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Plasma Science and Technology 2024年第3期26卷 94-99页

作者：赵传旭李建超张晓卿王能超丁永华杨州军江中和严伟李杨波毛飞越任正康 the J-TEXT Team International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic Engineering and School of PhysicsHuazhong University of Science and TechnologyWuhan 430074People's Republic of China Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of TechnologyWuhan 430205People's Republic of China International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China

A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on *** T-SXRI system consists of three sets of SXR *** sets are newly developed and located on the vacuum chamber wall at toroidal positionsφof 126.4°and 272.6°,respectively,while one set was established previously atφ=*** set of SXR arrays consists of three arrays viewing the plasma poloidally,and hence can be used separately to obtain SXR images via the tomographic *** sawtooth precursor oscillations are measured by T-SXRI,and the corresponding images of perturbative SXR signals are successfully reconstructed at these three toroidal positions,hence providing measurement of the 3D structure of precursor *** observed 3D structure is consistent with the helical structure of the m/n=1/1 *** experimental observation confirms that the T-SXRI system is able to observe 3D structures in the J-TEXT plasma.

关键词： SXR imaging J-TEXT tokamak three-dimensional measurement MHD

Fast algorithms for Walsh transform in bit-reversed sequency order

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Chinese Science Bulletin 1998年第8期43卷 627-633页

作者： Qing Li Meilian Zhou Baochang Shi nengchao wang S Cent Univ Nationalities Dept Comp Sci Wuhan 430074 Peoples R China Huazhong Univ Sci & Technol Parallel Computat Res Inst Wuhan 430074 Peoples R China

Bit_reversed sequency order or bit_reversed Walsh order (M) is presented. Walsh functions in this order can be processed easily, and there is a simple relation between sequency order and bit_reversed sequency order. 8... 详细信息

关键词： bit-reversed sequency (bit-reversed Walsh) order Walsh functions fast algorithm bisection pattern.

Suppression of the m/n=2/1 tearing mode by electron cyclotron resonance heating on J-TEXT

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Plasma Science and Technology 2024年第8期26卷 8-17页

作者：方建港陈忠勇严伟王能超毛飞越罗蔷玄子健陈曦璇任正康张峰黄梅夏冬辉杨州军陈志鹏丁永华 the J-TEXT Team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China Southwestern Institute of Physics Chengdu 610041People’s Republic of China

Stabilization of tearing modes and neoclassical tearing modes is of great importance for tokamak *** cyclotron waves(ECWs)have been extensively used to stabilize the tearing modes with the virtue of highly localized power *** suppression of the m/n=2/1 tearing mode(TM)by electron cyclotron resonance heating(ECRH)has been achieved successfully on the J-TEXT *** effects of ECW deposition location and power amplitude on the 2/1 TM suppression have been *** is found that the suppression is more effective when the ECW power is deposited closer to the rational *** the ECW power increases to approximately 230 k W,the 2/1 TM can be completely *** island rotation frequency is increased when the island width is *** experimental results show that the local heating inside the magnetic island and the resulting temperature perturbation increase at the O-point of the island play dominant roles in TM *** the ECW power increases,the 2/1 island is suppressed to smaller island width,and the flow shear also plays a stabilizing effect on small magnetic *** the stabilizing contribution of heating and flow shear,the 2/1 TM can be completely suppressed.

关键词： tearing mode electron cyclotron resonant heating tearing mode suppression

Digital Watermarking Algorithm Based on Wavelet Transform and Neural Network

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1667-1670页

作者： wang Zhenfei ZHAI Guangqun wang nengchao College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China College of Information Engineering Zhengzhou University Zhengzhou 450001 Henan China

An effective blind digital watermarking algorithm based on neural networks in the wavelet domain is presented. Firstly, the host image is decomposed through wavelet transform. The significant coefficients of wavelet are selected according to the human visual system （HVS） characteristics. Watermark bits are added to them. And then effectively cooperates neural networks to learn the characteristics of the embedded watermark related to them. Because of the learning and adaptive capabilities of neural networks, the trained neural networks almost exactly recover the watermark from the watermarked image. Experimental results and comparisons with other techniques prove the effectiveness of the new algorithm.

