Maximum distance

The transducers discussed above were designed to propagate waves in both directions normal to the direction of the fingers. It has been shown [17] that they produce a roughly collimated beam so they can be used to inspect a band of structure whose width is the transducer finger length the maximum distance away from the transducer covered by the beam is dependent on the attenuation of the wave and the signal-noise ratio, but is typically around 1-2 m in a... 

The maximum distance between transmitter and receiver is 350 mm. The transmitter on the probe can be rotated making it possible to perform a sequence of scans on a perticular weld and on neighbouring welds without moving the microphone collar. 

Visibihty or visual range is the maximum distance at which a black object, a target, can be distinguished from the horizon. Under certain viewing conditions, the apparent contrast (C) between a target and the horizon decreases exponentially with the distance (x) between the target and observer (42)... 

The hazard posed can be limited by maintaining a zone free of people and property around a storage area of explosive material. The minimum radius of the zone depends on the type and quantity of explosive, the extent and type of barrica ding, and the magnitude of loss that would be encountered if an explosive incident occurred. The maximum distance to which hazardous explosive effects propagate depends on the blast overpressure created, which as a first approximation is a function of the cube root of the explosive weight, W. This is termed the quantity distance and is defined as... 

Control Room. The control room location can be critical to the efficient operation of a faciHty. One prime concern is to locate it the maximum distance from the most ha2ardous units. These units are usually the units where LPG or other flammables, eg, hydrocarbons that are heavier than air, can be released and accumulate at grade level. Deadly explosions can occur if a pump seal on a light-ends system fails and the heavier-than-air hydrocarbons coUect and are ignited by a flammable source. Also, the sulfur recovery unit area should be kept at a healthy distance away as an upset can cause deadly fumes to accumulate. 

The ionosphere is part of the larger magnetosphere, a cavity in the stream of particles from the sun. The cavity is produced by the earth s magnetic field (56,57). The ionosphere and the Van AHen radiation belt He within the plasmasphere, which extends to a maximum distance of about 15,000 km above the earth s surface. 

When a pitch is tested for ductility, the sample either suffers britde fracture without elongation or elongates to the maximum distance without breaking. When tested at increased temperatures at a particular point, ie, the ductility point, the behaviour changes from the first type to the second. 

In assessing the hazard of a UVCE or in investigating a UVCE it is often necessary to (1) estimate the maximum distance to the lower flammable hmit (LFL) and (2) determine the amount of gas in a vapor cloud above the LFL. Figure 26-31 shows the maximum distance to the lower flammable limit, i.e., in the centerline of the cloud, based on the previous method from Bodurtha (1980) for wind speeds of 1 iti/s (2.2 mi/h) and 5 m/s (11 mi/h). Maximum concentrations probably occur near 1 m/s. The volume of fuel from the LFL up to 100 percent may be estimated by... 

Assume a continuous release of pressurized, hquefied cyclohexane with a vapor emission rate of 130 g moLs, 3.18 mVs at 25°C (86,644 Ib/h). (See Discharge Rates from Punctured Lines and Vessels in this sec tion for release rates of vapor.) The LFL of cyclohexane is 1.3 percent by vol., and so the maximum distance to the LFL for a wind speed of 1 iti/s (2.2 mi/h) is 260 m (853 ft), from Fig. 26-31. Thus, from Eq. (26-48), Vj 529 m 1817 kg. The volume of fuel from the LFL up to 100 percent at the moment of ignition for a continuous emission is not equal to the total quantity of vapor released that Vr volume stays the same even if the emission lasts for an extended period with the same values of meteorological variables, e.g., wind speed. For instance, in this case 9825 kg (21,661 lb) will havebeen emitted during a 15-min period, which is considerablv more than the 1817 kg (4005 lb) of cyclohexane in the vapor cloud above LFL. (A different approach is required for an instantaneous release, i.e., when a vapor cloud is explosively dispersed.) The equivalent weight of TNT may be estimated by... 

The maximum distance that a 1-psi overpressure will be felt is estimated to be 500 meters. 

Objects close to us are easily perceived, but as we attempt to detect objects farther and farther away from us, the contrast between the object and the background decreases. The lowest limit of contrast for human observers is called the threshold contrast and is important because this value influences the maximum distance at which we can see various objects. 

When using the automated distance array, SCREEN prompts the user for a minimum and maximum distance to use, which should be input in free format, i.e., separated by a comma or a space. SCREEN then calculates the maximum concentration across a range of meteorological conditions for the... 

