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Rethinking Polyp Segmentation from An Out-ofdistribution Perspective

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Machine Intelligence Research 2024年第4期21卷 631-639页

作者： Ge-peng Ji jing Zhang Dylan Campbell Huan xiong Nick Barnes Australian National University Canberra 8105Australia Mohamed bin Zayed University of Artificial Intelligence Abu Dhabi 999041UAE

Unlike existing fully-supervised approaches,we rethink colorectal polyp segmentation from an out-of-distribution perspective with a simple but effective self-supervised learning *** leverage the ability of masked autoencoders-self-supervised vision transformers trained on a reconstruction task-to learn in-distribution representations,here,the distribution of healthy colon *** then perform out-of-distribution reconstruction and inference,with feature space standardisation to align the latent distribution of the diverse abnormal samples with the statistics of the healthy *** generate per-pixel anomaly scores for each image by calculating the difference between the input and reconstructed images and use this signal for out-of-distribution(i.e.,polyp)*** results on six benchmarks show that our model has excellent segmentation performance and generalises across *** code is publicly available at https://***/GewelsJI/Polyp-OOD.

关键词： Polyp segmentation anomaly segmentation out-of-distribution segmentation masked autoencoder abdomen.

Autonomous navigation method of satellite constellation based on adaptive forgetting factors

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Chinese Journal of Aeronautics 2024年第7期37卷 317-332页

作者： Dong WANG jing YANG Kai xiong School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100094China

To address the problem that model uncertainty and unknown time-varying system noise hinder the filtering accuracy of the autonomous navigation system of satellite constellation,an autonomous navigation method of satellite constellation based on the Unscented Kalman Filter with Adaptive Forgetting Factors(UKF-AFF)is *** process noise covariance matrix is estimated online with the strategy that combines covariance matching and adaptive adjustment of forgetting *** adaptive adjustment coefficient based on squared Mahalanobis distance of state residual is employed to achieve online regulation of forgetting factors,equipping this method with more *** intersatellite direction vector obtained from photographic observations is introduced to determine the constellation satellite orbit together with the distance measurement to avoid rank deficiency *** that the number of available measurements varies online with intersatellite visibility in practical applications such as time-varying constellation configurations,the smooth covariance matrix of state correction determined by innovation and gain is adopted and constructed *** analysis of the proposed method is also *** effectiveness of the proposed method is verified by the Monte Carlo simulation and comparison *** estimation accuracy of constellation position and velocity of UKF-AFF is improved by 30%and 44%respectively compared to those of the extended Kalman filter,and the method proposed is also better than other several adaptive filtering methods in the presence of significant model uncertainty.

关键词： Constellation autonomous navigation Unscented Kalman filter Adaptive forgetting factor Model uncertainty Stability analysis

Amino acids in piglet diarrhea:Effects,mechanisms and insights

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Animal Nutrition 2024年第1期16卷 267-274页

作者： Xihong Zhou jing Liang Xia xiong Yulong Yin Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureThe Chinese Academy of SciencesChangsha 410125China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

Piglet diarrhea is among one of the most serious health problems faced by the pig industry,resulting in significant economic *** disease in piglets has a multifactorial etiology that is affected by physiology,environment,and management *** is the most apparent symptom of intestinal *** a key class of essential nutrients in the piglet diet,amino acids confer a variety of beneficial effects on piglets in addition to being used as a substrate for protein synthesis,including maintaining appropriate intestinal integrity,permeability and epithelial renewal,and alleviating morphological damage and inflammatory and oxidative ***,provision of appropriate levels of amino acids could alleviate piglet *** amino acid effects are mediated by metabolites,gut microbes,and related signaling *** this review,we summarize the current understanding of dietary amino acid effects on gut health and diarrhea incidence in piglets,and reveal the mechanisms *** also provide ideas for using amino acid blends and emphasize the importance of amino acid balance in the diet to prevent diarrhea in piglets.

