Relevant bibliographies by topics / Model updating method

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Model updating method'

Author: Grafiati
Published: 3 June 2025
Last updated: 13 July 2025

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Journal articles on the topic "Model updating method"

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Yin, Hong, Jingjing Ma, Kangli Dong, Zhenrui Peng, Pan Cui, and Chenghao Yang. "Model Updating Method Based on Kriging Model for Structural Dynamics." Shock and Vibration 2019 (April 23, 2019): 1–12. http://dx.doi.org/10.1155/2019/8086024.

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Model updating in structural dynamics has attracted much attention in recent decades. And high computational cost is frequently encountered during model updating. Surrogate model has attracted considerable attention for saving computational cost in finite element model updating (FEMU). In this study, a model updating method using frequency response function (FRF) based on Kriging model is proposed. The optimal excitation point is selected by using modal participation criterion. Initial sample points are chosen via design of experiment (DOE), and Kriging model is built using the corresponding acceleration frequency response functions. Then, Kriging model is improved via new sample points using mean square error (MSE) criterion and is used to replace the finite element model to participate in optimization. Cuckoo algorithm is used to obtain the updating parameters, where the objective function with the minimum frequency response deviation is constructed. And the proposed method is applied to a plane truss model FEMU, and the results are compared with those by the second-order response surface model (RSM) and the radial basis function model (RBF). The analysis results showed that the proposed method has good accuracy and high computational efficiency; errors of updating parameters are less than 0.2%; damage identification is with high precision. After updating, the curves of real and imaginary parts of acceleration FRF are in good agreement with the real ones.
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Rui, Qiang, and Hong Yan Wang. "SRSM-Based Stochastic Model Updating Method." Advanced Materials Research 774-776 (September 2013): 12–16. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.12.

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With the combination of stochastic response surface model (SRSM) and Monte Carlo simulation (MCS)-based inverse error propagation method, a computational efficiency stochastic model updating approach has been proposed. The SRSM of original finite element model is determined using the Hermite polynomial chaos expansion and regression-based efficient collocation method. The efficiency of this method is demonstrated as a large number of computational demanding full model simulations are no longer essential, and instead, the updating of parameter mean values and variances is implemented on explicit SRSM. The effectiveness of this approach is validated through a bolt-jointed double-hat structure numerical example. The proposed method can be applied on stochastic uncertainty quantification of complex engineering structures.
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Hu, Sau-Lon James, Huajun Li, and Shuqing Wang. "Cross-model cross-mode method for model updating." Mechanical Systems and Signal Processing 21, no. 4 (2007): 1690–703. http://dx.doi.org/10.1016/j.ymssp.2006.07.012.

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Nobari, Ali Salehzadeh, and Mohammad Ali Farjoo. "Comparison Between Dedicated Model Updating Methods and Hybrid Method." Journal of Aircraft 41, no. 5 (2004): 999–1004. http://dx.doi.org/10.2514/1.260.

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Krasnorutskiy, D. A., P. A. Lakiza, V. A. Berns, and E. P. Zhukov. "Finite Element Model Updating Method of Dynamic Systems." PNRPU Mechanics Bulletin, no. 3 (December 15, 2021): 84–95. http://dx.doi.org/10.15593/perm.mech/2021.3.08.

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The finite element model updating method of dynamical systems based on results of modal tests is proposed. The purpose of updating is to change eigenspectrum. The method alters a stiffness matrix by adding an updating finite element model created on the nodes of the intial one with respect to the existing links between the linear degrees of freedom. The stiffnesses of the updating elements are utilized as the updating parameters to be defined. The objective function equals to the least square weighted sum of residuals between the target, which were determined experimentally, and current values of modal stiffnesses. The iterative solution process is carried out. At each iteration step the conjugate gradient method is applied to solve the unconstrained minimization problem. The modeshapes, which were calculated as the result of solving the generalized eigenvalue problem at the previous iteration step, are employed to calculate the current modal stiffnesses. The method does not have a limit to a size of matrices and keeps their sparsity and symmetry. It provides the model updating of selected regions of a structure and step-by-step model updating of predefined groups of eigenfrequencies. Moreover, geometrical features of a structure, such as the presence of the symmetry planes and structurally identical elements, may be taken into account. The method is implemented into a program and verified by the example of the free dynamically-scaled model of Tu-204. In order to perform the ground vibration testing, the model was suspended with a low-rigidity flexible support. The finite element model made of solid elements has been updated on the basis of the six experimentally determined sets of eigenfrequencies. The target frequencies from each set have been achieved with a high level of accuracy.
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Sanko, Nobuhiro. "Updating function model: Model updating method transferable in a wider range of data sizes." Asian Transport Studies 8 (2022): 100071. http://dx.doi.org/10.1016/j.eastsj.2022.100071.

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Yang, J., H. F. Lam, and J. Hu. "Ambient Vibration Test, Modal Identification and Structural Model Updating Following Bayesian Framework." International Journal of Structural Stability and Dynamics 15, no. 07 (2015): 1540024. http://dx.doi.org/10.1142/s0219455415400246.

