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    On a Descriptive Study of a Word-stress System : From a Fieldworker\u27s Point of View

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    There have been much scholarly work on word-stress systems around the world, and many theoretical issues seem to have been solved. However, several questions will still soon arise once you conduct field researches on a stress accent language: How do we verify it\u27s accent system as word-stress system? What prosodic features does a stress accent language has to have? Is it always straightforward to elicit wordstress patterns in research interviews? Is a stress accent language which has another prosodically distinctive feature still diagnosed as a stress accent language? In the present paper, the author, who has been involved with descriptive investigation into the word-stress systems of the North Germanic languages, attempts to resolve these questions based on his experience and knowledge acquired through descriptive field researches.å­Šè¡“è«–

    The Effect of Covid-19 pandemic in the aspects of Disaster Stress : Compare with the effect of 2018 Iburi East Area Earthquake

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    After Covid-19 pandemic , a questionnaire was conducted on the psychophysiological situation and the implementation level of preventive method and stress level toward the student who affected by Iburi East Earthquake. It is indicated that the effect of psychophysiological situation is almost same level with immediately after earthquake and prevention method,especially mask and behavior restriction, are serious stressor. Covid-19 pandemic strikes people multiple stress as disaster stress.å­Šè¡“è«–


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    垌土類硫化物α-R2S3R = La-Dy、PmずEuを陀くは、空間矀Pnmaの盎方晶結晶構造を有し、2぀の独立した垌土類サむトR1, R2を持っおいる。この䞀連のα-R2S3では、ほが党おの化合物が1぀たたは2぀の連続した反匷磁性転移を瀺す。しかし、α-Sm2S3のみは10 K以䞋の䜎枩で連続した匱匷磁性(WFM)転移を瀺し、その磁化の特城的な振る舞いは十分に解明されおいない。α-Sm2S3の抵抗率は高枩偎転移枩床の盎䞊で巚倧な増倧ず回埩を瀺し、この100倍を超える異垞な増倧は非垞に魅力的である。たたac面内における磁化容易軞に関する奇劙な亀錯が芳察されおきた。α-Sm2S3の特城的な磁気転移ず新奇な茞送特性の機構を明らかにするために、単結晶ず焌結䜓詊料を甚いお䜎枩物性を枬定した。気盞化孊茞送法により、b軞方向に長くお6぀の偎面を持぀針状単結晶が育成された。枬定に甚いた党詊料は、たずえ11個の偎面を持぀ものであっおも、X線回折の手法により双晶ではなく単結晶であるこずが確認された。11偎面を持぀詊料の磁化は通垞の 6 偎面の詊料ず本質的に同じであった。たた、磁化容易軞がa軞ずc軞の䞡方の詊料が存圚するこずが本研究においおも確認された。逐次的なWFM転移を確認し、Curie枩床をTC13.6 KずTC21.8 Kず決定した。匱匷磁性転移埌の磁堎䞭冷华(FC)過皋における磁化は、磁化容易方向であっおもSm3+の飜和理論倀の1/18ず小さく、困難方向ではさらに小さい。この特城的なWFM 特性は、b軞方向に反匷磁性的に秩序化したSm3+の磁気モヌメントが傟くこずによっお生じる正味の匷磁性的寄䞎によるものであるず考えられる。単結晶の零磁堎冷华(ZFC)磁化のTC1盎䞊のピヌクは磁区の圢成によっお起こり、焌結詊料のFC/ZFC磁化の同様のピヌクは正味の匷磁性成分の匷い異方性に起因するず結論した。磁気比熱ず磁気゚ントロピヌの解析から、各転移枩床においお䞀぀のSmサむトのみの磁気モヌメントが秩序化し、その基底状態はSm3+クラマヌス二重項であるず結論された。磁気゚ントロピヌは磁堎方向に察しお極めお異方的であり、その倀は小さいが、磁堎方向の違いによっお異なる磁気熱効果が期埅できる。本研究においおは、TC1盎䞊の狭い枩床範囲における電気抵抗率ρの異垞な増倧は、磁化容易軞の異なる䞡単結晶ずもに5桁以䞊に達した。䞡単結晶においお、磁堎印加によりその巚倧な増倧は急速に抑制されるが、無磁堎䞋のρ(T)曲線ず磁堎による抑制のされ方は磁化容易軞によっお異なる特性を瀺す。このTC1盎䞊の珟象は、Sm3+モヌメントの短距離秩序の圢成ず正味匷磁性成分の磁区圢成に起因し、たた耇数の磁化容易軞の存圚ずも密接に関連しおいるず考えられる。磁化容易軞の詊料䟝存性は、Sm3+の基底状態の電荷分垃に耇数の準安定状態が存圚するこずに起因するず考えられる。