This study examined subject-auxiliary inversion errors in wh-questions produced by 88 Korean EFL elementary learners, focusing on whether types of wh-words and auxiliaries could affect inversion acquisition and whether explicit instruction on movement rules could facilitate this process. Guided writing tasks were used as a pretest and a posttest to analyze influence of wh-words and auxiliaries on learners’ inversion in the pretest and effects of instruction on movement rules in the posttest. Results showed that both whwords and auxiliaries significantly influenced learners’ inversion acquisition. Learners struggled more with why-questions than with what-questions, which were selected as representatives of adjunct and argument wh-questions, respectively. More inversion errors occurred in wh-questions requiring do-support than in those involving auxiliary be or modal will, although no significant difference was found between be and will. Experimental lessons with brief explicit instruction on auxiliary movement during regular classes significantly improved learners’ inversion accuracy, particularly in dosupport questions, which posed the greatest challenge in the pretest.
A theoretical model has been studied to describe the sound radiation analysis for structure vibration noise of tire under the action of random moving line forces. When a tire is analyzed, it had been modeled as curved beams with distributed springs and dashpots that represent the radial, tangential stiffness and damping of tire, respectively. The reaction due to fluid loading on the vibratory response of the curved beam is taken into account. The curved beam is assumed to occupy the plane y=0 and to be axially infinite. The curved beam material and elastic foundation are assumed to be lossless Bernoulli-Euler beam theory including a tension force(T), damping coefficient (C) and stiffness of foundation(κ2) will be employed. The expression for sound power is integrated numerically and the results examined as a function of Mach number(M), wave-number ratio(γ) and stiffness factor(ψ). The experimental investigation for structure vibration noise of vehicle tire under the action of random moving line forces has been made. Based on the STSF(Spatial Transformation of Sound Field) techniques, the sound power and sound radiation are measured. Results strongly suggest that operation condition in the tire material properties and design factors of the tire govern the sound power and sound radiation characteristics.
We study data mining technique in an electronic commerce. Customers travel web pages in an shopping mall and they sometimes purchase products. It is important for a web master in a shopping mall to know customer's purchasing patterns. We discover both association rules among customer's purchasing products and customer's traversal paths. We propose three phase mining technique to explore it. In the first phase, it find large items from sales database. In the second phase, it add to traversal paths. In the third phase, it discover associations rules from large items.