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Air Traffic Control System
Published in Milica Kalić, Slavica Dožić, Danica Babić, Introduction to the Air Transport System, 2022
Milica Kalić, Slavica Dožić, Danica Babić
The vertical position of the aircraft is the height at which the aircraft is at a particular moment of the flight. Depending on the plane that is taken as the basis for determining the vertical position of the aircraft, the height is defined in one of the following ways, Figure 4.2 (ICAO 8168 2018): Elevation (E)—The vertical distance of a level, a point, or an object considered as a point on the ground, measured from a mean sea level (MSL). The pressure set on the subscale of the altimeter so that the instrument indicates its height above MSL is known as QNH pressure. The altimeter will read runway elevation when the aircraft is on the runway.Height (H)—The vertical distance of a level, a point, or an object considered as a point in the air, measured from a specified datum (e.g., runway). The pressure set on the subscale of the altimeter so that the instrument indicates its height above the reference elevation being used is known as QFE pressure. QFE is the air pressure at the current ground level. It is used to cause the altimeter to register height above the ground.Altitude (A)—The vertical distance of an object in the air measured from MSL. It is determined by using QNH pressure.Flight Level (FL)—A surface of constant atmospheric pressure which is related to a specific pressure datum, 1,013.2 hectopascals (hPa) at MSL at standard air pressure. The pressure set on the subscale of the altimeter so that the instrument indicates its height above the reference plane being used is known as QNE pressure. Flight levels are separated from each other at discrete pressure intervals of 18 hPa (this corresponds to a change in height of 500 ft)2 expressed in hundreds of feet. Flight levels are generally expressed as FLxxx, where the xxx is a two- or three-digit number indicating the pressure altitude in units of 100 ft. For example, FL310 corresponds to an altitude of 31,000 ft above MSL when the pressure at sea level is 1,013.2 mb.
Effect of backstroke ledge on backstroke start technique for water entry
Published in Sports Biomechanics, 2023
Daisuke Sato, Hiroshi Suito, Naoyuki Yamashita, Kenta Kusanagi, Takuya Mizukami, Shigehiro Takahashi
Using a BSL significantly increased the flight distance (Table 1), which supports the results of Barkwell and Dickey (2018) and de Jesus et al. (2015). De Jesus et al (2015) reported that using a BSL increased flight distance by improving the vertical position of the CM, vertical and horizontal velocities at take-off, as well as the take-off angle. Similar findings were reported by Barkwell and Dickey (2018) that using a BSL improved flight distance; however, the vertical or horizontal impulse at take-off and take-off angle were unchanged, and the authors did not report the variables of CM at the take-off phase. Our results strengthen the findings of the latter study where using a BSL significantly increased the height of the CM at take-off, thus improving flight distance. Similarly, our results show that neither the vertical velocity of the CM at take-off nor the take-off angle was significantly different between trials.
Promoting uncertainty to support preservice teachers’ reasoning about the tangent relationship
Published in International Journal of Mathematical Education in Science and Technology, 2019
David Glassmeyer, Aaron Brakoniecki, Julie M. Amador
Second, we intentionally set parameters around tool use related to the task in a way that would afford PSTs opportunities to explore uncertainty. PSTs were permitted – and at times prompted – to use protractors, string, graph paper, and technology such as Desmos, GeoGebra and Geometer’s Sketchpad as well as graphing calculators. These tools allowed the PSTs to observe how changing an angle value impacted the vertical position, horizontal position and slope value of the slope triangles formed by that angle. At the same time, PSTs were instructed not to use ‘trigonometry buttons’ on any digital technology; in other words, PSTs were restricted from using calculators or computers to compute values of sine, cosine, or other trigonometric relationships. Restricting students from using technology encouraged PSTs to reason through the task using triangles formed by various angle measures rather than immediately receiving an answer from their calculator. As noted in Kimmons R, Miller B, Amador J, et al. [31], technology use in certain situations can hinder learning, so use should be purposeful and restricted in cases where learning without the technology may be advantageous. The tasks used in this study are best described by what occurred each class day, called Day 1, Day 2 and Day 3, and in the homework assignments between each class.
Adaptive online distributed optimization in dynamic environments
Published in Optimization Methods and Software, 2021
Parvin Nazari, Esmaeil Khorram, Davoud Ataee Tarzanagh
A gradually manoeuvring target in the two-dimensional plane is considered for our experimental evaluations. We assume that each position component of the target evolves independently according to a near constant velocity model. The state of the target at each time t, denoted by , consists of four parts: horizontal position, vertical position, horizontal velocity, and vertical velocity. Hence, using the dynamic , we consider the following linear state space model where is the system noise.