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KEYHOLE IMAGE PROCESSING OF VARIABLE POLARITY PLASMA ARC WELDING BASED ON WAVELET TRANSFORM

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Chinese Journal of Mechanical Engineering 2001年第1期14卷 62-66+73页

作者： Liu zhonghua Wang Qilong zhu Jiaqi Welding Department, Harbin Institute of Technology 哈尔滨工业大学黑龙江哈尔滨

In order to realize the feedback control for variable polarity plasma arc welding (VPPAW) formation in the welding process, the geometrical sizes of the keyhole image must be extracted. With the properties of multiscale edge through the wavelet theory, the edge points were detected by getting the maximum modules of the gradient vector in the dircetion towards which the gradient vector points in the image plane. At coarse scales, the local maxima of modules have different positions and only detected the sharp edge. At fine scale, there are many maxima created by the image noise. The best scale where the edges are well discriminated from noises is discussed by the multiscale transform. At last, a new method of peak analysis for threshold selection is provided. It is based on the wavelet transform which provides a multiscale analysis of the information of the histogram. Many experiments show these ways are effective for the keyhole image to get the geometry parameters of the keyhole in the real time VPPAW image processing.

关键词： PAW Variable polarity Keyhole Image

A Recommendation Mechanism for Web Publishing Based on Sentiment Analysis of Microblog

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Wuhan University Journal of Natural Sciences 2015年第2期20卷 146-152页

作者： TIAN Pingfang zhu zhonghua XIONG Li XU Fangfang College of Computer Science and Technology Wuhan University of Science and Technology Intelligent Information Processing and Real-time Industrial System Hubei Province Key Laboratory

Microblog is a social platform with huge user community and mass data. We propose a semantic recommendation mechanism based on sentiment analysis for microblog. Firstly, the keywords and sensibility words in this mechanism are extracted by natural language processing including segmentation, lexical analysis and strategy selection. Then, we query the background knowledge base based on linked open data （LOD） with the basic information of users. The experiment result shows that the accuracy of recommendation is within the range of 70% -89% with sentiment analysis and semantic query. Compared with traditional recommendation method, this method can satisfy users＇ requirement greatly.

关键词： sentiment analysis microblog keyword extraction linked open data background knowledge base

Tuning oxygen vacancies in two-dimensional iron-cobalt oxide nanosheets through hydrogenation for enhanced oxygen evolution activity

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Nano Research 2018年第6期11卷 3509-3518页

作者： Linzhou zhuang Yi Jia Tianwei He Aijun Du Xuecheng Yan Lei Ge zhonghua zhu Xiangdong Yao School of Chemical Engineering The University of Queensland Brisbane 4072 Australia School of Environment and Science and Queensland Micro- and Nanotechnology Centre Griffith University Nathan Campus Brisbane 4111 Australia School of Chemistry Physics and Mechanical Engineering Queensland University of Technology Gardens Point Campus Brisbane 4001 Australia

The oxygen evolution reaction （OER） represents the rate-determining step of electrocatalytic water splitting into hydrogen and oxygen. Creating oxygen vacancies and adjusting their density has proven to be an effective strategy to design high-performance OER catalysts. Herein, a hydrogenation method is applied to treat a two-dimensional （2D） iron-cobalt oxide （Fe1Co1Ox-origin）, with the purpose of tuning its oxygen vacancy density. Notably, compared with Fe1Co1Ox-origin, the iron-cobalt oxide hydrogenated at 200℃ and 2.0 MPa optimized conditions exhibits a markedly improved OER activity in 1.0 M KOH （with an overpotential 17 of 225 mV at a current density of 10 ***^-2） and a rapid reaction kinetics （with a Tafel slope of 36.0 mV·dec^-1）. Moreover, the OER mass activity of the hydrogenated oxide is 1.9 times that of Fe1Co1Ox-origin at an overpotential of 350 mV. The experimental results, combined with density functional theory （DFT） calculations, reveal that the optimal control of oxygen vacancies in 2D Fe1Co1Ox via hydrogenation can improve the electronic conductivity and promote OH- adsorption onto nearby low-coordinated Co^3＋ sites, resulting in a significantly enhanced OER activity.

