182 research outputs found
The invention of fiberoptic videoguide intubation
Introduction: Airway management is one of the most important medical priorities. Despite its benefits, intubation can be sometimes associated with many complications and hardships. Hard intubation can have dangerous consequences, including hypoxia, increased intracranial pressure, cardiac collapse-vascular, traumatic anatomical areas and inflammation. The purpose of this device building is to reduce such complications.Material and Method: This tool can be used to examine film and photographs of pharyngeal organs, epiglottis, vocal cords and proximal esophagus episodes and the upper esophagus, trachea and bronchi.Discussion: Conventional laryngoscopes and video laryngoscopes are the instruments used in intubation, each of which has its own functional limitations. Of these limitations, it is difficult to intubate that due to the lack of proper view of the anatomical routes, the processor may fail. Fiberopathic videography is a tool that can be used in the chest tube intubation, especially in difficult conditions, operating rooms, and other pre-hospital settings.Results: Fiberopathic videography, a simple and very inexpensive tool that can visualize anatomical paths, shape simplicity directly facilitates the process of commuting and reduces potential complications.Keywords: Fiberoptic, Videoguide, Intubation, Thrace
Discrete breathers assist energy transfer to ac driven nonlinear chains
One-dimensional chain of pointwise particles harmonically coupled with
nearest neighbors and placed in six-order polynomial on-site potentials is
considered. Power of the energy source in the form of single ac driven
particles is calculated numerically for different amplitudes and
frequencies within the linear phonon band. The results for the on-site
potentials with hard and soft nonlinearity types are compared. For the
hard-type nonlinearity, it is shown that when the driving frequency is close to
(far from) the {\em upper} edge of the phonon band, the power of the energy
source normalized to increases (decreases) with increasing . In
contrast, for the soft-type nonlinearity, the normalized power of the energy
source increases (decreases) with increasing when the driving frequency is
close to (far from) the {\em lower} edge of the phonon band. Our further
demonstrations indicate that, in the case of hard (soft) anharmonicity, the
chain can support movable discrete breathers (DBs) with frequencies above
(below) the phonon band. It is the energy source quasi-periodically emitting
moving DBs in the regime with driving frequency close to the DBs frequency,
that induces the increase of the power. Therefore, our results here support the
mechanism that the moving DBs can assist energy transfer from the ac driven
particle to the chain.Comment: 11 pages, 13 figure
Soliton-potential interaction in the nonlinear Klein-Gordon model
The interaction of solitons with external potentials in nonlinear
Klein-Gordon field theory is investigated using an improved model. The
presented model has been constructed with a better approximation for adding the
potential to the Lagrangian through the metric of background space-time. The
results of the model are compared with another model and the differences are
discussed.Comment: 14 pages,8 figure
No Tradeoff between Coherence and Sub-Poissonianity for Heisenberg-Limited Lasers
The Heisenberg limit to laser coherence -- the number of
photons in the maximally populated mode of the laser beam -- is the fourth
power of the number of excitations inside the laser. We generalize the previous
proof of this upper bound scaling by dropping the requirement that the beam
photon statistics be Poissonian (i.e., Mandel's ). We then show that the
relation between and sub-Poissonianity () is win-win, not a
tradeoff. For both regular (non-Markovian) pumping with semi-unitary gain
(which allows ), and random (Markovian) pumping with
optimized gain, is maximized when is minimized.Comment: This is a companion letter to the manuscript entitled "Optimized
Laser Models with Heisenberg-Limited Coherence and Sub-Poissonian Beam Photon
Statistics", arxiv:2208.14082. 6 pages, 2 figure
The Heisenberg limit for laser coherence
To quantify quantum optical coherence requires both the particle- and
wave-natures of light. For an ideal laser beam [1,2,3], it can be thought of
roughly as the number of photons emitted consecutively into the beam with the
same phase. This number, , can be much larger than , the
number of photons in the laser itself. The limit on for an ideal
laser was thought to be of order [4,5]. Here, assuming nothing about
the laser operation, only that it produces a beam with certain properties close
to those of an ideal laser beam, and that it does not have external sources of
coherence, we derive an upper bound: . Moreover, using
the matrix product states (MPSs) method [6,7,8,9], we find a model that
achieves this scaling, and show that it could in principle be realised using
