320 research outputs found
A Novel Algorithm for Effective Vibration Control of Portal Frames
Severe vibrations such as earthquakes threaten to demolish or cause damage to built structures during their lifetime. Mitigation of such damage can be done by using control devices such as actuators. In this paper, an algorithm is proposed to analyze the nonlinear behavior of a portal frame supported by an actuator. The results were compared with those for a frame without actuator. The algorithm was developed in accordance with the Timoshenko beam element theory. ANSYS verified the results for the cases of a frame supported by a damper element and a frame without actuator. The results support the efficiency of the algorithm in reducing frame vibration and top-node displacement
The quantum dynamic capacity formula of a quantum channel
The dynamic capacity theorem characterizes the reliable communication rates
of a quantum channel when combined with the noiseless resources of classical
communication, quantum communication, and entanglement. In prior work, we
proved the converse part of this theorem by making contact with many previous
results in the quantum Shannon theory literature. In this work, we prove the
theorem with an "ab initio" approach, using only the most basic tools in the
quantum information theorist's toolkit: the Alicki-Fannes' inequality, the
chain rule for quantum mutual information, elementary properties of quantum
entropy, and the quantum data processing inequality. The result is a simplified
proof of the theorem that should be more accessible to those unfamiliar with
the quantum Shannon theory literature. We also demonstrate that the "quantum
dynamic capacity formula" characterizes the Pareto optimal trade-off surface
for the full dynamic capacity region. Additivity of this formula simplifies the
computation of the trade-off surface, and we prove that its additivity holds
for the quantum Hadamard channels and the quantum erasure channel. We then
determine exact expressions for and plot the dynamic capacity region of the
quantum dephasing channel, an example from the Hadamard class, and the quantum
erasure channel.Comment: 24 pages, 3 figures; v2 has improved structure and minor corrections;
v3 has correction regarding the optimizatio
B -> Xs l_i^+ l_j^+ Decays with R-parity Violation
We derive the upper bounds on certain products of R-parity- and
lepton-flavor-violating couplings from B \ra X_s {l_i}^+ {l_j}^- decays.
These modes of B-meson decays can constrain the product combinations of the
couplings with one or more heavy generation indices which are comparable with
or stronger than the present bounds. From the studies of the invariant dilepton
mass spectrum and the forward backward asymmetry of the emitted leptons we note
the possibility of detecting R-parity-violating signals even when the total
decay rate due to R-parity violating couplings is comparable with that in the
standard model and discriminating two types of R-parity-violating signals. The
general expectation of the enhancement of the forward backward asymmetry of the
emitted leptons in the minimal supersymmetric standard model with R-parity may
be corrupted by R-parity violation.Comment: 10 pages, Revtex, 1 table and 2 figure
Acupuncture Point Localization Varies Among Acupuncturists
Background: Studies assessing the point-specific effect of acupuncture or the characteristics of acupuncture points (APs) tend to yield inconclusive results. In order to identify a possible confounding factor, we aimed to examine the variability in AP localization by means of a survey. Material and Methods: Attendees of the 14th ICMART (International Council of Medical Acupuncture and Related Techniques) congress as well as DAGfA (German Medical Society of Acupuncture) lecturers and students were asked to locate and mark the APs LI 10 and TH 5 on a research assistant's arm. Identified points were transferred into a coordinate system, and the respective bivariate distribution function was calculated. Additionally, participants filled out a questionnaire about their acupuncture education and experience, the acupuncture style and point localization techniques used most frequently, and their estimation of the size of an AP. Results: The areas of the ellipses, theoretically containing 95% of AP localizations, varied between 44.49 and 5.18 cm(2). The largest distance between 2 identified points was 8.45 cm for LI 10 and 5.3 cm for TH 5. Apart from being trained at the same school, no other factor could be identified that determined the variability in AP localization. Conclusion: Our results indicate that congruity of AP localization among experienced acupuncturists might be low. Although there are some limitations to our results, this possible bias should be taken into account when conducting acupuncture trials and interpreting results of previous acupuncture studies
Public and private communication with a quantum channel and a secret key
We consider using a secret key and a noisy quantum channel to generate
noiseless public communication and noiseless private communication. The optimal
protocol for this setting is the publicly-enhanced private father protocol.
