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On the boundedness of running-in attractors based on recurrence plot and recurrence qualification analysis

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Friction 2019年第5期7卷 432-443页

作者： Guodong SUN Hua ZHU Cong DING Yu JIANG Chunling WEI School of Mechatronic Engineering China University of Mining and Technology

A feature parameter was proposed to quantitatively explore the boundedness of running-in attractors;its variation throughout the friction process was also investigated. The enclosing radius R was built with recurrence plots(RPs) and recurrence qualification analysis(RQA) by using the time delay embedding and phase space reconstruction. Additionally, the typology of RPs and the recurrence rate(RR) were investigated to verify the applicability of R in characterizing the friction process. Results showed that R is larger at the beginning, but exhibits a downward trend in the running-in friction process;R becomes smooth and trends to small steady values during the steady-state friction period, and finally shows an upward trend until failure occurs. The evolution of R, which corresponded with the typology of RPs and RR during friction process, can be used to quantitatively analyze the variation of the running-in attractors and friction state identifacation. Hence, R is a valid parameter, and the boundedness of running-in attractors can offer a new way for monitoring the friction state of tribological pairs.

关键词： running-in attractor boundedness enclosing radius recurrence plot dynamic evolvement

shinyChromosome:An R/Shiny Application for Interactive Creation of Non-circular plots of Whole Genomes

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Genomics, Proteomics & Bioinformatics 2019年第5期17卷 535-539页

作者： Yiming Yu Wen Yao Yuping Wang Fangfang Huang National Key Laboratory of Wheat and Maize Crop Science College of Life SciencesHenan Agricultural UniversityZhengzhou 450002China National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research(Wuhan)Huazhong Agricultural UniversityWuhan 430070China

Non-circular plots of whole genomes are natural representations of genomic data aligned along all chromosomes.Currently,there is no specialized graphical user interface(GUI)designed to produce non-circular whole genome diagrams,and the use of existing tools requires considerable coding effort from users.Moreover,such tools also require improvement,including the addition of new functionalities.To address these issues,we developed a new R/Shiny application,named shiny Chromosome,as a GUI for the interactive creation of non-circular whole genome diagrams.shiny Chromosome can be easily installed on personal computers for own use as well as on local or public servers for community use.Publication-quality images can be readily generated and annotated from user input using diverse widgets.shiny Chromosome is deployed at http://150.***.59.144:3838/shiny Chromosome/,http://shiny ***,and https://yimingyu.***.io/shiny Chromosome for online use.The source code and manual of shiny Chromosome are freely available at https://***/venyao/shiny Chromosome.

关键词： Genomic data visualization Non-circular whole genome plot Shiny application Graphical user interface shiny Chromosome

EXTRAPOLATING METHOD IN plot FOR FATIGUE LIFE PREDICTION OF COMPONENTS

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中国有色金属学会会刊：英文版 1996年第3期6卷 153-156页

作者： Liu Yilun Wang Ailun(College of Mechanical and Electrical Engineering,Central South University of Technology, Changsha 410083) College of Mechanical and Electrical Engineering Central South University of Technology Changsha 410083 China

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关键词： extrapolation plot fatigue life

Quantitatively distinguishing sediments from the Yangtze River and the Yellow River using δEu_N-ΣREEs plot

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Science China Earth Sciences 2009年第2期52卷 232-241页

作者： JIANG FuQing ZHOU XiaoJing LI AnChun LI TieGang Key laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Graduate University Chinese Academy of SciencesBeijing 100049China

Sediment samples were collected from the lower channel of the Yangtze River and the Yellow River and the contents of rare earth elements (REEs) were measured. In addition, some historical REEs data were collected from published literatures. Based on the δEuN-ΣREEs plot, a clear boundary was found be-tween the sediments from the two rivers. The boundary can be described as an orthogonal polynomial equation by ordinary linear regression with sediments from the Yangtze River located above the curve and sediments from the Yellow River located below the curve. To validate this method, the REEs con-tents of sediments collected from the estuaries of the Yangtze River and the Yellow River were meas-ured. In addition, the REEs data of sediment Core 255 from the Yangtze River and Core YA01 from the Yellow River were collected. Results show that the samples from the Yangtze River estuary and Core 255 almost are above the curve and most samples from the Yellow River estuary and Core YA01 are below the curve in the δEuN-ΣREEs plot. The plot and the regression equation can be used to distin-guish sediments from the Yangtze River and the Yellow River intuitively and quantitatively, and to trace the sediment provenance of the eastern seas of China. The difference between the sediments from two rivers in the δEuN-ΣREEs plot is caused by different mineral compositions and regional climate patterns of the source areas. The relationship between δEuN and ΣREEs is changed little during the transport from the source area to the river, and from river to the sea. Thus the original information on mineral compositions and climate of the source area was preserved.

