scholarly journals WAVES INDUCED BY NON-PERMANENT PADDLE MOVEMENTS

1972 ◽  
Vol 1 (13) ◽  
pp. 35 ◽  
Author(s):  
C. Campos Moraes ◽  
F. Silveira Ramos ◽  
M. Mendes De Carvalho
Keyword(s):  
Experimental Study ◽  
Gain Function ◽  
Surface Motion ◽  
Irregular Wave ◽  
Input And Output ◽  
Wave Maker

In a flume equipped with an irregular wave maker the motion of the paddle and the resulting waves may be thought of respectively as input and output of a system which, if linear, is for some purposes described by the so-called gain function. A theoretical and experimental study of this function is carried out ma king use of paddle movements that produce transient surface motion.

Experimental study for characteristics of slamming loads on bow of a ship-type FPSO under breaking and irregular wave conditions

2021 ◽  
Vol 224 ◽  
pp. 108738
Author(s):  
Yoon-Jin Ha ◽  
Kyong-Hwan Kim ◽  
Bo Woo Nam ◽  
Sa Young Hong ◽  
Hyunjoe Kim
Keyword(s):  
Experimental Study ◽  
Irregular Wave ◽  
Wave Conditions

Learning vocabulary in spoken input- and output-based tasks

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Phuong Thao Duong ◽  
Maribel Montero Perez ◽  
Piet Desmet ◽  
Elke Peters
Keyword(s):  
Experimental Study ◽  
Comparison Group ◽  
Vocabulary Knowledge ◽  
Learning Gains ◽  
Differential Effects ◽  
Input And Output ◽  
Oral Form ◽  
Experimental Group ◽  
Subsequent Task

Abstract This experimental study explores the differential effects of spoken input-based and output-based tasks on vocabulary knowledge. The study also investigates whether such tasks result in more learning gains than exposure to input-only (no subsequent task). The study employed a pretest-posttest design with two groups: an experimental group (n = 32) who completed both input- and output-based tasks in a counterbalanced way and a comparison group (n = 12) who were only exposed to L2 input. Vocabulary gains were measured at three levels of sensitivity: oral spontaneous use, oral form recall and meaning recall. The findings showed that participants who were only exposed to L2 input learned significantly fewer words than participants who completed the input-based and output-based tasks. No difference in learning gains was found between the input-based and output-based tasks.

EXPERIMENTAL STUDY OF IMMERSED PLATES USED AS BREAKWATERS

1988 ◽  
Vol 1 (21) ◽  
pp. 168
Author(s):  
Alain Drouin ◽  
Yvon Ouellet
Keyword(s):  
Experimental Study ◽  
Volume Of Fluid ◽  
Irregular Wave ◽  
Wave Flume ◽  
Water Wall ◽  
Harmonic Frequencies ◽  
Hydraulic Conditions ◽  
Wave Trains ◽  
Wave Conditions

Under certain wave conditions, an immersed plate which is free to move horizontally produces what has already been called the oscillating water wall phenomenon. When this happens, the plate and the volume of fluid located under the plate move back and forth and then behave as a wave reflector. This type of breakwater was studied in a wave flume with monochromatic and irregular wave trains. Tests have provided a better understanding of the influence of certain parameters that define a plate and the hydraulic conditions under which the plate is used. Results show some interesting efficiencies and also transfert of the energy to harmonic frequencies.

An experimental study of irregular wave forces on multiple quasi-ellipse caissons

2014 ◽  
Vol 13 (3) ◽  
pp. 265-273
Author(s):  
Xiaozhong Ren ◽  
Peng Zhang ◽  
Yuxiang Ma ◽  
Yufan Meng
Keyword(s):  
Experimental Study ◽  
Wave Forces ◽  
Irregular Wave

scholarly journals Differential Effects of Input-based and Output-based Tasks on L2 Vocabulary Learning

