• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 99
  • 14
  • 10
  • 9
  • 6
  • 2
  • 2
  • 1
  • Tagged with
  • 176
  • 176
  • 48
  • 37
  • 31
  • 31
  • 31
  • 30
  • 28
  • 26
  • 24
  • 22
  • 20
  • 19
  • 19
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Defining Display Complexity in Electric Utility System Operator Displays

McElhaney, Steven Hunt 14 December 2013 (has links)
In the electric utility industry, displays provide power system operators with information on and the status of the system, who then make decisions on how to maintain the safety, the reliability and the efficient operation of the utility generation and transmission grid based on that information. Complexity of the data presented and the display itself can lead to errors or misjudgments that can cause power system operators to make unwise decisions. The primary goal of this research was to develop a method to quantify display complexity for select displays used by system operators when operating the electric generation and transmission grids. Three studies were performed: (1) complexity measure development, (2) validation of the measure using usability and situation awareness (SA) techniques, and (3) display revisions based on complexity measure findings. Fifteen 15 different complexity metrics were originally considered (additive models, multiplicative models, and combination models with five different weighting schemes). The additive model with equal weighting was found to be the most sensitive in differentiating displays and was used in the later studies. For the validation study, system operators were asked to complete a usability questionnaire and a paper-based SA test using the current displays. Correlation and scatter plot analyses was used to determine if the complexity metric and usability and SA scores were related. Results of the validation study indicated that usability and SA scores for the studied displays were not well correlated with the complexity metric. In study 3, the highest and lowest scoring displays were redesigned with an emphasis on maintaining functionality but reducing aspects of complexity that were driving the complexity score. Systems operators again completed the usability and SA testing using the redesigned displays and again correlation analysis was performed. As was the case with study 2, usability scores were not correlated with the complexity metric; however, SA scores were significantly correlated. The complexity metric developed here can be used to quantify the complexity in a display and identify redesign opportunities to reduce non-essential information, as displays that are less complex should result in improved operator performance and satisfaction with the display.
2

Extended Situation Awareness Theory for Mobile Augmented Reality Interfaces to Support Navigation

Mi, Na 24 April 2014 (has links)
Despite the increasingly sophisticated capabilities of mobile AR guidance applications in providing new ways of interacting with the surrounding environment, empirical research remains needed in four principal areas: 1) identifying user needs and use cases, 2) developing an appropriate theoretical framework, 3) understanding user's interactions with the surrounding environment, and 4) avoiding information overload. To address these needs, a mixed-methods approach, involving two studies, was used to extend current Situation Awareness (SA) theory and evaluate the application of an extended theory. These were achieved in the context of a reality-augmented environment for the task of exploring an unfamiliar urban context. The first study examined SA in terms of the processes that an individual employs and the essential requirements needed to develop SA for the case of urban exploratory navigation using mobile augmented reality (MAR). From this study, SA-supported design implications for an MAR guidance application were developed, and used to evaluate the application of an extended SA theoretical cognitive model. The second study validated the earlier findings, and involved two specific applications of the translated SA-supported interface design and an evaluation of five conceptual design concepts. Results of the AR interface application suggested a significant SA-supported interface design effect on user's SA, which is dependent on the number of Points of Interest (POIs) included in the interface. Results of the embedded Map interface application showed a significant SA-support interface design effect on a user's SA. The SA-supported interface designs helped participants complete task queries faster and led to higher perceived interface usability. This work demonstrates that, by adopting a systematic approach, transformed requirements can be obtained and used to design and develop SA-supported strategies. In doing so, subsequent implementation of SA-supported strategies could enhance a user's SA in the context exploratory navigation in an urban environment using MAR. Indeed, a validation process was initiated for the extracted user requirements, by conducting evaluations on these SA-supported strategies. Finally, a set of preliminary design recommendations is proposed, with the goal of their eventual incorporation into the design and development of more effective mobile AR guidance applications. / Ph. D.
3

Adaptation and Validation of the Situation Awareness Global Assessment Technique for Student Registered Nurse Anesthetists

