An Adaptive Vigilance Task with Knowledge of Results

1974 ◽  
Vol 16 (4) ◽  
pp. 333-338 ◽  
Author(s):  
Earl L. Wiener
Keyword(s):  
Detection Rate ◽  
Adaptive Strategies ◽  
Vigilance Task ◽  
Performance Measure ◽  
The Other ◽  
False Alarms ◽  
Past Performance ◽  
Knowledge Of Results ◽  
Computer Controlled ◽  
Traditional Performance

Four groups of subjects performed a 48-min, computer-controlled, visual watch-keeping task. Two groups were run under fixed, non-adaptive conditions, one with immediate knowledge of results (KR) and the other without (NKR). The KR group showed the usual superiority in detection rate over the NKR group, and made fewer commissive errors (false alarms). Two other groups, also KR and NKR, ran under adaptive conditions, wherein the size of the signals they watched for was adjusted during the vigil according to past performance, so as to maintain a preset detection rate. The resulting curves for the adaptive variable closely resembled the traditional performance measure, detection rate. Various adaptive strategies are discussed.

scholarly journals On the Use of Single-, Dual-, and Quad-Polarimetric SAR Observation for Landslide Detection

2019 ◽  
Vol 8 (9) ◽  
pp. 384 ◽  
Author(s):  
Park ◽  
Lee
Keyword(s):  
Remote Sensing ◽  
Detection Rate ◽  
Detection Method ◽  
Incidence Angle ◽  
Accuracy Assessment ◽  
Temporal Variations ◽  
The Other ◽  
Synthetic Aperture ◽  
False Alarms ◽  
Simple Change

Remote sensing technologies, particularly with Synthetic Aperture Radar (SAR) system, can provide timely and critical information to assess landslide distributions over large areas. Most space-borne SAR systems have been operating in different polarimetric modes to meet various operational requirements. This study aims to discuss how much detectability can be expected in the landslide map produced from the single-, dual-, and quad-polarization modes of observation. The experimental analysis of the characteristic changes of PALSAR-2 signals showed that quad-polarization parameters indicating signal depolarization properties revealed noticeable landslide-induced temporal changes for all local incidence angle ranges. To produce a landslide map, a simple change detection method based on characteristic scattering properties of landslide areas was proposed. The accuracy assessment results showed that the depolarization parameters, such as the co-pol coherence and polarizing contribution, can identify areas affected by landslides with a detection rate of 60%, and a false-alarm rate of 5%. On the other hand, the single- or dual-pol parameters can only be expected to provide half the accuracy with significant false-alarms in areas with temporal variations independent of landslides.

scholarly journals Exploring Sex Differences in Vigilance Performance with Knowledge of Results

2019 ◽  
Vol 63 (1) ◽  
pp. 1321-1325
Author(s):  
Grace E. Waldfogle ◽  
Michaela R. Hagerty-Koller ◽  
Lindsey R. Lane ◽  
Allison E. Garibaldi ◽  
James L. Szalma
Keyword(s):  
Sex Differences ◽  
Individual Differences ◽  
Sustained Attention ◽  
Vigilance Task ◽  
Task Structure ◽  
False Alarms ◽  
Vigilance Performance ◽  
Knowledge Of Results ◽  
Sex Influence

Vigilance, also referred to as sustained attention, is the ability to maintain attention for extended periods of time while monitoring for, oftentimes, critical signals. In attempt to aid performance decrements in vigilance tasks, previous research has examined the effects of knowledge of results (KR). In essence, KR provides feedback on performance, and is argued to enhance the understanding of task structure and motivation to complete the task successfully. However, relatively little is known about how individual differences, such as observer sex, influence KR effects in vigilance. In the present study, 73 observers completed a 25-minute vigilance task in which they were required to monitor flight paths. Observers were randomly assigned to either a KR condition, in which feedback was given for correct detections, false alarms, and misses, or a control condition, where no feedback was provided. The results indicated that small sex differences were found for correct detections and false alarms, as a function of KR.

Practice Effects on a Visual Vigilance Task with and without Search

1970 ◽  
Vol 12 (6) ◽  
pp. 537-545 ◽  
Author(s):  
W. Peter Colquhoun ◽  
Robert S. Edwards
Keyword(s):  
Detection Rate ◽  
Search Strategy ◽  
Vigilance Task ◽  
Substantial Improvement ◽  
The Other ◽  
Response Criterion ◽  
Practice Effects ◽  
Reference Standard ◽  
Group Search

Changes in performance at a visual vigilance task over eight 40-minute sessions were studied in three groups of eight subjects. The task was to inspect a series of displays of small disks for the occasional presence of a disk of slightly greater area than the others. For one group (search), each display consisted of a row of six disks. For one of the two no-search groups, the display contained two adjacent disks, one of which served as a reference standard; for the other group this reference disk was absent. Substantial improvement in overall detection rate occurred in all three groups. Analysis indicated that in each case this improvement was due to a genuine increase in discriminatory efficiency and not to any change in response criterion. Neither search nor the presence or absence of a reference standard appeared to affect the degree of improvement observed to any marked extent. Within-session decrement was observed only in the search group; this decrement was found to result from a change in response criterion, and not from any alteration either in discriminatory efficiency or search strategy.

