Guidelines for developing distributed virtual environment applications

NASA Astrophysics Data System (ADS)

Stytz, Martin R.; Banks, Sheila B.

1998-08-01

We have conducted a variety of projects that served to investigate the limits of virtual environments and distributed virtual environment (DVE) technology for the military and medical professions. The projects include an application that allows the user to interactively explore a high-fidelity, dynamic scale model of the Solar System and a high-fidelity, photorealistic, rapidly reconfigurable aircraft simulator. Additional projects are a project for observing, analyzing, and understanding the activity in a military distributed virtual environment, a project to develop a distributed threat simulator for training Air Force pilots, a virtual spaceplane to determine user interface requirements for a planned military spaceplane system, and an automated wingman for use in supplementing or replacing human-controlled systems in a DVE. The last two projects are a virtual environment user interface framework; and a project for training hospital emergency department personnel. In the process of designing and assembling the DVE applications in support of these projects, we have developed rules of thumb and insights into assembling DVE applications and the environment itself. In this paper, we open with a brief review of the applications that were the source for our insights and then present the lessons learned as a result of these projects. The lessons we have learned fall primarily into five areas. These areas are requirements development, software architecture, human-computer interaction, graphical database modeling, and construction of computer-generated forces.

Objective Fidelity Evaluation in Multisensory Virtual Environments: Auditory Cue Fidelity in Flight Simulation

PubMed Central

Meyer, Georg F.; Wong, Li Ting; Timson, Emma; Perfect, Philip; White, Mark D.

2012-01-01

We argue that objective fidelity evaluation of virtual environments, such as flight simulation, should be human-performance-centred and task-specific rather than measure the match between simulation and physical reality. We show how principled experimental paradigms and behavioural models to quantify human performance in simulated environments that have emerged from research in multisensory perception provide a framework for the objective evaluation of the contribution of individual cues to human performance measures of fidelity. We present three examples in a flight simulation environment as a case study: Experiment 1: Detection and categorisation of auditory and kinematic motion cues; Experiment 2: Performance evaluation in a target-tracking task; Experiment 3: Transferrable learning of auditory motion cues. We show how the contribution of individual cues to human performance can be robustly evaluated for each task and that the contribution is highly task dependent. The same auditory cues that can be discriminated and are optimally integrated in experiment 1, do not contribute to target-tracking performance in an in-flight refuelling simulation without training, experiment 2. In experiment 3, however, we demonstrate that the auditory cue leads to significant, transferrable, performance improvements with training. We conclude that objective fidelity evaluation requires a task-specific analysis of the contribution of individual cues. PMID:22957068

Feasibility of training athletes for high-pressure situations using virtual reality.

PubMed

Stinson, Cheryl; Bowman, Doug A

2014-04-01

Virtual reality (VR) has been successfully applied to a broad range of training domains; however, to date there is little research investigating its benefits for sport psychology training. We hypothesized that using high-fidelity VR systems to display realistic 3D sport environments could trigger anxiety, allowing resilience-training systems to prepare athletes for real-world, highpressure situations. In this work we investigated the feasibility and usefulness of using VR for sport psychology training. We developed a virtual soccer goalkeeping application for the Virginia Tech Visionarium VisCube (a CAVE-like display system), in which users defend against simulated penalty kicks using their own bodies. Using the application, we ran a controlled, within-subjects experiment with three independent variables: known anxiety triggers, field of regard, and simulation fidelity. The results demonstrate that a VR sport-oriented system can induce increased anxiety (physiological and subjective measures) compared to a baseline condition. There were a number of main effects and interaction effects for all three independent variables in terms of the subjective measures of anxiety. Both known anxiety triggers and simulation fidelity had a direct relationship to anxiety, while field of regard had an inverse relationship. Overall, the results demonstrate great potential for VR sport psychology training systems; however, further research is needed to determine if training in a VR environment can lead to long-term reduction in sport-induced anxiety.

Learning Intercultural Communication Skills with Virtual Humans: Feedback and Fidelity

ERIC Educational Resources Information Center

Lane, H. Chad; Hays, Matthew Jensen; Core, Mark G.; Auerbach, Daniel

2013-01-01

In the context of practicing intercultural communication skills, we investigated the role of fidelity in a game-based, virtual learning environment as well as the role of feedback delivered by an intelligent tutoring system. In 2 experiments, we compared variations on the game interface, use of the tutoring system, and the form of the feedback.…

See one, do one, teach one: advanced technology in medical education.

PubMed

Vozenilek, John; Huff, J Stephen; Reznek, Martin; Gordon, James A

2004-11-01

The concept of "learning by doing" has become less acceptable, particularly when invasive procedures and high-risk care are required. Restrictions on medical educators have prompted them to seek alternative methods to teach medical knowledge and gain procedural experience. Fortunately, the last decade has seen an explosion of the number of tools available to enhance medical education: web-based education, virtual reality, and high fidelity patient simulation. This paper presents some of the consensus statements in regard to these tools agreed upon by members of the Educational Technology Section of the 2004 AEM Consensus Conference for Informatics and Technology in Emergency Department Health Care, held in Orlando, Florida. Web-based teaching: 1) Every ED should have access to medical educational materials via the Internet, computer-based training, and other effective education methods for point-of-service information, continuing medical education, and training. 2) Real-time automated tools should be integrated into Emergency Department Information Systems [EDIS] for contemporaneous education. Virtual reality [VR]: 1) Emergency physicians and emergency medicine societies should become more involved in VR development and assessment. 2) Nationally accepted protocols for the proper assessment of VR applications should be adopted and large multi-center groups should be formed to perform these studies. High-fidelity simulation: Emergency medicine residency programs should consider the use of high-fidelity patient simulators to enhance the teaching and evaluation of core competencies among trainees. Across specialties, patient simulation, virtual reality, and the Web will soon enable medical students and residents to... see one, simulate many, do one competently, and teach everyone.

High-speed and high-fidelity system and method for collecting network traffic

DOEpatents

Weigle, Eric H [Los Alamos, NM

2010-08-24

A system is provided for the high-speed and high-fidelity collection of network traffic. The system can collect traffic at gigabit-per-second (Gbps) speeds, scale to terabit-per-second (Tbps) speeds, and support additional functions such as real-time network intrusion detection. The present system uses a dedicated operating system for traffic collection to maximize efficiency, scalability, and performance. A scalable infrastructure and apparatus for the present system is provided by splitting the work performed on one host onto multiple hosts. The present system simultaneously addresses the issues of scalability, performance, cost, and adaptability with respect to network monitoring, collection, and other network tasks. In addition to high-speed and high-fidelity network collection, the present system provides a flexible infrastructure to perform virtually any function at high speeds such as real-time network intrusion detection and wide-area network emulation for research purposes.

Effects of simulation fidelity on user experience in virtual fear of public speaking training - an experimental study.

PubMed

Poeschl, Sandra; Doering, Nicola

2014-01-01

Realistic models in virtual reality training applications are considered to positively influence presence and performance. The experimental study presented, analyzed the effect of simulation fidelity (static vs. animated audience) on presence as a prerequisite for performance in a prototype virtual fear of public speaking application with a sample of N = 40 academic non-phobic users. Contrary to the state of research, no influence was shown on virtual presence and perceived realism, but an animated audience led to significantly higher effects in anxiety during giving a talk. Although these findings could be explained by an application that might not have been realistic enough, they still question the role of presence as a mediating factor in virtual exposure applications.

Modeling for Fidelity: virtual mentorship by scientists fosters teacher self-efficacy and promotes implementation of novel high school biomedical curricula.

PubMed

Malanson, Katherine; Jacque, Berri; Faux, Russell; Meiri, Karina F

2014-01-01

This small-scale comparison case study evaluates the impact of an innovative approach to teacher professional development designed to promote implementation of a novel cutting edge high school neurological disorders curriculum. 'Modeling for Fidelity' (MFF) centers on an extended mentor relationship between teachers and biomedical scientists carried out in a virtual format in conjunction with extensive online educative materials. Four teachers from different diverse high schools in Massachusetts and Ohio who experienced MFF contextualized to a 6-week Neurological Disorders curriculum with the same science mentor were compared to a teacher who had experienced an intensive in-person professional development contextualized to the same curriculum with the same mentor. Fidelity of implementation was measured directly using an established metric and indirectly via student performance. The results show that teachers valued MFF, particularly the mentor relationship and were able to use it effectively to ensure critical components of the learning objectives were preserved. Moreover their students performed equivalently to those whose teacher had experienced intensive in-person professional development. Participants in all school settings demonstrated large (Cohen's d>2.0) and significant (p<0.0001 per-post) changes in conceptual knowledge as well as self-efficacy towards learning about neurological disorders (Cohen's d>1.5, p<0.0001 pre-post). The data demonstrates that the virtual mentorship format in conjunction with extensive online educative materials is an effective method of developing extended interactions between biomedical scientists and teachers that are scalable and not geographically constrained, facilitating teacher implementation of novel cutting-edge curricula.

The effects of substitute multisensory feedback on task performance and the sense of presence in a virtual reality environment

PubMed Central

Milella, Ferdinando; Pinto, Carlo; Cant, Iain; White, Mark; Meyer, Georg

2018-01-01

Objective and subjective measures of performance in virtual reality environments increase as more sensory cues are delivered and as simulation fidelity increases. Some cues (colour or sound) are easier to present than others (object weight, vestibular cues) so that substitute cues can be used to enhance informational content in a simulation at the expense of simulation fidelity. This study evaluates how substituting cues in one modality by alternative cues in another modality affects subjective and objective performance measures in a highly immersive virtual reality environment. Participants performed a wheel change in a virtual reality (VR) environment. Auditory, haptic and visual cues, signalling critical events in the simulation, were manipulated in a factorial design. Subjective ratings were recorded via questionnaires. The time taken to complete the task was used as an objective performance measure. The results show that participants performed best and felt an increased sense of immersion and involvement, collectively referred to as ‘presence’, when substitute multimodal sensory feedback was provided. Significant main effects of audio and tactile cues on task performance and on participants' subjective ratings were found. A significant negative relationship was found between the objective (overall completion times) and subjective (ratings of presence) performance measures. We conclude that increasing informational content, even if it disrupts fidelity, enhances performance and user’s overall experience. On this basis we advocate the use of substitute cues in VR environments as an efficient method to enhance performance and user experience. PMID:29390023

The effects of substitute multisensory feedback on task performance and the sense of presence in a virtual reality environment.

PubMed

Cooper, Natalia; Milella, Ferdinando; Pinto, Carlo; Cant, Iain; White, Mark; Meyer, Georg

2018-01-01

Objective and subjective measures of performance in virtual reality environments increase as more sensory cues are delivered and as simulation fidelity increases. Some cues (colour or sound) are easier to present than others (object weight, vestibular cues) so that substitute cues can be used to enhance informational content in a simulation at the expense of simulation fidelity. This study evaluates how substituting cues in one modality by alternative cues in another modality affects subjective and objective performance measures in a highly immersive virtual reality environment. Participants performed a wheel change in a virtual reality (VR) environment. Auditory, haptic and visual cues, signalling critical events in the simulation, were manipulated in a factorial design. Subjective ratings were recorded via questionnaires. The time taken to complete the task was used as an objective performance measure. The results show that participants performed best and felt an increased sense of immersion and involvement, collectively referred to as 'presence', when substitute multimodal sensory feedback was provided. Significant main effects of audio and tactile cues on task performance and on participants' subjective ratings were found. A significant negative relationship was found between the objective (overall completion times) and subjective (ratings of presence) performance measures. We conclude that increasing informational content, even if it disrupts fidelity, enhances performance and user's overall experience. On this basis we advocate the use of substitute cues in VR environments as an efficient method to enhance performance and user experience.

Virtual reality in surgical skills training.

PubMed

Palter, Vanessa N; Grantcharov, Teodor P

2010-06-01

With recent concerns regarding patient safety, and legislation regarding resident work hours, it is accepted that a certain amount of surgical skills training will transition to the surgical skills laboratory. Virtual reality offers enormous potential to enhance technical and non-technical skills training outside the operating room. Virtual-reality systems range from basic low-fidelity devices to highly complex virtual environments. These systems can act as training and assessment tools, with the learned skills effectively transferring to an analogous clinical situation. Recent developments include expanding the role of virtual reality to allow for holistic, multidisciplinary team training in simulated operating rooms, and focusing on the role of virtual reality in evidence-based surgical curriculum design. Copyright 2010 Elsevier Inc. All rights reserved.

Perceptual Fidelity vs. Engineering Compromises In Virtual Acoustic Displays

NASA Technical Reports Server (NTRS)

Wenzel, Elizabeth M.; Ahumada, Albert (Technical Monitor)

1997-01-01

Immersive, three-dimensional displays are increasingly becoming a goal of advanced human-machine interfaces. While the technology for achieving truly useful multisensory environments is still being developed, techniques for generating three-dimensional sound are now both sophisticated and practical enough to be applied to acoustic displays. The ultimate goal of virtual acoustics is to simulate the complex acoustic field experienced by a listener freely moving around within an environment. Of course, such complexity, freedom of movement and interactively is not always possible in a "true" virtual environment, much less in lower-fidelity multimedia systems. However, many of the perceptual and engineering constraints (and frustrations) that researchers, engineers and listeners have experienced in virtual audio are relevant to multimedia. In fact, some of the problems that have been studied will be even more of an issue for lower fidelity systems that are attempting to address the requirements of a huge, diverse and ultimately unknown audience. Examples include individual differences in head-related transfer functions, a lack of real interactively (head-tracking) in many multimedia displays, and perceptual degradation due to low sampling rates and/or low-bit compression. This paper discusses some of the engineering Constraints faced during implementation of virtual acoustic environments and the perceptual consequences of these constraints. Specific examples are given for NASA applications such as telerobotic control, aeronautical displays, and shuttle launch communications. An attempt will also be made to relate these issues to low-fidelity implementations such as the internet.

Perceptual Fidelity Versus Engineering Compromises in Virtual Acoustic Displays

NASA Technical Reports Server (NTRS)

Wenzel, Elizabeth M.; Ellis, Stephen R. (Technical Monitor); Frey, Mary Anne (Technical Monitor); Schneider, Victor S. (Technical Monitor)

1997-01-01

Immersive, three-dimensional displays are increasingly becoming a goal of advanced human-machine interfaces. While the technology for achieving truly useful multisensory environments is still being developed, techniques for generating three-dimensional sound are now both sophisticated and practical enough to be applied to acoustic displays. The ultimate goal of virtual acoustics is to simulate the complex acoustic field experienced by a listener freely moving around within an environment. Of course, such complexity, freedom of movement and interactivity is not always possible in a 'true' virtual environment, much less in lower-fidelity multimedia systems. However, many of the perceptual and engineering constraints (and frustrations) that researchers, engineers and listeners have experienced in virtual audio are relevant to multimedia. In fact, some of the problems that have been studied will be even more of an issue for lower fidelity systems that are attempting to address the requirements of a huge, diverse and ultimately unknown audience. Examples include individual differences in head-related transfer functions, A lack of real interactively (head-tracking) in many multimedia displays, and perceptual degradation due to low sampling rates and/or low-bit compression. This paper discusses some of the engineering constraints faced during implementation of virtual acoustic environments and the perceptual consequences of these constraints. Specific examples are given for NASA applications such as telerobotic control, aeronautical displays, and shuttle launch communications. An attempt will also be made to relate these issues to low-fidelity implementations such as the internet.

Modulation of Visually Evoked Postural Responses by Contextual Visual, Haptic and Auditory Information: A ‘Virtual Reality Check’

PubMed Central

Meyer, Georg F.; Shao, Fei; White, Mark D.; Hopkins, Carl; Robotham, Antony J.

2013-01-01

Externally generated visual motion signals can cause the illusion of self-motion in space (vection) and corresponding visually evoked postural responses (VEPR). These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR) environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1) visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2) real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3) visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR. PMID:23840760

Entertainment Technology and Military Virtual Environments

DTIC Science & Technology

2001-03-01

over long television with the World Wide Web, and the continued distances. Defining (modeling), organizing and rapid growth of multiplayer Internet 3D...for "high fidelity": hurt in factional violence while preventing, as much as verisimilitude, possible, new flare ups among the factions. By sharing

Vibrons in finite size molecular lattices: a route for high-fidelity quantum state transfer at room temperature.

PubMed

Pouthier, Vincent

2012-11-07

A communication protocol is proposed in which vibron-mediated quantum state transfer takes place in a molecular lattice. We consider two distant molecular groups grafted on each side of the lattice. These groups form two quantum computers where vibrational qubits are implemented and received. The lattice defines the communication channel along which a vibron delocalizes and interacts with a phonon bath. Using quasi-degenerate perturbation theory, vibron-phonon entanglement is taken into account through the effective Hamiltonian concept. A vibron is thus dressed by a virtual phonon cloud whereas a phonon is clothed by virtual vibronic transitions. It is shown that three quasi-degenerate dressed states define the relevant paths followed by a vibron to tunnel between the computers. When the coupling between the computers and the lattice is judiciously chosen, constructive interference takes place between these paths. Phonon-induced decoherence is minimized and a high-fidelity quantum state transfer occurs over a broad temperature range.

Evaluating Multiple Levels of an Interaction Fidelity Continuum on Performance and Learning in Near-Field Training Simulations.

PubMed

Bhargava, Ayush; Bertrand, Jeffrey W; Gramopadhye, Anand K; Madathil, Kapil C; Babu, Sabarish V

2018-04-01

With costs of head-mounted displays (HMDs) and tracking technology decreasing rapidly, various virtual reality applications are being widely adopted for education and training. Hardware advancements have enabled replication of real-world interactions in virtual environments to a large extent, paving the way for commercial grade applications that provide a safe and risk-free training environment at a fraction of the cost. But this also mandates the need to develop more intrinsic interaction techniques and to empirically evaluate them in a more comprehensive manner. Although there exists a body of previous research that examines the benefits of selected levels of interaction fidelity on performance, few studies have investigated the constituent components of fidelity in a Interaction Fidelity Continuum (IFC) with several system instances and their respective effects on performance and learning in the context of a real-world skills training application. Our work describes a large between-subjects investigation conducted over several years that utilizes bimanual interaction metaphors at six discrete levels of interaction fidelity to teach basic precision metrology concepts in a near-field spatial interaction task in VR. A combined analysis performed on the data compares and contrasts the six different conditions and their overall effects on performance and learning outcomes, eliciting patterns in the results between the discrete application points on the IFC. With respect to some performance variables, results indicate that simpler restrictive interaction metaphors and highest fidelity metaphors perform better than medium fidelity interaction metaphors. In light of these results, a set of general guidelines are created for developers of spatial interaction metaphors in immersive virtual environments for precise fine-motor skills training simulations.

The effect of contextual sound cues on visual fidelity perception.

PubMed

Rojas, David; Cowan, Brent; Kapralos, Bill; Collins, Karen; Dubrowski, Adam

2014-01-01

Previous work has shown that sound can affect the perception of visual fidelity. Here we build upon this previous work by examining the effect of contextual sound cues (i.e., sounds that are related to the visuals) on visual fidelity perception. Results suggest that contextual sound cues do influence visual fidelity perception and, more specifically, our perception of visual fidelity increases with contextual sound cues. These results have implications for designers of multimodal virtual worlds and serious games that, with the appropriate use of contextual sounds, can reduce visual rendering requirements without a corresponding decrease in the perception of visual fidelity.

The Computing And Interdisciplinary Systems Office: Annual Review and Planning Meeting

NASA Technical Reports Server (NTRS)

Lytle, John K.

2003-01-01

The goal of this research is to develop an advanced engineering analysis system that enables high-fidelity, multi-disciplinary, full propulsion system simulations to be performed early in the design process (a virtual test cell that integrates propulsion and information technologies). This will enable rapid, high-confidence, cost-effective design of revolutionary systems.

Structural flexibility of laparoscopic instruments: implication for the design of virtual reality simulators.

PubMed

Shang, D; Carnahan, H; Dubrowski, A

2006-01-01

Laparoscopic training, under simulated settings, benefits from high fidelity models of the actual environment. This study was aimed at reducing uncertainty in the displacement and loads experienced by a laparoscopic instrument during surgical training. Infrared tracking of laparoscopic instruments is ineffective when real tissues attenuate the infrared signals. Incorporating the use of strain gauges for tip deflection measurements allows for online motion and load tracking during a procedure. Strain gauge voltages and infrared markers indicating displacement were both linear with respect to loads up to 700 grams. The resultant strain gauge voltage was equated to deflection values with a calibration constant. The results serve two purposes. First, it may enable the tracking and analysis of the skill level of novice surgeons using bench models. Second, the mechanical model of each instrument can be quantified and incorporated into virtual simulations, thus increasing model fidelity, effectively leading to better learning.

Runtime Performance and Virtual Network Control Alternatives in VM-Based High-Fidelity Network Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoginath, Srikanth B; Perumalla, Kalyan S; Henz, Brian J

2012-01-01

In prior work (Yoginath and Perumalla, 2011; Yoginath, Perumalla and Henz, 2012), the motivation, challenges and issues were articulated in favor of virtual time ordering of Virtual Machines (VMs) in network simulations hosted on multi-core machines. Two major components in the overall virtualization challenge are (1) virtual timeline establishment and scheduling of VMs, and (2) virtualization of inter-VM communication. Here, we extend prior work by presenting scaling results for the first component, with experiment results on up to 128 VMs scheduled in virtual time order on a single 12-core host. We also explore the solution space of design alternatives formore » the second component, and present performance results from a multi-threaded, multi-queue implementation of inter-VM network control for synchronized execution with VM scheduling, incorporated in our NetWarp simulation system.« less

Computational Virtual Reality (VR) as a human-computer interface in the operation of telerobotic systems

NASA Technical Reports Server (NTRS)

Bejczy, Antal K.

1995-01-01

This presentation focuses on the application of computer graphics or 'virtual reality' (VR) techniques as a human-computer interface tool in the operation of telerobotic systems. VR techniques offer very valuable task realization aids for planning, previewing and predicting robotic actions, operator training, and for visual perception of non-visible events like contact forces in robotic tasks. The utility of computer graphics in telerobotic operation can be significantly enhanced by high-fidelity calibration of virtual reality images to actual TV camera images. This calibration will even permit the creation of artificial (synthetic) views of task scenes for which no TV camera views are available.

Effects of Field of View and Visual Complexity on Virtual Reality Training Effectiveness for a Visual Scanning Task

DOE PAGES

Ragan, Eric D.; Bowman, Doug A.; Kopper, Regis; ...

2015-02-13

Virtual reality training systems are commonly used in a variety of domains, and it is important to understand how the realism of a training simulation influences training effectiveness. The paper presents a framework for evaluating the effects of virtual reality fidelity based on an analysis of a simulation’s display, interaction, and scenario components. Following this framework, we conducted a controlled experiment to test the effects of fidelity on training effectiveness for a visual scanning task. The experiment varied the levels of field of view and visual realism during a training phase and then evaluated scanning performance with the simulator’s highestmore » level of fidelity. To assess scanning performance, we measured target detection and adherence to a prescribed strategy. The results show that both field of view and visual realism significantly affected target detection during training; higher field of view led to better performance and higher visual realism worsened performance. Additionally, the level of visual realism during training significantly affected learning of the prescribed visual scanning strategy, providing evidence that high visual realism was important for learning the technique. The results also demonstrate that task performance during training was not always a sufficient measure of mastery of an instructed technique. That is, if learning a prescribed strategy or skill is the goal of a training exercise, performance in a simulation may not be an appropriate indicator of effectiveness outside of training—evaluation in a more realistic setting may be necessary.« less

Virtual Worlds for Virtual Organizing

NASA Astrophysics Data System (ADS)

Rhoten, Diana; Lutters, Wayne

The members and resources of a virtual organization are dispersed across time and space, yet they function as a coherent entity through the use of technologies, networks, and alliances. As virtual organizations proliferate and become increasingly important in society, many may exploit the technical architecture s of virtual worlds, which are the confluence of computer-mediated communication, telepresence, and virtual reality originally created for gaming. A brief socio-technical history describes their early origins and the waves of progress followed by stasis that brought us to the current period of renewed enthusiasm. Examination of contemporary examples demonstrates how three genres of virtual worlds have enabled new arenas for virtual organizing: developer-defined closed worlds, user-modifiable quasi-open worlds, and user-generated open worlds. Among expected future trends are an increase in collaboration born virtually rather than imported from existing organizations, a tension between high-fidelity recreations of the physical world and hyper-stylized imaginations of fantasy worlds, and the growth of specialized worlds optimized for particular sectors, companies, or cultures.

A New Design for Airway Management Training with Mixed Reality and High Fidelity Modeling.

PubMed

Shen, Yunhe; Hananel, David; Zhao, Zichen; Burke, Daniel; Ballas, Crist; Norfleet, Jack; Reihsen, Troy; Sweet, Robert

2016-01-01

Restoring airway function is a vital task in many medical scenarios. Although various simulation tools have been available for learning such skills, recent research indicated that fidelity in simulating airway management deserves further improvements. In this study, we designed and implemented a new prototype for practicing relevant tasks including laryngoscopy, intubation and cricothyrotomy. A large amount of anatomical details or landmarks were meticulously selected and reconstructed from medical scans, and 3D-printed or molded to the airway intervention model. This training model was augmented by virtually and physically presented interactive modules, which are interoperable with motion tracking and sensor data feedback. Implementation results showed that this design is a feasible approach to develop higher fidelity airway models that can be integrated with mixed reality interfaces.

Virtual microphone sensing through vibro-acoustic modelling and Kalman filtering

NASA Astrophysics Data System (ADS)

van de Walle, A.; Naets, F.; Desmet, W.

2018-05-01

This work proposes a virtual microphone methodology which enables full field acoustic measurements for vibro-acoustic systems. The methodology employs a Kalman filtering framework in order to combine a reduced high-fidelity vibro-acoustic model with a structural excitation measurement and small set of real microphone measurements on the system under investigation. By employing model order reduction techniques, a high order finite element model can be converted in a much smaller model which preserves the desired accuracy and maintains the main physical properties of the original model. Due to the low order of the reduced-order model, it can be effectively employed in a Kalman filter. The proposed methodology is validated experimentally on a strongly coupled vibro-acoustic system. The virtual sensor vastly improves the accuracy with respect to regular forward simulation. The virtual sensor also allows to recreate the full sound field of the system, which is very difficult/impossible to do through classical measurements.

Virtual environments for scene of crime reconstruction and analysis

NASA Astrophysics Data System (ADS)

Howard, Toby L. J.; Murta, Alan D.; Gibson, Simon

2000-02-01

This paper describes research conducted in collaboration with Greater Manchester Police (UK), to evalute the utility of Virtual Environments for scene of crime analysis, forensic investigation, and law enforcement briefing and training. We present an illustrated case study of the construction of a high-fidelity virtual environment, intended to match a particular real-life crime scene as closely as possible. We describe and evaluate the combination of several approaches including: the use of the Manchester Scene Description Language for constructing complex geometrical models; the application of a radiosity rendering algorithm with several novel features based on human perceptual consideration; texture extraction from forensic photography; and experiments with interactive walkthroughs and large-screen stereoscopic display of the virtual environment implemented using the MAVERIK system. We also discuss the potential applications of Virtual Environment techniques in the Law Enforcement and Forensic communities.

Point-of-care ultrasound education: the increasing role of simulation and multimedia resources.

PubMed

Lewiss, Resa E; Hoffmann, Beatrice; Beaulieu, Yanick; Phelan, Mary Beth

2014-01-01

This article reviews the current technology, literature, teaching models, and methods associated with simulation-based point-of-care ultrasound training. Patient simulation appears particularly well suited for learning point-of-care ultrasound, which is a required core competency for emergency medicine and other specialties. Work hour limitations have reduced the opportunities for clinical practice, and simulation enables practicing a skill multiple times before it may be used on patients. Ultrasound simulators can be categorized into 2 groups: low and high fidelity. Low-fidelity simulators are usually static simulators, meaning that they have nonchanging anatomic examples for sonographic practice. Advantages are that the model may be reused over time, and some simulators can be homemade. High-fidelity simulators are usually high-tech and frequently consist of many computer-generated cases of virtual sonographic anatomy that can be scanned with a mock probe. This type of equipment is produced commercially and is more expensive. High-fidelity simulators provide students with an active and safe learning environment and make a reproducible standardized assessment of many different ultrasound cases possible. The advantages and disadvantages of using low- versus high-fidelity simulators are reviewed. An additional concept used in simulation-based ultrasound training is blended learning. Blended learning may include face-to-face or online learning often in combination with a learning management system. Increasingly, with simulation and Web-based learning technologies, tools are now available to medical educators for the standardization of both ultrasound skills training and competency assessment.

Virtual Transgenics: Using a Molecular Biology Simulation to Impact Student Academic Achievement and Attitudes

ERIC Educational Resources Information Center

Shegog, Ross; Lazarus, Melanie M.; Murray, Nancy G.; Diamond, Pamela M.; Sessions, Nathalie; Zsigmond, Eva

2012-01-01

The transgenic mouse model is useful for studying the causes and potential cures for human genetic diseases. Exposing high school biology students to laboratory experience in developing transgenic animal models is logistically prohibitive. Computer-based simulation, however, offers this potential in addition to advantages of fidelity and reach.…

UAV, LiDAR & ground-based surveying from Stackpole Quay: best practice for accuracy of virtual outcrops and structural models

NASA Astrophysics Data System (ADS)

Cawood, A.; Bond, C. E.; Howell, J.; Totake, Y.

2016-12-01

Virtual outcrops derived from techniques such as LiDAR and SfM (digital photogrammetry) provide a viable and potentially powerful addition or alternative to traditional field studies, given the large amounts of raw data that can be acquired rapidly and safely. The use of these digital representations of outcrops as a source of geological data has increased greatly in the past decade, and as such, the accuracy and precision of these new acquisition methods applied to geological problems has been addressed by a number of authors. Little work has been done, however, on the integration of virtual outcrops into fundamental structural geology workflows and to systematically studying the fidelity of the data derived from them. Here, we use the classic Stackpole Quay syncline outcrop in South Wales to quantitatively evaluate the accuracy of three virtual outcrop models (LiDAR, aerial and terrestrial digital photogrammetry) compared to data collected directly in the field. Using these structural data, we have built 2D and 3D geological models which make predictions of fold geometries. We examine the fidelity of virtual outcrops generated using different acquisition techniques to outcrop geology and how these affect model building and final outcomes. Finally, we utilize newly acquired data to deterministically test model validity. Based upon these results, we find that acquisition of digital imagery by UAS (Unmanned Autonomous Vehicle) yields highly accurate virtual outcrops when compared to terrestrial methods, allowing the construction of robust data-driven predictive models. Careful planning, survey design and choice of suitable acquisition method are, however, of key importance for best results.

Floating Node Method and Virtual Crack Closure Technique for Modeling Matrix Cracking-Delamination Interaction

NASA Technical Reports Server (NTRS)

DeCarvalho, N. V.; Chen, B. Y.; Pinho, S. T.; Baiz, P. M.; Ratcliffe, J. G.; Tay, T. E.

2013-01-01

A novel approach is proposed for high-fidelity modeling of progressive damage and failure in composite materials that combines the Floating Node Method (FNM) and the Virtual Crack Closure Technique (VCCT) to represent multiple interacting failure mechanisms in a mesh-independent fashion. In this study, the approach is applied to the modeling of delamination migration in cross-ply tape laminates. Delamination, matrix cracking, and migration are all modeled using fracture mechanics based failure and migration criteria. The methodology proposed shows very good qualitative and quantitative agreement with experiments.

Floating Node Method and Virtual Crack Closure Technique for Modeling Matrix Cracking-Delamination Migration

NASA Technical Reports Server (NTRS)

DeCarvalho, Nelson V.; Chen, B. Y.; Pinho, Silvestre T.; Baiz, P. M.; Ratcliffe, James G.; Tay, T. E.

2013-01-01

A novel approach is proposed for high-fidelity modeling of progressive damage and failure in composite materials that combines the Floating Node Method (FNM) and the Virtual Crack Closure Technique (VCCT) to represent multiple interacting failure mechanisms in a mesh-independent fashion. In this study, the approach is applied to the modeling of delamination migration in cross-ply tape laminates. Delamination, matrix cracking, and migration are all modeled using fracture mechanics based failure and migration criteria. The methodology proposed shows very good qualitative and quantitative agreement with experiments.

Creating virtual humans for simulation-based training and planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stansfield, S.; Sobel, A.

1998-05-12

Sandia National Laboratories has developed a distributed, high fidelity simulation system for training and planning small team Operations. The system provides an immersive environment populated by virtual objects and humans capable of displaying complex behaviors. The work has focused on developing the behaviors required to carry out complex tasks and decision making under stress. Central to this work are techniques for creating behaviors for virtual humans and for dynamically assigning behaviors to CGF to allow scenarios without fixed outcomes. Two prototype systems have been developed that illustrate these capabilities: MediSim, a trainer for battlefield medics and VRaptor, a system formore » planning, rehearsing and training assault operations.« less

Full State Feedback Control for Virtual Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Jay Tillay

This report presents an object-oriented implementation of full state feedback control for virtual power plants (VPP). The components of the VPP full state feedback control are (1) objectoriented high-fidelity modeling for all devices in the VPP; (2) Distribution System Distributed Quasi-Dynamic State Estimation (DS-DQSE) that enables full observability of the VPP by augmenting actual measurements with virtual, derived and pseudo measurements and performing the Quasi-Dynamic State Estimation (QSE) in a distributed manner, and (3) automated formulation of the Optimal Power Flow (OPF) in real time using the output of the DS-DQSE, and solving the distributed OPF to provide the optimalmore » control commands to the DERs of the VPP.« less

Medical Robotic and Telesurgical Simulation and Education Research

DTIC Science & Technology

2014-09-01

versions of the device for sale . A B 13 C D Figure 6: The Computer Aided Design of the Dome (A-B) and the last High Fidelity Prototype (C...FRxS Advanced Etc. Etc. Virtual Worlds for Robotic Surgery 31 HumanSim Preview for iPad is available on iTunes VIRTURLHEROES OMS ION O F

NASA Virtual Glovebox: An Immersive Virtual Desktop Environment for Training Astronauts in Life Science Experiments

NASA Technical Reports Server (NTRS)

Twombly, I. Alexander; Smith, Jeffrey; Bruyns, Cynthia; Montgomery, Kevin; Boyle, Richard

2003-01-01

The International Space Station will soon provide an unparalleled research facility for studying the near- and longer-term effects of microgravity on living systems. Using the Space Station Glovebox Facility - a compact, fully contained reach-in environment - astronauts will conduct technically challenging life sciences experiments. Virtual environment technologies are being developed at NASA Ames Research Center to help realize the scientific potential of this unique resource by facilitating the experimental hardware and protocol designs and by assisting the astronauts in training. The Virtual GloveboX (VGX) integrates high-fidelity graphics, force-feedback devices and real- time computer simulation engines to achieve an immersive training environment. Here, we describe the prototype VGX system, the distributed processing architecture used in the simulation environment, and modifications to the visualization pipeline required to accommodate the display configuration.

Development of a low-cost virtual reality workstation for training and education

NASA Technical Reports Server (NTRS)

Phillips, James A.

1996-01-01

Virtual Reality (VR) is a set of breakthrough technologies that allow a human being to enter and fully experience a 3-dimensional, computer simulated environment. A true virtual reality experience meets three criteria: (1) it involves 3-dimensional computer graphics; (2) it includes real-time feedback and response to user actions; and (3) it must provide a sense of immersion. Good examples of a virtual reality simulator are the flight simulators used by all branches of the military to train pilots for combat in high performance jet fighters. The fidelity of such simulators is extremely high -- but so is the price tag, typically millions of dollars. Virtual reality teaching and training methods are manifestly effective, but the high cost of VR technology has limited its practical application to fields with big budgets, such as military combat simulation, commercial pilot training, and certain projects within the space program. However, in the last year there has been a revolution in the cost of VR technology. The speed of inexpensive personal computers has increased dramatically, especially with the introduction of the Pentium processor and the PCI bus for IBM-compatibles, and the cost of high-quality virtual reality peripherals has plummeted. The result is that many public schools, colleges, and universities can afford a PC-based workstation capable of running immersive virtual reality applications. My goal this summer was to assemble and evaluate such a system.

Using immersive simulation for training first responders for mass casualty incidents.

PubMed

Wilkerson, William; Avstreih, Dan; Gruppen, Larry; Beier, Klaus-Peter; Woolliscroft, James

2008-11-01

A descriptive study was performed to better understand the possible utility of immersive virtual reality simulation for training first responders in a mass casualty event. Utilizing a virtual reality cave automatic virtual environment (CAVE) and high-fidelity human patient simulator (HPS), a group of experts modeled a football stadium that experienced a terrorist explosion during a football game. Avatars (virtual patients) were developed by expert consensus that demonstrated a spectrum of injuries ranging from death to minor lacerations. A group of paramedics was assessed by observation for decisions made and action taken. A critical action checklist was created and used for direct observation and viewing videotaped recordings. Of the 12 participants, only 35.7% identified the type of incident they encountered. None identified a secondary device that was easily visible. All participants were enthusiastic about the simulation and provided valuable comments and insights. Learner feedback and expert performance review suggests that immersive training in a virtual environment has the potential to be a powerful tool to train first responders for high-acuity, low-frequency events, such as a terrorist attack.

Physical environment virtualization for human activities recognition

NASA Astrophysics Data System (ADS)

Poshtkar, Azin; Elangovan, Vinayak; Shirkhodaie, Amir; Chan, Alex; Hu, Shuowen

2015-05-01

Human activity recognition research relies heavily on extensive datasets to verify and validate performance of activity recognition algorithms. However, obtaining real datasets are expensive and highly time consuming. A physics-based virtual simulation can accelerate the development of context based human activity recognition algorithms and techniques by generating relevant training and testing videos simulating diverse operational scenarios. In this paper, we discuss in detail the requisite capabilities of a virtual environment to aid as a test bed for evaluating and enhancing activity recognition algorithms. To demonstrate the numerous advantages of virtual environment development, a newly developed virtual environment simulation modeling (VESM) environment is presented here to generate calibrated multisource imagery datasets suitable for development and testing of recognition algorithms for context-based human activities. The VESM environment serves as a versatile test bed to generate a vast amount of realistic data for training and testing of sensor processing algorithms. To demonstrate the effectiveness of VESM environment, we present various simulated scenarios and processed results to infer proper semantic annotations from the high fidelity imagery data for human-vehicle activity recognition under different operational contexts.

Communication Architecture in Mixed-Reality Simulations of Unmanned Systems

PubMed Central

2018-01-01

Verification of the correct functionality of multi-vehicle systems in high-fidelity scenarios is required before any deployment of such a complex system, e.g., in missions of remote sensing or in mobile sensor networks. Mixed-reality simulations where both virtual and physical entities can coexist and interact have been shown to be beneficial for development, testing, and verification of such systems. This paper deals with the problems of designing a certain communication subsystem for such highly desirable realistic simulations. Requirements of this communication subsystem, including proper addressing, transparent routing, visibility modeling, or message management, are specified prior to designing an appropriate solution. Then, a suitable architecture of this communication subsystem is proposed together with solutions to the challenges that arise when simultaneous virtual and physical message transmissions occur. The proposed architecture can be utilized as a high-fidelity network simulator for vehicular systems with implicit mobility models that are given by real trajectories of the vehicles. The architecture has been utilized within multiple projects dealing with the development and practical deployment of multi-UAV systems, which support the architecture’s viability and advantages. The provided experimental results show the achieved similarity of the communication characteristics of the fully deployed hardware setup to the setup utilizing the proposed mixed-reality architecture. PMID:29538290

Communication Architecture in Mixed-Reality Simulations of Unmanned Systems.

PubMed

Selecký, Martin; Faigl, Jan; Rollo, Milan

2018-03-14

Verification of the correct functionality of multi-vehicle systems in high-fidelity scenarios is required before any deployment of such a complex system, e.g., in missions of remote sensing or in mobile sensor networks. Mixed-reality simulations where both virtual and physical entities can coexist and interact have been shown to be beneficial for development, testing, and verification of such systems. This paper deals with the problems of designing a certain communication subsystem for such highly desirable realistic simulations. Requirements of this communication subsystem, including proper addressing, transparent routing, visibility modeling, or message management, are specified prior to designing an appropriate solution. Then, a suitable architecture of this communication subsystem is proposed together with solutions to the challenges that arise when simultaneous virtual and physical message transmissions occur. The proposed architecture can be utilized as a high-fidelity network simulator for vehicular systems with implicit mobility models that are given by real trajectories of the vehicles. The architecture has been utilized within multiple projects dealing with the development and practical deployment of multi-UAV systems, which support the architecture's viability and advantages. The provided experimental results show the achieved similarity of the communication characteristics of the fully deployed hardware setup to the setup utilizing the proposed mixed-reality architecture.

Modeling for Fidelity: Virtual Mentorship by Scientists Fosters Teacher Self-Efficacy and Promotes Implementation of Novel High School Biomedical Curricula

PubMed Central

Malanson, Katherine; Jacque, Berri; Faux, Russell; Meiri, Karina F.

2014-01-01

This small-scale comparison case study evaluates the impact of an innovative approach to teacher professional development designed to promote implementation of a novel cutting edge high school neurological disorders curriculum. ‘Modeling for Fidelity’ (MFF) centers on an extended mentor relationship between teachers and biomedical scientists carried out in a virtual format in conjunction with extensive online educative materials. Four teachers from different diverse high schools in Massachusetts and Ohio who experienced MFF contextualized to a 6-week Neurological Disorders curriculum with the same science mentor were compared to a teacher who had experienced an intensive in-person professional development contextualized to the same curriculum with the same mentor. Fidelity of implementation was measured directly using an established metric and indirectly via student performance. The results show that teachers valued MFF, particularly the mentor relationship and were able to use it effectively to ensure critical components of the learning objectives were preserved. Moreover their students performed equivalently to those whose teacher had experienced intensive in-person professional development. Participants in all school settings demonstrated large (Cohen's d>2.0) and significant (p<0.0001 per-post) changes in conceptual knowledge as well as self-efficacy towards learning about neurological disorders (Cohen's d>1.5, p<0.0001 pre-post). The data demonstrates that the virtual mentorship format in conjunction with extensive online educative materials is an effective method of developing extended interactions between biomedical scientists and teachers that are scalable and not geographically constrained, facilitating teacher implementation of novel cutting-edge curricula. PMID:25551645

Assessing Upper Extremity Motor Function in Practice of Virtual Activities of Daily Living

PubMed Central

Adams, Richard J.; Lichter, Matthew D.; Krepkovich, Eileen T.; Ellington, Allison; White, Marga; Diamond, Paul T.

2015-01-01

A study was conducted to investigate the criterion validity of measures of upper extremity (UE) motor function derived during practice of virtual activities of daily living (ADLs). Fourteen hemiparetic stroke patients employed a Virtual Occupational Therapy Assistant (VOTA), consisting of a high-fidelity virtual world and a Kinect™ sensor, in four sessions of approximately one hour in duration. An Unscented Kalman Filter-based human motion tracking algorithm estimated UE joint kinematics in real-time during performance of virtual ADL activities, enabling both animation of the user’s avatar and automated generation of metrics related to speed and smoothness of motion. These metrics, aggregated over discrete sub-task elements during performance of virtual ADLs, were compared to scores from an established assessment of UE motor performance, the Wolf Motor Function Test (WMFT). Spearman’s rank correlation analysis indicates a moderate correlation between VOTA-derived metrics and the time-based WMFT assessments, supporting the criterion validity of VOTA measures as a means of tracking patient progress during an UE rehabilitation program that includes practice of virtual ADLs. PMID:25265612

Assessing upper extremity motor function in practice of virtual activities of daily living.

PubMed

Adams, Richard J; Lichter, Matthew D; Krepkovich, Eileen T; Ellington, Allison; White, Marga; Diamond, Paul T

2015-03-01

A study was conducted to investigate the criterion validity of measures of upper extremity (UE) motor function derived during practice of virtual activities of daily living (ADLs). Fourteen hemiparetic stroke patients employed a Virtual Occupational Therapy Assistant (VOTA), consisting of a high-fidelity virtual world and a Kinect™ sensor, in four sessions of approximately one hour in duration. An unscented Kalman Filter-based human motion tracking algorithm estimated UE joint kinematics in real-time during performance of virtual ADL activities, enabling both animation of the user's avatar and automated generation of metrics related to speed and smoothness of motion. These metrics, aggregated over discrete sub-task elements during performance of virtual ADLs, were compared to scores from an established assessment of UE motor performance, the Wolf Motor Function Test (WMFT). Spearman's rank correlation analysis indicates a moderate correlation between VOTA-derived metrics and the time-based WMFT assessments, supporting the criterion validity of VOTA measures as a means of tracking patient progress during an UE rehabilitation program that includes practice of virtual ADLs.

Development of Virtual Airspace Simulation Technology - Real-Time (VAST-RT) Capability 2 and Experimental Plans

NASA Technical Reports Server (NTRS)

Lehmer, R.; Ingram, C.; Jovic, S.; Alderete, J.; Brown, D.; Carpenter, D.; LaForce, S.; Panda, R.; Walker, J.; Chaplin, P.;

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ragan, Eric D.; Bowman, Doug A.; Kopper, Regis

Virtual reality training systems are commonly used in a variety of domains, and it is important to understand how the realism of a training simulation influences training effectiveness. The paper presents a framework for evaluating the effects of virtual reality fidelity based on an analysis of a simulation’s display, interaction, and scenario components. Following this framework, we conducted a controlled experiment to test the effects of fidelity on training effectiveness for a visual scanning task. The experiment varied the levels of field of view and visual realism during a training phase and then evaluated scanning performance with the simulator’s highestmore » level of fidelity. To assess scanning performance, we measured target detection and adherence to a prescribed strategy. The results show that both field of view and visual realism significantly affected target detection during training; higher field of view led to better performance and higher visual realism worsened performance. Additionally, the level of visual realism during training significantly affected learning of the prescribed visual scanning strategy, providing evidence that high visual realism was important for learning the technique. The results also demonstrate that task performance during training was not always a sufficient measure of mastery of an instructed technique. That is, if learning a prescribed strategy or skill is the goal of a training exercise, performance in a simulation may not be an appropriate indicator of effectiveness outside of training—evaluation in a more realistic setting may be necessary.« less

Comparison of fresh-frozen cadaver and high-fidelity virtual reality simulator as methods of laparoscopic training.

PubMed

Sharma, Mitesh; Horgan, Alan

2012-08-01

The aim of this study was to compare fresh-frozen cadavers (FFC) with a high-fidelity virtual reality simulator (VRS) as training tools in minimal access surgery for complex and relatively simple procedures. A prospective comparative face validity study between FFC and VRS (LAP Mentor(™)) was performed. Surgeons were recruited to perform tasks on both FFC and VRS appropriately paired to their experience level. Group A (senior) performed a laparoscopic sigmoid colectomy, Group B (intermediate) performed a laparoscopic incisional hernia repair, and Group C (junior) performed basic laparoscopic tasks (BLT) (camera manipulation, hand-eye coordination, tissue dissection and hand-transferring skills). Each subject completed a 5-point Likert-type questionnaire rating the training modalities in nine domains. Data were analysed using nonparametric tests. Forty-five surgeons were recruited to participate (15 per skill group). Median scores for subjects in Group A were significantly higher for evaluation of FFC in all nine domains compared to VRS (p < 0.01). Group B scored FFC significantly better (p < 0.05) in all domains except task replication (p = 0.06). Group C scored FFC significantly better (p < 0.01) in eight domains but not on performance feedback (p = 0.09). When compared across groups, juniors accepted VRS as a training model more than did intermediate and senior groups on most domains (p < 0.01) except team work. Fresh-frozen cadaver is perceived as a significantly overall better model for laparoscopic training than the high-fidelity VRS by all training grades, irrespective of the complexity of the operative procedure performed. VRS is still useful when training junior trainees in BLT.

A study of navigation in virtual space

NASA Technical Reports Server (NTRS)

Darken, Rudy; Sibert, John L.; Shumaker, Randy

1994-01-01

In the physical world, man has developed efficient methods for navigation and orientation. These methods are dependent on the high-fidelity stimuli presented by the environment. When placed in a virtual world which cannot offer stimuli of the same quality due to computing constraints and immature technology, tasks requiring the maintenance of position and orientation knowledge become laborious. In this paper, we present a representative set of techniques based on principles of navigation derived from real world analogs including human and avian navigation behavior and cartography. A preliminary classification of virtual worlds is presented based on the size of the world, the density of objects in the world, and the level of activity taking place in the world. We also summarize an informal study we performed to determine how the tools influenced the subjects' navigation strategies and behavior. We conclude that principles extracted from real world navigation aids such as maps can be seen to apply in virtual environments.

Electromechanical quantum simulators

NASA Astrophysics Data System (ADS)

Tacchino, F.; Chiesa, A.; LaHaye, M. D.; Carretta, S.; Gerace, D.

2018-06-01

Digital quantum simulators are among the most appealing applications of a quantum computer. Here we propose a universal, scalable, and integrated quantum computing platform based on tunable nonlinear electromechanical nano-oscillators. It is shown that very high operational fidelities for single- and two-qubits gates can be achieved in a minimal architecture, where qubits are encoded in the anharmonic vibrational modes of mechanical nanoresonators, whose effective coupling is mediated by virtual fluctuations of an intermediate superconducting artificial atom. An effective scheme to induce large single-phonon nonlinearities in nanoelectromechanical devices is explicitly discussed, thus opening the route to experimental investigation in this direction. Finally, we explicitly show the very high fidelities that can be reached for the digital quantum simulation of model Hamiltonians, by using realistic experimental parameters in state-of-the-art devices, and considering the transverse field Ising model as a paradigmatic example.

Workshop Report on Virtual Worlds and Immersive Environments

NASA Technical Reports Server (NTRS)

Langhoff, Stephanie R.; Cowan-Sharp, Jessy; Dodson, Karen E.; Damer, Bruce; Ketner, Bob

2009-01-01

The workshop revolved around three framing ideas or scenarios about the evolution of virtual environments: 1. Remote exploration: The ability to create high fidelity environments rendered from external data or models such that exploration, design and analysis that is truly interoperable with the physical world can take place within them. 2. We all get to go: The ability to engage anyone in being a part of or contributing to an experience (such as a space mission), no matter their training or location. It is the creation of a new paradigm for education, outreach, and the conduct of science in society that is truly participatory. 3. Become the data: A vision of a future where boundaries between the physical and the virtual have ceased to be meaningful. What would this future look like? Is this plausible? Is it desirable? Why and why not?

Comparing the cost-effectiveness of simulation modalities: a case study of peripheral intravenous catheterization training.

PubMed

Isaranuwatchai, Wanrudee; Brydges, Ryan; Carnahan, Heather; Backstein, David; Dubrowski, Adam

2014-05-01

While the ultimate goal of simulation training is to enhance learning, cost-effectiveness is a critical factor. Research that compares simulation training in terms of educational- and cost-effectiveness will lead to better-informed curricular decisions. Using previously published data we conducted a cost-effectiveness analysis of three simulation-based programs. Medical students (n = 15 per group) practiced in one of three 2-h intravenous catheterization skills training programs: low-fidelity (virtual reality), high-fidelity (mannequin), or progressive (consisting of virtual reality, task trainer, and mannequin simulator). One week later, all performed a transfer test on a hybrid simulation (standardized patient with a task trainer). We used a net benefit regression model to identify the most cost-effective training program via paired comparisons. We also created a cost-effectiveness acceptability curve to visually represent the probability that one program is more cost-effective when compared to its comparator at various 'willingness-to-pay' values. We conducted separate analyses for implementation and total costs. The results showed that the progressive program had the highest total cost (p < 0.001) whereas the high-fidelity program had the highest implementation cost (p < 0.001). While the most cost-effective program depended on the decision makers' willingness-to-pay value, the progressive training program was generally most educationally- and cost-effective. Our analyses suggest that a progressive program that strategically combines simulation modalities provides a cost-effective solution. More generally, we have introduced how a cost-effectiveness analysis may be applied to simulation training; a method that medical educators may use to investment decisions (e.g., purchasing cost-effective and educationally sound simulators).

Mission Simulation Facility: Simulation Support for Autonomy Development

NASA Technical Reports Server (NTRS)

Pisanich, Greg; Plice, Laura; Neukom, Christian; Flueckiger, Lorenzo; Wagner, Michael

2003-01-01

The Mission Simulation Facility (MSF) supports research in autonomy technology for planetary exploration vehicles. Using HLA (High Level Architecture) across distributed computers, the MSF connects users autonomy algorithms with provided or third-party simulations of robotic vehicles and planetary surface environments, including onboard components and scientific instruments. Simulation fidelity is variable to meet changing needs as autonomy technology advances in Technical Readiness Level (TRL). A virtual robot operating in a virtual environment offers numerous advantages over actual hardware, including availability, simplicity, and risk mitigation. The MSF is in use by researchers at NASA Ames Research Center (ARC) and has demonstrated basic functionality. Continuing work will support the needs of a broader user base.

High-fidelity simulation capability for virtual testing of seismic and acoustic sensors

NASA Astrophysics Data System (ADS)

Wilson, D. Keith; Moran, Mark L.; Ketcham, Stephen A.; Lacombe, James; Anderson, Thomas S.; Symons, Neill P.; Aldridge, David F.; Marlin, David H.; Collier, Sandra L.; Ostashev, Vladimir E.

2005-05-01

This paper describes development and application of a high-fidelity, seismic/acoustic simulation capability for battlefield sensors. The purpose is to provide simulated sensor data so realistic that they cannot be distinguished by experts from actual field data. This emerging capability provides rapid, low-cost trade studies of unattended ground sensor network configurations, data processing and fusion strategies, and signatures emitted by prototype vehicles. There are three essential components to the modeling: (1) detailed mechanical signature models for vehicles and walkers, (2) high-resolution characterization of the subsurface and atmospheric environments, and (3) state-of-the-art seismic/acoustic models for propagating moving-vehicle signatures through realistic, complex environments. With regard to the first of these components, dynamic models of wheeled and tracked vehicles have been developed to generate ground force inputs to seismic propagation models. Vehicle models range from simple, 2D representations to highly detailed, 3D representations of entire linked-track suspension systems. Similarly detailed models of acoustic emissions from vehicle engines are under development. The propagation calculations for both the seismics and acoustics are based on finite-difference, time-domain (FDTD) methodologies capable of handling complex environmental features such as heterogeneous geologies, urban structures, surface vegetation, and dynamic atmospheric turbulence. Any number of dynamic sources and virtual sensors may be incorporated into the FDTD model. The computational demands of 3D FDTD simulation over tactical distances require massively parallel computers. Several example calculations of seismic/acoustic wave propagation through complex atmospheric and terrain environments are shown.

A Fixed-Wing Aircraft Simulation Tool for Improving the efficiency of DoD Acquisition

DTIC Science & Technology

2015-10-05

simulation tool , CREATETM-AV Helios [12-14], a high fidelity rotary wing vehicle simulation tool , and CREATETM-AV DaVinci [15-16], a conceptual through...05/2015 Oct 2008-Sep 2015 A Fixed-Wing Aircraft Simulation Tool for Improving the Efficiency of DoD Acquisition Scott A. Morton and David R...multi-disciplinary fixed-wing virtual aircraft simulation tool incorporating aerodynamics, structural dynamics, kinematics, and kinetics. Kestrel allows

iSocial: delivering the Social Competence Intervention for Adolescents (SCI-A) in a 3D virtual learning environment for youth with high functioning autism.

PubMed

Stichter, Janine P; Laffey, James; Galyen, Krista; Herzog, Melissa

2014-02-01

One consistent area of need for students with autism spectrum disorders is in the area of social competence. However, the increasing need to provide qualified teachers to deliver evidence-based practices in areas like social competence leave schools, such as those found in rural areas, in need of support. Distance education and in particular, 3D Virtual Learning, holds great promise for supporting schools and youth to gain social competence through knowledge and social practice in context. iSocial, a distance education, 3D virtual learning environment implemented the 31-lesson social competence intervention for adolescents across three small cohorts totaling 11 students over a period of 4 months. Results demonstrated that the social competence curriculum was delivered with fidelity in the 3D virtual learning environment. Moreover, learning outcomes suggest that the iSocial approach shows promise for social competence benefits for youth.

Measuring Co-Presence and Social Presence in Virtual Environments - Psychometric Construction of a German Scale for a Fear of Public Speaking Scenario.

PubMed

Poeschl, Sandra; Doering, Nicola

2015-01-01

Virtual reality exposure therapy (VRET) applications use high levels of fidelity in order to produce high levels of presence and thereby elicit an emotional response for the user (like fear for phobia treatment). State of research shows mixed results for the correlation between anxiety and presence in virtual reality exposure, with differing results depending on specific anxiety disorders. A positive correlation for anxiety and presence for social anxiety disorder is not proven up to now. One reason might be that plausibility of the simulation, namely including key triggers for social anxiety (for example verbal and non-verbal behavior of virtual agents that reflects potentially negative human evaluation) might not be acknowledged in current presence questionnaires. A German scale for measuring co-presence and social presence for virtual reality (VR) fear of public speaking scenarios was developed based on a translation and adaption of existing co-presence and social presence questionnaires. A sample of N = 151 students rated co-presence and social presence after using a fear of public speaking application. Four correlated factors were derived by item- and principle axis factor analysis (Promax rotation), representing the presenter's reaction to virtual agents, the reactions of the virtual agents as perceived by the presenter, impression of interaction possibilities, and (co-)presence of other people in the virtual environment. The scale developed can be used as a starting point for future research and test construction for VR applications with a social context.

The use of high fidelity CAD models as the basis for training on complex systems

NASA Technical Reports Server (NTRS)

Miller, Kellie; Tanner, Steve

1993-01-01

During the design phases of large and complex systems such as NASA's Space Station Freedom (SSF), there are few, if any physical prototypes built. This is often due to their expense and the realization that the design is likely to change. This poses a problem for training, maintainability, and operations groups who are tasked to lay the foundation of plans for using these systems. The Virtual Reality and Visualization Laboratory at the Boeing Advanced Computing Group's Huntsville facility is supporting the use of high fidelity, detailed design models that are generated during the initial design phases, for use in training, maintainability and operations exercises. This capability was used in its non-immersive form to great effect at the SSF Critical Design Review (CDR) during February, 1993. Allowing the user to move about within a CAD design supports many efforts, including training and scenario study. We will demonstrate via a video of the Maintainability SSF CDR how this type of approach can be used and why it is so effective in conveying large amounts of information quickly and concisely. We will also demonstrate why high fidelity models are so important for this type of training system and how it's immersive aspects may be exploited as well.

The Avenor Virtual Trainer Project--A 3D Interactive Training Module on Energy Control Procedures: Development and First Validation Results.

ERIC Educational Resources Information Center

Giardina, Max

This paper examines the implementation of 3D simulation through the development of the Avenor Virtual Trainer and how situated learning and fidelity of model representation become the basis for more effective Interactive Multimedia Training Situations. The discussion will focus of some principles concerned with situated training, simulation,…

Efficiently Scheduling Multi-core Guest Virtual Machines on Multi-core Hosts in Network Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoginath, Srikanth B; Perumalla, Kalyan S

2011-01-01

Virtual machine (VM)-based simulation is a method used by network simulators to incorporate realistic application behaviors by executing actual VMs as high-fidelity surrogates for simulated end-hosts. A critical requirement in such a method is the simulation time-ordered scheduling and execution of the VMs. Prior approaches such as time dilation are less efficient due to the high degree of multiplexing possible when multiple multi-core VMs are simulated on multi-core host systems. We present a new simulation time-ordered scheduler to efficiently schedule multi-core VMs on multi-core real hosts, with a virtual clock realized on each virtual core. The distinguishing features of ourmore » approach are: (1) customizable granularity of the VM scheduling time unit on the simulation time axis, (2) ability to take arbitrary leaps in virtual time by VMs to maximize the utilization of host (real) cores when guest virtual cores idle, and (3) empirically determinable optimality in the tradeoff between total execution (real) time and time-ordering accuracy levels. Experiments show that it is possible to get nearly perfect time-ordered execution, with a slight cost in total run time, relative to optimized non-simulation VM schedulers. Interestingly, with our time-ordered scheduler, it is also possible to reduce the time-ordering error from over 50% of non-simulation scheduler to less than 1% realized by our scheduler, with almost the same run time efficiency as that of the highly efficient non-simulation VM schedulers.« less

High-Fidelity Roadway Modeling and Simulation

NASA Technical Reports Server (NTRS)

Wang, Jie; Papelis, Yiannis; Shen, Yuzhong; Unal, Ozhan; Cetin, Mecit

2010-01-01

Roads are an essential feature in our daily lives. With the advances in computing technologies, 2D and 3D road models are employed in many applications, such as computer games and virtual environments. Traditional road models were generated by professional artists manually using modeling software tools such as Maya and 3ds Max. This approach requires both highly specialized and sophisticated skills and massive manual labor. Automatic road generation based on procedural modeling can create road models using specially designed computer algorithms or procedures, reducing the tedious manual editing needed for road modeling dramatically. But most existing procedural modeling methods for road generation put emphasis on the visual effects of the generated roads, not the geometrical and architectural fidelity. This limitation seriously restricts the applicability of the generated road models. To address this problem, this paper proposes a high-fidelity roadway generation method that takes into account road design principles practiced by civil engineering professionals, and as a result, the generated roads can support not only general applications such as games and simulations in which roads are used as 3D assets, but also demanding civil engineering applications, which requires accurate geometrical models of roads. The inputs to the proposed method include road specifications, civil engineering road design rules, terrain information, and surrounding environment. Then the proposed method generates in real time 3D roads that have both high visual and geometrical fidelities. This paper discusses in details the procedures that convert 2D roads specified in shape files into 3D roads and civil engineering road design principles. The proposed method can be used in many applications that have stringent requirements on high precision 3D models, such as driving simulations and road design prototyping. Preliminary results demonstrate the effectiveness of the proposed method.

Evolving Storage and Cyber Infrastructure at the NASA Center for Climate Simulation

NASA Technical Reports Server (NTRS)

Salmon, Ellen; Duffy, Daniel; Spear, Carrie; Sinno, Scott; Vaughan, Garrison; Bowen, Michael

2018-01-01

This talk will describe recent developments at the NASA Center for Climate Simulation, which is funded by NASAs Science Mission Directorate, and supports the specialized data storage and computational needs of weather, ocean, and climate researchers, as well as astrophysicists, heliophysicists, and planetary scientists. To meet requirements for higher-resolution, higher-fidelity simulations, the NCCS augments its High Performance Computing (HPC) and storage retrieval environment. As the petabytes of model and observational data grow, the NCCS is broadening data services offerings and deploying and expanding virtualization resources for high performance analytics.

Comparison of the Efficacy and Efficiency of the Use of Virtual Reality Simulation With High-Fidelity Mannequins for Simulation-Based Training of Fiberoptic Bronchoscope Manipulation.

PubMed

Jiang, Bailin; Ju, Hui; Zhao, Ying; Yao, Lan; Feng, Yi

2018-04-01

This study compared the efficacy and efficiency of virtual reality simulation (VRS) with high-fidelity mannequin in the simulation-based training of fiberoptic bronchoscope manipulation in novices. Forty-six anesthesia residents with no experience in fiberoptic intubation were divided into two groups: VRS (group VRS) and mannequin (group M). After a standard didactic teaching session, group VRS trained 25 times on VRS, whereas group M performed the same process on a mannequin. After training, participants' performance was assessed on a mannequin five consecutive times. Procedure times during training were recorded as pooled data to construct learning curves. Procedure time and global rating scale scores of manipulation ability were compared between groups, as well as changes in participants' confidence after training. Plateaus in the learning curves were achieved after 19 (95% confidence interval = 15-26) practice sessions in group VRS and 24 (95% confidence interval = 20-32) in group M. There was no significant difference in procedure time [13.7 (6.6) vs. 11.9 (4.1) seconds, t' = 1.101, P = 0.278] or global rating scale [3.9 (0.4) vs. 3.8 (0.4), t = 0.791, P = 0.433] between groups. Participants' confidence increased after training [group VRS: 1.8 (0.7) vs. 3.9 (0.8), t = 8.321, P < 0.001; group M = 2.0 (0.7) vs. 4.0 (0.6), t = 13.948, P < 0.001] but did not differ significantly between groups. Virtual reality simulation is more efficient than mannequin in simulation-based training of flexible fiberoptic manipulation in novices, but similar effects can be achieved in both modalities after adequate training.

Headphone and Head-Mounted Visual Displays for Virtual Environments

NASA Technical Reports Server (NTRS)

Begault, Duran R.; Ellis, Stephen R.; Wenzel, Elizabeth M.; Trejo, Leonard J. (Technical Monitor)

1998-01-01

A realistic auditory environment can contribute to both the overall subjective sense of presence in a virtual display, and to a quantitative metric predicting human performance. Here, the role of audio in a virtual display and the importance of auditory-visual interaction are examined. Conjectures are proposed regarding the effectiveness of audio compared to visual information for creating a sensation of immersion, the frame of reference within a virtual display, and the compensation of visual fidelity by supplying auditory information. Future areas of research are outlined for improving simulations of virtual visual and acoustic spaces. This paper will describe some of the intersensory phenomena that arise during operator interaction within combined visual and auditory virtual environments. Conjectures regarding audio-visual interaction will be proposed.

Virtually-augmented interfaces for tactical aircraft.

PubMed

Haas, M W

1995-05-01

The term Fusion Interface is defined as a class of interface which integrally incorporates both virtual and non-virtual concepts and devices across the visual, auditory and haptic sensory modalities. A fusion interface is a multi-sensory virtually-augmented synthetic environment. A new facility has been developed within the Human Engineering Division of the Armstrong Laboratory dedicated to exploratory development of fusion-interface concepts. One of the virtual concepts to be investigated in the Fusion Interfaces for Tactical Environments facility (FITE) is the application of EEG and other physiological measures for virtual control of functions within the flight environment. FITE is a specialized flight simulator which allows efficient concept development through the use of rapid prototyping followed by direct experience of new fusion concepts. The FITE facility also supports evaluation of fusion concepts by operational fighter pilots in a high fidelity simulated air combat environment. The facility was utilized by a multi-disciplinary team composed of operational pilots, human-factors engineers, electronics engineers, computer scientists, and experimental psychologists to prototype and evaluate the first multi-sensory, virtually-augmented cockpit. The cockpit employed LCD-based head-down displays, a helmet-mounted display, three-dimensionally localized audio displays, and a haptic display. This paper will endeavor to describe the FITE facility architecture, some of the characteristics of the FITE virtual display and control devices, and the potential application of EEG and other physiological measures within the FITE facility.

High-Fidelity Modeling of Computer Network Worms

DTIC Science & Technology

2004-06-22

plots the propagation of the TCP-based worm. This execution is among the largest TCP worm models simulated to date at packet-level. TCP vs . UDP Worm...the mapping of the virtual IP addresses to honeyd’s MAC address in the proxy’s ARP table. The proxy server listens for packets from both sides of...experimental setup, we used two ntium-4 ThinkPad , and an IBM Pentium-III ThinkPad ), running the proxy server and honeyd respectively. The Code Red II worm

Eglin virtual range database for hardware-in-the-loop testing

NASA Astrophysics Data System (ADS)

Talele, Sunjay E.; Pickard, J. W., Jr.; Owens, Monte A.; Foster, Joseph; Watson, John S.; Amick, Mary Amenda; Anthony, Kenneth

1998-07-01

Realistic backgrounds are necessary to support high fidelity hardware-in-the-loop testing. Advanced avionics and weapon system sensors are driving the requirement for higher resolution imagery. The model-test-model philosophy being promoted by the T&E community is resulting in the need for backgrounds that are realistic or virtual representations of actual test areas. Combined, these requirements led to a major upgrade of the terrain database used for hardware-in-the-loop testing at the Guided Weapons Evaluation Facility (GWEF) at Eglin Air Force Base, Florida. This paper will describe the process used to generate the high-resolution (1-foot) database of ten sites totaling over 20 square kilometers of the Eglin range. this process involved generating digital elevation maps from stereo aerial imagery and classifying ground cover material using the spectral content. These databases were then optimized for real-time operation at 90 Hz.

VEDA: a web-based virtual environment for dynamic atomic force microscopy.

PubMed

Melcher, John; Hu, Shuiqing; Raman, Arvind

2008-06-01

We describe here the theory and applications of virtual environment dynamic atomic force microscopy (VEDA), a suite of state-of-the-art simulation tools deployed on nanoHUB (www.nanohub.org) for the accurate simulation of tip motion in dynamic atomic force microscopy (dAFM) over organic and inorganic samples. VEDA takes advantage of nanoHUB's cyberinfrastructure to run high-fidelity dAFM tip dynamics computations on local clusters and the teragrid. Consequently, these tools are freely accessible and the dAFM simulations are run using standard web-based browsers without requiring additional software. A wide range of issues in dAFM ranging from optimal probe choice, probe stability, and tip-sample interaction forces, power dissipation, to material property extraction and scanning dynamics over hetereogeneous samples can be addressed.

Invited Article: VEDA: A web-based virtual environment for dynamic atomic force microscopy

NASA Astrophysics Data System (ADS)

Melcher, John; Hu, Shuiqing; Raman, Arvind

2008-06-01

We describe here the theory and applications of virtual environment dynamic atomic force microscopy (VEDA), a suite of state-of-the-art simulation tools deployed on nanoHUB (www.nanohub.org) for the accurate simulation of tip motion in dynamic atomic force microscopy (dAFM) over organic and inorganic samples. VEDA takes advantage of nanoHUB's cyberinfrastructure to run high-fidelity dAFM tip dynamics computations on local clusters and the teragrid. Consequently, these tools are freely accessible and the dAFM simulations are run using standard web-based browsers without requiring additional software. A wide range of issues in dAFM ranging from optimal probe choice, probe stability, and tip-sample interaction forces, power dissipation, to material property extraction and scanning dynamics over hetereogeneous samples can be addressed.

Decoherence induced deformation of the ground state in adiabatic quantum computation.

