Integrated data analysis on the electron temperature profile of HL-2A with the Bayesian probability inference method

Data analysis on tokamak plasmas is mainly based on various diagnostic systems,which are usually modularized and independent of each other.This leads to a large amount of data not being fully and effectively exploited so that it is not conducive to revealing the deep physical mechanism.In this work,Bayesian probability inference with machine learning methods have been applied to the electron cyclotron emission and Thomson scattering diagnostic systems on HL-2A/2M,and the effects of integrated data analysis(IDA)on the electron temperature of HL-2A with Bayesian probability inference are demonstrated.A program is developed to infer the whole electron temperature profile with a confidence interval,and the program can be applied in online analysis.The IDA results show that the full profile of the electron temperature can be obtained and the diagnostic information is more comprehensive and abundant with IDA.The inference models for electron temperature analysis are established and the developed programs will serve as an experimental data analysis tool for HL-2A/2M in the near future.

Tomography of emissivity for Doppler coherence imaging spectroscopy diagnostic in HL-2A

A newly developed Doppler coherence imaging spectroscopy(CIS)technique has been implemented in the HL-2 A tokamak for carbon impurity emissivity and flow measurement.In CIS diagnostics,the emissivity and flow profiles inside the plasma are measured by a camera from the line-integrated emissivity and line-averaged flow,respectively.A standard inference method,called tomographic inversion,is necessary.Such an inversion is relatively challenging due to the ill-conditioned nature.In this article,we report the recent application and comparison of two different tomography algorithms,Gaussian process tomography and Tikhonov tomography,on light intensity measured by CIS,including feasibility and benchmark studies.Finally,the tomographic results for real measurement data in HL-2A are presented.

Hospital Strain and COVID-19 Fatality—England,April 2020–March 2022

Summary What is already known about this topic?During the coronavirus disease 2019(COVID-19)pandemic,tremendous efforts have been made in countries to suppress epidemic peaks and strengthen hospital services to avoid hospital strain and ultimately reduce the risk of death from COVID-19.However,there is limited empirical evidence that hospital strain increases COVID-19 deaths.

Characteristics and Containment of 74 Imported COVID-19 Outbreaks: Experiences, Lessons, and Implications — China, 2020–2021

What is already known about this topic?After the initial coronavirus disease 2019(COVID-19)outbreak in Wuhan,China,the outbreaks during the dynamic-zero policy period in the mainland of China have not been systematically documented.What is added by this report?We summarized the characteristics of 74 imported COVID-19 outbreaks between March 19,2020 and December 31,2021.All outbreaks of early severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants were successfully contained with the aid of nucleic acid testing,modern communication technologies,and non-pharmacological interventions.What are the implications for public health practice?These findings provide us with confidence for the containment of future emerging infectious diseases alike at early stages to prevent pandemics or to win time to gain experience,develop vaccines and drugs,vaccinate people,and wait for the possible lessening of the virus’pathogenicity.