Travelling

Deflagration. In a deflagration, the flame front travels through the flammable mixture relatively slowly, i.e., at subsonic velocity. 

Detonation. In a detonation, the flame front travels as a shock wave, followed closely by a combustion wave, which releases the energy to sustain the shock wave. The detonation front travels with a velocity greater than the speed of sound in the unreacted medium. 

Rf, Rg, Rf A measure of retention of solute in chromatography defined as the ratio of the distance travelled by the solute to the distance travelled by the mobile phase. 

Each reflector contributes a reflection along a raypath to the surface, defined by the normal incidence reflection point (shortest travel time)... 

The formation cuttings that are ohipped off by the bit travel upward with the mud and are caught and analysed at the surface. This provides information about the lithology and qualitative indications of the porosity. 

In the event of a sudden loss of mud In an Interval containing overpressures the mud column in the annulus will drop, thereby reducing the hydrostatic head acting on the formation to the point where formation pressure exceeds mud pressure. Formation fluids (oil, gas or water) can now enter the borehole and travel upwards. In the process the gas will expand considerably but will maintain its initial pressure. The last line of defence leff is the blowout preventer. However, although the BOP will prevent fluid or gas escape to the surface, closing in the well may lead to two potentially disastrous situations ... 

The sonic tool measures the time taken for a sound wave to pass through the formation. Sound waves travel in high density (i.e. low porosity) formation faster than in low density (high porosity) formation. The porosity can be determined by measuring the transit time for the sound wave to travel between a transmitter and receiver, provided the rock matrix and fluid are known. 

A resonance in the layered stracture occurs when echoes between two boundaries travel back and forth due to differences in acoustic impedances at the boundaries. For multi-layer structures a number of resonances can be observed depending on their geometry and condition. For each particular defect-free structure and given transducer we obtain a characteristic resonance pattern, an ultrasonic signature, which can be used as a reference. 

Travel time The larger group velocity for herringbone grain orientation (see Fig. 6(b)) explains the shorter travel time (see A-scans in Fig. 7 and 8). 

An extension of these metliods to 3D is the Feldkamp algorithm [7], a standard in 3D-tomographic reeonstruction today. In this case off-midplane voxels are taken into eonsideration through weighted filtered 3D-baekprojection. llie weighting compensates for the longer way an oblique ray has to travel. 

By means of the pair SI/El a longitudinal wave travels parallel to the object surface. 

It should be pointed out, that one of the existing negative points with bad economical and social consequences is the appearance of false and counterfeit securities, documents, notes as well as traveling cards, identity cards and etc. Each year the number of confiscated counterfeit notes is increased on 10%. 

Edcfy-cufrent NDT inspections using spatial data (sampled scans) ha >e many benefits. They separate the two conflicting aspects of an inspection scanning and signal interpretation. An instrument/display (client/server) based NDT inspection based on sampled scan data aides in the training and certification of inspectors. It can be used over the Internet or in-house Intranet networks to train or examine inspectors at multiple or remote sites. This saves travel time and resources as defects, instrumentation and teaching can all be consolidated Samples can be maintained and distributed from a central certification body providing more control andflexibility. 

The Driving Module houses power supply, circuits for determination of travel distance (odometer wheels) and circumferential orientation, and a computer and a storage facility for all data recorded. The Driving Module has cups extending to the pipe wall, thus providing the movement of the tool after its launching into the continuous oil flow. 

Interferometry is based on the fact that light reflected from the front and back interfaces of a film travels different distances, producing interference effects. The method has been applied to Langmuir-Blodgett films (Section XV-7) and to soap films (Section XrV-8) [147-149]. 

A surfactant for evaporation control has an equilibrium film pressure of 15 dyn/cm. Assume a water surface and 25°C and calculate the distance traveled by the spreading film in 8 sec. 

Fig. VI-4. Illustration of the surface force apparatus with the crossed-cylinder geometry shown as an inset. The surface separations are determined from the interference fringes from white light travelling vertically through the apparatus. At each separation, the force is determined from the deflection in the force measuring spring. For solution studies, the entire chamber is filled with liquid. (From Ref. 29.)...

The situation is complicated, however, because some of the drag on a skidding tire is due to the elastic hysteresis effect discussed in Section XII-2E. That is, asperities in the road surface produce a traveling depression in the tire with energy loss due to imperfect elasticity of the tire material. In fact, tires made of high-elastic hysteresis material will tend to show superior skid resistance and coefficient of friction. 

With certain critical Pco/Poi ratios, structural oscillations can be observed [306]. Patterns of stationary and/or traveling waves can actually be seen by means of photoemission electron microscopy (see Ref. 313, and note Section XVIII-7B. Such behavior can be modeled mathematically (e.g.. Refs. 214, 314). 

An illustrative example is provided by investigating the possible momenta for a single particle travelling in the v-direction, p First, one writes the equation that defines the eigenvalue condition... 

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