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A new method of calculating crown projection area and its comparative accuracy with conventional calculations for asymmetric tree crowns

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Journal of Forestry Research 2024年第4期35卷 171-188页

作者： Mingrui Zhang Huiquan Bi Xingji Jin Michael mclean School of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Forest Science NSW Department of Primary IndustriesLevel 304PSQ12 Darcy StreetParramattaNSW 2150Australia School of Ecosystem and Forest Sciences The University of MelbourneMelbourne 3010Australia

This paper introduces a new method of calculating crown projection area(CPA),the area of level ground covered by a vertical projection of a tree crown from measured crown radii through numerical interpolation and *** novel method and other four existing methods of calculating CPA were compared using detailed crown radius measurements from 30 tall trees of Eucalyptus pilularis variable in crown size,shape,and *** four existing methods included the polygonal approach and three ways of calculating CPA as the area of a circle using the arithmetic,geometric and quadratic mean *** were made across a sequence of eight non-consecutive numbers(from 2 to 16)of measured crown radii for each tree over the range of crown asymmetry of the 30 trees through generalized linear models and multiple comparisons of *** sequence covered the range of the number of crown radii measured for calculating the CPA of a tree in the literature.A crown asymmetry index within the unit interval was calculated for each tree to serve as a normative *** a slight overestimation of 2.2%on average and an overall mean error size of 7.9%across the numbers of crown radii that were compared,our new method was the least biased and most *** CPA as a circle using the quadratic mean crown radius was the second best,which had an average overestimation of 4.5%and overall mean error size of 8.8%.These two methods remained by and large unbiased as crown asymmetry increased,while the other three methods showed larger bias of *** the conventional method of using the arithmetic mean crown radius to calculate CPA as a circle,bias correction factors were developed as a function of crown asymmetry index to delineate the increasing magnitude of bias associated with greater degrees of crown *** study reveals and demonstrates such relationships between the accuracy of CPA calculations and crown asymmetry and will help increase awa

关键词： Crown radius measurements Interpolated crown contour Projected crown area Multiple comparisons of means

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Normal Crossings Singularities for Symplectic Topology:Structures

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Acta Mathematica Sinica,English Series 2024年第1期40卷 107-160页

作者： Mohammad FARAJZADEH-TEHRANI Mark mclean Aleksey ZINGER The University of Iowa MacLean HallIowa CityIA 52241 Department of Mathematics Stony Brook UniversityStony BrookNY 11794

Our previous papers introduce topological notions of normal crossings symplectic divisor and variety,show that they are equivalent,in a suitable sense,to the corresponding geometric notions,and establish a topological smoothability criterion for normal crossings symplectic *** present paper constructs a blowup,a complex line bundle,and a logarithmic tangent bundle naturally associated with a normal crossings symplectic divisor and determines the Chern class of the last *** structures have applications in constructions and analysis of various moduli *** a corollary of the Chern class formula for the logarithmic tangent bundle,we refine Aluffi’s formula for the Chern class of the tangent bundle of the blowup at a complete intersection to account for the torsion and extend it to the blowup at the deepest stratum of an arbitrary normal crossings divisor.

关键词： Normal crossings divisor Chern class Logarithmic tangent bundle

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Seasonal changes in Hermit Thrush (Catharus guttatus) song syntax

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Avian Research 2024年第2期15卷 172-179页

作者： Sean P.Roach Luke C.mclean Jeff W.MacLeod Leslie S.Phillmore Psychology Department University of New Brunswick Saint John100 Tucker Park RoadSaint JohnNBCanada Department of Psychology and Neuroscience Dalhousie University1355 Oxford StHalifaxNSB3H 4J1Canada

In many songbird species,birdsong features phonological syntax,meaning that the units within their vocal se-quences are ordered in a non-random way that adheres to a *** such syntactical patterns have been richly described in many species,comparatively little is known about how those patterns contribute to song achieving its important *** each of song’s main functions,territorial defense and mate attraction,evidence of a role for syntax is *** species for which syntax has been thoroughly described is the Hermit Thrush(Catharus guttatus),which presents song types from their repertoires in a semi-predictable order and,in doing so,rapidly cycle up and down the frequency *** objective of the present study was to explore the importance of song syntax in the Hermit Thrush through a within-subject examination of how measures of syntax,such as the predictability of song type order within song sequences,shift over the breeding *** hypothesized that,if such syntactical characteristics are important to breeding behaviour,they would be most prominent at the start of the breeding season when activity associated with territory establishment and mate attraction is most *** revealed that,as predicted,the rigidness of song type ordering within se-quences was highest at the start of the season and declined *** song type sequences were most predictable at the vitally important early part of the breeding season fit our hypothesis that this aspect of song syntax is important to song’s functions related to territory establishment and/or mate *** work will clarify whether that role relates to one of song’s two main functions or serves song transmission in some broader way.

