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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU Zai-ming GENG bing-zhen WANG shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily *** some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite *** we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Geant4 simulation of fast-electron bremsstrahlung imaging at the HL-3 tokamak

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Nuclear Science and Techniques 2024年第9期35卷 213-229页

作者： shi-Kui Cheng Yi-Po Zhang Yue-Jiang shi jie Zhang Shuai Guan Hong-bing Xu Qiu-Lei Yang College of Science Chongqing University of TechnologyChongqing 400054China Chongqing Key Laboratory of New Energy Storage Materials and Devices Chongqing 400054China Southwestern Institute of Physics Chengdu 610041China Hebei Key Laboratory of Compact Fusion Langfang 065001China ENN Science and Technology Development Co. Ltd.Langfang 065001China

To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 *** application of an array-structured detector ensures that this system can measure HXR-radiation spectra from the entire plasma cross ***,it is suitable for the study of fast-electron physics,such as radio-frequency wave current drives,fast electrons driving instabilities,and plasma disruptions in fusion *** this study,we develop a simulation for calculating fast-electron bremsstrahlung in the HL-3 tokamak based on the Monte Carlo simulation code Geant4,in which the plasma geometry and forward scattering of fast-electron bremsstrahlung are *** preliminary calculation results indicate that the HXR energy deposi-tion on the detector is symmetrically distributed,even though the plasma distribution is asymmetric owing to the toroidal *** simulation results are helpful in constructing the relationship between the energy deposition on the detector and parameter distribution on the plasma cross section during HL-3 *** is beneficial for the reconstruction of the fast-electron-distribution function and for optimizing the design of the HXR-imaging system.

关键词： Geant4 simulation HL-3 tokamak Fast-electron bremsstrahlung Hard X-ray imaging

Effect of electrical parameters and slag system on macrostructure of electroslag ingot

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China Foundry 2024年第1期21卷 44-50页

作者： bing-jie Wang Yu Wang Meng-jun Wang Lei Zhao Li-zhong Chang Xiao-fang shi School of Metallurgy engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting,different power supply modes,current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 304L austenitic stainless steel,and the macrostructure of electroslag ingots was *** results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply *** effects of different power supply modes,such as low-frequency,direct current straight polarity(DCSP),and direct current reverse polarity(DCRP),on reducing the depth of the metal pool increase in that *** reducing the remelting current strength in the same power supply mode,the depth of metal pool is *** compared to the binary slag system of 70%CaF2+30%Al2O3,the ternary slag system of 60%CaF2+20%Al2O3+20%CaO is more effective in reducing the depth of the metal pool during *** the 60%CaF2+20%Al2O3+20%CaO ternary slag system results in a shallower and flatter metal pool,with columnar crystal growth occurring closer to the axial *** effect is observed for both low frequency and direct current(DC)power supply modes.

关键词： electroslag remelting frequency slag system solidification quality

Intraorbital wooden foreign bodies: case series and literature review

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International Journal of Ophthalmology(English edition) 2021年第10期14卷 1619-1627页

作者： Ya-Yan You bing-jie shi Xin-Yan Wang Jin Chen Zheng-Rong Wang Xing-Hua Wang Fa-Gang Jiang Department of Ophthalmology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

Intraorbital wooden foreign bodies(IOWFBs) constitute a relatively rare ocular trauma, which occupy a special type of intraorbital foreign bodies(IOFBs). Data regarding IOWFBs must be obtained from case reports or small case series due to their rarity. Here, we reported 5 cases of IOWFBs and reviewed the related literatures, which could provide comprehensive information regarding the clinical manifestations, diagnosis, and surgical treatment of IOWFBs. Combined with the published literature, a total of 51 independent cases were counted after we added 5 cases. Among them, the number of male and female patients was 35 and 16 respectively;the mean age was 27.3±18.2(range 1-66)y. Obviously, the disorder seemed to occur mainly in young and middle-aged people. Because of the diversity in the clinical manifestations and imaging characteristics of IOWFBs, misdiagnosis and missed diagnosis often occur during the initial visit. Delayed diagnosis may lead to a high risk of orbital infection caused by IOWFBs. Surgery is the treatment of choice for most patients;however, the missed diagnosis and residue of foreign bodies after previous surgery cannot be ignored. Therefore, an accurate diagnosis is governed by the detailed trauma history, careful ocular examination, close observation of clinical manifestations, correct imaging diagnosis [e.g., magnetic resonance imaging(MRI) or computerized tomography(CT)], and timely and completely elimination of IOWFBs.

关键词： orbit foreign body wooden trauma infection

Cooperative control for heterogeneous multi-agent systems: progress, applications, and challenges

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Science China(Information Sciences) 2024年第5期67卷 318-320页

作者： bing YAN Peng shi Jonathon CHAMBERS School of Electrical and Mechanical Engineering Faculty of Science Engineering and TechnologyThe University of Adelaide School of Engineering College of Science and Engineering University of Leicester

Cooperative control for heterogeneous multi-agent systems(MASs) is a critical and rapidly evolving field in modern automation and robotics. Characterized by the integration of agents with diverse capabilities and func... 详细信息

关键词： Multi agent systems

Projected changes in Köppen-Trewartha climate zones under 1.5-4℃global warming targets over mid-high latitudes of Northern Asia using an ensemble of RegCM4 simulations

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Advances in Climate Change Research 2024年第2期15卷 185-196页

作者： jie WU Xue-jie GAO Xian-bing TANG Filippo GIORGI School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China The Abdus Salam International Centre for Theoretical Physics Trieste 34100Italy

