A Pole-Based Approach to Interpret Electromechanical Impedance Measurements in Structural Health Monitoring
Pith reviewed 2026-05-23 17:49 UTC · model grok-4.3
The pith
Vector fitting estimates stable poles from electromechanical impedance data to link measurements directly to damage-induced modal shifts.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Vector fitting is better suited for EMI-based structural health monitoring because it is more accurate at high frequency, estimates complex conjugate stable pole pairs close to the actual poles of the system, and can capture critical information missed by other approaches and present it in a condensed form, allowing shifts in natural frequencies to be attributed to changes in a structure undergoing damage.
What carries the argument
Vector fitting, a rational function approximation technique that estimates the poles of the underlying system from frequency-domain data.
If this is right
- Shifts in the estimated natural frequencies can be directly attributed to structural changes caused by damage.
- VF supplies a condensed representation that highlights the modal information most relevant to damage assessment.
- The approach yields physically intuitive post-processing of high-frequency EMI data compared with statistical metrics.
- Alternative rational fitting methods are shown to be less accurate or less stable for this monitoring task.
Where Pith is reading between the lines
- Combining VF pole estimates with finite-element models of candidate damage scenarios could enable more specific diagnosis of damage type and location.
- The method's emphasis on stable poles may support repeated measurements over time to separate damage effects from slow environmental drifts.
- Real-time implementation of VF on embedded sensors could turn raw EMI streams into automated alerts based on pole migration thresholds.
Load-bearing premise
Poles identified by vector fitting reliably match the physical modal parameters of the structure and their observed shifts can be attributed to damage rather than noise or environmental factors.
What would settle it
A controlled test on a structure with known damage where the VF-estimated pole shifts fail to match independently measured changes in natural frequencies, or where undamaged structures exhibit comparable pole shifts under varying temperature or noise conditions.
Figures
read the original abstract
Over several decades, electromechanical impedance (EMI) measurements have been employed as a basis for structural health monitoring and damage detection. Traditionally, Root-mean-squared-deviation (RMSD) and Cross-correlation (XCORR) based metrics have been used to interpret EMI measurements for damage assessment. These tools, although helpful and widely used, were not designed with the idea to assess changes in EMI to underlying physical changes incurred by damage. The authors propose leveraging vector fitting (VF), a rational function approximation technique, to estimate the poles of the underlying system, and consequently, the modal parameters which have a physical connection to the underlying model of a system. Shifts in natural frequencies, as an effect of changes in the pole location, can be attributed to changes in a structure undergoing damage. With VF, tracking changes between measurements of damaged and pristine structures is physically more intuitive unlike when using traditional metrics, making it ideal for informed post-processing. Alternative methods to VF exist in the literature (e.g., Least Square Complex Frequency-domain (LSCF) estimation, adaptive Antoulas--Anderson (AAA), Rational Krylov Fitting (RKFIT)). The authors demonstrate that VF is better suited for EMI-based structural health monitoring for the following reasons: 1. VF is more accurate at high frequency, 2. VF estimates complex conjugate stable pole pairs, close to the actual poles of the system, and 3. VF can capture critical information missed by other approaches and present it in a condensed form. Thus, using the selected technique for interpreting high-frequency EMI measurements for structural health monitoring is proposed. A set of representative case studies is presented to show the benefits of VF for damage detection and diagnosis.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper claims that vector fitting (VF) provides a physically interpretable alternative to traditional RMSD/XCORR metrics for analyzing electromechanical impedance (EMI) data in structural health monitoring. By approximating the admittance with a rational function, VF estimates stable complex-conjugate poles that are asserted to correspond to the system's modal parameters; shifts in these poles (hence natural frequencies) can then be directly attributed to damage. The authors argue VF outperforms LSCF, AAA, and RKFIT at high frequencies by producing more accurate, stable poles and condensing critical information, and they present case studies to illustrate the benefits for damage detection and diagnosis.
Significance. If the mapping from VF poles to uncoupled structural modes is established, the method would supply a more mechanistically grounded post-processing tool for high-frequency EMI-based SHM than purely statistical indices. The work applies an existing approximation technique to a practical monitoring problem and highlights its potential for intuitive tracking of physical changes.
major comments (3)
- [Abstract] Abstract and case-studies section: the claim that 'case studies demonstrate benefits' and that VF is 'better suited' rests on qualitative assertions without reported quantitative metrics, error bars, or explicit criteria for superiority (e.g., pole-error norms or damage-classification accuracy).
