A nonlinear FEM is employed to analyze the ultimate behavior of steel octagonal-section columns composed of plate with various width-thickness ratios. From numerical results, equivalent averaged stress-strain relations for steel octagonal-section columns including the effect of local buckling are derived. The equivalent stress-strain relations for cyclic loading are also formulated. By introducing the equivalent stress-strain relations into a frame analysis, a numerical method, which is capable of analyzing ultimate behavior consideration of local buckling, is developed. Accuracy of the proposed method is shown through several numerical examples.

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本論文は, コンクリートを充填した断面鋼製橋脚の耐震設計のための簡易解析法を, 準静的繰り返し載荷実験との比較により検証, 提案したものである. ファイバー要素を用いた骨組解析に, 断面鋼部材に充填されたコンクリートの圧縮実験より定式化された充填コンクリートの応力-ひずみ関係式と, FEMにより求めた外側鋼部材の局部座屈の影響を考慮した応力-ひずみ関係式を導入した. 実験供試体と同一の解析モデルにより, 一定死荷重の下, 降伏変位の整数倍を生じる水平荷重を繰り返し載荷した. 実験および簡易解析による荷重-変位履歴曲線を比較した結果, 簡易解析によって実用的に十分な精度で実験現象を追従できることを明らかにした.

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都市高速など市街地における高架橋は, 立地的な条件から様々な構造形態の橋脚が使用されている. なかでも逆L形鋼製橋脚のような上部工重量が偏心載荷される橋脚はT形鋼製橋脚に比べ, 偏心による付加曲げが作用するため, 地震後の残留変位が張出し方向に大きく生じることが予想される. このため橋脚の機能保持の観点からこの影響を検討しておくことは重要である. 本研究では, 鉛直荷重が偏心して作用した鋼製橋脚について等荷重繰返し載荷実験および, 汎用構造解析プログラムDLANAによる弾塑性有限変位解析を行い, 偏心パラメータe/r (e=偏心量, r=橋脚の断面2次半径) が強度や変形性能に及ぼす影響を検証した.

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左右15。に呈示された幾何学図形 (円・四角形・) 追視時のサッケイド関連電位を検討した.大学生8名を対象に頭皮上8部位から脳波を導出した.中央の凝視点が消えると同時に呈示された図形追視条件 (NON-TARGET条件) と, 呈示図形が円の場合にボタン押しをする条件 (TARGET条件) についてサッケイド終了時点にあわせて加算波形を求めた.ラムダ反応はいずれの条件でも左後頭部よりも右後頭部で振幅が大きかった.TARGET条件では, 円と弁別時に200ms前後に陰性成分の出現が認められた.また, 300ms以降に陽性成分の出現が認められ, 四角形よりも弁別の難易度が高いでその潜時は延長していた.これらの結果から図形弁別の過程がサッケイド関連電位に反映されていることが示唆された.

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 A square hollow section member is generally used as a column in steel structures. Local buckling is known to affect the large deformation behavior. Local buckling is more likely to occur when the width-thickness ratio of the plate elements is large. Therefore, an octagonal cross sectional member that can reduce the width-thickness ratio of the plate elements and reduce the material is expected to be column.

 Although there have been many previous studies on octagonal cross sectional members, none have examined the inelastic behavior of octagonal cross sectional members subjected to shear bending. In this study, the plastic deformation capacity of an octagonal cross sectional member subjected to shear bending is clarified based on the actual behavior of the member, and an evaluation method is proposed.

 In this study, the buckling coefficient of an octagonal cross sectional member under compression or bending is calculated by eigenvalue analysis using the finite element method, and a buckling coefficient evaluation formula for octagonal cross sectional members under compression or bending is proposed.

 In addition, the plastic deformation capacity of the octagonal cross sectional members was confirmed by the large deformation analysis of the cantilevered column form under axial and bending shear forces for the octagonal cross sectional members. In the comparison, the effect of the length of both members on the large deformation behavior was studied, and the plastic deformation capacity was investigated using a square hollow section member with the same thickness-width ratio of the plates. Next, in order to investigate the effect of the maximum value of initial imperfections on the plastic deformation capacity, a large deformation analysis is performed using the maximum value of initial imperfections as a parameter.

 In order to understand the actual behavior of the octagonal cross section members, the plastic deformation capacity of the octagonal cross section members was confirmed by cantilevered bending shear tests and compared with the plastic deformation capacity of the square cross section members with equal width and length.

 The buckling coefficient evaluation formula for octagonal cross section members obtained in this study is applied to the new width-thickness ratio for square cross-section members proposed in Reference 2), and the plastic deformation capacity evaluation formula using the new width-thickness ratio for square cross section members proposed in this study is examined whether it is possible to evaluate the plastic deformation performance of octagonal cross section members obtained by large deformation analysis and loading tests. The effect of the initial imperfection on the plastic deformation capacity of the square and octagonal cross section members is taken into account.

