19,153 research outputs found
Confinement induced resonances in anharmonic waveguides
We develop the theory of anharmonic confinement-induced resonances (ACIR).
These are caused by anharmonic excitation of the transverse motion of the
center of mass (COM) of two bound atoms in a waveguide. As the transverse
confinement becomes anisotropic, we find that the COM resonant solutions split
for a quasi-1D system, in agreement with recent experiments. This is not found
in harmonic confinement theories. A new resonance appears for repulsive
couplings () for a quasi-2D system, which is also not seen with
harmonic confinement. After inclusion of anharmonic energy corrections within
perturbation theory, we find that these ACIR resonances agree extremely well
with anomalous 1D and 2D confinement induced resonance positions observed in
recent experiments. Multiple even and odd order transverse ACIR resonances are
identified in experimental data, including up to N=4 transverse COM quantum
numbers.Comment: 16 pages,6 fugure
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Research progress on coal mine laser methane sensor
This paper discusses the research progress of low-power technology of laser methane sensors for coal mine. On the basis of environment of coal mines, such as ultra-long-distance transmission and high stability, a series of studies have been carried out. The preliminary results have been achieved in the research of low power consumption, temperature and pressure compensation and reliability design. The technology is applied to various products in coal mines, and achieves high stability and high reliability in products such as laser methane sensor, laser methane detection alarm device, wireless laser methane detection alarm device, and optic fiber multichannel laser methane sensor. Experimental testing and analysis of the characteristics of laser methane sensors, combined with the actual application
Representations and classification of traveling wave solutions to Sinh-G{\"o}rdon equation
Two concepts named atom solution and combinatory solution are defined. The
classification of all single traveling wave atom solutions to Sinh-G{\"o}rdon
equation is obtained, and qualitative properties of solutions are discussed. In
particular, we point out that some qualitative properties derived intuitively
from dynamic system method aren't true. In final, we prove that our solutions
to Sinh-G{\"o}rdon equation include all solutions obtained in the paper[Fu Z T
et al, Commu. in Theor. Phys.(Beijing) 2006 45 55]. Through an example, we show
how to give some new identities on Jacobian elliptic functions.Comment: 12 pages. accepted by Communications in theoretical physics (Beijing
Occurrence of cancer at multiple sites: Towards distinguishing multigenesis from metastasis
<p>Abstract</p> <p>Background</p> <p>Occurrence of tumors at multiple sites is a hallmark of malignant cancers and contributes to the high mortality of cancers. The formation of multi-site cancers (MSCs) has conventionally been regarded as a result of hematogenous metastasis. However, some MSCs may appear as unusual in the sense of vascular dissemination pattern and therefore be explained by alternative metastasis models or even by non-metastatic independent formation mechanisms.</p> <p>Results</p> <p>Through literature review and incorporation of recent advance in understanding aging and development, we identified two alternative mechanisms for the independent formation of MSCs: 1) formation of separate tumors from cancer-initiating cells (CICs) mutated at an early stage of development and then diverging as to their physical locations upon further development, 2) formation of separate tumors from different CICs that contain mutations in some convergent ways. Either of these processes does not require long-distance migration and/or vascular dissemination of cancer cells from a primary site to a secondary site. Thus, we classify the formation of these MSCs from indigenous CICs (iCICs) into a new mechanistic category of tumor formation – multigenesis.</p> <p>Conclusion</p> <p>A multigenesis view on multi-site cancer (MSCs) may offer explanations for some "unusual metastasis" and has important implications for designing expanded strategies for the diagnosis and treatment of cancers.</p> <p>Reviewers</p> <p>This article was reviewed by Carlo C. Maley nominated by Laura F. Landweber and Razvan T. Radulescu nominated by David R. Kaplan. For the full reviews, please go to the Reviewers' comments section.</p
Heavy and Light Pentaquark Chiral Lagrangian
Using the SU(3) flavor symmetry, we construct the chiral Lagrangians for the
light and heavy pentaquarks. The correction from the nonzero quark is taken
into account perturbatively. We derive the Gell-MannOkubo type relations for
various pentaquark multiplet masses and Coleman-Glashow relations for
anti-sextet heavy pentaquark magnetic moments. We study possible decays of
pentaquarks into conventional hadrons. We also study the interactions between
and within various pentaquark multiplets and derive their coupling constants in
the symmetry limit. Possible kinematically allowed pionic decay modes are
pointed out
The Euler Number of Bloch States Manifold and the Quantum Phases in Gapped Fermionic Systems
We propose a topological Euler number to characterize nontrivial topological
phases of gapped fermionic systems, which originates from the Gauss-Bonnet
theorem on the Riemannian structure of Bloch states established by the real
part of the quantum geometric tensor in momentum space. Meanwhile, the
imaginary part of the geometric tensor corresponds to the Berry curvature which
leads to the Chern number characterization. We discuss the topological numbers
induced by the geometric tensor analytically in a general two-band model. As an
example, we show that the zero-temperature phase diagram of a transverse field
XY spin chain can be distinguished by the Euler characteristic number of the
Bloch states manifold in a (1+1)-dimensional Bloch momentum space
Accelerated Particle Swarm Optimization and Support Vector Machine for Business Optimization and Applications
Business optimization is becoming increasingly important because all business
activities aim to maximize the profit and performance of products and services,
under limited resources and appropriate constraints. Recent developments in
support vector machine and metaheuristics show many advantages of these
techniques. In particular, particle swarm optimization is now widely used in
solving tough optimization problems. In this paper, we use a combination of a
recently developed Accelerated PSO and a nonlinear support vector machine to
form a framework for solving business optimization problems. We first apply the
proposed APSO-SVM to production optimization, and then use it for income
prediction and project scheduling. We also carry out some parametric studies
and discuss the advantages of the proposed metaheuristic SVM.Comment: 12 page
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