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In this study, we will explore how the indegree centrality of a trait can change the strength of the degree to which participants’ self-ratings become closer to target ratings after simulation.

In this study, we will explore how the indegree centrality of a trait can change the strength of the degree to which participants’ self-ratings become closer to target ratings after simulation.

This line of studies looks to explore potential avenues of application for simulation induced malleability (SIM), in which simulating another individual can change self-knowledge. In this study, we will explore the role of pre-simulation activation of self-knowledge on different targets of simulation (similar others vs. dissimilar others).

This line of studies looks to explore potential avenues of application for simulation induced malleability (SIM), in which simulating another individual can change self-knowledge. In this study, we will explore the role of pre-simulation activation of self-knowledge on different targets of simulation (similar others vs. dissimilar others).

This line of studies looks to explore potential avenues of application for simulation induced malleability (SIM), in which simulating another individual can change self-knowledge. In this study, we will explore the role of pre-simulation activation of self-knowledge on different targets of simulation (similar others vs. dissimilar others).

Six charges are conidered, using symmerty to reduce the number of variables to three charges three on each Side.

Increasing awareness about the available virtual care options for the nursing profession has become essential in a digital society. This can be achieved through the integration of teleconsultation into undergraduate nursing curricula, thereby providing a solid foundation for the incorporation of these innovative practices into patient care. Considering that simulation is a method of testing, experimenting, or rehearsing that seeks to artificially or controlledly reproduce real situations or processes. This pedagogical strategy, in healthcare educational institutions, occurs both in simulation laboratories and in the actual care environment, where scenarios are recreated to provide practical learning. Clinical simulation allows students to develop skills such as clinical reasoning, decision-making, and action sequencing.

Basic OS Scratch builded

This paper presents the results of a one-dimensional numerical simulation of the transient chilldown of a vertical stainless steel tube with liquid nitrogen. The direction of flow is downward (with gravity) through the tube. Heat transfer correlations for film, transition, and nucleate boiling, as well as critical heat flux, rewetting temperature, and the temperature at the onset of nucleate boiling were used to model the convection to the tube wall. Chilldown curves from the simulations were compared with data from 55 recent liquid nitrogen chilldown experiments. With these new correlations the simulation is able to predict the time to rewetting temperature and time to onset of nucleate boiling to within 25% for mass fluxes ranging from 61.2 to 1150 kg/(sq m s), inlet pressures from 175 to 817 kPa, and subcooled inlet temperatures from 0 to 14 K below the saturation temperature.

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Concordant computation is a circuit-based model of quantum computation for mixed states, that assumes that all correlations within the register are discord-free (i.e. the correlations are essentially classical) at every step of the computation. The question of whether concordant computation always admits efficient simulation by a classical computer was first considered by B. Eastin in quant-ph/1006.4402v1, where an answer in the affirmative was given for circuits consisting only of one- and two-qubit gates. Building on this work, we develop the theory of classical simulation of concordant computation. We present a new framework for understanding such computations, argue that a larger class of concordant computations admit efficient simulation, and provide alternative proofs for the main results of quant-ph/1006.4402v1 with an emphasis on the exactness of simulation which is crucial for this model. We include detailed analysis of the arithmetic complexity for solving equations in the simulation, as well as extensions to larger gates and qudits. We explore the limitations of our approach, and discuss the challenges faced in developing efficient classical simulation algorithms for all concordant computations.

Extensive research is being done toward the development of ultra-low-emissions combustors for aircraft gas turbine engines. However, these combustors have an increased susceptibility to thermoacoustic instabilities. This type of instability was recently observed in an advanced, low emissions combustor prototype installed in a NASA Glenn Research Center test stand. The instability produces pressure oscillations that grow with increasing fuel/air ratio, preventing full power operation. The instability behavior makes the combustor a potentially useful test bed for research into active control methods for combustion instability suppression. The instability behavior was characterized by operating the combustor at various pressures, temperatures, and fuel and air flows representative of operation within an aircraft gas turbine engine. Trends in instability behavior versus operating condition have been identified and documented, and possible explanations for the trends provided. A simulation developed at NASA Glenn captures the observed instability behavior. The physics-based simulation includes the relevant physical features of the combustor and test rig, employs a Sectored 1-D approach, includes simplified reaction equations, and provides time-accurate results. A computationally efficient method is used for area transitions, which decreases run times and allows the simulation to be used for parametric studies, including control method investigations. Simulation results show that the simulation exhibits a self-starting, self-sustained combustion instability and also replicates the experimentally observed instability trends versus operating condition. Future plans are to use the simulation to investigate active control strategies to suppress combustion instabilities and then to experimentally demonstrate active instability suppression with the low emissions combustor prototype, enabling full power, stable operation.

