scholarly journals Early starts and late finishes both reduce alertness and performance among short‐haul airline pilots

2021 ◽  
Author(s):  
Lucia Arsintescu ◽  
Sean Pradhan ◽  
Ravi G. Chachad ◽  
Kevin B. Gregory ◽  
Jeffrey B. Mulligan ◽  
...  
Keyword(s):  
Airline Pilots ◽  
And Performance

292 Rest Schemes and Inflight Sleep Duration on Long Range and Ultra-Long Range Commercial Airline Routes

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A117-A117
Author(s):  
Michael Rempe ◽  
Ian Rasmussen ◽  
Gregory Belenky ◽  
Amanda Lamp
Keyword(s):  
Long Range ◽  
Strong Predictor ◽  
Sleep Time ◽  
Wide Distribution ◽  
Pilot Performance ◽  
Airline Pilots ◽  
Sleep Timing ◽  
Commercial Airline ◽  
United Airlines ◽  
And Performance

Abstract Introduction Pilots flying long range (LR; 8-16 hour) and ultra-long range (ULR; 16+ hour on 10% of trips) commercial airline routes use a variety of work/rest schedules during flights, resulting in a wide distribution of total inflight sleep time (TIFS) amounts. Since sleep is a strong predictor of performance, it is important to quantify TIFS and determine rest scheme patterns that optimize sleep opportunity and subsequent alertness and performance. Here we report rest schemes for pilots on LR and ULR routes and longer TIFS values than previously reported. These rest schemes can serve as templates to increase TIFS and improve pilot performance, particularly on ULR routes. Methods 427 commercial airline pilots provided data for this sub-study that was part of a larger study on Fatigue Risk Management System (FRMS) routes. Inflight sleep timing and duration were measured on 3 LR and 5 ULR routes. Inflight sleep times were self-reported in a sleep/work logbook and verified using actigraphy. Results Most outbound and inbound landing crews took one break during the second half of the flight (average LR TIFS=4.0 hr; average ULR TIFS=4.9 hr), while most outbound and inbound relief crews consequently took one break during the first half of the flight (average LR TIFS=3.5 hr; average ULR TIFS=4.5 hr). However, three of the five ULR routes used more complex split rest schemes for landing and relief crews, primarily on outbound flights (average TIFS=5.0 hr). Across all routes and both crews, the maximum average TIFS reached ~6 hours. Conclusion Our results indicate that pilots on average are sleeping inflight more than previous studies demonstrated. Additionally, we found that crews on some ULR flights used more complicated rest schemes, but still generally preferred 2 or 3 breaks. These findings have implications for airline procedures and aviation policies by showing that pilots may be sleeping longer than originally expected on LR and ULR flights. Recommending rest schemes that allow for the greatest inflight sleep opportunity may provide the best chance for inflight recuperation, especially before the Top of Descent critical phase of flight. Support (if any) United Airlines

Congruent and Spurious Motion in the Learning and Performance of a Compensatory Tracking Task

1972 ◽  
Vol 14 (3) ◽  
pp. 259-269 ◽  
Author(s):  
Joseph G. Guercio ◽  
Robert L. Wall
Keyword(s):  
Vehicle Dynamics ◽  
Tracking Error ◽  
Angular Acceleration ◽  
Tracking Task ◽  
Motion Information ◽  
Airline Pilots ◽  
Learning Time ◽  
Moving Base ◽  
And Performance ◽  
The Relationship

The importance of congruent and spurious yaw motion in compensatory tracking by eight airline pilots was examined. The pilots, seated erect in the Ames Man-Carrying Rotation Device (MCRD), tracked with k/s+1 and k/s(s+1) vehicle dynamics in fixed- and moving-base simulation. Following the learning phase of the experiment, five levels of spurious angular acceleration were superimposed on the motion of the MCRD. Learning of the tracking task was found to be a function of both vehicle dynamics and mode of simulation. The presence of congruent motion information reduced learning time in k/s(s+1) vehicle dynamics and resulted in lower tracking error in both vehicle dynamics. The spurious angular accelerations resulted in an increase in pilot tracking error; however, the relationship between the magnitude of the acceleration and its effect was highly complex. The data suggest that the minimal disturbance level for spurious angular accelerations during tracking is below 0.4°/sec.2.