Dishman, Deniz 01 January 2019 (has links)
Anesthesia is a health care specialty fraught with high workload demands, stressful work environments, increased production pressure, work areas with many distractions, an increasing use of advanced technology, and the constant need to prioritize work actions. Effective clinical judgment in this dynamic environment necessitates that the provider demonstrate the ability to project what may occur secondary to actual or potential condition changes. These key elements operationalize situation awareness (SA). High level SA is an important characteristic for the successful development of student registered nurse anesthetists (SRNAs). With Endsley’s “Theory of Situation Awareness” as the foundation, the goal of this study was to adapt and validate the “Situation Awareness Global Assessment Technique” (SAGAT), to quantify SRNAs' SA during a specific simulated anesthesia event. With IRB approval, purposeful sampling identified a group of CRNA, nurse educator subjects and an exploratory sequential mixed methods design utilized. Delphi methods during qualitative data collection and validation used a seven-member sample. Content analysis resulted in items for the adapted SAGAT. Quantitative methods utilized data collected from a second 40-member sample yielding item content validity and scale content validity indices (S-CVI/Ave. 0.92). Additionally, exploratory factor analysis provided further reliability with a Cronbach’s alpha of 0.937. Findings revealed that a SAGAT specific to the anesthesia domain and the SRNA subgroup was amenable to adaptation and validation, providing positive implications in SRNA education and training. Additionally, results support the further adaptation, validation, and use of this instrument in other anesthetic content areas, as well as other health care domains.
4

Using Augmented Reality to Increase a Heavy Vehicle Operator's Situational Awareness

Päivärinne, Kim January 2018 (has links)
While operating a vehicle it is important to pay close attention to things such asdriving environment, other vehicles and your own vehicle. Developing a high level ofsituational awareness can be very beneficial for driving safety as it helps with makingdecisions.The purpose of this thesis is to investigate and explore how we can use augmentedreality to increase the situational awareness of a heavy vehicle operator. Our approachto solving this problem is to use the double diamond design method along with aliterary investigation in order to solve the correct problem, in the best way possible.For evaluation we did user testing and questionnaires to measure mental workloadand situational awareness. In this work we produced a prototype augmented realityapplication which we used in our tests. User feedback were almost entirely positive.
5

Understanding the Effects of Sleep Deprivation on Executive Function, Complex Task Performance and Situation Awareness

Grugle, Nancy Lynn 21 April 2005 (has links)
Both sleep deprivation and loss of situation awareness (SA) have been cited as primary causal factors contributing to the accident and injury rate in the military and civilian sector (e.g., transportation). Despite the numerous references to both factors as causal in nature, much of the literature on the effects of sleep deprivation on executive function is anecdotal. Research has produced mixed results regarding the nature and extent of performance degradation on a variety of lower-level and executive function tasks. Similarly, although SA has been cited as a significant contributor to operational performance, there is still considerable debate over the definition and construct validity of SA. Thus, a 29-hour hour sleep deprivation study was conducted to analyze the effects of sleep deprivation on both lower-order cognitive tasks (e.g., attention and working memory) and executive function tasks (e.g., reasoning, planning, decision making, and SA). In conjunction with the sleep deprivation analysis, the relationships among lower level cognition, executive function, and situation awareness were analyzed to form hypotheses about the SA construct and its relationship to complex task performance. Forty-eight participants were administered a series of cognitive tasks during baseline and sleep deprived testing sessions. Paired t-tests and additional post hoc analyses were conducted to determine the effects of sleep deprivation on cognition. Regression and factor analysis were used analyze the relationship among lower-order cognition, executive function, situation awareness, and complex task performance. Paired t-test results showed degraded vigilance in response to sleep deprivation, but did not indicate degraded executive function. Results of additional post-hoc analyses on executive function data indicated a trend toward degraded decision making and a trend toward increased planning errors in response to sleep deprivation. The results of the regression and factor analyses provided initial support for a dynamic, process definition of SA and illustrated the importance of considering SA as part of information processing as a whole in order to improve performance prediction. Based on the results of this dissertation, engineering recommendations were made for developing an "ideal" SA measurement technique and improving existing SA measurement techniques. Additionally, future sleep deprivation and situation awareness research directions were suggested. / Ph. D.
6

