6,815 research outputs found
Neutron and muon-induced background studies for the AMoRE double-beta decay experiment
AMoRE (Advanced Mo-based Rare process Experiment) is an experiment to search
a neutrinoless double-beta decay of Mo in molybdate crystals. The
neutron and muon-induced backgrounds are crucial to obtain the zero-background
level (< counts/(keVkgyr)) for the AMoRE-II experiment,
which is the second phase of the AMoRE project, planned to run at YEMI
underground laboratory. To evaluate the effects of neutron and muon-induced
backgrounds, we performed Geant4 Monte Carlo simulations and studied a
shielding strategy for the AMORE-II experiment. Neutron-induced backgrounds
were also included in the study. In this paper, we estimated the background
level in the presence of possible shielding structures, which meet the
background requirement for the AMoRE-II experiment
Secrecy content of two-qubit states
We analyze the set of two-qubit states from which a secret key can be
extracted by single-copy measurements plus classical processing of the
outcomes. We introduce a key distillation protocol and give the corresponding
necessary and sufficient condition for positive key extraction. Our results
imply that the critical error rate derived by Chau, Phys. Rev. A {\bf 66},
060302 (2002), for a secure key distribution using the six-state scheme is
tight. Remarkably, an optimal eavesdropping attack against this protocol does
not require any coherent quantum operation.Comment: 5 pages, RevTe
Update of axion CDM energy density
We improve the estimate of the axion CDM energy density by considering the
new values of current quark masses, the QCD phase transition effect and a
possible anharmonic effect.Comment: 7 pages, 6 figures. References are added. A factor is correcte
A Tool for Generating Reduced-Order Models from Building Energy Simulation Input Files to Enable Optimal Design and Control Analysis
Representing multi-zone building envelope systems with linear time invariant state-space forms provides a way of applying various advanced control methodologies for better design and control of buildings. For example, system properties such as time constant and frequency response of building envelopes can be easily investigated with the help of control toolkits such as Matlab/Simulink and a reduced-order model can be developed by applying a model order reduction technique, once a reliable LTI building representation is developed. However, in order to make the LTI representation approach useful for industry, an interfacing tool that automatically extracts building system information from input files of popular building energy simulation (BES) tools and constructs a physical thermal network from the data is needed. This paper presents a conceptual strategy to interpret object (class) of a building energy simulation software and a methodology to develop a high fidelity LTI thermal network model. A case study applying this approach is provided which utilizes a model-order reduction method that converts a BES building envelope model for a multi-zone building into a reduced-order LTI model (ROM). Comparisons of predicted building load profiles and computation times between the BES model and ROM are also provided
Einstein-aether theory, violation of Lorentz invariance, and metric-affine gravity
We show that the Einstein-aether theory of Jacobson and Mattingly (J&M) can
be understood in the framework of the metric-affine (gauge theory of) gravity
(MAG). We achieve this by relating the aether vector field of J&M to certain
post-Riemannian nonmetricity pieces contained in an independent linear
connection of spacetime. Then, for the aether, a corresponding geometrical
curvature-square Lagrangian with a massive piece can be formulated
straightforwardly. We find an exact spherically symmetric solution of our
model.Comment: Revtex4, 38 pages, 1 figur
How to hide a secret direction
We present a procedure to share a secret spatial direction in the absence of
a common reference frame using a multipartite quantum state. The procedure
guarantees that the parties can determine the direction if they perform joint
measurements on the state, but fail to do so if they restrict themselves to
local operations and classical communication (LOCC). We calculate the fidelity
for joint measurements, give bounds on the fidelity achievable by LOCC, and
prove that there is a non-vanishing gap between the two of them, even in the
limit of infinitely many copies. The robustness of the procedure under particle
loss is also studied. As a by-product we find bounds on the probability of
discriminating by LOCC between the invariant subspaces of total angular
momentum N/2 and N/2-1 in a system of N elementary spins.Comment: 4 pages, 1 figur
Optimal entanglement witnesses from generalized reduction and Robertson maps
We provide a generalization of the reduction and Robertson positive maps in
matrix algebras. They give rise to a new class of optimal entanglement
witnesses. Their structural physical approximation is analyzed. As a byproduct
we provide a new examples of PPT (Positive Partial Transpose) entangled states.Comment: 14 page
Electron affinity of Li: A state-selective measurement
We have investigated the threshold of photodetachment of Li^- leading to the
formation of the residual Li atom in the state. The excited residual
atom was selectively photoionized via an intermediate Rydberg state and the
resulting Li^+ ion was detected. A collinear laser-ion beam geometry enabled
both high resolution and sensitivity to be attained. We have demonstrated the
potential of this state selective photodetachment spectroscopic method by
improving the accuracy of Li electron affinity measurements an order of
magnitude. From a fit to the Wigner law in the threshold region, we obtained a
Li electron affinity of 0.618 049(20) eV.Comment: 5 pages,6 figures,22 reference
Effects of 3D-printed polycaprolactone/��-tricalcium phosphate membranes on guided bone regeneration
This study was conducted to compare 3D-printed polycaprolactone (PCL) and polycaprolactone/��-tricalcium phosphate (PCL/��-TCP) membranes with a conventional commercial collagen membrane in terms of their abilities to facilitate guided bone regeneration (GBR). Fabricated membranes were tested for dry and wet mechanical properties. Fibroblasts and preosteoblasts were seeded into the membranes and rates and patterns of proliferation were analyzed using a kit-8 assay and by scanning electron microscopy. Osteogenic differentiation was verified by alizarin red S and alkaline phosphatase (ALP) staining. An in vivo experiment was performed using an alveolar bone defect beagle model, in which defects in three dogs were covered with different membranes. CT and histological analyses at eight weeks after surgery revealed that 3D-printed PCL/��-TCP membranes were more effective than 3D-printed PCL, and substantially better than conventional collagen membranes in terms of biocompatibility and bone regeneration and, thus, at facilitating GBR. ? 2017 by the authors. Licensee MDPI, Basel, Switzerland.118Ysciescopu
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