Situation Awareness Adaptive Alerting in an Aircraft Cockpit: A Simulator Study

The goal of this study was to develop an automated cockpit support system that is adaptive to the flight crew’s situation awareness (SA) estimated by online gaze analysis. Flight crew errors are often attributed to low SA. Online measurement of SA could be used to automatically guide the user’s attention for the sake of fewer errors and better performance.An eye-tracking based measure for SA was developed and used for the adaptive generation of alerts in a flight simulator. In an experiment, ten certified pilots conducted two trials with no and adaptive alerting. The experimental task involved tracking of flight parameters which were partially disturbed or changed at random times. Our online estimation of SA showed a strong correlation with observed pilot performance. With adaptive alerts, the average performance increased in those experimental tasks, where a situational change could not be predicted by participants. Also, adaptive alerts improved change detection and reduced the number of outliers, where a change was not noticed for an exceptionally long time. However, subjective rating was poor due to low transparency and false positives. SA-adaptive support can improve change detection performance in typical tasks on the flight deck. For a greater acceptance, pilots should be trained to understand the adaption policy.

Does perceptual grouping improve visuospatial working memory? Optimized processing or encoding bias

Visual working memory has been defined as a system of limited capacity that enables the maintenance and manipulation of visual information. However, some perceptual features like Gestalt grouping could improve visual working memory effectiveness. In two different experiments, we aimed to explore how the presence of elements grouped by color similarity affects the change detection performance of both, grouped and non-grouped items. We combined a change detection task with a retrocue paradigm in which a six item array had to be remembered. An always valid, variable-delay retrocue appeared in some trials during the retention interval, either after 100 ms (iconic-trace period) or 1400 ms (working memory period), signaling the location of the probe. The results indicated that similarity grouping biased the information entered into the visual working memory, improving change detection accuracy only for previously grouped probes, but hindering change detection for non-grouped probes in certain conditions (Exp. 1). However, this bottom-up automatic encoding bias was overridden when participants were explicitly instructed to ignore grouped items as they were irrelevant for the task (Exp. 2).

Preparing for the Worst: Attention is Enhanced Prior to Any Upcoming Emotional or Neutral Stimulus

Do people allocate more or fewer attentional resources when preparing for negative emotional visual stimuli to appear? In three experiments (total N = 150), participants performed a change-detection task while expecting a neutral, threatening, disgusting, or joyful stimulus or no stimulus to appear at a fixed moment. Responses to an infrequent dot probe were faster when participants were expecting a distracting stimulus. Importantly, although only negative stimuli impaired change-detection performance, there was no difference between the preparation effect for threatening and neutral stimuli (Experiment 1) or disgusting and joyful stimuli (Experiment 3). The preparation effects were also unaffected by the participant’s anxiety level. Experiment 2 confirmed that the threatening images affected performance when the dot probe appeared after the image. These results suggest that the visual system increases alertness in response to any upcoming stimulus and further imply that the effects of emotional stimuli largely occur after, but not before, the stimuli appear.

A Novel Metal Foreign Object Detection for Wireless High-Power Transfer Using a Two-Layer Balanced Coil Array with a Serial-Resonance Maxwell Bridge

In a wireless high-power transfer system with a distance of several tens of centimeters apart between the transmitter and receiver coils, one of the most challenging issues is to detect metallic foreign objects between the transmitter and receiver coils. The metallic foreign objects must be detected and removed since these reduce the transmission efficiency and cause heat generation of the transmitter and receiver. This paper presents two-layer symmetric balanced coil array so that if there are metallic foreign objects, it can be detected through the change of the inductance of the balanced coils. Since the balanced coil is composed of coils that are in a symmetrical relationship in position, there is no need for a reference coil, and interference between coils is reduced by dividing the coil into two layers. In addition, a novel serial-resonance Maxwell bridge circuit to improve the inductance change detection performance is presented in this paper. The proposed metallic foreign object detection system is implemented using two-layer balanced coil array with a serial-resonance Maxwell bridge and the experimental results show that voltage changes of hundreds of mV to several V occur when a metallic foreign object is inserted, so that even small metals such as clips can be detected.

