Mechanical sequential counting with liquid marbles

© 2018, Springer International Publishing AG, part of Springer Nature. Here we demonstrate the first working example of a liquid marble-operated sequential binary counting device. We have designed a lightweight gate that can be actuated by the low mass and momentum of a liquid marble. By linking a number of these gates in series, we are able to digitally count up to binary 1111 (upper limit only by our requirements). Using liquid marbles in such a system opens up new avenues of research and design, by way of modifying the coating and/or core of the liquid marbles, and thereby giving extra dimensions for calculation (e.g. a calculation that takes into consideration the progress of a chemical reaction inside a liquid marble). In addition, the new gate design has multiple uses in liquid marble rerouting

Experimental and computational investigation of flow of pebbles in a pebble bed nuclear reactor

The Pebble Bed Reactor (PBR) is a 4th generation nuclear reactor which is conceptually similar to moving bed reactors used in the chemical and petrochemical industries. In a PBR core, nuclear fuel in the form of pebbles moves slowly under the influence of gravity. Due to the dynamic nature of the core, a thorough understanding about slow and dense granular flow of pebbles is required from both a reactor safety and performance evaluation point of view. In this dissertation, a new integrated experimental and computational study of granular flow in a PBR has been performed. Continuous pebble re-circulation experimental set-up, mimicking flow of pebbles in a PBR, is designed and developed. Experimental investigation of the flow of pebbles in a mimicked test reactor was carried out for the first time using non-invasive radioactive particle tracking (RPT) and residence time distribution (RTD) techniques to measure the pebble trajectory, velocity, overall/zonal residence times, flow patterns etc. The tracer trajectory length and overall/zonal residence time is found to increase with change in pebble\u27s initial seeding position from the center towards the wall of the test reactor. Overall and zonal average velocities of pebbles are found to decrease from the center towards the wall. Discrete element method (DEM) based simulations of test reactor geometry were also carried out using commercial code EDEM and simulation results were validated using the obtained benchmark experimental data. In addition, EDEM based parametric sensitivity study of interaction properties was carried out which suggests that static friction characteristics play an important role from a packed/pebble beds structural characterization point of view. To make the RPT technique viable for practical applications and to enhance its accuracy, a novel and dynamic technique for RPT calibration was designed and developed. Preliminary feasibility results suggest that it can be implemented as a non-invasive and dynamic calibration methodology for RPT technique which will enable its industrial applications. --Abstract, page iii

A suggested outline for a course of study in arithmetic for the first grade in Burma

Thesis (Ed.M.)--Boston Universit

Mentalizing Objects

We have a mentalistic view of objects. This is due to the interdependence of folk psychology and folk physics, where these are interconnected by what I call Teleological Commingling. When considering events that don’t involve agents, we naturally default to tracking intentions, goal-directed processes, despite the fact that agents aren’t involved. We have a deep-seated intentionality bias which is the result of the pervasive detection of agency cues, such as order or non-randomness. And this gives rise to the Agentive Worldview: we view nature as a whole as being infused with agency and purpose. Teleological Commingling and the Agentive Worldview it gives rise to are at the core of our conception of objects. I maintain that the ordinary view of material objects is rooted in an implicit, false theory. It should be given no weight in metaphysical debates about the nature of material objects. And this problematizes the central methodological assumption that metaphysical theories of material objects should be beholden to common sense

Rapid precipitation of magnesite micro-crystals from Mg(OH)2-H2O-CO2 slurry enhanced by NaOH and a heat-ageing step (from 20 to 90°C)

International audienceThis study proposes a simple and novel synthesis route for rhombohedral single crystals (90°C) and its synthesis requires several days or weeks depending on experimental conditions. For this reason, industrial-scale magnesite production has been limited. The proposed magnesite synthesis method, requiring only 48h and moderate temperature, could easily be extrapolated on an industrial scale. Moreover, a simple and novel synthesis route for the production of fine platy particles of hydromagnesite is reported, with synthesis requiring only 5h. Based on their chemical compositions and textural properties, there are potential applications for both minerals, for example as a mineral filler and/or as a flame-retardant

Intrinsic Geometrical Constraints of Spontaneously Excited Leidenfrost Drops

A liquid drop placed on a heated surface above the Leidenfrost temperature will levitate on a vapor cushion. The static shape of these non-wetting Leidenfrost drops is that of a flattened sphere, reflecting the balance between gravitational, surface tension and lubrication pressures. In this thesis, we study Leidenfrost drops on curved substrates where we observe spontaneous star-shaped surface oscillations of characteristic frequency and mode number. Experiments are conducted using six different liquids and the temporal response of the observed modes n = 2 – 13 is analyzed to dene the oscillation spectrum. We observe that large drops oscillate with a constant frequency, while small drop frequencies are strongly dependent upon liquid volume. A simple mathematical model is developed using a hydrodynamic stability analysis and shows reasonable agreement with our large experimental data set. Scaling arguments are used to collapse the data which allows generalized statements to be made regarding the physics governing star oscillations. In addition, we observe more complex dynamics such as mode doubling where two distinct modes are simultaneously excited at different frequencies and modal dominance where one mode persists over large ranges of parameter space previously thought to be occupied by another mode. Lastly, we conclude by offering some qualitative observations of Leidenfrost shape instabilities in other complex substrate geometries

A guide for teaching arithmetic in the elementary grades.

Thesis (Ed.M.)--Boston Universit

Utilizing A Quality Circle Team Approach To Design A Curriculum Resource Guide For The TK-1 Teacher

The author designed a Curriculum Resource Guide for the TK-1 teacher using a Quality Circle Team approach. The intent of this practicum was to provide the TI-1 teachers with a Resource Guide to aid in curriculum planning for the TK-1 developmental placement class. After reviewing results of surveys given to TK-1 teachers in Kent County, a guide was designed based on the results and research of specialists in the field of developmental placement. At the conclusion of the project each member of the Quality Circle Team was asked to rate the final product using a criterion referenced evaluation form which addressed each of the ten components. Criteria for each section was (a) Is the message clear? (b) Is it educationally sound? (c) Does it fit the TK-1 grade level? Participants could respond yes, no, or unclear. Every item showed a unanimous yes response for each component. The achievement of leadership effectiveness was rated high. Recommendations were made to the PREP Office that the Curriculum Resource Guide should be considered for county adoption to be used by all TK-1 teachers and as a reference for other educators and parents. Appendices include surveys, evaluations, and the Curriculum Resource Guide for the TK-1 Teacher