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Hierarchical adaptive stereo matching algorithm for obstacle detection with dynamic programming

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控制理论与应用（英文版） 2009年第1期7卷 41-47页

作者： Ming BAI Yan zhuang Wei wang Research Center of Information and Control Dalian University of Technology Dalian Liaoning 116024 China

An adaptive weighted stereo matching algorithm with multilevel and bidirectional dynamic programming based on ground control points （GCPs） is presented. To decrease time complexity without losing matching precision, using a multilevel search scheme, the coarse matching is processed in typical disparity space image, while the fine matching is processed in disparity-offset space image. In the upper level, GCPs are obtained by enhanced volumetric iterative algorithm enforcing the mutual constraint and the threshold constraint. Under the supervision of the highly reliable GCPs, bidirectional dynamic programming framework is employed to solve the inconsistency in the optimization path. In the lower level, to reduce running time, disparity-offset space is proposed to efficiently achieve the dense disparity image. In addition, an adaptive dual support-weight strategy is presented to aggregate matching cost, which considers photometric and geometric information. Further, post-processing algorithm can ameliorate disparity results in areas with depth discontinuities and related by occlusions using dual threshold algorithm, where missing stereo information is substituted from surrounding regions. To demonstrate the effectiveness of the algorithm, we present the two groups of experimental results for four widely used standard stereo data sets, including discussion on performance and comparison with other methods, which show that the algorithm has not only a fast speed, but also significantly improves the efficiency of holistic optimization.

关键词： Stereo matching Ground control points Adaptive weighted aggregation Bidirectional dynamic programming Obstacle detection based on stereo vision

Effect of B sites on the catalytic activities for perovskite oxides La.6Sr.4CoxFe1-xO3-δ as metal-air batteries catalysts

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Progress in Natural Science:Materials International 2018年第4期28卷 399-407页

作者： zhuang wang Siping Tan Yueping Xiong Junhua Wei MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical Engineering Harbin Institute of Technology State Key Laboratory of Advanced Chemical Power Sources

The effect of B sites on the catalytic activities of oxygen evolution reaction(OER)for perovskite oxides La0.6Sr0.4CoxFe1-xO3-δ(x=0,0.2,0.4,0.6,0.8,1,denoted as LSF,LSCF-28,LSCF-46,LSCF-64,LSCF-82 and LSC,respectively)prepared by a convenient and simple method of electrospinning technique is *** prepared La0.6Sr0.4CoxFe1-xO3-δcatalysts possess almost same crystal structures,similar morphologies(except for the LSC catalyst)and slightly different BET surface *** the optimization of the Co/Fe atomic ratio,the optimal LSCF-82 catalyst exhibits the OER performance with a low onset potential of 1.541 V,a small Tafel slope of 80.56 mV dec-1,a high charge-transfer rate and a large electrochemical surface area in 0.1 M KOH ***-82 catalyst exhibits the long-term stability under the catalytic operation condition for 12 *** catalytic activity may mainly cause by the synergy of higher catalytic activity Co and lower catalytic activity ***,the reasonable optimization of the transition metal composition in B sites for the perovskite oxides is in favor of the improvement of OER performance.

关键词： B sites La0.6Sr0.4CoxFe1-xO3-δ Perovskite oxides Oxygen evolution reaction

Impact pressure of debris flow on beam dam

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Journal of Mountain Science 2023年第10期20卷 2822-2834页

作者： wang Dong-wei YOU Yong LIU Jin-feng SUN Hao wang zhuang Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of SciencesChengdu 610041 China Institute of Mountain Hazards and Environment CASChengdu 610041China University of Chinese Academy of Science Beijing 100049China

The use of open-type check dams in mountainous areas has become common practice in order to mitigate the effects of debris flow and extend the service life of engineering *** beam dam,a common debris flow control system,has received less attention in research on the impact process of debris flow and check dams compared to solid check ***,the estimation of impact pressure in debris flow primarily considers debris flow characteristics,without taking into account the influence of geometric characteristics of the transmission *** better understand the impact process of debris flow on beam dams,a series of small-scale debris flow impact tests were conducted in a model *** parameters,including velocity,depth,and impact pressure,were *** results show that the maximum impact pressure of debris flow is affected by both the characteristics of the debris flow and the relative opening size of the beam *** to flow and edge occlusion in the middle of the beam dam,the discharge of debris flow is enhanced,resulting in a longer impact process and higher maximum impact *** on these findings,a calculation model of the maximum impact pressure of debris flow at the midpoint of the middle beam is proposed,which can be used to estimate the impact of debris flow on the discharge part of the beam dam.

