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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 - Validation of the Surface Energy Balance Retrieved From Remote Sensing Data For the Metropolitan Area Of Rio De Janeiro (MARJ)
摘要： The knowledge of the energy balance is critical to the understanding the urban thermal behavior. Advances in quantitative remote sensing showed that the energy fluxes can be retrieved from imagery data. However, every product generated from remote sensing must be validated. In this context, this study retrieved the fluxes from the energy balance and validated them with in-situ data. The fluxes were based on the Surface Energy Balance Algorithm for Land (SEBAL) and Landsat-8 images, for comparison with a micrometeorological station located in the Fund?o Island-RJ. The Bowen ratio and eddy covariance methods were used to obtain the in-situ fluxes from the station data. The retrieved SEBAL fluxes were closer to the Bowen ratio than eddy covariance method. As energy fluxes present themselves as turbulent fluxes, much remains to understand their behavior and the accuracy of algorithms based on remote sensing data over urban surfaces. The work is a contribution to improve our knowledge about these surface fluxes in urban environments.
关键词： SEBAL,Validation,LANDSAT
更新于2025-09-10 09:29:36
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DETERMINATION OF THIAMINE HCL (VITAMIN B1) AND PYRIDOXINE HCL (VITAMIN B6) CONTENT IN TABLET BY FTIR
摘要： The combination of thiamine hydrochloride (vitamin B1) with pyridoxine hydrochloride (vitamin B6) has been efficacious to help the metabolism of carbohydrates and amino acids. FTIR (Fourier transform infrared) is a technique widely used in compound identification and determination of functional groups but rarely used for the quantitative purposes. This study aims to obtain a analysis determination method of this vitamin combination simultaneously in tablet dosage form using FTIR. Amount of vitamin B1 and B6 standard were mixed with KBr crystal in a series of concentration (% w/w) in kalium bromide (kbr) crystal, then measured with FTIR. These spectrums yielded were transformed into an absorbance afterward changed to its derivative. The finest spectrum, which showed the best specificity and linearity, was selected and its area under the curve was calculated. The other validation parameters: accuracy, precision, detection limit, quantitation limit, and ranges, next were tested and determined. The validated method than was used to analyze the levels of vitamin B1 and B6 simultaneously in the tablets. Vitamin B1 and B6 have the linear concentration range from 0.5 to 3.00% w/w. The regression equation for vitamin B1 is y = 0.0608 x-0.0176 with r = 0.9997 and Vx0 = 1.5047%, for vitamin B6: y = 0.0977 x+0.0079 r = 0.9995 and Vx0 = 1.7832%. Recovery results of vitamin B1: 98.98 to 100.93%, while B6: 99.06 to 100.43%. Intra-day and inter-day precision for vitamin B1: 1.73; 1.62; 1.48, and 0.58%, meanwhile for vitamin B6: 1.29; 1.60; 1.78, and 1.39%. The limits of detection and quantitation for vitamin B12 was 0.079 and 0.263% w/w respectively, and for vitamin B6, was: 0.093 and 0.311% w/w. The tablets from the market were tested showed the results that meet with compendia requirements. FTIR can be used for the determination of levels of vitamin B1 and B6 simultaneously in tablet dosage form and have met the validation requirements.
关键词： Pyridoxine hydrochloride,Thiamine hydrochloride,Derivative spectra,FTIR,Validation of method
更新于2025-09-10 09:29:36
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Validation of Himawari-8 aerosol optical depth retrievals over China
摘要： High temporal resolution (every 10 min) aerosol observations are rarely provided by satellite sensors. The Advanced Himawari Imager (AHI) aboard Himawari-8 can provide aerosol optical depth (AOD) over China with this frequency. The sensor provides great opportunity to retrieve the particle matter near the ground and improve air quality modeling using the aerosol products. However, there is still lack of quality validation about AHI AOD. A comprehensive research was conducted to evaluate the performance of AHI aerosol products based on sixteen sun-photometers stations in AErosol RObotic NETwork (AERONET) and Sun–Sky Radiometer Observation Network (SONET) over China. The overall comparison of AHI AOD and ground AOD shows a high correlation (R2=0.67). However, there is only 55% of AHI AOD falling in the expected error envelops (±0.05±0.2*AOD ground). AOD bias between AHI AOD and ground AOD increases with the AOD magnitude. The accuracy of AHI AOD is also highly depend on seasons and surface land cover types. Best performance of AHI aerosol retrievals is shown in summer and for urban region. The diurnal variability validation shows that AHI AOD catch the diurnal AOD variations well, especially for summer. Large differences between AHI AOD and MODerate-resolution Imaging Spectrometer (MODIS) aerosol products are shown, especially for northwest China. The analysis indicates that the uncertainties of AHI aerosol retrievals are induced by large errors of aerosol models and surface reflectance estimation in the algorithm.