The Effects of Cognitive Executive Load on Driving Crashes and Near-Crashes

Sullivan, Keith Alexander 08 June 2022 (has links)
Previous naturalistic driving studies have shown that visual and manual secondary tasks increase driving crash risk. With the increasing use of infotainment systems in vehicles, secondary tasks requiring cognitive executive demand may increase crash risk, especially for young and older drivers. Naturalistic driving data were examined to determine if secondary tasks with increasing cognitive executive demand would result in increasing crash risk. Data were extracted from the Second Strategic Highway Research Program Naturalistic Driving Study, where vehicles were instrumented to record driving behavior and crash/near-crash data. Cognitive executive and visual-manual tasks paired with a second cognitive executive task were compared to the cognitive executive and visual-manual tasks performed alone. Crash/near-crash odds ratios were computed by comparing each task condition to driving without presence of any secondary task. Dual cognitive executive tasks resulted in greater odds ratios than those for single cognitive executive tasks. The dual visual-manual tasks odds ratios did not increase from single task odds ratios. These effects were only found for young drivers. These findings help validate that cognitive executive secondary task load increases crash/near-crash risk, especially in dual task situations for young drivers. Future research should be conducted to minimize cognitive task load associated with vehicle infotainment systems using such technologies as voice commands. / Master of Science / Previous naturalistic driving studies have shown that visual and manual secondary tasks increase driving crash risk. With the increasing use of infotainment systems in vehicles, secondary tasks requiring cognitive demand may increase crash risk, especially for young and older drivers. Naturalistic driving study data were examined to determine if secondary tasks with increasing proposed cognitive demand would result in increasing crash/near-crash risk. Cognitive and visual-manual tasks paired with a second cognitive task were compared to the cognitive and visual-manual tasks performed alone. It was found that dual cognitive tasks resulted in greater crash/near-crash risk than the single cognitive executive tasks. The dual visual-manual tasks did not show greater crash/near crash risk than the visual-manual tasks performed alone. These effects were only found for young drivers. These findings help validate that cognitive secondary task load increases crash/near-crash risk, especially in dual task situations for young drivers. Future infotainment systems and drivers' education programs should be designed to minimize cognitive loads.
7

Compréhension dynamique du contexte pour l'aide à l'opérateur en robotique / Dynamic understanding the context for helping operator in robotics

