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Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He Si-yuan Feng Jian Zhang Hong-wu Tang Yang Xiao sheng Chen Chun-sheng Liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM

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Sex-biased adaptation shapes uniparental gene pools in Tibetans

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Science China(Life Sciences) 2024年第3期67卷 611-613页

作者： Min-sheng Peng Ya-Ping Zhang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming 650201China KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases Kunming Institute of ZoologyChinese Academy of SciencesKunming 650201China Kunming College of Life Science University of Chinese Academy of SciencesKunming 650204China State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan School of Life SciencesYunnan UniversityKunming 650091China

During the past two decades, a series of archaeological and genetic investigations substantially improve our perception of the hominin settlement of the Tibetan Plateau(Zhang et al., 2022). In addition to the identifi... 详细信息

关键词： Tibetan Plateau altitude

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Landsat Image-Based Spatiotemporal Variation Analysis of Erosion and Deposition off the Qingshuigou of the Yellow River Delta from 1984 to 2021

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Journal of Ocean University of China 2024年第5期23卷 1173-1184页

作者： DONG sheng LI Songda TAO Shanshan College of Engineering Ocean University of ChinaQingdao 266404China

Owing to climate change and human activity,the Qingshuigou of the Yellow River Delta(YRD)has undergone dynamic changes in erosion and ***,studying these changes is important to ensure ecological protection and sustainable *** this study,the trend of erosion-deposition evolution in the Qingshuigou was investigated based on 38 coastline phases extracted from Landsat series images of the YRD at one-year intervals from 1984 to *** periodicity of the scouring and deposition evolution was also analyzed using wavelet *** showed that the total area of the Qingshuigou was affected by deposition and erosion and that the fluctuation first increased and then *** total area reached a maximum in *** depositional area first increased and then decreased,whereas the overall erosion area *** and erosion areas showed periodic changes to some extent;however,the periodic signal intensity ***,factors including channel morphological evolution and variations in water and sediment discharge affect the spatiotemporal dynamics of erosion and deposition *** application of nonconsistency tests finally revealed that deposition area and flushing magnitude exhibited non-stationarities,which are potentially attributed to impacts from climatic change drivers.

关键词： Yellow River Delta coastline erosion and deposition remote sensing wavelet analysis

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从“东西对立”到“内外有别”:西汉国家政治地理结构演变——以《二年律令·秩律》《汉书·地理志》郡级政区排序为视角

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社会科学 2024年第1期 52-68页

作者：马孟龙复旦大学历史学系

张家山汉简《二年律令·秩律》政区排序显示,汉朝存在以内史为核心,自西向东排列“关中郡”“关外郡”两个政治地理层级。这种政治地理结构乃针对关东诸侯王国而建设,呈“东西对立”态势。汉武帝元封年间,汉朝政治地理结构发生重大转变... 详细信息

张家山汉简《二年律令·秩律》政区排序显示,汉朝存在以内史为核心,自西向东排列“关中郡”“关外郡”两个政治地理层级。这种政治地理结构乃针对关东诸侯王国而建设,呈“东西对立”态势。汉武帝元封年间,汉朝政治地理结构发生重大转变,汉郡分化为边郡、内郡。内郡中的弘农郡、“三河”地位抬升,带有“准京畿”的特征。由此汉朝国家政治地理结构形成以三辅、弘农郡、“三河”为核心,外围环绕内郡,再环绕边郡的圈层政治地理结构。诸侯王国被纳入汉朝国家政治地理结构后,政治地位与内郡相似。《汉书·地理志》郡级政区排序虽然呈现“京畿—内郡—边郡”政治地理结构,却将王国排列于边郡之后,同时强调“关中郡”的特殊地位,与西汉末年国家政治地理构造实况存在一定差异。这体现出汉初“以关中制关外”“封藩屏蔽”的政治理念对政治地理观念的塑造,仍发挥作用。

关键词：政治地理国家政治地理结构《二年律令·秩律》《汉书·地理志》郡级政区排序

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A Microstrip Leaky-Wave Antenna with Scanning Beams Horizontal to the Antenna Plane

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Chinese Journal of Electronics 2024年第5期33卷 1218-1223页

作者： Henghui WANG Peiyao CHEN sheng SUN School of Electronic Science and Engineering University of Electronic Science and Technology of China

A leaky-wave antenna with horizontal scanning beams and broadside radiation is presented on the periodically modulated microstrip. The horizontal radiation is realized by periodically etching a set of resonant open-ended slots on the ground plane. Dispersion diagrams and Bloch impedance are first analyzed to investigate the propagation and radiation characteristics of the periodic structure. Subsequently, shunt matching stubs are installed aiming to obtain seamless beam scanning property through the broadside. Finally, a prototype is implemented as verification of the presented antenna. Results of the simulations and measurements agree well with each other, indicating the elimination of the open-stop band effect and the horizontal radiation beams. The fabricated antenna exhibits a beam range from -62° to +34°, and provides a maximum measured gain about 14.6 dBi at 10 GHz.

