- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Workshop on Lunar Calibration for Satellite Remote Sensing
摘要： Tracking climate variables at the levels of precision and accuracy required to detect global change requires satellite sensors to make highly consistent measurements that can be compared to measurements made at different times and with different instruments. Gaps in climate data records, such as those resulting from launch delay or instrument failure, and inconsistencies in radiometric scales between satellites can introduce unnecessary measurement error and thus undermine the credibility of fundamental climate data records. To address these issues, leading experts in satellite remote sensing and lunar observation and modeling assembled at the National Institute of Standards and Technology from 12-15 May 2012 for a workshop to discuss the utility of and strategies for using the Moon to calibrate satellite remote sensing measurements. This report summarizes the outcome of the workshop, including suggested steps to maximize the value of the Moon as an exoatmospheric calibration source for satellite remote sensing.
关键词： lunar spectral irradiance,remote sensing,calibration,moon,radiometry
更新于2025-09-09 09:28:46
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Extending the SCOPE model to combine optical reflectance and soil moisture observations for remote sensing of ecosystem functioning under water stress conditions
摘要： A radiative transfer and process-based model, called Soil-Canopy-Observation of Photosynthesis and Energy fluxes (SCOPE), relates remote sensing signals with plant functioning (i.e., photosynthesis and evapotranspiration). Relying on optical remote sensing data, the SCOPE model estimates photosynthesis and evapotranspiration, but these ecosystem-level fluxes may be significantly overestimated if water availability is the primary limiting factor for vegetation. Remedying this shortcoming, additional information from extra sources is needed. In this study, we propose considering water stress in SCOPE by incorporating soil moisture data in the model, besides using satellite optical reflectance observations. A functional link between soil moisture, soil surface resistance, leaf water potential and carboxylation capacity is introduced as an extra element in SCOPE, resulting in a soil moisture integrated version of the model, SCOPE-SM. The modified model simulates additional state variables: (i) vapor pressure (ei), both in the soil pore space and leaf stomata in equilibrium with liquid water potential; (ii) the maximum carboxylation capacity (Vcmax) by a soil moisture dependent stress factor; and (iii) the soil surface resistance (rss) through approximation by a soil moisture dependent hydraulic conductivity. The new approach was evaluated at a Fluxnet site (US-Var) with dominant C3 grasses and covering a wet-to-dry episode from January to August 2004. By using the original SCOPE (version 1.61), we simulated half-hourly time steps of plant functioning via locally measured weather data and time series of Landsat (TM and ETM) imagery. Then, SCOPE-SM was similarly applied to simulate plant functioning for three cases using Landsat imagery: (i) with modeled ei; (ii) with modeled ei and Vcmax; and (iii) with modeled ei, Vcmax, and rss. The outputs of all four simulations were compared to flux tower plant functioning measurements. The results indicate a significant improvement proceeding from the first to the fourth case in which we used both Landsat optical imagery and soil moisture data through SCOPE-SM. Our results show that the combined use of optical reflectance and soil moisture observations has great potential to capture variations of photosynthesis and evapotranspiration during drought episodes. Further, we found that the information contained in soil moisture observations can describe more variations of measured evapotranspiration compared to the information contained in thermal observations.
关键词： SCOPE-SM model,Landsat,Evapotranspiration,Vegetation properties,Water stress,Remote sensing,Soil moisture,Vegetation functioning,Vapor pressure,Photosynthesis,Maximum carboxylation capacity,Soil surface resistance,Reflectance
更新于2025-09-09 09:28:46
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Piezoelectric effect-based detector for spectroscopic application
摘要： A stando? laser spectroscopy sensor based on a broadband tunable external cavity quantum cascade laser (ECQCL) and a piezoelectric e?ect-based detector was developed for simultaneous detection of multiple chemicals. Instead of using a standard infrared detector, a custom quartz crystal tuning fork (QCTF) with a high resonant frequency ( ～75 kHz) was adopted as a light detector for laser signal collection. To explore the capabilities of this technique, the impact of the position of incident light beam excitation with respect to the QCTF on the signal amplitude, resonant frequency and Q-factor was observed in detail. In addition, the in?uence of incident light intensity and pressure on the intrinsic property of the QCTF was also systematically investigated. Finally, the ECQCL sensor was successfully demonstrated for the stando? detection of plumes for three volatile organic compounds (VOCs) (i.e., alcohol, acetone and ether) at a distance of 40 m, which proves the applicability of the technique for the detection of leak plumes in security ?elds.
关键词： Spectroscopic applications,Quantum cascade laser,Remote sensing and sensors,Piezoelectric detector
更新于2025-09-09 09:28:46
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Assessing super-spheroids in modelling the scattering matrices of dust aerosols
摘要： Atmospheric dust particles are known to have diverse and irregular morphologies. In order to account for non-sphericity, the spheroidal model with an aspect ratio distribution has been extensively used for modeling the optical properties of dust. The spheroidal model is superior to the spherical shape assumption but it requires further improvement. In this study, super-spheroids’ modeling capabilities were systematically examined by comprehensively comparing the spheroid’s and super-spheroid’s scattering matrices. Super-spheroids have one more degree of freedom than spheroids and can be non-spherical at an aspect ratio of unity. The invariant imbedding T-matrix and the improved geometrical optics methods were employed to compute super-spheroids’ single-scattering properties with a wide distribution of aspect ratios and a number of roundness parameters. We then assessed the spheroidal and super-spheroidal models’ applicability for simulating the scattering matrices of 25 dust samples from the Amsterdam-Granada Light Scattering Database. It was found that extreme aspect ratios for spheroids in reproducing the measurements were unnecessary if super-spheroids were used. Even with equi-probable aspect ratio distribution, super-spheroids with constrained roundness parameters (from 2.4 to 3.0) could achieve better performances in concurrently matching six nonzero scattering matrix elements from the laboratory measurements. Moreover, super-spheroids demonstrated better performances than spheroids in achieving spectral consistency for modeling dust scattering matrices. Therefore, super-spheroids appear to be highly promising for atmospheric radiative transfer and remote sensing applications.
