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Reinforcement learning based edge computing in B5G

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Digital Communications and Networks 2024年第1期10卷 1-6页

作者： Jiachen Yang Yiwen Sun Yutian Lei Zhuo Zhang Yang li Yongjun Bao Zhihan Lv School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Technology and Data Center ***Beijing100176China School of Data Science and Software Engineering Qingdao UniversityQingdao266101China

The development of communication technology will promote the application of Internet of Things,and Beyond 5G will become a new technology *** the same time,Beyond 5G will become one of the important supports for the development of edge computing *** paper proposes a communication task allocation algorithm based on deep reinforcement learning for vehicle-to-pedestrian communication scenarios in edge *** trial and error learning of agent,the optimal spectrum and power can be determined for transmission without global information,so as to balance the communication between vehicle-to-pedestrian and *** results show that the agent can effectively improve vehicle-to-infrastructure communication rate as well as meeting the delay constraints on the vehicle-to-pedestrian link.

关键词： Reinforcement learning Edge computing Beyond 5G Vehicle-to-pedestrian

Hydrogen evolution reaction activity enhancement from active site turnover mechanism

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Journal of Energy Chemistry 2024年第5期92卷 629-638页

作者： Jiacheng Wang Tongqing Yang Xiyue li Haiqin Zhang Yixue Zhang Yan He Hongyao Xue College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061ShandongChina

Although heteroatom doping is an effective way to improve the catalytic activity of transition metal phosphides(TMPs),the mechanism of activity enhancement needs to be further *** this end,we synthesized a Co-doped Ni_(2)P catalyst as a research model and found that the introduction of heterogeneous Co reconstructed the charge distribution around the P site,which effectively enhanced the hydrogen evolution reaction(HER)activity of the pure Ni_(2)*** on in-situ Raman real-time monitoring technology,we monitored for the first time that Co doping triggered a switch of the active site(from the original Co-active site to the P-active site),which promoted the adsorption of H_(2)O to enhance the HER *** density functional theory(DFT)calculations indicated that the P site of Co-Ni_(2)P expressed the highest activity and the Ni site of pure Ni_(2)P expressed the highest activity,which further confirms the in-situ Raman monitoring *** active site turnover mechanism discovered in this study will undoubtedly provide more rational and targeted ideas for future catalyst design.

关键词： In-situ Raman observation Heteroatom doping Activesites turnover Hydrogen production

Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

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Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng li Ming-Wei Zhang Ji-Wu Xin Lei Wei Wen-Yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

过氧化氢定期消毒结合持续消毒对口腔综合治疗台水路污染控制的有效性观察

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四川大学学报（医学版） 2024年第1期55卷 217-223页

作者：常婧党芸王春丽李秀娥北京大学口腔医学院·口腔医院第五门诊部国家口腔医学中心国家口腔疾病临床医学研究中心口腔生物材料和数字诊疗装备国家工程研究中心北京100081 北京大学口腔医学院·口腔医院护理部国家口腔医学中心国家口腔疾病临床医学研究中心口腔生物材料和数字诊疗装备国家工程研究中心北京100081

目的观察过氧化氢定期消毒结合持续消毒对国内口腔综合治疗台水路污染控制的有效性,为选择水路消毒措施提供参考依据。方法采用便利抽样法选择某口腔专科医院4台口腔综合治疗台。采用每4周1次的定期消毒结合持续消毒的方式对口腔综合治... 详细信息

目的观察过氧化氢定期消毒结合持续消毒对国内口腔综合治疗台水路污染控制的有效性,为选择水路消毒措施提供参考依据。方法采用便利抽样法选择某口腔专科医院4台口腔综合治疗台。采用每4周1次的定期消毒结合持续消毒的方式对口腔综合治疗台水路进行消毒(口腔综合治疗台停用超3 d则额外增加1次定期消毒)。定期消毒指利用口腔综合治疗台自带的水路消毒装置使过氧化氢复合消毒剂原液(质量体积比为1.4%的过氧化氢)在水路中充盈,浸泡消毒24 h后排空。持续消毒指以质量体积比0.014%过氧化氢溶液作为诊疗用水,并在开诊前用其冲洗水路2 min,每次诊疗结束后用其冲洗水路30 s。研究持续25周,定期消毒7次,其余诊疗时间进行持续消毒。第1次消毒当日未使用消毒液时(基线)和消毒期间采集高速牙科手机和三用枪出水口水样,细菌培养后计算菌落总数和合格率,水样菌落总数≤100 CFU/mL即为合格水样;第1次消毒当日未使用消毒液时(基线)、消毒25周后分别采集1台口腔综合治疗台的高速牙科手机供水管路各1 cm,扫描电镜下观察生物膜形态。结果共采集水样352份,基线水样8份,菌落总数中位数为3140 CFU/mL,消毒后第1日诊疗用水菌落总数中位数为7.5 CFU/mL,消毒前后诊疗用水菌落总数差异有统计学意义(P=0.012);消毒后水样344份,三用枪和高速牙科手机水样菌落总数中位数为11 CFU/mL和11 CFU/mL,菌落总数差异无统计学意义;合格率分别为83.7%(144/172)和82.0%(141/172),合格率差异无统计学意义;消毒第1至9周期间,除第3周外,其余8周诊疗用水合格率均大于80%。在第14周至17周、第18至21周的2个定期消毒周期内,仅前2周合格率保持在80%以上,从第3周开始下降。扫描电镜下观察生物膜形态,基线的生物膜结构致密,有大量细菌混合;消毒25周后,生物膜结构疏松,未见大量细菌留存的连贯性特征。结论过氧化氢定期消毒结合持续消毒的方式,可有效控制口腔综合治疗台水路污染,但需结合实际情况,进一步探讨定期消毒周期及持续消毒时过氧化氢浓度。