关键词： digital watermarking neural networks wavelet transform human visual system

A brief review of the development and optimization of the three-dimensional magnetic configuration system in the J-TEXT tokamak

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Plasma Science and Technology 2022年第12期24卷 166-171页

作者： Zhonghe JIANG Yonghua DING Bo RAO nengchao wang Yangbo LI Jie HUANG International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics(IFPP) State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China Forschungszentrum Jülich GmbH Institut für Energie-und Klimaforschung-PlasmaphysikJülich 52425Germany

The three-dimensional(3D) magnetic configuration system in the J-TEXT tokamak has featured in many experimental *** system mainly consists of three subsystems:the static resonant magnetic perturbation(SRMP) system,the dynamic resonant magnetic perturbation(DRMP) system and the helical coil *** SRMP coil system consist of two kinds of coils,*** six-loop coils and two five-loop *** can suppress tearing modes with a moderate strength,and may also cause mode locking with larger *** DRMP coil system consists of 12 single-turn saddle coils(DRMP1) and 12 double-turn saddle coils(DRMP2).Its magnetic field can be rotated at a few kHz,leading to either acceleration or deceleration of the tearing mode velocity and the plasma *** helical coil system consists of two closed coils,and is currently under construction to provide external rotational transform in *** 3D magnetic configuration system can suppress tearing modes,preventing and avoiding the occurrence of major disruption.

关键词： tearing mode resonant magnetic perturbation external rotational transform plasma stability J-TEXT tokamak

Characteristics of the SOL ion-to-electron temperature ratio on the J-TEXT tokamak with different plasma configurations

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Plasma Science and Technology 2024年第2期26卷 13-21页

作者：李存凯梁云峰江中和周松华建坤阳杰杨庆虎 Alexander KNIEPS Philipp DREWS 徐鑫毛飞越谢伟杨雨桐郭金龙李杨波任正康陈志鹏王能超 the J-TEXT Team International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China Forschungszentrum Jülich GmbH Institut für Energie-und Klimaforschung—PlasmaphysikPartner of the Trilateral Euregio Cluster(TEC)Julich 52425Germany 不详

Accurate measurement of the average plasma parameters in the edge region,including the temperature and density of electrons and ions,is critical for understanding the characteristics of the scrape-off layer(SOL) and divertor plasma transport in magnetically confined fusion *** the J-TEXT tokamak,a multi-channel retarding field analyzer(RFA) probe has been developed to study average plasma parameters in the edge region under various poloidal divertor and island divertor *** edge radial profile of the ion-to-electron temperature ratio,τ_(i/e),has been determined,which gradually decreases as the SOL ion self-collisionality,v_(SOL)*,*** is broadly consistent with what has been observed previously from various tokamak ***,the comparison of experimental results under different configurations shows that in the poloidal divertor configuration,even under the same v_(SOL)*,τ_(i/e) in the SOL region becomes smaller as the distance from the X-point to the target plate *** the island divertor configuration,τ_(i/e) near the O-point is higher than that near the X-point at the same v_(SOL)*,and both are higher than those in the limiter *** results suggest that the magnetic configuration plays a critical role in the energy distributions between electrons and ions at the plasma boundary.

