- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 28th Wireless and Optical Communications Conference (WOCC) - Beijing, China (2019.5.9-2019.5.10)] 2019 28th Wireless and Optical Communications Conference (WOCC) - An Improved Kalman Filter for TOA Localization using Maximum Correntropy Criterion
摘要： Kalman ?lter (KF) has been widely used in data ?ltering and smoothing applications. However, it is generally limited by the requirement of white-Gaussian noise. In practical applications, such as indoor localization, TOA distance ranging results are mostly affected by multipath and non-line-of-sight (NLOS) factors, which introduces colored Gaussian noise into the system. In this study, we intend to take advantage of maximum correntropy criterion to enhance the ranging performance. We proposed a Constrained Kalman Filter based on the Maximum Correntropy Criterion (MCC-CKF) to realize high-accuracy TOA ranging in the extreme environments of multipath and NLOS.
关键词： non-line-of-sight(NLOS),indoor positioning,constrained Kalman ?lter,Time of Arrival (TOA),maximum entropy criterion(MCC)
更新于2025-09-11 14:15:04
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Image-Based Visibility Estimation Algorithm for Intelligent Transportation Systems
摘要： Posted road speed limits contribute to the safety of driving, yet when certain driving conditions occur, such as fog or severe darkness, they become less meaningful to the drivers. To overcome this limitation, there is a need for adaptive speed limits system to improve road safety under varying driving conditions. In that vein, a visibility range estimation algorithm for real-time adaptive speed limits control in intelligent transportation systems is proposed in this paper. The information required to specify the speed limit is captured via a road side unit that collects environmental data and captures road images, which are then analyzed locally or on the cloud. The proposed analysis is performed using two image processing algorithms, namely, the improved dark channel prior (DCP) and weighted image entropy (WIE), and the support vector machine (SVM) classi?er is used to produce a visibility indicator in real-time. Results obtained from the analysis of various parts of highways in Canada, provided by the Ministry of Transportation of Ontario (MTO), show that the proposed technique can generate credible visibility indicators to motorists. The analytical results corroborated by extensive ?eld measurements con?rmed the advantage of the proposed system when compared to other visibility estimation methods such as the conventional DCP and WIE, where the proposed system results exhibit about 25% accuracy enhancement over the other considered techniques. Moreover, the proposed DCP is about 26% faster than the conventional DCP. The obtained promising results potentiate the integration of the proposed technique in real-life scenarios.
关键词： image processing,dark channel prior,intelligent transportation system,SVM,Visibility,smart cities,entropy,machine learning
更新于2025-09-11 14:15:04
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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 - Research Into Sar Imaging of Moving Ship Target Based on Isar Technology
摘要： The ship targets affected by sea conditions and other environment factors have complex non-cooperation movement, which cause serious defocusing phenomena in high resolution space-borne SAR images. In this paper, a novel ISAR-based imaging algorithm for moving ship target is presented. Firstly, the spatial geometric model of space-borne SAR is given, and the motorial characteristics of moving ship target are analyzed. Then, a novel imaging algorithm is derived, where the range alignment is solved by minimum information entropy criterion, and the accurate focusing is achieved through inverse SAR (ISAR) processing. Experiments based on the simulation and real data of TerraSAR-X are performed to validate the presented algorithm.
关键词： Motion compensation,Inverse Synthetic Aperture Radar(ISAR),Radar imaging,Minimum entropy,Moving Ship Target
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 - Simulation of Isar Motion Compensation for Moving Targets Based on Particle Swarm Optimization
摘要： In inverse synthetic aperture radar (ISAR) imaging, the imaging results can be affected by the unexpected target motions. This results in a blurry and unrecognizable image. The motion parameters estimation is a compensation method to improve the ISAR image refocusing and quality. In this study, the backscattered echo signals are simulated by the linear geometry system of ISAR moving targets. The entropy of ISAR image is used as a criterion to evaluate the image quality. Furthermore, this entropy measure can be treated as a cost function of the particle swarm optimization (PSO) method and minimized by PSO to improve the quality of ISAR images. The experimental results showed that our proposed PSO motion estimation approach to entropy minimization for ISAR imaging can not only efficiently improve the estimation capability of motion parameters, but also significantly achieve a better performance of ISAR image refocusing.
关键词： motion compensation,entropy minimization,particle swarm optimization (PSO),inverse synthetic aperture radar
更新于2025-09-10 09:29:36
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Measuring and Monitoring Urban Sprawl of Jaipur City using Remote Sensing and GIS
摘要： The world’s population increased drastically and forced people to migrate from rural area to major cities in search of basic amenities. The majority of the World’s population are already living in the major cities and it is continuously increasing. The increase in population forced the major cities to expand. Expansion of cities acclaimed more unplanned settlement that leads unplanned growth. This is a global phenomenon that has a direct impact on natural resources. It is the biggest challenge for urban planners to achieve sustainable development. Developing countries like India, where the population is increasing at an alarming pace, require more attention towards this problem. In this study, an attempt has been made to measure and monitor urban sprawl in Jaipur (Capital, State of Rajasthan, India). Built-up area with corresponding population has been analysed over a period of 41 years (1972-2013). Remotely sensed images of 1972-2013 (MSS, TM and ETM+) have been classified using Supervised Maximum Likelihood Classification (MLC) for digital image processing. Shannon’s entropy has been used to quantify the degree of urban sprawl, and eight landscape metrics have also been used to quantify urban sprawl and its pattern.
