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Zhang S, Ma Q, Liang S, Xiao H, Zhuang G, Zou Y, Tan H, Liu J, Zhang Y, Zhang L, Feng X, Xue L, Hu D, Cui F, Liang X. Annual economic burden of hepatitis B virus-related diseases among hospitalized patients in twelve cities in China. J Viral Hepat 2016; 23:202-10. [PMID: 26663525 DOI: 10.1111/jvh.12482] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 08/26/2015] [Indexed: 12/09/2022]
Abstract
A nationwide survey of hepatitis B virus (HBV)-associated economic burden has not previously been performed in China. The purpose of this study was to examine the direct, indirect, and intangible costs of HBV-related diseases within the span of one year. A random sample was taken from specialty and general hospitals across 12 cities in six provinces of China. Intangible costs were estimated based on willingness to pay or open-ended answers provided by patients. The results showed that 27 hospitals were enrolled, with a sample population of 4726 patients (77.7% response rate). The average annual costs were $4454.0 (direct), $924.3 (indirect), and $6611.10 (intangible), corresponding to 37.3%, 7.7%, and 55.1% of the total costs, respectively. The direct medical fees were substantially greater than the non-medical fees. Annual indirect costs were divided into outpatient ($112.9) and inpatient ($811.40) loss of income. The intangible costs of chronic HBV were notably higher than either the direct or indirect costs, consistent with the social stigma in China. The comparison amongst individual cities for the average ratio of direct to indirect costs revealed that the sizes of ratios were negatively correlated with the socioeconomic status of the regions. This study suggested that as a whole in China, the HBV-related diseases caused a heavy financial burden which was positively associated with disease severity. Although the intangible costs coincided with a high prevalence of discrimination against CHB patients in Chinese society, our study may serve as future reference for detailed exploration.
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Liu LJ, Yu KX, Zhang M, Zhuang G, Li X, Yuan T, Rao B, Zhao Q. Measurement of toroidal vessel eddy current during plasma disruption on J-TEXT. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:013501. [PMID: 26827315 DOI: 10.1063/1.4939035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this paper, we have employed a thin, printed circuit board eddy current array in order to determine the radial distribution of the azimuthal component of the eddy current density at the surface of a steel plate. The eddy current in the steel plate can be calculated by analytical methods under the simplifying assumptions that the steel plate is infinitely large and the exciting current is of uniform distribution. The measurement on the steel plate shows that this method has high spatial resolution. Then, we extended this methodology to a toroidal geometry with the objective of determining the poloidal distribution of the toroidal component of the eddy current density associated with plasma disruption in a fusion reactor called J-TEXT. The preliminary measured result is consistent with the analysis and calculation results on the J-TEXT vacuum vessel.
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Liu L, Rao B, Zhang M, Yu K, Zhuang G. Analysis of eddy currents in the two-half isolated vacuum vessel of an iron core tokamak. FUSION ENGINEERING AND DESIGN 2015. [DOI: 10.1016/j.fusengdes.2015.10.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pan M, Zhang M, Li T, Zheng W, Zhao Q, Rao B, Zhuang G. Wide-band optical coupling isolation amplifier for the Joint TEXT tokamak. FUSION ENGINEERING AND DESIGN 2015. [DOI: 10.1016/j.fusengdes.2015.06.122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Xiao JS, Yang ZJ, Liu MH, Zhuang G, Pan XM, Zhang C, Wang ZJ. A Supersonic Molecular Beam Injection System on the J-TEXT Tokamak. JOURNAL OF FUSION ENERGY 2015. [DOI: 10.1007/s10894-015-9918-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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31
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Chen W, Zhuang G, Gao L, Gentle KW, Chen J, Shi P, Liu Y, Li Q, Wang ZJ. Density modulation experiment to determine transport coefficients on Joint-TEXT Tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:023507. [PMID: 25725842 DOI: 10.1063/1.4906075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Density modulation experiments have been conducted on Joint-TEXT (J-TEXT) Tokamak Ohmic discharge to investigate particle transport based on a model with constant diffusion plus inward convection. Like the HCN interferometer, the newly developed three-wave polarimeter-interferometer system (POLARIS) is used to measure the perturbed density. The comparison of results between the HCN interferometer and POLARIS is given. The consistent results indicate the validity of the analysis scheme. At lower densities, the typical particle confinement time τp is found to increase with electron density, while it saturates at higher densities.