PubMed

Deng, Qiang; Averin, Dmitri V; Amin, Mohammad H; Smith, Peter

2013-01-01

Despite more than a decade of research on adiabatic quantum computation (AQC), its decoherence properties are still poorly understood. Many theoretical works have suggested that AQC is more robust against decoherence, but a quantitative relation between its performance and the qubits' coherence properties, such as decoherence time, is still lacking. While the thermal excitations are known to be important sources of errors, they are predominantly dependent on temperature but rather insensitive to the qubits' coherence. Less understood is the role of virtual excitations, which can also reduce the ground state probability even at zero temperature. Here, we introduce normalized ground state fidelity as a measure of the decoherence-induced deformation of the ground state due to virtual transitions. We calculate the normalized fidelity perturbatively at finite temperatures and discuss its relation to the qubits' relaxation and dephasing times, as well as its projected scaling properties.

Decoherence induced deformation of the ground state in adiabatic quantum computation

PubMed Central

Deng, Qiang; Averin, Dmitri V.; Amin, Mohammad H.; Smith, Peter

2013-01-01

Despite more than a decade of research on adiabatic quantum computation (AQC), its decoherence properties are still poorly understood. Many theoretical works have suggested that AQC is more robust against decoherence, but a quantitative relation between its performance and the qubits' coherence properties, such as decoherence time, is still lacking. While the thermal excitations are known to be important sources of errors, they are predominantly dependent on temperature but rather insensitive to the qubits' coherence. Less understood is the role of virtual excitations, which can also reduce the ground state probability even at zero temperature. Here, we introduce normalized ground state fidelity as a measure of the decoherence-induced deformation of the ground state due to virtual transitions. We calculate the normalized fidelity perturbatively at finite temperatures and discuss its relation to the qubits' relaxation and dephasing times, as well as its projected scaling properties. PMID:23528821

Hierarchical control and performance evaluation of multi-vehicle autonomous systems

NASA Astrophysics Data System (ADS)

Balakirsky, Stephen; Scrapper, Chris; Messina, Elena

2005-05-01

This paper will describe how the Mobility Open Architecture Tools and Simulation (MOAST) framework can facilitate performance evaluations of RCS compliant multi-vehicle autonomous systems. This framework provides an environment that allows for simulated and real architectural components to function seamlessly together. By providing repeatable environmental conditions, this framework allows for the development of individual components as well as component performance metrics. MOAST is composed of high-fidelity and low-fidelity simulation systems, a detailed model of real-world terrain, actual hardware components, a central knowledge repository, and architectural glue to tie all of the components together. This paper will describe the framework"s components in detail and provide an example that illustrates how the framework can be utilized to develop and evaluate a single architectural component through the use of repeatable trials and experimentation that includes both virtual and real components functioning together

Simulation fidelity of a virtual environment display

NASA Technical Reports Server (NTRS)

Nemire, Kenneth; Jacoby, Richard H.; Ellis, Stephen R.

1994-01-01

We assessed the degree to which a virtual environment system produced a faithful simulation of three-dimensional space by investigating the influence of a pitched optic array on the perception of gravity-referenced eye level (GREL). We compared the results with those obtained in a physical environment. In a within-subjects factorial design, 12 subjects indicated GREL while viewing virtual three-dimensional arrays at different static orientations. A physical array biased GREL more than did a geometrically identical virtual pitched array. However, addition of two sets of orthogonal parallel lines (a grid) to the virtual pitched array resulted in as large a bias as that obtained with the physical pitched array. The increased bias was caused by longitudinal, but not the transverse, components of the grid. We discuss implications of our results for spatial orientation models and for designs of virtual displays.

A teleoperation training simulator with visual and kinesthetic force virtual reality

NASA Technical Reports Server (NTRS)

Kim, Won S.; Schenker, Paul

1992-01-01

A force-reflecting teleoperation training simulator with a high-fidelity real-time graphics display has been developed for operator training. A novel feature of this simulator is that it enables the operator to feel contact forces and torques through a force-reflecting controller during the execution of the simulated peg-in-hole task, providing the operator with the feel of visual and kinesthetic force virtual reality. A peg-in-hole task is used in our simulated teleoperation trainer as a generic teleoperation task. A quasi-static analysis of a two-dimensional peg-in-hole task model has been extended to a three-dimensional model analysis to compute contact forces and torques for a virtual realization of kinesthetic force feedback. The simulator allows the user to specify force reflection gains and stiffness (compliance) values of the manipulator hand for both the three translational and the three rotational axes in Cartesian space. Three viewing modes are provided for graphics display: single view, two split views, and stereoscopic view.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, Paul A.; Cooper, Candice Frances; Burnett, Damon J.

Light body armor development for the warfighter is based on trial-and-error testing of prototype designs against ballistic projectiles. Torso armor testing against blast is virtually nonexistent but necessary to ensure adequate protection against injury to the heart and lungs. In this report, we discuss the development of a high-fidelity human torso model, it's merging with the existing Sandia Human Head-Neck Model, and development of the modeling & simulation (M&S) capabilities necessary to simulate wound injury scenarios. Using the new Sandia Human Torso Model, we demonstrate the advantage of virtual simulation in the investigation of wound injury as it relates tomore » the warfighter experience. We present the results of virtual simulations of blast loading and ballistic projectile impact to the tors o with and without notional protective armor. In this manner, we demonstrate the ad vantages of applying a modeling and simulation approach to the investigation of wound injury and relative merit assessments of protective body armor without the need for trial-and-error testing.« less

Virtual Reality for Pediatric Sedation: A Randomized Controlled Trial Using Simulation.

PubMed

Zaveri, Pavan P; Davis, Aisha B; O'Connell, Karen J; Willner, Emily; Aronson Schinasi, Dana A; Ottolini, Mary

2016-02-09

Team training for procedural sedation for pediatric residents has traditionally consisted of didactic presentations and simulated scenarios using high-fidelity mannequins. We assessed the effectiveness of a virtual reality module in teaching preparation for and management of sedation for procedures. After developing a virtual reality environment in Second Life® (Linden Lab, San Francisco, CA) where providers perform and recover patients from procedural sedation, we conducted a randomized controlled trial to assess the effectiveness of the virtual reality module versus a traditional web-based educational module. A 20 question pre- and post-test was administered to assess knowledge change. All subjects participated in a simulated pediatric procedural sedation scenario that was video recorded for review and assessed using a 32-point checklist. A brief survey elicited feedback on the virtual reality module and the simulation scenario. The median score on the assessment checklist was 75% for the intervention group and 70% for the control group (P = 0.32). For the knowledge tests, there was no statistically significant difference between the groups (P = 0.14). Users had excellent reviews of the virtual reality module and reported that the module added to their education. Pediatric residents performed similarly in simulation and on a knowledge test after a virtual reality module compared with a traditional web-based module on procedural sedation. Although users enjoyed the virtual reality experience, these results question the value virtual reality adds in improving the performance of trainees. Further inquiry is needed into how virtual reality provides true value in simulation-based education.

Virtual Reality for Pediatric Sedation: A Randomized Controlled Trial Using Simulation

PubMed Central

Davis, Aisha B; O'Connell, Karen J; Willner, Emily; Aronson Schinasi, Dana A; Ottolini, Mary

2016-01-01

Introduction: Team training for procedural sedation for pediatric residents has traditionally consisted of didactic presentations and simulated scenarios using high-fidelity mannequins. We assessed the effectiveness of a virtual reality module in teaching preparation for and management of sedation for procedures. Methods: After developing a virtual reality environment in Second Life® (Linden Lab, San Francisco, CA) where providers perform and recover patients from procedural sedation, we conducted a randomized controlled trial to assess the effectiveness of the virtual reality module versus a traditional web-based educational module. A 20 question pre- and post-test was administered to assess knowledge change. All subjects participated in a simulated pediatric procedural sedation scenario that was video recorded for review and assessed using a 32-point checklist. A brief survey elicited feedback on the virtual reality module and the simulation scenario. Results: The median score on the assessment checklist was 75% for the intervention group and 70% for the control group (P = 0.32). For the knowledge tests, there was no statistically significant difference between the groups (P = 0.14). Users had excellent reviews of the virtual reality module and reported that the module added to their education. Conclusions: Pediatric residents performed similarly in simulation and on a knowledge test after a virtual reality module compared with a traditional web-based module on procedural sedation. Although users enjoyed the virtual reality experience, these results question the value virtual reality adds in improving the performance of trainees. Further inquiry is needed into how virtual reality provides true value in simulation-based education. PMID:27014520

Virtual/real transfer of spatial knowledge: benefit from visual fidelity provided in a virtual environment and impact of active navigation.

PubMed

Wallet, Grégory; Sauzéon, Hélène; Pala, Prashant Arvind; Larrue, Florian; Zheng, Xia; N'Kaoua, Bernard

2011-01-01

The purpose of this study was to evaluate the effect the visual fidelity of a virtual environment (VE) (undetailed vs. detailed) has on the transfer of spatial knowledge based on the navigation mode (passive vs. active) for three different spatial recall tasks (wayfinding, sketch mapping, and picture sorting). Sixty-four subjects (32 men and 32 women) participated in the experiment. Spatial learning was evaluated by these three tasks in the context of the Bordeaux district. In the wayfinding task, the results indicated that the detailed VE helped subjects to transfer their spatial knowledge from the VE to the real world, irrespective of the navigation mode. In the sketch-mapping task, the detailed VE increased performances compared to the undetailed VE condition, and allowed subjects to benefit from the active navigation. In the sorting task, performances were better in the detailed VE; however, in the undetailed version of the VE, active learning either did not help the subjects or it even deteriorated their performances. These results are discussed in terms of appropriate perceptive-motor and/or spatial representations for each spatial recall task.

Manipulating the fidelity of lower extremity visual feedback to identify obstacle negotiation strategies in immersive virtual reality.

PubMed

Kim, Aram; Zhou, Zixuan; Kretch, Kari S; Finley, James M

2017-07-01

The ability to successfully navigate obstacles in our environment requires integration of visual information about the environment with estimates of our body's state. Previous studies have used partial occlusion of the visual field to explore how information about the body and impending obstacles are integrated to mediate a successful clearance strategy. However, because these manipulations often remove information about both the body and obstacle, it remains to be seen how information about the lower extremities alone is utilized during obstacle crossing. Here, we used an immersive virtual reality (VR) interface to explore how visual feedback of the lower extremities influences obstacle crossing performance. Participants wore a head-mounted display while walking on treadmill and were instructed to step over obstacles in a virtual corridor in four different feedback trials. The trials involved: (1) No visual feedback of the lower extremities, (2) an endpoint-only model, (3) a link-segment model, and (4) a volumetric multi-segment model. We found that the volumetric model improved success rate, placed their trailing foot before crossing and leading foot after crossing more consistently, and placed their leading foot closer to the obstacle after crossing compared to no model. This knowledge is critical for the design of obstacle negotiation tasks in immersive virtual environments as it may provide information about the fidelity necessary to reproduce ecologically valid practice environments.

Modeling Quasi-Static and Fatigue-Driven Delamination Migration

NASA Technical Reports Server (NTRS)

De Carvalho, N. V.; Ratcliffe, J. G.; Chen, B. Y.; Pinho, S. T.; Baiz, P. M.; Tay, T. E.

2014-01-01

An approach was proposed and assessed for the high-fidelity modeling of progressive damage and failure in composite materials. It combines the Floating Node Method (FNM) and the Virtual Crack Closure Technique (VCCT) to represent multiple interacting failure mechanisms in a mesh-independent fashion. Delamination, matrix cracking, and migration were captured failure and migration criteria based on fracture mechanics. Quasi-static and fatigue loading were modeled within the same overall framework. The methodology proposed was illustrated by simulating the delamination migration test, showing good agreement with the available experimental data.

Height effects in real and virtual environments.

PubMed

Simeonov, Peter I; Hsiao, Hongwei; Dotson, Brian W; Ammons, Douglas E

2005-01-01

The study compared human perceptions of height, danger, and anxiety, as well as skin conductance and heart rate responses and postural instability effects, in real and virtual height environments. The 24 participants (12 men, 12 women), whose average age was 23.6 years, performed "lean-over-the-railing" and standing tasks on real and comparable virtual balconies, using a surround-screen virtual reality (SSVR) system. The results indicate that the virtual display of elevation provided realistic perceptual experience and induced some physiological responses and postural instability effects comparable to those found in a real environment. It appears that a simulation of elevated work environment in a SSVR system, although with reduced visual fidelity, is a valid tool for safety research. Potential applications of this study include the design of virtual environments that will help in safe evaluation of human performance at elevation, identification of risk factors leading to fall incidents, and assessment of new fall prevention strategies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayes, Birchard P; Michel, Kelly D; Few, Douglas A

From stereophonic, positional sound to high-definition imagery that is crisp and clean, high fidelity computer graphics enhance our view, insight, and intuition regarding our environments and conditions. Contemporary 3-D modeling tools offer an open architecture framework that enables integration with other technologically innovative arenas. One innovation of great interest is Augmented Reality, the merging of virtual, digital environments with physical, real-world environments creating a mixed reality where relevant data and information augments the real or actual experience in real-time by spatial or semantic context. Pairing 3-D virtual immersive models with a dynamic platform such as semi-autonomous robotics or personnel odometrymore » systems to create a mixed reality offers a new and innovative design information verification inspection capability, evaluation accuracy, and information gathering capability for nuclear facilities. Our paper discusses the integration of two innovative technologies, 3-D visualizations with inertial positioning systems, and the resulting augmented reality offered to the human inspector. The discussion in the paper includes an exploration of human and non-human (surrogate) inspections of a nuclear facility, integrated safeguards knowledge within a synchronized virtual model operated, or worn, by a human inspector, and the anticipated benefits to safeguards evaluations of facility operations.« less

A systematic review of phacoemulsification cataract surgery in virtual reality simulators.

PubMed

Lam, Chee Kiang; Sundaraj, Kenneth; Sulaiman, Mohd Nazri

2013-01-01

The aim of this study was to review the capability of virtual reality simulators in the application of phacoemulsification cataract surgery training. Our review included the scientific publications on cataract surgery simulators that had been developed by different groups of researchers along with commercialized surgical training products, such as EYESI® and PhacoVision®. The review covers the simulation of the main cataract surgery procedures, i.e., corneal incision, capsulorrhexis, phacosculpting, and intraocular lens implantation in various virtual reality surgery simulators. Haptics realism and visual realism of the procedures are the main elements in imitating the actual surgical environment. The involvement of ophthalmology in research on virtual reality since the early 1990s has made a great impact on the development of surgical simulators. Most of the latest cataract surgery training systems are able to offer high fidelity in visual feedback and haptics feedback, but visual realism, such as the rotational movements of an eyeball with response to the force applied by surgical instruments, is still lacking in some of them. The assessment of the surgical tasks carried out on the simulators showed a significant difference in the performance before and after the training.

Design of virtual simulation experiment based on key events

NASA Astrophysics Data System (ADS)

Zhong, Zheng; Zhou, Dongbo; Song, Lingxiu

2018-06-01

Considering complex content and lacking of guidance in virtual simulation experiments, the key event technology in VR narrative theory was introduced for virtual simulation experiment to enhance fidelity and vividness process. Based on the VR narrative technology, an event transition structure was designed to meet the need of experimental operation process, and an interactive event processing model was used to generate key events in interactive scene. The experiment of" margin value of bees foraging" based on Biologic morphology was taken as an example, many objects, behaviors and other contents were reorganized. The result shows that this method can enhance the user's experience and ensure experimental process complete and effectively.

minimega v. 3.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crussell, Jonathan; Erickson, Jeremy; Fritz, David

minimega is an emulytics platform for creating testbeds of networked devices. The platoform consists of easily deployable tools to facilitate bringing up large networks of virtual machines including Windows, Linux, and Android. minimega allows experiments to be brought up quickly with almost no configuration. minimega also includes tools for simple cluster, management, as well as tools for creating Linux-based virtual machines. This release of minimega includes new emulated sensors for Android devices to improve the fidelity of testbeds that include mobile devices. Emulated sensors include GPS and

Immersive virtual reality for visualization of abdominal CT

NASA Astrophysics Data System (ADS)

Lin, Qiufeng; Xu, Zhoubing; Li, Bo; Baucom, Rebeccah; Poulose, Benjamin; Landman, Bennett A.; Bodenheimer, Robert E.

2013-03-01

Immersive virtual environments use a stereoscopic head-mounted display and data glove to create high fidelity virtual experiences in which users can interact with three-dimensional models and perceive relationships at their true scale. This stands in stark contrast to traditional PACS-based infrastructure in which images are viewed as stacks of two dimensional slices, or, at best, disembodied renderings. Although there has substantial innovation in immersive virtual environments for entertainment and consumer media, these technologies have not been widely applied in clinical applications. Here, we consider potential applications of immersive virtual environments for ventral hernia patients with abdominal computed tomography imaging data. Nearly a half million ventral hernias occur in the United States each year, and hernia repair is the most commonly performed general surgery operation worldwide. A significant problem in these conditions is communicating the urgency, degree of severity, and impact of a hernia (and potential repair) on patient quality of life. Hernias are defined by ruptures in the abdominal wall (i.e., the absence of healthy tissues) rather than a growth (e.g., cancer); therefore, understanding a hernia necessitates understanding the entire abdomen. Our environment allows surgeons and patients to view body scans at scale and interact with these virtual models using a data glove. This visualization and interaction allows users to perceive the relationship between physical structures and medical imaging data. The system provides close integration of PACS-based CT data with immersive virtual environments and creates opportunities to study and optimize interfaces for patient communication, operative planning, and medical education.

Immersive Virtual Reality for Visualization of Abdominal CT.

PubMed

Lin, Qiufeng; Xu, Zhoubing; Li, Bo; Baucom, Rebeccah; Poulose, Benjamin; Landman, Bennett A; Bodenheimer, Robert E

2013-03-28

Immersive virtual environments use a stereoscopic head-mounted display and data glove to create high fidelity virtual experiences in which users can interact with three-dimensional models and perceive relationships at their true scale. This stands in stark contrast to traditional PACS-based infrastructure in which images are viewed as stacks of two-dimensional slices, or, at best, disembodied renderings. Although there has substantial innovation in immersive virtual environments for entertainment and consumer media, these technologies have not been widely applied in clinical applications. Here, we consider potential applications of immersive virtual environments for ventral hernia patients with abdominal computed tomography imaging data. Nearly a half million ventral hernias occur in the United States each year, and hernia repair is the most commonly performed general surgery operation worldwide. A significant problem in these conditions is communicating the urgency, degree of severity, and impact of a hernia (and potential repair) on patient quality of life. Hernias are defined by ruptures in the abdominal wall (i.e., the absence of healthy tissues) rather than a growth (e.g., cancer); therefore, understanding a hernia necessitates understanding the entire abdomen. Our environment allows surgeons and patients to view body scans at scale and interact with these virtual models using a data glove. This visualization and interaction allows users to perceive the relationship between physical structures and medical imaging data. The system provides close integration of PACS-based CT data with immersive virtual environments and creates opportunities to study and optimize interfaces for patient communication, operative planning, and medical education.

Exploring the use of high-fidelity simulation training to enhance clinical skills.

PubMed

Ann Kirkham, Lucy

2018-02-07

The use of interprofessional simulation training to enhance nursing students' performance of technical and non-technical clinical skills is becoming increasingly common. Simulation training can involve the use of role play, virtual reality or patient simulator manikins to replicate clinical scenarios and assess the nursing student's ability to, for example, undertake clinical observations or work as part of a team. Simulation training enables nursing students to practise clinical skills in a safe environment. Effective simulation training requires extensive preparation, and debriefing is necessary following a simulated training session to review any positive or negative aspects of the learning experience. This article discusses a high-fidelity simulated training session that was used to assess a group of third-year nursing students and foundation level 1 medical students. This involved the use of a patient simulator manikin in a scenario that required the collaborative management of a deteriorating patient. ©2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

High fidelity wireless network evaluation for heterogeneous cognitive radio networks

NASA Astrophysics Data System (ADS)

Ding, Lei; Sagduyu, Yalin; Yackoski, Justin; Azimi-Sadjadi, Babak; Li, Jason; Levy, Renato; Melodia, Tammaso

2012-06-01

We present a high fidelity cognitive radio (CR) network emulation platform for wireless system tests, measure- ments, and validation. This versatile platform provides the configurable functionalities to control and repeat realistic physical channel effects in integrated space, air, and ground networks. We combine the advantages of scalable simulation environment with reliable hardware performance for high fidelity and repeatable evaluation of heterogeneous CR networks. This approach extends CR design only at device (software-defined-radio) or lower-level protocol (dynamic spectrum access) level to end-to-end cognitive networking, and facilitates low-cost deployment, development, and experimentation of new wireless network protocols and applications on frequency- agile programmable radios. Going beyond the channel emulator paradigm for point-to-point communications, we can support simultaneous transmissions by network-level emulation that allows realistic physical-layer inter- actions between diverse user classes, including secondary users, primary users, and adversarial jammers in CR networks. In particular, we can replay field tests in a lab environment with real radios perceiving and learning the dynamic environment thereby adapting for end-to-end goals over distributed spectrum coordination channels that replace the common control channel as a single point of failure. CR networks offer several dimensions of tunable actions including channel, power, rate, and route selection. The proposed network evaluation platform is fully programmable and can reliably evaluate the necessary cross-layer design solutions with configurable op- timization space by leveraging the hardware experiments to represent the realistic effects of physical channel, topology, mobility, and jamming on spectrum agility, situational awareness, and network resiliency. We also provide the flexibility to scale up the test environment by introducing virtual radios and establishing seamless signal-level interactions with real radios. This holistic wireless evaluation approach supports a large-scale, het- erogeneous, and dynamic CR network architecture and allows developing cross-layer network protocols under high fidelity, repeatable, and scalable wireless test scenarios suitable for heterogeneous space, air, and ground networks.

A cost effective and high fidelity fluoroscopy simulator using the Image-Guided Surgery Toolkit (IGSTK)

NASA Astrophysics Data System (ADS)

Gong, Ren Hui; Jenkins, Brad; Sze, Raymond W.; Yaniv, Ziv

2014-03-01

The skills required for obtaining informative x-ray fluoroscopy images are currently acquired while trainees provide clinical care. As a consequence, trainees and patients are exposed to higher doses of radiation. Use of simulation has the potential to reduce this radiation exposure by enabling trainees to improve their skills in a safe environment prior to treating patients. We describe a low cost, high fidelity, fluoroscopy simulation system. Our system enables operators to practice their skills using the clinical device and simulated x-rays of a virtual patient. The patient is represented using a set of temporal Computed Tomography (CT) images, corresponding to the underlying dynamic processes. Simulated x-ray images, digitally reconstructed radiographs (DRRs), are generated from the CTs using ray-casting with customizable machine specific imaging parameters. To establish the spatial relationship between the CT and the fluoroscopy device, the CT is virtually attached to a patient phantom and a web camera is used to track the phantom's pose. The camera is mounted on the fluoroscope's intensifier and the relationship between it and the x-ray source is obtained via calibration. To control image acquisition the operator moves the fluoroscope as in normal operation mode. Control of zoom, collimation and image save is done using a keypad mounted alongside the device's control panel. Implementation is based on the Image-Guided Surgery Toolkit (IGSTK), and the use of the graphics processing unit (GPU) for accelerated image generation. Our system was evaluated by 11 clinicians and was found to be sufficiently realistic for training purposes.

The visible ear simulator: a public PC application for GPU-accelerated haptic 3D simulation of ear surgery based on the visible ear data.

PubMed

Sorensen, Mads Solvsten; Mosegaard, Jesper; Trier, Peter

2009-06-01

Existing virtual simulators for middle ear surgery are based on 3-dimensional (3D) models from computed tomographic or magnetic resonance imaging data in which image quality is limited by the lack of detail (maximum, approximately 50 voxels/mm3), natural color, and texture of the source material.Virtual training often requires the purchase of a program, a customized computer, and expensive peripherals dedicated exclusively to this purpose. The Visible Ear freeware library of digital images from a fresh-frozen human temporal bone was segmented, and real-time volume rendered as a 3D model of high-fidelity, true color, and great anatomic detail and realism of the surgically relevant structures. A haptic drilling model was developed for surgical interaction with the 3D model. Realistic visualization in high-fidelity (approximately 125 voxels/mm3) and true color, 2D, or optional anaglyph stereoscopic 3D was achieved on a standard Core 2 Duo personal computer with a GeForce 8,800 GTX graphics card, and surgical interaction was provided through a relatively inexpensive (approximately $2,500) Phantom Omni haptic 3D pointing device. This prototype is published for download (approximately 120 MB) as freeware at http://www.alexandra.dk/ves/index.htm.With increasing personal computer performance, future versions may include enhanced resolution (up to 8,000 voxels/mm3) and realistic interaction with deformable soft tissue components such as skin, tympanic membrane, dura, and cholesteatomas-features some of which are not possible with computed tomographic-/magnetic resonance imaging-based systems.

An investigation of the efficacy of collaborative virtual reality systems for moderated remote usability testing.

PubMed

Chalil Madathil, Kapil; Greenstein, Joel S

2017-11-01

Collaborative virtual reality-based systems have integrated high fidelity voice-based communication, immersive audio and screen-sharing tools into virtual environments. Such three-dimensional collaborative virtual environments can mirror the collaboration among usability test participants and facilitators when they are physically collocated, potentially enabling moderated usability tests to be conducted effectively when the facilitator and participant are located in different places. We developed a virtual collaborative three-dimensional remote moderated usability testing laboratory and employed it in a controlled study to evaluate the effectiveness of moderated usability testing in a collaborative virtual reality-based environment with two other moderated usability testing methods: the traditional lab approach and Cisco WebEx, a web-based conferencing and screen sharing approach. Using a mixed methods experimental design, 36 test participants and 12 test facilitators were asked to complete representative tasks on a simulated online shopping website. The dependent variables included the time taken to complete the tasks; the usability defects identified and their severity; and the subjective ratings on the workload index, presence and satisfaction questionnaires. Remote moderated usability testing methodology using a collaborative virtual reality system performed similarly in terms of the total number of defects identified, the number of high severity defects identified and the time taken to complete the tasks with the other two methodologies. The overall workload experienced by the test participants and facilitators was the least with the traditional lab condition. No significant differences were identified for the workload experienced with the virtual reality and the WebEx conditions. However, test participants experienced greater involvement and a more immersive experience in the virtual environment than in the WebEx condition. The ratings for the virtual environment condition were not significantly different from those for the traditional lab condition. The results of this study suggest that participants were productive and enjoyed the virtual lab condition, indicating the potential of a virtual world based approach as an alternative to conventional approaches for synchronous usability testing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Megatux

DOE Office of Scientific and Technical Information (OSTI.GOV)

2012-09-25

The Megatux platform enables the emulation of large scale (multi-million node) distributed systems. In particular, it allows for the emulation of large-scale networks interconnecting a very large number of emulated computer systems. It does this by leveraging virtualization and associated technologies to allow hundreds of virtual computers to be hosted on a single moderately sized server or workstation. Virtualization technology provided by modern processors allows for multiple guest OSs to run at the same time, sharing the hardware resources. The Megatux platform can be deployed on a single PC, a small cluster of a few boxes or a large clustermore » of computers. With a modest cluster, the Megatux platform can emulate complex organizational networks. By using virtualization, we emulate the hardware, but run actual software enabling large scale without sacrificing fidelity.« less

VIPER: Virtual Intelligent Planetary Exploration Rover

NASA Technical Reports Server (NTRS)

Edwards, Laurence; Flueckiger, Lorenzo; Nguyen, Laurent; Washington, Richard

2001-01-01

Simulation and visualization of rover behavior are critical capabilities for scientists and rover operators to construct, test, and validate plans for commanding a remote rover. The VIPER system links these capabilities. using a high-fidelity virtual-reality (VR) environment. a kinematically accurate simulator, and a flexible plan executive to allow users to simulate and visualize possible execution outcomes of a plan under development. This work is part of a larger vision of a science-centered rover control environment, where a scientist may inspect and explore the environment via VR tools, specify science goals, and visualize the expected and actual behavior of the remote rover. The VIPER system is constructed from three generic systems, linked together via a minimal amount of customization into the integrated system. The complete system points out the power of combining plan execution, simulation, and visualization for envisioning rover behavior; it also demonstrates the utility of developing generic technologies. which can be combined in novel and useful ways.

Conformation guides molecular efficacy in docking screens of activated β-2 adrenergic G protein coupled receptor.

PubMed

Weiss, Dahlia R; Ahn, SeungKirl; Sassano, Maria F; Kleist, Andrew; Zhu, Xiao; Strachan, Ryan; Roth, Bryan L; Lefkowitz, Robert J; Shoichet, Brian K

2013-05-17

A prospective, large library virtual screen against an activated β2-adrenergic receptor (β2AR) structure returned potent agonists to the exclusion of inverse-agonists, providing the first complement to the previous virtual screening campaigns against inverse-agonist-bound G protein coupled receptor (GPCR) structures, which predicted only inverse-agonists. In addition, two hits recapitulated the signaling profile of the co-crystal ligand with respect to the G protein and arrestin mediated signaling. This functional fidelity has important implications in drug design, as the ability to predict ligands with predefined signaling properties is highly desirable. However, the agonist-bound state provides an uncertain template for modeling the activated conformation of other GPCRs, as a dopamine D2 receptor (DRD2) activated model templated on the activated β2AR structure returned few hits of only marginal potency.

Synthetic Vision System Commercial Aircraft Flight Deck Display Technologies for Unusual Attitude Recovery

NASA Technical Reports Server (NTRS)

Prinzel, Lawrence J., III; Ellis, Kyle E.; Arthur, Jarvis J.; Nicholas, Stephanie N.; Kiggins, Daniel

2017-01-01

A Commercial Aviation Safety Team (CAST) study of 18 worldwide loss-of-control accidents and incidents determined that the lack of external visual references was associated with a flight crew's loss of attitude awareness or energy state awareness in 17 of these events. Therefore, CAST recommended development and implementation of virtual day-Visual Meteorological Condition (VMC) display systems, such as synthetic vision systems, which can promote flight crew attitude awareness similar to a day-VMC environment. This paper describes the results of a high-fidelity, large transport aircraft simulation experiment that evaluated virtual day-VMC displays and a "background attitude indicator" concept as an aid to pilots in recovery from unusual attitudes. Twelve commercial airline pilots performed multiple unusual attitude recoveries and both quantitative and qualitative dependent measures were collected. Experimental results and future research directions under this CAST initiative and the NASA "Technologies for Airplane State Awareness" research project are described.

Three-dimensional-printed gas dynamic virtual nozzles for x-ray laser sample delivery

PubMed Central

Nelson, Garrett; Kirian, Richard A.; Weierstall, Uwe; Zatsepin, Nadia A.; Faragó, Tomáš; Baumbach, Tilo; Wilde, Fabian; Niesler, Fabian B. P.; Zimmer, Benjamin; Ishigami, Izumi; Hikita, Masahide; Bajt, Saša; Yeh, Syun-Ru; Rousseau, Denis L.; Chapman, Henry N.; Spence, John C. H.; Heymann, Michael

2016-01-01

Reliable sample delivery is essential to biological imaging using X-ray Free Electron Lasers (XFELs). Continuous injection using the Gas Dynamic Virtual Nozzle (GDVN) has proven valuable, particularly for time-resolved studies. However, many important aspects of GDVN functionality have yet to be thoroughly understood and/or refined due to fabrication limitations. We report the application of 2-photon polymerization as a form of high-resolution 3D printing to fabricate high-fidelity GDVNs with submicron resolution. This technique allows rapid prototyping of a wide range of different types of nozzles from standard CAD drawings and optimization of crucial dimensions for optimal performance. Three nozzles were tested with pure water to determine general nozzle performance and reproducibility, with nearly reproducible off-axis jetting being the result. X-ray tomography and index matching were successfully used to evaluate the interior nozzle structures and identify the cause of off-axis jetting. Subsequent refinements to fabrication resulted in straight jetting. A performance test of printed nozzles at an XFEL provided high quality femtosecond diffraction patterns. PMID:27410079

Shoulder Kinematics and Spatial Pattern of Trapezius Electromyographic Activity in Real and Virtual Environments

PubMed Central

Samani, Afshin; Pontonnier, Charles; Dumont, Georges; Madeleine, Pascal

2015-01-01

The design of an industrial workstation tends to include ergonomic assessment steps based on a digital mock-up and a virtual reality setup. Lack of interaction and system fidelity is often reported as a main issue in such virtual reality applications. This limitation is a crucial issue as thorough ergonomic analysis is required for an investigation of the biomechanics. In the current study, we investigated the biomechanical responses of the shoulder joint in a simulated assembly task for comparison with the biomechanical responses in virtual environments. Sixteen male healthy novice subjects performed the task on three different platforms: real (RE), virtual (VE), and virtual environment with force feedback (VEF) with low and high precision demands. The subjects repeated the task 12 times (i.e., 12 cycles). High density electromyography from the upper trapezius and rotation angles of the shoulder joint were recorded and split into the cycles. The angular trajectories and velocity profiles of the shoulder joint angles over a cycle were computed in 3D. The inter-subject similarity in terms of normalized mutual information on kinematics and electromyography was investigated. Compared with RE the task in VE and VEF was characterized by lower kinematic maxima. The inter-subject similarity in RE compared with intra-subject similarity across the platforms was lower in terms of movement trajectories and greater in terms of trapezius muscle activation. The precision demand resulted in lower inter- and intra-subject similarity across platforms. The proposed approach identifies biomechanical differences in the shoulder joint in both VE and VEF compared with the RE platform, but these differences are less marked in VE mostly due to technical limitations of co-localizing the force feedback system in the VEF platform. PMID:25768123

Virtual Instrument Simulator for CERES

NASA Technical Reports Server (NTRS)

Chapman, John J.

1997-01-01

A benchtop virtual instrument simulator for CERES (Clouds and the Earth's Radiant Energy System) has been built at NASA, Langley Research Center in Hampton, VA. The CERES instruments will fly on several earth orbiting platforms notably NASDA's Tropical Rainfall Measurement Mission (TRMM) and NASA's Earth Observing System (EOS) satellites. CERES measures top of the atmosphere radiative fluxes using microprocessor controlled scanning radiometers. The CERES Virtual Instrument Simulator consists of electronic circuitry identical to the flight unit's twin microprocessors and telemetry interface to the supporting spacecraft electronics and two personal computers (PC) connected to the I/O ports that control azimuth and elevation gimbals. Software consists of the unmodified TRW developed Flight Code and Ground Support Software which serves as the instrument monitor and NASA/TRW developed engineering models of the scanners. The CERES Instrument Simulator will serve as a testbed for testing of custom instrument commands intended to solve in-flight anomalies of the instruments which could arise during the CERES mission. One of the supporting computers supports the telemetry display which monitors the simulator microprocessors during the development and testing of custom instrument commands. The CERES engineering development software models have been modified to provide a virtual instrument running on a second supporting computer linked in real time to the instrument flight microprocessor control ports. The CERES Instrument Simulator will be used to verify memory uploads by the CERES Flight Operations TEAM at NASA. Plots of the virtual scanner models match the actual instrument scan plots. A high speed logic analyzer has been used to track the performance of the flight microprocessor. The concept of using an identical but non-flight qualified microprocessor and electronics ensemble linked to a virtual instrument with identical system software affords a relatively inexpensive simulation system capable of high fidelity.

The effect of visual and interaction fidelity on spatial cognition in immersive virtual environments.

PubMed

Mania, Katerina; Wooldridge, Dave; Coxon, Matthew; Robinson, Andrew

2006-01-01

Accuracy of memory performance per se is an imperfect reflection of the cognitive activity (awareness states) that underlies performance in memory tasks. The aim of this research is to investigate the effect of varied visual and interaction fidelity of immersive virtual environments on memory awareness states. A between groups experiment was carried out to explore the effect of rendering quality on location-based recognition memory for objects and associated states of awareness. The experimental space, consisting of two interconnected rooms, was rendered either flat-shaded or using radiosity rendering. The computer graphics simulations were displayed on a stereo head-tracked Head Mounted Display. Participants completed a recognition memory task after exposure to the experimental space and reported one of four states of awareness following object recognition. These reflected the level of visual mental imagery involved during retrieval, the familiarity of the recollection, and also included guesses. Experimental results revealed variations in the distribution of participants' awareness states across conditions while memory performance failed to reveal any. Interestingly, results revealed a higher proportion of recollections associated with mental imagery in the flat-shaded condition. These findings comply with similar effects revealed in two earlier studies summarized here, which demonstrated that the less "naturalistic" interaction interface or interface of low interaction fidelity provoked a higher proportion of recognitions based on visual mental images.

A review of virtual reality based training simulators for orthopaedic surgery.

PubMed

Vaughan, Neil; Dubey, Venketesh N; Wainwright, Thomas W; Middleton, Robert G

2016-02-01

This review presents current virtual reality based training simulators for hip, knee and other orthopaedic surgery, including elective and trauma surgical procedures. There have not been any reviews focussing on hip and knee orthopaedic simulators. A comparison of existing simulator features is provided to identify what is missing and what is required to improve upon current simulators. In total 11 hip replacements pre-operative planning tools were analysed, plus 9 hip trauma fracture training simulators. Additionally 9 knee arthroscopy simulators and 8 other orthopaedic simulators were included for comparison. The findings are that for orthopaedic surgery simulators in general, there is increasing use of patient-specific virtual models which reduce the learning curve. Modelling is also being used for patient-specific implant design and manufacture. Simulators are being increasingly validated for assessment as well as training. There are very few training simulators available for hip replacement, yet more advanced virtual reality is being used for other procedures such as hip trauma and drilling. Training simulators for hip replacement and orthopaedic surgery in general lag behind other surgical procedures for which virtual reality has become more common. Further developments are required to bring hip replacement training simulation up to date with other procedures. This suggests there is a gap in the market for a new high fidelity hip replacement and resurfacing training simulator. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Use of a Virtual Learning Platform for Distance-Based Simulation in an Acute Care Nurse Practitioner Curriculum.

PubMed

Carman, Margaret; Xu, Shu; Rushton, Sharron; Smallheer, Benjamin A; Williams, Denise; Amarasekara, Sathya; Oermann, Marilyn H

Acute care nurse practitioner (ACNP) programs that use high-fidelity simulation as a teaching tool need to consider innovative strategies to provide distance-based students with learning experiences that are comparable to those in a simulation laboratory. The purpose of this article is to describe the use of virtual simulations in a distance-based ACNP program and student performance in the simulations. Virtual simulations using iSimulate were integrated into the ACNP course to promote the translation of content into a clinical context and enable students to develop their knowledge and decision-making skills. With these simulations, students worked as a team, even though they were at different sites from each other and from the faculty, to manage care of an acutely ill patient. The students were assigned to simulation groups of 4 students each. One week before the simulation, they reviewed past medical records. The virtual simulation sessions were recorded and then evaluated. The evaluation tools assessed 8 areas of performance and included key behaviors in each of these areas to be performed by students in the simulation. More than 80% of the student groups performed the key behaviors. Virtual simulations provide a learning platform that allows live interaction between students and faculty, at a distance, and application of content to clinical situations. With simulation, learners have an opportunity to practice assessment and decision-making in emergency and high-risk situations. Simulations not only are valuable for student learning but also provide a nonthreatening environment for staff to practice, receive feedback on their skills, and improve their confidence.

Development of the McGill simulator for endoscopic sinus surgery: a new high-fidelity virtual reality simulator for endoscopic sinus surgery.

PubMed

Varshney, Rickul; Frenkiel, Saul; Nguyen, Lily H P; Young, Meredith; Del Maestro, Rolando; Zeitouni, Anthony; Tewfik, Marc A

2014-01-01

The technical challenges of endoscopic sinus surgery (ESS) and the high risk of complications support the development of alternative modalities to train residents in these procedures. Virtual reality simulation is becoming a useful tool for training the skills necessary for minimally invasive surgery; however, there are currently no ESS virtual reality simulators available with valid evidence supporting their use in resident education. Our aim was to develop a new rhinology simulator, as well as to define potential performance metrics for trainee assessment. The McGill simulator for endoscopic sinus surgery (MSESS), a new sinus surgery virtual reality simulator with haptic feedback, was developed (a collaboration between the McGill University Department of Otolaryngology-Head and Neck Surgery, the Montreal Neurologic Institute Simulation Lab, and the National Research Council of Canada). A panel of experts in education, performance assessment, rhinology, and skull base surgery convened to identify core technical abilities that would need to be taught by the simulator, as well as performance metrics to be developed and captured. The MSESS allows the user to perform basic sinus surgery skills, such as an ethmoidectomy and sphenoidotomy, through the use of endoscopic tools in a virtual nasal model. The performance metrics were developed by an expert panel and include measurements of safety, quality, and efficiency of the procedure. The MSESS incorporates novel technological advancements to create a realistic platform for trainees. To our knowledge, this is the first simulator to combine novel tools such as the endonasal wash and elaborate anatomic deformity with advanced performance metrics for ESS.

Modelling Human Emotions for Tactical Decision-Making Games

ERIC Educational Resources Information Center

Visschedijk, Gillian C.; Lazonder, Ard W.; van der Hulst, Anja; Vink, Nathalie; Leemkuil, Henny

2013-01-01

The training of tactical decision making increasingly occurs through serious computer games. A challenging aspect of designing such games is the modelling of human emotions. Two studies were performed to investigate the relation between fidelity and human emotion recognition in virtual human characters. Study 1 compared five versions of a virtual…

Procedural wound geometry and blood flow generation for medical training simulators

NASA Astrophysics Data System (ADS)

Aras, Rifat; Shen, Yuzhong; Li, Jiang

2012-02-01

Efficient application of wound treatment procedures is vital in both emergency room and battle zone scenes. In order to train first responders for such situations, physical casualty simulation kits, which are composed of tens of individual items, are commonly used. Similar to any other training scenarios, computer simulations can be effective means for wound treatment training purposes. For immersive and high fidelity virtual reality applications, realistic 3D models are key components. However, creation of such models is a labor intensive process. In this paper, we propose a procedural wound geometry generation technique that parameterizes key simulation inputs to establish the variability of the training scenarios without the need of labor intensive remodeling of the 3D geometry. The procedural techniques described in this work are entirely handled by the graphics processing unit (GPU) to enable interactive real-time operation of the simulation and to relieve the CPU for other computational tasks. The visible human dataset is processed and used as a volumetric texture for the internal visualization of the wound geometry. To further enhance the fidelity of the simulation, we also employ a surface flow model for blood visualization. This model is realized as a dynamic texture that is composed of a height field and a normal map and animated at each simulation step on the GPU. The procedural wound geometry and the blood flow model are applied to a thigh model and the efficiency of the technique is demonstrated in a virtual surgery scene.

Taming Wild Horses: The Need for Virtual Time-based Scheduling of VMs in Network Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoginath, Srikanth B; Perumalla, Kalyan S; Henz, Brian J

2012-01-01

The next generation of scalable network simulators employ virtual machines (VMs) to act as high-fidelity models of traffic producer/consumer nodes in simulated networks. However, network simulations could be inaccurate if VMs are not scheduled according to virtual time, especially when many VMs are hosted per simulator core in a multi-core simulator environment. Since VMs are by default free-running, on the outset, it is not clear if, and to what extent, their untamed execution affects the results in simulated scenarios. Here, we provide the first quantitative basis for establishing the need for generalized virtual time scheduling of VMs in network simulators,more » based on an actual prototyped implementations. To exercise breadth, our system is tested with multiple disparate applications: (a) a set of message passing parallel programs, (b) a computer worm propagation phenomenon, and (c) a mobile ad-hoc wireless network simulation. We define and use error metrics and benchmarks in scaled tests to empirically report the poor match of traditional, fairness-based VM scheduling to VM-based network simulation, and also clearly show the better performance of our simulation-specific scheduler, with up to 64 VMs hosted on a 12-core simulator node.« less

Applications and challenges of digital pathology and whole slide imaging.

PubMed

Higgins, C

2015-07-01

Virtual microscopy is a method for digitizing images of tissue on glass slides and using a computer to view, navigate, change magnification, focus and mark areas of interest. Virtual microscope systems (also called digital pathology or whole slide imaging systems) offer several advantages for biological scientists who use slides as part of their general, pharmaceutical, biotechnology or clinical research. The systems usually are based on one of two methodologies: area scanning or line scanning. Virtual microscope systems enable automatic sample detection, virtual-Z acquisition and creation of focal maps. Virtual slides are layered with multiple resolutions at each location, including the highest resolution needed to allow more detailed review of specific regions of interest. Scans may be acquired at 2, 10, 20, 40, 60 and 100 × or a combination of magnifications to highlight important detail. Digital microscopy starts when a slide collection is put into an automated or manual scanning system. The original slides are archived, then a server allows users to review multilayer digital images of the captured slides either by a closed network or by the internet. One challenge for adopting the technology is the lack of a universally accepted file format for virtual slides. Additional challenges include maintaining focus in an uneven sample, detecting specimens accurately, maximizing color fidelity with optimal brightness and contrast, optimizing resolution and keeping the images artifact-free. There are several manufacturers in the field and each has not only its own approach to these issues, but also its own image analysis software, which provides many options for users to enhance the speed, quality and accuracy of their process through virtual microscopy. Virtual microscope systems are widely used and are trusted to provide high quality solutions for teleconsultation, education, quality control, archiving, veterinary medicine, research and other fields.

The development of a virtual reality training curriculum for colonoscopy.

PubMed

Sugden, Colin; Aggarwal, Rajesh; Banerjee, Amrita; Haycock, Adam; Thomas-Gibson, Siwan; Williams, Christopher B; Darzi, Ara

2012-07-01

The development of a structured virtual reality (VR) training curriculum for colonoscopy using high-fidelity simulation. Colonoscopy requires detailed knowledge and technical skill. Changes to working practices in recent times have reduced the availability of traditional training opportunities. Much might, therefore, be achieved by applying novel technologies such as VR simulation to colonoscopy. Scientifically developed device-specific curricula aim to maximize the yield of laboratory-based training by focusing on validated modules and linking progression to the attainment of benchmarked proficiency criteria. Fifty participants comprised of 30 novices (<10 colonoscopies), 10 intermediates (100 to 500 colonoscopies), and 10 experienced (>500 colonoscopies) colonoscopists were recruited to participate. Surrogates of proficiency, such as number of procedures undertaken, determined prospective allocation to 1 of 3 groups (novice, intermediate, and experienced). Construct validity and learning value (comparison between groups and within groups respectively) for each task and metric on the chosen simulator model determined suitability for inclusion in the curriculum. Eight tasks in possession of construct validity and significant learning curves were included in the curriculum: 3 abstract tasks, 4 part-procedural tasks, and 1 procedural task. The whole-procedure task was valid for 11 metrics including the following: "time taken to complete the task" (1238, 343, and 293 s; P < 0.001) and "insertion length with embedded tip" (23.8, 3.6, and 4.9 cm; P = 0.005). Learning curves consistently plateaued at or beyond the ninth attempt. Valid metrics were used to define benchmarks, derived from the performance of the experienced cohort, for each included task. A comprehensive, stratified, benchmarked, whole-procedure curriculum has been developed for a modern high-fidelity VR colonoscopy simulator.

First-Order Model Management With Variable-Fidelity Physics Applied to Multi-Element Airfoil Optimization

NASA Technical Reports Server (NTRS)

Alexandrov, N. M.; Nielsen, E. J.; Lewis, R. M.; Anderson, W. K.

2000-01-01

First-order approximation and model management is a methodology for a systematic use of variable-fidelity models or approximations in optimization. The intent of model management is to attain convergence to high-fidelity solutions with minimal expense in high-fidelity computations. The savings in terms of computationally intensive evaluations depends on the ability of the available lower-fidelity model or a suite of models to predict the improvement trends for the high-fidelity problem, Variable-fidelity models can be represented by data-fitting approximations, variable-resolution models. variable-convergence models. or variable physical fidelity models. The present work considers the use of variable-fidelity physics models. We demonstrate the performance of model management on an aerodynamic optimization of a multi-element airfoil designed to operate in the transonic regime. Reynolds-averaged Navier-Stokes equations represent the high-fidelity model, while the Euler equations represent the low-fidelity model. An unstructured mesh-based analysis code FUN2D evaluates functions and sensitivity derivatives for both models. Model management for the present demonstration problem yields fivefold savings in terms of high-fidelity evaluations compared to optimization done with high-fidelity computations alone.

Virtual Reality Simulation of the International Space Welding Experiment

NASA Technical Reports Server (NTRS)

Phillips, James A.

1996-01-01

Virtual Reality (VR) is a set of breakthrough technologies that allow a human being to enter and fully experience a 3-dimensional, computer simulated environment. A true virtual reality experience meets three criteria: (1) It involves 3-dimensional computer graphics; (2) It includes real-time feedback and response to user actions; and (3) It must provide a sense of immersion. Good examples of a virtual reality simulator are the flight simulators used by all branches of the military to train pilots for combat in high performance jet fighters. The fidelity of such simulators is extremely high -- but so is the price tag, typically millions of dollars. Virtual reality teaching and training methods are manifestly effective, and we have therefore implemented a VR trainer for the International Space Welding Experiment. My role in the development of the ISWE trainer consisted of the following: (1) created texture-mapped models of the ISWE's rotating sample drum, technology block, tool stowage assembly, sliding foot restraint, and control panel; (2) developed C code for control panel button selection and rotation of the sample drum; (3) In collaboration with Tim Clark (Antares Virtual Reality Systems), developed a serial interface box for the PC and the SGI Indigo so that external control devices, similar to ones actually used on the ISWE, could be used to control virtual objects in the ISWE simulation; (4) In collaboration with Peter Wang (SFFP) and Mark Blasingame (Boeing), established the interference characteristics of the VIM 1000 head-mounted-display and tested software filters to correct the problem; (5) In collaboration with Peter Wang and Mark Blasingame, established software and procedures for interfacing the VPL DataGlove and the Polhemus 6DOF position sensors to the SGI Indigo serial ports. The majority of the ISWE modeling effort was conducted on a PC-based VR Workstation, described below.

The Development and Deployment of a Virtual Unit Operations Laboratory

ERIC Educational Resources Information Center

Vaidyanath, Sreeram; Williams, Jason; Hilliard, Marcus; Wiesner, Theodore

2007-01-01

Computer-simulated experiments offer many benefits to engineering curricula in the areas of safety, cost, and flexibility. We report our experience in developing and deploying a computer-simulated unit operations laboratory, driven by the guiding principle of maximum fidelity to the physical lab. We find that, while the up-front investment in…

A comparison of the upper limb movement kinematics utilized by children playing virtual and real table tennis.

PubMed

Bufton, Amy; Campbell, Amity; Howie, Erin; Straker, Leon

2014-12-01

Active virtual games (AVG) may facilitate gross motor skill development, depending on their fidelity. This study compared the movement patterns of nineteen 10-12 yr old children, while playing table tennis on three AVG consoles (Nintendo Wii, Xbox Kinect, Sony Move) and as a real world task. Wrist and elbow joint angles and hand path distance and speed were captured. Children playing real table tennis had significantly smaller (e.g. Wrist Angle Forehand Real-Kinect: Mean Difference (MD): -18.2°, 95% Confidence Interval (CI): -26.15 to -10.26) and slower (e.g. Average Speed Forehand Real-Kinect: MD: -1.98 ms(-1), 95% CI: -2.35 to -1.61) movements than when using all three AVGs. Hand path distance was smaller in forehand and backhand strokes (e.g. Kinect-Wii: MD: 0.46 m, 95% CI: 0.13-0.79) during playing with Kinect than Move and Wii. The movement patterns when playing real and virtual table tennis were different and this may impede the development of real world gross motor skills. Several elements, including display, input and task characteristics, may have contributed to the differences in movement patterns observed. Understanding the interface components for AVGs may help development of higher fidelity games to potentially enhance the development of gross motor skill and thus participation in PA. Copyright © 2014 Elsevier B.V. All rights reserved.

Surgical simulation: a urological perspective.

PubMed

Wignall, Geoffrey R; Denstedt, John D; Preminger, Glenn M; Cadeddu, Jeffrey A; Pearle, Margaret S; Sweet, Robert M; McDougall, Elspeth M

2008-05-01

Surgical education is changing rapidly as several factors including budget constraints and medicolegal concerns limit opportunities for urological trainees. New methods of skills training such as low fidelity bench trainers and virtual reality simulators offer new avenues for surgical education. In addition, surgical simulation has the potential to allow practicing surgeons to develop new skills and maintain those they already possess. We provide a review of the background, current status and future directions of surgical simulators as they pertain to urology. We performed a literature review and an overview of surgical simulation in urology. Surgical simulators are in various stages of development and validation. Several simulators have undergone extensive validation studies and are in use in surgical curricula. While virtual reality simulators offer the potential to more closely mimic reality and present entire operations, low fidelity simulators remain useful in skills training, particularly for novices and junior trainees. Surgical simulation remains in its infancy. However, the potential to shorten learning curves for difficult techniques and practice surgery without risk to patients continues to drive the development of increasingly more advanced and realistic models. Surgical simulation is an exciting area of surgical education. The future is bright as advancements in computing and graphical capabilities offer new innovations in simulator technology. Simulators must continue to undergo rigorous validation studies to ensure that time spent by trainees on bench trainers and virtual reality simulators will translate into improved surgical skills in the operating room.

The (human) science of medical virtual learning environments.

PubMed

Stone, Robert J

2011-01-27

The uptake of virtual simulation technologies in both military and civilian surgical contexts has been both slow and patchy. The failure of the virtual reality community in the 1990s and early 2000s to deliver affordable and accessible training systems stems not only from an obsessive quest to develop the 'ultimate' in so-called 'immersive' hardware solutions, from head-mounted displays to large-scale projection theatres, but also from a comprehensive lack of attention to the needs of the end users. While many still perceive the science of simulation to be defined by technological advances, such as computing power, specialized graphics hardware, advanced interactive controllers, displays and so on, the true science underpinning simulation--the science that helps to guarantee the transfer of skills from the simulated to the real--is that of human factors, a well-established discipline that focuses on the abilities and limitations of the end user when designing interactive systems, as opposed to the more commercially explicit components of technology. Based on three surgical simulation case studies, the importance of a human factors approach to the design of appropriate simulation content and interactive hardware for medical simulation is illustrated. The studies demonstrate that it is unnecessary to pursue real-world fidelity in all instances in order to achieve psychological fidelity--the degree to which the simulated tasks reproduce and foster knowledge, skills and behaviours that can be reliably transferred to real-world training applications.

Virtual versus face-to-face clinical simulation in relation to student knowledge, anxiety, and self-confidence in maternal-newborn nursing: A randomized controlled trial.

PubMed

Cobbett, Shelley; Snelgrove-Clarke, Erna

2016-10-01

Clinical simulations can provide students with realistic clinical learning environments to increase their knowledge, self-confidence, and decrease their anxiety prior to entering clinical practice settings. To compare the effectiveness of two maternal newborn clinical simulation scenarios; virtual clinical simulation and face-to-face high fidelity manikin simulation. Randomized pretest-posttest design. A public research university in Canada. Fifty-six third year Bachelor of Science in Nursing students. Participants were randomized to either face-to-face or virtual clinical simulation and then to dyads for completion of two clinical simulations. Measures included: (1) Nursing Anxiety and Self-Confidence with Clinical Decision Making Scale (NASC-CDM) (White, 2011), (2) knowledge pretest and post-test related to preeclampsia and group B strep, and (3) Simulation Completion Questionnaire. Before and after each simulation students completed a knowledge test and the NASC-CDM and the Simulation Completion Questionnaire at study completion. There were no statistically significant differences in student knowledge and self-confidence between face-to-face and virtual clinical simulations. Anxiety scores were higher for students in the virtual clinical simulation than for those in the face-to-face simulation. Students' self-reported preference was face-to-face citing the similarities to practicing in a 'real' situation and the immediate debrief. Students not liking the virtual clinical simulation most often cited technological issues as their rationale. Given the equivalency of knowledge and self-confidence when undergraduate nursing students participate in either maternal newborn clinical scenarios of face-to-face or virtual clinical simulation identified in this trial, it is important to take into the consideration costs and benefits/risks of simulation implementation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Image-guided laser projection for port placement in minimally invasive surgery.

PubMed

Marmurek, Jonathan; Wedlake, Chris; Pardasani, Utsav; Eagleson, Roy; Peters, Terry

2006-01-01

We present an application of an augmented reality laser projection system in which procedure-specific optimal incision sites, computed from pre-operative image acquisition, are superimposed on a patient to guide port placement in minimally invasive surgery. Tests were conducted to evaluate the fidelity of computed and measured port configurations, and to validate the accuracy with which a surgical tool-tip can be placed at an identified virtual target. A high resolution volumetric image of a thorax phantom was acquired using helical computed tomography imaging. Oriented within the thorax, a phantom organ with marked targets was visualized in a virtual environment. A graphical interface enabled marking the locations of target anatomy, and calculation of a grid of potential port locations along the intercostal rib lines. Optimal configurations of port positions and tool orientations were determined by an objective measure reflecting image-based indices of surgical dexterity, hand-eye alignment, and collision detection. Intra-operative registration of the computed virtual model and the phantom anatomy was performed using an optical tracking system. Initial trials demonstrated that computed and projected port placement provided direct access to target anatomy with an accuracy of 2 mm.

Integrating 4-d light-sheet imaging with interactive virtual reality to recapitulate developmental cardiac mechanics and physiology

NASA Astrophysics Data System (ADS)

Ding, Yichen; Yu, Jing; Abiri, Arash; Abiri, Parinaz; Lee, Juhyun; Chang, Chih-Chiang; Baek, Kyung In; Sevag Packard, René R.; Hsiai, Tzung K.

2018-02-01

There currently is a limited ability to interactively study developmental cardiac mechanics and physiology. We therefore combined light-sheet fluorescence microscopy (LSFM) with virtual reality (VR) to provide a hybrid platform for 3- dimensional (3-D) architecture and time-dependent cardiac contractile function characterization. By taking advantage of the rapid acquisition, high axial resolution, low phototoxicity, and high fidelity in 3-D and 4-D (3-D spatial + 1-D time or spectra), this VR-LSFM hybrid methodology enables interactive visualization and quantification otherwise not available by conventional methods such as routine optical microscopes. We hereby demonstrate multi-scale applicability of VR-LSFM to 1) interrogate skin fibroblasts interacting with a hyaluronic acid-based hydrogel, 2) navigate through the endocardial trabecular network during zebrafish development, and 3) localize gene therapy-mediated potassium channel expression in adult murine hearts. We further combined our batch intensity normalized segmentation (BINS) algorithm with deformable image registration (DIR) to interface a VR environment for the analysis of cardiac contraction. Thus, the VR-LSFM hybrid platform demonstrates an efficient and robust framework for creating a user-directed microenvironment in which we uncovered developmental cardiac mechanics and physiology with high spatiotemporal resolution.

Integrating light-sheet imaging with virtual reality to recapitulate developmental cardiac mechanics.

PubMed

Ding, Yichen; Abiri, Arash; Abiri, Parinaz; Li, Shuoran; Chang, Chih-Chiang; Baek, Kyung In; Hsu, Jeffrey J; Sideris, Elias; Li, Yilei; Lee, Juhyun; Segura, Tatiana; Nguyen, Thao P; Bui, Alexander; Sevag Packard, René R; Fei, Peng; Hsiai, Tzung K

2017-11-16

Currently, there is a limited ability to interactively study developmental cardiac mechanics and physiology. We therefore combined light-sheet fluorescence microscopy (LSFM) with virtual reality (VR) to provide a hybrid platform for 3D architecture and time-dependent cardiac contractile function characterization. By taking advantage of the rapid acquisition, high axial resolution, low phototoxicity, and high fidelity in 3D and 4D (3D spatial + 1D time or spectra), this VR-LSFM hybrid methodology enables interactive visualization and quantification otherwise not available by conventional methods, such as routine optical microscopes. We hereby demonstrate multiscale applicability of VR-LSFM to (a) interrogate skin fibroblasts interacting with a hyaluronic acid-based hydrogel, (b) navigate through the endocardial trabecular network during zebrafish development, and (c) localize gene therapy-mediated potassium channel expression in adult murine hearts. We further combined our batch intensity normalized segmentation algorithm with deformable image registration to interface a VR environment with imaging computation for the analysis of cardiac contraction. Thus, the VR-LSFM hybrid platform demonstrates an efficient and robust framework for creating a user-directed microenvironment in which we uncovered developmental cardiac mechanics and physiology with high spatiotemporal resolution.

Integrating light-sheet imaging with virtual reality to recapitulate developmental cardiac mechanics

PubMed Central

Ding, Yichen; Abiri, Arash; Abiri, Parinaz; Li, Shuoran; Chang, Chih-Chiang; Hsu, Jeffrey J.; Sideris, Elias; Li, Yilei; Lee, Juhyun; Segura, Tatiana; Nguyen, Thao P.; Bui, Alexander; Sevag Packard, René R.; Hsiai, Tzung K.

2017-01-01

Currently, there is a limited ability to interactively study developmental cardiac mechanics and physiology. We therefore combined light-sheet fluorescence microscopy (LSFM) with virtual reality (VR) to provide a hybrid platform for 3D architecture and time-dependent cardiac contractile function characterization. By taking advantage of the rapid acquisition, high axial resolution, low phototoxicity, and high fidelity in 3D and 4D (3D spatial + 1D time or spectra), this VR-LSFM hybrid methodology enables interactive visualization and quantification otherwise not available by conventional methods, such as routine optical microscopes. We hereby demonstrate multiscale applicability of VR-LSFM to (a) interrogate skin fibroblasts interacting with a hyaluronic acid–based hydrogel, (b) navigate through the endocardial trabecular network during zebrafish development, and (c) localize gene therapy-mediated potassium channel expression in adult murine hearts. We further combined our batch intensity normalized segmentation algorithm with deformable image registration to interface a VR environment with imaging computation for the analysis of cardiac contraction. Thus, the VR-LSFM hybrid platform demonstrates an efficient and robust framework for creating a user-directed microenvironment in which we uncovered developmental cardiac mechanics and physiology with high spatiotemporal resolution. PMID:29202458

Learning nursing procedures: the influence of simulator fidelity and student gender on teaching effectiveness.

PubMed

Grady, Janet L; Kehrer, Rosemary G; Trusty, Carole E; Entin, Eileen B; Entin, Elliot E; Brunye, Tad T

2008-09-01

Simulation technologies are gaining widespread acceptance across a variety of educational domains and applications. The current research examines whether basic nursing procedure training with high-fidelity versus low-fidelity mannequins results in differential skill acquisition and perceptions of simulator utility. Fifty-two first-year students were taught nasogastric tube and indwelling urinary catheter insertion in one of two ways. The first group learned nasogastric tube and urinary catheter insertion using high-fidelity and low-fidelity mannequins, respectively, and the second group learned nasogastric tube and urinary catheter insertion using low-fidelity and high-fidelity mannequins, respectively. The dependent measures included student performance on nasogastric tube and urinary catheter insertion testing, as measured by observer-based instruments, and self-report questionnaires probing student attitudes about the use of simulation in nursing education. Results demonstrated higher performance with high-fidelity than with low-fidelity mannequin training. In response to a self-report posttraining questionnaire, participants expressed a more positive attitude toward the high-fidelity mannequin, especially regarding its responsiveness and realism.

Colonoscopy procedure simulation: virtual reality training based on a real time computational approach.

PubMed

Wen, Tingxi; Medveczky, David; Wu, Jackie; Wu, Jianhuang

2018-01-25

Colonoscopy plays an important role in the clinical screening and management of colorectal cancer. The traditional 'see one, do one, teach one' training style for such invasive procedure is resource intensive and ineffective. Given that colonoscopy is difficult, and time-consuming to master, the use of virtual reality simulators to train gastroenterologists in colonoscopy operations offers a promising alternative. In this paper, a realistic and real-time interactive simulator for training colonoscopy procedure is presented, which can even include polypectomy simulation. Our approach models the colonoscopy as thick flexible elastic rods with different resolutions which are dynamically adaptive to the curvature of the colon. More material characteristics of this deformable material are integrated into our discrete model to realistically simulate the behavior of the colonoscope. We present a simulator for training colonoscopy procedure. In addition, we propose a set of key aspects of our simulator that give fast, high fidelity feedback to trainees. We also conducted an initial validation of this colonoscopic simulator to determine its clinical utility and efficacy.

Evaluation of haptic interfaces for simulation of drill vibration in virtual temporal bone surgery.

PubMed

Ghasemloonia, Ahmad; Baxandall, Shalese; Zareinia, Kourosh; Lui, Justin T; Dort, Joseph C; Sutherland, Garnette R; Chan, Sonny

2016-11-01

Surgical training is evolving from an observership model towards a new paradigm that includes virtual-reality (VR) simulation. In otolaryngology, temporal bone dissection has become intimately linked with VR simulation as the complexity of anatomy demands a high level of surgeon aptitude and confidence. While an adequate 3D visualization of the surgical site is available in current simulators, the force feedback rendered during haptic interaction does not convey vibrations. This lack of vibration rendering limits the simulation fidelity of a surgical drill such as that used in temporal bone dissection. In order to develop an immersive simulation platform capable of haptic force and vibration feedback, the efficacy of hand controllers for rendering vibration in different drilling circumstances needs to be investigated. In this study, the vibration rendering ability of four different haptic hand controllers were analyzed and compared to find the best commercial haptic hand controller. A test-rig was developed to record vibrations encountered during temporal bone dissection and a software was written to render the recorded signals without adding hardware to the system. An accelerometer mounted on the end-effector of each device recorded the rendered vibration signals. The newly recorded vibration signal was compared with the input signal in both time and frequency domains by coherence and cross correlation analyses to quantitatively measure the fidelity of these devices in terms of rendering vibrotactile drilling feedback in different drilling conditions. This method can be used to assess the vibration rendering ability in VR simulation systems and selection of ideal haptic devices. Copyright © 2016 Elsevier Ltd. All rights reserved.

Distributed virtual environment for emergency medical training

NASA Astrophysics Data System (ADS)

Stytz, Martin R.; Banks, Sheila B.; Garcia, Brian W.; Godsell-Stytz, Gayl M.

1997-07-01

In many professions where individuals must work in a team in a high stress environment to accomplish a time-critical task, individual and team performance can benefit from joint training using distributed virtual environments (DVEs). One professional field that lacks but needs a high-fidelity team training environment is the field of emergency medicine. Currently, emergency department (ED) medical personnel train by using words to create a metal picture of a situation for the physician and staff, who then cooperate to solve the problems portrayed by the word picture. The need in emergency medicine for realistic virtual team training is critical because ED staff typically encounter rarely occurring but life threatening situations only once in their careers and because ED teams currently have no realistic environment in which to practice their team skills. The resulting lack of experience and teamwork makes diagnosis and treatment more difficult. Virtual environment based training has the potential to redress these shortfalls. The objective of our research is to develop a state-of-the-art virtual environment for emergency medicine team training. The virtual emergency room (VER) allows ED physicians and medical staff to realistically prepare for emergency medical situations by performing triage, diagnosis, and treatment on virtual patients within an environment that provides them with the tools they require and the team environment they need to realistically perform these three tasks. There are several issues that must be addressed before this vision is realized. The key issues deal with distribution of computations; the doctor and staff interface to the virtual patient and ED equipment; the accurate simulation of individual patient organs' response to injury, medication, and treatment; and an accurate modeling of the symptoms and appearance of the patient while maintaining a real-time interaction capability. Our ongoing work addresses all of these issues. In this paper we report on our prototype VER system and its distributed system architecture for an emergency department distributed virtual environment for emergency medical staff training. The virtual environment enables emergency department physicians and staff to develop their diagnostic and treatment skills using the virtual tools they need to perform diagnostic and treatment tasks. Virtual human imagery, and real-time virtual human response are used to create the virtual patient and present a scenario. Patient vital signs are available to the emergency department team as they manage the virtual case. The work reported here consists of the system architectures we developed for the distributed components of the virtual emergency room. The architectures we describe consist of the network level architecture as well as the software architecture for each actor within the virtual emergency room. We describe the role of distributed interactive simulation and other enabling technologies within the virtual emergency room project.

The effect of bench model fidelity on fluoroscopy-guided transforaminal epidural injection training: a randomized control study.

PubMed

Gonzalez-Cota, Alan; Chiravuri, Srinivas; Stansfield, R Brent; Brummett, Chad M; Hamstra, Stanley J

2013-01-01

The purpose of this study was to determine whether high-fidelity simulators provide greater benefit than low-fidelity models in training fluoroscopy-guided transforaminal epidural injection. This educational study was a single-center, prospective, randomized 3-arm pretest-posttest design with a control arm. Eighteen anesthesia and physical medicine and rehabilitation residents were instructed how to perform a fluoroscopy-guided transforaminal epidural injection and assessed by experts on a reusable injectable phantom cadaver. The high- and low-fidelity groups received 30 minutes of supervised hands-on practice according to group assignment, and the control group received 30 minutes of didactic instruction from an expert. We found no differences at posttest between the high- and low-fidelity groups on global ratings of performance (P = 0.17) or checklist scores (P = 0.81). Participants who received either form of hands-on training significantly outperformed the control group on both the global rating of performance (control vs low-fidelity, P = 0.0048; control vs high-fidelity, P = 0.0047) and the checklist (control vs low-fidelity, P = 0.0047; control vs high-fidelity, P = 0.0047). Training an epidural procedure using a low-fidelity model may be equally effective as training on a high-fidelity model. These results are consistent with previous research on a variety of interventional procedures and further demonstrate the potential impact of simple, low-fidelity training models.

Needs analysis for developing a virtual-reality NOTES simulator.

PubMed

Sankaranarayanan, Ganesh; Matthes, Kai; Nemani, Arun; Ahn, Woojin; Kato, Masayuki; Jones, Daniel B; Schwaitzberg, Steven; De, Suvranu

2013-05-01

INTRODUCTION AND STUDY AIM: Natural orifice translumenal endoscopic surgery (NOTES) is an emerging surgical technique that requires a cautious adoption approach to ensure patient safety. High-fidelity virtual-reality-based simulators allow development of new surgical procedures and tools and train medical personnel without risk to human patients. As part of a project funded by the National Institutes of Health, we are developing the virtual transluminal endoscopic surgery trainer (VTEST) for this purpose. The objective of this study is to conduct a structured needs analysis to identify the design parameters for such a virtual-reality-based simulator for NOTES. A 30-point questionnaire was distributed at the 2011 National Orifice Surgery Consortium for Assessment and Research meeting to obtain responses from experts. Ordinal logistic regression and the Wilcoxon rank-sum test were used for analysis. A total of 22 NOTES experts participated in the study. Cholecystectomy (CE, 68 %) followed by appendectomy (AE, 63 %) (CE vs AE, p = 0.0521) was selected as the first choice for simulation. Flexible (FL, 47 %) and hybrid (HY, 47 %) approaches were equally favorable compared with rigid (RI, 6 %) with p < 0.001 for both FL versus RI and HY versus RI. The transvaginal approach was preferred 3 to 1 to the transgastric. Most participants preferred two-channel (2C) scopes (65 %) compared with single (1C) or three (3C) or more channels with p < 0.001 for both 2C versus 1C and 2C versus 3C. The importance of force feedback and the utility of a virtual NOTES simulator in training and testing new tools for NOTES were rated very high by the participants. Our study reinforces the importance of developing a virtual NOTES simulator and clearly presents expert preferences. The results of this analysis will direct our initial development of the VTEST platform.

