81 research outputs found
PRZEDZIAŁOWE SYSTEMY ROZMYTE TYPU 2 W ZARZĄDZANIU EMISJĄ TLENKÓW AZOTU
This article is a continuation of research on the possibilities of applications of fuzzy systems and fuzzy systems of higher order to control the air filters. The article presents the author’s fuzzy implications and use of them in the interval type 2 fuzzy controller. Variable inputs which are the concentration’s levels of nitrogen oxides described by linguistic variables, interval type 2 fuzzy sets using the rules of the type IF-THEN controller calculates the filter settings. The results are highly correlated to a data provided by the expert.Artykuł jest kontynuacją badań nad możliwościami zastosowań systemów rozmytych oraz systemów rozmytych wyższych rzędów do sterowania filtrami powietrza. Artykuł prezentuje również autorskie implikacje rozmyte i wykorzystanie ich w interwałowym sterowniku rozmytym typu 2. Zmiennie wejściowe, którymi są poziomy stężenia tlenków azotu, opisane są przy użyciu interwałowych zbiorów rozmytych typu 2. Przy użyciu reguł typu IF-THEN sterownik oblicza wartość nastaw filtra. Uzyskane wyniki są w bardzo wysokim stopniu zgodne z danymi przekazanymi przez eksperta
Higher order fuzzy logic in controlling selective catalytic reduction systems
This paper presents research on applications of fuzzy logic and higher-order fuzzy logic systems to control filters reducing air pollution [1]. The filters use Selective Catalytic Reduction (SCR) method and, as for now, this process is controlled manually by a human expert. The goal of the research is to control an SCR system responsible for emission of nitrogen oxide (NO) and nitrogen dioxide (NO2) to the air, using SCR with ammonia (NH3). There are two higher-order fuzzy logic systems presented, applying interval-valued fuzzy sets and type-2 fuzzy sets, respectively. Fuzzy sets and higher order fuzzy sets describe linguistically levels of nitrogen oxides as the input, and settings of ammonia valve in the air filter as the output. The obtained results are consistent with data provided by experts. Besides, we show that the type-2 fuzzy logic controllers allows us to obtain results much closer to desired parameters of the ammonia valve, than traditional FLS
Preferred Measurements: Optimality and Stability in Quantum Parameter Estimation
We explore precision in a measurement process incorporating pure probe
states, unitary dynamics and complete measurements via a simple formalism. The
concept of `information complement' is introduced. It undermines measurement
precision and its minimization reveals the system properties at an optimal
point. Maximally precise measurements can exhibit independence from the true
value of the estimated parameter, but demanding this severely restricts the
type of viable probe and dynamics, including the requirement that the
Hamiltonian be block-diagonal in a basis of preferred measurements. The
curvature of the information complement near a globally optimal point provides
a new quantification of measurement stability.Comment: 4 pages, 2 figures, in submission. Substantial Extension and
replacement of arXiv:0902.3260v1 in response to Referees' remark
Ab-initio Quantum Enhanced Optical Phase Estimation Using Real-time Feedback Control
Optical phase estimation is a vital measurement primitive that is used to
perform accurate measurements of various physical quantities like length,
velocity and displacements. The precision of such measurements can be largely
enhanced by the use of entangled or squeezed states of light as demonstrated in
a variety of different optical systems. Most of these accounts however deal
with the measurement of a very small shift of an already known phase, which is
in stark contrast to ab-initio phase estimation where the initial phase is
unknown. Here we report on the realization of a quantum enhanced and fully
deterministic phase estimation protocol based on real-time feedback control.
Using robust squeezed states of light combined with a real-time Bayesian
estimation feedback algorithm, we demonstrate deterministic phase estimation
with a precision beyond the quantum shot noise limit. The demonstrated protocol
opens up new opportunities for quantum microscopy, quantum metrology and
quantum information processing.Comment: 5 figure
General framework for estimating the ultimate precision limit in noisy quantum-enhanced metrology
The estimation of parameters characterizing dynamical processes is central to
science and technology. The estimation error changes with the number N of
resources employed in the experiment (which could quantify, for instance, the
number of probes or the probing energy). Typically, it scales as 1/N^(1/2).
Quantum strategies may improve the precision, for noiseless processes, by an
extra factor 1/N^(1/2). For noisy processes, it is not known in general if and
when this improvement can be achieved. Here we propose a general framework for
obtaining attainable and useful lower bounds for the ultimate limit of
precision in noisy systems. We apply this bound to lossy optical interferometry
and atomic spectroscopy in the presence of dephasing, showing that it captures
the main features of the transition from the 1/N to the 1/N^(1/2) behaviour as
N increases, independently of the initial state of the probes, and even with
use of adaptive feedback.Comment: Published in Nature Physics. This is the revised submitted version.
The supplementary material can be found at
http://www.nature.com/nphys/journal/v7/n5/extref/nphys1958-s1.pd
Entanglement-enhanced probing of a delicate material system
Quantum metrology uses entanglement and other quantum effects to improve the
sensitivity of demanding measurements. Probing of delicate systems demands high
sensitivity from limited probe energy and has motivated the field's key
benchmark-the standard quantum limit. Here we report the first
entanglement-enhanced measurement of a delicate material system. We
non-destructively probe an atomic spin ensemble by means of near-resonant
Faraday rotation, a measurement that is limited by probe-induced scattering in
quantum-memory and spin-squeezing applications. We use narrowband,
atom-resonant NOON states to beat the standard quantum limit of sensitivity by
more than five standard deviations, both on a per-photon and per-damage basis.
This demonstrates quantum enhancement with fully realistic loss and noise,
including variable-loss effects. The experiment opens the way to ultra-gentle
probing of single atoms, single molecules, quantum gases and living cells.Comment: 7 pages, 8 figures; Nature Photonics, advance online publication, 16
December 201
Complete characterization of weak, ultrashort near-UV pulses by spectral interferometry
We present a method for a complete characterization of a femtosecond
ultraviolet pulse when a fundamental near-infrared beam is also available. Our
approach relies on generation of second harmonic from the pre-characterized
fundamental, which serves as a reference against which an unknown pulse is
measured using spectral interference (SI). The characterization apparatus is a
modified second harmonic frequency resolved optical gating setup which
additionally allows for taking SI spectrum. The presented method is linear in
the unknown field, simple and sensitive. We checked its accuracy using test
pulses generated in a thick nonlinear crystal, demonstrating the ability to
measure the phase in a broad spectral range, down to 0.1% peak spectral
intensity as well as retrieving pi leaps in the spectral phase
Experimental quantum-enhanced estimation of a lossy phase shift
When standard light sources are employed, the precision of the phase
determination is limited by the shot noise. Quantum entanglement provides means
to exceed this limit with the celebrated example of N00N states that saturate
the ultimate Heisenberg limit on precision, but at the same time are extremely
fragile to losses. In contrast, we provide experimental evidence that
appropriately engineered quantum states outperform both standard and N00N
states in the precision of phase estimation when losses are present.Comment: 5 page
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