259 research outputs found
The relationship of word error rate to document ranking
This paper describes two experiments that examine the relationship of Word Error Rate (WER) of retrieved
spoken documents returned by a spoken document retrieval system. Previous work has demonstrated that
recognition errors do not significantly affect retrieval effectiveness but whether they will adversely affect
relevance judgement remains unclear. A user-based experiment measuring ability to judge relevance from
the recognised text presented in a retrieved result list was conducted. The results indicated that users were
capable of judging relevance accurately despite transcription errors. This lead an examination of the
relationship of WER in retrieved audio documents to their rank position when retrieved for a particular
query. Here it was shown that WER was somewhat lower for top ranked documents than it was for
documents retrieved further down the ranking, thereby indicating a possible explanation for the success of
the user experiment
Photodegradation of secondary organic aerosol generated from limonene oxidation by ozone studied with chemical ionization mass spectrometry
Photodegradation of secondary organic aerosol (SOA) prepared by ozone-initiated oxidation of D-limonene is studied with an action spectroscopy approach, which relies on detection of volatile photoproducts with chemical ionization mass-spectrometry as a function of the UV irradiation wavelength. Efficient photodegradation is observed for a broad range of ozone (0.1–300 ppm) and D-limonene (0.02–3 ppm) concentrations used in the preparation of SOA. The observed photoproducts are dominated by oxygenated C1-C3 compounds such as methanol, formic acid, acetaldehyde, acetic acid, and acetone. The irradiation wavelength dependence of the combined yield of the photoproducts closely tracks the absorption spectrum of the SOA material suggesting that photodegradation is not limited to the UV wavelengths. Kinetic simulations suggest that RO<sub>2</sub>+HO<sub>2</sub>/RO<sub>2</sub> reactions represent the dominant route to photochemically active carbonyl and peroxide species in the limonene SOA prepared in these experiments. Similar photodegradation processes are likely to occur in realistic SOA produced by OH- or O<sub>3</sub>-initiated oxidation of biogenic volatile organic compounds in clean air
Person Re-identification with Deep Similarity-Guided Graph Neural Network
The person re-identification task requires to robustly estimate visual
similarities between person images. However, existing person re-identification
models mostly estimate the similarities of different image pairs of probe and
gallery images independently while ignores the relationship information between
different probe-gallery pairs. As a result, the similarity estimation of some
hard samples might not be accurate. In this paper, we propose a novel deep
learning framework, named Similarity-Guided Graph Neural Network (SGGNN) to
overcome such limitations. Given a probe image and several gallery images,
SGGNN creates a graph to represent the pairwise relationships between
probe-gallery pairs (nodes) and utilizes such relationships to update the
probe-gallery relation features in an end-to-end manner. Accurate similarity
estimation can be achieved by using such updated probe-gallery relation
features for prediction. The input features for nodes on the graph are the
relation features of different probe-gallery image pairs. The probe-gallery
relation feature updating is then performed by the messages passing in SGGNN,
which takes other nodes' information into account for similarity estimation.
Different from conventional GNN approaches, SGGNN learns the edge weights with
rich labels of gallery instance pairs directly, which provides relation fusion
more precise information. The effectiveness of our proposed method is validated
on three public person re-identification datasets.Comment: accepted to ECCV 201
Spin-based quantum information processing with semiconductor quantum dots and cavity QED
A quantum information processing scheme is proposed with semiconductor
quantum dots located in a high-Q single mode QED cavity. The spin degrees of
freedom of one excess conduction electron of the quantum dots are employed as
qubits. Excitonic states, which can be produced ultrafastly with optical
operation, are used as auxiliary states in the realization of quantum gates. We
show how properly tailored ultrafast laser pulses and Pauli-blocking effects,
can be used to achieve a universal encoded quantum computing.Comment: RevTex, 2 figure
Multipartite entangled states in coupled quantum dots and cavity-QED
We investigate the generation of multipartite entangled state in a system of
N quantum dots embedded in a microcavity and examine the emergence of genuine
multipartite entanglement by three different characterizations of entanglement.
At certain times of dynamical evolution one can generate multipartite entangled
coherent exciton states or multiqubit states by initially preparing the
cavity field in a superposition of coherent states or the Fock state with one
photon, respectively. Finally we study environmental effects on multipartite
entanglement generation and find that the decay rate for the entanglement is
proportional to the number of excitons.Comment: 9 pages, 4 figures, to appear in Phys. Rev.
An interferometric complementarity experiment in a bulk Nuclear Magnetic Resonance ensemble
We have experimentally demonstrated the interferometric complementarity,
which relates the distinguishability quantifying the amount of which-way
(WW) information to the fringe visibility characterizing the wave feature
of a quantum entity, in a bulk ensemble by Nuclear Magnetic Resonance (NMR)
techniques. We primarily concern on the intermediate cases: partial fringe
visibility and incomplete WW information. We propose a quantitative measure of
by an alternative geometric strategy and investigate the relation between
and entanglement. By measuring and independently, it turns out that
the duality relation holds for pure quantum states of the
markers.Comment: 13 page, 5 PS figure
On the decay of deformed actinide nuclei
decay through a deformed potential barrier produces significant
mixing of angular momenta when mapped from the nuclear interior to the outside.
Using experimental branching ratios and either semi-classical or
coupled-channels transmission matrices, we have found that there is a set of
internal amplitudes which are essentially constant for all even--even actinide
nuclei. These same amplitudes also give good results for the known anisotropic
particle emission of the favored decays of odd nuclei in the same mass
region.
PACS numbers: 23.60.+e, 24.10.Eq, 27.90.+bComment: 5 pages, latex (revtex style), 2 embedded postscript figures
uuencoded gz-compressed .tar file To appear in Physical Review Letter
Quantum computing with four-particle decoherence-free states in ion trap
Quantum computing gates are proposed to apply on trapped ions in
decoherence-free states. As phase changes due to time evolution of components
with different eigenenergies of quantum superposition are completely frozen,
quantum computing based on this model would be perfect. Possible application of
our scheme in future ion-trap quantum computer is discussed.Comment: 10 pages, no figures. Comments are welcom
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