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Structural health monitoring (SHM) of civil engineering structures based on vibration data includes three main components: ambient vibration test, modal identification and model updating. This paper discussed these three components in detail and proposes a general framework of SHM for practical application. First, a fast Bayesian modal identification method based on Fast Fourier Transform (FFT) is introduced for efficiently extracting modal parameters together with the corresponding uncertainties from ambient vibration data. A recently developed Bayesian model updating method using Markov chain Monte Carlo simulation (MCMCS) is then discussed. To illustrate the performance of the proposed modal identification and model updating methods, a scale-down transmission tower is investigated. Ambient vibration test is conducted on the target structure to obtain modal parameters. By using the measured modal parameters, model updating is carried out. The MCMC-based Bayesian model updating method can efficiently evaluate the posterior marginal PDFs of the uncertain parameters without calculating high-dimension numerical integration, which provides posterior uncertainties for the target systems.
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Li, Zhi Gang, Ying Chao Li, Shu Qing Wang, and Bin Yang. "Finite Element Model Updating of a Steel Jacket Scale Model." Applied Mechanics and Materials 166-169 (May 2012): 588–92. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.588.

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In this paper, the finite element model of a steel jacket scale model is updated using modal parameters identified by modal test. Updating parameters are selected based on sensitivity analysis by solving modal energies. And then, a two-steps updating process is carried out using different parameters and the Cross-Model Cross-Mode (CMCM) model updating method is applied in each step. Results indicate that with selection of updating parameters and sensitivity analysis, CMCM method can update the finite element model with physical meanings.
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Wei, Chunjie, and Jian Wang. "The Modified Increment Method for Eigenspace Model." Academic Journal of Applied Mathematical Sciences, no. 74 (August 13, 2021): 187–91. http://dx.doi.org/10.32861/ajams.74.187.191.

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Eigenspace is a convenient way to represent sets of observations with widespread applications, so it is necessary to accurately calculate the eigenspace of data. With the advent of the era of big data, the increasing and updating of data bring great challenges to the solution of eigenspace. Hall, et al. [1], proposed that the incremental method could update the eigenspace of data online, which reduces computational costs and storage space. In this paper, the updating coefficient of the sample covariance matrix in an incremental method is modified. Numerical analysis shows that the modified updating form has better performance.
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Zhang, De-Wen, and Lingmi Zhang. "Matrix transformation method for updating dynamic model." AIAA Journal 30, no. 5 (1992): 1440–43. http://dx.doi.org/10.2514/3.11083.

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Dissertations / Theses on the topic "Model updating method"

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Hanson, David Mechanical &amp Manufacturing Engineering Faculty of Engineering UNSW. "Operational modal analysis and model updating with a cyclostationary input." Awarded by:University of New South Wales. School of Mechanical and Manufacturing Engineering, 2006. http://handle.unsw.edu.au/1959.4/31199.

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This thesis addresses the problem of identifying the modal properties of a system based only on measurements of the system responses. This situation is frequently encountered in structural dynamics and is particularly relevant for systems where the in-service excitation is not artificially reproducible. The inherent non-linearities in these systems mean that the modal properties estimated using traditional input/output techniques will be different to those exhibited in operation. A common example from the literature is an aircraft in flight where the modal properties are heavily influenced by the operating point, i.e. the combination of load, speed, altitude etc., at which the aircraft is travelling. The process of identifying the modal properties of systems in-service is called Operational Modal Analysis (OMA). Not knowing the input complicates the analysis. Most of the techniques in the literature overcome the lack of knowledge about the unmeasured excitations by assuming they are both spatially and frequentially white, i.e. of equal magnitude and with a flat autospectrum. This thesis presents a new technique for OMA which relaxes these constraints, requiring only that the system is excited by a so called cyclostationary input with a unique cyclic frequency, and that the log spectrum of the second order component of this input is frequentially smooth, as will be explained. Such systems include vehicles with internal combustion engines as the vibration from such an engine exhibits cyclostationary statistics. In this thesis, the technique is applied to a laboratory test rig and a passenger train both using an artificial input, and to a race car using the engine as the excitation. By combining cyclostationary signal processing and the concept of the cepstrum, the technique identifies the resonances and anti-resonances in the transfer functions between each response and the cyclostationary source. These resonances and antiresonances can be used to regenerate Frequency Response Functions (FRFs) and it is shown how the unknown scaling of the system can be recovered by employing finite element model updating in conjunction with this regeneration. In addition, the contribution made to model updating by the anti-resonances is also investigated. Finally, the potential of OMA to inform a model updating process is demonstrated using an experimental case study on a diesel railcar.
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Li, Yi Yuan. "Direct finite element model updating using incomplete modal data inspired from system control." Thesis, University of Macau, 2017. http://umaclib3.umac.mo/record=b3691080.

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Zweber, Jeffrey Vincent. "A method for structural dynamic model updating via the estimation of damping parameters." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/12447.

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Nichols, Jonathan Tyler. "Application of Load Updating to a Complex Three Dimensional Frame Structure." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78274.

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This thesis presents a novel method for the correlation of FEM results to experimental test results known as the "Load updating method." Specifically, the load updating method uses the math model from the FEM and the strains measured from experimental or flight test data as inputs and then predicts the loads in the FEM which would result in strains that would correlate best to the measured strains in the least squared sense. In this research, the load updating method is applied to the analysis of a complex frame structure whose validation is challenging due to the complex nature of its structural behavior, load distributions, and error derived from residual strains. A FEM created for this structure is used to generate strain data for thirty-two different load cases. These same thirty-two load cases are replicated in an experimental setup consisting of the frame, supporting structure, and thirty actuators which are used to load the frame according to the specifications for each of the thirty-two load conditions. A force-strain matrix is created from the math model in NASTRAN using unit loads which are separately applied to each load point in order to extract strain results for each of the locations of the seventy-four strain gages. The strain data from the structural test and the force-strain matrix is then input into a Matlab code which is created to perform the load updating method. This algorithm delivers a set of coefficients which in turn gives the updated loads. These loads are applied to the FEM and the strain values extracted for correlation to the strains from test data. It is found that the load updating method applied to this structure produces strains which correlate well to the experimental strain data. Although the loads found using the load updating method do not perfectly match those which are applied during the test, this error is primarily attributed to residual strains within the structure. In summary, the load updating method provides a way to predict loads which, when applied to the FEM, would result in strains that correlate best to the experimental strains. Ultimately, this method could prove especially useful for predicting loads in experimental and flight test structures and could aid greatly in the Federal Aviation Administration (FAA) certification process.<br>Master of Science
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Choi, Jiduck. "Investigation of the dynamic behavior of a cable-harnessed structure." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/49114.