A damage model for the simulation of delamination propagation under high-cycle fatigue loading is proposed. The basis for the formulation is a cohesive law that links fracture and damage mechanics to establish the evolution of the damage variable in terms of the crack growth rate dA/dN. The damage state is obtained as a function of the loading conditions as well as the experimentally-determined coefficients of the Paris Law crack propagation rates for the material. It is shown that by using the constitutive fatigue damage model in a structural analysis, experimental results can be reproduced without the need of additional model-specific curve-fitting parameters.

Time-dependent Navier-Stokes flow simulations have been carried out for a UH-60 rotor with simplified hub in forward flight and hover flight conditions. Flexible rotor blades and flight trim conditions are modeled and established by loosely coupling the OVERFLOW Computational Fluid Dynamics (CFD) code with the CAMRAD II helicopter comprehensive code. High order spatial differences, Adaptive Mesh Refinement (AMR), and Detached Eddy Simulation (DES) are used to obtain highly resolved vortex wakes, where the largest turbulent structures are captured. Special attention is directed towards ensuring the dual time accuracy is within the asymptotic range, and verifying the loose coupling convergence process using AMR. The AMR/DES simulation produced vortical worms for forward flight and hover conditions, similar to previous results obtained for the TRAM rotor in hover. AMR proved to be an efficient means to capture a rotor wake without a priori knowledge of the wake shape.

Recently, the computer program 'A Computer Solution for Hydrostatic Bearings with Variable Film Thickness,' used to design the hydrostatic bearing of the 70-meter antennas, was modified to improve the accuracy with which the program predicts the film height profile and oil pressure distribution between the hydrostatic bearing pad and the runner. This article presents a description of the modified computer program, the theory upon which the computer program computations are based, computer simulation results, and a discussion of the computer simulation results.

Implementation of the IPv6 protocols stack has become a fact in military networks. Although the IPv6 protocol is very efficient but all problems with its adaptation to military networks have not been resolved yet. The assurance of necessary level of quality of services in changing condition of available bandwidth is an example of such a problem. Additionally, current military networks also use narrowband links, especially in their radio segments. The problem is serious, because the IP protocols suite (and thus IPv6) has been elaborated and developed for wideband networks and for carrying the non real-time traffic. Thus, for instance, the voice or video can be provided using IPv6, but a minimum bandwidth is required or advanced QoS supporting mechanism have to be implemented. The research carried out by the FKIE, the Computer Science Department of the University of Bonn and the Polish MCI/MUT teams are related to developing of IPv6 QoS mechanism that are well suited to the low bandwidth requirements in military networks. These mechanisms have been implemented both in real-life software and in simulation environments. The first experiments show their proper behavior in IPv6-based military networks with limited bandwidth links. The paper covers a description of modeling and simulation of proposed QoS mechanisms. The authors have concentrated on an analysis of the service multiplexing and priority handling procedures. The aim of this effort is to evaluate bandwidth utilization that allows increasing the information flows. Achieved results give a possibility of using simulation models for testing of new developed or modified IPv6 mechanisms for wider tactical networks.

This study incorporated two approaches to determine the thermal conductivity of nanocomposite material using numerical modeling and simulation. The first was to look at the nanocomposite material at the macro level using a continuum model. The second approach broke the problem down to the atomic level and addressed the inter-atomic reactions using the Molecular Dynamics model. The continuum model was used to determine the optimal placement and alignment of the nanoparticles within a nanocomposite to provide the largest enhancement of thermal conductivity for the composite. During this process the effects of the particle size and spacing were investigated to determine the function that interparticle spacing and particle size plays in the thermal conductivity of the composite. The Molecular Dynamics model was also used to calculate the thermal conductivity of nanocomposites given the thermal conductivity of the nanoparticles and the base material.

