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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 126-130页

作者： WU Ya-hui,GUO Jun,LIU Gang laboratory of pattern recognition and intelligent system,Beijing University of Posts and Telecommunications,Beijing 100876,China laboratory of pattern recognition and intelligent system Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a model combination method to enhance the discriminability of the generative model. Generative and discriminative models have different optimization objectives and have their own advantages and drawbacks. The method proposed in this article intends to strike a balance between the two models mentioned above. It extracts the discriminative parameter from the generative model and generates a new model based on a multi-model combination. The weight for combining is determined by the ratio of the inter-variance to the intra-variance of the classes. The higher the ratio is, the greater the weight is, and the more discriminative the model will be. Experiments on speech recognition demonstrate that the performance of the new model outperforms the model trained with the traditional generative method.

关键词： model combination discriminability generative model training speech recognition

Spatiotemporal variation of rainy season span and precipitation recorded by lacustrine laminated pollen in the Tibetan Plateau during the past two millennia

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Science China Earth Sciences 2024年第3期67卷 789-801页

作者： Anning CUI Houyuan lu Juzhi HOU Xingqi LIU Deke XU Key laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Group of Alpine Paleoecology and Human Adaptation State Key Laboratory of Tibetan Plateau Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Capital Normal University College of Resource Environment and Tourism Beijing 100048China

The quantitative reconstruction of the length of the rainy season and precipitation on the Tibetan Plateau(TP) is crucial for revealing the spatiotemporal evolution of the Westerlies and Asian summer monsoon, as well as its ecological and environmental effects. Accurately determining the start and end times of the rainy season on the Plateau remains *** study determined the start and end times of the rainy season in different locations on the Plateau by identifying precipitation inflection points. We calculated the duration and precipitation amount of the rainy season and established a transfer function between the modern pollen assemblages and them. Then, we reconstructed the rainy season variations in Kusai Lake(northern TP) and Jiang Co(central TP) during the past two millennia. The results showed that, the rainy season precipitation in Kusai Lake recorded five periods of high precipitation: AD 580–680, 1000–1100, 1200–1450, 1550–1780, and 1920–present, corresponding to the stages with long rainy season. The rainy season precipitation sequence in Jiang Co recorded four periods of high precipitation: AD 80–500, 800–950, 1250–1450, and 1780–present, which is consistent with the long rainy season before AD 1000 but unclear afterward. Spatially, rainy season precipitation on the Plateau exhibited four patterns: “wet in both north and south” may be related to abnormally strong summer monsoons;“dry in both north and south” likely associated with weak Westerly wind and weak summer monsoon;“wet in the south and dry in the north” linked to strong summer monsoon and weak Westerly wind;and “dry in the south and wet in the north” connected to weak summer monsoon and strong Westerly wind. This study revealed the spatiotemporal evolution pattern of the rainy season onset and end, duration, and precipitation amount on the Plateau over the past two millennia. It provides natural background support for further understanding the coupling between Westerly wind and Asia

关键词： Tibetan Plateau Past two millennia Rainy season length Rainy season precipitation Quantitative reconstruction

Fast spreading of surface ozone in both temporal and spatial scale in Pearl River Delta

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Journal of Environmental Sciences 2024年第3期137卷 540-552页

作者： Tianhui Cao Haichao Wang Lei Li Xiao lu Yiming Liu Shaojia Fan School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationZhuhai 519082China

Surface ozone(O_(3))is a major air pollutant and draw increasing attention in the Pearl River Delta(PRD),***,we characterize the spatial-temporal variability of ozone based on a dataset obtained from 57 national monitoring sites during *** results show that:(1)the seasonal difference of ozone distribution in the inland and coastal areas was significant,which was largely affected by the wind pattern reversals related to the East Asian monsoon,and local ozone production and destruction;(2)the daily maximum 8hr average(MDA8 O_(3))showed an overall upward trend by 1.11 ppbv/*** the trends in the nine cities varied differently by ranging from-0.12 to 2.51 ppbv/*** hot spots of ozone were spreading to southwestern areas from the central areas since *** ozone is becoming a year-round air pollution problem with the pollution season extending to winter and spring in PRD region.(3)at the central and southwestern PRD cities,the percentage of exceedance days from the continuous type(defined as≥3 days)was ***,the ozone concentration of continuous type was much higher than that of scattered exceedance type(lution days and highlight the great challenge in mitigation of O_(3)pollution in these cities.

