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A Weakly-Supervised Crowd Density Estimation Method Based on Two-Stage Linear Feature Calibration

IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 965-981页

作者： yong-Chao Li Rui-Sheng Jia Ying-xiang Hu Hong-Mei sun the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590 the Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266000China the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590China the College of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210000China

In a crowd density estimation dataset,the annotation of crowd locations is an extremely laborious task,and they are not taken into the evaluation *** this paper,we aim to reduce the annotation cost of crowd datasets,and propose a crowd density estimation method based on weakly-supervised learning,in the absence of crowd position supervision information,which directly reduces the number of crowds by using the number of pedestrians in the image as the supervised *** this purpose,we design a new training method,which exploits the correlation between global and local image features by incremental learning to train the ***,we design a parent-child network(PC-Net)focusing on the global and local image respectively,and propose a linear feature calibration structure to train the PC-Net simultaneously,and the child network learns feature transfer factors and feature bias weights,and uses the transfer factors and bias weights to linearly feature calibrate the features extracted from the Parent network,to improve the convergence of the network by using local features hidden in the crowd *** addition,we use the pyramid vision transformer as the backbone of the PC-Net to extract crowd features at different levels,and design a global-local feature loss function(L2).We combine it with a crowd counting loss(LC)to enhance the sensitivity of the network to crowd features during the training process,which effectively improves the accuracy of crowd density *** experimental results show that the PC-Net significantly reduces the gap between fullysupervised and weakly-supervised crowd density estimation,and outperforms the comparison methods on five datasets of Shanghai Tech Part A,ShanghaiTech Part B,UCF_CC_50,UCF_QNRF and JHU-CROWD++.

关键词： Crowd density estimation linear feature calibration vision transformer weakly-supervision learning

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Hybrid method based on flame volume concept for lean blowout limits prediction of aero engine combustors

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Chinese Journal of Aeronautics 2021年第5期34卷 425-437页

作者： Lei sun yong HUANG Xiwei WANG Zekun ZHENG Ruixiang WANG xiang FENG Collaborative Innovation Center of Advanced Air craft-Engine National Key Laboratory of Science and TechnologySchool of Energy and Power EngineeringBeihang UniversityBeijing 102206China School of Aerospace Engineering Tsin^hua UniversityBeijing 100084China China Academy of Aerospace Aerodynamics Beijing 100074China Patent Examination Cooperation(Tianjin)Center of the Patent Office CNIPATianjin 300304China

The Lean Blowout(LBO)limit is crucial for the aircraft *** semi-empirical(such as Lefebvre’s LBO model and Flame Volume(FV)model),numerical and hybrid methods are widely utilized for the LBO limit quick *** innovative hybrid method based on the FV concept is *** method can be classified as a semi-empirical/physical based hybrid prediction *** this hybrid method,it is assumed that the flame volume varies nearly linearly with the fuel/air ratio near the *** flame volume is obtained directly by the numerical simulation using the threshold value of the visible flame boundary as 900 *** the final LBO limits is determined by the FV *** the premise of keeping the good generality of prediction,the hybrid method based on the FV concept can further improve the prediction *** comparison with the prediction of the existing available methods on fifteen combustors shows that the hybrid method based on the FV concept achieves better prediction *** prediction uncertainties between the experimental results and the predicted values by the hybrid method based on the FV concept are within about±10%.

关键词： Aircraft engines Combustors Flame volume Hybrid method Lean blowout limit Prediction

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屏-片接触紧密程度与影像对比度关系的实验探讨

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泰山医学院学报 2000年第1期21卷 25-26页

作者：王昌元李月卿孙向东孙勇王军泰山医学院放射系山东泰安271000 泰安市技术监督局山东泰安271000 济南铁路分局泰安铁路医院山东泰安271000

目的　通过实验 ,对医用暗盒中屏片接触的紧密程度与X射线影像对比度关系进行探讨。方法　对金属矩形卡按不同的屏片间隔进行X射线摄影 ,得到 6张X射线照片 ,在显微密度计上对这 6张金属矩形卡像进行扫描得到 6条X射线照片的光学密... 详细信息

