Tabela A z publikacjami w czasopismach wyróżnionych w Journal Citation Reports (JCR) 
Tabela B z publikacjami w czasopismach zagranicznych i krajowych, wyróżnionych na liście MNSzW
Publikacje konferencyjne indeksowane w bazie Web of Science Core Collection
Inne publikacje w pozostałych czasopismach i wydawnictwach konferencyjnych
Afiliacja IPPT PAN

1.Chikahiro Y., Ario I., Pawłowski P., Graczykowski C., Holnicki-Szulc J., Optimization of reinforcement layout of scissor-type bridge using differential evolution algorithm, Computer-Aided Civil and Infrastructure Engineering, ISSN: 1093-9687, DOI: 10.1111/mice.12432, pp.1-16, 2019
Chikahiro Y., Ario I., Pawłowski P., Graczykowski C., Holnicki-Szulc J., Optimization of reinforcement layout of scissor-type bridge using differential evolution algorithm, Computer-Aided Civil and Infrastructure Engineering, ISSN: 1093-9687, DOI: 10.1111/mice.12432, pp.1-16, 2019

Abstract:
Scissors mechanisms are commonly used in safety engineering during the construction of temporary structures, owing to their inherent advantages of foldability, transformability, and reusability.We effectively utilized these scissors mechanism features to develop a lightweight, deployable emergency Mobile Bridge (MB) based on optimization, and control of the folding structure. Here, we discuss the problems of optimal reinforcement layout for the MB by formulating and solving three optimization problems, namely: (a) the load capacity maximization problem, (b) the weight minimization problem, and (c) coupling the load capacity maximization problem and the weight minimization problem. The potential benefits resulting from the application of reinforcement were evaluated using a combination of finite element analysis and an optimization algorithm based on the differential evolution method. The results demonstrate the significant positive influence of the additional reinforcing members. In particular, the limit load was increased by over 10 times, while the weight was decreased to approximately half. The proposed methodology enabled the development of a substantially improved version of the MB characterized by a higher load capacity and lower weight in comparison to the initial bridge design.

(45p.)
2.Graczykowski C., Faraj R., Development of control systems for fluid-based adaptive impact absorbers, MECHANICAL SYSTEMS AND SIGNAL PROCESSING, ISSN: 0888-3270, DOI: 10.1016/j.ymssp.2018.12.006, Vol.122, No.2019, pp.622-641, 2019
Graczykowski C., Faraj R., Development of control systems for fluid-based adaptive impact absorbers, MECHANICAL SYSTEMS AND SIGNAL PROCESSING, ISSN: 0888-3270, DOI: 10.1016/j.ymssp.2018.12.006, Vol.122, No.2019, pp.622-641, 2019

Abstract:
The paper presents development, evaluation and comparison of various control systems for adaptive fluid-based absorbers serving for absorption of the impact loading. The investigations concern two competitive approaches: i) standard control systems with single determination of the optimal system path based on identified impact conditions, and ii) newly-developed control systems with on-line determination and update of the system path during the process. It is revealed that low robustness of the standard control systems to imprecise impact identification and unknown disturbances results from the assumed path-determination approach and utilized simple path-tracking methods. The proposed solution to this problem is application of the innovative control systems, which utilize Automatic Path Finding and Automatic Path Update algorithms based on full kinematic feedback as well as Hybrid Path Tracking method dedicated for fluid-based absorbers. The introduced approach to absorber control is used to develop three different self-adaptive systems of increasing complexity and robustness. The favourable capabilities of proposed systems including no need for impact identification, high robustness against force disturbances and reduction of leakages influence are proved. Detailed discussion is presented using the illustrative example of single-chamber adaptive pneumatic shock-absorber mitigating impact loading.

Keywords:
Adaptive Impact Absorption, Automatic Path Finding, Automatic Path Update, Full kinematic feedback, Hybrid Path Tracking, Self-adaptive system, Pneumatic shock-absorber

(45p.)
3.Pisarski D., Myśliński A., Suboptimal distributed state-feedback control of semi-active vibrating systems, JOURNAL OF SOUND AND VIBRATION, ISSN: 0022-460X, DOI: 10.1016/j.jsv.2018.12.009, Vol.443, pp.637-651, 2019
Pisarski D., Myśliński A., Suboptimal distributed state-feedback control of semi-active vibrating systems, JOURNAL OF SOUND AND VIBRATION, ISSN: 0022-460X, DOI: 10.1016/j.jsv.2018.12.009, Vol.443, pp.637-651, 2019

Abstract:
A novel semi-active control method for mitigating structural vibration is studied. The method relies on distributed state information patterns and the solution to a suboptimal control problem that aims at replicating the switched structures of the optimal open-loop stabilizing controls. The optimality conditions and the method of solution of the suboptimal problem are discussed. The performance of this method is examined by means of numerical experiments performed for a double cantilever system equipped with a set of semi-active elastomers with controlled viscoelastic properties. The experiments were carried out for different controller architectures and a series of initial conditions. In terms of the assumed objectives, the proposed distributed control strategy significantly outperforms the passive damping strategies and is competitive with a standard centralized control. The proposed approach is general to a class of bilinear control systems concerned with smart structural elements. The practical aspects of the designed distributed controller are highlighted.

