This paper aims to introduce topology optimization as a robust tool for damage detection in plane stress structures. Two objective functions based on natural frequencies and shape modes of the structure are defined to minimize discrepancy between dynamic specifications of the real damaged structure and the updating model. Damage area is assumed as a porous material where amount of porosity sign...

background: the fatal effect of ionizing radiation on cells depends on linear energy transfer (let) level. the distribution of ionizing radiation is sparse and homogeneous for low let radiations such as x or γ, but it is dense and concentrated for high let radiation such as heavy-ions radiation. material and methods: chinese hamster ovary cells (cho-k1) were exposed to 4 gy fe-ion 2000 kev/m. ...

Analytical detection of cracking in connections of steel moment resisting frames using simple damage indices is important since these cracks are not visible unless the connections are uncovered. In this paper, applicability of three cumulative damage indices for detection of cracking in a cover plate welded moment connection is investigated. The damage indices considered in this study are based...

Iterative Damage Index Method for Structural Health Monitoring. (December 2009) Taesun You, B.S., Hanyang University, Seoul, South Korea Co-Chairs of Advisory Committee: Dr. Paolo Gardoni, Dr. Stefan Hurlebaus Structural Health Monitoring (SHM) is an effective alternative to conventional inspections which are time-consuming and subjective. SHM can detect damage early and reduce maintenance cost...

Image segmentation is the most challenging issue in computer vision applications. And most difficulties for crops management in agriculture are the lack of appropriate methods for detecting the leaf damage for pests’ treatment. In this paper we proposed an automatic method for leaf damage detection and severity estimation of coffee leaf by avoiding defoliation. After enhancing the contrast of t...

Structural damages can result in nonlinear dynamical responses. Thus, estimating the nonlinearities generated by damages potentially allows detecting them. In this paper, an original approach called the ES2D (Exponential Sine Sweep Damage Detection) is proposed for nonlinear damage detection. This approach is based on a damage index that reflects the ratio of the energy contained in the nonline...

This paper investigates the efficiency of Ultrasonic Pulse Velocity (UPV) method in detecting cracks and flaws inside the concrete. A series of concrete beams and slab specimens were cast and damaged to simulate the different mechanisms possible in a reinforced concrete deck due to mechanical loading. Two types of simulated cracks, namely, cracks perpendicular and cracks parallel to axis of bea...

Because of the importance of damage detection in manufacturing systems and other areas, many fault detection methods have been developed that are based on a vibration signal. Little work, however, has been reported in the literature on using a recurrence plot method to analyze the vibration signal for damage detection. In this paper, we develop a recurrence plot based fault detection method by ...

The nondestructive evaluation (NDE) of complex composite structures often requires labor intensive, expensive methods due to multiple failure modes, difficulty detecting damage, and the large scale of the structures. Conventional NDE methods have been successful but can be improved by incorporating ideas from other fields. In this work, the technology developed in the infrared camera industry i...