关键词： MODIS,validation,Aerosol optical depth,Himawari-8
更新于2025-09-10 09:29:36
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Content evidence of a spectrographic analysis protocol
摘要： Objective: to verify the content evidence of a spectrographic analysis protocol. Methods: a methodological study in which five speech therapists who assessed the clarity and the relevance of the protocol were selected. The Content Validity Index (CVI) was used to investigate the level of agreement among judges regarding overall aspects, items and domains of the protocol. Results: most judges considered the overall aspects of the protocol as comprehensive. As for clarity, 17 items showed an excellent content validity (CVI ≥ 0.78), three showed a good content validity (0.60 ≤ CVI ≤ 0.77) and two items were judged as poor (CVI ≤ 0.59). As for relevance, 19 items obtained an excellent content validity (CVI ≥ 0.78) and three had a good content validity (0.60 ≤ CVI ≤ 0.77). The judges suggested adding items related to vocal signal normality in all domains. After the analysis, 18 items required no reformulation, five items were added, three were reformulated and one was excluded. Conclusion: the proposed protocol was regarded as a comprehensive one. The items presented a good to excellent content validity as for clarity and relevance. After this validation step, the protocol ended up presenting 25 items distributed into five domains.
关键词： Validation Studies,Voice Disorders,Voice,Sound Spectrography,Speech, Language and Hearing Sciences
更新于2025-09-10 09:29:36
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[IEEE 2018 IEEE International Conference on Vehicular Electronics and Safety (ICVES) - Madrid, Spain (2018.9.12-2018.9.14)] 2018 IEEE International Conference on Vehicular Electronics and Safety (ICVES) - Development of Robust Validation Method through Driverless Test for Vision-based Oncoming Vehicle Collision Avoidance System
摘要： This paper presents a robust validation test method to prove and improve the oncoming vehicle collision avoidance systems. This system is developed to reduce traffic accidents while a driver's vehicle crashes into an oncoming vehicle out of its lane. It consists of a front camera on the windshield to detect the vehicle on the other side and an electric power steering to control the host vehicle to prevent head-on collision. It requires high performance for planning and controlling accurate avoidance path at close distance at the right time. Thus, safe and accurate validation vehicle test method is essential to develop the high quality system and determine the performance. The proposed validation test method includes robust vehicle test scenarios with test specification, vehicle test equipment based on automated robots and detailed analysis method for system performance. The robust test scenarios with test specification are developed to prove robustness of the system and seek weakness points from diverse conditions on the road and test specifications. The vehicle robots based on GPS/INS are utilized to conduct validation tests safely, repeatedly and accurately as the designed the test scenarios. Overall, the suggested analysis method determines the reliability of robot tests by the error distribution of the dynamics and avoidance performance of the system through estimating internal errors of the components which cause errors of the avoidance system. The vehicles tests using presented robust test scenarios and driverless tests based on vehicle robots are conducted repeatedly to prove the robustness of the system thoroughly. The results of vehicle tests show the proposed method is powerful to validate the system and present proper value of design parameters applied to optimal avoidance path to improve the performance under the robust environment.
关键词： brake robot,analysis method,Oncoming vehicle collision avoidance system,steering robot,GPS/INS,validation method,acceleration robot
更新于2025-09-10 09:29:36
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Fast Microwave Through Wall Imaging Method With Inhomogeneous Background Based on Levenberg-Marquardt Algorithm
摘要： In this paper, a fast solution for microwave through wall imaging (TWI) with nonlinear inversion is proposed to reconstruct the unknown targets embedded in an inhomogeneous background medium. We treat inhomogeneous background, the wall around bounded in a finite domain as a known scatterer, which has the advantage of avoiding the time-consuming calculation of inhomogeneous background Green’s function. Under this scheme, a new approach under the framework of difference integral equation model, i.e., difference Lippmann–Schwinger integral equation, with modified enhanced Levenberg–Marquardt algorithm is proposed. In particular, we used a hybrid regularized technique, i.e., generalized cross-validation and truncated singular value decomposition, to stabilize the inversion. It is shown that the proposed method runs fast and is stable in presence of noise. Also, it is able to alleviate the nonlinearity and reconstruct unknown scatterers of high contrast with respect to the background. Both the numerical and experimental TWI tests validate the efficiency of the proposed inversion method.
