Unit stream power equations for total load

1979 ◽  
Vol 40 (1-2) ◽  
pp. 123-138 ◽  
Author(s):  
Chih Ted Yang
Keyword(s):  
2019 ◽  
Vol 9 (1) ◽  
pp. 2-11
Author(s):  
Marina Efthymiou ◽  
Frank Fichert ◽  
Olaf Lantzsch

Abstract. The paper examines the workload perceived by air traffic control officers (ATCOs) and pilots during continuous descent operations (CDOs), applying closed- and open-path procedures. CDOs reduce fuel consumption and noise emissions. Therefore, they are supported by airports as well as airlines. However, their use often depends on pilots asking for CDOs and controllers giving approval and directions. An adapted NASA Total Load Index (TLX) was used to measure the workload perception of ATCOs and pilots when applying CDOs at selected European airports. The main finding is that ATCOs’ workload increased when giving both closed- and open-path CDOs, which may have a negative impact on their willingness to apply CDOs. The main problem reported by pilots was insufficient distance-to-go information provided by ATCOs. The workload change is important when considering the use of CDOs.


1987 ◽  
Vol 22 (3) ◽  
pp. 365-376
Author(s):  
C. H. Chan ◽  
L. H. Perkins

Abstract Wet deposition estimates were computed from monthly wet precipitation samples collected in the Lake Superior Basin. Sulphate and nitrogen loadings from wet precipitation corresponded to 142 and 40 thousand tonnes per year. On a percentage basis, wet deposition of sulphate and nitrogen accounted for 21% and 54%, respectively, of the total load. Atmospheric sources for other major ions ranged from 1 to 10%. Atmospheric deposition at the eastern end of Lake Superior was higher than the western end of the Basin. The relative accuracy of these estimates were examined in relation to the changes in lake chemistry in Lake Superior from 1973 to 1983.


Friction ◽  
2021 ◽  
Author(s):  
Longxiang Yang ◽  
Zhanjiang Wang ◽  
Weiji Liu ◽  
Guocheng Zhang ◽  
Bei Peng

AbstractThis work is a supplement to the work of Sneddon on axisymmetric Boussinesq problem in 1965 in which the distributions of interior-stress fields are derived here for a punch with general profile. A novel set of mathematical procedures is introduced to process the basic elastic solutions (obtained by the method of Hankel transform, which was pioneered by Sneddon) and the solution of the dual integral equations. These processes then enable us to not only derive the general relationship of indentation depth D and total load P that acts on the punch but also explicitly obtain the general analytical expressions of the stress fields beneath the surface of an isotropic elastic half-space. The usually known cases of punch profiles are reconsidered according to the general formulas derived in this study, and the deduced results are verified by comparing them with the classical results. Finally, these general formulas are also applied to evaluate the von Mises stresses for several new punch profiles.


2008 ◽  
Vol 367 ◽  
pp. 137-144 ◽  
Author(s):  
Luigino Filice ◽  
Francesco Gagliardi ◽  
Fabrizio Micari

Nowadays, many researchers are involved in studies aimed to the explanation of some peculiar aspects regarding manufacturing processes. In this paper, an experimental campaign was carried out in order to reproduce tube extrusion starting from a cylindrical billet. In particular, the development of a proper equipment is presented: the aim was to measure both the total load, by using the testing machine load cell, and the local pressure value on the porthole. The latter task was carried out performing a proper system based on the use of a small load-cell. The tube was extruded with a good surface quality and the external area does not show any welding line evidence. Pure Lead was used for the experimental analysis; this material was chosen due to its high ductility which allows to carry out the process at room temperature. The material was characterized by compression tests at different strain rates and the obtained material law was used to perform a numerical analysis using SFTC Deform 3D numerical code. The Numerical analysis was carried out to show both the advantages and drawbacks of the modern FE codes when extrusion processes are investigated.


Blood ◽  
1966 ◽  
Vol 28 (2) ◽  
pp. 188-200 ◽  
Author(s):  
MARTIN J. CLINE

Abstract Phagocytosis has profound effects on several aspects of the RNA metabolism of human leukocytes. The major changes induced by particle ingestion appear to be (1) an increased uptake of pyrimidine precursors from the suspending medium, (2) a contraction in the size of the nucleotide pool, (3) an accelerated rate of destruction of preexisting RNA, and (4) an increased rate of RNA synthesis. Sucrose density gradient analysis of the newly synthesized RNA suggests that several classes of RNA are involved in this process. The increased turnover rate of the nucleotide pool and of the cellular RNA of the leukocyte is proportional, within limits, to the total load of ingested particles.


Author(s):  
Carlos D. Gómez-Carmona ◽  
José Pino-Ortega ◽  
Braulio Sánchez-Ureña ◽  
Sergio J. Ibáñez ◽  
Daniel Rojas-Valverde

With the development of new microsensor technology to assess load in sports, some indicators of external load through accelerometry-based data have been created by sport technology companies. Thus, the study aim was to analyze the agreement between different accelerometry-based external load indicators (ABELIs) available in sport science. A U-16 male soccer team was assessed during three official matches, divided by periods, to obtain 3-D accelerometry data (x, y and z axes). An average of 1,420,000 data points was analyzed per axis per player. The ABELIs were calculated using this information, and the agreement between them was explored. The following ABELIs were considered after a literature review: AcelT, Player LoadRT, PlayerLoadTM, Impulse Load, Player LoadRE and Total Load. In order to compare ABELIs, two analyses were performed using: (1) absolute data; and (2) normalized and centered data (Z-scores). In absolute and centered data, very large to nearly perfect correlations (1st period: r > 0.803, p > 0.01; 2nd period: r > 0.919; p > 0.01) were found. Instead, very large differences were found in absolute values (bias = −579,226.6 to 285,931.1; t = −224.66 to 213.91, p < 0.01), and no differences in scaled and centered values (bias = 0; t = 1; p = 1). In conclusion, considering the different output (magnitude and units) among ABELIs, the standardization of a universal index to calculate accelerometer load is needed in order to make possible between-study comparison.


2017 ◽  
Vol 12 (9) ◽  
pp. 1218-1223 ◽  
Author(s):  
Jared A. Bailey ◽  
Paul B. Gastin ◽  
Luke Mackey ◽  
Dan B. Dwyer

Context:Most previous investigations of player load in netball have used subjective methodologies, with few using objective methodologies. While all studies report differences in player activities or total load between playing positions, it is unclear how the differences in player activity explain differences in positional load. Purpose:To objectively quantify the load associated with typical activities for all positions in elite netball. Methods:The player load of all playing positions in an elite netball team was measured during matches using wearable accelerometers. Video recordings of the matches were also analyzed to record the start time and duration of 13 commonly reported netball activities. The load associated with each activity was determined by time-aligning both data sets (load and activity). Results:Off-ball guarding produced the highest player load per instance, while jogging produced the greatest player load per match. Nonlocomotor activities contributed least to total match load for attacking positions (goal shooter [GS], goal attack [GA], and wing attack [WA]) and most for defending positions (goalkeeper [GK], goal defense [GD], and wing defense [WD]). Specifically, centers (Cs) produced the greatest jogging load, WA and WD accumulated the greatest running load, and GS and WA accumulated the greatest shuffling load. WD and Cs accumulated the greatest guarding load, while WD and GK accumulated the greatest off-ball guarding load. Conclusions:All positions exhibited different contributions from locomotor and nonlocomotor activities toward total match load. In addition, the same activity can have different contributions toward total match load, depending on the position. This has implications for future design and implementation of position-specific training programs.


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