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Understanding adversarial attacks on observations in deep reinforcement learning

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Science China(Information Sciences) 2024年第5期67卷 69-83页

作者： you QIAOBEN Chengyang YING Xinning ZHOU Hang SU jun ZHU Bo ZHANG Department of Computer Science and Technology Beijing National Research Center for Information Science and Technology Tsinghua-Bosch Joint Center for Machine Learning Institute for Artificial Intelligence Tsinghua University Peng Cheng Laboratory

Deep reinforcement learning models are vulnerable to adversarial attacks that can decrease the cumulative expected reward of a victim by manipulating its observations. Despite the efficiency of previous optimization-based methods for generating adversarial noise in supervised learning, such methods might not achieve the lowest cumulative reward since they do not generally explore the environmental ***, a framework is provided to better understand the existing methods by reformulating the problem of adversarial attacks on reinforcement learning in the function space. The reformulation approach adopted herein generates an optimal adversary in the function space of targeted attacks, repelling them via a generic two-stage framework. In the first stage, a deceptive policy is trained by hacking the environment and discovering a set of trajectories routing to the lowest reward or the worst-case performance. Next, the adversary misleads the victim to imitate the deceptive policy by perturbing the observations. Compared to existing approaches, it is theoretically shown that our adversary is strong under an appropriate noise level. Extensive experiments demonstrate the superiority of the proposed method in terms of efficiency and effectiveness, achieving state-of-the-art performance in both Atari and MuJoCo environments.

关键词： deep learning reinforcement learning adversarial robustness adversarial attack

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拉普拉斯概率论的衰落

自然辩证法研究 2007年第3期23卷 100-103页

作者：王幼军上海师范大学哲学系上海200234

作为概率论历史中一个重要发展阶段的拉普拉斯概率论在20世纪初期走到了它的尽头。从19世纪初开始的关于概率论在法律判决中应用的争论、柯西的“新数学”的兴起及其对最小二乘法的责难、对拉普拉斯概率论基础的批评以及公理化概率论的... 详细信息

作为概率论历史中一个重要发展阶段的拉普拉斯概率论在20世纪初期走到了它的尽头。从19世纪初开始的关于概率论在法律判决中应用的争论、柯西的“新数学”的兴起及其对最小二乘法的责难、对拉普拉斯概率论基础的批评以及公理化概率论的产生等四个方面的讨论,展示了拉普拉斯概率论衰落的历史轮廓。

关键词：拉普拉斯概率论数学史

Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin

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Petroleum Science 2024年第1期21卷 87-99页

作者： Yan-Nan Du Kong-you Wu Yin Liu Yan-Ying Li Zi-Cheng Cao you-Wei Cui jun Liu Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina Exploration and Development Research Institute SINOPEC Northwest Oilfield BranchUrumqi 830011XinjiangChina The Fifth Gas Production Plant Changqing OilfieldPetroChinaXi'an 710018ShaanxiChina

With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention *** by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related *** contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon *** this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim ***-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic ***,the stress state of each point of the STGs was calculated using seismic curvature ***,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were *** results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped *** STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both *** shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient *** study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area.

关键词： Tarim Basin Sigmoidal tension gashes Seismic attributes Shear stress calculation Formation mechanism Reservoir control

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帕斯卡尔的数学心路历程

自然辩证法研究 2017年第4期33卷 73-76页

作者：王幼军上海师范大学哲学与法政学院上海200234

帕斯卡尔在少年时代深受以梅森为代表的巴黎数学家团体的思想影响,他对上帝是一位至高无上的数学家深信不疑,数学研究是其信仰的一部分,这种认识奠定了其数学生涯和精神生活的基础。在其青年时期,基于早期形成的宗教数学观,他的数学探... 详细信息

帕斯卡尔在少年时代深受以梅森为代表的巴黎数学家团体的思想影响,他对上帝是一位至高无上的数学家深信不疑,数学研究是其信仰的一部分,这种认识奠定了其数学生涯和精神生活的基础。在其青年时期,基于早期形成的宗教数学观,他的数学探索热情和创造力达到了高峰,但与此同时,詹森主义者对于数学之于信仰的价值的质疑以及德·梅勒对于数学的确定性及应用的局限性的质问促使了他对于数学的反思。在其短暂一生的后期,他对数学的思考更多地集中于对数学的本质、方法和价值等问题上,尤其集中于数学与基督教信仰的关系上,对于此时的他而言,数学正是人作为被造物所具有的局限性且又试图追求完美和自我超越的这种悖论处境的反映。

关键词：帕斯卡尔数学观宗教信仰

Calculation of ligand-field and Stark sub-levels in laser crystals Nd^(3+):KY(WO_4)_2 and Nd^(3+):KGd(WO_4)_2

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Chinese Journal of Chemistry 1992年第4期10卷 289-294页

作者： wang,Jian-jun you,Xiao-Zeng DAI,An-Bang Coordination Chemistry Institute,Nanjing University,Nanjing,Jiangsu 210008 School of Medicine,Nanjing University,Nanjing,Jiangsu 210008 Coordination Chemistry Institute Nanjing University Nanjing Jiangsu 210008