Complete tomography of a high-fidelity solid-state entangled spin-photon qubit pair.

PubMed

De Greve, Kristiaan; McMahon, Peter L; Yu, Leo; Pelc, Jason S; Jones, Cody; Natarajan, Chandra M; Kim, Na Young; Abe, Eisuke; Maier, Sebastian; Schneider, Christian; Kamp, Martin; Höfling, Sven; Hadfield, Robert H; Forchel, Alfred; Fejer, M M; Yamamoto, Yoshihisa

2013-01-01

Entanglement between stationary quantum memories and photonic qubits is crucial for future quantum communication networks. Although high-fidelity spin-photon entanglement was demonstrated in well-isolated atomic and ionic systems, in the solid-state, where massively parallel, scalable networks are most realistically conceivable, entanglement fidelities are typically limited due to intrinsic environmental interactions. Distilling high-fidelity entangled pairs from lower-fidelity precursors can act as a remedy, but the required overhead scales unfavourably with the initial entanglement fidelity. With spin-photon entanglement as a crucial building block for entangling quantum network nodes, obtaining high-fidelity entangled pairs becomes imperative for practical realization of such networks. Here we report the first results of complete state tomography of a solid-state spin-photon-polarization-entangled qubit pair, using a single electron-charged indium arsenide quantum dot. We demonstrate record-high fidelity in the solid-state of well over 90%, and the first (99.9%-confidence) achievement of a fidelity that will unambiguously allow for entanglement distribution in solid-state quantum repeater networks.

Gaussian functional regression for output prediction: Model assimilation and experimental design

NASA Astrophysics Data System (ADS)

Nguyen, N. C.; Peraire, J.

2016-03-01

In this paper, we introduce a Gaussian functional regression (GFR) technique that integrates multi-fidelity models with model reduction to efficiently predict the input-output relationship of a high-fidelity model. The GFR method combines the high-fidelity model with a low-fidelity model to provide an estimate of the output of the high-fidelity model in the form of a posterior distribution that can characterize uncertainty in the prediction. A reduced basis approximation is constructed upon the low-fidelity model and incorporated into the GFR method to yield an inexpensive posterior distribution of the output estimate. As this posterior distribution depends crucially on a set of training inputs at which the high-fidelity models are simulated, we develop a greedy sampling algorithm to select the training inputs. Our approach results in an output prediction model that inherits the fidelity of the high-fidelity model and has the computational complexity of the reduced basis approximation. Numerical results are presented to demonstrate the proposed approach.

Nonlinear information fusion algorithms for data-efficient multi-fidelity modelling.

PubMed

Perdikaris, P; Raissi, M; Damianou, A; Lawrence, N D; Karniadakis, G E

2017-02-01

Multi-fidelity modelling enables accurate inference of quantities of interest by synergistically combining realizations of low-cost/low-fidelity models with a small set of high-fidelity observations. This is particularly effective when the low- and high-fidelity models exhibit strong correlations, and can lead to significant computational gains over approaches that solely rely on high-fidelity models. However, in many cases of practical interest, low-fidelity models can only be well correlated to their high-fidelity counterparts for a specific range of input parameters, and potentially return wrong trends and erroneous predictions if probed outside of their validity regime. Here we put forth a probabilistic framework based on Gaussian process regression and nonlinear autoregressive schemes that is capable of learning complex nonlinear and space-dependent cross-correlations between models of variable fidelity, and can effectively safeguard against low-fidelity models that provide wrong trends. This introduces a new class of multi-fidelity information fusion algorithms that provide a fundamental extension to the existing linear autoregressive methodologies, while still maintaining the same algorithmic complexity and overall computational cost. The performance of the proposed methods is tested in several benchmark problems involving both synthetic and real multi-fidelity datasets from computational fluid dynamics simulations.

Vids: Version 2.0 Alpha Visualization Engine

DTIC Science & Technology

2018-04-25

fidelity than existing efforts. Vids is a project aimed at producing more dynamic and interactive visualization tools using modern computer game ...move through and interact with the data to improve informational understanding. The Vids software leverages off-the-shelf modern game development...analysis and correlations. Recently, an ARL-pioneered project named Virtual Reality Data Analysis Environment (VRDAE) used VR and a modern game engine

Efficacy of Individualized Clinical Coaching in a Virtual Reality Classroom for Increasing Teachers' Fidelity of Implementation of Discrete Trial Teaching

ERIC Educational Resources Information Center

Garland, Krista Vince; Vasquez, Eleazar, III; Pearl, Cynthia

2012-01-01

Discrete-trials teaching (DTT) is an evidence-based practice used in educational programs for children with autism spectrum disorders (ASD). Although there is strong demand for preparing teachers to effectively implement DTT, there is a scarcity of published research on such studies. A multiple baseline across participants design was utilized to…

High-fidelity Modeling of Local Effects of Damage for Derated Offshore Wind Turbines

NASA Astrophysics Data System (ADS)

Richards, Phillip W.; Griffith, D. Todd; Hodges, Dewey H.

2014-06-01

Offshore wind power production is an attractive clean energy option, but the difficulty of access can lead to expensive and rare opportunities for maintenance. As part of the Structural Health and Prognostics Management (SHPM) project at Sandia National Laboratories, smart loads management (controls) are investigated for their potential to increase the fatigue life of offshore wind turbine rotor blades. Derating refers to altering the rotor angular speed and blade pitch to limit power production and loads on the rotor blades. High- fidelity analysis techniques like 3D finite element modeling (FEM) should be used alongside beam models of wind turbine blades to characterize these control strategies in terms of their effect to mitigate fatigue damage and extend life of turbine blades. This study will consider a commonly encountered damage type for wind turbine blades, the trailing edge disbond, and show how FEM can be used to quantify the effect of operations and control strategies designed to extend the fatigue life of damaged blades. The Virtual Crack Closure Technique (VCCT) will be used to post-process the displacement and stress results to provide estimates of damage severity/criticality and provide a means to estimate the fatigue life under a given operations and control strategy.

Multi-fidelity stochastic collocation method for computation of statistical moments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Xueyu, E-mail: xueyu-zhu@uiowa.edu; Linebarger, Erin M., E-mail: aerinline@sci.utah.edu; Xiu, Dongbin, E-mail: xiu.16@osu.edu

We present an efficient numerical algorithm to approximate the statistical moments of stochastic problems, in the presence of models with different fidelities. The method extends the multi-fidelity approximation method developed in . By combining the efficiency of low-fidelity models and the accuracy of high-fidelity models, our method exhibits fast convergence with a limited number of high-fidelity simulations. We establish an error bound of the method and present several numerical examples to demonstrate the efficiency and applicability of the multi-fidelity algorithm.

High Versus Low Theoretical Fidelity Pedometer Intervention Using Social-Cognitive Theory on Steps and Self-Efficacy.

PubMed

Raedeke, Thomas D; Dlugonski, Deirdre

2017-12-01

This study was designed to compare a low versus high theoretical fidelity pedometer intervention applying social-cognitive theory on step counts and self-efficacy. Fifty-six public university employees participated in a 10-week randomized controlled trial with 2 conditions that varied in theoretical fidelity. Participants in the high theoretical fidelity condition wore a pedometer and participated in a weekly group walk followed by a meeting to discuss cognitive-behavioral strategies targeting self-efficacy. Participants in the low theoretical fidelity condition met for a group walk and also used a pedometer as a motivational tool and to monitor steps. Step counts were assessed throughout the 10-week intervention and after a no-treatment follow-up (20 weeks and 30 weeks). Self-efficacy was measured preintervention and postintervention. Participants in the high theoretical fidelity condition increased daily steps by 2,283 from preintervention to postintervention, whereas participants in the low fidelity condition demonstrated minimal change during the same time period (p = .002). Individuals attending at least 80% of the sessions in the high theoretical fidelity condition showed an increase of 3,217 daily steps (d = 1.03), whereas low attenders increased by 925 (d = 0.40). Attendance had minimal impact in the low theoretical fidelity condition. Follow-up data revealed that step counts were at least somewhat maintained. For self-efficacy, participants in the high, compared with those in the low, theoretical fidelity condition showed greater improvements. Findings highlight the importance of basing activity promotion efforts on theory. The high theoretical fidelity intervention that included cognitive-behavioral strategies targeting self-efficacy was more effective than the low theoretical fidelity intervention, especially for those with high attendance.

A Facile Two-Step Method to Implement N√ {iSWAP} and N√ {SWAP} Gates in a Circuit QED

NASA Astrophysics Data System (ADS)

Said, T.; Chouikh, A.; Bennai, M.

2018-05-01

We propose a way for implementing a two-step N√ {iSWAP} and N √ {SWAP} gates based on the qubit-qubit interaction with N superconducting qubits, by coupling them to a resonator driven by a strong microwave field. The operation times do not increase with the growth of the qubit number. Due to the virtual excitations of the resonator, the scheme is insensitive to the decay of the resonator. Numerical analysis shows that the scheme can be implemented with high fidelity. Moreover, we propose a detailed procedure and analyze the experimental feasibility. So, our proposal can be experimentally realized in the range of current circuit QED techniques.

NYU3T: teaching, technology, teamwork: a model for interprofessional education scalability and sustainability.

PubMed

Djukic, Maja; Fulmer, Terry; Adams, Jennifer G; Lee, Sabrina; Triola, Marc M

2012-09-01

Interprofessional education is a critical precursor to effective teamwork and the collaboration of health care professionals in clinical settings. Numerous barriers have been identified that preclude scalable and sustainable interprofessional education (IPE) efforts. This article describes NYU3T: Teaching, Technology, Teamwork, a model that uses novel technologies such as Web-based learning, virtual patients, and high-fidelity simulation to overcome some of the common barriers and drive implementation of evidence-based teamwork curricula. It outlines the program's curricular components, implementation strategy, evaluation methods, and lessons learned from the first year of delivery and describes implications for future large-scale IPE initiatives. Copyright © 2012 Elsevier Inc. All rights reserved.

An information theoretic approach to use high-fidelity codes to calibrate low-fidelity codes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lewis, Allison, E-mail: lewis.allison10@gmail.com; Smith, Ralph; Williams, Brian

For many simulation models, it can be prohibitively expensive or physically infeasible to obtain a complete set of experimental data to calibrate model parameters. In such cases, one can alternatively employ validated higher-fidelity codes to generate simulated data, which can be used to calibrate the lower-fidelity code. In this paper, we employ an information-theoretic framework to determine the reduction in parameter uncertainty that is obtained by evaluating the high-fidelity code at a specific set of design conditions. These conditions are chosen sequentially, based on the amount of information that they contribute to the low-fidelity model parameters. The goal is tomore » employ Bayesian experimental design techniques to minimize the number of high-fidelity code evaluations required to accurately calibrate the low-fidelity model. We illustrate the performance of this framework using heat and diffusion examples, a 1-D kinetic neutron diffusion equation, and a particle transport model, and include initial results from the integration of the high-fidelity thermal-hydraulics code Hydra-TH with a low-fidelity exponential model for the friction correlation factor.« less

Design Considerations of a Virtual Laboratory for Advanced X-ray Sources

NASA Astrophysics Data System (ADS)

Luginsland, J. W.; Frese, M. H.; Frese, S. D.; Watrous, J. J.; Heileman, G. L.

2004-11-01

The field of scientific computation has greatly advanced in the last few years, resulting in the ability to perform complex computer simulations that can predict the performance of real-world experiments in a number of fields of study. Among the forces driving this new computational capability is the advent of parallel algorithms, allowing calculations in three-dimensional space with realistic time scales. Electromagnetic radiation sources driven by high-voltage, high-current electron beams offer an area to further push the state-of-the-art in high fidelity, first-principles simulation tools. The physics of these x-ray sources combine kinetic plasma physics (electron beams) with dense fluid-like plasma physics (anode plasmas) and x-ray generation (bremsstrahlung). There are a number of mature techniques and software packages for dealing with the individual aspects of these sources, such as Particle-In-Cell (PIC), Magneto-Hydrodynamics (MHD), and radiation transport codes. The current effort is focused on developing an object-oriented software environment using the Rational© Unified Process and the Unified Modeling Language (UML) to provide a framework where multiple 3D parallel physics packages, such as a PIC code (ICEPIC), a MHD code (MACH), and a x-ray transport code (ITS) can co-exist in a system-of-systems approach to modeling advanced x-ray sources. Initial software design and assessments of the various physics algorithms' fidelity will be presented.

Spiritual and Affective Responses to a Physical Church and Corresponding Virtual Model.

PubMed

Murdoch, Matt; Davies, Jim

2017-11-01

Architectural and psychological theories posit that built environments have the potential to elicit complex psychological responses. However, few researchers have seriously explored this potential. Given the increasing importance and fidelity of virtual worlds, such research should explore whether virtual models of built environments are also capable of eliciting complex psychological responses. The goal of this study was to test these hypotheses, using a church, a corresponding virtual model, and an inclusive measure of state spirituality ("spiritual feelings"). Participants (n = 33) explored a physical church and corresponding virtual model, completing a measure of spiritual feelings after exploring the outside and inside of each version of the church. Using spiritual feelings after exploring the outside of the church as a baseline measure, change in state spirituality was assessed by taking the difference between spiritual feelings after exploring the inside and outside of the church (inside-outside) for both models. Although this change was greater in response to the physical church, there was no significant difference between the two models in eliciting such change in spiritual feelings. Despite the limitations of this exploratory study, these findings indicate that both built environments and corresponding virtual models are capable of evoking complex psychological responses.

How Fidelity invests in service professionals.

PubMed

McColgan, E A

1997-01-01

If you're in the business of service delivery, investment in the training and development of your staff is one of the keys to your company's success. But what's the best way to design and implement your investment? In 1994, Fidelity Institutional Retirement Services Company (FIRSCo) needed to ensure that its rapidly expanding staff maintained the company's high levels of customer satisfaction. The solution, according to Ellyn McColgan, formerly an executive vice president of FIRSCo and now the president of Fidelity Investments Tax-Exempt Services Company, was to reach out to its service associates with a powerful new model for training and development called Service Delivery University. SDU is a virtual university with a content-based core curriculum and five colleges that focus on business concepts and skills. It is driven by three principles. First, all training must be directly aligned with the company's strategic and financial objectives and focused on customer needs. Second, service delivery is a profession and should be taught as such. And finally, professional development should be the primary responsibility of line managers rather than the human resources department. McColgan explains how FIRSCo overcame resistance to this sweeping change in employee education. (Time was one obstacle: each associate receives 80 hours of training per year.) In addition, the author discusses the fine art of measuring the success of a program like SDU. She finds that the company's investment has paid dividends to the staff, to the organization as a whole, and to FIRSCo's customers.

Fidelity to the housing first model and effectiveness of permanent supported housing programs in California.

PubMed

Gilmer, Todd P; Stefancic, Ana; Katz, Marian L; Sklar, Marisa; Tsemberis, Sam; Palinkas, Lawrence A

2014-11-01

Permanent supported housing programs are being implemented throughout the United States. This study examined the relationship between fidelity to the Housing First model and residential outcomes among clients of full service partnerships (FSPs) in California. This study had a mixed-methods design. Quantitative administrative and survey data were used to describe FSP practices and to examine the association between fidelity to Housing First and residential outcomes in the year before and after enrollment of 6,584 FSP clients in 86 programs. Focus groups at 20 FSPs provided qualitative data to enhance the understanding of these findings with actual accounts of housing-related experiences in high- and low-fidelity programs. Prior to enrollment, the mean days of homelessness were greater at high- versus low-fidelity (101 versus 46 days) FSPs. After adjustment for individual characteristics, the analysis found that days spent homeless after enrollment declined by 87 at high-fidelity programs and by 34 at low-fidelity programs. After adjustment for days spent homeless before enrollment, days spent homeless after enrollment declined by 63 at high-fidelity programs and by 53 at low-fidelity programs. After enrollment, clients at high-fidelity programs spent more than 60 additional days in apartments than clients at low-facility programs. Differences were found between high- and low-fidelity FSPs in client choice in housing and how much clients' goals were considered in housing placement. Programs with greater fidelity to the Housing First model enrolled clients with longer histories of homelessness and placed most of them in apartments.

Integration of the virtual model of a Stewart platform with the avatar of a vehicle in a virtual reality

NASA Astrophysics Data System (ADS)

Herbuś, K.; Ociepka, P.

2016-08-01

The development of methods of computer aided design and engineering allows conducting virtual tests, among others concerning motion simulation of technical means. The paper presents a method of integrating an object in the form of a virtual model of a Stewart platform with an avatar of a vehicle moving in a virtual environment. The area of the problem includes issues related to the problem of fidelity of mapping the work of the analyzed technical mean. The main object of investigations is a 3D model of a Stewart platform, which is a subsystem of the simulator designated for driving learning for disabled persons. The analyzed model of the platform, prepared for motion simulation, was created in the “Motion Simulation” module of a CAD/CAE class system Siemens PLM NX. Whereas the virtual environment, in which the moves the avatar of the passenger car, was elaborated in a VR class system EON Studio. The element integrating both of the mentioned software environments is a developed application that reads information from the virtual reality (VR) concerning the current position of the car avatar. Then, basing on the accepted algorithm, it sends control signals to respective joints of the model of the Stewart platform (CAD).

The Validity and Incremental Validity of Knowledge Tests, Low-Fidelity Simulations, and High-Fidelity Simulations for Predicting Job Performance in Advanced-Level High-Stakes Selection

ERIC Educational Resources Information Center

Lievens, Filip; Patterson, Fiona

2011-01-01

In high-stakes selection among candidates with considerable domain-specific knowledge and experience, investigations of whether high-fidelity simulations (assessment centers; ACs) have incremental validity over low-fidelity simulations (situational judgment tests; SJTs) are lacking. Therefore, this article integrates research on the validity of…

A multi-fidelity framework for physics based rotor blade simulation and optimization

NASA Astrophysics Data System (ADS)

Collins, Kyle Brian

New helicopter rotor designs are desired that offer increased efficiency, reduced vibration, and reduced noise. Rotor Designers in industry need methods that allow them to use the most accurate simulation tools available to search for these optimal designs. Computer based rotor analysis and optimization have been advanced by the development of industry standard codes known as "comprehensive" rotorcraft analysis tools. These tools typically use table look-up aerodynamics, simplified inflow models and perform aeroelastic analysis using Computational Structural Dynamics (CSD). Due to the simplified aerodynamics, most design studies are performed varying structural related design variables like sectional mass and stiffness. The optimization of shape related variables in forward flight using these tools is complicated and results are viewed with skepticism because rotor blade loads are not accurately predicted. The most accurate methods of rotor simulation utilize Computational Fluid Dynamics (CFD) but have historically been considered too computationally intensive to be used in computer based optimization, where numerous simulations are required. An approach is needed where high fidelity CFD rotor analysis can be utilized in a shape variable optimization problem with multiple objectives. Any approach should be capable of working in forward flight in addition to hover. An alternative is proposed and founded on the idea that efficient hybrid CFD methods of rotor analysis are ready to be used in preliminary design. In addition, the proposed approach recognizes the usefulness of lower fidelity physics based analysis and surrogate modeling. Together, they are used with high fidelity analysis in an intelligent process of surrogate model building of parameters in the high fidelity domain. Closing the loop between high and low fidelity analysis is a key aspect of the proposed approach. This is done by using information from higher fidelity analysis to improve predictions made with lower fidelity models. This thesis documents the development of automated low and high fidelity physics based rotor simulation frameworks. The low fidelity framework uses a comprehensive code with simplified aerodynamics. The high fidelity model uses a parallel processor capable CFD/CSD methodology. Both low and high fidelity frameworks include an aeroacoustic simulation for prediction of noise. A synergistic process is developed that uses both the low and high fidelity frameworks together to build approximate models of important high fidelity metrics as functions of certain design variables. To test the process, a 4-bladed hingeless rotor model is used as a baseline. The design variables investigated include tip geometry and spanwise twist distribution. Approximation models are built for metrics related to rotor efficiency and vibration using the results from 60+ high fidelity (CFD/CSD) experiments and 400+ low fidelity experiments. Optimization using the approximation models found the Pareto Frontier anchor points, or the design having maximum rotor efficiency and the design having minimum vibration. Various Pareto generation methods are used to find designs on the frontier between these two anchor designs. When tested in the high fidelity framework, the Pareto anchor designs are shown to be very good designs when compared with other designs from the high fidelity database. This provides evidence that the process proposed has merit. Ultimately, this process can be utilized by industry rotor designers with their existing tools to bring high fidelity analysis into the preliminary design stage of rotors. In conclusion, the methods developed and documented in this thesis have made several novel contributions. First, an automated high fidelity CFD based forward flight simulation framework has been built for use in preliminary design optimization. The framework was built around an integrated, parallel processor capable CFD/CSD/AA process. Second, a novel method of building approximate models of high fidelity parameters has been developed. The method uses a combination of low and high fidelity results and combines Design of Experiments, statistical effects analysis, and aspects of approximation model management. And third, the determination of rotor blade shape variables through optimization using CFD based analysis in forward flight has been performed. This was done using the high fidelity CFD/CSD/AA framework and method mentioned above. While the low and high fidelity predictions methods used in the work still have inaccuracies that can affect the absolute levels of the results, a framework has been successfully developed and demonstrated that allows for an efficient process to improve rotor blade designs in terms of a selected choice of objective function(s). Using engineering judgment, this methodology could be applied today to investigate opportunities to improve existing designs. With improvements in the low and high fidelity prediction components that will certainly occur, this framework could become a powerful tool for future rotorcraft design work. (Abstract shortened by UMI.)

Understanding Optimal Decision-Making in Wargaming

DTIC Science & Technology

2013-09-01

of which is a better understanding of the impact of decisions as a part of combat processes. However, using wargaming to understand decision-making...Raymond, 1989). In the aviation domain, pilots exhibit different visual scanning patterns during various phases of flying under instrument flight rules ( IFR ...human neuro- science, 7, 2013. Anna Skinner, Chris Berka, Lindsay Ohara-Long, and Marc Sebrechts. Impact of virtual en- vironment fidelity on behavioral

Understanding Optimal Decision-Making in Wargaming

DTIC Science & Technology

2013-10-01

beneficial outcomes from wargaming, one of which is a better understanding of the impact of decisions as a part of combat processes. However, using...under instrument flight rules ( IFR ) (Bellenkes et al., 1997; Katoh, 1997). Of note, eye-tracking technology also has been applied to investigate...Neuroscience, 7 . Skinner, A., Berka, C., Ohara-Long, L., & Sebrechts, M. (2010). Impact of Virtual En- vironment Fidelity on Behavioral and

Virtual Transgenics: Using a Molecular Biology Simulation to Impact Student Academic Achievement and Attitudes

NASA Astrophysics Data System (ADS)

Shegog, Ross; Lazarus, Melanie M.; Murray, Nancy G.; Diamond, Pamela M.; Sessions, Nathalie; Zsigmond, Eva

2012-10-01

The transgenic mouse model is useful for studying the causes and potential cures for human genetic diseases. Exposing high school biology students to laboratory experience in developing transgenic animal models is logistically prohibitive. Computer-based simulation, however, offers this potential in addition to advantages of fidelity and reach. This study describes and evaluates a computer-based simulation to train advanced placement high school science students in laboratory protocols, a transgenic mouse model was produced. A simulation module on preparing a gene construct in the molecular biology lab was evaluated using a randomized clinical control design with advanced placement high school biology students in Mercedes, Texas ( n = 44). Pre-post tests assessed procedural and declarative knowledge, time on task, attitudes toward computers for learning and towards science careers. Students who used the simulation increased their procedural and declarative knowledge regarding molecular biology compared to those in the control condition (both p < 0.005). Significant increases continued to occur with additional use of the simulation ( p < 0.001). Students in the treatment group became more positive toward using computers for learning ( p < 0.001). The simulation did not significantly affect attitudes toward science in general. Computer simulation of complex transgenic protocols have potential to provide a "virtual" laboratory experience as an adjunct to conventional educational approaches.

Real-time mandibular angle reduction surgical simulation with haptic rendering.

PubMed

Wang, Qiong; Chen, Hui; Wu, Wen; Jin, Hai-Yang; Heng, Pheng-Ann

2012-11-01

Mandibular angle reduction is a popular and efficient procedure widely used to alter the facial contour. The primary surgical instruments, the reciprocating saw and the round burr, employed in the surgery have a common feature: operating at a high-speed. Generally, inexperienced surgeons need a long-time practice to learn how to minimize the risks caused by the uncontrolled contacts and cutting motions in manipulation of instruments with high-speed reciprocation or rotation. A virtual reality-based surgical simulator for the mandibular angle reduction was designed and implemented on a CUDA-based platform in this paper. High-fidelity visual and haptic feedbacks are provided to enhance the perception in a realistic virtual surgical environment. The impulse-based haptic models were employed to simulate the contact forces and torques on the instruments. It provides convincing haptic sensation for surgeons to control the instruments under different reciprocation or rotation velocities. The real-time methods for bone removal and reconstruction during surgical procedures have been proposed to support realistic visual feedbacks. The simulated contact forces were verified by comparing against the actual force data measured through the constructed mechanical platform. An empirical study based on the patient-specific data was conducted to evaluate the ability of the proposed system in training surgeons with various experiences. The results confirm the validity of our simulator.

Numerical Zooming Between a NPSS Engine System Simulation and a One-Dimensional High Compressor Analysis Code

NASA Technical Reports Server (NTRS)

Follen, Gregory; auBuchon, M.

2000-01-01

Within NASA's High Performance Computing and Communication (HPCC) program, NASA Glenn Research Center is developing an environment for the analysis/design of aircraft engines called the Numerical Propulsion System Simulation (NPSS). NPSS focuses on the integration of multiple disciplines such as aerodynamics, structures, and heat transfer along with the concept of numerical zooming between zero-dimensional to one-, two-, and three-dimensional component engine codes. In addition, the NPSS is refining the computing and communication technologies necessary to capture complex physical processes in a timely and cost-effective manner. The vision for NPSS is to create a "numerical test cell" enabling full engine simulations overnight on cost-effective computing platforms. Of the different technology areas that contribute to the development of the NPSS Environment, the subject of this paper is a discussion on numerical zooming between a NPSS engine simulation and higher fidelity representations of the engine components (fan, compressor, burner, turbines, etc.). What follows is a description of successfully zooming one-dimensional (row-by-row) high-pressure compressor analysis results back to a zero-dimensional NPSS engine simulation and a discussion of the results illustrated using an advanced data visualization tool. This type of high fidelity system-level analysis, made possible by the zooming capability of the NPSS, will greatly improve the capability of the engine system simulation and increase the level of virtual test conducted prior to committing the design to hardware.

The use of virtual reality tools in surgical education.

PubMed

Smith, Andrew

2010-03-01

Advances in computing, specifically those used for simulation and games technology has allowed for exciting developments in dental and surgical education. At the same time concerns are being raised that students with relatively little training, practise to improve their skill on patients with all of the inherent risks that may occur. Simulation in dentistry has been practised for many years and so the concept is not new to the profession. New tools have been developed that both enhance teaching and learning and are also useful for assessment of students and trainees. The challenge of virtual and simulated reality tools is to have the required fidelity to improve teaching and learning outcomes over the currently utilized methodology.

High-Fidelity Simulations of Electromagnetic Propagation and RF Communication Systems

DTIC Science & Technology

2017-05-01

addition to high -fidelity RF propagation modeling, lower-fidelity mod- els, which are less computationally burdensome, are available via a C++ API...expensive to perform, requiring roughly one hour of computer time with 36 available cores and ray tracing per- formed by a single high -end GPU...ER D C TR -1 7- 2 Military Engineering Applied Research High -Fidelity Simulations of Electromagnetic Propagation and RF Communication

Synaptic noise is an information bottleneck in the inner retina during dynamic visual stimulation

PubMed Central

Freed, Michael A; Liang, Zhiyin

2014-01-01

In daylight, noise generated by cones determines the fidelity with which visual signals are initially encoded. Subsequent stages of visual processing require synapses from bipolar cells to ganglion cells, but whether these synapses generate a significant amount of noise was unknown. To characterize noise generated by these synapses, we recorded excitatory postsynaptic currents from mammalian retinal ganglion cells and subjected them to a computational noise analysis. The release of transmitter quanta at bipolar cell synapses contributed substantially to the noise variance found in the ganglion cell, causing a significant loss of fidelity from bipolar cell array to postsynaptic ganglion cell. Virtually all the remaining noise variance originated in the presynaptic circuit. Circuit noise had a frequency content similar to noise shared by ganglion cells but a very different frequency content from noise from bipolar cell synapses, indicating that these synapses constitute a source of independent noise not shared by ganglion cells. These findings contribute a picture of daylight retinal circuits where noise from cones and noise generated by synaptic transmission of cone signals significantly limit visual fidelity. PMID:24297850

Implementation fidelity trajectories of a health promotion program in multidisciplinary settings: managing tensions in rehabilitation care.

PubMed

Hoekstra, Femke; van Offenbeek, Marjolein A G; Dekker, Rienk; Hettinga, Florentina J; Hoekstra, Trynke; van der Woude, Lucas H V; van der Schans, Cees P

2017-12-01

Although the importance of evaluating implementation fidelity is acknowledged, little is known about heterogeneity in fidelity over time. This study aims to generate insight into the heterogeneity in implementation fidelity trajectories of a health promotion program in multidisciplinary settings and the relationship with changes in patients' health behavior. This study used longitudinal data from the nationwide implementation of an evidence-informed physical activity promotion program in Dutch rehabilitation care. Fidelity scores were calculated based on annual surveys filled in by involved professionals (n = ± 70). Higher fidelity scores indicate a more complete implementation of the program's core components. A hierarchical cluster analysis was conducted on the implementation fidelity scores of 17 organizations at three different time points. Quantitative and qualitative data were used to explore organizational and professional differences between identified trajectories. Regression analyses were conducted to determine differences in patient outcomes. Three trajectories were identified as the following: 'stable high fidelity' (n = 9), 'moderate and improving fidelity' (n = 6), and 'unstable fidelity' (n = 2). The stable high fidelity organizations were generally smaller, started earlier, and implemented the program in a more structured way compared to moderate and improving fidelity organizations. At the implementation period's start and end, support from physicians and physiotherapists, professionals' appreciation, and program compatibility were rated more positively by professionals working in stable high fidelity organizations as compared to the moderate and improving fidelity organizations (p < .05). Qualitative data showed that the stable high fidelity organizations had often an explicit vision and strategy about the implementation of the program. Intriguingly, the trajectories were not associated with patients' self-reported physical activity outcomes (adjusted model β = - 651.6, t(613) = - 1032, p = .303). Differences in organizational-level implementation fidelity trajectories did not result in outcome differences at patient-level. This suggests that an effective implementation fidelity trajectory is contingent on the local organization's conditions. More specifically, achieving stable high implementation fidelity required the management of tensions: realizing a localized change vision, while safeguarding the program's standardized core components and engaging the scarce physicians throughout the process. When scaling up evidence-informed health promotion programs, we propose to tailor the management of implementation tensions to local organizations' starting position, size, and circumstances. The Netherlands National Trial Register NTR3961 . Registered 18 April 2013.

The Need for High Fidelity Lunar Regolith Simulants

NASA Technical Reports Server (NTRS)

Gaier, James R.

2007-01-01

The case is made for the need to have high fidelity lunar regolith simulants to verify the performance of structures and mechanisms to be used on the lunar surface. Minor constituents will in some cases have major consequences. Small amounts of sulfur in the regolith can poison catalysts, and metallic iron on the surface of nano-sized dust particles may cause a dramatic increase in its toxicity. So the definition of a high fidelity simulant is application dependent. For example, in situ resource utilization will require high fidelity in chemistry, meaning careful attention to the minor components and phases; but some other applications, such as the abrasive effects on suit fabrics, might be relatively insensitive to minor component chemistry. The lunar environment itself will change the surface chemistry of the simulant, so to have a high fidelity simulant at must be used in a high fidelity simulated environment to get a high fidelity simulation. Research must be conducted to determine how sensitive technologies will be to minor components and environmental factors before they can be dismissed as unimportant.

Design and development of a virtual reality simulator for advanced cardiac life support training.

PubMed

Vankipuram, Akshay; Khanal, Prabal; Ashby, Aaron; Vankipuram, Mithra; Gupta, Ashish; DrummGurnee, Denise; Josey, Karen; Smith, Marshall

2014-07-01

The use of virtual reality (VR) training tools for medical education could lead to improvements in the skills of clinicians while providing economic incentives for healthcare institutions. The use of VR tools can also mitigate some of the drawbacks currently associated with providing medical training in a traditional clinical environment such as scheduling conflicts and the need for specialized equipment (e.g., high-fidelity manikins). This paper presents the details of the framework and the development methodology associated with a VR-based training simulator for advanced cardiac life support, a time critical, team-based medical scenario. In addition, we also report the key findings of a usability study conducted to assess the efficacy of various features of this VR simulator through a postuse questionnaire administered to various care providers. The usability questionnaires were completed by two groups that used two different versions of the VR simulator. One version consisted of the VR trainer with it all its features and a minified version with certain immersive features disabled. We found an increase in usability scores from the minified group to the full VR group.

Tangible display systems: direct interfaces for computer-based studies of surface appearance

NASA Astrophysics Data System (ADS)

Darling, Benjamin A.; Ferwerda, James A.

2010-02-01

When evaluating the surface appearance of real objects, observers engage in complex behaviors involving active manipulation and dynamic viewpoint changes that allow them to observe the changing patterns of surface reflections. We are developing a class of tangible display systems to provide these natural modes of interaction in computer-based studies of material perception. A first-generation tangible display was created from an off-the-shelf laptop computer containing an accelerometer and webcam as standard components. Using these devices, custom software estimated the orientation of the display and the user's viewing position. This information was integrated with a 3D rendering module so that rotating the display or moving in front of the screen would produce realistic changes in the appearance of virtual objects. In this paper, we consider the design of a second-generation system to improve the fidelity of the virtual surfaces rendered to the screen. With a high-quality display screen and enhanced tracking and rendering capabilities, a secondgeneration system will be better able to support a range of appearance perception applications.

The role of simulation in neurosurgery.

PubMed

Rehder, Roberta; Abd-El-Barr, Muhammad; Hooten, Kristopher; Weinstock, Peter; Madsen, Joseph R; Cohen, Alan R

2016-01-01

In an era of residency duty-hour restrictions, there has been a recent effort to implement simulation-based training methods in neurosurgery teaching institutions. Several surgical simulators have been developed, ranging from physical models to sophisticated virtual reality systems. To date, there is a paucity of information describing the clinical benefits of existing simulators and the assessment strategies to help implement them into neurosurgical curricula. Here, we present a systematic review of the current models of simulation and discuss the state-of-the-art and future directions for simulation in neurosurgery. Retrospective literature review. Multiple simulators have been developed for neurosurgical training, including those for minimally invasive procedures, vascular, skull base, pediatric, tumor resection, functional neurosurgery, and spine surgery. The pros and cons of existing systems are reviewed. Advances in imaging and computer technology have led to the development of different simulation models to complement traditional surgical training. Sophisticated virtual reality (VR) simulators with haptic feedback and impressive imaging technology have provided novel options for training in neurosurgery. Breakthrough training simulation using 3D printing technology holds promise for future simulation practice, proving high-fidelity patient-specific models to complement residency surgical learning.

VERA Core Simulator methodology for pressurized water reactor cycle depletion

DOE PAGES

Kochunas, Brendan; Collins, Benjamin; Stimpson, Shane; ...

2017-01-12

This paper describes the methodology developed and implemented in the Virtual Environment for Reactor Applications Core Simulator (VERA-CS) to perform high-fidelity, pressurized water reactor (PWR), multicycle, core physics calculations. Depletion of the core with pin-resolved power and nuclide detail is a significant advance in the state of the art for reactor analysis, providing the level of detail necessary to address the problems of the U.S. Department of Energy Nuclear Reactor Simulation Hub, the Consortium for Advanced Simulation of Light Water Reactors (CASL). VERA-CS has three main components: the neutronics solver MPACT, the thermal-hydraulic (T-H) solver COBRA-TF (CTF), and the nuclidemore » transmutation solver ORIGEN. This paper focuses on MPACT and provides an overview of the resonance self-shielding methods, macroscopic-cross-section calculation, two-dimensional/one-dimensional (2-D/1-D) transport, nuclide depletion, T-H feedback, and other supporting methods representing a minimal set of the capabilities needed to simulate high-fidelity models of a commercial nuclear reactor. Results are presented from the simulation of a model of the first cycle of Watts Bar Unit 1. The simulation is within 16 parts per million boron (ppmB) reactivity for all state points compared to cycle measurements, with an average reactivity bias of <5 ppmB for the entire cycle. Comparisons to cycle 1 flux map data are also provided, and the average 2-D root-mean-square (rms) error during cycle 1 is 1.07%. To demonstrate the multicycle capability, a state point at beginning of cycle (BOC) 2 was also simulated and compared to plant data. The comparison of the cycle 2 BOC state has a reactivity difference of +3 ppmB from measurement, and the 2-D rms of the comparison in the flux maps is 1.77%. Lastly, these results provide confidence in VERA-CS’s capability to perform high-fidelity calculations for practical PWR reactor problems.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kochunas, Brendan; Collins, Benjamin; Stimpson, Shane

This paper describes the methodology developed and implemented in the Virtual Environment for Reactor Applications Core Simulator (VERA-CS) to perform high-fidelity, pressurized water reactor (PWR), multicycle, core physics calculations. Depletion of the core with pin-resolved power and nuclide detail is a significant advance in the state of the art for reactor analysis, providing the level of detail necessary to address the problems of the U.S. Department of Energy Nuclear Reactor Simulation Hub, the Consortium for Advanced Simulation of Light Water Reactors (CASL). VERA-CS has three main components: the neutronics solver MPACT, the thermal-hydraulic (T-H) solver COBRA-TF (CTF), and the nuclidemore » transmutation solver ORIGEN. This paper focuses on MPACT and provides an overview of the resonance self-shielding methods, macroscopic-cross-section calculation, two-dimensional/one-dimensional (2-D/1-D) transport, nuclide depletion, T-H feedback, and other supporting methods representing a minimal set of the capabilities needed to simulate high-fidelity models of a commercial nuclear reactor. Results are presented from the simulation of a model of the first cycle of Watts Bar Unit 1. The simulation is within 16 parts per million boron (ppmB) reactivity for all state points compared to cycle measurements, with an average reactivity bias of <5 ppmB for the entire cycle. Comparisons to cycle 1 flux map data are also provided, and the average 2-D root-mean-square (rms) error during cycle 1 is 1.07%. To demonstrate the multicycle capability, a state point at beginning of cycle (BOC) 2 was also simulated and compared to plant data. The comparison of the cycle 2 BOC state has a reactivity difference of +3 ppmB from measurement, and the 2-D rms of the comparison in the flux maps is 1.77%. Lastly, these results provide confidence in VERA-CS’s capability to perform high-fidelity calculations for practical PWR reactor problems.« less

Deterministic transfer of an unknown qutrit state assisted by the low-Q microwave resonators

NASA Astrophysics Data System (ADS)

Liu, Tong; Zhang, Yang; Yu, Chang-Shui; Zhang, Wei-Ning

2017-05-01

Qutrits (i.e., three-level quantum systems) can be used to achieve many quantum information and communication tasks due to their large Hilbert spaces. In this work, we propose a scheme to transfer an unknown quantum state between two flux qutrits coupled to two superconducting coplanar waveguide resonators. The quantum state transfer can be deterministically achieved without measurements. Because resonator photons are virtually excited during the operation time, the decoherences caused by the resonator decay and the unwanted inter-resonator crosstalk are greatly suppressed. Moreover, our approach can be adapted to other solid-state qutrits coupled to circuit resonators. Numerical simulations show that the high-fidelity transfer of quantum state between the two qutrits is feasible with current circuit QED technology.

Mapping ASTI patient’s therapeutic-data model to virtual Medical Record: can VMR represent therapeutic data elements used by ASTI in clinical guideline implementations?

PubMed Central

Ebrahiminia, Vahid; Yasini, Mobin; Lamy, Jean Baptiste

2013-01-01

Lack of interoperability between health information systems is a major obstacle in implementing Clinical decision supports systems (CDSS) and their widespread disseminations. Virtual Medical Record (vMR) proposed by HL7 is a common data model for representing clinical information Inputs and outputs that can be used by CDSS and local clinical systems. A CDSS called ASTI used a similar model to represent clinical data and therapeutic history of patient. In order to evaluate the compatibility of ASTI with vMR, we started to map the ASTI model of representing patient’s therapeutic data to vMR. We compared the data elements and associated terminologies used in ASTI and vMR and we evaluated the semantic fidelity between the models. Only one data element the qualitative description of drug dosage, did not match the vMR model. However, it can be calculated in the execution engine. The semantic fidelity was satisfactorily preserved in 12 of 17 elements mapped between the models. This model of ASTI seems compatible to vMR. Further work is necessary to evaluate the compatibility of clinical data model of ASTI to vMR and the use of vMR in implementing practice guidelines. PMID:24551344

An experimental study on fear of public speaking using a virtual environment.

PubMed

Slater, Mel; Pertaub, David-Paul; Barker, Chris; Clark, David M

2006-10-01

This paper examines a necessary condition for successful exploitation of a virtual environment (VE) in therapeutic intervention for fear of public speaking. The condition is that clients experience a degree of anxiety in the VE that is similar to what they would have been expected to experience in a similar real world setting. We refer to this as a "presence" response. The experimental study involved 20 people who were confident public speakers and 16 who were phobic, assessed on a standard psychological scale. Half of each group spoke within a VE depicting an empty seminar room, and the other half within the same room but populated by a neutrally behaving virtual audience of five people. Three responses were measured--a questionnaire-based measure of anxiety, a measure of self-focused attention on somatic responses, and actual heart rate. On all responses, the people with phobia showed a significant increase in signs of anxiety when speaking to the virtual audience compared to the empty room, whereas the confident people did not. The result was strong in spite of the relatively low representational and behavioral fidelity of the virtual characters.

A unified, multifidelity quasi-newton optimization method with application to aero-structural designa

NASA Astrophysics Data System (ADS)

Bryson, Dean Edward

A model's level of fidelity may be defined as its accuracy in faithfully reproducing a quantity or behavior of interest of a real system. Increasing the fidelity of a model often goes hand in hand with increasing its cost in terms of time, money, or computing resources. The traditional aircraft design process relies upon low-fidelity models for expedience and resource savings. However, the reduced accuracy and reliability of low-fidelity tools often lead to the discovery of design defects or inadequacies late in the design process. These deficiencies result either in costly changes or the acceptance of a configuration that does not meet expectations. The unknown opportunity cost is the discovery of superior vehicles that leverage phenomena unknown to the designer and not illuminated by low-fidelity tools. Multifidelity methods attempt to blend the increased accuracy and reliability of high-fidelity models with the reduced cost of low-fidelity models. In building surrogate models, where mathematical expressions are used to cheaply approximate the behavior of costly data, low-fidelity models may be sampled extensively to resolve the underlying trend, while high-fidelity data are reserved to correct inaccuracies at key locations. Similarly, in design optimization a low-fidelity model may be queried many times in the search for new, better designs, with a high-fidelity model being exercised only once per iteration to evaluate the candidate design. In this dissertation, a new multifidelity, gradient-based optimization algorithm is proposed. It differs from the standard trust region approach in several ways, stemming from the new method maintaining an approximation of the inverse Hessian, that is the underlying curvature of the design problem. Whereas the typical trust region approach performs a full sub-optimization using the low-fidelity model at every iteration, the new technique finds a suitable descent direction and focuses the search along it, reducing the number of low-fidelity evaluations required. This narrowing of the search domain also alleviates the burden on the surrogate model corrections between the low- and high-fidelity data. Rather than requiring the surrogate to be accurate in a hyper-volume bounded by the trust region, the model needs only to be accurate along the forward-looking search direction. Maintaining the approximate inverse Hessian also allows the multifidelity algorithm to revert to high-fidelity optimization at any time. In contrast, the standard approach has no memory of the previously-computed high-fidelity data. The primary disadvantage of the proposed algorithm is that it may require modifications to the optimization software, whereas standard optimizers may be used as black-box drivers in the typical trust region method. A multifidelity, multidisciplinary simulation of aeroelastic vehicle performance is developed to demonstrate the optimization method. The numerical physics models include body-fitted Euler computational fluid dynamics; linear, panel aerodynamics; linear, finite-element computational structural mechanics; and reduced, modal structural bases. A central element of the multifidelity, multidisciplinary framework is a shared parametric, attributed geometric representation that ensures the analysis inputs are consistent between disciplines and fidelities. The attributed geometry also enables the transfer of data between disciplines. The new optimization algorithm, a standard trust region approach, and a single-fidelity quasi-Newton method are compared for a series of analytic test functions, using both polynomial chaos expansions and kriging to correct discrepancies between fidelity levels of data. In the aggregate, the new method requires fewer high-fidelity evaluations than the trust region approach in 51% of cases, and the same number of evaluations in 18%. The new approach also requires fewer low-fidelity evaluations, by up to an order of magnitude, in almost all cases. The efficacy of both multifidelity methods compared to single-fidelity optimization depends significantly on the behavior of the high-fidelity model and the quality of the low-fidelity approximation, though savings are realized in a large number of cases. The multifidelity algorithm is also compared to the single-fidelity quasi-Newton method for complex aeroelastic simulations. The vehicle design problem includes variables for planform shape, structural sizing, and cruise condition with constraints on trim and structural stresses. Considering the objective function reduction versus computational expenditure, the multifidelity process performs better in three of four cases in early iterations. However, the enforcement of a contracting trust region slows the multifidelity progress. Even so, leveraging the approximate inverse Hessian, the optimization can be seamlessly continued using high-fidelity data alone. Ultimately, the proposed new algorithm produced better designs in all four cases. Investigating the return on investment in terms of design improvement per computational hour confirms that the multifidelity advantage is greatest in early iterations, and managing the transition to high-fidelity optimization is critical.

A randomized controlled study of manikin simulator fidelity on neonatal resuscitation program learning outcomes.

PubMed

Curran, Vernon; Fleet, Lisa; White, Susan; Bessell, Clare; Deshpandey, Akhil; Drover, Anne; Hayward, Mark; Valcour, James

2015-03-01

The neonatal resuscitation program (NRP) has been developed to educate physicians and other health care providers about newborn resuscitation and has been shown to improve neonatal resuscitation skills. Simulation-based training is recommended as an effective modality for instructing neonatal resuscitation and both low and high-fidelity manikin simulators are used. There is limited research that has compared the effect of low and high-fidelity manikin simulators for NRP learning outcomes, and more specifically on teamwork performance and confidence. The purpose of this study was to examine the effect of using low versus high-fidelity manikin simulators in NRP instruction. A randomized posttest-only control group study design was conducted. Third year undergraduate medical students participated in NRP instruction and were assigned to an experimental group (high-fidelity manikin simulator) or control group (low-fidelity manikin simulator). Integrated skills station (megacode) performance, participant satisfaction, confidence and teamwork behaviour scores were compared between the study groups. Participants in the high-fidelity manikin simulator instructional group reported significantly higher total scores in overall satisfaction (p = 0.001) and confidence (p = 0.001). There were no significant differences in teamwork behaviour scores, as observed by two independent raters, nor differences on mandatory integrated skills station performance items at the p < 0.05 level. Medical students' reported greater satisfaction and confidence with high-fidelity manikin simulators, but did not demonstrate overall significantly improved teamwork or integrated skills station performance. Low and high-fidelity manikin simulators facilitate similar levels of objectively measured NRP outcomes for integrated skills station and teamwork performance.

The Use of Virtual Reality in Psychology: A Case Study in Visual Perception

PubMed Central

Wilson, Christopher J.; Soranzo, Alessandro

2015-01-01

Recent proliferation of available virtual reality (VR) tools has seen increased use in psychological research. This is due to a number of advantages afforded over traditional experimental apparatus such as tighter control of the environment and the possibility of creating more ecologically valid stimulus presentation and response protocols. At the same time, higher levels of immersion and visual fidelity afforded by VR do not necessarily evoke presence or elicit a “realistic” psychological response. The current paper reviews some current uses for VR environments in psychological research and discusses some ongoing questions for researchers. Finally, we focus on the area of visual perception, where both the advantages and challenges of VR are particularly salient. PMID:26339281

High Fidelity System Simulation of Multiple Components in Support of the UEET Program

NASA Technical Reports Server (NTRS)

Plybon, Ronald C.; VanDeWall, Allan; Sampath, Rajiv; Balasubramaniam, Mahadevan; Mallina, Ramakrishna; Irani, Rohinton

2006-01-01

The High Fidelity System Simulation effort has addressed various important objectives to enable additional capability within the NPSS framework. The scope emphasized High Pressure Turbine and High Pressure Compressor components. Initial effort was directed at developing and validating intermediate fidelity NPSS model using PD geometry and extended to high-fidelity NPSS model by overlaying detailed geometry to validate CFD against rig data. Both "feedforward" and feedback" approaches of analysis zooming was employed to enable system simulation capability in NPSS. These approaches have certain benefits and applicability in terms of specific applications "feedback" zooming allows the flow-up of information from high-fidelity analysis to be used to update the NPSS model results by forcing the NPSS solver to converge to high-fidelity analysis predictions. This apporach is effective in improving the accuracy of the NPSS model; however, it can only be used in circumstances where there is a clear physics-based strategy to flow up the high-fidelity analysis results to update the NPSS system model. "Feed-forward" zooming approach is more broadly useful in terms of enabling detailed analysis at early stages of design for a specified set of critical operating points and using these analysis results to drive design decisions early in the development process.

Design and implementation of a 3D ocean virtual reality and visualization engine

NASA Astrophysics Data System (ADS)

Chen, Ge; Li, Bo; Tian, Fenglin; Ji, Pengbo; Li, Wenqing

2012-12-01

In this study, a 3D virtual reality and visualization engine for rendering the ocean, named VV-Ocean, is designed for marine applications. The design goals of VV-Ocean aim at high fidelity simulation of ocean environment, visualization of massive and multidimensional marine data, and imitation of marine lives. VV-Ocean is composed of five modules, i.e. memory management module, resources management module, scene management module, rendering process management module and interaction management module. There are three core functions in VV-Ocean: reconstructing vivid virtual ocean scenes, visualizing real data dynamically in real time, imitating and simulating marine lives intuitively. Based on VV-Ocean, we establish a sea-land integration platform which can reproduce drifting and diffusion processes of oil spilling from sea bottom to surface. Environment factors such as ocean current and wind field have been considered in this simulation. On this platform oil spilling process can be abstracted as movements of abundant oil particles. The result shows that oil particles blend with water well and the platform meets the requirement for real-time and interactive rendering. VV-Ocean can be widely used in ocean applications such as demonstrating marine operations, facilitating maritime communications, developing ocean games, reducing marine hazards, forecasting the weather over oceans, serving marine tourism, and so on. Finally, further technological improvements of VV-Ocean are discussed.

An interactive physics-based unmanned ground vehicle simulator leveraging open source gaming technology: progress in the development and application of the virtual autonomous navigation environment (VANE) desktop

NASA Astrophysics Data System (ADS)

Rohde, Mitchell M.; Crawford, Justin; Toschlog, Matthew; Iagnemma, Karl D.; Kewlani, Guarav; Cummins, Christopher L.; Jones, Randolph A.; Horner, David A.

2009-05-01

It is widely recognized that simulation is pivotal to vehicle development, whether manned or unmanned. There are few dedicated choices, however, for those wishing to perform realistic, end-to-end simulations of unmanned ground vehicles (UGVs). The Virtual Autonomous Navigation Environment (VANE), under development by US Army Engineer Research and Development Center (ERDC), provides such capabilities but utilizes a High Performance Computing (HPC) Computational Testbed (CTB) and is not intended for on-line, real-time performance. A product of the VANE HPC research is a real-time desktop simulation application under development by the authors that provides a portal into the HPC environment as well as interaction with wider-scope semi-automated force simulations (e.g. OneSAF). This VANE desktop application, dubbed the Autonomous Navigation Virtual Environment Laboratory (ANVEL), enables analysis and testing of autonomous vehicle dynamics and terrain/obstacle interaction in real-time with the capability to interact within the HPC constructive geo-environmental CTB for high fidelity sensor evaluations. ANVEL leverages rigorous physics-based vehicle and vehicle-terrain interaction models in conjunction with high-quality, multimedia visualization techniques to form an intuitive, accurate engineering tool. The system provides an adaptable and customizable simulation platform that allows developers a controlled, repeatable testbed for advanced simulations. ANVEL leverages several key technologies not common to traditional engineering simulators, including techniques from the commercial video-game industry. These enable ANVEL to run on inexpensive commercial, off-the-shelf (COTS) hardware. In this paper, the authors describe key aspects of ANVEL and its development, as well as several initial applications of the system.

The Need for High Fidelity Lunar Regolith Simulants

NASA Technical Reports Server (NTRS)

Gaier, James R.

2008-01-01

The case is made for the need to have high fidelity lunar regolith simulants to verify the performance of structures, mechanisms, and processes to be used on the lunar surface. Minor constituents will in some cases have major consequences. Small amounts of sulfur in the regolith can poison catalysts, and metallic iron on the surface of nano-sized dust particles may cause a dramatic increase in its toxicity. So the definition of a high fidelity simulant is application-dependent. For example, in situ resource utilization will require high fidelity in chemistry, meaning careful attention to the minor components and phases; but some other applications, such as the abrasive effects on suit fabrics, might be relatively insensitive to minor component chemistry while abrasion of some metal components may be highly dependent on trace components. The lunar environment itself will change the surface chemistry of the simulant, so to have a high fidelity simulant it must be used in a high fidelity simulated environment to get an accurate simulation. Research must be conducted to determine how sensitive technologies will be to minor components and environmental factors before they can be dismissed as unimportant.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Weina; Hellinga, Homme W.; Beese, Lorena S.

Even though high-fidelity polymerases copy DNA with remarkable accuracy, some base-pair mismatches are incorporated at low frequency, leading to spontaneous mutagenesis. Using high-resolution X-ray crystallographic analysis of a DNA polymerase that catalyzes replication in crystals, we observe that a C {center_dot} A mismatch can mimic the shape of cognate base pairs at the site of incorporation. This shape mimicry enables the mismatch to evade the error detection mechanisms of the polymerase, which would normally either prevent mismatch incorporation or promote its nucleolytic excision. Movement of a single proton on one of the mismatched bases alters the hydrogen-bonding pattern such thatmore » a base pair forms with an overall shape that is virtually indistinguishable from a canonical, Watson-Crick base pair in double-stranded DNA. These observations provide structural evidence for the rare tautomer hypothesis of spontaneous mutagenesis, a long-standing concept that has been difficult to demonstrate directly.« less

Economical Unsteady High-Fidelity Aerodynamics for Structural Optimization with a Flutter Constraint

NASA Technical Reports Server (NTRS)

Bartels, Robert E.; Stanford, Bret K.

2017-01-01

Structural optimization with a flutter constraint for a vehicle designed to fly in the transonic regime is a particularly difficult task. In this speed range, the flutter boundary is very sensitive to aerodynamic nonlinearities, typically requiring high-fidelity Navier-Stokes simulations. However, the repeated application of unsteady computational fluid dynamics to guide an aeroelastic optimization process is very computationally expensive. This expense has motivated the development of methods that incorporate aspects of the aerodynamic nonlinearity, classical tools of flutter analysis, and more recent methods of optimization. While it is possible to use doublet lattice method aerodynamics, this paper focuses on the use of an unsteady high-fidelity aerodynamic reduced order model combined with successive transformations that allows for an economical way of utilizing high-fidelity aerodynamics in the optimization process. This approach is applied to the common research model wing structural design. As might be expected, the high-fidelity aerodynamics produces a heavier wing than that optimized with doublet lattice aerodynamics. It is found that the optimized lower skin of the wing using high-fidelity aerodynamics differs significantly from that using doublet lattice aerodynamics.

Information in the Biosphere: Biological and Digital Worlds.

PubMed

Gillings, Michael R; Hilbert, Martin; Kemp, Darrell J

2016-03-01

Evolution has transformed life through key innovations in information storage and replication, including RNA, DNA, multicellularity, and culture and language. We argue that the carbon-based biosphere has generated a cognitive system (humans) capable of creating technology that will result in a comparable evolutionary transition. Digital information has reached a similar magnitude to information in the biosphere. It increases exponentially, exhibits high-fidelity replication, evolves through differential fitness, is expressed through artificial intelligence (AI), and has facility for virtually limitless recombination. Like previous evolutionary transitions, the potential symbiosis between biological and digital information will reach a critical point where these codes could compete via natural selection. Alternatively, this fusion could create a higher-level superorganism employing a low-conflict division of labor in performing informational tasks. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Use of Virtual Reality in the Study of People's Responses to Violent Incidents.

PubMed

Rovira, Aitor; Swapp, David; Spanlang, Bernhard; Slater, Mel

2009-01-01

This paper reviews experimental methods for the study of the responses of people to violence in digital media, and in particular considers the issues of internal validity and ecological validity or generalisability of results to events in the real world. Experimental methods typically involve a significant level of abstraction from reality, with participants required to carry out tasks that are far removed from violence in real life, and hence their ecological validity is questionable. On the other hand studies based on field data, while having ecological validity, cannot control multiple confounding variables that may have an impact on observed results, so that their internal validity is questionable. It is argued that immersive virtual reality may provide a unification of these two approaches. Since people tend to respond realistically to situations and events that occur in virtual reality, and since virtual reality simulations can be completely controlled for experimental purposes, studies of responses to violence within virtual reality are likely to have both ecological and internal validity. This depends on a property that we call 'plausibility' - including the fidelity of the depicted situation with prior knowledge and expectations. We illustrate this with data from a previously published experiment, a virtual reprise of Stanley Milgram's 1960s obedience experiment, and also with pilot data from a new study being developed that looks at bystander responses to violent incidents.

The Use of Virtual Reality in the Study of People's Responses to Violent Incidents

PubMed Central

Rovira, Aitor; Swapp, David; Spanlang, Bernhard; Slater, Mel

2009-01-01

This paper reviews experimental methods for the study of the responses of people to violence in digital media, and in particular considers the issues of internal validity and ecological validity or generalisability of results to events in the real world. Experimental methods typically involve a significant level of abstraction from reality, with participants required to carry out tasks that are far removed from violence in real life, and hence their ecological validity is questionable. On the other hand studies based on field data, while having ecological validity, cannot control multiple confounding variables that may have an impact on observed results, so that their internal validity is questionable. It is argued that immersive virtual reality may provide a unification of these two approaches. Since people tend to respond realistically to situations and events that occur in virtual reality, and since virtual reality simulations can be completely controlled for experimental purposes, studies of responses to violence within virtual reality are likely to have both ecological and internal validity. This depends on a property that we call ‘plausibility’ – including the fidelity of the depicted situation with prior knowledge and expectations. We illustrate this with data from a previously published experiment, a virtual reprise of Stanley Milgram's 1960s obedience experiment, and also with pilot data from a new study being developed that looks at bystander responses to violent incidents. PMID:20076762

The Human Dimension of Closing the Training Gap for Fifth-Generation Fighters

NASA Technical Reports Server (NTRS)

Hoke, Jaclyn; Postnikov, Alex; Schnell, Thomas

2012-01-01

Based on a review of the recent technical literature there is little question that a serious training gap exists for fifth-generation fighters, primarily arising from the need to provide their own red-air. There are several methods for reducing this gap, including injecting virtual and constructive threats into the live cockpit. This live-virtual-constructive (LVC) training approach provides a cost effective means for addressing training needs but faces several challenges. Technical challenges include data links and information assurance. A more serious challenge may be the human factors dimension of representing virtual and constructive entities in the cockpit while ensuring safety-of-flight. This also needs to happen without increasing pilot workload. This paper discusses the methods Rockwell Collins and the University of Iowa's Operator Performance Lab use to assess pilot workload and training fidelity measures in an LVC training environment and the research we are conducting in safety-of-flight requirements of integrated LVC symbology.

Concept Maps: A Tool to Prepare for High Fidelity Simulation in Nursing

ERIC Educational Resources Information Center

Daley, Barbara J.; Beman, Sarah Black; Morgan, Sarah; Kennedy, Linda; Sheriff, Mandy

2017-01-01

In this study, the use of concept mapping as a method to prepare for high fidelity simulated learning experiences was investigated. Fourth year baccalaureate nursing students were taught how to use concept maps as a way to prepare for high fidelity simulated nursing experiences. Students prepared concept maps for two simulated experiences…

A Comparative Analysis of 2D and 3D Tasks for Virtual Reality Therapies Based on Robotic-Assisted Neurorehabilitation for Post-stroke Patients

PubMed Central

Lledó, Luis D.; Díez, Jorge A.; Bertomeu-Motos, Arturo; Ezquerro, Santiago; Badesa, Francisco J.; Sabater-Navarro, José M.; García-Aracil, Nicolás

2016-01-01

Post-stroke neurorehabilitation based on virtual therapies are performed completing repetitive exercises shown in visual electronic devices, whose content represents imaginary or daily life tasks. Currently, there are two ways of visualization of these task. 3D virtual environments are used to get a three dimensional space that represents the real world with a high level of detail, whose realism is determinated by the resolucion and fidelity of the objects of the task. Furthermore, 2D virtual environments are used to represent the tasks with a low degree of realism using techniques of bidimensional graphics. However, the type of visualization can influence the quality of perception of the task, affecting the patient's sensorimotor performance. The purpose of this paper was to evaluate if there were differences in patterns of kinematic movements when post-stroke patients performed a reach task viewing a virtual therapeutic game with two different type of visualization of virtual environment: 2D and 3D. Nine post-stroke patients have participated in the study receiving a virtual therapy assisted by PUPArm rehabilitation robot. Horizontal movements of the upper limb were performed to complete the aim of the tasks, which consist in reaching peripheral or perspective targets depending on the virtual environment shown. Various parameter types such as the maximum speed, reaction time, path length, or initial movement are analyzed from the data acquired objectively by the robotic device to evaluate the influence of the task visualization. At the end of the study, a usability survey was provided to each patient to analysis his/her satisfaction level. For all patients, the movement trajectories were enhanced when they completed the therapy. This fact suggests that patient's motor recovery was increased. Despite of the similarity in majority of the kinematic parameters, differences in reaction time and path length were higher using the 3D task. Regarding the success rates were very similar. In conclusion, the using of 2D environments in virtual therapy may be a more appropriate and comfortable way to perform tasks for upper limb rehabilitation of post-stroke patients, in terms of accuracy in order to effectuate optimal kinematic trajectories. PMID:27616992

Optimization and evaluation of T7 based RNA linear amplification protocols for cDNA microarray analysis

PubMed Central

Zhao, Hongjuan; Hastie, Trevor; Whitfield, Michael L; Børresen-Dale, Anne-Lise; Jeffrey, Stefanie S

2002-01-01

Background T7 based linear amplification of RNA is used to obtain sufficient antisense RNA for microarray expression profiling. We optimized and systematically evaluated the fidelity and reproducibility of different amplification protocols using total RNA obtained from primary human breast carcinomas and high-density cDNA microarrays. Results Using an optimized protocol, the average correlation coefficient of gene expression of 11,123 cDNA clones between amplified and unamplified samples is 0.82 (0.85 when a virtual array was created using repeatedly amplified samples to minimize experimental variation). Less than 4% of genes show changes in expression level by 2-fold or greater after amplification compared to unamplified samples. Most changes due to amplification are not systematic both within one tumor sample and between different tumors. Amplification appears to dampen the variation of gene expression for some genes when compared to unamplified poly(A)+ RNA. The reproducibility between repeatedly amplified samples is 0.97 when performed on the same day, but drops to 0.90 when performed weeks apart. The fidelity and reproducibility of amplification is not affected by decreasing the amount of input total RNA in the 0.3–3 micrograms range. Adding template-switching primer, DNA ligase, or column purification of double-stranded cDNA does not improve the fidelity of amplification. The correlation coefficient between amplified and unamplified samples is higher when total RNA is used as template for both experimental and reference RNA amplification. Conclusion T7 based linear amplification reproducibly generates amplified RNA that closely approximates original sample for gene expression profiling using cDNA microarrays. PMID:12445333

Sensor Spatial Distortion, Visual Latency, and Update Rate Effects on 3D Tracking in Virtual Environments

NASA Technical Reports Server (NTRS)

Ellis, S. R.; Adelstein, B. D.; Baumeler, S.; Jense, G. J.; Jacoby, R. H.; Trejo, Leonard (Technical Monitor)

1998-01-01

Several common defects that we have sought to minimize in immersing virtual environments are: static sensor spatial distortion, visual latency, and low update rates. Human performance within our environments during large amplitude 3D tracking was assessed by objective and subjective methods in the presence and absence of these defects. Results show that 1) removal of our relatively small spatial sensor distortion had minor effects on the tracking activity, 2) an Adapted Cooper-Harper controllability scale proved the most sensitive subjective indicator of the degradation of dynamic fidelity caused by increasing latency and decreasing frame rates, and 3) performance, as measured by normalized RMS tracking error or subjective impressions, was more markedly influenced by changing visual latency than by update rate.

The effect of high-fidelity patient simulation on the critical thinking and clinical decision-making skills of new graduate nurses.

PubMed

Maneval, Rhonda; Fowler, Kimberly A; Kays, John A; Boyd, Tiffany M; Shuey, Jennifer; Harne-Britner, Sarah; Mastrine, Cynthia

2012-03-01

This study was conducted to determine whether the addition of high-fidelity patient simulation to new nurse orientation enhanced critical thinking and clinical decision-making skills. A pretest-posttest design was used to assess critical thinking and clinical decision-making skills in two groups of graduate nurses. Compared with the control group, the high-fidelity patient simulation group did not show significant improvement in mean critical thinking or clinical decision-making scores. When mean scores were analyzed, both groups showed an increase in critical thinking scores from pretest to posttest, with the high-fidelity patient simulation group showing greater gains in overall scores. However, neither group showed a statistically significant increase in mean test scores. The effect of high-fidelity patient simulation on critical thinking and clinical decision-making skills remains unclear. Copyright 2012, SLACK Incorporated.

High-Fidelity Simulation for Neonatal Nursing Education: An Integrative Review of the Literature.

PubMed

Cooper, Allyson

2015-01-01

The lack of safe avenues to develop neonatal nursing competencies using human subjects leads to the notion that simulation education for neonatal nurses might be an ideal form of education. This integrative literature review compares traditional, teacher-centered education with high-fidelity simulation education for neonatal nurses. It examines the theoretical frameworks used in neonatal nursing education and outlines the advantages of this type of training, including improving communication and teamwork; providing an innovative pedagogical approach; and aiding in skill acquisition, confidence, and participant satisfaction. The importance of debriefing is also examined. High-fidelity simulation is not without disadvantages, including its significant cost, the time associated with training, the need for very complex technical equipment, and increased faculty resource requirements. Innovative uses of high-fidelity simulation in neonatal nursing education are suggested. High-fidelity simulation has great potential but requires additional research to fully prove its efficacy.

Virtual Treatment of Basilar Aneurysms Using Shape Memory Polymer Foam

PubMed Central

Ortega, J.M.; Hartman, J.; Rodriguez, J.N.; Maitland, D.J.

2013-01-01

Numerical simulations are performed on patient-specific basilar aneurysms that are treated with shape memory polymer (SMP) foam. In order to assess the post-treatment hemodynamics, two modeling approaches are employed. In the first, the foam geometry is obtained from a micro-CT scan and the pulsatile blood flow within the foam is simulated for both Newtonian and non-Newtonian viscosity models. In the second, the foam is represented as a porous media continuum, which has permeability properties that are determined by computing the pressure gradient through the foam geometry over a range of flow speeds comparable to those of in vivo conditions. Virtual angiography and additional post-processing demonstrate that the SMP foam significantly reduces the blood flow speed within the treated aneurysms, while eliminating the high-frequency velocity fluctuations that are present within the pre-treatment aneurysms. An estimation of the initial locations of thrombus formation throughout the SMP foam is obtained by means of a low fidelity thrombosis model that is based upon the residence time and shear rate of blood. The Newtonian viscosity model and the porous media model capture similar qualitative trends, though both yield a smaller volume of thrombus within the SMP foam. PMID:23329002

Virtual Treatment of Basilar Aneurysms Using Shape Memory Polymer Foam

NASA Astrophysics Data System (ADS)

Ortega, J. M.; Hartman, J.; Rodriguez, J. N.; Maitland, D. J.

2012-11-01

Numerical simulations are performed on patient-specific basilar aneurysms that are treated with shape memory polymer (SMP) foam. In order to assess the post-treatment hemodynamics, two modeling approaches are employed. In the first, the foam geometry is obtained from a micro-CT scan and the pulsatile blood flow within the foam is simulated for both Newtonian and non-Newtonian viscosity models. In the second, the foam is represented as a porous media continuum, which has permeability properties that are determined by computing the pressure gradient through the foam geometry over a range of flow speeds comparable to those of in vivo conditions. Virtual angiography and additional post-processing demonstrate that the SMP foam significantly reduces the blood flow speed within the treated aneurysms, while eliminating the high-frequency velocity fluctuations that are present prior to treatment. A prediction of the initial locations of thrombus formation throughout the SMP foam is obtained by means of a low fidelity thrombosis model that is based upon the residence time and shear rate of blood. The two modeling approaches capture similar qualitative trends for the initial locations of thrombus within the SMP foam.

Integrated multidisciplinary CAD/CAE environment for micro-electro-mechanical systems (MEMS)

NASA Astrophysics Data System (ADS)

Przekwas, Andrzej J.

