362 research outputs found
Holography of Wrapped M5-branes and Chern-Simons theory
We study three-dimensional superconformal field theories on wrapped
M5-branes. Applying the gauge/gravity duality and the recently proposed 3d-3d
relation, we deduce quantitative predictions for the perturbative free energy
of a Chern-Simons theory on hyperbolic 3-space. Remarkably, the perturbative
expansion is expected to terminate at two-loops in the large N limit. We check
the correspondence numerically in a number of examples, and confirm the N^3
scaling with precise coefficients.Comment: 5 pages, 2 figures. Some clarifications, references added, misprint
correcte
Holography of 3d-3d correspondence at Large N
We study the physics of multiple M5-branes compactified on a hyperbolic
3-manifold. On the one hand, it leads to the 3d-3d correspondence which maps an
superconformal field theory to a pure Chern-Simons theory on
the 3-manifold. On the other hand, it leads to a warped AdS geometry in
M-theory holographically dual to the superconformal field theory. Combining the
holographic duality and the 3d-3d correspondence, we propose a conjecture for
the large limit of the perturbative free energy of a Chern-Simons theory on
hyperbolic 3-manifold. The conjecture claims that the tree, one-loop and
two-loop terms all share the same scaling behavior and are proportional
to the volume of the 3-manifold, while the three-loop and higher terms are
suppressed at large . Under mild assumptions, we prove the tree and one-loop
parts of the conjecture. For the two-loop part, we test the conjecture
numerically in a number of examples and find precise agreement. We also confirm
the suppression of higher loop terms in a few examples.Comment: 37 pages, 7 figure
An Evaluation of Clouds and Radiation in a Large-Scale Atmospheric Model Using a Cloud Vertical Structure Classification
We revisit the concept of the cloud vertical structure (CVS) classes we have previously employed to classify the planet's cloudiness (Oreopoulos et al., 2017). The CVS classification reflects simple combinations of simultaneous cloud occurrence in the three standard layers traditionally used to separate low, middle, and high clouds and was applied to a dataset derived from active lidar and cloud radar observations. This classification is now introduced in an atmospheric global climate model, specifically a version of NASA's GEOS-5, in order to evaluate the realism of its cloudiness and of the radiative effects associated with the various CVS classes. Such classes can be defined in GEOS-5 thanks to a sub column cloud generator paired with the model's radiative transfer algorithm, and their associated radiative effects can be evaluated against observations. We find that the model produces 50% more clear skies than observations in relative terms and produces isolated high clouds that are slightly less frequent than in observations, but optically thicker, yielding excessive planetary and surface cooling. Low clouds are also brighter than in observations, but underestimates of the frequency of occurrence (by ~20% in relative terms) help restore radiative agreement with observations. Overall the model better reproduces the longwave radiative effects of the various CVS classes because cloud vertical location is substantially constrained in the CVS framework
A non-unitary bulk-boundary correspondence: Non-unitary Haagerup RCFTs from S-fold SCFTs
We introduce a novel class of two-dimensional non-unitary rational conformal
field theories (RCFTs) whose modular data are identical to the generalized
Haagerup-Izumi modular data. Via the bulk-boundary correspondence, they are
related to the three-dimensional non-unitary Haagerup topological field
theories, recently constructed by a topological twisting of three-dimensional
rank-zero superconformal field theories (SCFTs), called S-fold
SCFTs. We propose that, up to the overall factors, the half-indices of the
rank-zero SCFTs give the explicit Nahm representation of four conformal
characters of the RCFTs including the vacuum character. Using the theory of
Bantay-Gannon, we can successfully complete them into the full admissible
conformal characters of the RCFTs.Comment: 35 page
SME supply chain collaboration innovation using an online hub
노트 : Proceedings of the 8th International Conference on Innovation & Managemen
Random Parameter Negative Binomial Model of Signalized Intersections
