Cable velocity

Having calculated the maximum ram speed from the cable velocity V, the delivery volume of the pumps is given hy Q = f x in which / is the piston area of the main plunger. The return speed Vj of the ram may be assumed 10, because it is general practice to rate the... 

The paper discusses the application of dynamic indentation method and apparatus for the evaluation of viscoelastic properties of polymeric materials. The three-element model of viscoelastic material has been used to calculate the rigidity and the viscosity. Using a measurements of the indentation as a function of a current velocity change on impact with the material under test, the contact force and the displacement diagrams as a function of time are plotted. Experimental results of the testing of polyvinyl chloride cable coating by dynamic indentation method and data of the static tensile test are presented. 

For coaxial cables, the following electrical properties related to the dielectric constant of the core material and the dimensions determine the quaUty of the signal impedance, capacitance, attenuation, crosstalk, and time delay and velocity of propagation. 

Time Delay and Velocity of Propagation. Time delay is direcdy proportional to the square root of the dielectric constant and describes the time that it takes for a signal to travel through a cable. The lower the dielectric constant, the less time required for a signal to travel through a cable. 

Velocity of propagation is the speed of transmission in a cable as compared to the speed of transmission in air and is therefore expressed as a percentage. Since the velocity of propagation is inversely proportional to the square root of the dielectric constant of the core, a lower dielectric constant results in higher transmission speed (3). 

Safety Showers. Safety showers and eyewash fountains or hoses should be installed where corrosive or toxic materials are handled. A large-volume, low velocity discharge from directly overhead should effect continuous drenching, ie, a minimum flow of 20 L/min (50 gal /min). Water to outside showers may be heated to a maximum temperature of 27°C by an electric heating cable. The valves for all safety showers should be at the same height and relative position to the shower head, and they should operate in the same way and direction. The shower station should be identified by paint of a bright, contrasting color. In areas where chemicals harmful to the eyes may be encountered, an eyewash fountain or spray should be available in case of splash accidents. 

An impressive demonstration that myosin heads do move along the actin filaments was provided by Sheetz and Spudich, who found that myosin-coated fluorescent beads 0.7 pm in diameter will move along actin filaments from cells of the alga Nitella in an ATP-dependent fashion at velocities similar to those required in muscle.149 The myosin heads literally glide along the thick cables of parallel actin filaments present in these algae. 

For other media, such as insulated cables or cables contained in magnetic shields (conduits, etc.), the velocity of propagation will be slower, as these items are no longer characterized by the free air qualities of p. and e. 

Coaxial cables are commonly used as low-distortion, low-jitter delay lines in timing circuits. The velocity of a current pulse along an ideal cable (Ro, G0 = 0) is given by c = (L0C0)"I/2 2xl08 ms 1. Hence a pulse takes almost exactly 5ns to travel along lm of cable-a handy figure to remember. 

The velocity of the electrical signal in the cable is nearly 10 times faster than the acoustic signal in the delay line, hence the wavelength is nearly 10 times as long in the electrical cables as it is in the acoustic delay line. 

It is of interest to be able to predict the life of a glass fiber, say an optical glass fiber in a cable buried under the sea. The starting point is crack growth velocity versus stress intensity factor, K. Generally, we can express crack velocity, j/as... 

Medard (Refs 25 29) detd some props of aluminized expls and gave a cable comparing Trauzl test values(CUP in Fr)and in some cases deton velocities of nitrocompds contg from 0 to 40% Al. It seems chat in most cases 15 to 20 is the optimum but this amt can be as high as 25% or even 30% when PEJN or RDX is present. Among the aluminized expls investigated by Medard were a)A"n 30 AN 80.2, TNT 10.6 Al 9.2% ... 

On June 08, 1994 a bottom mounted current profiler RDI BB-ADCP 600 kHz was deployed at some hundred meters distance from the station in order to collect current velocity data. The accuracy of the velocity data is of about 0.4 cm/s. On July 15, 2003 this device was replaced by an WH-ADCP 300 kHz device, mounted in a trawl resistant frame 100 m away from and connected to the measuring pile via a cable for power supply and data transmission. Because of the different device type the accuracy of the velocity data has changed to 1.1 cm/s. The uncertainty of depth allocation of the current measurements to the T-S samples is estimated to 0.5 m. The provided data files contain daily mean values averaged from 0 00 to 23 59 UTC at four depth levels for the period from December 1, 1991 to December 31, 2006, including the major inflow events of 1993, 1997, and 2003. 

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