1999-03-01

Computational design of MEMS involves several strongly coupled physical disciplines, including fluid mechanics, heat transfer, stress/deformation dynamics, electronics, electro/magneto statics, calorics, biochemistry and others. CFDRC is developing a new generation multi-disciplinary CAD systems for MEMS using high-fidelity field solvers on unstructured, solution-adaptive grids for a full range of disciplines. The software system, ACE + MEMS, includes all essential CAD tools; geometry/grid generation for multi- discipline, multi-equation solvers, GUI, tightly coupled configurable 3D field solvers for FVM, FEM and BEM and a 3D visualization/animation tool. The flow/heat transfer/calorics/chemistry equations are solved with unstructured adaptive FVM solver, stress/deformation are computed with a FEM STRESS solver and a FAST BEM solver is used to solve linear heat transfer, electro/magnetostatics and elastostatics equations on adaptive polygonal surface grids. Tight multidisciplinary coupling and automatic interoperability between the tools was achieved by designing a comprehensive database structure and APIs for complete model definition. The virtual model definition is implemented in data transfer facility, a publicly available tool described in this paper. The paper presents overall description of the software architecture and MEMS design flow in ACE + MEMS. It describes current status, ongoing effort and future plans for the software. The paper also discusses new concepts of mixed-level and mixed- dimensionality capability in which 1D microfluidic networks are simulated concurrently with 3D high-fidelity models of discrete components.

Foot-and-mouth disease virus type O specific mutations determine RNA-dependent RNA polymerase fidelity and virus attenuation.

PubMed

Li, Chen; Wang, Haiwei; Yuan, Tiangang; Woodman, Andrew; Yang, Decheng; Zhou, Guohui; Cameron, Craig E; Yu, Li

2018-05-01

Previous studies have shown that the FMDV Asia1/YS/CHA/05 high-fidelity mutagen-resistant variants are attenuated (Zeng et al., 2014). Here, we introduced the same single or multiple-amino-acid substitutions responsible for increased 3D pol fidelity of type Asia1 FMDV into the type O FMDV O/YS/CHA/05 infectious clone. The rescued viruses O-DA and O-DAMM are lower replication fidelity mutants and showed an attenuated phenotype. These results demonstrated that the same amino acid substitution of 3D pol in different serotypes of FMDV strains had different effects on viral fidelity. In addition, nucleoside analogues were used to select high-fidelity mutagen-resistant type O FMDV variants. The rescued mutagen-resistant type O FMDV high-fidelity variants exhibited significantly attenuated fitness and a reduced virulence phenotype. These results have important implications for understanding the molecular mechanism of FMDV evolution and pathogenicity, especially in developing a safer modified live-attenuated vaccine against FMDV. Copyright © 2018 Elsevier Inc. All rights reserved.

[Existing laparoscopic simulators and their benefit for the surgeon].

PubMed

Kalvach, J; Ryska, O; Ryska, M

2016-01-01

Nowadays, laparoscopic operations are a common part of surgical practice. However, they have their own characteristics and require a specific method of preparation. Recently, simulation techniques have been increasingly used for the training of skills. The aim of this review is to provide a summary of available literature on the topic of laparoscopic simulators, to assess their contribution to the training of surgeons, and to identify the most effective type of simulation. PubMed database, Web of Science and Cochrane Library were used to search for relevant publications. The keywords "laparoscopy, simulator, surgery, assessment" were used in the search. The search was limited to prospective studies published in the last 5 years in the English language. From a total of 354 studies found, we included in the survey 26 that matched our criteria. Nine studies compared individual simulators to one another. Five studies evaluated "high and low fidelity" (a virtual box simulator) as equally effective (EBM 2a). In three cases the "low fidelity" box simulator was found to be more efficient (EBM 2a3b). Only one study preferred the virtual simulator (VR) (EBM2b).Thirteen studies evaluated the benefits of simulators for practice. Twelve found training on a simulator to be an effective method of preparation (EBM 1b3b). In contrast, one study did not find any difference between the training simulator and traditional preparation (EBM 3b). Nine studies evaluated directly one of the methods of evaluating laparoscopic skills. Three studies evaluated VR simulator as a useful assessment tool. Other studies evaluated as successful the scoring system GOALS-GH. The hand motion analysis model was successful in one case. Most studies were observational (EBM 3b) and only 2 studies were of higher quality (EBM 2b). Simulators are an effective tool for practicing laparoscopic techniques (EBM: 1b). It cannot be determined based on available data which of the simulators is most effective. The virtual simulator, however, still remains the most self-sufficient unit suitable for teaching as well as evaluation of laparoscopic techniques (EBM 2b3b). Further studies are needed to find an effective system and parameters for an objective evaluation of skills. laparoscopy - simulator - surgery assessment.

Cultured High-Fidelity Three-Dimensional Human Urogenital Tract Carcinomas and Process

NASA Technical Reports Server (NTRS)

Goodwin, Thomas J. (Inventor); Prewett, Tacey L. (Inventor); Spaulding, Glenn F. (Inventor); Wolf, David A. (Inventor)

1998-01-01

Artificial high-fidelity three-dimensional human urogenital tract carcinomas are propagated under in vitro-microgravity conditions from carcinoma cells. Artificial high-fidelity three-dimensional human urogenital tract carcinomas are also propagated from a coculture of normal urogenital tract cells inoculated with carcinoma cells. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

An Automatic Medium to High Fidelity Low-Thrust Global Trajectory Toolchain; EMTG-GMAT

NASA Technical Reports Server (NTRS)

Beeson, Ryne T.; Englander, Jacob A.; Hughes, Steven P.; Schadegg, Maximillian

2015-01-01

Solving the global optimization, low-thrust, multiple-flyby interplanetary trajectory problem with high-fidelity dynamical models requires an unreasonable amount of computational resources. A better approach, and one that is demonstrated in this paper, is a multi-step process whereby the solution of the aforementioned problem is solved at a lower-fidelity and this solution is used as an initial guess for a higher-fidelity solver. The framework presented in this work uses two tools developed by NASA Goddard Space Flight Center: the Evolutionary Mission Trajectory Generator (EMTG) and the General Mission Analysis Tool (GMAT). EMTG is a medium to medium-high fidelity low-thrust interplanetary global optimization solver, which now has the capability to automatically generate GMAT script files for seeding a high-fidelity solution using GMAT's local optimization capabilities. A discussion of the dynamical models as well as thruster and power modeling for both EMTG and GMAT are given in this paper. Current capabilities are demonstrated with examples that highlight the toolchains ability to efficiently solve the difficult low-thrust global optimization problem with little human intervention.

The impact of constructive feedback on training in gastrointestinal endoscopy using high-fidelity Virtual-Reality simulation: a randomised controlled trial.

PubMed

Kruglikova, Irina; Grantcharov, Teodor P; Drewes, Asbjorn M; Funch-Jensen, Peter

2010-02-01

Recently, virtual reality computer simulators have been used to enhance traditional endoscopy teaching. Previous studies have demonstrated construct validity of these systems and transfer of virtual skills to the operating room. However, to date no simulator-training curricula have been designed and there is very little evidence on the impact of external feedback on acquisition of endoscopic skills. The aim of the present study was to assess the impact of external feedback on the learning curves on a VR colonoscopy simulator using inexperienced trainees. 22 trainees, without colonoscopy experience were randomised to a group which received structured feedback provided by an experienced supervisor and a controlled group. All participants performed 15 repetitions of task 3 from the Introduction colonoscopy module of the Accu Touch Endoscopy simulator. Retention/transfer tests on simulator were performed 4-6 weeks after the last repetition. The proficiency levels were based on the performance of eight experienced colonoscopists. All subjects were able to complete the procedure on the simulator. There were no perforations in the feedback group versus seven in the non-feedback group. Subjects in the feedback group reached expert proficiency levels in percentage of mucosa visualised and time to reach the caecum significantly faster compared with the control group. None of the groups demonstrated significant degradation of performance in simulator retention/transfer tests. Concurrent feedback given by supervisor concur an advantage in acquisition of basic colonoscopy skills and achieving of proficiency level as compared to independent training.

A virtual reality patient simulation system for teaching emergency response skills to U.S. Navy medical providers.

PubMed

Freeman, K M; Thompson, S F; Allely, E B; Sobel, A L; Stansfield, S A; Pugh, W M

2001-01-01

Rapid and effective medical intervention in response to civil and military-related disasters is crucial for saving lives and limiting long-term disability. Inexperienced providers may suffer in performance when faced with limited supplies and the demands of stabilizing casualties not generally encountered in the comparatively resource-rich hospital setting. Head trauma and multiple injury cases are particularly complex to diagnose and treat, requiring the integration and processing of complex multimodal data. In this project, collaborators adapted and merged existing technologies to produce a flexible, modular patient simulation system with both three-dimensional virtual reality and two-dimensional flat screen user interfaces for teaching cognitive assessment and treatment skills. This experiential, problem-based training approach engages the user in a stress-filled, high fidelity world, providing multiple learning opportunities within a compressed period of time and without risk. The system simulates both the dynamic state of the patient and the results of user intervention, enabling trainees to watch the virtual patient deteriorate or stabilize as a result of their decision-making speed and accuracy. Systems can be deployed to the field enabling trainees to practice repeatedly until their skills are mastered and to maintain those skills once acquired. This paper describes the technologies and the process used to develop the trainers, the clinical algorithms, and the incorporation of teaching points. We also characterize aspects of the actual simulation exercise through the lens of the trainee.

Nonlinear High Fidelity Aeroelastic Analysis for Novel Configurations

DTIC Science & Technology

2010-03-29

Blm +B nl m ) ζ (14) δǫm = ( Blm +B nl m ) δζ (15) χ = Bbζ (16) δχ = Bbδζ . (17) Substitution of Eqs. 13-17 into Eq. 11 gives: δζT ( h...S ΨTFdS + ∫ S ΨTΦtrdS − h ∫ S ΨTΨρdSζ̈ − h ∫ S ΨT cΨdSζ̇ − ∫ S ( Blm ) TNdS − ∫ S (Bnlm) TNdS − ∫ S BTb MdS ) = 0 . (18) Considering the arbitrariness...of the virtual generalized displacements, Eq. 18 can be written 6 of 24 as: h ∫ S ΨTΨρdSζ̈ + h ∫ S ΨT cΨdSζ̇ + ∫ S ( Blm ) TNdS + ∫ S (Bnlm) TNdS+ ∫

The development of a virtual reality training programme for ophthalmology: repeatability and reproducibility (part of the International Forum for Ophthalmic Simulation Studies).

PubMed

Saleh, G M; Theodoraki, K; Gillan, S; Sullivan, P; O'Sullivan, F; Hussain, B; Bunce, C; Athanasiadis, I

2013-11-01

To evaluate the variability of performance among novice ophthalmic trainees in a range of repeated tasks using the Eyesi virtual reality (VR) simulator. Eighteen subjects undertook three attempts of five cataract specific and generic three-dimensional tasks: continuous curvilinear capsulorhexis, cracking and chopping, cataract navigation, bimanual cataract training, anti-tremor. Scores for each attempt were out of a maximum of 100 points. A non-parametric test was used to analyse the data, where a P-value of <0.05 was considered statistically significant. Highly significant differences were found between the scores achieved in the first attempt and that during the second (P<0.0001) and third (P<0.0001) but not between the second and third attempt (P=0.65). There was no significant variability in the overall score between the users (P=0.1104) or in the difference between their highest and lowest score (P=0.3878). Highly significant differences between tasks were shown both in the overall score (P=0.0001) and in the difference between highest and lowest score (P=0.003). This study, which is the first to quantify reproducibility of performance in entry level trainees using a VR tool, demonstrated significant intra-novice variability. The cohort of subjects performed equally overall in the range of tasks (no inter-novice variability) but each showed that performance varies significantly with the complexity of the task when using this high-fidelity instrument.

Multi-fidelity methods for uncertainty quantification in transport problems

NASA Astrophysics Data System (ADS)

Tartakovsky, G.; Yang, X.; Tartakovsky, A. M.; Barajas-Solano, D. A.; Scheibe, T. D.; Dai, H.; Chen, X.

2016-12-01

We compare several multi-fidelity approaches for uncertainty quantification in flow and transport simulations that have a lower computational cost than the standard Monte Carlo method. The cost reduction is achieved by combining a small number of high-resolution (high-fidelity) simulations with a large number of low-resolution (low-fidelity) simulations. We propose a new method, a re-scaled Multi Level Monte Carlo (rMLMC) method. The rMLMC is based on the idea that the statistics of quantities of interest depends on scale/resolution. We compare rMLMC with existing multi-fidelity methods such as Multi Level Monte Carlo (MLMC) and reduced basis methods and discuss advantages of each approach.

High versus Low Theoretical Fidelity Pedometer Intervention Using Social-Cognitive Theory on Steps and Self-Efficacy

ERIC Educational Resources Information Center

Raedeke, Thomas D.; Dlugonski, Deirdre

2017-01-01

Purpose: This study was designed to compare a low versus high theoretical fidelity pedometer intervention applying social-cognitive theory on step counts and self-efficacy. Method: Fifty-six public university employees participated in a 10-week randomized controlled trial with 2 conditions that varied in theoretical fidelity. Participants in the…

Creation of a Rapid High-Fidelity Aerodynamics Module for a Multidisciplinary Design Environment

NASA Technical Reports Server (NTRS)

Srinivasan, Muktha; Whittecar, William; Edwards, Stephen; Mavris, Dimitri N.

2012-01-01

In the traditional aerospace vehicle design process, each successive design phase is accompanied by an increment in the modeling fidelity of the disciplinary analyses being performed. This trend follows a corresponding shrinking of the design space as more and more design decisions are locked in. The correlated increase in knowledge about the design and decrease in design freedom occurs partly because increases in modeling fidelity are usually accompanied by significant increases in the computational expense of performing the analyses. When running high fidelity analyses, it is not usually feasible to explore a large number of variations, and so design space exploration is reserved for conceptual design, and higher fidelity analyses are run only once a specific point design has been selected to carry forward. The designs produced by this traditional process have been recognized as being limited by the uncertainty that is present early on due to the use of lower fidelity analyses. For example, uncertainty in aerodynamics predictions produces uncertainty in trajectory optimization, which can impact overall vehicle sizing. This effect can become more significant when trajectories are being shaped by active constraints. For example, if an optimal trajectory is running up against a normal load factor constraint, inaccuracies in the aerodynamic coefficient predictions can cause a feasible trajectory to be considered infeasible, or vice versa. For this reason, a trade must always be performed between the desired fidelity and the resources available. Apart from this trade between fidelity and computational expense, it is very desirable to use higher fidelity analyses earlier in the design process. A large body of work has been performed to this end, led by efforts in the area of surrogate modeling. In surrogate modeling, an up-front investment is made by running a high fidelity code over a Design of Experiments (DOE); once completed, the DOE data is used to create a surrogate model, which captures the relationships between input variables and responses into regression equations. Depending on the dimensionality of the problem and the fidelity of the code for which a surrogate model is being created, the initial DOE can itself be computationally prohibitive to run. Cokriging, a modeling approach from the field of geostatistics, provides a desirable compromise between computational expense and fidelity. To do this, cokriging leverages a large body of data generated by a low fidelity analysis, combines it with a smaller set of data from a higher fidelity analysis, and creates a kriging surrogate model with prediction fidelity approaching that of the higher fidelity analysis. When integrated into a multidisciplinary environment, a disciplinary analysis module employing cokriging can raise the analysis fidelity without drastically impacting the expense of design iterations. This is demonstrated through the creation of an aerodynamics analysis module in NASA s OpenMDAO framework. Aerodynamic analyses including Missile DATCOM, APAS, and USM3D are leveraged to create high fidelity aerodynamics decks for parametric vehicle geometries, which are created in NASA s Vehicle Sketch Pad (VSP). Several trade studies are performed to examine the achieved level of model fidelity, and the overall impact to vehicle design is quantified.

[A new concept in digestive surgery: the computer assisted surgical procedure, from virtual reality to telemanipulation].

PubMed

Marescaux, J; Clément, J M; Nord, M; Russier, Y; Tassetti, V; Mutter, D; Cotin, S; Ayache, N

1997-11-01

Surgical simulation increasingly appears to be an essential aspect of tomorrow's surgery. The development of a hepatic surgery simulator is an advanced concept calling for a new writing system which will transform the medical world: virtual reality. Virtual reality extends the perception of our five senses by representing more than the real state of things by the means of computer sciences and robotics. It consists of three concepts: immersion, navigation and interaction. Three reasons have led us to develop this simulator: the first is to provide the surgeon with a comprehensive visualisation of the organ. The second reason is to allow for planning and surgical simulation that could be compared with the detailed flight-plan for a commercial jet pilot. The third lies in the fact that virtual reality is an integrated part of the concept of computer assisted surgical procedure. The project consists of a sophisticated simulator which has to include five requirements: visual fidelity, interactivity, physical properties, physiological properties, sensory input and output. In this report we will describe how to get a realistic 3D model of the liver from bi-dimensional 2D medical images for anatomical and surgical training. The introduction of a tumor and the consequent planning and virtual resection is also described, as are force feedback and real-time interaction.

High-fidelity in vivo replication of DNA base shape mimics without Watson–Crick hydrogen bonds

PubMed Central

Delaney, James C.; Henderson, Paul T.; Helquist, Sandra A.; Morales, Juan C.; Essigmann, John M.; Kool, Eric T.

2003-01-01

We report studies testing the importance of Watson–Crick hydrogen bonding, base-pair geometry, and steric effects during DNA replication in living bacterial cells. Nonpolar DNA base shape mimics of thymine and adenine (abbreviated F and Q, respectively) were introduced into Escherichia coli by insertion into a phage genome followed by transfection of the vector into bacteria. Genetic assays showed that these two base mimics were bypassed with moderate to high efficiency in the cells and with very high efficiency under damage-response (SOS induction) conditions. Under both sets of conditions, the T-shape mimic (F) encoded genetic information in the bacteria as if it were thymine, directing incorporation of adenine opposite it with high fidelity. Similarly, the A mimic (Q) directed incorporation of thymine opposite itself with high fidelity. The data establish that Watson–Crick hydrogen bonding is not necessary for high-fidelity replication of a base pair in vivo. The results suggest that recognition of DNA base shape alone serves as the most powerful determinant of fidelity during transfer of genetic information in a living organism. PMID:12676985

High Fidelity Simulation of Atomization in Diesel Engine Sprays

DTIC Science & Technology

2015-09-01

ARL-RP-0555 ● SEP 2015 US Army Research Laboratory High Fidelity Simulation of Atomization in Diesel Engine Sprays by L Bravo...ARL-RP-0555 ● SEP 2015 US Army Research Laboratory High Fidelity Simulation of Atomization in Diesel Engine Sprays by L...Simulation of Atomization in Diesel Engine Sprays 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) L Bravo, CB Ivey, D

Implementation Fidelity in Community-Based Interventions

PubMed Central

Breitenstein, Susan M.; Gross, Deborah; Garvey, Christine; Hill, Carri; Fogg, Louis; Resnick, Barbara

2012-01-01

Implementation fidelity is the degree to which an intervention is delivered as intended and is critical to successful translation of evidence-based interventions into practice. Diminished fidelity may be why interventions that work well in highly controlled trials may fail to yield the same outcomes when applied in real life contexts. The purpose of this paper is to define implementation fidelity and describe its importance for the larger science of implementation, discuss data collection methods and current efforts in measuring implementation fidelity in community-based prevention interventions, and present future research directions for measuring implementation fidelity that will advance implementation science. PMID:20198637

NPSS Multidisciplinary Integration and Analysis

NASA Technical Reports Server (NTRS)

Hall, Edward J.; Rasche, Joseph; Simons, Todd A.; Hoyniak, Daniel

2006-01-01

The objective of this task was to enhance the capability of the Numerical Propulsion System Simulation (NPSS) by expanding its reach into the high-fidelity multidisciplinary analysis area. This task investigated numerical techniques to convert between cold static to hot running geometry of compressor blades. Numerical calculations of blade deformations were iteratively done with high fidelity flow simulations together with high fidelity structural analysis of the compressor blade. The flow simulations were performed with the Advanced Ducted Propfan Analysis (ADPAC) code, while structural analyses were performed with the ANSYS code. High fidelity analyses were used to evaluate the effects on performance of: variations in tip clearance, uncertainty in manufacturing tolerance, variable inlet guide vane scheduling, and the effects of rotational speed on the hot running geometry of the compressor blades.

Generation and applications of an ultrahigh-fidelity four-photon Greenberger-Horne-Zeilinger state.

PubMed

Zhang, Chao; Huang, Yun-Feng; Zhang, Cheng-Jie; Wang, Jian; Liu, Bi-Heng; Li, Chuan-Feng; Guo, Guang-Can

2016-11-28

High-quality entangled photon pairs generated via spontaneous parametric down-conversion have made great contributions to the modern quantum information science and the fundamental tests of quantum mechanics. However, the quality of the entangled states decreases sharply when moving from biphoton to multiphoton experiments, mainly due to the lack of interactions between photons. Here, for the first time, we generate a four-photon Greenberger-Horne-Zeilinger state with a fidelity of 98%, which is even comparable to the best fidelity of biphoton entangled states. Thus, it enables us to demonstrate an ultrahigh-fidelity entanglement swapping-the key ingredient in various quantum information tasks. Our results push the fidelity of multiphoton entanglement generation to a new level and would be useful in some demanding tasks, e.g., we successfully demonstrate the genuine multipartite nonlocality of the observed state in the nonsignaling scenario by violating a novel Hardy-like inequality, which requires very high state-fidelity.

Design, Realization, and First Validation of an Immersive Web-Based Virtual Patient Simulator for Training Clinical Decisions in Surgery.

PubMed

Kleinert, Robert; Heiermann, Nadine; Wahba, Roger; Chang, De-Huan; Hölscher, Arnulf H; Stippel, Dirk L

2015-01-01

Immersive patient simulators (IPS) allow an illusionary immersion into a synthetic world where the user can freely navigate through a 3-dimensional environment similar to computer games. Playful learning with IPS allows internalization of medical workflows without harming real patients. Ideally, IPS show high student acceptance and can have positive effect on knowledge gain. Development of IPS with high technical quality is resource intensive. Therefore most of the "high-fidelity" IPS are commercially driven. Usage of IPS in the daily curriculum is still rare. There is no academic-driven simulator that is freely accessible to every student and combines high immersion grade with a profound amount of medical content. Therefore it was our aim to develop an academic-driven IPS prototype that is free to use and combines a high immersion grade with profound medical content. In addition, a first validation of the prototype was conducted. The conceptual design included definition of the following parameters: amount of curricular content, grade of technical quality, availability, and level of validation. A preliminary validation was done with 25 students. Students' opinion about acceptance was evaluated by a Likert-scale questionnaire. Effect on knowledge gain was determined by testing concordance and predictive validity. A custom-made simulator prototype (Artificial learning interface for clinical education [ALICE]) displays a virtual clinic environment that can be explored from a first-person view similar to a video game. By controlling an avatar, the user navigates through the environment, is able to treat virtual patients, and faces the consequence of different decisions. ALICE showed high students' acceptance. There was positive correlation for concordance validity and predictive validity. Simulator usage had positive effect on reproduction of trained content and declarative knowledge. We successfully developed a university-based, IPS prototype (ALICE) with profound medical content. ALICE is a nonprofit simulator, easy to use, and showed high students' acceptance; thus it potentially provides an additional tool for supporting student teaching in the daily clinical curriculum. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Mechatronic design of haptic forceps for robotic surgery.

PubMed

Rizun, P; Gunn, D; Cox, B; Sutherland, G

2006-12-01

Haptic feedback increases operator performance and comfort during telerobotic manipulation. Feedback of grasping pressure is critical in many microsurgical tasks, yet no haptic interface for surgical tools is commercially available. Literature on the psychophysics of touch was reviewed to define the spectrum of human touch perception and the fidelity requirements of an ideal haptic interface. Mechanical design and control literature was reviewed to translate the psychophysical requirements to engineering specification. High-fidelity haptic forceps were then developed through an iterative process between engineering and surgery. The forceps are a modular device that integrate with a haptic hand controller to add force feedback for tool actuation in telerobotic or virtual surgery. Their overall length is 153 mm and their mass is 125 g. A contact-free voice coil actuator generates force feedback at frequencies up to 800 Hz. Maximum force output is 6 N (2N continuous) and the force resolution is 4 mN. The forceps employ a contact-free magnetic position sensor as well as micro-machined accelerometers to measure opening/closing acceleration. Position resolution is 0.6 microm with 1.3 microm RMS noise. The forceps can simulate stiffness greater than 20N/mm or impedances smaller than 15 g with no noticeable haptic artifacts or friction. As telerobotic surgery evolves, haptics will play an increasingly important role. Copyright 2006 John Wiley & Sons, Ltd.

Implementing a high-fidelity simulation program in a community college setting.

PubMed

Tuoriniemi, Pamela; Schott-Baer, Darlene

2008-01-01

Despite their relatively high cost, there is heightened interest by faculty in undergraduate nursing programs to implement high-fidelity simulation (HFS) programs. High-fidelity simulators are appealing because they allow students to experience high-risk, low-volume patient problems in a realistic setting. The decision to purchase a simulator is the first step in the process of implementing and maintaining an HFS lab. Knowledge, technical skill, commitment, and considerable time are needed to develop a successful program. The process, as experienced by one community college nursing program, is described.

Teaching elliptical excision skills to novice medical students: a randomized controlled study comparing low- and high-fidelity bench models.

PubMed

Denadai, Rafael; Oshiiwa, Marie; Saad-Hossne, Rogério

2014-03-01

The search for alternative and effective forms of training simulation is needed due to ethical and medico-legal aspects involved in training surgical skills on living patients, human cadavers and living animals. To evaluate if the bench model fidelity interferes in the acquisition of elliptical excision skills by novice medical students. Forty novice medical students were randomly assigned to 5 practice conditions with instructor-directed elliptical excision skills' training (n = 8): didactic materials (control); organic bench model (low-fidelity); ethylene-vinyl acetate bench model (low-fidelity); chicken legs' skin bench model (high-fidelity); or pig foot skin bench model (high-fidelity). Pre- and post-tests were applied. Global rating scale, effect size, and self-perceived confidence based on Likert scale were used to evaluate all elliptical excision performances. The analysis showed that after training, the students practicing on bench models had better performance based on Global rating scale (all P < 0.0000) and felt more confident to perform elliptical excision skills (all P < 0.0000) when compared to the control. There was no significant difference (all P > 0.05) between the groups that trained on bench models. The magnitude of the effect (basic cutaneous surgery skills' training) was considered large (>0.80) in all measurements. The acquisition of elliptical excision skills after instructor-directed training on low-fidelity bench models was similar to the training on high-fidelity bench models; and there was a more substantial increase in elliptical excision performances of students that trained on all simulators compared to the learning on didactic materials.

Electro-Optic Frequency Beam Splitters and Tritters for High-Fidelity Photonic Quantum Information Processing

DOE PAGES

Lu, Hsuan-Hao; Lukens, Joseph M.; Peters, Nicholas A.; ...

2018-01-18

In this paper, we report the experimental realization of high-fidelity photonic quantum gates for frequency-encoded qubits and qutrits based on electro-optic modulation and Fourier-transform pulse shaping. Our frequency version of the Hadamard gate offers near-unity fidelity (0.99998±0.00003), requires only a single microwave drive tone for near-ideal performance, functions across the entire C band (1530–1570 nm), and can operate concurrently on multiple qubits spaced as tightly as four frequency modes apart, with no observable degradation in the fidelity. For qutrits, we implement a 3×3 extension of the Hadamard gate: the balanced tritter. This tritter—the first ever demonstrated for frequency modes—attains fidelitymore » 0.9989±0.0004. Finally, these gates represent important building blocks toward scalable, high-fidelity quantum information processing based on frequency encoding.« less

Electro-Optic Frequency Beam Splitters and Tritters for High-Fidelity Photonic Quantum Information Processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Hsuan-Hao; Lukens, Joseph M.; Peters, Nicholas A.

In this paper, we report the experimental realization of high-fidelity photonic quantum gates for frequency-encoded qubits and qutrits based on electro-optic modulation and Fourier-transform pulse shaping. Our frequency version of the Hadamard gate offers near-unity fidelity (0.99998±0.00003), requires only a single microwave drive tone for near-ideal performance, functions across the entire C band (1530–1570 nm), and can operate concurrently on multiple qubits spaced as tightly as four frequency modes apart, with no observable degradation in the fidelity. For qutrits, we implement a 3×3 extension of the Hadamard gate: the balanced tritter. This tritter—the first ever demonstrated for frequency modes—attains fidelitymore » 0.9989±0.0004. Finally, these gates represent important building blocks toward scalable, high-fidelity quantum information processing based on frequency encoding.« less

Rotorcraft Research at the NASA Vertical Motion Simulator

NASA Technical Reports Server (NTRS)

Aponso, Bimal Lalith; Tran, Duc T.; Schroeder, Jeffrey A.

2009-01-01

In the 1970 s the role of the military helicopter evolved to encompass more demanding missions including low-level nap-of-the-earth flight and operation in severely degraded visual environments. The Vertical Motion Simulator (VMS) at the NASA Ames Research Center was built to provide a high-fidelity simulation capability to research new rotorcraft concepts and technologies that could satisfy these mission requirements. The VMS combines a high-fidelity large amplitude motion system with an adaptable simulation environment including interchangeable and configurable cockpits. In almost 30 years of operation, rotorcraft research on the VMS has contributed significantly to the knowledge-base on rotorcraft performance, handling qualities, flight control, and guidance and displays. These contributions have directly benefited current rotorcraft programs and flight safety. The high fidelity motion system in the VMS was also used to research simulation fidelity. This research provided a fundamental understanding of pilot cueing modalities and their effect on simulation fidelity.

First-Order Frameworks for Managing Models in Engineering Optimization

NASA Technical Reports Server (NTRS)

Alexandrov, Natlia M.; Lewis, Robert Michael

2000-01-01

Approximation/model management optimization (AMMO) is a rigorous methodology for attaining solutions of high-fidelity optimization problems with minimal expense in high- fidelity function and derivative evaluation. First-order AMMO frameworks allow for a wide variety of models and underlying optimization algorithms. Recent demonstrations with aerodynamic optimization achieved three-fold savings in terms of high- fidelity function and derivative evaluation in the case of variable-resolution models and five-fold savings in the case of variable-fidelity physics models. The savings are problem dependent but certain trends are beginning to emerge. We give an overview of the first-order frameworks, current computational results, and an idea of the scope of the first-order framework applicability.

The experiences of last-year student midwives with High-Fidelity Perinatal Simulation training: A qualitative descriptive study.

PubMed

Vermeulen, Joeri; Beeckman, Katrien; Turcksin, Rivka; Van Winkel, Lies; Gucciardo, Léonardo; Laubach, Monika; Peersman, Wim; Swinnen, Eva

2017-06-01

Simulation training is a powerful and evidence-based teaching method in healthcare. It allows students to develop essential competences that are often difficult to achieve during internships. High-Fidelity Perinatal Simulation exposes them to real-life scenarios in a safe environment. Although student midwives' experiences need to be considered to make the simulation training work, these have been overlooked so far. To explore the experiences of last-year student midwives with High-Fidelity Perinatal Simulation training. A qualitative descriptive study, using three focus group conversations with last-year student midwives (n=24). Audio tapes were transcribed and a thematic content analysis was performed. The entire data set was coded according to recurrent or common themes. To achieve investigator triangulation and confirm themes, discussions among the researchers was incorporated in the analysis. Students found High-Fidelity Perinatal Simulation training to be a positive learning method that increased both their competence and confidence. Their experiences varied over the different phases of the High-Fidelity Perinatal Simulation training. Although uncertainty, tension, confusion and disappointment were experienced throughout the simulation trajectory, they reported that this did not affect their learning and confidence-building. As High-Fidelity Perinatal Simulation training constitutes a helpful learning experience in midwifery education, it could have a positive influence on maternal and neonatal outcomes. In the long term, it could therefore enhance the midwifery profession in several ways. The present study is an important first step in opening up the debate about the pedagogical use of High-Fidelity Perinatal Simulation training within midwifery education. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

[Acquiring skills in malignant hyperthermia crisis management: comparison of high-fidelity simulation versus computer-based case study].

PubMed

Mejía, Vilma; Gonzalez, Carlos; Delfino, Alejandro E; Altermatt, Fernando R; Corvetto, Marcia A

The primary purpose of this study was to compare the effect of high fidelity simulation versus a computer-based case solving self-study, in skills acquisition about malignant hyperthermia on first year anesthesiology residents. After institutional ethical committee approval, 31 first year anesthesiology residents were enrolled in this prospective randomized single-blinded study. Participants were randomized to either a High Fidelity Simulation Scenario or a computer-based Case Study about malignant hyperthermia. After the intervention, all subjects' performance in was assessed through a high fidelity simulation scenario using a previously validated assessment rubric. Additionally, knowledge tests and a satisfaction survey were applied. Finally, a semi-structured interview was done to assess self-perception of reasoning process and decision-making. 28 first year residents finished successfully the study. Resident's management skill scores were globally higher in High Fidelity Simulation versus Case Study, however they were significant in 4 of the 8 performance rubric elements: recognize signs and symptoms (p = 0.025), prioritization of initial actions of management (p = 0.003), recognize complications (p = 0.025) and communication (p = 0.025). Average scores from pre- and post-test knowledge questionnaires improved from 74% to 85% in the High Fidelity Simulation group, and decreased from 78% to 75% in the Case Study group (p = 0.032). Regarding the qualitative analysis, there was no difference in factors influencing the student's process of reasoning and decision-making with both teaching strategies. Simulation-based training with a malignant hyperthermia high-fidelity scenario was superior to computer-based case study, improving knowledge and skills in malignant hyperthermia crisis management, with a very good satisfaction level in anesthesia residents. Copyright © 2018 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Middle-ear microsurgery simulation to improve new robotic procedures.

PubMed

Kazmitcheff, Guillaume; Nguyen, Yann; Miroir, Mathieu; Péan, Fabien; Ferrary, Evelyne; Cotin, Stéphane; Sterkers, Olivier; Duriez, Christian

2014-01-01

Otological microsurgery is delicate and requires high dexterity in bad ergonomic conditions. To assist surgeons in these indications, a teleoperated system, called RobOtol, is developed. This robot enhances gesture accuracy and handiness and allows exploration of new procedures for middle ear surgery. To plan new procedures that exploit the capacities given by the robot, a surgical simulator is developed. The simulation reproduces with high fidelity the behavior of the anatomical structures and can also be used as a training tool for an easier control of the robot for surgeons. In the paper, we introduce the middle ear surgical simulation and then we perform virtually two challenging procedures with the robot. We show how interactive simulation can assist in analyzing the benefits of robotics in the case of complex manipulations or ergonomics studies and allow the development of innovative surgical procedures. New robot-based microsurgical procedures are investigated. The improvement offered by RobOtol is also evaluated and discussed.

Middle-Ear Microsurgery Simulation to Improve New Robotic Procedures

PubMed Central

Kazmitcheff, Guillaume; Nguyen, Yann; Miroir, Mathieu; Péan, Fabien; Ferrary, Evelyne; Cotin, Stéphane; Sterkers, Olivier; Duriez, Christian

2014-01-01

Otological microsurgery is delicate and requires high dexterity in bad ergonomic conditions. To assist surgeons in these indications, a teleoperated system, called RobOtol, is developed. This robot enhances gesture accuracy and handiness and allows exploration of new procedures for middle ear surgery. To plan new procedures that exploit the capacities given by the robot, a surgical simulator is developed. The simulation reproduces with high fidelity the behavior of the anatomical structures and can also be used as a training tool for an easier control of the robot for surgeons. In the paper, we introduce the middle ear surgical simulation and then we perform virtually two challenging procedures with the robot. We show how interactive simulation can assist in analyzing the benefits of robotics in the case of complex manipulations or ergonomics studies and allow the development of innovative surgical procedures. New robot-based microsurgical procedures are investigated. The improvement offered by RobOtol is also evaluated and discussed. PMID:25157373

Applications of fidelity measures to complex quantum systems

PubMed Central

2016-01-01

We revisit fidelity as a measure for the stability and the complexity of the quantum motion of single-and many-body systems. Within the context of cold atoms, we present an overview of applications of two fidelities, which we call static and dynamical fidelity, respectively. The static fidelity applies to quantum problems which can be diagonalized since it is defined via the eigenfunctions. In particular, we show that the static fidelity is a highly effective practical detector of avoided crossings characterizing the complexity of the systems and their evolutions. The dynamical fidelity is defined via the time-dependent wave functions. Focusing on the quantum kicked rotor system, we highlight a few practical applications of fidelity measurements in order to better understand the large variety of dynamical regimes of this paradigm of a low-dimensional system with mixed regular–chaotic phase space. PMID:27140967

Generation of high-fidelity four-photon cluster state and quantum-domain demonstration of one-way quantum computing.

PubMed

Tokunaga, Yuuki; Kuwashiro, Shin; Yamamoto, Takashi; Koashi, Masato; Imoto, Nobuyuki

2008-05-30

We experimentally demonstrate a simple scheme for generating a four-photon entangled cluster state with fidelity over 0.860+/-0.015. We show that the fidelity is high enough to guarantee that the produced state is distinguished from Greenberger-Horne-Zeilinger, W, and Dicke types of genuine four-qubit entanglement. We also demonstrate basic operations of one-way quantum computing using the produced state and show that the output state fidelities surpass classical bounds, which indicates that the entanglement in the produced state essentially contributes to the quantum operation.

The Persistent Issue of Simulator Sickness in Naval Aviation Training.

PubMed

Geyer, Daniel J; Biggs, Adam T

2018-04-01

Virtual simulations offer nearly unlimited training potential for naval aviation due to the wide array of scenarios that can be simulated in a safe, reliable, and cost-effective environment. This versatility has created substantial interest in using existing and emerging virtual technology to enhance training scenarios. However, the virtual simulations themselves may hinder training initiatives by inducing simulator sickness among the trainees, which is a series of symptoms similar to motion sickness that can arise from simulator use. Simulator sickness has been a problem for military aviation since the first simulators were introduced. The problem has also persisted despite the increasing fidelity and sense of immersion offered by new generations of simulators. As such, it is essential to understand the various problems so that trainers can ensure the best possible use of the simulators. This review will examine simulator sickness as it pertains to naval aviation training. Topics include: the prevailing theories on why symptoms develop, methods of measurement, contributing factors, effects on training, effects when used shipboard, aftereffects, countermeasures, and recommendations for future research involving virtual simulations in an aviation training environment.Geyer DJ, Biggs AT. The persistent issue of simulator sickness in naval aviation training. Aerosp Med Hum Perform. 2018; 89(4):396-405.

VERSE - Virtual Equivalent Real-time Simulation

NASA Technical Reports Server (NTRS)

Zheng, Yang; Martin, Bryan J.; Villaume, Nathaniel

2005-01-01

Distributed real-time simulations provide important timing validation and hardware in the- loop results for the spacecraft flight software development cycle. Occasionally, the need for higher fidelity modeling and more comprehensive debugging capabilities - combined with a limited amount of computational resources - calls for a non real-time simulation environment that mimics the real-time environment. By creating a non real-time environment that accommodates simulations and flight software designed for a multi-CPU real-time system, we can save development time, cut mission costs, and reduce the likelihood of errors. This paper presents such a solution: Virtual Equivalent Real-time Simulation Environment (VERSE). VERSE turns the real-time operating system RTAI (Real-time Application Interface) into an event driven simulator that runs in virtual real time. Designed to keep the original RTAI architecture as intact as possible, and therefore inheriting RTAI's many capabilities, VERSE was implemented with remarkably little change to the RTAI source code. This small footprint together with use of the same API allows users to easily run the same application in both real-time and virtual time environments. VERSE has been used to build a workstation testbed for NASA's Space Interferometry Mission (SIM PlanetQuest) instrument flight software. With its flexible simulation controls and inexpensive setup and replication costs, VERSE will become an invaluable tool in future mission development.

Panel Stiffener Debonding Analysis using a Shell/3D Modeling Technique

NASA Technical Reports Server (NTRS)

Krueger, Ronald; Ratcliffe, James G.; Minguet, Pierre J.

2008-01-01

A shear loaded, stringer reinforced composite panel is analyzed to evaluate the fidelity of computational fracture mechanics analyses of complex structures. Shear loading causes the panel to buckle. The resulting out -of-plane deformations initiate skin/stringer separation at the location of an embedded defect. The panel and surrounding load fixture were modeled with shell elements. A small section of the stringer foot, web and noodle as well as the panel skin near the delamination front were modeled with a local 3D solid model. Across the width of the stringer fo to, the mixed-mode strain energy release rates were calculated using the virtual crack closure technique. A failure index was calculated by correlating the results with a mixed-mode failure criterion of the graphite/epoxy material. The objective was to study the effect of the fidelity of the local 3D finite element model on the computed mixed-mode strain energy release rates and the failure index.

Panel-Stiffener Debonding and Analysis Using a Shell/3D Modeling Technique

NASA Technical Reports Server (NTRS)

Krueger, Ronald; Ratcliffe, James G.; Minguet, Pierre J.

2007-01-01

A shear loaded, stringer reinforced composite panel is analyzed to evaluate the fidelity of computational fracture mechanics analyses of complex structures. Shear loading causes the panel to buckle. The resulting out-of-plane deformations initiate skin/stringer separation at the location of an embedded defect. The panel and surrounding load fixture were modeled with shell elements. A small section of the stringer foot, web and noodle as well as the panel skin near the delamination front were modeled with a local 3D solid model. Across the width of the stringer foot, the mixed-mode strain energy release rates were calculated using the virtual crack closure technique. A failure index was calculated by correlating the results with a mixed-mode failure criterion of the graphite/epoxy material. The objective was to study the effect of the fidelity of the local 3D finite element model on the computed mixed-mode strain energy release rates and the failure index.

Implementation of a Text-Based Content Intervention in Secondary Social Studies Classes.

PubMed

Wanzek, Jeanne; Vaughn, Sharon

2016-12-01

We describe teacher fidelity (adherence to the components of the treatment as specified by the research team) based on a series of studies of a multicomponent intervention, Promoting Acceleration of Comprehension and Content Through Text (PACT), with middle and high school social studies teachers and their students. Findings reveal that even with highly specified materials and implementing practices that are aligned with effective reading comprehension and content instruction, teachers' fidelity was consistently low for some components and high for others. Teachers demonstrated consistently high implementation fidelity and quality for the instructional components of building background knowledge (comprehension canopy) and teaching key content vocabulary (essential words), whereas we recorded consistently lower fidelity and quality of implementation for the instructional components of critical reading and knowledge application. © 2016 Wiley Periodicals, Inc.

A comparison of select image-compression algorithms for an electronic still camera

NASA Technical Reports Server (NTRS)

Nerheim, Rosalee

1989-01-01

This effort is a study of image-compression algorithms for an electronic still camera. An electronic still camera can record and transmit high-quality images without the use of film, because images are stored digitally in computer memory. However, high-resolution images contain an enormous amount of information, and will strain the camera's data-storage system. Image compression will allow more images to be stored in the camera's memory. For the electronic still camera, a compression algorithm that produces a reconstructed image of high fidelity is most important. Efficiency of the algorithm is the second priority. High fidelity and efficiency are more important than a high compression ratio. Several algorithms were chosen for this study and judged on fidelity, efficiency and compression ratio. The transform method appears to be the best choice. At present, the method is compressing images to a ratio of 5.3:1 and producing high-fidelity reconstructed images.

Design, development, and evaluation of an online virtual emergency department for training trauma teams.

PubMed

Youngblood, Patricia; Harter, Phillip M; Srivastava, Sakti; Moffett, Shannon; Heinrichs, Wm LeRoy; Dev, Parvati

2008-01-01

Training interdisciplinary trauma teams to work effectively together using simulation technology has led to a reduction in medical errors in emergency department, operating room, and delivery room contexts. High-fidelity patient simulators (PSs)-the predominant method for training healthcare teams-are expensive to develop and implement and require that trainees be present in the same place at the same time. In contrast, online computer-based simulators are more cost effective and allow simultaneous participation by students in different locations and time zones. In this pilot study, the researchers created an online virtual emergency department (Virtual ED) for team training in crisis management, and compared the effectiveness of the Virtual ED with the PS. We hypothesized that there would be no difference in learning outcomes for graduating medical students trained with each method. In this pilot study, we used a pretest-posttest control group, experimental design in which 30 subjects were randomly assigned to either the Virtual ED or the PS system. In the Virtual ED each subject logged into the online environment and took the role of a team member. Four-person teams worked together in the Virtual ED, communicating in real time with live voice over Internet protocol, to manage computer-controlled patients who exhibited signs and symptoms of physical trauma. Each subject had the opportunity to be the team leader. The subjects' leadership behavior as demonstrated in both a pretest case and a posttest case was assessed by 3 raters, using a behaviorally anchored scale. In the PS environment, 4-person teams followed the same research protocol, using the same clinical scenarios in a Simulation Center. Guided by the Emergency Medicine Crisis Resource Management curriculum, both the Virtual ED and the PS groups applied the basic principles of team leadership and trauma management (Advanced Trauma Life Support) to manage 6 trauma cases-a pretest case, 4 training cases, and a posttest case. The subjects in each group were assessed individually with the same simulation method that they used for the training cases. Subjects who used either the Virtual ED or the PS showed significant improvement in performance between pretest and posttest cases (P < 0.05). In addition, there was no significant difference in subjects' performance between the 2 types of simulation, suggesting that the online Virtual ED may be as effective for learning team skills as the PS, the method widely used in Simulation Centers. Data on usability and attitudes toward both simulation methods as learning tools were equally positive. This study shows the potential value of using virtual learning environments for developing medical students' and resident physicians' team leadership and crisis management skills.

Effects of introducing a voluntary virtual patient module to a basic life support with an automated external defibrillator course: a randomised trial

PubMed Central

2012-01-01

Background The concept of virtual patients (VPs) encompasses a great variety of predominantly case-based e-learning modules with different complexity and fidelity levels. Methods for effective placement of VPs in the process of medical education are sought. The aim of this study was to determine whether the introduction of a voluntary virtual patients module into a basic life support with an automated external defibrillator (BLS-AED) course improved the knowledge and skills of students taking the course. Methods Half of the students were randomly assigned to an experimental group and given voluntary access to a virtual patient module consisting of six cases presenting BLS-AED knowledge and skills. Pre- and post-course knowledge tests and skills assessments were performed, as well as a survey of students' satisfaction with the VP usage. In addition, time spent using the virtual patient system, percentage of screen cards viewed and scores in the formative questions in the VP system throughout the course were traced and recorded. Results The study was conducted over a six week period and involved 226 first year medical students. The voluntary module was used by 61 (54%) of the 114 entitled study participants. The group that used VPs demonstrated better results in knowledge acquisition and in some key BLS-AED action skills than the group without access, or those students from the experimental group deliberately not using virtual patients. Most of the students rated the combination of VPs and corresponding teaching events positively. Conclusions The overall positive reaction of students and encouraging results in knowledge and skills acquisition suggest that the usage of virtual patients in a BLS-AED course on a voluntary basis is feasible and should be further investigated. PMID:22709278

Effects of introducing a voluntary virtual patient module to a basic life support with an automated external defibrillator course: a randomised trial.

PubMed

Kononowicz, Andrzej A; Krawczyk, Paweł; Cebula, Grzegorz; Dembkowska, Marta; Drab, Edyta; Frączek, Bartosz; Stachoń, Aleksandra J; Andres, Janusz

2012-06-18

The concept of virtual patients (VPs) encompasses a great variety of predominantly case-based e-learning modules with different complexity and fidelity levels. Methods for effective placement of VPs in the process of medical education are sought. The aim of this study was to determine whether the introduction of a voluntary virtual patients module into a basic life support with an automated external defibrillator (BLS-AED) course improved the knowledge and skills of students taking the course. Half of the students were randomly assigned to an experimental group and given voluntary access to a virtual patient module consisting of six cases presenting BLS-AED knowledge and skills. Pre- and post-course knowledge tests and skills assessments were performed, as well as a survey of students' satisfaction with the VP usage. In addition, time spent using the virtual patient system, percentage of screen cards viewed and scores in the formative questions in the VP system throughout the course were traced and recorded. The study was conducted over a six week period and involved 226 first year medical students. The voluntary module was used by 61 (54%) of the 114 entitled study participants. The group that used VPs demonstrated better results in knowledge acquisition and in some key BLS-AED action skills than the group without access, or those students from the experimental group deliberately not using virtual patients. Most of the students rated the combination of VPs and corresponding teaching events positively. The overall positive reaction of students and encouraging results in knowledge and skills acquisition suggest that the usage of virtual patients in a BLS-AED course on a voluntary basis is feasible and should be further investigated.

OR fire virtual training simulator: design and face validity.

PubMed

Dorozhkin, Denis; Olasky, Jaisa; Jones, Daniel B; Schwaitzberg, Steven D; Jones, Stephanie B; Cao, Caroline G L; Molina, Marcos; Henriques, Steven; Wang, Jinling; Flinn, Jeff; De, Suvranu

2017-09-01

The Virtual Electrosurgical Skill Trainer is a tool for training surgeons the safe operation of electrosurgery tools in both open and minimally invasive surgery. This training includes a dedicated team-training module that focuses on operating room (OR) fire prevention and response. The module was developed to allow trainees, practicing surgeons, anesthesiologist, and nurses to interact with a virtual OR environment, which includes anesthesia apparatus, electrosurgical equipment, a virtual patient, and a fire extinguisher. Wearing a head-mounted display, participants must correctly identify the "fire triangle" elements and then successfully contain an OR fire. Within these virtual reality scenarios, trainees learn to react appropriately to the simulated emergency. A study targeted at establishing the face validity of the virtual OR fire simulator was undertaken at the 2015 Society of American Gastrointestinal and Endoscopic Surgeons conference. Forty-nine subjects with varying experience participated in this Institutional Review Board-approved study. The subjects were asked to complete the OR fire training/prevention sequence in the VEST simulator. Subjects were then asked to answer a subjective preference questionnaire consisting of sixteen questions, focused on the usefulness and fidelity of the simulator. On a 5-point scale, 12 of 13 questions were rated at a mean of 3 or greater (92%). Five questions were rated above 4 (38%), particularly those focusing on the simulator effectiveness and its usefulness in OR fire safety training. A total of 33 of the 49 participants (67%) chose the virtual OR fire trainer over the traditional training methods such as a textbook or an animal model. Training for OR fire emergencies in fully immersive VR environments, such as the VEST trainer, may be the ideal training modality. The face validity of the OR fire training module of the VEST simulator was successfully established on many aspects of the simulation.

Stimulated Brillouin scattering continuous wave phase conjugation in step-index fiber optics.

PubMed

Massey, Steven M; Spring, Justin B; Russell, Timothy H

2008-07-21

Continuous wave (CW) stimulated Brillouin scattering (SBS) phase conjugation in step-index optical fibers was studied experimentally and modeled as a function of fiber length. A phase conjugate fidelity over 80% was measured from SBS in a 40 m fiber using a pinhole technique. Fidelity decreases with fiber length, and a fiber with a numerical aperture (NA) of 0.06 was found to generate good phase conjugation fidelity over longer lengths than a fiber with 0.13 NA. Modeling and experiment support previous work showing the maximum interaction length which yields a high fidelity phase conjugate beam is inversely proportional to the fiber NA(2), but find that fidelity remains high over much longer fiber lengths than previous models calculated. Conditions for SBS beam cleanup in step-index fibers are discussed.

Phosphate-binding pocket in Dicer-2 PAZ domain for high-fidelity siRNA production

PubMed Central

Kandasamy, Suresh K.

2016-01-01

The enzyme Dicer produces small silencing RNAs such as micro-RNAs (miRNAs) and small interfering RNAs (siRNAs). In Drosophila, Dicer-1 produces ∼22–24-nt miRNAs from pre-miRNAs, whereas Dicer-2 makes 21-nt siRNAs from long double-stranded RNAs (dsRNAs). How Dicer-2 precisely makes 21-nt siRNAs with a remarkably high fidelity is unknown. Here we report that recognition of the 5′-monophosphate of a long dsRNA substrate by a phosphate-binding pocket in the Dicer-2 PAZ (Piwi, Argonaute, and Zwille/Pinhead) domain is crucial for the length fidelity, but not the efficiency, in 21-nt siRNA production. Loss of the length fidelity, meaning increased length heterogeneity of siRNAs, caused by point mutations in the phosphate-binding pocket of the Dicer-2 PAZ domain decreased RNA silencing activity in vivo, showing the importance of the high fidelity to make 21-nt siRNAs. We propose that the 5′-monophosphate of a long dsRNA substrate is anchored by the phosphate-binding pocket in the Dicer-2 PAZ domain and the distance between the pocket and the RNA cleavage active site in the RNaseIII domain corresponds to the 21-nt pitch in the A-form duplex of a long dsRNA substrate, resulting in high-fidelity 21-nt siRNA production. This study sheds light on the molecular mechanism by which Dicer-2 produces 21-nt siRNAs with a remarkably high fidelity for efficient RNA silencing. PMID:27872309

Undulating fins produce off-axis thrust and flow structures.

PubMed

Neveln, Izaak D; Bale, Rahul; Bhalla, Amneet Pal Singh; Curet, Oscar M; Patankar, Neelesh A; MacIver, Malcolm A

2014-01-15

While wake structures of many forms of swimming and flying are well characterized, the wake generated by a freely swimming undulating fin has not yet been analyzed. These elongated fins allow fish to achieve enhanced agility exemplified by the forward, backward and vertical swimming capabilities of knifefish, and also have potential applications in the design of more maneuverable underwater vehicles. We present the flow structure of an undulating robotic fin model using particle image velocimetry to measure fluid velocity fields in the wake. We supplement the experimental robotic work with high-fidelity computational fluid dynamics, simulating the hydrodynamics of both a virtual fish, whose fin kinematics and fin plus body morphology are measured from a freely swimming knifefish, and a virtual rendering of our robot. Our results indicate that a series of linked vortex tubes is shed off the long edge of the fin as the undulatory wave travels lengthwise along the fin. A jet at an oblique angle to the fin is associated with the successive vortex tubes, propelling the fish forward. The vortex structure bears similarity to the linked vortex ring structure trailing the oscillating caudal fin of a carangiform swimmer, though the vortex rings are distorted because of the undulatory kinematics of the elongated fin.

Design of a cost-effective, hemodynamically adjustable model for resuscitative endovascular balloon occlusion of the aorta (REBOA) simulation.

PubMed

Keller, Benjamin A; Salcedo, Edgardo S; Williams, Timothy K; Neff, Lucas P; Carden, Anthony J; Li, Yiran; Gotlib, Oren; Tran, Nam K; Galante, Joseph M

2016-09-01

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an adjunct technique for salvaging patients with noncompressible torso hemorrhage. Current REBOA training paradigms require large animals, virtual reality simulators, or human cadavers for acquisition of skills. These training strategies are expensive and resource intensive, which may prevent widespread dissemination of REBOA. We have developed a low-cost, near-physiologic, pulsatile REBOA simulator by connecting an anatomic vascular circuit constructed out of latex and polyvinyl chloride tubing to a commercially available pump. This pulsatile simulator is capable of generating cardiac outputs ranging from 1.7 to 6.8 L/min with corresponding arterial blood pressures of 54 to 226/14 to 121 mmHg. The simulator accommodates a 12 French introducer sheath and a CODA balloon catheter. Upon balloon inflation, the arterial waveform distal to the occlusion flattens, distal pulsation within the simulator is lost, and systolic blood pressures proximal to the balloon catheter increase by up to 62 mmHg. Further development and validation of this simulator will allow for refinement, reduction, and replacement of large animal models, costly virtual reality simulators, and perfused cadavers for training purposes. This will ultimately facilitate the low-cost, high-fidelity REBOA simulation needed for the widespread dissemination of this life-saving technique.

Teaching Elliptical Excision Skills to Novice Medical Students: A Randomized Controlled Study Comparing Low- and High-Fidelity Bench Models

PubMed Central

Denadai, Rafael; Oshiiwa, Marie; Saad-Hossne, Rogério

2014-01-01

Background: The search for alternative and effective forms of training simulation is needed due to ethical and medico-legal aspects involved in training surgical skills on living patients, human cadavers and living animals. Aims: To evaluate if the bench model fidelity interferes in the acquisition of elliptical excision skills by novice medical students. Materials and Methods: Forty novice medical students were randomly assigned to 5 practice conditions with instructor-directed elliptical excision skills’ training (n = 8): didactic materials (control); organic bench model (low-fidelity); ethylene-vinyl acetate bench model (low-fidelity); chicken legs’ skin bench model (high-fidelity); or pig foot skin bench model (high-fidelity). Pre- and post-tests were applied. Global rating scale, effect size, and self-perceived confidence based on Likert scale were used to evaluate all elliptical excision performances. Results: The analysis showed that after training, the students practicing on bench models had better performance based on Global rating scale (all P < 0.0000) and felt more confident to perform elliptical excision skills (all P < 0.0000) when compared to the control. There was no significant difference (all P > 0.05) between the groups that trained on bench models. The magnitude of the effect (basic cutaneous surgery skills’ training) was considered large (>0.80) in all measurements. Conclusion: The acquisition of elliptical excision skills after instructor-directed training on low-fidelity bench models was similar to the training on high-fidelity bench models; and there was a more substantial increase in elliptical excision performances of students that trained on all simulators compared to the learning on didactic materials. PMID:24700937

Use of High Fidelity Methods in Multidisciplinary Optimization-A Preliminary Survey

NASA Technical Reports Server (NTRS)

Guruswamy, Guru P.; Kwak, Dochan (Technical Monitor)

2002-01-01

Multidisciplinary optimization is a key element of design process. To date multidiscipline optimization methods that use low fidelity methods are well advanced. Optimization methods based on simple linear aerodynamic equations and plate structural equations have been applied to complex aerospace configurations. However, use of high fidelity methods such as the Euler/ Navier-Stokes for fluids and 3-D (three dimensional) finite elements for structures has begun recently. As an activity of Multidiscipline Design Optimization Technical Committee (MDO TC) of AIAA (American Institute of Aeronautics and Astronautics), an effort was initiated to assess the status of the use of high fidelity methods in multidisciplinary optimization. Contributions were solicited through the members MDO TC committee. This paper provides a summary of that survey.

Emergent Capabilities Converging into M and S 2.0

NASA Technical Reports Server (NTRS)

Reitz, Emilie; Reist, Jay

2012-01-01

The continued operational environment complexity faced by the Department of Defense, despite a restricted resource environment, is a mandate for greater adaptability and availability in joint training. To address these constraints, this paper proposes a model for the potential integration of adaptability training, virtual world capabilities and immersive training into the wider Joint Live Virtual and Constructive (JLVC) Federation, supported by human, social, cultural and behavior modeling, and measurement and assessment. By fusing those capabilities and modeling and simulation enhancements into the JLVC federation, it will create a force who is more apt to arrive at and implement correct decisions, and more able to appropriately seize initiative in the field. The model would allow for the testing and training of capabilities and TTPs that cannot be reasonably explored to their logical conclusions in a 'live' environment, as well as enhance training fidelity for all echelons and tasks.

ViDI: Virtual Diagnostics Interface. Volume 1; The Future of Wind Tunnel Testing

NASA Technical Reports Server (NTRS)

Fleming, Gary A. (Technical Monitor); Schwartz, Richard J.

2004-01-01

The quality of data acquired in a given test facility ultimately resides within the fidelity and implementation of the instrumentation systems. Over the last decade, the emergence of robust optical techniques has vastly expanded the envelope of measurement possibilities. At the same time the capabilities for data processing, data archiving and data visualization required to extract the highest level of knowledge from these global, on and off body measurement techniques have equally expanded. Yet today, while the instrumentation has matured to the production stage, an optimized solution for gaining knowledge from the gigabytes of data acquired per test (or even per test point) is lacking. A technological void has to be filled in order to possess a mechanism for near-real time knowledge extraction during wind tunnel experiments. Under these auspices, the Virtual Diagnostics Interface, or ViDI, was developed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zitney, S.E.

This presentation will examine process systems engineering R&D needs for application to advanced fossil energy (FE) systems and highlight ongoing research activities at the National Energy Technology Laboratory (NETL) under the auspices of a recently launched Collaboratory for Process & Dynamic Systems Research. The three current technology focus areas include: 1) High-fidelity systems with NETL's award-winning Advanced Process Engineering Co-Simulator (APECS) technology for integrating process simulation with computational fluid dynamics (CFD) and virtual engineering concepts, 2) Dynamic systems with R&D on plant-wide IGCC dynamic simulation, control, and real-time training applications, and 3) Systems optimization including large-scale process optimization, stochastic simulationmore » for risk/uncertainty analysis, and cost estimation. Continued R&D aimed at these and other key process systems engineering models, methods, and tools will accelerate the development of advanced gasification-based FE systems and produce increasingly valuable outcomes for DOE and the Nation.« less

Secure Large-Scale Airport Simulations Using Distributed Computational Resources

NASA Technical Reports Server (NTRS)

McDermott, William J.; Maluf, David A.; Gawdiak, Yuri; Tran, Peter; Clancy, Dan (Technical Monitor)

2001-01-01

To fully conduct research that will support the far-term concepts, technologies and methods required to improve the safety of Air Transportation a simulation environment of the requisite degree of fidelity must first be in place. The Virtual National Airspace Simulation (VNAS) will provide the underlying infrastructure necessary for such a simulation system. Aerospace-specific knowledge management services such as intelligent data-integration middleware will support the management of information associated with this complex and critically important operational environment. This simulation environment, in conjunction with a distributed network of supercomputers, and high-speed network connections to aircraft, and to Federal Aviation Administration (FAA), airline and other data-sources will provide the capability to continuously monitor and measure operational performance against expected performance. The VNAS will also provide the tools to use this performance baseline to obtain a perspective of what is happening today and of the potential impact of proposed changes before they are introduced into the system.

Three-dimensional temporomandibular joint modeling and animation.

PubMed

Cascone, Piero; Rinaldi, Fabrizio; Pagnoni, Mario; Marianetti, Tito Matteo; Tedaldi, Massimiliano

2008-11-01

The three-dimensional (3D) temporomandibular joint (TMJ) model derives from a study of the cranium by 3D virtual reality and mandibular function animation. The starting point of the project is high-fidelity digital acquisition of a human dry skull. The cooperation between the maxillofacial surgeon and the cartoonist enables the reconstruction of the fibroconnective components of the TMJ that are the keystone for comprehension of the anatomic and functional features of the mandible. The skeletal model is customized with the apposition of the temporomandibular ligament, the articular disk, the retrodiskal tissue, and the medial and the lateral ligament of the disk. The simulation of TMJ movement is the result of the integration of up-to-date data on the biomechanical restrictions. The 3D TMJ model is an easy-to-use application that may be run on a personal computer for the study of the TMJ and its biomechanics.

Co-located haptic and 3D graphic interface for medical simulations.

PubMed

Berkelman, Peter; Miyasaka, Muneaki; Bozlee, Sebastian

2013-01-01

We describe a system which provides high-fidelity haptic feedback in the same physical location as a 3D graphical display, in order to enable realistic physical interaction with virtual anatomical tissue during modelled procedures such as needle driving, palpation, and other interventions performed using handheld instruments. The haptic feedback is produced by the interaction between an array of coils located behind a thin flat LCD screen, and permanent magnets embedded in the instrument held by the user. The coil and magnet configuration permits arbitrary forces and torques to be generated on the instrument in real time according to the dynamics of the simulated tissue by activating the coils in combination. A rigid-body motion tracker provides position and orientation feedback of the handheld instrument to the computer simulation, and the 3D display is produced using LCD shutter glasses and a head-tracking system for the user.

Building Airport Surface HITL Simulation Capability

NASA Technical Reports Server (NTRS)

Chinn, Fay Cherie

2016-01-01

FutureFlight Central is a high fidelity, real-time simulator designed to study surface operations and automation. As an air traffic control tower simulator, FFC allows stakeholders such as the FAA, controllers, pilots, airports, and airlines to develop and test advanced surface and terminal area concepts and automation including NextGen and beyond automation concepts and tools. These technologies will improve the safety, capacity and environmental issues facing the National Airspace system. FFC also has extensive video streaming capabilities, which combined with the 3-D database capability makes the facility ideal for any research needing an immersive virtual and or video environment. FutureFlight Central allows human in the loop testing which accommodates human interactions and errors giving a more complete picture than fast time simulations. This presentation describes FFCs capabilities and the components necessary to build an airport surface human in the loop simulation capability.

Measuring trainer fidelity in the transfer of suicide prevention training

PubMed Central

Cross, Wendi F.; Pisani, Anthony R.; Schmeelk-Cone, Karen; Xia, Yinglin; Tu, Xin; McMahon, Marcie; Munfakh, Jimmie Lou; Gould, Madelyn S.

2014-01-01

Background Finding effective and efficient models to train large numbers of suicide prevention interventionists, including ‘hotline’ crisis counselors, is a high priority. Train-the-trainer (TTT) models are widely used but understudied. Aims To assess the extent to which trainers following TTT delivered the Applied Suicide Intervention Skills Training (ASIST) program with fidelity, and to examine fidelity across two trainings and seven training segments. Methods We recorded and reliably rated trainer fidelity, defined as adherence to program content and competence of program delivery, for 34 newly trained ASIST trainers delivering the program to crisis center staff on two separate occasions. A total of 324 observations were coded. Trainer demographics were also collected. Results On average, trainers delivered two-thirds of the program. Previous training was associated with lower levels of trainer adherence to the program. 18% of trainers' observations were rated as solidly competent. Trainers did not improve fidelity from their first to second training. Significantly higher fidelity was found for lectures and lower fidelity was found for interactive training activities including asking about suicide and creating a safe plan. Conclusions We found wide variability in trainer fidelity to the ASIST program following TTT and few trainers had high levels of both adherence and competence. More research is needed to examine the cost-effectiveness of TTT models. PMID:24901061

Blend Shape Interpolation and FACS for Realistic Avatar

NASA Astrophysics Data System (ADS)

Alkawaz, Mohammed Hazim; Mohamad, Dzulkifli; Basori, Ahmad Hoirul; Saba, Tanzila

2015-03-01

The quest of developing realistic facial animation is ever-growing. The emergence of sophisticated algorithms, new graphical user interfaces, laser scans and advanced 3D tools imparted further impetus towards the rapid advancement of complex virtual human facial model. Face-to-face communication being the most natural way of human interaction, the facial animation systems became more attractive in the information technology era for sundry applications. The production of computer-animated movies using synthetic actors are still challenging issues. Proposed facial expression carries the signature of happiness, sadness, angry or cheerful, etc. The mood of a particular person in the midst of a large group can immediately be identified via very subtle changes in facial expressions. Facial expressions being very complex as well as important nonverbal communication channel are tricky to synthesize realistically using computer graphics. Computer synthesis of practical facial expressions must deal with the geometric representation of the human face and the control of the facial animation. We developed a new approach by integrating blend shape interpolation (BSI) and facial action coding system (FACS) to create a realistic and expressive computer facial animation design. The BSI is used to generate the natural face while the FACS is employed to reflect the exact facial muscle movements for four basic natural emotional expressions such as angry, happy, sad and fear with high fidelity. The results in perceiving the realistic facial expression for virtual human emotions based on facial skin color and texture may contribute towards the development of virtual reality and game environment of computer aided graphics animation systems.

Virtual Reality Simulation for the Operating Room

PubMed Central

Gallagher, Anthony G.; Ritter, E Matt; Champion, Howard; Higgins, Gerald; Fried, Marvin P.; Moses, Gerald; Smith, C Daniel; Satava, Richard M.

2005-01-01

Summary Background Data: To inform surgeons about the practical issues to be considered for successful integration of virtual reality simulation into a surgical training program. The learning and practice of minimally invasive surgery (MIS) makes unique demands on surgical training programs. A decade ago Satava proposed virtual reality (VR) surgical simulation as a solution for this problem. Only recently have robust scientific studies supported that vision Methods: A review of the surgical education, human-factor, and psychology literature to identify important factors which will impinge on the successful integration of VR training into a surgical training program. Results: VR is more likely to be successful if it is systematically integrated into a well-thought-out education and training program which objectively assesses technical skills improvement proximate to the learning experience. Validated performance metrics should be relevant to the surgical task being trained but in general will require trainees to reach an objectively determined proficiency criterion, based on tightly defined metrics and perform at this level consistently. VR training is more likely to be successful if the training schedule takes place on an interval basis rather than massed into a short period of extensive practice. High-fidelity VR simulations will confer the greatest skills transfer to the in vivo surgical situation, but less expensive VR trainers will also lead to considerably improved skills generalizations. Conclusions: VR for improved performance of MIS is now a reality. However, VR is only a training tool that must be thoughtfully introduced into a surgical training curriculum for it to successfully improve surgical technical skills. PMID:15650649

Preschool children's development in classic Montessori, supplemented Montessori, and conventional programs.

PubMed

Lillard, Angeline S

2012-06-01

Research on the outcomes of Montessori education is scarce and results are inconsistent. One possible reason for the inconsistency is variations in Montessori implementation fidelity. To test whether outcomes vary according to implementation fidelity, we examined preschool children enrolled in high fidelity classic Montessori programs, lower fidelity Montessori programs that supplemented the program with conventional school activities, and, for comparison, conventional programs. Children were tested at the start and end of the school year on a range of social and academic skills. Although they performed no better in the fall, children in Classic Montessori programs, as compared with children in Supplemented Montessori and Conventional programs, showed significantly greater school-year gains on outcome measures of executive function, reading, math, vocabulary, and social problem-solving, suggesting that high fidelity Montessori implementation is associated with better outcomes than lower fidelity Montessori programs or conventional programs. Copyright © 2012 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

An Investigation of the Impact of Aerodynamic Model Fidelity on Close-In Combat Effectiveness Prediction in Piloted Simulation

NASA Technical Reports Server (NTRS)

Persing, T. Ray; Bellish, Christine A.; Brandon, Jay; Kenney, P. Sean; Carzoo, Susan; Buttrill, Catherine; Guenther, Arlene

2005-01-01

Several aircraft airframe modeling approaches are currently being used in the DoD community for acquisition, threat evaluation, training, and other purposes. To date there has been no clear empirical study of the impact of airframe simulation fidelity on piloted real-time aircraft simulation study results, or when use of a particular level of fidelity is indicated. This paper documents a series of piloted simulation studies using three different levels of airframe model fidelity. This study was conducted using the NASA Langley Differential Maneuvering Simulator. Evaluations were conducted with three pilots for scenarios requiring extensive maneuvering of the airplanes during air combat. In many cases, a low-fidelity modified point-mass model may be sufficient to evaluate the combat effectiveness of the aircraft. However, in cases where high angle-of-attack flying qualities and aerodynamic performance are a factor or when precision tracking ability of the aircraft must be represented, use of high-fidelity models is indicated.

