- 标题
- 摘要
- 关键词
- 实验方案
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Preservation of image edge feature based on snowfall model smoothing filter
摘要： This paper proposed a snowfall model as a novel smoothing filter. The pixel composition of the image was similar to the geographic features, so it could be smooth because of snow accumulation. In the snowfall processing, luminance changes are linked to terrain and snowfall amount. Curvature and luminance gradient decided the amount of snowfall; the amount of snowfall became large on the parts where the curvature was large, and it became little on the parts where the gradient was steep. Snowfall algorithm simulates the natural snowfall process, which nonlinear diffusion and the target feature could be preserved well. Snowfall model has the same function as the Gaussian filter. The number of regions was reduced after Gaussian filter and snowfall model smoothing, respectively. The contrast experiment was carried out based on Watershed algorithm. The image area segmentation that pretreated through snowfall model was compared with Gaussian filter smoothing. The experimental result showed that the proposed snowfall model was a smoothing filter. It was able to realize edge preservation, which was the original purpose, and it was also possible to apply to region segmentation.
关键词： Snowfall model,Smoothing filter,Region segmentation,Edge characteristics,Image preservation
更新于2025-09-23 15:23:52
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Diode Array Near Infrared Spectrometer Calibrations for Composition Analysis of Single Plant Canola (Brassica napus) Seed
摘要： A canola breeder needs an accurate, rapid, non-destructive method for analyzing seeds from a single plant to select the most promising samples for further breeding trials. Near Infrared Spectroscopy (NIRS) is widely used for quantitative analysis of oilseeds in a non-destructive manner. This research was aimed at developing NIRS calibration models for single plant canola seed using a diode array NIRS (950-1650 nm wavelength range), multivariate prediction models, and a mirrored sample cup. Eighteen different NIRS calibration models were developed using 100 samples for each constituent with different pre-processing techniques (mean center, derivatives, variates) and models (PLS, PCR). The relative performance of different calibration models for each constituent was compared using R2, SEP, and ratio performance deviation (RPD) values obtained from the validation set of 30 samples. NIRS models developed using the PLS regression algorithm for moisture content (R2 = 0.97, SEP = 0.32, RPD = 6.13) and oil content (R2 = 0.84, SEP = 0.61, RPD = 4.16) were successful. However, acceptable NIRS models were not obtained for fatty acid and glucosinolates content likely due to limited variability and low levels of the constituent and a narrow wavelength range of the DA-NIR instrument.
关键词： Moisture content,Diode array,Fatty acid composition,Mirrored cup,DA-NIRS,Oil content,Oleic acid,Stearic acid,NIRS calibration model,Palmitic acid
更新于2025-09-23 15:23:52
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[IEEE 2017 14th IEEE India Council International Conference (INDICON) - Roorkee (2017.12.15-2017.12.17)] 2017 14th IEEE India Council International Conference (INDICON) - Impact of intermittent wind and solar resources on the dynamics of power system under different loading conditions
摘要： This paper presents the impact of renewable energy systems i.e. wind and solar on the load frequency control aspects of power system. An interconnected two area power system is modeled with backlash in the governor and generation rate constraint (GRC) in the turbine dynamics. The system is integrated with wind and solar resources in the form of a time series data with a resolution of one fifth of a second. The impact of these two renewable energy resources on the frequency response of power system is analyzed in terms of maximum overshoot (MP) and settling time (ts).
关键词： frequency deviation,peak overshoot,renewables integration,settling time,two area model.
更新于2025-09-23 15:23:52
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Application of blurred circular 3D images on the human vision model
摘要： By letting students simulate operations and games on a digital education operation system, schools are able to inspect learning achievement and teaching quality. In digital education area, we are able to use blockchain technology to simplify process, improve competition mode. It’s helpful improve efficiency and avoid the problem of opaque and falsification messages. Besides, it can provide unchangeable digital certification of academic achievement. Based on existing research foundation, against features on related users and services, especially the standard and trustful problem in competitions and evaluation mode nowadays, I studied competition mode based on blockchain technology, designed blockchain’s application mode and frame, analyzed evaluation criteria and algorithm, designed an operational skill evaluation model, developed an operational skill competition evaluation system based on e-business sandbox and experimented it.
关键词： digital education,evaluation model,blockchain,operational skill competition,fuzzy AHP,balanced score card
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE 10th Sensor Array and Multichannel Signal Processing Workshop (SAM) - Sheffield (2018.7.8-2018.7.11)] 2018 IEEE 10th Sensor Array and Multichannel Signal Processing Workshop (SAM) - Subspace-Based Imaging Using Only Power Measurements
摘要： In this paper, we are interested in the high-resolution imaging of an unknown area based on only power measurements of a small number of wireless transceivers located on one side of the unknown area. In order to do so, we propose a framework that achieves a polynomial order reduction in the number of antennas required for high-resolution imaging. More specifically, we show that by spacing the antennas at multiples of the wavelength and applying subspace-based analysis, we can image M targets using only 2M +1 transmit/receive antennas (as compared to the state-of-the-art value of M 2 + 1 antennas). We then validate our framework using simulations in both noise-free and noisy environments.
