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Controlling underestimation bias in reinforcement learning via minmax operation

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Chinese Journal of Aeronautics 2024年第7期37卷 406-417页

作者： Fanghui huang Yixin HE yu ZHANG Xinyang DENG wen JIANG School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China College of Information Science and Engineering Jiaxing UniversityJiaxing 314001China

Obtaining the accurate value estimation and reducing the estimation bias are the key issues in reinforcement ***,current methods that address the overestimation problem tend to introduce underestimation,which face a challenge of precise decision-making in many *** address this issue,we conduct a theoretical analysis of the underestimation bias and propose the minmax operation,which allow for flexible control of the estimation ***,we select the maximum value of each action from multiple parallel state-action networks to create a new state-action value ***,a minimum value is selected to obtain more accurate value ***,based on the minmax operation,we propose two novel algorithms by combining Deep Q-Network(DQN)and Double DQN(DDQN),named minmax-DQN and ***,we conduct theoretical analyses of the estimation bias and variance caused by our proposed minmax operation,which show that this operation significantly improves both underestimation and overestimation biases and leads to the unbiased ***,the variance is also reduced,which is helpful to improve the network training ***,we conduct numerous comparative experiments in various environments,which empirically demonstrate the superiority of our method.

关键词： Reinforcement learning Minmax operation Estimation bias Underestimation bias Variance

Air target intention recognition and causal effect analysis combining uncertainty information reasoning and potential outcome framework

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Chinese Journal of Aeronautics 2024年第1期37卷 287-299页

作者： yu ZHANG Fanghui huang Xinyang DENG Mingda LI wen JIANG School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

Recognizing target intent is crucial for making decisions on the ***,the imperfect and ambiguous character of battlefield situations challenges the validity and causation analysis of classical intent recognition *** with the challenge,a target intention causal analysis paradigm is proposed by combining with an Intervention Retrieval(IR)model and a Hybrid Intention Recognition(HIR)*** target data acquired by the sensors are modelled as Basic Probability Assignments(BPAs)based on evidence theory to create uncertain ***,the HIR model is utilized to recognize intent for a tested sample from uncertain ***,the intervention operator under the evidence structure is utilized to perform attribute intervention on the tested *** retrieval is performed in the sample database based on the IR model to generate the intention distribution of the pseudo-intervention samples to analyze the causal effects of individual sample *** simulation results demonstrate that our framework successfully identifies the target intention under the evidence structure and goes further to analyze the causal impact of sample attributes on the target intention.

关键词： Causal effect analysis Hybrid intention recognition Intervention retrieval Target intention Uncertainty reasoning

BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

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Nuclear Science and Techniques 2024年第7期35卷 68-78页

作者： Zhi-Jun Wang Si-Sheng Wang Zheng-huang Su Li yu yu-Zhu Wang Bo Sun wen wen Xing-yu Gao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Science Beijing100049China

A Laue microdiffraction beamline(BL03HB) was constructed at the Shanghai Synchrotron Radiation Facility(SSRF).This beamline features two consecutive focusing points in two different sectors within its end station, the first dedicated to protein crystallography and the other tailored to materials science applications. Based on a superbend dipole magnet with a magnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick-Baez mirrors to achieve a micro white beam as small as 4.2 μ m ×4.3 μ m at the first sector and 0.9 μ m ×1.3 μ m at the second sector in the standard beamline operation mode at SSRF. The X-ray microbeam in the two sectors can be easily switched between monochromatic and white beams by moving a four-bounce monochromator in or out of the light path, respectively. In the protein crystallography sector, white-beam Laue microdiffraction was demonstrated to successfully determine the structure of protein crystals from only a few images of diffraction data collected by a Pilatus 2 M area detector. In the materials science sector,the white-beam Laue diffraction was collected in a reflection geometry using another Pilatus 2 M area detector, which could map the microstructural distribution on the sample surface by scanning the samples. In general, the BL03HB beamline promotes the application of Laue microdiffraction in both protein crystallography and materials science. This paper presents a comprehensive overview of the BL03HB beamline, end station, and the first commission results.

关键词： Crystallography White-beam Laue microdiffraction Beamline Synchrotron

Diagnostic value associated with the combination of saliva pepsin and microorganisms in functional heartburn and gastroesophageal reflux disease

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World Journal of Gastroenterology 2024年第19期30卷 2612-2614页

作者： yu-Qi huang Chao Yang wen Luo Department of Stomatology The First Affiliated Hospital of Hainan Medical UniversityHaikou 570102Hainan ProvinceChina School of Stomatology Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Research and Development Department Shenzhen Uni-medica Technology Co.LtdShenzhen 518051Guangdong ProvinceChina Department of Stomatology The People’s Hospital of LonghuaShenzhen 518109Guangdong ProvinceChina

Heartburn is a common symptom shared by both gastroesophageal reflux disease(GERD)and functional heartburn(FHB),which can make it challenging to differentiate between the two ***,examining oral manifestations of GERD can be a cost-effective and readily available method to aid in this differentiation *** may serve as a valuable tool in distinguishing GERD from FHB.