关键词：口腔综合治疗台水路过氧化氢消毒

Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 157-169页

作者： Rui Wang Zhiming Zhou Kaiwen li Tao Zhang ling Wang Xin Xu Xiangke liao IEEE the Xiangjiang Laboratory and the College of Systems Engineering National University of Defense TechnologyChangsha 410073China the Institute of Automation Chinese Academy of SciencesBeijing 100190China the College of Systems Engineering National University of Defense TechnologyChangsha 410073 the Hunan Key Laboratory of Multi-Energy System Intelligent Interconnection Technology Changsha 410073China the Department of Automation Tsinghua UniversityBeijing 100084China the College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China the College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Traditional expert-designed branching rules in branch-and-bound(B&B) are static, often failing to adapt to diverse and evolving problem instances. Crafting these rules is labor-intensive, and may not scale well with complex *** the frequent need to solve varied combinatorial optimization problems, leveraging statistical learning to auto-tune B&B algorithms for specific problem classes becomes attractive. This paper proposes a graph pointer network model to learn the branch rules. Graph features, global features and historical features are designated to represent the solver state. The graph neural network processes graph features, while the pointer mechanism assimilates the global and historical features to finally determine the variable on which to branch. The model is trained to imitate the expert strong branching rule by a tailored top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. It also outperforms state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.

关键词： Branch-and-bound(B&B) combinatorial optimization deep learning graph neural network imitation learning

An adaptive finite-difference method for seismic traveltime modeling based on 3D eikonal equation

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Petroleum Science 2024年第1期21卷 195-205页

作者： Bao-Ping Qiao Qing-Qing li Wei-Guang He Dan Zhao Qu-Bo Wu CNNC Beijing Research Institute of Uranium Geology Beijing 100029China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShangdongChina SINOPEC Geophysical Research Institute Nanjing211103JiangsuChina

3D eikonal equation is a partial differential equation for the calculation of first-arrival traveltimes and has been widely applied in many scopes such as ray tracing,source localization,reflection migration,seismic monitoring and tomographic *** recent years,many advanced methods have been developed to solve the 3D eikonal equation in heterogeneous ***,there are still challenges for the stable and accurate calculation of first-arrival traveltimes in 3D strongly inhomogeneous *** this paper,we propose an adaptive finite-difference(AFD)method to numerically solve the 3D eikonal *** novel method makes full use of the advantages of different local operators characterizing different seismic wave types to calculate factors and traveltimes,and then the most accurate factor and traveltime are adaptively selected for the convergent updating based on the Fermat *** with global fast sweeping describing seismic waves propagating along eight directions in 3D media,our novel method can achieve the robust calculation of first-arrival traveltimes with high precision at grid points either near source point or far away from source point even in a velocity model with large and sharp *** numerical examples show the good performance of the AFD method,which will be beneficial to many scientific applications.