关键词： hydrogenation tuning oxygen vacancy oxygen evolution reaction

A 3D convolutional neural network model with multiple outputs for simultaneously estimating the reactive transport parameters of sandstone from its CT images

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Artificial Intelligence in Geosciences

Artificial Intelligence in Geosciences 2024年第1期5卷 310-319页

作者： Haiying Fu Shuai Wang Guicheng He zhonghua zhu Qing Yu Dexin Ding Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang421001PR China School of Resource Environment and Safety Engineering University of South ChinaHengyang421001PR China

Porosity,tortuosity,specific surface area(SSA),and permeability are four key parameters of reactive transport modeling in sandstone,which are important for understanding solute transport and geochemical reaction pro-cesses in sandstone *** four parameters reflect the characteristics of pore structure of sandstone from different perspectives,and the traditional empirical formulas cannot make accurate predictions of them due to their complexity and *** this paper,eleven types of sandstone CT images were firstly segmented into numerous subsample images,the porosity,tortuosity,SSA,and permeability of the subsamples were calculated,and the dataset was *** 3D convolutional neural network(CNN)models were subse-quently established and trained to predict the key reactive transport parameters based on subsample CT images of *** results demonstrated that the 3D CNN model with multiple outputs exhibited excellent prediction ability for the four parameters compared to the traditional empirical *** particular,for the prediction of tortuosity and permeability,the 3D CNN model with multiple outputs even showed slightly better prediction ability than its single-output variant ***,it demonstrated good generalization per-formance on sandstone CT images not included in the training *** study showed that the 3D CNN model with multiple outputs has the advantages of simplifying operation and saving computational resources,which has the prospect of popularization and application.

关键词： Reactive transport CNN model with multiple outputs Sandstone Tortuosity Permeability

A THROUGHPUT-EFFICIENT ADAPTIVE TRANSMIT-RECEIVE SCHEME FOR INDOOR DS-UWB SYSTEMS

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Journal of Electronics(China) 2008年第1期25卷 39-46页

作者： Liang zhonghua zhu Shihua Wang Shaopeng School of Electronics and Information Engineering Xi＇an Jiaotong University Xi＇an 710049 China

In this paper, a novel adaptive transmit-receive scheme is presented for indoor Direct Se- quence Ultra-WideBand (DS-UWB) systems. In the proposed scheme, a simple switch module is in- troduced to improve the system throughput. Furthermore, adaptive detection is implemented via an improved Least Mean Squares (LMS) algorithm. The convergence behavior and the Bit Error Rate (BER) performance of the proposed scheme are examined under the realistic channel models. Simu- lation results show that, nearly without loss of the BER performance, the proposed scheme can obtain at least 2/3 improvement in training overhead compared with the conventional approach.

关键词： Ultra-WideBand (UWB) Adaptive detection Dense multipath Wireless Personal Area Networks (WPANs)

Preparation and up-conversion luminescence properties of Er:YbAG and Er:YAG single crystals

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Journal of Materials Science & Technology 2024年第18期185卷 1-8页

作者： Limin Wu Zeyu Cheng Shoulei Xu Wenxia Wu Yazhao Wang Huiting Zhang zhonghua zhu Ninghan Zeng Bernard Albert Goodman Wen Deng School of Physical Science and Technology Guangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Nanning530004China

High quality optical single crystals of cubic Yb_(2.96)Er_(0.04)Al_(5)O_(12)and Y_(2.96)Er_(0.04)A_(l5)O_(12)were successfully pre-pared using the OFZ *** 980 nm photon absorption intensity by Yb_(2.96)Er_(0.04)Al_(5)O_(12)crystal is much larger than that in Y_(2.96)Er_(0.04)A_(l5)O_(12)crystal,the transmission of Yb_(2.96)Er_(0.04)Al_(5)O_(12)crystal is lower than that of Y_(2.96)Er_(0.04)A_(l5)O_(12)crystal,because the density of Yb_(2.96)Er_(0.04)Al_(5)O_(12)single crystal(6.604 g/cm^(3))is larger than that of Y_(2.96)Er_(0.04)A_(l5)O_(12)single crystal(4.529 g/cm^(3)).The up-conversion luminescence spec-tra of the crystals excited by 980 nm laser show several distinct groups of emission peaks at-544 and-556 nm,as well as-650 and-667 *** peak intensities of the up-conversion luminescence spec-trum for the Yb_(2.96)Er_(0.04)Al_(5)O_(12)crystal were much higher than those for the Y_(2.96)Er_(0.04)A_(l5)O_(12)***-all,the results of the present study suggest that Yb_(2.96)Er_(0.04)Al_(5)O_(12)single crystal may have advantages over Y_(2.96)Er_(0.04)A_(l5)O_(12)single crystal for luminescence in solid-state lasers.

