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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 289-310页

作者： Zhendong luo fei TENG School of Mathematics and Physics North China Electric Power University Beijing 102206 China School of Control and Computer Engineering North China Electric Power University Beijing 102206 China

This paper is concerned with establishing a reduced-order extrapolating fi- nite volume element （FVE） format based on proper orthogonal decomposition （POD） for two-dimensional （2D） hyperbolic equations. For this purpose, a semi discrete variational format relative time and a fully discrete FVE format for the 2D hyperbolic equations are built, and a set of snapshots from the very few FVE solutions are extracted on the first very short time interval. Then, the POD basis from the snapshots is formulated, and the reduced-order POD extrapolating FVE format containing very few degrees of freedom but holding sufficiently high accuracy is built. Next, the error estimates of the reduced-order solutions and the algorithm procedure for solving the reduced-order for- mat are furnished. Finally, a numerical example is shown to confirm the correctness of theoretical conclusions. This means that the format is efficient and feasible to solve the 2D hyperbolic equations.

关键词： reduced-order finite volume element (FVE) extrapolating format properorthogonal decomposition (POD) hyperbolic equation error estimate numerical simula-tion

Self-supervised coarse-to-fine monocular depth estimation using a lightweight attention module

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Computational Visual Media 2022年第4期8卷 631-647页

作者： Yuanzhen Li fei luo Chunxia Xiao School of Computer Science Wuhan UniversityWuhan 430072China

Self-supervised monocular depth estimation has been widely investigated and applied in previous ***,existing methods suffer from texture-copy,depth drift,and incomplete *** is difficult for normal CNN networks to completely understand the relationship between the object and its surrounding ***,it is hard to design the depth smoothness loss to balance depth smoothness and *** address these issues,we propose a coarse-to-fine method with a normalized convolutional block attention module(NCBAM).In the coarse estimation stage,we incorporate the NCBAM into depth and pose networks to overcome the texture-copy and depth drift ***,we use a new network to refine the coarse depth guided by the color image and produce a structure-preserving depth result in the refinement *** method can produce results competitive with state-of-the-art *** experiments prove the effectiveness of our two-stage method using the NCBAM.

关键词： monocular depth estimation texture copy depth drift attention module

Lead-Lag Connection of the Atlantic Multidecadal Oscillation (AMO) with East Asian Surface Air Temperatures in Instrumental Records

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Atmospheric and Oceanic Science Letters 2013年第3期6卷 138-143页

作者： LI Shuanglin luo fei-fei Climate Change Research Center and Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The authors analyzed the lead-lag connection of the Atlantic Multidecadal Oscillation (AMO) with East Asian surface air temperatures (EATs) using instrumental records, and compared the results with the Pacific Decadal Oscillation (PDO). The maximum correlation was found when EATs led the AMO by five to seven years (with a correlation coefficient of 0.72, whereas the correlation coefficient was 0.91 when the AMO led EATs by 24-28 years). This is different from the PDO, which mostly correlated with EATs when the PDO led EATs by 13-15 years (with a correlation coefficient of 0.67, whereas the correlation coefficient was 0.76 when EATs led the PDO by 24-26 years). The PDO led the AMO by 19-21 years (with a correlation coefficient of 0.71, whereas the correlation coefficient was 0.84 when the AMO led the PDO by 16-18 years). These results support a previous understanding that EATs positively correlate with the AMO, and imply that the observed East Asian warming trend may have been slowing down since the early 2010s.

关键词： EATs AMO PDO instrumental records

Weaker connection between the Atlantic Multidecadal Oscillation and Indian summer rainfall since the mid-1990s

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Atmospheric and Oceanic Science Letters 2018年第1期11卷 37-43页

作者： luo fei-fei LI Shuanglin Tore FUREVIK Nansen-Zhu International Research Centre and Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science China University of Geosciences Wuhan China Geophysical Institute and Bjerknes Centre for Climate Research University of Bergen Bergen Norway

Previous studies have shown that the Atlantic Multidecadal Oscillation （AMO） can play an important role in modulating the variabilityoflndian summer monsoon rainfall （ISMR） over a 50-60-yr timescale. A significant positive correlation between the AMO and ISMR is found both in observations and models. However, instrumental records show that the relationship becomes non-significant or even of opposite sign after the mid-1990s, suggesting a weakening of the AMO-ISMR connection. The mechanism for the breakdown of the AMO-ISMR connection is investigated in the present work, and the results suggest that a substantial warming in the Indian-tropical western Pacific Ocean plays a role. The warming weakens the meridional gradient of tropospheric temperature between Eurasia and the indian Ocean, and reduces the meridional sea level pressure gradient between the Indian Subcontinent and Indian Ocean, weakening the Indian summer monsoon. Thus, warming in the Indian-tropical western Pacific Ocean seems responsible for the weakened connection between the AMO and ISM.