关键词： Super-resolution imaging,Time Reversal MUSIC,Rytov Model
更新于2025-09-23 15:23:52
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Simulated and observed horizontal inhomogeneities of optical thickness of Arctic stratus
摘要： Two-dimensional (2D) horizontal fields of cloud optical thickness derived from airborne measurements of solar spectral radiance during the Vertical Distribution of Ice in Arctic Clouds (VERDI) campaign (carried out in Inuvik, Canada in April/May 2012) are compared with semi-idealized Large Eddy Simulations (LES) of Arctic stratus performed with the COnsortium for Small-Scale MOdeling (COSMO) atmospheric model. The input for the LES is obtained from collocated airborne dropsonde observations. Four consecutive days of a persistent Arctic stratus observed above the sea-ice free Beaufort Sea are selected for the comparison. Macrophysical cloud properties such as cloud top altitude and vertical extent are well captured by COSMO. Cloud horizontal inhomogeneity quantified by the standard deviation and one-dimensional (1D) inhomogeneity parameters show that COSMO produces only half of the measured horizontal cloud inhomogeneities, while the directional structure of the cloud inhomogeneity is well represented by the model. Differences between the individual cases are mainly associated with the wind shear near cloud top and the vertical structure of the atmospheric boundary layer. A sensitivity study changing the wind velocity in COSMO by a vertically constant scaling factor shows that the directional cloud inhomogeneity structures strongly depend on the mean wind speed. A threshold wind velocity is identified, which determines when the cloud inhomogeneity stops increasing with increasing wind velocity.
关键词： airborne measurements,COSMO model,horizontal inhomogeneity,wind speed sensitivity,Large Eddy Simulation,Arctic stratus,cloud optical thickness
更新于2025-09-23 15:23:52
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Characterization of the solar climate in Malawi using NASAs surface meteorology and solar energy (SSE) model
摘要： This paper presents the characterization of global solar radiation (GSR) for Malawi using NASA’s SSE model. The mean monthly daily GSR monthly variation in the three regions of Malawi has been investigated. It has been found that there is a general gradient in GSR in the north-south direction. This gradient correlates well with the variation of the clearness index in the same direction (r = 0.986). It has been observed that the GSR is characteristic of each region. Simple analytic polynomials have been proposed for estimating solar radiation in the traditional Northern, Central and Southern regions of Malawi. There is a strong agreement between the polynomials and the SSE model with R2 values of 0.988, 0.989 and 0.989 and root mean square errors of 0.061, 0.057 and 0.062 kWh/m2.day for the regions, respectively.
关键词： surface meteorology and solar energy (SSE) model,global solar radiation,Malawi,solar climate
更新于2025-09-23 15:23:52
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Analysis of nonlinear large signal intrinsic elements for InGaP/GaAs HBT based on Gummel-Poon model
摘要： A large signal analysis method based on Gummel‐Poon model is proposed to predict nonlinear behavior of InGaP/GaAs HBT. A 2 × 20 μm2 transistor is fabricated with InGaP/GaAs HBT technology. The large signal transconductance Gm, conductance Gbe, and capacitance CBE, CBC are calculated based on the proposed method and measured using a RF testing probe. The calculated and measured results show good consistency up to nonlinear power level. The proposed method is applied to analyze variations of nonlinear large signal intrinsic elements of this transistor with increasing power under different bias conditions, in order to raise benefit of nonlinear consideration for power amplifiers.
关键词： Gummel‐Poon,nonlinear,large signal model,GaAs HBT
更新于2025-09-23 15:23:52
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New automated method for extracting river information using optimized spectral threshold water index
摘要： The accurate extraction of mountain river information is highly significant in water resource investigation and ecological environment protection. However, there are some problems in the existing methods of river information extraction, which are mainly the interference from shadows and buildings. Such interference leads to erroneous and redundant extraction of river information, which leads to inaccuracy or incompleteness. In this study, a precise extraction method of mountain river information is established using Landsat8 image and digital elevation model. The main steps of the river extraction method are as follows: (1) we propose the optimized spectral threshold water index to extract river information; (2) based on digital elevation model data, we simulate the mountain shadows of the study area to remove interference from them; (3) we establish the buffer zone of the river network using digital elevation model data to solve the problem of redundant extraction of river information; (4) we separately calculate and then standardize land surface temperature, albedo, and normalized different building index. The effects of buildings near the river are removed. Results show a relative accuracy of 97.52%. The new method decreases the interference of mountain shadows and buildings.
关键词： Digital elevation model,Mountain shadow,Building removal,River buffer zone,Landsat8
更新于2025-09-23 15:23:52
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Advancing the PROSPECT-5 Model to Simulate the Spectral Reflectance of Copper-Stressed Leaves
摘要： This paper proposes a modified model based on the PROSPECT-5 model to simulate the spectral reflectance of copper-stressed leaves. Compared with PROSPECT-5, the modified model adds the copper content of leaves as one of input variables, and the specific absorption coefficient related to copper (Kcu) was estimated and fixed in the modified model. The specific absorption coefficients of other biochemical components (chlorophyll, carotenoid, water, dry matter) were the same as those in PROSPECT-5. Firstly, based on PROSPECT-5, we estimated the leaf structure parameters (N), using biochemical contents (chlorophyll, carotenoid, water, and dry matter) and the spectra of all the copper-stressed leaves (samples). Secondly, the specific absorption coefficient related to copper (Kcu) was estimated by fitting the simulated spectra to the measured spectra using 22 samples. Thirdly, other samples were used to verify the effectiveness of the modified model. The spectra with the new model are closer to the measured spectra when compared to that with PROSPECT-5. Moreover, for all the datasets used for validation and calibration, the root mean square errors (RMSEs) from the new model are less than that from PROSPECT-5. The differences between simulated reflectance and measured reflectance at key wavelengths with the new model are nearer to zero than those with the PROSPECT-5 model. This study demonstrated that the modified model could get more accurate spectral reflectance from copper-stressed leaves when compared with PROSPECT-5, and would provide theoretical support for monitoring the vegetation stressed by copper using remote sensing.
关键词： vegetation remote sensing,leaf,PROSPECT,reflectance model,copper,spectra
更新于2025-09-23 15:23:52