It is estimated that more than 500,000 tons of obsolete and unwanted conventional weapons exists in the United States. The disposal of these unexploded ordnances, in an environmentally sound and cost effective way, is of tantamount importance. Open-air burning and open-air detonation (OB/OD) are two of the most widely used methods to dispose of these unwanted energetic materials. This report describes our efforts to improve the environmental safety of OB/OD operations through the design and testing of a new, large-scale, partially confined facility that minimizes the adverse affects of far field noise and maximizes the afterburn of explosive byproducts. Several designs were evaluated by a series of axisymmetric, time-dependent numerical simulations using FAST3D, a Flux-Corrected Transport based code optimized for parallel processing. The simulations are used to investigate various facility geometries and shapes and charge size, shape, and placement to determine combinations that result in acceptable detonations. Results from the simulations were used to determine the structural response of the facility to the initial blast.

A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent optical dipole forces applied to an ion crystal create long-range effective spin-spin interactions and allow the simulation of spin Hamiltonians that possess nontrivial phases and dynamics. Here we show how appropriate design of laser fields can provide for arbitrary multidimensional spin-spin interaction graphs even for the case of a linear spatial array of ions. This scheme uses currently existing trap technology and is scalable to levels where classical methods of simulation are intractable.

Standardization of interoperable and multinational training and that training is a requirement for current international missions. The simulation has had a preponderant focus on this normalization Pre-mission or pre-deployment training in military health is for health teams, but also all elements of the force according to their skills. The objective of this study is to map evidence about simulation in health education of the army, during the deployment. The researsh question is: How is simulation used in military health education in the deployment of the Army military personnel?

This work outlines a procedure for simulating the flow field within multistage turbomachinery which includes the effects of unsteadiness, compressibility, and viscosity. The associated modeling equations are the average passage equation system which governs the time-averaged flow field within a typical passage of a blade row embedded within a multistage configuration. The results from a simulation of a low aspect ratio stage and a one-half turbine will be presented and compared with experimental measurements. It will be shown that the secondary flow field generated by the rotor causes the aerodynamic performance of the downstream vane to be significantly different from that of an isolated blade row.

Crew effectiveness is a joint product of the piloting skills, attitudes, and personality characteristics of team members. As obvious as this point might seem, both traditional approaches to optimizing crew performance and more recent training development highlighting crew coordination have emphasized only the skill and attitudinal dimensions. This volume is the first in a series of papers on this simulation. A subsequent volume will focus on patterns of communication within crews. The results of a full-mission simulation research study assessing the impact of individual personality on crew performance is reported. Using a selection algorithm described in previous research, captains were classified as fitting one of three profiles along a battery of personality assessment scales. The performances of 23 crews led by captains fitting each profile were contrasted over a one-and-one-half-day simulated trip. Crews led by captains fitting a positive Instrumental-Expressive profile (high achievement motivation and interpersonal skill) were consistently effective and made fewer errors. Crews led by captains fitting a Negative Expressive profile (below average achievement motivation, negative expressive style, such as complaining) were consistently less effective and made more errors. Crews led by captains fitting a Negative Instrumental profile (high levels of competitiveness, verbal aggressiveness, and impatience and irritability) were less effective on the first day but equal to the best on the second day. These results underscore the importance of stable personality variables as predictors of team coordination and performance.

An electric arc heater was operated at 800 amperes and 100,000 pa (1 atm) with hydrogen, helium, and two mixtures of hydrogen and helium. A VUV-scanning monochromator was used to record the spectra from an end view while a second spectrometer was used to determine the plasma temperature using hydrogen continuum radiation at 562 nm. Except for pure helium, the plasma temperature was found to be too low to produce significant helium radiation, and the measured spectra were primarily the hydrogen spectra with the highest intensity in the pure hydrogen case. A radiation computer code was used to compute the spectra for comparison to the measurements and to extend the study to simulation of outer planet entry radiation. Conductive cooling prevented ablation of phenolic carbon material samples mounted inside the arc heater during a cursory attempt to produce radiation absorption by ablation gases.