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Yan W, Chen ZY, Jin W, Huang DW, Ding YH, Li JC, Zhang XQ, Lee SG, Shi YJ, Zhuang G. Wavelength calibration of x-ray imaging crystal spectrometer on Joint Texas Experimental Tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11E416. [PMID: 25430323 DOI: 10.1063/1.4891058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The wavelength calibration of x-ray imaging crystal spectrometer is a key issue for the measurements of plasma rotation. For the lack of available standard radiation source near 3.95 Å and there is no other diagnostics to measure the core rotation for inter-calibration, an indirect method by using tokamak plasma itself has been applied on joint Texas experimental tokamak. It is found that the core toroidal rotation velocity is not zero during locked mode phase. This is consistent with the observation of small oscillations on soft x-ray signals and electron cyclotron emission during locked-mode phase.
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Chi Y, Zhuang G, Cheng ZF, Hou SY, Cheng C, Li Z, Wang JR, Wang ZJ. Design of charge exchange recombination spectroscopy for the joint Texas experimental tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11E421. [PMID: 25430328 DOI: 10.1063/1.4891705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The old diagnostic neutral beam injector first operated at the University of Texas at Austin is ready for rejoining the joint Texas experimental tokamak (J-TEXT). A new set of high voltage power supplies has been equipped and there is no limitation for beam modulation or beam pulse duration henceforth. Based on the spectra of fully striped impurity ions induced by the diagnostic beam the design work for toroidal charge exchange recombination spectroscopy (CXRS) system is presented. The 529 nm carbon VI (n = 8 - 7 transition) line seems to be the best choice for ion temperature and plasma rotation measurements and the considered hardware is listed. The design work of the toroidal CXRS system is guided by essential simulation of expected spectral results under the J-TEXT tokamak operation conditions.
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Huang DW, Chen ZY, Luo YH, Tong RH, Yan W, Jin W, Zhuang G. Hard X-ray spatial array diagnostics on Joint Texas Experimental Tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11D845. [PMID: 25430258 DOI: 10.1063/1.4891709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A spatially distributed hard X-ray detection array has been developed to diagnose the loss of runaway electron with toroidal and poloidal resolution. The hard X-ray radiation in the energy ranges of 0.3-1 MeV resulted from runaway electrons can be measured. The detection array consists of 12 CdTe detectors which are arranged surrounding the tokamak. It is found that most runaway electrons which transport to plasma boundary tend to loss on limiters. The application of electrode biasing probe resulted in enhancement of local runaway loss. Resonant magnetic perturbations enhanced the runaway electrons diffusion and showed an asymmetric poloidal loss rate.
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Cheng ZF, Luo J, Wang ZJ, Zhang ZP, Zhang XL, Hou SY, Cheng C, Li Z, Zhuang G. Edge impurity rotation profile measurement by using high-resolution ultraviolet/visible spectrometer on J-TEXT. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11E423. [PMID: 25430330 DOI: 10.1063/1.4891927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An upgrade of the edge rotation diagnostic system is achieved by increasing the number of viewing channels to 17 on J-TEXT tokamak. With the upgrade, the spatial resolution reaches 1 cm. The bulk plasma is used as the calibration light source. And the toroidal velocity profile of C V (carbon V) at edge region is obtained by using a spatial deconvolution technique. The valid measurement region is at ρ = 0.6-0.9, corresponding to the emitting region of C V. The preliminary experimental results express that the velocity of plasma may have a zero point near ρ = 0.85.
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Luo J, Zhuang G, Cheng ZF, Zhang XL, Hou SY, Cheng C. Improvement of the edge rotation diagnostic spectrum analysis via simulation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11E427. [PMID: 25430334 DOI: 10.1063/1.4892898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The edge rotation diagnostic (ERD) system has been developed on the Joint Texas Experimental Tokamak to measure the edge toroidal rotation velocity by observing the shifted wavelength of carbon V (C V 227.09 nm). Since the measured spectrum is an integrated result along the viewing line from the plasma core to the edge, a method via simulation has been developed to analyze the ERD spectrum. With the necessary parameters such as C V radiation profile and the ion temperature profile, a local rotation profile at the normalized minor radius of 0.5-1 is obtained.
