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The purpose of this paper is to focus on the influences of the uncertain dynamic responses on the reconstruction of loads.

Based on the assumption of unknown-but-bounded (UBB) noise, a time-domain approach to estimate the uncertain time-dependent external loads is presented by combining the inverse system method in modern control theory and interval analysis in interval mathematics. Inspired by the concept of set membership identification in control theory, an interval analysis model of external loads time history, which is indeed a region or feasible set containing all possible loads being consistent with the bounded structural acceleration responses is established and further solved by two interval algorithms.

Unlike traditional loads identification methods which only give a point estimation, an interval estimation of external loads time history, which is a region containing all the possible loads being consistent with the uncertain structural responses, is determined. The correlation characteristics among the responses of acceleration, velocity, and displacement are also discussed in consideration of the UBB uncertainty.

For one hand, the solution of the inverse problem in original system is transformed to the solution of the direct problem in inverse system; for another, the authors deal with the uncertainty by use of interval analysis method, and the identified interval process, which contains any possible external loads time history being consistent with the bounded structural responses can be approximately obtained.

The work loads of academic staff at the University of Queensland are analyzed and comparisons made between the work loads of staff by rank and by academic field. The analysis confirms that there are significant differences among the average work loads of staff members according to rank and goes on to reveal differences between the work loads of staff members in different groups of academic departments. The study suggests that apart from those of staff in the clinical sciences group of departments, the work loads, although different in nature, are comparable in magnitude.

This study aims to develop a new correlation method for prediction of in-flight wings deflections by integration of the experimental ground tests with computational fluid dynamics (CFD) analysis.

The ground test results are implemented in the curve fitting process to determine deflections at 66 specific points (SPs) on the front and rear wing torque box. By using the obtained deflections and the corresponding applied loads, an experimental deflection equation (EDE) for each point is established through the Castigliano’s theorem. The CFD aerodynamic loads of typical aircraft, which have been obtained earlier by the authors, are once again used in the current research. The total applied loads to each part are achieved via summation of inertia and aerodynamic loads. The obtained loads are transformed to the equivalent concentrated loads at the SPs. By substituting the concentrated load values in the EDEs, the SPs deflections are achieved for mentioned flight conditions. The resulted deflections and the corresponding input flight parameters, i.e. M and α, are incorporated into a linear regression method for development of the appropriate in-flight deflection equations (IFDEs). The validity of IFDEs is approved by comparing IFDEs’ deflections with the corresponding ones calculated through EDEs for different flight conditions.

As an alternative approach to the fairly expensive flight tests, the IFDEs can be used to predict the in-flight wing deflections with comparable degree of accuracy.

Prediction of actual wing deflections distributions without flight tests execution at any given flight condition.

The purpose of this paper was to compare the response of selected hybrid Fibre Metal Laminates (FMLs) in the form of glass and carbon fibre aluminium laminates to dynamic and static loads compared together.

The subject of examination was FMLs (Al/CFRP and Al/GFRP). The samples were subjected to low-velocity impact and quasi-static indentation. The response of laminates to the both types of loads was evaluated by comparison of force – displacement diagrams including the values of maximum forces as well as the extent and nature of structure degradation as a result of loads.

In case of Al/GFRP laminates, the analysis of characteristic relations, i.e. force – displacement and the impactor influence area in case of indentation and impact confirmed that certain parameters, i.e. the values of maximum force transferred by laminate, destruction surface area and destruction mechanisms are consistent after static and dynamic tests. Significant differences were found in destruction scale in Al/GFRP laminates despite considerable fitting of force – displacement diagrams to static and dynamic tests. Destruction surface area observed in FML carbon laminates subjected to dynamic loads was significantly smaller than after indentation but perforation area occurring at the unloaded side was much more extensive.

Research issues in the scope of dynamic loads by means of concentrated force in composite materials and interpretation of the effects of their impacts are extremely complex. Therefore, the attempts are made to predict the resistance to dynamic loads by means of concentrated force using statistical research methods. The test results might be useful for the design and simulations of FMLs applications in aerospace.

From the analysis of available literature, it appears that there are no studies exploring the issue of forecasting or comparison the effects of static and dynamic tests for hybrid FMLs. The new hybrid materials like FMLs have different mechanisms of damage initiation and propagation as a result of impact, in comparison to classic composite materials. It means that possibilities of using the static loads to predict impact resistance should be known well for all type of FMLs. Actually, there is no research about static indentation in relation to low-velocity impact of aluminium-carbon laminates. This situation encouraged the authors of the present study to undertake research in this scope. The results can demonstrate and explain why prediction of impact resistance of FMLs by using static indentation is uncertain and not always valuable.

To present a method of interaction between flight loads that is applied to a probabilistic damage tolerance analysis in an acrobatic aircraft.