- [Background on EMI] Background and method sections: the central claim that VF poles are 'close to the actual poles of the system' and that their shifts can be attributed to structural damage requires an explicit sensitivity or inversion analysis relating the coupled electromechanical admittance (PZT-structure interaction) to the uncoupled structural natural frequencies; the manuscript provides no such mapping.
- [Comparison with Alternatives] Comparison with alternatives: the statements that VF is 'more accurate at high frequency' and 'captures critical information missed by other approaches' are not supported by tabulated pole-location errors, stability metrics, or cross-validation against known modal parameters in the presented experiments.
minor comments (2)
- [Introduction] Clarify the precise definition of 'actual poles of the system' (structural vs. coupled electromechanical) when first introduced.
- [Case Studies] Add a short table summarizing the number of poles retained, frequency range, and fitting residual for each method in the case studies.
Simulated Author's Rebuttal
We thank the referee for their constructive and detailed comments. We address each major comment point by point below, indicating planned revisions to strengthen the manuscript where the feedback identifies gaps in quantitative support or clarity.
read point-by-point responses
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Referee: [Abstract] Abstract and case-studies section: the claim that 'case studies demonstrate benefits' and that VF is 'better suited' rests on qualitative assertions without reported quantitative metrics, error bars, or explicit criteria for superiority (e.g., pole-error norms or damage-classification accuracy).
Authors: We agree that the abstract and case-study claims would benefit from quantitative backing. In the revised manuscript we will add explicit comparison criteria (e.g., magnitude and consistency of identified frequency shifts, pole-residue stability), include error norms for pole estimates against reference methods where feasible, and report variability from repeated measurements as error bars. These additions will make the superiority statements evidence-based rather than purely illustrative. revision: yes
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Referee: [Background on EMI] Background and method sections: the central claim that VF poles are 'close to the actual poles of the system' and that their shifts can be attributed to structural damage requires an explicit sensitivity or inversion analysis relating the coupled electromechanical admittance (PZT-structure interaction) to the uncoupled structural natural frequencies; the manuscript provides no such mapping.
Authors: The VF procedure is applied directly to the measured coupled admittance; the resulting poles therefore belong to the electromechanical system as observed. Damage-induced changes in the structure alter this coupled response, and the observed pole shifts serve as practical indicators. We will revise the background and method sections to state this distinction explicitly and to clarify that the method does not claim to recover uncoupled structural modes. A full analytical sensitivity mapping lies outside the scope of the present applied study. revision: partial
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Referee: [Comparison with Alternatives] Comparison with alternatives: the statements that VF is 'more accurate at high frequency' and 'captures critical information missed by other approaches' are not supported by tabulated pole-location errors, stability metrics, or cross-validation against known modal parameters in the presented experiments.
Authors: We will expand the comparison section with tabulated pole-location errors, stability indicators (e.g., condition numbers and residue norms), and any available cross-validation against reference modal data. These quantitative results will directly support the accuracy and information-capture claims at high frequencies. revision: yes
Circularity Check
No circularity: VF applied as external approximant to measured EMI data with independent comparison to alternatives
full rationale
