15,251 research outputs found
Deformable face ensemble alignment with robust grouped-L1 anchors
Many methods exist at the moment for deformable face fitting. A drawback to nearly all these approaches is that they are (i) noisy in terms of landmark positions, and (ii) the noise is biased across frames (i.e. the misalignment is toward common directions across all frames). In this paper we propose a grouped -norm anchored method for simultaneously aligning an ensemble of deformable face images stemming from the same subject, given noisy heterogeneous landmark estimates. Impressive alignment performance improvement and refinement is obtained using very weak initialization as "anchors"
The dependence of the pairwise velocity dispersion on galaxy properties
(abridged) We present measurements of the pairwise velocity dispersion (PVD)
for different classes of galaxies in the Sloan Digital Sky Survey. For a sample
of about 200,000 galaxies, we study the dependence of the PVD on galaxy
properties such as luminosity, stellar mass (M_*), colour (g-r), 4000A break
strength (D4000), concentration index (C), and stellar surface mass density
(\mu_*). The luminosity dependence of the PVD is in good agreement with the
results of Jing & B\"orner (2004) for the 2dFGRS catalog. The value of
\sigma_{12} measured at k=1 h/Mpc decreases as a function of increasing galaxy
luminosity for galaxies fainter than L*, before increasing again for the most
luminous galaxies in our sample. Each of the galaxy subsamples selected
according to luminosity or stellar mass is divided into two further subsamples
according to colour, D4000, C and \mu_*. We find that galaxies with redder
colours and higher D4000, C, and \mu_* values have larger PVDs on all scales
and at all luminosities/stellar masses. The dependence of the PVD on parameters
related to recent star formation(colour, D4000) is stronger than on parameters
related to galaxy structure (C, \mu_*), especially on small scales and for
faint galaxies. The reddest galaxies and galaxies with high surface mass
densities and intermediate concentrations have the highest pairwise peculiar
velocities, i.e. these move in the strongest gravitational fields. We conclude
that the faint red population located in rich clusters is responsible for the
high PVD values that are measured for low-luminosity galaxies on small scales.Comment: 14 pages, 13 figures; reference updated and text slightly changed to
match the published version; data of measurements of power spectrum and PVD
available at http://www.mpa-garching.mpg.de/~leech/papers/clustering
TrIMS: Transparent and Isolated Model Sharing for Low Latency Deep LearningInference in Function as a Service Environments
Deep neural networks (DNNs) have become core computation components within
low latency Function as a Service (FaaS) prediction pipelines: including image
recognition, object detection, natural language processing, speech synthesis,
and personalized recommendation pipelines. Cloud computing, as the de-facto
backbone of modern computing infrastructure for both enterprise and consumer
applications, has to be able to handle user-defined pipelines of diverse DNN
inference workloads while maintaining isolation and latency guarantees, and
minimizing resource waste. The current solution for guaranteeing isolation
within FaaS is suboptimal -- suffering from "cold start" latency. A major cause
of such inefficiency is the need to move large amount of model data within and
across servers. We propose TrIMS as a novel solution to address these issues.
Our proposed solution consists of a persistent model store across the GPU, CPU,
local storage, and cloud storage hierarchy, an efficient resource management
layer that provides isolation, and a succinct set of application APIs and
container technologies for easy and transparent integration with FaaS, Deep
Learning (DL) frameworks, and user code. We demonstrate our solution by
interfacing TrIMS with the Apache MXNet framework and demonstrate up to 24x
speedup in latency for image classification models and up to 210x speedup for
large models. We achieve up to 8x system throughput improvement.Comment: In Proceedings CLOUD 201
MULTIPLE TIER LOW OVERHEAD MEMORY LEAK DETECTOR
A memory leak detector system can be used to detect memory leaks, which is when a computer program fails to release unneeded memory allocations, in a computer that executes multiple programs. The system utilizes a multi tier methodology to detect memory leaks. In a first tier, the system collects a histogram representing allocation counts for different allocation sizes of memory at the computer. If the system detects an above-a-threshold increase in the number of allocations for one or more of the allocation sizes, the system marks the one or more allocation sizes as suspected leaks and proceeds to a second tier of the multiple tier method. In the second tier, the system collects a histogram based on call stacks that led to each above-a-threshold increase in allocation sizes detected in the first tier. The system marks the call stacks with an above-a-threshold increase in call stack traces as prospective leaks and proceeds to a third tier of the multiple tier leak detection method. In the third tier, the system records the allocation times of each memory allocation that fits the suspected leak profile, including leak sizes found in the first tier and call stacks found in the second tier. If the oldest allocations are not being freed and persist over a period of time, then the system marks the allocation(s), the allocation size(s), and the originating call stack(s) as a probable memory leak
Structured Meta-Mirrors for Beam Spatial Filtering
The work presents optical spatial filtering in reflection based on translationally invariant meta-mirrors. The meta-structure is generated by a thin grating presenting a transverse modulation of the refraction index on the sub-micron scale located in front of a mirror. We analyze the angular spectrum of the reflected waves for different types of structured meta-mirrors as well as the filtering effects of these meta-structures in reflected beams. The comparison between FDTD simulations of full Maxwell equations and different approximated models allows to determine the filtering contribution from the structured cavity and from Mie resonances associated to elements generating the grating.Peer ReviewedPostprint (author's final draft
Distribution logistics of online fashion retail business in China: A case study of VANCL
The rapid development of information technologies brings more convenience to people. Information technologies, especially the Internet, not only save time for consumers and companies but also provide them with more channels and opportunities for interaction and conducting transactions. One business revolution brought by Internet is online shopping â shopping and buying products in online stores or websites. Nowadays, online shopping has become a new consuming model for consumers both in China and around the world. This paper analyses online shopping for fashion in China and investigates the impact of online shopping on logistics industry using the case of âVANCLâ
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