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Towards efficient generative AI and beyond-AI computing:New trends on ISSCC 2.2. machine learning accelerators

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Journal of Semiconductors 2024年第4期45卷 12-15页

作者： bohan Yang Jia Chen Fengbin Tu Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyHong KongChina AI Chip Center for Emerging Smart Systems The Hong Kong University of Science and TechnologyHong KongChina School of the Gifted Young University of Science and Technology of ChinaHefei 230026Chin

Compared to the last decade when the convolution neu-ral network(CNN)dominated the research field,machine learn-ing(ML)algorithms have reached a pivotal moment called the generative artificial intelligence(AI)*** the emer-gence of large-scale foundation models[1],such as large multi-modal model(LMM)GPT-4[2.and text-to-image generative model DALL·E[3].

关键词： ISSCC beyond AI

Parametric formation control of multiple nanosatellites for cooperative observation of China Space Station

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Astrodynamics 2024年第1期8卷 77-95页

作者： Hao Zhou bohan Jiao Zhaohui Dang Jianping Yuan School of Astronautics Northwestern Polytechnical UniversityXi’an710072China National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an710072China

This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple ***,a simplified geometrical model of the CSS is constructed using fundamental solids,such as the capsule body and ***,the spacecraft formation configuration for the observation mission is characterized by a three-dimensional(3D)Lissajous curve using related design parameters under the full-coverage observation requirements of specific parts,such as the CSS connecting section and collision avoidance ***,a double-layer control law is designed for each nanosatellite,in which the upper layer is a distributed observer for recognizing the target formation configuration parameters,and the lower layer is a trajectory-tracking controller to make the nanosatellite converge to its temporary target position calculated from the upper layer’s *** closed-loop control stability is proven under the condition that the communication network topology of the nanosatellite cluster contains a directed spanning ***,the control method is verified by numerical simulation,where the CSS connecting section is selected as the observation target,and ten small nanosatellites are assumed to perform the cooperative observation *** simulation results demonstrate that the double-layer control law is robust to single-point communication failures and suitable for the accompanying missions of large space objects with multiple nanosatellites.

关键词： China Space Station(CSS) cooperative observation parametric formation 3D Lissajous curve double-layer system

Interregional compensation for farmland protection:From the perspective of farmland allocation optimization

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Journal of Geographical Sciences 2024年第7期34卷 1437-1454页

作者： YANG bohan SHENG Siyu SHANGGUAN Ziheng KE Xinli School of Public Administration Central China Normal UniversityWuhan430079China School of Business Hubei UniversityWuhan430000China College of Public Administration Huazhong Agricultural UniversityWuhan430070China

Interregional compensation for farmland protection(IRCFP)is a policy instrument for encouraging farmland protection through interregional fiscal transfer *** practices and studies on IRCFP have generally determined the payers and recipients of compensation based on the present distribution of farmland,and the compensation standards did not combine farmland development right value with farmland deficit and surplus,resulting in insignificant effects on farmland protection and even policy ***,in this study,we proposed an interregional compensation mechanism for farmland protection based on farmland allocation optimization by considering 31 provincial-level regions in *** results showed that(1)the determination of farmland surplus or deficit areas based on farmland allocation optimization met the regional construction land demand from the perspective of achieving food security.(2.The combination of the compensation value standard and cropland deficit and surplus had a positive effect on farmland protection.(3)Interregional compensation for farmland protection based on farmland allocation optimization can coordinate economic development,farmland protection,and ecological ***,we discussed the rationality of interregional compensation for farmland protection based on farmland allocation optimization and designed the operation mechanism of IRCFP.

关键词： interregional compensation farmland allocation optimization farmland protection land development rights China

Effects of soil crust on the collapsing erosion of colluvial deposits with granite residual soil

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Journal of Mountain Science 2024年第8期21卷 2579-2591页

作者： LIU Weiping ZENG bohan WANG Tianhuan DUAN Junyi School of Infrastructure Engineering Nanchang UniversityNanchang 330031China

Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion ***,the impacts of soil crust conditions on the erosion of colluvial deposits with granite residual soils have only been studied to a limited *** address this issue,this study investigates the impacts of three soil crust conditions(i.e.,without crust,10-minute crust,and 2.-minute crust)on gully morphology,rainfall infiltration,and runoff and sediment yield during slope erosion of colluvial deposits with granite residues(classified as Acrisols)in Yudu County,Ganzhou City,Jiangxi Province,China,using simulated rainfall tests and photographic *** results showed that as the strength of the soil crust increased,the capacity of moisture infiltration and the width and depth of the gully as well as the sediment concentration and yield ratio decreased;at the same time,the runoff ratio *** sediment yield in the without-crust test was found to be 1.2. and 1.43 times higher than that observed in the 10-minute crust and 2.-minute crust tests,*** results indicate that soil crusts can effectively prevent slope erosion and moisture infiltration,while providing valuable insights for the management of soil erosion in natural environments.