Comparison of Performance Predictions for New Low-Thrust Trajectory Tools

NASA Technical Reports Server (NTRS)

Polsgrove, Tara; Kos, Larry; Hopkins, Randall; Crane, Tracie

2006-01-01

Several low thrust trajectory optimization tools have been developed over the last 3% years by the Low Thrust Trajectory Tools development team. This toolset includes both low-medium fidelity and high fidelity tools which allow the analyst to quickly research a wide mission trade space and perform advanced mission design. These tools were tested using a set of reference trajectories that exercised each tool s unique capabilities. This paper compares the performance predictions of the various tools against several of the reference trajectories. The intent is to verify agreement between the high fidelity tools and to quantify the performance prediction differences between tools of different fidelity levels.

Geomagnetic field intensity determination from Pleistocene trachytic lava flows in Jeju Geopark

NASA Astrophysics Data System (ADS)

Jeong, Doohee; Yu, Yongjae; Liu, Qingsong; Jiang, Zhaoxia; Koh, Gi Won; Koh, Dong-Chan

2014-03-01

A composite of 28 trachytic lava flows were recovered from the Jeju Geopark Drilling Project (JGDP) in Jeju Geopark, one of the new seven wonders of Nature declared by UNESCO in 2011. Each trachytic lava flow has a tendency to increase in magnetic grain size from the rapidly cooled brecciated margin and vesicle streaked zone downward into the massive crystalline flow interiors. The brecciated margin and vesicle streaked zone of individual trachytic lava flow contains exclusively fine-grained magnetite as inclusions in plagioclase. High-fidelity paleointensity determinations were obtained from 26 (out of 224 examined) samples from JGDP cores. Temporal variation of virtual axial dipole moments (VADMs) calculated from the absolute paleointensity estimates follows the trend of sint-800 data for the interval from ˜80 to ˜360 ka. High VADM from flow 21 possibly represents real intensity peak, as previously recognized high VADM in Japan at ˜336 ka, in Trans-Mexican volcanism ˜339, and in Hawaii ˜340-350 ka. Perhaps such a strong magnetic intensity near ˜325-350 ka might be smoothed out in relative paleointensity records.

A Transfer of Training Study of Control Loader Dynamics

NASA Technical Reports Server (NTRS)

Cardullo, Frank M.; Stanco, Anthony A.; Kelly, Lon C.; Houck, Jacob A.; Grube, Richard C.

2011-01-01

The control inceptor used in a simulated vehicle is an important part in maintaining the fidelity of a simulation. The force feedback provided by the control inceptor gives the operator important cues to maintain adequate performance. The dynamics of a control inceptor are typically based on a second order spring mass damper system with damping, force gradient, breakout force, and natural frequency parameters. Changing these parameters can have a great effect on pilot or driver control of the vehicle. The neuromuscular system has a very important role in manipulating the control inceptor within a vehicle. Many studies by McRuer, Aponso, and Hess have dealt with modeling the neuromuscular system and quantifying the effects of a high fidelity control loader as compared to a low fidelity control loader. Humans are adaptive in nature and their control behavior changes based on different control loader dynamics. Humans will change their control behavior to maintain tracking bandwidth and minimize tracking error. This paper reports on a quasi-transfer of training experiment which was performed at the NASA Langley Research Center. The quasi transfer of training study used a high fidelity control loader and a low fidelity control loader. Subjects trained in both simulations and then were transferred to the high fidelity control loader simulation. The parameters for the high fidelity control loader were determined from the literature. The low fidelity control loader parameters were found through testing of a simple computer joystick. A disturbance compensatory task is employed. The compensatory task involves implementing a simple horizon out the window display. A disturbance consisting of a sum of sines is used. The task consists of the subject compensating for the disturbance on the roll angle of the aircraft. The vehicle dynamics are represented as 1/s and 1/s2. The subject will try to maintain level flight throughout the experiment. The subjects consist of non-pilots to remove any effects of pilot experience. First, this paper discusses the implementation of the disturbance compensation task. Second, the high and low fidelity parameters used within the experiment are presented. Finally, an explanation of results from the experiments is presented.

The effect of simulator fidelity on acquiring non-technical skills: a randomized non-inferiority trial.

PubMed

Gu, Yuqi; Witter, Tobias; Livingston, Patty; Rao, Purnima; Varshney, Terry; Kuca, Tom; Dylan Bould, M

2017-12-01

As simulator fidelity (i.e., realism) increases from low to high, the simulator more closely resembles the real environment, but it also becomes more expensive. It is generally assumed that the use of high-fidelity simulators results in better learning; however, the effect of fidelity on learning non-technical skills (NTS) is unknown. This was a non-inferiority trial comparing the efficacy of high- vs low-fidelity simulators on learning NTS. Thirty-six postgraduate medical trainees were recruited for the trial. During the pre-test phase, the trainees were randomly assigned to manage a scenario using either a high-fidelity simulator (HFS) or a low-fidelity simulator (LFS), followed by expert debriefing. All trainees then underwent a video recorded post-test scenario on a HFS, and the NTS were assessed between the two groups. The primary outcome was the overall post-test Ottawa Global Rating Scale (OGRS), while controlling for overall pre-test OGRS scores. Non-inferiority between the LFS and HFS was based on a non-inferiority margin of greater than 1. For our primary outcome, the mean (SD) post-test overall OGRS score was not significantly different between the HFS and LFS groups after controlling for pre-test overall OGRS scores [3.8 (0.9) vs 4.0 (0.9), respectively; mean difference, 0.2; 95% confidence interval, -0.4 to 0.8; P = 0.48]. For our secondary outcomes, the post-test total OGRS score was not significantly different between the HFS and LFS groups after controlling for pre-test total OGRS scores (P = 0.33). There were significant improvements in mean overall (P = 0.01) and total (P = 0.003) OGRS scores from pre-test to post-test. There were no significant associations between postgraduate year (P = 0.82) and specialty (P = 0.67) on overall OGRS performance. This study suggests that low-fidelity simulators are non-inferior to the more costly high-fidelity simulators for teaching NTS to postgraduate medical trainees.

Using mixed methods to assess fidelity of delivery and its influencing factors in a complex self-management intervention for people with osteoarthritis and low back pain.

PubMed

Toomey, Elaine; Matthews, James; Hurley, Deirdre A

2017-08-04

Despite an increasing awareness of the importance of fidelity of delivery within complex behaviour change interventions, it is often poorly assessed. This mixed methods study aimed to establish the fidelity of delivery of a complex self-management intervention and explore the reasons for these findings using a convergent/triangulation design. Feasibility trial of the Self-management of Osteoarthritis and Low back pain through Activity and Skills (SOLAS) intervention (ISRCTN49875385), delivered in primary care physiotherapy. 60 SOLAS sessions were delivered across seven sites by nine physiotherapists. Fidelity of delivery of prespecified intervention components was evaluated using (1) audio-recordings (n=60), direct observations (n=24) and self-report checklists (n=60) and (2) individual interviews with physiotherapists (n=9). Quantitatively, fidelity scores were calculated using percentage means and SD of components delivered. Associations between fidelity scores and physiotherapist variables were analysed using Spearman's correlations. Interviews were analysed using thematic analysis to explore potential reasons for fidelity scores. Integration of quantitative and qualitative data occurred at an interpretation level using triangulation. Quantitatively, fidelity scores were high for all assessment methods; with self-report (92.7%) consistently higher than direct observations (82.7%) or audio-recordings (81.7%). There was significant variation between physiotherapists' individual scores (69.8% - 100%). Both qualitative and quantitative data (from physiotherapist variables) found that physiotherapists' knowledge (Spearman's association at p=0.003) and previous experience (p=0.008) were factors that influenced their fidelity. The qualitative data also postulated participant-level (eg, individual needs) and programme-level factors (eg, resources) as additional elements that influenced fidelity. The intervention was delivered with high fidelity. This study contributes to the limited evidence regarding fidelity assessment methods within complex behaviour change interventions. The findings suggest a combination of quantitative methods is suitable for the assessment of fidelity of delivery. A mixed methods approach provided a more insightful understanding of fidelity and its influencing factors. ISRCTN49875385; Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Using mixed methods to assess fidelity of delivery and its influencing factors in a complex self-management intervention for people with osteoarthritis and low back pain

PubMed Central

Toomey, Elaine; Matthews, James; Hurley, Deirdre A

2017-01-01

Objectives and design Despite an increasing awareness of the importance of fidelity of delivery within complex behaviour change interventions, it is often poorly assessed. This mixed methods study aimed to establish the fidelity of delivery of a complex self-management intervention and explore the reasons for these findings using a convergent/triangulation design. Setting Feasibility trial of the Self-management of Osteoarthritis and Low back pain through Activity and Skills (SOLAS) intervention (ISRCTN49875385), delivered in primary care physiotherapy. Methods and outcomes 60 SOLAS sessions were delivered across seven sites by nine physiotherapists. Fidelity of delivery of prespecified intervention components was evaluated using (1) audio-recordings (n=60), direct observations (n=24) and self-report checklists (n=60) and (2) individual interviews with physiotherapists (n=9). Quantitatively, fidelity scores were calculated using percentage means and SD of components delivered. Associations between fidelity scores and physiotherapist variables were analysed using Spearman’s correlations. Interviews were analysed using thematic analysis to explore potential reasons for fidelity scores. Integration of quantitative and qualitative data occurred at an interpretation level using triangulation. Results Quantitatively, fidelity scores were high for all assessment methods; with self-report (92.7%) consistently higher than direct observations (82.7%) or audio-recordings (81.7%). There was significant variation between physiotherapists’ individual scores (69.8% - 100%). Both qualitative and quantitative data (from physiotherapist variables) found that physiotherapists’ knowledge (Spearman’s association at p=0.003) and previous experience (p=0.008) were factors that influenced their fidelity. The qualitative data also postulated participant-level (eg, individual needs) and programme-level factors (eg, resources) as additional elements that influenced fidelity. Conclusion The intervention was delivered with high fidelity. This study contributes to the limited evidence regarding fidelity assessment methods within complex behaviour change interventions. The findings suggest a combination of quantitative methods is suitable for the assessment of fidelity of delivery. A mixed methods approach provided a more insightful understanding of fidelity and its influencing factors. Trial registration number ISRCTN49875385; Pre-results. PMID:28780544

High-fidelity gates towards a scalable superconducting quantum processor

NASA Astrophysics Data System (ADS)

Chow, Jerry M.; Corcoles, Antonio D.; Gambetta, Jay M.; Rigetti, Chad; Johnson, Blake R.; Smolin, John A.; Merkel, Seth; Poletto, Stefano; Rozen, Jim; Rothwell, Mary Beth; Keefe, George A.; Ketchen, Mark B.; Steffen, Matthias

2012-02-01

We experimentally explore the implementation of high-fidelity gates on multiple superconducting qubits coupled to multiple resonators. Having demonstrated all-microwave single and two qubit gates with fidelities > 90% on multi-qubit single-resonator systems, we expand the application to qubits across two resonators and investigate qubit coupling in this circuit. The coupled qubit-resonators are building blocks towards two-dimensional lattice networks for the application of surface code quantum error correction algorithms.

The efficacy of high-fidelity simulation on psychomotor clinical performance improvement of undergraduate nursing students.

PubMed

Vincent, Mary Anne; Sheriff, Susan; Mellott, Susan

2015-02-01

High-fidelity simulation has become a growing educational modality among institutions of higher learning ever since the Institute of Medicine recommended that it be used to improve patient safety in 2000. However, there is limited research on the effect of high-fidelity simulation on psychomotor clinical performance improvement of undergraduate nursing students being evaluated by experts using reliable and valid appraisal instruments. The purpose of this integrative review and meta-analysis is to explore what researchers have established about the impact of high-fidelity simulation on improving the psychomotor clinical performance of undergraduate nursing students. Only eight of the 1120 references met inclusion criteria. A meta-analysis using Hedges' g to compute the effect size and direction of impact yielded a range of -0.26 to +3.39. A positive effect was shown in seven of eight studies; however, there were five different research designs and six unique appraisal instruments used among these studies. More research is necessary to determine if high-fidelity simulation improves psychomotor clinical performance in undergraduate nursing students. Nursing programs from multiple sites having a standardized curriculum and using the same appraisal instruments with established reliability and validity are ideal for this work.

Assessing fidelity of delivery of smoking cessation behavioural support in practice.

PubMed

Lorencatto, Fabiana; West, Robert; Christopherson, Charlotte; Michie, Susan

2013-04-04

Effectiveness of evidence-based behaviour change interventions is likely to be undermined by failure to deliver interventions as planned. Behavioural support for smoking cessation can be a highly cost-effective, life-saving intervention. However, in practice, outcomes are highly variable. Part of this may be due to variability in fidelity of intervention implementation. To date, there have been no published studies on this. The present study aimed to: evaluate a method for assessing fidelity of behavioural support; assess fidelity of delivery in two English Stop-Smoking Services; and compare the extent of fidelity according to session types, duration, individual practitioners, and component behaviour change techniques (BCTs). Treatment manuals and transcripts of 34 audio-recorded behavioural support sessions were obtained from two Stop-Smoking Services and coded into component BCTs using a taxonomy of 43 BCTs. Inter-rater reliability was assessed using percentage agreement. Fidelity was assessed by examining the proportion of BCTs specified in the manuals that were delivered in individual sessions. This was assessed by session type (i.e., pre-quit, quit, post-quit), duration, individual practitioner, and BCT. Inter-coder reliability was high (87.1%). On average, 66% of manual-specified BCTs were delivered per session (SD 15.3, range: 35% to 90%). In Service 1, average fidelity was highest for post-quit sessions (69%) and lowest for pre-quit (58%). In Service 2, fidelity was highest for quit-day (81%) and lowest for post-quit sessions (56%). Session duration was not significantly correlated with fidelity. Individual practitioner fidelity ranged from 55% to 78%. Individual manual-specified BCTs were delivered on average 63% of the time (SD 28.5, range: 0 to 100%). The extent to which smoking cessation behavioural support is delivered as specified in treatment manuals can be reliably assessed using transcripts of audiotaped sessions. This allows the investigation of the implementation of evidence-based practice in relation to smoking cessation, a first step in designing interventions to improve it. There are grounds for believing that fidelity in the English Stop-Smoking Services may be low and that routine monitoring is warranted.

Fidelity and outcomes in six integrated dual disorders treatment programs.

PubMed

Chandler, Daniel W

2011-02-01

Fidelity scores and outcomes were measured in six outpatient programs in California which implemented Integrated Dual Disorders Treatment (IDDT). Outcomes were measured for 1 year in four sites and 2 years in two sites; fidelity was assessed at 6 month intervals. Three of the six sites achieved high fidelity (at least a 4 on a 5 point fidelity scale) and three moderate fidelity (at least a 3). Retention in treatment, mental health functioning, stage of substance abuse treatment, abstinence, and psychiatric hospitalization were measured. Outcomes for individual programs were generally positive but not consistent within programs or across programs. Using pooled data in a longitudinal regression model with random effects at person level and adjustment of standard errors for clustering by site, change over time was not statistically significant for the primary outcomes. Fidelity scores had limited association with positive outcomes.

Commentary: Learning from Variations in Fidelity of Implementation

ERIC Educational Resources Information Center

Balu, Rekha; Doolittle, Fred

2016-01-01

The articles in this special issue discuss efforts to improve academic reading outcomes for students and ways to achieve high implementation fidelity of promising strategies. At times the authors discuss if--and how--strong fidelity is associated with strong outcomes and potentially even impacts (the difference between program and control group…

Preschool Children's Development in Classic Montessori, Supplemented Montessori, and Conventional Programs

ERIC Educational Resources Information Center

Lillard, Angeline S.

2012-01-01

Research on the outcomes of Montessori education is scarce and results are inconsistent. One possible reason for the inconsistency is variations in Montessori implementation fidelity. To test whether outcomes vary according to implementation fidelity, we examined preschool children enrolled in high fidelity classic Montessori programs, lower…

Uncertainty quantification for PZT bimorph actuators

NASA Astrophysics Data System (ADS)

Bravo, Nikolas; Smith, Ralph C.; Crews, John

2018-03-01

In this paper, we discuss the development of a high fidelity model for a PZT bimorph actuator used for micro-air vehicles, which includes the Robobee. We developed a high-fidelity model for the actuator using the homogenized energy model (HEM) framework, which quantifies the nonlinear, hysteretic, and rate-dependent behavior inherent to PZT in dynamic operating regimes. We then discussed an inverse problem on the model. We included local and global sensitivity analysis of the parameters in the high-fidelity model. Finally, we will discuss the results of Bayesian inference and uncertainty quantification on the HEM.

Benefits of computer screen-based simulation in learning cardiac arrest procedures.

PubMed

Bonnetain, Elodie; Boucheix, Jean-Michel; Hamet, Maël; Freysz, Marc

2010-07-01

What is the best way to train medical students early so that they acquire basic skills in cardiopulmonary resuscitation as effectively as possible? Studies have shown the benefits of high-fidelity patient simulators, but have also demonstrated their limits. New computer screen-based multimedia simulators have fewer constraints than high-fidelity patient simulators. In this area, as yet, there has been no research on the effectiveness of transfer of learning from a computer screen-based simulator to more realistic situations such as those encountered with high-fidelity patient simulators. We tested the benefits of learning cardiac arrest procedures using a multimedia computer screen-based simulator in 28 Year 2 medical students. Just before the end of the traditional resuscitation course, we compared two groups. An experiment group (EG) was first asked to learn to perform the appropriate procedures in a cardiac arrest scenario (CA1) in the computer screen-based learning environment and was then tested on a high-fidelity patient simulator in another cardiac arrest simulation (CA2). While the EG was learning to perform CA1 procedures in the computer screen-based learning environment, a control group (CG) actively continued to learn cardiac arrest procedures using practical exercises in a traditional class environment. Both groups were given the same amount of practice, exercises and trials. The CG was then also tested on the high-fidelity patient simulator for CA2, after which it was asked to perform CA1 using the computer screen-based simulator. Performances with both simulators were scored on a precise 23-point scale. On the test on a high-fidelity patient simulator, the EG trained with a multimedia computer screen-based simulator performed significantly better than the CG trained with traditional exercises and practice (16.21 versus 11.13 of 23 possible points, respectively; p<0.001). Computer screen-based simulation appears to be effective in preparing learners to use high-fidelity patient simulators, which present simulations that are closer to real-life situations.

Depth image enhancement using perceptual texture priors

NASA Astrophysics Data System (ADS)

Bang, Duhyeon; Shim, Hyunjung

2015-03-01

A depth camera is widely used in various applications because it provides a depth image of the scene in real time. However, due to the limited power consumption, the depth camera presents severe noises, incapable of providing the high quality 3D data. Although the smoothness prior is often employed to subside the depth noise, it discards the geometric details so to degrade the distance resolution and hinder achieving the realism in 3D contents. In this paper, we propose a perceptual-based depth image enhancement technique that automatically recovers the depth details of various textures, using a statistical framework inspired by human mechanism of perceiving surface details by texture priors. We construct the database composed of the high quality normals. Based on the recent studies in human visual perception (HVP), we select the pattern density as a primary feature to classify textures. Upon the classification results, we match and substitute the noisy input normals with high quality normals in the database. As a result, our method provides the high quality depth image preserving the surface details. We expect that our work is effective to enhance the details of depth image from 3D sensors and to provide a high-fidelity virtual reality experience.

Community Petascale Project for Accelerator Science and Simulation: Advancing Computational Science for Future Accelerators and Accelerator Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spentzouris, P.; /Fermilab; Cary, J.

The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessarymore » accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors. ComPASS is in the first year of executing its plan to develop the next-generation HPC accelerator modeling tools. ComPASS aims to develop an integrated simulation environment that will utilize existing and new accelerator physics modules with petascale capabilities, by employing modern computing and solver technologies. The ComPASS vision is to deliver to accelerator scientists a virtual accelerator and virtual prototyping modeling environment, with the necessary multiphysics, multiscale capabilities. The plan for this development includes delivering accelerator modeling applications appropriate for each stage of the ComPASS software evolution. Such applications are already being used to address challenging problems in accelerator design and optimization. The ComPASS organization for software development and applications accounts for the natural domain areas (beam dynamics, electromagnetics, and advanced acceleration), and all areas depend on the enabling technologies activities, such as solvers and component technology, to deliver the desired performance and integrated simulation environment. The ComPASS applications focus on computationally challenging problems important for design or performance optimization to all major HEP, NP, and BES accelerator facilities. With the cost and complexity of particle accelerators rising, the use of computation to optimize their designs and find improved operating regimes becomes essential, potentially leading to significant cost savings with modest investment.« less

High-fidelity data embedding for image annotation.

PubMed

He, Shan; Kirovski, Darko; Wu, Min

2009-02-01

High fidelity is a demanding requirement for data hiding, especially for images with artistic or medical value. This correspondence proposes a high-fidelity image watermarking for annotation with robustness to moderate distortion. To achieve the high fidelity of the embedded image, we introduce a visual perception model that aims at quantifying the local tolerance to noise for arbitrary imagery. Based on this model, we embed two kinds of watermarks: a pilot watermark that indicates the existence of the watermark and an information watermark that conveys a payload of several dozen bits. The objective is to embed 32 bits of metadata into a single image in such a way that it is robust to JPEG compression and cropping. We demonstrate the effectiveness of the visual model and the application of the proposed annotation technology using a database of challenging photographic and medical images that contain a large amount of smooth regions.

High Fidelity Tape Transfer Printing Based On Chemically Induced Adhesive Strength Modulation

NASA Astrophysics Data System (ADS)

Sim, Kyoseung; Chen, Song; Li, Yuhang; Kammoun, Mejdi; Peng, Yun; Xu, Minwei; Gao, Yang; Song, Jizhou; Zhang, Yingchun; Ardebili, Haleh; Yu, Cunjiang

2015-11-01

Transfer printing, a two-step process (i.e. picking up and printing) for heterogeneous integration, has been widely exploited for the fabrication of functional electronics system. To ensure a reliable process, strong adhesion for picking up and weak or no adhesion for printing are required. However, it is challenging to meet the requirements of switchable stamp adhesion. Here we introduce a simple, high fidelity process, namely tape transfer printing(TTP), enabled by chemically induced dramatic modulation in tape adhesive strength. We describe the working mechanism of the adhesion modulation that governs this process and demonstrate the method by high fidelity tape transfer printing several types of materials and devices, including Si pellets arrays, photodetector arrays, and electromyography (EMG) sensors, from their preparation substrates to various alien substrates. High fidelity tape transfer printing of components onto curvilinear surfaces is also illustrated.

Surrogate based wind farm layout optimization using manifold mapping

NASA Astrophysics Data System (ADS)

Kaja Kamaludeen, Shaafi M.; van Zuijle, Alexander; Bijl, Hester

2016-09-01

High computational cost associated with the high fidelity wake models such as RANS or LES serves as a primary bottleneck to perform a direct high fidelity wind farm layout optimization (WFLO) using accurate CFD based wake models. Therefore, a surrogate based multi-fidelity WFLO methodology (SWFLO) is proposed. The surrogate model is built using an SBO method referred as manifold mapping (MM). As a verification, optimization of spacing between two staggered wind turbines was performed using the proposed surrogate based methodology and the performance was compared with that of direct optimization using high fidelity model. Significant reduction in computational cost was achieved using MM: a maximum computational cost reduction of 65%, while arriving at the same optima as that of direct high fidelity optimization. The similarity between the response of models, the number of mapping points and its position, highly influences the computational efficiency of the proposed method. As a proof of concept, realistic WFLO of a small 7-turbine wind farm is performed using the proposed surrogate based methodology. Two variants of Jensen wake model with different decay coefficients were used as the fine and coarse model. The proposed SWFLO method arrived at the same optima as that of the fine model with very less number of fine model simulations.

High-fidelity teleportation beyond the no-cloning limit and entanglement swapping for continuous variables.

PubMed

Takei, Nobuyuki; Yonezawa, Hidehiro; Aoki, Takao; Furusawa, Akira

2005-06-10

We experimentally demonstrate continuous-variable quantum teleportation beyond the no-cloning limit. We teleport a coherent state and achieve the fidelity of 0.70 +/- 0.02 that surpasses the no-cloning limit of 2/3. Surpassing the limit is necessary to transfer the nonclassicality of an input quantum state. By using our high-fidelity teleporter, we demonstrate entanglement swapping, namely, teleportation of quantum entanglement, as an example of transfer of nonclassicality.

DOE Office of Scientific and Technical Information (OSTI.GOV)

McInerney, Peter; Adams, Paul; Hadi, Masood Z.

As larger-scale cloning projects become more prevalent, there is an increasing need for comparisons among high fidelity DNA polymerases used for PCR amplification. All polymerases marketed for PCR applications are tested for fidelity properties (i.e., error rate determination) by vendors, and numerous literature reports have addressed PCR enzyme fidelity. Nonetheless, it is often difficult to make direct comparisons among different enzymes due to numerous methodological and analytical differences from study to study. We have measured the error rates for 6 DNA polymerases commonly used in PCR applications, including 3 polymerases typically used for cloning applications requiring high fidelity. Error ratemore » measurement values reported here were obtained by direct sequencing of cloned PCR products. The strategy employed here allows interrogation of error rate across a very large DNA sequence space, since 94 unique DNA targets were used as templates for PCR cloning. The six enzymes included in the study, Taq polymerase, AccuPrime-Taq High Fidelity, KOD Hot Start, cloned Pfu polymerase, Phusion Hot Start, and Pwo polymerase, we find the lowest error rates with Pfu , Phusion, and Pwo polymerases. Error rates are comparable for these 3 enzymes and are >10x lower than the error rate observed with Taq polymerase. Mutation spectra are reported, with the 3 high fidelity enzymes displaying broadly similar types of mutations. For these enzymes, transition mutations predominate, with little bias observed for type of transition.« less

Error Rate Comparison during Polymerase Chain Reaction by DNA Polymerase

DOE PAGES

McInerney, Peter; Adams, Paul; Hadi, Masood Z.

2014-01-01

As larger-scale cloning projects become more prevalent, there is an increasing need for comparisons among high fidelity DNA polymerases used for PCR amplification. All polymerases marketed for PCR applications are tested for fidelity properties (i.e., error rate determination) by vendors, and numerous literature reports have addressed PCR enzyme fidelity. Nonetheless, it is often difficult to make direct comparisons among different enzymes due to numerous methodological and analytical differences from study to study. We have measured the error rates for 6 DNA polymerases commonly used in PCR applications, including 3 polymerases typically used for cloning applications requiring high fidelity. Error ratemore » measurement values reported here were obtained by direct sequencing of cloned PCR products. The strategy employed here allows interrogation of error rate across a very large DNA sequence space, since 94 unique DNA targets were used as templates for PCR cloning. The six enzymes included in the study, Taq polymerase, AccuPrime-Taq High Fidelity, KOD Hot Start, cloned Pfu polymerase, Phusion Hot Start, and Pwo polymerase, we find the lowest error rates with Pfu , Phusion, and Pwo polymerases. Error rates are comparable for these 3 enzymes and are >10x lower than the error rate observed with Taq polymerase. Mutation spectra are reported, with the 3 high fidelity enzymes displaying broadly similar types of mutations. For these enzymes, transition mutations predominate, with little bias observed for type of transition.« less

Trapped Ion Qubits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maunz, Peter; Wilhelm, Lukas

Qubits can be encoded in clock states of trapped ions. These states are well isolated from the environment resulting in long coherence times [1] while enabling efficient high-fidelity qubit interactions mediated by the Coulomb coupled motion of the ions in the trap. Quantum states can be prepared with high fidelity and measured efficiently using fluorescence detection. State preparation and detection with 99.93% fidelity have been realized in multiple systems [1,2]. Single qubit gates have been demonstrated below rigorous fault-tolerance thresholds [1,3]. Two qubit gates have been realized with more than 99.9% fidelity [4,5]. Quantum algorithms have been demonstrated on systemsmore » of 5 to 15 qubits [6–8].« less

Driving many distant atoms into high-fidelity steady state entanglement via Lyapunov control.

PubMed

Li, Chuang; Song, Jie; Xia, Yan; Ding, Weiqiang

2018-01-22

Based on Lyapunov control theory in closed and open systems, we propose a scheme to generate W state of many distant atoms in the cavity-fiber-cavity system. In the closed system, the W state is generated successfully even when the coupling strength between the cavity and fiber is extremely weak. In the presence of atomic spontaneous emission or cavity and fiber decay, the photon-measurement and quantum feedback approaches are proposed to improve the fidelity, which enable efficient generation of high-fidelity W state in the case of large dissipation. Furthermore, the time-optimal Lyapunov control is investigated to shorten the evolution time and improve the fidelity in open systems.

Multi-fidelity machine learning models for accurate bandgap predictions of solids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pilania, Ghanshyam; Gubernatis, James E.; Lookman, Turab

Here, we present a multi-fidelity co-kriging statistical learning framework that combines variable-fidelity quantum mechanical calculations of bandgaps to generate a machine-learned model that enables low-cost accurate predictions of the bandgaps at the highest fidelity level. Additionally, the adopted Gaussian process regression formulation allows us to predict the underlying uncertainties as a measure of our confidence in the predictions. In using a set of 600 elpasolite compounds as an example dataset and using semi-local and hybrid exchange correlation functionals within density functional theory as two levels of fidelities, we demonstrate the excellent learning performance of the method against actual high fidelitymore » quantum mechanical calculations of the bandgaps. The presented statistical learning method is not restricted to bandgaps or electronic structure methods and extends the utility of high throughput property predictions in a significant way.« less

Multi-fidelity machine learning models for accurate bandgap predictions of solids

DOE PAGES

Pilania, Ghanshyam; Gubernatis, James E.; Lookman, Turab

2016-12-28

Here, we present a multi-fidelity co-kriging statistical learning framework that combines variable-fidelity quantum mechanical calculations of bandgaps to generate a machine-learned model that enables low-cost accurate predictions of the bandgaps at the highest fidelity level. Additionally, the adopted Gaussian process regression formulation allows us to predict the underlying uncertainties as a measure of our confidence in the predictions. In using a set of 600 elpasolite compounds as an example dataset and using semi-local and hybrid exchange correlation functionals within density functional theory as two levels of fidelities, we demonstrate the excellent learning performance of the method against actual high fidelitymore » quantum mechanical calculations of the bandgaps. The presented statistical learning method is not restricted to bandgaps or electronic structure methods and extends the utility of high throughput property predictions in a significant way.« less

Hydropower Optimization Using Artificial Neural Network Surrogate Models of a High-Fidelity Hydrodynamics and Water Quality Model

NASA Astrophysics Data System (ADS)

Shaw, Amelia R.; Smith Sawyer, Heather; LeBoeuf, Eugene J.; McDonald, Mark P.; Hadjerioua, Boualem

2017-11-01

Hydropower operations optimization subject to environmental constraints is limited by challenges associated with dimensionality and spatial and temporal resolution. The need for high-fidelity hydrodynamic and water quality models within optimization schemes is driven by improved computational capabilities, increased requirements to meet specific points of compliance with greater resolution, and the need to optimize operations of not just single reservoirs but systems of reservoirs. This study describes an important advancement for computing hourly power generation schemes for a hydropower reservoir using high-fidelity models, surrogate modeling techniques, and optimization methods. The predictive power of the high-fidelity hydrodynamic and water quality model CE-QUAL-W2 is successfully emulated by an artificial neural network, then integrated into a genetic algorithm optimization approach to maximize hydropower generation subject to constraints on dam operations and water quality. This methodology is applied to a multipurpose reservoir near Nashville, Tennessee, USA. The model successfully reproduced high-fidelity reservoir information while enabling 6.8% and 6.6% increases in hydropower production value relative to actual operations for dissolved oxygen (DO) limits of 5 and 6 mg/L, respectively, while witnessing an expected decrease in power generation at more restrictive DO constraints. Exploration of simultaneous temperature and DO constraints revealed capability to address multiple water quality constraints at specified locations. The reduced computational requirements of the new modeling approach demonstrated an ability to provide decision support for reservoir operations scheduling while maintaining high-fidelity hydrodynamic and water quality information as part of the optimization decision support routines.

Barriers and enablers to the use of high-fidelity patient simulation manikins in nurse education: an integrative review.

PubMed

Al-Ghareeb, Amal Z; Cooper, Simon J

2016-01-01

This integrative review identified, critically appraised and synthesised the existing evidence on the barriers and enablers to using high-fidelity human patient simulator manikins (HPSMs) in undergraduate nursing education. In nursing education, specifically at the undergraduate level, a range of low to high-fidelity simulations have been used as teaching aids. However, nursing educators encounter challenges when introducing new teaching methods or technology, despite the prevalence of high-fidelity HPSMs in nursing education. An integrative review adapted a systematic approach. Medline, CINAHL plus, ERIC, PsychINFO, EMBASE, SCOPUS, Science Direct, Cochrane database, Joanna Brigge Institute, ProQuest, California Simulation Alliance, Simulation Innovative Recourses Center and the search engine Google Scholar were searched. Keywords were selected and specific inclusion/exclusion criteria were applied. The review included all research designs for papers published between 2000 and 2015 that identified the barriers and enablers to using high-fidelity HPSMs in undergraduate nursing education. Studies were appraised using the Critical Appraisal Skills Programme criteria. Thematic analysis was undertaken and emergent themes were extracted. Twenty-one studies were included in the review. These studies adopted quasi-experimental, prospective non-experimental and descriptive designs. Ten barriers were identified, including "lack of time," "fear of technology" and "workload issues." Seven enablers were identified, including "faculty training," "administrative support" and a "dedicated simulation coordinator." Barriers to simulation relate specifically to the complex technologies inherent in high-fidelity HPSMs approaches. Strategic approaches that support up-skilling and provide dedicated technological support may overcome these barriers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hydropower Optimization Using Artificial Neural Network Surrogate Models of a High-Fidelity Hydrodynamics and Water Quality Model

DOE PAGES

Shaw, Amelia R.; Sawyer, Heather Smith; LeBoeuf, Eugene J.; ...

2017-10-24

Hydropower operations optimization subject to environmental constraints is limited by challenges associated with dimensionality and spatial and temporal resolution. The need for high-fidelity hydrodynamic and water quality models within optimization schemes is driven by improved computational capabilities, increased requirements to meet specific points of compliance with greater resolution, and the need to optimize operations of not just single reservoirs but systems of reservoirs. This study describes an important advancement for computing hourly power generation schemes for a hydropower reservoir using high-fidelity models, surrogate modeling techniques, and optimization methods. The predictive power of the high-fidelity hydrodynamic and water quality model CE-QUAL-W2more » is successfully emulated by an artificial neural network, then integrated into a genetic algorithm optimization approach to maximize hydropower generation subject to constraints on dam operations and water quality. This methodology is applied to a multipurpose reservoir near Nashville, Tennessee, USA. The model successfully reproduced high-fidelity reservoir information while enabling 6.8% and 6.6% increases in hydropower production value relative to actual operations for dissolved oxygen (DO) limits of 5 and 6 mg/L, respectively, while witnessing an expected decrease in power generation at more restrictive DO constraints. Exploration of simultaneous temperature and DO constraints revealed capability to address multiple water quality constraints at specified locations. Here, the reduced computational requirements of the new modeling approach demonstrated an ability to provide decision support for reservoir operations scheduling while maintaining high-fidelity hydrodynamic and water quality information as part of the optimization decision support routines.« less

Utilizing Three-Dimensional Printing Technology to Assess the Feasibility of High-Fidelity Synthetic Ventricular Septal Defect Models for Simulation in Medical Education.

PubMed

Costello, John P; Olivieri, Laura J; Krieger, Axel; Thabit, Omar; Marshall, M Blair; Yoo, Shi-Joon; Kim, Peter C; Jonas, Richard A; Nath, Dilip S

2014-07-01

The current educational approach for teaching congenital heart disease (CHD) anatomy to students involves instructional tools and techniques that have significant limitations. This study sought to assess the feasibility of utilizing present-day three-dimensional (3D) printing technology to create high-fidelity synthetic heart models with ventricular septal defect (VSD) lesions and applying these models to a novel, simulation-based educational curriculum for premedical and medical students. Archived, de-identified magnetic resonance images of five common VSD subtypes were obtained. These cardiac images were then segmented and built into 3D computer-aided design models using Mimics Innovation Suite software. An Objet500 Connex 3D printer was subsequently utilized to print a high-fidelity heart model for each VSD subtype. Next, a simulation-based educational curriculum using these heart models was developed and implemented in the instruction of 29 premedical and medical students. Assessment of this curriculum was undertaken with Likert-type questionnaires. High-fidelity VSD models were successfully created utilizing magnetic resonance imaging data and 3D printing. Following instruction with these high-fidelity models, all students reported significant improvement in knowledge acquisition (P < .0001), knowledge reporting (P < .0001), and structural conceptualization (P < .0001) of VSDs. It is feasible to use present-day 3D printing technology to create high-fidelity heart models with complex intracardiac defects. Furthermore, this tool forms the foundation for an innovative, simulation-based educational approach to teach students about CHD and creates a novel opportunity to stimulate their interest in this field. © The Author(s) 2014.

Hydropower Optimization Using Artificial Neural Network Surrogate Models of a High-Fidelity Hydrodynamics and Water Quality Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaw, Amelia R.; Sawyer, Heather Smith; LeBoeuf, Eugene J.

Hydropower operations optimization subject to environmental constraints is limited by challenges associated with dimensionality and spatial and temporal resolution. The need for high-fidelity hydrodynamic and water quality models within optimization schemes is driven by improved computational capabilities, increased requirements to meet specific points of compliance with greater resolution, and the need to optimize operations of not just single reservoirs but systems of reservoirs. This study describes an important advancement for computing hourly power generation schemes for a hydropower reservoir using high-fidelity models, surrogate modeling techniques, and optimization methods. The predictive power of the high-fidelity hydrodynamic and water quality model CE-QUAL-W2more » is successfully emulated by an artificial neural network, then integrated into a genetic algorithm optimization approach to maximize hydropower generation subject to constraints on dam operations and water quality. This methodology is applied to a multipurpose reservoir near Nashville, Tennessee, USA. The model successfully reproduced high-fidelity reservoir information while enabling 6.8% and 6.6% increases in hydropower production value relative to actual operations for dissolved oxygen (DO) limits of 5 and 6 mg/L, respectively, while witnessing an expected decrease in power generation at more restrictive DO constraints. Exploration of simultaneous temperature and DO constraints revealed capability to address multiple water quality constraints at specified locations. Here, the reduced computational requirements of the new modeling approach demonstrated an ability to provide decision support for reservoir operations scheduling while maintaining high-fidelity hydrodynamic and water quality information as part of the optimization decision support routines.« less

Aerodynamic design applying automatic differentiation and using robust variable fidelity optimization

NASA Astrophysics Data System (ADS)

Takemiya, Tetsushi

In modern aerospace engineering, the physics-based computational design method is becoming more important, as it is more efficient than experiments and because it is more suitable in designing new types of aircraft (e.g., unmanned aerial vehicles or supersonic business jets) than the conventional design method, which heavily relies on historical data. To enhance the reliability of the physics-based computational design method, researchers have made tremendous efforts to improve the fidelity of models. However, high-fidelity models require longer computational time, so the advantage of efficiency is partially lost. This problem has been overcome with the development of variable fidelity optimization (VFO). In VFO, different fidelity models are simultaneously employed in order to improve the speed and the accuracy of convergence in an optimization process. Among the various types of VFO methods, one of the most promising methods is the approximation management framework (AMF). In the AMF, objective and constraint functions of a low-fidelity model are scaled at a design point so that the scaled functions, which are referred to as "surrogate functions," match those of a high-fidelity model. Since scaling functions and the low-fidelity model constitutes surrogate functions, evaluating the surrogate functions is faster than evaluating the high-fidelity model. Therefore, in the optimization process, in which gradient-based optimization is implemented and thus many function calls are required, the surrogate functions are used instead of the high-fidelity model to obtain a new design point. The best feature of the AMF is that it may converge to a local optimum of the high-fidelity model in much less computational time than the high-fidelity model. However, through literature surveys and implementations of the AMF, the author xx found that (1) the AMF is very vulnerable when the computational analysis models have numerical noise, which is very common in high-fidelity models, and that (2) the AMF terminates optimization erroneously when the optimization problems have constraints. The first problem is due to inaccuracy in computing derivatives in the AMF, and the second problem is due to erroneous treatment of the trust region ratio, which sets the size of the domain for an optimization in the AMF. In order to solve the first problem of the AMF, automatic differentiation (AD) technique, which reads the codes of analysis models and automatically generates new derivative codes based on some mathematical rules, is applied. If derivatives are computed with the generated derivative code, they are analytical, and the required computational time is independent of the number of design variables, which is very advantageous for realistic aerospace engineering problems. However, if analysis models implement iterative computations such as computational fluid dynamics (CFD), which solves system partial differential equations iteratively, computing derivatives through the AD requires a massive memory size. The author solved this deficiency by modifying the AD approach and developing a more efficient implementation with CFD, and successfully applied the AD to general CFD software. In order to solve the second problem of the AMF, the governing equation of the trust region ratio, which is very strict against the violation of constraints, is modified so that it can accept the violation of constraints within some tolerance. By accepting violations of constraints during the optimization process, the AMF can continue optimization without terminating immaturely and eventually find the true optimum design point. With these modifications, the AMF is referred to as "Robust AMF," and it is applied to airfoil and wing aerodynamic design problems using Euler CFD software. The former problem has 21 design variables, and the latter 64. In both problems, derivatives computed with the proposed AD method are first compared with those computed with the finite differentiation (FD) method, and then, the Robust AMF is implemented along with the sequential quadratic programming (SQP) optimization method with only high-fidelity models. The proposed AD method computes derivatives more accurately and faster than the FD method, and the Robust AMF successfully optimizes shapes of the airfoil and the wing in a much shorter time than SQP with only high-fidelity models. These results clearly show the effectiveness of the Robust AMF. Finally, the feasibility of reducing computational time for calculating derivatives and the necessity of AMF with an optimum design point always in the feasible region are discussed as future work.

Effect of laser pulse shaping parameters on the fidelity of quantum logic gates.

PubMed

Zaari, Ryan R; Brown, Alex

2012-09-14

The effect of varying parameters specific to laser pulse shaping instruments on resulting fidelities for the ACNOT(1), NOT(2), and Hadamard(2) quantum logic gates are studied for the diatomic molecule (12)C(16)O. These parameters include varying the frequency resolution, adjusting the number of frequency components and also varying the amplitude and phase at each frequency component. A time domain analytic form of the original discretized frequency domain laser pulse function is derived, providing a useful means to infer the resulting pulse shape through variations to the aforementioned parameters. We show that amplitude variation at each frequency component is a crucial requirement for optimal laser pulse shaping, whereas phase variation provides minimal contribution. We also show that high fidelity laser pulses are dependent upon the frequency resolution and increasing the number of frequency components provides only a small incremental improvement to quantum gate fidelity. Analysis through use of the pulse area theorem confirms the resulting population dynamics for one or two frequency high fidelity laser pulses and implies similar dynamics for more complex laser pulse shapes. The ability to produce high fidelity laser pulses that provide both population control and global phase alignment is attributed greatly to the natural evolution phase alignment of the qubits involved within the quantum logic gate operation.

Evaluation of Pseudo-Haptic Interactions with Soft Objects in Virtual Environments.

PubMed

Li, Min; Sareh, Sina; Xu, Guanghua; Ridzuan, Maisarah Binti; Luo, Shan; Xie, Jun; Wurdemann, Helge; Althoefer, Kaspar

2016-01-01

This paper proposes a pseudo-haptic feedback method conveying simulated soft surface stiffness information through a visual interface. The method exploits a combination of two feedback techniques, namely visual feedback of soft surface deformation and control of the indenter avatar speed, to convey stiffness information of a simulated surface of a soft object in virtual environments. The proposed method was effective in distinguishing different sizes of virtual hard nodules integrated into the simulated soft bodies. To further improve the interactive experience, the approach was extended creating a multi-point pseudo-haptic feedback system. A comparison with regards to (a) nodule detection sensitivity and (b) elapsed time as performance indicators in hard nodule detection experiments to a tablet computer incorporating vibration feedback was conducted. The multi-point pseudo-haptic interaction is shown to be more time-efficient than the single-point pseudo-haptic interaction. It is noted that multi-point pseudo-haptic feedback performs similarly well when compared to a vibration-based feedback method based on both performance measures elapsed time and nodule detection sensitivity. This proves that the proposed method can be used to convey detailed haptic information for virtual environmental tasks, even subtle ones, using either a computer mouse or a pressure sensitive device as an input device. This pseudo-haptic feedback method provides an opportunity for low-cost simulation of objects with soft surfaces and hard inclusions, as, for example, occurring in ever more realistic video games with increasing emphasis on interaction with the physical environment and minimally invasive surgery in the form of soft tissue organs with embedded cancer nodules. Hence, the method can be used in many low-budget applications where haptic sensation is required, such as surgeon training or video games, either using desktop computers or portable devices, showing reasonably high fidelity in conveying stiffness perception to the user.

State resolved vibrational relaxation modeling for strongly nonequilibrium flows

NASA Astrophysics Data System (ADS)

Boyd, Iain D.; Josyula, Eswar

2011-05-01

Vibrational relaxation is an important physical process in hypersonic flows. Activation of the vibrational mode affects the fundamental thermodynamic properties and finite rate relaxation can reduce the degree of dissociation of a gas. Low fidelity models of vibrational activation employ a relaxation time to capture the process at a macroscopic level. High fidelity, state-resolved models have been developed for use in continuum gas dynamics simulations based on computational fluid dynamics (CFD). By comparison, such models are not as common for use with the direct simulation Monte Carlo (DSMC) method. In this study, a high fidelity, state-resolved vibrational relaxation model is developed for the DSMC technique. The model is based on the forced harmonic oscillator approach in which multi-quantum transitions may become dominant at high temperature. Results obtained for integrated rate coefficients from the DSMC model are consistent with the corresponding CFD model. Comparison of relaxation results obtained with the high-fidelity DSMC model shows significantly less excitation of upper vibrational levels in comparison to the standard, lower fidelity DSMC vibrational relaxation model. Application of the new DSMC model to a Mach 7 normal shock wave in carbon monoxide provides better agreement with experimental measurements than the standard DSMC relaxation model.

Visual Stability of Objects and Environments Viewed through Head-Mounted Displays

NASA Technical Reports Server (NTRS)

Ellis, Stephen R.; Adelstein, Bernard D.

2015-01-01

Virtual Environments (aka Virtual Reality) is again catching the public imagination and a number of startups (e.g. Oculus) and even not-so-startup companies (e.g. Microsoft) are trying to develop display systems to capitalize on this renewed interest. All acknowledge that this time they will get it right by providing the required dynamic fidelity, visual quality, and interesting content for the concept of VR to take off and change the world in ways it failed to do so in past incarnations. Some of the surprisingly long historical background of the technology that the form of direct simulation that underlies virtual environment and augmented reality displays will be briefly reviewed. An example of a mid 1990's augmented reality display system with good dynamic performance from our lab will be used to illustrate some of the underlying phenomena and technology concerning visual stability of virtual environments and objects during movement. In conclusion some idealized performance characteristics for a reference system will be proposed. Interestingly, many systems more or less on the market now may actually meet many of these proposed technical requirements. This observation leads to the conclusion that the current success of the IT firms trying to commercialize the technology will depend on the hidden costs of using the systems as well as the development of interesting and compelling content.

Effects of Low- Versus High-Fidelity Simulations on the Cognitive Burden and Performance of Entry-Level Paramedicine Students: A Mixed-Methods Comparison Trial Using Eye-Tracking, Continuous Heart Rate, Difficulty Rating Scales, Video Observation and Interviews.

PubMed

Mills, Brennen W; Carter, Owen B-J; Rudd, Cobie J; Claxton, Louise A; Ross, Nathan P; Strobel, Natalie A

2016-02-01

High-fidelity simulation-based training is often avoided for early-stage students because of the assumption that while practicing newly learned skills, they are ill suited to processing multiple demands, which can lead to "cognitive overload" and poorer learning outcomes. We tested this assumption using a mixed-methods experimental design manipulating psychological immersion. Thirty-nine randomly assigned first-year paramedicine students completed low- or high-environmental fidelity simulations [low-environmental fidelity simulations (LF(en)S) vs. high-environmental fidelity simulation (HF(en)S)] involving a manikin with obstructed airway (SimMan3G). Psychological immersion and cognitive burden were determined via continuous heart rate, eye tracking, self-report questionnaire (National Aeronautics and Space Administration Task Load Index), independent observation, and postsimulation interviews. Performance was assessed by successful location of obstruction and time-to-termination. Eye tracking confirmed that students attended to multiple, concurrent stimuli in HF(en)S and interviews consistently suggested that they experienced greater psychological immersion and cognitive burden than their LF(en)S counterparts. This was confirmed by significantly higher mean heart rate (P < 0.001) and National Aeronautics and Space Administration Task Load Index mental demand (P < 0.05). Although group allocation did not influence the proportion of students who ultimately revived the patient (58% vs. 30%, P < 0.10), the HF(en)S students did so significantly more quickly (P < 0.01). The LF(en)S students had low immersion resulting in greater assessment anxiety. High-environmental fidelity simulation engendered immersion and a sense of urgency in students, whereas LF(en)S created assessment anxiety and slower performance. We conclude that once early-stage students have learned the basics of a clinical skill, throwing them in the "deep end" of high-fidelity simulation creates significant additional cognitive burden but this has considerable educational merit.

Final Environmental Assessment for the Installation of New JDAM and High Fidelity Targets for the Nevada Test and Training Range

DTIC Science & Technology

2004-11-01

Target Centroid 98 RANW / R SC GIS 04071 Data valid as of 11 Mar 04 rogertargets_a#2.apr Figure 2-3. Chemical/Industrial and High Fidelity Urban...existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding...Fidelity Targets, NTTR Nevada Division of Wildlife – Nevada Test and Training Range JDAM Targets Nevada Natural Heritage Program – Data Request received 8

High-fidelity frequency down-conversion of visible entangled photon pairs with superconducting single-photon detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ikuta, Rikizo; Kato, Hiroshi; Kusaka, Yoshiaki

We experimentally demonstrate a high-fidelity visible-to-telecommunicationwavelength conversion of a photon by using a solid-state-based difference frequency generation. In the experiment, one half of a pico-second visible entangled photon pair at 780 nm is converted to a 1522-nm photon. Using superconducting single-photon detectors with low dark count rates and small timing jitters, we observed a fidelity of 0.93±0.04 after the wavelength conversion.

Does the virtual refractor patient-simulator improve student competency when refracting in the consulting room?

PubMed

Alhazmi, Mohammed S; Butler, Craig W; Junghans, Barbara M

2018-06-12

The use of patient simulators in ophthalmic education appears limited. This study examines the effects of the addition of the 'Virtual Refractor' patient simulator learning activity into a short unit preparing students to determine the power of the spectacle lenses required by patients in a clinic. Twenty-four year one optometry students were randomly assigned to either the simulator-intervention group (n = 12) or the non-intervention group. All students attended tutorials on refraction and the use of a refractor-head. Simulator-intervention students additionally attended a tutorial on the Virtual Refractor. All answered a questionnaire concerning time spent studying, perceived knowledge and confidence. Twenty-four short-sighted patients were recruited. Two refractions per student were timed and the accuracy compared with that of an experienced optometrist. Ten students from each group completed the study. Students who used the simulator were significantly (p < 0.05) more accurate at a clinical level (within 0.22 ± 0.22 DS, 95 per cent CI 0.12-0.32) than those who did not (within 0.60 ± 0.67 DS, 95 per cent CI 0.29-0.92) and 13 per cent quicker (4.7 minutes, p < 0.05). Students who used the simulator felt more knowledgeable (p < 0.05) and confident (p < 0.05), but had spent more time reading about refraction and practised on the Virtual Refractor at home for 5.7 ± 1.3 hours. The Virtual Refractor has many features of high-fidelity medical simulation known to lead to effective learning and it also offers flexible independent learning without a concomitant increase in the student time-burden. The improved accuracy and speed on first patient encounters found in this study validates the use of this patient simulator as a useful bridge for students early in training to successfully transfer theoretical knowledge prior to entering the consulting room. The translational benefits resulting from compulsory learning activities on a patient simulator can lead to reduced demands on infrastructure and clinical supervision. © 2018 Optometry Australia.

Design and multifidelity analysis of dual mode scramjet compression system using coupled NPSS and fluent simulation

NASA Astrophysics Data System (ADS)

Vijayakumar, Nandakumar

Hypersonic airbreathing engines mark a potential future development of the aerospace industry and immense efforts have been taken in gaining knowledge in them for the past decades. The physical phenomenon occurring at the hypersonic flow regime makes the design and performance prediction of a scramjet engine hard. Though cutting-edge simulation tools fight their way toward accurate prediction of the environment, the time consumed by the entire process in designing and analyzing a scramjet engine and its component may be exorbitant. A multi-fidelity approach for designing a scramjet with a cruising Mach number of 6 is detailed in this research where high-order simulations are applied according to the physics involved in the component. Two state-of-the-art simulation tools were used to take the aerodynamic and propulsion disciplines into account for realistic prediction of the individual components as well as the entire scramjet. The specific goal of this research is to create a virtual environment to design and analyze a hypersonic, two-dimensional, planar inlet and isolator to check its operability for a dual-mode scramjet engine. The dual mode scramjet engine starts at a Mach number of 3.5 where it operates as a ramjet and accelerates to Mach 6 to be operated as a scramjet engine. The intercomponent interaction between the compression components with the rest of the engine is studied by varying the fidelity of the numerical simulation according to the complexity of the situation. Efforts have been taken to track the transition Mach number as it switches from ramjet to scramjet. A complete scramjet assembly was built using the Numerical Propulsion Simulation System (NPSS) and the performance of the engine was evaluated for various scenarios. Different numerical techniques were opted for varying the fidelity of the analysis with the highest fidelity consisting of 2D RANS CFD simulation. The interaction between the NPSS elements with the CFD solver is governed by the top-level assembly solver of NPSS. The importance of intercomponent interactions are discussed. The methodology used in this research for design and analysis, should add up to provide an efficient way for estimating the design and off-design operating modes of a dual mode scramjet engine.

Comparison of intervention fidelity between COPE TEEN and an attention-control program in a randomized controlled trial

PubMed Central

Kelly, Stephanie A.; Oswalt, Krista; Melnyk, Bernadette Mazurek; Jacobson, Diana

2015-01-01

Fidelity in implementing an intervention is critical to accurately determine and interpret the effects of an intervention. It is important to monitor the manner in which the behavioral intervention is implemented (e.g. adaptations, delivery as intended and dose). Few interventions are implemented with 100% fidelity. In this study, high school health teachers implemented the intervention. To attribute study findings to the intervention, it was vital to know to what degree the intervention was implemented. Therefore, the purposes of this study were to evaluate intervention fidelity and to compare implementation fidelity between the creating opportunities for personal empowerment (COPE) Healthy Lifestyles TEEN (thinking, emotions, exercise, and nutrition) program, the experimental intervention and Healthy Teens, an attention-control intervention, in a randomized controlled trial with 779 adolescents from 11 high schools in the southwest region of the United States. Thirty teachers participated in this study. Findings indicated that the attention-control teachers implemented their intervention with greater fidelity than COPE TEEN teachers. It is possible due to the novel intervention and the teachers’ unfamiliarity with cognitive-behavioral skills building, COPE TEEN teachers had less fidelity. It is important to assess novel skill development prior to the commencement of experimental interventions and to provide corrective feedback during the course of implementation. PMID:25355179

Orbit Stability of OSIRIS-REx in the Vicinity of Bennu Using a High-Fidelity Solar Radiation Model

NASA Technical Reports Server (NTRS)

Williams, Trevor; Hughes, Kyle; Mashiku, Alinda; Longuski, James

2015-01-01

The OSIRIS-REx mission (Origins Spectral Interpretation Resource Identification Security Regolith EXPlorer) is an asteroid sample return mission to Bennu (RQ36) that is scheduled to launch in 2016. The planned science operations precluding the small retrieval involve operations in terminator orbits (orbit plane is perpendicular to the sun). Over longer durations the solar radiation pressure (SRP) perturbs the orbit causing it to precess. Our work involves: modeling high fidelity SRP model to capture the perturbations during attitude changes; design a stable orbit from the high fidelity models to analyze the stability over time.

Lattice Boltzmann for Airframe Noise Predictions

NASA Technical Reports Server (NTRS)

Barad, Michael; Kocheemoolayil, Joseph; Kiris, Cetin

2017-01-01

Increase predictive use of High-Fidelity Computational Aero- Acoustics (CAA) capabilities for NASA's next generation aviation concepts. CFD has been utilized substantially in analysis and design for steady-state problems (RANS). Computational resources are extremely challenged for high-fidelity unsteady problems (e.g. unsteady loads, buffet boundary, jet and installation noise, fan noise, active flow control, airframe noise, etc) ü Need novel techniques for reducing the computational resources consumed by current high-fidelity CAA Need routine acoustic analysis of aircraft components at full-scale Reynolds number from first principles Need an order of magnitude reduction in wall time to solution!

Testing the Predictive Capability of the High-Fidelity Generalized Method of Cells Using an Efficient Reformulation

NASA Technical Reports Server (NTRS)

Arnold, Steven M. (Technical Monitor); Bansal, Yogesh; Pindera, Marek-Jerzy

2004-01-01

The High-Fidelity Generalized Method of Cells is a new micromechanics model for unidirectionally reinforced periodic multiphase materials that was developed to overcome the original model's shortcomings. The high-fidelity version predicts the local stress and strain fields with dramatically greater accuracy relative to the original model through the use of a better displacement field representation. Herein, we test the high-fidelity model's predictive capability in estimating the elastic moduli of periodic composites characterized by repeating unit cells obtained by rotation of an infinite square fiber array through an angle about the fiber axis. Such repeating unit cells may contain a few or many fibers, depending on the rotation angle. In order to analyze such multi-inclusion repeating unit cells efficiently, the high-fidelity micromechanics model's framework is reformulated using the local/global stiffness matrix approach. The excellent agreement with the corresponding results obtained from the standard transformation equations confirms the new model's predictive capability for periodic composites characterized by multi-inclusion repeating unit cells lacking planes of material symmetry. Comparison of the effective moduli and local stress fields with the corresponding results obtained from the original Generalized Method of Cells dramatically highlights the original model's shortcomings for certain classes of unidirectional composites.

High fidelity quasi steady-state aerodynamic model effects on race vehicle performance predictions using multi-body simulation

NASA Astrophysics Data System (ADS)

Mohrfeld-Halterman, J. A.; Uddin, M.

2016-07-01

We described in this paper the development of a high fidelity vehicle aerodynamic model to fit wind tunnel test data over a wide range of vehicle orientations. We also present a comparison between the effects of this proposed model and a conventional quasi steady-state aerodynamic model on race vehicle simulation results. This is done by implementing both of these models independently in multi-body quasi steady-state simulations to determine the effects of the high fidelity aerodynamic model on race vehicle performance metrics. The quasi steady state vehicle simulation is developed with a multi-body NASCAR Truck vehicle model, and simulations are conducted for three different types of NASCAR race tracks, a short track, a one and a half mile intermediate track, and a higher speed, two mile intermediate race track. For each track simulation, the effects of the aerodynamic model on handling, maximum corner speed, and drive force metrics are analysed. The accuracy of the high-fidelity model is shown to reduce the aerodynamic model error relative to the conventional aerodynamic model, and the increased accuracy of the high fidelity aerodynamic model is found to have realisable effects on the performance metric predictions on the intermediate tracks resulting from the quasi steady-state simulation.

Integrated tokamak modeling: when physics informs engineering and research planning

NASA Astrophysics Data System (ADS)

Poli, Francesca

2017-10-01

Simulations that integrate virtually all the relevant engineering and physics aspects of a real tokamak experiment are a power tool for experimental interpretation, model validation and planning for both present and future devices. This tutorial will guide through the building blocks of an ``integrated'' tokamak simulation, such as magnetic flux diffusion, thermal, momentum and particle transport, external heating and current drive sources, wall particle sources and sinks. Emphasis is given to the connection and interplay between external actuators and plasma response, between the slow time scales of the current diffusion and the fast time scales of transport, and how reduced and high-fidelity models can contribute to simulate a whole device. To illustrate the potential and limitations of integrated tokamak modeling for discharge prediction, a helium plasma scenario for the ITER pre-nuclear phase is taken as an example. This scenario presents challenges because it requires core-edge integration and advanced models for interaction between waves and fast-ions, which are subject to a limited experimental database for validation and guidance. Starting from a scenario obtained by re-scaling parameters from the demonstration inductive ``ITER baseline'', it is shown how self-consistent simulations that encompass both core and edge plasma regions, as well as high-fidelity heating and current drive source models are needed to set constraints on the density, magnetic field and heating scheme. This tutorial aims at demonstrating how integrated modeling, when used with adequate level of criticism, can not only support design of operational scenarios, but also help to asses the limitations and gaps in the available models, thus indicating where improved modeling tools are required and how present experiments can help their validation and inform research planning. Work supported by DOE under DE-AC02-09CH1146.

Applying the Five-Step Model of Fidelity Assessment to a Randomized Experiment of a High School STEM Intervention

ERIC Educational Resources Information Center

Kopp, Jason P.; Hulleman, Chris S.; Harackiewicz, Judith M.; Rozek, Chris

2012-01-01

Assessing fidelity of implementation is becoming increasingly important in education research, in particular as a tool for understanding variations in treatment effectiveness. Fidelity of implementation is defined as "the determination of how well an intervention is implemented in comparison with the original program design during an efficacy…

A trial of e-simulation of sudden patient deterioration (FIRST2ACT WEB) on student learning.

PubMed

Bogossian, Fiona E; Cooper, Simon J; Cant, Robyn; Porter, Joanne; Forbes, Helen

2015-10-01

High-fidelity simulation pedagogy is of increasing importance in health professional education; however, face-to-face simulation programs are resource intensive and impractical to implement across large numbers of students. To investigate undergraduate nursing students' theoretical and applied learning in response to the e-simulation program-FIRST2ACT WEBTM, and explore predictors of virtual clinical performance. Multi-center trial of FIRST2ACT WEBTM accessible to students in five Australian universities and colleges, across 8 campuses. A population of 489 final-year nursing students in programs of study leading to license to practice. Participants proceeded through three phases: (i) pre-simulation-briefing and assessment of clinical knowledge and experience; (ii) e-simulation-three interactive e-simulation clinical scenarios which included video recordings of patients with deteriorating conditions, interactive clinical tasks, pop up responses to tasks, and timed performance; and (iii) post-simulation feedback and evaluation. Descriptive statistics were followed by bivariate analysis to detect any associations, which were further tested using standard regression analysis. Of 409 students who commenced the program (83% response rate), 367 undergraduate nursing students completed the web-based program in its entirety, yielding a completion rate of 89.7%; 38.1% of students achieved passing clinical performance across three scenarios, and the proportion achieving passing clinical knowledge increased from 78.15% pre-simulation to 91.6% post-simulation. Knowledge was the main independent predictor of clinical performance in responding to a virtual deteriorating patient R(2)=0.090, F(7, 352)=4.962, p<0.001. The use of web-based technology allows simulation activities to be accessible to a large number of participants and completion rates indicate that 'Net Generation' nursing students were highly engaged with this mode of learning. The web-based e-simulation program FIRST2ACTTM effectively enhanced knowledge, virtual clinical performance, and self-assessed knowledge, skills, confidence, and competence in final-year nursing students. Copyright © 2015 Elsevier Ltd. All rights reserved.

Prospective randomized comparison of standard didactic lecture versus high-fidelity simulation for radiology resident contrast reaction management training.

PubMed

Wang, Carolyn L; Schopp, Jennifer G; Petscavage, Jonelle M; Paladin, Angelisa M; Richardson, Michael L; Bush, William H

2011-06-01

The objective of our study was to assess whether high-fidelity simulation-based training is more effective than traditional didactic lecture to train radiology residents in the management of contrast reactions. This was a prospective study of 44 radiology residents randomized into a simulation group versus a lecture group. All residents attended a contrast reaction didactic lecture. Four months later, baseline knowledge was assessed with a written test, which we refer to as the "pretest." After the pretest, the 21 residents in the lecture group attended a repeat didactic lecture and the 23 residents in the simulation group underwent high-fidelity simulation-based training with five contrast reaction scenarios. Next, all residents took a second written test, which we refer to as the "posttest." Two months after the posttest, both groups took a third written test, which we refer to as the "delayed posttest," and underwent performance testing with a high-fidelity severe contrast reaction scenario graded on predefined critical actions. There was no statistically significant difference between the simulation and lecture group pretest, immediate posttest, or delayed posttest scores. The simulation group performed better than the lecture group on the severe contrast reaction simulation scenario (p = 0.001). The simulation group reported improved comfort in identifying and managing contrast reactions and administering medications after the simulation training (p ≤ 0.04) and was more comfortable than the control group (p = 0.03), which reported no change in comfort level after the repeat didactic lecture. When compared with didactic lecture, high-fidelity simulation-based training of contrast reaction management shows equal results on written test scores but improved performance during a high-fidelity severe contrast reaction simulation scenario.

High-Fidelity Simulation Meets Athletic Training Education: An Innovative Collaborative Teaching Project

ERIC Educational Resources Information Center

Palmer, Elizabeth; Edwards, Taylor; Racchini, James

2014-01-01

High-fidelity simulation is frequently used in nursing education to provide students with simulated experiences prior to and throughout clinical coursework that involves direct patient care. These high-tech exercises take advantage of the benefits of a standardized patient or mock patient encounter, while eliminating some of the drawbacks…

High fidelity quantum teleportation assistance with quantum neural network

NASA Astrophysics Data System (ADS)

Huang, Chunhui; Wu, Bichun

2014-09-01

In this paper, a high fidelity scheme of quantum teleportation based on quantum neural network (QNN) is proposed. The QNN is composed of multi-bit control-not gates. The quantum teleportation of a qubit state via two-qubit entangled channels is investigated by solving the master equation in Lindblad operators with a noisy environment. To ensure the security of quantum teleportation, the indirect training of QNN is employed. Only 10% of teleported information is extracted for the training of QNN parameters. Then the outputs are corrected by the other QNN at Bob's side. We build a random series of numbers ranged in [0, π] as inputs and simulate the properties of our teleportation scheme. The results show that the fidelity of quantum teleportation system is significantly improved to approach 1 by the error-correction of QNN. It illustrates that the distortion can be eliminated perfectly and the high fidelity of quantum teleportation could be implemented.

High-fidelity quantum gates on quantum-dot-confined electron spins in low-Q optical microcavities

NASA Astrophysics Data System (ADS)

Li, Tao; Gao, Jian-Cun; Deng, Fu-Guo; Long, Gui-Lu

2018-04-01

We propose some high-fidelity quantum circuits for quantum computing on electron spins of quantum dots (QD) embedded in low-Q optical microcavities, including the two-qubit controlled-NOT gate and the multiple-target-qubit controlled-NOT gate. The fidelities of both quantum gates can, in principle, be robust to imperfections involved in a practical input-output process of a single photon by converting the infidelity into a heralded error. Furthermore, the influence of two different decay channels is detailed. By decreasing the quality factor of the present microcavity, we can largely increase the efficiencies of these quantum gates while their high fidelities remain unaffected. This proposal also has another advantage regarding its experimental feasibility, in that both quantum gates can work faithfully even when the QD-cavity systems are non-identical, which is of particular importance in current semiconductor QD technology.

Design Considerations for Attitude State Awareness and Prevention of Entry into Unusual Attitudes

NASA Technical Reports Server (NTRS)

Ellis, Kyle K. E.; Prinzel, Lawrence J., III; Arthur, Jarvis J.; Nicholas, Stephanie N.; Kiggins, Daniel; Verstynen, Harry; Hubbs, Clay; Wilkerson, James

2017-01-01

Loss of control - inflight (LOC-I) has historically represented the largest category of commercial aviation fatal accidents. A review of the worldwide transport airplane accidents (2001-2010) evinced that loss of attitude or energy state awareness was responsible for a large majority of the LOC-I events. A Commercial Aviation Safety Team (CAST) study of 18 worldwide loss-of-control accidents and incidents determined that flight crew loss of attitude awareness or energy state awareness due to lack of external visual reference cues was a significant causal factor in 17 of the 18 reviewed flights. CAST recommended that "Virtual Day-Visual Meteorological Condition" (Virtual Day-VMC) displays be developed to provide the visual cues necessary to prevent loss-of-control resulting from flight crew spatial disorientation and loss of energy state awareness. Synthetic vision or equivalent systems (SVS) were identified for a design "safety enhancement" (SE-200). Part of this SE involves the conduct of research for developing minimum aviation system performance standards (MASPS) for these flight deck display technologies to aid flight crew attitude and energy state awareness similar to that of a virtual day-VMC-like environment. This paper will describe a novel experimental approach to evaluating a flight crew's ability to maintain attitude awareness and to prevent entry into unusual attitudes across several SVS optical flow design considerations. Flight crews were subjected to compound-event scenarios designed to elicit channelized attention and startle/surprise within the crew. These high-fidelity scenarios, designed from real-world events, enable evaluation of the efficacy of SVS at improving flight crew attitude awareness to reduce the occurrence of LOC-I incidents in commercial flight operations.

Virtual presence for mission visualization: computer game technology provides a new approach

NASA Astrophysics Data System (ADS)

Hussey, K.

