An Interferometric W-BAND Radar for Large Structures Monitoring

Interferometric radars are widely used for static and dynamic monitoring of large structures such as bridges, culverts, wind turbine towers, chimneys, masonry towers, stay cables, buildings, and monuments. Most of these radars operate in Ku-band (17 GHz). Nevertheless, a higher operative frequency could allow the design of smaller, lighter, and faster equipment. In this paper, a fast MIMO-GBSAR (Multiple-Input Multiple-Output Ground-Based Synthetic Aperture Radar) operating in W-band (77 GHz) has been proposed. The radar can complete a scan in less than 8 s. Furthermore, as its overall dimension is smaller than 230 mm, it can be easily fixed to the head of a camera tripod, which makes its deployment in the field very easy, even by a single operator. The performance of this radar was tested in a controlled environment and in a realistic case study.

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Electrical Resistance Tomography Based Sensing Skin with Internal Electrodes for Crack Detection in Large Structures: Preliminary Results Standard Difference Imaging Study

ASNT 27th Annual Research Sumposium Proceedings ◽

10.32548/rs.2018.013 ◽

2018 ◽

Cited By ~ 1

Author(s):

Reza Rashetnia ◽

◽

Omar Khalaf Alla ◽

Guillermo Gonzalez-Berrios3 ◽

Aku Seppänen ◽

...

Keyword(s):

Electrical Resistance ◽

Crack Detection ◽

Imaging Study ◽

Electrical Resistance Tomography ◽

Preliminary Results ◽

Large Structures ◽

Sensing Skin ◽

Standard Difference ◽

Difference Imaging

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Proteins and direct methods

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1991.197.3-4.197 ◽

1991 ◽

Vol 197 (3-4) ◽

Cited By ~ 7

Author(s):

Fan Hai-fu ◽

Hao Quan ◽

M. M. Woolfson

Keyword(s):

First Principles ◽

Figure Of Merit ◽

Direct Methods ◽

Large Structure ◽

Low Resolution ◽

Figures Of Merit ◽

Large Structures ◽

Resolution Data

AbstractConventional direct methods, which work so well for small structures, are less successful for macromolecules. Where it has been demonstrated that a solution might be found using direct methods it is then found that the usual figures of merit are unable to distinguish the few good sets of phases from the large number of sets generated. The reasons for the difficulties with very large structures are considered from a first-principles approach taking into account both the factors of having a large number of atoms and low resolution data. A proposal is made for trying to recognize good phase sets by taking a large structure as a sum of a number of smaller structures for each of which a conventional figure of merit can be applied.

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