关键词： scattering matrices,super-spheroids,optical properties,radiative transfer,dust aerosols,remote sensing
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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A novel approach for estimation of residual attitude of a remote-sensing satellite
摘要： This article presents a novel approach for estimation of the residual attitude of a remote-sensing satellite based on satellite images with ancillary information and ground control points (GCPs). First, a non-linear model which translates the residual errors in roll, pitch, and yaw to scan-errors and pixel-errors in the image space is established. Subsequently, using the model and given scan-errors and pixel-errors at GCPs, an estimate of residual roll, pitch, and yaw based on the least square minimization of residuals in conjunction with the Newton’s method for non-linear optimization is proposed. A simulation is carried out to show that the estimates of residual roll and pitch are within 0.0008° (equivalent to 0.5 pixel) and the residual yaw is within 0.015° (equivalent to 0.75 pixel at the extreme ends) to its true values. The results of the article can be applied to determine the residual attitude of any remote-sensing satellite. We demonstrate our results by estimating the residual attitude based on the data-products of various Indian remote-sensing satellites. The effectiveness of the approach is shown by comparing the results with that of existing technique and it is concluded that the presented technique estimates residual attitude more accurately than the existing method.
关键词： non-linear model,remote-sensing satellite,Newton’s method,ground control points,residual attitude,least square minimization
更新于2025-09-09 09:28:46
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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 - Monitoring of Inundation Dynamics in the North-American Prairie Pothole Region using Sentinel-1 Time Series
摘要： Monitoring of wetland inundation dynamics is important for flood management and the characterisation of hydrological connectivity. SAR-based inundation extent monitoring in wetlands is often challenging due to different factors, such as waves, vegetation cover and wet snow. The presented study targets the mapping of inundation dynamics in the Prairie Pothole Region (PPR) of North Dakota, USA. A 3-year water extent time series was derived from Sentinel-1 SAR data by first delineating permanent water bodies using a clustering approach. In a second step, water body dynamics were mapped using region growing and automatic thresholding. Results suggest that there is considerable potential for mapping surface water dynamics in late spring, summer and autumn, whereas confusion with wet snow may take place in early spring.
关键词： wetlands,remote sensing,SAR,connectivity,Sentinel-1
更新于2025-09-09 09:28:46
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Subspace Multinomial Logistic Regression Ensemble for Classification of Hyperspectral Images
摘要： Exploiting multiple complementary classifiers in an ensemble framework has shown to be effective for improving hyperspectral image classification results, specially when the training samples are limited. With a different principle and based on this assumption that hyperspectral feature vectors effectively lie in a low-dimensional subspace, the subspace-based techniques have shown great classification performance. In this work, we propose a new ensemble method for accurate classification of hyperspectral images, which exploits the concept of subspace projection. For this purpose, we extend the subspace multinomial logistic regression classifier (MLRsub) to learn from multiple random subspaces for each class. More specifically, we impose diversity in constructing MLRsub by randomly selecting bootstrap samples from the training set and subsets of the original hyperspectral feature space, which lead to generate different class subspace features. Experimental results, conducted on two real hyperspectral datasets, indicate that the proposed method provides significant classification results in comparison with other state-of-the-art approaches.
关键词： Hyperspectral images,subspace multinomial logistic regression,ensemble-based approaches,remote sensing,classification
更新于2025-09-09 09:28:46
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[IEEE 2018 25th IEEE International Conference on Image Processing (ICIP) - Athens, Greece (2018.10.7-2018.10.10)] 2018 25th IEEE International Conference on Image Processing (ICIP) - Visual Saliency Analysis for Common Region of Interest Detection in Multiple Remote Sensing Images
摘要： Saliency detection is an effective tool to extract regions of interest (ROIs) from remote sensing images. However, some existing saliency detection models focus on extracting ROI from a single image, which cannot accurately detect ROI against complex background interference. In this paper, a novel visual saliency analysis and ROI extraction model is proposed to effectively extract common ROIs from remote sensing images and exclude images without ROIs. Firstly, the single saliency maps are generated by frequency-tuned (FT) method. Secondly, the cluster method based on synthesized features is proposed to group regions with similar feature into a cluster for multiple images. Thirdly, computing the mean of saliency value as the cluster saliency suppresses the saliency value of non-common ROIs. Finally, a ROI extraction method based on the maximum saliency value is proposed to extract ROIs while eliminating the image without ROIs. Experimental results indicate our model outperforms other state-of-the-art saliency detection models, achieving highest ROC and maximal PRF values.
关键词： saliency analysis,region of interest,feature clustering,Image processing,remote sensing
更新于2025-09-09 09:28:46
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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 - A Modified Wave Spectrum for Modeling in Remote Sensing Problems
摘要： In this paper we present a new directional spectrum based on both oceanological and remote sensing data. The model is compared with popular ocean wave models used for remote sensing problems of T. Elfouhaily, P.A. Hwang and V. Kudryavtsev. It is shown that the modified wave spectrum is a good choice for L band RCS modeling for moderate incidence angles. It is also shown that the modeling results with the modified wave spectrum are in agreement with experimental data. In a region after spectral peak the model is presented in a form of power-law dependency of spectral density on frequency, where power is different for different wave ranges. It allows carrying out analytical transformations easily. An asymmetrical angular spreading function is used in a spectral model.
关键词： mean square slopes,directional spectrum,remote sensing,ocean surface wave spectrum,radar cross section
更新于2025-09-09 09:28:46