47,347 research outputs found
Decomposition of multicomponent mass spectra using Bayesian probability theory
We present a method for the decomposition of mass spectra of mixture gases
using Bayesian probability theory. The method works without any calibration
measurement and therefore applies also to the analysis of spectra containing
unstable species. For the example of mixtures of three different hydrocarbon
gases the algorithm provides concentrations and cracking coefficients of each
mixture component as well as their confidence intervals. The amount of
information needed to obtain reliable results and its relation to the accuracy
of our analysis are discussed
An Electronic Mach-Zehnder Quantum Eraser
We propose an electronic quantum eraser in which the electrons are injected
into a mesoscopic conductor at the quantum Hall regime. The conductor is
composed of a two-path interferometer which is an electronic analogue of the
optical Mach-Zehnder interferometer, and a quantum point contact detector
capacitively coupled to the interferometer. While the interference of the
output current at the interferometer is shown to be suppressed by the
which-path information, we show that the which-path information is erased by
the zero-frequency cross correlation measurement between the interferometer and
the detector output leads. We also investigate a modified setup in which the
detector is replaced by a two-path interferometer.We show that the path
distinguishability and the visibility of the joint detection can be controlled
in a continuous manner, and satisfy a complementarity relation for the
entangled electrons.Comment: 5 pages, 2 figure
Determination of Stray Inductance of Low-Inductive Laminated Planar Multiport Busbars Using Vector Synthesis Method
Laminated busbars connect capacitors with switching power modules, and they are designed to have low stray inductance to minimize electromagnetic interference. Attempts to accurately measure the stray inductance of these busbars have not been successful. The challenge lies with the capacitors, as they excite the busbar producing their individual stray inductances. These individual stray inductances cannot be arithmetically averaged to establish the total stray inductance that applies when all the capacitors excite the busbar at the same time. It is also not possible to measure the stray inductance by simultaneous excitation of each capacitor port using impedance analyzers. This paper presents a solution to the above dilemma. A vector synthesis method is proposed, whereby the individual stray inductance from each capacitor port is measured using an impedance analyzer. Each stray inductance is then mapped into an xyz frame with a distinct direction. This mapping exercise allows the data to be vectored. The total stray inductance is then the sum of all the vectors. The effectiveness of the proposed method is demonstrated on a busbar designed for H-bridge inverters by comparing the simulation and practical results. The absolute error of the total stray inductance between the simulation and the proposed method is 0.48 nH. The proposed method improves the accuracy by 14.9% compared to the conventional technique in measuring stray inductances
An Augmentation Hybrid System for Document Classification and Rating.
This paper introduces an augmentation hybrid system, referred to as Rated MCRDR. It uses Multiple Classification Ripple Down Rules (MCRDR), a simple and effective knowledge acquisition technique, combined with a neural network
New limits on "odderon" amplitudes from analyticity constraints
In studies of high energy and scattering, the odd (under
crossing) forward scattering amplitude accounts for the difference between the
and cross sections. Typically, it is taken as
(),
which has as , where is the
ratio of the real to the imaginary portion of the forward scattering amplitude.
However, the odd-signatured amplitude can have in principle a strikingly
different behavior, ranging from having non-zero constant to
having as , the maximal behavior
allowed by analyticity and the Froissart bound. We reanalyze high energy
and scattering data, using new analyticity constraints, in order to
put new and precise limits on the magnitude of ``odderon'' amplitudes.Comment: 13 pages LaTex, 6 figure
Conformal Invariance of Black Hole Temperature
It is shown that the surface gravity and temperature of a stationary black
hole are invariant under conformal transformations of the metric that are the
identity at infinity. More precisely, we find a conformal invariant definition
of the surface gravity of a conformal Killing horizon that agrees with the
usual definition(s) for a true Killing horizon and is proportional to the
temperature as defined by Hawking radiation. This result is reconciled with the
intimate relation between the trace anomaly and the Hawking effect, despite the
{\it non}invariance of the trace anomaly under conformal transformations.Comment: 8 pages, plain LaTeX, NSF-ITP-93-9
- …