关键词： microwave imaging,Generalized cross-validation (GCV) regularization,inhomogeneous background,inverse scattering problems (ISPs),Levenberg–Marquardt (LM) method
更新于2025-09-10 09:29:36
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Intercomparison of In-Situ and Remote Sensing Salinity Products in the Gulf of Mexico, a River-Influenced System
摘要： The recent emergence of satellite-based sea surface salinity (SSS) measurements provides new opportunities for oceanographic research on freshwater influence in coastal environments. Several products currently exist from multiple observing platforms and processing centers, making product selection for different uses challenging. Here we evaluate four popular SSS datasets in the Gulf of Mexico (GoM) to characterize the error in each product versus in-situ observations: Two products from NASA’s Soil Moisture Active Passive (SMAP) mission, processed by Remote Sensing Systems (REMSS) (40 km and 70 km); one SMAP 60 km product from the Jet Propulsion Laboratory (JPL); and one 60 km product from ESA’s Soil Moisture Ocean Salinity (SMOS) mission. Overall, the four products are remarkably consistent on seasonal time scales, reproducing dominant salinity features. Towards the coast, 3 of the 4 products (JPL SMAP, REMSS 40 km SMAP, and SMOS) show increasing salty biases (reaching 0.7–1 pss) and Root Mean Square Error (RMSD) (reaching 1.5–2.5 pss), and a decreasing signal to noise ratio from 3 to 1. REMSS 40 km generally shows a lower RMSD than other products (~0.5 vs. ~1.1 pss) in the nearshore region. However, at some buoy locations, SMOS shows the lowest RMSD values, but has a higher bias overall (>0.2 vs. <0.1 pss). The REMSS 70km product is not consistent in terms of data availability in the nearshore region and performs poorly within 100 km of the coast, relative to other products. Additional analysis of the temporal structure of the errors over a range of scales (8/9-day to seasonal) shows significantly decreasing RMSD with increasing timescales across products.
关键词： validation,SMOS,SMAP,sea surface salinity,Gulf of Mexico
更新于2025-09-10 09:29:36
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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 - Comparison of Different High-Resolution Soil Moisture Products Across an Agricultural Landscape in South-Eastern Australia
摘要： A number of satellite missions have the capability to provide surface soil moisture information at a range of spatial and temporal scales. However, the validation of such products heavily relies on point measurements from permanent stations, which may or may not be representative of the larger scale soil moisture conditions. Hence, methods need to be developed that allow the sampling of surface soil moisture on the ground across large scales over a reasonably short time scale, in order to capture the spatial variability within a footprint, or to provide spatially sufficiently large data sets to validate high-resolution products, be they at their native resolution or downscaled. In this study, two field-scale ground sampling techniques, namely stationary and roving Cosmic Ray Probes, are compared against a high-resolution satellite product. The data are compared for their temporal performance as well as with a focus on capturing the correct spatial variability. The challenge is the inherently different sensing depth of the various technologies. It is shown that this may largely be overcome through scaling the products.
