14,939 research outputs found
Detection of Minimum-Ionizing Particles and Nuclear Counter Effect with Pure BGO and BSO Crystals with Photodiode Read-out
Long BGO (Bismuth Germanate) and BSO (Bismuth Silicate) crystals coupled with
silicon photodiodes have been used to detect minimum-ionizing particles(MIP).
With a low noise amplifier customized for this purpose, the crystals can detect
MIPs with an excellent signal-to-noise ratio. The NCE(Nuclear Counter Effect}
is also clearly observed and measured. Effect of full and partial wrapping of a
reflector around the crystal on light collection is also studied.Comment: 18 pages, including 5 figures; LaTeX and EP
Constructing Breaker Sequence based System Restoration Strategy with Graph Theory
This paper has proposed a mapping approach to serve as an interface between the branch-bus model and the breaker-based model. In order to find the specific optimal operation for breakers in substations according to the restoration strategies, firstly, the paper has established the breaker-based model for the substation by using graphic theory, and then the optimal operation sequence for breakers has been figured out by adopting Dijkstra algorithm. Finally, a case study for a realistic power system has been analyzed to demonstrate the feasibility and efficiency of the approach.published_or_final_versio
Deciphering Charging Status, Absolute Quantum Efficiency, and Absorption Cross Section of MultiCarrier States in Single Colloidal Quantum Dot
Upon photo- or electrical-excitation, colloidal quantum dots (QDs) are often
found in multi-carrier states due to multi-photon absorption and photo-charging
of the QDs. While many of these multi-carrier states are observed in single-dot
spectroscopy, their properties are not well studied due to random
charging/discharging, emission intensity intermittency, and uncontrolled
surface defects of single QD. Here we report in-situ deciphering the charging
status, and precisely assessing the absorption cross section, and determining
the absolute emission quantum yield of mono-exciton and biexciton states for
neutral, positively-charged, and negatively-charged single core/shell CdSe/CdS
QD. We uncover very different photon statistics of the three charge states in
single QD and unambiguously identify their charge sign together with the
information of their photoluminescence decay dynamics. We then show their
distinct photoluminescence saturation behaviors and evaluated the absolute
values of absorption cross sections and quantum efficiencies of monoexcitons
and biexcitons. We demonstrate that addition of an extra hole or electron in a
QD changes not only its emission properties but also varies its absorption
cross section
Life Assessment of Railway Tunnel Lining Structure Based on Reliability Theory
The reliability of the tunnel lining during its service life has significance for tunnel safety management. To capture the performance of the lining under the effect of deterioration factors, the time-varying reliability theory was applied to predict the service life of the lining. The failure process of the lining structure under an erosion environment was analyzed. The limit state equations of the lining structure were established based on the durability criterion and the bearing capacity criterion, respectively. The time-varying reliability of the tunnel was calculated using the Monte-Carlo method with an engineering example, and the service life of the tunnel under different criteria was predicted based on the target reliability. The results show that the predicted service life of the tunnel is 77.5 years under the durability criterion and 95 years under the bearing capacity criterion, assuming that the tunnel structure is in an erosive environment at the beginning of construction and that no protective measures are taken under the most unfavourable conditions. The durability meets the structural applicability, and the bearing capacity meets the structural safety, which is in line with the actual needs of the project. The study results can provide a basis and reference for the future durability design, life prediction, and maintenance management of similar service tunnels
Bis(2-cyclohexyliminomethyl-4,6-disulfanylphenolato)nickel(II) acetonitrile solvate
In the title compound, [Ni(C13H16NOS2)2]·CH3CN, the NiII atom is four-coordinated by two N,O-bidentate Schiff base ligands, resulting in a distorted tetrahedral coordination for the metal ion
Dynamic Coordinated Condition-Based Maintenance for Multiple Components With External Conditions
published_or_final_versio
Convolutional Neural Networks with Dynamic Regularization
Regularization is commonly used for alleviating overfitting in machine
learning. For convolutional neural networks (CNNs), regularization methods,
such as DropBlock and Shake-Shake, have illustrated the improvement in the
generalization performance. However, these methods lack a self-adaptive ability
throughout training. That is, the regularization strength is fixed to a
predefined schedule, and manual adjustments are required to adapt to various
network architectures. In this paper, we propose a dynamic regularization
method for CNNs. Specifically, we model the regularization strength as a
function of the training loss. According to the change of the training loss,
our method can dynamically adjust the regularization strength in the training
procedure, thereby balancing the underfitting and overfitting of CNNs. With
dynamic regularization, a large-scale model is automatically regularized by the
strong perturbation, and vice versa. Experimental results show that the
proposed method can improve the generalization capability on off-the-shelf
network architectures and outperform state-of-the-art regularization methods.Comment: 7 pages. Accepted for Publication at IEEE TNNL
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