Keywords:
distributed control, optimal control, bilinear system, stabilization, semi-active structure

(35p.)
4.Meissner M., Wiśniewski K., Influence of room modes on low-frequency transients: Theoretical modeling and numerical predictions, JOURNAL OF SOUND AND VIBRATION, ISSN: 0022-460X, DOI: 10.1016/j.jsv.2019.02.012, Vol.448, pp.19-33, 2019
Meissner M., Wiśniewski K., Influence of room modes on low-frequency transients: Theoretical modeling and numerical predictions, JOURNAL OF SOUND AND VIBRATION, ISSN: 0022-460X, DOI: 10.1016/j.jsv.2019.02.012, Vol.448, pp.19-33, 2019

Abstract:
In the low-frequency range, a sound reproduction in enclosures is strongly influenced by excited room modes. While the spectral impact of acoustic modes on a room response is well recognized, there is no sufficient knowledge on how these modes affects transients. In the paper this issue has been examined theoretically and numerically for a room excited by a tone burst by using a modal expansion method supported by a computer implementation. To quantify a temporal accuracy of a sound reproduction, the new metrics referred to as the tone burst reproduction error was introduced. The basis for determining this quantity was a deviation between the tone burst amplitude and the amplitude of a sound pressure computed via the Hilbert transform. A numerical simulation was performed for an irregularly shaped enclosure having a form of two-room coupled system. Calculation results have proved that a high inaccuracy of a tone burst reproduction occurs at receiving points corresponding to sharp dips in a distribution of the steady-state sound pressure level. This is because in these points an amplitude of transient sound is much bigger than a tone burst amplitude. It was discovered that strong narrow peaks in the tone burst reproduction error are located at centers of vortices in the active sound intensity vector field. An influence of a sound damping in a room on a reproduction of a tone burst was also examined and it was found that a substantial increase in a wall sound absorption does not significantly improves a tone burst reproduction because it does not eliminate sharp dips in a distribution of the steady-state sound pressure level.

Keywords:
room acoustics, room modes, transients, tone burst, discrete Hilbert transform, sound intensity vector field

(35p.)
5.Zieliński T.G., Chevillotte F., Deckers E., Sound absorption of plates with micro-slits backed with air cavities: Analytical estimations, numerical calculations and experimental validations, APPLIED ACOUSTICS, ISSN: 0003-682X, DOI: 10.1016/j.apacoust.2018.11.026, Vol.146, pp.261-279, 2019
Zieliński T.G., Chevillotte F., Deckers E., Sound absorption of plates with micro-slits backed with air cavities: Analytical estimations, numerical calculations and experimental validations, APPLIED ACOUSTICS, ISSN: 0003-682X, DOI: 10.1016/j.apacoust.2018.11.026, Vol.146, pp.261-279, 2019

Abstract:
This work discusses many practical and some theoretical aspects concerning modelling and design of plates with micro-slits, involving multi-scale calculations based on microstructure. To this end, useful mathematical reductions are demonstrated, and numerical computations are compared with possible analytical estimations. The numerical and analytical approaches are used to calculate the transport parameters for complex micro-perforated (micro-slotted) plates, which allow to determine the effective properties of the equivalent fluid, so that at the macro-scale level the plate can be treated as a specific layer of acoustic fluid. In that way, the sound absorption of micro-slotted plates backed with air cavities can be determined by solving a multi-layer system of Helmholtz equations. Two such examples are presented in the paper and validated experimentally. The first plate has narrow slits precisely cut out using a traditional technique, while the second plate - with an original micro-perforated pattern - is 3D-printed.

