Pirate stealth or inattentional blindness?:the effects of target relevance and sustained attention on security monitoring for experienced and naïve operators

Closed Circuit Television (CCTV) operators are responsible for maintaining security in various applied settings. However, research has largely ignored human factors that may contribute to CCTV operator error. One important source of error is inattentional blindness--the failure to detect unexpected but clearly visible stimuli when attending to a scene. We compared inattentional blindness rates for experienced (84 infantry personnel) and naïve (87 civilians) operators in a CCTV monitoring task. The task-relevance of the unexpected stimulus and the length of the monitoring period were manipulated between participants. Inattentional blindness rates were measured using typical post-event questionnaires, and participants' real-time descriptions of the monitored event. Based on the post-event measure, 66% of the participants failed to detect salient, ongoing stimuli appearing in the spatial field of their attentional focus. The unexpected task-irrelevant stimulus was significantly more likely to go undetected (79%) than the unexpected task-relevant stimulus (55%). Prior task experience did not inoculate operators against inattentional blindness effects. Participants' real-time descriptions revealed similar patterns, ruling out inattentional amnesia accounts

Visuo-spatial Abilities In Remote Perception: A Meta-analysis Of Empirical Work

Meta-analysis was used to investigate the relationship between visuo-spatial ability and performance in remote environments. In order to be included, each study needed to examine the relationship between the use of an ego-centric perspective and various dimensions of performance (i.e., identification, localization, navigation, and mission completion time). The moderator analysis investigated relationships involving: (a) visuo-spatial construct with an emphasis on Carroll’s (1993) visualization (VZ) factor; (b) performance outcome (i.e., identification, localization, navigation, and mission completion time); (c) autonomy to support mission performance; (d) task type (i.e., navigation vs. reconnaissance); and (e) experimental testbed (i.e., physical vs. virtual environments). The process of searching and screening for published and unpublished analyses identified 81 works of interest that were found to represent 50 unique datasets. 518 effects were extracted from these datasets for analyses. Analyses of aggregated effects (Hunter & Schmidt, 2004) found that visuo-spatial abilities were significantly associated with each construct, such that effect sizes ranged from weak (r = .235) to moderately strong (r = .371). For meta-regression (Borenstein, Hedges, Figgins, & Rothstein, 2009; Kalaian & Raudenbush, 1996; Tabachnick & Fidell, 2007), moderation by visuo-spatial construct (i.e., focusing on visualization) was consistently supported for all outcomes. For at least one of the outcomes, support was found for moderation by test, the reliability coefficient of a test, autonomy (i.e. to support identification, localization, and navigation), testbed (i.e., physical vs. virtual environment), intended domain of application, and gender. These findings illustrate that majority of what researchers refer to as “spatial ability” actually uses measures that load onto Carroll’s (1993) visualization (VZ) factor. The associations between this predictor and all performance outcomes were significant, but the significant iv variation across moderators highlight important issues for the design of unmanned systems and the external validity of findings across domains. For example, higher levels of autonomy for supporting navigation decreased the association between visualization (VZ) and performance. In contrast, higher levels of autonomy for supporting identification and localization increased the association between visualization (VZ) and performance. Furthermore, moderation by testbed, intended domain of application, and gender challenged the degree to which findings can be expected to generalize across domains and sets of participants

A design ideation method for novice designers

Design ideation is a core stage in the design process that begins with a design brief and results in a range of design concepts from which solutions can be selected. The success of design ideation relies upon designers’ creativity and ingenuity. In current practice, design ideation tends to be an ad hoc process which combines the designer’s experience with techniques such as sketching, brainstorming, and mock-up to develop creative solutions in response to the brief. There are notable differences in ideation performance between novice and expert designers in that experts tend to follow a more systematic process, and have more experience and knowledge of previous designs to draw on. Design ideation is more challenging for novice designers who have limited experience on which to draw and no systematic process to follow. This thesis provides a method that enhances the design ideation performance of novice designers by providing a systematic design ideation process for them to follow, and a database and associated visualisation method that gives them access to previous designs. The method was assessed through empirical evaluation experiments conducted with 101 students in the UK and South Korea. This confirmed that the method improves novice designers’ generation of creative solution concepts in response to a design brief. The research makes four contributions. The method, Knowledge-Enabled Design Ideation Method (KEDIM), provides a systematic design ideation process that includes three steps. The first step draws on a Database of Design Cases (DOS) that is supported by a database schema. DOS is a part of the research contribution that provides a structure to capture case data. DOS was validated through population with 540 design cases, and through use in the second stage of KEDIM, Perceptual Mapping Generation Software (PMGS). The core contribution of PMGS is its visualisation method that brings together selected design cases from the database and presents them in a way that enhances novice designers’ abilities to draw analogies. The final contribution is Systematic Brainstorming (SBI), where these analogies are developed through a set of specific ideation themes alongside solution concepts. KEDIM, through these three tools, improves the effectiveness of novice designers ideation by increasing the number of solution concepts generated when compared with students not using KEDIM responding to the same brief