2021 ◽  
Vol 24 (3) ◽  
pp. 120-144
Author(s):  
Phuong-Thao Duong ◽  
Maribel Montero Perez ◽  
Piet Desmet ◽  
Elke Peters
Keyword(s):  
Experimental Study ◽  
Vocabulary Learning ◽  
Online Learning Environment ◽  
Differential Effects ◽  
Input And Output ◽  
Quasi Experimental ◽  
Four Levels ◽  
L2 Vocabulary ◽  
Experimental Group ◽  
Recall Level

This paper reports on a quasi-experimental study that explored the differential effects of input- and output-based tasks on L2 vocabulary learning. The study adopted a pretest- posttest within-participants design, with sixty Vietnamese EFL university students. Participants in the experimental group completed four input and four output tasks in an online learning environment. The target items (ten single words and ten compounds) were counterbalanced across the tasks. The study measured vocabulary gains at four levels of sensitivity: spontaneous use of the target items, form recall, meaning recall and meaning recognition. The analyses showed that the input-based tasks resulted in higher vocabulary gains at the meaning recall level, whereas the output-based tasks resulted in better scores at the form recall level. No difference was found in the spontaneous use and meaning recognition tests.

A Wave Maker With Active Reflected Wave Compensation System

2002 ◽  
Author(s):  
Fa´bio Nascimento ◽  
Carlos Levi ◽  
Antonio C. Fernandes ◽  
Paulo de Tarso Esperanc¸a ◽  
Paulo Sergio Gomes
Keyword(s):  
Control System ◽  
Real Time ◽  
Critical Issue ◽  
Compensation System ◽  
Irregular Waves ◽  
Real Time Control ◽  
Incoming Wave ◽  
Reflected Waves ◽  
Irregular Wave ◽  
Wave Maker

Important aspects in the studies to assess the dynamic behavior of ocean vessels or structures, like ships or offshore oil platforms is the capability of generating gravity waves under strict laboratory control. Model test techniques are continuously improving and are very much dependent on the good quality waves that could be generated in a basin. Since ocean basins have finite dimensions, the waves reflected by the models, walls and even to some extent by the beaches, may become a critical issue if you need to guarantee accuracy and reliability for the tests. Besides the undesirable pattern of reflected waves within the test area of the basin, these waves come back onto the wave maker, affecting the correct properties of the wave to be generated. Modern wave generator apparatuses are now being equipped with real time control systems that enable them to generate an irregular wave pattern. At the same time they correct their flap motions to compensate re-reflection of waves from the wave-boards. The quality of such a system depends very much on the efficiency of the algorithm to be implemented in it. This paper discusses the development of an effective mathematical model of a control system used in an irregular wave maker–hinged flap type, featuring active wave reflection compensation. An efficient real time algorithm has been selected to run the control system device. The system is able to generate first order irregular waves and detect reflected waves that approach the wave maker by means of wave probes mounted on the face of the flap. The probe registers the input data to be used by the actuator to compensate the incoming wave by controlling the flap motion. Computer simulations obtained for a wave-maker in a flume are used to demonstrate the efficiency of each step of the theory and the overall accuracy of the compensation system.

THE ROLES OF MODIFIED INPUT AND OUTPUT IN THE INCIDENTAL ACQUISITION OF WORD MEANINGS

1999 ◽  
Vol 21 (2) ◽  
pp. 285-301 ◽  
Author(s):  
Rod Ellis ◽  
Xien He
Keyword(s):  
Experimental Study ◽  
Language Production ◽  
Vocabulary Acquisition ◽  
Word Meanings ◽  
Differential Effects ◽  
New Words ◽  
Input And Output ◽  
Dialogic Interaction

This article reports an experimental study of the differential effects of premodified input, interactionally modified input, and modified output on the comprehension of directions in a listen-and-do task and the acquisition of new words embedded in the directions. The modified output group achieved higher comprehension and vocabulary acquisition scores than either of the input groups. There was no difference between the premodified and interactionally modified input groups. The advantage of the modified output group is explained in terms of the qualitatively superior dialogic interaction that occurred in this condition rather than in terms of actual language production.

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