1,670 research outputs found
Magic wavelengths for the 6s^2\,^1S_0-6s6p\,^3P_1^o transition in ytterbium atom
The static and dynamic electric-dipole polarizabilities of the 6s^2\,^1S_0
and 6s6p\,^3P_1^o states of Yb are calculated by using the relativistic ab
initio method. Focusing on the red detuning region to the
6s^2\,^1S_0-6s6p\,^3P_1^o transition, we find two magic wavelengths at
1035.7(2) nm and 612.9(2) nm for the 6s^2\,^1S_0-6s6p\,^3P_1^o, M_J=0
transition and three magic wavelengthes at 1517.68(6) nm, 1036.0(3) nm and
858(12) nm for the 6s^2\,^1S_0-6s6p\,^3P_1^o, M_J=\pm1 transitions. Such
magic wavelengths are of particular interest for attaining the
state-insensitive cooling, trapping, and quantum manipulation of neutral Yb
atom.Comment: 13 pages, 3 figure
LINE: Large-scale Information Network Embedding
This paper studies the problem of embedding very large information networks
into low-dimensional vector spaces, which is useful in many tasks such as
visualization, node classification, and link prediction. Most existing graph
embedding methods do not scale for real world information networks which
usually contain millions of nodes. In this paper, we propose a novel network
embedding method called the "LINE," which is suitable for arbitrary types of
information networks: undirected, directed, and/or weighted. The method
optimizes a carefully designed objective function that preserves both the local
and global network structures. An edge-sampling algorithm is proposed that
addresses the limitation of the classical stochastic gradient descent and
improves both the effectiveness and the efficiency of the inference. Empirical
experiments prove the effectiveness of the LINE on a variety of real-world
information networks, including language networks, social networks, and
citation networks. The algorithm is very efficient, which is able to learn the
embedding of a network with millions of vertices and billions of edges in a few
hours on a typical single machine. The source code of the LINE is available
online.Comment: WWW 201
Differential measurement of atmospheric refraction with a telescope with double fields of view
For the sake of complete theoretical research of atmospheric refraction, the
atmospheric refraction under the condition of lower angles of elevation is
still worthy to be analyzed and explored. In some engineering applications, the
objects with larger zenith distance must be observed sometimes. Carrying out
observational research of the atmospheric refraction at lower angles of
elevation has an important significance. It has been considered difficult to
measure the atmospheric refraction at lower angles of elevation. A new idea for
determining atmospheric refraction by utilizing differential measurement with
double fields of view is proposed. Taking the observational principle of
HIPPARCOS satellite as a reference, a schematic prototype with double fields of
view was developed. In August of 2013, experimental observations were carried
out and the atmospheric refractions at lower angles of elevation can be
obtained by the schematic prototype. The measured value of the atmospheric
refraction at the zenith distance of 78.8 degree is , and the
feasibility of differential measurement of atmospheric refraction with double
fields of view was justified. The limitations of the schematic prototype such
as inadequate ability of gathering light, lack of accurate meteorological data
recording and lower automatic level of observation and data processing were
also pointed out, which need to be improved in subsequent work.Comment: 10 pages, 6 figure
Analysis on the Construction Path of “Golden Course” of International Commercial Law in International Trade Major from the New Liberal Arts Perspective
Under the background of “new liberal arts”, curriculum innovation and development become an important way to improve the quality of talent training. Therefore, the construction of “golden course” as a breakthrough is the focus of talent training and professional development in undergraduate colleges. Based on the analysis of the necessity of constructing the “golden course” of International Commercial Law in international trade major from the perspective of new liberal arts and the existing problems in course construction, this paper constructs the “five-in-one” teaching mode of “Golden Course” of International Commercial Law in international trade major by combining the teaching idea of “pre-class + after-class + in-class”, and explores the cultivation path of foreign trade law compound talents. To cultivate high-quality practical foreign trade talents who meet the needs of the construction of a trade power and the development of the country and society