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Zhang XL, Cheng ZF, Hou SY, Zhuang G, Luo J. Upgrade of absolute extreme ultraviolet diagnostic on J-TEXT. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11E420. [PMID: 25430327 DOI: 10.1063/1.4891159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The absolute extreme ultraviolet (AXUV) diagnostic system is used for radiation observation on J-TEXT tokamak [J. Zhang, G. Zhuang, Z. J. Wang, Y. H. Ding, X. Q. Zhang, and Y. J. Tang, Rev. Sci. Instrum. 81, 073509 (2010)]. The upgrade of the AXUV system is aimed to improve the spatial resolution and provide a three-dimensional image on J-TEXT. The new system consists of 12 AXUV arrays (4 AXUV16ELG arrays, 8 AXUV20ELG arrays). The spatial resolution in the cross-section is 21 mm for the AXUV16ELG arrays and 17 mm for the AXUV20ELG arrays. The pre-amplifier is also upgraded for a higher signal to noise ratio. By upgrading the AXUV imaging system, a more accurate observation on the radiation information is obtained.
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Chen J, Zhuang G, Li Q, Liu Y, Gao L, Zhou YN, Jian X, Xiong CY, Wang ZJ, Brower DL, Ding WX. High resolution polarimeter-interferometer system for fast equilibrium dynamics and MHD instability studies on Joint-TEXT tokamak (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11D303. [PMID: 25430163 DOI: 10.1063/1.4891603] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A high-performance Faraday-effect polarimeter-interferometer system has been developed for the J-TEXT tokamak. This system has time response up to 1 μs, phase resolution < 0.1° and minimum spatial resolution ∼15 mm. High resolution permits investigation of fast equilibrium dynamics as well as magnetic and density perturbations associated with intrinsic Magneto-Hydro-Dynamic (MHD) instabilities and external coil-induced Resonant Magnetic Perturbations (RMP). The 3-wave technique, in which the line-integrated Faraday angle and electron density are measured simultaneously by three laser beams with specific polarizations and frequency offsets, is used. In order to achieve optimum resolution, three frequency-stabilized HCOOH lasers (694 GHz, >35 mW per cavity) and sensitive Planar Schottky Diode mixers are used, providing stable intermediate-frequency signals (0.5-3 MHz) with S/N > 50. The collinear R- and L-wave probe beams, which propagate through the plasma poloidal cross section (a = 0.25-0.27 m) vertically, are expanded using parabolic mirrors to cover the entire plasma column. Sources of systematic errors, e.g., stemming from mechanical vibration, beam non-collinearity, and beam polarization distortion are individually examined and minimized to ensure measurement accuracy. Simultaneous density and Faraday measurements have been successfully achieved for 14 chords. Based on measurements, temporal evolution of safety factor profile, current density profile, and electron density profile are resolved. Core magnetic and density perturbations associated with MHD tearing instabilities are clearly detected. Effects of non-axisymmetric 3D RMP in ohmically heated plasmas are directly observed by polarimetry for the first time.
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Yi B, Rao B, Ding YH, Li M, Xu HY, Zhang M, Zhuang G, Pan Y. A novel method to optimize the mode spectrum of the dynamic resonant magnetic perturbation on the J-TEXT tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:113501. [PMID: 25430110 DOI: 10.1063/1.4901092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The dynamic resonant magnetic perturbation (DRMP) system has been developed for the J-TEXT tokamak to study the interaction between the rotating perturbation magnetic field and the plasma. When the DRMP coils are energized by two phase sinusoidal currents with the same frequency, a 2/1 rotating resonant magnetic perturbation component will be generated. But at the same time, a small perturbation component rotating in the opposite direction is also produced because of the control error of the currents. This small component has bad influence on the experiment investigations. Actually, the mode spectrum of the generated DRMP can be optimized with an accurate control of phase difference between the two currents. In this paper, a new phase control method based on a novel all-digital phase-locked loop (ADPLL) is proposed. The proposed method features accurate phase control and flexible phase adjustment. Modeling and analysis of the proposed ADPLL is presented to guide the design of the parameters of the phase controller in order to obtain a better performance. Testing results verify the effectiveness of the ADPLL and validity of the method applying to the DRMP system.