Time simulation of flutter, involving large local structural changes, is formulated with a state-space model that is based on a relatively small number of generalized coordinates. Free-free vibration modes are first calculated for a nominal finite-element model with relatively large fictitious masses located at the area of structural changes. A low-frequency subset of these modes is then transformed into a set of structural modal coordinates with which the entire simulation is performed. These generalized coordinates and the associated oscillatory aerodynamic force coefficient matrices are used to construct an efficient time-domain, state-space model for a basic aeroelastic case. The time simulation can then be performed by simply changing the mass, stiffness, and damping coupling terms when structural changes occur. It is shown that the size of the aeroelastic model required for time simulation with large structural changes at a few apriori known locations is similar to that required for direct analysis of a single structural case. The method is applied to the simulation of an aeroelastic wind-tunnel model. The diverging oscillations are followed by the activation of a tip-ballast decoupling mechanism that stabilizes the system but may cause significant transient overshoots.

NASA Glenn Research Center, ONERA, and the University of Illinois are conducting a major research program whose goal is to improve our understanding of the aerodynamic scaling of ice accretions on airfoils. The program when it is completed will result in validated scaled simulation methods that produce the essential aerodynamic features of the full-scale iced-airfoil. This research will provide some of the first, high-fidelity, full-scale, iced-airfoil aerodynamic data. An initial study classified ice accretions based on their aerodynamics into four types: roughness, streamwise ice, horn ice, and spanwise-ridge ice. Subscale testing using a NACA 23012 airfoil was performed in the NASA IRT and University of Illinois wind tunnel to better understand the aerodynamics of these ice types and to test various levels of ice simulation fidelity. These studies are briefly reviewed here and have been presented in more detail in other papers. Based on these results, full-scale testing at the ONERA F1 tunnel using cast ice shapes obtained from molds taken in the IRT will provide full-scale iced airfoil data from full-scale ice accretions. Using these data as a baseline, the final step is to validate the simulation methods in scale in the Illinois wind tunnel. Computational ice accretion methods including LEWICE and ONICE have been used to guide the experiments and are briefly described and results shown. When full-scale and simulation aerodynamic results are available, these data will be used to further develop computational tools. Thus the purpose of the paper is to present an overview of the program and key results to date.

The charge-spot technique for modeling the static electric forces acting between charged fine particles entails treating electric charges on individual particles as small sets of discrete point charges, located near their surfaces. This is in contrast to existing models, which assume a single charge per particle. The charge-spot technique more accurately describes the forces, torques, and moments that act on triboelectrically charged particles, especially image-charge forces acting near conducting surfaces. The discrete element method (DEM) simulation uses a truncation range to limit the number of near-neighbor charge spots via a shifted and truncated potential Coulomb interaction. The model can be readily adapted to account for induced dipoles in uncharged particles (and thus dielectrophoretic forces) by allowing two charge spots of opposite signs to be created in response to an external electric field. To account for virtual overlap during contacts, the model can be set to automatically scale down the effective charge in proportion to the amount of virtual overlap of the charge spots. This can be accomplished by mimicking the behavior of two real overlapping spherical charge clouds, or with other approximate forms. The charge-spot method much more closely resembles real non-uniform surface charge distributions that result from tribocharging than simpler approaches, which just assign a single total charge to a particle. With the charge-spot model, a single particle may have a zero net charge, but still have both positive and negative charge spots, which could produce substantial forces on the particle when it is close to other charges, when it is in an external electric field, or when near a conducting surface. Since the charge-spot model can contain any number of charges per particle, can be used with only one or two charge spots per particle for simulating charging from solar wind bombardment, or with several charge spots for simulating triboelectric charging. Adhesive image-charge forces acting on charged particles touching conducting surfaces can be up to 50 times stronger if the charge is located in discrete spots on the particle surface instead of being distributed uniformly over the surface of the particle, as is assumed by most other models. Besides being useful in modeling particulates in space and distant objects, this modeling technique is useful for electrophotography (used in copiers) and in simulating the effects of static charge in the pulmonary delivery of fine dry powders.