Sharp sufficient conditions for stable recovery of block sparse signals by block orthogonal matching pursuit
In this paper, we use the block orthogonal matching pursuit (BOMP) algorithm to recover block sparse signals x from measurements y = Ax + v, where v is an ℓ2-bounded noise vector (i.e., kvk2 ≤ ǫ for some constant ǫ). We investigate some sufficient conditions based on the block restricted isometry property (block-RIP) for exact (when v = 0) and stable (when v , 0) recovery of block sparse signals x. First, on the one hand, we show that if A satisfies the block-RIP with δK+1 1 and √2/2 ≤ δ < 1, the recovery of x may fail in K iterations for a sensingmatrix A which satisfies the block-RIP with δK+1 = δ. Finally, we study some sufficient conditions for partial recovery of block sparse signals. Specifically, if A satisfies the block-RIP with δK+1 < √2/2, then BOMP is guaranteed to recover some blocks of x if these blocks satisfy a sufficient condition. We further show that this condition is also sharp
Poly[[tetraaquabis(μ3-1H-benzimidazole-5,6-dicarboxylato)dicobalt(II)] trihydrate]
The title complex, {[Co2(C9H4N2O4)2(H2O)4]·3H2O}n, was synthesized hydrothermally. The unique CoII ion is coordinated in a distorted octahedral coordination environment by two water molecules and three symmetry-related 1H-benzimidazole-5,6-dicarboxylate (Hbidc) ligands. The Hbidc ligands coordinate via a bis-chelating and mono-chelating carboxylate group and by an imidazole group N atom, bridging the CoII ions and forming an extended two-dimensional structure in the ab plane. In the crystal structure, intermolecular N—H⋯O and O—H⋯O hydrogen bonds connect complex and solvent water molecules, forming a three-dimensional supermolecular network. One of the solvent water molecules lies on a twofold rotation axis
METHOD BASED DEA FOR MULTIPLE ATTRIBUTE DECISION MAKING
Using DEA, A new concept for multiple attribute decision making and analysis, relative efficiency and weak relative efficiency is proposed with its relations to the Pareto efficiency being discussed, its economic interpretation and geometrical meaning and existence theorem being given. On the basis of this concept, a new method of unified evaluations and decision making and analysis is designed. Finally, some useful suggestion are given for the applications in R&D project selection and science & technology achievement evaluations. Key words: DEA, multiple attribute decision making, project selection and evaluatio
Sno/scaRNAbase: a curated database for small nucleolar RNAs and cajal body-specific RNAs
Small nucleolar RNAs (snoRNAs) and Cajal body-specific RNAs (scaRNAs) are named for their subcellular localization within nucleoli and Cajal bodies (conserved subnuclear organelles present in the nucleoplasm), respectively. They have been found to play important roles in rRNA, tRNA, snRNAs, and even mRNA modification and processing. All snoRNAs fall in two categories, box C/D snoRNAs and box H/ACA snoRNAs, according to their distinct sequence and secondary structure features. Box C/D snoRNAs and box H/ACA snoRNAs mainly function in guiding 2′-O-ribose methylation and pseudouridilation, respectively. ScaRNAs possess both box C/D snoRNA and box H/ACA snoRNA sequence motif features, but guide snRNA modifications that are transcribed by RNA polymerase II. Here we present a Web-based sno/scaRNA database, called sno/scaRNAbase, to facilitate the sno/scaRNA research in terms of providing a more comprehensive knowledge base. Covering 1979 records derived from 85 organisms for the first time, sno/scaRNAbase is not only dedicated to filling gaps between existing organism-specific sno/scaRNA databases that are focused on different sno/scaRNA aspects, but also provides sno/scaRNA scientists with an opportunity to adopt a unified nomenclature for sno/scaRNAs. Derived from a systematic literature curation and annotation effort, the sno/scaRNAbase provides an easy-to-use gateway to important sno/scaRNA features such as sequence motifs, possible functions, homologues, secondary structures, genomics organization, sno/scaRNA gene's chromosome location, and more. Approximate searches, in addition to accurate and straightforward searches, make the database search more flexible. A BLAST search engine is implemented to enable blast of query sequences against all sno/scaRNAbase sequences. Thus our sno/scaRNAbase serves as a more uniform and friendly platform for sno/scaRNA research. The database is free available at
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