Factors affecting accident frequencies at 72 signalized intersections in the Gyeonggi-Do (province) over a four-year period (2007~2010) were explored using the random parameters negative binomial model. The empirical results from the comparison with fixed parameters binomial model show that the random parameters model outperforms its fixed parameters counterpart and provides a fuller understanding of the factors which determine accident frequencies at signalized intersections. In addition, elasticity and marginal effect were estimated to gain more insight into the effects of one-percent and one-unit changes in the dependent variable from changes in the independent variables
Relational Self-Supervised Learning on Graphs
Over the past few years, graph representation learning (GRL) has been a
powerful strategy for analyzing graph-structured data. Recently, GRL methods
have shown promising results by adopting self-supervised learning methods
developed for learning representations of images. Despite their success,
existing GRL methods tend to overlook an inherent distinction between images
and graphs, i.e., images are assumed to be independently and identically
distributed, whereas graphs exhibit relational information among data
instances, i.e., nodes. To fully benefit from the relational information
inherent in the graph-structured data, we propose a novel GRL method, called
RGRL, that learns from the relational information generated from the graph
itself. RGRL learns node representations such that the relationship among nodes
is invariant to augmentations, i.e., augmentation-invariant relationship, which
allows the node representations to vary as long as the relationship among the
nodes is preserved. By considering the relationship among nodes in both global
and local perspectives, RGRL overcomes limitations of previous contrastive and
non-contrastive methods, and achieves the best of both worlds. Extensive
experiments on fourteen benchmark datasets over various downstream tasks
demonstrate the superiority of RGRL over state-of-the-art baselines. The source
code for RGRL is available at https://github.com/Namkyeong/RGRL.Comment: CIKM 202
New Insights About Cloud Vertical Structure from CloudSat and CALIPSO Observations
Active cloud observations from A-Trains CloudSat and CALIPSO satellites offer new opportunities to examine the vertical structure of hydrometeor layers. We use the 2B CLDCLASSLIDAR merged CloudSat-CALIPSO product to examine global aspects of hydrometeor vertical stratification. We group the data into major Cloud Vertical Structure (CVS) classes based on our interpretation of how clouds in three standard atmospheric layers overlap, and provide their global frequency of occurrence. We contrast CVS occurrences between daytime and nighttime, identify ocean and land differences, and examine their seasonal and geographical variations for the dominant CVS classes. In order to evaluate CVS role in the radiation budget, we estimate radiative effects and contributions of the various CVS classes at the solar and thermal infrared part of the spectrum. We also investigate the consistency between passive and active views of clouds by providing the CVS breakdowns of MODIS cloud regimes for spatiotemporally coincident MODIS-Aqua and CloudSat-CALIPSO daytime observations. This analysis is expanded for a more in-depth look at the most heterogeneous of the MODIS regimes, and ultimately confirms previous interpretations of the nature of cloud regimes that did not have the benefit of collocated active observations
Arctic Policy of the Republic of Korea
Korea has been aware of the humanitarian and national significance of the Arctic and Antarctic since before the millennium. On the one hand, Korea has strived in the field of scientific research by joining the Antarctic Treaty System. On the other hand, Korea has promoted various economic cooperation with the Arctic nations. Korea joined the Antarctic Treaty System in 1986, established the Antarctic King Sejong Station in 1988, established the Arctic Dasan Station in Ny-Ålesund, Norway in 2002, and joined the Svalbard Treaty in 2012. Furthermore, Korea has participated in summits with the Arctic nations since 2008. In 2012, President Lee, Myung-Bak visited Russia, Greenland, and Norway to promote cooperation over the Northern Sea Route, shipbuilding, and energy resources, among other things. Behind the government actions over Polar activities lie government policies and plans, such as the Basic Plan of Antarctic Research (2007-2011, 2012-2016), Measures for the Advancement of Polar Region Policy (2012), Comprehensive Arctic Plan (2013), and Korean Arctic Master Plan (2013). This article will focus on the background to Korea’s 2013 Basic Plan for Arctic Policy, and the remaining tasks that now lie before the Korean government
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