关键词： Remote Sensing,GIS,Shannon’s Entropy,Urban Sprawl,Landscape Metrics
更新于2025-09-10 09:29:36
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The inverse perovskite BaLiF <sub/>3</sub> : single-crystal neutron diffraction and analyses of potential ion pathways
摘要： Doped barium lithium tri?uoride has attracted attention as component for scintillators, luminescent materials and electrodes. With lithium and ?uoride, it contains two possibly mobile species, which may account for its ionic conductivity. In this study, neutron diffraction on oxide-containing BaLiF3 single-crystals is performed at up to 636.2(cid:2)C. Unfortunately, ion-migration pathways could not be mapped by modelling anharmonic ion displacement or by inspecting the scattering-length density that was reconstructed via maximum-entropy methods. However, analyses of the topology and bond-valence site energies derived from the high-temperature structure reveal that the anions can migrate roughly along the edges of the LiF6 coordination octahedra with an estimated migration barrier of (cid:3)0.64 eV (if a vacancy permits), whereas the lithium ions are con?ned to their crystallographic positions. This ?nding is not only valid for the title compound but for ion migration in all perovskites with Goldschmidt tolerance factors near unity.
关键词： bond-valence energy landscape,topological analysis,high-temperature neutron diffraction,maximum-entropy methods,fluoroperovskite
更新于2025-09-10 09:29:36
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Understanding the Role of Ferroelastic Domains on the Pyroelectric and Electrocaloric Effects in Ferroelectric Thin Films
摘要： Temperature- and electric-field-induced structural transitions in a polydomain ferroelectric can have profound effects on its electrothermal susceptibilities. Here, the role of such ferroelastic domains on the pyroelectric and electrocaloric response is experimentally investigated in thin films of the tetragonal ferroelectric PbZr0.2Ti0.8O3. By utilizing epitaxial strain, a rich set of ferroelastic polydomain states spanning a broad thermodynamic phase space are stabilized. Using temperature-dependent scanning-probe microscopy, X-ray diffraction, and high-frequency phase-sensitive pyroelectric measurements, the propensity of domains to reconfigure under a temperature perturbation is quantitatively studied. In turn, the “extrinsic” contributions to pyroelectricity exclusively due to changes between the ferroelastic domain population is elucidated as a function of epitaxial strain. Further, using highly sensitive thin-film resistive thermometry, direct electrocaloric temperature changes are measured on these polydomain thin films for the first time. The results demonstrate that temperature- and electric-field-driven domain interconversion under compressive strain diminish both the pyroelectric and the electrocaloric effects, while both these susceptibilities are enhanced due to the exact-opposite effect from the extrinsic contributions under tensile strain.
关键词： electrocaloric effect,ferroelastic domains,ferroelectricity,pyroelectric effect,entropy
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Smart Meter Working Status Evaluation Method Based on Evidence Theory
摘要： This paper presents a method to evaluate smart meter working status by analyzing multi-data of smart meters. It is a multi-source data fusion technique based on D-S evidence theory. In the proposed algorithm, entropy method used to compute the weight of indicators, then we use convex function to assign the probabilities of evidence. Finally, we obtain the evaluation working status by D-S evidence theory. The results of simulation indicate the applicability of the approach in real time scenarios.
关键词： smart meter working status,Multi-data Fusion,D-S evidence theory,convex function,entropy method
更新于2025-09-10 09:29:36
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[IEEE 2018 IEEE International Conference on System, Computation, Automation and Networking (ICSCAN) - Pondicherry, India (2018.7.6-2018.7.7)] 2018 IEEE International Conference on System, Computation, Automation and Networking (ICSCA) - Robust RGB Image Thresholding with Shannon’s Entropy and Jaya Algorithm
摘要： Image thresholding is a common pre-processing procedure implemented in various domains to improve the picture quality. In this work, thresholding of benchmark RGB- scale picture is implemented with the Jaya Algorithm (JA) and Shannon’s Entropy (SE). The investigational work is executed using Matlab7 software on RGB pictures of varied sizes. This work examines the original and the noise stained pictures based on the chosen threshold. In order to assess the performance of JA+SE, Picture-Quality-Measures (PQM) are computed by comparing the original and thresholded pictures. The average outcome confirms that, JA+SE provide better PQM values in both the normal and noise corrupted cases. Hence, this study confirms that, pre-processing with SE helps to attain better values of the error and PSNR values for the considered images of different size and quality.
关键词： Shannon’s Entropy,Gaussian-Noise,Examination.,Thresholding,RGB image
更新于2025-09-10 09:29:36
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Contextual Information Based Quality Assessment for Contrast-Changed Images
摘要： In this paper, we propose the objective metric which can precisely predict the perceptual quality of contrast-changed images using inter-pixel contextual information. The metric consists of two parts. One is a 2D histogram-based contrast quality measure which utilizes the distribution of the gray-level differences between adjacent pixels. We design the desired 2D histogram considering the characteristic of an adequately high contrast image, and predict contrast quality by comparing the desired 2D histogram with 2D histograms of an original image and a contrast-changed image. The other is a spatial entropy based one which uses the information of spatial location distribution of gray-levels. A comparison is carried out with many IQA metrics on five contrast related databases. Experimental results show that the proposed metric provides a more accurate prediction of human perception of contrast change than other metrics.
关键词： 2D histogram and spatial entropy,Image quality assessment (IQA),contrast-changed images
更新于2025-09-10 09:29:36