关键词： Debris flow Beam dam Impact pressure Relative opening size Calculation model

Molecular engineering of C_(x)N_(y):Topologies,electronic structures and multidisciplinary applications

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Chinese Chemical Letters 2020年第12期31卷 3047-3054页

作者： Hong Yang zhuang wang Songqin Liu Yanfei Shen Yuanjian Zhang Jiangsu Engineering laboratory of Smart Carbon-Rich Materials and Device Jiangsu Province Hi-Tect key Laboratory for Bio Medical ResearchSchoo of Chemnistry and Chemical EngineeringMedical SchoolSoutheast UniversityNanjing 211189China

As a class of metal-free two-dimensional(2D)semiconductor materials,polymeric carbon nitrides have attracted wide attention recently due to its facile regulation of the molecular and electronic structures,availability in abundance and high *** to the different ratios of C and N atoms in the fra mework,a series of C_(x)N_(y)materials have been successfully synthesized by virtue of various precursors,which further triggers extensive investigations of broad applications ranging from sustainable photocatalytic reactions and highly sensitive optoelectronic *** view of topological structures on their electronic structures and material properties,the as-reported C_(x)N_(y)could be generally classified into two main categories with three-or six-bond-extending *** to the effective n→π*transition in most C_(x)N_(y)materials,the relative energy level of the lone-pair electrons on N atoms is high,which thus endows the mate rials with the capability of visible light ***,the different repeating units,bridging groups and defect sites of these two kinds of C_(x)N_(y)allow them to effectively drive a diverse of promising applications that require specific electronic,inte rfacial and geometric *** review paper aims to summarize the recent progress in topological structure design and the relevant electronic band structures and striking properties of C_(x)N_(y)materials,In the final part,we also discuss the existing challenges of C_(x)N_(y)and outlook the prospect possibilities.

关键词： Polymeric carbon nitrides C_(x)N_(y) Topology Electronic structure 2D semiconductor

Characterization of PM_(2.5)/PM_(2.5-10) and source tracking in the juncture belt between urban and rural areas of Beijing

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Chinese Science Bulletin 2009年第14期54卷 2506-2515页

作者： wang HaiLin ZHOU YuMin zhuang YaHui wang XiaoKe HAO ZhengPing Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Coarse (PM2.5-10) and fine (PM2.5) atmospheric particulate samples were collected in summer and winter during 2005―2007 in the juncture belt between urban and rural areas of Beijing. Elements, ions, organic/elemental carbon (OC/EC) and polynuclear aromatic hydrocarbons (PAHs) were determined to obtain some latest information about the particulate pollution in the juncture belt of Beijing. Particulate matter levels at this site were high as compared with the levels at other sampling sites in Beijing. Pollution elements, secondary ions and PAHs were enriched in fine particles rather than in coarse particles. An obvious seasonal variation of the chemical composition of PM was observed. Source apportionment results showed that secondary components were the largest mass contributor of PM2.5, accounting for 28%; whereas soil-related sources were the largest contributor of PM2.5-10, explaining about 49% of the total mass. The abnormal levels of soil heavy metals at the electronic waste disassembly site in the upwind villages suggested the potential impact of such activities to the environment.

关键词：农村地区北京城市 PM2.5 大气颗粒物土壤重金属追踪表征

Patterns of biomass,carbon,and nitrogen storage distribution dynamics after the invasion of pine forests by Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae) in the three Gorges Reservoir Region

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Journal of Forestry Research 2018年第2期29卷 453-464页

作者： Ruihe Gao Youqing Luo zhuang wang Hanjun Yu Juan Shi Beijing Key Laboratory for Forest Pest Control Beijing Forestry University

Masson pine stands infected by Pine wilt disease(PWD) in the Three Gorges Reservoir Region of central China were surveyed to quantify the immediate responses and subsequent trajectories of biomass,carbon(C),and nitrogen(N) in stand-level major ecosystem *** biomasses of above-and belowground tree components,as well as of the understory,forest floor,and mineral soil(0–40 cm),were determined within each stand.C and N storage were also estimated for each ecosystem *** biomass decreased steadily with the extent of PWD *** biomass ranged from1.97 to 4.16 Mg ha,and the observed value for forest floor biomass was 12.89–22.59 Mg *** highest mean C and N concentrations were found in the stem bark and needles of Masson pine,respectively,while the lowest were found in the semi-to fully decomposed layer of the forest floor and stem wood of Masson pine,*** C and N storage of aboveground trees,tree roots,and the aboveground ecosystem decreased with the extent ofPWD ***,the C and N contents of the understory,forest floor,and total mineral soil initially declined after PWD infection before recovering over the following several *** result concluded that the biomass,C,and N storage of different forest ecosystem compartments have experienced certain variations following the PWD *** is vital to understand the shifts in stand-level C and N allocation in PWD-damaged forest stands,as well as for predicting the responses of regional and global C and N cycling.