Computer-Controlled Hrem Alignment Using Automated Diffractogram Analysis

1990 ◽  
Vol 48 (1) ◽  
pp. 532-533
Author(s):  
G.Y. Fan ◽  
O.L. Krivanek
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
The Other ◽  
Full Information ◽  
Resolution Electron ◽  
Skilled Operator ◽  
Automatic Alignment ◽  
High Resolution Electron Microscope ◽  
Computer Controlled ◽  
Recorded Image

Full alignment of a high resolution electron microscope (HREM) requires five parameters to be optimized: the illumination angle (beam tilt) x and y, defocus, and astigmatism magnitude and orientation. Because neither voltage nor current centering lead to the correct illumination angle, all the adjustments must be done on the basis of observing contrast changes in a recorded image. The full alignment can be carried out by a computer which is connected to a suitable image pick-up device and is able to control the microscope, sometimes with greater precision and speed than even a skilled operator can achieve. Two approaches to computer-controlled (automatic) alignment have been investigated. The first is based on measuring the dependence of the overall contrast in the image of a thin amorphous specimen on the relevant parameters, the other on measuring the image shift. Here we report on our progress in developing a new method, which makes use of the full information contained in a computed diffractogram.

scholarly journals Emotional Cognitive Regulation in University Students during Lockdown: A Comparative Analysis of Students from Spanish Universities

2021 ◽  
Vol 13 (12) ◽  
pp. 6946
Author(s):  
Mercedes Cuevas López ◽  
Inmaculada Ávalos Ruiz ◽  
Emilio Jesús Lizarte Simón
Keyword(s):  
Online Learning ◽  
University Students ◽  
Emotional Regulation ◽  
Adaptive Strategies ◽  
The Other ◽  
Housing Conditions ◽  
Gran Canaria ◽  
Self Blame ◽  
Cognitive Regulation ◽  
Spanish Universities

Studies focusing on strategies for the cognitive regulation of emotions are gaining importance due to the development and perpetuation of psychopathologies. The obligatory home confinement imposed in response to the COVID-19 pandemic has led to new virtual learning methodologies. Objective: Our objective aimed to analyze and compare the cognitive emotional regulation of students from universities on the Spanish mainland with that of students attending the Universidad de Las Palmas de Gran Canaria. Methods: An online Emotional Regulation Questionnaire was applied, together with a survey covering the students’ beliefs about the pandemic, including information about their housing conditions and beliefs about online learning. The study included a sample of 1030 university students. Results: On the mainland and at Las Palmas de Gran Canaria, the students most frequently used adaptive strategies. Three of the strategies were used in both groups but to different extents (Acceptance, Positive reappraisal, Putting into perspective), while the other strategies were used in both groups to the same extent (Refocusing on planning, Positive refocusing, Rumination, Blaming others, Catastrophizing, Self-blame). Meanwhile, the results were quite similar regarding the students’ housing conditions and beliefs about the pandemic and online learning.

Expressive Microstructure in Music: A Preliminary Perceptual Assessment of Four Composers' "Pulses"

1989 ◽  
Vol 6 (3) ◽  
pp. 243-273 ◽  
Author(s):  
Bruno H. Repp
Keyword(s):  
Classical Music ◽  
Random Order ◽  
Preliminary Test ◽  
The Other ◽  
Musical Experience ◽  
General Music ◽  
Cyclic Patterns ◽  
Computer Controlled ◽  
Perceptual Assessment ◽  
Essential Prerequisite

According to a provocative theory set forth by Manfred Clynes, there are composer-specific cyclic patterns of (unnotated) musical microstructure that, when discovered and realized by a performer, help to give the music its characteristic expressive quality. Clynes, relying mainly on his own judgment as an experienced musician, has derived such personal "pulses" for several famous composers by imposing time and amplitude perturbations on computer-controlled performances of classical music and modifying them until they converged on some optimal expression. To conduct a preliminary test of the general music lover's appreciation of such "pulsed" performances, two sets of piano pieces by Beethoven, Haydn, Mozart, and Schubert, one in quadruple and the other in triple meter, were selected for this study. Each piece was synthesized with each composer's pulse and also without any pulse. These different versions were presented in random order to listeners of varying musical sophistication for preference judgments relative to the unpulsed version. There were reliable changes in listeners' pulse preferences across different composers' pieces, which affirms one essential prerequisite of Clynes' theory. Moreover, in several instances the "correct" pulse was preferred most, which suggests not only that these pulse patterns indeed capture composer- specific qualities, but also that listeners without extensive musical experience can appreciate them. In other cases, however, listeners' preferences were not as expected, and possible causes for these deviations are discussed.

