- 标题
- 摘要
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- 实验方案
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A broadband cavity enhanced absorption spectrometer for aircraft measurements of glyoxal, methylglyoxal, nitrous acid, nitrogen dioxide, and water vapor
摘要： We describe a two-channel broadband cavity enhanced absorption spectrometer (BBCEAS) for aircraft measurements of glyoxal (CHOCHO), methylglyoxal (CH3COCHO), nitrous acid (HONO), nitrogen dioxide (NO2), and water (H2O). The instrument spans 361–389 and 438–468 nm, using two light-emitting diodes (LEDs) and a single grating spectrometer with a charge-coupled device (CCD) detector. Robust performance is achieved using a custom optical mounting system, high-power LEDs with electronic on/off modulation, high-reflectivity cavity mirrors, and materials that minimize analyte surface losses. We have successfully deployed this instrument during two aircraft and two ground-based field campaigns to date. The demonstrated precision (2σ) for retrievals of CHOCHO, HONO and NO2 are 34, 350, and 80 parts per trillion (pptv) in 5 s. The accuracy is 5.8, 9.0, and 5.0 %, limited mainly by the available absorption cross sections.
关键词： broadband cavity enhanced absorption spectroscopy,water vapor,nitrous acid,methylglyoxal,aircraft measurements,glyoxal,nitrogen dioxide
更新于2025-09-09 09:28:46
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[Energy, Environment, and Sustainability] Sensors for Automotive and Aerospace Applications || Corrosion Monitoring and Control in Aircraft: A Review
摘要： There has been increasing trend for health monitoring of an aircraft to deal its life issues and to minimize the operational cost. The corrosion is one of the important factors which limits the life of an aircraft due to material loss and fatigue cracking. The development of corrosion monitoring systems and models can provide the solution for health monitoring and prediction for remaining life of an aircraft. This chapter provides a comprehensive review on different types of corrosion, corrosion monitoring, and corrosion control. The latest studies on aircraft corrosion have been discussed in chapter. The different techniques based on nondestructive testing methods such as ultrasonic, electromagnetic, radiographic, thermographic have been detailed out in the chapter. Further for corrosion control, different schemes of corrosion control and coating removal techniques have been discussed in detail.
关键词： Monitoring,Aircraft,Health,Corrosion control
更新于2025-09-09 09:28:46
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[IEEE 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Novosibirsk, Russia (2018.10.2-2018.10.6)] 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Modern Tendencies in the Development of Airborne Synthesized Aperture Radars for Remote Sensing of the Earth
摘要： The article is an overview of the development trends of aviation synthetic aperture radars, including information on new systems created in the world and Russia. It describes main technical features of the prospective radar and tasks to be solved for them.
关键词： unmanned aerial vehicle,remote sensing,light aircraft,airborne micro navigation system,Synthetic aperture radar,high resolution radar
更新于2025-09-09 09:28:46
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Development of a Multispectral Albedometer and Deployment on an Unmanned Aircraft for Evaluating Satellite Retrieved Surface Reflectance over Nevada’s Black Rock Desert
摘要： Bright surfaces across the western U.S. lead to uncertainties in satellite derived aerosol optical depth (AOD) where AOD is typically overestimated. With this in mind, a compact and portable instrument was developed to measure surface albedo on an unmanned aircraft system (UAS). This spectral albedometer uses two Hamamatsu micro-spectrometers (range: 340–780 nm) for measuring incident and reflected solar radiation at the surface. The instrument was deployed on 5 October 2017 in Nevada’s Black Rock Desert (BRD) to investigate a region of known high surface reflectance for comparison with albedo products from satellites. It was found that satellite retrievals underestimate surface reflectance compared to the UAS mounted albedometer. To highlight the importance of surface reflectance on the AOD from satellite retrieval algorithms, a 1-D radiative transfer model was used. The simple model was used to determine the sensitivity of AOD with respect to the change in albedo and indicates a large sensitivity of AOD retrievals to surface reflectance for certain combinations of surface albedo and aerosol optical properties. This demonstrates the need to increase the number of surface albedo measurements and an intensive evaluation of albedo satellite retrievals to improve satellite-derived AOD. The portable instrument is suitable for other applications as well.
