956 research outputs found
The dual Meissner effect in SU(2) Landau gauge
The dual Meissner effect is observed without monopoles in quenched SU(2) QCD
with Landau gauge-fixing. Abelian as well as non-Abelian electric fields are
squeezed. Magnetic displacement currents which are time-dependent Abelian
magnetic fields play a role of solenoidal currents squeezing Abelian electric
fields. Monopoles are not always necessary to the dual Meissner effect. The
squeezing of the electric flux means the dual London equation and the
massiveness of the Abelian electric fields as an asymptotic field. The mass
generation of the Abelian electric fields is related to a gluon condensate
of mass dimension 2.Comment: 10 page, 12 Postscript figures, Talk presented at Quark Confinement
and the Hadron Spectrum VI 2004, Sardinia, 21-25 Sep 200
Parallel Dual Tabu Search for Capacitor Placement in Smart Grids
AbstractThis paper proposes parallel dual tabu search (PDTS) for capacitor placement in smart grids. The proposed method makes use of the dual code of the initial vale to make solution candidates diverse. The capacitor placement is one of important problems to maintain the nodal voltage profile in the distribution network level of smart grids. The problem formulation of capacitor placement may be expressed as a combinatorial optimization problem of capacitor banks. In this paper, a new method is proposed to improve the performance of tabu search (TS) of meta-heuristics. Although meta-heuristics are not affected by the initial value in smaller systems, they are inclined to give different solutions with different initial values in large-scale problems. In practice, it is very important to set up a good initial value for tabu search although a priori knowledge is not available in general. This paper focuses on the dual code of the initial value to create another initial value systematically. Mathematically, the dual code is orthogonal to the original one so that the solution search is carried out to keep the diversity of solution candidates from two most different directions. The effectiveness of the proposed method is demonstrated in a sample system
Vibrotactile Stimulus Frequency Optimization for the Haptic BCI Prototype
The paper presents results from a psychophysical study conducted to optimize
vibrotactile stimuli delivered to subject finger tips in order to evoke the
somatosensory responses to be utilized next in a haptic brain computer
interface (hBCI) paradigm. We also present the preliminary EEG evoked responses
for the chosen stimulating frequency. The obtained results confirm our
hypothesis that the hBCI paradigm concept is valid and it will allow for rapid
stimuli presentation in order to improve information-transfer-rate (ITR) of the
BCI.Comment: The 6th International Conference on Soft Computing and Intelligent
Systems and The 13th International Symposium on Advanced Intelligent Systems,
201
TXRF FOR SEMICONDUCTOR APPLICATIONS
ABSTRACT This paper discusses the application of TXRF for semiconductor process characterization. The depth profile of the analyte element plays a critical role in accurate determination by TXRF. In order to achieve reliable quantification, a method for preparing standard and crosscheck samples, named "Immersion in Alkaline Hydrogen Peroxide Solution (IAP)," is proposed. The method offers a good level of reproducibility of depth profiles as well as area1 and in-batch uniformity. Certain improvements of TXRF instruments are also discussed. The purity of the background spectra is critical in ultra-trace analysis, and improvements in instrumentation such as Au-LP excitation, a dual multilayer monochromator, and an x-y-8 stage actually reduced the background to help enable the identification of trace elements. We tested the performance of the recently improved TXRF instruments on IAP wafers intentionally contaminated with trace Cu, and demonstrated that a reallo9 atoms cm-2 analysis can actually be achieved
Development of an experimental method of systematically estimating protein expression limits in HEK293 cells
Protein overexpression sometimes causes cellular defects, although the underlying mechanism is still unknown. A protein's expression limit, which triggers cellular defects, is a useful indication of the underlying mechanism. In this study, we developed an experimental method of estimating the expression limits of target proteins in the human embryonic kidney cell line HEK293 by measuring the proteins' expression levels in cells that survived after the high-copy introduction of plasmid DNA by which the proteins were expressed under a strong cytomegalovirus promoter. The expression limits of nonfluorescent target proteins were indirectly estimated by measuring the levels of green fluorescent protein (GFP) connected to the target proteins with the self-cleaving sequence P2A. The expression limit of a model GFP was similar to 5.0% of the total protein, and sustained GFP overexpression caused cell death. The expression limits of GFPs with mitochondria-targeting signals and endoplasmic reticulum localization signals were 1.6% and 0.38%, respectively. The expression limits of four proteins involved in vesicular trafficking were far lower compared to a red fluorescent protein. The protein expression limit estimation method developed will be valuable for defining toxic proteins and consequences of protein overexpression
Multi-command Tactile Brain Computer Interface: A Feasibility Study
The study presented explores the extent to which tactile stimuli delivered to
the ten digits of a BCI-naive subject can serve as a platform for a brain
computer interface (BCI) that could be used in an interactive application such
as robotic vehicle operation. The ten fingertips are used to evoke
somatosensory brain responses, thus defining a tactile brain computer interface
(tBCI). Experimental results on subjects performing online (real-time) tBCI,
using stimuli with a moderately fast inter-stimulus-interval (ISI), provide a
validation of the tBCI prototype, while the feasibility of the concept is
illuminated through information-transfer rates obtained through the case study.Comment: Haptic and Audio Interaction Design 2013, Daejeon, Korea, April
18-19, 2013, 15 pages, 4 figures, The final publication will be available at
link.springer.co
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