关键词： Birdsong Hermit Thrush Seasonal change Stereotypy Syntax

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Windows 2000 TCP/IP技术内幕 G

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丛书名：软件开发技术丛书

2001年

作者：（美）Ian mclean 王建华等译

本书对Windows 2000下的TCP/IP协议进行了全面系统的介绍。每一章的内容可分为两部分。第一部分是理论概念的深入介绍，第二部分则讲述各种协议的具体操作方法。

ISBN: (纸本)7111093437

关键词：计算机互连网络协议

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Desulphurization of Hot Metal and Ferronickel With Calcium Aluminate Fluxes

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Journal of Iron and Steel Research International 2011年第S2期18卷 74-83页

作者： mclean Alex BARATI Mansoor Department of Material Science and Engineering University of Toronto Ontario Canada M5S 3E4

Traditionally, fluxes containing calcium fluoride and other additives are used for the treatment of hot metal and molten steel. Recently, magnesium powder or lime-Mg mixture is used more popularly in hot metal desulphurization. However, the use of calcium fluoride has been restricted due to environmental concerns, and the supply of magnesium is uncertain for the countries, which are short of magnesium resource. For those reasons, calcium aluminate fluxes are a possible alternative to replace slags containing calcium fluoride or magnesium. Calcium aluminate fluxes can be produced from three different raw materials: (1) high-quality bauxite, (2) residuals from aluminum dross treatment processes and (3) waste products from alumina production. Due to the limited amount and high cost associated with high-quality bauxite, the other two sources are preferred based on both economic and environmental considerations. The objective of this paper is to examine the use of waste slags and by-products from the aluminum industry as potential refining fluxes for the steel industry so that waste disposal from the aluminum industry can be reduced with economical and environmental benefits for both industrial sectors.

关键词： calcium aluminate environmental concern ferronickel hot metal desulphurization

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Inclusion Characterization in High Strength Low Alloy Steel for Pipeline Application

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Journal of Iron and Steel Research International 2011年第S1期18卷 762-768页

作者： Wu Paul mclean Alex Dept.Mat.Sci.& Eng. University of TorontoOntarioCanada M5S 3E4

In this work several methods including sulphur printing,modified spark spectrum analysis and SPEED-SEM-EDX methods were used to study the morphology,composition and distribution of inclusions in pipeline *** procedure for the last-mentioned method includes:metal sample preparation using Selective Potentiostatic Etching by Electrolytic Dissolution (SPEED) together with inclusion observation and detection using SEM-EDX *** results of sulphur printing and spark spectrum analysis showed that there was a well-defined centerline containing relatively high concentrations of sulphur in the steel slab studied in this *** results of SEM study showed that most inclusions found in the steel samples were globular in morphology,and roughly 2-5 micrometers in *** inclusions were rich in sulphur and *** inclusions with a bright globular shape contained Al,Ca,Mn and S,and were likely composed of MnS,CaS and calcium *** was concluded that sulphur printing is a convenient and inexpensive method for inclusion analysis,Spark Spectrum Analysis provides a complete and self-contained technique for inclusion detection,and the SPEED-SEM-EDX procedure is best suited for in-situ and three-dimensional observation of inclusions.

关键词： pipeline steel inclusion detection segregation sulphide continuous casting HIC cracking

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Impact of maternal smoking on the infant gut microbiota and its association with child overweight: a scoping review

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World Journal of Pediatrics 2019年第4期15卷 341-349页

作者： Cara mclean Shelly Jun Anita Kozyrskyj Department of Obstetrics and Gynecology University of AlbertaEdmontonCanada Department of Pediatrics University of Alberta3-527 Edmonton Clinic Health Academy11405-87 AvenueEdmontonAB T6G 1C9Canada School of Public Health University of AlbertaEdmontonCanada