关键词： Gastroesophageal reflux disease Gastric acid Heartburn Differential diagnosis Epidemiology Oral manifestations Prevalence Risk factors Dental erosion Periodontal diseases

Preliminary Evaluation of Cloud Fraction Simulations by GAMIL2 Using COSP

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Atmospheric and Oceanic Science Letters 2012年第3期5卷 258-263页

作者： DONG Li LI Li-Juan huang wen-yu WANG Yong WANG Bin State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Dynamics （LASG） Institute of Atmos-pheric Physics （IAP） Chinese Academy of Sciences Beijing 100029 China Ministry of Education Key Laboratory for Earth System Modeling and Center for Earth System Science Tsinghua University Beijing 100084 China

The Cloud Feedback Model Intercomparisons Project (CFMIP) Observation Simulator Package (COSP) is adopted in the Grid-point Atmospheric Model of IAP LASG (GAMIL2) during CFMIP at Phase II to evaluate the model cloud fractions in a consistent way with satellite observations. The cloud simulation results embedded in the Atmospheric Model Intercomparison Project (AMIP) control experiment are presented using three satellite simulators: International Satellite Cloud Climatology Project (ISCCP), Moderate Resolution Imaging Spectroradiometer (MODIS), and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar onboard the Cloud- Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). Overall, GAMIL2 can produce horizontal distributions of the low cloud fraction that are similar to the satellite observations, and its similarities to the observations on different levels are shown in Taylor diagrams. The discrepancies among satellite observations are also shown, which should be considered during evaluation.

关键词： COSP GAMIL cloud fraction satellite simu- lator

Centrifuge study on behavior of raft foundation after tunnelling in soft clay

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Underground Space 2024年第4期17卷 161-169页

作者： Jian yu Jiaming Liu Chun Fai Leung Maosong huang Qi wen Jorgin Tan Department of Geotechnical Engineering Key Laboratory of Geotechnical and Underground Engineering of Ministry of EducationTongji UniversityShanghai 200092China Centre for Offshore Research and Engineering Department of Civil and Environmental EngineeringNational University of Singapore119077Singapore Land Transport Authority 219428Singapore

Ground losses due to tunneling would induce settlement of nearby raft *** study the change in behavior of the raft foundations over time due to tunnel excavation in soft clay,a series of centrifuge model tests were *** results reveal that the raft stiffness has a significant influence on the development of the gap between the raft and the *** width of the gap beneath the flexible foundation would increase over time,leading to a further increase in tensile strain after excavation,whereas the gap for raft foundations with a large stiffness would reduce with time,causing a gradual decrease in tensile *** modification factor(MF)design approach is also evaluated with the test results and demonstrates that the MF design approach would underestimate the tensile strain of the flexible raft and provide a relatively conservative prediction for larger stiffnesses.

关键词： Tunnelling Raft Clay Deflection ratio Centrifuge test

An optimal flow rate allocation model of the oilfield treated oil pipeline network

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Petroleum 2024年第1期10卷 93-100页

作者： Hai Li Tianyou Fan Kun Wang Xueyuan Long yu He Meng Wang wen Cheng Qian huang Huirong huang Weichao yu PetroChina Southwest Oil&Gasfield Company Chengdu 610056China China Petroleum Planning&Engineering Institute Beijing 100083China School of Petroleum Engineering Chongqing University of Science and TechnologyChongqing 401331China PipeChina Oil&Gas Control Center Dongtucheng RoadChaoyang DistrictBeijing 100028China

Oilfield treated oil pipeline network is the link connecting the upstream oilfields and the downstream *** to the differences in operating costs and transportation fee between different pipelines and the fluctuation in the demand and sales prices of the treated oil,there is an optimal flow allocation plan for the pipeline network to make the oilfield company obtain the highest social and economic *** this study,a mixed integer nonlinear programming(MINLP)model is developed to determine the optimal flow rate allocation plan of the large-scale and complex treated oil pipeline network,and both the social and economic benefits are considered *** optimization objective is the multi-objective which includes the largest user satisfaction and the highest economic *** model constraints include the oilfield production capacity,refinery demand,pipeline transmission capacity,flow,pressure,and temperature of the node and station,and the pipeline hydraulic and thermal *** 3.7 is utilized for the programming of the off-line calculation procedure and the MINLP model,and GUROBI 9.0.2 is served as the MINLP ***,the model is applied to a real treated oil pipeline network located in China,and three optimization scenarios are *** social benefit,the values of the user satisfaction of each refinery and the total network are 1 before and after optimization for scenarios 1,2,and *** economic benefit,the annual revenue can be increased by 0.227,0.293,and 0.548 billion yuan after the optimization in scenario 1,2,and 3,respectively.