The U.S. Army Tank and Automotive Research, Development, and Engineering Center (TARDEC), in collaboration with the U.S. Army Research Laboratory (ARL), Human Research and Engineering Directorate, is using TARDEC's Ride Motion Simulator (RMS) to address design requirements for future force systems. Future force systems are envisioned to be lightweight, highly-mobile vehicles that will utilize complex information systems to ensure, for example, both Soldier survivability and system lethality. One of the major challenges and program risks identified by Future Combat Systems is that, in these future systems, Soldiers will need to be able to maintain their high levels of performance even when their vehicles are moving over terrain. This motion effects challenge involves a host of problems including, but not limited to: the presentation of critical information in an understandable way, the implementation of control devices that allow the successful completion of mission Operations, and the reduction of potential disorientation and motion sickness, all of which will be adversely affected when Soldiers are bounced around in moving vehicles. Making decisions on how to deal with motion effects issues is all the more difficult because potentially crucial design choices must be made for vehicles whose ride characteristics are still unknown. Through the combined efforts of researchers at TARDEC and ARL, a systematic approach using motion-base simulation is being implemented to address some of these challenges.

The motivation for the Model-based Integrated Simulation (MILAN) project is to develop an extensible modeling, simulation, and design space exploration framework for the design of latency and energy efficient embedded systems for signal processing applications. Design of embedded systems requires minimization of energy dissipation (to maximize battery life) while meeting a given latency constraint (typically real-time constraints). While until now Application Specific Integrated Circuits (ASICs) were considered the primary choice for low power high performance embedded systems, the recent advances in the design of general purpose processors (GPP), digital signal processors (DSP), field programmable gate arrays (FPGAs), and memories have provided viable commercial-off-the-self (COTS) alternatives to ASICs. These devices are designed using low-leakage process and support a number of low power operating and standby states, dynamic voltage and frequency scaling, among others to support energy optimization. In the MILAN project, we focus on signal processing applications that process a stream of input frames while meeting a given latency constraint for the processing of a single frame. MILAN is a joint effort by the University of Southern California and Vanderbilt University and is supported by the DARPA Power Aware Computing and Communication Program.

A software simulation of long constraint length Viterbi decoders was developed. This software closely follows the hardware architecture that was chosen for the Very Large Scale Integration implementation. The program is used to validate the design of the decoder and to generate test vectors for the VLSI circuits.

Reusability and composability (R&C) are two important quality characteristics that have been very difficult to achieve in the Modelling and Simulation (M&S) discipline. Reuse provides many technical and economical benefits. Composability has been increasingly crucial for M&S of a system of systems, in which disparate systems are composed with each other. The purpose of this paper is to describe how R&C can be achieved by using a simulation conceptual model (CM) in a community of interest (COI). We address R&C in a multifaceted manner covering many M&S areas (types). M&S is commonly employed where R&C are very much needed by many COIs. We present how a CM developed for a COI can assist in R&C for the design of any type of large-scale complex M&S application in that COI. A CM becomes an asset for a COI and offers significant economic benefits through its broader applicability and more effective utilization.

Methods of modelling probabilistic components which are not adequately represented by the standard continuous distributions (such as normal, gamma, and Weibull) are surveyed. The methods are categorized as systems of distributions, approximations to the cumulative distribution function, and four-parameter distributions. Emphasis is on generality, determination of appropriate parameter values, and random variate generation. (Author)

This report provides the specifications for a fast and comprehensive simulation of tactical nuclear war and conventional operations under the threat of nuclear war. The model focus is on military decision-making under specified political constraints on the employment of nuclear weapons in a theater. Means are provided for evaluating the military effect of political constraints command-control-communications, target acquisition, intelligence, combined nuclear-conventional operations, conventional attack of nuclear targets, and air-ground interactions.