关键词： Atlantic MultidecadalOscillation Indian summerrainfall connection multidecadal variation

A micro–macro constitutive model for rock considering breakage effects

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International Journal of Mining Science and Technology 2023年第2期33卷 173-184页

作者： Di Yu Enlong Liu Bo Xiang Yunyong He fei luo Chuan He State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China b Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu 610207China Highway Planning Survey and Design Research InstituteSichuan Provincial Transport DepartmentChengdu 610041China College of Civil Engineering Sichuan Agricultural UniversityChengdu 611830China

The paper proposes a three-scale binary medium-based constitutive model on the basis of the meso structures and micro components to describe the elasto-plastic mechanical behavior of mudstone *** on the breakage mechanism of geomaterials,mudstone samples are considered as two different materials(bonded and frictional elements)at *** micro to meso scales,given the similar but different mineralogy composition and porosity of the bonded and frictional elements at microscale,as well as their separate mechanical characteristics,different homogenization methods are adopted to obtain their respective meso mechanical *** the mesoscale,in view of the unique meso structures and the continuous material transformation,the extended self-consistent scheme(SCS)is improved to be adaptable to elasto-plastic composites with varying meso *** the consideration of the evolution form of the breakage ratio under the external loading being given based on the assumed strength distribution of the meso bonded elements,the mechanical relations between meso and macro scales are ***,on the basis of the mean-field method and combined with the critical mechanical connections between different scales,the micro-meso-macro constitutive model for mudstone samples are *** model validation shows that,with a few model parameters,the proposed model can well reflect the stress and deformation features of mudstone samples with complex micro-components.

关键词： Micromechanics Binary-medium model Multiscale model Breakage mechanism Mudstone

A Comprehensive Pipeline for Complex Text-to-Image Synthesis

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Journal of Computer Science & Technology 2020年第3期35卷 522-537页

作者： fei Fang fei luo Hong-Pan Zhang Hua-Jian Zhou Alix L.H.Chow Chun-Xia Xiao School of Computer Science Wuhan UniversityWuhan 430072China Xiaomi Technology Co.LTD Beijing 100085China

Synthesizing a complex scene image with multiple objects and background according to text description is a challenging *** needs to solve several difficult tasks across the fields of natural language processing and computer *** model it as a combination of semantic entity recognition,object retrieval and recombination,and objects’status *** reach a satisfactory result,we propose a comprehensive pipeline to convert the input text to its visual *** pipeline includes text processing,foreground objects and background scene retrieval,image synthesis using constrained MCMC,and ***,we roughly divide the objects parsed from the input text into foreground objects and background ***,we retrieve the required foreground objects from the foreground object dataset segmented from Microsoft COCO dataset,and retrieve an appropriate background scene image from the background image dataset extracted from the ***,in order to ensure the rationality of foreground objects’positions and sizes in the image synthesis step,we design a cost function and use the Markov Chain Monte Carlo(MCMC)method as the optimizer to solve this constrained layout ***,to make the image look natural and harmonious,we further use Poisson-based and relighting-based methods to blend foreground objects and background scene image in the post-processing *** synthesized results and comparison results based on Microsoft COCO dataset prove that our method outperforms some of the state-of-the-art methods based on generative adversarial networks(GANs)in visual quality of generated scene images.

关键词： image synthesis scene generation text-to-image conversion Markov Chain Monte Carlo(MCMC)

Low-temperature oxidation behavior and mechanism of semi-dry desulfurization ash from iron ore sintering flue gas

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Journal of Iron and Steel Research International 2021年第9期28卷 1075-1081页

作者： Yi-fan Wang Yu-dong Zhang Hong-ming Long Li-xin Qian Yun-fei luo Ru-fei Wei School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243032AnhuiChina Key Laboratory of Metallurgical Emission Reduction and Resources Recycling(Anhui University of Technology) Ministry of EducationMa'anshan 243002AnhuiChina

The low-temperature wet oxidation behavior of semi-dry desulfurization ash from iron ore sintering flue gas in ammonium citrate solution was investigated for efficiently utilizing the low-quality desulfurization ash. The effects of the ammonium citrate concentration, oxidation temperature, solid/liquid ratio, and oxidation time on the wet oxidation behavior of desulfurization ash were studied. Simultaneously, the oxidation mechanism of desulfurization ash was revealed by means of X-ray diffraction, Zeta electric resistance, and X-ray photoelectron spectroscopy (XPS) analysis. Under the optimal conditions with ammonium citrate, the oxidation ratio of CaSO_(3) was up to the maximum value (98.49%), while that of CaSO_(3) was only 8.92% without ammonium citrate. Zeta electric resistance and XPS results indicate that the dissolution process of CaSO_(3) could be significantly promoted by complexation derived from the ammonium citrate hydrolysis. As a result, the oxidation process of CaSO_(3) was transformed from particle oxidation to SO_(3)^(2−) ion oxidation, realizing the rapid transformation of desulfurization ash from CaSO_(3) to CaSO_(4) at low temperature. It provides a reference for the application of semi-dry desulfurization ash and contributes to sustainable management for semi-dry desulfurization ash.