Transmission Scanning Electron Microscopy and Energy Analysis with the Siemens ELMISKOP 101

1972 ◽  
Vol 30 ◽  
pp. 450-451
Author(s):  
H. M. Thieringer
Keyword(s):  
Objective Lens ◽  
Transmission Microscopy ◽  
Image Recording ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Electron Microscopes ◽  
And Performance ◽  
Convergent Beam ◽  
Ray Path ◽  
Beam Diffraction

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.

Angular Resolved Electron Spectroscopy with Parallel Recording

1990 ◽  
Vol 48 (2) ◽  
pp. 370-371
Author(s):  
Huang Min ◽  
P.S. Flora ◽  
C.J. Harland ◽  
J.A. Venables
Keyword(s):  
Electron Spectroscopy ◽  
Low Voltage ◽  
Solid Angle ◽  
Detection System ◽  
Voltage Electron ◽  
Cylindrical Mirror ◽  
Inner Radius ◽  
Channel Plate ◽  
And Performance ◽  
Type Detector

A cylindrical mirror analyser (CMA) has been built with a parallel recording detection system. It is being used for angular resolved electron spectroscopy (ARES) within a SEM. The CMA has been optimised for imaging applications; the inner cylinder contains a magnetically focused and scanned, 30kV, SEM electron-optical column. The CMA has a large inner radius (50.8mm) and a large collection solid angle (Ω > 1sterad). An energy resolution (ΔE/E) of 1-2% has been achieved. The design and performance of the combination SEM/CMA instrument has been described previously and the CMA and detector system has been used for low voltage electron spectroscopy. Here we discuss the use of the CMA for ARES and present some preliminary results.The CMA has been designed for an axis-to-ring focus and uses an annular type detector. This detector consists of a channel-plate/YAG/mirror assembly which is optically coupled to either a photomultiplier for spectroscopy or a TV camera for parallel detection.

Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

1989 ◽  
Vol 47 ◽  
pp. 1000-1001
Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby
Keyword(s):  
Electron Microscopy ◽  
Flow Rate ◽  
Succinic Anhydride ◽  
Volume Flow Rate ◽  
Mass Density ◽  
Uranyl Acetate ◽  
Volume Flow ◽  
Base Resin ◽  
And Performance ◽  
Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

Trace nanoanalysis

1994 ◽  
Vol 52 ◽  
pp. 940-941
Author(s):  
D. E. Newbury ◽  
R. D. Leapman
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Detection Efficiency ◽  
Volume Element ◽  
And Performance ◽  
Trace Constituents ◽  
Secondary Ion ◽  
Concentration Levels ◽  
Structure Properties

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).

Relationship of stress and performance among first-year dental students

1986 ◽  
Vol 50 (5) ◽  
pp. 264-267 ◽  
Author(s):  
GH Westerman ◽  
TG Grandy ◽  
JV Lupo ◽  
RE Mitchell
Keyword(s):  
Dental Students ◽  
First Year ◽  
And Performance ◽  
Relationship Of

Linguistic Competence in Aphasia

2008 ◽  
Vol 17 (3) ◽  
pp. 87-92
Author(s):  
Leonard L. LaPointe
Keyword(s):  
Language Use ◽  
Linguistic Competence ◽  
Careful Study ◽  
Feral Children ◽  
Performance Factors ◽  
Performance Loss ◽  
Linguistic Rules ◽  
Communication Goals ◽  
Aphasia Treatment ◽  
And Performance

Abstract Loss of implicit linguistic competence assumes a loss of linguistic rules, necessary linguistic computations, or representations. In aphasia, the inherent neurological damage is frequently assumed by some to be a loss of implicit linguistic competence that has damaged or wiped out neural centers or pathways that are necessary for maintenance of the language rules and representations needed to communicate. Not everyone agrees with this view of language use in aphasia. The measurement of implicit language competence, although apparently necessary and satisfying for theoretic linguistics, is complexly interwoven with performance factors. Transience, stimulability, and variability in aphasia language use provide evidence for an access deficit model that supports performance loss. Advances in understanding linguistic competence and performance may be informed by careful study of bilingual language acquisition and loss, the language of savants, the language of feral children, and advances in neuroimaging. Social models of aphasia treatment, coupled with an access deficit view of aphasia, can salve our restless minds and allow pursuit of maximum interactive communication goals even without a comfortable explanation of implicit linguistic competence in aphasia.

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