The purpose of this investigation were twofold: first, to determine whether accurate force and moment data could be obtained during hypersonic wind tunnel tests of a model with a scramjet exhaust flow simulation that uses a representative nonwatercooled, flow-through balance; second, to analyze temperature time histories on various parts of the balance to address thermal effects on force and moment data. The tests were conducted in the NASA Langley Research Center 20-Inch Mach 6 Wind Tunnel at free-stream Reynolds numbers ranging from 0.5 to 7.4 x 10(exp 6)/ft and nominal angles of attack of -3.5 deg, 0 deg, and 5 deg. The simulant exhaust gases were cold air, hot air, and a mixture of 50 percent Argon and 50 percent Freon by volume, which reached stagnation temperatures within the balance of 111, 214, and 283 F, respectively. All force and moment values were unaffected by the balance thermal response from exhaust gas simulation and external aerodynamic heating except for axial-force measurements, which were significantly affected by balance heating. This investigation showed that for this model at the conditions tested, a nonwatercooled, flow-through balance is not suitable for axial-force measurements during scramjet exhaust flow simulation tests at hypersonic speeds. In general, heated exhaust gas may produce unacceptable force and moment uncertainties when used with thermally sensitive balances.

The cooperative effort being carried out under the agreements of the United States-Israel Memorandum of Understanding is discussed. Two different models of the AH-64 Apache Helicopter, which may differ in their approach to modeling the main rotor, are presented. The first model, the Blade Element Model for the Apache (BEMAP), was developed at Ames Research Center, and is the only model of the Apache to employ a direct blade element approach to calculating the coupled flap-lag motion of the blades and the rotor force and moment. The second model was developed at the Technion-Israel Institute of Technology and uses an harmonic approach to analyze the rotor. The approach allows two different levels of approximation, ranging from the 'first harmonic' (similar to a tip-path-plane model) to 'complete high harmonics' (comparable to a blade element approach). The development of the two models is outlined and the two are compared using available flight test data.

Modded version of GT2, named GT2+

Zero-temperature density functional theory (DFT), density functional theory molecular dynamics (DFT-MD), and classical molecular dynamics using polarizable force fields (PFF-MD) are employed to evaluate the influence of Lithium ion on the structure, transport, and electrochemical stability of three potential ionic liquid electrolytes: N--methyl-N-butylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([pyr14][TFSI]), N--methyl-N-propylpyrrolidinium bis(fluorosulfonyl)imide ([pyr13][FSI]), and 1-ethyl-3--methylimidazolium boron tetrafluoride ([EMIM][BF4]). We characterize the Lithium ion solvation shell through zero-temperature DFT simulations of [Li(Anion)sub n](exp n-1) -clusters, DFT-MD simulations of isolated lithium ions in small ionic liquid systems, and PFF-MD simulations with high Li-doping levels in large ionic liquid systems. At low levels of Li-salt doping, highly stable solvation shells having 2-3 anions are seen in both [pyr14][TFSI] and [pyr13][FSI], while solvation shells with 4 anions dominate in [EMIM][BF sub 4]. At higher levels of doping, we find the formation of complex Li-network structures that increase the frequency of 4 anion-coordinated solvation shells. A comparison of computational and experimental Raman spectra for a wide range of [Li(Anion) sub n](exp n -1) - clusters shows that our proposed structures are consistent with experiment. We estimate the ion diffusion coefficients and quantify both size and simulation time effects. We find estimates of lithium ion diffusion are a reasonable order of magnitude and can be corrected for simulation time effects. Simulation size, on the other hand, is also important, with diffusion coefficients from long PFF-MD simulations of small cells having 20-40% error compared to large-cell values. Finally, we compute the electrochemical window using differences in electronic energy levels of both isolated cation/anion pairs and small ionic liquid systems with Li-salt doping. The single pair and liquid-phase systems provide similar estimates of electrochemical window, while Li-doping in the liquid-phase systems results in electrochemical windows little changed from the neat systems. Pure and hybrid functionals systematically provide an upper and lower bound, respectively, to the experimental electrochemical window for the systems studied here.

