Search results for "Gravity"
showing 7 items of 537 documents
Biological and Mechanical Characterization of the Random Positioning Machine (RPM) for Microgravity Simulations
2021
The rapid improvement of space technologies is leading to the continuous increase of space missions that will soon bring humans back to the Moon and, in the coming future, toward longer interplanetary missions such as the one to Mars. The idea of living in space is charming and fascinating; however, the space environment is a harsh place to host human life and exposes the crew to many physical challenges. The absence of gravity experienced in space affects many aspects of human biology and can be reproduced in vitro with the help of microgravity simulators. Simulated microgravity (s-μg) is applied in many fields of research, ranging from cell biology to physics, including cancer biology. In…
Testing and implementing a new approach to estimating interregional output multipliers using input-output data for South Korean regions
2020
Flegg's location quotient (FLQ) is a useful tool for estimating intraregional output multipliers. This paper uses it as one component when estimating interregional multipliers. Using statistical information criteria and official data for 16 South Korean regions, it is found that the best approach is to combine the FLQ with a simple trade model. The paper explains how the proposed procedure can be implemented for both multiple and individual regions, and also how a region-specific value for the unknown parameter δ in the FLQ formula can be determined. Finally, an illustrative case study of one of the regions is carried out.
On the Stability of the Soft Pendulum With Affine Curvature: Open-Loop, Collocated Closed-Loop, and Switching Control
2022
This letter investigates the stability properties of the soft inverted pendulum with affine curvature - a template model for nonlinear control of underactuated soft robots. We look at how changes in physical parameters affect stability and equilibrium. We give conditions under which zero dynamics corresponding to a collocated choice of the output is (locally or globally) stable or unstable. We leverage these results to design a switching controller that stabilizes a class of nonlinear equilibria of the pendulum, which can drive the system from one equilibrium to another.
Regional headquarters and foreign direct investment
2022
Headquarters (HQs) provide a wide range of services, playing a fundamental role in Foreign Direct Investment (FDI). We use the structural gravity equation to investigate the effect of regional HQs on three dimensions of FDI (number of foreign projects, capital investment, and jobs) at the country-pair-sector level. Furthermore, we explore two underlying mechanisms that help explain this relationship: financial constraints and informational costs and uncertainty. We find a positive effect of regional HQs on FDI, as well as intercountry and intersector spillovers. Our results are robust, accounting for HQ intensity, domestic investment, and endogeneity tests.
A Dynamic Analysis of Tourism Determinants in Sicily
2015
This study provides an initial analysis of the key determinants of tourism in Sicily. In doing so, it responds to the general lack of a scientific approach in the study and management of tourism in Sicily. By mixing a gravity approach and system dynamics methodology, the attractiveness of Sicily is examined, taking into account both structural and promotional aspects that might affect tourism demand. The results strongly suggest that the island's natural and cultural resources, the road infrastructure and the urban environment are important determinants of tourism demand in Sicily. The findings may be useful for local authorities involved in the development of tourism, and represent a star…