Change blindness: eradication of gestalt strategies

Arrays of eight, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB) task where there was a 50% chance that one rectangle would change orientation between two successive presentations separated by an interval. CB was eliminated by cueing the target rectangle in the first stimulus, reduced by cueing in the interval and unaffected by cueing in the second presentation. This supports the idea that a representation was formed that persisted through the interval before being 'overwritten' by the second presentation (Landman et al, 2003 Vision Research 43149–164]. Another possibility is that participants used some kind of grouping or Gestalt strategy. To test this we changed the spatial position of the rectangles in the second presentation by shifting them along imaginary spokes (by ±1 degree) emanating from the central fixation point. There was no significant difference seen in performance between this and the standard task [F(1,4)=2.565, p=0.185]. This may suggest two things: (i) Gestalt grouping is not used as a strategy in these tasks, and (ii) it gives further weight to the argument that objects may be stored and retrieved from a pre-attentional store during this task

Contrast Dependent Knowledge Development in Contrast Supported Scientific Observation

Knowledge of contrasts between phenomena can influence how people think and reason about them, so learning contrasts is important in school science. Building knowledge through a process of construction is a common framework through which school science is taught. However, telling phenomena apart through differentiation also plays an important role in learning and may be underused as a teaching framework. An effective way to learn contrasts is to use them to perceptually differentiate similar-looking phenomena presented side-by-side. However, little is known about the persistence/usefulness of knowledge generated during perceptual differentiation over short periods of time and its usage in student reasoning within an argument. This study addresses this issue through the use of a sample “ID activity” in which participants are shown a side-by-side presentation of two species and asked to identify them using two sets of contrasts. Student thinking was monitored through the collection of 10 student think-alouds. Results show that once a contrast statement is made it is repeated. These initial observations and repeats coalesce to form the students contrast dependent knowledge of the species. This shows that not only is perceptual knowledge persistent over long periods time, as established in previous studies, but it persists within a short activity. Furthermore, in most instances the restatements are used as a part of rebuttal within an argument. Understanding the nature of knowledge gained from contrast-supported scientific observation has implications for the usage of contrast activities in school science

An analysis of the relationship between city typology, interactivity and advertising message strategies of American municipal web sites

This study became to first to scientifically explore the relationship between city typology and the use of advertising message strategy and interactivity within municipal web sites. The study used Taylor’s six-segment strategy wheel to analyze message strategies and previous scales of interactivity to analyze structural interactivity. Medium-size cities and cities within the South and West geographic regions more likely used sensory strategies within their web sites. Cities with racially diverse populations more likely used sensory strategies within their web sites as well. Large cities and central cities, both with large populations, used the most interactive strategies within their sites compared to their respective classifications. Cities within the mountain geographic division used the most interactive features among geographic locations and more racially diverse cities used more interactive features than predominantly Caucasian or minority populations. Thus, both message strategy and interactivity proved to share relationships with city typology

A Hybrid Visual Control Scheme to Assist the Visually Impaired with Guided Reaching Tasks

In recent years, numerous researchers have been working towards adapting technology developed for robotic control to use in the creation of high-technology assistive devices for the visually impaired. These types of devices have been proven to help visually impaired people live with a greater degree of confidence and independence. However, most prior work has focused primarily on a single problem from mobile robotics, namely navigation in an unknown environment. In this work we address the issue of the design and performance of an assistive device application to aid the visually-impaired with a guided reaching task. The device follows an eye-in-hand, IBLM visual servoing configuration with a single camera and vibrotactile feedback to the user to direct guided tracking during the reaching task. We present a model for the system that employs a hybrid control scheme based on a Discrete Event System (DES) approach. This approach avoids significant problems inherent in the competing classical control or conventional visual servoing models for upper limb movement found in the literature. The proposed hybrid model parameterizes the partitioning of the image state-space that produces a variable size targeting window for compensatory tracking in the reaching task. The partitioning is created through the positioning of hypersurface boundaries within the state space, which when crossed trigger events that cause DES-controller state transition that enable differing control laws. A set of metrics encompassing, accuracy ($D$), precision ($\theta_{e}$), and overall tracking performance ($\psi$) are also proposed to quantity system performance so that the effect of parameter variations and alternate controller configurations can be compared. To this end, a prototype called \texttt{aiReach} was constructed and experiments were conducted testing the functional use of the system and other supporting aspects of the system behaviour using participant volunteers. Results are presented validating the system design and demonstrating effective use of a two parameter partitioning scheme that utilizes a targeting window with additional hysteresis region to filtering perturbations due to natural proprioceptive limitations for precise control of upper limb movement. Results from the experiments show that accuracy performance increased with the use of the dual parameter hysteresis target window model ($0.91 \leq D \leq 1$, $\mu(D)=0.9644$, $\sigma(D)=0.0172$) over the single parameter fixed window model ($0.82 \leq D \leq 0.98$, $\mu(D)=0.9205$, $\sigma(D)=0.0297$) while the precision metric, $\theta_{e}$, remained relatively unchanged. In addition, the overall tracking performance metric produces scores which correctly rank the performance of the guided reaching tasks form most difficult to easiest