The effect of healthy aging on change detection and sensitivity to predictable sturcture in crowded acoustic scenes

The auditory system plays a critical role in supporting our ability to detect abrupt changes in our surroundings. Here we study how this capacity is affected in the course of healthy ageing. Artifical acoustic ‘scenes’, populated by multiple concurrent streams of pure tones (‘sources’) were used to capture the challenges of listening in complex acoustic environments. Two scene conditions were included: REG scenes consisted of sources characterized by a regular temporal structure. Matched RAND scenes contained sources which were temporally random. Changes, manifested as the abrupt disappearance of one of the sources, were introduced to a subset of the trials and participants (‘young’ group N=41, age 20-38 years; ‘older’ group N=41, age 60-82 years) were instructed to monitor the scenes for these events. Previous work demonstrated that young listeners exhibit better change detection performance in REG scenes, reflecting sensitivity to temporal structure. Here we sought to determine: (1) Whether ‘baseline’ change detection ability (i.e. in RAND scenes) is affected by age. (2) Whether aging affects listeners’ sensitivity to temporal regularity. (3) How change detection capacity relates to listeners’ hearing and cognitive profile. The results demonstrated that healthy aging is associated with reduced sensitivity to abrupt scene changes in RAND scenes but that performance does not correlate with age or standard audiological measures such as pure tone audiometry or speech in noise performance. Remarkably older listeners’ change detection performance improved substantially (up to the level exhibited by young listeners) in REG relative to RAND scenes. This suggests that the capacity to extract and track the regularity associated with scene sources, even in crowded acoustic environments, is relatively preserved in older listeners.

FULL POLARIMETRIC UAVSAR IMAGE CHANGE DETECTION BASED ON CHANGE INDICES

Change detection is one of the most important applications of Polarimetric Synthetic Aperture Radar (PolSAR) data in monitoring urban development and supporting urban planning due to the sensibility of SAR signal to geometrical and physical properties of terrestrial features. In this paper, we proposed an unsupervised change detection method using change indices extracted from PolSAR images. Kernel k-means clustering was then performed to extract changed areas. The kernel k-means clustering is an unsupervised algorithm that maps the input features to higher Hilbert dimension space by using a kernel function. To better representation of changed areas, different change indices were generated. The method was applied to UAVSAR L-band SAR images acquired over an urban area in San Andreas, United States. We evaluated the change detection performance based on kappa and overall accuracies of the proposed approach and compared with other well-known classic methods.

Performance of Change Detection Algorithms Using Heterogeneous Images and Extended Multi-attribute Profiles (EMAPs)

We present detection performance of ten change detection algorithms with and without the use of Extended Multi-Attribute Profiles (EMAPs). Heterogeneous image pairs (also known as multimodal image pairs), which are acquired by different imagers, are used as the pre-event and post-event images in the investigations. The objective of this work is to examine if the use of EMAP, which generates synthetic bands, can improve the detection performances of these change detection algorithms. Extensive experiments using five heterogeneous image pairs and ten change detection algorithms were carried out. It was observed that in 34 out of 50 cases, change detection performance was improved with EMAP. A consistent detection performance boost in all five datasets was observed with EMAP for Homogeneous Pixel Transformation (HPT), Chronochrome (CC), and Covariance Equalization (CE) change detection algorithms.

The match in orientation between verbal context and object accelerates change detection

Research in the field of embodied cognition has shown that sensorimotor simulation significantly influences various aspects of cognitive processing. This experiment was designed to test the impact of the sensorimotor simulation of objects? physical proprieties, initiated by the preceding verbal context, on change detection performance. Before performing each of change detection trials, participants were exposed to sentences suggesting a particular object orientation (horizontal or vertical). The orientation in the first display of the objects that were to be replaced in the second was also manipulated. Response latencies results show that the sentences implying the same spatial orientation as that of the to-be-changed object led to a faster detection of its change compared to the sentences that implied the mismatching orientation, an effect that we explain in terms of the superior encoding, facilitated by sensorimotor simulation, of the objects with matching orientation.