GPS based prediction of the instantaneous impact point for sounding rockets

The scanning electron microscope (SEM) builds up an image by sampling contiguous sub-volumes near the surface of the specimen. A fine electron beam selectively excites each sub-volume and then the intensity of some resulting signal is measured. The spatial resolution of images made using such a process is limited by at least three factors. Two of these determine the size of the interaction volume: the size of the electron probe and the extent to which detectable signal is excited from locations remote from the beam impact point. A third limitation emerges from the fact that the probing beam is composed of a finite number of discrete particles and therefore that the accuracy with which any detectable signal can be measured is limited by Poisson statistics applied to this number (or to the number of events actually detected if this is smaller).

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Effects of Impact Point on Ball Movement During Putting Stroke in Golf

Korean Journal of Sports Science ◽

10.35159/kjss.2020.08.29.4.1105 ◽

2020 ◽

Vol 29 (4) ◽

pp. 1105-1111

Author(s):

Jong-In Kim

Keyword(s):

Impact Point

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Conceptual Design of a Recovery System for Sounding Rockets Using Magnus Effect

AIAA Scitech 2020 Forum ◽

10.2514/6.2020-0061 ◽

2020 ◽

Author(s):

Ahmed Osama ◽

Mahmoud Y. Ahmed

Keyword(s):

Conceptual Design ◽

Sounding Rockets ◽

Magnus Effect ◽

Recovery System

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Influence of the Submerged Entry Nozzle’s Bottom Well on the Characteristics of Its Exit Jets

Metals ◽

10.3390/met11030398 ◽

2021 ◽

Vol 11 (3) ◽

pp. 398

Author(s):

Jesus Gonzalez-Trejo ◽

Cesar A. Real-Ramirez ◽

Jose Raul Miranda-Tello ◽

Ruslan Gabbasov ◽

Ignacio Carvajal-Mariscal ◽

...

Keyword(s):

Continuous Casting ◽

Liquid Steel ◽

Mold Wall ◽

Casting Machine ◽

Submerged Entry Nozzle ◽

Central Plane ◽

Impact Point ◽

Single Vortex ◽

Hydrodynamic Analysis ◽

Principal Characteristics

In vertical continuous casting machines the liquid steel from the tundish is poured into the mold through the Submerged Entry Nozzle (SEN). The shape and direction of the SEN exit jets affect the liquid steel dynamics inside the mold. This work quantifies the effect of the SEN pool on the principal characteristics of the jets emerging from it, precisely, the shape, the spread angles, and the mold impact point. Experimental and numerical simulations were carried out using a SEN simplified model, a square-shaped bore nozzle with square-shaped outlet ports whose length is minimal. These experiments showed two well-defined behaviors. When a single vortex dominates the hydrodynamics inside the simplified SEN, the exit jets spread out and are misaligned about the mold’s central plane. On the contrary, when the inner flow pattern shows two vortexes, the exit jets are compact and parallel to the mold wide walls. The measured difference on the jet’s falling angles is 5°, approximately, which implies that in an actual casting machine, the impingement point at the narrow mold wall would have a variation of 0.150 m. This hydrodynamic analysis would help design new SENs for continuous casting machines that improve steel quality.

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