In the Experimental Advanced Superconducting Tokamak(EAST),the reflectivity of the charge exchange recombination spectroscopy(CXRS)first mirror(FM)was dramatically dropped down to 20%of the original value after the op...In the Experimental Advanced Superconducting Tokamak(EAST),the reflectivity of the charge exchange recombination spectroscopy(CXRS)first mirror(FM)was dramatically dropped down to 20%of the original value after the operation of two EAST experimental campaigns from 2014-2015,leading to degradation of the signal intensity of the CXRS diagnostic to an unacceptably low level.The radio frequency(RF)plasma cleaning of the CXRS FM with a dimension of 303×81×76 mm3 and a small curvature of 0.008 mm-1 was performed to remove deposits to recover the reflectivity.After 168 h cleaning by RF plasma,the maximum specular reflectivity of the FM could reach 92%of the original value at 532 nm,making the cleaned CXRS FM eligible to be reused for the CXRS diagnostic in the 2016 EAST campaign.Dedicated tests of sputtering polished mirror samples were performed to explore the cleaning uniformity and possible damage to the mirror surface.The specular reflectivity did not show obvious dependence on locations along the surface with the same cleaning time.The measured surface roughness gradually increased with sputtering time.The reflectivity remained almost unchanged regardless of different sputtering times and locations,indicating negligible damage to the FM surface even after 100 h sputtering.The recontaminated CXRS FM in the 2016 EAST campaign was firstly cleaned for 81 h,and the least reflectivity recovery for areas with relatively thick deposits was only 40%.After continuing cleaning to 147 h,redeposition of the sputtered residual deposits on the FM surface was observed.In the future for in situ cleaning of the FMs in EAST and ITER,deposits should be removed timely when they are very thin taking into account a very long cleaning time and presumable redeposition of thick and nonuniform deposits.展开更多
Ion temperature, as one of the most critical plasma parameters, can be diagnosed by charge exchange recombination spectroscopy (CXRS). Iterative least-squares fitting is conventionally used to analyze CXRS spectra to ...Ion temperature, as one of the most critical plasma parameters, can be diagnosed by charge exchange recombination spectroscopy (CXRS). Iterative least-squares fitting is conventionally used to analyze CXRS spectra to identify the active charge exchange component, which is the result of local interaction between impurity ions with a neutral beam. Due to the limit of the time consumption of the conventional approach (~100 ms per frame), the Experimental Advanced Superconducting Tokamak CXRS data is now analyzed in-between shots. To explore the feasibility of real-time measurement, neural networks are introduced to perform fast estimation of ion temperature. Based on the same four-layer neural network architecture, two neural networks are trained for two central chords according to the ion temperature data acquired from the conventional method. Using the TensorFlow framework, the training procedures are performed by an error back-propagation algorithm with the regularization via the weight decay method. Good agreement in the deduced ion temperature is shown for the neural networks and the conventional approach, while the data processing time is reduced by 3 orders of magnitude (~0.1 ms per frame) by using the neural networks.展开更多
Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high s...Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high spectral resolution spectrometer has been developed for the charge-exchange recombination spectroscopy measurement on the HL-2A tokamak. The simultaneous measurements of He II(468.57 nm), C VI(529.1 nm), and Dα(656.1 nm accompanied by beam emission spectra) with an acquisition frequency up to 400 Hz are achieved by vertically binning the spectrum from each fiber in experiments. Initial results indicate that the system can provide radial profiles of not only ion temperature and rotation velocity,but also concentration of carbon. For the case of helium, the measurements for the ion temperature and rotation velocity are straightforward but the apparent concentration associated with the observed CX intensity is obviously too high. Modeling of the active He II CX feature including plume contributions needs to be carried out to extract the true helium concentration.The spectrometer could become a prototype for the ITER charge-exchange recombination spectroscopy diagnostic and the pilot experiments, as presented here, demonstrate the possibility of impurity concentrations measurements based on the combined measurement of local beam emission and charge-exchange recombination spectroscopy spectra.展开更多
With consideration of the effects of the atomic process and the sight line direction on the charge exchange re-combination spectroscopy （CXRS）, a code used to modify the poloidal CXRS measurement on Tokamak-60 Upgra...With consideration of the effects of the atomic process and the sight line direction on the charge exchange re-combination spectroscopy （CXRS）, a code used to modify the poloidal CXRS measurement on Tokamak-60 Upgrade （JT-60U） in Japan Atomic Energy Research Institute is developed, offering an effective tool to modify the measurement and analyse experimental results further. The results show that the poloidal velocity of ion is overestimated but the ion temperature is underestimated by the poloidal CXRS measurement, and they also indicate that the effect of observation angle on rotation velocity is a dominant one in a core region （r/a 〈 0.65）, whereas in an edge region where the sight line is nearly normal to the neutral beam, the observation angle effect is very small. The difference between the modified velocity and the neoclassical velocity is not larger than the error in measurement. The difference inside the internal transport barrier （ITB） region is 2-3 times larger than that outside the ITB region, and it increases when the effect of excited components in neutral beam is taken into account. The radial electric field profile is affected greatly by the poloidal rotation term, which possibly indicates the correlation between the poloidal rotation and the transport barrier formation.展开更多
Chuanxiong Rhizoma is a widely used Chinese herbal medicine in the past 2000 years.Chuanxiong Rhizoma is composed of volatile oils,phthalide lactones,phenolic acids,polysaccharides and other compounds.To date,more tha...Chuanxiong Rhizoma is a widely used Chinese herbal medicine in the past 2000 years.Chuanxiong Rhizoma is composed of volatile oils,phthalide lactones,phenolic acids,polysaccharides and other compounds.To date,more than 149 compounds in Chuanxiong Rhizoma have been isolated and identified,and some of them have been reported to possess promising biological properties on cardiovascular and central nervous system disorders besides their anti-cancer and antioxidant effects.Modulation of inflammatory mediators and apoptotic factors are believed to contribute to its bioactivities.Analytical methods,such as HPLC,GC and UPLC,are employed for qualitative evaluation of Chuanxiong Rhizoma.In this work,harvest period,growing habitat,processing method and storage,which can affect the quality of Chuanxiong Rhizoma,were also discussed.Comprehensive quality control methods should be developed to ensure the safety,quality and efficacy use of Chuanxiong Rhizoma.Herein,we collected and analyzed the literature of Chuanxiong Rhizoma published on CNKI,ScienceDirect,Springer link,Wiley and PubMed in past two decades,and up-to-date information of Chuanxiong Rhizoma was provided in this paper.We suggested ligustilide,butylidenephthalide and total senkyunolides as the chemical markers to evaluate the quality of Chuanxiong Rhizoma.Additionally,the influences of soil conditions and processing methods on Chuanxiong Rhizoma as future research perspectives should also be further assessed.展开更多
Coronavirus disease 2019 brings a huge burden on the medical industry all over the world.In the background of artificial intelligence(AI)and Internet of Things(IoT)technologies,chest computed tomography(CT)and chest X...Coronavirus disease 2019 brings a huge burden on the medical industry all over the world.In the background of artificial intelligence(AI)and Internet of Things(IoT)technologies,chest computed tomography(CT)and chest Xray(CXR)scans are becoming more intelligent,and playing an increasingly vital role in the diagnosis and treatment of diseases.This paper will introduce the segmentation of methods and applications.CXR and CT diagnosis of COVID-19 based on deep learning,which can be widely used to fight against COVID-19.展开更多
The COVID-19 medical diagnosis method based on individual’s chest X-ray(CXR)is achieved difficultly in the initial research,owing to difficulties in identifying CXR data of COVID-19 individuals.At the beginning of th...The COVID-19 medical diagnosis method based on individual’s chest X-ray(CXR)is achieved difficultly in the initial research,owing to difficulties in identifying CXR data of COVID-19 individuals.At the beginning of the study,infected individuals’CXRs were scarce.The combination of artificial intelligence(AI)and medical diagnosis has been advanced and popular.To solve the difficulties,the interpretability analysis of AI model was used to explore the pathological characteristics of CXR samples infected with COVID-19 and assist in medical diagnosis.The dataset was expanded by data augmentation to avoid overfitting.Transfer learning was used to test different pre-trained models and the unique output layers were designed to complete the model training with few samples.In this study,the output results of four pre-trained models in three different output layers were compared,and the results after data augmentation were compared with the results of the original dataset.The control variable method was used to conduct independent tests of 24 groups.Finally,99.23% accuracy and 98% recall rate were obtained,and the visual results of CXR interpretability analysis were displayed.The network of COVID-19 interpretable diagnosis algorithm has the characteristics of high generalization and lightweight.It can be quickly applied to other urgent tasks with insufficient experimental data.At the same time,interpretability analysis brings new possibilities for medical diagnosis.展开更多
基金National Natural Science Foundation of China(Nos.11975269,11905252,11675218,11675219,11775260,11861131010,11875230)the National Key R&D Program of China(Nos.2017YFA0402500 and 2017YFE0301300)。
文摘In the Experimental Advanced Superconducting Tokamak(EAST),the reflectivity of the charge exchange recombination spectroscopy(CXRS)first mirror(FM)was dramatically dropped down to 20%of the original value after the operation of two EAST experimental campaigns from 2014-2015,leading to degradation of the signal intensity of the CXRS diagnostic to an unacceptably low level.The radio frequency(RF)plasma cleaning of the CXRS FM with a dimension of 303×81×76 mm3 and a small curvature of 0.008 mm-1 was performed to remove deposits to recover the reflectivity.After 168 h cleaning by RF plasma,the maximum specular reflectivity of the FM could reach 92%of the original value at 532 nm,making the cleaned CXRS FM eligible to be reused for the CXRS diagnostic in the 2016 EAST campaign.Dedicated tests of sputtering polished mirror samples were performed to explore the cleaning uniformity and possible damage to the mirror surface.The specular reflectivity did not show obvious dependence on locations along the surface with the same cleaning time.The measured surface roughness gradually increased with sputtering time.The reflectivity remained almost unchanged regardless of different sputtering times and locations,indicating negligible damage to the FM surface even after 100 h sputtering.The recontaminated CXRS FM in the 2016 EAST campaign was firstly cleaned for 81 h,and the least reflectivity recovery for areas with relatively thick deposits was only 40%.After continuing cleaning to 147 h,redeposition of the sputtered residual deposits on the FM surface was observed.In the future for in situ cleaning of the FMs in EAST and ITER,deposits should be removed timely when they are very thin taking into account a very long cleaning time and presumable redeposition of thick and nonuniform deposits.
基金supported by National Natural Science Foundation of China(No.11535013)the National Key Research and Development Program of China(Nos.2017YFA0402500,2018YFE0302100)the Users with Excellence Project of Hefei Science Center CAS(No.2018HSC-UE010)
文摘Ion temperature, as one of the most critical plasma parameters, can be diagnosed by charge exchange recombination spectroscopy (CXRS). Iterative least-squares fitting is conventionally used to analyze CXRS spectra to identify the active charge exchange component, which is the result of local interaction between impurity ions with a neutral beam. Due to the limit of the time consumption of the conventional approach (~100 ms per frame), the Experimental Advanced Superconducting Tokamak CXRS data is now analyzed in-between shots. To explore the feasibility of real-time measurement, neural networks are introduced to perform fast estimation of ion temperature. Based on the same four-layer neural network architecture, two neural networks are trained for two central chords according to the ion temperature data acquired from the conventional method. Using the TensorFlow framework, the training procedures are performed by an error back-propagation algorithm with the regularization via the weight decay method. Good agreement in the deduced ion temperature is shown for the neural networks and the conventional approach, while the data processing time is reduced by 3 orders of magnitude (~0.1 ms per frame) by using the neural networks.
基金supported in part by National Natural Science Foundation of China (Nos.12275070, 12205084, 12305236 and 11675050)in part by the National Key Research and Development Program of China (Nos. 2022YFE03180200, 2022YFE03020001 and 2019YFE03010004)Innovation Program of Southwestern Institute of Physics (No. 202301XWCX001)。
文摘Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high spectral resolution spectrometer has been developed for the charge-exchange recombination spectroscopy measurement on the HL-2A tokamak. The simultaneous measurements of He II(468.57 nm), C VI(529.1 nm), and Dα(656.1 nm accompanied by beam emission spectra) with an acquisition frequency up to 400 Hz are achieved by vertically binning the spectrum from each fiber in experiments. Initial results indicate that the system can provide radial profiles of not only ion temperature and rotation velocity,but also concentration of carbon. For the case of helium, the measurements for the ion temperature and rotation velocity are straightforward but the apparent concentration associated with the observed CX intensity is obviously too high. Modeling of the active He II CX feature including plume contributions needs to be carried out to extract the true helium concentration.The spectrometer could become a prototype for the ITER charge-exchange recombination spectroscopy diagnostic and the pilot experiments, as presented here, demonstrate the possibility of impurity concentrations measurements based on the combined measurement of local beam emission and charge-exchange recombination spectroscopy spectra.
文摘With consideration of the effects of the atomic process and the sight line direction on the charge exchange re-combination spectroscopy （CXRS）, a code used to modify the poloidal CXRS measurement on Tokamak-60 Upgrade （JT-60U） in Japan Atomic Energy Research Institute is developed, offering an effective tool to modify the measurement and analyse experimental results further. The results show that the poloidal velocity of ion is overestimated but the ion temperature is underestimated by the poloidal CXRS measurement, and they also indicate that the effect of observation angle on rotation velocity is a dominant one in a core region （r/a 〈 0.65）, whereas in an edge region where the sight line is nearly normal to the neutral beam, the observation angle effect is very small. The difference between the modified velocity and the neoclassical velocity is not larger than the error in measurement. The difference inside the internal transport barrier （ITB） region is 2-3 times larger than that outside the ITB region, and it increases when the effect of excited components in neutral beam is taken into account. The radial electric field profile is affected greatly by the poloidal rotation term, which possibly indicates the correlation between the poloidal rotation and the transport barrier formation.
基金The 12thinnovation activity plan-of undergraduates in the Shanghai University of Traditional Chinese Medicine(Grant No.2019SHUTCM060)the Natural Science Foundation of Shanghai(Grant No.19ZR1457700)+1 种基金2020 New Agricultural Science Research and Reform Practice Project of the Ministry of Education2020 Key Undergraduate Education Reform Project of Shanghai Colleges。
文摘Chuanxiong Rhizoma is a widely used Chinese herbal medicine in the past 2000 years.Chuanxiong Rhizoma is composed of volatile oils,phthalide lactones,phenolic acids,polysaccharides and other compounds.To date,more than 149 compounds in Chuanxiong Rhizoma have been isolated and identified,and some of them have been reported to possess promising biological properties on cardiovascular and central nervous system disorders besides their anti-cancer and antioxidant effects.Modulation of inflammatory mediators and apoptotic factors are believed to contribute to its bioactivities.Analytical methods,such as HPLC,GC and UPLC,are employed for qualitative evaluation of Chuanxiong Rhizoma.In this work,harvest period,growing habitat,processing method and storage,which can affect the quality of Chuanxiong Rhizoma,were also discussed.Comprehensive quality control methods should be developed to ensure the safety,quality and efficacy use of Chuanxiong Rhizoma.Herein,we collected and analyzed the literature of Chuanxiong Rhizoma published on CNKI,ScienceDirect,Springer link,Wiley and PubMed in past two decades,and up-to-date information of Chuanxiong Rhizoma was provided in this paper.We suggested ligustilide,butylidenephthalide and total senkyunolides as the chemical markers to evaluate the quality of Chuanxiong Rhizoma.Additionally,the influences of soil conditions and processing methods on Chuanxiong Rhizoma as future research perspectives should also be further assessed.
基金supported by the Open Project of State Key Laboratory of Millimeter Wave,Southeast University,China,under Grant K202218.
文摘Coronavirus disease 2019 brings a huge burden on the medical industry all over the world.In the background of artificial intelligence(AI)and Internet of Things(IoT)technologies,chest computed tomography(CT)and chest Xray(CXR)scans are becoming more intelligent,and playing an increasingly vital role in the diagnosis and treatment of diseases.This paper will introduce the segmentation of methods and applications.CXR and CT diagnosis of COVID-19 based on deep learning,which can be widely used to fight against COVID-19.
基金the Southwest Minzu University Graduate Innovative Research Project(No.CX2020SZ95,Master Program)the National Natural Science Foundation of China(No.62073270)+1 种基金the State Ethnic Affairs Commission Innovation Research Team ProjectInnovative Research Team Project of the Education Department of Sichuan Province(No.15TD0050)。
文摘The COVID-19 medical diagnosis method based on individual’s chest X-ray(CXR)is achieved difficultly in the initial research,owing to difficulties in identifying CXR data of COVID-19 individuals.At the beginning of the study,infected individuals’CXRs were scarce.The combination of artificial intelligence(AI)and medical diagnosis has been advanced and popular.To solve the difficulties,the interpretability analysis of AI model was used to explore the pathological characteristics of CXR samples infected with COVID-19 and assist in medical diagnosis.The dataset was expanded by data augmentation to avoid overfitting.Transfer learning was used to test different pre-trained models and the unique output layers were designed to complete the model training with few samples.In this study,the output results of four pre-trained models in three different output layers were compared,and the results after data augmentation were compared with the results of the original dataset.The control variable method was used to conduct independent tests of 24 groups.Finally,99.23% accuracy and 98% recall rate were obtained,and the visual results of CXR interpretability analysis were displayed.The network of COVID-19 interpretable diagnosis algorithm has the characteristics of high generalization and lightweight.It can be quickly applied to other urgent tasks with insufficient experimental data.At the same time,interpretability analysis brings new possibilities for medical diagnosis.