关键词： sediment provenance Yangtze River Yellow River δEuN-ΣREEs plot

Optimal plot design in a multipurpose forest inventory

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Forest Ecosystems 2016年第1期3卷 37-50页

作者： Helena M.Henttonen Annika Kangas Natural Resources Institute Finland(Luke) Economics and Society unit

Background： We explore the factors affecting the optimal plot design （size and type as well as the subsample tree selection strategies within a plot） and their relative importance in defining the optimal plot design in amultipurpose forest inventory. The factors include time used to lay out the plot and to make the tree measurements within the plot, the between-plot variation of each of the variables of interest in the area, and the measurement and model errors for the different variables. Methods： We simulate different plot types and sizes and subsample tree selection strategies on measuredtest areas from North Lapland. The plot types used are fixed-radius, concentric and relascope plots. Weselect the optimal type and size first at plot level using a cost-plus-loss approach and then at cluster level byminimizing the weighted standard error with fixed budget. Results： As relascope plots are ve~/efficient at the plot level for volume and basal area, and fixed-radius plots for stems per ha, the optimal plot type strongly depends on the relative importance of these variables. The concentric plot seems to be a good compromise between these two in many cases. The subsample tree selection strategy was more important in selecting optimal plot than many other factors. In cluster level, the most important factor is the transfer time between plots. Conclusions： While the optimal radius of plots and other parameters were sensitive to the measurement times and other cost factors, the concentric plot type was optimal in almost all studied cases. Subsample tree measurement strategies need further studies, as they were an important cost factor. However, their importance to the precision was not as clear.

关键词： Sample plot Forest inventory Measurement Cost Loss

Ni(OH)_2-Ni/C for hydrogen oxidation reaction in alkaline media

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Journal of Energy Chemistry 2019年第2期28卷 111-115页

作者： Yangxin Pan Gaohe Hu Juntao Lu Li Xiao Lin Zhuang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan University

The development of the hydrogen electrode is vital for the application of alkaline polymer electrolyte fuel cells(APEFCs).In this study,a series of Ni(OH)_2 decorated Ni/C catalysts(Ni(OH)_2-Ni/C) were prepared by a three-step electrochemical treatment of Ni/C.The existence of Ni(OH)_2 was demonstrated by X-ray photoelectron spectroscopy(XPS),and the surface molar ratio of Ni(OH)_2/Ni of the samples was estimated via an electrochemical method.The HOR catalytic activity of the catalysts was evaluated by a rotation disk electrode(RDE) method,and a "volcano plot" was established between the HOR exchange current(j0) and the surface molar ratio of Ni(OH)_2/Ni.On top of the "volcano",the surface molar ratio of Ni(OH)_2/Ni is1.1:1,the j0 of which was 6.8 times of that of Ni/C.The stability of the samples toward HOR was evaluated to be good.Our study added a systematic experimental evidence to the HOR research,showing that the HOR catalytic activity of Ni can be deliberately controlled via decoration of Ni(OH)_2,which may help understanding the HOR mechanism on Ni.

关键词： Hydrogen oxidation reaction Fuel cells Alkaline polymer electrolyte fuel cells Nickel Volcano plot

Assessment of groundwater quality with special emphasis on nitrate contamination in parts of Gautam Budh Nagar district,Uttar Pradesh, India

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Acta Geochimica 2019年第5期38卷 703-717页

作者： Meenu Agarwal Meenakshi Singh Jakir Hussain Galgotias University Plot No.2Sector 17-A Yamuna ExpresswayGreater NoidaGautam Budh NagarUttar PradeshIndia National River Water Quality Laboratory Central Water CommissionNew Delhi 110016India