目的　通过实验 ,对医用暗盒中屏片接触的紧密程度与X射线影像对比度关系进行探讨。方法　对金属矩形卡按不同的屏片间隔进行X射线摄影 ,得到 6张X射线照片 ,在显微密度计上对这 6张金属矩形卡像进行扫描得到 6条X射线照片的光学密度曲线 ,根据这 6条曲线计算每张照片的对比度。结果　屏片接触越紧密 ,光学对比度越大。结论　屏片之间的紧密接触是保证X射线照片质量的重要因素之一。

关键词：屏-片接触光学对比度 X射线屏-片系统

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GOMA:functional enrichment analysis tool based on GO modules

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Chinese Journal of Cancer 2013年第4期32卷 195-204页

作者： Qiang Huang Ling-Yun Wu yong Wang xiang-sun Zhang National Center for Mathematics and Interdisciplinary Sciences Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences

Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology. A variety of enrichment analysis tools have been developed in recent years, but most output a long list of significantly enriched terms that are often redundant, making it difficult to extract the most meaningful functions. In this paper, we present GOMA, a novel enrichment analysis method based on the new concept of enriched functional Gene Ontology (GO) modules. With this method, we systematically revealed functional GO modules, i.e., groups of functionally similar GO terms, via an optimization model and then ranked them by enrichment scores. Our new method simplifies enrichment analysis results by reducing redundancy, thereby preventing inconsistent enrichment results among functionally similar terms and providing more biologically meaningful results.

关键词： GO enrichment analysis, modules, functional redundancy, network, relationships

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Ultra-broadband asymmetric acoustic transmission with single transmitted beam

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Chinese Physics B 2017年第2期26卷 288-293页

作者： Ding Jia Hong-xiang sun Shou-qa Yuan yong Ge Research Center of Fluid Machinery Engineering and Technology Faculty of Science Jiangsu University Zhenjiang 212013 China State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China

We report both experimentally and numerically that ultra-broadband asymmetric acoustic transmission is realized by a brass plate and a right triangle reflector immersed in water. This exotic phenomenon arises from the asymmetric excitation of the leaky asymmetric zero-order Lamb mode in the brass plate induced by the incident angle of external bulk waves. The results show that the bandwidth of the asymmetric acoustic transmission could reach 2000 k Hz, and the positive transmitted wave is only a single acoustic beam. The device has the advantages of ultra-broadband, single transmitted beam,and simpler structure, which has great potential applications in ultrasonic devices.

关键词： asymmetric acoustic transmission acoustic wave plate Lamb mode

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Preparation and Electrochemical Characters of Parathion Molecule Imprinted Polymeric Sensors

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Chemical Research in Chinese Universities 2011年第1期27卷 28-33页

作者： HUANG yong-xing LIAN Hui-ting sun xiang-ying LIU Bin College of Material Science and Engineering Huaqiao University Xiamen 361021 P. R. China

A sensitive, fast and low-cost molecular imprinted polymeric sensor for quantitative determination of parathion was prepared with chitosan（CS） as function matrix and parathion（PT） as template molecule via constant potential electrochemical deposition. Sensitive response was obtained with a detection limit of 1.0× 10-7 mol/L and an excellent recognition for PT was achieved due to the good memory capacity of the sensor. The developed sensor exhibited good fabrication reproducibility and acceptable stability, which provided a new promising tool for pesticide analysis.

关键词： Molecular imprinting polymer Electrochemical sensor Chitosan Parathion

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无锡市雪浪山滑坡监测及诱发因素分析

引用

世界地质 2016年第4期35卷 1164-1168页

作者：李伟宋京雷喻永祥孙立佳袁玮健江苏省地质调查研究院南京210018 国土资源部地裂缝地质灾害重点实验室南京210018 河海大学水文水资源学院南京210098 基康仪器股份有限公司北京100080 无锡市国土资源局滨湖分局无锡214000

为研究无锡市雪浪山滑坡的成因机理,在滑坡后缘岩体裂缝处布置了4支裂缝计并开展了连续监测,获取岩体裂缝1-4月份的活动性特征。监测及研究表明：边坡顺层及泥岩夹层是雪浪山滑坡的两大内因,降水及低温则是该处滑坡的两大外在诱发因素;... 详细信息