关键词： Granite residual soil Colluvial deposits Slope erosion Soil crust Sediment yield

Structural engineering of BaWO_(4)/CsPbX_(3)/CsPb_(2.X_(5)(X=Cl,Br,I)heterostructures towards ultrastable and tunable photoluminescence

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Nano Research 2024年第3期17卷 1636-1645页

作者： Peng Liu Yan Xu bohan Li Yuchi Zhang Hongzhou Lian Jun Lin Department of Chemistry College of SciencesNortheastern UniversityShenyang 110819China State Key Laboratory of Rare Earth Resource Utilization Chang Chun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Construction of lead halide perovskite nanocrystals(LHP NCs)heterostructures is essential to obtain highly stable photoluminescence and expand their ***,a novel self-assembly strategy combining with a solvent-free thermal-assisted synthesis and a water-triggered reaction is developed to subsequently grow BaWO_(4)/CsPbX_(3)/CsPb_(2.X_(5)(X=Cl,Br,I)heterostructures at low nucleation temperature with high *** as-obtained ternary BaWO_(4)/CsPbX_(3)/CsPb_(2.X_(5)(X=Cl,Br,I)heterostructures exhibit remarkably enhanced panchromatic emission and ultrastable luminescence ascribing to the low-defect growth based on lattice *** white light-emitting diodes(WLEDs)have been constructed with a high correlated color temperature(CCT)of 72.5 K and luminous efficiency of 74.4 lm·***^(3+)-doped BaWO_(4)/CsPbX_(3)/CsPb_(2.X_(5)(Ln^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Sm^(3+),Yb^(3+)/Er^(3+))nanocomposites are further designed with excitation-dependent photoluminescence and thermochromic properties,making them excellent candidates for high-level anti-counterfeiting and *** work offers a green and universal approach in assembling CsPbX_(3)(X=Cl,Br,I)on lattice-matched tungstate with adjustable panchromatic emission for versatile optical applications.

关键词： inorganic lead halide perovskites solvent-free synthesis panchromatic emission anti-counterfeiting and encryption application

Regulation of the multi-emission centers in carbon dots via a bottom-up synthesis approach

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Chinese Chemical Letters 2024年第9期35卷 238-242页

作者： bohan Zhang Bingzhe Wang Guichuan Xing Zikang Tang Songnan Qu Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacao 999078China

Understanding the luminescence mechanisms and regulating the emission centers of carbon dots(CDs)are important for advancing their related *** this work,we systematically investigate the formation processes of multi-emission centers in CDs synthesized through a bottom-up approach by controlling the solvothermal reaction *** synthesized at a lower temperature(140℃,140-CDs)exhibit smaller particle sizes(3–4 nm)with dominant green–yellow emission,while CDs synthesized at a higher temperature(180℃,180-CDs)exhibit larger particle sizes(8–9 nm)with enhanced red emission and emerging near-infrared(NIR)*** green–yellow emission and red emission originate from the core state and the surface-related state,respectively,and the emissions could be regulated by temperature-controlled dehydration and carbonization *** clear NIR emission center in 180-CDs is attributable to the increased content of radical defects in the cores during the increased dehydration and carbonization processes during higher-temperature solvothermal treatment.

关键词： Carbon dot Photoluminescence Defect state Core state Temperature regulation

Regulation of rhizosphere microenvironment by rice husk ash for reducing the accumulation of cadmium and arsenic in rice

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Journal of Environmental Sciences 2024年第2期136卷 1-10页

作者： Yi Jiang Ya Liu Xuantao Yi Peng Zeng bohan Liao Hang Zhou Jiaofeng Gu College of Environmental Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China Hunan Engineering Laboratory for Control of Rice Quality and Safety Changsha 410004China