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To obtain predictive modeling of a spacecraft, the author investigates the effects of adding cables to a simple structure with the goal of developing an understanding of how cables interacting with a structure. In this research, the author presents predictive and accurate modeling of a cable-harnessed structure by means of the Spectral Element Method (SEM). A double beam model is used to emulate a cable-harnessed structure. SEM modeling can define the location and the number of connections between the two beams in a convenient fashion. The proposed modeling is applied and compared with the conventional FEM. The modeling approach was compared to and validated by measurement data. The validated modeling was implemented to investigate the effect of the number of connections, of the spring stiffness of interconnections, and of mass portion of an attached cable. Damping has an important role in structural design because it reduces the dynamic response, thereby avoiding excessive deflection or stress, fatigue loads, and settling times. Experimental results with some specimens indicate a clear change of damping on the main structure with the inclusion of cable dynamics. The author investigated the modification of the damping of the host structure induced by various attached cables. The identification of a damping matrix is performed using measured data. The effect of the flexibility of a cable harness on damping is observed through experiments with various types of cables. The effect of the number of connections on damping is also investigated by changing the number of connections. Moreover, to overcome the sensitivity to noise in measured data of damping matrix identification approach, various methods are compared with a simulated lumped model and real test results. An improved damping matrix identification approach is proposed and can generate the unique damping matrix over the full frequency range of interest.<br>Ph. D.
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Karaagacli, Taylan. "Determination Of Dynamically Equivalent Fe Models Of Aircraft Structures By Using Modal Test Data." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612522/index.pdf.

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Reliable flutter analysis of aircraft structures is a major requirement to determine safe flight envelops. Dynamically equivalent finite element model of an aircraft structure correlating well with experimental modal is a major requirement for a reliable flutter analysis. Currently available model updating techniques require enormous time and engineering work to achieve appropriate finite element models of aircraft structures. The method developed within the scope of this thesis work aims to remove important disadvantages of common model updating procedures. In doing this, the method starts with a simple finite element mesh obtained by connecting measurement points, used in the Ground Vibration Test of an aircraft structure, with 3 D Euler-Bernoulli beam elements. Initial estimates of the geometric and material properties are determined by solving structural identification equations derived from the mass and stiffness orthogonality of experimental modes. By using those initial estimates, an initial finite element model is constructed. Starting from this initial finite element model, structural identification equations are updated and solved iteratively by using experimental natural frequencies and eigenvectors of the v updated finite element model representing the same mode shapes with measured normal modes. Iterations are continued until eigen solution of the updated finite element model closely correlates with experimental modal data. The applicability of the method is illustrated on a scaled aircraft model and a real aircraft structure. The results are quite satisfactory but the method requires further improvements to achieve a much better correlation level in case of real aircraft structures.
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Phillips, Peter Louis. "Integrated Multiaxial Experimentation and Constitutive Modeling." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1492598070791388.

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Ahuja, Kapil. "Recycling Krylov Subspaces and Preconditioners." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/29539.

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Science and engineering problems frequently require solving a sequence of single linear systems or a sequence of dual linear systems. We develop algorithms that recycle Krylov subspaces and preconditioners from one system (or pair of systems) in the sequence to the next, leading to efficient solutions. Besides the benefit of only having to store few Lanczos vectors, using BiConjugate Gradients (BiCG) to solve dual linear systems may have application-specific advantages. For example, using BiCG to solve the dual linear systems arising in interpolatory model reduction provides a backward error formulation in the model reduction framework. Using BiCG to evaluate bilinear forms -- for example, in the variational Monte Carlo (VMC) algorithm for electronic structure calculations -- leads to a quadratic error bound. Since one of our focus areas is sequences of dual linear systems, we introduce recycling BiCG, a BiCG method that recycles two Krylov subspaces from one pair of dual linear systems to the next pair. The derivation of recycling BiCG also builds the foundation for developing recycling variants of other bi-Lanczos based methods like CGS, BiCGSTAB, BiCGSTAB2, BiCGSTAB(l), QMR, and TFQMR. We develop a generalized bi-Lanczos algorithm, where the two matrices of the bi-Lanczos procedure are not each other's conjugate transpose but satisfy this relation over the generated Krylov subspaces. This is sufficient for a short term recurrence. Next, we derive an augmented bi-Lanczos algorithm with recycling and show that this algorithm is a special case of generalized bi-Lanczos. The Petrov-Galerkin approximation that includes recycling in the iteration leads to modified two-term recurrences for the solution and residual updates. We generalize and extend the framework of our recycling BiCG to CGS, BiCGSTAB and BiCGSTAB2. We perform extensive numerical experiments and analyze the generated recycle space. We test all of our recycling algorithms on a discretized partial differential equation (PDE) of convection-diffusion type. This PDE problem provides well-known test cases that are easy to analyze further. We use recycling BiCG in the Iterative Rational Krylov Algorithm (IRKA) for interpolatory model reduction and in the VMC algorithm. For a model reduction problem, we show up to 70% savings in iterations, and we also demonstrate that solving the problem without recycling leads to (about) a 50% increase in runtime. Experiments with recycling BiCG for VMC gives promising results. We also present an algorithm that recycles preconditioners, leading to a dramatic reduction in the cost of VMC for large(r) systems. The main cost of the VMC method is in constructing a sequence of Slater matrices and computing the ratios of determinants for successive Slater matrices. Recent work has improved the scaling of constructing Slater matrices for insulators, so that the cost of constructing Slater matrices in these systems is now linear in the number of particles. However, the cost of computing determinant ratios remains cubic in the number of particles. With the long term aim of simulating much larger systems, we improve the scaling of computing determinant ratios in the VMC method for simulating insulators by using preconditioned iterative solvers. The main contribution here is the development of a method to efficiently compute for the Slater matrices a sequence of preconditioners that make the iterative solver converge rapidly. This involves cheap preconditioner updates, an effective reordering strategy, and a cheap method to monitor instability of ILUTP preconditioners. Using the resulting preconditioned iterative solvers to compute determinant ratios of consecutive Slater matrices reduces the scaling of the VMC algorithm from O(n^3) per sweep to roughly O(n^2), where n is the number of particles, and a sweep is a sequence of n steps, each attempting to move a distinct particle. We demonstrate experimentally that we can achieve the improved scaling without increasing statistical errors.<br>Ph. D.
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Ao, Wai Kei. "Electromagnetic damping for control of vibration in civil structures." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/31145.

