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Evaluation of Dissolved Organic Carbon Using Synchronized Fluorescence Emission Spectra and Unsupervised Method of Principal Component Analysis (PCA) and Independent Component Analysis (ICA)

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journal of Water Resource and Protection 2019年第3期11卷 244-279页

作者： Tais Cristina Filippe Luana Mayumi Takahasi Marques Heloise G. Knapik júlio César Rodrigues de Azevedo jorge Costa Pereira department of Chemistry and Biology Federal University of Technology—Paraná Curitiba Brazil department of Hydraulic and Sanitation Federal University of Technology—Paraná Curitiba Brazil department of Chemistry University of Coimbra Coimbra Portugal

Dissolved organic matter (DOM) can be originated from autochthonous or allochthonous sources, where allochthonous DOM can be from pedogenic sources (humic substances—HSs) or anthropogenicsources (wastewater). The analysis of fluorescence emission, excitation, synchronous or excitation-emission matrix (EEM) have been used to identify the main source or probable contribution of dissolved compounds, such as humic acids (HA), fulvic acids (FA) and dissolved organic carbon (DOC) from sewage, but does not quantify. Fluorescence emission is a powerful technique to detect and qualify organic dissolved compounds but fails in quantitative aspects. In this work, we propose an in situ method for direct determination of DOC using synchronous fluorescence spectra with independent component analysis (ICA). Well known standard solutions were used for method development and validation. In this work, we show that it is possible to predict the number of independent contributions using an unsupervised method based on iterative Principal Component Analysis and Independent Component Analysis (PCA-ICA) approach over combined matrix results. Within these results it’s also possible to see that with a very small amount of independent components it is possible to describe environmental samples of HA, FA and primary productivity (PP).

关键词： Independent Component Analysis Dissolved Organic Carbon Spectra deconvolution Synchronized Fluorescence

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Volcano video data characterized and classified using computer vision and machine learning algorithms

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Geoscience Frontiers 2020年第5期11卷 1789-1803页

作者： Alex j.C.Witsil jeffrey B.johnson department of Geosciences Boise State UniversityBoiseIDUSA

Video cameras are common at volcano observatories,but their utility is often limited during periods of crisis due to the large data volume from continuous acquisition and time requirements for manual *** cameras to serve as effective monitoring tools,video frames must be synthesized into relevant time series signals and further analyzed to classify and characterize observable *** this study,we use computer vision and machine learning algorithms to identify periods of volcanic activity and quantify plume rise velocities from video *** were collected at Villarrica Volcano,Chile from two visible band cameras located^17 km from the vent that recorded at 0.1 and 30 frames per second between February and April *** these two months,Villarrica exhibited a diverse range of eruptive activity,including a paroxysmal eruption on 3 *** to and after the eruption,activity included nighttime incandescence,dark and light emissions,inactivity,and periods of cloud *** quantify the color and spatial extent of plume emissions using a blob detection algorithm,whose outputs are fed into a trained artificial neural network that categorizes the observable activity into five *** shifts from primarily nighttime incandescence to ash emissions following the 3 March paroxysm,which likely relates to the reemergence of the buried lava *** periods exhibiting plume emissions are further analyzed using a row and column projection algorithm that identifies plume onsets and calculates apparent plume horizontal and vertical rise *** onsets are episodic,occurring with an average period of^50 s and suggests a puffing style of degassing,which is commonly observed at ***,the lack of clear acoustic transients in the accompanying infrasound record suggests puffing may be controlled by atmospheric effects rather than a degassing regime at the *** presented here offer a generalized toolset for volcano monito

关键词： Volcano monitoring Plume exit velocity Volcano webcam Image processing Machine learning Villarrica

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Alternative expressions for stand diameter in complex forests

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Forest Ecosystems 2023年第3期10卷 328-336页

作者： Mark j.Ducey john A.Kershaw jr. department of Natural Resources and the Environment University of New HampshireDurhamNHUSA Faculty of Forestry and Environmental Management University of New BrunswickFrederictonNBCanada