关键词： UAS,UAV,MODIS,albedo,LANDSAT,drone,satellite remote sensing,AOD,unmanned aircraft system
更新于2025-09-04 15:30:14
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Influence of Cosine Corrector and Uas Platform Dynamics on Airborne Spectral Irradiance Measurements
摘要： Measuring solar-induced chlorophyll fluorescence from small-sized Unmanned Aircraft Systems (UAS) can potentially fill the scaling gap between ground-based and airborne/space-borne observations. These measurements require well calibrated, high-spectral resolution spectroradiometers and precise measurements of vegetation radiance and incoming solar irradiance. Here we present a system equipped with a spectroradiometer with a split optical path that measures incoming irradiance through a cosine corrector/diffuser. The objectives of this study are to characterise cosine corrected solar irradiance measurements with regard to sensor homogeneity and possible offset from an ideal cosine response. We further suggest a methodology to calculate a corrected zenith angle that accounts for changing sensor orientation due to pitch, roll and heading of the UAS platform during flight. We found that the cosine corrector is sufficiently homogeneous, thus measurements are independent of UAS heading. The response follows the cosine law for zenith angles, however, the sensor significantly underestimated irradiance for zenith angles >10?, with overall cosine errors ranging from 0.991 to 1.229. Yet, typical in-flight platform pitch and roll angles produce a zenith angle offset of up to 6? in low wind conditions. Cosine sensor measurements corrected for the zenith angle offset and the cosine error resulted in a 1.7% change in irradiance.
关键词： irradiance cosine corrector,spectroradiometer,sun zenith angle,solar-induced chlorophyll fluorescence,unmanned aircraft system
更新于2025-09-04 15:30:14
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Active Cancellation of Bistatic Scattering of Large Aircraft Using Conformal 4-Port Magnetic Antenna
摘要： Possibilities of the active cancellation of bistatic radar cross section (RCS) of the large aircraft (LA) with help of stealth conformal 4-port magnetic antenna (MA) is considered. The antenna is located in the upper part of the fuselage of an aircraft in a niche under the radar absorbing radome. The antenna is simulated in the form of loop, three-layer ferrite core with four single-turn coils and with excitation ports (in the modes of radiation and scattering). The effect of excitation of the ports on radiation patterns and the cancellation of bistatic RCS of LA?MA system in the range of 10 to 30 MHz is studied. It is shown that the smart inclusion of two or four ports of the active MA in the stealth-mode provides of the deep reduction (more 40 dB relative to aircraft RCS without antenna) of bistatic total RCS in the given angular sectors of observation.
关键词： active cancellation,conformal antenna,ferrite core,large aircraft,radar cross section,magnetic antenna
更新于2025-09-04 15:30:14
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - The Use of a Quadcopter-Mounted Hyper-Spectral Spectrometer for Examining Reflectance in Scottish Coastal Waters
摘要： Remote sensing of the marine coastal environment is useful for obtaining information about processes occurring within it. Monitoring has traditionally been carried out in situ, before investment increased in remote techniques such as manned planes and satellites. This paper proposes the use of remotely piloted aircraft systems (RPAS) as an alternative platform, with an aim of increasing the spectral, spatial and temporal resolution of data whilst reducing the associated costs and risks. A custom-built ‘spectro-copter’ system, comprising of an integrated dual field-of-view, miniaturised, hyper-spectral spectrometer aboard a purpose-built quadcopter is presented, developed at the Scottish Association for Marine Science (SAMS), Oban. This has been produced with a view to investigating reflectance from Scottish coastal waters, which can give inferences as to the concentrations of various constituents present [1, 2]. Initial test flights show the ‘spectro-copter’ system is capable of flights of ~20 minutes, sufficient for meaningful data collection, despite late adjustments incurring increased weight and an associated reduction in efficiency. Early results demonstrate that the setup is capable of discerning differences in R at a high spectral resolution. Further work is ongoing in order to assess the capacity for establishing this equipment as a routine technique for the monitoring of coastal harmful algal blooms (HAB), which currently relies upon physical sampling in combination with satellites. HAB events are noted to be increasing in severity and frequency [3, 4], with knock-on health and economic impacts, particularly for the rising aquaculture industry in Scottish coastal waters [5]. Therefore advancement of an alternative, affordable technique would be extremely beneficial.
关键词： spectrometer,Scottish coastal waters,reflectance,remote-sensing,quadcopter,remotely piloted aircraft system,hyper-spectral
更新于2025-09-04 15:30:14