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Superjunction 4H-SiC trench-gate IGBT with an integrated clamping PN diode

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 3-9,27页

作者： Huang yi Wang Xuecheng Gao Sheng Liu Bin Zhang Hongsheng han Genquan School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic Science and Engineering Nanjing UniversityNanjing 210008China School of Microelectronics Xidian UniversityXi'an 710126China

In this paper,a novel superjunction 4H-silicon carbide(4H-SiC)trench-gate insulated-gate bipolar transistor(IGBT)featuring an integrated clamping PN diode between the P-shield and emitter(TSD-IGBT)is designed and theoretically *** heavily doping superjunction layer contributes to a low specific on-resistance,excellent electric field distribution,and quasi-unipolar drift *** anode of the clamping diode is in floating contact with the *** the on-state,the potential of the P-shield is raised to the turn-on voltage of the clamping diode,which prevents the hole extraction below the N-type carrier storage layer(NCSL).Additionally,during the turn-off transient,once the clamping diode is turned on,it also promotes an additional hole extraction ***,the potential dropped at the semiconductor near the trench-gate oxide is effectively reduced in the off-state.

关键词： 4H-silicon carbide(4H-SiC) trench-gate superjunction clamping diode

Cretaceous-Neogene Exhumation of the Daqing Shan,North China Constrained by Apatite Fission Track Thermochronology

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Journal of Earth Science 2024年第1期35卷 99-111页

作者： Junlin Zhou Yuhong Li wei han Yunpeng Zhang Gaochao Chen Qiao Zhang Jianshe wei Yazhuo Niu Xi'an Center of China Geological Survey Xi an 710054China Northwest China Center for Center Geoscience Innovation Xi'an 710054China

The Daqing Shan(DQS)located in the yinshan-Yanshan Orogenic Belt plays an important role in the Mesozoic to Cenozoic evolution of the North China ***,the cooling and exhumation history since the Cretaceous is still *** the apatite fission track(AFT)data in both this study and previous works,a three-stage exhumation history from Cretaceous to Neogene of the DQS is proposed.(1)The first stage is composed of the early exhumation during Early Cretaceous driven by the collision between the North China and Siberia cratons(ca.148-132 Ma)and the far-field effect of the subduction of the Pacific Plate(ca.132-114 Ma).(2)Due to the subsidence of the Hetao Basin and the subsequent compensation between the DQS and the Hetao Basin,the DQS experienced the second rapid exhumation from Early Eocene to Early Oligocene(ca.54-29 Ma).(3)Since the Late Miocene(ca.13.5 Ma),the third rapid cooling and exhumation of the DQS occurred due to the far-field effect of the uplift of the Tibetan Plateau and the subduction of the Pacific Plate.

关键词： Daqing Shan Hetao Basin Cretaceous-Neogene apatite geochronology apatite fission track cooling and exhumation

All-sky Guide Star Catalog for CSST

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Research in Astronomy and Astrophysics 2024年第4期24卷 35-59页

作者： Hui-Mei Feng Zi-Huang Cao Man I Lam Ran Li Hao Tian Da-yi yin Yuan-Yu Yang Xin Zhang Dong-wei Fan yi-Qiao Dong Xin-Feng Li wei Wang Long Li Hugh RAJones yi-han Tao Jia-Lu Nie Pei-Pei Wang Mao-Yuan Liu He-jun Yang Chao Liu Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of ChineseAcademy of Sciences Beijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai200083China Technology and Engineering Center for Space Utilization.Chinese Academy of Sciences Beijing 100094China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Centre for Astrophysics University of HertfordshireHatfieldUK Beijing University of Technology Beijing 100124China

