The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform

Carmelo Gentile - One of the best experts on this subject based on the ideXlab platform.

  • Vibration-based structural health monitoring of stay cables by Microwave Remote Sensing
    Smart Structures and Systems, 2015
    Co-Authors: Carmelo Gentile, Alessandro Cabboi
    Abstract:

    Copyright © 2015 Techno-Press, Ltd. Microwave Remote Sensing is probably the most recent experimental technique suitable to the non-contact measurement of deflections on large structures, in static or dynamic conditions. In the first part of the paper, the main techniques adopted in Microwave Remote Sensing are described, so that advantages and potential issues of these techniques are presented and discussed. Subsequently, the paper addresses the application of the radar technology to the measurement of the vibration response on the stay cables of two cable-stayed bridges. The dynamic tests were performed in operational conditions (i.e. with the excitation being mainly provided by micro-tremors, wind and traffic) and the maximum deflections of the cables were generally lower than 5.0 mm. The investigation clearly highlights: (a) the safe and simple use of the radar on site and its effectiveness to simultaneously measure the dynamic response of all the stay cables of an array; (b) the negligible effects of the typical issues and uncertainties that might affect the radar measurements; (c) the accuracy of the results provided by the Microwave Remote Sensing in terms of natural frequencies and tension forces of the stay cables; (d) the suitability of Microwave interferometry to the repeated application within Structural Health Monitoring programmes.

  • Vibration measurement on large structures by Microwave Remote Sensing
    2012
    Co-Authors: Carmelo Gentile
    Abstract:

    Recent advances in radar techniques and systems have led to the development of Microwave interferometers, suitable for the non-contact vibration monitoring of large structures. In the first part of the paper, the main techniques adopted in Microwave Remote Sensing are described, so that advantages and potential issues of these techniques are addressed and discussed. Subsequently, the results of past and recent tests of full-scale structures are presented, in order to demonstrate the reliability and accuracy of Microwave Remote Sensing; furthermore, the simplicity of use of the radar technology is exemplified in practical cases, where the access with conventional techniques is uneasy or even hazardous, such as the stay cables of cable-stayed bridges.

  • Microwave Remote Sensing of Vibrating Stay Cables
    2010
    Co-Authors: Carmelo Gentile
    Abstract:

    The paper addresses the application of Microwave Remote Sensing to the measurement of the vibration response in the stay‐cables of cable‐stayed bridges. The investigation, carried out on the cables of two different cable‐stayed bridges, clearly highlights: (a) the accuracy of the results provided by the Microwave Remote Sensing; (b) the simplicity of use of the radar technique (especially when compared with conventional approaches) and its effectiveness to simultaneously measuring the dynamic response of all the stay‐cables of an array; (c) the repeatability of the test with Structural Health Monitoring purposes.

  • Application of Microwave Remote Sensing to Dynamic Testing of Stay-Cables
    Remote Sensing, 2009
    Co-Authors: Carmelo Gentile
    Abstract:

    Recent advances in radar techniques and systems have favoured the development of Microwave interferometers, suitable for the non-contact vibration monitoring of large structures. The paper addresses the application of Microwave Remote Sensing to the measurement of the vibration response in the stay-cables of cable-stayed bridges. The reliability and accuracy of the proposed technique were investigated by comparing the natural frequencies (and the cable tensions predicted from natural frequencies) identified from radar data and the corresponding quantities obtained using more conventional techniques. The investigation, carried out on the cables of two different cable-stayed bridges, clearly highlights: (a) the accuracy of the results provided by the Microwave Remote Sensing; (b) the simplicity of use of the radar technique (especially when compared with conventional approaches) and its effectiveness to simultaneously measuring the dynamic response of all the stay-cables of an array.

Thomas J. Jackson - One of the best experts on this subject based on the ideXlab platform.

  • Introduction to the special issue on large scale passive Microwave Remote Sensing of soil moisture
    IEEE Transactions on Geoscience and Remote Sensing, 2001
    Co-Authors: Thomas J. Jackson, V. Lakshmi
    Abstract:

    ASSIVE Microwave Remote Sensing of soil moisture has been a focus of research for several decades. Only in recent years has this work begun to address the key issues related to implementing this approach as part of large scale and global applications such as climate analysis and prediction. The papers collected in this Special Issue on Large Scale Passive Microwave Remote Sensing of Soil Moisture address one of three important aspects that will eventually contribute to operational studies. These are • theoretical and experimental investigations to develop and refine robust retrieval algorithms; • demonstration of retrieval techniques over regional scales using aircraft and satellite observations; • integration of Remotely sensed soil moisture measurements in hydrologic applications. One additional paper is included that describes a planned L-band satellite mission. The impending launches of the ad

