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基于时间序列SAR影像分析方法的三峡大坝稳定性监测

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中国科学：地球科学 2011年第1期41卷 110-123页

作者：王腾 daniele perissin Fabio ROCCA 廖明生武汉大学测绘遥感信息工程国家重点实验室武汉430079 Politecnico di Milano Dipartimento di Elettronica e InformazioneMilan 20133Italy 香港中文大学太空与地球信息科学研究所中国香港

本文提出了结合永久散射体和准永久散射体干涉测量技术的时间序列合成孔径雷达(SAR)影像几何信息提取方案,利用2003～2008年获取的40景SAR影像量测并分析了三峡大坝运行时的稳定性问题及其周边区域的形变规律.我们发现在数据获取期间,... 详细信息

本文提出了结合永久散射体和准永久散射体干涉测量技术的时间序列合成孔径雷达(SAR)影像几何信息提取方案,利用2003～2008年获取的40景SAR影像量测并分析了三峡大坝运行时的稳定性问题及其周边区域的形变规律.我们发现在数据获取期间,三峡大坝左段的时效沉降基本停止,大坝形变受水位的影响较大,季节性变化也有一定体现.该实验结果和已发表的该坝段形变监测结果十分吻合.在数据处理结果中我们还在大坝上游秭归县附近堤坝发现一处形变异常.研究结果表明了时间序列SAR影像信息提取技术在大坝稳定性监测及坝区形变参数获取中的应用潜力.

关键词：三峡工程形变监测合成孔径雷达干涉测量永久散射体技术

Long-Term Land Deformation Monitoring Using Quasi-Persistent Scatterer (Q-PS) Technique Observed by Sentinel-1A: Case Study Kelok Sembilan

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Advances in Remote Sensing 2018年第4期7卷 277-289页

作者： Pakhrur Razi Josaphat Tetuko Sri Sumantyo daniele perissin Hiroaki Kuze Physics Department Universitas Negeri Padang Sumatra Indonesia Center for Environmental Remote Sensing Chiba University Chiba Japan Lyle School of Civil Engineering Purdue University West Lafayette IN USA

Located on the mountainous area, Kelok Sembilan flyover area in West Sumatra, Indonesia has a long history of land deformation, therefore monitoring and analyzing as continuously is a necessity to minimize the impact. Notably, in the rainy season, the land deformation occurs along this area. The zone is crucial as the center of transportation connection in the middle of Sumatra. Quasi-Persistent Scatterer (Q-PS) Interferometry technique was applied for extracting information of land deformation on the field from time to time. Not only does the method have high performance for detecting land deformation but also improve the number of PS point, especially in a non-urban area. This research supported by 90 scenes of Sentinel-1A (C-band) taken from October 2014 to November 2017 for ascending and descending orbit with VV and VH polarization in 5 × 20 m (range × azimuth) resolution. Both satellite orbits detected two critical locations of land deformation namely as zone A and Zone B, which located in positive steep slope where there is more than 500 mm movement in the Line of Sight (LOS) during acquisition time. Deformations in the vertical and horizontal direction for both zone, are 778.9 mm, 795.7 mm and 730.5 mm, 751.7 mm, respectively. Finally, the results were confirmed by ground truth data using Unmanned Aerial Vehicle (UAV) observation.

关键词： Interferometry Synthetic Aperture Radar Land Deformation Q-PS Technique Kelok Sembilan

On the Proper Homotopy Invariance of the Tucker Property

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Acta Mathematica Sinica,English Series 2007年第3期23卷 571-576页

作者： daniele Ettore OTERA Universitádi Palermo Dipartimento di Matematica ed Applicazionivia Archirafi 3490123-PalermoItaly and Université Paris-SudMathématiquesBt 42591405 Orsay Cedex-France

A non-compact polyhedron P is Tucker if, for any compact subset K begong to P, the fundamental group π1 （P - K） is finitely generated. The main result of this note is that a manifold which is proper homotopy equivalent to a Tucker polyhedron is Tucker. We use Poenaru＇s theory of the equivalence relations forced by the singularities of a non-degenerate simplicial map.

