United Kingdom Mission Training Through Distributed Simulation

This paper presents the findings of a United Kingdom (UK) research program carried out over the last decade. This research has explored the benefits of using networks of simulators for collective training known in the UK as mission training through distributed simulation (MTDS). The paper provides an overview of trials carried out to date, identifies the research issues addressed, and discusses the key findings. The conclusion is that MTDS provides an immersive training environment that has the potential to support not only single service collective training, but also joint and coalition training requirements.     

On the ultra-high-strain rate shock deformation in copper single crystals: multiscale dislocation dynamics simulations

Multiscale dislocation dynamics plasticity (MDDP) calculations are carried out to simulate the mechanical response of copper single crystals that have undergone shock loading at high strain rates ranging from 1?×?10⁶ to 1?×?10¹⁰?s^?1. Plasticity mechanisms associated with both the activation of pre-existing dislocation sources and homogeneous nucleation of glide loops are considered. Our results show that there is a threshold strain rate of 10⁸?s^?1 at which the deformation mechanism changes from source activation to homogeneous nucleation. It is also illustrated that the pressure dependence on strain rate follows a one-fourth power law up to 10⁸?s^?1 beyond which the relationship assumes a one-half power law. The MDDP computations are in good agreement with recent experimental findings and compare well with the predictions of several dislocation-based continuum models.     

How will things be the next time? Self in the construction of future events among school-aged children

This study examined among school-aged children the role of the self in perceived valence changes from the past to the future. Nine- to 11-year-old children (N = 57) recalled positive and negative personal events of various situations and imagined a future personal event involving the same situation following each recall. Children’s self-knowledge was assessed in terms of self-concepts for past, present, and future selves, and self-evaluations for social and cognitive competences. Children who viewed their future selves more positively and those who evaluated their cognitive competence more positively anticipated greater upward (positive) changes and smaller downward (negative) changes in their future academic performance. Children who evaluated their social competence more positively anticipated greater upward changes in their future peer relations. Furthermore, children who anticipated greater upward changes and smaller downward changes in their personal futures exhibited greater well-being. These findings shed new light on the role of self in mental time travel.     

The role of prediction in mental processing: A process approach

Although prediction plays a prominent role in mental processing, we have only limited understanding of how the brain generates and employs predictions. This paper develops a theoretical framework in three steps. First I propose a process model that describes how predictions are produced and are linked to behavior. Subsequently I describe a generative mechanism, consisting of the selective amplification of neural dynamics in the context of boundary conditions. I hypothesize that this mechanism is active as a process engine in every mental process, and that therefore each mental process proceeds in two stages: (i) the formation of process boundary conditions; (ii) the bringing about of the process function by the operation – within the boundary conditions – of a relatively ‘blind’ generative process. Thirdly, from this hypothesis I derive a strategy for describing processes formally. The result is a multilevel framework that may also be useful for studying mental processes in general.     

Performance and presence with head-movement produced motion parallax in simulated driving

Driving simulator studies can reveal relevant and valid aspects of driving behavior, but underestimation of distance and speed can negatively affect the driver’s performance, such as in performance of overtaking. One possible explanation for the underestimation of distance and speed is that two-dimensional projection of the visual scene disrupts the monocular-based illusory depth because of conflicting binocular and monocular information of depth. A possible solution might involve the strengthening of the monocular information so that the binocular information becomes less potent. In the present study, we used an advanced high-fidelity driving simulator to investigate whether adding the visual depth information of motion parallax from head movement affects sense of presence, judgment of distance and speed, and performance measures coupled with overtaking. The simulations included two types of driving scenario in which one was urban and the other was rural. The main results show no effect of this head-movement produced motion parallax on sense of presence, head movement, time to collision, distance judgment, or speed judgment. However, the results show an effect on lateral positioning. When initiating the overtaking maneuver there is a lateral positioning farther away from the road center as effect of the motion parallax in both types of scenario, which can be interpreted as indicating use of naturally occurring information that change behavior at overtaking. Nevertheless, only showing tendencies of effects, absent is any clear additional impact of this motion parallax in the simulated driving.     

Human hip–ankle coordination emerging from multisensory feedback control

Human sensorimotor control involves inter-segmental coordination to cope with the complexity of a multi-segment system. The combined activation of hip and ankle muscles during upright stance represents the hip–ankle coordination. This study postulates that the coordination emerges from interactions on the sensory levels in the feedback control. The hypothesis was tested in a model-based approach that compared human experimental data with model simulations. Seven subjects were standing with eyes closed on an anterior–posterior tilting motion platform. Postural responses in terms of angular excursions of trunk and legs with respect to vertical were measured and characterized using spectral analysis. The presented control model consists of separate feedback modules for the hip and ankle joints, which exchange sensory information with each other. The feedback modules utilize sensor-derived disturbance estimates rather than ‘raw’ sensory signals. The comparison of the human data with the simulation data revealed close correspondence, suggesting that the model captures important aspects of the human sensory feedback control. For verification, the model was re-embodied in a humanoid robot that was tested in the human laboratory. The findings show that the hip–ankle coordination can be explained by interactions between the feedback control modules of the hip and ankle joints.     

认知判断中手部动作模拟的fMRI研究

该研究采用功能磁共振成像技术,考察不同条件下进行工具认知判断时手部姿势对认知判断的影响及动作模拟的神经机制。实验发现：手部姿势存在显著的主效应,冲突手部姿势条件下反应时最慢,且冲突手部姿势条件下与不冲突手部姿势条件下、自然状态条件下反应时存在显著差异,自然状态条件与不冲突手部姿势条件下反应时不存在显著差异。另外,f MRI成像结果发现,额中回、额下回、顶下小叶以及辅助运动区在自然状态下有显著激活,表明个体在进行认知判断过程中有动作模拟过程;海马结构、扣带回及楔前叶等与记忆有关的脑区有显著激活,表明身体经验在认知过程的作用。总的研究表明,不同的手部姿势状态对认知判断有不同影响,冲突手部姿势会对动作模拟产生干扰作用,手部动作模拟的神经机制主要涉及镜像神经元区,且在认知判断时存在具身效应。     

K-means、潜在类别模型和混合Rasch模型的比较

基于模拟研究比较了K-means方法、潜在类别模型和混合Rasch模型在二分外显变量情境下的聚类效果.结果表明：（1）潜在类别数量、变量数量、样本量、样本平衡和变量间相关对K-means方法、潜在类别模型和混合Rasch模型的分类准确性均有影响且因素间的交互作用存在;（2）除了在2个潜在类别的样本不平衡条件下K-means方法表现较差外,在其他条件下与潜在类别模型和混合Rasch模型的表现相当;（3）混合Rasch模型的分类一致性在2个潜在类别的情境下要好于潜在类别模型,但是在4个潜在类别的情境下要差于潜在类别模型.     

Determinants of Integration and Confrontation in Internal Dialogues

Interest in the distinction between integrative and confrontational internal dialogues has been growing, as research suggests numerous positive functions of the former compared to the latter. The article proposes a theoretical approach to integration and confrontation in internal dialogue and an empirical method of measuring these processes. Exploratory research is also presented that seeks to identify personality‐related and situational determinants of integration and confrontation in internal dialogue simulating social relationships. Canonical correlation analysis did not establish personality determinants but it did reveal situational determinants (understood as cognitive interpretation of the enacted situation) behind integration and confrontation in internal dialogue. Perceiving the internal interlocutor as similar to the dialogue's author is associated with the author's integrative attitude. An increase in the wishfulness of the dialogue is accompanied by an increase in the author's confrontational attitude and the interlocutor's integrative attitude.