Electromagnetic transmission system

The new geosteering system offers measurements at the bit (below the mud motor) of inclination, rpm, azimuthal gamma ray, azimuthal resistivity, and bit resistivity as seen in Figure 4-298. The signals are transmitted electromagnetically to the MWD sub located above the mud motor, then relayed to surface with the standard mud pressure transmission system. To summarize, the following is recorded Just above the drill bit ... 

Today fiber-optic transmission systems offer several advantages over conventional copper wire and coaxial cable systems. Among these are increased bandwidth, smaller size, lower weight, lack of crosstalk, and a very low susceptibility to electromagnetic interference. It is to be expected that these advantages will open widespread application of fiber-optic transmission systems in the future. This seems to be supported by the fact that a great number of public and in-house trial systems are under test all over the world. 

Lightning overvoltages in overhead power transmission systems are mainly caused by back flashovers (BFOs) of tower insulations. The electromagnetic field around a transmission tower when it is hit by lightning changes dynamically, while electromagnetic waves make several round trips between the shield wire and the ground. 

Fig. 2. Lens system used in transmission-type electron microscope. (left I optical convex lens t, Right) electromagnetic lens...

Interesting phenomena can take place in systems with Fermi resonance under the influence of an external electromagnetic field. Here we consider one example of such behavior - bistable energy transmission through the interface with the Fermi resonance interaction (14). To make the calculations easier, we shall consider the following simplified model. Let a monomolecular layer of a molecules be deposited on the plane surface of a crystal made of b molecules. For the ID case such a system is shown in Fig. 9.7. 

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