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Multimedia delivery in the future internet
The term âNetworked Mediaâ implies that all kinds of media including text, image, 3D graphics, audio
and video are produced, distributed, shared, managed and consumed on-line through various networks,
like the Internet, Fiber, WiFi, WiMAX, GPRS, 3G and so on, in a convergent manner [1]. This white
paper is the contribution of the Media Delivery Platform (MDP) cluster and aims to cover the Networked
challenges of the Networked Media in the transition to the Future of the Internet.
Internet has evolved and changed the way we work and live. End users of the Internet have been confronted
with a bewildering range of media, services and applications and of technological innovations concerning
media formats, wireless networks, terminal types and capabilities. And there is little evidence that the pace
of this innovation is slowing. Today, over one billion of users access the Internet on regular basis, more
than 100 million users have downloaded at least one (multi)media file and over 47 millions of them do so
regularly, searching in more than 160 Exabytes1 of content. In the near future these numbers are expected
to exponentially rise. It is expected that the Internet content will be increased by at least a factor of 6, rising
to more than 990 Exabytes before 2012, fuelled mainly by the users themselves. Moreover, it is envisaged
that in a near- to mid-term future, the Internet will provide the means to share and distribute (new)
multimedia content and services with superior quality and striking flexibility, in a trusted and personalized
way, improving citizensâ quality of life, working conditions, edutainment and safety.
In this evolving environment, new transport protocols, new multimedia encoding schemes, cross-layer inthe
network adaptation, machine-to-machine communication (including RFIDs), rich 3D content as well as
community networks and the use of peer-to-peer (P2P) overlays are expected to generate new models of
interaction and cooperation, and be able to support enhanced perceived quality-of-experience (PQoE) and
innovative applications âon the moveâ, like virtual collaboration environments, personalised services/
media, virtual sport groups, on-line gaming, edutainment. In this context, the interaction with content
combined with interactive/multimedia search capabilities across distributed repositories, opportunistic P2P
networks and the dynamic adaptation to the characteristics of diverse mobile terminals are expected to
contribute towards such a vision.
Based on work that has taken place in a number of EC co-funded projects, in Framework Program 6 (FP6)
and Framework Program 7 (FP7), a group of experts and technology visionaries have voluntarily
contributed in this white paper aiming to describe the status, the state-of-the art, the challenges and the way
ahead in the area of Content Aware media delivery platforms
The Physics and Mass Assembly of distant galaxies with the E-ELT
One of the main science goal of the future European Extremely Large Telescope
will be to understand the mass assembly process in galaxies as a function of
cosmic time. To this aim, a multi-object, AO-assisted integral field
spectrograph will be required to map the physical and chemical properties of
very distant galaxies. In this paper, we examine the ability of such an
instrument to obtain spatially resolved spectroscopy of a large sample of
massive (0.1<Mstellar<5e11Mo) galaxies at 2<z<6, selected from future large
area optical-near IR surveys. We produced a set of about one thousand numerical
simulations of 3D observations using reasonable assumptions about the site,
telescope, and instrument, and about the physics of distant galaxies. These
data-cubes were analysed as real data to produce realistic kinematic
measurements of very distant galaxies. We then studied how sensible the
scientific goals are to the observational (i.e., site-, telescope-, and
instrument-related) and physical (i.e., galaxy-related) parameters. We
specifically investigated the impact of AO performance on the science goal. We
did not identify any breaking points with respect to the parameters (e.g., the
telescope diameter), with the exception of the telescope thermal background,
which strongly limits the performance in the highest (z>5) redshift bin. We
find that a survey of Ngal galaxies that fulfil the range of science goals can
be achieved with a ~90 nights program on the E-ELT, provided a multiplex
capability M Ngal/8.Comment: 21 pages, 13 figures, 7 tables. Accepted for publication in MNRA
Automatic Image Segmentation by Dynamic Region Merging
This paper addresses the automatic image segmentation problem in a region
merging style. With an initially over-segmented image, in which the many
regions (or super-pixels) with homogeneous color are detected, image
segmentation is performed by iteratively merging the regions according to a
statistical test. There are two essential issues in a region merging algorithm:
order of merging and the stopping criterion. In the proposed algorithm, these
two issues are solved by a novel predicate, which is defined by the sequential
probability ratio test (SPRT) and the maximum likelihood criterion. Starting
from an over-segmented image, neighboring regions are progressively merged if
there is an evidence for merging according to this predicate. We show that the
merging order follows the principle of dynamic programming. This formulates
image segmentation as an inference problem, where the final segmentation is
