Space Time
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Recent papers in Space Time
A theme that has come to the fore in advanced planning for long-range space exploration is the concept of "propellantless propulsion" or "field propulsion." One version of this concept involves the projected... more
To resolve some unphysical interpretations related to velocity measurements by static observers, we discuss the use of generalized observer sets, give a prescription for defining the speed of test particles relative to these observers,... more
Orthogonal frequency division multiplexing (OFDM) is a famous technique for high information rate remote transmission. OFDM might be joined with antenna arrays at the transmitter and recipient to expand the differences pick up and/or to... more
We consider the problems of conflict detection and resolution in air traffic management (ATM) from the perspective of computational geometry and give algo-rithms for solving these problems efficiently. For con-flict resolution, we propose... more
Nonlinear regression is a useful statistical tool, relating observed data and a nonlinear function of unknown parameters. When the parameter-dependent nonlinear function is computationally intensive, a straightforward regression analysis... more
We study a string theory which is exclusively based on extrinsic curvature action. It is a tensionless string theory because the action reduces to perimeter for the flat Wilson loop. We are able to solve and quantize this high-derivative... more
We present the cosmic organism theory in which all visible and invisible matter has different cosmic genetic expressions. The cosmic gene includes codes for the object structure and the space structure. The cosmic digital code for the... more
A fluid-structure-interaction problem comprising a membrane interacting with an aerodynamic flow is of interest for research focused on the behavior of flexible aerospace structures. However, there are no systematic studies available in... more
We present an exact solution of Einstein's field equations in toroidal coordinates. The solution has three regions: an interior with a string equation of state; an Israel boundary layer; and an exterior with constant isotropic pressure... more
According to a previous conjecture, spatial and temporal Lyapunov exponents of chaotic extended systems can be obtained from derivatives of a suitable function, the entropy potential. The validity and the consequences of this hypothesis... more
Studies on denudation rates can provide insight into the influence of climate change, tectonics, and human activities on landscape evolution. Research performed in Central Italy has shown considerable spatial variability of denudation... more
A law of variation for Hubble’s parameter in evolutionary models, that yields a constant value for the deceleration parameter, is presented. It leads naturally to the exclusion of open universes. Si presenta una legge di variazione per il... more
The hydrogenation of maleic acid was investigated using a bimetallic RuRe/C catalyst powder in a semi-batch stirred slurry reactor with the main objective of developing a kinetic model that would provide reliable predictions of the... more