The paper applies vector fitting (an established external rational approximation method) to measured electromechanical impedance data to extract poles, then compares accuracy and stability against independent alternatives (LSCF, AAA, RKFIT) on the same data. No equation or claim reduces the asserted superiority or the physical attribution of pole shifts to a parameter fitted from the target result itself, nor to a self-citation chain. The motivation that pole shifts track damage is presented as interpretive motivation rather than a derived theorem. The derivation chain therefore remains self-contained against external benchmarks and does not collapse by construction.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption Vector fitting produces poles that correspond to the modal parameters of the underlying electromechanical system
Reference graph
Works this paper leans on
-
[1]
General Electric. Fit to print: New plant will assemble world’s first passenger jet engine with 3D printed fuel nozzles, next-Gen Materials, jun 2014. URL https://www.ge.com/news/reports/fit-to-print
work page 2014
-
[2]
Sarah Goehrke. Rolls-Royce to Get Largest-Ever 3D Printed Component Off the Ground, Flight-Testing Engine Later This Year - 3DPrint.com | The V oice of 3D Printing / Additive Manufacturing, feb 2015. URL https: //3dprint.com/45820/rolls-royce-largest-3d-printed/
work page 2015
-
[3]
The Future of Exploration Starts With 3-D Printing, apr 2015
Brooke Boen. The Future of Exploration Starts With 3-D Printing, apr 2015. URL http://www.nasa.gov/ exploration/systems/sls/j2x/3d_print.html. Publisher: Brian Dunbar
work page 2015
-
[4]
Farrar, Graeme Manson, and Gyuhae Park
Keith Worden, Charles R. Farrar, Graeme Manson, and Gyuhae Park. The fundamental axioms of structural health monitoring. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 463(2082): 1639–1664, 2007. Publisher: The Royal Society London
work page 2082
-
[5]
Knowledge-based support in Non-Destructive Testing for health monitoring of aircraft structures
Bernard Kamsu-Foguem. Knowledge-based support in Non-Destructive Testing for health monitoring of aircraft structures. Advanced engineering informatics, 26(4):859–869, 2012. Publisher: Elsevier
work page 2012
-
[6]
Gyuhae Park, Hoon Sohn, Charles R Farrar, and Daniel J. Inman. Overview of Piezoelectric Impedance- Based Health Monitoring and Path Forward. The Shock and Vibration Digest , 35:451–463, may 2003. doi:10.1177/05831024030356001
-
[7]
Venu G. M. Annamdas and Madhav A. Radhika. Electromechanical impedance of piezoelectric transducers for monitoring metallic and non-metallic structures: A review of wired, wireless and energy-harvesting methods.Jour- nal of Intelligent Material Systems and Structures, 24(9):1021–1042, mar 2013. doi:10.1177/1045389x13481254. URL https://doi.org/10.1177/104...
-
[8]
Y . G. Xu and G. R. Liu. A Modified Electro-Mechanical Impedance Model of Piezoelectric Actuator-Sensors for Debonding Detection of Composite Patches. Journal of Intelligent Material Systems and Structures, 13(6):389– 396, jun 2002. doi:10.1177/104538902761696733. URL https://doi.org/10.1177/104538902761696733. Publisher: SAGE Publications
-
[9]
Stuart G. Taylor, Kevin Farinholt, Mijin Choi, Hyomi Jeong, Jaekyeong Jang, Gyuhae Park, Jung-Ryul Lee, and Michael D. Todd. Incipient crack detection in a composite wind turbine rotor blade. Journal of Intelligent Material Systems and Structures , 25(5):613–620, nov 2013. doi:10.1177/1045389x13510788. URL https: //doi.org/10.1177/1045389x13510788. Publis...
-
[10]
Corey Pitchford, Benjamin L. Grisso, and Daniel J. Inman. Impedance-based structural health monitoring of wind turbine blades. In Tribikram Kundu, editor, SPIE Proceedings, pages 508–518. SPIE, apr 2007. doi:10.1117/12.715800. URL https://doi.org/10.1117/12.715800
-
[11]
Piezoelectric Wafer Embedded Active Sensors for Aging Aircraft Structural Health Monitoring
Victor Giurgiutiu, Andrei Zagrai, and Jing Jing Bao. Piezoelectric Wafer Embedded Active Sensors for Aging Aircraft Structural Health Monitoring. Structural Health Monitoring , 1(1):41–61, jul 2002. doi:10.1177/147592170200100104. URL https://doi.org/10.1177/147592170200100104. Publisher: SAGE Publications
-
[12]
Venu Gopal Madhav Annamdas and Chee Kiong Soh. Application of electromechanical impedance technique for engineering structures: review and future issues. Journal of Intelligent material systems and structures, 21(1): 41–59, 2010. Publisher: Sage Publications Sage UK: London, England
work page 2010
-
[13]
Andrei Zagrai, Derek Doyle, Vlasi Gigineishvili, Jacob Brown, Hugh Gardenier, and Brandon Arritt. Piezoelectric Wafer Active Sensor Structural Health Monitoring of Space Structures.Journal of Intelligent Material Systems and Structures, 21(9):921–940, may 2010. doi:10.1177/1045389x10369850. URL https://doi.org/10.1177/ 1045389x10369850. Publisher: SAGE Pu...
