338 research outputs found
The Blame Game: Performance Analysis of Speaker Diarization System Components
In this paper we discuss the performance analysis of a speaker diarization system similar to the system that was submitted by ICSI at the NIST RT06s evaluation benchmark. The analysis that is based on a series of oracle experiments, provides a good understanding of the performance of each system component on a test set of twelve conference meetings used in previous NIST benchmarks. Our analysis shows that the speech activity detection component contributes most to the total diarization error rate (23%). The lack of ability to model verlapping speech is also a large source of errors (22%) followed by the component that creates the initial system models (15%)
Filtering the Unknown: Speech Activity Detection in Heterogeneous Video Collections
In this paper we discuss the speech activity detection system that we used for detecting speech regions in the Dutch TRECVID video collection. The system is designed to filter non-speech like music or sound effects out of the signal without the use of predefined non-speech models. Because the system trains its models on-line, it is robust for handling out-of-domain data. The speech activity error rate on an out-of-domain test set, recordings of English conference meetings, was 4.4%. The overall error rate on twelve randomly selected five minute TRECVID fragments was 11.5%
Quantum cloning without signaling
Perfect Quantum Cloning Machines (QCM) would allow to use quantum nonlocality
for arbitrary fast signaling. However perfect QCM cannot exist. We derive a
bound on the fidelity of QCM compatible with the no-signaling constraint. This
bound equals the fidelity of the Bu\v{z}ek-Hillery QCM
Conditional implementation of asymmetrical universal quantum cloning machine
We propose two feasible experimental implementations of an optimal asymmetric
1->2 quantum cloning of a polarization state of photon. Both implementations
are based on a partial and optimal reverse of recent conditional symmetrical
quantum cloning experiments. The reversion procedure is performed only by a
local measurement of one from the clones and ancilla followed by a local
operation on the other clone. The local measurement consists only of a single
unbalanced beam splitter followed in one output by a single photon detector and
the asymmetry of fidelities in the cloning is controlled by a reflectivity of
the beam splitter.Comment: 5 pages, 3 figures, accepted for pulication in PR
Revised Psalm 16
To honor the memory of Brandon Bernard, who was executed by the United States federal government on December 10, 2020
Broken Symmetries in the Entanglement of Formation
We compare some recent computations of the entanglement of formation in
quantum information theory and of the entropy of a subalgebra in quantum
ergodic theory. Both notions require optimization over decompositions of
quantum states. We show that both functionals are strongly related for some
highly symmetric density matrices. We discuss the presence of broken symmetries
in relation with the structure of the optimal decompositions.Comment: 21 pages, LateX, no figure
Entanglement of flux qubits through a joint detection of photons
We study the entanglement creation between two flux qubits interacting with
electromagnetic field modes. No direct interaction between the qubits exists.
Entanglement is reached using entanglement swapping method by an interference
measurement performed on photons. We discuss the influence of off-resonance and
multi-photon initial states on the qubit-qubit entanglement. The presented
scheme is able to drive an initially separable state of two qubits into an
highly entangled state suitable for quantum information processing.Comment: 4 pages, 5 figure
Closure Duration in the Classification of Stops: A statistical analysis
This study was supported by grants from the Harvard-Yenching Institute and the National Science Foundation (#INT-8314687)
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