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This thesis investigates an alternative solution to deal with the civil structure vibration. Non-contact electromagnetic or Eddy current damping is selected as a score of vibration suppression. Electromagnetic damping relies on the interaction between a permanent magnet and conductor. An electromagnetic damper (EMD) is applied both to a laboratory footbridge structure and 6-storey model-scale aluminium moment resisting frame (AMRF). In this first study the EMD is connected in series with an electronic shunt circuit to construct an electromagnetic shunt damper (EMSD). A robust optimisation method is applied to develop the corresponding optimal design formula of the EMSD. The principle of an EMSD is to convert mechanical energy to electrical energy. Hence, the induced electromotive force (emf) is generated by electromagnetic induction. This emf induces an amount of shunt damping, which is fedback to the structure to achieve vibration suppression. It was found that when the impedance was applied, the shunt damping feature was of a similar nature to viscous dampers. In contrast, when an RLC (resistance-inductance-capacitance) circuit is connected, the shunt damping is analogous to a tuned mass damper. A second form of EMD is Eddy current damper (ECD), which relies on a geometrical arrangement of permanent magnets and conductors to produce damping forces. The vertical and horizontal orientation of the magnet, unidirectional and alternative pole projection and moving different direction of the conductor are investigated. A theoretical study involving the infinite boundary and finite boundary (the method of images current) is carried out to obtain an analytical calculation of the damping force. On the basis of this analysis, one type of ECD prototype was physically built. A performance test was carried out to determine the damping characteristics of the ECD, which agreed with the results of the numerical analysis. In addition, the ECD was applied to control the dynamics of the 6-storey AMRF. It was found that, the ECD can effectively increase system damping and have a satisfactory control effect.
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Lindemann, Sylvester. "Model updating an einem biegeelastischen Rotor." Kassel : Kassel Univ. Press, 2009. http://d-nb.info/994839081/34.

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Books on the topic "Model updating method"

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Friswell, M. I. Finite element model updating in structural dynamics. Kluwer Academic Publishers, 1995.

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Craig, Roy R. Substructure system identification for finite element model updating: Final report, NASA grant no. NAG8-1130. Center for Aeronautical Research, Bureau of Engineering Research, the University of Texas at Austin, 1997.

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Groshev, Igor', and Andrey Zheregelya. Managing an organization's digital transformation in the context of the emerging data economy. INFRA-M Academic Publishing LLC., 2025. https://doi.org/10.12737/2150883.

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The monograph is devoted to the problem of managing the digital transformation of an organization in the context of the formation of the digital ecosystem of the modern economy. The digital transformation of socio-economic systems, the business sphere, and social life has become dominant in Russian society in recent years, accelerating commercial and business interaction, accelerating the economy, and forming new communication flows. It is based on the methodology of an integrated approach and system analysis. The theoretical basis is the publications of domestic and foreign scientists and practitioners, the central issue of which is the development of theoretical, methodological and practical approaches to managing the digital transformation of an organization. The methods of comparative analysis, the method of expert assessments, normative and logical methods are chosen as research methods. The analysis of methods, mechanisms, tools and other aspects of updating the digital transformation track of Russian organizations and companies is carried out. Based on and summarizing the research results, a competence-based management approach to the digital transformation of an organization has been developed and a system model of its digital transformation has been proposed, a methodological approach to factor-based competence assessment of the level of digital readiness of organizations has been substantiated, and practical recommendations for the implementation of systemic digital organizational initiatives have been formulated. It is intended for managers, specialists and economists researching issues related to digital issues, graduate students and undergraduates engaged in research in the field of digital economy, as well as all those who are interested in this scientific field.
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Steyerberg, Ewout W. Clinical prediction models: A practical approach to development, validation, and updating. Springer, 2009.

