Travel time

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

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). 

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. 

NASA is also considering a more advanced aircraft such as Mach 5 to cut Pacific travel time to about three hours, but in this case kerosene fuel is no longer acceptable, and Hquefted natural gas or Hquefted hydrogen would be needed to provide the necessary cooling and stabiUty. However, a completely new fueling system would be required at every international airport to handle these cryogenic fluids. 

The latter is generally necessary for devices with long travel times, such as flush-fitting reactor discharge valves that are motor-driven. 

The effec t of wind speed is twofold (1) Wind speed will determine the travel time from a source to a given receptor and (2) wind speed... 

The factor 2 is considered to account for the refleetion of the incident surge at the equipment (equation (18.3)) T = travelling time of the surge to reach the equipment from the arrester terminals. 

Z, = surge impedance of the affected line T = travelling time of the switching surge in us II = number of consecutive discharges... 

Transformations due to chemical reactions throughout the plume are frequently treated as exponential losses with time. The concentration x(0 at travel time t when pollutant loss is considered compared to the concentration X at the same position with no loss is... 

Wind speed also affects the travel time from source to receptor halving of the wind speed will double the travel time. For buoyant sources, plume rise is affected by wind speed the stronger the wind, the lower the plume. Specific equations for estimating plume rise are presented in Chapter 20. 

The horizontal dispersion of a plume has been modeled by the use of expanding cells well mixed vertically, with the chemistry calculated for each cell (31). The resulting simulation of transformation of NO to NO2 in a power plant plume by infusion of atmospheric ozone is a peaked distribution of NO2 that resembles a plume of the primary pollutants, SO2 and NO. The ozone distribution shows depletion across the plume, with maximum depletion in the center at 20 min travel time from the source, but relatively uniform ozone concentrations back to initial levels at travel distances 1 h from the source. 

Uniform mixing in the vertical to 1000 m and uniform concentrations across each puff as it expands with the square root of travel time are assumed. A 0.01 h transformation rate from SO2 to sulfate and 0.029 and 0.007 h" dry deposition rates for SO2 and sulfate, respectively, are used. Wet deposition is dependent on the rainfall rate determined from the surface obser% ation network every 6 h, with the rate assumed to be uniform over each 6-h period. Concentrations for each cell are determined by averaging the concentrations of each time step for the cell, and deposition is determined by totaling all depositions over the period. 

Equation is valid where diffusion in tlie direction of tlie plume travel can be neglected (i.e., no diffusion in the x direction). This is a valid assumption if tlie release is continuous or if tlie duration of release is equal to or greater tlian the travel time x / u from flic source to tlie location of interest. 

Dedicated facilities are often cited for safety purposes, but this, too, is not a simple truth. Most accidents occur at intersections, and dedicated facilities make intersections far more complex. When the Netherlands allowed their moped riders to travel in the auto lanes instead of the bike lanes, the moped accident rate fell by an astounding 70 percent. The bicycle accident rate would be higher if bicyclists tried to ride at brisk speed m these separated bike lanes. The sub-lO-mph speeds that are considered polite in these countries largely allow bicyclists to compensate for the facilities shortcomings, at the expense of travel time. 

Matching the supply of transit service to its demand is the primary determinant of the energy efficiency of transit. The demand for transit depends on income levels and land use. As average income rises, so does the value of travel time, and therefore the cost of time spent traveling. Higher incomes also make automobile use more obtainable. 

An important part of interpreting surface seismic data is the identification of the oil- and gas-bearing zones on the seismic data. Vertical seismic profile (VSPs) data are often recorded with a source on the surface and with receivers down the well to accomplish this task. In this way, the travel time to the reservoir can be measured along with other information relating the well data to the surface seismic data. 

Signal processirtg module determines pressure-wave phase shift (0) and calculates sonic travel time (t) for round-trip t - 0f27t/. 

Sonic travel time should remain constant in gas-free mud. When sonic travel time suddenly increases, an alarm is given. 

Example The auxiliary functions in Figure 51.9 are identified as those work elements performed by the craftsper-son which are part of the job, but which are not apparent after the work is completed. These include such functions as job planning by the craftsman, travel time, obtaining materials, and miscellaneous get-ready and clean-up work. The auxiliary time is affected by the physical facilities involved, such as facility layout, location of shops, degree of material delivery, and so forth. If sufficient studies are taken, the auxiliary work can be related to the direct work and ratios determined for each craft by type of work. 

For smaller chemical volume consumers, especially those with little in the way of in-house BW treatment technical skills, the overall program costs can be relatively high. This typically is due to the disproportionately high requirement for on-site technical service time (including the travel time to and from a customer s site) compared to the volumes of chemical treatment sold. Travel and on-site time is expensive. Typically, the cost of labor and technical service is two to three times the cost of the chemical raw materials used to provide treatments. 

For conic mirrors there is a unique and interesting situation There exists a pair of points in space located relative to a conic mirror such that the light travel time for all possible paths from one point to the other are equal and minimum. This means that aU light leaving one of these points will intersect the other point if it strikes the conic mirror. These points are called conic conjugates. For any given conic there are only two such points, which are different for different conics. 

The travel time for suspended load is controlled by the flow velocity and the distance to the basin outlet. Flow velocities do not change much downstream in a typical river system (Leopold, 1953) and typically range from 0.1 to several m/s. Hence, suspended load should be able to travel at least 10 to 100 km per day and the travel time for suspended sediment to traverse even the longest rivers in the world should be less than a season. Although some of the suspended load will be deposited in floodplains, the component of the suspended load that does not get sequestered in terrestrial depositional environments is delivered almost as fast as the water that it flows in. Bedload travels much more slowly. In mountain drainage basins, the velocity of individual bedload clasts is on the... 

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