-
[14]
Daniel M. Peairs, Pablo A. Tarazaga, and Daniel J. Inman. Frequency Range Selection for Impedance-Based Structural Health Monitoring. Journal of Vibration and Acoustics, 129(6):701–709, dec 2007. ISSN 1048-9002. doi:10.1115/1.2775506
-
[15]
Mohammad I. Albakri, Logan D. Sturm, Christopher B. Williams, and Pablo A. Tarazaga. Impedance-based non-destructive evaluation of additively manufactured parts. Rapid Prototyping Journal, 23(3):589–601, apr 2017. ISSN 1355-2546. doi:10.1108/RPJ-03-2016-0046. URL https://www.emerald.com/insight/content/ doi/10.1108/RPJ-03-2016-0046/full/html . Publisher: Emerald
-
[16]
Logan D. Sturm, Mohammed I. Albakri, Pablo A. Tarazaga, and Christopher B. Williams. In situ monitoring of material jetting additive manufacturing process via impedance based measurements. Additive Manufacturing, 28:456–463, aug 2019. ISSN 22148604. doi:10.1016/j.addma.2019.05.022. URL https://linkinghub. elsevier.com/retrieve/pii/S2214860419300909. Publi...
-
[17]
George Sapidis, Maria Naoum, Nikos Papadopoulos, and Maristella V outetaki. Flexural Damage Evaluation in Fiber Reinforced Concrete Beams Using a PZT-Based Health Monitoring System. In Agnieszka J˛ edrzejewska, Fragkoulis Kanavaris, Miguel Azenha, Farid Benboudjema, and Dirk Schlicke, editors, International RILEM Conference on Synergising Expertise toward...
-
[18]
Maria C. Naoum, Constantin E. Chalioris, Chris G. Karayannis, Athanasios I. Karabinis, and Anaxago- ras Elenas. Electro-Mechanical Impedance-Based Structural Health Monitoring of Fiber-Reinforced Con- crete Specimens under Four-Point Repeated Loading. CivilEng, 4(3):856–880, sep 2023. ISSN 2673-4109. doi:10.3390/civileng4030047. URL https://www.mdpi.com/2...
-
[19]
Albakri, Joseph Kubalak, Logan D
Charles Tenney, Mohammad I. Albakri, Joseph Kubalak, Logan D. Sturm, Christopher B. Williams, and Pablo A. Tarazaga. Internal porosity detection in additively manufactured parts via electromechanical impedance measure- ments. In Smart Materials, Adaptive Structures and Intelligent Systems, volume 58257, page V001T08A009, 2017
work page 2017
-
[20]
Prathamesh N. Bilgunde and Leonard J. Bond. In-situ health monitoring of piezoelectric sensors using electrome- chanical impedance: A numerical perspective. AIP Conference Proceedings, 1949(1):230011, apr 2018. ISSN 0094-243X. doi:10.1063/1.5031658. URL https://doi.org/10.1063/1.5031658
-
[21]
Structural Health Monitoring Method for In Situ Inspection of Landing Gears
Gökhan Haydarlar, Mesut Tekkalmaz, and Mehmet Alper Sofuo˘glu. Structural Health Monitoring Method for In Situ Inspection of Landing Gears. In Melih Cemal Ku¸ shan, Selim Gürgen, and Mehmet Alper Sofuo ˘glu, editors, Materials, Structures and Manufacturing for Aircraft, pages 211–238. Springer International Publishing, Cham, 2022. ISBN 978-3-030-91873-6. ...