关键词： Soil moisture,satellite product validation,cosmic ray probe
更新于2025-09-10 09:29:36
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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 - Evaluation of Smap Passive Soil Moisture Products Using In-Situ Data from a Dense Observation Network
摘要： As a result of vital role of soil moisture in governing water and energy cycles of land-atmosphere, the remote sensing of soil moisture has become a key component of the observation and research programs involving water and energy cycles on the earth's surface. In addition, the accurate monitoring and prediction of soil moisture plays a crucial role in crop growth, flood and drought monitoring and prediction, research of hydrological and land surface process and global water cycle. The microwave is the optimal mean to obtain soil moisture in large scale due to its strong penetration capability and sensitivity to the change of surface soil moisture. And the L band microwave is considered to be the best band for monitoring soil moisture. The Soil Moisture Active Passive (SMAP) satellite with an L-band (1.26 GHz) radar and an L-band radiometer (1.41 GHz) was launched on January 31, 2015 by the NASA. The baseline science requirement for SMAP is to provide estimates of soil moisture in the top 5 cm of soil with an error of no greater than 0.04 cm3/cm3 at 10 km spatial resolution and 3-day average intervals over the global land area. The soil moisture baseline algorithm of SMAP is single-channel algorithm using horizontally polarized TB (SCA-H). In SCA-H, the emissivity model of bare land uses a semi-empirical Hp model and the value of H is determined by using empirical method for different land cover types; The vegetation model with zero-order radiative transfer model to describe the influence of vegetation on the surface emissivity; The dielectric constant model is one of the three models of Mironov model, Dobson model and Wang model. The SMAP mission generates 22 different distributable data products. Here, we intended to evaluate the SMAP_L3_SM_P (the descending and ascending, 36km) and SMAP_L3_SM_P_E (the descending and ascending, 9km).Many domestic and foreign papers suggested that SMAP passive microwave soil moisture products close to or reach the accuracy requirement. A.Colliander et al. validated the SMAP L2 SM product with 34 core validation sites, and its accuracy reached the expected goal 0.04 cm3/cm3; Chan et al. found that the RMSE of SMAP L2 SM product is 0.038 cm3/cm3 in Little Washita, TxSON and Little River; Mehrjardi et al., Pan et al., J.Zeng et al. also suggested that SMAP soil moisture estimates were approaching the expected accuracy. Moreover, C. Ma et al. validated the SMAP L3 soil moisture products in the Heihe River Basin in China, and the ubRMSE is about 0.03 cm3/cm3. However, because of the regional characteristics of soil moisture retrieved by SMAP, it was necessary to evaluate the performance of SMAP SM product in different regions. At present, SMAP products had not been validated in large areas of farmland in China. In this study, a soil moisture observation network was designed and built in the farmland area of Dehui in Jilin Province, and the point-scale SM data were upscaled to provide the 36-km and 9-km SM to validate the SMAP_L3_SM_P and SMAP_L3_SM_P_E products. Although some papers pointed out that RFI in Northeast China is more serious, the farm areas chose were far from the RFI region. We measured the distance from the closest airfield to the experimental area greater than 40km and the amplitude of RFI was less than 2K, which meaned the impact of RFI on validation results could be ignored. The main content of this paper is as follows. The second part describes the study area, the construction of soil moisture observation network and data source. The third part illustrates the up-scaling methods and the evaluation indices of soil moisture products. The fourth part describes the validation results of SMAP passive microwave soil moisture products. Finally, the fifth part summarizes the main conclusions of this study.
关键词： validation,SMAP,soil moisture,upscaling,passive microwave
更新于2025-09-10 09:29:36
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Thermal modelling of a flat plate solar collector with latent heat storage validated with experimental data in outdoor conditions
摘要： This paper presents a thermal modelling strategy to evaluate the performance of latent heat storage technique in a ?at plate solar collector (FPSC) with integrated phase change material (PCM). A thermal dynamic model is developed based in simpli?ed semi empirical correlations and includes heat transfer by conduction, convection and radiation in each part of the device. Melting process of the PCM is described with energy balances for a set of discrete spatial layers to calculate temperature and liquid fraction. The model is validated with experimental data gathered under outdoor conditions from a real ?at plate solar collector prototype modi?ed to incorporate PCM containers between the absorber plate and the insulation. As result of the validation process, the model shows the capability to estimate the global thermal performance of the device with good accuracy compared with the experimental measurements and using minimal computational resources. Comparisons between estimations of the model and test data are presented for 20 days, real conditions include days with both high and low incident radiation and two di?erent PCMs. Predicted temperature of glass cover, absorber plate, water outlet and PCM are obtained with a maximum error of 4.62%. The model was employed to analyze the collector thermal performance. Temperatures, heat transfer, stored energy of collector main components and liquid fraction of PCM are estimated and analyzed in two cases: under clear sky condition without strong changes of solar radiation and under scattered weather with solar radiation variation. Two PCMs with di?erent melting points (45 °C and 60 °C) are analyzed and compared with results without PCM by using the model to evaluate their performance.
关键词： Flat plate solar collector,Thermal energy storage,Thermal model,Experimental validation,PCM
更新于2025-09-10 09:29:36