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Integral precession calibration method of PIGA on linear vibration table

Chinese Journal of Aeronautics 2024年第3期37卷 219-236页

作者： Chuang SUN Shun-qing REN jun-wei CAO Ru huo Department of Automation Tsinghua UniversityBeijing 100084China School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Faculty of Information technology Beijing University of TechnologyBeijing 100124China

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this *** on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is *** angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are *** complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration *** effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test *** and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related *** order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,*** with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method.

关键词： PIGA Linear vibration table Vibration measurement Calibration Error analysis Uncertainty analysis

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Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1661-1667页

作者： Gu-jun Chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

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Two New Cytotoxic Sesquiterpenoids from Eupatorium lindleyanum DC.

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Journal of Integrative Plant Biology 2006年第4期48卷 473-477页

作者： jun huo sheng-Ping Yang Jian Ding Jian-Min Yue State Key Laboratory of Drug Research Institute of Materia Medica Shanghai Institute for Biological Sciences the Chinese Academy of Sciences Shanghai 201203 China

Two new sesqulterpenold lactones, namely eupallnllides K and L, were isolated from Eupatorlum Ilndleyanum DC. Their structures were determined by spectral methods, Including 1 D-and 2D-NMR spectra. Cytotoxlc evaluatlon showed that eupallnlllde L exhibited potent cytotoxlclty against P-388 and A-549 tumor cell lines with IC50 values of 0.17 and 2.60 p, mol/L, respectively.

关键词： eupalinilides K and L Eupatorium lindleyanum sesquiterpenoid

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Cohomology groups of a new class of Kadison-Singer algebras

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Science China Mathematics 2024年第3期67卷 593-606页

作者： Guangyu An Xing Cheng jun sheng School of Mathematics and Data Science Shaanxi University of Science and TechnologyXi’an 710021China

Let N be a maximal discrete nest on an infinite-dimensional separable Hilbert space H,ξ=∑^(∞)_(n=1)en/2n be a separating vector for the commutant N',E_(ξ)be the projection from H onto the subspace[Cξ]spanned by the vectorξ,and Q be the projection from K=H⊕H⊕H onto the closed subspace{(η,η,η)^(T):η∈H}.Suppose that L is the projection lattice generated by the projections(E_(ξ) 0 0 0 0 0 0 0 0),{(E 0 0 0 0 0 0 0 0):E∈N},(I 0 0 0 I 0 0 0 0) and *** show that L is a Kadison-Singer lattice with the trivial ***,we prove that every n-th bounded cohomology group H~n(AlgL,B(K))with coefficients in B(K)is trivial for n≥1.

关键词： Kadison-Singer algebra Kadison-Singer lattice derivation cohomology group

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Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research(International) 2024年第4期31卷 828-837页

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

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Numerical Study on the Effect of Gap Diffraction on the Hydrodynamic Performance of A Floating Breakwater

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China Ocean Engineering 2024年第4期38卷 663-675页

作者： BIAN Xiang-qian JI Chun-yan XU sheng GUO Jian-ting huo Fa-li School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Two-dimensional(2D)flume experiments are useful in investigating the performances of floating breakwaters(FBs),including hydrodynamic performances,motion responses,and mooring *** a reasonable gap between the flume wall and the FBs is a critical step in 2D flume ***,research on the effect of the gap on the accuracy of 2D FB experimental results is *** address this issue,a numerical wave tank is developed using CFD to estimate the wave-FB interaction of a moored dual-cylindrical FB,and the results are compared to experimental data from a previously published *** is good agreement between them,indicating that the numerical model is sufficiently *** numerical model is then applied to explore the effect of gap diffraction on the performance of FBs in2D *** was discovered that the nondimensional gap length L_(Gap)/W_(Pool)should be smaller than 7.5%to ensure that the relative error of the transmission coefficient is smaller than 3%.The influence of the gap is also related to the entering wave properties,such as the wave height and period.

关键词： floating breakwater diffraction effect gap hydrodynamic performance model experiments CFD numerical simulation

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Establishment of an Iron Deficiency Model by Iron Depletion in Pregnant Rats

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Biomedical and Environmental Sciences 2024年第2期37卷 210-215页

作者： CHEN Xi HAN Chao ZHAO Jin Peng SHEN Shi WANG Li Yuan REN Shou WANG Tong Lei MA Yan XU Ze Chao huo jun sheng Key Laboratory of Trace Element Nutrition National Health Commission of the People’s Republic of ChinaNational Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China

Anemia,a global public health problem,has significant adverse consequences on the cognitive development of children and the work capacity of adults;affecting social and economic ***,roughly 43%of children under five years of age,38%of pregnant women,and 29%of nonpregnant women had *** during pregnancy significantly increases the risk of low birth weight and preterm birth.A 10 g/L increase in hemoglobin has been estimated to decrease the risk of maternal and perinatal mortality by 29%and 28%.

关键词： mortality pregnancy anemia

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Optical colorimetric LiTaO_(3)wafers for highprecision lithography on frequency control of SAW devices

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Photonics Research 2024年第2期12卷 341-349页

作者： MING HUI FANG YINONG XIE FANGQI XUE ZHILIN WU jun SHI sheng YU YANG YILIN LIU ZHIHUANG LIU HSIN CHI WANG FAjun LI QING huo LIU JINFENG ZHU School of Electronic Science and Engineering Xiamen UniversityXiamen 361005China Quanzhou San’an Integrated Circuit Co. Ltd.Quanzhou 362300China Eastern Institute of Technology Ningbo 315200China

Surface acoustic wave(SAW)resonators based on lithium tantalate(LT,LiTaO_(3))wafers are crucial elements of mobile communication *** use of intrinsic LT wafers typically brings about low fabrication accuracy of SAW resonators due to strong UV reflection in the lithography *** hinders their resonance frequency control seriously in industrial *** doping and chemical reduction could be applied to decrease the UV reflection of LT wafers for high lithographic ***,conventional methods fail to provide a fast and nondestructive approach to identify the UV performance of standard single-side polished LT wafers for highprecision frequency ***,we propose a convenient on-line sensing scheme based on the colorimetry of reduced Fe-doped LT wafers and build up an automatic testing system for industrial *** levels of Fe doping and chemical reduction are evaluated by the lightness and color difference of LT-based *** correlation between the wafer visible colorimetry and UV reflection is established to refine the lithography process and specifically manipulate the frequency performance of SAW *** study provides a powerful tool for the fabrication control of SAW resonators and will inspire more applications on sophisticated devices of mobile communication.

关键词： lithography doping wafer

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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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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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