关键词： Piglet Amino acid Diarrhea Gut microbe Immune

Spatial Variation in CO_(2) Concentration Improves the Simulated Surface Air Temperature Increase in the Northern Hemisphere

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Advances in Atmospheric Sciences 2024年第8期41卷 1614-1628,1676-1685页

作者： jing peng Li DAN Xiba TANG CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) Institute of Atmospheric PhysicsBeijing 100029China

The increasing concentration of atmospheric CO_(2) since the Industrial Revolution has affected surface air ***,the impact of the spatial distribution of atmospheric CO_(2) concentration on surface air temperature biases remains highly *** incorporating the spatial distribution of satellite-derived atmospheric CO_(2) concentration in the Beijing Normal University Earth System Model,this study investigated the increase in surface air temperature since the Industrial Revolution in the Northern Hemisphere(NH) under historical conditions from *** comparison with the increase in surface temperature simulated using a uniform distribution of CO_(2),simulation with a nonuniform distribution of CO_(2)produced better agreement with the Climatic Research Unit(CRU) data in the NH under the historical condition relative to the baseline over the period *** June-July-August(JJA) surface air temperature increased by 1.28℃ ±0.29℃ in simulations with a uniform distribution of CO_(2),by 1.00℃±0.24℃ in simulations with a non-uniform distribution of CO_(2),and by 0.24℃ in the CRU *** decrease in downward shortwave radiation in the non-uniform CO_(2) simulation was primarily attributable to reduced warming in Eurasia,combined with feedbacks resulting from increased leaf area index(LAI) and latent heat *** effects were more pronounced in the non-uniform CO_(2)simulation compared to the uniform CO_(2) *** indicate that consideration of the spatial distribution of CO_(2)concentration can reduce the overestimated increase in surface air temperature simulated by Earth system models.

关键词： spatial variations of CO_(2) surface air temperature Earth system model land surface albedo leaf area index

Prediction and scheduling of multi-energy microgrid based on BiGRU self-attention mechanism and LQPSO

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Global Energy Interconnection 2024年第3期7卷 347-361页

作者： Yuchen Duan peng Li jing Xia School of Automation and Intelligence Beijing Jiaotong UniversityBeijing 100044P.R.China Goldwind Science&Technology Co.Ltd. Beijing 100176P.R.China

To predict renewable energy sources such as solar power in microgrids more accurately,a hybrid power prediction method is presented in this ***,the self-attention mechanism is introduced based on a bidirectional gated recurrent neural network(BiGRU)to explore the time-series characteristics of solar power output and consider the influence of different time nodes on the prediction ***,an improved quantum particle swarm optimization(QPSO)algorithm is proposed to optimize the hyperparameters of the combined prediction *** final proposed LQPSO-BiGRU-self-attention hybrid model can predict solar power more *** addition,considering the coordinated utilization of various energy sources such as electricity,hydrogen,and renewable energy,a multi-objective optimization model that considers both economic and environmental costs was constructed.A two-stage adaptive multi-objective quantum particle swarm optimization algorithm aided by a Lévy flight,named MO-LQPSO,was proposed for the comprehensive optimal scheduling of a multi-energy microgrid *** algorithm effectively balances the global and local search capabilities and enhances the solution of complex nonlinear *** effectiveness and superiority of the proposed scheme are verified through comparative simulations.

关键词： Microgrid Bidirectional gated recurrent unit Self-attention Lévy-quantum particle swarm optimization Multi-objective optimization

Recorded recurrent deep reinforcement learning guidance laws for intercepting endoatmospheric maneuvering missiles

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Defence Technology（防务技术） 2024年第1期31卷 457-470页

作者： Xiaoqi Qiu peng Lai Changsheng Gao Wuxing jing Department of Aerospace Engineering Harbin Institute of TechnologyHarbin150001China Shanghai Electro-Mechanical Engineering Institute Shanghai Academy of Spaceflight TechnologyShanghai201100China

This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with uncertainties and observation *** attack-defense engagement scenario is modeled as a partially observable Markov decision process(POMDP).Given the benefits of recurrent neural networks(RNNs)in processing sequence information,an RNN layer is incorporated into the agent’s policy network to alleviate the bottleneck of traditional deep reinforcement learning methods while dealing with *** measurements from the interceptor’s seeker during each guidance cycle are combined into one sequence as the input to the policy network since the detection frequency of an interceptor is usually higher than its guidance *** training,the hidden states of the RNN layer in the policy network are recorded to overcome the partially observable problem that this RNN layer causes inside the *** training curves show that the proposed RRTD3 successfully enhances data efficiency,training speed,and training *** test results confirm the advantages of the RRTD3-based guidance laws over some conventional guidance laws.

