A5000315199- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Fusion materials and technologies
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Solar and Space Plasma Dynamics
- Superconducting Materials and Applications
- Dust and Plasma Wave Phenomena
- Nuclear Physics and Applications
- Network Security and Intrusion Detection
- Anomaly Detection Techniques and Applications
- Atomic and Subatomic Physics Research
- Radiation Therapy and Dosimetry
- Astro and Planetary Science
- Synthesis and Reactions of Organic Compounds
- Particle Accelerators and Free-Electron Lasers
- Mobile Crowdsensing and Crowdsourcing
- Carbohydrate Chemistry and Synthesis
- Privacy-Preserving Technologies in Data
- Geomagnetism and Paleomagnetism Studies
- Radiation Detection and Scintillator Technologies
- Blockchain Technology Applications and Security
- Internet Traffic Analysis and Secure E-voting
- Atomic and Molecular Physics
General Atomics (United States)
2010-2025
Weifang University of Science and Technology
2022-2024
University of California, Irvine
2013-2022
Hangzhou Dianzi University
2022
Jiangxi Normal University
2017-2022
Zhejiang University
2022
China Guangzhou Analysis and Testing Center
2019
Princeton Plasma Physics Laboratory
2016
Jiangxi University of Technology
2016
University of Kansas Medical Center
2016
Abstract A code that models signals produced by charge-exchange reactions between fast ions and injected neutral beams in tokamak plasmas is described. With the fast-ion distribution function as input, predicts efflux to a particle analyzer (NPA) diagnostic photon radiance of Balmer-alpha light D α (FIDA) diagnostic. Reactions with both primary neutrals cloud secondary “halo” surround beam are treated. Accurate calculation fraction occupy excited atomic states (the collisional-radiative...
Abstract Boosted by mobile communication technologies, Human Activity Recognition (HAR) based on smartphones has attracted more and attentions of researchers. One the main challenges is classification time accuracy in processing long-time dependent sequence samples with noisy or missed data. In this paper, a 1-D Convolution Neural Network (CNN)-based bi-directional Long Short-Term Memory (LSTM) parallel model attention mechanism (ConvBLSTM-PMwA) proposed. The original features sensors are...
FIDASIM is a code that models signals produced by charge-exchange reactions between neutrals and ions (both fast thermal) in magnetically confined plasmas. With the ion distribution function as input, predicts efflux to neutral particle analyzer diagnostic photon radiance of Balmer-alpha light fast-ion D diagnostic, addition many other related quantities. A new, parallelized version Monte Carlo has been developed Fortran90 substantially faster than original interactive data language version....
Low-rate Distributed Denial of Service (LDDoS) attacks have been one the most notorious network security threats, which use periodic slight multi-variate time series pulse flows to degrade quality. Limited by poor data in a single client, powerful and satisfactory LDDoS attack detection model is hard be trained. Federated Learning (FL) promising paradigm offering joint learning through multiple clients. We propose an asynchronous federated arbitration framework based on bidirectional LSTM...
Research on the National Spherical Torus Experiment, NSTX, targets physics understanding needed for extrapolation to a steady-state ST Fusion Nuclear Science Facility, pilot plant, or DEMO. The unique operational space is leveraged test theories next-step tokamak operation, including ITER. Present research also examines implications coming device upgrade, NSTX-U. An energy confinement time, τE, scaling unified varied wall conditions exhibits strong improvement of BTτE with decreased electron...
The National Spherical Torus Experiment (NSTX) has undergone a major upgrade, and the NSTX Upgrade (NSTX-U) Project was completed in summer of 2015.NSTX-U first plasma subsequently achieved, diagnostic control systems have been commissioned, H-mode accessed, magnetic error fields identified mitigated, physics research campaign carried out.During ten run weeks operation, NSTX-U surpassed record pulse-durations toroidal (TF), high-performance ~1 MA plasmas comparable to best sustained near...
Abstract Measurements of beam driven Alfvén Eigenmode (AE) activity in matched deuterium (D) and hydrogen (H) DIII-D plasmas show a dramatic difference unstable mode fast ion transport for given injected power. The dependence the AE spectrum reversed magnetic shear on thermal species is investigated current ramp by varying power sequence discharges fixed at density. In general, Reversed Shear Eigenmodes (RSAEs) Toroidal (TAEs) are with sub-Alfvénic D injection while primarily only RSAEs H...