Quadratic mean diameter is the most frequently reported descriptor of the diameter distribution of *** such,it is often used as an indicator of forest stand structure,developmental stage,and ecological and economic ***,quadratic mean diameter can be heavily influenced by the presence or absence of large numbers of small stems in lower canopy strata,and it is also sensitive to left-truncation of the diameter distribution,making its interpretation across inventories with different protocols ***,we examine three alternative expressions of stand diameter:the arithmetic and quadratic mean diameter of the thickest 100 trees per hectare,and the basal area-weighted mean *** data from the United States Forest Inventory and Analysis program for New York and New England,these alternative expressions showed closer correlation with multiple stand structural variables than did quadratic mean diameter,including merchantable cubic and board foot volume per hectare,aboveground live tree carbon per hectare,and total number of live and dead standing trees greater than 40 cm diameter at breast height per hectare(previously proposed as an index of old-growth structure).Arithmetic and quadratic mean diameter of the thickest 100 trees per hectare showed nearly identical performance,and the strongest correlations across the *** develop closed-form expressions for these variables when the diameter distribution is a Weibull,and illustrate their behavior relative to quadratic mean diameter for that *** the reasons for prevalence of quadratic mean diameter as an indicator remain valid,we suggest that these alternative measures should be more widely reported and analyzed to give a more informative depiction of stand structure and development in complex forests.

关键词： Forest structure Diameter at breast height Weibull distribution

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麻风患者对卡介苗接种之影响

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中华皮肤科杂志 1959年第2期7卷 114-115+122页

作者： j. Van de Heyning LU Xinyi 沈阳医学院第二医院皮膚科

作者在Wafomia, Congo Belge对麻风病人初步进行了研究.300病人接受了麻风菌素试验(用Wade氏法),于21天后观察反应(或Mitsuda反应).

关键词：卡介苗麻风

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Kinematic analysis of penile reflexes in a rat model of spinal cord injury

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Asian journal of Andrology 2021年第1期23卷 30-35页

作者： Casey j Steadman Sai S Vangoor Charles H Hubscher department of Anatomical Sciences and Neurobiology University of LouisvilleLouisvilleKY 40202USA Kentucky Spinal Cord Injury Research Center LouisvilleKY 40202USA.

The ex-copula penile dorsiflexion reflex(PDFR)is an established measure of sexual dysfunction in male rat models of spinal cord *** the PDFR after complete spinal transection is well described,information regarding the more clinically relevant incomplete spinal contusion injury model is *** study examined,using two-dimensional(2D)kinematic analysis,the relationship between the PDFR and degree of white matter sparing(WMS).Male Wistar rats received a T9 contusion with varying degrees of impactor *** kinematic recordings of the PDFR were made 3-8 weeks *** reflex components examined included maximum angle of penile dorsiflexion,total penile event duration,and penile ascent *** hoc comparison between animals grouped based upon injury severity(moderate-severe:13.33%-17.15%WMS vs moderate:20.85%-33.50%WMS)ndicated PDFR ***,the numbers of animals with more moderate contusions having data points above the median n both maximum angle of penile dorsiflexion and penile ascent speed were significantly lower than animals with more severe *** penile event duration was also affected but only at more chronic time points(6-8 weeks).Thus,2D kinematic analysis of the PDFR allows for more consistent and quantifiable analysis of the subtle differences that can occur between injury severity groups in the rat contusion model.

关键词： erection penile sexual dysfunction spinal cord injury

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NEW MURID ROdeNTS FROM THE LATE CENOZOIC OF YUSHE BASIN, SHANXI

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古脊椎动物学报(中英文） 1992年第1期 29-38+87-88页

作者： Lawrence j.Flynn Harvard University NY Research Associate American Museum of Natural History and Peabody Museum

As scientific collaborators of the Chinese-American joint project "Neogene Rocks and Faunas, Yushe Basin, Shanxi, PRC", the present authors, with William R. Downs, Northern Arizona University, sampled the Yushe microfauna in the fall of 1987 and 1988. The fossil temains were retrieved by surface collection and by wet-sieving bulk quantities of sediment.