关键词： YbAG single crystals Up-conversion luminescence Rare earth ions

高活性抗CO2中毒中温固体氧化物燃料电池阴极

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物理化学学报 2016年第8期32卷 1856-1857页

作者： zhu zhonghua School 0f Chemical Engineering The University of Queensland Brisbane QLD 4072 Australia

过度开发和使用化石能源造成了目前世界能源短缺，并且导致了严重的环境污染。为了实现人类的可持续发展，开发和利用经济、洁净的新能源是21世纪世界能源科技的主题。固体氧化物燃料电池（SOFC）是一种高效、清洁、环境友好、

关键词：中温固体氧化物燃料电池 CO2 高活性阴极中毒过度开发可持续发展能源短缺

The Ideal Directions for the Advancement of Building an Ecological Civilization in the New Era: From Creating a Better Life for the Chinese People to Global Ecological Governance

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Contemporary Social Sciences 2019年第2期4卷 145-155页

作者： Huang Qiusheng zhu zhonghua Wu Lingwei School of Marxism University of South China 不详

According to the report to the 19th CPC National Congress, socialism with Chinese characteristics entered a new era with the specified strategical task of building China into a great modern socialist country that is prosperous, strong, democratic, culturally advanced, harmonious and beautiful. The report also stressed that building an ecological civilization is vital to sustaining the Chinese nation's development. Against such a backdrop, it is necessary to analyze the "building of an ecological civilization" from three directions, i.e. satisfying people's requirement for a better life, fulfilling the goal of the Beautiful China Initiative and taking the lead in global ecological governance. This is an inevitable requirement for the advancement of the harmonious coexistence between man and nature and at the same time corresponds to the internal demand for the implementation of Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era.

关键词： new era ecological civilization a community of shared life a community with a shared future for mankind

One-step In-situ Synthesis of Vacancy-rich CoFe2O4@Defective Graphene Hybrids as Bifunctional Oxygen Electrocatalysts for Rechargeable Zn-Air Batteries

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Chemical Research in Chinese Universities 2020年第3期36卷 479-487页

作者： WANG X in zhuANG Linzhou JIA Yi ZHANG Lijie YANG Qin XU Wenjia YANG Dongjiang YAN Xuecheng ZHANG Longzhou zhu zhonghua BROWN Christopher L YUAN Pei YAO Xiangdong School of Environment and Science ami Queensland Micro-and Nanotechnology CentreGriffith UniversityNathan CampusQueensland 4111Australia School of Chemistry Physics and Mechanical EngineeringQueensland University of TechnologyBrisbaneQueensland 4000Australia Collaborative Innovation Center for Mahne Biomass Fibers Materials ami Textiles of Shandong ProvinceInstitute of Marine Biobased MaterialsCollege of Environmental Science and EngineeringQingdao UniversityQingdao 266071P.R.China National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350002P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012P.R.China

Developing efficient catalysts toward both oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is the core task for rechargeable metal-air *** integration of two active components should be an effective method to produce the bifunctional catalysts in principle,traditional techniques still can not attain fine tunable surface structure during material-hybridization ***,we present a facile short-time in-situ argon(Ar)plasma strategy to fabricate a high-performance bifunctional hybrid catalyst of vacancy-rich CoFe2O4 synergized with defective graphence(r-CoFe2O4@DG).Reflected by the low voltage gap of 0.79V in two half-reaction measurements,the striking capability to catalyze ORR/OER endows it excellent and durable performance in rechargeable Zn-air batteries,with a maximum power density of 155.2mW/cm^2 and robust stablility(up to 60h).Further experimental and theoretical studies validate its remarkable bifunctional energetics root from plasma-induced surface vacancy defects and interfacial charge polarization between DG and CoFe2O4.

关键词： Defect CoFe2O4 Oxygen reduction Oxygen evolution Zn-air battery