The China Space Station Telescope(CSST)is a two-meter space telescope with multiple back-end *** Fine Guidance Sensor(FGS)is an essential subsystem of the CSST Precision Image Stability System to ensure the required absolute pointing accuracy and line-of-sight *** this study,we construct the Main Guide Star Catalog for *** accomplish this,we utilize the information about the FGS and object information from the Gaia Data Release *** provide an FGS instrument magnitude and exclude variables,binaries,and high proper motion stars from the catalog to ensure uniform FGS guidance ***,we generate a HEALPix index,which provides a hierarchical tessellation of the celestial sphere,and employ the Voronoi algorithm to achieve a homogeneous distribution of stars across the *** distribution ensures adequate coverage and sampling of the *** performance of the CSST guide star catalog was assessed by simulating the field of view of the FGS according to the CSST mock survey strategy *** analysis of the results indicates that this catalog provides adequate coverage and *** catalog's performance meets the FGS requirements,ensuring the functioning of the FGS and its guidance capabilities.

关键词： catalogs astrometry instrumentation:detectors

To improve robustness of mechanical properties of semi-solid cast A356 alloy using taguchi design method

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China Foundry 2024年第2期21卷 175-184页

作者： yi-wu Xu Hong-yi Zhan wei Tong Jin-ping Li Le-peng Zhang De-jiang Li Xiao-qin Zeng School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China China Science Lab General Motors Global Research&DevelopmentShanghai 201206China General Motors(China)Investment Co. Ltd.Shanghai 201206China China International Intellectech Corporation(CIIC) Beijing 100004China

Mechanical properties of semi-solid casting are dependent on multiple processing parameters,and improper processing parameters will not only reduce mean data but also increase *** present study investigated the impact of parameters in slurry preparation and heat treatment on the yield strength and ductility of T6 heat-treated A356 Al-Si alloy using rapid slurry forming(RSF)semi-solid *** focus was primarily on the robustness of mechanical properties based on Taguchi design *** analyzing signal-to-noise ratio and minimum value calculated from-3S,the optimum slurry preparation parameters and heat treatment parameters were determined to be no quench,enthalpy exchange material(EEM)temperature of 140℃,EEM-to-melt ratio of 6mass%,stirring time of 18 s,solution heat treated at 520℃ for 2 h,and ageing heat treated at 190℃ for 6 *** a small batch validation,the-3S yield strength and-3S elongation reach 256.1 MPa and 5.03% respectively,showing a satisfactory *** hardness and microstructure of heat-treated samples with the best and worst properties were characterized to gain insight into the underlying mechanisms affecting the mean value and variations of mechanical properties.

关键词： semi-solid casting taguchi design method signal-to-noise ratio mechanical property microstructure

New insights into the deposition of natural gas hydrate on pipeline surfaces:A molecular dynamics simulation study

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Petroleum Science 2024年第1期21卷 694-704页

作者： Jun Zhang Hai-Qiang Fu Mu-Zhi Guo Zhao Wang Li-Wen Li Qi yin You-Guo Yan wei wei wei-Feng han Jie Zhong School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina Department of Alternative Energy PetroChina Research Institute of Petroleum Exploration&DevelopmentLangfang 065007HebeiChina

Natural gas hydrate(NGH)can cause pipeline blockages during the transportation of oil and gas under high pressures and low *** hydrate adhesion on pipelines is viewed as an efficient way to prevent NGH *** studies suggested the water film can greatly increase hydrate adhesion in gas-dominant ***,by performing the molecular dynamics simulations,we find in water-dominant system,the water film plays different roles in hydrate deposition on Fe and its corrosion ***,due to the strong affinity of water on Fe surface,the deposited hydrate cannot convert the adsorbed water into hydrate,thus,a water film *** water affinities decrease(Fe>Fe_(2)O_(3)>FeO>Fe_(3)O_(4)),adsorbed water would convert to amorphous hydrate on Fe_(2)O_(3)and form the ordered hydrate on FeO and Fe_(3)O_(4)after hydrate *** absorbed water film converts to amorphous or to hydrate,the adhesion strength of hydrate continuously increases(Fehanisms on Fe and its corrosion surfaces and suggest hydrate deposition can be adjusted by changing water affinities on pipeline surfaces.