关键词： Yushe Basin Late cenozoic murids new taxa

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Incorporation of meat quality and use of ultrasound technology for swine genetic improvement programs

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华南农业大学学报 2005年第S1期26卷 88-98页

作者： Tom j.BAAS department of Animal Science Iowa State UniversityUSA

Real-time ultrasound has been, and will continue to be, one of the most important tools in enhancing genetic improvement in the U.S. Recent advancements in the technology have allowed ultrasound to be used in evaluating intramuscular fat in live animals. Together with other genetic improvement tools, ultrasound technology will offer seedstock producers the opportunity to select for improved IMF in potential breeding stock replacements and hence speed genetic progress for the improvement of this trait. After three generations of selection for IMF using real-time ultrasound in an Iowa State University study, the average EBV for select line pigs is 0.83% greater than for control line pigs. Selection for IMF has, however, resulted in slightly more backfat and less loin muscle area, and a trend toward more days to 114 kg in the select line compared to the control line. Carcass evaluation of a sample of pigs from each litter indicated a similar increase in IMF, increase in backfat, and reduction in loin muscle area for select line pigs. No differences were found for Hunter L* color, Minolta reflectance, and ultimate pH.

关键词： swine meat quality intramuscular fat ultrasound technology

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求解下料问题的一种算法

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兵工学报 2005年第5期26卷 670-674页

作者：周培德北京理工大学信息科学技术学院北京100081

给出各种模块的定义,并证明了它们的某些性质。在此基础上设计求解下料问题的一种算法,该算法首先处理基本模块,然后分2种不同情况构造基本模块的布局。分析了算法的复杂性和普遍性。列举3个计算实例,其裁剪率较为满意。

关键词：计算机科学技术基础学科下料问题基本模块模块的布局算法复杂性

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Heavy Metals in a Sulfldic Minespoil: Fractions and Column Leaching

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Pedosphere 2003年第1期13卷 75-80页

作者： C.LIN j.LIN School of Enviornmental Scienceand Management Southern Cross University Lismore NSW 澳大利亚

Fractions of various heavy metals in a sulfidic minespoil were investigated. Column leaching experimentwas also conducted to simulate 'acid mine drainage' (AMD) from the minespoil. The results show thatleaching of heavy metals from the minespoil was extremely significant during the initial water *** amounts of heavy metals leached out dramatically reduced after leaching twice. It is worthwhile tonote that in this study, Zn, Mn, Fe, As and Ni in the first leachate exceeded the total amount of eachcorresponding water-extractable (1:5, soil:water) metal contained in the minespoil sample. This appears tosuggest that 1:5 water extraction did not allow accurate estimation of water-leachable concentrations of theabove heavy metals. This work has implications for the management of sulfidic minespoils. Acid drainageof great environmental concerns is likely to occur only during heavy rainfall events after substantial solubleand readily exchangeable acid and metals are accumulated in the minespoils. The slow-reacting fractionsother than water-soluble and readily exchangeable fractions may pose little environmental hazards. This isparticularly true for Pb, As and Ni.

关键词： acid mine drainage heavy metal leaching metal sulfides minespoil

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Analysis of Surface Integrity in Drilling Metal Matrix and Hybrid Metal Matrix Composites

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journal of Materials Science & Technology 2012年第8期28卷 761-768页

作者： T.Rajmohan K.Palanikumar j.Paulo Davim department of Mechanical Engineering Sri Chandrasekharendra Saraswathi Viswa Maha Vidyalaya University department of Mechanical Engineering Sri Sai Ram Institute of Technology department of Mechanical Engineering University of AveiroCampus Santiago3810-193 AveiroPortugal

Hybrid metal matrix composites consist of at least three constituents-a metal or an alloy matrix and two reinforcements in various forms, bonded together at the atomic level in the composite. despite their higher specific properties of strength and stiffness, the non homogeneous and anisotropic nature combined with the abrasive reinforcements render their machining difficult. In this paper, the surface integrity of machining in drilling hybrid composites has been discussed. Drilling tests are carried out at different spindle speed, feed rates, and different drill tool materials to investigate the effect of the various cutting parameters on the surface quality and the extent of the deformation of drilled surface due to drilling. Materials used for the present investigation are A1356/IOSIC （wt%） metal matrix and A1356/10SiC-3mica （wt%） hybrid composites. The composites are fabricated using stir casting route. The drilling tests are conducted on vertical computer numeric control （CNC） machining center using carbide, coated carbide and polycrystalline diamond （PCD） drills. The surface roughness decreases with increasing spindle speed and increases with increasing feed rate. The machined surface is analyzed by scanning electron microscopy （SEM）. SEM images of the machined surfaces indicate the presence of grooves and pits. Microhardness depth profiles indicate that the subsurface damage is limited to the top of 100-250 μm.

关键词： Hybrid composites Scanning electron microscopy (SEM) Subsurface Drilling

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