The uncertainties concerning material strength, initial crack size and loads in the aircraft are considered. We place special emphasis on stress distribution, using superposition criteria that distinguish between gust, maneuver and ground‐air‐ground loads. Gust load is generated form its power spectral density and modified using service load data (exceedance curves). Crack initiation time and propagation time are considered in calculating the service time.

A new and realistic method of interaction between loads during acrobatic flight is proposed. This method was compared with other methods in an example. The effects of the interaction criteria are related to the influence between loads (stress levels and frequency).

In commercial aircraft, maneuver loads have a lower influence than gust loads, and the mission concept is the correct approach. Training aircraft have the opposite king of behavior and the proposed superposition method is shown to be better approach. This method would have more pronounced effects in aircraft types with behaviors between commercial and training (for example, amphibious aircraft).

This paper aims to automatically generate load shedding sequences due to insufficient power supply, to ensure flight safety and complete flight task.

In this paper, a power allocation and load management model, including logical and physical submodels of the distribution system, is first established according to different requirements of the loads in different flight phase and the current total power supply. Then, an optimal load management scheme based on an improved ant colony algorithm is proposed to automatically generate load shedding sequences for both safety-critical and nonsafety critical loads, to achieve a reliable and safe power supply.

To verify the efficiency and feasibility of the algorithm, the proposed method is verified in a virtual simulation platform. Simulation result illustrates that the proposed algorithm is efficient and feasible.

The proposed method can provide guidance on load power supply when the civil aircraft is under abnormal power supply situation.

An optimal load management scheme is proposed by considering different requirements of the loads in different flight phase and the current total power supply.

The resistance of steel plate shear walls (SPSW) under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the conventional weapons effect program (CONWEP) model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a multiple linear regression (MLR), multiple Ln equation regression (MLnER), gene expression programming (GEP), adaptive network-based fuzzy inference (ANFIS) and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads.

The SPSW under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the CONWEP model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a MLR, MLnER, GEP, ANFIS and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads.

The resistance of SPSW under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the CONWEP model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a MLR, MLnER, GEP, ANFIS and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads.

The resistance of SPSW under explosive loads is evaluated using nonlinear FE analysis and surrogate methods. This study uses the CONWEP model for the explosive load and the Johnson-Cook model for the steel plate. Based on the Taguchi method, 25 samples out of 100 samples are selected for a parametric study where we predict the damaged zones and the maximum deflection of SPSWs under explosive loads. Then, this study uses a MLR, MLnER, GEP, ANFIS and an ensemble model to predict the maximum detection of SPSWs. Several statistical parameters and error terms are used to evaluate the accuracy of the different surrogate models. The results show that the cross-section in the y-direction and the plate thickness have the most significant effects on the maximum deflection of SPSWs. The results also show that the maximum deflection is related to the scaled distance, i.e. for a value of 0.383. The ensemble model performs better than all other models for predicting the maximum deflection of SPSWs under explosive loads.

A Discussion concerning the Use of Wind Tunnel Results and Flight Test Measurements in the Prediction of Aerodynamic Loads for Stressing Purposes in the Aerodynamics Department of the Weybridge Division of British Aircraft Corporation. The responsibility for the prediction and issue of aerodynamic loads for stressing purposes at the Weybridge Division of British Aircraft Corporation is carried by the Aerodynamics Department. The arguments for and against this arrangement are briefly examined. One of the main arguments in favour is the facility with which wind tunnel tests can be instigated and controlled. The use of wind tunnel tests specifically designed to give aerodynamic loading data and their relation to estimation using theoretical and semi‐empirical methods is fully discussed and illustrated. The confirmation of design estimates by full scale in‐flight load measurement is described and the usefulness of in‐flight measurements as a design tool on subsequent aircraft of a similar type is discussed.

The properties of materials under impact load are introduced in terms of metal, nonmetallic materials and composite materials. And the application of impact load research in biological fields is also mentioned. The current hot research topics and achievements in this field are summarized. In addition, some problems in theoretical modeling and testing of the mechanical properties of materials are discussed.

The situation of materials under impact load is of great significance to show the mechanical performance. The performance of various materials under impact load is different, and there are many research methods. It is affected by some kinds of factors, such as the temperature, the gap and the speed of load.

The research on mechanical properties of materials under impact load has the characteristics as fellow. It is difficult to build the theoretical model, verify by experiment and analyze the data accumulation.

This review provides a reference for further study of material properties.

The equation of motion of a beam on multiple supports, subject to prescribed time‐dependent conservative axial loads, is formulated based on Hamilton’s principle and the assumed mode method. The effects of sinusoidal perturbations in respect of the axial loads are then examined using Bolotin’s method. The respective regions of instability are determined by converting the resulting equations of boundary frequencies into the standard form of a generalized eigenvalue problem. Instability regions are presented for various combinations of support configuration, average value and amplitude of the sinusoidal perturbations of the axial loads.