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Graphical abstract2 Highlights  ANNs-solved vibration based parametric identification studies are reviewed. Factors which affect identification result are discussed. Pros and cons of ANN approaches are mentioned. 1• Fundamentals of ANNs. 2• Dynamic behavior analysis for parametric identifications.• Reason for adopting ANNs to vibrational inverse identifications. 3• Earlier ANN approaches to different vibrational parametric identifications.--Signal pre-processing techniques --Input-output schemes --ANN models 4• Factors that affect ANNs performance for vibrational paramteric identification. 5• Advantages and disadvantages of ANN approaches. 6• Suggestions to potential researchers.• Experimental validation of authors' suggestion based on the literature.3  Suggestions are given to potential researchers based on the discussion. Analysis with experimental results is provided to justify some point of view. AbstractVibration behavior of any solid structure reveals certain dynamic characteristics and property parameters of that structure. Inverse problems dealing with vibration response utilize the response signals to find out input factors and/or certain structural properties. Due to certain drawbacks of traditional solutions to inverse problems, ANNs have gained a major popularity in this field. This paper reviews some earlier researches where ANNs were applied to solve different vibration-based inverse parametric identification problems. The adoption of different ANN algorithms, input-output schemes and required signal processing were denoted in considerable detail. In addition, a number of issues have been reported, including the factors that affect ANNs' prediction, as well as the advantage and disadvantage of ANN approaches with respect to general inverse methods. Based on the critical analysis, suggestions to potential researchers have also been provided for future scopes.

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17Force identification using inverse technique is important especially when direct measurement 18 through force transducer is not possible. Considering the effects of impact excitation force on the 19 integrity of a lightweight structure, impact force identification has become the subject of several 20 studies. A methodology utilising Operating Deflection Shape (ODS) analysis, Frequency Response 21 Function (FRF) measurement and pseudo-inverse method to evaluate the dynamic force is 22 presented. A rectangular plate with four ground supports was used as a test rig to simulate the 23 motions of a simple vehicle body. By using the measured responses at remote points that are away 24 from impact locations and measured FRFs of the test rig, unknown force locations and their time 25 histories can be recovered by the proposed method. The performance of this approach in various 26 2 cases such as under-determined, even-determined and over-determined cases was experimentally 27 demonstrated. Good and bad combinations of response locations were selected based on the 28 condition number of FRF matrix. This force identification method was examined under different 29 response combinations and various numbers of response locations. It shows that in the over-30 determined case, good combination of response locations (i.e. low average of condition number of 31 FRF matrix) and high number of response locations give the best accuracy of force identification 32 result compared to under-determined and even-determined cases. 33 34 Keywords: condition number; frequency response function; impact force identification; pseudo-35 inverse method; response combination 36 INTRODUCTION 37Identification of dynamic force excitation on a system is important for performance evaluation, 38 design optimisation, noise suppression, vibration control as well as condition monitoring. However, 39 there are many situations where the direct measurement of the excitation forces is not possible or 40 feasible. For example, engine torque pulses and shaking forces are difficult to measure since these 41 forces are distributed throughout the engine [1]. In such a case, direct measurement by using force 42 transducer is not possible due to the difficulty of installation and dynamic characteristic altering 43 problem [2]. Therefore, force identification using the inverse method has been developed widely to 44 solve the problem. Much research has been carried out to find the unknown dynamic forces by 45 using the inverse method [3 -6]. 46 Impact force is the main cause for material fatigue of many structures especially in 47 lightweight structures, so it is useful to understand the characteristics of loading profile, such as 48 impact location and its time history [7]. At the development and modification stage of a lightweight 49 structure design, better information about the loads experienced by the structure through the 50 iteration process will assist the development resulting in a better design. Identification of the input 51 3 forces and their...

Destructive identification approaches are no longer in favour ever since the existence of non-destructive evaluation approaches as they are accurate, rapid and cheap. Researchers are devoted in improving the accuracy, rate of convergence, and cost of such approaches which depend greatly on the types of vibrational experiments conducted and the types of forward and inverse methods used in numerical section. Therefore, this paper presents a review on the development of non-destructive vibrational evaluation approaches in identifying the elastic constants of composite plates, in experimental and numerical manners in order to enlighten researchers with the current trends of non-destructive vibrational approaches.