关键词： Semi-dry desulfurization ash Ammonium citrate Calcium sulfite Calcium sulfate Wet oxidation Sintering flue gas Low-temperature oxidation

UNIFIED MODEL FOR SPLASH DROPLETS AND SUSPENDED MIST OF ATOMIZED FLOW

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Journal of Hydrodynamics 2008年第1期20卷 125-130页

作者： LIU Shi-he SUN Xiao-fei luo Jing State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

In this article, the unified mathematical model for splash droplets and suspended mist of atomized flow was established, which classifies the atomized sources into the splash source and the suspended source. For the splash source, the Lagrangian method was used to simulate the random motion of splash water droplets, and for the suspended source the theory of air-water two-phase flow was used to simulate the mist flow moving in particle clouds. The rainfall intensity of the atomized flow was obtained by summarizing the rainfall intensities relative to the above two types of atomized sources. Both experimental data and prototype observation data were used for the verification of the mathematical model. For both the distribution of rainfall intensity, and the outer edge of the atomized flow, the simulation results are in agreement with the experimental data or prototype observation data.

关键词： two phase flow atomized flow splash water drop suspended mist

Hepatic abscess resulted from a toothpick piercing the gastric wall into the liver

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Hepatobiliary & Pancreatic Diseases International 2020年第5期19卷 502-504页

作者： Cui-fei luo Jia Xu Yuan-Qiang Lu Department of Emergency Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Geriatric Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Zhejiang Provincial Key Laboratory for Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Foreign bodies’ingestion is a common phenomenon,and most of the ingested foreign bodies pass through the gut *** clinical practice,less than 1%of these patients develop complications such as gut wall penetration or perforation[1–3].We present a rare complication of hepatic abscess secondary to the toothpick piercing the gastric wall into the *** abscess was successfully treated by endoscopic retrieval of the foreign body and empirical antibiotic therapy,without drainage or laparotomy.

关键词： abscess gastric liver

Using machine learning to improve the accuracy of genomic prediction of reproduction traits in pigs

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Journal of Animal Science and Biotechnology 2022年第5期13卷 1293-1304页

作者： Xue Wang Shaolei Shi Guijiang Wang Wenxue luo Xia Wei Ao Qiu fei luo Xiangdong Ding Key Laboratory of Animal Genetics and Breeding of Ministry of Agriculture and Rural Affairs National Engineering Laboratory of Animal BreedingCollege of Animal Science and TechnologyChina Agricultural UniversityBeijingChina Hebei Province Animal Husbandry and Improved Breeds Work Station ShijiazhuangHebeiChina Zhangjiakou Dahao Heshan New Agricultural Development Co. LtdZhangjiakouHebeiChina

Background:Recently,machine learning(ML)has become attractive in genomic prediction,but its superiority in genomic prediction over conventional(ss)GBLUP methods and the choice of optimal ML methods need to be ***:In this study,2566 Chinese Yorkshire pigs with reproduction trait records were genotyped with the GenoBaits Porcine SNP 50 K and PorcineSNP50 *** ML methods,including support vector regression(SVR),kernel ridge regression(KRR),random forest(RF)and Adaboost.R2 were *** 20 replicates of fivefold cross-validation(CV)and one prediction for younger individuals,the utility of ML methods in genomic prediction was *** CV,compared with genomic BLUP(GBLUP),single-step GBLUP(ssGBLUP)and the Bayesian method BayesHE,ML methods significantly outperformed these conventional *** methods improved the genomic prediction accuracy of GBLUP,ssGBLUP,and BayesHE by 19.3%,15.0% and 20.8%,*** addition,ML methods yielded smaller mean squared error(MSE)and mean absolute error(MAE)in all *** yielded an improvement of 3.8% on average in accuracy compared to that of GBLUP,and the accuracy of BayesHE was close to that of *** genomic prediction of younger individuals,RF and Adaboost.R2_KRR performed better than GBLUP and BayesHE,while ssGBLUP performed comparably with RF,and ssGBLUP yielded slightly higher accuracy and lower MSE than Adaboost.R2_KRR in the prediction of total number of piglets born,while for number of piglets born alive,Adaboost.R2_KRR performed significantly better than *** ML methods,Adaboost.R2_KRR consistently performed well in our *** findings also demonstrated that optimal hyperparameters are useful for ML *** tuning hyperparameters in CV and in predicting genomic outcomes of younger individuals,the average improvement was 14.3% and 21.8% over those using default hyperparameters,***:Our findings demonstrated that ML methods had better

关键词： Genomic prediction Machine learning Pig Prediction accuracy