Mid-high latitude Northern Asia is one of the most vulnerable and sensitive areas to global warming,but relatively less studied *** used an ensemble of a regional climate model(RegCM4)projections to assess future changes in surface air temperature,precipitation and Köppen-Trewartha(K-T)climate types in Northern Asia under the 1.5-4℃global warming ***4 is driven by five CMIP5 global models over an East Asia domain at a grid spacing of 25 *** of the present day(1986-2005)simulations shows that the ensembles of RegCM4(ensR)and driving GCMs(ensG)reproduce the major characters of the observed temperature,precipitation and K-T climate zones reasonably *** and more realistic spatial detail is found in RegCM4 compared to the driving GCMs.A general warming and overall increases in precipitation are projected over the region,with these changes being more pronounced at higher warming *** projected warming by ensR shows different spatial patterns,and is in general lower,compared to ensG in most months of the year,while the percentage increases of precipitation are maximum during the cold *** future changes in K-T climate zones are characterized by a substantial expansion of Dc(temperature oceanic)and retreat of Ec(sub-arctic continental)over the region,reaching∼20%under the 4℃warming *** most notable change in climate types in ensR is found over Japan(∼60%),followed by Southern Siberia,Mongolia,and the Korean Peninsula(∼40%).The largest change in the K-T climate types is found when increasing from 2 to 3℃.The results will help to better assess the impacts of climate change and in implementation of appropriate adaptation measures over the region.

关键词： Mid-high latitudes of Northern Asia Köppen climate zones Global warming targets Regional climate model

Photo-Responsive Carbon Capture over Metalloporphyrin-C_(60) Metal-Organic Frameworks via Charge-Transfer

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Research 2024年第3期2023卷 233-241页

作者： shi-Chao Qi Zhen Sun Zhi-Hui Yang Yun-jie Zhao Jia-Xin Li Xiao-Qin Liu Lin-bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China.

Great efforts have been devoted to the study of photo-responsive adsorption,but its current methodology largely depends on the well-defined photochromic units and their photo-driven molecular ***,a methodology to fabricate nondeforming photo-responsive sorbents is successfully *** C_(60)-fullerene doping in metalloporphyrin metal-organic frameworks(PCN-M,M=Fe,Co,or Ni)and intensively interacting with the metalloporphyrin sites,effective charge-transfer can be achieved over the metalloporphyrin-C_(60) architectures once excited by the light at 350 to 780 *** electron density distribution and the resultant adsorption activity are thus changed by excited states,which are also stable enough to meet the timescale of microscopic adsorption *** charge-transfer over Co(II)-porphyrin-C_(60) is proved to be more efficient than the Fe(II)-and Ni(II)-porphyrin-C_(60) sites,as well as than all the metalloporphyrin sites,so the CO_(2) adsorption capacity(CAC;at 0°C and 1 bar)over the C_(60)-doped PCN-Co can be largely improved from 2.05 mmol g^(−1) in the darkness to 2.69 mmol g−1 with light,increased by 31%,in contrast to photo-irresponsive CAC over all C_(60)-undoped PCN-M sorbents and only the photo-loss CAC over C_(60).

关键词： porphyrin adsorption excited

Hierarchical multihead self-attention for time-series-based fault diagnosis

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Chinese Journal of Chemical Engineering 2024年第6期70卷 104-117页

作者： Chengtian Wang Hongbo shi bing Song Yang Tao Key Laboratory of Smart Manufacturing in Energy Chemical Process of the Ministry of Education East China University of Science and TechnologyShanghai 200237China

Fault diagnosis is important for maintaining the safety and effectiveness of chemical *** the multivariate,nonlinear,and dynamic characteristic of chemical process,many time-series-based data-driven fault diagnosis methods have been developed in recent ***,the existing methods have the problem of long-term dependency and are difficult to train due to the sequential way of *** overcome these problems,a novel fault diagnosis method based on time-series and the hierarchical multihead self-attention(HMSAN)is proposed for chemical ***,a sliding window strategy is adopted to construct the normalized time-series ***,the HMSAN is developed to extract the time-relevant features from the time-series process *** improves the basic self-attention model in both width and *** the multihead structure,the HMSAN can pay attention to different aspects of the complicated chemical process and obtain the global dynamic ***,the multiple heads in parallel lead to redundant information,which cannot improve the diagnosis *** the hierarchical structure,the redundant information is reduced and the deep local time-related features are further ***,a novel many-to-one training strategy is introduced for HMSAN to simplify the training procedure and capture the long-term ***,the effectiveness of the proposed method is demonstrated by two chemical *** experimental results show that the proposed method achieves a great performance on time-series industrial data and outperforms the state-of-the-art approaches.

关键词： Self-attention mechanism Deep learning Chemical process Time-series Fault diagnosis

Damping capacity of Fe_(83)Ga_(17) magnetostrictive alloy under magnetic field

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Rare Metals 2024年第1期43卷 402-409页

作者： Shao-Wen Yan Xing Mu bing-jie Liu Li-Hong Xu shi-Hai Guo Yan Qi Hong-Ping Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China

The damping performance of Fe_(83)Ga_(17) alloys has been investigated in the static magnetic field (H). The results demonstrate that the damping peak value can be adjusted between 0.020 and 0.085 under the magnetic f... 详细信息

关键词： alloy magnetic alloys

Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification

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Defence Technology（防务技术） 2024年第1期31卷 375-386页

作者： jie Zhao Zhongjiao shi Yuchen Wang Wei Wang Beijing Institute of Technology Beijing 100081China

This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system ***,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference ***,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F ***,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression *** long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be ***,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations.

关键词： Rotor-missile Adaptive control Parameter identification Quaternion control