윤호준 교수

Summary It is well known that the sensitivity analysis of the eigenvectors corresponding to multiple eigenvalues is a difficult problem. The main difficulty is that for given multiple eigenvalues, the eigenvector derivatives can be computed for a specific eigenvector basis, the so‐called adjacent eigenvector basis. These adjacent eigenvectors depend on individual variables, which makes the eigenvector derivative calculation elaborate and expensive from a computational perspective. This research

Metamaterials that can be used in manipulating wave propagation have been shown in previous research. However, existing methods for controlling the propagation of shear waves remain a challenge. By combining the principle of wave destructive interference and the design concept of the gradient‐index phononic crystals, here new functionally graded phononic crystals with broadband gap for controlling shear wave propagation are presented. The proposed functionally graded phononic crystals are formed

This paper presents a new dynamic absorber attenuating the vibrations at three resonance frequencies simultaneously. The dynamic vibration responses of mechanical systems with dynamic absorbers are mainly influenced by how close the eigenfrequencies of the installed dynamic absorbers are to the eigenfrequencies of the hosting structure. To suppress structural vibration at single target frequency, it is enough to install a single mass tuned dynamic absorber whose eigenfrequency is tuned to the ex

We present the concept design of a new class of acoustic metamaterial structure based on a combined heterogeneous double-split hollow sphere (CHDSHS). These structures are local resonators possessing subwavelength band gaps. The present CHDSHS metamaterial structures are made of plastic sphere structures with two different holes. The main novelty of a CHDSHS relies in the significant noise reduction obtained and the simplicity of manufacture. Their characteristics in band gaps are influenced by

A new structure with a bidirectional negative stiffness (BNS) value utilizing buckling phenomena (often called bi-stable or snap-through) and a mechanical diode are presented with regard to mechanical metamaterial applications. The need for cost and mass efficient vibration isolation parts within the modern aerospace, automotive, and civil industries has been the subject of many interesting studies in the last several decades. With conventional materials in nature, many innovative approaches hav