Keywords:
Micro-slotted plates, Micro-perforated plates, Sound absorption, Microstructure-based modelling, 3D-printing

(30p.)
6.Hou J., Wang P., Jing T., Jankowski Ł., Experimental Study for Damage Identification of Storage Tanks by Adding Virtual Masses, SENSORS, ISSN: 1424-8220, DOI: 10.3390/s19020220, Vol.19, No.2, pp.220-1-17, 2019
Hou J., Wang P., Jing T., Jankowski Ł., Experimental Study for Damage Identification of Storage Tanks by Adding Virtual Masses, SENSORS, ISSN: 1424-8220, DOI: 10.3390/s19020220, Vol.19, No.2, pp.220-1-17, 2019

Abstract:
This research proposes a damage identification approach for storage tanks that is based on adding virtual masses. First, the frequency response function of a structure with additional virtual masses is deduced based on the Virtual Distortion Method (VDM). Subsequently, a Finite Element (FE) model of a storage tank is established to verify the proposed method; the relation between the added virtual masses and the sensitivity of the virtual structure is analyzed to determine the optimal mass and the corresponding frequency with the highest sensitivity with respect to potential damages. Thereupon, the damage can be localized and quantified by comparing the damage factors of substructures. Finally, an experimental study is conducted on a storage tank. The results confirm that the proposed method is feasible and practical, and that it can be applied for damage identification of storage tanks.

Keywords:
damage identification, storage tanks, sensitivity analysis, frequency

(30p.)
7.Hou J., Li Z., Zhang Q., Zhou R., Jankowski Ł., Optimal Placement of Virtual Masses for Structural Damage Identification, SENSORS, ISSN: 1424-8220, DOI: 10.3390/s19020340, Vol.19, No.2, pp.340-1-18, 2019
Hou J., Li Z., Zhang Q., Zhou R., Jankowski Ł., Optimal Placement of Virtual Masses for Structural Damage Identification, SENSORS, ISSN: 1424-8220, DOI: 10.3390/s19020340, Vol.19, No.2, pp.340-1-18, 2019

Abstract:
Adding virtual masses to a structure is an efficient way to generate a large number of natural frequencies for damage identification. The influence of a virtual mass can be expressed by Virtual Distortion Method (VDM) using the response measured by a sensor at the involved point. The proper placement of the virtual masses can improve the accuracy of damage identification, therefore the problem of their optimal placement is studied in this paper. Firstly, the damage sensitivity matrix of the structure with added virtual masses is built. The Volumetric Maximum Criterion of the sensitivity matrix is established to ensure the mutual independence of measurement points for the optimization of mass placement. Secondly, a method of sensitivity analysis and error analysis is proposed to determine the values of the virtual masses, and then an improved version of the Particle Swarm Optimization (PSO) algorithm is proposed for placement optimization of the virtual masses. Finally, the optimized placement is used to identify the damage of structures. The effectiveness of the proposed method is verified by a numerical simulation of a simply supported beam structure and a truss structure.

Keywords:
damage identification, sensor optimization, Virtual Distortion Method (VDM), Particle Swarm Optimization (PSO) algorithm, sensitivity

(30p.)
8.Hou J., Wang S., Zhang Q., Jankowski Ł., An Improved Objective Function for Modal-Based Damage Identification Using Substructural Virtual Distortion Method, Applied Sciences, ISSN: 2076-3417, DOI: 10.3390/app9050971, Vol.9, No.5, pp.1-17, 2019
Hou J., Wang S., Zhang Q., Jankowski Ł., An Improved Objective Function for Modal-Based Damage Identification Using Substructural Virtual Distortion Method, Applied Sciences, ISSN: 2076-3417, DOI: 10.3390/app9050971, Vol.9, No.5, pp.1-17, 2019

Abstract:
Damage identification based on modal parameters is an important approach in structural health monitoring (SHM). Generally, traditional objective functions used for damage identification minimize the mismatch between measured modal parameters and the parameters obtained from the finite element (FE) model. However, during the optimization process, the repetitive calculation of structural modes is usually time-consuming and inefficient, especially for large-scale structures. In this paper, an improved objective function is proposed based on certain characteristics of the peaks of the frequency response function (FRF). Traditional objective functions contain terms that quantify modal shapes and/or natural frequencies. Here, it is proposed to replace them by the FRF of the FE model, which allows the repeated full modal analysis to be avoided and thus increases the computational efficiency. Moreover, the efficiency is further enhanced by employing the substructural virtual distortion method (SVDM), which allows the frequency response of the FE model of the damaged structure to be quickly computed without the costly re-analysis of the entire damaged structure. Finally, the effectiveness of the proposed method is verified using an eight-story frame structure model under several damage cases. The damage location and extent of each substructure can be identified accurately with 5% white Gaussian noise, and the optimization efficiency is greatly improved compared with the method using a traditional objective function.

Keywords:
structural health monitoring (SHM), damage identification, substructure, virtual distortion method (VDM), frequency response

(25p.)