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Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

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

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Weavable thermoelectrics: advances, controversies, and future developments

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Materials Futures 2024年第1期3卷 63-94页

作者： Xiao-Lei Shi Shuai Sun Ting Wu Jian Tu zhiming zhou Qingfeng Liu Zhi-Gang Chen School of Chemistry and Physics ARC Research Hub in Zero-emission Power Generation for Carbon Neutralityand Centre for Materials ScienceQueensland University of TechnologyBrisbaneQueensland4000Australia State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211800People’s Republic of China School of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054People’s Republic of China

Owing to the capability of the conversion between thermal energy and electrical energy and their advantages of light weight,compactness,noise-free operation,and precision reliability,wearable thermoelectrics show great potential for diverse *** them,weavable thermoelectrics,a subclass with inherent flexibility,wearability,and operability,find utility in harnessing waste heat from irregular heat *** the rapid advancements in this field,a timely review is essential to consolidate the progress and ***,we provide an overview of the state of weavable thermoelectric materials and devices in wearable smart textiles,encompassing mechanisms,materials,fabrications,device structures,and applications from recent advancements,challenges,and *** review can serve as a valuable reference for researchers in the field of flexible wearable thermoelectric materials and devices and their applications.

关键词： thermoelectric weaving materials structure device

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心脏移植中应用边缘供心的预后分析

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中华胸心血管外科杂志 2024年第1期40卷 50-54页

作者：耿俊义周强周志明常峰荣郭长英郑州市第七人民医院外科重症监护室郑州450016 郑州市第七人民医院外科心脏移植中心郑州450016

目的探讨心脏移植中应用边缘供心患者的预后。方法回顾性纳入郑州市第七人民医院2018年4月至2022年11月期间的连续心脏移植受者和供者的临床资料。根据边缘供心的定义,将受体患者分为常规供心组(117例)和边缘供心组(62例),分析两组患者... 详细信息

目的探讨心脏移植中应用边缘供心患者的预后。方法回顾性纳入郑州市第七人民医院2018年4月至2022年11月期间的连续心脏移植受者和供者的临床资料。根据边缘供心的定义,将受体患者分为常规供心组(117例)和边缘供心组(62例),分析两组患者的心脏移植术前、术后资料。结果边缘供心形成的主要原因是供心冷缺血时间>6 h;术前使用体外膜肺氧合和机械通气更容易接收到边缘供心;心脏移植中利用边缘供心,术后机械通气时间和监护室停留时间增加;使用边缘供心患者的生存率比常规供心患者低,但差异无统计学意义。结论心脏移植中应用边缘供心是解决心脏器官短缺,减少移植等待者死亡的有效方法。

关键词：心脏移植边缘供心预后分析

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高效液相色谱法测定染发产品中48种准用染料

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分析试验室 2024年第7期43卷 966-973页

作者：李静陈张好周智明国家药品监督管理局化妆品风险评估重点实验室广东省药品检验所广州510525

采用多色谱系统建立了化妆品中48种准用染料的高效液相色谱检测方法。样品以甲醇-2 g/L亚硫酸氢钠溶液(1∶1,V/V)溶解,冰浴超声提取,10000 r/min离心5 min后测定。采用SHIMADZU Shimpack GIST C18色谱柱(250 mm×4.6 mm,5μm),甲醇、乙... 详细信息

采用多色谱系统建立了化妆品中48种准用染料的高效液相色谱检测方法。样品以甲醇-2 g/L亚硫酸氢钠溶液(1∶1,V/V)溶解,冰浴超声提取,10000 r/min离心5 min后测定。采用SHIMADZU Shimpack GIST C18色谱柱(250 mm×4.6 mm,5μm),甲醇、乙腈和20 mmol/L磷酸氢二钠溶液(pH 7.5)为流动相,将48种染料分3个液相系统梯度洗脱。结果表明,48种染料在考察的质量浓度范围内线性关系良好,相关系数均大于0.99,方法的检出限为4~100μg/g,加标回收率为80.1%~118.6%,相对标准偏差为0.3%~9.8%。本方法的检测范围覆盖了化妆品中常用的48种准用染料,适用于染发产品中染料标识真实性及使用浓度合规性的监督检查。

关键词：准用染料高效液相色谱染发剂

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高效液相色谱-串联质谱法测定化妆品中12种N-亚硝胺类物质