关键词： Carbon Insect outbreak Masson pine Nitrogen Pine sawyer beetle Pine wilt disease

Synthesis and photocatalytic properties of lotus-rootlike Au-ZnO nanostructures

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Science China Chemistry 2015年第5期58卷 858-862页

作者： Jia Tang Bin Zhou Shilin Zhang zhuang wang Lei Xiong Peng Li School of Chemistry and Chemical Engineering Anhui University

Unique lotus-rootlike Au-Zn O hybrid structures were obtained by controlling the deposition of pre-synthesized Au nano- crystals onto the surfaces of as-obtained Zn O structures. Zn O with lotus-rootlike structures was first prepared through a hydrothermal process. We also investigated the effects of various Au contents on the photocatalytic activities in detail. Notably, compared to the pure Zn O component, these resulting lotus-root-like Au-Zn O nanostructures with the appropriate amounts of Au content exhibited better photocatalytic efficiency.

关键词： zinc oxide gold nanocomposite hydrothermal method photocatalysis

Genome-wide analysis of the SCPL gene family in grape(Vitis vinifera L.)

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Journal of Integrative Agriculture 2021年第10期20卷 2666-2679页

作者： wang Xi-cheng WU Wei-min ZHOU Bei-bei wang zhuang-wei QIAN Ya-ming wang Bo YAN Li-chun Institute of Pomology Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic ImprovementNanjing 210014P.R.China

Serine carboxypeptidase-like(SCPL)proteins are a group of acyltransferase enzymes that have important roles in plant growth,development,and stress *** SCPL proteins have been studied in many plants,the biological functions of SCPL genes in grape are still *** this study,59 putative SCPL proteins were identified from the grape genome.A bioinformatics analysis,including chromosomal locations,exon/intron structures,phylogeny,cis-elements,and conserved motifs,was performed for the gene *** phylogenetic analysis revealed that VvSCPL proteins could be classified into three groups,with the gene motifs in each group showing high similarity *** number of exons in the VvSCPL genes ranged from 1 to 19,suggesting significant variations among grape SCPL *** expression of the VvSCPL genes,as assessed by RNA sequencing(RNA-seq)and quantitative real-time PCR,showed that most VvSCPL genes responded to drought-and waterlogging-stress treatments,which indicated their roles in abiotic stress *** results provide useful information for further study of SCPL genes in grape.

关键词： serine carboxypeptidase-like(SCPL)protein grape phylogenetic relationships abiotic stress gene expression

Machine learning guided discovery of ternary compounds involving La and immiscible Co and Pb elements

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npj Computational Materials 2022年第1期8卷 2462-2470页

作者： Renhai wang Weiyi Xia Tyler JSlade Xinyu Fan Huafeng Dong Kai-Ming Ho Paul C.Canfield Cai-zhuang wang School of Physics and Optoelectronic Engineering Guangdong University of Technology510006GuangzhouChina Department of Physics and Astronomy Iowa State UniversityAmesIA50011USA Ames Laboratory-USDOE Iowa State UniversityAmesIA50011USA Department of Physics University of Science and Technology of China230026HefeiChina

Ternary compounds with an immiscible pair of elements are relatively unexplored but promising for novel quantum materials *** what third element and its ratio that can be added to make stable ternary compounds out of an immiscible pair of elements remains a great *** this work,we combine a machine learning(ML)method with ab initio calculations to efficiently search for the energetically favorable ternary La-Co-Pb compounds containing immiscible elements Co and *** previously reported structures are correctly captured by our ***,we predict a ground state La_(3)CoPb compound and 57 low-energy La-Co-Pb ternary *** to synthesize La_(3)CoPb via multiple techniques produce mixed or multi-phases samples with,at best,ambiguous signals of the predicted lowest-energy La_(3)CoPb and the second lowest-energy La_(18)Co_(28)Pb_(3)*** calculated results of Gibbs free energy are consistent with experiments,and will provide very useful guidance for further experimental synthesis.

关键词： elements immiscible ternary