Abstract Low-rate distributed denial of service attacks, as known LDDoS pose the notorious security risks in cloud computing network. They overload servers and degrade network quality with stealthy strategy. Furthermore, this kind small ratio pulse-like abnormal traffic leads to a serious data scale problem. As result, existing models for detecting minority adversary attacks are insufficient both detection accuracy time consumption. This paper proposes novel multi-scale Convolutional Neural...
Abstract A recent upgrade to the Imaging Neutral Particle Analyzer (INPA) on DIII-D has allowed for first fluctuation measurements using an INPA be taken during a neoclassical tearing mode (NTM). The signal tracked over 150 ms as frequency dropped zero, capturing both NTM with poloidal and toroidal numbers $m/n=2/1$ $3/2$ at double frequency. Analysis shows that signals originate from charge exchange events near edge of plasma, relative amplitudes are greater than 25% duration NTM. Filtered...
Background: Advances in oncological management have contributed to longer survival of patients, even the presence metastases. Consequently, more patients would be expected present with symptomatic bony The major objectives orthopaedic surgical interventions bone metastases include stabilization impending or actual pathological fractures, restoration mobility and gait, resultant reduction overall morbidity during period cancer patient.Purpose: This review was aimed at producing a synoptic...
Abstract A relativistic electron probe has been developed in the DIII-D tokamak, capable of simultaneously resolving pitch angles and energies runaway electrons (REs) for first time. Due to speeds REs, their gyro-orbit size becomes comparable those fast deuterium with tens keV range. This allows measurement RE strike images on a phosphor plane, orbits being deflected by Lorentz force as they pass through pinhole aperture. The positions correspond incident REs. Monte Carlo N-Particle...
Experiments on the National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 40, 557 (2000)] found strong bursts of toroidal Alfvén eigenmode (TAE) activity correlated with abrupt drops in neutron rate. A fairly complete data set offers opportunity to benchmark NOVA [C. Z. Cheng, Phys. Rep. 211, 1 (1992)] and ORBIT [R. B. White M. S. Chance, Fluids 27, 2455 (1984)] codes low aspect ratio tokamak (ST) geometry. The internal structure TAE was modeled good agreement is measurements made...
Fast-ion transport induced by Alfvén eigenmodes (AEs) is studied in beam-heated plasmas on the National Spherical Torus Experiment [Ono et al., Nucl. Fusion 40, 557 (2000)] through space, time, and energy resolved measurements of fast-ion population. losses associated with multiple toroidicity-induced AEs (TAEs), which interact nonlinearly terminate avalanches, are characterized. A depletion range >20 keV, leading to sudden drops up 40% neutron rate over 1 ms, observed a broad spatial...
The mission of the National Spherical Torus Experiment (NSTX) is demonstration physics basis required to extrapolate next steps for spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based (ST-CTF), and support ITER. Key issues are transport, steady state high β operation. To better understand electron new high- k scattering diagnostic was used extensively investigate gyro-scale fluctuations with varying temperature gradient scale length. Results from n = 3...
Improved core high-harmonic fast wave (HHFW) heating at longer wavelengths and during start-up plasma current ramp-up has now been obtained by lowering the edge density with lithium wall conditioning, thereby moving critical for perpendicular fast-wave propagation away from vessel wall. Lithium conditioning allowed significant HHFW electron of deuterium neutral beam injection (NBI) fuelled H-mode plasmas to be observed first time. Large localized modes were immediately after termination rf...
The National Spherical Torus Experiment (NSTX) is currently being upgraded to operate at twice the toroidal field and plasma current (up 1 T 2 MA), with a second, more tangentially aimed neutral beam (NB) for rotation control, allowing pulse lengths up 5 s. Recent NSTX physics analyses have addressed topics that will allow NSTX-Upgrade achieve research goals critical Fusion Nuclear Science Facility. These include producing stable, 100% non-inductive operation in high-performance plasmas,...