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Marwala, Tshilidzi. Finite Element Model Updating Using Computational Intelligence Techniques: Applications to Structural Dynamics. Springer, 2010.

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Marwala, Tshilidzi. Finite Element Model Updating Using Computational Intelligence Techniques: Applications to Structural Dynamics. Springer, 2014.

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Marwala, Tshilidzi, Sondipon Adhikari, and Ilyes Boulkaibet. Probabilistic Finite Element Model Updating Using Bayesian Statistics: Applications to Aeronautical and Mechanical Engineering. Wiley & Sons, Limited, John, 2016.

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Marwala, Tshilidzi, Sondipon Adhikari, and Ilyes Boulkaibet. Probabilistic Finite Element Model Updating Using Bayesian Statistics: Applications to Aeronautical and Mechanical Engineering. Wiley & Sons, Limited, John, 2016.

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Marwala, Tshilidzi, Sondipon Adhikari, and Ilyes Boulkaibet. Probabilistic Finite Element Model Updating Using Bayesian Statistics: Applications to Aeronautical and Mechanical Engineering. Wiley & Sons, Incorporated, John, 2016.

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Marwala, Tshilidzi, Sondipon Adhikari, and Ilyes Boulkaibet. Probabilistic Finite Element Model Updating Using Bayesian Statistics: Applications to Aeronautical and Mechanical Engineering. Wiley & Sons, Incorporated, John, 2016.

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Book chapters on the topic "Model updating method"

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Mottershead, John E., Michael Link, Tiago A. N. Silva, Yves Govers, and Hamed Haddad Khodaparast. "The Sensitivity Method in Stochastic Model Updating." In Mechanisms and Machine Science. Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-09918-7_5.

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Weng, Shun, Hongping Zhu, and Yong Xia. "Substructuring Method for Finite Element Model Updating." In Engineering Applications of Computational Methods. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-1369-5_9.

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Mottershead, John, and Sifeng Bi. "Model Updating: Sensitivity Method and Bayesian Inference." In CISM International Centre for Mechanical Sciences. Springer Nature Switzerland, 2025. https://doi.org/10.1007/978-3-031-89979-9_2.

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Weng, Shun, Hongping Zhu, and Yong Xia. "Model Updating of Nonlinear Structures Using Substructuring Method." In Engineering Applications of Computational Methods. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-1369-5_14.

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Yang, Jiahua, and Yi Zheng. "Quantifying Uncertainties in Model Updating Following Bayesian Approach Using a Parameter Space-Search Algorithm." In Lecture Notes in Civil Engineering. Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-2417-8_8.

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AbstractModel updating aims to provide accurate models to reveal possible structural damage information for structural health monitoring (SHM). Uncertainties always exist in model updating due to incomplete information in measurement and modeling. These uncertainties usually cause the problem of non-uniqueness, i.e., multiple equivalent models can fit the experimental data the same well. Locating all these equivalent models and including them for representing structural dynamics is a challenging task. This work employs a Bayesian probabilistic framework for model updating, so that the uncertainties can be quantified, and thus all of the multiple equivalent models can be considered naturally. A parameter space-search algorithm is proposed to systematically locate all the equivalent models. A transmission tower under laboratory conditions with limited modal parameters was used to valid the proposed method.
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Zhou, Shanglian, and Wei Song. "A Finite Element Model Updating Method Considering Environmental Impacts." In Topics in Modal Analysis & Testing, Volume 10. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30249-2_28.

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Mottershead, John E., H. Haddad Khodaparast, R. P. Dwight, and K. J. Badcock. "Stochastic Model Updating: Perturbation, Interval Method and Bayesian Inference." In Springer Proceedings in Physics. Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-2069-5_2.

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Shi, Sumu, Cong Peng, Bei Li, Junyi Liu, Sijia Yu, and Zheyan Ji. "A Self-updating Digital Model Method for Aero-Engines." In Lecture Notes in Electrical Engineering. Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-96-2204-7_26.

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Yang, Jiahua, and En-Jie Meng. "A New Bayesian Method for Dynamic System Identification Using FFT Data." In Lecture Notes in Civil Engineering. Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-2417-8_7.

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AbstractDynamic system identification is an important field of research focused on identifying accurate system models of structures for predicting dynamic behaviors. This field finds widespread application in downstream research such as response prediction, structural failure and reliability analysis, and related areas of structural health monitoring. Conventional methods update structural finite element models (FEMs) using experimental modal parameters, because excitations are difficult to measure for full-scale structures and measured responses cannot be used as data in model updating. One challenge of conventional methods is thus that additional time is required for modal analysis, and by packing response data into modal parameters, original information in response data may be lost and cannot be used for model updating. Concerning this issue, this paper develops a dynamical system identification method to directly update an FEM using experimental fast Fourier transform (FFT) data following a Bayesian approach. The modeling of FFTs combing FEM and an efficient algorithm for processing the large amount of FFTs are not available for conventional methods. In this paper, the posterior probability density function (PDF) of the model parameters is derived assuming that FFTs at different frequency. instances follow independent and identically distributed complex Gaussian distributions under the long-data condition. One contribution of this work is that the sub-structure FEM analysis is integrated into the formulation of the posterior PDF to make the direct use of FFT data possible, and increase computational efficiency. The most probable values (MPVs) of the model parameters are obtained by maximizing the posterior PDF. By making use of the special mathematical structure of the posterior PDF, a novel algorithm that iterates among the model parameters is developed to efficiently search parameter space for the maximization. A numerical case has demonstrated that the proposed method can accurately identify the FEM of the target structure together with the unmeasured excitation parameters and damping ratios.
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Sehgal, Shankar, and Harmesh Kumar. "Damage Detection Using Derringer’s Function based Weighted Model Updating Method." In Structural Health Monitoring, Volume 5. Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-04570-2_27.