关键词： 3D eikonal equation Accurate traveltimes Global fast sweeping 3D inhomogeneous media Adaptive finite-difference method

New perspectives on the therapeutic potential of quercetin in non-communicable diseases:Targeting Nrf2 to counteract oxidative stress and inflammation

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Journal of Pharmaceutical Analysis 2024年第6期14卷 805-822页

作者： li Zhang li-Yue Xu Fei Tang Dong liu Xiao-Lan Zhao Jing-Nan Zhang Jia Xia Jiao-Jiao Wu Yu Yang Cheng Peng Hui Ao State Key Laboratory of Southwestern Chinese Medicine Resources School of PharmacyChengdu University of Traditional Chinese MedicineChengdu611137China Innovative Institute of Chinese Medicine and Pharmacy Chengdu University of Traditional Chinese MedicineChengdu611137China

Non-communicable diseases(NCDs),including cardiovascular diseases,cancer,metabolic diseases,and skeletal diseases,pose significant challenges to public health *** complex pathogenesis of these diseases is closely linked to oxidative stress and inflammatory *** factor erythroid 2-related factor 2(Nrf2),a critical transcription factor,plays an important role in regulating antioxidant and anti-inflammatory responses to protect the cells from oxidative damage and inflammation-mediated ***,Nrf2-targeting therapies hold promise for preventing and treating ***(Que)is a widely available flavonoid that has significant antioxidant and anti-inflammatory *** modulates the Nrf2 signaling pathway to ameliorate oxidative stress and *** modulates mitochondrial function,apoptosis,autophagy,and cell damage biomarkers to regulate oxidative stress and inflammation,highlighting its efficacy as a therapeutic agent against ***,we discussed,for the first time,the close association between NCD pathogenesis and the Nrf2 signaling pathway,involved in neurodegenerative diseases(NDDs),cardiovascular disease,cancers,organ damage,and bone ***,we reviewed the availability,pharmacokinetics,pharmaceutics,and therapeutic applications of Que in treating *** addition,we focused on the challenges and prospects for its clinical *** represents a promising candidate for the treatment of NCDs due to its Nrf2-targeting properties.

关键词： Quercetin Nrf2 Non-communicable diseases Antioxidant Anti-inflammatory Availability

Strong synergy between physical and chemical properties:Insight into optimization of atomically dispersed oxygen reduction catalysts

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Journal of Energy Chemistry 2024年第4期91卷 36-49页

作者： Yifan Zhang linsheng liu Yuxuan li Xueqin Mu Shichun Mu Suli liu Zhihui Dai School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816JiangsuChina State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology InstitutionWuhan 430070HubeiChina School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023JiangsuChina

Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utilization and exceptional catalytic ***,accurately controlling atomic physical properties including spin,charge,orbital,and lattice degrees of atomically dispersed catalysts can realize the optimized chemical properties including maximum atom utilization efficiency,homogenous active centers,and satisfactory catalytic performance,but remains ***,through physical and chemical insight,we review and systematically summarize the strategies to optimize atomically dispersed ORR catalysts including adjusting the atomic coordination environment,adjacent electronic orbital and site density,and the choice of dual-atom *** the emphasis is on the fundamental understanding of the correlation between the physical property and the catalytic behavior for atomically dispersed ***,an overview of the existing challenges and prospects to illustrate the current obstacles and potential opportunities for the advancement of atomically dispersed catalysts in the realm of electrocatalytic reactions is offered.

关键词： Atomically dispersed catalysts Coordination environment Electronic orbitals Inter-site distance effect Oxygen reduction reaction

Particle size dependence of the microsegregation and microstructure in the atomized Ni-based superalloy powders:Theoretical and experimental study

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Journal of Materials Science & Technology 2024年第4期171卷 54-65页

作者： Jikang li Mingsheng Yang yunfei Cai Yuanyuan Zhang Qingshuai Feng Jiantao liu Tong liu Key Laboratory of Aerospace Materials and Performance(Ministry of Education)School of Materials Science and Engineering Beihang UniversityBeijing 100191China Central Iron and Steel Research Institute Beijing 100081China

The microstructure and microsegregation of atomized powder,which depend on their sizes,are of great importance to the mechanical properties of the consolidated bulk ***,it is necessary to reveal the relationship between particle size and powder *** effects of particle size on the so-lidification characterization of the atomized Ni-based superalloy powders were studied via finite element *** on the simulations,a model was developed to predict the microsegregation and mi-crostructure of atomized powders with different sizes and study the influence of thermal history on the powder attributes during the atomization *** radiation heat transfer and temperature gradi-ent within the rapid solidification alloy powders were taken into account in this *** validating the accuracy of the model,the predictions of the present model were compared with the microsegregation and microstructure of the specific size powder close to the screen mesh *** results showed that mi-crostructure depended primarily on the temperature gradient within the powder,while the solidification rate had a more significant effect on the *** model predicted microstructure features in agreement with the experiment,and for microsegregation,the deviations of prediction for most ele-ments were less than 10%.This work provides a new model to precisely predict the microsegregation and microstructure of the atomized alloy powders and sets a foundation to control the powder features for various engineering applications.

关键词： Particle size Solidification microstructure Microsegregation Numerical simulation