关键词： Surface ozone pollution Ozone trend Spatial and temporal variability Pearl River Delta Pollution mitigation

A comparison of statistical learning of naturalistic textures between DCNNs and the human visual hierarchy

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Science China Technological Sciences 2024年第8期67卷 2310-2318页

作者： lu XinCheng YUAN ZiQi ZHANG YiChi AI HaiLin CHENG SiYuan GE YiRan FANG Fang CHEN NiHong Department of Psychological and Cognitive Sciences Tsinghua University Department of Computer Science and Technology Tsinghua University School of Psychological and Cognitive Sciences and Beijing Key laboratory of Behavior and Mental Health Peking University Key laboratory of Machine Perception (Ministry of Education) Peking University Peking-Tsinghua Center for Life Sciences Peking University IDG/McGovern Institute for Brain Research Peking University State Key laboratory of Brain and Cognitive Science Institute of Psychology Chinese Academy of Sciences IDG/McGovern Institute for Brain Research Tsinghua University

The visual system continuously adapts to the statistical properties of the environment. Existing evidence shows a close resemblance between deep convolutional neural networks(CNNs) and primate visual stream in neural selectivity to naturalistic textures above the primary visual processing stage. This study delves into the mechanisms of perceptual learning in CNNs,focusing on how they assimilate the high-order statistics of natural textures. Our results show that a CNN model achieves a similar performance improvement as humans, as manifested in the learning pattern across different types of high-order image statistics. While L2 was the first stage exhibiting texture selectivity, we found that stages beyond L2 were critically involved in learning. The significant contribution of L4 to learning was manifested both in the modulations of texture-selective responses and in the consequences of training with frozen connection weights. Our findings highlight learning-dependent plasticity in the mid-to-high-level areas of the visual hierarchy. This research introduces an AI-inspired approach for studying learning-induced cortical plasticity, utilizing DCNNs as an experimental framework to formulate testable predictions for empirical brain studies.

关键词： CNN perceptual learning naturalistic texture psychophysics

Global Dynamic Responses and Progressive Failure of Submerged Floating Tunnel Under Cable Breakage Conditions

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China Ocean Engineering 2024年第4期38卷 676-688页

作者： ZHOU Xiang-bo QIAO Dong-sheng WANG Ming TANG Guo-qiang lu Lin OU Jinping State Key laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The Submerged Floating Tunnel(SFT)relies on a tensioned mooring system for precise *** sudden breakage of a single cable can trigger an immediate alteration in the constraint conditions of the tube,inducing a transient heave response within the structure along with a transient increase in cable tension experienced by adjacent *** more severe cases,this may even lead to a progressive failure culminating in the global destruction of the *** study used ANSYS/AQWA to establish a numerical model of the entire length SFT for the hydrodynamic response analysis,and conducted a coupled calculation of the dynamic responses of the SFT-mooring line model based on Orca Flex to study the global dynamic responses of the SFT at the moment of cable breakage and the redistribution of cable internal *** most unfavorable position for SFT cable breakage was identified,the influence mechanism of cable breakage at different positions on the global dynamic response was revealed,and the progressive chain failure pattern caused by localized cable breakage are also clarified.

关键词： submerged floating tunnel cable breakage global dynamic responses progressive failure

Approximate computation of Madaline sensitivity based on discrete stochastic technique

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Science China(Information Sciences) 2010年第12期53卷 2399-2414页

作者： ZHONG ShuiMing , ZENG XiaoQin, LIU HuiYi & XU Yan Institute of pattern recognition and intelligent system, College of Computer and Information Engineering, Hohai University, Nanjing 210098, China Institute of pattern recognition and intelligent system College of Computer and Information Engineering Hohai University Nanjing China

The computation of the sensitivity of a Madaline’s output to its parameter perturbation is system- atically discussed. Firstly, according to the discrete feature of Adalines, a method based on discrete stochastic technique is proposed, which derives some analytical formulas for the computation of Adalines’ sensitivity. The method can theoretically solve some problems that are unsolvable by the existing methods based on continu- ous stochastic techniques, release some unpractical constraints, and make it available to theoretically analyze the approximation error of Adalines’ sensitivity. Secondly, on the basis of the sensitivity of Adalines and the structural characteristics of Madalines, a new selection strategy depending on a type of dedication degree for computing Madalines’ sensitivity is proposed, which is superior to current popular way of simply averaging in both precision and complexity. The proposed formulas and algorithm have the advantages of simplicity, low computational complexity, small approximation error, and high generality, as have been verified by a great amount of experimental simulations.