The parameters of ligand field of laser crystal Na^(3+):KY(WO_4)_2 and Nd^(3+):KGd(WO_4)_2 are obtained by a scheme which involved intermediate coupling and ligand field *** calculated Stark-levels are in good agreeme... 详细信息

关键词： Stark WO4 KGd KY and Nd

Clinical experience sharing on gastric microneuroendocrine tumors: A case report

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World Journal of Clinical Cases 2024年第4期12卷 795-800页

作者： you-jun wang Da-Ming Fan Yu-Shuang Xu Qi Zhao Zhen-Fang Li Department of Gastroenterology Central Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina Department of Pathology Central Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina Department of Gastroenterology The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

BACKGROUND The majority of gastric neuroendocrine tumors(G-NENs)are present in various lesions under endoscopy,and they can be polypoid uplifts,submucosal tumors or papules,erosions,and *** lesions are mostly confined to the mucosal or submucosal layer,usually less than 2 cm,and exclusively localized to the gastric body or *** type 1 G-NENs,about 22%of cases have no visible lesions under an endoscope,and such lesions can only be detected via biopsies(microcar-cinoids).CONCLUSION In the case under study,the patient did not have any visible raised lesions under a gastroscope,and the lesions were found only after a random *** article combines the endoscopic manifestations and clinical features of the lesions in this case to improve the diagnosis of G-NENs.

关键词： Neuroendocrine tumor Micro carcinoids Endoscopy Case report

Activatable fluorescent probes for imaging and diagnosis of rheumatoid arthritis

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Military Medical Research 2024年第2期11卷 287-307页

作者： Pan Luo Fu-Qiang Gao Wei Sun jun-you Li Cheng wang Qing-Yu Zhang Zhi-Zhuo Li Peng Xu Department of Joint Surgery Honghui HospitalXi'an Jiaotong UniversityXi'an 710054China Department of Orthopedics China-Japan Friendship HospitalBeijing 100029China Department of Orthopaedic Surgery of the Perelman School of Medicine University of PennsylvaniaPhiladelphiaPA 19104USA School of Mechanical Engineering Sungkyunkwan UniversitySuwon 16419South Korea Department of Orthopaedic Surgery Peking University Third HospitalPeking UniversityBeijing 100191China Department of Orthopedics Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China State Key Laboratory of Pharmaceutical Biotechnology Division of Sports Medicine and Adult Reconstructive SurgeryDepartment of Orthopedic SurgeryNanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China

Rheumatoid arthritis(RA)is a systemic autoimmune disease that is primarily manifested as synovitis and polyarticular opacity and typically leads to serious joint damage and irreversible disability,thus adversely affecting locomotion ability and life ***,good prognosis heavily relies on the early diagnosis and effective therapeutic monitoring of *** fluorescent probes play vital roles in the detection and imaging of biomarkers for disease diagnosis and in vivo ***,we review the fluorescent probes developed for the detection and imaging of RA biomarkers,namely reactive oxygen/nitrogen species(hypochlorous acid,peroxynitrite,hydroxyl radical,nitroxyl),pH,and cysteine,and address the related challenges and prospects to inspire the design of novel fluorescent probes and the improvement of their performance in RA studies.

关键词： Rheumatoid arthritis Fluorescent probe Imaging Diagnosis Biomarker

Vision-based survey method for extraordinary loads on buildings

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 815-831页

作者： Yang LI jun CHEN Pengcheng wang College of Civil Engineering Tongji UniversityShanghai 200092China China United Engineering Co.Ltd. Hangzhou 310052China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Engineering Structure Safety Shanghai Research Institute of Building Sciences Co.Ltd.Shanghai 200032China

The statistical modeling of extraordinary loads on buildings has been stagnant for decades due to the laborious and error-prone nature of existing survey methods,such as questionnaires and verbal *** study proposes a new vision-based survey method for collecting extraordinary load data by automatically analyzing surveillance *** this purpose,a crowd head tracking framework is developed that integrates crowd head detection and reidentification models based on convolutional neural networks to obtain head trajectories of the crowd in the survey *** crowd head trajectories are then analyzed to extract crowd quantity and velocities,which are the essential factors for extraordinary *** survey areas with frequent crowd movements during temporary events,the equivalent dynamic load factor can be further estimated using crowd velocity to consider dynamic effects.A crowd quantity investigation experiment and a crowd walking experiment are conducted to validate the proposed survey *** experimental results prove that the proposed survey method is effective and accurate in collecting load data and reasonable in considering dynamic effects during extraordinary *** proposed survey method is easy to deploy and has the potential to collect substantial and reliable extraordinary load data for determining design load on buildings.

关键词： load survey extraordinary load live load object detection multiple-object tracking

Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance

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Nano-Micro Letters 2024年第7期16卷 281-294页

作者： Yu-Ying Shi Si-Yuan Liao Qiao-Feng wang Xin-Yun Xu Xiao-Yun wang Xin-Yin Gu you-Gen Hu Peng-Li Zhu Rong Sun Yan-jun Wan Shenzhen Institute of Advanced Electronic Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Southern University of Science and Technology Shenzhen 518055People’s Republic of China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China

The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)***,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of ***,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)*** Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube *** a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),***,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless *** innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices.

关键词： EMI shielding Mechanical strength Carbon nanotubes Metal-organic decomposition Flexibility