abstracttask-based language teaching is considered an effective way to achieve a harmony between grammar and communication. the present study investigates two different ways of teaching modal verbs: task-based versus traditional approaches. to this purpose, an oxford placement test was administered to select 40 homogeneous participants out of a larger population who took this test. the selected...

Abstract Task-based language teaching is considered an effective way to achieve a harmony between grammar and communication. The present study investigates two different ways of teaching modal verbs: task-based versus traditional approaches. To this purpose, an Oxford Placement Test was administered to select 40 homogeneous participants out of a larger population who took this test. The selecte...

Analysis of an aeroelastic bridge system consisting of the fundamental vertical and torsional modes of vibration offers an expeditious assessment of bridge flutter performance. It also produces valuable insight into the multimode coupled bridge response to strong winds. This paper presents closed-form formulations for estimating the modal frequencies, damping ratios, and coupled motions of the ...

The research described in this paper focuses on the application of modal strain techniques on a multi-girder bridge superstructure with the objectives of identifying the presence of damage and detecting false damage diagnosis for such structures. The case study is a one-third scale model of a slab-on-girder composite bridge superstructure, comprised of a steel-free concrete deck with FRP rebars...

This paper presents a modal-expansion analysis of the electromagnetically coupled coaxial dipole antenna. The analysis of the antenna problem is initially simplified using the even-odd mode excitation and then the resultant half structure is divided into two parts; one is the characterization of a coaxial feeding network and the other is the modeling of a sleeve monopole antenna driven by a coa...

The main purpose of this paper is concerned with the sensitivity analysis of main rotor dynamic response pertaining to variation of some relevant system parameters effectively supports the preliminary design of both articulated and hingeless helicopter rotor configurations. The methodology is laid out based on Galerkin solution of partial differential equation (PDE) of main rotor with flexible ...

We utilize a novel coupled-waves approach to design and analyze various types of annular resonators based on Bragg and photonic crystal reflectors. Optimal grating profiles and their corresponding modal fields are found for specific cases such as disk and defect mode (ring) resonators. An excellent match is found between our analytic approximations and exact results obtained by the transfer mat...

The researcher measured the least number of frequency response functions required for the identification of modal parameters, in order to simplify the identification of modal properties of such systems. In this work, the orbital machines are supposed to be a combination of orbital and non-orbital components. Structural Approach specified the identification of dynamic properties only to those ph...

Modal active control enables modifications of the damping and the frequencies of the different resonances of a system. A self-sustained oscillating wind instrument is modelled as a disturbance coupled to a resonator through a non-linear coupling. The aim of this study is to present simulations of modal active control applied to a modeled simplified self-sustained oscillating wind instrument (e....