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Corrosion Behaviors of Pure Titanium and Its Weldment in Simulated Desulfurized Flue Gas Condensates in Thermal Power Plant Chimney

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 477-486页

作者： Zheng-Bing Wang hong-xiang hu Chun-Bo Liu huai-Ning Chen Yu-Gui Zheng Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences Center for Wear and Corrosion Resistant Materials Huadian Zhengzhou Mechanical Design Institute Co.Ltd. Laboratory of Properties and Reliable Joining of Welded Joints Institute of Metal ResearchChinese Academy of Sciences

The corrosion behaviors of pure titanium and its weldment welded by tungsten inert gas （TIG） welding in simulated desulfurized flue gas condensates in thermal power plant chimney were investigated using potentiodynamic polarization, electrochemical impedance spectroscopy （EIS） and immersion tests. The effects of heat input and shielding gases on the corrosion behavior of the welded titanium were also studied. Grain coarsening and Widmanst^itten structure were found in both the fusion zone and the heat-affected zone. The welded titanium exhibited active-passive behavior in the simulated condensates. Both the polarization curves and EIS measurements confirmed that TIG welding process with different parameters had few effects on the corrosion behavior. It was proved that the microstructure changes were not the key material factors affecting the corrosion behavior of pure titanium under the test conditions, while the oxide film had remarkable effect on improving the corrosion resistance.

关键词： Pure titanium Tungsten inert gas welding Simulated desulfurized flue gas condensates Corrosion behavior Microstructure Oxide film

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

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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

Near real-time gravitational wave data analysis of the massive black hole binary with TianQin

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 175-186页

作者： hong-Yu Chen xiang-Yu Lyu En-Kun Li Yi-Ming hu MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

Space-borne gravitational wave(GW)detectors can detect the merger of massive black *** early warning and localization of GW events before merging can be used to inform electromagnetic telescopes and conduct multimessenger ***,this requires real-time data transmission and analysis *** geocentric orbit of the space-borne GW detector Tian Qin makes it possible to conduct real-time data *** this study,we develop a search and localization pipeline for massive black hole binaries(MBHBs)with Tian Qin under both regular and real-time data transmission *** demonstrate that,with real-time data transmission,MBHBs can be accurately localized on the *** the approaching merger,each analysis can be finished in only 40 *** an MBHB system at a distance of 1 Gpc,if we receive data every hour,then we can pinpoint its location to within less than 1 deg^(2)on the final day before the merger.

关键词： gravitational wave detectors and experiments black holes data analysis algorithms and implementation data management

Follicle-stimulating hormone as a predictor for sperm retrieval rate in patients with nonobstructive azoospermia, a systematic review and meta-analysis

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Asian Journal of Andrology 2015年第2期17卷 281-284,I0010页

作者： Qi Yang Yan-Ping huang hong-xiang Wang Kai hu Yi-Xin Wang Yi-Ran huang Bin Chen Department of Urology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai institute of Andrology Shanghai 200127 China.

Noninvasive parameters for predicating sperm retrieval rate （SRR） are desirables. Follicle-stimulating hormone （FSH） has been an important predictor since the first years of testicular sperm extraction. Recent studies showed continuous interests in FSH, with both pros and cons. Thus, we conducted a meta-analysis to evaluate the diagnostic value of FSH as a predictor for patients with nonobstructive azoospermia （NOA） taking testicular sperm retrieval. Eligible diagnosis tests were identified from electronic databases （Cochrane Central Register of Controlled Trials, Medline, and EMBASE） without language restrictions. The database search, quality assessment, and data extraction were performed independently by two reviewers. The reference standard was the sperm retrieval result. Diagnostic value of FSH were explored by area under receiver operation characteristics （ROC） curve using Review Manager, version 5.1.0 （Cochrane Collaboration, Oxford, UK） and Meta-DiSc, version 1.4. Meta regression will be done if there is heterogeneity. Then, we find 11 tests including a total of 1350 patients met the inclusion criteria. Our pooled analysis showed that the area under ROC curve of FSH was 0.72 ~ 0.04. Meta regression analyses showed that region and average age have an influence on the diagnostic value. FSH showed more diagnostic value with patients in East Asia and with younger patients. We concluded that FSH had moderate value in independently predicating SRR in men with NOA （area under curve 〉0.7）. More detailed diagnosis tests should be anticipated in the future to confirm the diagnostic value of other noninvasive parameters.