It is important to reduce Cd and As content in brown rice in contaminated paddy *** conducted research on the effects of rice husk ash (RHA) on the Cd and As in the rhizosphere microenvironment (soil,porewater,and iron plaque) and measured the Cd,As,and Si content in rice *** main elements in RHA were Si (2..64%) and O (69.17%),which had the maximum adsorption capacity for Cd was 42.49 mg/kg and for As was 18.62.mg/*** pH and available Si content increased,while soil available Cd and As decreased following application of 0.5%–2.*** promote the transformation of Cd to insoluble fraction,while As was transformed from a poorly soluble form to a more active *** reduced Cd content and increased Si content in porewater,and reduced As only at the later rice growth *** increased the amount of iron plaque,thereby decreasing the Cd content in iron plaque,while increased the As content in *** and inorganic As content in brown rice were decreased,to 0.31 mg/kg and 0.18 mg/kg,*** decrease of Cd in brown rice was due to the decrease of Cd mobility in soil,thereby reducing root accumulation,while the decrease of As in brown rice was affected by the transport from roots to ***,RHA can be considered as a safe and efficient in-situ remediation amendment for Cd and As co-contaminated paddy soil.

关键词： Rice husk ash(rha) Cadmium Arsenic Silicon Rice Soil

Experimental study on the compression-shear performance of a new-type circumferential joint of shield tunnel

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Underground Space 2024年第1期14卷 138-155页

作者： Ziyang Zhou Kun Feng Yiteng Liu bohan Wu Chunfang Lu Gang Lin Chuan He Key Laboratory of Transportation Tunnel Engineering of Ministry of Education Southwest Jiaotong UniversityChengdu 610031China China Academy of Railway Sciences Corporation Limited Beijing 100081China China Railway Eryuan Engineering Group Co. Ltd.Chengdu 610031China

To investigate the compression-shear behavior of a new circumferential joint based on the sleeve-straight bolt combination type connection of large-diameter shield tunnels,a series of full-scale joint experiments was carried *** the process of the experiment,more attention was paid to the specimen displacement,bolt stress and joint damage *** the basis of these experiment phenomena,this study discussed the compression-shear bearing process of the new connector,analyzed the damage mode of the joint structure,and finally evaluated the performance of the new *** is found that the bearing process of the joint can be divided into four stages:the transitional stage for overcoming the friction of the concrete,the sleeve bearing stage for the sleeve bearing shear loads alone,the combined bearing stage for bearing shear loads by the connector system,and the structural damage stage for structural instability and *** speaking,affected by connector position and hand hole,the positive compression-shear stiffness of the joint is less than the negative compression-shear stiffness,and the positive shear strength of the joint is greater than the negative shear *** increase of longitudinal axial force will improve the compression-shear performance of the *** relationship between longitudinal axial force and joint stiffness is a logarithmic *** use of new type of connector can effectively improve the compression-shear stiffness of joints under low shear loads,but the application of straight bolts will lose part of the strength performance.

关键词： Shield tunnel New type of connector Shear resistance Full-scale experiment Circumferential joint

An effective strategy to inhibit grain coarsening:Construction of multi-element co-segregated grain boundary complexion

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Journal of Advanced Ceramics 2024年第7期13卷 1060-1071页

作者： Le Fu Gabriel Arcuri Wenjun Yu bohan Wang Zihua Lei Ying Deng Kathryn Grandfield School of Material Science and Engineering Central South UniversityChangsha 410083China Canadian Centre for Electron Microscopy McMaster UniversityHamilton L8S 4L8Canada State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Materials Science and Engineering McMaster UniversityHamilton L8S 4L8Canada

When exposed to moderate to high temperatures,nanomaterials typically suffer from severe grain coarsening,which has long been a major concern that prevents their wider ***,we proposed an effective strategy to inhibit grain coarsening by constructing grain boundary(GB)complexions with multiple codoped dopants,which hindered coarsening from both energetic and kinetic *** demonstrate the feasibility of this strategy,multiple selected dopants were doped into a ZrO_(2.-SiO_(2.nanocrystalline glass ceramic(NCGC)to form GB *** results showed that NCGC was predominantly composed of ZrO_(2.nanocrystallites(NCs)distributed in an amorphous SiO_(2.*** layers of GB complexions(~2.5 nm)were formed between adjacent ZrO_(2.NCs,and they were crystalline superstructures with co-segregated *** addition,a small amount of quartz solid solution was formed,and it adhered to the periphery of ZrO_(2.NCs and bridged the adjacent NCs,acting as a“bridging phase”.The GB complexions and the“bridging phase”synergistically enhanced the coarsening resistance of ZrO_(2.NCs up to 1000°*** findings are important for understanding GB complexions and are expected to provide new insights into the design of nanomaterials with excellent thermodynamic stability.

关键词： Zr_(2.-Si_(2. multi-element co-segregation grain boundary(GB)complexion grain coarsening atom probe tomography(APT)