  • Multifrequency ground-based Microwave Remote Sensing of soil moisture
    IGARSS '98. Sensing and Managing the Environment. 1998 IEEE International Geoscience and Remote Sensing. Symposium Proceedings. (Cat. No.98CH36174), 1998
    Co-Authors: Charles A. Laymon, William L. Crosson, V.v. Soman, Thomas J. Jackson, A. Manu, Teferi D. Tsegaye
    Abstract:

    A multifrequency passive Microwave Remote Sensing system was deployed during a ground-based experiment. Conducted near Huntsville, Alabama in 1996. The Sand L-band Microwave radiometers were able to detect both the large scale moisture changes due to the irrigation and rainfall events and also diurnal fluctuations in surface soil moisture content. Using a two frequency system provides much more information about near-surface soil water dynamics than does a single frequency.

  • iii measuring surface soil moisture using passive Microwave Remote Sensing
    Hydrological Processes, 1993
    Co-Authors: Thomas J. Jackson
    Abstract:

    Soil moisture is one of the few directly observable hydrological variables that has an important role in water and energy budgets necessary for climate studies. At the present time there is no practical approach to measuring and monitoring soil moisture at the frequency and scale necessary for these large scale analyses. Current and developing satellite systems have not addressed this important question. A solution utilizing passive Microwave Remote Sensing is presented here and an optimum system, soil moisture estimation algorithms and a Microwave simulation model are described.

Noah P. Molotch - One of the best experts on this subject based on the ideXlab platform.

  • Microwave Remote Sensing for Land Hydrology Research and Applications: Introduction to the Special Issue
    IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2010
    Co-Authors: Eni G. Njoku, Mahta Moghaddam, Delwyn Moller, Noah P. Molotch
    Abstract:

    This special issue focuses on recent advances in Microwave Remote Sensing for hydrologic research and applications. Papers in this special issue cover topics addressed at the International Workshop on Microwave Remote Sensing for Land Hydrology Research and Applications held in Oxnard, CA, on October 20-22, 2008. Current research in understanding and predicting phenomena related to the global water cycle has emphasized the need for: (1) better observations and characterizations of land surface parameters that govern water and energy exchanges between the surface and atmosphere, and (2) long-term measurements of these parameters over a range of spatial and temporal scales. Recent advances in active and passive Microwave Sensing have indicated the potential of spaceborne Microwave sensors for measuring hydrologic variables of soil, vegetation, snow, and surface water. Using improved data assimilation techniques, it is now possible to integrate Remotely sensed and in situ observations from multiple sources in a physically consistent framework for comprehensive assessments of the water status of the land hydrosphere and biosphere.

V. Lakshmi - One of the best experts on this subject based on the ideXlab platform.

  • Introduction to the special issue on large scale passive Microwave Remote Sensing of soil moisture
    IEEE Transactions on Geoscience and Remote Sensing, 2001
    Co-Authors: Thomas J. Jackson, V. Lakshmi
    Abstract:

    ASSIVE Microwave Remote Sensing of soil moisture has been a focus of research for several decades. Only in recent years has this work begun to address the key issues related to implementing this approach as part of large scale and global applications such as climate analysis and prediction. The papers collected in this Special Issue on Large Scale Passive Microwave Remote Sensing of Soil Moisture address one of three important aspects that will eventually contribute to operational studies. These are • theoretical and experimental investigations to develop and refine robust retrieval algorithms; • demonstration of retrieval techniques over regional scales using aircraft and satellite observations; • integration of Remotely sensed soil moisture measurements in hydrologic applications. One additional paper is included that describes a planned L-band satellite mission. The impending launches of the ad

Eni G. Njoku - One of the best experts on this subject based on the ideXlab platform.

  • Microwave Remote Sensing for Land Hydrology Research and Applications: Introduction to the Special Issue
    IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2010
    Co-Authors: Eni G. Njoku, Mahta Moghaddam, Delwyn Moller, Noah P. Molotch
    Abstract:

    This special issue focuses on recent advances in Microwave Remote Sensing for hydrologic research and applications. Papers in this special issue cover topics addressed at the International Workshop on Microwave Remote Sensing for Land Hydrology Research and Applications held in Oxnard, CA, on October 20-22, 2008. Current research in understanding and predicting phenomena related to the global water cycle has emphasized the need for: (1) better observations and characterizations of land surface parameters that govern water and energy exchanges between the surface and atmosphere, and (2) long-term measurements of these parameters over a range of spatial and temporal scales. Recent advances in active and passive Microwave Sensing have indicated the potential of spaceborne Microwave sensors for measuring hydrologic variables of soil, vegetation, snow, and surface water. Using improved data assimilation techniques, it is now possible to integrate Remotely sensed and in situ observations from multiple sources in a physically consistent framework for comprehensive assessments of the water status of the land hydrosphere and biosphere.