Optical Quality, Threshold Target Identification and Military Target Task Performance After Advanced Keratorefractive Surgery

2010 ◽  
Author(s):  
Kraig S. Bower
Keyword(s):  
Task Performance ◽  
Target Identification ◽  
Optical Quality ◽  
Target Task ◽  
Keratorefractive Surgery ◽  
Quality Threshold

scholarly journals MULTIPOLAR: Multi-Source Policy Aggregation for Transfer Reinforcement Learning between Diverse Environmental Dynamics

2020 ◽  
Author(s):  
Mohammadamin Barekatain ◽  
Ryo Yonetani ◽  
Masashi Hamaya
Keyword(s):  
Reinforcement Learning ◽  
Task Performance ◽  
Experimental Evaluation ◽  
Control Problems ◽  
Target Task ◽  
Learning Efficiency ◽  
Simulated Environments ◽  
Discrete Action ◽  
Key Techniques ◽  
Action Spaces

Transfer reinforcement learning (RL) aims at improving the learning efficiency of an agent by exploiting knowledge from other source agents trained on relevant tasks. However, it remains challenging to transfer knowledge between different environmental dynamics without having access to the source environments. In this work, we explore a new challenge in transfer RL, where only a set of source policies collected under diverse unknown dynamics is available for learning a target task efficiently. To address this problem, the proposed approach, MULTI-source POLicy AggRegation (MULTIPOLAR), comprises two key techniques. We learn to aggregate the actions provided by the source policies adaptively to maximize the target task performance. Meanwhile, we learn an auxiliary network that predicts residuals around the aggregated actions, which ensures the target policy's expressiveness even when some of the source policies perform poorly. We demonstrated the effectiveness of MULTIPOLAR through an extensive experimental evaluation across six simulated environments ranging from classic control problems to challenging robotics simulations, under both continuous and discrete action spaces. The demo videos and code are available on the project webpage: https://omron-sinicx.github.io/multipolar/.

Effects of Depth Information on Visual Target Identification Task Performance in Shared Gaze Environments

2020 ◽  
Vol 26 (5) ◽  
pp. 1934-1944
Author(s):  
Austin Erickson ◽  
Nahal Norouzi ◽  
Kangsoo Kim ◽  
Joseph J. LaViola ◽  
Gerd Bruder ◽  
...  
Keyword(s):  
Task Performance ◽  
Visual Target ◽  
Target Identification ◽  
Depth Information ◽  
Identification Task ◽  
Shared Gaze

Military target task performance after wavefront-guided (WFG) and wavefront-optimized (WFO) photorefractive keratectomy (PRK)

2014 ◽  
Author(s):  
Tana Maurer ◽  
Dawne Deaver ◽  
Christopher Howell ◽  
Steve Moyer ◽  
Oanh Nguyen ◽  
...  
Keyword(s):  
Task Performance ◽  
Photorefractive Keratectomy ◽  
Target Task

The effects of 7.5% carbon dioxide inhalation on task performance in healthy volunteers

2011 ◽  
Vol 26 (4) ◽  
pp. 487-496 ◽  
Author(s):  
Alison Diaper ◽  
David J Nutt ◽  
Marcus R Munafò ◽  
Joanna L White ◽  
Eric W Farmer ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Blood Pressure ◽  
Heart Rate ◽  
Task Performance ◽  
Target Identification ◽  
Subjective Measures ◽  
Simple Task ◽  
Time Component ◽  
And Performance ◽  
Complex Target

Studies have shown that anxiety can positively or negatively affect performance with respect to focusing of attention or distractibility, subjective workload and effort ( Humphreys and Revelle, 1984 ). The inhalation of carbon dioxide (CO2) is associated with physiological and psychological effects of anxiety ( Bailey et al., 2005 ) but its effects on performance have rarely been reported. The studies reported here looked at the effects of CO2 inhalation on physiological and subjective measures and performance on two tasks. Eight healthy male participants completed a tracking task with a reaction time component, and 12 healthy participants (six male) completed a complex target identification task. Tasks were performed during 20-min inhalations of 7.5% CO2/21% O2/71.5% N2 mixture or medical air. Continuous heart rate and blood pressure measures were taken, in addition to subjective measures of mood and workload. In comparison with air, CO2 increased heart rate and blood pressure, increased subjective scores of panic, anxiety, fear, and tension, and reduced subjective scores of relaxation and happiness. Attention was focussed when inhaling CO2 during the simple task, and central demand was greater when inhaling CO2 during the complex task. Therefore, inhalation of 7.5% CO2 produces effects on task performance which are consistent with anxiety.