Ben Ghezala, Mohamed Walid 21 July 2015 (has links)
Les technologies de l'informatique et de la robotique sont en perpétuelle évolution. S'appuyant sur cette évolution technologique, les systèmes d’aide à l’opérateur restent un domaine de recherche d’actualité. Le principal défi des systèmes de la future génération est d'être "intelligents", sensibles au contexte dans un environnement complexe et imprévisible. Cette thèse entre dans ce cadre et traite de la compréhension dynamique du contexte par un robot évoluant dans un tel environnement. En particulier, elle s'intéresse à la question suivante: comment rendre un robot capable de réagir face aux situations de blocage, imprévues dans son plan d’action initial, pour accomplir l’objectif fixé par l’opérateur ? Dans la littérature, ce problème a été soulevé et résolu en partie en programmant dans le système robotique, certaines des fonctions rendant le robot plus autonome. Cependant, l'intégration de ces fonctions dans un même cadre est manquante et plusieurs recherches dans ce sens sont en cours. Dans nos travaux nous proposons un système supportant une approche complète et générique, qui assure à un robot la capacité d’être conscient de la situation de blocage dans laquelle il se trouve et de comprendre et faire face aux situations de blocage rencontrées. Notre approche, nommée Robot Situation AWareness (RSAW) est inspirée de la notion de Situation Awareness (SA) qui a fait ses preuves dans de nombreux domaines notamment dans l’aviation. Nos principales contributions dans RSAW portent sur la conception d’un cadre sémantique intégrant la capacité de compréhension, fondé sur une représentation des connaissances générique, donnant la possibilité d’appliquer des techniques de raisonnement empruntées aux sciences cognitives. L’intégration de RSAW dans un système robotique a également été étudiée, conçue et mise en œuvre dans un système à couches. Ce système d'expérimentation est le robot SAM (Smart Autonomous Majordomo) doté du système AVISO et développé par le CEA-LIST. Les résultats des expérimentations élaborées dans le cadre des travaux menés dans cette thèse sont concluants et prometteurs / Computer technology and robotics are in perpetual evolution. Based on this technological evolution, the operator support systems remain a topical domain of research. The main challenge for the next generation of systems is to be "intelligent", aware of the context in a complex and unpredictable environment. This thesis is into this framework and addresses the dynamic understanding of the context by a robot evolving in such an environment. In particular, the work is interested in the question: How to make a robot able to react to blocked situations unplanned in its initial action plan to achieve the goal set by the operator?In the literature, this issue was raised and resolved in part by programming in robotic system, some of the features making a robot more autonomous. However, the integration of these functions in one framework is missing and more research in this direction is underway. In our work we propose a system supporting a complete and generic approach that ensures a robot the ability to be aware of the blocking situation in which it is found, to understand and deal with deadlock situations encountered. Our approach, called Robot Situation Awareness (RSAW) is inspired by the notion of Situation Awareness (SA), which has been proven in many areas especially in aviation. Our main contributions in RSAW involve the design of a semantic framework integrating the understanding capacity, based on a generic representation of knowledge and giving the possibility to apply reasoning techniques borrowed from cognitive science. Integrating RSAW in a robotic system has also been studied, designed and implemented in a layer system. This experimental system is the robot SAM (Smart Autonomous Majordomo) with the AVISO system developed by CEA-LIST. The conducted experiments allowed testing of the deductive reasoning in resolving a blocked situation and confirmed the need to resort to analogical reasoning. Another wave of experimentation has taken place to prove the effectiveness of our choices. The results of experiments developed as part of the work in this thesis are successful and promising
8

Evaluating Situation Awareness Oriented
 Design Principles as a Design Tool / Att Utvärdera Situation Awareness-Orienterade Designprinciper Som Designverktyg

Pesavento, Luca January 2015 (has links)
In critical scenarios such as power plant management or air traffic control, human errors can have critical consequences. It is therefore a key concern that operators have a clear understanding of the situation at hand. Providing high situation awareness when designing interactive systems for these users is an important concern: many factors need to be considered to avoid hazardous conditions. Situation Awareness Oriented Design (SAOD) is a design methodology that makes use of design principles as tools to guide designers in creating or adapting systems for achieving outstanding situation awareness. This study focuses on what problems arise when using a selection of SAOD principles as the principal tool in the design process. The research was carried out using a research-through- design methodology, where SAOD principles were employed for the design of D4SH, an interactive overview system in the maritime scope of remote service centres. The results indicate four problems that might occur in the design process by using these principles. First, principles did not help in making design decisions. Second, at times they indirectly conflicted with one another when having to make a choice. Third, grounded user analysis was needed for the correct use of the principles. Fourth, in some instances principles highlighted a problem without offering a desirable solution. Therefore, the validity of principles in the various phases of design is questioned, and some implications of using the principles as a complementary design tool are suggested. In conclusion, it is argued that the problems encountered are a necessary trade-off for having a powerful framework that can be successfully used in many contexts for situation awareness. / I kritiska situationer, såsom kraftverkshantering eller flyplansledning, kan mänskliga fel ha allvarliga konsekvenser. Det är därför viktigt att tekniska operatörer har en god uppfattning av den aktuella situationen. En nyckelfråga då interaktiva system för dessa användare designas är därför att tillhandahålla en hög situationsmedvetenhet, där många faktorer beaktas för att undvika farliga situationer. Situation Awareness Oriented Design (SAOD) är en metodik som använder designprinciper som vägledning då system anpassas för att tillhandahålla god situationsmedvetenhet. I denna studie undersöks vilka problem som uppstår när man använder ett urval av SAOD-principer som det främsta verktyget i designprocessen. Forskningen genomfördes med hjälp av en designmetodik där SAOD-principer användes för att utforma D4SH, ett interaktivt översiktsystem för servicecenter inom den marina sektorn. Studiens resultat indikerar fyra problem som kan uppstå genom att använda dessa principer i en designprocess. Först och främst upplevdes principerna inte underlätta designbeslut. För det andra var principerna indirekt motsägelsefulla då ett beslut skulle fattas. För det tredje behövdes en grundläggande användaranalys för att använda principerna korrekt. För det fjärde belyste principerna i vissa lägen problem utan att erbjuda en önskvärd lösning. Baserat på detta ifrågasätts principernas giltighet och konsekvenser av att använda principerna som ett kompletterande designverktyg föreslås. Slutsatsen av studien hävdar att problemen som identifieras är en nödvändig kompromiss för att kunna erbjuda en kraftfull ram, som framgångsrikt kan användas i många sammanhang för att tillhandahålla situationsmedvetenhet.
9

