160 research outputs found
Hippocampal place cells encode global location but not connectivity in a complex space
Flexible navigation relies on a cognitive map of space, thought to be implemented by hippocampal place cells: neurons that exhibit location-specific firing. In connected environments, optimal navigation requires keeping track of one’s location and of the available connections between subspaces. We examined whether the dorsal CA1 place cells of rats encode environmental connectivity in four geometrically identical boxes arranged in a square. Rats moved between boxes by pushing saloon-type doors that could be locked in one or both directions. Although rats demonstrated knowledge of environmental connectivity, their place cells did not respond to connectivity changes, nor did they represent doorways differently from other locations. Place cells coded location in a global reference frame, with a different map for each box and minimal repetitive fields despite the repetitive geometry. These results suggest that CA1 place cells provide a spatial map that does not explicitly include connectivity
An Approach to Conceptual and Embodiment Design within a New Product Development Lifecycle Framework
[EN] The design of new innovative products is the result of an accurate and precise management of knowledge sources all over its life cycle, such as technology, market, competitors and suppliers. The work contributes with a framework that shows how the knowledge sources influence in the state-of-the-art and market needs so that they become opportunities for innovating products addressing the whole product life cycle. It provides a systematic path from the early generation of
ideas to the production of a new product proposal. Through a deep analysis of previous research works of new product innovation life cycle development frameworks and linking it with knowledge management, strategic planning and
scorecards, we came out with a structured contribution. The result considers the concurrent activities and its relationships all the way through the product life cycle that can help in creativity and innovation, combined with a process management
proposal. Managing the sources of knowledge in highly dynamic markets and technologies is one of the major difficulties involved in innovative products design and development. The emerging knowledge from external sources is confronted
with organisation internal knowledge and experience in order to achieve the first product correct.This work was supported by the Spanish Government and the Universitat Jaume I of Castellon (Spain) through research [project number P11B2009-37], entitled 'Methodologies for Implementing Product lifecycle management tools for mechanical Small and Medium Enterprises'.Vila, C.; Albinana, JC. (2016). An Approach to Conceptual and Embodiment Design within a New Product Development Lifecycle Framework. International Journal of Production Research. 54(10):2856-2874. https://doi.org/10.1080/00207543.2015.1110632S28562874541
Investigation into current industrial practices relating to product lifecycle management in a multi-national manufacturing company
Product Lifecycle Management (PLM) systems have gained growing acceptance for managing all information relating to products throughout their full lifecycle, from idea conceptualisation through operations to servicing and disposal. This paper, through an in-depth exploratory study into a leading power generation manufacturing organisation, presents current PLM issues experienced by manufacturing companies, exploring three separate topics: 1) PLM, 2) Knowledge Management and Lessons Learnt and 3) Product Servicing and Maintenance. Following a review of published literature, results of the investigation are presented, analysing the responses of 17 employees interviewed. With respect to Product Development, it was found that information traceability is time consuming and change management requests take too long to complete. Results relating to knowledge management indicate that the Company operates a ‘who you know’ culture, but do aim to capture lessons learned on the manufacturing shop floor and assembly lines. Therefore, a prototype design is proposed to integrate the capturing of lessons learnt within the existing PLM system
TOI-858 B b: A hot Jupiter on a polar orbit in a loose binary
We report the discovery of a hot Jupiter on a 3.28-day orbit around a 1.08
M G0 star that is the secondary component in a loose binary system.
Based on follow-up radial velocity observations of TOI-858 B with CORALIE on
the Swiss 1.2 m telescope and CHIRON on the 1.5 m telescope at the Cerro Tololo
Inter-American Observatory (CTIO), we measured the planet mass to be M . Two transits were further observed with CORALIE to determine
the alignment of TOI-858 B b with respect to its host star. Analysis of the
Rossiter-McLaughlin signal from the planet shows that the sky-projected
obliquity is . Numerical simulations show that the
neighbour star TOI-858 A is too distant to have trapped the planet in a
Kozai-Lidov resonance, suggesting a different dynamical evolution or a
primordial origin to explain this misalignment. The 1.15 Msun primary F9 star
of the system (TYC 8501-01597-1, at ~11") was also observed with CORALIE
in order to provide upper limits for the presence of a planetary companion
orbiting that star.Comment: Accepted for publication in A&
TOI 694b and TIC 220568520b: Two Low-mass Companions near the Hydrogen-burning Mass Limit Orbiting Sun-like Stars
We report the discovery of TOI 694 b and TIC 220568520 b, two low-mass stellar companions in eccentric orbits around metal-rich Sun-like stars, first detected by the Transiting Exoplanet Survey Satellite (TESS). TOI 694 b has an orbital period of 48.05131 +- 0.00019 days and eccentricity of 0.51946 +- 0.00081, and we derive a mass of 89.0 +- 5.3 MJup (0.0849 +- 0.0051 M☉) and radius of 1.111 +- 0.017 RJup (0.1142 +- 0.0017 R☉). TIC 220568520 b has an orbital period of 18.55769 +- 0.00039 days and eccentricity of 0.0964 +- 0.0032, and we derive a mass of 107.2 +- 5.2 MJup (0.1023 +- 0.0050 M☉) and radius of 1.248 +- 0.018 RJup (0.1282 +- 0.0019 R☉). Both binary companions lie close to and above the hydrogen-burning mass threshold that separates brown dwarfs and the lowest-mass stars, with TOI 694 b being 2σ above the canonical mass threshold of 0.075 M☉. The relatively long periods of the systems mean that the magnetic fields of the low-mass companions are not expected to inhibit convection and inflate the radius, which according to one leading theory is common in similar objects residing in short-period tidally synchronized binary systems. Indeed we do not find radius inflation for these two objects when compared to theoretical isochrones. These two new objects add to the short but growing list of low-mass stars with well-measured masses and radii, and highlight the potential of the TESS mission for detecting such rare objects orbiting bright stars.M.N.G. acknowledges
support from MIT’s Kavli Institute as a Torres postdoctoral
fellow. L.A.dS. is supported by funding from the European
Research Council (ERC) under the European Unionʼs Horizon
2020 research and innovation program (project FOUR ACES;
grant agreement No 724427). A.J. acknowledges support from
FONDECYT project 1171208 and by the Ministry for the
Economy, Development, and Tourism’s Programa Iniciativa
Científica Milenio through grant IC 120009, awarded to the
Millennium Institute of Astrophysics (MAS)
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