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Conference papers on the topic "Model updating method"

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Li, Yongzhi, Erming He, Chunping Zhou, Menghan Yin, and Fanglong Wang. "An efficient model updating method for multilayer thermal insulation structures based on surrogate model." In First Aerospace Frontiers Conference (AFC 2024), edited by Han Zhang. SPIE, 2024. http://dx.doi.org/10.1117/12.3032406.

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Dos Santos Souza, Luiz Fernando. "Composite plates model updating using Kriging method." In 24th ABCM International Congress of Mechanical Engineering. ABCM, 2017. http://dx.doi.org/10.26678/abcm.cobem2017.cob17-0326.

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Deng, Lu, and C. S. Cai. "Bridge Model Updating Using Response Surface Method." In 12th Biennial International Conference on Engineering, Construction, and Operations in Challenging Environments; and Fourth NASA/ARO/ASCE Workshop on Granular Materials in Lunar and Martian Exploration. American Society of Civil Engineers, 2010. http://dx.doi.org/10.1061/41096(366)213.

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Jung, Hunsang, Youngjin Park, and K. C. Park. "Mode Decoupling Controller for Feedback Model Updating." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-59697.

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A novel concept of feedback loop design for modal test and model updating is proposed. This method uses the closed-loop frequency information for parameter modifications to overcome the problems associated with the conventional methods employing the modal sensitivity matrix. To obtain new modal information from the closed-loop system, controllers should be effective in changing modal data while guaranteeing the stability of the closed-loop system. The present paper proposes a mode-decoupling controller that can alter a target mode while guaranteeing the stability of the closed-loop, and that can be constructed by using the measured open-loop, mode shapes. A simulation based on time domain input/output data is performed to evaluate the feasibility of the proposed control method, which is subsequently corroborated via experiments. Experimental data obtained on a beam via the proposed mode-decoupling controller have been applied to estimate thicknesses of a beam. The results show that the proposed approach outperforms conventional methods with a far less number of data set for the estimation of system parameters.
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Xianmin, Zhang. "A Singular-Value Decomposition Method for Updating the Analytical Model." In ASME 1997 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/detc97/vib-4152.

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Abstract Based on the theory of singular-value decomposition and the matrix approximation technique, an analytical model updating method using the identified model parameters is developed. Firstly, The identified modal matrix is decomposed by means of singular-value decomposition technique. The general updating equations for the analytical model are obtained according to the decomposition results, the eigenequation of the system, and the modal orthogonality relations. Secondly, the best matrix approximation solution for the updating equations is definited. The existence and uniqueness of the best approximation relative to the analytical model are studied. The concrete form of the best modification and two algorithms are presented. Examples demonstrate that the analytical model modification method developed in this paper possesses high modificatory accuracy comparing with some other methods. The method possesses the ability to modify the large error models.
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Abouelainine, Abderrahim, and Patrick Morelle. "An Open Model Updating Software: Application to Car Suspension Model Updating." In ASME 2000 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/detc2000/dac-14513.

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Abstract The open model updating software described here is built on a quadratic programming method with a sensitivity analysis, for constrained optimization problem with bounded variables. The updating software is tested here with a numerical car suspension model in the objective to minimize the deviation between measures and simulations. The appropriate results obtained here show the efficiency of the updating software.
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Collignon, Philippe, and Jean-Claude Golinval. "Reliable Mode Shape Expansion Method for Error Localisation and Model Updating." In ASME 1997 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/detc97/vib-4145.

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Abstract Failure detection and model updating using structural model are based on the comparison of an appropriate indicator of the discrepancy between experimental and analytical results. The reliability of the expansion of measured mode shapes is very important for the process of error localization and model updating. Two mode shape expansion techniques are examined in this paper : the well known dynamic expansion (DE) method and a method based on the minimisation of errors on constitutive equations (MECE). A new expansion method based on some improvements of the previous techniques is proposed to obtain results that are more reliable for error localisation and for model updating. The relative performance of the different expansion methods is demonstrated on the example of a cantilever beam.
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Sung, Heejun, Seongmin Chang, and Maenghyo Cho. "Reduction method based structural model updating method via neural networks." In AIAA Scitech 2020 Forum. American Institute of Aeronautics and Astronautics, 2020. http://dx.doi.org/10.2514/6.2020-1445.

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Marwala, Tshilidzi. "Finite Element Model Updating Using Response Surface Method." In 45th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics & Materials Conference. American Institute of Aeronautics and Astronautics, 2004. http://dx.doi.org/10.2514/6.2004-2005.

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Kashama Guzunza, Mohammed, Ozgur Ozcelik, Umut Yucel, and Ozgur Girgin. "Application of Optimization Based Finite Element Model Updating Method On 3d Printed Model Structures." In 2nd International Conference on Research in Science, Engineering and Technology. Acavent, 2019. http://dx.doi.org/10.33422/2nd.icrset.2019.11.780.

