species in Hawaiian rainforests.

The LiDAR sub-system was used to model forest canopy height and top-of-canopy surfaces; these structural data allowed for automated masking of forest gaps, intra- and inter-canopy shadows, and minimum vegetation height in the AVIRIS images. The remaining sunlit canopy spectra were analyzed using spatially-constrained spectral mixture analysis. The results of the combined LiDAR-spectroscopic analysis highlighted the location and fractional abundance of each invasive tree species throughout the rainforest sites. Field validation studies demonstrated < 6.8% and < 18.6% error rates in the detection of invasive tree species at  7 m2 and  2 m2 minimum canopy cover thresholds. Our results show that full integration of imaging spectroscopy and LiDAR measurements provides enormous flexibility and analytical potential for studies of terrestrial ecosystems and the species contained within them.  相似文献   

104.
南海北部油气分布的遥感探测方法研究   总被引:1,自引:1,他引:0       下载免费PDF全文
随着卫星和传感器技术的发展,遥感技术已广泛应用于油气资源调查与勘探,且发挥着越来越重要的作用。通过阐述油气烃类微渗漏模型,认为油气烃类微渗漏可以导致海表烃类气体、油膜异常及喜烃类生物聚集。并以南海北部边缘盆地为例,阐明了海洋油气遥感探测的3种方法:①利用红外波段反演海表温度异常。②利用合成孔径雷达检测海表油膜异常。③喜烃类生物的增加导致海表光谱异常,以及利用水色遥感技术检测海表微生物含量异常。最后,对海洋油气遥感的未来发展趋势进行了展望。  相似文献   
105.
为了实现红外成像制导导弹更加逼真和更加有效的仿真从而验证优化红外成像制导导弹的制导效果,研究了红外成像制导导弹飞行仿真技术;讨论了导弹飞行仿真的基本要求和红外成像制导仿真系统设计的基本原理和设计方案,提出了导弹飞行效果的一些评价指标,并利用虚拟现实仿真技术实现了一个导弹飞行可视化仿真系统;分析了仿真实验结果,实验结果表明仿真系统基本满足红外成像制导导弹飞行仿真要求,在红外成像制导导弹的科学研究中有一定价值.  相似文献   
106.
In occupational safety and health, big data and analytics show promise for the prediction and prevention of workplace injuries. Advances in computing power and analytical methods have allowed companies to reveal insights from the “big” data that previously would have gone undetected. Despite the promise, occupational safety has lagged behind other industries, such as supply chain management and healthcare, in terms of exploiting the potential of analytics and much of the data collected by organizations goes unanalyzed. The purpose of the present paper is to argue for the broader application of establishment-level safety analytics. This is accomplished by defining the terms, describing previous research, outlining the necessary components required, and describing knowledge gaps and future directions. The knowledge gaps and future directions for research in establishment-level analytics are categorized into readiness for analytics, analytics methods, technology integration, data culture, and impact of analytics.  相似文献   
107.
Herein a useful methodology to synthesize the lead zirconate titanate (PZT) nanotubes via a dip-coating deposition process with anodic aluminum oxide (AAO) template is proposed. The nano-porous AAO templates were produced using a controlled two-step electrochemical anodization technique. The PZT/AAO composite was formed using the dip-coating wetting technique. The prepared PZT precursor solution was driven into the nanopore channels of AAO template under the driving force of capillary action, subsequently the sintering process of the as-filled templates was carefully tuned to obtain Pb(Zr0.52Ti0.48)O3 nanotubes of crystalline tetragonal phase with uniform pore size and ordered arrange. Fourier transform infrared spectroscopy (FTIR) results show that in the 1200–1900 cm−1 band, the composite structure of PZT/AAO has obvious absorption peaks at 1471.56 cm−1 and 1556.09 cm−1, the absorption intensity of the composite structure is about six times of pure AAO template. The unusual optical properties found in PZT/AAO composite will stimulate further theoretical and experimental interests in ferroelectric nanostructures.  相似文献   
108.
By multi-stage rod-in-tube fiber drawing process, a single-mode fluorotellurite glass fiber was fabricated and reported for the first time. Benefiting from chemical–physical dehydration process to remove water and OH groups, the propagation loss was decreased to 1.9 dB/m at 1550 nm and the infrared window is extended from 2.8 μm to 4.2 μm, i.e. a new kind of mid-infrared glass fiber. The fiber is with a small core of 3.52 μm in diameter to meet single-mode condition, and the effective nonlinear parameter γ was estimated to be 236.7 W−1 km−1 at 1550 nm by using continuous-wave self-phase modulation method. © 2015 Elsevier B.V. All rights reserved.  相似文献   
109.
People who are totally blind or who have vevere visual impairments (e.g. less than 20/200 acuity, central macular scotomas, or advanced diabetic retinopathy) see the environment in a fashion that may be completely foreign to those who operate in a very visual fashion. For this population, the visual complexity of the environment is not a concern. What is of concern are salient features found within the environment that relate to their ability to navigate successfully in, and/or interact with, the environment as needed. Toward the purpose of representing these salient features in comprehensive form, investigators at the Atlanta Veterans Affairs Research and Development Center are employing wearable computer technology to develop a virtual environment interface. The long-range goal is to create a simplistic virtual representation of the environment that includes only features related to the current navigational task and/or interactive needs of the person. In a completed study, the use of digital infrared transmitters as beacons representing salient features of the environment was explored. The purpose of a current study now in progress is to evaluate and compare various user interface structures that were suggested by subjects during the preliminary study. The problem of interest in the current study is street-crossing; however, the results of this research should be applicable to many other problems, including identifying and locating building entrances, and identifying, locating and interacting with electronic devices such as information kiosks, automated teller machines, and self-serve point-of-sale terminals. The long-range result desired is a wearable computer with which one can easily identify and interact with a wide variety of devices in the environment via one familiar, easy-to-use interface.  相似文献   
110.
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