150 research outputs found
Estimating the distribution of inflation expectations
In this paper, we use survey data to estimate the shape of the distribution of inflation expectations. However, unlike previous studies, we do not assume a distribution a priori. We employ an applied approximation method using normal distribution: Cornish-Fisher expansion. Skewness and kurtosis may provide necessary information for understanding the shape of the distribution of inflation expectations. The estimated inflation expectations contain slight biasedness and are not fully efficient, but some superiority can be verified.Inflation expectations, Survey data, Skewness and kurtosis
The features of degenerative lumbar scoliosis in rheumatoid arthritis patients -matched cohort study
Quantum detector tomography of superconducting nanostrip photon-number-resolving detector
Superconducting nanostrip photon detectors have been used as single photon
detectors, which can discriminate only photons' presence or absence. It has
recently been found that they can discriminate the number of photons by
analyzing the output signal waveform, and they are expected to be used in
various fields, especially in optical quantum information processing. Here, we
improve the photon-number-resolving performance for light with a high-average
photon number by pattern matching of the output signal waveform. Furthermore,
we estimate the positive-operator-valued measure of the detector by a quantum
detector tomography. The result shows that the device has
photon-number-resolving performance up to five photons without any multiplexing
or arraying, indicating that it is useful as a photon-number-resolving
detector.Comment: 11 pages, 5 figure
Clinical and Radiological Outcomes after Microscopic Bilateral Decompression via a Unilateral Approach for Degenerative Lumbar Disease: Minimum 5-Year Follow-Up
Study DesignA retrospective study.PurposeTo assess postoperative bone regrowth at surgical sites after lumbar decompression with >5 years of follow-up. Postoperative preservation of facet joints and segmental spinal instability following surgery were also evaluated.Overview of LiteraturePrevious reports have documented bone regrowth after conventional laminectomy or laminotomy and several factors associated with new bone formation.MethodsForty-nine patients who underwent microscopic bilateral decompression via a unilateral approach at L4–5 were reviewed. Primary outcomes included correlations among postoperative bone regrowth, preservation of facet joints, radiographic parameters, and clinical outcomes. Secondary outcomes included comparative analyses of radiographic parameters and clinical outcomes among preoperative diagnoses (lumbar spinal stenosis, degenerative spondylolisthesis, and degenerative lumbar scoliosis).ResultsThe average value of bone regrowth at the latest follow-up was significantly higher on the dorsal side of the facet joint (3.4 mm) than on the ventral side (1.3 mm). Percent facet joint preservation was significantly smaller on the approach side (79.2%) than on the contralateral side (95.2%). Bone regrowth showed a significant inverse correlation with age, but no significant correlation was observed with facet joint preservation, gender, postoperative segmental spinal motion, or clinical outcomes. Subanalysis of these data revealed that bone regrowth at the latest follow-up was significantly greater in patients with degenerative lumbar scoliosis than in those with lumbar spinal stenosis. Postoperative segmental spinal motion at L4–L5 did not progress significantly in patients with degenerative spondylolisthesis or degenerative lumbar scoliosis compared with those with lumbar spinal stenosis.ConclusionsMicroscopic bilateral decompression via a unilateral approach prevents postoperative spinal instability because of satisfactory preservation of facet joints, which may be the primary reason for inadequate bone regrowth. Postoperative bone regrowth was not related to clinical outcomes and postoperative segmental spinal instability
Frustrated quantum-spin system on a triangle coupled with lattice vibrations - Correspondence to Longuet-Higgins et al.'s Jahn-Teller model -
We investigate the quantum three spin model
of spin on a triangle, in which spins are coupled with
lattice-vibrational modes through the exchange interaction depending on
distances between spin sites. The present model corresponds to the dynamic
Jahn-Teller system proposed by Longuet-Higgins {\it et al.},
Proc.R.Soc.A.{\bf 244},1(1958). This correspondence is revealed by using the
transformation to Nakamura-Bishop's bases proposed in Phys.Rev.Lett.{\bf
54},861(1985). Furthermore, we elucidate the relationship between the behavior
of a chiral order parameter and
that of the electronic orbital angular momentum in vibronic model: The regular oscillatory behavior of the expectation value
. The increase of the additional
anharmonicity(chaoticity) is found to yield a rapidly decaying irregular
oscillation of
A Remote Operated Quadruped Robot System for Investigation of Reactor Building
ABSTRACT A remote operated quadruped robot has been developed for disaster site which can move on stairs, slopes, and uneven floor under the radiation-polluted environment, such as TEPCO Fukushima Daiichi nuclear power plants In particular, the control method for stable walking and the remote operation system have been developed to move on stairs in the reactor building. We applied this robot to investigation of suspicious water leakage points in reactor building at Fukushima Daiichi nuclear power plants unit
Single-shot single-mode optical two-parameter displacement estimation beyond classical limit
Uncertainty principle prohibits the precise measurement of both components of
displacement parameters in phase space. We have theoretically shown that this
limit can be beaten using single-photon states, in a single-shot and
single-mode setting [F. Hanamura et al., Phys. Rev. A 104, 062601 (2021)]. In
this paper, we validate this by experimentally beating the classical limit. In
optics, this is the first experiment to estimate both parameters of
displacement using non-Gaussian states. This result is related to many
important applications, such as quantum error correction.Comment: 5 pages, 4 figure
Generation of Highly Pure Single-Photon State at Telecommunication Wavelength
Telecommunication wavelength with well-developed optical communication
technologies and low losses in the waveguide are advantageous for quantum
applications. However, an experimental generation of non-classical states
called non-Gaussian states at the telecommunication wavelength is still
underdeveloped. Here, we generate highly-pure-single-photon states, one of the
most primitive non-Gaussian states, by using a heralding scheme with an optical
parametric oscillator and a superconducting nano-strip photon detector. The
Wigner negativity, the indicator of non-classicality, of the generated single
photon state is , corresponded to of single
photon and the best record of the minimum value at all wavelengths. The
quantum-optics-technology we establish can be easily applied to the generation
of various types of quantum states, opening up the possibility of
continuous-variable-quantum-information processing at telecommunication
wavelengths.Comment: 10 pages, 6 figure
Chaos and its quantization in dynamical Jahn-Teller systems
We investigate the Jahn-Teller system for the purpose to
reveal the nature of quantum chaos in crystals. This system simulates the
interaction between the nuclear vibrational modes and the electronic motion in
non-Kramers doublets for multiplets of transition-metal ions. Inclusion of the
anharmonic potential due to the trigonal symmetry in crystals makes the system
nonintegrable and chaotic. Besides the quantal analysis of the transition from
Poisson to Wigner level statistics with increasing the strength of
anharmonicity, we study the effect of chaos on the electronic orbital angular
momentum and explore the magnetic -factor as a function of the system's
energy. The regular oscillation of this factor changes to a rapidly-decaying
irregular oscillation by increasing the anharmonicity (chaoticity).Comment: 8 pages, 6 figure
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