46,613 research outputs found
Property Tax and Urban Sprawl: Theory and Implications for U.S. Cities
This article attempts a formal analysis of the connection between property tax and urban sprawl in U.S. cities. We develop a theoretical model that includes households (who are also landlords) and land developers in a regional land market. We then test the model empirically based on a national sample of urbanized areas. The results we obtained from both theoretical and empirical analyses indicate that increasing property tax rates reduces the size of urbanized areas.Urban Sprawl; Full Closed City; Urban Economics; Property Tax; Instrumental Variables
dualities
We study a class of two-dimensional quiver gauge theories
that flow to superconformal field theories. We find dualities for the
superconformal field theories similar to the 4d theories of class
, labelled by a Riemann surface . The dual descriptions
arise from various pair-of-pants decompositions, that involves an analog of the
theory. Especially, we find the superconformal index of such theories can
be written in terms of a topological field theory on . We interpret
this class of SCFTs as the ones coming from compactifying 6d
theory on Comment: 41 pages, 12 figure
Learning Deep Representations of Appearance and Motion for Anomalous Event Detection
We present a novel unsupervised deep learning framework for anomalous event
detection in complex video scenes. While most existing works merely use
hand-crafted appearance and motion features, we propose Appearance and Motion
DeepNet (AMDN) which utilizes deep neural networks to automatically learn
feature representations. To exploit the complementary information of both
appearance and motion patterns, we introduce a novel double fusion framework,
combining both the benefits of traditional early fusion and late fusion
strategies. Specifically, stacked denoising autoencoders are proposed to
separately learn both appearance and motion features as well as a joint
representation (early fusion). Based on the learned representations, multiple
one-class SVM models are used to predict the anomaly scores of each input,
which are then integrated with a late fusion strategy for final anomaly
detection. We evaluate the proposed method on two publicly available video
surveillance datasets, showing competitive performance with respect to state of
the art approaches.Comment: Oral paper in BMVC 201
Vertex operator algebras of Argyres-Douglas theories from M5-branes
We study aspects of the vertex operator algebra (VOA) corresponding to
Argyres-Douglas (AD) theories engineered using the 6d N=(2, 0) theory of type
on a punctured sphere. We denote the AD theories as , where
and represent an irregular and a regular singularity respectively.
We restrict to the `minimal' case where has no associated mass
parameters, and the theory does not admit any exactly marginal deformations.
The VOA corresponding to the AD theory is conjectured to be the W-algebra
, where with being
the dual Coxeter number of . We verify this conjecture by showing that the
Schur index of the AD theory is identical to the vacuum character of the
corresponding VOA, and the Hall-Littlewood index computes the Hilbert series of
the Higgs branch. We also find that the Schur and Hall-Littlewood index for the
AD theory can be written in a simple closed form for . We also test the
conjecture that the associated variety of such VOA is identical to the Higgs
branch. The M5-brane construction of these theories and the corresponding TQFT
structure of the index play a crucial role in our computations.Comment: 35 pages, 1 figure, v2: minor corrections, referenced adde
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