Stochastic (probabilistic) forecasting techniques give forecasters a means to transmit information about certainty and a range of forecast possibilities to operational decision makers. Previous studies have shown value in probabilistic forecasting through series of independent hypothetical events, or through comparative period forecasts. This thesis demonstrates the value of stochastic forecasting through a series of operational events, in the context of a Strike Warfare campaign in the Weather Impact Assessment Tool (WIAT), a campaign simulator. Simulated ensemble members and probability files were created to study six weather parameters and their impacts on various Strike Warfare missions. Tests were run comparing deterministic and stochastic forecasts, incorporating varying levels of forecast error and sampled probability thresholds. Metrics within and external to WIAT were employed to analyze the results of the forecasting strategies. Constraints in WIAT's structure and campaign modeling yielded results that suggest, but do not definitively prove, enhanced campaign performance as a result of incorporating probabilistic forecasting. Programming adjustments to WIAT are recommended in order to provide a higher-quality test bed for future studies of both deterministic and stochastic forecasting techniques.

The purpose of this study was to evaluate the parallel processing impact of MIMD (Multiple-Instruction Multiple-Data Path) computers on Flight Simulation Software. Basic mathematical functions and arithmetic expressions from typical Flight Simulation Software were selected and run on a MIMD computer to evaluate the improvement in execution time that results from the parallel architecture of this type of computer. Recommendations as to the types of tasks which are optimally suitable for this computer architecture are made, together with the improvement in execution speed to be expected. (Author)

As computer speeds and capabilities increase, models which used to require hours or days to execute may now be executed in minutes. While the analyst soon may be able to contemplate doing hundreds of runs in a day, the lack of suitable techniques for analyzing the vast output produced by this many runs is evident. One objective of the IDA Advanced Technology Combat Simulation Project is to develop new techniques for analyzing such output. The major product of this research project to date has been the development of new methodology for conducting and analyzing the results of large scale parametric analyses based on computerized models. This response surface methodology comprises three components: the ability to perform hundreds of model excursions rapidly, an advanced graphical analysis system developed by IDA, and a collection of model specific input and output processors. This Graphical Analysis System incorporates advanced topological concepts and algorithms in a sophisticated application of Mathematical and provides the ability to visualize any multidimensional data set. Using the response surface methodology, the analyst can better perform model verification and validation, can quickly home in on key model sensitivities and can more thoroughly convey the results of an analysis to a broad audience.

This line of studies looks to explore potential avenues of application for simulation induced malleability (SIM), in which simulating another individual can change self-knowledge. In this study, we will explore whether naturalistically simulating another individual can change self-ratings on competence for women.

The purpose of this pilot study was to explore student perceptions and outcomes surrounding the use of a labor and delivery simulation as a midterm exam in a maternal-newborn lecture course. An exploratory case study design was used to gain a holistic view of the simulation experience. Data from focus groups, written debriefings, simulation scoring rubrics, student course evaluations, and other course exams were analyzed using Stake's case study method. Qualitative analysis revealed four themes: confidence, fairness, reliability, and team effort. Students were able to accurately grade the performance of their group as a whole and complete a group self-debriefing, but quantitative analysis showed that the group scores were significantly higher than other individual course grades. The findings suggested that the group simulation was an authentic assessment of teamwork, but not individual performance. Future research is needed to determine what role simulation and collaborative testing should play in pre-licensure education.

This thesis presents a dynamic route selection model for the ground combat simulation environment. An optimal route is selected for an advancing combat unit, taking known enemy location(s) into consideration. The selected route is in the form suitable for a single vehicle movement. The model is explained in detail, the complete listing is displayed and some results from exercising the model are presented and discussed. The exercise was conducted on a digitized terrain, yet with simple modification it can work with functional terrain as well. The modification is explained, along with others that may be of interest to users. Conceptual methods of expanding the model to consider unit formation in the route selection process is presented. A number of ways to enrich this routine, namely to consider enemy elements instead of units, diversification of enemy threats, etc., are also discussed. (Author)

The three-dimensional simulation code MAFIA was used to compute the cold-test parameters - frequency-phase dispersion, beam on-axis interaction impedance, and attenuation - for two types of traveling-wave tube (TWT) slow-wave circuits. The potential for this electromagnetic computer modeling code to reduce the time and cost of TWT development is demonstrated by the high degree of accuracy achieved in calculating these parameters. Generalized input files were developed for ferruled coupled-cavity and TunneLadder slow-wave circuits. These files make it easy to model circuits of arbitrary dimensions. The utility of these files was tested by applying each to a specific TWT slow-wave circuit and comparing the results with experimental data. Excellent agreement was obtained.

