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Coastal Navigation—Nautical Charts, Geographic Positioning, Marine Electronics, and Instruments
Published in George A. Maul, The Oceanographer's Companion, 2017
In marine navigation, speed is given in nautical miles per hour or knots (kn). The term “knot” probably came from Bartolomeu Crescêncio of Portugal, at the beginning of the sixteenth century. A line with a chip of wood attached was tossed overboard and the sailor would count the number of knots (spaced every 47.25 feet) passing through his hands in the 28 sec a sandglass would empty (47.25feet28sec×3600sechr≅6076feethr=1kn). The chip-log method gives an estimate of the ship's speed through the water, but not speed over the ground. Oceanographers often work in meters per second (m ⋅ s−1 or m/s) when measuring current speeds, but wind speeds are still mostly stated in knots. For handy reference 1 m ⋅ s−1 = 1.94 kn = 2.24 mph = 3.6 kph = 3.28 fps, where mph is statute miles (5280 feet) per hour, kph is kilometers per hour, and fps is feet per second.
What Is a Supply Chain?
Published in Arthur G. Arway, Supply Chain Security, 2013
Providers who transport material via the high seas are the ocean providers. Container ships of many types embark and disembark material of all types using shipping lanes that crisscross the oceans between the continents. The speed of the ships can be, on average, 25 knots, or approximately 28 mph, over water. Depending upon the size, load, capacity, and weather, a shipment, moving from a North Atlantic port to a port on the west shore of Latin America could take anywhere from seven to eleven weeks (see Figure 1.3).
Equations of motion
Published in Mohammad H. Sadraey, Aircraft Performance, 2017
In terms of speed, one knot is equal to one nautical mile per hour. For cars and trains, statute mile is used in the United States, since statute mile is different from nautical mile. Relationships between various units of speed are as follows: Knot=Nautical mileHour
Integrating storm surge modeling and accessibility analysis for planning of special-needs hurricane shelters in Panama City, Florida
Published in Transportation Planning and Technology, 2023
Jieya Yang, Linoj Vijayan, Mahyar Ghorbanzadeh, Onur Alisan, Eren Erman Ozguven, Wenrui Huang, Simone Burns
The peak storm surge is above FEMA’s 100-year flood risk elevation (Figure 4(b)). Compared to the observed peak water level of 4.74 m in Mexico Beach, Holland 1980 wind model with a radius of 64-knot wind speed for parameter estimation results in the lowest error of 1%. However, wind fields away from the hurricane wall using a radius of 64-knot wind speed for parameter estimation are generally weaker than those using a radius of 34-knot wind speed. As a result, comparing 17 watermark observations along the coast and hourly measurements at NOAA gage in Apalachicola, Holland 2010 wind model using a radius of 34-knot wind speed for parameter estimation shows the minimum average error and root-mean-square error, indicating that Holland 2010 wind model more reasonably describes the wind field outside of the hurricane eyewall.
Investigating the Predictive Validity of the COMPASS Pilot Selection Test
Published in The International Journal of Aerospace Psychology, 2021
Iñaki González Cabeza, Brett Molesworth, Malcolm Good, Carlo Caponecchia, Rasmus Steffensen
The FRASCA FSTD was used to examine pilots’ performance during a single right-hand circuit. The FRASCA FSTD is fitted with a Garmin 1000 flight instrument. The Garmin 1000 captures flight performance data at one-second intervals, including altitude (feet above mean sea level), indicated airspeed (knot), pitch (degree), heading (degree), latitude (degree) and longitude (degree). The Garmin 1000 has a built in timer that was pre-set to 10 seconds and was used in the research. The external visual display comprised two data projectors that presented 160 degrees of visual information to pilots via a curved 180 degree wrap around display (curvature adjusted via the FSTD software to ensure one continuous display). Aircraft engine noise was set at 70 dBA in order to reflect as close as possible the environment pilots would typically experience in the real aircraft (Burgess & Molesworth, 2016; Jang et al., 2014).
A practical method to determine the dynamic fracture strain for the nonlinear finite element analysis of structural crashworthiness in ship–ship collisions
Published in Ships and Offshore Structures, 2018
Yeong Gook Ko, Sang Jin Kim, Jung Min Sohn, Jeom Kee Paik
Based on the computed results of maximum strain-rate indicated in Table 4, an empirical formula is now derived for calculating the strain rate as a function of the collision speed with the assumed dynamic fracture strain as follows: where V is the collision speed in knot. Figure 13 shows the relationship between the maximum strain-rate versus collision speed. It is found from Figure 13 that that the effect of the assumed dynamic fracture strain is negligible, and thus Equation (7) can be simplified as follows: