The impact of resonant magnetic perturbation(RMP)on blob motion and structure in the SOL of the HL-2A tokamak is studied using a gas puff imaging diagnostic.Ellipse fitting is applied to study the structure and motion...The impact of resonant magnetic perturbation(RMP)on blob motion and structure in the SOL of the HL-2A tokamak is studied using a gas puff imaging diagnostic.Ellipse fitting is applied to study the structure and motion of blobs quantitatively.The radial locations,amplitudes and scale sizes of blobs are obtained based on the fitted ellipse.Furthermore,based on the measurement of blob location,the radial and poloidal velocities of blobs are calculated.With the application of RMP,the edge poloidal shear flow is significantly weakened and the wave number spectrum changes from quasisymmetric to significantly up-down asymmetric.The application of RMP also causes the detected blob location to be much further into the far scrape-off layer(SOL)and increases the blob amplitude.Blob poloidal velocity in the SOL is slowed.Larger-size and longer-lifetime blobs are observed with RMP.With the application of RMP,stronger-amplitude and larger-size blobs are detected in the far SOL and they may cause a more serious erosion problem to the first wall.展开更多
As an emerging field of study, granular computing has received much attention. Many models, frameworks, methods and techniques have been proposed and studied. It is perhaps the time to seek for a general and unified v...As an emerging field of study, granular computing has received much attention. Many models, frameworks, methods and techniques have been proposed and studied. It is perhaps the time to seek for a general and unified view so that fundamental issues can be examined and clarified.This paper examines granular computing from three perspectives.By viewing granular computing as a way of structured thinking,we focus on its philosophical foundations in modeling human perception of the reality.By viewing granular computing as a method of structured problem solving,we examine its theoretical and methodological foundations in solving a wide range of real-world problems.By viewing granular computing as a paradigm of information processing,we turn our attention to its more concrete techniques. The three perspectives together offer a holistic view of granular computing.展开更多
To the Editor: Left atrial appendage (LAA) is one of the major sources of atrial arrhythmias in children.[1] But atrial tachycardia (AT) with an epicardial LAA origin is uncommon and usually arises from the base.[2] C...To the Editor: Left atrial appendage (LAA) is one of the major sources of atrial arrhythmias in children.[1] But atrial tachycardia (AT) with an epicardial LAA origin is uncommon and usually arises from the base.[2] Catheter ablation (CA) may be an important strategy for patients with atrial arrhythmia,[3] especially due to the LAA firing trigger.[4] Due to a large number of trabeculations and true epicardial location, endocardial CA in LAA may fail or even cause fatal tamponade.[2,5] The epicardial CA may be an alternative approach.[6] Because the LAA has a very thin wall and may be prone to perforation, caution should be taken when LAA ablation is performed,[4] even during an epicardial ablation. There may be recurrence of AT, and surgical left atrial appendectomy (SAE) may be required.展开更多
基金supported by the National Key Research and Development Program of China(Nos.2022YFE03100002,2022YFE03010004 and 2019YFE03060002)National Natural Science Foundation of China(Nos.U1867222,U1967206 and 51821005)the Sichuan Natural Science Foundation(Nos.2022NSFSC1791 and 2020JDTD0030).
文摘The impact of resonant magnetic perturbation(RMP)on blob motion and structure in the SOL of the HL-2A tokamak is studied using a gas puff imaging diagnostic.Ellipse fitting is applied to study the structure and motion of blobs quantitatively.The radial locations,amplitudes and scale sizes of blobs are obtained based on the fitted ellipse.Furthermore,based on the measurement of blob location,the radial and poloidal velocities of blobs are calculated.With the application of RMP,the edge poloidal shear flow is significantly weakened and the wave number spectrum changes from quasisymmetric to significantly up-down asymmetric.The application of RMP also causes the detected blob location to be much further into the far scrape-off layer(SOL)and increases the blob amplitude.Blob poloidal velocity in the SOL is slowed.Larger-size and longer-lifetime blobs are observed with RMP.With the application of RMP,stronger-amplitude and larger-size blobs are detected in the far SOL and they may cause a more serious erosion problem to the first wall.
文摘As an emerging field of study, granular computing has received much attention. Many models, frameworks, methods and techniques have been proposed and studied. It is perhaps the time to seek for a general and unified view so that fundamental issues can be examined and clarified.This paper examines granular computing from three perspectives.By viewing granular computing as a way of structured thinking,we focus on its philosophical foundations in modeling human perception of the reality.By viewing granular computing as a method of structured problem solving,we examine its theoretical and methodological foundations in solving a wide range of real-world problems.By viewing granular computing as a paradigm of information processing,we turn our attention to its more concrete techniques. The three perspectives together offer a holistic view of granular computing.
文摘To the Editor: Left atrial appendage (LAA) is one of the major sources of atrial arrhythmias in children.[1] But atrial tachycardia (AT) with an epicardial LAA origin is uncommon and usually arises from the base.[2] Catheter ablation (CA) may be an important strategy for patients with atrial arrhythmia,[3] especially due to the LAA firing trigger.[4] Due to a large number of trabeculations and true epicardial location, endocardial CA in LAA may fail or even cause fatal tamponade.[2,5] The epicardial CA may be an alternative approach.[6] Because the LAA has a very thin wall and may be prone to perforation, caution should be taken when LAA ablation is performed,[4] even during an epicardial ablation. There may be recurrence of AT, and surgical left atrial appendectomy (SAE) may be required.
