Analytical and Numerical Studies of Three-Dimensional Trajectories to the Moon

1960 ◽  
Vol 27 (8) ◽  
pp. 561-573 ◽  
Author(s):  
A. B. MICKELWAIT ◽  
R. C. BOOTON
2019 ◽  
Vol 221 ◽  
pp. 01003
Author(s):  
Pavel Radchenko ◽  
Stanislav Batuev ◽  
Andrey Radchenko

The paper presents results of applying approach to simulation of contact surfaces fracture under high velocity interaction of solid bodies. The algorithm of erosion -the algorithm of elements removing, of new surface building and of mass distribution after elements fracture at contact boundaries is consider. The results of coordinated experimental and numerical studies of fracture of materials under impact are given. Authors own finite element computer software program EFES, allowing to simulate a three-dimensional setting behavior of complex structures under dynamic loads, has been used for the calculations.


2018 ◽  
Vol 32 (34n36) ◽  
pp. 1840083 ◽  
Author(s):  
Xuetong Liu ◽  
Jianhua Liu ◽  
Huajiang Ouyang ◽  
Zhenbing Cai ◽  
Jinfang Peng ◽  
...  

The dynamic response of bolted joints subjected to torsional excitation is investigated experimentally and numerically. First, the effects of the initial preload and the angular amplitude on axial force loss of the bolt were studied. Second, the change of hysteresis loops with the increasing number of loading cycles was found under a larger torsional angle. At last, a fine-meshed three-dimensional finite element model was built to simulate the bolted joint under torsional excitation, from which the hysteresis loops were obtained under varying angular amplitudes. The results of numerical analysis are in good agreement with those of experiments.


2018 ◽  
Vol 18 (09) ◽  
pp. 1850107 ◽  
Author(s):  
Yan-An Gao ◽  
Qing-Shan Yang ◽  
Yun Dong

A three-dimensional (3D) pedestrian–structure interaction (PSI) system based on the biomechanical bipedal model is presented for general applications. The pedestrian is modeled by a bipedal mobile system with one lump mass and two compliant legs, which comprise damping and spring elements. The continuous gaits of the pedestrian are maintained by a self-driven walking kinetic energy, which is a new driven mechanism for the mobile unit. This self-driven mechanism enables the pedestrian to operate at a varying total energy level, as an important component for further modeling of the crowd-structure dynamic interaction. Numerical studies show that the pedestrian walking on the structure leads to a reduction in the natural frequency, but an increase in the damping ratio of the structure. This model can also reproduce the reaction forces between the feet and structure, similar to those measured in the field. In addition, the proposed model can well describe the 3D pedestrian–structure dynamic interaction. It is recommended for use in further study of more complicated scenarios such as the dynamic interaction between a large scale kinetic crowd and slender footbridge.


2014 ◽  
Vol 629-630 ◽  
pp. 330-336
Author(s):  
Mohammad Ali Yazdi ◽  
Saeid Motaghi ◽  
Jian Yang

This paper investigates a set of nonlinear numerical studies slab subjected to blast loading. A three-dimensional finite element model is developed using ABAQUS by emphasizing on using concrete with recycled concrete aggregate and crushed clay bricks (RCA and CCB) to promote the strength of slab against blast loading. Different charge weights of 0.2–0.55 kg equivalent weight of TNT at a 0.4 m standoff above the slabs were considered as variables in order to evaluate damage levels and define the relations among these variables with respect to the residual strength of slab after blast. The maximum deflection and spalling ratio of the specimens were verified with the experimental data. The results corroborate that using recycled concrete aggregate and crushed clay bricks improve the strength of slabs against blast loading. In addition, the best fraction of this type of materials has been illustrated.


2008 ◽  
Vol 583 ◽  
pp. 257-275 ◽  
Author(s):  
Ferdinando Auricchio ◽  
Alessandro Reali

The use of shape memory alloys (SMA) in an increasing number of applications in many ¯elds of engineering, such as biomedical engineering, is leading to a growing interest toward an exhaustive modeling of their macroscopic behavior in order to construct reliable simulation tools for SMA devices. In this paper we review a robust three-dimensional model able to reproduce both pseudo-elastic and shape-memory behaviors and we report numerical studies where it is used for the simulation of SMA-based biomedical devices.