established based on the observed image. We also prove that the produced
segmentation satisfies certain global properties. In addition, a faster
algorithm is developed to accelerate the region merging process, which
maintains a nearest neighbor graph in each iteration. Experiments on real
natural images are conducted to demonstrate the performance of the proposed
dynamic region merging algorithm.Comment: 28 pages. This paper is under review in IEEE TI
Influence of Ground Rotations on the Seismic Response of Building Structures
Despite being studied for over four decades, seismic design codes still fail to incorporate ground rotations in analysis and design. The primary reason is the currently installed accelerometers' inability to measure ground rotation. In addition, installing sensors to measure ground rotations on a large scale is not feasible anytime soon. So, researchers have relied on indirect methods to derive rotational motions from translational records such as single station, multiple station procedures, and so on. However, these methods are unreliable during near-field events where the instruments can themselves rotate. This paper utilizes the application of high-performance computing (HPC) to extract ground rotations in light of these shortcomings. Due to recent advancements in HPC, the simulation of strong near-field events with high accuracy and high-frequency resolution is possible. This paper implements the newly developed Earthquake Simulation (EQSIM) fault-to-structure framework that uses an emerging GPU-based exascale computer platform. The simulation workflow consists of two steps. Initially, a 3D geophysical model representing a large domain of earth is developed, and the model is analyzed in SW4 fourth-order wave propagation code for two earthquake scenarios, Strike-slip and Reverse-thrust. Then, the ground motions extracted from the first step, including the rotational motion, are used to drive the engineering model of fixed-base and soil-structure interaction systems (SSI) through Domain Reduction Method (DRM). For this purpose, four canonical steel moment frame structures of 3-, 9-,20-, and 40-story are modeled in OpenSees. Finally, nonlinear time history analyses are performed to study the effect of ground rotation on the response of the considered structures. Results indicate that the ground rotations can significantly increase the buildings' inter-story drifts, producing additional amplification when SSI is included. The impact of ground rotation is dictated by the fundamental natural frequency of the building along with the frequency and phase content of input motions
A Hierarchical Representation Network for Accurate and Detailed Face Reconstruction from In-The-Wild Images
Limited by the nature of the low-dimensional representational capacity of
3DMM, most of the 3DMM-based face reconstruction (FR) methods fail to recover
high-frequency facial details, such as wrinkles, dimples, etc. Some attempt to
solve the problem by introducing detail maps or non-linear operations, however,
the results are still not vivid. To this end, we in this paper present a novel
hierarchical representation network (HRN) to achieve accurate and detailed face
reconstruction from a single image. Specifically, we implement the geometry
disentanglement and introduce the hierarchical representation to fulfill
detailed face modeling. Meanwhile, 3D priors of facial details are incorporated
to enhance the accuracy and authenticity of the reconstruction results. We also
propose a de-retouching module to achieve better decoupling of the geometry and
appearance. It is noteworthy that our framework can be extended to a multi-view
fashion by considering detail consistency of different views. Extensive
experiments on two single-view and two multi-view FR benchmarks demonstrate
that our method outperforms the existing methods in both reconstruction
accuracy and visual effects. Finally, we introduce a high-quality 3D face
dataset FaceHD-100 to boost the research of high-fidelity face reconstruction.
The project homepage is at https://younglbw.github.io/HRN-homepage/.Comment: Accepted by CVPR202
The Origin And Loss Of Periodic Patterning In The Turtle Shell
The origin of the turtle shell over 200 million years ago greatly modified the amniote body plan, and the morphological plasticity of the shell has promoted the adaptive radiation of turtles. The shell, comprising a dorsal carapace and a ventral plastron, is a layered structure formed by basal endochondral axial skeletal elements (ribs, vertebrae) and plates of bone, which are overlain by keratinous ectodermal scutes. Studies of turtle development have mostly focused on the bones of the shell; however, the genetic regulation of the epidermal scutes has not been investigated. Here, we show that scutes develop from an array of patterned placodes and that these placodes are absent from a soft-shelled turtle in which scutes were lost secondarily. Experimentally inhibiting Shh, Bmp or Fgf signaling results in the disruption of the placodal pattern. Finally, a computational model is used to show how two coupled reaction-diffusion systems reproduce both natural and abnormal variation in turtle scutes. Taken together, these placodal signaling centers are likely to represent developmental modules that are responsible for the evolution of scutes in turtles, and the regulation of these centers has allowed for the diversification of the turtle shell
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