关键词： Treated oil pipeline network Flow rate allocation Optimal User satisfaction Economic benefit

Novel high-voltage cathode for aqueous zinc ion batteries:Porous K_(0.5)VOPO_(4)·1.5H_(2)O with reversible solid-solution intercalation and conversion storage mechanism

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Journal of Energy Chemistry 2024年第6期93卷 71-78,I0003页

作者： Liyu Wang Mingliang Zhao Xiaoyu Zhang Menghua Wu yu Zong yu Chen Xinliang huang Mingjie Xing Xin Ning wen wen Daming Zhu Xiaochuan Ren Industrial Research Institute of Nonwovens&Technical Textiles College of Textiles&ClothingShandong Engineering Research Center for Specialty Nonwoven MaterialsQingdao UniversityQingdao 266071ShandongChina Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Cathode materials that possess high output voltage,as well as those that can be mass-produced using facile techniques,are crucial for the advancement of aqueous zinc-ion battery(ZIBs)applications,Herein,we present for the first time a new porous K_(0.5)VOPO_(4)·1.5H_(2)O polyanionic cathode(P-KIVP)with high output voltage(above 1.2 V)that can be manufactured at room temperature using straightforward coprecipitation and etching *** P-KVP cathode experiences anisotropic crystal plane expansion via a sequential solid-solution intercalation and phase co nversion pathway throughout the Zn^(2+)storage process,as confirmed by in-situ synchrotron X-ray diffraction and ex-situ X-ray photoelectron *** to other layered vanadium-based polyanionic materials,the P-KVP cathode experiences a progressive decline in voltage during the cycle,which is demonstrated to be caused by the irreversible conversion into amorphous VO_(x).By introducing a new electrolyte containing Zn(OTF)_(2) to a mixed triethyl phosphate and water solution,it is possible to impede this irreversible conversion and obtain a high output voltage and longer cycle life by forming a P-rich cathode electrolyte interface *** a proof-of-concept,the flexible fiber-shaped ZIBs based on modified electrolyte woven into a fabric watch band can power an electronic watch,highlighting the application potential of P-KVP cathode.

关键词： Aqueous zinc ion battery Cathode Porous material High voltage platform In-situ synchrotron X-ray diffraction

Ferroelectric-controlled graphene plasmonic surfaces for all-optical neuromorphic vision

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Science China(Technological Sciences) 2024年第3期67卷 765-773页

作者： CHEN JianBo LIU yu LI ShangDong LIN Lin LI YaDong huang wen GUO JunXiong School of Electronic Information and Electrical Engineering Institute for Advanced StudyChengdu UniversityChengdu 610106China School of Integrated Circuits Tsinghua UniversityBeijing 100084China School of Integrated Circuits(National Exemplary Schoolof Microelectronics) Universityof Electronic Science and Technologyof China Chengdu 610054China Jincheng Research Institute of Opto-mechatronics Industry Jincheng 048000China Shanxi Key Laboratory of Advanced Semiconductor Optoelectronic Devices and Integrated Systems Jincheng 048000China Engineering Research Center of Digital Imaging and Display Ministry of EducationSoochow UniversitySuzhou 215006China

Artificial visual systems can recognize desired objects and information from complex environments, and are therefore highly desired for pattern recognition, object detection, and imaging applications. However, state-of-the-art artificial visual systems with high recognition performances that typically consist of electronic devices face the challenges of requiring huge storage space and high power consumption owing to redundant data. Here, we report a terahertz(THz) frequency-selective surface using a graphene split-ring resonator driven by ferroelectric polarization for efficient visual system applications. The downward polarization of the ferroelectric material offers an ultrahigh electrostatic field for doping p-type graphene with an anticipated Fermi level. By optimizing the geometric parameters of the devices and modulating the carrier behaviors of graphene, our plasmonic devices exhibit a tunable spectral response in a range of 1.7–6.0 THz with continuous transmission values. The alloptical neural network using graphene plasmonic surfaces designed in this study exhibited excellent performance in visual preprocessing and convolutional filtering and achieved an ultrahigh recognition accuracy of up to 99.3% in training the Modified National Institute of Standards and Technology(MNIST) handwritten digit dataset. These features demonstrate the great potential of graphene plasmonic devices for future smart artificial vision systems.

关键词： graphene plasmon ferroelectric frequency selective surface artificial vision system