关键词： ion temperature island divertor poloidal divertor retarding field analyzer(RFA)probe

Catalyst design and structure control for photocatalytic refineries of cellulosic biomass to fuels and chemicals

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Journal of Energy Chemistry 2024年第7期94卷 102-127页

作者： Lulu Sun nengchao Luo State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Lignocellulosic biomass is the largest renewable hydrocarbon resource on *** cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footprint energy chemicals such as H_(2),HCOOH,CO,and transportation ***-of-the-art biorefineries target the full use of biomass feedstocks as they have a maximum collection radius of 75-100 km,requesting efficient and selective photocatalysts that significantly influence the outcome of photocatalytic ***-performed photocatalysts can harvest a broad solar spectrum and are active in breaking the chemical bonds of cellulose,decreasing the capital investments of ***,photocatalysts should control the selectivity of cellulose conversion,originating target products to level down separation *** separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous *** account for the challenges above,this review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products,with the structure features of different types of photocatalysts discussed in relation to the targets of either improving the activity or product *** addition,this review also sheds light on the methods for designing and regulating photocatalyst structures to facilitate photocatalytic refineries of cellulose and platform molecules,meanwhile summarizing proposed future research challenges and opportunities for designing efficient photocatalysts.

关键词： Photocatalysts Biorefineries Cellulose Fuels Hydrogen

Magnetic diagnostics for magnetohydrodynamic instability research and the detection of locked modes in J-TEXT

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Plasma Science and Technology 2021年第5期23卷 49-58页

作者： Dongliang HAN Chengshuo SHEN nengchao wang Da LI Feiyue MAO Zhengkang REN Yonghua DING the J-TEXT Team International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China

Magnetohydrodynamic(MHD)instabilities are widely observed during tokamak plasma *** diagnostics provide important information which supports the understanding and control of MHD *** paper presents the current status of the magnetic diagnostics dedicated to measuring MHD instabilities at the J-TEXT tokamak;the diagnostics consist of five Mirnov probe arrays for measuring high-frequency magnetic perturbations and two saddle-loop arrays for low-frequency magnetic perturbations,such as the locked *** recent years,several changes have been made to these *** structure of the probes in the poloidal Mirnov arrays has been optimized to improve their mechanical strength,and the number of in-vessel saddle loops has also been improved to support better spatial *** to the installation of high-field-side(HFS)divertor targets in early 2019,some of the probes were removed,but an HFS Mirnov array was designed and installed behind the *** to its excellent toroidal symmetry,the HFS Mirnov array has,for the first time at J-TEXT,provided valuable new information about the locked mode and the quasi-static mode(QSM)in the ***,various groups of magnetic diagnostics at different poloidal locations have been systematically used to measure the QSM,which confirmed the poloidal mode number m and the helical structure of the *** including the HFS information,the 2/1 resonant magnetic perturbation(RMP)-induced locked mode was measured to have a poloidal mode number m of~2.

关键词： J-TEXT tokamak locked mode magnetic diagnostics magnetohydrodynamic instabilities

Spiral waves in CIMA model and its LBGK simulation

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Communications in Nonlinear Science and Numerical Simulation 2001年第2期6卷 68-73页

作者： Qing LI, Chuguang ZHENG and nengchao wang College of Computer Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China e-mail: qingli @ public. *** State Key Laboratory of Coal Combustion, Huazhong University College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China Parallel Computation Institute Huazhong University of Science and Technology Wuhan 430074 China

Two type of structures-Turing patterns and spiral waves-are obtained in chloride-iodide-malonic acid (CIMA) reaction-diffusion model by using lattice Bhatnagar-Gross-Krook (LBGK) method.

关键词： lattice Boltzmann method reaction-diffusion Turing patterns spiral waves

TWO NEW FCT ALGORITHMS BASED ON PRODUCT SYSTEM

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Analysis in Theory and Applications 2001年第3期17卷 33-42页

作者： Guo Zhaoli Shi Baochang wang nengchao National Laboratory of Coal Combustion Wuhan 430074P R China Department of Mathematics Hauzhong University of Science and TechnologyWuhan 430074PR China

In this paper we present a product system and give a representation for consine functions with the system. Based on the formula two new algorithms are designed for computing the Discrete Cosine Transform. Both algorit... 详细信息

关键词： Discrete Cosine Transform Digital Signal Processing Recursive Algorithm numerical stability Error Analysis New Algorithm Methods for