155 research outputs found
TGMM: Combining Parse Tree with GPU for Scalable Multilingual and Multi-Granularity Code Clone Detection
The rapid evolution of programming languages and software systems has
necessitated the implementation of multilingual and scalable clone detection
tools. However, it is difficult to achieve the above requirements at the same
time. Most existing tools only focus on one challenge. In this work, we propose
TGMM, a tree and GPU-based tool for multilingual and multi-granularity code
clone detection. By generating parse trees based on user-provided grammar
files, TGMM can extract code blocks at a specified granularity and detect
Type-3 clones efficiently. In order to show the performance of TGMM, we compare
it with seven state-of-the-art tools in terms of recall, precision, and
execution time. TGMM ranks first in execution time and precision, while its
recall is comparable to the others. Moreover, we analyzed the language
extensibility of TGMM across 30 mainstream programming languages. Out of these,
a total of 25 languages were supported, while the remaining five currently lack
the necessary grammar files. Finally, we analyzed the clone characteristics of
nine popular languages at five common granularities, hoping to inspire future
researchers. The source code of TGMM is available at:
https://github.com/TGMM24/TGMM.git.Comment: 14 pages, 7 figure
Quantitative Determination of the Critical Points of Mott Metal-Insulator Transition in Strongly Correlated Systems
The Mottness is at the heart of the essential physics in a strongly
correlated system as many novel quantum phenomena occur at the metallic phase
near the Mott metal-insulator transition. We investigate the Mott
metal-insulator transition in a strongly-correlated electron system based on
the Hubbard model. The on-site moment evaluated by the dynamical mean-field
theory is employed to depict the Mott metal-insulator transition. Conveniently,
the on-site moment is a more proper order parameter to quantitatively determine
the Mott critical point, in comparison with the corresponding quasiparticle
coherent weight. Moreover, this order parameter also gives a consistent
description of two distinct forms of the critical points of the Mott
metal-insulator transition.Comment: 6 pages, 4 figure
Enhanced photoelectrochemical activities of a nanocomposite film with a bamboo leaf-like structured TiO(2) layer on TiO(2) nanotube arrays
A novel nanocomposite TiO(2) film consisting of a bamboo leaf-like nano TiO(2) layer on a nanotubular TiO(2) arrays surface is synthesized by electrochemical anodization with wet chemical pretreatment; it shows almost three times higher activity as compared to that of nanotubular TiO(2) arrays alone.National Natural Science Foundation of China[51072170, 20773100, 20620130427]; National Basic Research Program of China[2007CB935603]; National High Technology Research and Development Program of China[2009AA03Z327
The cosmic ray test of MRPCs for the BESIII ETOF upgrade
In order to improve the particle identification capability of the Beijing
Spectrometer III (BESIII),t is proposed to upgrade the current endcap
time-of-flight (ETOF) detector with multi-gap resistive plate chamber (MRPC)
technology. Aiming at extending ETOF overall time resolution better than 100ps,
the whole system including MRPC detectors, new-designed Front End Electronics
(FEE), CLOCK module, fast control boards and time to digital modules (TDIG),
was built up and operated online 3 months under the cosmic ray. The main
purposes of cosmic ray test are checking the detectors' construction quality,
testing the joint operation of all instruments and guaranteeing the performance
of the system. The results imply MRPC time resolution better than 100,
efficiency is about 98 and the noise rate of strip is lower than
1() at normal threshold range, the details are discussed and
analyzed specifically in this paper. The test indicates that the whole ETOF
system would work well and satisfy the requirements of upgrade
Detection of the Diffuse Supernova Neutrino Background with JUNO
As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO
Potential of Core-Collapse Supernova Neutrino Detection at JUNO
JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve
Real-time Monitoring for the Next Core-Collapse Supernova in JUNO
Core-collapse supernova (CCSN) is one of the most energetic astrophysical
events in the Universe. The early and prompt detection of neutrinos before
(pre-SN) and during the SN burst is a unique opportunity to realize the
multi-messenger observation of the CCSN events. In this work, we describe the
monitoring concept and present the sensitivity of the system to the pre-SN and
SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is
a 20 kton liquid scintillator detector under construction in South China. The
real-time monitoring system is designed with both the prompt monitors on the
electronic board and online monitors at the data acquisition stage, in order to
ensure both the alert speed and alert coverage of progenitor stars. By assuming
a false alert rate of 1 per year, this monitoring system can be sensitive to
the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos
up to about 370 (360) kpc for a progenitor mass of 30 for the case
of normal (inverted) mass ordering. The pointing ability of the CCSN is
evaluated by using the accumulated event anisotropy of the inverse beta decay
interactions from pre-SN or SN neutrinos, which, along with the early alert,
can play important roles for the followup multi-messenger observations of the
next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure
The study of doubly charmed pentaquark with the SU(3) symmetry
We study the masses and lifetimes of doubly charmed pentaquark primarily. The operation of masses carried out by the doubly
heavy triquark-diquark model, whose results suggests the existence of stable
states with the parity . The roughly
calculation about lifetimes show the short magnitudes,
for the parity
and for . Since
the pentaquark is interpreted as the stable bound states against
strong decays, then we will focus on the production and possible decay channels
of the pentaquark in the next step, the study would be fairly valuable supports
for future experiments. For completeness, we systematically studied the
production from and the decay modes in the framework SU(3)
flavor symmetry, including the processes of semi-leptonic and two body
non-leptonic decays. Synthetically, we make a collection of the golden
channels.Comment: 18 pages, 4 figure
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