为研究无锡市雪浪山滑坡的成因机理,在滑坡后缘岩体裂缝处布置了4支裂缝计并开展了连续监测,获取岩体裂缝1-4月份的活动性特征。监测及研究表明：边坡顺层及泥岩夹层是雪浪山滑坡的两大内因,降水及低温则是该处滑坡的两大外在诱发因素;日降水量20 mm、前2 d累积降水量30-40 mm、前3 d累积降水量40-50 mm,可作为雪浪山滑坡地质灾害预警预报的临界预警指标。

关键词：地质灾害岩质滑坡监测无锡

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Template-free preparation of porous Co microfibers from spent lithium-ion batteries as a promising microwave absorber

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Rare Metals 2022年第10期41卷 3475-3485页

作者： Xiao-Min Wu Fei Xie yong-Lin Yao Yue sun Zhong-Sheng Hua Zhuo Zhao yong-xiang Yang Anhui Province Key Laboratory of Metallurgical Engineering&Resources Recycling School of Metallurgical EngineeringAnhui University of TechnologyMaanshan243002China Department of Materials Science and Engineering Delft University of TechnologyDelft2628CDNetherlands

In order to take full advantage of the secondary resources,in this paper,we reported a template-free process to prepare porous Co microfibers from spent lithiumion batteries(LIBs).First,the waste LiCoO_(2) powders were leached by oxalic acid at a suitable temperature,and rodlike cobalt oxalate powders were ***,the porous Co microfibers were prepared by using the cobalt oxalate as precursors through a thermal decomposition at420 ℃ under nitrogen *** prepared Co microfibers possess diameters of 1-2 μm,and each microfiber consists of small particles with size of100-200 *** Co microfibers(25 wt%)/paraffin composite exhibited excellent microwave absorption *** the sample thickness is 4.5 mm,the reflection losses reach-36.14 and-38.20 dB at 4.16 and 17.60 GHz,respectively,and the effective bandwidth reaches up to 5.52 *** indicates that the Co microfibers can be used as a promising microwave ***,this paper demonstrates a novel process to make a high value-added product through recycling from the spent lithium-ion *** addition,it is advantageous to eliminate the hazard of spent lithium-ion batteries and electromagnetic radiation to environment and human health.

关键词： Spent lithium-ion batteries(LIBs) Co microfibers Recycling Oxalic acid leaching Microwave absorption

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Reaction degree of composition B explosive with multi-layered compound structure protection subjected to detonation loading

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Defence Technology（防务技术） 2021年第2期17卷 315-326页

作者： Jia-yun Liu yong-xiang Dong Xuan-yi An Ping Ye Qi-tian sun Qian Gao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The explosive reaction degree and protection from explosions are concerns in the military *** this work,the reaction degree of the composition B explosive was investigated ***-layered compound structures were used as barriers to weaken the blast loads.A comprehensive experiment using a high-speed camera and image processing techniques,side witness plates,and bottom witness plates was *** the experimental fragment velocities,fragment piercing patterns,and damage characteristics,the reaction degree of the explosive impeded by different multi-layered compound structures could be precisely *** parameters of the explosive obstructed by compound structures were obtained by theoretical analysis and numerical *** the common method in which the explosive reaction degree is only distinguished based on the initial pressure amplitude transmitted into the explosive,a following shock wave reflected from the side steel casing was also *** detonation growth paths in the explosive ***,all these shock wave propagation characteristics must be considered to analyze the explosive response impeded by compound structures.

关键词： Reaction degree Explosive protection Compound structure Comprehensive experiment

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Oscillatory Periodic Solutions of Nonlinear Second Order Ordinary Differential Equations

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Acta Mathematica Sinica,English Series 2005年第3期21卷 491-496页

作者： yong xiang LI Department of Mathematics Northwest Normal University Lanzhou 730070 P. R. China

In this paper the existence results of oscillatory periodic solutions are obtained for a second order ordinary differential equation -u″（t） = f（t, u（t））, where f ： R^2 → R is a continuous odd function and is ... 详细信息

关键词： Second order differential equation Oscillatory periodic solution Cone Fixed point index

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