2007-08-01

The concept of virtual presence for mission and planetary science visualization is to allow the public to "see" in space as if they were either riding aboard or standing next to an ESA/NASA spacecraft. Our approach to accomplishing this goal is to utilize and extend the same technology used by the computer gaming industry.With this technology, people would be able to immediately "look" in any direction from their virtual location and "zoom-in" at will. Whenever real data for their "view" exists it would be incorporated into the scene. Where data is missing, a high-fidelity simulation of the view would be generated to fill in the chosen field of view. The observer could also change the time of observation into the past or future. The potential for the application of this technology for the development of educational curricula is huge. On the engineering side, all allowable spacecraft and environmental parameters that are being measured and sent to Earth would be immediately viewable as if looking at the dashboard of a car or an instrument panel of an aircraft. Historical information could also be displayed upon request. This can revolutionize the way the general public and planetary scientific community views ESA/NASA missions and provides an educational context that is attractive to the younger generation. While conceptually using this technology is quite simple, the cross-discipline technical challenges are very demanding. This technology is currently under development and application at JPL to assist current missions in viewing their data, communicating with the public and visualizing future mission plans. Real-time demonstrations of the technology described will be shown.

Site fidelity, mate fidelity, and breeding dispersal in American kestrels

USGS Publications Warehouse

Steenhof, K.; Peterson, B.E.

2009-01-01

We assessed mate fidelity, nest-box fidelity, and breeding dispersal distances of American Kestrels (falco sparverius) nesting in boxes in southwestern Idaho from 1990 through 2006. Seventy-seven percent of boxes had different males and 87% had different females where nest-box occupants were identified in consecutive years. High turnover rates were partly a result of box-switching. Forty-eight percent of males and 58% of females that nested within the study area in successive years used different boxes. The probability of changing boxes was unrelated to gender, nesting success in the prior year, or years of nesting experience. Breeding dispersal distances for birds that moved to different boxes averaged 2.2 km for males (max = 22 km) and 3.2 km for females (max = 32 km). Approximately 70% of birds that nested in consecutive years on the study area had a different mate in the second year. Mate fidelity was related to box fidelity but not to prior nesting success or years of nesting experience. Mate changes occurred 32% of the time when the previous mate was known to be alive and nesting in the area. Kestrels that switched mates and boxes did not improve or decrease their subsequent nesting success. Kestrels usually switched to mates with less experience and lower lifetime productivity than their previous mates. The costs of switching boxes and mates were low, and there were no obvious benefits to fidelity. The cost of "waiting" for a previous mate that might have died could be high in species with high annual mortality.

Training for shoulder dystocia: a trial of simulation using low-fidelity and high-fidelity mannequins.

PubMed

Crofts, Joanna F; Bartlett, Christine; Ellis, Denise; Hunt, Linda P; Fox, Robert; Draycott, Timothy J

2006-12-01

To evaluate the effectiveness of simulation training for shoulder dystocia management and compare training using a high-fidelity mannequin with that using traditional devices. Training was undertaken in six hospitals and a medical simulation center in the United Kingdom. Midwives and obstetricians working for participating hospitals were eligible for inclusion. One hundred forty participants (45 doctors, 95 midwives) were randomized to training with a high-fidelity training mannequin (incorporating force perception training) or traditional low-fidelity mannequins. Performance was assessed pre- and posttraining, using a videoed, standardized shoulder dystocia simulation. Outcome measures were delivery, head-to-body delivery time, use of appropriate and inappropriate actions, force applied, and communication. One hundred thirty-two participants completed the posttraining assessment. All training was associated with improved performance: use of basic maneuvers 114 of 140 (81.4%) to 125 of 132 (94.7%) (P=.002), successful deliveries 60 of 140 (42.9%) to 110 of 132 (83.3%) (P<.001), good communication with the patient 79 of 139 (56.8%) to 109 of 132 (82.6%) (P<.001), pre- and posttraining, respectively. Training with the high-fidelity mannequin was associated with a higher successful delivery rate than training with traditional devices: 94% compared with 72% (odds ratio 6.53, 95% confidence interval 2.05-20.81; P=.002). Total applied force was significantly lower for those who had undergone force training (2,030 Newton seconds versus 2,916 Newton seconds; P=.006) but there was no significant difference in the peak applied force 102 Newtons versus 112 Newtons (P=.242). This study verifies the need for shoulder dystocia training; before training only 43% participants could achieve delivery. All training with mannequins improved the management of simulated shoulder dystocia. Training on a high-fidelity mannequin, including force perception teaching, offered additional training benefits. I.

Progress in the Utilization of High-Fidelity Simulation in Basic Science Education

ERIC Educational Resources Information Center

Helyer, Richard; Dickens, Peter

2016-01-01

High-fidelity patient simulators are mainly used to teach clinical skills and remain underutilized in teaching basic sciences. This article summarizes our current views on the use of simulation in basic science education and identifies pitfalls and opportunities for progress.

GIS Data Based Automatic High-Fidelity 3D Road Network Modeling

NASA Technical Reports Server (NTRS)

Wang, Jie; Shen, Yuzhong

2011-01-01

3D road models are widely used in many computer applications such as racing games and driving simulations_ However, almost all high-fidelity 3D road models were generated manually by professional artists at the expense of intensive labor. There are very few existing methods for automatically generating 3D high-fidelity road networks, especially those existing in the real world. This paper presents a novel approach thai can automatically produce 3D high-fidelity road network models from real 2D road GIS data that mainly contain road. centerline in formation. The proposed method first builds parametric representations of the road centerlines through segmentation and fitting . A basic set of civil engineering rules (e.g., cross slope, superelevation, grade) for road design are then selected in order to generate realistic road surfaces in compliance with these rules. While the proposed method applies to any types of roads, this paper mainly addresses automatic generation of complex traffic interchanges and intersections which are the most sophisticated elements in the road networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zitney, S.E.; McCorkle, D.; Yang, C.

Process modeling and simulation tools are widely used for the design and operation of advanced power generation systems. These tools enable engineers to solve the critical process systems engineering problems that arise throughout the lifecycle of a power plant, such as designing a new process, troubleshooting a process unit or optimizing operations of the full process. To analyze the impact of complex thermal and fluid flow phenomena on overall power plant performance, the Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) has developed the Advanced Process Engineering Co-Simulator (APECS). The APECS system is an integrated software suite that combinesmore » process simulation (e.g., Aspen Plus) and high-fidelity equipment simulations such as those based on computational fluid dynamics (CFD), together with advanced analysis capabilities including case studies, sensitivity analysis, stochastic simulation for risk/uncertainty analysis, and multi-objective optimization. In this paper we discuss the initial phases of the integration of the APECS system with the immersive and interactive virtual engineering software, VE-Suite, developed at Iowa State University and Ames Laboratory. VE-Suite uses the ActiveX (OLE Automation) controls in the Aspen Plus process simulator wrapped by the CASI library developed by Reaction Engineering International to run process/CFD co-simulations and query for results. This integration represents a necessary step in the development of virtual power plant co-simulations that will ultimately reduce the time, cost, and technical risk of developing advanced power generation systems.« less

Optimal visual simulation of the self-tracking combustion of the infrared decoy based on the particle system

NASA Astrophysics Data System (ADS)

Hu, Qi; Duan, Jin; Wang, LiNing; Zhai, Di

2016-09-01

The high-efficiency simulation test of military weapons has a very important effect on the high cost of the actual combat test and the very demanding operational efficiency. Especially among the simulative emulation methods of the explosive smoke, the simulation method based on the particle system has generated much attention. In order to further improve the traditional simulative emulation degree of the movement process of the infrared decoy during the real combustion cycle, this paper, adopting the virtual simulation platform of OpenGL and Vega Prime and according to their own radiation characteristics and the aerodynamic characteristics of the infrared decoy, has simulated the dynamic fuzzy characteristics of the infrared decoy during the real combustion cycle by using particle system based on the double depth peeling algorithm and has solved key issues such as the interface, coordinate conversion and the retention and recovery of the Vega Prime's status. The simulation experiment has basically reached the expected improvement purpose, effectively improved the simulation fidelity and provided theoretical support for improving the performance of the infrared decoy.

A fast mass spring model solver for high-resolution elastic objects

NASA Astrophysics Data System (ADS)

Zheng, Mianlun; Yuan, Zhiyong; Zhu, Weixu; Zhang, Guian

2017-03-01

Real-time simulation of elastic objects is of great importance for computer graphics and virtual reality applications. The fast mass spring model solver can achieve visually realistic simulation in an efficient way. Unfortunately, this method suffers from resolution limitations and lack of mechanical realism for a surface geometry model, which greatly restricts its application. To tackle these problems, in this paper we propose a fast mass spring model solver for high-resolution elastic objects. First, we project the complex surface geometry model into a set of uniform grid cells as cages through *cages mean value coordinate method to reflect its internal structure and mechanics properties. Then, we replace the original Cholesky decomposition method in the fast mass spring model solver with a conjugate gradient method, which can make the fast mass spring model solver more efficient for detailed surface geometry models. Finally, we propose a graphics processing unit accelerated parallel algorithm for the conjugate gradient method. Experimental results show that our method can realize efficient deformation simulation of 3D elastic objects with visual reality and physical fidelity, which has a great potential for applications in computer animation.

Hippocampal replay of extended experience

PubMed Central

Davidson, Thomas J.; Kloosterman, Fabian; Wilson, Matthew A.

2009-01-01

Summary During pauses in exploration, ensembles of place cells in the rat hippocampus re-express firing sequences corresponding to recent spatial experience. Such ‘replay’ co-occurs with ripple events: short-lasting (~50–120 ms), high frequency (~200 Hz) oscillations that are associated with increased hippocampal-cortical communication. In previous studies, rats explored small environments, and replay was found to be anchored to the rat’s current location, and compressed in time such that replay of the complete environment occurred during a single ripple event. It is not known whether or how longer behavioral sequences are replayed in the hippocampus. Here we show, using a neural decoding approach, that firing sequences corresponding to long runs through a large environment are replayed with high fidelity (in both forward and reverse order), and that such replay can begin at remote locations on the track. Extended replay proceeds at a characteristic virtual speed of ~8 m/s, and remains coherent across trains of ripple events. These results suggest that extended replay is composed of chains of shorter subsequences, which may reflect a strategy for the storage and flexible expression of memories of prolonged experience. PMID:19709631

Hybrid surrogate-model-based multi-fidelity efficient global optimization applied to helicopter blade design

NASA Astrophysics Data System (ADS)

Ariyarit, Atthaphon; Sugiura, Masahiko; Tanabe, Yasutada; Kanazaki, Masahiro

2018-06-01

A multi-fidelity optimization technique by an efficient global optimization process using a hybrid surrogate model is investigated for solving real-world design problems. The model constructs the local deviation using the kriging method and the global model using a radial basis function. The expected improvement is computed to decide additional samples that can improve the model. The approach was first investigated by solving mathematical test problems. The results were compared with optimization results from an ordinary kriging method and a co-kriging method, and the proposed method produced the best solution. The proposed method was also applied to aerodynamic design optimization of helicopter blades to obtain the maximum blade efficiency. The optimal shape obtained by the proposed method achieved performance almost equivalent to that obtained using the high-fidelity, evaluation-based single-fidelity optimization. Comparing all three methods, the proposed method required the lowest total number of high-fidelity evaluation runs to obtain a converged solution.

Comparison of Intervention Fidelity between COPE TEEN and an Attention-Control Program in a Randomized Controlled Trial

ERIC Educational Resources Information Center

Kelly, Stephanie A.; Oswalt, Krista; Melnyk, Bernadette Mazurek; Jacobson, Diana

2015-01-01

Fidelity in implementing an intervention is critical to accurately determine and interpret the effects of an intervention. It is important to monitor the manner in which the behavioral intervention is implemented (e.g. adaptations, delivery as intended and dose). Few interventions are implemented with 100% fidelity. In this study, high school…

A high-throughput assay for the comprehensive profiling of DNA ligase fidelity

PubMed Central

Lohman, Gregory J. S.; Bauer, Robert J.; Nichols, Nicole M.; Mazzola, Laurie; Bybee, Joanna; Rivizzigno, Danielle; Cantin, Elizabeth; Evans, Thomas C.

2016-01-01

DNA ligases have broad application in molecular biology, from traditional cloning methods to modern synthetic biology and molecular diagnostics protocols. Ligation-based detection of polynucleotide sequences can be achieved by the ligation of probe oligonucleotides when annealed to a complementary target sequence. In order to achieve a high sensitivity and low background, the ligase must efficiently join correctly base-paired substrates, while discriminating against the ligation of substrates containing even one mismatched base pair. In the current study, we report the use of capillary electrophoresis to rapidly generate mismatch fidelity profiles that interrogate all 256 possible base-pair combinations at a ligation junction in a single experiment. Rapid screening of ligase fidelity in a 96-well plate format has allowed the study of ligase fidelity in unprecedented depth. As an example of this new method, herein we report the ligation fidelity of Thermus thermophilus DNA ligase at a range of temperatures, buffer pH and monovalent cation strength. This screen allows the selection of reaction conditions that maximize fidelity without sacrificing activity, while generating a profile of specific mismatches that ligate detectably under each set of conditions. PMID:26365241

A high-throughput assay for the comprehensive profiling of DNA ligase fidelity.

PubMed

Lohman, Gregory J S; Bauer, Robert J; Nichols, Nicole M; Mazzola, Laurie; Bybee, Joanna; Rivizzigno, Danielle; Cantin, Elizabeth; Evans, Thomas C

2016-01-29

DNA ligases have broad application in molecular biology, from traditional cloning methods to modern synthetic biology and molecular diagnostics protocols. Ligation-based detection of polynucleotide sequences can be achieved by the ligation of probe oligonucleotides when annealed to a complementary target sequence. In order to achieve a high sensitivity and low background, the ligase must efficiently join correctly base-paired substrates, while discriminating against the ligation of substrates containing even one mismatched base pair. In the current study, we report the use of capillary electrophoresis to rapidly generate mismatch fidelity profiles that interrogate all 256 possible base-pair combinations at a ligation junction in a single experiment. Rapid screening of ligase fidelity in a 96-well plate format has allowed the study of ligase fidelity in unprecedented depth. As an example of this new method, herein we report the ligation fidelity of Thermus thermophilus DNA ligase at a range of temperatures, buffer pH and monovalent cation strength. This screen allows the selection of reaction conditions that maximize fidelity without sacrificing activity, while generating a profile of specific mismatches that ligate detectably under each set of conditions. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Spawning site fidelity of wild and hatchery lake trout (Salvelinus namaycush) in northern Lake Huron

USGS Publications Warehouse

Binder, Thomas; Riley, Stephen C.; Holbrook, Christopher; Hansen, Michael J.; Bergstedt, Roger A.; Bronte, Charles R.; He, Ji; Krueger, Charles C.

2016-01-01

Fidelity to high-quality spawning sites helps ensure that adults repeatedly spawn at sites that maximize reproductive success. Fidelity is also an important behavioural characteristic to consider when hatchery-reared individuals are stocked for species restoration, because artificial rearing environments may interfere with cues that guide appropriate spawning site selection. Acoustic telemetry was used in conjunction with Cormack–Jolly–Seber capture–recapture models to compare degree of spawning site fidelity of wild and hatchery-reared lake trout (Salvelinus namaycush) in northern Lake Huron. Annual survival was estimated to be between 77% and 81% and did not differ among wild and hatchery males and females. Site fidelity estimates were high in both wild and hatchery-reared lake trout (ranging from 0.78 to 0.94, depending on group and time filter), but were slightly lower in hatchery-reared fish than in wild fish. The ecological implication of the small difference in site fidelity between wild and hatchery-reared lake trout is unclear, but similarities in estimates suggest that many hatchery-reared fish use similar spawning sites to wild fish and that most return to those sites annually for spawning.

High-fidelity readout in circuit quantum electrodynamics using the Jaynes-Cummings nonlinearity.

PubMed

Reed, M D; DiCarlo, L; Johnson, B R; Sun, L; Schuster, D I; Frunzio, L; Schoelkopf, R J

2010-10-22

We demonstrate a qubit readout scheme that exploits the Jaynes-Cummings nonlinearity of a superconducting cavity coupled to transmon qubits. We find that, in the strongly driven dispersive regime of this system, there is the unexpected onset of a high-transmission "bright" state at a critical power which depends sensitively on the initial qubit state. A simple and robust measurement protocol exploiting this effect achieves a single-shot fidelity of 87% using a conventional sample design and experimental setup, and at least 61% fidelity to joint correlations of three qubits.

EBUS-STAT Subscore Analysis to Predict the Efficacy and Assess the Validity of Virtual Reality Simulation for EBUS-TBNA Training Among Experienced Bronchoscopists.

PubMed

Scarlata, Simone; Palermo, Patrizio; Candoli, Piero; Tofani, Ariela; Petitti, Tommasangelo; Corbetta, Lorenzo

2017-04-01

Linear endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) represents a pivotal innovation in interventional pulmonology; determining the best approach to guarantee systematic and efficient training is expected to become a main issue in the forthcoming years. Virtual reality simulators have been proposed as potential EBUS-TBNA training instruments, to avoid unskilled beginners practicing directly in real-life settings. A validated and perfected simulation program could be used before allowing beginners to practice on patients. Our goal was to test the reliability of the EBUS-Skills and Task Assessment Tool (STAT) and its subscores for measuring the competence of experienced bronchoscopists approaching EBUS-guided TBNA, using only the virtual reality simulator as both a training and an assessment tool. Fifteen experienced bronchoscopists, with poor or no experience in EBUS-TBNA, participated in this study. They were all administered the Italian version of the EBUS-STAT evaluation tool, during a high-fidelity virtual reality simulation. This was followed by a single 7-hour theoretical and practical (on simulators) session on EBUS-TBNA, at the end of which their skills were reassessed by EBUS-STAT. An overall, significant improvement in EBUS-TBNA skills was observed, thereby confirming that (a) virtual reality simulation can facilitate practical learning among practitioners, and (b) EBUS-STAT is capable of detecting these improvements. The test's overall ability to detect differences was negatively influenced by the minimal variation of the scores relating to items 1 and 2, was not influenced by the training, and improved significantly when the 2 items were not considered. Apart from these 2 items, all the remaining subscores were equally capable of revealing improvements in the learner. Lastly, we found that trainees with presimulation EBUS-STAT scores above 79 did not show any significant improvement after virtual reality training, suggesting that this score represents a cutoff value capable of predicting the likelihood that simulation can be beneficial. Virtual reality simulation is capable of providing a practical learning tool for practitioners with previous experience in flexible bronchoscopy, and the EBUS-STAT questionnaire is capable of detecting these changes. A pretraining EBUS-STAT score below 79 is a good indicator of those candidates who will benefit from the simulation training. Further studies are needed to verify whether a modified version of the questionnaire would be capable of improving its performance among experienced bronchoscopists.

Experimental test of fidelity limits in six-photon interferometry and of rotational invariance properties of the photonic six-qubit entanglement singlet state.

PubMed

Rådmark, Magnus; Zukowski, Marek; Bourennane, Mohamed

2009-10-09

Quantum multiphoton interferometry has now reached the six-photon stage. Thus far, the observed fidelities of entangled states never reached 2/3. We report a high fidelity (estimated at 88%) experiment in which six-qubit singlet correlations were observed. With such a high fidelity we are able to demonstrate the central property of these "singlet" correlations, their "rotational invariance," by performing a full set of measurements in three complementary polarization bases. The patterns are almost indistinguishable. The data reveal genuine six-photon entanglement. We also study several five-photon states, which result upon detection of one of the photons. Multiphoton singlet states survive some types of depolarization and are thus important in quantum communication schemes.

Multiple displacement amplification in combination with high-fidelity PCR improves detection of bacteria from single females or eggs of Metaseiulus occidentalis (Nesbitt) (Acari: Phytoseiidae).

PubMed

Jeyaprakash, Ayyamperumal; Hoy, Marjorie A

2004-07-01

Amplifying microbial DNA by the polymerase chain reaction (PCR) from single phytoseiid mites has been difficult, perhaps due to the low titer of bacteria and to interference by the relatively larger amounts of mite genomic DNA. In this paper we evaluate the efficiency of standard and high-fidelity PCR protocols subsequent to amplification of the whole genome by a multiple displacement amplification (MDA) procedure developed by Dean et al. DNA from the phytoseiid Phytoseiulus persimilis (Athias-Henriot) was tested because it lacks a Cytophaga-like organism (CLO) and we could add known amounts of a plasmid containing a cloned 16S rRNA gene fragment from a CLO from Metaseiulus occidentalis (Nesbitt). P. persimilis genomic DNA was mixed with the serially diluted plasmid and amplified using MDA followed by either standard or high-fidelity PCR. MDA followed by high-fidelity PCR was most efficient and successfully amplified an expected 1.5-kb band from as little as 0.01fg of the plasmid, which is equivalent to about 1 copy. MDA followed by high-fidelity PCR also consistently amplified Wolbachia- or CLO-specific products from naturally infected single females or eggs of M. occidentalis, which will allow detailed studies of infection frequency and transmission of several microorganisms associated with this predatory mite.

Degrees of reality: airway anatomy of high-fidelity human patient simulators and airway trainers.

PubMed

Schebesta, Karl; Hüpfl, Michael; Rössler, Bernhard; Ringl, Helmut; Müller, Michael P; Kimberger, Oliver

2012-06-01

Human patient simulators and airway training manikins are widely used to train airway management skills to medical professionals. Furthermore, these patient simulators are employed as standardized "patients" to evaluate airway devices. However, little is known about how realistic these patient simulators and airway-training manikins really are. This trial aimed to evaluate the upper airway anatomy of four high-fidelity patient simulators and two airway trainers in comparison with actual patients by means of radiographic measurements. The volume of the pharyngeal airspace was the primary outcome parameter. Computed tomography scans of 20 adult trauma patients without head or neck injuries were compared with computed tomography scans of four high-fidelity patient simulators and two airway trainers. By using 14 predefined distances, two cross-sectional areas and three volume parameters of the upper airway, the manikins' similarity to a human patient was assessed. The pharyngeal airspace of all manikins differed significantly from the patients' pharyngeal airspace. The HPS Human Patient Simulator (METI®, Sarasota, FL) was the most realistic high-fidelity patient simulator (6/19 [32%] of all parameters were within the 95% CI of human airway measurements). The airway anatomy of four high-fidelity patient simulators and two airway trainers does not reflect the upper airway anatomy of actual patients. This finding may impact airway training and confound comparative airway device studies.

Simulation-based Education for Endoscopic Third Ventriculostomy: A Comparison Between Virtual and Physical Training Models.

PubMed

Breimer, Gerben E; Haji, Faizal A; Bodani, Vivek; Cunningham, Melissa S; Lopez-Rios, Adriana-Lucia; Okrainec, Allan; Drake, James M

2017-02-01

The relative educational benefits of virtual reality (VR) and physical simulation models for endoscopic third ventriculostomy (ETV) have not been evaluated "head to head." To compare and identify the relative utility of a physical and VR ETV simulation model for use in neurosurgical training. Twenty-three neurosurgical residents and 3 fellows performed an ETV on both a physical and VR simulation model. Trainees rated the models using 5-point Likert scales evaluating the domains of anatomy, instrument handling, procedural content, and the overall fidelity of the simulation. Paired t tests were performed for each domain's mean overall score and individual items. The VR model has relative benefits compared with the physical model with respect to realistic representation of intraventricular anatomy at the foramen of Monro (4.5, standard deviation [SD] = 0.7 vs 4.1, SD = 0.6; P = .04) and the third ventricle floor (4.4, SD = 0.6 vs 4.0, SD = 0.9; P = .03), although the overall anatomy score was similar (4.2, SD = 0.6 vs 4.0, SD = 0.6; P = .11). For overall instrument handling and procedural content, the physical simulator outperformed the VR model (3.7, SD = 0.8 vs 4.5; SD = 0.5, P < .001 and 3.9; SD = 0.8 vs 4.2, SD = 0.6; P = .02, respectively). Overall task fidelity across the 2 simulators was not perceived as significantly different. Simulation model selection should be based on educational objectives. Training focused on learning anatomy or decision-making for anatomic cues may be aided with the VR simulation model. A focus on developing manual dexterity and technical skills using endoscopic equipment in the operating room may be better learned on the physical simulation model. Copyright © 2016 by the Congress of Neurological Surgeons

Using virtual worlds for role play simulation in child and adolescent psychiatry: an evaluation study

PubMed Central

Vallance, Aaron K.; Hemani, Ashish; Fernandez, Victoria; Livingstone, Daniel; McCusker, Kerri; Toro-Troconis, Maria

2014-01-01

Aims and method To develop and evaluate a novel teaching session on clinical assessment using role play simulation. Teaching and research sessions occurred sequentially in computer laboratories. Ten medical students were divided into two online small-group teaching sessions. Students role-played as clinician avatars and the teacher played a suicidal adolescent avatar. Questionnaire and focus-group methodology evaluated participants’ attitudes to the learning experience. Quantitative data were analysed using SPSS, qualitative data through nominal-group and thematic analyses. Results Participants reported improvements in psychiatric skills/knowledge, expressing less anxiety and more enjoyment than role-playing face to face. Data demonstrated a positive relationship between simulator fidelity and perceived utility. Some participants expressed concern about added value over other learning methods and non-verbal communication. Clinical implications The study shows that virtual worlds can successfully host role play simulation, valued by students as a useful learning method. The potential for distance learning would allow delivery irrespective of geographical distance and boundaries. PMID:25285217

A weighted variational gradient-based fusion method for high-fidelity thin cloud removal of Landsat images

NASA Astrophysics Data System (ADS)

Huang, Wei; Chen, Xiu; Wang, Yueyun

2018-03-01

Landsat data are widely used in various earth observations, but the clouds interfere with the applications of the images. This paper proposes a weighted variational gradient-based fusion method (WVGBF) for high-fidelity thin cloud removal of Landsat images, which is an improvement of the variational gradient-based fusion (VGBF) method. The VGBF method integrates the gradient information from the reference band into visible bands of cloudy image to enable spatial details and remove thin clouds. The VGBF method utilizes the same gradient constraints to the entire image, which causes the color distortion in cloudless areas. In our method, a weight coefficient is introduced into the gradient approximation term to ensure the fidelity of image. The distribution of weight coefficient is related to the cloud thickness map. The map is built on Independence Component Analysis (ICA) by using multi-temporal Landsat images. Quantitatively, we use R value to evaluate the fidelity in the cloudless regions and metric Q to evaluate the clarity in the cloud areas. The experimental results indicate that the proposed method has the better ability to remove thin cloud and achieve high fidelity.

Development and validation of the ASPIRE-VA coaching fidelity checklist (ACFC): a tool to help ensure delivery of high-quality weight management interventions.

PubMed

Damschroder, Laura J; Goodrich, David E; Kim, Hyungjin Myra; Holleman, Robert; Gillon, Leah; Kirsh, Susan; Richardson, Caroline R; Lutes, Lesley D

2016-09-01

Practical and valid instruments are needed to assess fidelity of coaching for weight loss. The purpose of this study was to develop and validate the ASPIRE Coaching Fidelity Checklist (ACFC). Classical test theory guided ACFC development. Principal component analyses were used to determine item groupings. Psychometric properties, internal consistency, and inter-rater reliability were evaluated for each subscale. Criterion validity was tested by predicting weight loss as a function of coaching fidelity. The final 19-item ACFC consists of two domains (session process and session structure) and five subscales (sets goals and monitor progress, assess and personalize self-regulatory content, manages the session, creates a supportive and empathetic climate, and stays on track). Four of five subscales showed high internal consistency (Cronbach alphas > 0.70) for group-based coaching; only two of five subscales had high internal reliability for phone-based coaching. All five sub-scales were positively and significantly associated with weight loss for group- but not for phone-based coaching. The ACFC is a reliable and valid instrument that can be used to assess fidelity and guide skill-building for weight management interventionists.

High-Fidelity Multidisciplinary Design Optimization of Aircraft Configurations

NASA Technical Reports Server (NTRS)

Martins, Joaquim R. R. A.; Kenway, Gaetan K. W.; Burdette, David; Jonsson, Eirikur; Kennedy, Graeme J.

2017-01-01

To evaluate new airframe technologies we need design tools based on high-fidelity models that consider multidisciplinary interactions early in the design process. The overarching goal of this NRA is to develop tools that enable high-fidelity multidisciplinary design optimization of aircraft configurations, and to apply these tools to the design of high aspect ratio flexible wings. We develop a geometry engine that is capable of quickly generating conventional and unconventional aircraft configurations including the internal structure. This geometry engine features adjoint derivative computation for efficient gradient-based optimization. We also added overset capability to a computational fluid dynamics solver, complete with an adjoint implementation and semiautomatic mesh generation. We also developed an approach to constraining buffet and started the development of an approach for constraining utter. On the applications side, we developed a new common high-fidelity model for aeroelastic studies of high aspect ratio wings. We performed optimal design trade-o s between fuel burn and aircraft weight for metal, conventional composite, and carbon nanotube composite wings. We also assessed a continuous morphing trailing edge technology applied to high aspect ratio wings. This research resulted in the publication of 26 manuscripts so far, and the developed methodologies were used in two other NRAs. 1

Graphic and haptic simulation for transvaginal cholecystectomy training in NOTES.

PubMed

Pan, Jun J; Ahn, Woojin; Dargar, Saurabh; Halic, Tansel; Li, Bai C; Sankaranarayanan, Ganesh; Roberts, Kurt; Schwaitzberg, Steven; De, Suvranu

2016-04-01

Natural Orifice Transluminal Endoscopic Surgery (NOTES) provides an emerging surgical technique which usually needs a long learning curve for surgeons. Virtual reality (VR) medical simulators with vision and haptic feedback can usually offer an efficient and cost-effective alternative without risk to the traditional training approaches. Under this motivation, we developed the first virtual reality simulator for transvaginal cholecystectomy in NOTES (VTEST™). This VR-based surgical simulator aims to simulate the hybrid NOTES of cholecystectomy. We use a 6DOF haptic device and a tracking sensor to construct the core hardware component of simulator. For software, an innovative approach based on the inner-spheres is presented to deform the organs in real time. To handle the frequent collision between soft tissue and surgical instruments, an adaptive collision detection method based on GPU is designed and implemented. To give a realistic visual performance of gallbladder fat tissue removal by cautery hook, a multi-layer hexahedral model is presented to simulate the electric dissection of fat tissue. From the experimental results, trainees can operate in real time with high degree of stability and fidelity. A preliminary study was also performed to evaluate the realism and the usefulness of this hybrid NOTES simulator. This prototyped simulation system has been verified by surgeons through a pilot study. Some items of its visual performance and the utility were rated fairly high by the participants during testing. It exhibits the potential to improve the surgical skills of trainee and effectively shorten their learning curve. Copyright © 2016 Elsevier Inc. All rights reserved.

Competency: Does High Fidelity Simulation Make a Difference?

ERIC Educational Resources Information Center

Valente, Alice M.

2010-01-01

High fidelity simulation is a well documented adjunctive teaching method in medical and nurse practitioner programs, but few studies of effectiveness on this technology on the development of competency have emphasized pre-licensure associate degree level programs. This study explored student competency in the application of the nursing process…

Using nonfaculty registered nurses to facilitate high-fidelity human patient simulation activities.

PubMed

Foster, Janet G; Sheriff, Susan; Cheney, Susan

2008-01-01

Maximizing faculty resources using nonfaculty registered nurses to supervise high-fidelity human-patient simulation is an innovative strategy for addressing the nursing faculty shortage and preparing graduates to practice safely in hospitals. The authors describe their use of nonfaculty registered nurses and its outcomes.

Tidal Energy Resource Assessment for McMurdo Station, Antarctica

DTIC Science & Technology

2016-12-01

highest power coefficient possible, only to provide a high- fidelity data set for a simple geometry turbine model at reasonably high blade chord Reynolds...highest power coefficient possible, only to provide a high-fidelity data set for a simple geometry turbine model at reasonably high blade chord...Reynolds numbers. Tip speed ratio, , is defined as = where is the anglular velocity of the blade and is the

Web-Based versus High-Fidelity Simulation Training for Certified Registered Nurse Anesthetists in the Management of High Risk/Low Occurrence Anesthesia Events

ERIC Educational Resources Information Center

Kimemia, Judy

2017-01-01

Purpose: The purpose of this project was to compare web-based to high-fidelity simulation training in the management of high risk/low occurrence anesthesia related events, to enhance knowledge acquisition for Certified Registered Nurse Anesthetists (CRNAs). This project was designed to answer the question: Is web-based training as effective as…

CTF (Subchannel) Calculations and Validation L3:VVI.H2L.P15.01

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gordon, Natalie

The goal of the Verification and Validation Implementation (VVI) High to Low (Hi2Lo) process is utilizing a validated model in a high resolution code to generate synthetic data for improvement of the same model in a lower resolution code. This process is useful in circumstances where experimental data does not exist or it is not sufficient in quantity or resolution. Data from the high-fidelity code is treated as calibration data (with appropriate uncertainties and error bounds) which can be used to train parameters that affect solution accuracy in the lower-fidelity code model, thereby reducing uncertainty. This milestone presents a demonstrationmore » of the Hi2Lo process derived in the VVI focus area. The majority of the work performed herein describes the steps of the low-fidelity code used in the process with references to the work detailed in the companion high-fidelity code milestone (Reference 1). The CASL low-fidelity code used to perform this work was Cobra Thermal Fluid (CTF) and the high-fidelity code was STAR-CCM+ (STAR). The master branch version of CTF (pulled May 5, 2017 – Reference 2) was utilized for all CTF analyses performed as part of this milestone. The statistical and VVUQ components of the Hi2Lo framework were performed using Dakota version 6.6 (release date May 15, 2017 – Reference 3). Experimental data from Westinghouse Electric Company (WEC – Reference 4) was used throughout the demonstrated process to compare with the high-fidelity STAR results. A CTF parameter called Beta was chosen as the calibration parameter for this work. By default, Beta is defined as a constant mixing coefficient in CTF and is essentially a tuning parameter for mixing between subchannels. Since CTF does not have turbulence models like STAR, Beta is the parameter that performs the most similar function to the turbulence models in STAR. The purpose of the work performed in this milestone is to tune Beta to an optimal value that brings the CTF results closer to those measured in the WEC experiments.« less

Microstructure Modeling of 3rd Generation Disk Alloy

NASA Technical Reports Server (NTRS)

Jou, Herng-Jeng

2008-01-01

The objective of this initiative, funded by NASA's Aviation Safety Program, is to model, validate, and predict, with high fidelity, the microstructural evolution of third-generation high-refractory Ni-based disc superalloys during heat treating and service conditions. This initiative is a natural extension of the DARPA-AIM (Accelerated Insertion of Materials) initiative with GE/Pratt-Whitney and with other process simulation tools. Strong collaboration with the NASA Glenn Research Center (GRC) is a key component of this initiative and the focus of this program is on industrially relevant disk alloys and heat treatment processes identified by GRC. Employing QuesTek s Computational Materials Dynamics technology and PrecipiCalc precipitation simulator, physics-based models are being used to achieve high predictive accuracy and precision. Combining these models with experimental data and probabilistic analysis, "virtual alloy design" can be performed. The predicted microstructures can be optimized to promote desirable features and concurrently eliminate nondesirable phases that can limit the reliability and durability of the alloys. The well-calibrated and well-integrated software tools that are being applied under the proposed program will help gas turbine disk alloy manufacturers, processing facilities, and NASA, to efficiently and effectively improve the performance of current and future disk materials.

Evaluation of Intervention Fidelity in a Multisite Clinical Trial in Persons With Multiple Sclerosis.

PubMed

Morrison, Janet D; Becker, Heather; Stuifbergen, Alexa K

2017-12-01

Careful consideration of intervention fidelity is critical to establishing the validity and reliability of research findings, yet such reports are often lacking in the research literature. It is imperative that intervention fidelity be methodically evaluated and reported to promote the translation of effective interventions into sound evidence-based practice. The purpose of this article is to explore strategies used to promote intervention fidelity, incorporating examples from a multisite clinical trial, that illustrate the National Institutes of Health Behavior Change Consortium's 5 domains for recommended treatment practices: (1) study design, (2) facilitator training, (3) intervention delivery, (4) intervention receipt, and (5) intervention enactment. A multisite randomized clinical trial testing the efficacy of a computer-assisted cognitive rehabilitation intervention for adults with multiple sclerosis is used to illustrate strategies promoting intervention fidelity. Data derived from audiotapes of intervention classes, audits of computer exercises completed by participants, participant class attendance, and goal attainment scaling suggested relatively high fidelity to the intervention protocol. This study illustrates how to report intervention fidelity in the literature guided by best practice strategies, which may serve to promote fidelity monitoring and reporting in future studies.

RNA polymerase II transcriptional fidelity control and its functional interplay with DNA modifications

PubMed Central

Xu, Liang; Wang, Wei; Chong, Jenny; Shin, Ji Hyun; Xu, Jun; Wang, Dong

2016-01-01

Accurate genetic information transfer is essential for life. As a key enzyme involved in the first step of gene expression, RNA polymerase II (Pol II) must maintain high transcriptional fidelity while it reads along DNA template and synthesizes RNA transcript in a stepwise manner during transcription elongation. DNA lesions or modifications may lead to significant changes in transcriptional fidelity or transcription elongation dynamics. In this review, we will summarize recent progress towards understanding the molecular basis of RNA Pol II transcriptional fidelity control and impacts of DNA lesions and modifications on Pol II transcription elongation. PMID:26392149

High fidelity simulations of infrared imagery with animated characters

NASA Astrophysics Data System (ADS)

Näsström, F.; Persson, A.; Bergström, D.; Berggren, J.; Hedström, J.; Allvar, J.; Karlsson, M.

2012-06-01

High fidelity simulations of IR signatures and imagery tend to be slow and do not have effective support for animation of characters. Simplified rendering methods based on computer graphics methods can be used to overcome these limitations. This paper presents a method to combine these tools and produce simulated high fidelity thermal IR data of animated people in terrain. Infrared signatures for human characters have been calculated using RadThermIR. To handle multiple character models, these calculations use a simplified material model for the anatomy and clothing. Weather and temperature conditions match the IR-texture used in the terrain model. The calculated signatures are applied to the animated 3D characters that, together with the terrain model, are used to produce high fidelity IR imagery of people or crowds. For high level animation control and crowd simulations, HLAS (High Level Animation System) has been developed. There are tools available to create and visualize skeleton based animations, but tools that allow control of the animated characters on a higher level, e.g. for crowd simulation, are usually expensive and closed source. We need the flexibility of HLAS to add animation into an HLA enabled sensor system simulation framework.

Developing an instrument for assessing fidelity of motivational care planning: The Aboriginal and Islander Mental health initiative adherence scale.

PubMed

Prowse, Phuong-Tu; Nagel, Tricia

2014-01-01

The aim of this study was to design and trial an Adherence Scale to measure fidelity of Motivational Care Planning (MCP) within a clinical trial. This culturally adapted therapy MCP uses a client centered holistic approach that emphasises family and culture to motivate healthy life style changes. The Motivational Care Planning-Adherence Scale (MCP-AS) was developed through consultation with Aboriginal and Islander Mental Health Initiative (AIMhi) Indigenous and non-Indigenous trainers, and review of MCP training resources. The resultant ten-item scale incorporates a 9-Point Likert Scale with a supporting protocol manual and uses objective, behaviourally anchored criteria for each scale point. A fidelity assessor piloted the tool through analysis of four audio-recordings of MCP (conducted by Indigenous researchers within a study in remote communities in Northern Australia). File audits of the remote therapy sessions were utilised as an additional source of information. A Gold Standard Motivational Care Planning training video was also assessed using the MCP-AS. The Motivational Care Planning-Adherence Scale contains items measuring both process and content of therapy sessions. This scale was used successfully to assess therapy through observation of audio or video-recorded sessions and review of clinical notes. Treatment fidelity measured by the MCP-AS within the pilot study indicated high fidelity ratings. Ratings were high across the three domains of rapport, motivation, and self-management with especially high ratings for positive feedback and engagement, review of stressors and goal setting. The Motivational Care Planning-Adherence Scale has the potential to provide a measure of quality of delivery of Motivation Care Planning. The pilot findings suggest that despite challenges within the remote Indigenous community setting, Indigenous therapists delivered therapy that was of high fidelity. While developed as a research tool, the scale has the potential to support fidelity of delivery of Motivation Care Planning in clinical, supervision and training settings. Larger studies are needed to establish inter-rater reliability and internal and external validity.

END-DIASTOLIC FLOW REVERSAL LIMITS THE EFFICACY OF PEDIATRIC INTRAAORTIC BALLOON PUMP COUNTERPULSATION

PubMed Central

Bartoli, Carlo R.; Rogers, Benjamin D.; Ionan, Constantine E.; Koenig, Steven C.; Pantalos, George M.

2013-01-01

OBJECTIVE Counterpulsation with an intraaortic balloon pump (IABP) has not achieved the same successes or clinical use in pediatric patients as in adults. In a pediatric animal model, IABP efficacy was investigated to determine whether IABP timing with a high-fidelity blood pressure signal may improve counterpulsation therapy versus a low-fidelity signal. METHODS In Yorkshire piglets (n=19, 13.0±0.5 kg) with coronary ligation-induced acute ischemic left ventricular failure, pediatric IABPs (5 or 7cc) were placed in the descending thoracic aorta. Inflation and deflation were timed with traditional criteria from low-fidelity (fluid-filled) and high-fidelity (micromanometer) blood pressure signals during 1:1 support. Aortic, carotid, and coronary hemodynamics were measured with pressure and flow transducers. Myocardial oxygen consumption was calculated from coronary sinus and arterial blood samples. Left ventricular myocardial blood flow and end-organ blood flow were measured with microspheres. RESULTS Despite significant suprasystolic diastolic augmentation and afterload reduction at heart rates of 105±3bmp, left ventricular myocardial blood flow, myocardial oxygen consumption, the myocardial oxygen supply/demand relationship, cardiac output, and end-organ blood flow did not change. Statistically significant end-diastolic coronary, carotid, and aortic flow reversal occurred with IABP deflation. Inflation and deflation timed with a high-fidelity versus low-fidelity signal did not attenuate systemic flow reversal or improve the myocardial oxygen supply/demand relationship. CONCLUSIONS Systemic end-diastolic flow reversal limited counterpulsation efficacy in a pediatric model of acute left ventricular failure. Adjustment of IABP inflation and deflation timing with traditional criteria and a high-fidelity blood pressure waveform did not improve IABP efficacy or attenuate flow reversal. End-diastolic flow reversal may limit the efficacy of IABP counterpulsation therapy in pediatric patients with traditional timing criteria. Investigation of alternative deflation timing strategies is warranted. PMID:24139614

End-diastolic flow reversal limits the efficacy of pediatric intra-aortic balloon pump counterpulsation.

PubMed

Bartoli, Carlo R; Rogers, Benjamin D; Ionan, Constantine E; Pantalos, George M

2014-05-01

Counterpulsation with an intra-aortic balloon pump (IABP) has not achieved the same success or clinical use in pediatric patients as in adults. In a pediatric animal model, IABP efficacy was investigated to determine whether IABP timing with a high-fidelity blood pressure signal may improve counterpulsation therapy versus a low-fidelity signal. In Yorkshire piglets (n = 19; weight, 13.0 ± 0.5 kg) with coronary ligation-induced acute ischemic left ventricular failure, pediatric IABPs (5 or 7 mL) were placed in the descending thoracic aorta. Inflation and deflation were timed with traditional criteria from low-fidelity (fluid-filled) and high-fidelity (micromanometer) blood pressure signals during 1:1 support. Aortic, carotid, and coronary hemodynamics were measured with pressure and flow transducers. Myocardial oxygen consumption was calculated from coronary sinus and arterial blood samples. Left ventricular myocardial blood flow and end-organ blood flow were measured with microspheres. Despite significant suprasystolic diastolic augmentation and afterload reduction at heart rates of 105 ± 3 beats per minute, left ventricular myocardial blood flow, myocardial oxygen consumption, the myocardial oxygen supply/demand relationship, cardiac output, and end-organ blood flow did not change. Statistically significant end-diastolic coronary, carotid, and aortic flow reversal occurred with IABP deflation. Inflation and deflation timed with a high-fidelity versus low-fidelity signal did not attenuate systemic flow reversal or improve the myocardial oxygen supply/demand relationship. Systemic end-diastolic flow reversal limited counterpulsation efficacy in a pediatric model of acute left ventricular failure. Adjustment of IABP inflation and deflation timing with traditional criteria and a high-fidelity blood pressure waveform did not improve IABP efficacy or attenuate flow reversal. End-diastolic flow reversal may limit the efficacy of IABP counterpulsation therapy in pediatric patients with traditional timing criteria. Investigation of alternative deflation timing strategies is warranted. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Multifunctional Collaborative Modeling and Analysis Methods in Engineering Science

NASA Technical Reports Server (NTRS)

Ransom, Jonathan B.; Broduer, Steve (Technical Monitor)

2001-01-01

Engineers are challenged to produce better designs in less time and for less cost. Hence, to investigate novel and revolutionary design concepts, accurate, high-fidelity results must be assimilated rapidly into the design, analysis, and simulation process. This assimilation should consider diverse mathematical modeling and multi-discipline interactions necessitated by concepts exploiting advanced materials and structures. Integrated high-fidelity methods with diverse engineering applications provide the enabling technologies to assimilate these high-fidelity, multi-disciplinary results rapidly at an early stage in the design. These integrated methods must be multifunctional, collaborative, and applicable to the general field of engineering science and mechanics. Multifunctional methodologies and analysis procedures are formulated for interfacing diverse subdomain idealizations including multi-fidelity modeling methods and multi-discipline analysis methods. These methods, based on the method of weighted residuals, ensure accurate compatibility of primary and secondary variables across the subdomain interfaces. Methods are developed using diverse mathematical modeling (i.e., finite difference and finite element methods) and multi-fidelity modeling among the subdomains. Several benchmark scalar-field and vector-field problems in engineering science are presented with extensions to multidisciplinary problems. Results for all problems presented are in overall good agreement with the exact analytical solution or the reference numerical solution. Based on the results, the integrated modeling approach using the finite element method for multi-fidelity discretization among the subdomains is identified as most robust. The multiple-method approach is advantageous when interfacing diverse disciplines in which each of the method's strengths are utilized. The multifunctional methodology presented provides an effective mechanism by which domains with diverse idealizations are interfaced. This capability rapidly provides the high-fidelity results needed in the early design phase. Moreover, the capability is applicable to the general field of engineering science and mechanics. Hence, it provides a collaborative capability that accounts for interactions among engineering analysis methods.

Using high-fidelity computational fluid dynamics to help design a wind turbine wake measurement experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Churchfield, M.; Wang, Q.; Scholbrock, A.

Here, we describe the process of using large-eddy simulations of wind turbine wake flow to help design a wake measurement campaign. The main goal of the experiment is to measure wakes and wake deflection that result from intentional yaw misalignment under a variety of atmospheric conditions at the Scaled Wind Farm Technology facility operated by Sandia National Laboratories in Lubbock, Texas. Prior simulation studies have shown that wake deflection may be used for wind-plant control that maximizes plant power output. In this study, simulations are performed to characterize wake deflection and general behavior before the experiment is performed to ensuremore » better upfront planning. Beyond characterizing the expected wake behavior, we also use the large-eddy simulation to test a virtual version of the lidar we plan to use to measure the wake and better understand our lidar scan strategy options. This work is an excellent example of a 'simulation-in-the-loop' measurement campaign.« less

Using High-Fidelity Computational Fluid Dynamics to Help Design a Wind Turbine Wake Measurement Experiment

NASA Astrophysics Data System (ADS)

Churchfield, M.; Wang, Q.; Scholbrock, A.; Herges, T.; Mikkelsen, T.; Sjöholm, M.

2016-09-01

We describe the process of using large-eddy simulations of wind turbine wake flow to help design a wake measurement campaign. The main goal of the experiment is to measure wakes and wake deflection that result from intentional yaw misalignment under a variety of atmospheric conditions at the Scaled Wind Farm Technology facility operated by Sandia National Laboratories in Lubbock, Texas. Prior simulation studies have shown that wake deflection may be used for wind-plant control that maximizes plant power output. In this study, simulations are performed to characterize wake deflection and general behavior before the experiment is performed to ensure better upfront planning. Beyond characterizing the expected wake behavior, we also use the large-eddy simulation to test a virtual version of the lidar we plan to use to measure the wake and better understand our lidar scan strategy options. This work is an excellent example of a “simulation-in-the-loop” measurement campaign.

[Construction and Application of Innovative Education Technology Strategies in Nursing].

PubMed

Chao, Li-Fen; Huang, Hsiang-Ping; Ni, Lee-Fen; Tsai, Chia-Lan; Huang, Tsuey-Yuan

2017-12-01

The evolution of information and communication technologies has deeply impacted education reform, promoted the development of digital-learning models, and stimulated the development of diverse nursing education strategies in order to better fulfill needs and expand in new directions. The present paper introduces the intelligent-learning resources that are available for basic medical science education, problem-based learning, nursing scenario-based learning, objective structured clinical examinations, and other similar activities in the Department of Nursing at Chang Gung University of Science and Technology. The program is offered in two parts: specialized classroom facilities and cloud computing / mobile-learning. The latter includes high-fidelity simulation classrooms, online e-books, and virtual interactive simulation and augmented reality mobile-learning materials, which are provided through multimedia technology development, learning management systems, web-certificated examinations, and automated teaching and learning feedback mechanisms. It is expected that the teaching experiences that are shared in this article may be used as a reference for applying professional wisdom teaching models into nursing education.

Mixed-Dimensionality VLSI-Type Configurable Tools for Virtual Prototyping of Biomicrofluidic Devices and Integrated Systems

NASA Astrophysics Data System (ADS)

Makhijani, Vinod B.; Przekwas, Andrzej J.

2002-10-01

This report presents results of a DARPA/MTO Composite CAD Project aimed to develop a comprehensive microsystem CAD environment, CFD-ACE+ Multiphysics, for bio and microfluidic devices and complete microsystems. The project began in July 1998, and was a three-year team effort between CFD Research Corporation, California Institute of Technology (CalTech), University of California, Berkeley (UCB), and Tanner Research, with Mr. Don Verlee from Abbott Labs participating as a consultant on the project. The overall objective of this project was to develop, validate and demonstrate several applications of a user-configurable VLSI-type mixed-dimensionality software tool for design of biomicrofluidics devices and integrated systems. The developed tool would provide high fidelity 3-D multiphysics modeling capability, l-D fluidic circuits modeling, and SPICE interface for system level simulations, and mixed-dimensionality design. It would combine tools for layouts and process fabrication, geometric modeling, and automated grid generation, and interfaces to EDA tools (e.g. Cadence) and MCAD tools (e.g. ProE).

Innovations in surgery simulation: a review of past, current and future techniques

PubMed Central

Burtt, Karen; Solorzano, Carlos A.; Carey, Joseph N.

2016-01-01

As a result of recent work-hours limitations and concerns for patient safety, innovations in extraclinical surgical simulation have become a desired part of residency education. Current simulation models, including cadaveric, animal, bench-top, virtual reality (VR) and robotic simulators are increasingly used in surgical training programs. Advances in telesurgery, three-dimensional (3D) printing, and the incorporation of patient-specific anatomy are paving the way for simulators to become integral components of medical training in the future. Evidence from the literature highlights the benefits of including simulations in surgical training; skills acquired through simulations translate into improvements in operating room performance. Moreover, simulations are rapidly incorporating new medical technologies and offer increasingly high-fidelity recreations of procedures. As a result, both novice and expert surgeons are able to benefit from their use. As dedicated, structured curricula are developed that incorporate simulations into daily resident training, simulated surgeries will strengthen the surgeon’s skill set, decrease hospital costs, and improve patient outcomes. PMID:28090509

Innovations in surgery simulation: a review of past, current and future techniques.

PubMed

Badash, Ido; Burtt, Karen; Solorzano, Carlos A; Carey, Joseph N

2016-12-01

As a result of recent work-hours limitations and concerns for patient safety, innovations in extraclinical surgical simulation have become a desired part of residency education. Current simulation models, including cadaveric, animal, bench-top, virtual reality (VR) and robotic simulators are increasingly used in surgical training programs. Advances in telesurgery, three-dimensional (3D) printing, and the incorporation of patient-specific anatomy are paving the way for simulators to become integral components of medical training in the future. Evidence from the literature highlights the benefits of including simulations in surgical training; skills acquired through simulations translate into improvements in operating room performance. Moreover, simulations are rapidly incorporating new medical technologies and offer increasingly high-fidelity recreations of procedures. As a result, both novice and expert surgeons are able to benefit from their use. As dedicated, structured curricula are developed that incorporate simulations into daily resident training, simulated surgeries will strengthen the surgeon's skill set, decrease hospital costs, and improve patient outcomes.

Using high-fidelity computational fluid dynamics to help design a wind turbine wake measurement experiment

DOE PAGES

Churchfield, M.; Wang, Q.; Scholbrock, A.; ...

2016-10-03

Here, we describe the process of using large-eddy simulations of wind turbine wake flow to help design a wake measurement campaign. The main goal of the experiment is to measure wakes and wake deflection that result from intentional yaw misalignment under a variety of atmospheric conditions at the Scaled Wind Farm Technology facility operated by Sandia National Laboratories in Lubbock, Texas. Prior simulation studies have shown that wake deflection may be used for wind-plant control that maximizes plant power output. In this study, simulations are performed to characterize wake deflection and general behavior before the experiment is performed to ensuremore » better upfront planning. Beyond characterizing the expected wake behavior, we also use the large-eddy simulation to test a virtual version of the lidar we plan to use to measure the wake and better understand our lidar scan strategy options. This work is an excellent example of a 'simulation-in-the-loop' measurement campaign.« less

High-Fidelity Rapid Initialization and Read-Out of an Electron Spin via the Single Donor D(-) Charge State.

PubMed

Watson, T F; Weber, B; House, M G; Büch, H; Simmons, M Y

2015-10-16

We demonstrate high-fidelity electron spin read-out of a precision placed single donor in silicon via spin selective tunneling to either the D(+) or D(-) charge state of the donor. By performing read-out at the stable two electron D(0)↔D(-) charge transition we can increase the tunnel rates to a nearby single electron transistor charge sensor by nearly 2 orders of magnitude, allowing faster qubit read-out (1 ms) with minimum loss in read-out fidelity (98.4%) compared to read-out at the D(+)↔D(0) transition (99.6%). Furthermore, we show that read-out via the D(-) charge state can be used to rapidly initialize the electron spin qubit in its ground state with a fidelity of F(I)=99.8%.

Measures of fidelity of delivery of, and engagement with, complex, face-to-face health behaviour change interventions: A systematic review of measure quality.

PubMed

Walton, Holly; Spector, Aimee; Tombor, Ildiko; Michie, Susan

2017-11-01

Understanding the effectiveness of complex, face-to-face health behaviour change interventions requires high-quality measures to assess fidelity of delivery and engagement. This systematic review aimed to (1) identify the types of measures used to monitor fidelity of delivery of, and engagement with, complex, face-to-face health behaviour change interventions and (2) describe the reporting of psychometric and implementation qualities. Electronic databases were searched, systematic reviews and reference lists were hand-searched, and 21 experts were contacted to identify articles. Studies that quantitatively measured fidelity of delivery of, and/or engagement with, a complex, face-to-face health behaviour change intervention for adults were included. Data on interventions, measures, and psychometric and implementation qualities were extracted and synthesized using narrative analysis. Sixty-six studies were included: 24 measured both fidelity of delivery and engagement, 20 measured fidelity of delivery, and 22 measured engagement. Measures of fidelity of delivery included observation (n = 17; 38.6%), self-report (n = 15; 34%), quantitatively rated qualitative interviews (n = 1; 2.3%), or multiple measures (n = 11; 25%). Measures of engagement included self-report (n = 18; 39.1%), intervention records (n = 11; 24%), or multiple measures (n = 17; 37%). Fifty-one studies (77%) reported at least one psychometric or implementation quality; 49 studies (74.2%) reported at least one psychometric quality, and 17 studies (25.8%) reported at least one implementation quality. Fewer than half of the reviewed studies measured both fidelity of delivery of, and engagement with complex, face-to-face health behaviour change interventions. More studies reported psychometric qualities than implementation qualities. Interpretation of intervention outcomes from fidelity of delivery and engagement measurements may be limited due to a lack of reporting of psychometric and implementation qualities. Statement of contribution What is already known on this subject? Evidence of fidelity and engagement is needed to understand effectiveness of complex interventions Evidence of fidelity and engagement are rarely reported High-quality measures are needed to measure fidelity and engagement What does this study add? Evidence that indicators of quality of measures are reported in some studies Evidence that psychometric qualities are reported more frequently than implementation qualities A recommendation for intervention evaluations to report indicators of quality of fidelity and engagement measures. © 2017 The Authors. British Journal of Health Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

Spin qubit transport in a double quantum dot

NASA Astrophysics Data System (ADS)

Zhao, Xinyu; Hu, Xuedong

Long distance spin communication is a crucial ingredient to scalable quantum computer architectures based on electron spin qubits. One way to transfer spin information over a long distance on chip is via electron transport. Here we study the transport of an electron spin qubit in a double quantum dot by tuning the interdot detuning voltage. We identify a parameter regime where spin relaxation hot-spots can be avoided and high-fidelity spin transport is possible. Within this parameter space, the spin transfer fidelity is determined by the operation speed and the applied magnetic field. In particular, near zero detuning, a proper choice of operation speed is essential to high fidelity. In addition, we also investigate the modification of the effective g-factor by the interdot detuning, which could lead to a phase error between spin up and down states. The results presented in this work could be a useful guidance for experimentally achieving high-fidelity spin qubit transport. We thank financial support by US ARO via Grant W911NF1210609.

The Relationship Between Fidelity and Learning in Aviation Training and Assessment

NASA Technical Reports Server (NTRS)

Noble, Cliff

2002-01-01

Flight simulators can be designed to train pilots or assess their flight performance. Low-Fidelity simulators maximize the initial learning rate of novice pilots and minimize initial costs; whereas, expensive, high-fidelity simulators predict the realworld in-flight performance of expert pilots (Fink & Shriver, 1978 Hays & Singer 1989; Kinkade & Wheaton. 1972). Although intuitively appealing and intellectually convenient to generalize concepts of learning and assessment, what holds true for the role of fidelity in assessment may not always hold true for learning, and vice versa. To bring clarity to this issue, the author distinguishes the role of fidelity in learning from its role in assessment as a function of skill level by applying the hypothesis of Alessi (1988) and reviewing the Laughery, Ditzian, and Houtman (1982) study on simulator validity. Alessi hypothesized that there is it point beyond which one additional unit of flight-simulator fidelity results in a diminished rate of learning. The author of this current paper also suggests the existence of an optimal point beyond which one additional unit of flight-simulator fidelity results in a diminished rate of practical assessment of nonexpert pilot performance.

High fidelity quantum gates with vibrational qubits.

PubMed

Berrios, Eduardo; Gruebele, Martin; Shyshlov, Dmytro; Wang, Lei; Babikov, Dmitri

2012-11-26

Physical implementation of quantum gates acting on qubits does not achieve a perfect fidelity of 1. The actual output qubit may not match the targeted output of the desired gate. According to theoretical estimates, intrinsic gate fidelities >99.99% are necessary so that error correction codes can be used to achieve perfect fidelity. Here we test what fidelity can be accomplished for a CNOT gate executed by a shaped ultrafast laser pulse interacting with vibrational states of the molecule SCCl(2). This molecule has been used as a test system for low-fidelity calculations before. To make our test more stringent, we include vibrational levels that do not encode the desired qubits but are close enough in energy to interfere with population transfer by the laser pulse. We use two complementary approaches: optimal control theory determines what the best possible pulse can do; a more constrained physical model calculates what an experiment likely can do. Optimal control theory finds pulses with fidelity >0.9999, in excess of the quantum error correction threshold with 8 × 10(4) iterations. On the other hand, the physical model achieves only 0.9992 after 8 × 10(4) iterations. Both calculations converge as an inverse power law toward unit fidelity after >10(2) iterations/generations. In principle, the fidelities necessary for quantum error correction are reachable with qubits encoded by molecular vibrations. In practice, it will be challenging with current laboratory instrumentation because of slow convergence past fidelities of 0.99.

Enhancing the control of force in putting by video game training.

PubMed

Fery, Y A; Ponserre, S

2001-10-10

Even if golf video games provide no proprioceptive afferences on actual putting movement, they may give sufficient substitutive visual cues to enhance force control in this skill. It was hypothesized that this usefulness requires, however, two conditions: the video game must provide reliable demonstrations of actual putts, and the user must want to use the game to make progress in actual putting. Accordingly, a video game was selected on the basis of its fidelity to the real-world game. It allowed two different methods of adjusting the virtual player's putting force in order to hole a putt: an analogue method that consisted of focusing on the virtual player's movement and a symbolic method that consisted of focusing on the movement of a gauge on a scale representing the virtual player's putting force. The participants had to use one of these methods with either the intention of making progress in actual putting or in a second condition to simply enjoy the game. Results showed a positive transfer of video playing to actual putting skill for the learning group and also, to a lesser degree, for the enjoyment group; but only when they used the symbolic method. Results are discussed in the context of how vision may convey force cues in sports video games.

Simulation-Based Training for Colonoscopy

PubMed Central

Preisler, Louise; Svendsen, Morten Bo Søndergaard; Nerup, Nikolaj; Svendsen, Lars Bo; Konge, Lars

2015-01-01

Abstract The aim of this study was to create simulation-based tests with credible pass/fail standards for 2 different fidelities of colonoscopy models. Only competent practitioners should perform colonoscopy. Reliable and valid simulation-based tests could be used to establish basic competency in colonoscopy before practicing on patients. Twenty-five physicians (10 consultants with endoscopic experience and 15 fellows with very little endoscopic experience) were tested on 2 different simulator models: a virtual-reality simulator and a physical model. Tests were repeated twice on each simulator model. Metrics with discriminatory ability were identified for both modalities and reliability was determined. The contrasting-groups method was used to create pass/fail standards and the consequences of these were explored. The consultants significantly performed faster and scored higher than the fellows on both the models (P < 0.001). Reliability analysis showed Cronbach α = 0.80 and 0.87 for the virtual-reality and the physical model, respectively. The established pass/fail standards failed one of the consultants (virtual-reality simulator) and allowed one fellow to pass (physical model). The 2 tested simulations-based modalities provided reliable and valid assessments of competence in colonoscopy and credible pass/fail standards were established for both the tests. We propose to use these standards in simulation-based training programs before proceeding to supervised training on patients. PMID:25634177

High Fidelity: Investing in Evaluation Training. Ask the Team

ERIC Educational Resources Information Center

Fetters, Jenni

2013-01-01

High-quality training is a crucial investment in establishing and maintaining implementation fidelity as well as building educators' trust in the new process. Training approaches for educator evaluation vary both in format (i.e., how it's delivered) and content (i.e., what is provided). Train-the-trainer sessions, online professional learning…

Designing High Fidelity Simulation to Maximize Student Registered Nursing Decision-Making Ability

ERIC Educational Resources Information Center

Deckers, Cathleen

2011-01-01

The current healthcare environment is a complex system of patients, procedures, and equipment that strives to deliver safe and effective medical care. High fidelity simulation provides healthcare educators with a tool to create safety conscious practitioners utilizing an environment that replicates practice without risk to patients. Using HFS…

76 FR 60047 - Agency Information Collection Activities; Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-28

... Response: Periodic. Total Annual Labor Cost: $18,300 per year ($12,900 for testing + $5,400 for disclosures... and Estimated Burden: (a) Testing--High fidelity manufacturers--300 new products/year x 1 hour each = 300 hours; and (b) Disclosures--High fidelity manufacturers--[(300 new products/ year x 1...

Exploring Interprofessional Education through a High-Fidelity Human Patient Simulation Scenario: A Mixed Methods Study

ERIC Educational Resources Information Center

Rossler, Kelly Lynn

2013-01-01

High-fidelity human patient simulation has emerged as a valuable medium to reinforce educational content within programs of nursing. As simulation learning experiences have been identified as augmenting both didactic lecture content and clinical learning, these experiences have expanded to incorporate interprofessional education. Review of…

The Impact of Human Patient Simulation on the Attainment of Learning Outcomes

ERIC Educational Resources Information Center

Re, Antonio

2011-01-01

Human patient simulation, and more specifically, high fidelity patient simulation is a growing teaching technique that enables students in medical and health related professions to learn through interacting with a simulator. This study examined the uses of high fidelity simulation with 106 students enrolled in nursing and respiratory therapist…

The Development of the Simulation Thinking Rubric

ERIC Educational Resources Information Center

Doolen, Jessica

2012-01-01

High fidelity simulation has become a widespread and costly learning strategy in nursing education because it can fill the gap left by a shortage of clinical sites. In addition, high fidelity simulation is an active learning strategy that is thought to increase higher order thinking such as clinical reasoning and judgment skills in nursing…

Framework for Multidisciplinary Analysis, Design, and Optimization with High-Fidelity Analysis Tools

NASA Technical Reports Server (NTRS)

Orr, Stanley A.; Narducci, Robert P.

2009-01-01

A plan is presented for the development of a high fidelity multidisciplinary optimization process for rotorcraft. The plan formulates individual disciplinary design problems, identifies practical high-fidelity tools and processes that can be incorporated in an automated optimization environment, and establishes statements of the multidisciplinary design problem including objectives, constraints, design variables, and cross-disciplinary dependencies. Five key disciplinary areas are selected in the development plan. These are rotor aerodynamics, rotor structures and dynamics, fuselage aerodynamics, fuselage structures, and propulsion / drive system. Flying qualities and noise are included as ancillary areas. Consistency across engineering disciplines is maintained with a central geometry engine that supports all multidisciplinary analysis. The multidisciplinary optimization process targets the preliminary design cycle where gross elements of the helicopter have been defined. These might include number of rotors and rotor configuration (tandem, coaxial, etc.). It is at this stage that sufficient configuration information is defined to perform high-fidelity analysis. At the same time there is enough design freedom to influence a design. The rotorcraft multidisciplinary optimization tool is built and substantiated throughout its development cycle in a staged approach by incorporating disciplines sequentially.

High-Fidelity Buckling Analysis of Composite Cylinders Using the STAGS Finite Element Code

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.

2014-01-01

Results from previous shell buckling studies are presented that illustrate some of the unique and powerful capabilities in the STAGS finite element analysis code that have made it an indispensable tool in structures research at NASA over the past few decades. In particular, prototypical results from the development and validation of high-fidelity buckling simulations are presented for several unstiffened thin-walled compression-loaded graphite-epoxy cylindrical shells along with a discussion on the specific methods and user-defined subroutines in STAGS that are used to carry out the high-fidelity simulations. These simulations accurately account for the effects of geometric shell-wall imperfections, shell-wall thickness variations, local shell-wall ply-gaps associated with the fabrication process, shell-end geometric imperfections, nonuniform applied end loads, and elastic boundary conditions. The analysis procedure uses a combination of nonlinear quasi-static and transient dynamic solution algorithms to predict the prebuckling and unstable collapse response characteristics of the cylinders. Finally, the use of high-fidelity models in the development of analysis-based shell-buckling knockdown (design) factors is demonstrated.

Development of a patient-specific surgical simulator for pediatric laparoscopic procedures.

PubMed

Saber, Nikoo R; Menon, Vinay; St-Pierre, Jean C; Looi, Thomas; Drake, James M; Cyril, Xavier

2014-01-01

The purpose of this study is to develop and evaluate a pediatric patient-specific surgical simulator for the planning, practice, and validation of laparoscopic surgical procedures prior to intervention, initially focusing on the choledochal cyst resection and reconstruction scenario. The simulator is comprised of software elements including a deformable body physics engine, virtual surgical tools, and abdominal organs. Hardware components such as haptics-enabled hand controllers and a representative endoscopic tool have also been integrated. The prototype is able to perform a number of surgical tasks and further development work is under way to simulate the complete procedure with acceptable fidelity and accuracy.

Investigation of Control Inceptor Dynamics and Effect on Human Subject Performance

NASA Technical Reports Server (NTRS)

Stanco, Anthony A.; Cardullo, Frank M.; Houck, Jacob A.; Grube, Richard C.; Kelly, Lon C.

2013-01-01

The control inceptor used in a vehicle simulation is an important part of adequately representing the dynamics of the vehicle. The inceptor characteristics are typically based on a second order spring mass damper system with damping, force gradient, breakout force, and natural frequency parameters. Changing these parameters can have a great effect on pilot control of the vehicle. A quasi transfer of training experiment was performed employing a high fidelity and a low fidelity control inceptor. A disturbance compensatory task was employed which involved a simple horizon line disturbed in roll by a sum of sinusoids presented in an out-the-window display. Vehicle dynamics were modeled as 1/s and 1/s2. The task was to maintain level flight. Twenty subjects were divided between the high and the low fidelity training groups. Each group was trained to a performance asymptote, and then transferred to the high fidelity simulation. RMS tracking error, a PSD analysis, and a workload analysis were performed to quantify the transfer of training effect. Quantitative results of the experiments show that there is no significant difference between the high and low fidelity training groups for 1/s plant dynamics. For 1/s2 plant dynamics there is a greater difference in tracking performance and PSD; and the subjects are less correlated with the input disturbance function

Zero-Fidelity Simulation: Engaging Team Coordination without Physical, Functional, or Psychological Re-Creation

NASA Technical Reports Server (NTRS)

Toups, Zachary O.; Hamilton, William A.; Kerne, Andruid

2012-01-01

Team coordination is essential across domains, enabling efficiency and safety. As technology improves, our temptation is to simulate with ever-higher fidelity, by making simulators re-create reality through their physical interfaces, functionality, and by making participants believe they are undertaking the simulated task. However, high-fidelity simulations often miss salient human-human work practices. We introduce the concept of zero-fidelity simulation (ZFS), a move away from literal high-fidelity mimesis of the concrete environment. ZFS alternatively models cooperation and communication as the basis of simulation. The ZFS Team Coordination Game (TeC) is developed from observation of fire emergency response work practice. We identify ways in which team members are mutually dependent on one another for information, and use these as the basis for the ZFS game design. The design creates a need for cooperation by restricting individual activity and requiring communication. The present research analyzes the design of interdependence in the validated ZFS TeC game. We successfully simulate interdependence between roles in emergency response without simulating the concrete environment.

Blending Qualitative and Computational Linguistics Methods for Fidelity Assessment: Experience with the Familias Unidas Preventive Intervention.