关键词： Deposition Natural gas hydrate Pipelines Water affinity Adhesion strength

Explainable-AI-based two-stage solution for WSN object localization using zero-touch mobile transceivers

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Science China(Information Sciences) 2024年第7期67卷 27-45页

作者： Kai FANG Junxin CHEN han ZHU Thippa Reddy GADEKALLU Xiaoping WU wei WANG School of Mathematics and Computer Science Zhejiang A&F University School of Software Dalian University of Technology Faculty of Applied Sciences Macao Polytechnic University Department of Electrical and Computer Engineering Lebanese American University School of Information Engineering Huzhou University Guangdong-Hong Kong-Macao Joint Laboratory for Emotional Intelligence and Pervasive Computing Artificial Intelligence Research Institute Shenzhen MSU-BIT University

Artificial intelligence technology is widely used in the field of wireless sensor networks(WSN).Due to its inexplicability, the interference factors in the process of WSN object localization cannot be effectively eliminated. In this paper, an explainable-AI-based two-stage solution is proposed for WSN object localization. In this solution, mobile transceivers are used to enlarge the positioning range and eliminate the blind area for object localization. The motion parameters of transceivers are considered to be unavailable,and the localization problem is highly nonlinear with respect to the unknown parameters. To address this,an explainable AI model is proposed to solve the localization problem. Since the relationship among the variables is difficult to fully include in the first-stage traditional model, we develop a two-stage explainable AI solution for this localization problem. The two-stage solution is actually a comprehensive consideration of the relationship between variables. The solution can continue to use the constraints unused in the firststage during the second-stage, thereby improving the performance of the solution. Therefore, the two-stage solution has stronger robustness compared to the closed-form solution. Experimental results show that the performance of both the two-stage solution and the traditional solution will be affected by numerical changes in unknown parameters. However, the two-stage solution performs better than the traditional solution, especially with a small number of mobile transceivers and sensors or in the presence of high noise. Furthermore,we have also verified the feasibility of the proposed explainable-AI-based two-stage solution.

关键词： explainable AI object localization semidefinite relaxation mobile transceiver two-stage solution closed-form solution

Interaction between catechol-O-methyltransferase Val/Met polymorphism and cognitive reserve for negative symptoms in schizophrenia

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World Journal of Psychiatry 2024年第5期14卷 695-703页

作者： Wen-Peng Hou Xiang-Qin Qin wei-wei Hou Yun-yi han Qi-Jing Bo Fang Dong Fu-Chun Zhou Xian-Bin Li Chuan-Yue Wang Beijing Key Laboratory of Mental Disorders National Clinical Research Center for Mental Disorders&National Center for Mental DisordersBeijing Anding HospitalCapital Medical UniversityBeijing 100088China Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijing 100069China

BACKGROUND Cognitive reserve(CR)and the catechol-O-methyltransferase(COMT)Val/Met polymorphism are reportedly linked to negative symptoms in ***,the regulatory effect of the COMT genotype on the relationship between CR and negative symptoms is still *** To investigate whether the relationship between CR and negative symptoms could be regulated by the COMT Val/Met *** In a cross-sectional study,54 clinically stable patients with schizophrenia underwent assessments for the COMT genotype,CR,and negative *** was estimated using scores in the information and similarities subtests of a short form of the Chinese version of the Wechsler Adult Intelligence *** COMT Met-carriers exhibited fewer negative symptoms than Val *** the total sample,significant negative correlations were found between negative symptoms and information,*** between information,similarities and negative symptoms were observed in Val homozygotes only,with information and similarities showing interaction effects with the COMT genotype in relation to negative symptoms(information,β=-0.282,95%CI:-0.552 to-0.011,P=0.042;similarities,β=-0.250,95%CI:-0.495 to-0.004,P=0.046).CONCLUSION This study provides initial evidence that the association between negative symptoms and CR is under the regulation of the COMT genotype in schizophrenia.