Development of Shared Situation Awareness Guidelines and Metrics as Developmental and Analytical Tools for Augmented and Virtual Reality User Interface Design in Human-Machine Teams

Van Dam, Jared Martindale Mccolskey 21 August 2023 (has links)
As the frontiers and futures of work evolve, humans and machines will begin to share a more cooperative working space where collaboration occurs freely amongst the constituent members. To this end, it is then necessary to determine how information should flow amongst team members to allow for the efficient sharing and accurate interpretation of information between humans and machines. Shared situation awareness (SSA), the degree to which individuals can access and interpret information from sources other than themselves, is a useful framework from which to build design guidelines for the aforementioned information exchange. In this work, we present initial Augmented/virtual reality (AR/VR) design principles for shared situation awareness that can help designers both (1) design efficacious interfaces based on these fundamental principles, and (2) evaluate the effectiveness of candidate interface designs based on measurement tools we created via a scoping literature review. This work achieves these goals with focused studies that 1) show the importance of SSA in augmented reality-supported tasks, 2) describe design guidelines and measurement tools necessary to support SSA, and 3) validate the guidelines and measurement tools with a targeted user study that employs an SSA-derived AR interface to confirm the guidelines distilled from the literature review. / Doctor of Philosophy / As the way in which humans work and play changes, people and machines will need to work together in shared spaces where team members rely on one another to complete goals. To make this interaction happen in ways that benefit both humans and machines, we will need to figure out the best way for information to flow between team members, including both humans and machines. Shared situation awareness (SSA) is a helpful concept that allows us to understand how people can get and understand information from sources other than themselves. In this research, we present some basic ideas for designing augmented reality (AR) tools that help people work together in better ways using SSA as a guiding framework. These ideas can help designers (1) create AR tools that work well based on these basic ideas and (2) test how well different interface designs work using specially developed tools we made. We completed user studies to (1) show how important SSA is when using AR to help with tasks, (2) explain the design ideas and tools needed to support SSA, and (3) test these ideas and tools with a study that uses an AR tool, based on SSA, to make sure the guidelines we got from reading other research are correct.
10

The making of D-SAT: the development and testing of Dynamic Situation Awareness Task

Woller, Margo M. January 1900 (has links)
Master of Science / Department of Psychology / James C. Shanteau / Situation Awareness (SA) measurement takes on many forms: subjective, direct, and implicit performance, each with limitations. Subjective measures are based on self and peer reports, which allow biases to enter the measurement. Direct measures, such as SA Global Assessment Technique (SAGAT), interrupt SA in order to probe the participants’ SA level using questions. Implicit performance measures are based on participants’ ability to complete SA tasks, which must be created for each domain. A new approach, Dynamic – SA Task (D-SAT), was developed using a microworld wildfire fighting simulation, Networked Fire Chief (NFC). D-SAT is an implicit performance measure that can be adapted to multiple domains, for example inattentional blindness. Scenarios were developed during study one by tracking participant performance and scenario situations. Study two used the scenarios developed during study one to test D-SAT’s ability to evaluate SA by comparing D-SAT performance to an established SA performance measure, situation awareness global assessment technique (SAGAT). While the manipulation used to create had an effect on D-SAT performance, it was not associated with the established SA performance measure. However, a signal detection theory (SDT) analysis showed additional promise for D-SAT being a useful SA measure.

Page generated in 0.1364 seconds