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Zhu Y, Zhao Z, Liu WD, Xie J, Hu X, Muscatello CM, Domier CW, Luhmann NC, Chen M, Ren X, Tobias BJ, Zhuang G, Yang Z. Optics design for J-TEXT ECE imaging with field curvature adjustment lens. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11D854. [PMID: 25430267 DOI: 10.1063/1.4893352] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Significant progress has been made in the imaging and visualization of magnetohydrodynamic and microturbulence phenomena in magnetic fusion plasmas. Of particular importance has been microwave electron cyclotron emission imaging (ECEI) for imaging Te fluctuations. Key to the success of ECEI is a large Gaussian optics system constituting a major portion of the focusing of the microwave radiation from the plasma to the detector array. Both the spatial resolution and observation range are dependent upon the imaging optics system performance. In particular, it is critical that the field curvature on the image plane is reduced to decrease crosstalk between vertical channels. The receiver optics systems for two ECEI on the J-TEXT device have been designed to ameliorate these problems and provide good performance with additional field curvature adjustment lenses with a meniscus shape to correct the aberrations from several spherical surfaces.
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Chen J, Zhuang G, Jian X, Li Q, Liu Y, Gao L, Wang ZJ. Equilibrium reconstruction based on core magnetic measurement and its applications on equilibrium transition in Joint-TEXT tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:103501. [PMID: 25362387 DOI: 10.1063/1.4896476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Evaluation and reconstruction of plasma equilibrium, especially to resolve the safety factor profile, is imperative for advanced tokamak operation and physics study. Based on core magnetic measurement by the high resolution laser polarimeter-interferometer system (POLARIS), the equilibrium of Joint-TEXT (J-TEXT) plasma is reconstructed and profiles of safety factor, current density, and electron density are, therefore, obtained with high accuracy and temporal resolution. The equilibrium reconstruction procedure determines the equilibrium flux surfaces essentially from the data of POLARIS. Refraction of laser probe beam, a major error source of the reconstruction, has been considered and corrected, which leads to improvement of accuracy more than 10%. The error of reconstruction has been systematically assessed with consideration of realistic diagnostic performance and scrape-off layer region of plasma, and its accuracy has been verified. Fast equilibrium transitions both within a single sawtooth cycle and during the penetration of resonant magnetic perturbation have been investigated.
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Luo YH, Chen ZY, Tang Y, Wang SY, Ba WG, Wei YN, Ma TK, Huang DW, Tong RH, Yan W, Geng P, Shao J, Zhuang G. Designing of the massive gas injection valve for the joint Texas experimental tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:083504. [PMID: 25173266 DOI: 10.1063/1.4891864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In order to mitigate the negative effects of the plasma disruption a massive gas injection (MGI) valve is designed for the joint Texas experimental tokamak. The MGI valve is based on the eddy-current repulsion mechanism. It has a fueling volume of 30 ml. The piston of the MGI valve is made by non-ferromagnetic material, so it can be installed close to the vacuum vessel which has a strong toroidal magnetic field. A diode is use to prevent current oscillation in the discharge circuit. The drive coil of the valve is installed outside the gas chamber. The opening characteristics and the gas flow of the MGI valve have been tested by a 60 l vacuum chamber. Owing to the large electromagnetic force the reaction time of the valve is shorter than 0.3 ms. Duration for the opening of the MGI valve is in the order of 10 ms.