关键词： Catechol-O-methyltransferase Val/Met polymorphism Cognitive reserve Crystallized intelligence Negative symptoms Schizophrenia

Furfural residues derived nitrogen-sulfur co-doped sheet-like carbon: An excellent electrode for dual carbon lithium-ion capacitors

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Green Energy & Environment 2024年第9期9卷 1427-1439页

作者： Xiaoying Guo Yan Qiao Zonglin yi Christian Marcus Pedersen yingxiong Wang Xiaodong Tian Peide han College of Materials Science and Engineering Taiyuan University of Technology State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Key Laboratory of Carbon Materials Institute of Coal Chemistry Chinese Academy of Sciences Department of Chemistry University of Copenhagen Universitetsparken 5 College of Chemistry Taiyuan University of Technology

The state-of-the-art lithium-ion capacitors （LICs）,consisting of high-capacity battery-type anode and high-rate capacitor-type cathode,can deliver high energy density and large power density when comparing with traditional supercapacitors and lithium-ion batteries,***,the ion kinetics mismatch between cathode and anode leads to unsatisfied cycling lifetime and anode *** efforts have been devoted to solving the abovementioned *** promising strategy is altering high conductive hard carbon anode with excellent structural stability to match with activated carbon cathode,assembling dual-carbon *** this contribution,one-pot in-situ expansion and heteroatom doping strategy was adopted to prepare sheet-like hard carbon,while activated carbon was obtained involving *** persulfate was used as expanding and doping agent *** furfural residues （FR） were served as carbon *** resulting hard carbon （FRNS-HC） and activated carbon （FRNS-AC）show excellent electrochemical performance as negative and positive electrodes in a lithium-ion battery （LIB）.To be specific,374.2 m Ah g-1and 123.1 m Ah g-1can be achieved at 0.1 A g-1and 5 A g-1when FRNS-HC was tested as *** combined with a highly porous carbon cathode (SBET=2961 m2g-1) synthesized from the same precursor,the LIC showed high specific energy of147.67 Wh kg-1at approximately 199.93 W kg-1,and outstanding cycling life with negligible capacitance fading over 1000 *** study could lead the way for the development of heteroatom-doped porous carbon nanomaterials applied to Li-based energy storage applications.

关键词： Furfural residue Ammonium persulfate Sheet-like carbon Lithium-ion capacitors Hard carbon

Security Constrained Distributed Transaction Model for Multiple Prosumers

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 834-843页

作者： Haiteng han Sichen Shen Zhinong wei Mohammed Olama Haixiang Zang Guoqiang Sun yizhou Zhou School of Electrical and Power Engineering Hohai UniversityNanjing 211100China Oak Ridge National Laboratory Oak RidgeTN 37831 USA

Massive access of renewable energy has prompted demand-side distributed resources to participate in regulation and improve flexibility of power systems. With large-scale access of massive, decentralized, and diverse distributed resources, demand-side market members have transformed from traditional “consumers” to “prosumers”. To explore the distributed transaction model of prosumers, in this paper, a multi-prosumer distributed transaction model is proposed, and the Conditional Value-at-Risk (CVaR) theory is applied to quantify potential risks caused by the stochastic characteristics inherited from renewable energy. First, a prosumer model under constraints of the distribution network including photovoltaic units, fuel cells, energy storage system, central air conditioning and flexible loads is established, and a multi-prosumer distributed transaction strategy is proposed to achieve power sharing among multiple prosumers. Second, a prosumer transaction model based on CVaR is constructed to measure risks inherited from the uncertainty of PV output within the prosumer and ensure safety of system operation in extreme PV output scenarios. Then, the alternating direction multiplier method (ADMM) is utilized to solve the constructed model efficiently. Finally, distributed transaction costs of prosumers are distributed fairly based on the generalized Nash equilibrium to maximize social benefits. Simulation results show the multi-prosumer distributed transaction mechanism established under the proposed generalized Nash equilibrium method can encourage power sharing among prosumers, increasing their own income and social benefits. Also, the CVaR can assist decision making of prosumers in weighting the risks and benefits, improving system resilience through energy management of prosumers.

关键词： Alternating direction multiplier method Conditional Value-at-Risk distributed transaction generalized Nash equilibrium prosumer