A rigorous theoretical model of guided waves excitation in a plane dielectric layer under electromagnetic diffraction by a conducting strip

Quantitative ultrasound has shown a significant promise in the assessment of bone characteristics in the recent reports. However, our understanding of wave interaction with bone tissues is still far from complete since the propagation of ultrasonic waves in bones is a very challenging topic due to their multilayer nature. The aim of the current study is to develop a theoretical model for guided waves in a bone-mimicking plate coupled with two soft-tissue layers. Here, the bone plate is modeled as an isotropic solid layer while the soft tissues are modeled as fluid layers. Based on the boundary conditions set for the three-layered structure, a characteristic equation is obtained which results in dispersion curves of the phase and group velocities. New expressions for free guided waves propagating in the trilayered plate are introduced. The amplitudes of wave modes generated by time-harmonic loads applied in the plate are theoretically computed by reciprocity consideration. As an example of calculation, the normalized amplitudes of the lowest wave modes are presented. The obtained results and equations discussed in this study could be, in general, useful for further applications in the area of bone quantitative ultrasound.

Download Full-text

Echo pattern width of a conducting strip loaded with a lossy dielectric layer

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-2003-287 ◽

2003 ◽

Vol 18 (4) ◽

pp. 177-185 ◽

Cited By ~ 1

Author(s):

A.-K. Hamid ◽

M.I. Hussein

Keyword(s):

Dielectric Layer ◽

Lossy Dielectric ◽

Conducting Strip ◽

Pattern Width

Download Full-text

A theoretical model for understanding dentists' behavior in treating patients with AIDS

Journal of Dental Education ◽

10.1002/j.0022-0337.1991.55.11.tb02589.x ◽

1991 ◽

Vol 55 (11) ◽

pp. 708-716 ◽

Cited By ~ 1

Author(s):

MS Chen

Keyword(s):

Theoretical Model

Download Full-text

Experimental and Computational Investigation of Guided Waves in a Human Skull

Ultrasound in Medicine & Biology ◽

10.1016/j.ultrasmedbio.2020.11.019 ◽

2020 ◽

Author(s):

Christopher Sugino ◽

Massimo Ruzzene ◽

Alper Erturk

Keyword(s):

Guided Waves ◽

Computational Investigation ◽

Human Skull

Download Full-text

A Model for Analyzing Suicide Prevention

Crisis ◽

10.1027//0227-5910.21.2.80 ◽

2000 ◽

Vol 21 (2) ◽

pp. 80-89 ◽

Cited By ~ 3

Author(s):

Maila Upanne

Keyword(s):

Risk Factors ◽

Theoretical Model ◽

Protective Factors ◽

Suicide Prevention ◽

Suicide Risk ◽

Practical Work ◽

Individual Risk ◽

Self Assessment ◽

Prevention Project ◽

Individual Risk Factors

This study monitored the evolution of psychologists' (n = 31) conceptions of suicide prevention over the 9-year course of the National Suicide Prevention Project in Finland and assessed the feasibility of the theoretical model for analyzing suicide prevention developed in earlier studies [ Upanne, 1999a , b ]. The study was formulated as a retrospective self-assessment where participants compared their earlier descriptions of suicide prevention with their current views. The changes in conceptions were analyzed and interpreted using both the model and the explanations given by the subjects themselves. The analysis proved the model to be a useful framework for revealing the essential features of prevention. The results showed that the freely-formulated ideas on prevention were more comprehensive than those evolved in practical work. Compared to the earlier findings, the conceptions among the group had shifted toward emphasizing a curative approach and the significance of individual risk factors. In particular, greater priority was focused on the acute suicide risk phase as a preventive target. Nonetheless, the overall structure of prevention ideology remained comprehensive and multifactorial, stressing multistage influencing. Promotive aims (protective factors) also remained part of the prevention paradigm. Practical working experiences enhanced the psychologists' sense of the difficulties of suicide prevention as well as their criticism and feeling of powerlessness.

Download Full-text