1,594 research outputs found
Galactic diffuse gamma-ray emission from GeV to PeV energies in light of up-to-date cosmic ray measurements
The diffuse gamma-ray emission between 10 and 1000 TeV from the Galactic
plane was recently measured by the Large High Altitude Air Shower Observatory
(LHAASO). These observations will help tremendously in constraining the
propagation and interaction of cosmic rays in the Milky Way. Additionally, new
measurements of CR spectra reach a very high precision up to 100 TeV energies,
revealing multiple spectral structures of various species. In this work, we
confront the model prediction of the diffuse gamma-ray emission, based on
up-to-date measurements of the local cosmic ray spectra and simplified
propagation setup, with the measurements of diffuse gamma-rays. To better
constrain the low-energy part of the model, we analyze the 14.6 years of
Fermi-LAT data to extract the Galactic diffuse emission between 1 and 500 GeV
from the same sky regions of LHAASO, after subtracting the contribution from
known sources and the isotropic diffuse gamma-ray background. The joint
Fermi-LAT and LHAASO spectra thus cover a very wide energy range from 1 GeV to
1 PeV with small gaps from 0.5 to 10 TeV. Compared with the prediction, we find
that clear excesses between several GeV and ~60 TeV of the diffuse emission
exist. Possible reasons to explain the excesses may include unresolved sources
or more complicated propagation models. We illustrate that an
exponential-cutoff-power-law component with an index of -2.40 and cutoff energy
of ~30 TeV is able to account for such excesses
Requirements-driven self-repairing against environmental failures
Self-repairing approaches have been proposed to alleviate the runtime requirements satisfaction problem by switching to appropriate alternative solutions according to the feedback monitored. However, little has been done formally on analyzing the relations between specific environmental failures and corresponding repairing decisions, making it a challenge to derive a set of alternative solutions to withstand possible environmental failures at runtime. To address these challenges, we propose a requirements-driven self-repairing approach against environmental failures, which combines both development-time and runtime techniques. At the development phase, in a stepwise manner, we formally analyze the issue of self-repairing against environmental failures with the support of the model checking technique, and then design a sufficient and necessary set of alternative solutions to withstand possible environmental failures. The runtime part is a runtime self-repairing mechanism that monitors the operating environment for unsatisfiable situations, and makes self-repairing decisions among alternative solutions in response to the detected environmental failures
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Towards universal health coverage: achievements and challenges of 10 years of healthcare reform in China.
Universal health coverage (UHC) has been identified as a priority for the global health agenda. In 2009, the Chinese government launched a new round of healthcare reform towards UHC, aiming to provide universal coverage of basic healthcare by the end of 2020. We conducted a secondary data analysis and combined it with a literature review, analysing the overview of UHC in China with regard to financial protection, coverage of health services and the reported coverage of the WHO and the World Bank UHC indicators. The results include the following: out-of-pocket expenditures as a percentage of current health expenditures in China have dropped dramatically from 60.13% in 2000 to 35.91% in 2016; the health insurance coverage of the total population jumped from 22.1% in 2003 to 95.1% in 2013; the average life expectancy increased from 72.0 to 76.4, maternal mortality dropped from 59 to 29 per 100 000 live births, the under-5 mortality rate dropped from 36.8 to 9.3 per 1000 live births, and neonatal mortality dropped from 21.4 to 4.7 per 1000 live births between 2000 and 2017; and so on. Our findings show that while China appears to be well on the path to UHC, there are identifiable gaps in service quality and a requirement for ongoing strengthening of financial protections. Some of the key challenges remain to be faced, such as the fragmented and inequitable health delivery system, and the increasing demand for high-quality and value-based service delivery. Given that China has committed to achieving UHC and 'Healthy China 2030', the evidence from this study can be suggestive of furthering on in the UHC journey and taking the policy steps necessary to secure change
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Towards universal health coverage: lessons from 10 years of healthcare reform in China.
Universal health coverage (UHC) is driving the global health agenda. Many countries have embarked on national policy reforms towards this goal, including China. In 2009, the Chinese government launched a new round of healthcare reform towards UHC, aiming to provide universal coverage of basic healthcare by the end of 2020. The year of 2019 marks the 10th anniversary of China's most recent healthcare reform. Sharing China's experience is especially timely for other countries pursuing reforms to achieve UHC. This study describes the social, economic and health context in China, and then reviews the overall progress of healthcare reform (1949 to present), with a focus on the most recent (2009) round of healthcare reform. The study comprehensively analyses key reform initiatives and major achievements according to four aspects: health insurance system, drug supply and security system, medical service system and public health service system. Lessons learnt from China may have important implications for other nations, including continued political support, increased health financing and a strong primary healthcare system as basis
Multi-parameter Tests of General Relativity Using Bayesian Parameter Estimation with Principal Component Analysis for LISA
In the near future, space-borne gravitational wave (GW) detector LISA can
open the window of low-frequency band of GW and provide new tools to test
gravity theories. In this work, we consider multi-parameter tests of GW
generation and propagation where the deformation coefficients are varied
simultaneously in parameter estimation and the principal component analysis
(PCA) method are used to transform posterior samples into new bases for
extracting the most informative components. The dominant components can be
better mesured and constrained and are more sensitive to potential departures
from general relativity (GR). We extend previous works by employing Bayesian
parameter estimation and performing both null tests and tests with injections
of subtle GR-violated signals. We also apply multi-parameter tests with PCA in
the phenomenological test of GW propagation. This work complements previous
works and further demonstrates the enhancement provided by the PCA method.
Considering a supermassive black hole binary system as the GW source, we find
that bounds of the most dominant PCA parameter can be one order of
magnitude tighter than the bounds of original deformation parameter of leading
frequency order. The departures less than in original parameters can
yield significant departures in first 5 dominant PCA parameters.Comment: 16 pages, 6 figure
Crystal structure of N′ -(2, 6-dimethyl-phenyl)benzenecarboximidamide tetrahydrofuran monosolvate
Acknowledgements This work was supported by grants from the Natural Science Foundation of China (grant No. 20702029) and the Natural Science Foundation of Shanxi Province (grant No. 2008011024).Peer reviewedPublisher PD
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