circuit quantum electrodynamics (QED) [10]. Thus is
only a standard quantum limit (SQL); the ultimate quantum limit, or Heisenberg
limit, is quadratically better.Comment: 6 pages, 4 figures, and 31 pages of supplemental information. v2:
This paper is now published [Nature Physics DOI:10.1038/s41567-020-01049-3
(26 October 2020)]. For copyright reasons, this arxiv paper is based on a
version of the paper prior to the accepted (21 August 2020) versio
Optimized Laser Models with Heisenberg-Limited Coherence and Sub-Poissonian Beam Photon Statistics
Recently it has been shown that it is possible for a laser to produce a
stationary beam with a coherence (quantified as the mean photon number at
spectral peak) which scales as the fourth power of the mean number of
excitations stored within the laser, this being quadratically larger than the
standard or Schawlow-Townes limit [1]. Moreover, this was analytically proven
to be the ultimate quantum limit (Heisenberg limit) scaling under defining
conditions for CW lasers, plus a strong assumption about the properties of the
output beam. In Ref. [2], we show that the latter can be replaced by a weaker
assumption, which allows for highly sub-Poissonian output beams, without
changing the upper bound scaling or its achievability. In this Paper, we
provide details of the calculations in Ref. [2], and introduce three new
families of laser models which may be considered as generalizations of those
presented in that work. Each of these families of laser models is parameterized
by a real number, , with corresponding to the original models. The
parameter space of these laser families is numerically investigated in detail,
where we explore the influence of these parameters on both the coherence and
photon statistics of the laser beams. Two distinct regimes for the coherence
may be identified based on the choice of , where for , each family of
models exhibits Heisenberg-limited beam coherence, while for , the
Heisenberg limit is no longer attained. Moreover, in the former regime, we
derive formulae for the beam coherence of each of these three laser families
which agree with the numerics. We find that the optimal parameter is in fact
, not .Comment: This is a companion manuscript to the letter entitled "No Tradeoff
between Coherence and Sub-Poissonianity for Heisenberg-Limited Lasers",
arxiv:2208.14081. 22 pages, 11 figure
Design Space Exploration for Distributed Cyber-Physical Systems: State-of-the-art, Challenges, and Directions
Computer Systems, Imagery and Medi
Isolation and typing of the influenza viruses in the Caspian littoral of Iran
Present study introduces results of common influenza virus strains in the north of Iran. Samples collected from 65 patients with acute respiratory illness by throat washing and swabs, randomly from north of Iran (Mazandaran, Golestan and Guilan provinces). The patients suffered from fever (high), cough, sore throat, general malaise, chill and myalgia. Viruses were isolated by cell culture and confirmed with HA (Hemagglutination) test and then typed by and HI (Hemagglutination Inhibition) test. Out of 65 throat samples, 12 influenza viruses were isolated and typed. Isolated viruses belonged to A (H1N1), A (H3N2) and B influenza viruses. This study showed that Influenza viruses displayed identical pattern to other provinces in Iran and to other countries. To fight against epidemics and pandemics, we should collect enough data about status of influenza each year and data of exact vaccine formulation application for use in different areas of the world. Acquired data has shown that the vaccine for above viruses that confirmed by WHO can result in decreased risks of influenza in at risk cases in provinces of north Iran
A survey on fopid controllers for lfo damping in power systems using synchronous generators, facts devices and inverter-based power plants
In recent decades, various types of control techniques have been proposed for use in power systems. Among them, the use of a proportional–integral–derivative (PID) controller is widely recognized as an effective technique. The generalized type of this controller is the fractional-order PID (FOPID) controller. This type of controller provides a wider range of stability area due to the fractional orders of integrals and derivatives. These types of controllers have been significantly considered as a new approach in power engineering that can enhance the operation and stability of power systems. This paper represents a comprehensive overview of the FOPID controller and its applications in modern power systems for enhancing low-frequency oscillation (LFO) damping. In addition, the performance of this type of controller has been evaluated in a benchmark test system. It can be a driver for the development of FOPID controller applications in modern power systems. Investigation of different pieces of research shows that FOPID controllers, as robust controllers, can play an efficient role in modern power systems
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