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The research of a way to plan Tahoutou pagoda was paid attention for reasons of remains and Japanese traditional architectural reference books. Dr. Hamazima pointed out the way that diameter of the upper story was utilized in “Siwari-sei” theory of over all clumn spacing of the lower story. It was so interesting and I felt his point have ring of truth, because of my verification. However, the early Isiyamadera tahoutou pagoda and Kongouzanmaiin tahoutou pagoda made use of other technique, so I couldn't suppose that diameter of the upper story was decided with “kansu-sei” theory and “Siwari-sei” theory. Therefore I verified the technique a regular octagon was used as underlay in Tahoutou pagoda of mediaeval period, because I noticed to diameter of the upper story used twelve column of circle.

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正加工物の一つの角を取り出して,加工物が正から円になってゆく過程を立体的に示したのが図10である.図10は研削速度が1880m/min,切込み速度が10μm/sec,コンタクトホイルの硬度がDro 40で研削した加工物を形状測定装置で研削時間30秒ごとに測定した結果である.円孤の部分が研削面であり,研削時間の経過とともに円孤が長くなることから研削時間の経過とともに研削面が長くなり,研削時間が300秒になると加工物の全周面が研削されることがわかる.図7,図8に示された実測による研削時間と研削深さ,単位時間当りの研削深さとの関係は図3,図4に示された理論計算から求められた研削時間と研削深さ,単位時間当りの研削深さとの関係とよく一致している.研削速度を1880m/min,切込み速度を5μm/secとして研削加工を行なった実験値による研削時間と単位時間当りの研削深さとの関係を示した図8の曲線からKの値を求めると,Dro 40とDro 80のコンタクトホイルを使用した場合にはKの値が0.04～0.05の範囲にあると考えられる.また,コンタクトホイルの硬いものを使用して研削した場合にKの値が大きくなる.このKの値は円筒形加工物を円筒研削した場合とほぼ同じである.このことから,取りしろが変動する加工物も取りしろの変動がない円筒形加工物と同じように円筒研削ができ,円筒形加工物を円筒研削したときに求められるKの値を用いて,正加工物が円筒研削されて円形になる過程を理論計算することができた.そこで正加工物が円形になるサイクルタイムを理論計算から求めた.
加工物の最後に研削される部分(図1のB点)における単位時間当りの研削深さについて考えると,(10)式でθ=0とおけば,v_e=v_s[1-exp{-K(t-R₀/v_s×0.0761)}](13)となる.これを一次おくれの要素とみなして,正加工物が円形になるサイクルタイムを時定数の考え方で表わす.
Tを時定数とし,(13)式でv_e=0.63v_s,t=Tとすると,
T=0.994/K+0.0761×R₀/v_sとなる.
(14)式においてv_s=5,10,20,40μm/secとして係数Kと時定数丁との関係を示したのが図11である.図11より切込み速度が増すとサイクルタイムは短かくなり,特に切込み速度が5～10μm/secと比較的低速度のときにその効果は大きく現われる.今回の実験範囲はv_s=5,10μm/sec,K=0.04～0.05であり,この範囲ではコンタクトホイルの硬さがサイクルタイムに及ぼす影響がほとんど見られない.
また,回式の0.0761×R₀は加工物の形状によって決まる値で山の高さを表わしており,加工物が正以外の形状であるときにも加工物の山の高さを知ることができれば,(14)式により作業のサイクルタイムが計算できる.
なお,理論計算と実験結果をまとめるとっぎのようになる.
(1)取りしろが変動する加工物を研削するときも,円形加工物を研削するときと同じように研削でき,工具と加工物との問に飛び跳ねなどの現象が見られない.
(2)本研究でたてた理論式によって計算した結果と実験結果とがよく一致しており,この実験では砥粒先端角,被削材の降伏応力などによって決まる係数K_Gとコンタクトホイルのばね定数K_wとの積である係数Kが0.04～0.05の範囲にあった.これは円筒形加工物を研摩ベルトによって円筒研削したときの値とほぼ等しくなった.また理論式により作業のサイクルタイムが計算できた.

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This study is about the octagonal building of GYEONGJU NAJONG, the remains of a ritual facility of ancient Shilla Dynasty. The purpose of this study is to examine the column arrangement of the octagonal building, and reveal the determinant factors for column arrangement by reviewing the sequential processes in building the facility.
The results are as follows : the octagonal building was designed with special structure that internal structure is rotated against external column arrangement. Difference in the number of columns between inside and outside was caused by restrictions on the scale of the inner and outer circumference. And it induced rotation of the internal structure for the external column array. The circumference of internal and external column of the octagonal building was defined to include the core portion of predecessor facility, consisting of the central pit and the six pits.

