1,288 research outputs found
A Statistical Meta-Analysis of the Design Components of New Urbanism on Housing Prices
The principles of New Urbanism such as increased density, mixed land uses and street connectivity are often recommended in response to the typical conditions of suburban developments. Much current empirical research has begun to test whether these principles can increase property values. The findings of these empirical studies have, however, been quite inconsistent. This research attempts to quantitatively synthesize these conflicting findings through a statistical meta-analysis. This study found that a lower density, decreased street connectivity and a closer proximity to a transit stop contributed to increased housing premiums, while mixed land uses were not shown to always do so
Shock wave propagation in vibrofluidized granular materials
Shock wave formation and propagation in two-dimensional granular materials
under vertical vibration are studied by digital high speed photography. The
steepen density and temperature wave fronts form near the plate as granular
layer collides with vibrating plate and propagate upward through the layer. The
temperature front is always in the transition region between the upward and
downward granular flows. The effects of driving parameters and particle number
on the shock are also explored.Comment: 9 pages, 4 figures, submitted to PR
A lost decade for third-wave democracies?
By comparing results based on expert and popular surveys, this article finds that popular support for democracy was dwindling even in the decade before expert surveys (such as Freedom in the World and V-Dem) began to show the reality of democratic retreat. Decreasing support for democracy is tied to low satisfaction with how democracy works in practice, and it contributes to the rise of populist leaders who concentrate power in the executive branch. These phenomena reflect the waning capacity of the state to improve governance across all countries. As a result, democracy is likely to face another lackluster decade if both structural and institutional problems are left unsolved
Formation and transportation of sand-heap in an inclined and vertically vibrated container
We report the experimental findings of formation and motion of heap in
granular materials in an inclined and vertically vibrated container. We show
experimentally how the transport velocity of heap up container is related to
the driving acceleration as well as the driving frequency of exciter. An
analogous experiment was performed with a heap-shaped Plexiglas block. We
propose that cohesion force resulted from pressure gradient in ambient gas
plays a crucial role in enhancing and maintaining a heap, and ratchet effect
causes the movement of the heap. An equation which governs the transport
velocity of the heap is presented.Comment: 9 pages, 5 figures, submitted to PR
Controlling magnetization reversal in Co/Pt nanostructures with perpendicular anisotropy
We demonstrate a simple method to tailor the magnetization reversal
mechanisms of Co/Pt multilayers by depositing them onto large area nanoporous
anodized alumina (AAO) with various aspect ratios, A = pore depth/diameter.
Magnetization reversal of composite (Co/Pt)/AAO films with large A is governed
by strong domain-wall pinning which gradually transforms into a
rotation-dominated reversal for samples with smaller A, as investigated by a
first-order reversal curve method in conjunction with analysis of the angular
dependent switching fields. The change of the magnetization reversal mode is
attributed to topographical changes induced by the aspect ratio of the AAO
templates.Comment: 12 pages, 3 figure
Higher-order Topological Phases of Magnons in van der Waals Honeycomb Ferromagnets
We theoretically propose a second-order topological magnon insulator by
stacking the van der Waals honeycomb ferromagnets with antiferromagnetic
interlayer coupling. The system exhibits Z topological phase, protected
by pseudo-time-reversal symmetry (PTRS). An easy-plane anisotropy term breaks
PTRS and destroys the topological phase. Nevertheless, it respects a magnetic
two-fold rotational symmetry which protects a second-order topological phase
with corner modes in bilayer and hinge modes along stacking direction.
Moreover, an introduced staggered interlayer coupling establishes a
ZZ topology, giving rise to gapped topological surface modes
carrying non-zero Chern numbers. Consequently, chiral hinge modes propagate
along the horizontal hinges in a cuboid geometry and are robust against
disorders. Our work bridges the higher-order topology and magnons in van der
Waals platforms, and could be used for constructing topological magnonic
devices
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