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Nowadays it becomes trend in studying of dynamic behavior on complex structure. Model updating is one of the tools developed for verifying accuracy of finite element models. In this paper, method for computing model updating on finite element model and effective the experimental modal analysis of structural systems is developed. The identification method developed in this study is based on time-domain system identification numerical techniques. The case study considered in this work is a 3D printed structure that be modeled as a two-story shear building system with irregular torsion. A preliminary numerical model of the two-story shear building system is developed by using SAP2000 and the experimental modal parameters data are collected in the laboratory buy some test then are modeled by Artemis modal pro. After obtaining the results from numerical modal and experimental modal, it was brought to FEMtools software to improve the match between the dynamic properties of an initial structure and the experimentally estimated modal data for updating. After updating, it’s shown that optimization was done, that some unknown material parameters (such as mass density and young modulus) of materials and/or boundary conditions were optimized by FEMtools Optimization that provides the possibility to perform design optimization on updated finite element models.
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Reports on the topic "Model updating method"

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Sridhar. L52203 Internal Corrosion Direct Assessment of Gas Transmission and Storage Lines. Pipeline Research Council International, Inc. (PRCI), 2005. http://dx.doi.org/10.55274/r0011361.

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Internal corrosion occurs where water or other corrosive electrolyte accumulates. This is the principle used in Internal Corrosion Direct Assessment (ICDA). The objective of the project is to perform field validation of the dry gas ICDA methodology and develop a wet gas ICDA methodology. The project showed that the principle of the dry-gas ICDA methodology is valid However, many uncertainties remain both in data collection as well as detailed examination. The data and model uncertainties were addressed using a probabilistic method, combined with field data using a Bayesian updating method. An approach to wet gas ICDA was indicated, but further validation was not within the scope of this project.
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Maydykovskiy, Igor, and Petras Užpelkis. The Physical Essence of Time. Intellectual Archive, 2020. http://dx.doi.org/10.32370/iaj.2450.

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The article considers the model of the space-frequency-time continuum, according to which the physical essence of Time is manifested as a fraction of electromagnetic energy spent on updating a material object in a cyclic process of copying-incarnation. For all structural levels of physical reality, the value of this fraction is a fundamental constant, which can be represented as the tangent of the loss angle, or expressed in radians, as the angle of inclination of the evolutionary spiral, which characterizes the rate of change of states or the duration of events and processes. The value of this constant can be calculated, and its value turns out to be identically equals to the square of the fine structure Constant (α2). The description of the method for identifying a new constant allows us to present the formula of Scientific Discovery as the Physical Essence of Time.
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McKay, S., Nate Richards, and Todd Swannack. Ecological model development : evaluation of system quality. Engineer Research and Development Center (U.S.), 2022. http://dx.doi.org/10.21079/11681/45380.

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Ecological models are used throughout the US Army Corps of Engineers (USACE) to inform decisions related to ecosystem restoration, water operations, environmental impact assessment, environmental mitigation, and other topics. Ecological models are typically developed in phases of conceptualization, quantification, evaluation, application, and communication. Evaluation is a process for assessing the technical quality, reliability, and ecological basis of a model and includes techniques such as calibration, verification, validation, and review. In this technical note (TN), we describe an approach for evaluating system quality, which generally includes the computational integrity, numerical accuracy, and programming of a model or modeling system. Methods are presented for avoiding computational errors during development, detecting errors through model testing, and updating models based on review and use. A formal structure is proposed for model test plans and subsequently demonstrated for a hypothetical habitat suitability model. Overall, this TN provides ecological modeling practitioners with a rapid guide for evaluating system quality.
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Secan, James A. An Investigation of Methods for Updating Ionospheric Scintillation Models Using Topside In-Situ Plasma Density Measurements. Defense Technical Information Center, 1991. http://dx.doi.org/10.21236/ada243378.

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Engel, Bernard, Yael Edan, James Simon, Hanoch Pasternak, and Shimon Edelman. Neural Networks for Quality Sorting of Agricultural Produce. United States Department of Agriculture, 1996. http://dx.doi.org/10.32747/1996.7613033.bard.

