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Measuring Policy Performance in Online Pricing with Offline Data:Worst-case Perspective and Bayesian Perspective

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Journal of Systems Science and Systems Engineering 2023年第3期32卷 352-371页

作者： Yue Wang zeyu zheng Department of Computational Medicine University of CaliforniaLos AngelesCA 90095USA Institut des Hautes Etudes Scientifiques Bures-sur-YvetteEssonne 91440France Department of Industrial Engineering and Operations Research University of CaliforniaBerkeleyCA 94720USA

The problems of online pricing with offline data,among other similar online decision making with offline data problems,aim at designing and evaluating online pricing policies in presence of a certain amount of existing offline data.To evaluate pricing policies when offline data are available,the decision maker can either position herself at the time point when the offline data are already observed and viewed as deterministic,or at the time point when the offline data are not yet generated and viewed as stochastic.We write a framework to discuss how and why these two different positions are relevant to online policy evaluations,from a worst-case perspective and from a Bayesian perspective.We then use a simple online pricing setting with offline data to illustrate the constructions of optimal policies for these two approaches and discuss their differences,especially whether we can decompose the searching for the optimal policy into independent subproblems and optimize separately,and whether there exists a deterministic optimal policy.

关键词： Online pricing offline data performance measure worst-case approach Bayesian approach

Strain engineering of Pt-based electrocatalysts for oxygen reaction reduction

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Frontiers in Energy 2024年第2期18卷 241-262页

作者： zeyu WANG Yanru LIU Shun CHEN Yun zheng Xiaogang FU Yan ZHANG Wanglei WANG State Key Laboratory of Solidification Processing Atomic Control and Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of Dental MaterialsSchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032China Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China

Proton exchange membrane fuel cells(PEMFCs)are playing irreplaceable roles in the construction of the future sustainable energy system.However,the insufficient performance of platinum(Pt)-based electrocatalysts for oxygen reduction reaction(ORR)hinders the overall efficiency of PEMFCs.Engineering the surface strain of catalysts is considered an effective way to tune their electronic structures and therefore optimize catalytic behavior.In this paper,insights into strain engineering for improving Pt-based catalysts toward ORR are elaborated in detail.First,recent advances in understanding the strain effects on ORR catalysts are comprehensively discussed.Then,strain engineering methodologies for adjusting Ptbased catalysts are comprehensively discussed.Finally,further information on the various challenges and potential prospects for strain modulation of Pt-based catalysts is provided.

关键词： strain engineering Pt-based catalysts oxygen reduction reaction(ORR) catalytic performance proton exchange membrane fuel cells(PEMFCs)

Detecting the spatial-temporal pattern of moisture evolution on the Tibetan Plateau during the Holocene by model-proxy comparison

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Frontiers of Earth Science 2023年第4期17卷 981-996页

作者： zeyu zheng Liya JIN Jinjian LI Xiaojian ZHANG Jie CHEN MOE Key Laboratory of Western China’s Environmental System College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China

The Tibetan Plateau(TP)is a key region for environmental and climatic research due to its significant linkages with large-scale atmospheric circulation.Understanding the long-term moisture evolution pattern and its forcing mechanisms on the TP during the Holocene may provide insights into the interaction between low-latitude climate systems and midlatitude westerlies.Here,we synthesized 27 paleoclimate proxy records covering the past 9500 years.The results of the rotated empirical orthogonal function analysis of the moisture variation revealed spatial-temporal heterogeneity,which was classified into 5 subregions.Proxy records were then compared with the results from the Kiel Climate Model and other paleorecords.The results showed that moisture evolution on the western-southern-central TP was controlled by the Indian summer monsoon(ISM).On the south-eastern TP,moisture change was affected by the interplay between the East Asian summer monsoon(EASM)and the westerlies,as well as the ISM.With diverse patterns of circulation system precipitation,moisture changes recorded in the paleorecords showed spatial-temporal discrepancies,especially during the early to middle Holocene.Moreover,given the anti-phase pattern of summer precipitation in the EASM area under El Nino/Southern Oscillation(ENSO)conditions and the unstable relationship between the ISM and ENSO,it is reasonable to conclude that relatively strong ENSO variability during the late Holocene has contributed to these discrepancies as Asian summer monsoon precipitation has declined.