关键词： Endoatmospheric interception Missile guidance Reinforcement learning Markov decision process Recurrent neural networks

Interface optimization of graphene paper-Cu composite prepared by electrodeposition

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Journal of Iron and Steel Research(International) 2024年第1期31卷 64-73页

作者： jing Guo Hai-jing Wang Shuang-juan Liu peng Zhang jing-yu Tang Wei-yang Zhang Han-jie Guo peng-cheng Wang Cai Meng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Advanced Technology and Materials Co. Ltd.Beijing100083China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei230027AnhuiChina

A room-temperature electrodeposition method with an organic electrolyte was developed to fabricate a HNO3-pretreated graphene paper Cu(GP'-Cu)*** improve the interfacial bonding of GP'-Cu composite,magnetron sputtering technology was used to create a"sandwich"structural gradient GP'-Cu *** selection of the intermediate transition layer metal was based on two-dimensional *** electron microscopy,X-ray photoelectron spectroscopy,and other analytical methods confirmed that the addition of an intermediate transition metal(Cr,Ni)layer reduced the gap distance and enhanced the interfacial bonding of the GP'and Cu deposited *** GP'-Ni-Cu composite exhibited the largest increase in tensile strength and *** addition,it had the highest thermal diffusivity and elongation at break among the GP'-Cu,GP'-Cr-Cu and GP'-Ni-Cu composites.

关键词： Graphene paper Two-dimensional disregistry Magnetron sputtering Metal composite

Pore shrinkage capacity of Shajiang black soils(Vertisols)on the North China Plain and its influencing factors

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Pedosphere 2024年第3期34卷 620-630页

作者： Yueming CHEN Zhongbin ZHANG Lei GAO Zichun GUO peng xiong Fahui JIANG Xinhua peng State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Jiangxi Agricultural University Nanchang 330045(China)

Different pore sizes present different pore shrinkage capacities in a nonrigid ***,the shrinkage capacities of different pore sizes and their influencing factors are not *** aimed to quantify the shrinkage capacities of different pore sizes(large pores,>50μm;medium pores,0.2-50μm;fine pores,<0.2μm)and determine how soil properties impact soil shrinkage capacity at the regional *** sampling transects from west to east(360 km long,35 samples)and from north to south(190 km long,29 samples)were selected to investigate soil shrinkage capacity and physicochemical properties of at0-20 cm depth in the Vertisol(locally known as Shajiang black soil)region of the North China *** results showed that soil total shrinkage capacity,indicated by the coefficient of linear extensibility(COLE),had a mean value of 0.041-0.051 in the west-east and north-south *** pores had higher pore shrinkage index(PSI)values(0.103-0.109)than medium(0.077-0.096)and fine(0.087-0.091)*** PSI of fine pores showed a fluctuating increasing trend from northwest to southeast,and the fine pore shrinkage capacity determined the COLE(r^(2)=0.789,P<0.001).The PSI of large pores had a significant relationship with soil bulk density(r=0.281,P<0.05)and organic carbon(r=-0.311,P<0.05),whereas those of medium and fine pores were correlated with soil clay content(r=0.381 and 0.687,respectively,P<0.001).In addition,the PSI of fine pores was also correlated with montmorillonite content(r=0.387,P<0.01).It can be concluded that the PSI of large pores is related to anthropogenically influenced soil properties with low stability,whereas those of medium and fine pores are related to pedogenic *** high variability in anthropogenic and pedogenic factors explains the spatial pattern of Vertisol shrinkage capacity on the North China Plain.

关键词： clay content coefficient of linear extensibility pore shrinkage index soil structure spatial distribution swelling

Evolution of tribo-magnetization during sliding of ferromagnetic materials

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Friction 2024年第5期12卷 906-918页

作者： Fumin GAO Laibin ZHANG Jin ZHOU Yi xiong jing WU Jianchun FAN China University of Petroleum-Beijing Beijing102249China Key Laboratory of Oil and Gas Safety and Emergency Technology Ministry of Emergency ManagementBeijing102249China

Sliding-induced subsurface microstructure evolution is believed to be decisive for determining the friction and wear performance of metallic contacts as well as the development of *** expects to develop a new prediction method of wear state by elucidating the correlation between subsurface microstructure evolution and corresponding magnetic domain ***,subsurface microstructure evolution including crystal and magnetic domain under tribological action is investigated *** results demonstrate that dislocation mediated plastic deformation decisively influences microstructural changes during tribological contact,further determining the magnetic domain ***,sliding-induced plastic deformation causes an increase in the width of magnetic domains,but depth-dependent derived microstructure formed under severe plastic deformation such as the refined grains and sub-grains,in turn,promoted the refinement of magnetic domains and their discontinuity,forming depth-dependent magnetic domain *** results are helpful to clarify the evolution of tribo-magnetization and the pinning effect of dislocations on magnetic domains.

关键词： tribology magnetic domain microstructure tribo-magnetization dislocations