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The objectives of this project were to develop procedures and models, based on neural networks, for quality sorting of agricultural produce. Two research teams, one in Purdue University and the other in Israel, coordinated their research efforts on different aspects of each objective utilizing both melons and tomatoes as case studies. At Purdue: An expert system was developed to measure variances in human grading. Data were acquired from eight sensors: vision, two firmness sensors (destructive and nondestructive), chlorophyll from fluorescence, color sensor, electronic sniffer for odor detection, refractometer and a scale (mass). Data were analyzed and provided input for five classification models. Chlorophyll from fluorescence was found to give the best estimation for ripeness stage while the combination of machine vision and firmness from impact performed best for quality sorting. A new algorithm was developed to estimate and minimize training size for supervised classification. A new criteria was established to choose a training set such that a recurrent auto-associative memory neural network is stabilized. Moreover, this method provides for rapid and accurate updating of the classifier over growing seasons, production environments and cultivars. Different classification approaches (parametric and non-parametric) for grading were examined. Statistical methods were found to be as accurate as neural networks in grading. Classification models by voting did not enhance the classification significantly. A hybrid model that incorporated heuristic rules and either a numerical classifier or neural network was found to be superior in classification accuracy with half the required processing of solely the numerical classifier or neural network. In Israel: A multi-sensing approach utilizing non-destructive sensors was developed. Shape, color, stem identification, surface defects and bruises were measured using a color image processing system. Flavor parameters (sugar, acidity, volatiles) and ripeness were measured using a near-infrared system and an electronic sniffer. Mechanical properties were measured using three sensors: drop impact, resonance frequency and cyclic deformation. Classification algorithms for quality sorting of fruit based on multi-sensory data were developed and implemented. The algorithms included a dynamic artificial neural network, a back propagation neural network and multiple linear regression. Results indicated that classification based on multiple sensors may be applied in real-time sorting and can improve overall classification. Advanced image processing algorithms were developed for shape determination, bruise and stem identification and general color and color homogeneity. An unsupervised method was developed to extract necessary vision features. The primary advantage of the algorithms developed is their ability to learn to determine the visual quality of almost any fruit or vegetable with no need for specific modification and no a-priori knowledge. Moreover, since there is no assumption as to the type of blemish to be characterized, the algorithm is capable of distinguishing between stems and bruises. This enables sorting of fruit without knowing the fruits' orientation. A new algorithm for on-line clustering of data was developed. The algorithm's adaptability is designed to overcome some of the difficulties encountered when incrementally clustering sparse data and preserves information even with memory constraints. Large quantities of data (many images) of high dimensionality (due to multiple sensors) and new information arriving incrementally (a function of the temporal dynamics of any natural process) can now be processed. Furhermore, since the learning is done on-line, it can be implemented in real-time. The methodology developed was tested to determine external quality of tomatoes based on visual information. An improved model for color sorting which is stable and does not require recalibration for each season was developed for color determination. Excellent classification results were obtained for both color and firmness classification. Results indicted that maturity classification can be obtained using a drop-impact and a vision sensor in order to predict the storability and marketing of harvested fruits. In conclusion: We have been able to define quantitatively the critical parameters in the quality sorting and grading of both fresh market cantaloupes and tomatoes. We have been able to accomplish this using nondestructive measurements and in a manner consistent with expert human grading and in accordance with market acceptance. This research constructed and used large databases of both commodities, for comparative evaluation and optimization of expert system, statistical and/or neural network models. The models developed in this research were successfully tested, and should be applicable to a wide range of other fruits and vegetables. These findings are valuable for the development of on-line grading and sorting of agricultural produce through the incorporation of multiple measurement inputs that rapidly define quality in an automated manner, and in a manner consistent with the human graders and inspectors.
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Serafica, Ramonette, and Queen Cel Oren. A Snapshot of Innovation in the Philippine Services Sector. Philippine Institute for Development Studies, 2024. http://dx.doi.org/10.62986/dp2024.14.

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The Philippine Development Plan 2023–2028 recognizes innovation as one of the drivers of growth in the services sector, creating a strategic framework to reinvigorate the sector and strengthen creativity and innovation. To help formulate the appropriate strategies and policies, this paper examines the evidence on innovation in service industries using the 2021 Survey of Innovation Activities of Establishments, which provided broader sector coverage. The survey was conducted during the pandemic when firms had to pivot to new modes of service delivery to survive. It gives a more nuanced profile and innovation behaviors of services firms and seeks to identify the effects and determinants of innovation across the services subsectors. Among the four types of innovation, organizational innovation was the most common type of innovation introduced in most service sectors, followed by marketing, process, and product innovation. For most of the services subsectors, the most common innovation activity of the establishments was “Training for innovative activities”. Across all services subsectors, cost factors are identified as the most common barrier considered of high significance. Organizations that employ at least one FIRe technology, obtain funding, use platforms, engage in R&amp;D activities (whether outsourced or in-house), or use knowledge management methods are more likely to be innovation active and produce at least one type of innovation. The survey also reveals greater reliance on internal and market sources of information while the utilization of institutional and other sources of information, such as incubators, scientific journals or technical publications, and regulatory bodies was low for most subsectors. Universities or other higher education institutions were also not popular cooperation partners. In terms of knowledge management, regularly updating internal databases or manuals was the most popular practice while a policy to bring in external experts from universities, research institutes, or other establishments to participate in project teams was the least common practice across the subsectors. The Philippine Innovation Act (RA 11293) provides different interventions to address the various impediments related to cost factors, knowledge factors, market factors, and legal or regulatory factors (Albert et al. 2023). Given the diversity of services, a one-size-fits-all strategy will not be effective. While this study presents a snapshot of the innovation profiles of the different subsectors, in-depth analysis of the innovation ecosystem is required to develop industry-specific innovation roadmaps.
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Tire Experimental Characterization Using Contactless Measurement Methods. SAE International, 2021. http://dx.doi.org/10.4271/2021-01-1114.

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In the frame of automotive Noise Vibration and Harshness (NVH) evaluation, inner cabin noise is among the most important indicators. The main noise contributors can be identified in engine, suspensions, tires, powertrain, brake system, etc. With the advent of E-vehicles and the consequent absence of the Internal Combustion Engine (ICE), tire/road noise has gained more importance, particularly at mid-speed driving and in the spectrum up to 300 Hz. At the state of the art, the identification and characterization of Noise and Vibration sources rely on pointwise sensors (microphones, accelerometers, strain gauges). Optical methods such as Digital Image Correlation (DIC) and Laser Doppler Vibrometer (LDV) have recently received special attention in the NVH field because they can be used to obtain full-field measurements. Moreover, these same techniques could also allow to characterize the tire behavior in operating conditions, which would be practically impossible to derive with standard techniques. In this paper we will demonstrate how non-contact full-field measurement techniques can be used to reliably and robustly characterize the tire behavior up to 300 Hz, focusing on static conditions. Experimental modal analysis will extract the modal characteristic of the tire in both free-free and statically preloaded boundary conditions, using both DIC and LDV. The extracted natural frequencies, damping ratios and full-field mode shapes will be used on one side to improve the accuracy of tire models (either by deriving FRF based models or updating FE ones) but also as a reference for future investigation on the tire behavior characterization in rotating conditions.
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