1,883 research outputs found
Multi-microjoule GaSe-based mid-infrared optical parametric amplifier with an ultra-broad idler spectrum covering 4.2-16 {\mu}m
We report a multi-microjoule, ultra-broadband mid-infrared optical parametric
amplifier based on a GaSe nonlinear crystal pumped at ~2 {\mu}m. The generated
idler pulse has a flat spectrum spanning from 4.5 to 13.3 {\mu}m at -3 dB and
4.2 to 16 {\mu}m in the full spectral range, with a central wavelength of 8.8
{\mu}m. The proposed scheme supports a sub-cycle Fourier-transform-limited
pulse width. A (2+1)-dimensional numerical simulation is employed to reproduce
the obtained idler spectrum. To our best knowledge, this is the broadest -3 dB
spectrum ever obtained by optical parametric amplifiers in this spectral
region. The idler pulse energy is ~3.4 {\mu}J with a conversion efficiency of
~2% from the ~2 {\mu}m pump to the idler pulse.Comment: 5 pages, 5 figure
Bid Optimization by Multivariable Control in Display Advertising
Real-Time Bidding (RTB) is an important paradigm in display advertising,
where advertisers utilize extended information and algorithms served by Demand
Side Platforms (DSPs) to improve advertising performance. A common problem for
DSPs is to help advertisers gain as much value as possible with budget
constraints. However, advertisers would routinely add certain key performance
indicator (KPI) constraints that the advertising campaign must meet due to
practical reasons. In this paper, we study the common case where advertisers
aim to maximize the quantity of conversions, and set cost-per-click (CPC) as a
KPI constraint. We convert such a problem into a linear programming problem and
leverage the primal-dual method to derive the optimal bidding strategy. To
address the applicability issue, we propose a feedback control-based solution
and devise the multivariable control system. The empirical study based on
real-word data from Taobao.com verifies the effectiveness and superiority of
our approach compared with the state of the art in the industry practices
A representation basis for the quantum integrable spin chain associated with the su(3) algebra
An orthogonal basis of the Hilbert space for the quantum spin chain
associated with the su(3) algebra is introduced. Such kind of basis could be
treated as a nested generalization of separation of variables (SoV) basis for
high-rank quantum integrable models. It is found that all the monodromy-matrix
elements acting on a basis vector take simple forms. With the help of the
basis, we construct eigenstates of the su(3) inhomogeneous spin torus (the
trigonometric su(3) spin chain with antiperiodic boundary condition) from its
spectrum obtained via the off-diagonal Bethe Ansatz (ODBA). Based on small
sites (i.e. N=2) check, it is conjectured that the homogeneous limit of the
eigenstates exists, which gives rise to the corresponding eigenstates of the
homogenous model.Comment: 24 pages, no figure, published versio
Exact solution of the Izergin-Korepin model with general non-diagonal boundary terms
The Izergin-Korepin model with general non-diagonal boundary terms, a typical
integrable model beyond A-type and without U(1)-symmetry, is studied via the
off-diagonal Bethe ansatz method. Based on some intrinsic properties of the
R-matrix and the K-matrices, certain operator product identities of the
transfer matrix are obtained at some special points of the spectral parameter.
These identities and the asymptotic behaviors of the transfer matrix together
allow us to construct the inhomogeneous T-Q relation and the associated Bethe
ansatz equations. In the diagonal boundary limit, the reduced results coincide
exactly with those obtained via other methods.Comment: 24 pages, published versio
GRAPHIE: Graph Based Histology Image Explorer
BACKGROUND: Histology images comprise one of the important sources of knowledge for phenotyping studies in systems biology. However, the annotation and analyses of histological data have remained a manual, subjective and relatively low-throughput process. RESULTS: We introduce Graph based Histology Image Explorer (GRAPHIE)-a visual analytics tool to explore, annotate and discover potential relationships in histology image collections within a biologically relevant context. The design of GRAPHIE is guided by domain experts' requirements and well-known InfoVis mantras. By representing each image with informative features and then subsequently visualizing the image collection with a graph, GRAPHIE allows users to effectively explore the image collection. The features were designed to capture localized morphological properties in the given tissue specimen. More importantly, users can perform feature selection in an interactive way to improve the visualization of the image collection and the overall annotation process. Finally, the annotation allows for a better prospective examination of datasets as demonstrated in the users study. Thus, our design of GRAPHIE allows for the users to navigate and explore large collections of histology image datasets. CONCLUSIONS: We demonstrated the usefulness of our visual analytics approach through two case studies. Both of the cases showed efficient annotation and analysis of histology image collection
iGPSe: A Visual Analytic System for Integrative Genomic Based Cancer Patient Stratification
Background: Cancers are highly heterogeneous with different subtypes. These
subtypes often possess different genetic variants, present different
pathological phenotypes, and most importantly, show various clinical outcomes
such as varied prognosis and response to treatment and likelihood for
recurrence and metastasis. Recently, integrative genomics (or panomics)
approaches are often adopted with the goal of combining multiple types of omics
data to identify integrative biomarkers for stratification of patients into
groups with different clinical outcomes. Results: In this paper we present a
visual analytic system called Interactive Genomics Patient Stratification
explorer (iGPSe) which significantly reduces the computing burden for
biomedical researchers in the process of exploring complicated integrative
genomics data. Our system integrates unsupervised clustering with graph and
parallel sets visualization and allows direct comparison of clinical outcomes
via survival analysis. Using a breast cancer dataset obtained from the The
Cancer Genome Atlas (TCGA) project, we are able to quickly explore different
combinations of gene expression (mRNA) and microRNA features and identify
potential combined markers for survival prediction. Conclusions: Visualization
plays an important role in the process of stratifying given population
patients. Visual tools allowed for the selection of possibly features across
various datasets for the given patient population. We essentially made a case
for visualization for a very important problem in translational informatics.Comment: BioVis 2014 conferenc
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