关键词： Tibetan Plateau Holocene moisture evolution model-proxy comparison

自然资源资产收益中央-地方分配机制的规范建构

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中国人口·资源与环境 2024年第4期34卷 150-160页

作者：郑泽宇山东科技大学文法学院山东青岛266590

自然资源资产收益中央-地方(以下简称央地)分配机制的合理建构对于理顺央地自然资源收益主体关系、落实自然资源国家所有者权益、提升自然资源开发区域生态补偿能力、促成自然资源资产收益在央地两级层面的规模增长和科学利用具有积极... 详细信息

自然资源资产收益中央-地方(以下简称央地)分配机制的合理建构对于理顺央地自然资源收益主体关系、落实自然资源国家所有者权益、提升自然资源开发区域生态补偿能力、促成自然资源资产收益在央地两级层面的规模增长和科学利用具有积极意义。在现行制度表征上,自然资源资产收益央地分配机制的实施依托于央地分权的自然资源资产管理框架,并呈现出地方收益为主的规制结构。在这一规制结构下,一方面,央地自然资源资产管理事权、自然资源资产管护职责无法与收益分配结果相衔接,造成央地自然资源资产管理权责利的失衡;另一方面,制约了自然资源资产收益的国家宏观调控能力,导致国家所有权收益缺失,增加了地方“资源诅咒”经济增长和资源收益区域间配置不均衡的风险。收益央地分配机制需要规范建构,旨在通过收益分配实现央地自然资源资产管理的权责对等和利益均衡。在路径上,以优化调整央地自然资源资产管理事权关系为起手,以确立中央主导支配的自然资源资产收益机制为过程,以建立基于事权划分的央地收益弹性管理机制为结果,通过央地权责一体连结机制、权责弹性划分机制、收益地方弹性留存机制、收益央地横纵向流动机制和地方留存收益科学管理机制的实施,确保自然资源资产收益在央地分配层面的秩序和效益。

关键词：自然资源资产收益中央-地方分配中央-地方关系规范建构

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农村环境简约治理:内涵机理和实践路径

学习与实践 2024年第1期 64-75页

作者：郑泽宇山东科技大学文法学院山东青岛266590

当前农村环境治理在复杂治理和规模治理的体制惯性中引发要素过密、机制掣肘、协商难度加大、行政成本攀升、治理资源浪费等一系列问题,亟需“化繁为简”的改制创新。简约治理具有简化组织流程结构、精准资源投入靶向和统合非科层化治... 详细信息

当前农村环境治理在复杂治理和规模治理的体制惯性中引发要素过密、机制掣肘、协商难度加大、行政成本攀升、治理资源浪费等一系列问题,亟需“化繁为简”的改制创新。简约治理具有简化组织流程结构、精准资源投入靶向和统合非科层化治理力量的灵活、高效和低成本优势,是革新农村环境治理模式的可行思路。同时,推进农村环境简约治理面临着科层治理权力行使“悬浮”、正式规则密集约束、治理资源错配和目标错位的现实挑战。应明确治理资源投入靶向,精简政府管控职能,简化正式规则运作体系,凝聚多元主体治理目标,培育农村环境非正式治理机制,以此构建农村环境简约治理的实践体系。

关键词：农村环境治理正式规则简约治理非正式治理机制

Small-molecule agents for cancer immunotherapy

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Acta Pharmaceutica Sinica B 2024年第3期14卷 905-952页

作者： Fang Wang Kai Fu Yujue Wang Can Pan Xueping Wang zeyu Liu Chuan Yang Ying zheng Xiaopeng Li Yu Lu Kenneth Kin Wah To Chenglai Xia Jianye Zhang Zhi Shi Zeping Hu Min Huang Liwu Fu State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineGuangdong Esophageal Cancer InstituteGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060China School of Pharmaceutical Sciences Tsinghua-Peking Center for Life SciencesBeijing Frontier Research Center for Biological StructureTsinghua UniversityBeijing 100084China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Department of Cell Biology&Institute of Biomedicine National Engineering Research Center of Genetic MedicineMOE Key Laboratory of Tumor Molecular BiologyGuangdong Provincial Key Laboratory of Bioengineering MedicineCollege of Life Science and TechnologyJinan UniversityGuangzhou 510632China Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target&Clinical Pharmacology NMPA and State Key Laboratory of Respiratory DiseaseSchool of Pharmaceutical Sciences and the Fifth Affiliated HospitalGuangzhou Medical UniversityGuangzhou 511436China School of Pharmacy The Chinese University of Hong KongHong Kong 999077China Affiliated Foshan Maternity and Child Healthcare Hospital Southern Medical UniversityFoshan 528000China

Cancer immunotherapy,exemplified by the remarkable clinical benefits of the immune checkpoint blockade and chimeric antigen receptor T-cell therapy,is revolutionizing cancer therapy.They induce long-term tumor regression and overall survival benefit in many types of cancer.With the advances in our knowledge about the tumor immune microenvironment,remarkable progress has been made in the development of small-molecule drugs for immunotherapy.Small molecules targeting PRR-associated pathways,immune checkpoints,oncogenic signaling,metabolic pathways,cytokine/chemokine signaling,and immune-related kinases have been extensively investigated.Monotherapy of smallmolecule immunotherapeutic drugs and their combinations with other antitumor modalities are under active clinical investigations to overcome immune tolerance and circumvent immune checkpoint inhibitor resistance.Here,we review the latest development of small-molecule agents for cancer immunotherapy by targeting defined pathways and highlighting their progress in recent clinical investigations.