Psychometric Measures of Task Difficulty Under Varying Levels of Information Load

1981 ◽  
Vol 25 (1) ◽  
pp. 518-521 ◽  
Author(s):  
Wade R. Helm
Keyword(s):  
Task Performance ◽  
Task Difficulty ◽  
Discrimination Task ◽  
Target Identification ◽  
Simultaneous Presentation ◽  
Performance Ratio ◽  
Information Load ◽  
Psychometric Measures ◽  
Sternberg Task ◽  
Or Task

Two experiments were performed to determine the efficiency of male and female subjects in estimating task difficulty and task performance relative to actual task performance. In experiment 1, three groups (N = 24) used one of three types of scales to rate either task difficulty or task performance on a four-choice discrimination task varied across 7 levels of information load. Correlations of .95, .89 and .85 were obtained between actual task performance and ratings of task performance, ratio ratings of task difficulty and category ratings of task difficulty respectively. In experiment two, two groups (N = 32) used either a ratio or category scale to rate task difficulty on each of four tasks: a four-choice discrimination task, a Sternberg target identification task, a random presentation of the four-choice or Sternberg task and the simultaneous presentation of the four-choice and Sternberg tasks. Each of the four tasks were equated in information load and varied across 7 levels. Analysis of variance indicated that the ratio ratings of task difficulty more accurately reflected actual task performance over all four tasks than did the category ratings of task difficulty. In both experiments no sex differences were noted in either task performance or task ratings.

Analysis of Sputtered Zinc Oxide Films

1980 ◽  
Vol 38 ◽  
pp. 416-417
Author(s):  
T. A. Emma ◽  
M. P. Singh
Keyword(s):  
Electron Microscopy ◽  
Zinc Oxide ◽  
Piezoelectric Materials ◽  
Oxide Films ◽  
Optical Quality ◽  
Zno Films ◽  
Rf Power ◽  
X Ray Diffraction ◽  
Sputtered Films ◽  
Zinc Oxide Films

Optical quality zinc oxide films have been characterized using reflection electron diffraction (RED), replication electron microscopy (REM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Significant microstructural differences were observed between rf sputtered films and planar magnetron rf sputtered films. Piezoelectric materials have been attractive for applications to integrated optics since they provide an active medium for signal processing. Among the desirable physical characteristics of sputtered ZnO films used for this and related applications are a highly preferred crystallographic texture and relatively smooth surfaces. It has been found that these characteristics are very sensitive to the type and condition of the substrate and to the several sputtering parameters: target, rf power, gas composition and substrate temperature.

Effects of Concurrent Manual Task Performance on Connected Speech Acoustics in Individuals With Parkinson Disease

2019 ◽  
Vol 62 (7) ◽  
pp. 2099-2117 ◽  
Author(s):  
Jason A. Whitfield ◽  
Zoe Kriegel ◽  
Adam M. Fullenkamp ◽  
Daryush D. Mehta
Keyword(s):  
Task Performance ◽  
Speech Production ◽  
Dual Task ◽  
Motor Task ◽  
Task Condition ◽  
Connected Speech ◽  
Speech Acoustics ◽  
Single Task ◽  
Manual Task ◽  
Task Conditions

Purpose Prior investigations suggest that simultaneous performance of more than 1 motor-oriented task may exacerbate speech motor deficits in individuals with Parkinson disease (PD). The purpose of the current investigation was to examine the extent to which performing a low-demand manual task affected the connected speech in individuals with and without PD. Method Individuals with PD and neurologically healthy controls performed speech tasks (reading and extemporaneous speech tasks) and an oscillatory manual task (a counterclockwise circle-drawing task) in isolation (single-task condition) and concurrently (dual-task condition). Results Relative to speech task performance, no changes in speech acoustics were observed for either group when the low-demand motor task was performed with the concurrent reading tasks. Speakers with PD exhibited a significant decrease in pause duration between the single-task (speech only) and dual-task conditions for the extemporaneous speech task, whereas control participants did not exhibit changes in any speech production variable between the single- and dual-task conditions. Conclusions Overall, there were little to no changes in speech production when a low-demand oscillatory motor task was performed with concurrent reading. For the extemporaneous task, however, individuals with PD exhibited significant changes when the speech and manual tasks were performed concurrently, a pattern that was not observed for control speakers. Supplemental Material https://doi.org/10.23641/asha.8637008

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