This protocol exploits random coding techniques and "piggybacking" of public
information along with secret-key-assisted private codes. The publicly-enhanced
private father protocol is a generalization of the secret-key-assisted protocol
of Hsieh, Luo, and Brun and a generelization of a protocol for simultaneous
communication of public and private information suggested by Devetak and Shor.Comment: 15 pages, 2 figure
An ensemble study of turbulence in extended QSO nebulae at --1
Turbulent motions in the circumgalactic medium (CGM) play a critical role in
regulating the evolution of galaxies, yet their detailed characterization
remains elusive. Using two-dimensional velocity maps constructed from
spatially-extended [OII] and [OIII] emission, Chen et al. (2023b) measured the
velocity structure functions (VSFs) of four quasar nebulae at
--1.1. One of these exhibits a spectacular Kolmogorov relation.
Here we carry out an ensemble study using an expanded sample incorporating four
new nebulae from three additional QSO fields. The VSFs measured for all eight
nebulae are best explained by subsonic turbulence revealed by the line-emitting
gas, which in turn strongly suggests that the cool gas ( K) is
dynamically coupled to the hot ambient medium. Previous work demonstrates that
the largest nebulae in our sample reside in group environments with clear signs
of tidal interactions, suggesting that environmental effects are vital in
seeding and enhancing turbulence within the gaseous halos, ultimately promoting
the formation of the extended nebulae. No discernible differences are observed
in the VSF properties between radio-loud and radio-quiet QSO fields. We
estimate the turbulent heating rate per unit volume, , in the QSO
nebulae to be -- erg cm s for the cool
phase and -- erg cm s for the hot phase.
This range aligns with measurements in the intracluster medium and star-forming
molecular clouds but is times higher than the
observed inside cool gas clumps on scales kpc using absorption-line
techniques. We discuss the prospect of bridging the gap between emission and
absorption studies by pushing the emission-based VSF measurements to below
kpc.Comment: 23 pages; 7 figures, and 4 tables in main text; 9 figures in
Appendix; accepted by ApJ. Comments welcom
Solar and Atmospheric Neutrino Oscillations and Lepton Flavor Violation in Supersymmetric Models with Right-handed Neutrinos
Taking the solar and the atmospheric neutrino experiments into account we
discuss the lepton flavor violating processes, such as or
, in the minimal supersymmetric standard model with
right-handed neutrinos (MSSMRN) and the supersymmetric SU(5) GUT with
right-handed neutrinos (SU(5)RN). The predicted branching ratio of in the MSSMRN with the MSW large angle solution is so large that it
goes beyond the current experimental bound if the second-generation
right-handed Majorana mass is greater than GeV for . When we take the MSW small angle solution,
the rate is at most about 1/100 of that of the MSW large angle
solution. The 'just so' solution implies of that of the MSW large
angle solution. Also, in the SU(5)RN the large rate naturally
follows from the MSW large angle solution, and the predicted rate is beyond the
current experimental bound if the typical right-handed Majorana mass is
larger than GeV for , similarly to
the MSSMRN. We show the multimass insertion formulas and their applications to
and .Comment: 55 pages, 18 figures, Latex, the final version to be published in
Phys. Rev.