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分析试验室 2024年第4期43卷 528-534页

作者：李静周智明陈张好陆土柳国家药品监督管理局化妆品风险评估重点实验室(广东省药品检验所) 广州510525

建立了化妆品中12种N-亚硝胺类物质的高效液相色谱-串联三重四极杆质谱(HPLC-MS/MS)检测方法。0.5 g样品用25 mL 50%(V/V)甲醇水溶液溶解后,冰浴超声提取5 min, 10000 r/min离心5 min净化,以PFP色谱柱为分析柱,5 mmol/L甲酸胺(含0.1%甲... 详细信息

建立了化妆品中12种N-亚硝胺类物质的高效液相色谱-串联三重四极杆质谱(HPLC-MS/MS)检测方法。0.5 g样品用25 mL 50%(V/V)甲醇水溶液溶解后,冰浴超声提取5 min, 10000 r/min离心5 min净化,以PFP色谱柱为分析柱,5 mmol/L甲酸胺(含0.1%甲酸)水溶液-甲醇为流动相梯度洗脱,大气压化学电离源电离后正离子、多反应监测模式测定,外标法定量。12种亚硝胺类物质在5~200μg/L范围内线性良好(r^(2)>0.99),检出限为5~50μg/kg。膏霜、乳液和水剂3种基质的平均回收率为78.9%~119.7%,相对标准偏差为0.71%~8.8%。本方法能够为化妆品中12种亚硝胺类物质的监测评估提供技术手段。

关键词： N-亚硝胺类物质高效液相色谱-串联质谱法化妆品

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基于改进近端策略优化的空战自主决策研究

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系统仿真学报 2024年第9期36卷 2208-2218页

作者：钱殿伟齐红敏刘振周志明易建强华北电力大学控制与计算机工程学院北京102206 中国科学院自动化研究所北京100190

针对传统强化学习在空战自主决策应用中信息冗余度高、收敛速度慢等问题,提出一种基于双重观测与复合奖励的近端策略优化空战自主决策算法。设计了以交互信息为主、个体特征信息为辅的双重观测信息,降低战场信息高度冗余对训练效率的影... 详细信息

针对传统强化学习在空战自主决策应用中信息冗余度高、收敛速度慢等问题,提出一种基于双重观测与复合奖励的近端策略优化空战自主决策算法。设计了以交互信息为主、个体特征信息为辅的双重观测信息,降低战场信息高度冗余对训练效率的影响;设计了结果奖励和过程奖励相结合的复合奖励函数,提高了训练过程收敛速度;采用广义优势函数估计,改进了近端策略优化算法,提高优势函数估计的准确性。仿真结果表明:在对战固定程控对手和矩阵博弈对手实验场景中,该算法决策模型均可根据战场态势准确进行自主决策,完成空战任务。

关键词：强化学习空战自主决策双重观测复合奖励广义优势函数估计

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Hydrogen production from steam reforming of methanol over CuO/ZnO/Al_2O_3 catalysts: Catalytic performance and kinetic modeling

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Chinese Journal of Chemical Engineering 2016年第9期24卷 1186-1194页

作者： Yu Wan zhiming zhou Zhenmin Cheng State Key Laboratory of Chemical Engineering East China University of Science and Technology

A series of CuO/ZnO/Al_2O_3, CuO/ZnO/ZrO_2/Al_2O_3 and CuO/ZnO/CeO_2/Al_2O_3 catalysts were prepared by coprecipitation and characterized by N_2 adsorption, XRD, TPR, N_2O titration and HRTEM. The catalytic performances of these catalysts for the steam reforming of methanol were evaluated in a laboratory-scale fixed-bed reactor at 0.1 MPa and temperatures between 473 and 543 K. The results showed that the catalytic activity depended greatly on the catalyst reducibility and the specific surface area of Cu. An approximate linear correlation between the catalytic activity and the Cu surface area was found for all catalysts investigated in this *** to CuO/ZnO/Al_2O_3, the ZrO_2-doped CuO/ZnO/Al_2O_3 exhibited higher activity and selectivity to CO,while the CeO_2-doped catalyst displayed lower activity and selectivity. Finally, an intrinsic kinetic study was carried out over a screened CuO/ZnO/CeO_2/Al_2O_3 catalyst in the absence of internal and external mass transfer effects. A good agreement was observed between the model-derived effluent concentrations of CO(CO_2) and the experimental data. The activation energies for the reactions of methanol-steam reforming, water-gas shift and methanol decomposition over CuO/ZnO/CeO_2/Al_2O_3 were 93.1, 85.1 and 116.5 k J·mol^(-1), respectively.