关键词： follicule-stimulating hormone meta-analysis nonobstructive azoospermia testicular sperm retrieval

Insight of enriched basalts into the nature and evolution of mantle lithosphere beneath craton margins

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Science China Earth Sciences 2024年第10期67卷 3128-3142页

作者： hong-Kun DAI Jianping ZHENG Qing XIONG Linlin hu xiang ZHOU State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Refractory lithospheric deep roots are the cornerstone for the prolonged stability of cratons and mantle xenoliths are normally the key targets for study on the evolution of such deep roots. In regions with few mantle xenoliths, the basalts enriched in radiogenic isotopic compositions due to marked lithospheric mantle contribution are crucial to unmask the lithospheric mantle evolution based on a comprehensive study involving petrology, geochemistry and thermodynamic modelling. Here, the Early Cretaceous basalts from the northwest North China Craton with few mantle xenoliths are taken as an example to show the significance of enriched basalts on the study of lithospheric mantle. These basalts are characterized by high silica and alkali contents（SiO2=45.8–59.8 wt.%, K2O+Na2O=4.81–9.88 wt.%）, arc-type trace-element patterns and enriched radiogenic isotope compositions(e.g., εNd=-2.64–-12.88,87Sr/86Sr=0.7063–0.7093). The TiO2and FeO（total） contents are higher than those of natural and experimental melts from refractory mantle peridotite but comparable to those of partial melts of fertile mantle *** high contents of fluid-loving elements（e.g., Rb and Ba） suggest source metasomatism by aqueous fluids. Combined with thermodynamic modelling and regional tectonic history, these enriched basalts likely record simultaneous decompression melting of asthenosphere and low-extent melting of thin and fertile lithospheric mantle fluxed by aqueous fluids from the subducted Paleo-Asian oceanic slab. The newly unmasked lithospheric mantle under the western NCC contrasts with the coeval thick and refractory one supporting the eastern NCC, and highlights that the craton destruction, especially the loss of its ancient refractory mantle root, should take place in a diachronous manner related to the craton-girded subduction episodes. Our study illustrates the potential of enriched basalts to recover the nature and evolution of mantle lithosphere beneath craton margins and associated

关键词： Enriched basalts Lithospheric mantle Northwest North China Craton Tectonic histories Early Cretaceous

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R-matrix for the 8-Dimensional Spin Representation of Uq(so7)

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Acta Mathematica Sinica,English Series 2024年第2期40卷 485-497页

作者： hong Mei hu Nai hong hu School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009P.R.China School of Mathematical Sciences MOE Key Laboratory of Mathematics and Engineering Applications&Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241P.R.China

The purpose of the paper is to describe the solution to the quantum Yang-Baxter equation associated with the 8-dimensional spin representation Tsp of Uq(so7).The self-duality of Tsp and the symmetry of the corresponding braiding matrix are ***,the minimal polynomial of the braiding R-matrix of Tsp is presented explicitly in an ingenious method by taking advantage of nice features of the spin representation Tsp.