关键词： proper homotopy Φ/ψ-theory tucker property

A recursive implementation of the ALIENOR optimization method

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International Journal of Intelligent Computing and Cybernetics 2021年第2期14卷 81-103页

作者： daniele Peri National Research Council(CNR) Istituto per le Applicazioni del Calcolo“Mauro Picone”–IACRomaItaly

Purpose-A recursive scheme for the ALIENOR method is proposed as a remedy for the difficulties induced by the method.A progressive focusing on the most promising region,in combination with a variation of the density of the alpha-dense curve,is ***/methodology/approach-ALIENOR method is aimed at reducing the space dimensions of an optimization problem by spanning it by using a single alpha-dense curve:the curvilinear abscissa along the curve becomes the only design parameter for any design *** a counterpart,the transformation of the objective function in the projected space is much more difficult to ***-A fine tuning of the procedure has been performed in order to identity the correct balance between the different elements of the *** proposed approach has been tested by using a set of algebraic functions with up to 1,024 design variables,demonstrating the ability of the method in solving large scale optimization *** an industrial application is ***/value-In the knowledge of the author there is not a similar paper in the current literature.

关键词： ALIENOR optimization Global optimization Lipschitzian optimization Reduced order base

Evolution of turbulent boundary layer over a three-dimensional bump

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Chinese Journal of Aeronautics 2022年第6期35卷 137-145页

作者： Jun LIU daniele FISCALETTI Huacheng YUAN College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Civil Aerospace and Mechanical EngineeringUniversity of BristolBristol BS81TRUK

A bump is typically used in the inlet system of an aircraft engine to compress the incoming airflow and to reduce boundary layer thickness developed over *** this work,the turbulent flow over a three-dimensional bump is experimentally *** bump model is mounted in a closed return wind tunnel operated at the nominal velocity 10 m/s,corresponding to a friction Reynolds number of *** flow field upstream the bump,along the bump centerline and at two different spanwise planes is measured with Particle Image Velocimetry(PIV).It is observed that a favorable pressure gradient develops until the suction peak of the bump,and that the average turbulence intensity within boundary layer is attenuated due to this favorable pressure *** boundary layer thickness identified by examining profiles of streamwise velocity decreases significantly along the *** wall-normal position of the Turbulent/Non-Turbulent Interface(TNTI)identified with the vorticity criterion is also observed to decrease along the *** studying the behavior of the boundary layer thickness at different spanwise positions,we found that it tends to be larger in planes away from the centreline,which suggests that the bump diverts the flow.

关键词： Bump Divertless inlet Particle Image Velocimetry(PIV) Turbulent boundary layer Turbulent/Non-Turbulent Interface(TNTI)

Single-point and Filtered Relative Position Estimation for Visual Docking

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Computer Modeling in Engineering & Sciences 2016年第2期111卷 147-169页

作者： Dylan Conway daniele Mortari Aerospace Engineering Texas A&M UniversityCollege Station77843

This paper presents a new method to estimate position from line-ofsight measurements to known targets when attitude is *** algorithm has two *** first produces a closed-form unbiased estimate for position that does not account for the measurement error *** second stage is iterative and produces an estimate of position that explicitly accounts for the measurement error covariance and the coupling between measurement error and sensor-to-target *** algorithm gives an accurate estimate of both position and the corresponding position error covariance and has a low computational *** computational complexity is O(n)for n point-targets and only a 3×3 linear system must be *** algorithm is demonstrated for single-point position estimation to verify the accuracy of the resulting position and *** improvements over current methods are shown through statistical *** algorithm is then demonstrated in the context of sequential filtering for space vehicle docking.

关键词： Visual point algorithm

King's College criteria and the Clichy-Villejuif criteria require adjustments for assessing acute liver failure due to yellow fever

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World Journal of Transplantation 2025年第1期15卷 124-134页

作者： Bruno da Silva Athanasio Antonio Marcio de Faria Andrade Vivian Vasconcelos Costa Juliano Felix Castro Silverio Leonardo Macedo Garcia Mauro Martins Teixeira daniele da Gloria Souza Paula Vieira Teixeira Vidigal Cristiano Xavier Lima Department of Surgery Federal University of Minas GeraisBelo Horizonte 30130-100Minas GeraisBrazil Liver Transplantation Unit Felicio Rocho HospitalBelo Horizonte 30110-934Minas GeraisBrazil Department of Morphology Federal University of Minas GeraisBelo Horizonte 31270-901Minas GeraisBrazil Department of Biochemistry and Immunology Federal University of Minas GeraisBelo Horizonte 31270-901Minas GeraisBrazil Department of Pathology Federal University of Minas GeraisBelo Horizonte 30130-100Minas GeraisBrazil