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 Cold-formed steel members are widely applied in columns and other axial members in steel structures. One of the key issues in design of cold formed steel is local buckling strength under axial compression. As a means to avoid premature local buckling, we have paid on attention to the application of octagonal section members. The local buckling behavior of octagonal section members have been investigated by many researchers. However, these studies have focused mainly on regular octagonal sections and do not considered the restraining effect between adjacent plate elements. In this paper, we conducted numerical analysis (Finite Strip Analysis and Finite Element Analysis) and stab column tests, to investigate the elastic buckling strength and post buckling strength of octagonal section members where the adjacent plate elements have different width-thickness ratios.
 First, we conducted Finite Strip Analysis to investigate the elastic buckling strength of octagonal section members. Through these numerical analysis, it was found that the octagonal section members generally showed higher strength than that of simply supported plate. These strength increases were depended on the difference of the width-thickness ratio between adjacent plate elements and the change of buckling mode.
 Second, we examined the post buckling strength of octagonal section members through a stab-column compression test. We compared the post buckling strength of square section and that of octagonal section, and found that the post buckling strengths of octagonal section members was higher than those of square section members, when they have a same diameter. In addition, it was known that the post buckling strength of octagonal section members could be evaluated by the traditional effective-width method, where simply supported conditions were assumed.
 Finally, we investigated the post buckling strength of each plate elements of octagonal section members whose adjacent plate elements have different widths by Finite Element Analysis. The post buckling strength of the plate elements with a large width was higher than of square section member. On the other hand, the post buckling strength of the plate elements with a small width was lower than that of square section member. These increase and decrease were dependent on the restraining effect between adjacent plate elements. Because of this trade-off effect between the adjacent plate elements, the effective width method, which regarded each plate elements as a simply supported plate, gave a good estimation about post buckling strength of the octagonal section members.

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This paper is the pursuit of "THE KIWARI SYSTEM OF JUHO KIWARI NOTE". In this paper, we introduce the words, "kozukuri", "kikudaki" and "kinosei" as medieval words, which mean "kiwari" Japanese traditional modular coordination. Simultaneously, we examine the definition and the historical background of "daimen" and "komen" as modules in the medieval "kiwari" system found in "Juho Kiwari Note". As a result, we draw out the following conclusion ; the "daimen" module equals one side of the octagonal base of a prismatic pillar, on the other hand, the "komen" module is a 45 orthogonal projection of "daimen" (komen=daimen×√<2>/2). In our opinion, this concept of modules is thought to come from using octagonal pillars, in the case of cylindric pillars, the "daimen" reveals the square based prism of the timber plank used for making the pillar since ancient times. For survey on later periods, we do not identify "daimen" and "komen" modules, however, we mention the appearance of a new module named "men" specially for residences in the Azuch Momoyama period, generating the gradual disappearance of the "daimen" and komen" proportion in "kiwari" system.

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嗄声を有する各種喉頭疾患について, 持続発声時の平均呼気流率 (DC) とAC/DC% (声の能率, 一色) の2のパラメーターを測定し, 疾患別に比較検討した.
声帯麻痺例ではDCとAC/DC%の間には逆の相関があるが, 喉頭炎や sulcus vocalis ではAC/DC%が低くてもDCは正常範囲にとどまる. 前者は声門閉鎖不全が後者は声帯の物性の変化が嗄声の主因と考えられるが, この違いが2つのパラメーターの上に反映されたものと考えられる.

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The ventilation efficiency by the pressure difference of tower inside and outside, which is generated by wake formed in the leeward side of the tower or by the Venturi effect, was researched by a wind tunnel experiment and a numerical simulation. The ventilation efficiency by wake increased with the increase of wind speed, but was unrelated to the number of open windows. The ventilation efficiency by the Venturi effect increased with the increase of wind speed and of Venturi width. The numerical simulation reproduced the ventilation efficiency of the wind tunnel experiment.

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In the Bapitistery of Parma (1196-1216, Emilia, Italy), renowned for the magnific plastic decoration realized by Benedette Antelami School, there are two baptismal fonts. One is a large octagonal font situated in the center, and the another is small circular font placed in the south east nich. The period of their construction, as well as which of the two fonts was at the same time as the Baptistery, has not yet been made clear. On this respect, the author examines a document dated 1225, kept in the Parma Cathedral Chapter Archives. The document, reference to a little part of which is made in sources belonging to the middle of XIXth century, descrives the scenes of baptism represented in the two fonts as corresponding to the way in which baptism was held between the end of XIIth century and the beginning of XIIIth century. From a close investigation of the document, it has turned out that the large octagonal font is coeval to the Baptistery, whereas the small circular font was realized for the Cathedral of Parma, before the construction of the Baptistery. The author futhermore exmines the simbolical meaning of the octagonal form of one of the fonts. This meaming, handed down from the Early Christian period, is to be interpretated within the context of Italian Medieval City-State.

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