Resonance suppressed magnetic probe for measuring electromagnetic field intensity

Author(s):  
Jung-Min Kim ◽  
Woo-Young Song ◽  
Jong-Gwan Yook
2012 ◽  
Vol 12 (3&4) ◽  
pp. 231-252
Author(s):  
Luis Octavio Castanos

We consider two two-level atoms fixed at different positions, driven by a resonant monochromatic laser field, and interacting collectively with the quantum electromagnetic field. A Born-Markov-secular master equation is used to describe the dynamics of the two atoms and the steady-state is obtained analytically for a configuration of the atoms. The steady-state populations of the energy levels of the free atoms, entanglement, quantum and geometric discords and degree of mixedness are calculated analytically as a function of the laser field intensity and the distance between the two atoms. It is found that there is a possibility of considerable steady-state entanglement and left/right quantum discord and that these can be controlled either by increasing/decreasing the intensity of the laser field or by increasing/decreasing the distance between atoms. It is shown that the system of two atoms can be prepared in a separable mixed state with non-zero quantum discord that turns into an $X$-state for high laser field intensities. The behavior and relationships between the different correlations are studied and several limiting cases are investigated.


Author(s):  
Robin Hanson

As we will discuss in Chapter 18 , Cities section, em cities are likely to be big, dense, highly cost-effective concentrations of computer and communication hardware. How might such cities interact with their surroundings? Today, computer and communication hardware is known for being especially temperamental about its environment. Rooms and buildings designed to house such hardware tend to be climate-controlled to ensure stable and low values of temperature, humidity, vibration, dust, and electromagnetic field intensity. Such equipment housing protects it especially well from fire, flood, and security breaches. The simple assumption is that, compared with our cities today, em cities will also be more climate-controlled to ensure stable and low values of temperature, humidity, vibrations, dust, and electromagnetic signals. These controls may in fact become city level utilities. Large sections of cities, and perhaps entire cities, may be covered, perhaps even domed, to control humidity, dust, and vibration, with city utilities working to absorb remaining pollutants. Emissions within cities may also be strictly controlled. However, an em city may contain temperatures, pressures, vibrations, and chemical concentrations that are toxic to ordinary humans. If so, ordinary humans are excluded from most places in em cities for safety reasons. In addition, we will see in Chapter 18 , Transport section, that many em city transport facilities are unlikely to be well matched to the needs of ordinary humans. Higher prices to rent volume near city centers should push such centers to extend both higher into the sky and deeper into the ground, as happens in human cities today. It should also push computers in city centers to be made from denser physical devices, that is, supporting more computing operations per volume, even if such devices are proportionally more expensive than less dense variants. City centers are also less likely to use deterministic computing devices, if such devices require more volume and cooling. It may be possible to make computing devices that use less mass per computing speed supported, even if they cost more per operation computed. Such lighter devices are more likely to be used at higher city elevations, because they reduce the cost of the physical structures needed to hold them at these heights.


2019 ◽  
Vol 11 (5) ◽  
Author(s):  
Stéphane Faure ◽  
Jean-François Bobo ◽  
Daniel Prost ◽  
François Issac ◽  
Julian Carrey

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2604 ◽  
Author(s):  
Lyu ◽  
Liu ◽  
Hu ◽  
Yang ◽  
Huang ◽  
...  

Fabricating an Inconel 718 superalloy using electromagnetic stirring assisted laser solid forming (EMS-LSF) is a novel method to modify its microstructure and mechanical properties by consuming the Nb element in the γ phase to alleviate interdendritic segregation. The precipitate of the δ phase at 950 °C after EMS-LSF can help to achieve the uniform diffusion of Nb, and can also improve its mechanical properties. The precipitation behavior of the δ phase in an EMS-LSF Inconel 718 superalloy with different heat treatment processes has been investigated. The results show that the morphology of the δ phase changes from rod-like to a long-needle shape and tends to grow from the inter dendrite to the core dendrite with electromagnetic field intensity increasing, which is accompanied by the “cutting” and “dissolution” of the Laves phase. Through precipitation kinetics analysis, the precipitation rate of the δ phase is seen to increase with the electromagnetic field intensity increasing. Under a combination of electromagnetic stirring and laser solid forming, the microhardness of the Inconel 718 samples increased slightly due to the fact that a higher content of Nb was distributed in the core dendrite resulting from the serious convection of liquid metal, which can strengthen the matrix.


2004 ◽  
Author(s):  
Maxim V. Bashevoy ◽  
Alexander A. Ezhov ◽  
Sergey A. Magnitskii ◽  
Dmitrii V. Malakhov ◽  
Dmitry A. Muzychenko ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document