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Yin X, Zheng W, Zhang M, Zhang J, Zhuang G, Ding T. A modularized operator interface framework for Tokamak based on MVC design pattern. FUSION ENGINEERING AND DESIGN 2014. [DOI: 10.1016/j.fusengdes.2014.03.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Zhu TZ, Chen ZP, Sun Y, Nan JY, Liu H, Zhuang G, Wang ZJ. The construction of an electrode biasing system for driving plasma rotation in J-TEXT tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:053504. [PMID: 24880366 DOI: 10.1063/1.4873320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A newly designed electrode biasing system has been constructed for driving plasma rotation in J-TEXT tokamak. To reduce the influence to the plasma, the system contains a pneumatic driving system so that it can reciprocate in a single discharge, with a stroke of about 5 cm in 100 ms. The power supply of the system can provide stable and adjustable dc voltage in the range of 0-700 V, with adjustable duration of 10-200 ms; its instantaneous power output can reach up to more than 200 kW. In addition, the power supply can also provide a multi-cycle voltage waveform, with adjustable pulse width and voltage amplitude. When applying a positive bias to the plasma, both an improvement of plasma confinement and the speed-up of plasma-edge toroidal rotation in the same direction of plasma current are observed in the experiments.
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Tan H, Zhang M, Rao B, Yang Y, Ding YH, Zhuang G. Toroidal Field Analysis of the J-TEXT Tokamak. FUSION SCIENCE AND TECHNOLOGY 2014. [DOI: 10.13182/fst13-715] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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46
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Zhang J, Zhang M, Zheng W, Zhuang G, Ding T. Design and application of an EPICS compatible slow plant system controller in J-TEXT tokamak. FUSION ENGINEERING AND DESIGN 2014. [DOI: 10.1016/j.fusengdes.2014.04.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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47
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Zheng W, Liu R, Zhang M, Zhuang G, Yuan T. Design of FPGA based high-speed data acquisition and real-time data processing system on J-TEXT tokamak. FUSION ENGINEERING AND DESIGN 2014. [DOI: 10.1016/j.fusengdes.2014.01.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Rao B, Wang G, Ding Y, Yu K, Li Q, Wang N, Yi B, Nan J, Cen Y, Hu Q, Jin W, Li J, Jin H, Zhang M, Zhuang G. Introduction to resonant magnetic perturbation coils of the J-TEXT Tokamak. FUSION ENGINEERING AND DESIGN 2014. [DOI: 10.1016/j.fusengdes.2014.03.038] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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49
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Ding YH, Wang NC, Rao B, Jin XS, Chen ZP, Hu QM, Jin H, Jin W, Li JC, Xie SJ, Yi B, Zhuang G, Pan Y. Analytical compensation of axisymmetric equilibrium fluxes picked up by locked mode detectors in tokamaks. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:043502. [PMID: 24784602 DOI: 10.1063/1.4870416] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the detection of locked modes using saddle loops, the problem of how to remove the axisymmetric equilibrium flux picked up by the loops has still to be solved. The problem becomes more difficult when there are conductive structures located near the saddle loops. In this paper, we present an analytical model based on lumped eddy current circuits and use it to interpret the measured equilibrium flux and the corresponding eddy current fluxes. Using this model, precise compensation for fluxes induced by the horizontal field coils and the toroidal field coils, with relative errors of less than 1%, has been realized for the saddle loops in the Joint Texas Experimental Tokamak. This paper also presents a new method to compensate for the detection of equilibrium flux by the locked mode detector.
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Jin W, Chen ZY, Huang DW, Li QL, Yan W, Luo YH, Lee SG, Shi YJ, Huang YH, Tong RH, Yang ZJ, Rao B, Ding YH, Zhuang G. Upgraded high time-resolved x-ray imaging crystal spectroscopy system for J-TEXT ohmic plasmas. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:023509. [PMID: 24593363 DOI: 10.1063/1.4864147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This paper presents the upgraded x-ray imaging crystal spectrometer (XICS) system on Joint Texas Experimental Tokamak (J-TEXT) tokamak and the latest experimental results obtained in last campaign. With 500 Hz frame rate of the new Pilatus detector and 5 cm × 10 cm spherically bent crystal, the XICS system can provide core electron temperature (Te), core ion temperature (Ti), and plasma toroidal rotation (VΦ) with a maximum temporal resolution of 2 ms for J-TEXT pure ohmic plasmas. These parameters with high temporal resolution are very useful in tokamak plasma research, especially for rapidly changed physical processes. The experimental results from the upgraded XICS system are presented.
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