PubMed

Gallo, Carlos; Pantin, Hilda; Villamar, Juan; Prado, Guillermo; Tapia, Maria; Ogihara, Mitsunori; Cruden, Gracelyn; Brown, C Hendricks

2015-09-01

Careful fidelity monitoring and feedback are critical to implementing effective interventions. A wide range of procedures exist to assess fidelity; most are derived from observational assessments (Schoenwald and Garland, Psycholog Assess 25:146-156, 2013). However, these fidelity measures are resource intensive for research teams in efficacy/effectiveness trials, and are often unattainable or unmanageable for the host organization to rate when the program is implemented on a large scale. We present a first step towards automated processing of linguistic patterns in fidelity monitoring of a behavioral intervention using an innovative mixed methods approach to fidelity assessment that uses rule-based, computational linguistics to overcome major resource burdens. Data come from an effectiveness trial of the Familias Unidas intervention, an evidence-based, family-centered preventive intervention found to be efficacious in reducing conduct problems, substance use and HIV sexual risk behaviors among Hispanic youth. This computational approach focuses on "joining," which measures the quality of the working alliance of the facilitator with the family. Quantitative assessments of reliability are provided. Kappa scores between a human rater and a machine rater for the new method for measuring joining reached 0.83. Early findings suggest that this approach can reduce the high cost of fidelity measurement and the time delay between fidelity assessment and feedback to facilitators; it also has the potential for improving the quality of intervention fidelity ratings.

Blending Qualitative and Computational Linguistics Methods for Fidelity Assessment: Experience with the Familias Unidas Preventive Intervention

PubMed Central

Gallo, Carlos; Pantin, Hilda; Villamar, Juan; Prado, Guillermo; Tapia, Maria; Ogihara, Mitsunori; Cruden, Gracelyn; Brown, C Hendricks

2014-01-01

Careful fidelity monitoring and feedback are critical to implementing effective interventions. A wide range of procedures exist to assess fidelity; most are derived from observational assessments (Schoenwald et al, 2013). However, these fidelity measures are resource intensive for research teams in efficacy/effectiveness trials, and are often unattainable or unmanageable for the host organization to rate when the program is implemented on a large scale. We present a first step towards automated processing of linguistic patterns in fidelity monitoring of a behavioral intervention using an innovative mixed methods approach to fidelity assessment that uses rule-based, computational linguistics to overcome major resource burdens. Data come from an effectiveness trial of the Familias Unidas intervention, an evidence-based, family-centered preventive intervention found to be efficacious in reducing conduct problems, substance use and HIV sexual risk behaviors among Hispanic youth. This computational approach focuses on “joining,” which measures the quality of the working alliance of the facilitator with the family. Quantitative assessments of reliability are provided. Kappa scores between a human rater and a machine rater for the new method for measuring joining reached .83. Early findings suggest that this approach can reduce the high cost of fidelity measurement and the time delay between fidelity assessment and feedback to facilitators; it also has the potential for improving the quality of intervention fidelity ratings. PMID:24500022

Development and Implementation of CFD-Informed Models for the Advanced Subchannel Code CTF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blyth, Taylor S.; Avramova, Maria

The research described in this PhD thesis contributes to the development of efficient methods for utilization of high-fidelity models and codes to inform low-fidelity models and codes in the area of nuclear reactor core thermal-hydraulics. The objective is to increase the accuracy of predictions of quantities of interests using high-fidelity CFD models while preserving the efficiency of low-fidelity subchannel core calculations. An original methodology named Physics- based Approach for High-to-Low Model Information has been further developed and tested. The overall physical phenomena and corresponding localized effects, which are introduced by the presence of spacer grids in light water reactor (LWR)more » cores, are dissected in corresponding four building basic processes, and corresponding models are informed using high-fidelity CFD codes. These models are a spacer grid-directed cross-flow model, a grid-enhanced turbulent mixing model, a heat transfer enhancement model, and a spacer grid pressure loss model. The localized CFD-models are developed and tested using the CFD code STAR-CCM+, and the corresponding global model development and testing in sub-channel formulation is performed in the thermal- hydraulic subchannel code CTF. The improved CTF simulations utilize data-files derived from CFD STAR-CCM+ simulation results covering the spacer grid design desired for inclusion in the CTF calculation. The current implementation of these models is examined and possibilities for improvement and further development are suggested. The validation experimental database is extended by including the OECD/NRC PSBT benchmark data. The outcome is an enhanced accuracy of CTF predictions while preserving the computational efficiency of a low-fidelity subchannel code.« less

Development and Implementation of CFD-Informed Models for the Advanced Subchannel Code CTF

NASA Astrophysics Data System (ADS)

Blyth, Taylor S.

The research described in this PhD thesis contributes to the development of efficient methods for utilization of high-fidelity models and codes to inform low-fidelity models and codes in the area of nuclear reactor core thermal-hydraulics. The objective is to increase the accuracy of predictions of quantities of interests using high-fidelity CFD models while preserving the efficiency of low-fidelity subchannel core calculations. An original methodology named Physics-based Approach for High-to-Low Model Information has been further developed and tested. The overall physical phenomena and corresponding localized effects, which are introduced by the presence of spacer grids in light water reactor (LWR) cores, are dissected in corresponding four building basic processes, and corresponding models are informed using high-fidelity CFD codes. These models are a spacer grid-directed cross-flow model, a grid-enhanced turbulent mixing model, a heat transfer enhancement model, and a spacer grid pressure loss model. The localized CFD-models are developed and tested using the CFD code STAR-CCM+, and the corresponding global model development and testing in sub-channel formulation is performed in the thermal-hydraulic subchannel code CTF. The improved CTF simulations utilize data-files derived from CFD STAR-CCM+ simulation results covering the spacer grid design desired for inclusion in the CTF calculation. The current implementation of these models is examined and possibilities for improvement and further development are suggested. The validation experimental database is extended by including the OECD/NRC PSBT benchmark data. The outcome is an enhanced accuracy of CTF predictions while preserving the computational efficiency of a low-fidelity subchannel code.

A hardware and software architecture to deal with multimodal and collaborative interactions in multiuser virtual reality environments

NASA Astrophysics Data System (ADS)

Martin, P.; Tseu, A.; Férey, N.; Touraine, D.; Bourdot, P.

2014-02-01

Most advanced immersive devices provide collaborative environment within several users have their distinct head-tracked stereoscopic point of view. Combining with common used interactive features such as voice and gesture recognition, 3D mouse, haptic feedback, and spatialized audio rendering, these environments should faithfully reproduce a real context. However, even if many studies have been carried out on multimodal systems, we are far to definitively solve the issue of multimodal fusion, which consists in merging multimodal events coming from users and devices, into interpretable commands performed by the application. Multimodality and collaboration was often studied separately, despite of the fact that these two aspects share interesting similarities. We discuss how we address this problem, thought the design and implementation of a supervisor that is able to deal with both multimodal fusion and collaborative aspects. The aim of this supervisor is to ensure the merge of user's input from virtual reality devices in order to control immersive multi-user applications. We deal with this problem according to a practical point of view, because the main requirements of this supervisor was defined according to a industrial task proposed by our automotive partner, that as to be performed with multimodal and collaborative interactions in a co-located multi-user environment. In this task, two co-located workers of a virtual assembly chain has to cooperate to insert a seat into the bodywork of a car, using haptic devices to feel collision and to manipulate objects, combining speech recognition and two hands gesture recognition as multimodal instructions. Besides the architectural aspect of this supervisor, we described how we ensure the modularity of our solution that could apply on different virtual reality platforms, interactive contexts and virtual contents. A virtual context observer included in this supervisor in was especially designed to be independent to the content of the virtual scene of targeted application, and is use to report high-level interactive and collaborative events. This context observer allows the supervisor to merge these interactive and collaborative events, but is also used to deal with new issues coming from our observation of two co-located users in an immersive device performing this assembly task. We highlight the fact that when speech recognition features are provided to the two users, it is required to automatically detect according to the interactive context, whether the vocal instructions must be translated into commands that have to be performed by the machine, or whether they take a part of the natural communication necessary for collaboration. Information coming from this context observer that indicates a user is looking at its collaborator, is important to detect if the user is talking to its partner. Moreover, as the users are physically co-localised and head-tracking is used to provide high fidelity stereoscopic rendering, and natural walking navigation in the virtual scene, we have to deals with collision and screen occlusion between the co-located users in the physical work space. Working area and focus of each user, computed and reported by the context observer is necessary to prevent or avoid these situations.

Simulation Learning PC Screen-Based vs. High Fidelity

DTIC Science & Technology

2011-08-01

D., Burgess, L., Berg, B . and Connolly, K . (2009). Teaching mass casualty triage skills using iterative multimanikin simulations. Prehospital...SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON USAMRMC a. REPORT U b . ABSTRACT U...learning PC screen-based vs. high fidelity – progress chart Attachment B . Approved Protocol - Simulation Learning: PC-Screen Based (PCSB) versus High

Effect of diatomic molecular properties on binary laser pulse optimizations of quantum gate operations.

PubMed

Zaari, Ryan R; Brown, Alex

2011-07-28

The importance of the ro-vibrational state energies on the ability to produce high fidelity binary shaped laser pulses for quantum logic gates is investigated. The single frequency 2-qubit ACNOT(1) and double frequency 2-qubit NOT(2) quantum gates are used as test cases to examine this behaviour. A range of diatomics is sampled. The laser pulses are optimized using a genetic algorithm for binary (two amplitude and two phase parameter) variation on a discretized frequency spectrum. The resulting trends in the fidelities were attributed to the intrinsic molecular properties and not the choice of method: a discretized frequency spectrum with genetic algorithm optimization. This is verified by using other common laser pulse optimization methods (including iterative optimal control theory), which result in the same qualitative trends in fidelity. The results differ from other studies that used vibrational state energies only. Moreover, appropriate choice of diatomic (relative ro-vibrational state arrangement) is critical for producing high fidelity optimized quantum logic gates. It is also suggested that global phase alignment imposes a significant restriction on obtaining high fidelity regions within the parameter search space. Overall, this indicates a complexity in the ability to provide appropriate binary laser pulse control of diatomics for molecular quantum computing. © 2011 American Institute of Physics

Fidelity of the representation of value in decision-making

PubMed Central

Dowding, Ben A.

2017-01-01

The ability to make optimal decisions depends on evaluating the expected rewards associated with different potential actions. This process is critically dependent on the fidelity with which reward value information can be maintained in the nervous system. Here we directly probe the fidelity of value representation following a standard reinforcement learning task. The results demonstrate a previously-unrecognized bias in the representation of value: extreme reward values, both low and high, are stored significantly more accurately and precisely than intermediate rewards. The symmetry between low and high rewards pertained despite substantially higher frequency of exposure to high rewards, resulting from preferential exploitation of more rewarding options. The observed variation in fidelity of value representation retrospectively predicted performance on the reinforcement learning task, demonstrating that the bias in representation has an impact on decision-making. A second experiment in which one or other extreme-valued option was omitted from the learning sequence showed that representational fidelity is primarily determined by the relative position of an encoded value on the scale of rewards experienced during learning. Both variability and guessing decreased with the reduction in the number of options, consistent with allocation of a limited representational resource. These findings have implications for existing models of reward-based learning, which typically assume defectless representation of reward value. PMID:28248958

Demonstration of a High-Fidelity Predictive/Preview Display Technique for Telerobotic Servicing in Space

NASA Technical Reports Server (NTRS)

Kim, Won S.; Bejczy, Antal K.

1993-01-01

A highly effective predictive/preview display technique for telerobotic servicing in space under several seconds communication time delay has been demonstrated on a large laboratory scale in May 1993, involving the Jet Propulsion Laboratory as the simulated ground control station and, 2500 miles away, the Goddard Space Flight Center as the simulated satellite servicing set-up. The technique is based on a high-fidelity calibration procedure that enables a high-fidelity overlay of 3-D graphics robot arm and object models over given 2-D TV camera images of robot arm and objects. To generate robot arm motions, the operator can confidently interact in real time with the graphics models of the robot arm and objects overlaid on an actual camera view of the remote work site. The technique also enables the operator to generate high-fidelity synthetic TV camera views showing motion events that are hidden in a given TV camera view or for which no TV camera views are available. The positioning accuracy achieved by this technique for a zoomed-in camera setting was about +/-5 mm, well within the allowable +/-12 mm error margin at the insertion of a 45 cm long tool in the servicing task.

DDDAMS-based Urban Surveillance and Crowd Control via UAVs and UGVs

DTIC Science & Technology

2015-12-04

for crowd dynamics modeling by incorporating multi-resolution data, where a grid-based method is used to model crowd motion with UAVs’ low -resolution...information and more computational intensive (and time-consuming). Given that the deployment of fidelity selection results in simulation faces computational... low fidelity information FOV y (A) DR x (A) DR y (A) Not detected high fidelity information Table 1: Parameters for UAV and UGV for their detection

Survey of CIG Data Base Generation from Imagery.

DTIC Science & Technology

1980-09-01

world as measured by training transfer. There is no conclusive research as to therequired degree of realism or fidelity necessary to train. In order to...driving force behind emphasizing perceptual fidelity as opposed to realisn is the high cost of realism . Replication of all sensible attri- butes of the...and specification of visual simulation systems will con- tinue to je based on physical fidelity to the real world until those trade-offs on realism

EBT Fidelity Trajectories Across Training Cohorts Using the Interagency Collaborative Team Strategy

PubMed Central

Hecht, Debra; Aarons, Greg; Fettes, Danielle; Hurlburt, Michael; Ledesma, Karla

2015-01-01

The Interdisciplinary Collaborative Team (ICT) strategy uses front-line providers as adaptation, training and quality control agents for multi-agency EBT implementation. This study tests whether an ICT transmits fidelity to subsequent provider cohorts. SafeCare was implemented by home visitors from multiple community-based agencies contracting with child welfare. Client-reported fidelity trajectories for 5,769 visits, 957 clients and 45 providers were compared using three-level growth models. Provider cohorts trained and live-coached by the ICT attained benchmark fidelity after 12 weeks, and this was sustained. Hispanic clients reported high cultural competency, supporting a cultural adaptation crafted by the ICT. PMID:25586878

EBT Fidelity Trajectories Across Training Cohorts Using the Interagency Collaborative Team Strategy.

PubMed

Chaffin, Mark; Hecht, Debra; Aarons, Greg; Fettes, Danielle; Hurlburt, Michael; Ledesma, Karla

2016-03-01

The Interdisciplinary Collaborative Team (ICT) strategy uses front-line providers as adaptation, training and quality control agents for multi-agency EBT implementation. This study tests whether an ICT transmits fidelity to subsequent provider cohorts. SafeCare was implemented by home visitors from multiple community-based agencies contracting with child welfare. Client-reported fidelity trajectories for 5,769 visits, 957 clients and 45 providers were compared using three-level growth models. Provider cohorts trained and live-coached by the ICT attained benchmark fidelity after 12 weeks, and this was sustained. Hispanic clients reported high cultural competency, supporting a cultural adaptation crafted by the ICT.

How to Measure Motivational Interviewing Fidelity in Randomized Controlled Trials: Practical Recommendations.

PubMed

Jelsma, Judith G M; Mertens, Vera-Christina; Forsberg, Lisa; Forsberg, Lars

2015-07-01

Many randomized controlled trials in which motivational interviewing (MI) is a key intervention make no provision for the assessment of treatment fidelity. This methodological shortcoming makes it impossible to distinguish between high- and low-quality MI interventions, and, consequently, to know whether MI provision has contributed to any intervention effects. This article makes some practical recommendations for the collection, selection, coding and reporting of MI fidelity data, as measured using the Motivational Interviewing Treatment Integrity Code. We hope that researchers will consider these recommendations and include MI fidelity measures in future studies. Copyright © 2015 Elsevier Inc. All rights reserved.

Commentary: Learning from Variations in Fidelity of Implementation.

PubMed

Balu, Rekha; Doolittle, Fred

2016-12-01

The articles in this special issue discuss efforts to improve academic reading outcomes for students and ways to achieve high implementation fidelity of promising strategies. At times the authors discuss if-and how-strong fidelity is associated with strong outcomes and potentially even impacts (the difference between program and control group outcomes). We want to explore this theme in two ways: (a) learning from the variation in fidelity to think about potential points of entry and levers for improvement in implementation, and (b) broadening the evaluation focus to include "service contrast" as a factor driving impacts on student outcomes. We conclude with suggestions for future research. © 2016 Wiley Periodicals, Inc.

A method for assessing fidelity of delivery of telephone behavioral support for smoking cessation.

PubMed

Lorencatto, Fabiana; West, Robert; Bruguera, Carla; Michie, Susan

2014-06-01

Behavioral support for smoking cessation is delivered through different modalities, often guided by treatment manuals. Recently developed methods for assessing fidelity of delivery have shown that face-to-face behavioral support is often not delivered as specified in the service treatment manual. This study aimed to extend this method to evaluate fidelity of telephone-delivered behavioral support. A treatment manual and transcripts of 75 audio-recorded behavioral support sessions were obtained from the United Kingdom's national Quitline service and coded into component behavior change techniques (BCTs) using a taxonomy of 45 smoking cessation BCTs. Interrater reliability was assessed using percentage agreement. Fidelity was assessed by comparing the number of BCTs identified in the manual with those delivered in telephone sessions by 4 counselors. Fidelity was assessed according to session type, duration, counselor, and BCT. Differences between self-reported and actual BCT use were examined. Average coding reliability was high (81%). On average, 41.8% of manual-specified BCTs were delivered per session (SD = 16.2), with fidelity varying by counselor from 32% to 49%. Fidelity was highest in pre-quit sessions (46%) and for BCT "give options for additional support" (95%). Fidelity was lowest for quit-day sessions (35%) and BCT "set graded tasks" (0%). Session duration was positively correlated with fidelity (r = .585; p < .01). Significantly fewer BCTs were used than were reported as being used, t(15) = -5.52, p < .001. The content of telephone-delivered behavioral support can be reliably coded in terms of BCTs. This can be used to assess fidelity to treatment manuals and to in turn identify training needs. The observed low fidelity underlines the need to establish routine procedures for monitoring delivery of behavioral support. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Early Influences and Later Outcomes Associated With Developmental Trajectories of Eriksonian Fidelity

PubMed Central

Brittian, Aerika S.; Lerner, Richard M.

2014-01-01

Although Eriksonian theory suggests that adolescents’ sense of fidelity is a key component of healthy development, research on this psychosocial construct has been limited. The current study developed an index of youth fidelity, examined the developmental course of this construct, explored the influence of contextual factors on different fidelity trajectories, and tested if trajectories were associated with later indicators of adolescents’ positive development. Participants included 1,941 ethnically diverse youth (61% female) participants in the 4-H Study of Positive Youth Development who were recruited from schools and youth development programs across the United States. Results suggested that three types of developmental trajectories existed among youth: high and increasing, moderate and increasing, and low and decreasing. Fidelity group membership varied in relation to social relationships and psychosocial and behavioral characteristics (i.e., contribution, substance use, and delinquency). Girls were more likely than boys to be in the highest fidelity trajectories. Directions for future research and implications for enhancing the thriving of adolescents are discussed. PMID:22545838

Construction of nested maximin designs based on successive local enumeration and modified novel global harmony search algorithm

NASA Astrophysics Data System (ADS)

Yi, Jin; Li, Xinyu; Xiao, Mi; Xu, Junnan; Zhang, Lin

2017-01-01

Engineering design often involves different types of simulation, which results in expensive computational costs. Variable fidelity approximation-based design optimization approaches can realize effective simulation and efficiency optimization of the design space using approximation models with different levels of fidelity and have been widely used in different fields. As the foundations of variable fidelity approximation models, the selection of sample points of variable-fidelity approximation, called nested designs, is essential. In this article a novel nested maximin Latin hypercube design is constructed based on successive local enumeration and a modified novel global harmony search algorithm. In the proposed nested designs, successive local enumeration is employed to select sample points for a low-fidelity model, whereas the modified novel global harmony search algorithm is employed to select sample points for a high-fidelity model. A comparative study with multiple criteria and an engineering application are employed to verify the efficiency of the proposed nested designs approach.

Debriefing after High-Fidelity Simulation and Knowledge Retention: A Quasi-Experimental Study

ERIC Educational Resources Information Center

Olson, Susan L.

2013-01-01

High-fidelity simulation (HFS) use in nursing education has been a frequent research topic in recent years. Previous research included studies on the use of HFS with nursing students, focusing on their feelings of self-confidence and anxiety. However, research focused specifically on the debriefing portion of HFS was limited. This quantitative,…

Capacity Development and Multi-Tiered Systems of Support: Guiding Principles

ERIC Educational Resources Information Center

Sugai, George; Simonsen, Brandi; Freeman, Jennifer; La Salle, Tamika

2016-01-01

Implementation of multi-tiered systems of support is occurring within and across a number of countries with an increased recent focus on the development of local system capacity to maintain high levels of practice implementation fidelity. The purpose of this paper is to describe the importance of local capacity development in the high fidelity and…

High-Fidelity Patient Simulators to Expose Undergraduate Students to the Clinical Relevance of Physiology Concepts

ERIC Educational Resources Information Center

Harris, David M.; Bellew, Christine; Cheng, Zixi J.; Cendán, Juan C.; Kibble, Jonathan D.

2014-01-01

The use of high-fidelity patient simulators (HFPSs) has expanded throughout medical, nursing, and allied health professions education in the last decades. These manikins can be programmed to represent pathological states and are used to teach clinical skills as well as clinical reasoning. First, the students are typically oriented either to the…

The Effect of Learning Styles, Critical Thinking Disposition, and Critical Thinking on Clinical Judgment in Senior Baccalaureate Nursing Students during Human Patient Simulation

ERIC Educational Resources Information Center

McCormick, Kiyan

2014-01-01

Simulated learning experiences using high-fidelity human patient simulators (HPS) are increasingly being integrated into baccalaureate nursing programs. Thus, the purpose of this study was to examine relationships among learning style, critical thinking disposition, critical thinking, and clinical judgment during high-fidelity human patient…

The Effect of High-Fidelity Cardiopulmonary Resuscitation (CPR) Simulation on Athletic Training Student Knowledge, Confidence, Emotions, and Experiences

ERIC Educational Resources Information Center

Tivener, Kristin Ann; Gloe, Donna Sue

2015-01-01

Context: High-fidelity simulation is widely used in healthcare for the training and professional education of students though literature of its application to athletic training education remains sparse. Objective: This research attempts to address a wide-range of data. This includes athletic training student knowledge acquisition from…

Evaluating Outcomes of High Fidelity Simulation Curriculum in a Community College Nursing Program

ERIC Educational Resources Information Center

Denlea, Gregory Richard

2017-01-01

This study took place at a Wake Technical Community College, a multi-campus institution in Raleigh, North Carolina. An evaluation of the return on investment in high fidelity simulation used by an associate degree of nursing program was conducted with valid and reliable instruments. The study demonstrated that comparable student outcomes are…

Physics and Psychophysics of High-Fidelity Sound. Part III: The Components of a Sound-Reproducing System: Amplifiers and Loudspeakers.

ERIC Educational Resources Information Center

Rossing, Thomas D.

1980-01-01

Described are the components for a high-fidelity sound-reproducing system which focuses on various program sources, the amplifier, and loudspeakers. Discussed in detail are amplifier power and distortion, air suspension, loudspeaker baffles and enclosures, bass-reflex enclosure, drone cones, rear horn and acoustic labyrinth enclosures, horn…

Developing High-Fidelity Health Care Simulation Scenarios: A Guide for Educators and Professionals

ERIC Educational Resources Information Center

Alinier, Guillaume

2011-01-01

The development of appropriate scenarios is critical in high-fidelity simulation training. They need to be developed to address specific learning objectives, while not preventing other learning points from emerging. Buying a patient simulator, finding a volunteer to act as the patient, or even obtaining ready-made scenarios from another simulation…

Becoming a High-Fidelity--"Super"--Imitator: What Are the Contributions of Social and Individual Learning?

ERIC Educational Resources Information Center

Subiaul, Francys; Patterson, Eric M.; Schilder, Brian; Renner, Elizabeth; Barr, Rachel

2015-01-01

In contrast to other primates, human children's imitation performance goes from low to high fidelity soon after infancy. Are such changes associated with the development of other forms of learning? We addressed this question by testing 215 children (26-59 months) on two social conditions (imitation, emulation)--involving a demonstration--and two…

Orbit Stability of OSIRIS-REx in the Vicinity of Bennu Using a High-Fidelity Solar Radiation Model

NASA Technical Reports Server (NTRS)

Williams, Trevor W.; Hughes, Kyle M.; Mashiku, Alinda K.; Longuski, James M.

2015-01-01

Solar radiation pressure is one of the largest perturbing forces on the OSIRISRex trajectory as it orbits the asteroid Bennu. In this work, we investigate how forces due to solar radiation perturb the OSIRIS-REx trajectory in a high-fidelity model. The model accounts for Bennu's non-spherical gravity field, third-body gravity forces from the Sun and Jupiter, as well as solar radiation forces acting on a simplified spacecraft model. Such high-fidelity simulations indicate significant solar radiation pressure perturbations from the nominal orbit. Modifications to the initial design of the nominal orbit are found using a variation of parameters approach that reduce the perturbation in eccentricity by a factor of one-half.

Fast, high-fidelity readout of multiple qubits

NASA Astrophysics Data System (ADS)

Bronn, N. T.; Abdo, B.; Inoue, K.; Lekuch, S.; Córcoles, A. D.; Hertzberg, J. B.; Takita, M.; Bishop, L. S.; Gambetta, J. M.; Chow, J. M.

2017-05-01

Quantum computing requires a delicate balance between coupling quantum systems to external instruments for control and readout, while providing enough isolation from sources of decoherence. Circuit quantum electrodynamics has been a successful method for protecting superconducting qubits, while maintaining the ability to perform readout [1, 2]. Here, we discuss improvements to this method that allow for fast, high-fidelity readout. Specifically, the integration of a Purcell filter, which allows us to increase the resonator bandwidth for fast readout, the incorporation of a Josephson parametric converter, which enables us to perform high-fidelity readout by amplifying the readout signal while adding the minimum amount of noise required by quantum mechanics, and custom control electronics, which provide us with the capability of fast decision and control.

High-fidelity cluster state generation for ultracold atoms in an optical lattice.

PubMed

Inaba, Kensuke; Tokunaga, Yuuki; Tamaki, Kiyoshi; Igeta, Kazuhiro; Yamashita, Makoto

2014-03-21

We propose a method for generating high-fidelity multipartite spin entanglement of ultracold atoms in an optical lattice in a short operation time with a scalable manner, which is suitable for measurement-based quantum computation. To perform the desired operations based on the perturbative spin-spin interactions, we propose to actively utilize the extra degrees of freedom (DOFs) usually neglected in the perturbative treatment but included in the Hubbard Hamiltonian of atoms, such as, (pseudo-)charge and orbital DOFs. Our method simultaneously achieves high fidelity, short operation time, and scalability by overcoming the following fundamental problem: enhancing the interaction strength for shortening the operation time breaks the perturbative condition of the interaction and inevitably induces unwanted correlations among the spin and extra DOFs.

Long lifetime and high-fidelity quantum memory of photonic polarization qubit by lifting zeeman degeneracy.

PubMed

Xu, Zhongxiao; Wu, Yuelong; Tian, Long; Chen, Lirong; Zhang, Zhiying; Yan, Zhihui; Li, Shujing; Wang, Hai; Xie, Changde; Peng, Kunchi

2013-12-13

Long-lived and high-fidelity memory for a photonic polarization qubit (PPQ) is crucial for constructing quantum networks. We present a millisecond storage system based on electromagnetically induced transparency, in which a moderate magnetic field is applied on a cold-atom cloud to lift Zeeman degeneracy and, thus, the PPQ states are stored as two magnetic-field-insensitive spin waves. Especially, the influence of magnetic-field-sensitive spin waves on the storage performances is almost totally avoided. The measured average fidelities of the polarization states are 98.6% at 200  μs and 78.4% at 4.5 ms, respectively.

Investigating variations in implementation fidelity of an organizational-level occupational health intervention.

PubMed

Augustsson, Hanna; von Thiele Schwarz, Ulrica; Stenfors-Hayes, Terese; Hasson, Henna

2015-06-01

The workplace has been suggested as an important arena for health promotion, but little is known about how the organizational setting influences the implementation of interventions. The aims of this study are to evaluate implementation fidelity in an organizational-level occupational health intervention and to investigate possible explanations for variations in fidelity between intervention units. The intervention consisted of an integration of health promotion, occupational health and safety, and a system for continuous improvements (Kaizen) and was conducted in a quasi-experimental design at a Swedish hospital. Implementation fidelity was evaluated with the Conceptual Framework for Implementation Fidelity and implementation factors used to investigate variations in fidelity with the Framework for Evaluating Organizational-level Interventions. A multi-method approach including interviews, Kaizen notes, and questionnaires was applied. Implementation fidelity differed between units even though the intervention was introduced and supported in the same way. Important differences in all elements proposed in the model for evaluating organizational-level interventions, i.e., context, intervention, and mental models, were found to explain the differences in fidelity. Implementation strategies may need to be adapted depending on the local context. Implementation fidelity, as well as pre-intervention implementation elements, is likely to affect the implementation success and needs to be assessed in intervention research. The high variation in fidelity across the units indicates the need for adjustments to the type of designs used to assess the effects of interventions. Thus, rather than using designs that aim to control variation, it may be necessary to use those that aim at exploring and explaining variation, such as adapted study designs.

Site fidelity, territory fidelity, and natal philopatry in Willow Flycatchers (Empidonax traillii)

USGS Publications Warehouse

Sedgwick, James A.

2004-01-01

I investigated the causes and consequences of adult breeding-site fidelity, territory fidelity, and natal philopatry in Willow Flycatchers (Empidonax traillii) in southeastern Oregon over a 10-year period, testing the general hypothesis that fidelity and dispersal distances are influenced by previous breeding performance. Willow Flycatchers adhered to the generally observed tendencies of passerine birds for low natal philopatry and high breedingsite fidelity. Site fidelity (return to the study area) of adult males (52.0%) and females (51.3%), and median dispersal distances between seasons (16 m vs. 19 m) were similar. Previous breeding performance and residency (age-experience), but not study-site quality, explained site fidelity in females. Site fidelity of females rearing 4–5 young (64.4%) exceeded that of unsuccessful females (40.0%), breeding dispersal was less (successful: 15 m; unsuccessful: 33 m), and novice residents were more site-faithful than former residents. Probability of site fidelity was higher for previously successful females (odds ratio = 4.76), those with greater seasonal fecundity (odds ratio = 1.58), novice residents (odds ratio = 1.41), and unparasitized females (odds ratio = 2.76). Male site fidelity was not related to residency, site quality, or previous breeding performance. Territory fidelity (return to the previous territory) in females was best explained by previous breeding performance, but not by site quality or residency. Previously successful females were more likely to return to their territory of the previous season than either unsuccessful (odds ratio = 14.35) or parasitized birds (odds ratio = 6.38). Male territory fidelity was not related to residency, site quality, or previous breeding performance. Natal philopatry was low (7.8%) and similar for males and females. Site quality appeared to influence philopatry, given that no birds reared at a low-quality study site returned there to breed, and birds reared there dispersed farther than birds reared at two other study sites. My results partially support the hypothesis that site fidelity is an adaptive response: (1) previously successful females that switched territories underperformed those that did not switch (P = 0.01); and (2) previously unsuccessful females that switched territories outperformed those that did not switch, but not significantly (P = 0.22).

Multifamily Group Psychoeducation in New York State: Implementation and Fidelity Outcomes.

PubMed

Kealey, Edith M; Leckman-Westin, Emily; Jewell, Thomas C; Finnerty, Molly T

2015-11-01

The study examined implementation outcomes from a large state initiative to support dissemination of multifamily group (MFG) psychoeducation in outpatient mental health settings. Thirty-one sites participated in the project. Baseline training in the MFG model was followed by monthly expert consultation delivered in either a group (16 sites) or individual format (15 sites). Research staff assessed fidelity to the MFG model by telephone at baseline and 12, 18, and 24 months and documented time to completion of three key milestones: holding a family joining session, a family educational workshop, and an MFG meeting. Intent-to-train analyses found that 12 sites (39%) achieved high fidelity to the MFG model, and 20 (65%) achieved moderate or high fidelity. Mean scores on the Family Psychoeducation Fidelity Assessment Scale increased over time. Twenty-five sites (81%) conducted at least one joining session, and 20 (65%) conducted at least one MFG. Mean±SD time from baseline to the first group was 11.75±4.78 months. Programs that held the first joining session within four to 12 months after training were significantly more likely than programs that did not to conduct a group (p<.05). No significant differences were found by consultation format. Implementation of moderate- to high-fidelity MFG programs in routine outpatient mental health settings is feasible. Sites that moved very quickly or very slowly in early implementation stages were less likely to be successful in conducting an MFG. More research on the efficiency and effectiveness of consultation formats is needed to guide future implementation efforts.

Use of VR Technology and Passive Haptics for MANPADS Training System

DTIC Science & Technology

2017-09-01

this setup also does not offer a variety of challenging scenarios needed for good training as the aircraft are mostly flying in landing or take-off... customized high-fidelity immersive training facilities are limited. Moreover, low trainee throughput from such high-end facilities is an ongoing obstacle...opportunities allow few operators to fire during live exercises. Simulation training is effective, but customized high-fidelity immersive training

Development of Adaptive Model Refinement (AMoR) for Multiphysics and Multifidelity Problems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turinsky, Paul

This project investigated the development and utilization of Adaptive Model Refinement (AMoR) for nuclear systems simulation applications. AMoR refers to utilization of several models of physical phenomena which differ in prediction fidelity. If the highest fidelity model is judged to always provide or exceeded the desired fidelity, than if one can determine the difference in a Quantity of Interest (QoI) between the highest fidelity model and lower fidelity models, one could utilize the fidelity model that would just provide the magnitude of the QoI desired. Assuming lower fidelity models require less computational resources, in this manner computational efficiency can bemore » realized provided the QoI value can be accurately and efficiently evaluated. This work utilized Generalized Perturbation Theory (GPT) to evaluate the QoI, by convoluting the GPT solution with the residual of the highest fidelity model determined using the solution from lower fidelity models. Specifically, a reactor core neutronics problem and thermal-hydraulics problem were studied to develop and utilize AMoR. The highest fidelity neutronics model was based upon the 3D space-time, two-group, nodal diffusion equations as solved in the NESTLE computer code. Added to the NESTLE code was the ability to determine the time-dependent GPT neutron flux. The lower fidelity neutronics model was based upon the point kinetics equations along with utilization of a prolongation operator to determine the 3D space-time, two-group flux. The highest fidelity thermal-hydraulics model was based upon the space-time equations governing fluid flow in a closed channel around a heat generating fuel rod. The Homogenous Equilibrium Mixture (HEM) model was used for the fluid and Finite Difference Method was applied to both the coolant and fuel pin energy conservation equations. The lower fidelity thermal-hydraulic model was based upon the same equations as used for the highest fidelity model but now with coarse spatial meshing, corrected somewhat by employing effective fuel heat conduction values. The effectiveness of switching between the highest fidelity model and lower fidelity model as a function of time was assessed using the neutronics problem. Based upon work completed to date, one concludes that the time switching is effective in annealing out differences between the highest and lower fidelity solutions. The effectiveness of using a lower fidelity GPT solution, along with a prolongation operator, to estimate the QoI was also assessed. The utilization of a lower fidelity GPT solution was done in an attempt to avoid the high computational burden associated with solving for the highest fidelity GPT solution. Based upon work completed to date, one concludes that the lower fidelity adjoint solution is not sufficiently accurate with regard to estimating the QoI; however, a formulation has been revealed that may provide a path for addressing this shortcoming.« less

Long Live Love+: evaluation of the implementation of an online school-based sexuality education program in the Netherlands.

PubMed

van Lieshout, Sanne; Mevissen, Fraukje; de Waal, Esri; Kok, Gerjo

2017-06-01

Schools are a common setting for adolescents to receive health education, but implementation of these programs with high levels of completeness and fidelity is not self-evident. Programs that are only partially implemented (completeness) or not implemented as instructed (fidelity) are unlikely to be effective. Therefore, it is important to identify which determinants affect completeness and fidelity of program implementation. As part of the launch of Long Live Love+ (LLL+), an online school-based sexuality education program for adolescents aged 15-17, we performed a process evaluation among teachers and students to measure the levels of completeness and fidelity, identify factors influencing teachers' implementation, and to evaluate the students' response. Sixteen Biology teachers from nine secondary schools throughout the Netherlands who implemented LLL+ were interviewed and 60 students participated in 13 focus group discussions. Results showed that teachers' completeness ranged between 22-100% (M = 75%). Fidelity was high, but many teachers added elements. Teachers and students enjoyed LLL+, particularly the diversity in the exercises and its interactive character. The most important factors that influenced implementation were time and organizational constraints, lack of awareness on the impact of completeness and fidelity, and student response. These factors should be taken into account when developing school-based prevention programs. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Fidelity assessment of a UH-60A simulation on the NASA Ames vertical motion simulator

NASA Technical Reports Server (NTRS)

Atencio, Adolph, Jr.

1993-01-01

Helicopter handling qualities research requires that a ground-based simulation be a high-fidelity representation of the actual helicopter, especially over the frequency range of the investigation. This experiment was performed to assess the current capability to simulate the UH-60A Black Hawk helicopter on the Vertical Motion Simulator (VMS) at NASA Ames, to develop a methodology for assessing the fidelity of a simulation, and to find the causes for lack of fidelity. The approach used was to compare the simulation to the flight vehicle for a series of tasks performed in flight and in the simulator. The results show that subjective handling qualities ratings from flight to simulator overlap, and the mathematical model matches the UH-60A helicopter very well over the range of frequencies critical to handling qualities evaluation. Pilot comments, however, indicate a need for improvement in the perceptual fidelity of the simulation in the areas of motion and visual cuing. The methodology used to make the fidelity assessment proved useful in showing differences in pilot work load and strategy, but additional work is needed to refine objective methods for determining causes of lack of fidelity.

Unbiased multi-fidelity estimate of failure probability of a free plane jet

NASA Astrophysics Data System (ADS)

Marques, Alexandre; Kramer, Boris; Willcox, Karen; Peherstorfer, Benjamin

2017-11-01

Estimating failure probability related to fluid flows is a challenge because it requires a large number of evaluations of expensive models. We address this challenge by leveraging multiple low fidelity models of the flow dynamics to create an optimal unbiased estimator. In particular, we investigate the effects of uncertain inlet conditions in the width of a free plane jet. We classify a condition as failure when the corresponding jet width is below a small threshold, such that failure is a rare event (failure probability is smaller than 0.001). We estimate failure probability by combining the frameworks of multi-fidelity importance sampling and optimal fusion of estimators. Multi-fidelity importance sampling uses a low fidelity model to explore the parameter space and create a biasing distribution. An unbiased estimate is then computed with a relatively small number of evaluations of the high fidelity model. In the presence of multiple low fidelity models, this framework offers multiple competing estimators. Optimal fusion combines all competing estimators into a single estimator with minimal variance. We show that this combined framework can significantly reduce the cost of estimating failure probabilities, and thus can have a large impact in fluid flow applications. This work was funded by DARPA.

Time to unravel the conceptual confusion of authenticity and fidelity and their contribution to learning within simulation-based nurse education. A discussion paper.

PubMed

Bland, Andrew J; Topping, Annie; Tobbell, Jane

2014-07-01

High-fidelity patient simulation is a method of education increasingly utilised by educators of nursing to provide authentic learning experiences. Fidelity and authenticity, however, are not conceptually equivalent. Whilst fidelity is important when striving to replicate a life experience such as clinical practice, authenticity can be produced with low fidelity. A challenge for educators of undergraduate nursing is to ensure authentic representation of the clinical situation which is a core component for potential success. What is less clear is the relationship between fidelity and authenticity in the context of simulation based learning. Authenticity does not automatically follow fidelity and as a result, educators of nursing cannot assume that embracing the latest technology-based educational tools will in isolation provide a learning environment perceived authentic by the learner. As nursing education programmes increasingly adopt simulators that offer the possibility of representing authentic real world situations, there is an urgency to better articulate and understand the terms fidelity and authenticity. Without such understanding there is a real danger that simulation as a teaching and learning resource in nurse education will never reach its potential and be misunderstood, creating a potential barrier to learning. This paper examines current literature to promote discussion within nurse education, concluding that authenticity in the context of simulation-based learning is complex, relying on far more than engineered fidelity. Copyright © 2014 Elsevier Ltd. All rights reserved.

High Fidelity Measurement and Modeling of Interactions between Acoustics and Heat Release in Highly-Compact, High-Pressure Flames

DTIC Science & Technology

2016-05-24

experimental data. However, the time and length scales, and energy deposition rates in the canonical laboratory flames that have been studied over the...is to obtain high-fidelity experimental data critically needed to validate research codes at relevant conditions, and to develop systematic and...validated with experimental data. However, the time and length scales, and energy deposition rates in the canonical laboratory flames that have been

Gaze entropy reflects surgical task load.

PubMed

Di Stasi, Leandro L; Diaz-Piedra, Carolina; Rieiro, Héctor; Sánchez Carrión, José M; Martin Berrido, Mercedes; Olivares, Gonzalo; Catena, Andrés

2016-11-01

Task (over-)load imposed on surgeons is a main contributing factor to surgical errors. Recent research has shown that gaze metrics represent a valid and objective index to asses operator task load in non-surgical scenarios. Thus, gaze metrics have the potential to improve workplace safety by providing accurate measurements of task load variations. However, the direct relationship between gaze metrics and surgical task load has not been investigated yet. We studied the effects of surgical task complexity on the gaze metrics of surgical trainees. We recorded the eye movements of 18 surgical residents, using a mobile eye tracker system, during the performance of three high-fidelity virtual simulations of laparoscopic exercises of increasing complexity level: Clip Applying exercise, Cutting Big exercise, and Translocation of Objects exercise. We also measured performance accuracy and subjective rating of complexity. Gaze entropy and velocity linearly increased with increased task complexity: Visual exploration pattern became less stereotyped (i.e., more random) and faster during the more complex exercises. Residents performed better the Clip Applying exercise and the Cutting Big exercise than the Translocation of Objects exercise and their perceived task complexity differed accordingly. Our data show that gaze metrics are a valid and reliable surgical task load index. These findings have potential impacts to improve patient safety by providing accurate measurements of surgeon task (over-)load and might provide future indices to assess residents' learning curves, independently of expensive virtual simulators or time-consuming expert evaluation.

Application of the "see one, do one, teach one" concept in surgical training.

PubMed

Kotsis, Sandra V; Chung, Kevin C

2013-05-01

The traditional method of teaching in surgery is known as "see one, do one, teach one." However, many have argued that this method is no longer applicable, mainly because of concerns for patient safety. The purpose of this article is to show that the basis of the traditional teaching method is still valid in surgical training if it is combined with various adult learning principles. The authors reviewed literature regarding the history of the formation of the surgical residency program, adult learning principles, mentoring, and medical simulation. The authors provide examples for how these learning techniques can be incorporated into a surgical resident training program. The surgical residency program created by Dr. William Halsted remained virtually unchanged until recently with reductions in resident work hours and changes to a competency-based training system. Such changes have reduced the teaching time between attending physicians and residents. Learning principles such as experience, observation, thinking, and action and deliberate practice can be used to train residents. Mentoring is also an important aspect in teaching surgical technique. The authors review the different types of simulators-standardized patients, virtual reality applications, and high-fidelity mannequin simulators-and the advantages and disadvantages of using them. The traditional teaching method of "see one, do one, teach one" in surgical residency programs is simple but still applicable. It needs to evolve with current changes in the medical system to adequately train surgical residents and also provide patients with safe, evidence-based care.

Fluid/Structure Interaction Studies of Aircraft Using High Fidelity Equations on Parallel Computers

NASA Technical Reports Server (NTRS)

Guruswamy, Guru; VanDalsem, William (Technical Monitor)

1994-01-01

Abstract Aeroelasticity which involves strong coupling of fluids, structures and controls is an important element in designing an aircraft. Computational aeroelasticity using low fidelity methods such as the linear aerodynamic flow equations coupled with the modal structural equations are well advanced. Though these low fidelity approaches are computationally less intensive, they are not adequate for the analysis of modern aircraft such as High Speed Civil Transport (HSCT) and Advanced Subsonic Transport (AST) which can experience complex flow/structure interactions. HSCT can experience vortex induced aeroelastic oscillations whereas AST can experience transonic buffet associated structural oscillations. Both aircraft may experience a dip in the flutter speed at the transonic regime. For accurate aeroelastic computations at these complex fluid/structure interaction situations, high fidelity equations such as the Navier-Stokes for fluids and the finite-elements for structures are needed. Computations using these high fidelity equations require large computational resources both in memory and speed. Current conventional super computers have reached their limitations both in memory and speed. As a result, parallel computers have evolved to overcome the limitations of conventional computers. This paper will address the transition that is taking place in computational aeroelasticity from conventional computers to parallel computers. The paper will address special techniques needed to take advantage of the architecture of new parallel computers. Results will be illustrated from computations made on iPSC/860 and IBM SP2 computer by using ENSAERO code that directly couples the Euler/Navier-Stokes flow equations with high resolution finite-element structural equations.

The Effects of Moderate- and High-Fidelity Patient Simulator Use on Critical Thinking in Associate Degree Nursing Students

ERIC Educational Resources Information Center

Vieck, Jana

2013-01-01

The purpose of this study was to examine the impact of moderate- and high-fidelity patient simulator use on the critical thinking skills of associate degree nursing students. This quantitative study used a quasi-experimental design and the Health Sciences Reasoning Test (HSRT) to evaluate the critical thinking skills of third semester nursing…

Using a High-Fidelity Patient Simulator with First-Year Medical Students to Facilitate Learning of Cardiovascular Function Curves

ERIC Educational Resources Information Center

Harris, David M.; Ryan, Kathleen; Rabuck, Cynthia

2012-01-01

Students are relying on technology for learning more than ever, and educators need to adapt to facilitate student learning. High-fidelity patient simulators (HFPS) are usually reserved for the clinical years of medical education and are geared to improve clinical decision skills, teamwork, and patient safety. Finding ways to incorporate HFPS into…

Modeling of Passive Acoustic Liners from High Fidelity Numerical Simulations

NASA Astrophysics Data System (ADS)

Ferrari, Marcello do Areal Souto

Noise reduction in aviation has been an important focus of study in the last few decades. One common solution is setting up acoustic liners in the internal walls of the engines. However, measurements in the laboratory with liners are expensive and time consuming. The present work proposes a nonlinear physics-based time domain model to predict the acoustic behavior of a given liner in a defined flow condition. The parameters of the model are defined by analysis of accurate numerical solutions of the flow obtained from a high-fidelity numerical code. The length of the cavity is taken into account by using an analytical procedure to account for internal reflections in the interior of the cavity. Vortices and jets originated from internal flow separations are confirmed to be important mechanisms of sound absorption, which defines the overall efficiency of the liner. Numerical simulations at different frequency, geometry and sound pressure level are studied in detail to define the model parameters. Comparisons with high-fidelity numerical simulations show that the proposed model is accurate, robust, and can be used to define a boundary condition simulating a liner in a high-fidelity code.

Comparison of Low-Thrust Control Laws for Application in Planetocentric Space

NASA Technical Reports Server (NTRS)

Falck, Robert D.; Sjauw, Waldy K.; Smith, David A.

2014-01-01

Recent interest at NASA for the application of solar electric propulsion for the transfer of significant payloads in cislunar space has led to the development of high-fidelity simulations of such missions. With such transfers involving transfer times on the order of months, simulation time can be significant. In the past, the examination of such missions typically began with the use of lower-fidelity trajectory optimization tools such as SEPSPOT to develop and tune guidance laws which delivered optimal or near- optimal trajectories, where optimal is generally defined as minimizing propellant expenditure or time of flight. The transfer of these solutions to a high-fidelity simulation is typically an iterative process whereby the initial solution may nearly, but not precisely, meet mission objectives. Further tuning of the guidance algorithm is typically necessary when accounting for high-fidelity perturbations such as those due to more detailed gravity models, secondary-body effects, solar radiation pressure, etc. While trajectory optimization is a useful method for determining optimal performance metrics, algorithms which deliver nearly optimal performance with minimal tuning are an attractive alternative.

An adaptive sampling method for variable-fidelity surrogate models using improved hierarchical kriging

NASA Astrophysics Data System (ADS)

Hu, Jiexiang; Zhou, Qi; Jiang, Ping; Shao, Xinyu; Xie, Tingli

2018-01-01

Variable-fidelity (VF) modelling methods have been widely used in complex engineering system design to mitigate the computational burden. Building a VF model generally includes two parts: design of experiments and metamodel construction. In this article, an adaptive sampling method based on improved hierarchical kriging (ASM-IHK) is proposed to refine the improved VF model. First, an improved hierarchical kriging model is developed as the metamodel, in which the low-fidelity model is varied through a polynomial response surface function to capture the characteristics of a high-fidelity model. Secondly, to reduce local approximation errors, an active learning strategy based on a sequential sampling method is introduced to make full use of the already required information on the current sampling points and to guide the sampling process of the high-fidelity model. Finally, two numerical examples and the modelling of the aerodynamic coefficient for an aircraft are provided to demonstrate the approximation capability of the proposed approach, as well as three other metamodelling methods and two sequential sampling methods. The results show that ASM-IHK provides a more accurate metamodel at the same simulation cost, which is very important in metamodel-based engineering design problems.

Creation of a High-fidelity, Low-cost Pediatric Skull Fracture Ultrasound Phantom.

PubMed

Soucy, Zachary P; Mills, Lisa; Rose, John S; Kelley, Kenneth; Ramirez, Francisco; Kuppermann, Nathan

2015-08-01

Over the past decade, point-of-care ultrasound has become a common tool used for both procedures and diagnosis. Developing high-fidelity phantoms is critical for training in new and novel point-of-care ultrasound applications. Detecting skull fractures on ultrasound imaging in the younger-than-2-year-old patient is an emerging area of point-of-care ultrasound research. Identifying a skull fracture on ultrasound imaging in this age group requires knowledge of the appearance and location of sutures to distinguish them from fractures. There are currently no commercially available pediatric skull fracture models. We outline a novel approach to building a cost-effective, simple, high-fidelity pediatric skull fracture phantom to meet a unique training requirement. © 2015 by the American Institute of Ultrasound in Medicine.

Measuring Implementation Fidelity in a Community-Based Parenting Intervention

PubMed Central

Breitenstein, Susan M.; Fogg, Louis; Garvey, Christine; Hill, Carri; Resnick, Barbara; Gross, Deborah

2012-01-01

Background Establishing the feasibility and validity of implementation fidelity monitoring strategies is an important methodological step in implementing evidence-based interventions on a large scale. Objectives The objective of the study was to examine the reliability and validity of the Fidelity Checklist, a measure designed to assess group leader adherence and competence delivering a parent training intervention (the Chicago Parent Program) in child care centers serving low-income families. Method The sample included 9 parent groups (12 group sessions each), 12 group leaders, and 103 parents. Independent raters reviewed 106 audiotaped parent group sessions and coded group leaders’ fidelity on the Adherence and Competence Scales of the Fidelity Checklist. Group leaders completed self-report adherence checklists and a measure of parent engagement in the intervention. Parents completed measures of consumer satisfaction and child behavior. Results High interrater agreement (Adherence Scale = 94%, Competence Scale = 85%) and adequate intraclass correlation coefficients (Adherence Scale = .69, Competence Scale = .91) were achieved for the Fidelity Checklist. Group leader adherence changed over time, but competence remained stable. Agreement between group leader self-report and independent ratings on the Adherence Scale was 85%; disagreements were more frequently due to positive bias in group leader self-report. Positive correlations were found between group leader adherence and parent attendance and engagement in the intervention and between group leader competence and parent satisfaction. Although child behavior problems improved, improvements were not related to fidelity. Discussion The results suggest that the Fidelity Checklist is a feasible, reliable, and valid measure of group leader implementation fidelity in a group-based parenting intervention. Future research will be focused on testing the Fidelity Checklist with diverse and larger samples and generalizing to other group-based interventions using a similar intervention model. PMID:20404777

Data fusion and photometric restoration

NASA Astrophysics Data System (ADS)

Pirzkal, Norbert; Hook, Richard N.

2001-11-01

The current generation of 8-10m optical ground-based telescopes have a symbiotic relationship with space telescopes. For direct imaging in the optical the former can collect photons relatively cheaply but the latter can still achieve, even in the era of adaptive optics, significantly higher spatial resolution, point-spread function stability and astrometric fidelity over fields of a few arcminutes. The large archives of HST imaging already in place, when combined with the ease of access to ground-based data afforded by the virtual observatory currently under development, will make space-ground data fusion a powerful tool for the future. We describe a photometric image restoration method that we have developed which allows the efficient and accurate use of high-resolution space imaging of crowded fields to extract high quality photometry from very crowded ground-based images. We illustrate the method using HST and ESO VLT/FORS imaging of a globular cluster and demonstrate quantitatively the photometric measurements quality that can achieved using the data fusion approach instead of just using data from just one telescope. This method can handle most of the common difficulties encountered when attempting this problem such as determining the geometric mapping to the requisite precision, deriving the PSF and the background.

Sparse-view photoacoustic tomography using virtual parallel-projections and spatially adaptive filtering

NASA Astrophysics Data System (ADS)

Wang, Yihan; Lu, Tong; Wan, Wenbo; Liu, Lingling; Zhang, Songhe; Li, Jiao; Zhao, Huijuan; Gao, Feng

2018-02-01

To fully realize the potential of photoacoustic tomography (PAT) in preclinical and clinical applications, rapid measurements and robust reconstructions are needed. Sparse-view measurements have been adopted effectively to accelerate the data acquisition. However, since the reconstruction from the sparse-view sampling data is challenging, both of the effective measurement and the appropriate reconstruction should be taken into account. In this study, we present an iterative sparse-view PAT reconstruction scheme where a virtual parallel-projection concept matching for the proposed measurement condition is introduced to help to achieve the "compressive sensing" procedure of the reconstruction, and meanwhile the spatially adaptive filtering fully considering the a priori information of the mutually similar blocks existing in natural images is introduced to effectively recover the partial unknown coefficients in the transformed domain. Therefore, the sparse-view PAT images can be reconstructed with higher quality compared with the results obtained by the universal back-projection (UBP) algorithm in the same sparse-view cases. The proposed approach has been validated by simulation experiments, which exhibits desirable performances in image fidelity even from a small number of measuring positions.

Progress in virtual reality simulators for surgical training and certification.

PubMed

de Visser, Hans; Watson, Marcus O; Salvado, Olivier; Passenger, Joshua D

2011-02-21

There is increasing evidence that educating trainee surgeons by simulation is preferable to traditional operating-room training methods with actual patients. Apart from reducing costs and risks to patients, training by simulation can provide some unique benefits, such as greater control over the training procedure and more easily defined metrics for assessing proficiency. Virtual reality (VR) simulators are now playing an increasing role in surgical training. However, currently available VR simulators lack the fidelity to teach trainees past the novice-to-intermediate skills level. Recent technological developments in other industries using simulation, such as the games and entertainment and aviation industries, suggest that the next generation of VR simulators should be suitable for training, maintenance and certification of advanced surgical skills. To be effective as an advanced surgical training and assessment tool, VR simulation needs to provide adequate and relevant levels of physical realism, case complexity and performance assessment. Proper validation of VR simulators and an increased appreciation of their value by the medical profession are crucial for them to be accepted into surgical training curricula.

An Enriched Shell Element for Delamination Simulation in Composite Laminates

NASA Technical Reports Server (NTRS)

McElroy, Mark

2015-01-01

A formulation is presented for an enriched shell finite element capable of delamination simulation in composite laminates. The element uses an adaptive splitting approach for damage characterization that allows for straightforward low-fidelity model creation and a numerically efficient solution. The Floating Node Method is used in conjunction with the Virtual Crack Closure Technique to predict delamination growth and represent it discretely at an arbitrary ply interface. The enriched element is verified for Mode I delamination simulation using numerical benchmark data. After determining important mesh configuration guidelines for the vicinity of the delamination front in the model, a good correlation was found between the enriched shell element model results and the benchmark data set.

Replication fidelity improvement of PMMA microlens array based on weight evaluation and optimization

NASA Astrophysics Data System (ADS)

Jiang, Bing-yan; Shen, Long-jiang; Peng, Hua-jiang; Yin, Xiang-lin

2007-12-01

High replication fidelity is a prerequisite of high quality plastic microlens array in injection molding. But, there's not an economical and practical method to evaluate and improve the replication fidelity until now. Based on part weight evaluation and optimization, this paper presents a new method of replication fidelity improvement. Firstly, a simplified analysis model of PMMA micro columns arrays (5×16) with 200μm diameter was set up. And then, Flow (3D) module of Moldflow MPI6.0 based on Navier-Stokes equations was used to calculate the weight of the micro columns arrays in injection molding. The effects of processing parameters (melt temperature, mold temperature, injection time, packing pressure and packing time) on the part weight were investigated in the simulations. The simulation results showed that the mold temperature and the injection time have important effects on the filling of micro columns; the optimal mold temperature and injection time for better replication fidelity could be determined by the curves of mold temperature vs part weight and injection time vs part weight. At last, the effects of processing parameters on part weight of micro columns array were studied experimentally. The experimental results showed that the increase of melt temperature and mold temperature can make the packing pressure transfer to micro cavity more effectively through runner system, and increase the part weight. From the observation results of the image measuring apparatus, it was discovered that the higher the part weight, the better the filling of the microstructures. In conclusion, part weight can be used to evaluate the replication fidelity of micro-feature structured parts primarily; which is an economical and practical method to improve the replication fidelity of microlens arrays based on weight evaluation and optimization.

Housing first on a large scale: Fidelity strengths and challenges in the VA's HUD-VASH program.

PubMed

Kertesz, Stefan G; Austin, Erika L; Holmes, Sally K; DeRussy, Aerin J; Van Deusen Lukas, Carol; Pollio, David E

2017-05-01

Housing First (HF) combines permanent supportive housing and supportive services for homeless individuals and removes traditional treatment-related preconditions for housing entry. There has been little research describing strengths and shortfalls of HF implementation outside of research demonstration projects. The U.S. Department of Veterans Affairs (VA) has transitioned to an HF approach in a supportive housing program serving over 85,000 persons. This offers a naturalistic window to study fidelity when HF is adopted on a large scale. We operationalized HF into 20 criteria grouped into 5 domains. We assessed 8 VA medical centers twice (1 year apart), scoring each criterion using a scale ranging from 1 ( low fidelity ) to 4 ( high fidelity ). There were 2 HF domains (no preconditions and rapidly offering permanent housing) for which high fidelity was readily attained. There was uneven progress in prioritizing the most vulnerable clients for housing support. Two HF domains (sufficient supportive services and a modern recovery philosophy) had considerably lower fidelity. Interviews suggested that operational issues such as shortfalls in staffing and training likely hindered performance in these 2 domains. In this ambitious national HF program, the largest to date, we found substantial fidelity in focusing on permanent housing and removal of preconditions to housing entry. Areas of concern included the adequacy of supportive services and adequacy in deployment of a modern recovery philosophy. Under real-world conditions, large-scale implementation of HF is likely to require significant additional investment in client service supports to assure that results are concordant with those found in research studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

High-Fidelity Design of Multimodal Restorative Interventions in Gulf War Illness

DTIC Science & Technology

2017-10-01

Bockmayr A, Klarner H, Siebert H. Time series dependent analysis of unparametrized Thomas networks. IEEE/ACM Transactions on Computational Biology and...Award Number: W81XWH-15-1-0582 TITLE:High-Fidelity Design of Multimodal Restorative Interventions in Gulf War Illness PRINCIPAL INVESTIGATOR...not be construed as an official Department of the Army position, policy or decision unless so designated by other documentation. REPORT

Effects of High Fidelity Simulation on Knowledge Acquisition, Self-Confidence, and Satisfaction with Baccalaureate Nursing Students Using the Solomon-Four Research Design

ERIC Educational Resources Information Center

Hall, Rachel Mattson

2013-01-01

High Fidelity Simulation is a teaching strategy that is becoming well-entrenched in the world of nursing education and is rapidly expanding due to the challenges and demands of the health care environment. The problem addressed in this study is the conflicting research results regarding the effectiveness of HFS for students' knowledge acquisition…

Effects of High-Fidelity Human Patient Simulation Experience on Self-Efficacy, Motivation and Learning of First Semester Associate Degree Nursing Students

ERIC Educational Resources Information Center

Kuznar, Kathleen A.

2009-01-01

One of the newest methodologies in nursing education is high-fidelity human patient simulation (HPS). Many nursing educators have embraced the method as it offers a strategy to facilitate cognitive, affective, and psychomotor outcomes. Despite their popularity, however, HPS systems are costly and, in an era of cost containment and tuition…

SITE FIDELITY AND EPHEMERAL HABITAT OCCUPANCY: NORTHERN WATERTHRUSH USE OF PUERTO RICAN BLACK MANGROVES DURING THE NONBREEDING SEASON.

Treesearch

LEONARD REITSMA; PAMELA HUNT; SHERMAN L. BURSON III; BENJAMIN B. STEELE

2002-01-01

We studied the dispersion of Northern Waterthrushes (Seiurus novaboracensis) in southwestern Puerto Rico during four nonbreeding seasons, 1996–1999. Densities were high (up to 13 birds/ha) on a 3-ha mature black mangrove (Avicennia germinans) study plot, but were significantly lower during periods of high water levels. Individuals exhibited site fidelity within and...

Comparison of Satisfaction, Self-Confidence, and Engagement of Baccalaureate Nursing Students Using Defined Observational Roles and Expectations versus Traditional Role Assignments in High Fidelity Simulation and Debriefing

ERIC Educational Resources Information Center

Howard, Sheri

2017-01-01

The purpose of this study is to compare satisfaction, self-confidence, and engagement of baccalaureate nursing students using defined observational roles and expectations versus traditional observer role assignments in high fidelity simulation and debriefing and to evaluate student perceptions of these constructs. The NLN/Jeffries Simulation…

An Evaluation of Immediate Outcomes and Fidelity of a Drug Abuse Prevention Program in Continuation High Schools: Project towards No Drug Abuse (TND)

ERIC Educational Resources Information Center

Lisha, Nadra E.; Sun, Ping; Rohrbach, Louise A.; Spruijt-Metz, Donna; Unger, Jennifer B.; Sussman, Steve

2012-01-01

The present study provides an implementation fidelity, process, and immediate outcomes evaluation of Project Towards No Drug Abuse (TND), a drug prevention program targeting continuation high school youth (n = 1426) at risk for drug abuse. A total of 24 schools participated in three randomized conditions: TND Only, TND and motivational…

Motivation and Technological Readiness in the Use of High-Fidelity Simulation: A Descriptive Comparative Study of Nurse Educators

ERIC Educational Resources Information Center

Duvall, Judy Jo

2012-01-01

There are many driving forces to increase the use of high-fidelity simulation (HFS) in nursing education, as well as many factors that may influence the implementation of this teaching strategy. These include the motivation of nurse educators to use HFS, the technological readiness of nurse educators to use HFS and the changing demographics of the…

Evaluation of high fidelity patient simulator in assessment of performance of anaesthetists.

PubMed

Weller, J M; Bloch, M; Young, S; Maze, M; Oyesola, S; Wyner, J; Dob, D; Haire, K; Durbridge, J; Walker, T; Newble, D

2003-01-01

There is increasing emphasis on performance-based assessment of clinical competence. The High Fidelity Patient Simulator (HPS) may be useful for assessment of clinical practice in anaesthesia, but needs formal evaluation of validity, reliability, feasibility and effect on learning. We set out to assess the reliability of a global rating scale for scoring simulator performance in crisis management. Using a global rating scale, three judges independently rated videotapes of anaesthetists in simulated crises in the operating theatre. Five anaesthetists then independently rated subsets of these videotapes. There was good agreement between raters for medical management, behavioural attributes and overall performance. Agreement was high for both the initial judges and the five additional raters. Using a global scale to assess simulator performance, we found good inter-rater reliability for scoring performance in a crisis. We estimate that two judges should provide a reliable assessment. High fidelity simulation should be studied further for assessing clinical performance.

Enhanced fidelity of an educational intervention on skin self-examination through surveillance and standardization

PubMed Central

Gaber, Rikki; Mallett, Kimberly A.; Hultgren, Brittney; Turrisi, Rob; Gilbertsen, Margaret L.; Martini, Mary C.; Robinson, June K.

2014-01-01

Background Melanoma can metastasize but is often successfully treated when discovered in an early stage. Melanoma patients and their skin check partners can learn skin self-examination (SSE) skills and these skills can be improved by practice. The purpose of this study is to determine the degree of fidelity with which educational in-person SSE intervention can be delivered by trained research coordinators to patients at risk of developing another melanoma and their skin check partners. Methods The in-person intervention was performed in two iterations. In phase 1 (2006-2008), the research coordinators were trained to perform the intervention using a written script. In phase 2 (2011-2013), the research coordinators were trained to perform the intervention with a PowerPoint aid. Each research coordinator was individually counseled by one of the authors (KM) to insure standardization and enhance fidelity of intervention delivery. Phase 1 and Phase 2 were compared on 16 fidelity components. Further, Phase 2 fidelity was assessed by comparing mean scores of fidelity across the five research coordinators who delivered the intervention. Results Phase 2, which utilized a PowerPoint aid, was delivered with a higher degree of fidelity compared to phase 1with four fidelity components with significantly higher fidelity than Phase 1: 1) Explained details of melanoma, χ2 (1, n = 199)= 96.31, p < .001, 2) Discussed when to call doctor, χ2 (1, n = 199) = 53.68, p < .001 3) Explained assessment at month 1, χ2 (1, n = 199)= 12.39, p < .01, and 4) Explained assessment at month 2, χ2 (1, n = 199) = 117.75, p < .001. Further, no significant differences on mean fidelity were found across research coordinators in Phase 2. Discussion When using the PowerPoint aide, the research coordinators delivered the intervention with high fidelity (all scores >14) and there were no mean differences in fidelity across research coordinators, indicating consistency in fidelity. This can be attributed to the standardization and cueing that the PowerPoint program offered. Supervision was also a key component in establishing and maintaining fidelity of the patient educational process. This method of intervention delivery enables trained healthcare professionals to deliver an educational intervention in an effective, consistent manner. PMID:25414761

Enhanced fidelity of an educational intervention on skin self-examination through surveillance and standardization.

PubMed

Gaber, Rikki; Mallett, Kimberly A; Hultgren, Brittney; Turrisi, Rob; Gilbertsen, Margaret L; Martini, Mary C; Robinson, June K

2014-01-01

Melanoma can metastasize but is often successfully treated when discovered in an early stage. Melanoma patients and their skin check partners can learn skin self-examination (SSE) skills and these skills can be improved by practice. The purpose of this study is to determine the degree of fidelity with which educational in-person SSE intervention can be delivered by trained research coordinators to patients at risk of developing another melanoma and their skin check partners. The in-person intervention was performed in two iterations. In phase 1 (2006-2008), the research coordinators were trained to perform the intervention using a written script. In phase 2 (2011-2013), the research coordinators were trained to perform the intervention with a PowerPoint aid. Each research coordinator was individually counseled by one of the authors (KM) to insure standardization and enhance fidelity of intervention delivery. Phase 1 and Phase 2 were compared on 16 fidelity components. Further, Phase 2 fidelity was assessed by comparing mean scores of fidelity across the five research coordinators who delivered the intervention. Phase 2, which utilized a PowerPoint aid, was delivered with a higher degree of fidelity compared to phase 1with four fidelity components with significantly higher fidelity than Phase 1: 1) Explained details of melanoma, χ 2 (1, n = 199)= 96.31, p < .001, 2) Discussed when to call doctor, χ 2 (1, n = 199) = 53.68, p < .001 3) Explained assessment at month 1, χ 2 (1, n = 199)= 12.39, p < .01, and 4) Explained assessment at month 2, χ 2 (1, n = 199) = 117.75, p < .001. Further, no significant differences on mean fidelity were found across research coordinators in Phase 2. When using the PowerPoint aide, the research coordinators delivered the intervention with high fidelity (all scores >14) and there were no mean differences in fidelity across research coordinators, indicating consistency in fidelity. This can be attributed to the standardization and cueing that the PowerPoint program offered. Supervision was also a key component in establishing and maintaining fidelity of the patient educational process. This method of intervention delivery enables trained healthcare professionals to deliver an educational intervention in an effective, consistent manner.

Attenuation of Foot-and-Mouth Disease Virus by Engineered Viral Polymerase Fidelity.

PubMed

Rai, Devendra K; Diaz-San Segundo, Fayna; Campagnola, Grace; Keith, Anna; Schafer, Elizabeth A; Kloc, Anna; de Los Santos, Teresa; Peersen, Olve; Rieder, Elizabeth

2017-08-01

Foot-and-mouth disease virus (FMDV) RNA-dependent RNA polymerase (RdRp) (3D pol ) catalyzes viral RNA synthesis. Its characteristic low fidelity and absence of proofreading activity allow FMDV to rapidly mutate and adapt to dynamic environments. In this study, we used the structure of FMDV 3D pol in combination with previously reported results from similar picornaviral polymerases to design point mutations that would alter replication fidelity. In particular, we targeted Trp237 within conserved polymerase motif A because of the low reversion potential inherent in the single UGG codon. Using biochemical and genetic tools, we show that the replacement of tryptophan 237 with phenylalanine imparts higher fidelity, but replacements with isoleucine and leucine resulted in lower-fidelity phenotypes. Viruses containing these W237 substitutions show in vitro growth kinetics and plaque morphologies similar to those of the wild-type (WT) A 24 Cruzeiro strain in BHK cells, and both high- and low-fidelity variants retained fitness during coinfection with the wild-type virus. The higher-fidelity W237F (W237F HF ) mutant virus was more resistant to the mutagenic nucleoside analogs ribavirin and 5-fluorouracil than the WT virus, whereas the lower-fidelity W237I (W237I LF ) and W237L LF mutant viruses exhibited lower ribavirin resistance. Interestingly, the variant viruses showed heterogeneous and slightly delayed growth kinetics in primary porcine kidney cells, and they were significantly attenuated in mouse infection experiments. These data demonstrate, for a single virus, that either increased or decreased RdRp fidelity attenuates virus growth in animals, which is a desirable feature for the development of safer and genetically more stable vaccine candidates. IMPORTANCE Foot-and-mouth disease (FMD) is the most devastating disease affecting livestock worldwide. Here, using structural and biochemical analyses, we have identified FMDV 3D pol mutations that affect polymerase fidelity. Recombinant FMDVs containing substitutions at 3D pol tryptophan residue 237 were genetically stable and displayed plaque phenotypes and growth kinetics similar to those of the wild-type virus in cell culture. We further demonstrate that viruses harboring either a W237F HF substitution or W237I LF and W237L LF mutations were highly attenuated in animals. Our study shows that obtaining 3D pol fidelity variants by protein engineering based on polymerase structure and function could be exploited for the development of attenuated FMDV vaccine candidates that are safer and more stable than strains obtained by selective pressure via mutagenic nucleotides or adaptation approaches. Copyright © 2017 American Society for Microbiology.