关键词： Steam reforming of methanol CuO/ZnO/Al2O3 Dopants Cu surface area Kinetics

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材料加工专业课程思政的建设与实践

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重庆电力高等专科学校学报 2024年第3期29卷 36-39页

作者：涂坚周志明重庆理工大学材料科学与工程学院重庆400054

在阐述思政元素融入专业课所存在的问题基础上,提出了课程思政融入专业课程的具体实施方案——从工匠精神出发,以任务驱动为核心,结合数字媒介、课程作业、实践平台等多途径教学手段,形成具有特色的材料加工专业课程思政教学。本文具有... 详细信息

在阐述思政元素融入专业课所存在的问题基础上,提出了课程思政融入专业课程的具体实施方案——从工匠精神出发,以任务驱动为核心,结合数字媒介、课程作业、实践平台等多途径教学手段,形成具有特色的材料加工专业课程思政教学。本文具有一定的理论指导意义和推广价值。

关键词：课程思政教育教学改革材料加工冲压工艺及模具设计

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Rational construction of hollow nanoboxes for long cycle life alkali metal ion batteries

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Journal of Materials Science & Technology 2022年第7期102卷 46-55页

作者： Zheng Zhang Ying Huang Xiang Li zhiming zhou MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions School of Natural and Applied SciencesNorthwestern Polytechnical UniversityXi’an 710072China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of Sciences100 Haike RoadShanghai 201210China

Hollow nanostructures are extremely attractive in energy storage and show broad application *** the preparation method is accompanied by a complicated *** this article,the CoZn-based hol-low nanoboxes with electrochemical synergy are prepared in a simple *** structure can effectively shorten the transmission distance of ions and electrons,and alleviate the volume expansion during the *** particular,bimetallic oxides are rich in oxygen vacancies,providing more active sites for electro-chemical *** addition,the stepwise oxidation-reduction reaction can also improve the volume change of the electrode *** to the kinetic analysis and density functional theory(DFT)calculation,it is confirmed that the synergistic effect of the bimetallic oxide can accelerate the reaction *** on these characteristics,the electrode exhibits stable cycle performance and long cycle life in alkali metal ion batteries,and can provide reversible capacities of 302.1(LIBs,2000 cycles),172.5(SIBs,10000 cycles)and 109.6(PIBs,5000 cycles)mA h g^(-1)at a current density of 1.0 A g^(-1),*** ad-dition,by assembling(LiCoO_(2)//CoZn-O_(2))and(Na_(3)V_(2)(PO_(4))_(3)//CoZn-O_(2))full-cells,the practical application value is *** sharing of this work introduces a simple way to synthesize hollow nanoboxes,and shows excellent electrochemical performance,which can also be expanded in other areas.

关键词： Hollow nanoboxes Bimetallic oxides DFT calculation Alkali metal ion batteries

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Molecular reconstruction of vacuum gas oils using a general molecule library through entropy maximization

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Chinese Journal of Chemical Engineering 2022年第8期35卷 21-29页

作者： Na Wang Chong Peng Zhenmin Cheng zhiming zhou School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Dalian Research Institute of Petroleum and Petrochemicals SINOPECDalian 116000China

Vacuum gas oil(VGO)is the most important feedstock for hydrocracking processes in refineries,but its molecular composition cannot be fully acquired by current analysis techniques owing to its *** order to build an accurate and reliable molecular-level kinetic model for reactor design and process optimization,the molecular composition of VGO has to be reconstructed based on limited *** this study,a modified stochastic reconstruction-entropy maximization(SR-REM)algorithm was applied to reconstruct VGOs,with generation of a general molecule library once and for all via the SR method at the first step and adjustment of the molecular abundance of various VGOs via the REM method at the second *** universality of the molecule library and the effectiveness of the modified SR-REM method were validated by fifteen VGOs(three from the literature)from different geographic regions of the world and with different *** simulated properties(density,elemental composition,paraffin-naphthene-aromatics distribution,boiling point distribution,detailed composition of naphthenes and aromatics in terms of ring number as well as composition of S-heterocycles)are in good agreement with the measured counterparts,showing average absolute relative errors of below 10%for each property.

关键词： Vacuum gas oil Molecular reconstruction Model Algorithm Optimization

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