An Application of the Weis-Fogh Mechanism to Ship Propulsion

1987 ◽  
Vol 109 (2) ◽  
pp. 107-113 ◽  
Author(s):  
M. Tsutahara ◽  
T. Kimura
Keyword(s):  
Dynamic Properties ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Hovering Flight ◽  
Propulsive Efficiency ◽  
Ship Propulsion ◽  
Square Channel ◽  
Propulsion Mechanism ◽  
Two Dimensional Model ◽  
Moving Speed

A mechanism of hovering flight of small insects which is called the Weis-Fogh mechanism is applied to ship propulsion. A model of the propulsion mechanism is proposed, which is based on a two-dimensional model of the Weis-Fogh mechanism and consists of one or two wings in a square channel. The dynamic properties of the model are studied experimentally, and the propulsive efficiency obtained is as high as 75 percent. A model ship equipped with this propulsion mechanism was made, and working tests performed. The model ship sailed very smoothly and the moving speed of the wings was small compared with the advancing speed of the ship.

Commitment to pro- versus counter-attitudinal behavior and the dynamics of social representations

2002 ◽  
Vol 61 (1) ◽  
pp. 34-44 ◽  
Author(s):  
Eric Tafani ◽  
Lionel Souchet
Keyword(s):  
Higher Education ◽  
Social Representations ◽  
Cognitive Restructuring ◽  
Social Representation ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Social Actions ◽  
The Social ◽  
Two Dimensional Model ◽  
Students Attitudes

This research uses the counter-attitudinal essay paradigm ( Janis & King, 1954 ) to test the effects of social actions on social representations. Thus, students wrote either a pro- or a counter-attitudinal essay on Higher Education. Three forms of counter-attitudinal essays were manipulated countering respectively a) students’ attitudes towards higher education; b) peripheral beliefs or c) central beliefs associated with this representation object. After writing the essay, students expressed their attitudes towards higher education and evaluated different beliefs associated with it. The structural status of these beliefs was also assessed by a “calling into question” test ( Flament, 1994a ). Results show that behavior challenging either an attitude or peripheral beliefs induces a rationalization process, giving rise to minor modifications of the representational field. These modifications are only on the social evaluative dimension of the social representation. On the other hand, when the behavior challenges central beliefs, the same rationalization process induces a cognitive restructuring of the representational field, i.e., a structural change in the representation. These results and their implications for the experimental study of representational dynamics are discussed with regard to the two-dimensional model of social representations ( Moliner, 1994 ) and rationalization theory ( Beauvois & Joule, 1996 ).

Pulse Antennas: Accurate Solution of Two-Dimensional Model Problems for Structures with Gratings as Dispersive Elements

2001 ◽  
Vol 55 (8) ◽  
pp. 14
Author(s):  
A. I. Vyazmitinova ◽  
V. L. Pazynin ◽  
Andrei Olegovich Perov ◽  
Yurii Konstantinovich Sirenko ◽  
H. Akdogan ◽  
...  
Keyword(s):  
Accurate Solution ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Two Dimensional Model

Consolidation and Shearing Tests by Two-Dimensional Model Powder Particles

1969 ◽  
Vol 18 (189) ◽  
pp. 489-493
Author(s):  
Kaoru UMEYA ◽  
Nobuyuki KITAMOIR ◽  
Ryuichi HARA ◽  
Tatsuo YOSHIDA
Keyword(s):  
Two Dimensional ◽  
Dimensional Model ◽  
Two Dimensional Model ◽  
Powder Particles
Sign in / Sign up

Export Citation Format

Share Document