Attenuation of Foot-and-Mouth Disease Virus by Engineered Viral Polymerase Fidelity

PubMed Central

Rai, Devendra K.; Diaz-San Segundo, Fayna; Campagnola, Grace; Keith, Anna; Schafer, Elizabeth A.; Kloc, Anna; de los Santos, Teresa; Peersen, Olve

2017-01-01

ABSTRACT Foot-and-mouth disease virus (FMDV) RNA-dependent RNA polymerase (RdRp) (3Dpol) catalyzes viral RNA synthesis. Its characteristic low fidelity and absence of proofreading activity allow FMDV to rapidly mutate and adapt to dynamic environments. In this study, we used the structure of FMDV 3Dpol in combination with previously reported results from similar picornaviral polymerases to design point mutations that would alter replication fidelity. In particular, we targeted Trp237 within conserved polymerase motif A because of the low reversion potential inherent in the single UGG codon. Using biochemical and genetic tools, we show that the replacement of tryptophan 237 with phenylalanine imparts higher fidelity, but replacements with isoleucine and leucine resulted in lower-fidelity phenotypes. Viruses containing these W237 substitutions show in vitro growth kinetics and plaque morphologies similar to those of the wild-type (WT) A24 Cruzeiro strain in BHK cells, and both high- and low-fidelity variants retained fitness during coinfection with the wild-type virus. The higher-fidelity W237F (W237FHF) mutant virus was more resistant to the mutagenic nucleoside analogs ribavirin and 5-fluorouracil than the WT virus, whereas the lower-fidelity W237I (W237ILF) and W237LLF mutant viruses exhibited lower ribavirin resistance. Interestingly, the variant viruses showed heterogeneous and slightly delayed growth kinetics in primary porcine kidney cells, and they were significantly attenuated in mouse infection experiments. These data demonstrate, for a single virus, that either increased or decreased RdRp fidelity attenuates virus growth in animals, which is a desirable feature for the development of safer and genetically more stable vaccine candidates. IMPORTANCE Foot-and-mouth disease (FMD) is the most devastating disease affecting livestock worldwide. Here, using structural and biochemical analyses, we have identified FMDV 3Dpol mutations that affect polymerase fidelity. Recombinant FMDVs containing substitutions at 3Dpol tryptophan residue 237 were genetically stable and displayed plaque phenotypes and growth kinetics similar to those of the wild-type virus in cell culture. We further demonstrate that viruses harboring either a W237FHF substitution or W237ILF and W237LLF mutations were highly attenuated in animals. Our study shows that obtaining 3Dpol fidelity variants by protein engineering based on polymerase structure and function could be exploited for the development of attenuated FMDV vaccine candidates that are safer and more stable than strains obtained by selective pressure via mutagenic nucleotides or adaptation approaches. PMID:28515297

Coordinating DNA polymerase traffic during high and low fidelity synthesis.

PubMed

Sutton, Mark D

2010-05-01

With the discovery that organisms possess multiple DNA polymerases (Pols) displaying different fidelities, processivities, and activities came the realization that mechanisms must exist to manage the actions of these diverse enzymes to prevent gratuitous mutations. Although many of the Pols encoded by most organisms are largely accurate, and participate in DNA replication and DNA repair, a sizeable fraction display a reduced fidelity, and act to catalyze potentially error-prone translesion DNA synthesis (TLS) past lesions that persist in the DNA. Striking the proper balance between use of these different enzymes during DNA replication, DNA repair, and TLS is essential for ensuring accurate duplication of the cell's genome. This review highlights mechanisms that organisms utilize to manage the actions of their different Pols. A particular emphasis is placed on discussion of current models for how different Pols switch places with each other at the replication fork during high fidelity replication and potentially error-pone TLS. Copyright (c) 2010 Elsevier B.V. All rights reserved.

The Simplified Aircraft-Based Paired Approach With the ALAS Alerting Algorithm

NASA Technical Reports Server (NTRS)

Perry, Raleigh B.; Madden, Michael M.; Torres-Pomales, Wilfredo; Butler, Ricky W.

2013-01-01

This paper presents the results of an investigation of a proposed concept for closely spaced parallel runways called the Simplified Aircraft-based Paired Approach (SAPA). This procedure depends upon a new alerting algorithm called the Adjacent Landing Alerting System (ALAS). This study used both low fidelity and high fidelity simulations to validate the SAPA procedure and test the performance of the new alerting algorithm. The low fidelity simulation enabled a determination of minimum approach distance for the worst case over millions of scenarios. The high fidelity simulation enabled an accurate determination of timings and minimum approach distance in the presence of realistic trajectories, communication latencies, and total system error for 108 test cases. The SAPA procedure and the ALAS alerting algorithm were applied to the 750-ft parallel spacing (e.g., SFO 28L/28R) approach problem. With the SAPA procedure as defined in this paper, this study concludes that a 750-ft application does not appear to be feasible, but preliminary results for 1000-ft parallel runways look promising.

High-Fidelity Tissue Engineering of Patient-Specific Auricles for Reconstruction of Pediatric Microtia and Other Auricular Deformities

PubMed Central

Reiffel, Alyssa J.; Kafka, Concepcion; Hernandez, Karina A.; Popa, Samantha; Perez, Justin L.; Zhou, Sherry; Pramanik, Satadru; Brown, Bryan N.; Ryu, Won Seuk; Bonassar, Lawrence J.; Spector, Jason A.

2013-01-01

Introduction Autologous techniques for the reconstruction of pediatric microtia often result in suboptimal aesthetic outcomes and morbidity at the costal cartilage donor site. We therefore sought to combine digital photogrammetry with CAD/CAM techniques to develop collagen type I hydrogel scaffolds and their respective molds that would precisely mimic the normal anatomy of the patient-specific external ear as well as recapitulate the complex biomechanical properties of native auricular elastic cartilage while avoiding the morbidity of traditional autologous reconstructions. Methods Three-dimensional structures of normal pediatric ears were digitized and converted to virtual solids for mold design. Image-based synthetic reconstructions of these ears were fabricated from collagen type I hydrogels. Half were seeded with bovine auricular chondrocytes. Cellular and acellular constructs were implanted subcutaneously in the dorsa of nude rats and harvested after 1 and 3 months. Results Gross inspection revealed that acellular implants had significantly decreased in size by 1 month. Cellular constructs retained their contour/projection from the animals' dorsa, even after 3 months. Post-harvest weight of cellular constructs was significantly greater than that of acellular constructs after 1 and 3 months. Safranin O-staining revealed that cellular constructs demonstrated evidence of a self-assembled perichondrial layer and copious neocartilage deposition. Verhoeff staining of 1 month cellular constructs revealed de novo elastic cartilage deposition, which was even more extensive and robust after 3 months. The equilibrium modulus and hydraulic permeability of cellular constructs were not significantly different from native bovine auricular cartilage after 3 months. Conclusions We have developed high-fidelity, biocompatible, patient-specific tissue-engineered constructs for auricular reconstruction which largely mimic the native auricle both biomechanically and histologically, even after an extended period of implantation. This strategy holds immense potential for durable patient-specific tissue-engineered anatomically proper auricular reconstructions in the future. PMID:23437148

Pellet-clad mechanical interaction screening using VERA applied to Watts Bar Unit 1, Cycles 1–3

DOE PAGES

Stimpson, Shane; Powers, Jeffrey; Clarno, Kevin; ...

2017-12-22

The Consortium for Advanced Simulation of Light Water Reactors (CASL) aims to provide high-fidelity multiphysics simulations of light water nuclear reactors. To accomplish this, CASL is developing the Virtual Environment for Reactor Applications (VERA), which is a suite of code packages for thermal hydraulics, neutron transport, fuel performance, and coolant chemistry. As VERA continues to grow and expand, there has been an increased focus on incorporating fuel performance analysis methods. One of the primary goals of CASL is to estimate local cladding failure probability through pellet-clad interaction, which consists of both pellet-clad mechanical interaction (PCMI) and stress corrosion cracking. Estimatingmore » clad failure is important to preventing release of fission products to the primary system and accurate estimates could prove useful in establishing less conservative power ramp rates or when considering load-follow operations.While this capability is being pursued through several different approaches, the procedure presented in this article focuses on running independent fuel performance calculations with BISON using a file-based one-way coupling based on multicycle output data from high fidelity, pin-resolved coupled neutron transport–thermal hydraulics simulations. This type of approach is consistent with traditional fuel performance analysis methods, which are typically separate from core simulation analyses. A more tightly coupled approach is currently being developed, which is the ultimate target application in CASL.Recent work simulating 12 cycles of Watts Bar Unit 1 with VERA core simulator are capitalized upon, and quarter-core BISON results for parameters of interest to PCMI (maximum centerline fuel temperature, maximum clad hoop stress, and minimum gap size) are presented for Cycles 1–3. In conclusion, based on these results, this capability demonstrates its value and how it could be used as a screening tool for gathering insight into PCMI, singling out limiting rods for further, more detailed analysis.« less

Pellet-clad mechanical interaction screening using VERA applied to Watts Bar Unit 1, Cycles 1–3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stimpson, Shane; Powers, Jeffrey; Clarno, Kevin

The Consortium for Advanced Simulation of Light Water Reactors (CASL) aims to provide high-fidelity multiphysics simulations of light water nuclear reactors. To accomplish this, CASL is developing the Virtual Environment for Reactor Applications (VERA), which is a suite of code packages for thermal hydraulics, neutron transport, fuel performance, and coolant chemistry. As VERA continues to grow and expand, there has been an increased focus on incorporating fuel performance analysis methods. One of the primary goals of CASL is to estimate local cladding failure probability through pellet-clad interaction, which consists of both pellet-clad mechanical interaction (PCMI) and stress corrosion cracking. Estimatingmore » clad failure is important to preventing release of fission products to the primary system and accurate estimates could prove useful in establishing less conservative power ramp rates or when considering load-follow operations.While this capability is being pursued through several different approaches, the procedure presented in this article focuses on running independent fuel performance calculations with BISON using a file-based one-way coupling based on multicycle output data from high fidelity, pin-resolved coupled neutron transport–thermal hydraulics simulations. This type of approach is consistent with traditional fuel performance analysis methods, which are typically separate from core simulation analyses. A more tightly coupled approach is currently being developed, which is the ultimate target application in CASL.Recent work simulating 12 cycles of Watts Bar Unit 1 with VERA core simulator are capitalized upon, and quarter-core BISON results for parameters of interest to PCMI (maximum centerline fuel temperature, maximum clad hoop stress, and minimum gap size) are presented for Cycles 1–3. In conclusion, based on these results, this capability demonstrates its value and how it could be used as a screening tool for gathering insight into PCMI, singling out limiting rods for further, more detailed analysis.« less

Critical thinking skills in nursing students: comparison of simulation-based performance with metrics.

PubMed

Fero, Laura J; O'Donnell, John M; Zullo, Thomas G; Dabbs, Annette DeVito; Kitutu, Julius; Samosky, Joseph T; Hoffman, Leslie A

2010-10-01

This paper is a report of an examination of the relationship between metrics of critical thinking skills and performance in simulated clinical scenarios. Paper and pencil assessments are commonly used to assess critical thinking but may not reflect simulated performance. In 2007, a convenience sample of 36 nursing students participated in measurement of critical thinking skills and simulation-based performance using videotaped vignettes, high-fidelity human simulation, the California Critical Thinking Disposition Inventory and California Critical Thinking Skills Test. Simulation-based performance was rated as 'meeting' or 'not meeting' overall expectations. Test scores were categorized as strong, average, or weak. Most (75.0%) students did not meet overall performance expectations using videotaped vignettes or high-fidelity human simulation; most difficulty related to problem recognition and reporting findings to the physician. There was no difference between overall performance based on method of assessment (P = 0.277). More students met subcategory expectations for initiating nursing interventions (P ≤ 0.001) using high-fidelity human simulation. The relationship between videotaped vignette performance and critical thinking disposition or skills scores was not statistically significant, except for problem recognition and overall critical thinking skills scores (Cramer's V = 0.444, P = 0.029). There was a statistically significant relationship between overall high-fidelity human simulation performance and overall critical thinking disposition scores (Cramer's V = 0.413, P = 0.047). Students' performance reflected difficulty meeting expectations in simulated clinical scenarios. High-fidelity human simulation performance appeared to approximate scores on metrics of critical thinking best. Further research is needed to determine if simulation-based performance correlates with critical thinking skills in the clinical setting. © 2010 The Authors. Journal of Advanced Nursing © 2010 Blackwell Publishing Ltd.

Critical thinking skills in nursing students: comparison of simulation-based performance with metrics

PubMed Central

Fero, Laura J.; O’Donnell, John M.; Zullo, Thomas G.; Dabbs, Annette DeVito; Kitutu, Julius; Samosky, Joseph T.; Hoffman, Leslie A.

2018-01-01

Aim This paper is a report of an examination of the relationship between metrics of critical thinking skills and performance in simulated clinical scenarios. Background Paper and pencil assessments are commonly used to assess critical thinking but may not reflect simulated performance. Methods In 2007, a convenience sample of 36 nursing students participated in measurement of critical thinking skills and simulation-based performance using videotaped vignettes, high-fidelity human simulation, the California Critical Thinking Disposition Inventory and California Critical Thinking Skills Test. Simulation- based performance was rated as ‘meeting’ or ‘not meeting’ overall expectations. Test scores were categorized as strong, average, or weak. Results Most (75·0%) students did not meet overall performance expectations using videotaped vignettes or high-fidelity human simulation; most difficulty related to problem recognition and reporting findings to the physician. There was no difference between overall performance based on method of assessment (P = 0·277). More students met subcategory expectations for initiating nursing interventions (P ≤ 0·001) using high-fidelity human simulation. The relationship between video-taped vignette performance and critical thinking disposition or skills scores was not statistically significant, except for problem recognition and overall critical thinking skills scores (Cramer’s V = 0·444, P = 0·029). There was a statistically significant relationship between overall high-fidelity human simulation performance and overall critical thinking disposition scores (Cramer’s V = 0·413, P = 0·047). Conclusion Students’ performance reflected difficulty meeting expectations in simulated clinical scenarios. High-fidelity human simulation performance appeared to approximate scores on metrics of critical thinking best. Further research is needed to determine if simulation-based performance correlates with critical thinking skills in the clinical setting. PMID:20636471

Key features for ATA / ATR database design in missile systems

NASA Astrophysics Data System (ADS)

Özertem, Kemal Arda

2017-05-01

Automatic target acquisition (ATA) and automatic target recognition (ATR) are two vital tasks for missile systems, and having a robust detection and recognition algorithm is crucial for overall system performance. In order to have a robust target detection and recognition algorithm, an extensive image database is required. Automatic target recognition algorithms use the database of images in training and testing steps of algorithm. This directly affects the recognition performance, since the training accuracy is driven by the quality of the image database. In addition, the performance of an automatic target detection algorithm can be measured effectively by using an image database. There are two main ways for designing an ATA / ATR database. The first and easy way is by using a scene generator. A scene generator can model the objects by considering its material information, the atmospheric conditions, detector type and the territory. Designing image database by using a scene generator is inexpensive and it allows creating many different scenarios quickly and easily. However the major drawback of using a scene generator is its low fidelity, since the images are created virtually. The second and difficult way is designing it using real-world images. Designing image database with real-world images is a lot more costly and time consuming; however it offers high fidelity, which is critical for missile algorithms. In this paper, critical concepts in ATA / ATR database design with real-world images are discussed. Each concept is discussed in the perspective of ATA and ATR separately. For the implementation stage, some possible solutions and trade-offs for creating the database are proposed, and all proposed approaches are compared to each other with regards to their pros and cons.

Non-US data compression and coding research. FASAC Technical Assessment Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gray, R.M.; Cohn, M.; Craver, L.W.

1993-11-01

This assessment of recent data compression and coding research outside the United States examines fundamental and applied work in the basic areas of signal decomposition, quantization, lossless compression, and error control, as well as application development efforts in image/video compression and speech/audio compression. Seven computer scientists and engineers who are active in development of these technologies in US academia, government, and industry carried out the assessment. Strong industrial and academic research groups in Western Europe, Israel, and the Pacific Rim are active in the worldwide search for compression algorithms that provide good tradeoffs among fidelity, bit rate, and computational complexity,more » though the theoretical roots and virtually all of the classical compression algorithms were developed in the United States. Certain areas, such as segmentation coding, model-based coding, and trellis-coded modulation, have developed earlier or in more depth outside the United States, though the United States has maintained its early lead in most areas of theory and algorithm development. Researchers abroad are active in other currently popular areas, such as quantizer design techniques based on neural networks and signal decompositions based on fractals and wavelets, but, in most cases, either similar research is or has been going on in the United States, or the work has not led to useful improvements in compression performance. Because there is a high degree of international cooperation and interaction in this field, good ideas spread rapidly across borders (both ways) through international conferences, journals, and technical exchanges. Though there have been no fundamental data compression breakthroughs in the past five years--outside or inside the United State--there have been an enormous number of significant improvements in both places in the tradeoffs among fidelity, bit rate, and computational complexity.« less

High-fidelity simulation of transcutaneous cardiac pacing: characteristics and limitations of available high-fidelity simulators, and description of an alternative two-mannequin model.

PubMed

Robitaille, Arnaud; Perron, Roger; Germain, Jean-François; Tanoubi, Issam; Georgescu, Mihai

2015-04-01

Transcutaneous cardiac pacing (TCP) is a potentially lifesaving technique that is part of the recommended treatment for symptomatic bradycardia. Transcutaneous cardiac pacing however is used uncommonly, and its successful application is not straightforward. Simulation could, therefore, play an important role in the teaching and assessment of TCP competence. However, even the highest-fidelity mannequins available on the market have important shortcomings, which limit the potential of simulation. Six criteria defining clinical competency in TCP were established and used as a starting point in the creation of an improved TCP simulator. The goal was a model that could be used to assess experienced clinicians, an objective that justifies the additional effort required by the increased fidelity. The proposed 2-mannequin model (TMM) combines a highly modified Human Patient Simulator with a SimMan 3G, the latter being used solely to provide the electrocardiography (ECG) tracing. The TMM improves the potential of simulation to assess experienced clinicians (1) by reproducing key features of TCP, like using the same multifunctional pacing electrodes used clinically, allowing dual ECG monitoring, and responding with upper body twitching when stimulated, but equally importantly (2) by reproducing key pitfalls of the technique, like allowing pacing electrode misplacement and reproducing false signs of ventricular capture, commonly, but erroneously, used clinically to establish that effective pacing has been achieved (like body twitching, electrical artifact on the ECG, and electrical capture without ventricular capture). The proposed TMM uses a novel combination of 2 high-fidelity mannequins to improve TCP simulation until upgraded mannequins become commercially available.

Simulator technology as a tool for education in cardiac care.

PubMed

Hravnak, Marilyn; Beach, Michael; Tuite, Patricia

2007-01-01

Assisting nurses in gaining the cognitive and psychomotor skills necessary to safely and effectively care for patients with cardiovascular disease can be challenging for educators. Ideally, nurses would have the opportunity to synthesize and practice these skills in a protected training environment before application in the dynamic clinical setting. Recently, a technology known as high fidelity human simulation was introduced, which permits learners to interact with a simulated patient. The dynamic physiologic parameters and physical assessment capabilities of the simulated patient provide for a realistic learning environment. This article describes the High Fidelity Human Simulation Laboratory at the University of Pittsburgh School of Nursing and presents strategies for using this technology as a tool in teaching complex cardiac nursing care at the basic and advanced practice nursing levels. The advantages and disadvantages of high fidelity human simulation in learning are discussed.

Autonomous Aerobraking: Thermal Analysis and Response Surface Development

NASA Technical Reports Server (NTRS)

Dec, John A.; Thornblom, Mark N.

2011-01-01

A high-fidelity thermal model of the Mars Reconnaissance Orbiter was developed for use in an autonomous aerobraking simulation study. Response surface equations were derived from the high-fidelity thermal model and integrated into the autonomous aerobraking simulation software. The high-fidelity thermal model was developed using the Thermal Desktop software and used in all phases of the analysis. The use of Thermal Desktop exclusively, represented a change from previously developed aerobraking thermal analysis methodologies. Comparisons were made between the Thermal Desktop solutions and those developed for the previous aerobraking thermal analyses performed on the Mars Reconnaissance Orbiter during aerobraking operations. A variable sensitivity screening study was performed to reduce the number of variables carried in the response surface equations. Thermal analysis and response surface equation development were performed for autonomous aerobraking missions at Mars and Venus.

Band-selective shaped pulse for high fidelity quantum control in diamond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Yan-Chun; Xing, Jian; Liu, Gang-Qin

High fidelity quantum control of qubits is crucially important for realistic quantum computing, and it becomes more challenging when there are inevitable interactions between qubits. We introduce a band-selective shaped pulse, refocusing BURP (REBURP) pulse, to cope with the problems. The electron spin of nitrogen-vacancy centers in diamond is flipped with high fidelity by the REBURP pulse. In contrast with traditional rectangular pulses, the shaped pulse has almost equal excitation effect in a sharply edged region (in frequency domain). So the three sublevels of host {sup 14}N nuclear spin can be flipped accurately simultaneously, while unwanted excitations of other sublevelsmore » (e.g., of a nearby {sup 13}C nuclear spin) is well suppressed. Our scheme can be used for various applications such as quantum metrology, quantum sensing, and quantum information process.« less

Experimental demonstration of high fidelity entanglement distribution over decoherence channels via qubit transduction.

PubMed

Lim, Hyang-Tag; Hong, Kang-Hee; Kim, Yoon-Ho

2015-10-21

Quantum coherence and entanglement, which are essential resources for quantum information, are often degraded and lost due to decoherence. Here, we report a proof-of-principle experimental demonstration of high fidelity entanglement distribution over decoherence channels via qubit transduction. By unitarily switching the initial qubit encoding to another, which is insensitive to particular forms of decoherence, we have demonstrated that it is possible to avoid the effect of decoherence completely. In particular, we demonstrate high-fidelity distribution of photonic polarization entanglement over quantum channels with two types of decoherence, amplitude damping and polarization-mode dispersion, via qubit transduction between polarization qubits and dual-rail qubits. These results represent a significant breakthrough in quantum communication over decoherence channels as the protocol is input-state independent, requires no ancillary photons and symmetries, and has near-unity success probability.

Experimental demonstration of high fidelity entanglement distribution over decoherence channels via qubit transduction

PubMed Central

Lim, Hyang-Tag; Hong, Kang-Hee; Kim, Yoon-Ho

2015-01-01

Quantum coherence and entanglement, which are essential resources for quantum information, are often degraded and lost due to decoherence. Here, we report a proof-of-principle experimental demonstration of high fidelity entanglement distribution over decoherence channels via qubit transduction. By unitarily switching the initial qubit encoding to another, which is insensitive to particular forms of decoherence, we have demonstrated that it is possible to avoid the effect of decoherence completely. In particular, we demonstrate high-fidelity distribution of photonic polarization entanglement over quantum channels with two types of decoherence, amplitude damping and polarization-mode dispersion, via qubit transduction between polarization qubits and dual-rail qubits. These results represent a significant breakthrough in quantum communication over decoherence channels as the protocol is input-state independent, requires no ancillary photons and symmetries, and has near-unity success probability. PMID:26487083

AVESTAR Center for Operational Excellence of Electricity Generation Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zitney, Stephen

2012-08-29

To address industry challenges in attaining operational excellence for electricity generation plants, the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) has launched a world-class facility for Advanced Virtual Energy Simulation Training and Research (AVESTARTM). This presentation will highlight the AVESTARTM Center simulators, facilities, and comprehensive training, education, and research programs focused on the operation and control of high-efficiency, near-zero-emission electricity generation plants. The AVESTAR Center brings together state-of-the-art, real-time, high-fidelity dynamic simulators with full-scope operator training systems (OTSs) and 3D virtual immersive training systems (ITSs) into an integrated energy plant and control room environment. AVESTAR’s initial offeringmore » combines--for the first time--a “gasification with CO2 capture” process simulator with a “combined-cycle” power simulator together in a single OTS/ITS solution for an integrated gasification combined cycle (IGCC) power plant with carbon dioxide (CO2) capture. IGCC systems are an attractive technology option for power generation, especially when capturing and storing CO2 is necessary to satisfy emission targets. The AVESTAR training program offers a variety of courses that merge classroom learning, simulator-based OTS learning in a control-room operations environment, and immersive learning in the interactive 3D virtual plant environment or ITS. All of the courses introduce trainees to base-load plant operation, control, startups, and shutdowns. Advanced courses require participants to become familiar with coordinated control, fuel switching, power-demand load shedding, and load following, as well as to problem solve equipment and process malfunctions. Designed to ensure work force development, training is offered for control room and plant field operators, as well as engineers and managers. Such comprehensive simulator-based instruction allows for realistic training without compromising worker, equipment, and environmental safety. It also better prepares operators and engineers to manage the plant closer to economic constraints while minimizing or avoiding the impact of any potentially harmful, wasteful, or inefficient events. The AVESTAR Center is also used to augment graduate and undergraduate engineering education in the areas of process simulation, dynamics, control, and safety. Students and researchers gain hands-on simulator-based training experience and learn how the commercial-scale power plants respond dynamically to changes in manipulated inputs, such as coal feed flow rate and power demand. Students also analyze how the regulatory control system impacts power plant performance and stability. In addition, students practice start-up, shutdown, and malfunction scenarios. The 3D virtual ITSs are used for plant familiarization, walk-through, equipment animations, and safety scenarios. To further leverage the AVESTAR facilities and simulators, NETL and its university partners are pursuing an innovative and collaborative R&D program. In the area of process control, AVESTAR researchers are developing enhanced strategies for regulatory control and coordinated plant-wide control, including gasifier and gas turbine lead, as well as advanced process control using model predictive control (MPC) techniques. Other AVESTAR R&D focus areas include high-fidelity equipment modeling using partial differential equations, dynamic reduced order modeling, optimal sensor placement, 3D virtual plant simulation, and modern grid. NETL and its partners plan to continue building the AVESTAR portfolio of dynamic simulators, immersive training systems, and advanced research capabilities to satisfy industry’s growing need for training and experience with the operation and control of clean energy plants. Future dynamic simulators under development include natural gas combined cycle (NGCC) and supercritical pulverized coal (SCPC) plants with post-combustion CO2 capture. These dynamic simulators are targeted for use in establishing a Virtual Carbon Capture Center (VCCC), similar in concept to the DOE’s National Carbon Capture Center for slipstream testing. The VCCC will enable developers of CO2 capture technologies to integrate, test, and optimize the operation of their dynamic capture models within the context of baseline power plant dynamic models. The objective is to provide hands-on, simulator-based “learn-by-operating” test platforms to accelerate the scale-up and deployment of CO2 capture technologies. Future AVESTAR plans also include pursuing R&D on the dynamics, operation, and control of integrated electricity generation and storage systems for the modern grid era. Special emphasis will be given to combining load-following energy plants with renewable and distributed generating supplies and fast-ramping energy storage systems to provide near constant baseload power.« less

Towards the Integration of APECS with VE-Suite to Create a Comprehensive Virtual Engineering Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCorkle, D.; Yang, C.; Jordan, T.

2007-06-01

Modeling and simulation tools are becoming pervasive in the process engineering practice of designing advanced power generation facilities. These tools enable engineers to explore many what-if scenarios before cutting metal or constructing a pilot scale facility. While such tools enable investigation of crucial plant design aspects, typical commercial process simulation tools such as Aspen Plus®, gPROMS®, and HYSYS® still do not explore some plant design information, including computational fluid dynamics (CFD) models for complex thermal and fluid flow phenomena, economics models for policy decisions, operational data after the plant is constructed, and as-built information for use in as-designed models. Softwaremore » tools must be created that allow disparate sources of information to be integrated if environments are to be constructed where process simulation information can be accessed. At the Department of Energy’s (DOE) National Energy Technology Laboratory (NETL), the Advanced Process Engineering Co-Simulator (APECS) has been developed as an integrated software suite that combines process simulation (e.g., Aspen Plus) and high-fidelity equipment simulation (e.g., Fluent® CFD), together with advanced analysis capabilities including case studies, sensitivity analysis, stochastic simulation for risk/uncertainty analysis, and multi-objective optimization. In this paper, we discuss the initial phases of integrating APECS with the immersive and interactive virtual engineering software, VE-Suite, developed at Iowa State University and Ames Laboratory. VE-Suite utilizes the ActiveX (OLE Automation) controls in Aspen Plus wrapped by the CASI library developed by Reaction Engineering International to run the process simulation and query for unit operation results. This integration permits any application that uses the VE-Open interface to integrate with APECS co-simulations, enabling construction of the comprehensive virtual engineering environment needed for the rapid engineering of advanced power generation facilities.« less

A pilot test of the GoWoman weight management intervention for women with mobility impairments in the online virtual world of Second Life®.

PubMed

Nosek, Margaret A; Robinson-Whelen, Susan; Ledoux, Tracey A; Hughes, Rosemary B; O'Connor, Daniel P; Lee, Rebecca E; Goe, Rebecca; Silveira, Stephanie L; Markley, Rachel; Nosek, Thomas M

2018-06-11

Pilot test GoWoman, a small-group weight management intervention for mobility impaired women that was a disability- and gender-responsive adaptation of the Diabetes Prevention Program delivered in the online virtual world of Second Life ® . Objectives were to (1) examine pre-/post-intervention differences in weight, waist circumference, diet, physical activity, self-efficacy for diet and physical activity, nutrition knowledge and social support for weight management, (2) determine intervention feasibility (fidelity, attrition, engagement, acceptability). Single-group modified interrupted time series quasi-experimental design whereby participants served as their own controls. Thirteen women attended ≥8 of 16 GoWoman weekly sessions and lost an average of 5.97 pounds (2.71 kg) (3.31%) body weight (Cohen's d = 0.74) and 1.44 inches (3.66 cm) (3.58%) waist circumference (Cohen's d = 0.83). There were significant improvements in physical activity, diet and self-efficacy for diet and physical activity. All benchmarks for feasibility were met. Ratings of intervention content, group interactions and support and virtual world experiences were highly positive. Findings suggest that a disability- and gender-responsive weight management intervention with peer group support delivered in an online virtual world is feasible, meaningful and may assist with weight management for mobility impaired women. Implications for Rehabilitation This study addresses a gap in the general and rehabilitation research literature by addressing the disproportionately high rates of obesity among women with mobility impairments, who are generally excluded from tests of weight management interventions if they have limited ability to engage in vigorous physical activity. The GoWoman program is an adaptation of the Diabetes Prevention Program Lifestyle Change curriculum that is tailored to meet the unique weight management needs of women with mobility impairments, and was created to become a publicly available, disability- and gender-responsive intervention that can be used in community and rehabilitation settings. More rehabilitation and health promotion program should be offered in the free, online, virtual world of Second Life ® since participants in this pilot study offered many favorable comments about the new learning and social opportunities available to them there and they did not have to deal with the disability-related environmental and health challenges that often prevent them from participating in face-to-face workshops. Preliminary indications of improvements in body weight, waist circumference, diet and physical activity after attending the GoWoman weight management intervention offered in Second Life ® tell us that these strategies are feasible for helping women with mobility impairments manage their weight and should undergo further testing.

SOWFA Super-Controller: A High-Fidelity Tool for Evaluating Wind Plant Control Approaches

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fleming, P.; Gebraad, P.; van Wingerden, J. W.

2013-01-01

This paper presents a new tool for testing wind plant controllers in the Simulator for Offshore Wind Farm Applications (SOWFA). SOWFA is a high-fidelity simulator for the interaction between wind turbine dynamics and the fluid flow in a wind plant. The new super-controller testing environment in SOWFA allows for the implementation of the majority of the wind plant control strategies proposed in the literature.

Simulation Learning: PC-Screen Based (PCSB) versus High Fidelity Simulation (HFS)

DTIC Science & Technology

2012-08-01

methods for the use of simulation for teaching clinical skills to military and civilian clinicians . High fidelity simulation is an expensive method of...without the knowledge and approval of the IRB. Changes include, but not limited to, modifications in study design, recruitment process and number of...Person C-Collar simulation algorithm Pathway A Scenario A - Spinal stabilization: Sub processes Legend: Pathway Points Complex task to be performed by

Compact Single Site Resolution Cold Atom Experiment for Adiabatic Quantum Computing

DTIC Science & Technology

2016-02-03

goal of our scientific investigation is to demonstrate high fidelity and fast atom-atom entanglement between physically 1. REPORT DATE (DD-MM-YYYY) 4...of our scientific investigation is to demonstrate high fidelity and fast atom-atom entanglement between physically separated and optically addressed...Specifically, we will design and construct a set of compact single atom traps with integrated optics, suitable for heralded entanglement and loophole

High-fidelity patient simulation in nursing education: an integrative review.

PubMed

Weaver, Amy

2011-01-01

An integrative review was undertaken to analyze studies published since 1998 on the use of high-fidelity patient simulation (HFPS) in undergraduate nursing education. This review found that HFPS benefits nursing students in terms of knowledge, value, realism, and learner satisfaction;findings were mixed in the areas of student confidence, knowledge transfer, and stress. Further research in these and other areas will determine whether its increased use is warranted.

Rapidly reconfigurable high-fidelity optical arbitrary waveform generation in heterogeneous photonic integrated circuits.

PubMed

Feng, Shaoqi; Qin, Chuan; Shang, Kuanping; Pathak, Shibnath; Lai, Weicheng; Guan, Binbin; Clements, Matthew; Su, Tiehui; Liu, Guangyao; Lu, Hongbo; Scott, Ryan P; Ben Yoo, S J

2017-04-17

This paper demonstrates rapidly reconfigurable, high-fidelity optical arbitrary waveform generation (OAWG) in a heterogeneous photonic integrated circuit (PIC). The heterogeneous PIC combines advantages of high-speed indium phosphide (InP) modulators and low-loss, high-contrast silicon nitride (Si₃N₄) arrayed waveguide gratings (AWGs) so that high-fidelity optical waveform syntheses with rapid waveform updates are possible. The generated optical waveforms spanned a 160 GHz spectral bandwidth starting from an optical frequency comb consisting of eight comb lines separated by 20 GHz channel spacing. The Error Vector Magnitude (EVM) values of the generated waveforms were approximately 16.4%. The OAWG module can rapidly and arbitrarily reconfigure waveforms upon every pulse arriving at 2 ns repetition time. The result of this work indicates the feasibility of truly dynamic optical arbitrary waveform generation where the reconfiguration rate or the modulator bandwidth must exceed the channel spacing of the AWG and the optical frequency comb.

High-fidelity spin entanglement using optimal control.

PubMed

Dolde, Florian; Bergholm, Ville; Wang, Ya; Jakobi, Ingmar; Naydenov, Boris; Pezzagna, Sébastien; Meijer, Jan; Jelezko, Fedor; Neumann, Philipp; Schulte-Herbrüggen, Thomas; Biamonte, Jacob; Wrachtrup, Jörg

2014-02-28

Precise control of quantum systems is of fundamental importance in quantum information processing, quantum metrology and high-resolution spectroscopy. When scaling up quantum registers, several challenges arise: individual addressing of qubits while suppressing cross-talk, entangling distant nodes and decoupling unwanted interactions. Here we experimentally demonstrate optimal control of a prototype spin qubit system consisting of two proximal nitrogen-vacancy centres in diamond. Using engineered microwave pulses, we demonstrate single electron spin operations with a fidelity F≈0.99. With additional dynamical decoupling techniques, we further realize high-quality, on-demand entangled states between two electron spins with F>0.82, mostly limited by the coherence time and imperfect initialization. Crosstalk in a crowded spectrum and unwanted dipolar couplings are simultaneously eliminated to a high extent. Finally, by high-fidelity entanglement swapping to nuclear spin quantum memory, we demonstrate nuclear spin entanglement over a length scale of 25 nm. This experiment underlines the importance of optimal control for scalable room temperature spin-based quantum information devices.

Validation of a Low-Thrust Mission Design Tool Using Operational Navigation Software

NASA Technical Reports Server (NTRS)

Englander, Jacob A.; Knittel, Jeremy M.; Williams, Ken; Stanbridge, Dale; Ellison, Donald H.

2017-01-01

Design of flight trajectories for missions employing solar electric propulsion requires a suitably high-fidelity design tool. In this work, the Evolutionary Mission Trajectory Generator (EMTG) is presented as a medium-high fidelity design tool that is suitable for mission proposals. EMTG is validated against the high-heritage deep-space navigation tool MIRAGE, demonstrating both the accuracy of EMTG's model and an operational mission design and navigation procedure using both tools. The validation is performed using a benchmark mission to the Jupiter Trojans.

Intervention Fidelity in Family-Based Prevention Counseling for Adolescent Problem Behaviors

ERIC Educational Resources Information Center

Hogue, Aaron; Liddle, Howard A.; Singer, Alisa; Leckrone, Jodi

2005-01-01

This study examined fidelity in multidimensional family prevention (MDFP), a family-based prevention counseling model for adolescents at high risk for substance abuse and related behavior problems, in comparison to two empirically based treatments for adolescent drug abuse: multidimensional family therapy (MDFT) and cognitive-behavioral therapy…

Progress towards a microwave-based high-fidelity Toffoli gate with superconducting qubits

NASA Astrophysics Data System (ADS)

Rigetti, Chad; Chow, Jerry; Corcoles, Antonio; Rozen, Jim; Keefe, George; Rothwell, Mary Beth; Rohrs, Jack; Borstelmann, Mark; Divincenzo, David; Ketchen, Mark; Steffen, Matthias

2011-03-01

We describe recent progress at IBM towards a microwave-based implementation of the Toffoli gate using three capacitively shunted flux qubits dispersively coupled to a resonator. We discuss the device architecture and the microwave protocol, along with expected limits to gate fidelity and scaling.

Effect of improving the realism of simulated clinical judgement tasks on nurses' overconfidence and underconfidence: evidence from a comparative confidence calibration analysis.

PubMed

Yang, Huiqin; Thompson, Carl; Bland, Martin

2012-12-01

Apparent overconfidence and underconfidence in clinicians making clinical judgements could be a feature of evaluative research designs that fail to accurately represent clinical environments. To test the effect of improved realism of clinical judgement tasks on confidence calibration performance of nurses and student nurses. A comparative confidence calibration analysis. The study was conducted in a large university of Northern England. Ninety-seven participants rated their confidence - using a scale that ranged from 0 (no confidence) to 100 (totally confident) on dichotomous clinical judgements of critical event risk. The judgements were in response to 25 paper-based and 25 higher fidelity scenarios using a computerised patient simulator and clinical equipment. Scenarios, and judgement criteria of 'correctness', were generated from real patient cases. Using a series of calibration measures (calibration, resolution and over/underconfidence), participants' confidence was calibrated against the proportion of correct judgements. The calibration measures generated by the paper-based and high fidelity clinical simulation conditions were compared. Participants made significantly less accurate clinical judgements of risk in the high fidelity clinical simulations compared to the paper simulations (P=0.0002). They were significantly less confident in high fidelity clinical simulations than paper simulations (P=0.03). However, there was no significant difference of over/underconfidence for participants between the two simulated settings (P=0.06). Participants were no better calibrated in the high fidelity clinical simulations than paper simulations, P=0.85. Likewise, participants had no better ability of discriminating correct judgements from incorrect judgements as measured by the resolution statistic in high fidelity clinical simulations than paper simulations, P=0.76. Improving the realism of simulated judgement tasks led to reduced confidence and judgement accuracy in participants but did not alter confidence calibration. These findings suggest that judgemental miscalibration of confidence in nurses may be a systematic cognitive bias and that simply making scenarios more realistic may not be a sufficient condition for correction. Copyright © 2012 Elsevier Ltd. All rights reserved.

A simple, rapid, high-fidelity and cost-effective PCR-based two-step DNA synthesis method for long gene sequences.

PubMed

Xiong, Ai-Sheng; Yao, Quan-Hong; Peng, Ri-He; Li, Xian; Fan, Hui-Qin; Cheng, Zong-Ming; Li, Yi

2004-07-07

Chemical synthesis of DNA sequences provides a powerful tool for modifying genes and for studying gene function, structure and expression. Here, we report a simple, high-fidelity and cost-effective PCR-based two-step DNA synthesis (PTDS) method for synthesis of long segments of DNA. The method involves two steps. (i) Synthesis of individual fragments of the DNA of interest: ten to twelve 60mer oligonucleotides with 20 bp overlap are mixed and a PCR reaction is carried out with high-fidelity DNA polymerase Pfu to produce DNA fragments that are approximately 500 bp in length. (ii) Synthesis of the entire sequence of the DNA of interest: five to ten PCR products from the first step are combined and used as the template for a second PCR reaction using high-fidelity DNA polymerase pyrobest, with the two outermost oligonucleotides as primers. Compared with the previously published methods, the PTDS method is rapid (5-7 days) and suitable for synthesizing long segments of DNA (5-6 kb) with high G + C contents, repetitive sequences or complex secondary structures. Thus, the PTDS method provides an alternative tool for synthesizing and assembling long genes with complex structures. Using the newly developed PTDS method, we have successfully obtained several genes of interest with sizes ranging from 1.0 to 5.4 kb.

Numerical study of phase conjugation in stimulated Brillouin scattering from an optical waveguide

NASA Astrophysics Data System (ADS)

Lehmberg, R. H.

1983-05-01

Stimulated Brillouin scattering (SBS) in a multimode optical waveguide is examined, and the parameters that affect the wavefront conjugation fidelity are studied. The nonlinear propagation code is briefly described and the calculated quantities are defined. The parameter study in the low reflectivity limit is described, and the effects of pump depletion are considered. The waveguide produced significantly higher fidelities than the focused configuration, in agreement with several experimental studies. The light scattered back through the phase aberrator exhibited a farfield intenstiy profile closely matching that of the incident beam; however, the nearfield intensity exhibited large and rapid spatial inhomogeneities across the entire aberrator, even for conjugation fidelities as high as 98 percent. In the absence of pump depletion, the fidelity increased with average pump intensity for amplitude gains up to around e to the 10th and then decreased slowly and monotonically with higher intensity. For all cases, pump depletion significantly enhanced the fidelity of the wavefront conjugation by inhibiting the small-scale pulling effect.

Short-term prey field lability constrains individual specialisation in resource selection and foraging site fidelity in a marine predator.

PubMed

Courbin, Nicolas; Besnard, Aurélien; Péron, Clara; Saraux, Claire; Fort, Jérôme; Perret, Samuel; Tornos, Jérémy; Grémillet, David

2018-04-16

Spatio-temporally stable prey distributions coupled with individual foraging site fidelity are predicted to favour individual resource specialisation. Conversely, predators coping with dynamic prey distributions should diversify their individual diet and/or shift foraging areas to increase net intake. We studied individual specialisation in Scopoli's shearwaters (Calonectris diomedea) from the highly dynamic Western Mediterranean, using daily prey distributions together with resource selection, site fidelity and trophic-level analyses. As hypothesised, we found dietary diversification, low foraging site fidelity and almost no individual specialisation in resource selection. Crucially, shearwaters switched daily foraging tactics, selecting areas with contrasting prey of varying trophic levels. Overall, information use and plastic resource selection of individuals with reduced short-term foraging site fidelity allow predators to overcome prey field lability. Our study is an essential step towards a better understanding of individual responses to enhanced environmental stochasticity driven by global changes, and of pathways favouring population persistence. © 2018 John Wiley & Sons Ltd/CNRS.

Design of high-fidelity haptic display for one-dimensional force reflection applications

NASA Astrophysics Data System (ADS)

Gillespie, Brent; Rosenberg, Louis B.

1995-12-01

This paper discusses the development of a virtual reality platform for the simulation of medical procedures which involve needle insertion into human tissue. The paper's focus is the hardware and software requirements for haptic display of a particular medical procedure known as epidural analgesia. To perform this delicate manual procedure, an anesthesiologist must carefully guide a needle through various layers of tissue using only haptic cues for guidance. As a simplifying aspect for the simulator design, all motions and forces involved in the task occur along a fixed line once insertion begins. To create a haptic representation of this procedure, we have explored both physical modeling and perceptual modeling techniques. A preliminary physical model was built based on CT-scan data of the operative site. A preliminary perceptual model was built based on current training techniques for the procedure provided by a skilled instructor. We compare and contrast these two modeling methods and discuss the implications of each. We select and defend the perceptual model as a superior approach for the epidural analgesia simulator.

Weaker axially dipolar time-averaged paleomagnetic field based on multidomain-corrected paleointensities from Galapagos lavas.

PubMed

Wang, Huapei; Kent, Dennis V; Rochette, Pierre

2015-12-08

The geomagnetic field is predominantly dipolar today, and high-fidelity paleomagnetic mean directions from all over the globe strongly support the geocentric axial dipole (GAD) hypothesis for the past few million years. However, the bulk of paleointensity data fails to coincide with the axial dipole prediction of a factor-of-2 equator-to-pole increase in mean field strength, leaving the core dynamo process an enigma. Here, we obtain a multidomain-corrected Pliocene-Pleistocene average paleointensity of 21.6 ± 11.0 µT recorded by 27 lava flows from the Galapagos Archipelago near the Equator. Our new result in conjunction with a published comprehensive study of single-domain-behaved paleointensities from Antarctica (33.4 ± 13.9 µT) that also correspond to GAD directions suggests that the overall average paleomagnetic field over the past few million years has indeed been dominantly dipolar in intensity yet only ∼ 60% of the present-day field strength, with a long-term average virtual axial dipole magnetic moment of the Earth of only 4.9 ± 2.4 × 10(22) A ⋅ m(2).

Simulation in surgery: a review.

PubMed

Tan, Shaun Shi Yan; Sarker, Sudip K

2011-05-01

The ability to acquire surgical skills requires consistent practice, and evidence suggests that many of these technical skills can be learnt away from the operating theatre. The aim of this review article is to discuss the importance of surgical simulation today and its various types, exploring the effectiveness of simulation in the clinical setting and its challenges for the future. Surgical simulation offers the opportunity for trainees to practise their surgical skills prior to entering the operating theatre, allowing detailed feedback and objective assessment of their performance. This enables better patient safety and standards of care. Surgical simulators can be divided into organic or inorganic simulators. Organic simulators, consisting of live animal and fresh human cadaver models, are considered to be of high-fidelity. Inorganic simulators comprise virtual reality simulators and synthetic bench models. Current evidence suggests that skills acquired through training with simulators, positively transfers to the clinical setting and improves operative outcome. The major challenge for the future revolves around understanding the value of this new technology and developing an educational curriculum that can incorporate surgical simulators.

Wake Vortex Advisory System (WakeVAS) Evaluation of Impacts on the National Airspace System

NASA Technical Reports Server (NTRS)

Smith, Jeremy C.; Dollyhigh, Samuel M.

2005-01-01

This report is one of a series that describes an ongoing effort in high-fidelity modeling/simulation, evaluation and analysis of the benefits and performance metrics of the Wake Vortex Advisory System (WakeVAS) Concept of Operations being developed as part of the Virtual Airspace Modeling and Simulation (VAMS) project. A previous study, determined the overall increases in runway arrival rates that could be achieved at 12 selected airports due to WakeVAS reduced aircraft spacing under Instrument Meteorological Conditions. This study builds on the previous work to evaluate the NAS wide impacts of equipping various numbers of airports with WakeVAS. A queuing network model of the National Airspace System, built by the Logistics Management Institute, Mclean, VA, for NASA (LMINET) was used to estimate the reduction in delay that could be achieved by using WakeVAS under non-visual meteorological conditions for the projected air traffic demand in 2010. The results from LMINET were used to estimate the total annual delay reduction that could be achieved and from this, an estimate of the air carrier variable operating cost saving was made.

First of all: Do not harm! Use of simulation for the training of regional anaesthesia techniques: Which skills can be trained without the patient as substitute for a mannequin.

PubMed

Sujatta, Susanne

2015-03-01

Character of clinical skills training is always influenced by technical improvement and cultural changes. Over the last years, two trends have changed the way of traditional apprenticeship-style training in regional anaesthesia: firstly, the development in ultrasound-guided regional anaesthesia, and secondly, the reduced acceptance of using patients as mannequins for invasive techniques. Against this background, simulation techniques are explored, ranging from simple low-fidelity part-task training models to train skills in needle application, to highly sophisticated virtual reality models – the full range is covered. This review tries to discuss all available options with benefits and neglects. The task in clinical practice will be in choosing the right level of sophistication for the desired approach and trainee level. However, the transfer of simulated skills to clinical practice has not been evaluated. It has to be proven whether simulation-trained skills could, as a last consequence, reduce the risk to patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

Weaker axially dipolar time-averaged paleomagnetic field based on multidomain-corrected paleointensities from Galapagos lavas

PubMed Central

Wang, Huapei; Kent, Dennis V.; Rochette, Pierre

2015-01-01

The geomagnetic field is predominantly dipolar today, and high-fidelity paleomagnetic mean directions from all over the globe strongly support the geocentric axial dipole (GAD) hypothesis for the past few million years. However, the bulk of paleointensity data fails to coincide with the axial dipole prediction of a factor-of-2 equator-to-pole increase in mean field strength, leaving the core dynamo process an enigma. Here, we obtain a multidomain-corrected Pliocene–Pleistocene average paleointensity of 21.6 ± 11.0 µT recorded by 27 lava flows from the Galapagos Archipelago near the Equator. Our new result in conjunction with a published comprehensive study of single-domain–behaved paleointensities from Antarctica (33.4 ± 13.9 µT) that also correspond to GAD directions suggests that the overall average paleomagnetic field over the past few million years has indeed been dominantly dipolar in intensity yet only ∼60% of the present-day field strength, with a long-term average virtual axial dipole magnetic moment of the Earth of only 4.9 ± 2.4 × 1022 A⋅m2. PMID:26598664

Predictive optimal control of sewer networks using CORAL tool: application to Riera Blanca catchment in Barcelona.

PubMed

Puig, V; Cembrano, G; Romera, J; Quevedo, J; Aznar, B; Ramón, G; Cabot, J

2009-01-01

This paper deals with the global control of the Riera Blanca catchment in the Barcelona sewer network using a predictive optimal control approach. This catchment has been modelled using a conceptual modelling approach based on decomposing the catchments in subcatchments and representing them as virtual tanks. This conceptual modelling approach allows real-time model calibration and control of the sewer network. The global control problem of the Riera Blanca catchment is solved using a optimal/predictive control algorithm. To implement the predictive optimal control of the Riera Blanca catchment, a software tool named CORAL is used. The on-line control is simulated by interfacing CORAL with a high fidelity simulator of sewer networks (MOUSE). CORAL interchanges readings from the limnimeters and gate commands with MOUSE as if it was connected with the real SCADA system. Finally, the global control results obtained using the predictive optimal control are presented and compared against the results obtained using current local control system. The results obtained using the global control are very satisfactory compared to those obtained using the local control.

High-Fidelity Single-Shot Readout for a Spin Qubit via an Enhanced Latching Mechanism

NASA Astrophysics Data System (ADS)

Harvey-Collard, Patrick; D'Anjou, Benjamin; Rudolph, Martin; Jacobson, N. Tobias; Dominguez, Jason; Ten Eyck, Gregory A.; Wendt, Joel R.; Pluym, Tammy; Lilly, Michael P.; Coish, William A.; Pioro-Ladrière, Michel; Carroll, Malcolm S.

2018-04-01

The readout of semiconductor spin qubits based on spin blockade is fast but suffers from a small charge signal. Previous work suggested large benefits from additional charge mapping processes; however, uncertainties remain about the underlying mechanisms and achievable fidelity. In this work, we study the single-shot fidelity and limiting mechanisms for two variations of an enhanced latching readout. We achieve average single-shot readout fidelities greater than 99.3% and 99.86% for the conventional and enhanced readout, respectively, the latter being the highest to date for spin blockade. The signal amplitude is enhanced to a full one-electron signal while preserving the readout speed. Furthermore, layout constraints are relaxed because the charge sensor signal is no longer dependent on being aligned with the conventional (2,0)-(1,1) charge dipole. Silicon donor-quantum-dot qubits are used for this study, for which the dipole insensitivity substantially relaxes donor placement requirements. One of the readout variations also benefits from a parametric lifetime enhancement by replacing the spin-relaxation process with a charge-metastable one. This provides opportunities to further increase the fidelity. The relaxation mechanisms in the different regimes are investigated. This work demonstrates a readout that is fast, has a one-electron signal, and results in higher fidelity. It further predicts that going beyond 99.9% fidelity in a few microseconds of measurement time is within reach.

Advances in High-Fidelity Multi-Physics Simulation Techniques

DTIC Science & Technology

2008-01-01

predictor - corrector method is used to advance the solution in time. 33 x (m) y (m ) 0 1 2 3.00001 0 1 2 3 4 5 40 x 50 Grid 3 Figure 17: Typical...Unclassified c . THIS PAGE Unclassified 17. LIMITATION OF ABSTRACT: SAR 18. NUMBER OF PAGES 60 Datta Gaitonde 19b. TELEPHONE...advanced parallel computing platforms. The motivation to develop high-fidelity algorithms derives from considerations in various areas of current

ARC integration into the NEAMS Workbench

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stauff, N.; Gaughan, N.; Kim, T.

2017-01-01

One of the objectives of the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Integration Product Line (IPL) is to facilitate the deployment of the high-fidelity codes developed within the program. The Workbench initiative was launched in FY-2017 by the IPL to facilitate the transition from conventional tools to high fidelity tools. The Workbench provides a common user interface for model creation, real-time validation, execution, output processing, and visualization for integrated codes.

High-Fidelity Simulation for Advanced Cardiac Life Support Training

PubMed Central

Davis, Lindsay E.; Storjohann, Tara D.; Spiegel, Jacqueline J.; Beiber, Kellie M.

2013-01-01

Objective. To determine whether a high-fidelity simulation technique compared with lecture would produce greater improvement in advanced cardiac life support (ACLS) knowledge, confidence, and overall satisfaction with the training method. Design. This sequential, parallel-group, crossover trial randomized students into 2 groups distinguished by the sequence of teaching technique delivered for ACLS instruction (ie, classroom lecture vs high-fidelity simulation exercise). Assessment. Test scores on a written examination administered at baseline and after each teaching technique improved significantly from baseline in all groups but were highest when lecture was followed by simulation. Simulation was associated with a greater degree of overall student satisfaction compared with lecture. Participation in a simulation exercise did not improve pharmacy students’ knowledge of ACLS more than attending a lecture, but it was associated with improved student confidence in skills and satisfaction with learning and application. Conclusions. College curricula should incorporate simulation to complement but not replace lecture for ACLS education. PMID:23610477

Implementing a strand of a scalable fault-tolerant quantum computing fabric.

PubMed

Chow, Jerry M; Gambetta, Jay M; Magesan, Easwar; Abraham, David W; Cross, Andrew W; Johnson, B R; Masluk, Nicholas A; Ryan, Colm A; Smolin, John A; Srinivasan, Srikanth J; Steffen, M

2014-06-24

With favourable error thresholds and requiring only nearest-neighbour interactions on a lattice, the surface code is an error-correcting code that has garnered considerable attention. At the heart of this code is the ability to perform a low-weight parity measurement of local code qubits. Here we demonstrate high-fidelity parity detection of two code qubits via measurement of a third syndrome qubit. With high-fidelity gates, we generate entanglement distributed across three superconducting qubits in a lattice where each code qubit is coupled to two bus resonators. Via high-fidelity measurement of the syndrome qubit, we deterministically entangle the code qubits in either an even or odd parity Bell state, conditioned on the syndrome qubit state. Finally, to fully characterize this parity readout, we develop a measurement tomography protocol. The lattice presented naturally extends to larger networks of qubits, outlining a path towards fault-tolerant quantum computing.

General solution to inhomogeneous dephasing and smooth pulse dynamical decoupling

NASA Astrophysics Data System (ADS)

Zeng, Junkai; Deng, Xiu-Hao; Russo, Antonio; Barnes, Edwin

2018-03-01

In order to achieve the high-fidelity quantum control needed for a broad range of quantum information technologies, reducing the effects of noise and system inhomogeneities is an essential task. It is well known that a system can be decoupled from noise or made insensitive to inhomogeneous dephasing dynamically by using carefully designed pulse sequences based on square or delta-function waveforms such as Hahn spin echo or CPMG. However, such ideal pulses are often challenging to implement experimentally with high fidelity. Here, we uncover a new geometrical framework for visualizing all possible driving fields, which enables one to generate an unlimited number of smooth, experimentally feasible pulses that perform dynamical decoupling or dynamically corrected gates to arbitrarily high order. We demonstrate that this scheme can significantly enhance the fidelity of single-qubit operations in the presence of noise and when realistic limitations on pulse rise times and amplitudes are taken into account.

High-fidelity simulation for advanced cardiac life support training.

PubMed

Davis, Lindsay E; Storjohann, Tara D; Spiegel, Jacqueline J; Beiber, Kellie M; Barletta, Jeffrey F

2013-04-12

OBJECTIVE. To determine whether a high-fidelity simulation technique compared with lecture would produce greater improvement in advanced cardiac life support (ACLS) knowledge, confidence, and overall satisfaction with the training method. DESIGN. This sequential, parallel-group, crossover trial randomized students into 2 groups distinguished by the sequence of teaching technique delivered for ACLS instruction (ie, classroom lecture vs high-fidelity simulation exercise). ASSESSMENT. Test scores on a written examination administered at baseline and after each teaching technique improved significantly from baseline in all groups but were highest when lecture was followed by simulation. Simulation was associated with a greater degree of overall student satisfaction compared with lecture. Participation in a simulation exercise did not improve pharmacy students' knowledge of ACLS more than attending a lecture, but it was associated with improved student confidence in skills and satisfaction with learning and application. CONCLUSIONS. College curricula should incorporate simulation to complement but not replace lecture for ACLS education.

Terascale High-Fidelity Simulations of Turbulent Combustion with Detailed Chemistry: Spray Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rutland, Christopher J.

2009-04-26

The Terascale High-Fidelity Simulations of Turbulent Combustion (TSTC) project is a multi-university collaborative effort to develop a high-fidelity turbulent reacting flow simulation capability utilizing terascale, massively parallel computer technology. The main paradigm of the approach is direct numerical simulation (DNS) featuring the highest temporal and spatial accuracy, allowing quantitative observations of the fine-scale physics found in turbulent reacting flows as well as providing a useful tool for development of sub-models needed in device-level simulations. Under this component of the TSTC program the simulation code named S3D, developed and shared with coworkers at Sandia National Laboratories, has been enhanced with newmore » numerical algorithms and physical models to provide predictive capabilities for turbulent liquid fuel spray dynamics. Major accomplishments include improved fundamental understanding of mixing and auto-ignition in multi-phase turbulent reactant mixtures and turbulent fuel injection spray jets.« less

Self-Reflection of Video-Recorded High-Fidelity Simulations and Development of Clinical Judgment.

PubMed

Bussard, Michelle E

2016-09-01

Nurse educators are increasingly using high-fidelity simulators to improve prelicensure nursing students' ability to develop clinical judgment. Traditionally, oral debriefing sessions have immediately followed the simulation scenarios as a method for students to connect theory to practice and therefore develop clinical judgment. Recently, video recording of the simulation scenarios is being incorporated. This qualitative, interpretive description study was conducted to identify whether self-reflection on video-recorded high-fidelity simulation (HFS) scenarios helped prelicensure nursing students to develop clinical judgment. Tanner's clinical judgment model was the framework for this study. Four themes emerged from this study: Confidence, Communication, Decision Making, and Change in Clinical Practice. This study indicated that self-reflection of video-recorded HFS scenarios is beneficial for prelicensure nursing students to develop clinical judgment. [J Nurs Educ. 2016;55(9):522-527.]. Copyright 2016, SLACK Incorporated.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dinh, Nam; Athe, Paridhi; Jones, Christopher

The Virtual Environment for Reactor Applications (VERA) code suite is assessed in terms of capability and credibility against the Consortium for Advanced Simulation of Light Water Reactors (CASL) Verification and Validation Plan (presented herein) in the context of three selected challenge problems: CRUD-Induced Power Shift (CIPS), Departure from Nucleate Boiling (DNB), and Pellet-Clad Interaction (PCI). Capability refers to evidence of required functionality for capturing phenomena of interest while capability refers to the evidence that provides confidence in the calculated results. For this assessment, each challenge problem defines a set of phenomenological requirements against which the VERA software is assessed. Thismore » approach, in turn, enables the focused assessment of only those capabilities relevant to the challenge problem. The evaluation of VERA against the challenge problem requirements represents a capability assessment. The mechanism for assessment is the Sandia-developed Predictive Capability Maturity Model (PCMM) that, for this assessment, evaluates VERA on 8 major criteria: (1) Representation and Geometric Fidelity, (2) Physics and Material Model Fidelity, (3) Software Quality Assurance and Engineering, (4) Code Verification, (5) Solution Verification, (6) Separate Effects Model Validation, (7) Integral Effects Model Validation, and (8) Uncertainty Quantification. For each attribute, a maturity score from zero to three is assigned in the context of each challenge problem. The evaluation of these eight elements constitutes the credibility assessment for VERA.« less

Evaluating intervention fidelity: an example from a high-intensity interval training study.

PubMed

Taylor, Kathryn L; Weston, Matthew; Batterham, Alan M

2015-01-01

Intervention fidelity refers to the degree to which an experimental manipulation has been implemented as intended, but simple, robust methods for quantifying fidelity have not been well documented. Therefore, we aim to illustrate a rigorous quantitative evaluation of intervention fidelity, using data collected during a high-intensity interval training intervention. Single-group measurement study. Seventeen adolescents (mean age ± standard deviation [SD] 14.0 ± 0.3 years) attended a 10-week high-intensity interval training intervention, comprising two exercise sessions per week. Sessions consisted of 4-7 45-s maximal effort repetitions, interspersed with 90-s rest. We collected heart rate data at 5-s intervals and recorded the peak heart rate for each repetition. The high-intensity exercise criterion was ≥ 90% of individual maximal heart rate. For each participant, we calculated the proportion of total exercise repetitions exceeding this threshold. A linear mixed model was applied to properly separate the variability in peak heart rate between- and within-subjects. Results are presented both as intention to treat (including missed sessions) and per protocol (only participants with 100% attendance; n=8). For intention to treat, the median (interquartile range) proportion of repetitions meeting the high-intensity criterion was 58% (42% to 68%). The mean peak heart rate was 85% of maximal, with a between-subject SD of 7.8 (95% confidence interval 5.4 to 11.3) percentage points and a within-subject SD of 15.1 (14.6 to 15.6) percentage points. For the per protocol analysis, the median proportion of high-intensity repetitions was 68% (47% to 86%). The mean peak heart rate was 91% of maximal, with between- and within-subject SDs of 3.1 (-1.3 to 4.6) and 3.4 (3.2 to 3.6) percentage points, respectively. Synthesising information on exercise session attendance and compliance (exercise intensity) quantifies the intervention dose and informs evaluations of treatment fidelity.

Development of a measure of model fidelity for mental health Crisis Resolution Teams.

PubMed

Lloyd-Evans, Brynmor; Bond, Gary R; Ruud, Torleif; Ivanecka, Ada; Gray, Richard; Osborn, David; Nolan, Fiona; Henderson, Claire; Mason, Oliver; Goater, Nicky; Kelly, Kathleen; Ambler, Gareth; Morant, Nicola; Onyett, Steve; Lamb, Danielle; Fahmy, Sarah; Brown, Ellie; Paterson, Beth; Sweeney, Angela; Hindle, David; Fullarton, Kate; Frerichs, Johanna; Johnson, Sonia

2016-12-01

Crisis Resolution Teams (CRTs) provide short-term intensive home treatment to people experiencing mental health crisis. Trial evidence suggests CRTs can be effective at reducing hospital admissions and increasing satisfaction with acute care. When scaled up to national level however, CRT implementation and outcomes have been variable. We aimed to develop and test a fidelity scale to assess adherence to a model of best practice for CRTs, based on best available evidence. A concept mapping process was used to develop a CRT fidelity scale. Participants (n = 68) from a range of stakeholder groups prioritised and grouped statements (n = 72) about important components of the CRT model, generated from a literature review, national survey and qualitative interviews. These data were analysed using Ariadne software and the resultant cluster solution informed item selection for a CRT fidelity scale. Operational criteria and scoring anchor points were developed for each item. The CORE CRT fidelity scale was then piloted in 75 CRTs in the UK to assess the range of scores achieved and feasibility for use in a 1-day fidelity review process. Trained reviewers (n = 16) rated CRT service fidelity in a vignette exercise to test the scale's inter-rater reliability. There were high levels of agreement within and between stakeholder groups regarding the most important components of the CRT model. A 39-item measure of CRT model fidelity was developed. Piloting indicated that the scale was feasible for use to assess CRT model fidelity and had good face validity. The wide range of item scores and total scores across CRT services in the pilot demonstrate the measure can distinguish lower and higher fidelity services. Moderately good inter-rater reliability was found, with an estimated correlation between individual ratings of 0.65 (95% CI: 0.54 to 0.76). The CORE CRT Fidelity Scale has been developed through a rigorous and systematic process. Promising initial testing indicates its value in assessing adherence to a model of CRT best practice and to support service improvement monitoring and planning. Further research is required to establish its psychometric properties and international applicability.

Application of See One, Do One, Teach One Concept in Surgical Training

PubMed Central

Kotsis, Sandra V.; Chung, Kevin C.

2016-01-01

Background The traditional method of teaching in Surgery is known as “See One, Do One, Teach One.” However, many have argued that this method is no longer applicable mainly because of concerns for patient safety. The purpose of this paper is to show that the basis of the traditional teaching method is still valid in surgical training if it is combined with various adult learning principles. Methods We reviewed literature regarding the history of the formation of the surgical residency program, adult learning principles, mentoring, and medical simulation. We provide examples for how these learning techniques can be incorporated into a surgical resident training program. Results The surgical residency program created by Dr. William Halsted remained virtually unchanged until recently with reductions in resident work hours and changes to a competency-based training system. Such changes have reduced the teaching time between attending physicians and residents. Learning principles such as “Experience, Observation, Thinking and Action” as well as deliberate practice can be used to train residents. Mentoring is also an important aspect in teaching surgical technique. We review the different types of simulators: standardized patients, virtual reality applications, and high-fidelity mannequin simulators and the advantages and disadvantages of using them. Conclusions The traditional teaching method of “see one, do one, teach one” in surgical residency programs is simple but still applicable. It needs to evolve with current changes in the medical system to adequately train surgical residents and also provide patients with safe, evidence-based care. PMID:23629100

Military medical modeling and simulation in the 21st century.

PubMed

Moses, G; Magee, J H; Bauer, J J; Leitch, R

2001-01-01

As we enter the 21st century, military medicine struggles with critical issues. One of the most important issues is how to train medical personnel in peace for the realities of war. In April, 1998, The General Accounting Office (GAO) reported, "Military medical personnel have almost no chance during peacetime to practice battlefield trauma care skills. As a result, physicians both within and outside the Department of Defense (DOD) believe that military medical personnel are not prepared to provide trauma care to the severely injured soldiers in wartime. With some of today's training methods disappearing, the challenge of providing both initial; and sustainment training for almost 100,000 military medical personnel is becoming insurmountable. The "training gap" is huge and impediments to training are mounting. For example, restrictions on animal use are increasing and the cost of conducting live mass casualty exercises is prohibitive. Many medical simulation visionaries believe that four categories of medical simulation are emerging to address these challenges. These categories include PC-based multimedia, digital mannequins, virtual workbenches, and total immersion virtual reality (TIVR). The use of simulation training can provide a risk = free realistic learning environment for the spectrum of medical skills training, from buddy-aid to trauma surgery procedures. This will, in turn, enhance limited hands on training opportunities and revolutionize the way we train in peace to deliver medicine in war. High-fidelity modeling will permit manufacturers to prototype new devices before manufacture. Also, engineers will be able to test a device for themselves in a variety of simulated anatomical representations, permitting them to "practice medicine".

Excavator Design Validation

NASA Technical Reports Server (NTRS)

Pholsiri, Chalongrath; English, James; Seberino, Charles; Lim, Yi-Je

2010-01-01

The Excavator Design Validation tool verifies excavator designs by automatically generating control systems and modeling their performance in an accurate simulation of their expected environment. Part of this software design includes interfacing with human operations that can be included in simulation-based studies and validation. This is essential for assessing productivity, versatility, and reliability. This software combines automatic control system generation from CAD (computer-aided design) models, rapid validation of complex mechanism designs, and detailed models of the environment including soil, dust, temperature, remote supervision, and communication latency to create a system of high value. Unique algorithms have been created for controlling and simulating complex robotic mechanisms automatically from just a CAD description. These algorithms are implemented as a commercial cross-platform C++ software toolkit that is configurable using the Extensible Markup Language (XML). The algorithms work with virtually any mobile robotic mechanisms using module descriptions that adhere to the XML standard. In addition, high-fidelity, real-time physics-based simulation algorithms have also been developed that include models of internal forces and the forces produced when a mechanism interacts with the outside world. This capability is combined with an innovative organization for simulation algorithms, new regolith simulation methods, and a unique control and study architecture to make powerful tools with the potential to transform the way NASA verifies and compares excavator designs. Energid's Actin software has been leveraged for this design validation. The architecture includes parametric and Monte Carlo studies tailored for validation of excavator designs and their control by remote human operators. It also includes the ability to interface with third-party software and human-input devices. Two types of simulation models have been adapted: high-fidelity discrete element models and fast analytical models. By using the first to establish parameters for the second, a system has been created that can be executed in real time, or faster than real time, on a desktop PC. This allows Monte Carlo simulations to be performed on a computer platform available to all researchers, and it allows human interaction to be included in a real-time simulation process. Metrics on excavator performance are established that work with the simulation architecture. Both static and dynamic metrics are included.