On the Impossibility of Detecting Uniform Motion

A assessment method on quality detected system was developed on cylinders inner wall coating through the hydraulic radial expansive load system and acoustic emission testing technology,. Put double probes linear position principle and uniform motion of load system together, and make curved positioning come true based on the technical principle of locating acoustic emission source. The disadvantage was solved that double probes can’t make acoustic emission source planar positioning. The result showed that this system can provide a precise identification and location; it has fast testing velocity and portable device.

Download Full-text

Design of the Conjugate Cam Induction Hardening Mechanism and Establishment of the Motion Controlling Mathematical Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.155-156.726 ◽

2012 ◽

Vol 155-156 ◽

pp. 726-730

Author(s):

Zhong Hua Li ◽

Qian Tang ◽

Di Yan ◽

Jie Wu

Keyword(s):

Mathematical Model ◽

Induction Hardening ◽

Uniform Motion ◽

Hardening Mechanism ◽

Kinematic Relationship ◽

Nc Machine ◽

The Common ◽

Relationship Of ◽

The Mathematical Model ◽

Basic Motion

The common methods of cam induction hardening are discussed at present. By analyzing the basic motion law of conjugate cam, a new induction hardening mechanism is designed. The motion controlling mathematical model is built on the basis of the kinematic relationship of the transmission of the induction hardening mechanism. Through the mathematical model calculation, we can get angular velocity of the workbench, then realize that single axis on NC machine controls the inductor to make isometric uniform motion relative to the cam surface, so that the cam hardening depth distribution is uniform.

Download Full-text

VI. On a new astronomical clock, and a pendulum governor for uniform motion

Proceedings of the Royal Society of London ◽

10.1098/rspl.1868.0097 ◽

1869 ◽

Vol 17 ◽

pp. 468-470

Keyword(s):

Uniform Motion ◽

Geometrical Transformation ◽

Astronomical Clock ◽

The Dead ◽

Better Than

It seems strange that the dead-beat escapement should still hold its place in the astronomical clock, when its geometrical transformation, the cylinder escapement of the same inventor, Graham, only survives in Geneva watches of the cheaper class. For better portable time-keepers, it has been altered (through the rack-and-pinion movement) into the detached lever, which has proved much more accurate. If it is possible to make astronomical clocks go better than at present by merely giving them a better escapement, it is quite certain that one on the same principle as the detached lever, or as the ship-chronometer escapement, would improve their time-keeping. But the inaccuracies hitherto tolerated in astronomical clocks may be due more to the faultiness of the mercury compensation pendulum, and of the mode in which it is hung, and of the instability of the supporting clock-case or framework, than to imperfection of the escapement and the greatness of the arc of vibration which it requires ; therefore it would be wrong to expect confidently much improvement in the time-keeping merely from improvement of the escapement. I have therefore endeavoured to improve both the compensation for change of temperature in the pendulum, and the mode of its support, in a clock which I have recently made with an escapement on a new principle, in which the simplicity of the dead-beat escapement of Graham is retained, while its great defect, the stopping of the whole train of wheels by pressure of a tooth upon a surface moving with the pendulum, is remedied.

Download Full-text

Bose-Einstein-type statistics, order statistics and planar random motions with three directions

Advances in Applied Probability ◽

10.1239/aap/1093962242 ◽

2004 ◽

Vol 36 (3) ◽

pp. 937-970 ◽

Cited By ~ 5

Author(s):

S. Leorato ◽

E. Orsingher

Keyword(s):

Partial Differential Equations ◽

Order Statistics ◽

Constant Velocity ◽

Uniform Motion ◽

Change Of Direction ◽

Telegraph Process ◽

Cyclic Motion ◽

Different Types ◽

Random Motions ◽

Bose Einstein

In this paper we study different types of planar random motions (performed with constant velocity) with three directions, defined by the vectors dj = (cos(2πj/3), sin(2πj/3)) for j = 0, 1, 2, changing at Poisson-paced times. We examine the cyclic motion (where the change of direction is deterministic), the completely uniform motion (where at each Poisson event each direction can be taken with probability ) and the symmetrically deviating case (where the particle can choose all directions except that taken before the Poisson event). For each of the above random motions we derive the explicit distribution of the position of the particle, by using an approach based on order statistics. We prove that the densities obtained are solutions of the partial differential equations governing the processes. We are also able to give the explicit distributions on the boundary and, for the case of the symmetrically deviating motion, we can write it as the distribution of a telegraph process. For the symmetrically deviating motion we use a generalization of the Bose-Einstein statistics in order to determine the distribution of the triple (N0, N1, N2) (conditional on N(t) = k, with N0 + N1 + N2 = N(t) + 1, where N(t) is the number of Poisson events in [0, t]), where Nj denotes the number of times the direction dj (j = 0, 1, 2) is taken. Possible extensions to four directions or more are briefly considered.

Download Full-text

A Two-Phase Model of Air Shock Wave Induced by Rock-Fall in Closed Goaf

10.20944/preprints201611.0083.v2 ◽

2017 ◽

Author(s):

Fengyu Ren ◽

Yang Liu ◽

Jianli Cao ◽

Rongxing He ◽

Yuan Xu ◽

...

Keyword(s):

Shock Wave ◽

Theoretical Analysis ◽

Phase Model ◽

Rock Fall ◽

Uniform Motion ◽

Two Phase ◽

Protective Measures ◽

Computational Fluid Dynamics Cfd ◽

Series Of Experiments ◽

Wave Induced

In this paper, a two-phase model of air shock wave induced by rock-fall was described. The model was made up of the uniform motion phase (velocity was close to 0 m·s-1) and the acceleration movement phase. The uniform motion phase was determined by experience, meanwhile the acceleration movement phase was derived by the theoretical analysis. A series of experiments were performed to verify the two-phase model and obtained the law of the uniform motion phase. The acceleration movement phase was taking a larger portion when height of rock-fall was higher with the observations. Experimental results of different falling heights showed good agreements with theoretical analysis values. Computational fluid dynamics (CFD) numerical simulation had been carried out to study the variation velocity with different falling height. As a result of this, the two-phase model could accurately and convenient estimating the velocity of air shock wave induced by rock-fall. The two-phase model could provide a reference and basis for estimating the air shock waves' velocity and designing the protective measures.

Download Full-text