Thus, the user can input the minimum site boundary distance as the minimum distance for calculation and obtain a concentration estimate at the site boundary and beyond, while ignoring distances less than the site boundary. If the automated distance array is used, then the SCREEN model will use an iteration routine to determine the maximum value and associated distance to the nearest meter. If the minimum and maximum distances entered do not encompass the true maximum concentration, then the maximum value calculated by SCREEN may not be the true maximum. Therefore, it is recommended that the maximum distance be set sufficiently large initially to ensure that the maximum concentration is found. This distance will depend on the source, and some trial and error may be necessary however, the user can input a distance of 50,000 m to examine the entire array. The iteration routine stops after 50 iterations and prints out a message if the maximum is not found. Also, since there may be several local maxima in the concentration distribution associated with different wind speeds, it is possible that SCREEN will not identify the overall maximum in its iteration. This is not likely to be a frequent occurrence, but will be more likely for stability classes C and D due to the larger number of wind speeds examined. 

Air throw The maximum distance from the outlet of an ATD to a plane tangential to the jet envelope and perpendicular to the initial jet section where the velocity is reduced to a predetermined level. 

Stopping distance The maximum distance a moving particle will travel in still air after all the external forces are removed. In the Stokes region it is the velocity of the particle times the relaxation time. 

A fireball involving approximately 800 m (28,000 ft ) of isobutane resulted from the sphere s failure. Several BLEVEs of smaller vertical and horizontal tanks occurred soon thereafter. Tank failures were mainly seam-related. Parts were thrown in various directions up to a maximum distance of 135 m (440 ft). 

Figure 7-68. Maximum allowable length of a vessel vented at one end, or maximum distance between vents as a function of the vent diameter for the safe venting of deflagrations of dusts and gases. By permission, American Institute of Chemical Engineers, Meeting Mar. 6, 1988 by I. Swift (deceased) [56], with data from Ref. [54].

Four equivalent ip -hybridized orbitals achieve maximum distance from one another when they arrange in a tetrahedral structure ... 

The first step in the DG calculations is the generation of the holonomic distance matrix for aU pairwise atom distances of a molecule [121]. Holonomic constraints are expressed in terms of equations which restrict the atom coordinates of a molecule. For example, hydrogen atoms bound to neighboring carbon atoms have a maximum distance of 3.1 A. As a result, parts of the coordinates become interdependent and the degrees of freedom of the molecular system are confined. The acquisition of these distance restraints is based on the topology of a model structure with an arbitrary, but energetically optimized conformation. 

As a consequence of the aforementioned discretization, the number of test points Np, and the linear cutoff Nx in the mode decomposition turn out to be closely related. Denoted by Ax, the typical linear distance between two adjacent test points, Ax must be small enough to ensure that the integral function E is well approximated by the sum E, i. e., Ax must fulfil the condition c(x + Ax) c(x). This is to say that the length scale Ax directly determines the minimal length scale contribution of the Fourier modes, which is Lr/Nx. Consequently, after having fixed N, the spatial variation of c(x) as a function of the number of test points Np has to be carefully monitored to determine the maximum distance Ax ensuring that c(x + Ax) c(x) in the entire box. Typically, for N = 8, we have found that a minimum of 233 test points in a box of unit length is necessary. 

If an error of 10% due to the simplification is accepted the maximum distance of the phase front to the heat exchanger surface smax is given in Table 22. For a typical heat transfer coefficient if water is taken as heat transfer fluid, two different cases can be observed. For the pure PCM, the maximum thickness allowed before the simplification leads to serious errors in the result is only 0.5 mm. In that case the simplification is of no practical use. If the... 

For aqueous solutions at 25°C, rmin = 3.057 x 10-10 ztzk (in metres), i.e. about 0.3 nm, for a uni-univalent electrolyte and about 1.4 nm for a bi-bivalent electrolyte. This distance is considered to be the maximum distance beyond which formation of ion pairs does not occur. 

Again for illustration purpose, we supposedly have chosen Kc such that KcKvKpKm = 5, and xp is the mixing process time constant. Find, without trial-and-error and without further approximation, the maximum distance L that the photodetector can be placed downstream such that the system remains stable. (There are two ways to get the answer. The idea of using magnitude and phase... 

The maximum distance the styrene must travel horizontally is around 300 ft. The total distance traveled inside pipes is 390 ft. If a pressure drop of 2 psi per 100 ft is assumed, the pressure drop due to friction will be about 8 psi (20.5 ft of styrene) and that due to elevation is 90 ft. The total pressure drop is 110.5 ft. Usually for normal flow rates the pressure drop due to the change of velocity is ignored. 

This will be a positive-pressure system, since each dryer will feed 5 extruders. It will be designed to run at the same rate as each dryer, 9,210 lb P.S./hr. The vertical rise is 30 ft and the maximum distance traveled is 130 ft. Because powder is being conveyed a cyclone separator will be specified for each of the extruders. The blowers should be designed to have an LHP of 7.2 and a BHP of 8.4. The power required to operate both is 12.6 kw. 

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