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VASCAR (Visual Average Speed Computer And Recorder) is a type of device for calculating the speed of a moving vehicle. The first VASCAR device was created in 1966 by Arthur Marshall. [ 1 ] It is used by police officers to enforce speed limits , and may be preferred where radar or lidar is illegal, such as some jurisdictions in Pennsylvania ...
Cutting speed may be defined as the rate at the workpiece surface, irrespective of the machining operation used. A cutting speed for mild steel of 100 ft/min is the same whether it is the speed of the cutter passing over the workpiece, such as in a turning operation, or the speed of the cutter moving past a workpiece, such as in a milling operation.
1×10 −1: multiplication of two 10-digit numbers by a 1940s electromechanical desk calculator [1] 3×10 −1: multiplication on Zuse Z3 and Z4, first programmable digital computers, 1941 and 1945 respectively; 5×10 −1: computing power of the average human mental calculation [clarification needed] for multiplication using pen and paper
For CDs, the 1× writing speed is equivalent to the 1× reading speed, which in turn represents the speed at which a piece of media can be read in its entirety, 74 minutes. Those 74 minutes come from the maximum playtime that the Red Book (audio CD standard) specifies for a digital audio CD (CD-DA); although now, most recordable CDs can hold 80 ...
All but the earliest machines had high-speed mechanical feeders to process cards at rates from around 100 to 2,000 per minute, sensing punched holes with mechanical, electrical, or, later, optical sensors. The operation of many machines was directed by the use of a removable plugboard, control panel, or connection box.
Before standard benchmarks were available, average speed rating of computers was based on calculations for a mix of instructions with the results given in kilo instructions per second (kIPS). The most famous was the Gibson Mix, [2] produced by Jack Clark Gibson of IBM for scientific applications in 1959. Other ratings, such as the ADP mix which ...
The first HDD [11] had an average seek time of about 600 ms. [12] and by the middle 1970s, HDDs were available with seek times of about 25 ms. [13]Some early PC drives used a stepper motor to move the heads, and as a result had seek times as slow as 80–120 ms, but this was quickly improved by voice coil type actuation in the 1980s, reducing seek times to around 20 ms.
The comptometer-type calculator was the first machine to receive an all-electronic calculator engine in 1961 (the ANITA mark VII released by Sumlock comptometer of the UK). In 1890 W. T. Odhner got the rights to manufacture his calculator back from Königsberger & C , which had held them since it was first patented in 1878, but had not really ...