Dynamic analysis of firing mechanism of underwater pistol

Dung Thai Nguyen; Hung Van Nguyen

doi:10.32508/stdj.v20ik2.449

Dynamic analysis of firing mechanism of underwater pistol

Science and Technology Development Journal ◽

10.32508/stdj.v20ik2.449 ◽

2017 ◽

Vol 20 (K2) ◽

pp. 61-65

Author(s):

Dung Thai Nguyen ◽

Hung Van Nguyen

Keyword(s):

Theoretical Model ◽

Dynamic Analysis

The important problem of designing underwater pistol was analysed and calculated the dynamics of firing mechanism. On the basis of analyzing the performance of the underwater pistol, the paper presents a theoretical model for analysing the dynamics of firing mechanism of underwater pistol with the with the resistance of water acting on firing pin and slide. The result of this research can be applied to design the underwater pistol and underwater firearm.

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Dynamic effects of vehicles on tracks in the case of raising train speeds

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1243/0954409011531459 ◽

2001 ◽

Vol 215 (2) ◽

pp. 125-135 ◽

Cited By ~ 57

Author(s):

W. M. Zhai ◽

Q. C. Wang ◽

Z. W. Lu ◽

X. S. Wu

Keyword(s):

Theoretical Model ◽

Dynamic Analysis ◽

Simulation Software ◽

Dynamic Effects ◽

Railway Transportation ◽

Passenger Cars ◽

Speed Range ◽

Coupling Dynamics ◽

Passenger Trains

In order to enhance the efficiency of railway transportation, Chinese Railways has decided to raise the speed of trains on the existing railway main lines. A theoretical model and the corresponding simulation software, VICT, based on the vehicle-track coupling dynamics are employed to analyse dynamic effects of trains on track structures caused by raising train speeds. Chinese passenger cars and freight cars running on the lines where speed has been raised were chosen for investigation. It is shown that raising train speeds on the existing railway lines obviously intensifies the dynamic effects of vehicles on tracks, especially in the turnouts, in the welded rail joints, and in the sections of bridge-subgrade connections. The occurrence of wheel flats becomes more general after raising train speeds. An unfavourable peak of dynamic effects of wheel flats on tracks is observed in the speed range from 140 to 160 km/h, which is just the region of running speeds for passenger trains after the increase in the speed. Some basic countermeasures, including stricter maintenance standards for the speed-raised railways, are proposed to solve these problems, on the basis of dynamic analysis.

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Dynamic Analysis of Rupture in Thin Fluid Films. I—A Noninertial Theory

Journal of Lubrication Technology ◽

10.1115/1.3254555 ◽

1983 ◽

Vol 105 (1) ◽

pp. 96-104 ◽

Cited By ~ 3

Author(s):

C. H. T. Pan

Keyword(s):

Steady State ◽

Theoretical Model ◽

Dynamic Analysis ◽

Squeeze Film ◽

Transient Condition ◽

Film Rupture ◽

Fluid Films ◽

Film Pressure ◽

Sliding Surfaces ◽

Thin Fluid

A noninertial theoretical model for the dynamics of film rupture has been formulated. Under the transient condition, movement of the rupture boundary is governed by the condition of flow continuity between the film flux and adhered film transport in the cavitation domain. The traditional Swift-Stieber condition for film breakup is shown to be valid upon reaching steady-state. Generalization is extended to allow consideration of two sliding surfaces and the pure squeeze-film. The possibility of subcavitation film pressure is shown to result in dry regions in the cavitation domain.

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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

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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.

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