CP Violating B Decays with R-parity Violation
We study CP violating B decays in the minimal supersymmetric standard model
with R-parity violation. We estimate how much R-parity violation modifies the
SM predictions for CP asymmetries in B decays within the present bounds. The
effects of R-parity- and lepton-number-violating couplings on the ratio of the
decay amplitude due to R-parity violation to that of the SM can differ by one
or two orders of magnitudes depending on the models of the left-handed quark
mixing. It is possible to disentangle the R-parity violating effects from those
of the SM and R-parity- conserving supersymmetric models within the present
bounds comparing different CP violating decay amplitudes. We also study the
effects of R-parity- and baryon-number-violating couplings and find that the
effects could be large.Comment: 14 pages. Expanded discussions of the bounds from K decays. To appear
in Phys. Rev.
OGLE-2015-BLG-1649Lb:A gas giant planet around a low-mass dwarf
We report the discovery of an exoplanet from the analysis of the gravitational microlensing event OGLE-2015-BLG-1649 that challenges the core accretion model of planet formation and appears to support the disk instability model. The planet/host-star mass ratio is q = 7.2 Ă 10â3 and the projected separation normalized to the angular Einstein radius is s = 0.9. We conducted high-resolution follow-up observations using the Infrared Camera and Spectrograph (IRCS) camera on the Subaru telescope and are able to place an upper limit on the lens flux. From these measurements we are able to exclude all host stars greater than or equal in mass to a G-type dwarf. We conducted a Bayesian analysis with these new flux constraints included as priors resulting in estimates of the masses of the host star and planet. These are M L = 0.34 ± 0.19 M â and M p =2.5+1.5 -1.4 M jup, respectively. The distance to the system is D L = 4.23 +1.51-1.64 kpc. The projected starâplanet separation is a â„ = 2.07+0.65-0.77 au. The estimated relative lens-source proper motion, ~7.1 mas yrâ1, is fairly high and thus the lens can be better constrained if additional follow-up observations are conducted several years after the event.PostprintPeer reviewe
Sex-differential genetic effect of phosphodiesterase 4D (PDE4D) on carotid atherosclerosis
<p>Abstract</p> <p>Background</p> <p>The phosphodiesterase 4D (PDE4D) gene was reported as a susceptibility gene to stroke. The genetic effect might be attributed to its role in modulating the atherogenic process in the carotid arteries. Using carotid intima-media thickness (IMT) and plaque index as phenotypes, the present study sought to determine the influence of this gene on subclinical atherosclerosis.</p> <p>Methods</p> <p>Carotid ultrasonography was performed on 1013 stroke-free subjects who participated in the health screening programs (age 52.6 ± 12.2; 47.6% men). Genotype distribution was compared among the high-risk (plaque index ℠4), low-risk (index = 1-3), and reference (index = 0) groups. We analyzed continuous IMT data and further dichotomized IMT data using mean plus one standard deviation as the cutoff level. Because the plaque prevalence and IMT values displayed a notable difference between men and women, we carried out sex-specific analyses in addition to analyzing the overall data. Rs702553 at the PDE4D gene was selected because it conferred a risk for young stroke in our previous report. Previous young stroke data (190 cases and 211 controls) with an additional 532 control subjects without ultrasonic data were shown as a cross-validation for the genetic effect.</p> <p>Results</p> <p>In the overall analyses, the rare homozygote of rs702553 led to an OR of 3.1 (p = 0.034) for a plaque index ℠4. When subjects were stratified by sex, the genetic effect was only evident in men but not in women. Comparing male subjects with plaque index ℠4 and those with plaque index = 0, the TT genotype was over-represented (27.6% vs. 13.4%, p = 0.008). For dichotomized IMT data in men, the TT genotype had an OR of 2.1 (p = 0.032) for a thicker IMT at the common carotid artery compared with the (AA + AT) genotypes. In women, neither IMT nor plaque index was associated with rs702553. Similarly, SNP rs702553 was only significant in young stroke men (OR = 1.8, p = 0.025) but not in women (p = 0.27).</p> <p>Conclusions</p> <p>The present study demonstrates a sex-differential effect of PDE4D on IMT, plaque index and stroke, which highlights its influence on various aspects of atherogenesis.</p
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