Tempo ◽  
1970 ◽  
pp. 2-15
Author(s):  
Stephen Walsh

The Rising of the Moon is Nicholas Maw's second opera, and like its predecessor, One Man Show, it is a comedy. As far as subject matter and its treatment go, however, the resemblance ends there. One Man Show is a farce, based on a flimsy comic idea by Saki. The Rising of the Moon is a romantic comedy whose central situation—though necessarily presented in high theatrical relief—is essentially realistic and depends for its effect on the portrayal of a number of true-to-life three-dimensional characters. Beverley Cross's libretto, based on an entirely original idea, is set in Ireland in the year 1875. This was a tragic period in Irish history. After years of unavailing struggle for home rule and for the emancipation of a Catholic people from minority government by Protestants, Ireland had found herself in the mid-nineteenth century still bound in a most unfavourable union with England. Her economic and industrial growth was deliberately kept down by legislation in Westminster, prompted by fears of competition with home industry. The poverty of most Irish peasants was extreme, as it had been even before the potato famine of the late 1840s, and many were still suffering at the hands of unscrupulous landlords who were quite prepared to implement laws which made eviction the normal penalty for non-payment of rent. In these circumstances the English were naturally both hated and feared. Yet those who tried to stir popular feeling into action—Daniel O'Connell, the Young Irelanders, the Fenians—found their hands tied by Ireland's internal religious and social divisions, and by the listlessness of an underfed, underclothed, even underhoused people. Such revolutionary outbreaks as took place were isolated and poorly organised, and although the English executive in Ireland—including the army—might tend to regard all Irish peasants as potential rebels, they had long since learnt that the rebel bark was a good deal worse than the insurgent bite, and so they treated the natives accordingly.


1997 ◽  
Vol 06 (03) ◽  
pp. 349-360
Author(s):  
Ping Xie ◽  
Jian-Hua Dai ◽  
Peng-Ye Wang ◽  
Hong-Jun Zhang

The gain and the spatial fidelity of signal amplification in photorefractive BaTiO 3: Ce , with considerations of the effect of the externally applied electric field and the fanning effect (or noise), are numerically studied using a three-dimensional analysis. Although the gain of the signal can be enhanced with the applied field, its spatial fidelity is greatly reduced, especially at a small angle between the two propagation directions of the pump and signal beams. The fanning effect reduces the spatial fidelity, and the smaller the input signal to pump intensity ratio is, the smaller the fidelity becomes. At large magnitudes of the applied field, the applied field plays a critical role in the reduction of the fidelity of the signal and the fanning effect on the fidelity is negligible.


2002 ◽  
Vol 35 (31) ◽  
pp. 6517-6543 ◽  
Author(s):  
A Cucchieri ◽  
J Engels ◽  
S Holtmann ◽  
T Mendes ◽  
T Schulze

2015 ◽  
Vol 12 (102) ◽  
pp. 20140715 ◽  
Author(s):  
Amor A. Menezes ◽  
John Cumbers ◽  
John A. Hogan ◽  
Adam P. Arkin

This paper demonstrates the significant utility of deploying non-traditional biological techniques to harness available volatiles and waste resources on manned missions to explore the Moon and Mars. Compared with anticipated non-biological approaches, it is determined that for 916 day Martian missions: 205 days of high-quality methane and oxygen Mars bioproduction with Methanobacterium thermoautotrophicum can reduce the mass of a Martian fuel-manufacture plant by 56%; 496 days of biomass generation with Arthrospira platensis and Arthrospira maxima on Mars can decrease the shipped wet-food mixed-menu mass for a Mars stay and a one-way voyage by 38%; 202 days of Mars polyhydroxybutyrate synthesis with Cupriavidus necator can lower the shipped mass to three-dimensional print a 120 m 3 six-person habitat by 85% and a few days of acetaminophen production with engineered Synechocystis sp. PCC 6803 can completely replenish expired or irradiated stocks of the pharmaceutical, thereby providing independence from unmanned resupply spacecraft that take up to 210 days to arrive. Analogous outcomes are included for lunar missions. Because of the benign assumptions involved, the results provide a glimpse of the intriguing potential of ‘space synthetic biology’, and help focus related efforts for immediate, near-term impact.


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