关键词： Adaline Madaline feedforward networks sensitivity parameter perturbation stochastic discrete technique

CsABF3-activated CsSUT1 pathway is implicated in pre-harvest water deficit inducing sucrose accumulation in citrus fruit

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Horticultural Plant Journal 2024年第1期10卷 103-114页

作者： Xiaochuan Ma Yuanyuan Chang Feifei Li Junfeng Yang Li Ye Tie Zhou Yan Jin Ling Sheng Xiaopeng lu College of Horticulture Hunan Agricultural UniversityChangshaHunan 410128China National Center for Citrus Improvement ChangshaHunan 410128China Institute of Horticulture Hunan Academy of Agricultural ScienceChangshaHunan 410125China

Pre-harvest water deficit(PHWD)plays an important role in sugar accumulation of citrus ***,the mechanism is not known ***,it was confirmed that PHWD promoted sucrose accumulation of citrus fruit,but had limited effect on fructose,glucose and total acid.A sucrose transporter,Cs SUT1,which localizes to the plasma membrane,was demonstrated to function in sucrose transport induced by *** to wild-type,Cs SUT1 overexpression in citrus calli stimulated sucrose,fructose and glucose accumulation,while its silencing in juice sacs reduced sucrose *** sugar accumulation in transgenic lines enhanced plant drought tolerance,and resulted in decreased electrolyte leakage,malondialdehyde and hydrogen peroxide contents,as well as increased superoxide dismutase activity and proline *** abscisic acid(ABA)-responsive transcription factor,Cs ABF3,was found with a same expression pattern with Cs SUT1 under *** one-hybrid,electrophoretic mobility shift assay and dual-luciferase assays all revealed that Cs ABF3 directly bound with the Cs SUT1 promoter by ABA responsive *** Cs ABF3 was overexpressed in citrus calli,the sucrose,fructose and glucose concentration increased ***,transgenic studies demonstrated that Cs ABF3 could affect sucrose accumulation by regulating Cs ***,this study revealed a regulation of Cs ABF3 promoting Cs SUT1 expression and sucrose accumulation in response to *** results provide a detail insight into the quality formation of citrus fruit.

关键词： Citrus Water deficit Pre-harvest Sucrose CsABF3 CsSUT1

Automatic real-time SLAM relocalization based on a hierarchical bipartite graph model

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Science China(Information Sciences) 2012年第12期55卷 2841-2848页

作者： DONG QiuLei ,GU ZhaoPeng & HU ZhanYi National laboratory of pattern recognition(NLPR),Institute of Automation,Chinese Academy of Sciences,Beijing 100190,China National laboratory of pattern recognition (NLPR) Institute of Automation Chinese Academy of Sciences Beijing China

The need to increase the robustness of a real-time monocular SLAM system raises the important problem of relocalization;namely,how to automatically recover a SLAM system after tracking *** address this problem by proposing a real-time relocalization algorithm based on a hierarchical bipartite graph *** the SLAM system is lost,we use the latter model to find sufficient correspondences between the detected image and stored map features,thus achieving efficient,real-time *** model accounts for both temporal and spatial *** results on both synthetic and real data support the effectiveness of the proposed algorithm.

关键词： monocular SLAM real-time relocalization hierarchical bipartite graph model

Advanced hepatocellular carcinoma in a patient with neurofibromatosis type 1 and malignant peripheral nerve sheath tumor

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 530-532页

作者： Ahmad Alhaskawi Yan-Zhao Dong Xiao-Di Zou Sohaib Hasan Abdullah Ezzi Ze-Wei Wang Hai-Ying Zhou Sahar Ahmed Abdalbary Hui lu Department of Orthopedics the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Chinese Medicine the Second Affiliated HospitalZhejiang Chinese Medical UniversityHangzhou 310005China Department of Orthopedics the Third Xiangya HospitalCentral South UniversityChangsha 410083China Zhejiang University School of Medicine Hangzhou 310000China Department of Orthopedic Physical Therapy Faculty of Physical TherapyNahda University in Beni SuefBeni SuefEgypt

To the Editor: Neurofibromatosis type 1(NF-1), or Von Recklinghausen disease, is a genetic disorder inherited in an autosomal dominant pattern. It is caused by a mutation in the neurofibromin gene located on chromosome 17, accounting for 96% of all neurofibromatosis cases. This condition can affect multiple systems and often leads to the formation of tumors along the nervous system [1]. Patients with NF-1 may exhibit various symptoms, including Lisch nodules, neurofibromas, scoliosis, café au lait spots, learning disabilities, vision disorders, and epilepsy.

关键词： epilepsy hepatocellular malignant