2,499 research outputs found
Still standing, still here, still dancing.
A personal narrative is presented which explores the author's experiences on teaching-learning process and her insights on language, culture and learning
LRR Voices: Health & Safety for Unorganized, Immigrant Workers
Pam Tau Lee is Labor Coordinator at the Labor Occupational Health Program at the University of California, Berkeley, and serves on the boards of the National Toxic Campaign Fund, National People of Color Environmental Summit, and the Chinese Progressive Association, She recently returned from Slovakia where she collaborated with environmentalists and worker representatives in setting up a participatory approach to health and safety research. LRR asked Lee to comment on the crucial role labor can play in the area of health and safety for unorganized, immigrant workers
Role of multi-level states on quantum-dot emission in photonic-crystal cavities
Semiconductor quantum dots embedded in photonic-crystal nanostructures have
been the subject of intense study. In this context, quantum dots are often
considered to be simple two-level emitters, i.e., the complexities arising from
the internal finestructure are neglected. We show that due to the intricate
spatial variations of the electric field polarization found in photonic
crystal, the two orthogonal finestructure states of quantum dots in general
both couple significantly to a cavity mode, implying that the two-level
description is not sufficient. As a consequence the emission dynamics and
spectra, which are often recorded in experiments, are modified both in the
weak- and strong-coupling regimes. The proposed effects are found to be
significant for system parameters of current state-of-the-art photonic-crystal
cavities
Phase diagram of symmetric binary mixtures at equimolar and non-equimolar concentrations: a systematic investigation
We consider symmetric binary mixtures consisting of spherical particles with
equal diameters interacting via a hard-core plus attractive tail potential with
strengths epsilon_{ij}, i,j=1,2, such that epsilon_{11} = epsilon_{22} >
epsilon_{12}. The phase diagram of the system at all densities and
concentrations is investigated as a function of the unlike-to-like interaction
ratio delta = epsilon_{12}/epsilon_{11} by means of the hierarchical reference
theory (HRT). The results are related to those of previous investigations
performed at equimolar concentration, as well as to the topology of the
mean-field critical lines. As delta is increased in the interval 0 < delta < 1,
we find first a regime where the phase diagram at equal species concentration
displays a tricritical point, then one where both a tricritical and a
liquid-vapor critical point are present. We did not find any clear evidence of
the critical endpoint topology predicted by mean-field theory as delta
approaches 1, at least up to delta=0.8, which is the largest value of delta
investigated here. Particular attention was paid to the description of the
critical-plus-tricritical point regime in the whole density-concentration
plane. In this situation, the phase diagram shows, in a certain temperature
interval, a coexistence region that encloses an island of homogeneous,
one-phase fluid.Comment: 27 pages + 20 figure
Learning Semantic Representations for the Phrase Translation Model
This paper presents a novel semantic-based phrase translation model. A pair
of source and target phrases are projected into continuous-valued vector
representations in a low-dimensional latent semantic space, where their
translation score is computed by the distance between the pair in this new
space. The projection is performed by a multi-layer neural network whose
weights are learned on parallel training data. The learning is aimed to
directly optimize the quality of end-to-end machine translation results.
Experimental evaluation has been performed on two Europarl translation tasks,
English-French and German-English. The results show that the new semantic-based
phrase translation model significantly improves the performance of a
state-of-the-art phrase-based statistical machine translation sys-tem, leading
to a gain of 0.7-1.0 BLEU points
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