Introduction We describe how spoken dialogue interfaces make a simulation-based trainer and an intelligent tutoring system into a powerful package for Naval damage control education. An advanced simulator gives a student real-time experience that would otherwise be extremely costly to provide. The dialogue interface to the simulator uses a simple finite-state script to allow the user to issue o...

A full-scale seven-story reinforced concrete building section/slice was tested on the NEES shake table at the University of California San Diego during the period of October 2005 to January 2006. Three output-only system identification methods were used to extract the modal parameters (natural frequencies, damping ratios, and mode shapes) of the test structure at different damage states. In thi...

engineering ceramics due to high-strength-to-weight ratio, wear and corrosion resistance, and high strength temperatures, in the industries especially in aerospace, automobile, electronics and computers are used widely. in attention to the  increasingly usage process of these material, applying of conventional machining methods  for producing  machined into complex and desired shapes or making ...

in this study, the vibration of cracked plates is investigated using the differential quadrature method and experimental modal analysis. the crack, which is assumed to be open, is modeled by the extended rotational spring. with its finite length, the crack divides the plate into six segments. then, the differential quadrature is applied to the governing differential equations of motion and the ...

Simultaneous learning of multiple functions is one of the fundamental issues not only to design intelligent robots but also to understand human’s cognitive developmental process since we, human, do so in our daily lives but we do not know how to do. Drawing an analogy to the well-known bias in child language development, we propose the mutual exclusivity selection principle (μX principle) for l...

We describe a polarization-selective beam splitter by a sandwiched grating, which can fulfill the high efficiency element for TE polarization and the two-port output for TM polarization. The modal method and the rigorous coupled-wave analysis (RCWA) are employed together to optimize the polarization-selective beam splitter. According to the modal method, the grating duty cycle and period are di...

A time-frequency identification technique based on wavelet transform is formulated and applied to free-decay responses of linear systems with non-proportional viscous damping. The Cauchy mother wavelet is used. Frequencies, modal damping ratios and complex mode shapes are identified from output-only free vibration signals. This identification technique has also shown to be effective when the (n...

A comparative assessment of two time–domain output–only vector structural identification methods, namely a Vector AutoRegressive (VAR) and a stochastic subspace method, is presented via their application to a laboratory cable–stayed bridge structure. A brief overview of the estimation methods is provided, while model order selection and validation are discussed. The modal frequencies and dampin...

Complex structures often include hollow parts. These hollow parts constitute the skeleton of the structure and are largely responsible for its global behavior, hence the importance of analyzing them precisely. The method we propose in this paper is a modal method based on the modal analysis of elements of hollow parts. This method does not require nodal degrees of freedom on the boundaries betw...

In this paper we consider a large class of partial diierential equations (PDEs) with distributed control and with a time-delay in the feedback loop. We analyze the relationship between the poles of the closed-loop transfer function and the exponential modes of the underlying retarded PDE in order to derive internal stability properties from external ones. Our approach is based on a combination ...