Three-dimensional Multispecies Simulation of the Solar Wind Interaction with Mars Under Different Interplanetary Magnetic Field Orientations

Without the intrinsic magnetic field, the solar wind interaction with Mars can be significantly different from the interaction with Earth and other magnetized planets. In this paper, we investigate how a global configuration of the magnetic structures, consisting of the bow shock, the induced magnetosphere, and the magnetotail, is modulated by the interplanetary magnetic field (IMF) orientation. A 3D multispecies numerical model is established to simulate the interaction of solar wind with Mars under different IMF directions. The results show that the shock size including the subsolar distance and the terminator radius increases with Parker spiral angle, as is the same case with the magnetotail radius. The location and shape of the polarity reversal layer and inverse polarity reversal layer in the induced magnetotail are displaced to the y < 0 sector for a nonzero flow-aligned IMF component, consistent with previous analytical solutions and observations. The responses of the Martian global magnetic configuration to the different IMF directions suggest that the external magnetic field plays an important role in the solar wind interaction with unmagnetized planets.

Simultaneous estimation of Ocean mesoscale and coherent internal tide Sea Surface Height signatures from the global Altimetry record

This study proposes an approach to estimate the Ocean Sea Surface Height signature of coherent internal tidesfrom 25 years of along-track altimetry record, with a single inversion over time, resolving both internal tide contributions andmesoscale eddy variability. The inversion is performed through reduced-order basis with conjugate gradient resolution. Theparticularity of this approach is to mitigate the potential aliasing effects between mesoscales and internal tide estimation fromthe uneven altimetry sampling (observing the sum of these components) by accounting of their statistics simultaneously, while other methods generally use a prior for mesoscales. The four major tidal components are considered (M2,K1,S2,O1) over theperiod 1992–2017 on a global configuration. From the solution, we use altimetry data after 2017 for an independent validation,to evaluate the benefits of the simultaneous inversion, and also to compare the skills with an existing model.

Emergence of border-ownership by large-scale consistency and long-range interactions: Neuro-computational model to reflect global configurations

The visual system performs remarkably well to perceive depth order of surfaces without stereo disparity, indicating the importance of figure-ground organization based on pictorial cues. To understand how figure-ground organization emerges, it is essential to investigate how the global configuration of an image is reflected. In the past, many neuro-computational models developed to reproduce figure-ground organization implemented algorithms to give a bias to convex areas. However, in certain conditions, a convex area can be perceived as a hole and a non-convex area as figural. This occurs when the surface properties of the convex area are consistent with the background and, hence, are grouped together in our perception. We argue that large-scale consistency of surface properties is reflected in the border-ownership computation. We developed a model, called DISC2, that first analyzes relationships between two border-ownership signals of all possible combinations in the image. It then enhances signals if they satisfy the following conditions: 1. the two signals fit to a convex configuration, and 2. the surface properties at the locations of the two signals are consistent. The strength of the enhancement decays with distance between the signals. The model gives extremely robust responses to various images with complexities both in shape and depth order. Furthermore, we developed an advanced version of the model ("augmented model") where the global computation above interacts with local computation of curvilinearity, which further enhanced the robust nature of the model. The results suggest the involvement of similar computational processes in the brain for figure-ground organization.

Cosmic hylomorphism

The primitive ontology approach to quantum mechanics seeks to account for quantum phenomena in terms of a distribution of matter in three-dimensional space (or four-dimensional spacetime) and a law of nature that describes its temporal development. This approach to explaining quantum phenomena is compatible with either a Humean or powerist account of laws. In this paper, I offer a powerist ontology in which the law is specified by Bohmian mechanics for a global configuration of particles. Unlike in other powerist ontologies, however, this law is not grounded in a structural power that is instantiated by the global configuration. Instead, I combine the primitive ontology approach with Aristotle’s doctrine of hylomorphism to create a new metaphysical model, in which the cosmos is a hylomorphic substance with an intrinsic power to choreograph the trajectories of the particles.

Discretely assembled mechanical metamaterials

Mechanical metamaterials offer exotic properties based on local control of cell geometry and their global configuration into structures and mechanisms. Historically, these have been made as continuous, monolithic structures with additive manufacturing, which affords high resolution and throughput, but is inherently limited by process and machine constraints. To address this issue, we present a construction system for mechanical metamaterials based on discrete assembly of a finite set of parts, which can be spatially composed for a range of properties such as rigidity, compliance, chirality, and auxetic behavior. This system achieves desired continuum properties through design of the parts such that global behavior is governed by local mechanisms. We describe the design methodology, production process, numerical modeling, and experimental characterization of metamaterial behaviors. This approach benefits from incremental assembly, which eliminates scale limitations, best-practice manufacturing for reliable, low-cost part production, and interchangeability through a consistent assembly process across part types.

(Re-)organisation of spatial configurations in visual working memory: The fate of objects rendered relevant or irrelevant by selective attention

People maintain object locations not as independent absolute positions but based on inter-object relations in the form of a spatial configuration in visual working memory (VWM). Initial evidence suggests that spatial configurations can be reorganised during maintenance; however, this mechanism is not well understood. We report three experiments investigating this reorganisation process. First, we found that directing spatial attention with a retro cue triggers a reorganisation of spatial configurations during maintenance (Experiment 1). Second, we investigated the role of contextual objects rendered either relevant or irrelevant through the retro cue by manipulating the locations of the context at retrieval both within a partial display (Experiment 2a) and a whole display (Experiment 2b). Whereas the similar impairment of memory performance by changing the relevant and global context suggests a complete reorganisation of spatial configurations in VWM, this interpretation was challenged by the observation of impaired memory performance with changes of the irrelevant objects in a whole display that retains the relevant locations. Thus, we suggest that reorganisation should be considered to be the formation of a partial configuration based on the objects rendered relevant by the retro cue in addition to the originally encoded global configuration, with both configurations affecting memory performance.

Periodic tilings and auxetic deployments

We investigate geometric characteristics of a specific planar periodic framework with three degrees of freedom. While several avatars of this structural design have been considered in materials science under the name of chiral or missing rib models, all previous studies have addressed only local properties and limited deployment scenarios. We describe the global configuration space of the framework and emphasize the geometric underpinnings of auxetic deformations. Analogous structures may be considered in arbitrary dimension.

Overview of the first year of the NEMO global 1/36° configuration (ORCA36) development

&lt;div&gt;Mercator Ocean International operates global high-resolution forecasting systems in the framework of the Copernicus Marine Environment Monitoring Service. The current system has a 1/12&amp;#176; resolution. In order to prepare the increase of its resolution, the development of a new global configuration has started in 2019, with a higher resolution (1/36&amp;#176;). This configuration is also expected in the H2020 IMMERSE project as a demonstrator for the HPC improvements developed in NEMO OGCM and in the H2020 ESIWACE2 project as a demonstrator for production runs at unprecedented resolution on pre-exascale supercomputers. We present here the first 0RCA36 configuration and the first results of a simulation performed on several months forced&lt;/div&gt;&lt;div&gt;by ERAinterim with NEMO 4. We compare it with its twin global &amp;#188;&amp;#176; and 1/12&amp;#176; configurations. We also present some results of NEMO 4/ORCA36 performances and scalability, performed by BSC on Mare Nostrum supercomputer.&lt;/div&gt;