Adopting the empirical CODE orbit model to Galileo satellites

Most Mexican-Americans do not meet current physical activity recommendations. This paper uses the ORBIT model of obesity intervention development as a framework to outline the process of establishing three employer-based walking challenges in El Paso, Texas, a predominantly Mexican American community. The walking challenges were planned and implemented through the Border Coalition for Fitness and participating partnering organizations. Over 2000 participants and several employers took part in the walking challenges. Results from this ORBIT Phase 1 design intervention suggest that walking challenges are a feasible approach to increase physical activity in Mexican-Americans.

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Daily ambient air mean NO2 concentration modeling and forecasting based on the elliptic-orbit model with weekly quasi-periodic extension: a case study

Stochastic Environmental Research and Risk Assessment ◽

10.1007/s00477-014-0895-2 ◽

2014 ◽

Vol 29 (2) ◽

pp. 547-561 ◽

Cited By ~ 2

Author(s):

Zong-chang Yang

Keyword(s):

Ambient Air ◽

Elliptic Orbit ◽

Modeling And Forecasting ◽

Elliptic Orbit Model ◽

Orbit Model

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Make a Halley’s Comet orbit model

The Physics Teacher ◽

10.1119/1.2341890 ◽

1985 ◽

Vol 23 (8) ◽

pp. 490-491

Author(s):

Francis Podmore ◽

Richard W. Fleet

Keyword(s):

Halley's Comet ◽

Orbit Model ◽

Comet Orbit

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γ DOR: A PULSATING COMPONENT OF KIC 8043961 IN A STELLAR TRIPLE SYSTEM

Revista Mexicana de Astronomía y Astrofísica ◽

10.22201/ia.01851101p.2020.56.02.01 ◽

2020 ◽

Vol 56 (2) ◽

pp. 179-191

Author(s):

C. Kamil ◽

H. A. Dal ◽

O. Özdarcan ◽

E. Yoldaş

Keyword(s):

Major Axis ◽

Primary Component ◽

Mass Ratio ◽

Third Body ◽

Semi Major Axis ◽

Orbital Inclination ◽

The Third ◽

New Findings ◽

Effective Temperatures ◽

Orbit Model

We present new findings about KIC 8043961. We find the effective temperatures of the components as 6900 ± 200 K for the primary, and 6598 ± 200 K for the secondary, while the logarithm of the surface gravities are found to be 4.06 cm s-2 and 3.77 cm s-2, respectively. Combination of the light curve with the spectroscopic orbit model results leads to a mass ratio of 1.09 ± 0.07 with an orbital inclination of 73.71 ± 0.14 and a semi-major axis of 8.05 ± 0.22 R⨀ . Masses of the primary and secondary components are calculated as 1.379 ± 0.109 M⨀ and 1.513 ± 0.181 M⨀, while the radii are found to be 1.806 ± 0.084 R⨀ and 2.611 ± 0.059 R⨀. In addition, we obtain a considerable light contribution (≈0.54%) of a third body. We compute a possible mass for the third body as 0.778 ± 0.002 M⨀. We find that the primary component exhibits γ Dor type pulsations with 137 frequencies.

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Investigations on the Rotordynamic Characteristics of a Hole-Pattern Seal Using Transient CFD and Periodic Circular Orbit Model

Journal of Vibration and Acoustics ◽

10.1115/1.4003403 ◽

2011 ◽

Vol 133 (4) ◽

Cited By ~ 29

Author(s):

Xin Yan ◽

Jun Li ◽

Zhenping Feng

Keyword(s):