Cerebrovascular diseases such as brain aneurysms are a primary cause of adult disability. The flow dynamics in brain arteries, both during periods of rest and increased activity, are known to be a major factor in the risk of aneurysm formation and rupture. The precise relation is however still an open field of investigation. We present an automated ensemble simulation method for modelling cerebrovascular blood flow under a range of flow regimes. By automatically constructing and performing an ensemble of multiscale simulations, where we unidirectionally couple a 1D solver with a 3D lattice-Boltzmann code, we are able to model the blood flow in a patient artery over a range of flow regimes. We apply the method to a model of a middle cerebral artery, and find that this approach helps us to fine-tune our modelling techniques, and opens up new ways to investigate cerebrovascular flow properties.

Prior studies have demonstrated that episodic simulation (e.g., in the form of a guided imagination exercise that illustrates future or hypothetical scenarios) can increase patient decision-making, prosocial intentions and behaviors, perceived risk, and future-oriented thinking (Sinclair et al., 2021; Gaesser & Schacter, 2014; Gaesser et al., 2020; Bulley et al., 2016; Schacter et al., 2008; Lee et al., 2020). In particular, prior studies have shown benefits of two-part interventions: episodic simulation can enhance subsequent learning from feedback in intervention tasks that correct misconceptions about risk (Sinclair et al., 2021) or the impact of climate action (Lee et al., 2020). In a prior study, we found that an episodic simulation exercise (imagining oneself experiencing a negative future scenario that could arise from climate change) increased intentions to engage in pro-environmental behaviors and influenced emotions related to climate change (e.g., increasing anger and perceived risk). In this prior study, we also tested multiple other intervention strategies and identified other approaches that had similar or complementary effects (e.g., increasing the perceived impact of climate action, increasing hope and self-efficacy, correcting misconceptions about which mitigation actions matter most). In the present study, we aim to replicate our prior findings and test novel multi-part interventions, combining strategies that target different psychological mechanisms. On the basis of prior research (described above), we expect that episodic simulation will induce a state that will enhance the effectiveness of subsequent intervention tasks.

A scoping review

Bell's theorem implies that the outcomes of local measurements on two maximally entangled systems cannot be simulated without classical communication between the parties. The communication cost is finite for n Bell states, but it grows exponentially in n. Three simple protocols are presented that provide approximate simulations for low-dimensional entangled systems and require a linearly growing amount of communication. We have tested them by performing some simulations for a family of measurements. The maximal error is less than 1% in three dimensions and grows sublinearly with the number of entangled bits in the range numerically tested. One protocol is the multidimensional generalization of the exact Toner-Bacon [Phys. Rev. Lett. 91, 187904 (2003)] model for a single Bell state. The other two protocols are generalizations of an alternative exact model, which we derive from the Kochen-Specker [J. Math. Mech. 17, 59 (1967)] scheme for simulating single-qubit measurements. These protocols can give some indication for finding optimal one-way communication protocols that classically simulate entanglement and quantum channels. Furthermore they can be useful for deciding if a quantum communication protocol provides an advantage on classical protocols.

The objective of this study is to assess the applicability of modern computer and communication technology to the problems of testbed design and operation. The work is being conducted in two phases. Phase I, reported here, was undertaken to gather and assimilate information on several DOD testbeds. Phase II consists of a critical analysis of problem areas in networking simulations, the identification of simulation network requirements, and the development of a preliminary network design description. (Author)

The long-term goal of this project is to develop a coupled ocean-estuary simulation tool that will consist of the Regional Oceanic Modeling System (ROMS) and the nonhydrostatic, unstructured-grid SUNTANS model, in order to study the interaction of coastal regions with estuaries. The scientific goal will be to understand the dynamics of ocean-estuary exchange between San Francisco Bay and the coastal Pacific Ocean, with ROMS simulating the coastal Pacific Ocean, and SUNTANS simulating San Francisco Bay.