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A high-resolution micro-electro-mechanical resonant tilt sensor
This paper reports on the design and experimental evaluation of a high-resolution Micro-Electro-Mechanical (MEM) tilt sensor based on resonant sensing principles. The sensors incorporate a pair of double-ended tuning fork (DETF) resonant strain gauges, the mechanical resonant frequencies of which shift in proportion to an axial force induced by variations in the component of gravitational acceleration along a specified input axis. An analysis of the structural design of such sensors (using analytical and finite element modelling) is presented, followed by experimental test results from device prototypes fabricated using a silicon-on-insulator (SOI) MEMS technology. This paper reports measurement conducted to quantify sensor scale factor, temperature sensitivity, scale factor linearity and resolution. It is demonstrated that such sensors provide a ±90 degree dynamic range for tilt measurements with a temperature sensitivity of nearly 500 ppb/K (equating to systematic sensitivity error of approximately 0.007 degree/K). When configured as a tilt sensor, it is also shown that the scale factor linearity is better than 1.4% for a ±20° tilt angle range. The bias stability of a micro-fabricated prototype is below 500 ng for an averaging time of 0.8 seconds making these devices a potentially attractive option for numerous precision tilt sensing applications.This is the author's accepted manuscript. The final version is available from Elsevier at http://www.sciencedirect.com/science/article/pii/S0924424714004385
Multi-quark components in baryons
A brief review on some recent progresses in our understanding of multi-quark
components in baryons is presented. The multi-quark components in baryons seem
to be mainly in colored quark cluster configurations rather than in ``meson
cloud'' configurations or in the form of a sea of quark-antiquark pairs. The
colored quark cluster multi-quark picture gives a natural explanation of
empirical indications for a positive strangeness magnetic moment of the
proton and the longstanding mass-reverse problem of S11(1535) and \mu_s$ of the proton is given.Comment: Contribution to the International Conference on QCD and Hadronic
Physics, June 16-20, 2005, Beijin
Spin correlated interferometry for polarized and unpolarized photons on a beam splitter
Spin interferometry of the 4th order for independent polarized as well as
unpolarized photons arriving simultaneously at a beam splitter and exhibiting
spin correlation while leaving it, is formulated and discussed in the quantum
approach. Beam splitter is recognized as a source of genuine singlet photon
states. Also, typical nonclassical beating between photons taking part in the
interference of the 4th order is given a polarization dependent explanation.Comment: RevTeX, 19 pages, 1 ps figure, author web page at
http://m3k.grad.hr/pavici
Intersections of homogeneous Cantor sets and beta-expansions
Let be the -part homogeneous Cantor set with
. Any string with
such that is called a code of . Let
be the set of having a unique code,
and let be the set of which make the intersection a
self-similar set. We characterize the set in a
geometrical and algebraical way, and give a sufficient and necessary condition
for . Using techniques from beta-expansions, we
show that there is a critical point , which is a
transcendental number, such that has positive
Hausdorff dimension if , and contains countably
infinite many elements if . Moreover, there exists a
second critical point
such that
has positive Hausdorff dimension if
, and contains countably infinite many elements if
.Comment: 23 pages, 4 figure
Cyclooxygenase inhibitors use is associated with reduced risk of esophageal adenocarcinoma in patients with Barrett's esophagus: A meta-analysis
Background: Esophageal adenocarcinoma (EAC) has high mortality and is increasing in incidence. Barrett's esophagus (BE) increases the risk for EAC. Studies have reported inconsistent findings on the association between use of cyclooxygenase (COX) inhibitors and the risk of neoplastic progression in BE patients. Therefore, we performed a meta-analysis to investigate this association. Methods: A meta-analysis was undertaken among a total of 9 observational studies using fixed- and random-effects models, comprising 5446 participants; 605 had EAC or high-grade dysplasia (HGD). Results: Overall, COX inhibitors use was associated with a reduced risk of EAC/HGD among BE patients (relative risk (RR)=0.64, 95% confidence interval (CI)=0.53-0.77). Aspirin use also reduced the risk of EAC/HGD (RR=0.63, 95% CI=0.43-0.94), as well as non-aspirin COX inhibitors (RR=0.50, 95% CI=0.32-0.78). The chemopreventive effect seemed to be independent of duration response. Conclusions: Cyclooxygenase inhibitors use is associated with a reduced risk of developing EAC in patients with BE. Both low-dose aspirin and non-aspirin COX inhibitors are associated with a reduced risk of neoplasia. More well-designed randomised controlled trials are needed to increase our understanding of the chemopreventive effect of COX inhibitors
Quantum-enhanced radiometry via approximate quantum error correction
By exploiting the exotic quantum states of a probe, it is possible to realize
efficient sensors that are attractive for practical metrology applications and
fundamental studies. Similar to other quantum technologies, quantum sensing is
suffering from noises and thus the experimental developments are hindered.
Although theoretical schemes based on quantum error correction (QEC) have been
proposed to combat noises, their demonstrations are prevented by the stringent
experimental requirements, such as perfect quantum operations and the
orthogonal condition between the sensing interaction Hamiltonian and the noise
Lindbladians. Here, we report an experimental demonstration of a quantum
enhancement in sensing with a bosonic probe with different encodings, by
exploring the large Hilbert space of the bosonic mode and developing both the
approximate QEC and the quantum jump tracking approaches. In a practical
radiometry scenario, we attain a 5.3 dB enhancement of sensitivity, which
reaches when measuring the excitation
population of a receiver mode. Our results demonstrate the potential of quantum
sensing with near-term quantum technologies, not only shedding new light on the
quantum advantage of sensing by revealing its difference from other quantum
applications, but also stimulating further efforts on bosonic quantum
technologies.Comment: 8 pages, 4 figure
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