Circular Orbit ◽

Flow Analysis ◽

Three Dimensional ◽

Flow Characteristics ◽

Numerical Approach ◽

Deformation Method ◽

Rotordynamic Coefficients ◽

Forward Orbit ◽

Reaction Forces ◽

Orbit Model

Numerical investigations on the rotordynamic characteristics of a typical hole-pattern seal using transient three-dimensional Reynolds-averaged Navier–Stokes (RANS) solution and the periodic circular orbit model were conducted in this work. The unsteady solutions combined with mesh deformation method were utilized to solve the three-dimensional RANS equations and obtain the transient reaction forces on a typical hole-pattern seal rotor at five different excitation frequencies. The relation between the periodic reaction forces and frequency dependent rotordynamic coefficients of the hole-pattern seal was obtained by considering the rotor with a periodic circular orbit (including forward orbit and backward orbit) of the seal center. The rotordynamic coefficients of the hole-pattern seal were then solved based on the obtained unsteady reaction forces and presented numerical method. Compared with the experimental data, the predicted rotordynamic coefficients of the hole-pattern seal are more agreeable with the experiment than that of the ISO-temperature (ISOT) bulk flow analysis and numerical approach with one-direction-shaking model. Furthermore, the unsteady leakage flow characteristics in the hole-pattern seal were also illustrated and discussed in detail.

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Waiting to make an impact: a probable excess of near-Earth asteroids in 2018 LA-like orbits

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834313 ◽

2019 ◽

Vol 621 ◽

pp. A137

Author(s):

C. de la Fuente Marcos ◽

R. de la Fuente Marcos

Keyword(s):

Outer Space ◽

Statistical Significance ◽

Randomization Test ◽

Orbital Evolution ◽

Parent Body ◽

Meteor Shower ◽

Physical Relationship ◽

Common Precursor ◽

Near Earth Asteroids ◽

Orbit Model

Context. The discovery and tracking of 2018 LA marks only the third instance in history that the parent body of a fireball has been identified before its eventual disintegration in our atmosphere. The subsequent recovery of meteorites from 2018 LA was only the second time materials from outer space that reached the ground could be linked with certitude to a particular minor body. However, meteoroids like 2018 LA and its forerunners, 2008 TC3 and 2014 AA, are perhaps fragments of larger members of the near-Earth object (NEO) population. As the processes leading to the production of such fragments are unlikely to spawn just one meteoroid per event, it is important to identify putative siblings and plausible candidates from which the observed meteoroids might have originated. Aims. Here, we study the pre-impact orbital evolution of 2018 LA to place this meteoroid within the dynamical context of other NEOs that follow similar trajectories. Methods. Our statistical analyses are based on the results of direct N-body calculations that use the latest orbit determinations and include perturbations by the eight major planets, the Moon, the barycentre of the Pluto–Charon system, and the three largest asteroids. A state-of-the-art NEO orbit model was used to interpret our findings and a randomization test was applied to estimate their statistical significance. Results. We find a statistically significant excess of NEOs in 2018 LA-like orbits; among these objects, we find one impactor, 2018 LA, and the fourth closest known passer-by, 2018 UA. A possible connection with the χ-Scorpiids meteor shower is also discussed. The largest known NEO with an orbit similar to that of 2018 LA is the potentially hazardous asteroid (454100) 2013 BO73 and we speculate that they both originate from a common precursor via a collisional cascade. Conclusions. Future spectroscopic observations of 454100 and other NEOs in similar orbits may confirm or deny a possible physical relationship with 2018 LA.

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Nonlinear theory of a whistler wave

Journal of Plasma Physics ◽

10.1017/s0022377800009818 ◽

1975 ◽

Vol 14 (3) ◽

pp. 543-549 ◽

Cited By ~ 5

Author(s):

Takashi Yamamoto

Keyword(s):

Growth Rate ◽

Pitch Angle ◽

Particle Distribution ◽

Whistler Wave ◽

Finite Width ◽

Whistler Mode ◽

Mode Spectrum ◽

Numerical Result ◽

Orbit Model ◽

Resonance Function

Using the Dupree—Weinstock perturbed-orbit model of plasma turbulence, we obtain the diffusion equation describing the evolution of the average one-particle distribution function for whistler mode turbulence. The numerical result for electron pitch-angle diffusion within this scheme leads us to conclude that the effect of the resonance broadening due to perturbed orbits on the pitch-angle diffusion coefficient is not large compared with that evaluated by the unperturbed orbit in the whistler mode spectrum with a finite width. Based on the explicitly evaluated resonance function, the effects of this broadening on the growth rate for the whistler wave are also discussed.

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