大気中超微小粒子の粒子組成ならびにその動態に関する研究

学位記号番号 : 博理工甲第874号博士の専攻分野の名称 : 博士(工学) 学位授与年月日 : 平成24年3月22日textapplication/pdfthesi

ヨウダとソウダの主観性

2000-10-31departmental bulletin pape

Estimation of Cable Tensions of Cable-stayed Bridge using Vibration Method and PSO

In the maintenance and management of the cable-stayed bridges, it is important to measure the cable tension and to maintain the cable tensions within permissible errors for the designed cable tensions. In this study, a reliable method to estimate the cable tensions of cable-stayed bridge is proposed by using the natural frequency and PSO. The natural frequency is measured by the vibration method. The cable tensions are identified by using the least-square method and PSO. The effectiveness and usefulness are illustrated by applying the method to the Bandai bridge (PC pedestrian cable-stayed bridge) in Echizen city.departmental bulletin pape

Changes of management system in Utsunomiya University Forests -Comparison of the 50th and 80th anniversary-

text紀要論文 / Departmental Bulletin Paperdepartmental bulletin pape

Screw retraction behavior during plasticization process in injection molding

熱可塑性樹脂を成形する方法として，射出成形は最も一般的な方法である．しかし，射出成形では様々な成形不良が発生する．その原因は，可塑化された樹脂の溶融状態に影響されると考えられる．さらに，その溶融状態は可塑化工程におけるスクリュの挙動に影響されると考えられる．そこで，射出成形における可塑化工程でのスクリュ後退速度を調査し，樹脂溶融体の安定性を把握することとした．本研究では，射出成形における回転速度，背圧，加熱シリンダの温度の条件がスクリュ後退速度に与える影響を明らかにした．実験結果から，スクリュ後退速度は，樹脂の溶融安定性に影響されると考えられた．また，実験条件とスクリュ後退速度の関係を明らかにした．Injection molding is the most common method of molding thermoplastic resins. However, various defects were occurred in injection molding. It is considered that the cause of defects was influenced by the melt state of plasticized resin. Furthermore, it is considered that the melt state was influenced by the behavior of screw in the plasticization process. Therefore, the screw retracting speeds during the plasticization process in injection molding was investigated to understand the stability of the resin melt. In this study, the influence of the condition of rotational speed, back pressure and heat in the injection molding on the screw retracting speed was clarified. From experimental results, it was thought that the screw retracting speed was affected by the melt stability of the resin. In addition, the relationship between experimental conditions and screw retracting speed was clarified.application/pdfdepartmental bulletin pape

Study on the hardness of curved rebar by a simple bending machine

異形棒鋼は用途に応じて曲げ加工されて利用される．異形棒鋼の曲げられた部分の材料特性は加工硬化により変化する．土木工事などでは，曲げられた部分をさらに曲げ加工することがあるため，材料特性の変化を把握することは重要である．本研究の目的は，加工による材料特性の変化を把握する第一歩として，曲げ加工後の異形棒鋼の硬さ分布を明らかにすることである．本研究では，3種類の回転角度で加工した異形棒鋼を4つの領域に分けて硬さ試験を行った．支点ローラに押し付けられて曲げられる領域は，回転角度が増加しても硬さはあまり変化しない．棒鋼受けと支点ローラの間ならびに支点ローラと力点ローラの間の領域は，支点ローラに近いほど硬さの測定値が大きい．Rebars are used by bending according to the purpose. The material properties of bent portion of rebars change due to work hardening. In civil engineering work, it is important to understand the changes in material properties because bent portion are sometimes further bent. The purpose of this research was to clarify the hardness distribution of a rebar after bending as a first step in understanding the changes in material properties due to processing. In this research, rebars bent at three different rotation angles were divided into four areas for hardness test. The area that is pressed against the fulcrum roller and bent does not change much in hardness as the rotation angle increases. In the area between the rebar receiver and the fulcrum roller and between the fulcrum roller and the circular roller, the closer to the fulcrum roller, the greater the hardness measurement.application/pdfdepartmental bulletin pape

Study of time-dependent CP-violating asymmetries in b→sq̅q decays

journal articl

高酸素吸入や高気圧環境が身体に及ぼす影響 : 酸素動態、酸化ストレスの面から

application/pdf三重大学大学院教育学研究科博士前期課程教科教育専攻保健体育専修208thesi

Study on a new semi-solid injection molding method for heat-resistant magnesium alloys : trial production and process verification of machine

以前に報告した型締め力20トンの半凝固射出成形機の実験結果に基づき,型締め力200トンの試作機が設計され,製造されました.この試作機の使用によって,半凝固温度領域の制御方法の精度が確認されました.また,固相率が30%であっても製造できることが検証されました.同じ成形条件による試行テストの結果,溶融状態および半凝固の状態によって流動性が異なることを明らかにしました.また,この新しい半凝固射出成形を従来のダイカストと比較することによって,多くの長所があることが検証されました.この新しいプロセスの実用性を確認するために,自動車の主要部分であるクラッチピストンを試作成形することが行なわれました.欠陥のないクラッチピストンを得るために実験計画法が利用されました.耐久性は,欠陥のないクラッチピストンに繰返し荷重を作用させる装置を製作し,それを使用して評価されました.その結果,試作品は従来のアルミニウム合金から作られた部品より劣っていました.この問題を克服するためには,アルミニウム合金と比較して低剛性であるマグネシウム合金に適した部品形状の設計をする必要があることが判明しました.Based on the experiment result of semi-solid injection molding machine which has the mold clamp force of 20 ton[f] reported previously, the trial model with the mold clamp force of 200 ton[f] was designed and then was manufactured. By using this trial model, the accuracy of the control method of semi-solid temperature zone was verified, and it was checked that a solid phase rate could fabricate at least 30%. As the result of the trial test by same molding conditions, it was clarified that mobility differed by the molten state and the semi-solid one. And it was checked that there were many merits by comparing this new semi-solid injection molding process with the conventional die casting. In order to verify this new process, trial production molding of the clutch piston which was a main part of a car was carried out. At this time, in order to obtain the clutch piston without defect, an experimental design was used. Durability was evaluated using the equipment which allowed repeated load on a clutch piston without a defect. As a result, trial production parts were inferior to the conventional parts made from aluminum alloy. In order to conquer this problem, it turned out that the part shape which was suitable for the Magnesium alloy of low rigidity compared with the aluminum alloy needs to be designed.抄録に表記の[f]は上つき文字application/pdfdepartmental bulletin pape

Study of the fracture limit evaluation method from the edge of steel sheet on the car crash (second report)

自動車車体衝突時には,鋼板製の部品のエッジを起点にして破断が発生する場合がある.また鋼板エッジの破断限界はエッジの加工条件によって大きく変化することが知られている.本報では,Bピラーを模した穴付ハット型試験体の3点曲げ試験とそれらのFEM解析を行った.結果として,第1報で提示した穴付き小型引張試験片による実験結果に基づく評価式によって,ハット型部材の破断破断伸びを予測することができた.またこれらの破断限界に及ぼす衝突速度の影響についても考察を行った.In the vehicle collisions, fractures can be occurred from the edge of steel sheet parts. And it is known that the fracture limit on the edge of steel sheet is much affected by the edge processing conditions. In this report, 3 points bending tests and their FEM simulations of hat channel specimens with hole which modeled for B-pillar were conducted. As the results, the fracture elongation of the hat channels can be predicted by correlation equation studied by the small tensile specimen with hole in the first report. And the effects of crash speed on the fracture limit were also studied.application/pdfdepartmental bulletin pape