-
[22]
C. Liang, F. P. Sun, and C. A. Rogers. Coupled Electro-Mechanical Analysis of Adaptive Material Systems — Determination of the Actuator Power Consumption and System Energy Transfer. Journal of Intelligent Material Systems and Structures, 5(1):12–20, jan 1994. ISSN 1045-389X. doi:10.1177/1045389X9400500102
-
[23]
Victor Giurgiutiu and Andrei N. Zagrai. Characterization of Piezoelectric Wafer Active Sensors. Journal of Intelligent Material Systems and Structures, 11(12):959–976, dec 2000. doi:10.1106/a1hu-23jd-m5au-engw. URL https://doi.org/10.1106/a1hu-23jd-m5au-engw . Publisher: SAGE Publications
- [24]
-
[25]
Fan Ping Sun, Z. Chaudhry, C. Liang, and C. A. Rogers. Truss structure integrity identification using PZT sensor- actuator. Journal of Intelligent material systems and structures, 6(1):134–139, 1995. Publisher: TECHNOMIC PUBLISHING CO., INC. 851 New Holland Ave., Box 3535, Lancaster, PA
work page 1995
-
[26]
Three-Dimensional Electromechanical Impedance Model
Venu Gopal Madhav Annamdas and Chee Kiong Soh. Three-Dimensional Electromechanical Impedance Model. I: Formulation of Directional Sum Impedance. Journal of Aerospace Engineering, 20(1):53–62, jan 2007. ISSN 0893-1321. doi:10.1061/(ASCE)0893-1321(2007)20:1(53). URL https://ascelibrary.org/doi/10.1061/ %28ASCE%290893-1321%282007%2920%3A1%2853%29. Publisher:...
-
[27]
Three-Dimensional Electromechanical Impedance Model
Venu Gopal Madhav Annamdas and Chee Kiong Soh. Three-Dimensional Electromechanical Impedance Model. II: Damage Analysis and PZT Characterization. Journal of Aerospace Engineering, 20(1):63–71, jan 2007. ISSN 0893-1321. doi:10.1061/(ASCE)0893-1321(2007)20:1(63). URL https://ascelibrary.org/doi/10.1061/ %28ASCE%290893-1321%282007%2920%3A1%2863%29. Publisher...
-
[28]
Vibrational Based Inspection of Civil Engineering Structures
Anders Rytter. Vibrational Based Inspection of Civil Engineering Structures . PhD thesis, Dept. of Building Technology and Structural Engineering, Aalborg University, 1993. Backup Publisher: Aalborg University Issue: 44
work page 1993
-
[29]
K. K.-H. Tseng and A. S. K. Naidu. Non-parametric damage detection and characterization using smart piezo- ceramic material. Smart Materials and Structures, 11(3):317, may 2002. ISSN 0964-1726. doi:10.1088/0964- 1726/11/3/301. URL https://dx.doi.org/10.1088/0964-1726/11/3/301
-
[30]
Olivier Cherrier, Pierre Selva, Valérie Pommier-Budinger, Frédéric Lachaud, and Joseph Morlier. Damage localization map using electromechanical impedance spectrums and inverse distance weighting interpolation: Experimental validation on thin composite structures. Structural Health Monitoring , 12(4):311–324, 2013. doi:10.1177/1475921713493343. URL https:/...
-
[31]
Damage location method for thin composites structures-application to an aircraft door
Valérie Pommier-Budinger, Olivier Cherrier, Joseph Morlier, and Frederic Lachaud. Damage location method for thin composites structures-application to an aircraft door. In AST 2013 4th International Workshop on Aircraft System Technologies, page 0, 2013
work page 2013
-
[32]
Effect of Temperature and Thermal Cycles on PZT Ceramic Performance in Fuel Injector Applications
Sadegh Davoudi. Effect of Temperature and Thermal Cycles on PZT Ceramic Performance in Fuel Injector Applications. Thesis, University of Toronto, November 2012. URL https://tspace.library.utoronto.ca/ handle/1807/33393. Accepted: 2012-11-21T20:21:09Z
work page 2012
-
[33]
Thanh-Canh Huynh and Jeong-Tae Kim. Quantification of temperature effect on impedance monitoring via PZT interface for prestressed tendon anchorage. Smart Materials and Structures, 26(12):125004, October 2017. ISSN 0964-1726. doi:10.1088/1361-665X/aa931b. URL https://dx.doi.org/10.1088/1361-665X/aa931b. Publisher: IOP Publishing
-
[34]
L. O’Gorman and A. Sanderson. The converging squares algorithm: An efficient multidimensional peak picking method. In ICASSP ’83. IEEE International Conference on Acoustics, Speech, and Signal Processing , vol- ume 8, pages 112–115, apr 1983. doi:10.1109/ICASSP.1983.1172227. URL https://ieeexplore.ieee.org/ document/1172227/?arnumber=1172227