关键词： Antenna measurements Wireless communication Prototypes Microstrip antennas Gain measurement Leaky wave antennas Reflection coefficient Bloch impedance Horizontal radiation Leaky-wave antenna Microstrip line Seamless beam scanning ASYMMETRY

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Navigating Epstein–Barr virus autoimmunity:role of NK cells and T cells in multiple sclerosis

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Signal Transduction and Targeted Therapy 2024年第3期9卷 833-835页

作者： Chu Xie Cong Sun Mu-sheng Zeng State Key Laboratory of Oncology in South China Guangdong Provincial Clinical Research Center for CancerGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapySun Yat-sen University Cancer CenterGuangzhouP.R.China

In a recent study published in Cell,Vietzen and colleagues discovered the novel role of natural killer(NK)cells and EBVspecific CD8+T cell response in controlling EBV-inducing autoimmune response and collectively def... 详细信息

关键词： Epstein sclerosis killer

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New formula for predicting the plastic buckling pressure of steel torispherical heads under internal pressure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 618-630页

作者： sheng YE Keming LI Jinyang ZHENG Shan SUN Institute of Process Equipment Zhejiang UniversityHangzhou 310027China Engineering Research Center for High Pressure Process Equipment and Safety of Ministry of Education Hangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Hangzhou 310058China

Thin-walled torispherical heads under internal pressure can fail by plastic buckling because of compressive circumferential stresses in the head ***,existing formulas still have limitations,such as complicated expressions and low accuracy,in determining buckling *** this paper,we propose a new formula for calculating the buckling pressure of torispherical heads based on elastic-plastic analysis and experimental ***,a finite element(FE)method based on the arc-length method is established to calculate the plastic buckling pressure of torispherical heads,considering the effects of material strain hardening and geometrical *** buckling pressure results calculated by the FE method in this paper have good consistency with those of BOSOR5,which is a program for calculating the elastic-plastic bifurcation buckling pressure based on the finite difference energy ***,the effects of geometric parameters,material parameters,and restraint form of head edge on buckling pressure are ***,a new formula for calculating plastic buckling pressure is developed by fitting the curve of FE results and introducing a reduction factor determined from experimental ***,based on the experimental results,we compare the predictions of the new formula with those of existing *** is shown that the new formula has a higher accuracy than the existing ones.

关键词： Torispherical head Plastic buckling Elastic-plastic analysis Prediction formula Finite element method

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A Deep Model for Partial Multi-label Image Classification with Curriculum-based Disambiguation

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Machine Intelligence Research 2024年第4期21卷 801-814页

作者： Feng Sun Ming-Kun Xie sheng-Jun Huang MIIT Key Laboratory of Pattern Analysis and Machine Intelligence College of Computer Science and TechnologyNanjing University of AeronauticsandAstronauticsNanjing211106China

In this paper,we study the partial multi-label(PML)image classification problem,where each image is annotated with a candidate label set consisting of multiple relevant labels and other noisy *** PML methods typically design a disambiguation strategy to filter out noisy labels by utilizing prior knowledge with extra assumptions,which unfortunately is unavailable in many real ***,because the objective function for disambiguation is usually elaborately designed on the whole training set,it can hardly be optimized in a deep model with stochastic gradient descent(SGD)on *** this paper,for the first time,we propose a deep model for PML to enhance the representation and discrimination *** the one hand,we propose a novel curriculum-based disambiguation strategy to progressively identify ground-truth labels by incorporating the varied difficulties of different *** the other hand,consistency regularization is introduced for model training to balance fitting identified easy labels and exploiting potential relevant *** experimental results on the commonly used benchmark datasets show that the proposed method significantlyoutperforms the SOTA methods.

关键词： Partial multi-label image classification curriculum-based disambiguation consistency regularization label difficulty candidatelabel set.

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Adaptive Observer-Based Finite-Time Fault Tolerant Control for Non-Strict Feedback Systems

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Journal of Systems Science & Complexity 2024年第4期37卷 1526-1544页

作者： sheng Ning LIU Yang CHI Ronghu AI Zidong College of Automation and Electronic Engineering Qingdao University of Science and TechnologyQingdao 266042China

This paper considers the adaptive finite-time control and observer design method for a class of non-strict feedback systems with unmeasurable states,unknown nonlinear dynamics and actuator *** this paper,an observer is proposed to estimate the unmeasurable states in finite-time based on adaptive technique and neural networks,while the actuator faults are not *** filter is used to solve the computational explosion and singularity problems caused by the traditional backstepping and non-strict feedback structure,*** the fault efficiency indicators in real systems are not available,two-layer neural networks are adopted,where the first network is to estimate the unknown nonlinearities of systems and the second one is to estimate fault efficiency indicators and unknown nonlinear *** proposed scheme guarantees that states are bounded through stability ***,two experiments including a numerical example and a spring-mass-damper system are given to verify the effectiveness of the proposed method.

关键词： Command filter fault tolerant control finite-time control non-strict systems two-layer neural networks

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Recent Advances in Deciphering the Mechanisms and Biological Functions of DNA Demethylation

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Chinese Journal of Chemistry 2024年第6期42卷 645-651页

作者： Yang Feng sheng-Jun Chen Bi-Feng Yuan Key Laboratory of Aquatic Product Processing Ministry of Agriculture and Rural AffairsNational R&D Center for Aquatic Product ProcessingSouth China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhouGuangdong510300 China School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhanHubei430071 China

5-Methylcytosine (5mC) is a dynamic and reversible epigenetic modification in genomic DNA of higher *** has been well-established that the demethylation of 5mC occurs through the ten-eleven translocation (TET)-mediated oxidation of 5mC followed by thymine DNA glycosylase (TDG)-initiated base excision repair (BER).Recent findings also have identified an alternative pathway of DNA *** this pathway,TET enzymes directly oxidize 5mC to form 5-formylcytosine (5fC) or 5-carboxylcytosine (5caC).These modified bases can undergo direct deformylation or decarboxylation,***,DNA demethylation can also occur through the deamination of 5mC and 5hmC,resulting in the production of thymine and 5-hydroxymethyluracil (5hmU),*** DNA demethylation pathways possess critical functional implications and roles in biological *** Recent Advances article will focus on the studies of mechanisms and biological functions of DNA demethylation,shedding light on the reversible nature of the epigenetic modification of 5mC.

关键词： Epigenetics DNA DNA methylation 5-Methylcytosine Demethylation Mechanisms Biological functions C—C bond cleavage Mass spectrometry

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