start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=1 article-no= start-page=61 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=1975 dt-pub=19750701 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=ERRATUM en-subtitle= kn-subtitle= en-abstract= kn-abstract= en-copyright= kn-copyright= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=School of Engineering, Okayama University kn-aut-sei=School of Engineering, Okayama University kn-aut-mei= aut-affil-num=1 ORCID= affil-num=1 en-affil= kn-affil= END start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=1 article-no= start-page=49 end-page=59 dt-received= dt-revised= dt-accepted= dt-pub-year=1975 dt-pub=19750701 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=On the Vacancy-Zn Atom Binding Energy in Al en-subtitle= kn-subtitle= en-abstract= kn-abstract=Binding energy between a vacancy and a Zn atom in Al was investigated by measurement of as-quenched resistivity in Al-0.021at % Zn and pure-Al, with the estimation of vacancy loss during quenching. The contribution of clusters to resistivity in Al-0.021at % Zn waa also investigated. Their results are summarized as follows: (1) The results of isothermal and isochronal annealing indicate that clusters in Al-0.021at % Zn cnuld not be detected beyond the experimental errors. (2) The model applied to estimate the vacancy loss in pure-Al has enough validity. The quantitative estimation of clusters ana the improvement in experimental conditions are greatly desired, which enable the more detailed, analysis of the data. en-copyright= kn-copyright= en-aut-name=OhtaMutsuo en-aut-sei=Ohta en-aut-mei=Mutsuo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KawazoeHisami en-aut-sei=Kawazoe en-aut-mei=Hisami kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=SakakibaraAkira en-aut-sei=Sakakibara en-aut-mei=Akira kn-aut-name=榊原精 kn-aut-sei=榊原 kn-aut-mei=精 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Industrial Science affil-num=2 en-affil= kn-affil=Graduate school of Industrial Science affil-num=3 en-affil= kn-affil=Department of Industrial Science END start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=1 article-no= start-page=39 end-page=47 dt-received= dt-revised= dt-accepted= dt-pub-year=1975 dt-pub=19750701 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=G.P.zones and Clusters in Al-Zn Alloy and Al-Cu Alloy en-subtitle= kn-subtitle= en-abstract= kn-abstract=As to Al-Zn alloy, the difference between the formation of G.P.zones and that of clusters was investigated by measurements of electrical resistivity. The results obtained were summarised as follows: (1) G.P.zones formed during the quench and quenched-in vacancies increase greatly as-quenched resistivity P(o) as quenching temperature Tq is raised, and clusters increase slightly P(o) as Tq is lowered. (2) For one Tq and one Ta, the time required to reach P(e)' for Al-1.3at % Zn alloy is longer than that for Al-3.0at % Zn alloy. This is due to the difference of number of zinc atom in the clusters. (3) For one Ta and one concentration of zinc, the time required to reach p'(e) at Tq = 170℃ is longer than that at Tq = 300℃. This is due to the difference in concentration of quenchedin vacancies. As to Al-Cu alloy, the solvus temperature for G.P.zones was determined from the existence of P(m) in ageing curves by measurements of electrical resistivity. Consequently the solvus temperature is between 20℃ and 60℃. en-copyright= kn-copyright= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=OhtaMutsuo kn-aut-sei=Ohta kn-aut-mei=Mutsuo aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=HamamotoTakao kn-aut-sei=Hamamoto kn-aut-mei=Takao aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=Department of Industrial Science affil-num=2 en-affil= kn-affil=Graduate school of Industrial Science END start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=1 article-no= start-page=17 end-page=37 dt-received= dt-revised= dt-accepted= dt-pub-year=1975 dt-pub=19750701 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Computer Program of Forward Selection and Backward Elimination Procedure in Linear Discriminant Analysis and Test forDifferences Between Mean Values of Two Populations en-subtitle= kn-subtitle= en-abstract= kn-abstract=In multivariate analysis, the linear discriminant analysis and the test for differences between mean values of two populations are of wide application. It is not essential to increase the variables only in order to increase the degree of accuracy of discrimination or test without evaluating the effect of variables. Therefore the computer program of selection procedures of variables in these two methods is mentioned in this paper. en-copyright= kn-copyright= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=OsakiHirokazu kn-aut-sei=Osaki kn-aut-mei=Hirokazu aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=KikuchiSusumu kn-aut-sei=Kikuchi kn-aut-mei=Susumu aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=Department of Industrial Science affil-num=2 en-affil= kn-affil=Department of Industrial Science END start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=1 article-no= start-page=1 end-page=16 dt-received= dt-revised= dt-accepted= dt-pub-year=1975 dt-pub=19750701 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Undeformed Chip Shape in Angular Grinding en-subtitle= kn-subtitle= en-abstract= kn-abstract=This paper describes the basic boundary conditions in angular grinding, which is widely applied as a high efficiency machining and where a complicated-shaped workpiece is ground at the same time. The angular grinding is first classified into three basic types, an external, a surface and an internal angular grinding, depending on the axis angle between the wheel and the work axes. The undeformed chip shape, which is characterized by the interference angle, the maximum chip thicknes and the chip length, is then analyzed in each type of angular grinding. The effects of grinding conditions such as the axis angle, the speed ratio, the radius ratio and the successive cutting edge spacing upon the geometry of undeformed chip are discussed to make clear the relations between the basic boundary conditions and the working conditions in angular grinding. en-copyright= kn-copyright= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=NakajimaToshikatsu kn-aut-sei=Nakajima kn-aut-mei=Toshikatsu aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=NakagawaHeisaburo kn-aut-sei=Nakagawa kn-aut-mei=Heisaburo aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=Department of Mechanical Engineering affil-num=2 en-affil= kn-affil=Department of Mechanical Engineering END