-
[35]
S. W. Doebling, C. R. Farrar, M. B. Prime, and D. W. Shevitz. Damage identification and health monitoring of structural and mechanical systems from changes in their vibration characteristics: A literature review. Technical Report LA-13070-MS, Los Alamos National Lab. (LANL), Los Alamos, NM (United States), may 1996. URL https://www.osti.gov/biblio/249299
work page 1996
-
[36]
R. J. Allemang and D. L. Brown. A UNIFIED MATRIX POLYNOMIAL APPROACH TO MODAL IDENTIFICA- TION. Journal of Sound and Vibration, 211(3):301–322, apr 1998. ISSN 0022-460X. doi:10.1006/JSVI.1997.1321. Publisher: Academic Press
-
[37]
Mohammad I. Albakri and Pablo A. Tarazaga. Dynamic analysis of a piezoelectric augmented beam system with adhesive bonding layer effects. Journal of Intelligent Material Systems and Structures, 28(2):178–194, 2017. Publisher: SAGE Publications Sage UK: London, England
work page 2017
-
[38]
B. Gustavsen and A. Semlyen. Rational approximation of frequency domain responses by vector fitting. IEEE Transactions on Power Delivery, 14(3):1052–1061, 1999. doi:10.1109/61.772353
-
[39]
B. Gustavsen. Improving the pole relocating properties of vector fitting. IEEE Transactions on Power Delivery, 21(3):1587–1592, 2006. doi:10.1109/TPWRD.2005.860281
-
[40]
Macromodeling of Multiport Systems Using a Fast Implementation of the Vector Fitting Method
Dirk Deschrijver, Michal Mrozowski, Tom Dhaene, and Daniel De Zutter. Macromodeling of Multiport Systems Using a Fast Implementation of the Vector Fitting Method. IEEE Microwave and Wireless Components Letters, 18(6):383–385, 2008. doi:10.1109/LMWC.2008.922585
-
[41]
H. Van der Auweraer and B. Peeters. Discriminating physical poles from mathematical poles in high order systems: use and automation of the stabilization diagram. In Proceedings of the 21st IEEE Instrumentation and Measurement Technology Conference (IEEE Cat. No.04CH37510), volume 3, pages 2193–2198 V ol.3, may
-
[42]
URL https://ieeexplore.ieee.org/document/1351525
doi:10.1109/IMTC.2004.1351525. URL https://ieeexplore.ieee.org/document/1351525. ISSN: 1091-5281
-
[43]
Van der Auweraer, P. Guillaume, and S. Vanlanduit. Application of a fast-stabilizing frequency domain parameter estimation method. Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME, 123(4): 651–658, 2001. ISSN 15289028. doi:10.1115/1.1410369
-
[44]
The RKFIT Algorithm for Nonlinear Rational Approximation
Mario Berljafa and Stefan Güttel. The RKFIT Algorithm for Nonlinear Rational Approximation. SIAM Journal on Scientific Computing, 39(5):A2049–A2071, 2017. doi:10.1137/15M1025426
-
[45]
Yuji Nakatsukasa, Olivier Sète, and Lloyd N. Trefethen. The AAA Algorithm for Rational Approximation. SIAM Journal on Scientific Computing, 40(3):A1494–A1522, 2018. doi:10.1137/16M1106122. 29 A Pole-Based Approach to Interpret EMI in SHM A PREPRINT
-
[46]
Wave propagation in structures: an FFT-based spectral analysis methodology
James F Doyle. Wave propagation in structures: an FFT-based spectral analysis methodology. Springer Science & Business Media, 2012
work page 2012
-
[47]
Monitoring damage propagation using pzt impedance transducers
Yaowen Yang, Hui Liu, Venu Gopal Madhav Annamdas, and Chee Kiong Soh. Monitoring damage propagation using pzt impedance transducers. Smart Materials and Structures, 18(4):045003, March 2009. ISSN 0964-1726. doi:10.1088/0964-1726/18/4/045003
-
[48]
Quantification of damage sensitivity by electromechanical impedance signatures
SK Singh and PH Malinowski. Quantification of damage sensitivity by electromechanical impedance signatures. In Proc. 7th Asia Pacific Workshop on Structural Health Monitoring, 2018. 30 A Pole-Based Approach to Interpret EMI in SHM A PREPRINT Appendix Table 3: Analytical, LSCF estimated and VF estimated for 5 DoF system (Undamaged) Undamaged Analytical LSC...
work page 2018
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