关键词： Braiding R-matrix spin module minimal polynomial

Angiosperm-wide analysis of fruit and ovary evolution aided by a new nuclear phylogeny supports association of the same ovary type with both dry and fleshy fruits

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Journal of Integrative Plant Biology 2024年第2期66卷 228-251页

作者： Yezi xiang Taikui Zhang Yiyong Zhao hongjin Dong hongyi Chen Yi hu Chien-Hsun huang Jun xiang hong Ma State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Biodiversity and Ecological EngineeringInstitute of Plant BiologyCenter of Evolutionary BiologySchool of Life SciencesFudan UniversityShanghai 200438China Department of Biology Howard Hughes Medical InstituteDuke UniversityDurhamNC 27708USA Department of Biology the Eberly College of Scienceand the Huck Institutes of the Life Sciencesthe Pennsylvania State UniversityUniversity ParkPA 16802USA hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization College of Biology and Agricultural ResourcesHuanggang Normal UniversityHuanggang 438000China

Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several orders and *** we used nuclear genes of 502 angiosperm species representing 231 families to reconstruct a well supported phylogeny,with resolved relationships for orders and families with previously uncertain *** this phylogeny as a framework,molecular dating supports a Triassic origin of the crown angiosperms,followed by the emergence of most orders in the Jurassic and Cretaceous and their rise to ecological dominance during the Cretaceous Terrestrial *** robust phylogeny allowed an examination of the evolutionary pattern of fruit and ovary types,revealing a trend of parallel carpel fusions during early diversifications in eudicots,monocots,and ***,taxa in the same order or family with the same ovary type can develop either dry or fleshy fruits with strong correlations between specific types of dry and fleshy fruits;such associations of ovary,dry and fleshy fruits define several ovaryfruit"modules"each found in multiple *** of the frequent modules has an ovary containing multiple ovules,capsules and berries,and another with an ovary having one or two ovules,achenes(or other single-seeded dry fruits)and *** new perspective of relationships among fruit types highlights the closeness of specific dry and fleshy fruit types,such as capsule and berry,that develop from the same ovary type and belong to the same module relative to dry and fleshy fruits of other modules(such as achenes and drupes).Further analyses of gene families containing known genes for ovary and fruit development identified phylogenetic nodes with multiple gene duplications,supporting a possible role of whole-genome duplications,in combination with climate changes and animal behaviors,in angiosperm fruit and ovary diversificat

关键词： angiosperm fruit evolution MADS-box molecular clock nuclear phylogeny ovary and fruit developmental genes

Continuability of Solutions for A Generalized Liénard System

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湖南大学学报(自然科学版) 1999年第6期26卷 1-8页

作者： huANG Li hong , DAI Bin xiang , hu Si hu (Dept of Applied Mathematics,hunan Univ,Changsha 410082,China) 湖南大学应用数学系湖南

Some sufficient conditions are obtained for the continuability of solutions in the future for a generalized Liénard *** known results are generalized and improved.

关键词： generalized Liénard system solution continuability

Semi-Varying Coefficient Panel Data Model with Technical Indicators Predicts Stock Returns in Financial Market

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Journal of Systems Science & Complexity 2024年第4期37卷 1638-1652页

作者： hu Xuemei PAN Ying LI xiang School of Mathematics and Statistics Chongqing Technology and Business UniversityChongqing 400067China Chongqing Key Laboratory of Social Economy and Applied Statistics Chongqing 400067China Research Center for Economy of Upper Reaches of the Yangtse River Chongqing Technology and Business UniversityChongqing 400067China

Accurately predicting stock returns is a conundrum in financial *** this conundrum can bring huge economic benefits for investors and also attract the attention of all circles of *** this paper the authors combine semi-varying coefficient model with technical analysis and statistical learning,and propose semi-varying coefficient panel data model with individual effects to explore the dynamic relations between the stock returns from five companies:CVX,DFS,EMN,LYB,and MET and five technical indicators:CCI,EMV,MOM,ln ATR,ln RSI as well as closing price(ln CP),combine semi-parametric fixed effects estimator,semi-parametric random effects estimator with the testing procedure to distinguish fixed effects(FE) from random effects(RE),and finally apply the estimated dynamic relations and the testing set to predict stock returns in December 2020 for the five *** proposed method can accommodate the varying relationship and the interactive relationship between the different technical indicators,and further enhance the prediction accuracy to stock returns.

关键词： Fixed effects random effects semi-varying coefficient panel data model stock returns technical indicators