关键词： Cancer immunotherapy Small-molecule agents Immune checkpoints Oncogenic signaling Metabolic pathways Cytokine/chemokine signaling Antitumor immunity Tumor immune microenvironment

Designing mechanically tough graphene oxide materials using deep reinforcement learning

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npj Computational Materials 2022年第1期8卷 2139-2147页

作者： Bowen zheng zeyu zheng Grace X.Gu Department of Mechanical Engineering University of CaliforniaBerkeleyCA94720USA Department of Industrial Engineering and Operations Research University of CaliforniaBerkeleyCA94720USA

Graphene oxide(GO)is playing an increasing role in many technologies.However,it remains unanswered how to strategically distribute the functional groups to further enhance performance.We utilize deep reinforcement learning(RL)to design mechanically tough GOs.The design task is formulated as a sequential decision process,and policy-gradient RL models are employed to maximize the toughness of GO.Results show that our approach can stably generate functional group distributions with a toughness value over two standard deviations above the mean of random GOs.In addition,our RL approach reaches optimized functional group distributions within only 5000 rollouts,while the simplest design task has 2×10^(11)possibilities.Finally,we show that our approach is scalable in terms of the functional group density and the GO size.The present research showcases the impact of functional group distribution on GO properties,and illustrates the effectiveness and data efficiency of the deep RL approach.

关键词： toughness tough oxide

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基于混合现实的可移动机械臂操作控制系统

激光与光电子学进展 2024年第4期61卷 271-279页

作者：董泽宇刘政李勇胡立坤广西大学电气工程学院广西南宁530004

为应对特殊条件下不便于实地进行移动式操作的问题,设计了一套基于混合现实的可移动机械臂操作控制系统。该系统分为人机交互、机械驱动、虚拟现实等3个模块:人机交互模块通过摄像头识别操作者肢体手势动作并发布相应操作指令;机械驱动... 详细信息

为应对特殊条件下不便于实地进行移动式操作的问题,设计了一套基于混合现实的可移动机械臂操作控制系统。该系统分为人机交互、机械驱动、虚拟现实等3个模块:人机交互模块通过摄像头识别操作者肢体手势动作并发布相应操作指令;机械驱动模块解析由人机交互模块发布的操作指令后完成相应动作并反馈设备工作状态;虚拟现实模块接收机械驱动模块反馈信息后将设备运行情况在构建好的虚拟场景中还原,实现对设备运行情况的实时监控。在可移动机械臂平台上的测试结果表明,操作者通过所提系统可以实现对可移动机械臂的远程精准控制与实时监控,系统响应速度能够达到60~100 ms/frame。

关键词：机器视觉混合现实 Unity3D 机械臂动作捕捉

植酸修饰改性对TC4钛合金微弧氧化膜层性能的影响

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稀有金属材料与工程 2024年第4期53卷 954-962页

作者：兰欣悦王平龚泽宇罗许郑友平邓博文钒钛资源综合利用国家重点实验室四川攀枝花607000 西南石油大学新能源与材料学院四川成都610500 中国科学院大学中国科学院化学研究所北京100190

通过向电解液中添加有机酸植酸,提升了TC4钛合金微弧氧化涂层的耐腐蚀性能和热稳定性。通过扫描电子显微镜、X射线衍射仪、X射线光电子能谱仪和热冲击实验等技术手段,分析了植酸对涂层形成、形貌和性能的影响。结果显示,植酸的添加使放... 详细信息

通过向电解液中添加有机酸植酸,提升了TC4钛合金微弧氧化涂层的耐腐蚀性能和热稳定性。通过扫描电子显微镜、X射线衍射仪、X射线光电子能谱仪和热冲击实验等技术手段,分析了植酸对涂层形成、形貌和性能的影响。结果显示,植酸的添加使放电微孔更加细小,提高了涂层的形成效率并优化了相结构。通过动电位极化测试,发现添加植酸显著提高了微弧氧化涂层的耐腐蚀性能。将电解液中的植酸浓度调整为12 m L/L(最佳植酸浓度)后,腐蚀电流密度由8.406×10^(-5)A·cm^(-2)降低至2.580×10^(-6)A·cm^(-2)。循环高温氧化试验结果表明,TC4钛合金的耐热冲击性能和高温抗氧化性能得到了改善。

关键词： TC4钛合金微弧氧化耐腐蚀性能耐热冲击性能