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 タイトルヨミ シラカシ ジュカン ダンメン ノ ヒョウカホウ ニツイテ ダイ1ポウ シュウイ オヨビ チョッケイ ソクテイ ニヨル スイテイ ダンメンセキ ノ ゴサ 日本語以外のタイトル On the Appraisal Methods of Cross-Section of "Shirakashi" (Quercus myrsinaeoflia Blume) Stem(I) : The Error of Estimated Cross-Sectional Area Based on Girth or Various Diameter Measurments ファイル 言語 日本語 著者 安井 鈞 内容記述（抄録等） The author studied on the fittness and the errors among estimated cross-section areas of a tree, calculated by some usual estimation formulae, in which a cross-section figure is assumed as a circle.1 . Samples were 44 disks taken from shoots of Quercus myrsinaefolia of some coppice forests in Shimane Prefecture.2 . Measurements were taken at the height of 0.00 m (section I), 0.73 m (section II), 1.46 m (section III), as follows;i ) Precise cross-section areas, measured by a planimeter.ii) Diameters in 18 directions, every ten degrees, on a disk, so that he could find a maximum and a minimum diametet and a pair of two diameters crossing at right angle.iii) Girths, measured by a tapeline, supplemented by a curvimeter.3 . As a value D in the estimation by a formula ^π_4D^2, he picked up following values,D_1 : a diameter in a random directon.D_2 : the arithmetic mean of a pair of diameter crossing at right angle.D_3 : the geometric mean of a pair of diameter crossing at right angle.D_4 : the mean of the maximum and minimum diameter.D_5 : the mean of a pair of the maximum and a crossing diameter.D_6 : the mean of the minimum and a crossing diameter.To check the fittness of these of estimations, the author carried a regression analysis, and he found,i ) When it is a = 0, b = 1, the fitiest index for the section III and II might be the mean of a pair of the minimum and the crossing diameter.ii) In view of convergency of variances around a regression line, the fittest were the mean of the maximum and the minimum diameter for the section III, and the geometric mean of a pair of diameters crossing at right angle for the section I. 掲載誌名 島根農科大学研究報告 巻 10 開始ページ (A)141 終了ページ 145 ISSN 05598311 発行日 1962-03-31 NCID AN00108241 出版者 島根農科大学 出版者別表記 The Shimane Agricultural College 資料タイプ 紀要論文 部局 生物資源科学部 備考 A,Bを含む