Abstract The mission of the low aspect ratio spherical tokamak NSTX-U is to advance physics basis and technical solutions required for optimizing configuration next-step steady-state fusion devices. will ultimately operate at up 2 MA plasma current 1 T toroidal field on axis 5 s, has available 15 MW neutral beam injection power different tangency radii 6 high harmonic fast wave heating. With these capabilities develop understanding control tools ramp-up sustain performance fully...
Abstract Large burst activity, identified as toroidal Alfvén eigenmode (TAE) avalanche, occurs frequently in neutral-beam heated plasmas National Spherical Torus Experiment (NSTX). Based on the typical experimental observation of TAE avalanche NSTX, a self-consistent nonlinear multiple wave-number ( k ∥ ≃ n / R , where mode-number and major radius) simulation associated with avalanches is performed using parameters profiles before occurrence M3D-K input. The wave–wave coupling among...
Combined neutral beam injection and high-harmonic fast-wave (HHFW) heating accelerate deuterium fast ions in the National Spherical Torus Experiment (NSTX). With 1.1 MW of HHFW power, neutron emission rate is about three times larger than comparison discharge without heating. Acceleration above energy evident on an E||B type particle analyzer (NPA), a 4-chord solid state (SSNPA) array 16-channel fast-ion D-alpha (FIDA) diagnostic. The accelerated observed by NPA SSNPA diagnostics mainly come...
The behavior of energetic ions is fundamentally important in the study fusion plasmas. While well-studied tokamak, spherical torus, and stellarator plasmas, relatively little known reversed field pinch plasmas about dynamics fast effects they cause as a large population. These studies are now underway Madison Symmetric Torus with an intense 25 keV, 1 MW hydrogen neutral beam injector (NBI). Measurements time-resolved ion distribution via high energy particle analyzer, well beam-target...
Internal fluctuations arising from energetic-particle-driven instabilities, including both density and radial magnetic field, are measured in a reversed-field-pinch plasma. The peak near the core where fast ions reside shift outward along major radius as instability transits n = 5 to 4 mode. During this transition, strong nonlinear three-wave interaction among multiple modes accompanied by enhanced fast-ion transport is observed.
Abstract In plasmas in the National Spherical Torus Experiment (NSTX) (Ono et al 2000 Nucl. Fusion 40 557) heated with neutral beams, beam ions typically excite energetic particle modes (or fishbones), and toroidal, global or compressional Alfvén eigenmodes. These can redistribute ions, altering driven current profile plasma heating profile, they may affect electron thermal transport cause losses of ions. this paper we present experimental results where these instabilities, by super-thermal...
An overview of recent results from the MST reversed field pinch programme is presented. With neutral beam injection, bursty energetic particle (EP) modes are observed. The profiles magnetic and density fluctuations associated with these EP measured using a far infrared interferometer–polarimeter. Equilibrium reconstructions quasi-single-helicity 3D helical state provided by V3FIT code that now incorporates several MST's advanced diagnostics. orientation structure controlled new resonant...
Abstract 2‐Nitroglycal is a widely used synthon for aminoglycosides synthesis. Herein, we report an efficient method 2‐nitroglycals synthesis using n Bu 4 NNO 3 /Tf 2 O/DTBMP. Using 3‐ O ‐acetyl‐2‐nitroglycals as donors, novel the construction of challenging 1,2‐ cis ‐2,3‐diamino‐2,3‐dideoxyglycosidic linkages was established 4‐pyrrolidinopyridine (PPY) mediated relay glycosylation reaction. The enjoys many features, including very mild reaction condition, excellent regio‐ and...
The five-dimensional finite-orbit Monte Carlo code ORBIT-RF [M. Choi et al., Phys. Plasmas 12, 1 (2005)] is successfully coupled with the two-dimensional full-wave all-orders spectral algorithm (AORSA) [E. F. Jaeger 13, 056101 (2006)] in a self-consistent way to achieve improved predictive modeling for ion cyclotron resonance frequency (ICRF) wave heating experiments present fusion devices and future ITER [R. Aymar Nucl. Fusion 41, 1301 (2001)]. ORBIT-RF/AORSA simulations reproduce fast-ion...