33,101 research outputs found
Entanglement of separate nitrogen-vacancy centers coupled to a whispering-gallery mode cavity
We present a quantum electrodynamical model involving nitrogen-vacancy
centers coupled to a whispering-gallery mode cavity. Two schemes are considered
to create W state and Bell state, respectively. One of the schemes makes use of
the Raman transition with the cavity field virtually excited; The other enables
the Bell state preparation and quantum information transfer by virtue of dark
state evolution and adiabatic passage, which is tolerant to ambient noise and
experimental parameter fluctuations. We justify our schemes by considering the
experimental feasibility and challenge using currently available technology.Comment: 8 pages and 5 figure
Coexistence of localized and itinerant electrons in BaFe2X3 (X = S and Se) revealed by photoemission spectroscopy
We report a photoemission study at room temperature on BaFe2X3 (X = S and Se)
and CsFe2Se3 in which two-leg ladders are formed by the Fe sites. The Fe 2p
core-level peaks of BaFe2X3 are broad and exhibit two components, indicating
that itinerant and localized Fe 3d sites coexist similar to KxFe2-ySe2. The Fe
2p core-level peak of CsFe2Se3 is rather sharp and is accompanied by a
charge-transfer satellite. The insulating ground state of CsFe2Se3 can be
viewed as a Fe2+ Mott insulator in spite of the formal valence of +2.5. The
itinerant versus localized behaviors can be associated with the stability of
chalcogen p holes in the two-leg ladder structure.Comment: 5 pages, 5 figures, Accepted in publication for Physical Review
Deterministically entangling distant nitrogen-vacancy centers by a nanomechanical cantilever
We present a practical scheme by global addressing to deterministically
entangle negatively charged nitrogen-vacancy (N-V) centers in distant diamonds
using a nano-mechanical cantilever with the magnetic tips strongly coupled to
the N-V electron spins. Symmetric Dicke states are generated as an example, and
the experimental feasibility and challenge of our scheme are discussed.Comment: 5 pages, 4 figure
Analysis of Ensiling Suitability of Moringa, a Woody Plant
To effectively use the woody plant resources as animal feed, the ensiling suitability of Moringa including the dynamics of microbial community, chemical composition, and silage fermentation were studied. Tender stems and leaves of Moringa at the full-bloom stage of second cutting was used for silage preparation in Guizhou, China. After 3, 7, 15, 30, and 60 days of ensiling, five silos for each treatment were opened to analyze the fermentation characteristics. Moringa before ensiling contained 104 lactic acid bacteria (LAB), 106 aerobic bacteria, 104 coliform bacteria, 102 yeast, and 104 mold based on colony-forming unit/g of fresh matter (FM). The aerobic bacteria were dominant microbial population in the fresh Moringa. After 3 days of ensiling, the LAB increased as the highest numbers to dominate the silage fermentation. After 7 days of ensiling, the coliform bacteria and mold counts in Moringa silage dropped below the detection levels. The dry matter (DM) of fresh Moringa was 26.57%, their neutral detergent fiber (NDF) and crude protein (CP) contents were 27.40% and 20.90% on a DM basis, respectively. During ensiling, all silages did not emerge great difference in chemical composition. After 7 days of ensiling, all silages displayed a good fermentation patterns, with a low pH value. The result suggested that Moringa can be prepare as silage to be potential woody feed resources for livestock
A Case Study in Matching Test and Proof Coverage
AbstractThis paper studies the complementarity of test and deductive proof processes for Java programs specified in JML (Java Modeling Language). The proof of a program may be long and difficult, especially when automatic provers give up. When a theorem is not automatically proved, there are two possibilities: either the theorem is correct and there are not enough pieces of information to deal with the proof, or the theorem is incorrect. In order to discriminate between those two alternatives, testing techniques can be used. Here, we present experiments around the use of the JACK tool to prove Java programs annotated with JML assertions. When JACK fails to decide proof obligations, we use a combinatorial testing tool, TOBIAS, to produce large test suites that exercise the unproved program parts. The key issue is to establish the relevance of the test suite with respect to the unproved proof obligations. Therefore, we use code coverage techniques: our approach takes advantage of the statement orientation of the JACK tool to compare the statements involved in the unproved proof obligations and the statements covered by the test suite. Finally, we ensure our confidence within the test suites, by evaluating them on mutant program killing exercises. These techniques have been put into practice and are illustrated by a simple case study
Characterization of a small helicopter UAV’s main rotor blade through Image Processing
Abstract: Image processing is applied to the task of characterizing the response of a miniature helicopter’s main rotor to collective control inputs under static conditions. The objective is to measure the pitch of the main rotor blade in relation to collective control inputs and deduce a transfer function model from the data..
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