Background Childhood obesity is a growing public health concern with evidence demonstrating that while infant exposure to maternal smoking is linked to low birth weight at birth,there is a rapid catch up in weight and increased risk of obesity in later *** scoping review aims to synthesize up-to-date evidence on the impact of maternal smoking on the infant gut microbiota and its association with child *** We conducted a PRISMA-compliant scoping *** population-based cohort studies published between 1900 and April 2018 were *** publications were retrieved from seven databases:PubMed,Medline,Embase,Scopus,Biosis,Cochrane library,and Web of Science Core *** A total of three prospective cohort studies were included which utilized high-throughput 16S rRNA gene sequencing to assess the gut microbiota and included a total of 1277 infant/neonatal *** exposed to environmental smoke had a higher relative abundance of Ruminococcus and *** exposed to environmental smoke during pregnancy or postnatally were found to have increased gut bacterial richness,particularly Firmicutes at 3 months of age,while 6-month-old infants born to smoking mothers had an increased abundance of Bacteroides and *** Firmicutes richness at 3 months of age was associated with elevated odds of child overweight and obesity at 1 and 3 years of *** The limited evidence to date warrants further large scale,longitudinal studies to explore the impact of maternal smoking and environmental tobacco smoke on the infant gut microbiome and its relation to child overweight.

关键词： Environmental tobacco smoke Gut microbiota Infants Maternal smoking Overweight

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Comparative performances of new and existing indices of crown asymmetry:an evaluation using tall trees of Eucalyptus pilularis(Smith)

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Journal of Forestry Research 2021年第1期32卷 43-65页

作者： Fanlin Kong Huiquan Bi Michael mclean Fengri Li Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education School of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Forest Science NSW Department of Primary IndustriesParramattaNSW 2150Australia School of Ecosystem and Forest Sciences The University of MelbourneParkvilleVIC 3010Australia

Over the past 50 years,crown asymmetry of forest trees has been evaluated through several indices constructed from the perspective of projected crown shape or displacement but often on an ad hoc basis to address specifi c objectives related to tree growth and competition,stand dynamics,stem form,crown structure and treefall *** sharing some similarities,these indices are largely incoherent and non-comparable as they diff er not only in the scale but also in the direction of their values in indicating the degree of crown *** the fi rst attempt at devising normative measures of crown asymmetry,we adopted a relative scale between 0 for perfect symmetry and 1 for extreme *** existing crown asymmetry indices(CAIs)were brought onto this relative scale after necessary modifi *** new CAIs were adapted from measures of circularity for digital images in computer graphics,indices of income inequality in economics,and a bilateral symmetry indicator in plant leaf *** performances of the 13 CAIs were compared over diff erent numbers of measured crown radii for 30 projected crowns of mature Eucalyptus pilularis trees through benchmarking statistics and rank order correlation *** each CAI,the index value based on the full measurement of 36 evenly spaced radii of a projected crown was taken as the true value in the benchmarking *** index(CAI 13)adapted from the simple bilateral symmetry measure proved to be the least biased and most *** performance was closely followed by that of three other *** minimum number of crown radii that is needed to provide at least an indicative measure of crown asymmetry is *** more accurate and consistent measures,at least 6 or 8 crown radii are *** range of variability in crown morphology of the trees under investigation also needs to be taken into *** the CAIs are from projected crown radii,they can be readily extended to individual tree cr

关键词： Projected crown shape Circularity Inequality Bilateral symmetry Rank order Eucalyptus pilularis

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Effect of Carbon Properties on Melting Behavior of Mold Fluxes for Continuous Casting of Steels

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Journal of Iron and Steel Research International 2006年第2期13卷 22-26页

作者： I. D. Sommerville A. mclean Department of Materials Science and Engineering University of Toronto Toronto M5S-3E4 Ontario Canada

During continuous casting of steel, the properties of mold fluxes strongly affect the casting performance, steel quality and environment of casting operation. The high temperature microscopy technique was used to investigate the melting behaviour of mold fluxes, and drip test method was used to determine their melting rate. The results showed that free carbon is a dominant factor in governing the melting behaviour of fluxes, and the melting rate is increased with increasing carbon reactivity and decreasing carbon content.

关键词： continuous casting carbon reactivity mold flux flux melting rate steel

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Water Vapour Solubility in Tundish Slags

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Journal of Iron and Steel Research International 1998年第2期5卷 9-16页

作者： Yang Yindong Daya Z A Sommerville I D mclean A Dept.of Metallurgy and Materials Science University of TorontoOntarioCanada M5S 3E4

In the present work,the solubility of water vapour in tundish slag has been studied in the temperature range from 1 400 C to 1 600 C by a thermogravimetric *** water vapour capacity of the slags was calculated and compared with the data from earlier *** results confirm that the solubility of water vapour in slags increases with increasing water vapour *** relation between the two parameters obeys Sievert’s *** slags with optical basicities from 0.5 to 0.8,a regression equation was obtained to express the relation between the water vapour capacity and optical basicity of slags.A tundish slag system with the desired properties can be designed according to the correlations between the optical basicity and various capacities of slags.

关键词： tundish slag water vapour capacity optical basicity

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