Peculiar mean velocity profiles within a porous bed of an open channel

Peer reviewedPublisher PD

Evaluation of AAFE apparatus to measure residual and transient convection in zero-gravity

An evaluation apparatus which photographs convective and diffusive flows in crystal growth experiments is presented. Results in the following catagories are reported: (1) Human factors; (2) Electrical and mechanical; (3) Optical performance; and (4) Thermal performance

Untangling perceptual memory: hysteresis and adaptation map into separate cortical networks

Perception is an active inferential process in which prior knowledge is combined with sensory input, the result of which determines the contents of awareness. Accordingly, previous experience is known to help the brain “decide” what to perceive. However, a critical aspect that has not been addressed is that previous experience can exert 2 opposing effects on perception: An attractive effect, sensitizing the brain to perceive the same again (hysteresis), or a repulsive effect, making it more likely to perceive something else (adaptation). We used functional magnetic resonance imaging and modeling to elucidate how the brain entertains these 2 opposing processes, and what determines the direction of such experience-dependent perceptual effects. We found that although affecting our perception concurrently, hysteresis and adaptation map into distinct cortical networks: a widespread network of higher-order visual and fronto-parietal areas was involved in perceptual stabilization, while adaptation was confined to early visual areas. This areal and hierarchical segregation may explain how the brain maintains the balance between exploiting redundancies and staying sensitive to new information. We provide a Bayesian model that accounts for the coexistence of hysteresis and adaptation by separating their causes into 2 distinct terms: Hysteresis alters the prior, whereas adaptation changes the sensory evidence (the likelihood function)

Einfach so drauflosexperimentieren geht nicht

In der Neuroökonomie werden bisweilen auch Gedanken manipuliert. Das weckt Abwehrreflexe. Der Neuroökonom Christian Ruff sieht aber wenig Missbrauchspotenzial

Transition metal dissolution and degradation in nmc811-graphite electrochemical cells

Nickel-rich lithium nickel-manganese-cobalt oxide cathodes, in particular Li(Ni0.8Mn0.1Co0.1)O2 (NMC811), are currently being commercialized as next generation cathode materials, due to their increased capacities compared to current materials. Unfortunately, the higher nickel content has been shown to accelerate cell degradation and a better understanding is needed to maximize cell lifetimes. NMC811/graphite cells were tested under stressed conditions (elevated temperature and cell voltages) to accelerate degradation focusing on transition metal (TM) dissolution from the cathode. Increasing the cell temperature, upper cut-off voltage (UCV) and number of cycles all accelerated capacity fade and diffraction studies showed that under stressed conditions, additional degradation mechanisms beyond lithium loss to the SEI are present. Significant TM dissolution and subsequent deposition on the graphite anode is seen, particularly at stressed conditions. The concentration of TMs in the electrolyte remained invariant with cycling conditions, presumably reflecting the limited solubility of these ions and emphasizing the role that TM deposition on the anode plays in continuing to drive dissolution. Significant deposits of metals from the cell casings and current collectors were also detected at all cycling conditions, indicating that corrosion and metal leaching can be as important as TM dissolution from the active material in some cell formats.We thank Ms. Jennifer Allen, Prof. Mary Ryan and Dr Daniel Abraham for helpful discussions. We thank Stephen Young and Nigel Howard for assistance with the ICP-OES measurements. This work is supported by the Faraday Institution under grant no. FIRG00

IMPACT OF INFORMATION MANAGEMENT DURING DESIGN & CONSTRUCTION ON DOWNSTREAM BIM-GIS INTEROPERABILITY FOR RAIL INFRASTRUCTURE

The need for efficient and sustainable infrastructure – always critical to a city – is further gaining momentum as urbanisation creates the challenge of sustainably designing, constructing and operating the built environment. The AECOO industry, directly responsible for addressing this challenge, has adopted the use of BIM and GIS to aid in this endeavour. Both BIM and GIS overlap with respect to capturing aspects of the built environment, but are not interoperable by nature. To ensure a consistent and structured way of managing the information produced within these environments, industry standards such as IFC are implemented. Research to date focuses on addressing the integration between BIM and GIS for buildings by delving into the IFC and CityGML interoperability, which has highlighted significant geometric and semantic barriers that in the stage of integration, cannot be easily manoeuvred. The purpose of this paper is to provide an insight regarding the information lifecycle during Design & Construction in the HS2 Rail Infrastructure project and investigate the impact of current information management processes – and in particular Standards such as IFC, – on BIM-GIS interoperability and lifecycle management of an asset. Results demonstrate the levels of mis mapping during the export to IFC which varies depending on the infrastructure asset type. Discussion shows that these can be addressed by the introduction of additional semantic property sets to facilitate downstream BIM-GIS interoperability for O & M, enabling scope for future work