BACKGROUND Acute liver failure(ALF)is a severe condition characterized by rapid deterioration of liver function in individuals without preexisting liver *** transplantation(LT)is the most impactful *** fever(YF)is an infectious disease that primarily affects the liver and has a high mortality ***,LT can be a viable option for treating rare cases with extensive liver ***,the criteria for assessing the severity of ALF and determining the indications for transplantation have not been specifically validated for cases caused by *** To present necessary adjustments to established scoring systems for ALF secondary to *** This was an observational,retrospective,single-center *** consecutive patients with confirmed ALF due to YF were monitored in the intensive care unit by a specialized liver transplant team during a three-month epidemic outbreak in *** hospitalization,general supportive therapeutic measures were implemented,and the patients were regularly assessed using the King's College criteria and the Clichy-Villejuif criteria to determine the severity of liver *** is considered a viable measure for patients with signs of end-stage liver *** Eight of 14(57%)patients developed severe neurological alterations within the first 96 hours after hospital *** patients underwent emergency LT,and despite a moderate viral infection of the graft after transplantation,the 5-year survival rate was 50%.Although the King's College criteria and the Clichy-Villejuif criteria are the main scoring systems for ALF,they are insufficient for predicting the risk of mortality in this context,primarily because of low serum bilirubin levels in the final stage of the disease and significant disparities between coagulation abnormalities and patient *** To ensure good applicability in cases of YF-induced ALF,the authors suggest adaptations to the King's College and Clichy-Vill

关键词： Yellow fever Acute liver failure Liver transplantation King's College criteria Clichy-Villejuif criteria

Influence of Process Parameters and Sr Addition on the Microstructure and Casting Defects of LPDC A356 Alloy for Engine Blocks

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Journal of Materials Science & Technology 2016年第6期32卷 515-523页

作者： Giulio Timelli daniele Caliari Jovid Rakhmonov Department of Management and Engineering University of PadovaStradeUa S.Nicola3 1-36100 VicenzaItaly

The effects of Sr addition and pressure increase on the microstructure and casting defects of a low-pressure die cast （LPDC） AISi7Mg0.3 alloy have been studied. Metallographic and image analysis techniques have been used to quantitatively examine the microstructural changes and the amount of porosity occurring at different Sr levels and pressure parameters. The results indicate that an increase in the filling pressure induces lower heat dissipation of the liquid close to the die/core surfaces, with the formation of slightly greater dendrite arms and coarser eutectic Si particles. On the other hand, the increase in the Sr level leads to finer microstructural scale and eutectic Si. The analysed variables, within the experimental conditions, do not affect the morphology of eutectic Si particles. Higher applied pressure and Sr content generate castings with lower amount of porosiW. However, as the filling pressure increases the flow of metal inside the die cavity is more turbulent, leading to the formation of oxide films and cold shots. In the analysed range of experimental conditions, the design of experiment methodology and the analysis of variance have been used to develop statistical models that accurately predict the average size of secondary dendrite arm spacing and the amount of porosity in the low-pressure die cast AISiTMg0.3 alloy.

关键词： Aluminium alloys Engine block Microstructure Casting defects Sr addition Process parameters

On “Over-Sized” High-Gain Practical Observers for Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2018年第3期5卷 691-698页

作者： daniele Carnevale Corrado Possieri Antonio Tornambè Dipartimento di Ingegneria Civile e Ingegneria Informatica Universita di Roma Tor Vergata

In this paper,it is shown that the performances of a class of high-gain practical observers can be improved by estimating the time derivatives of the output up to an order that is greater than the dimension of the system, which is assumed to be in observability form and, possibly, time-varying. Such an improvement is achieved without increasing the gain of the observers, thus allowing their use in a wide variety of control and identification applications.

关键词： Filtering properties nonlinear systems observability observer design