scholarly journals NHPP Software Reliability Model with Inflection Factor of the Fault Detection Rate Considering the Uncertainty of Software Operating Environments and Predictive Analysis

Symmetry ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 521 ◽  
Author(s):  
Song ◽  
Chang ◽  
Pham
Keyword(s):  
Fault Detection ◽  
Software Reliability ◽  
Detection Rate ◽  
The Other ◽  
Reliability Model ◽  
New Model ◽  
Software Failures ◽  
Software Failure ◽  
Software Reliability Model ◽  
Operating Environments

The non-homogeneous Poisson process (NHPP) software has a crucial role in computer systems. Furthermore, the software is used in various environments. It was developed and tested in a controlled environment, while real-world operating environments may be different. Accordingly, the uncertainty of the operating environment must be considered. Moreover, predicting software failures is commonly an important part of study, not only for software developers, but also for companies and research institutes. Software reliability model can measure and predict the number of software failures, software failure intervals, software reliability, and failure rates. In this paper, we propose a new model with an inflection factor of the fault detection rate function, considering the uncertainty of operating environments and analyzing how the predicted value of the proposed new model is different than the other models. We compare the proposed model with several existing NHPP software reliability models using real software failure datasets based on ten criteria. The results show that the proposed new model has significantly better goodness-of-fit and predictability than the other models.

DS-kNN

2021 ◽  
Vol 15 (2) ◽  
pp. 131-144
Author(s):  
Redha Taguelmimt ◽  
Rachid Beghdad
Keyword(s):  
Intrusion Detection ◽  
False Positive ◽  
Detection Rate ◽  
Nearest Neighbors ◽  
The Other ◽  
Intrusion Detection Systems ◽  
K Nearest Neighbors ◽  
Detection Systems ◽  
Knn Classifier ◽  
Better Than

On one hand, there are many proposed intrusion detection systems (IDSs) in the literature. On the other hand, many studies try to deduce the important features that can best detect attacks. This paper presents a new and an easy-to-implement approach to intrusion detection, named distance sum-based k-nearest neighbors (DS-kNN), which is an improved version of k-NN classifier. Given a data sample to classify, DS-kNN computes the distance sum of the k-nearest neighbors of the data sample in each of the possible classes of the dataset. Then, the data sample is assigned to the class having the smallest sum. The experimental results show that the DS-kNN classifier performs better than the original k-NN algorithm in terms of accuracy, detection rate, false positive, and attacks classification. The authors mainly compare DS-kNN to CANN, but also to SVM, S-NDAE, and DBN. The obtained results also show that the approach is very competitive.

scholarly journals Effects of relative frequency and delay interval of knowledge of results (KR) in the acquisition of motor skills

2006 ◽  
Vol 1 (1) ◽  
pp. 53-63
Author(s):  
Leandro R. Palhares ◽  
Alessandro T. Bruzi ◽  
Guilherme M. Lage ◽  
João V. A. P. Fialho ◽  
Herbert Ugrinowitsch ◽  
...  
Keyword(s):  
Motor Skills ◽  
Delay Interval ◽  
Motor Skill ◽  
Relative Frequency ◽  
The Other ◽  
Tennis Ball ◽  
Knowledge Of Results ◽  
Target Time ◽  
Serial Task

The purpose of the present study was to identify the effects of relative frequency and delay interval of Knowledge of Results (KR) in the acquisition of a serial motor skill. Sixty students were randomly distributed in 2 experiments, with three groups in each experiment (n = 10). The Experiment 1 investigated the effects of the KR frequency without KR delay interval and the Experiment 2 investigated the effects of the KR frequency with KR delay interval (3 seconds) in the acquisition of a serial motor skill. The serial task consisted of putting a tennis ball into six holes, positioned in a wood platform in a previously determined target time. In both experiments, the subjects performed 60 trials in target time of 2,700 ms, in the acquisition phase. In the Experiment 1, the results showed superiority of G33 in relation to the other groups, during the tests. In the Experiment 2, the results did not show any difference among the groups. These results are discussed with respect to the effect of KR delay interval, showing the role of combination of the variables.  

Sign in / Sign up

Export Citation Format

Share Document