Progressive developments in industrial and agricultural activities are causing a critical stress on groundwater quality in developing countries.The objective of this paper is to assess and evaluate the contamination level of groundwater caused by leachate in 11 villages of the Gautam Budh Nagar district in Uttar Pradesh,India.We systematically sampled 22 groundwater samples and 13 leachate samples to ascertain the source of pollution on groundwater quality.The standard analytical methods given by the American Public Health Association(APHA)(Standard methods for examination of water and wastewater,23rd edn.APHA,AWWA,WPCF,Washington,2017)were used for quantitative estimation of hydrochemical parameters of collected samples.The results of the analysis of groundwater samples indicate that pH values range from 7.31 to 8.97.The mean magnesium concentration in groundwater samples is 58.93±21.44 mg/L.Out of the groundwater samples taken,approximately 41%and 73%of samples analysis results have been found beyond the acceptable limit with respect to the parameters of turbidity and total dissolved solids,respectively,according to the Bureau of Indian Standards(Indian standard specification for drinking water(IS:10500).BIS,Manak Bhawan,New Delhi,2012)for drinking water.Around 95.4%of groundwater samples and 92.3%of leachate samples have high nitrate concentrations above the standard limit of BIS(45 mg/L),respectively.The Piper plot shows that 50%of the samples belong to the Ca^2+-Mg^2+-HCO3^-type.Ternary and Durov's diagrams indicate that the mean concentrations of ions are in the order of Na^+>Mg^2+>Ca^2+>K^+(for cations)and HCO3^->NO3^->C1^->SO42^->CO32^->F-(for anions)in groundwater of the study area.The spatial variation of the hydrochemical parameters shows that groundwater is heavily contaminated with respect to nitrate.Analytical results indicate that the groundwater of villages Achheja,Bisrakh road,Dujana,Badalpur and Sadopur is not suitable for drinking.

关键词： Leachate Hydrochemical parameters Piper plot Ternary and Durov's diagram Spatial variation

Prospectivity modeling of porphyry copper deposits: recognition of efficient mono-and multi-element geochemical signatures in the Varzaghan district, NW Iran

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Acta Geochimica 2019年第1期38卷 131-144页

作者： Reza Ghezelbash Abbas Maghsoudi Mehrdad Daviran Faculty of Mining and Metallurgical Engineering Amirkabir University of Technology School of Mining Petroleum and Geophysics EngineeringShahrood University of Technology

The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-element geochemical anomalies associated with Cu–Au–Mo–Bi mineralization in the central parts of the Varzaghan district by applying the concentration–area fractal method. After mono-element geochemical investigations, principal component analysis was applied to ten selected elements in order to acquire a multi-element geochemical signature based on the mineralization-related component. Quantitative comparisons of the obtained fractal-based populations were carried out in accordance with known Cu occurrences using Student's t-values. Then,significant mono-and multi-element geochemical layers were separately combined with related geologic and structural layers to generate prospectivity models, using the fuzzy GAMMA approach. For quantitative evaluation of the effectiveness of different geochemical signatures in final prospectivity models, a prediction-area plot was adapted. The results show that the multi-element geochemical signature of principal component one(PC1) is more effective than mono-element layers in delimiting exploration targets related to porphyry Cu deposits.

关键词： Geochemical signature Concentration–area(C–A) fractal Principal component analysis(PCA) Student’s t-value Fuzzy mineral prospectivity modeling(MPM) Prediction–area(P–A) plot

Biomass increment and mortality losses in tropical secondary forests of Hainan, China

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Journal of Forestry Research 2019年第2期30卷 647-655页

作者： Junfu Zhao Chunsheng He Chunlin Qi Xu Wang Haiyan Deng Chunxin Wang Haiwei Liu Lianyan Yang Zhenghong Tan Institute of Tropical Agriculture and Forestry Hainan University National Natural Reserve of Diaoluoshan

Secondary forests, created after heavy logging,are an important part of China's forests. We investigated forest biomass and its accumulation rate in 38 plots in a tropical secondary forest on Hainan Island. These secondary forests are moderate carbon sinks, averaging1.96–2.17 t C ha-1 a-1. Biomass increment is largely by medium-sized(10–35 m) trees. Tree mortality accounts for almost 30% of the biomass and plays a negligible role in biomass accumulation estimates. Mortality rate is highly dependent on tree size. For small trees and seedlings, it is related to competition due to elevated irradiance after logging. Regarding prospective biomass and rates of accumulation, recovery is not as rapid as in secondary forests of cleared land. Therefore, tropical forests are susceptible to logging operations and need careful forest management.

关键词： Tropical secondary forest management Carbon sink Inventory Dynamic plot Logging