Rare earth sesquisulfides α-R2S3 (R = La-Dy, except Pm and Eu) possess an orthorhombic crystal structure with the space group Pnma, which has two inequivalent rare earth sites R1 and R2. In this series of α-R2S3, almost all compounds exhibit one or two successive antiferromagnetic transitions. However, only α-Sm2S3 shows successive weak-ferromagnetic (WFM) transitions at low temperatures below 10 K, and the characteristic behavior of the magnetization has not been fully elucidated. In addition, the resistivity of α-Sm2S3 shows an enormous enhancement and restoration just above higher transition temperature and this anomalous enhancement by a factor of more than 100 is very attractive. Additionally, a strange crossing with respect to the easy-magnetization axis in the ac-plane had been observed. To clarify the mechanism of the characteristic magnetic transitions and the novel transport properties in α-Sm2S3, low-temperature physical properties were investigated using single crystal and sintered samples.Needle-like single crystals having the longer direction along the b-axis and 6 side planes were grown by a chemical vapor transport method. All samples used for measurements, even it has 11 side planes, were confirmed by an XRD method to be single crystals but not twins. The magnetization of 11-planes sample was the same essentially as that of the normal 6-planes samples. In addition, the existence of both samples with a and c easy axes of magnetization was confirmed in this study as well. The successive WFM transitions were confirmed and the Curie temperatures are determined as TC1 = 3.6 K and TC2 = 1.8 K. The magnetization value in field cooling (FC) process after the weak ferromagnetic transitions is as small as 1/18 of the theoretical saturation value of Sm3+ even in the easy direction, and much smaller in the hard direction. The characteristic WFM properties are considered to be due to the net ferromagnetic contribution resulting from the canting of the antiferromagnetically ordered Sm3+ magnetic moment along the b-axis. It was concluded that the peak just above TC1 in the zero-field cooling (ZFC) magnetization of single crystals arises from the formation of magnetic domains, while a similar peak in the FC/ZFC magnetization of the sintered sample is due to the strong anisotropy of the net ferromagnetic component.From the analysis of the magnetic specific heat and entropy, it was concluded that the magnetic moments on only one Sm site is ordered at each transition temperature, and its ground state is a Sm3+ Kramers doublet. The magnetic entropy is extremely anisotropic with respect to the magnetic field direction, and although the values are small, different magneto-thermal effects can be expected for different magnetic field directions. The anomalous enhancement of electrical resistivity in the narrow temperature range just above TC1 in this study reached more than five orders of magnitude for both single crystals with different easy magnetization axis. In both single crystals, the huge enhancement is rapidly suppressed by the application of a magnetic field, but the ρ(T) curves under no magnetic field and the way of suppression by magnetic fields show different characteristics depending on the easy magnetization axis. This phenomenon just above TC1 is considered to be caused by the formation of short-range order of Sm3+ moments and the formation of magnetic domains of the net ferromagnetic component, and also be closely related to the existence of multiple easy-magnetization axis. The sample dependence of the easy magnetization axis is considered to be due to the existence of multiple metastable states in the ground-state charge distribution of Sm3+.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊


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    ゚ンドミル加工における切削熱による工䜜物の倉圢は、加工粟床に倧きな圱響を䞎えたす。工䜜物の倉圢を加工䞭に盎接枬定するこずは、加工プロセスの倖乱のために困難です。䞀方、工䜜物の局所的な枩床は、䞀般的な枬定方法で簡単か぀正確に枬定できたす。この研究の目的は、工䜜物の倉圢を監芖する方法を開発するこずです。少量生産における工䜜物の熱状態を掚定するために、局所枩床枬定ず熱シミュレヌションを組み合わせたセンサヌ配眮型熱シミュレヌションが提案されおいたす。本研究では、蚈算時間を短瞮するために、枬定された枩床から工䜜物の倉圢を掚定する経隓的モデリング手法を導入したす。信頌性の高い掚定のためには、適切な枬定ポむントを遞択するこずが䞍可欠です。さたざたな機械加工状況における熱倉圢ず枬定点の枩床ずの関係を確立するために、統蚈情報に基づく蚈枬点遞択方法を倚重線圢回垰 (MLR) 法を䜿甚しお提案したす。゚ンドミル加工プロセスの FEM ベヌスの熱倉圢シミュレヌションを䜿甚するこずにより、加工点で予枬される倉圢の時系列情報を出力倉数ずし、枬定点の枩床の時系列情報を入力倉数ずするこずが可胜になりたす。赀池情報量基準AICを評䟡するこずで独立な枬定点数を決定し、p倀指数を甚いお有効な枬定点を遞択したす。提案された䜓系的な構築方法は、シミュレヌションベヌスのケヌススタディによっお評䟡されたす。FEM シミュレヌションによっお蚈算された倉圢ず工䜜物の倉圢甚に構築された統蚈ベヌスのモデルはよく䞀臎したす。構築したモデルは、最小限の枬定点数で工䜜物の倉圢を衚珟できたす。゚ンドミル加工プロセス䞭のさたざたな境界条件での提案された統蚈モデルの粟床に぀いお議論した埌、修正係数統蚈モデル (MCSM) ず調敎統蚈モデル (ASM) ずいう 2぀の修正統蚈モデルが、関係をより適切に衚珟するために提案されたした。2぀の修正統蚈モデルの誀差分析をそれぞれ議論たした。その結果、MCSM ず ASM はどちらも、枬定点の枩床ずさたざたな境界条件での加工点での熱倉圢ずの関係をより正確に蚘述できるこずが明らかになりたした。The thermal workpiece’s deformation in end-milling process has significant effect on accuracy of machining. In-process direct measurement of workpiece deformation is difficult because of machining process disturbance. On the other hand, local temperatures of workpiece can be easily and accurately measured by common measuring methods. The objective of this research is to develop a method to monitor the workpiece’s deformations. In order to estimate workpiece’s thermal states in small-lot production, a sensor-configured thermal simulation has been proposed by combining local temperature measurements and thermal simulation. To accelerate the process time, an empirical modeling method to estimate workpiece’s deformation from measured temperatures is introduced. It is indispensable to select appropriate measuring points for reliable estimation. In order to establish a relationship between thermal deformation and temperatures of measuring points in various machining situation, a statistic-based selection method is proposed by using the Multiple Linear Regression (MLR) method. By using FEM-based thermal simulation during end-milling process, predicted time-series of deformation at the machining point are regarded as output variable while time-series of temperature of measuring points are regarded as input variables. The similarity of measuring points is evaluated by using Akaike\u27s Information Criterion (AIC), and effective measuring points are selected by using p-value index. Proposed systematic construction method is evaluated by simulation-based case studies. A constructed temperature-based model for workpiece’s deformation shows good agreement to the deformation calculated by the FEM simulation. The constructed model can represent workpiece’s deformation with the minimum number of measuring points. After discussing the accuracy of proposed statistic model in various boundary conditions which correspond to various end-milling situation, two modified statistic model, such as modified coefficient statistic model (MCSM) and the adjusted statistic-model (ASM), were proposed to achieve more suitable expression of the relationship between monitoring points temperature and thermal deformation at machining point of workpiece surface. The error analysis of two modified statistic model were respectively discussed. Consequently, MCSM and ASM are both more accuracy to describe the relationship between temperature of monitoring points and thermal deformation at machining point in various boundary condition.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊圓アむテムは芁旚のみの公開になっおいたす(2024-03-23


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    䞀般的に、構造物に生じおいる劣化原因を䞀぀に特定できない、すなわち耇合劣化ず呌ばれる劣化珟象が倚くみられるようになっおいる。この堎合では各劣化珟象の盞互䜜甚によっお、発生した劣化圢態が耇雑で、単䞀の劣化モデルを足し合わせおその耇雑劣化評䟡を行うこずができない。䞀方、環境負荷䜎枛の芳点からセメント生産時に発生するCO2の削枛や産業副産物の有効利甚が求められ、セメント由来のCO2を削枛するこずができる高炉BFSセメントおよびフラむアッシュFAセメントの研究が進められおきた。この背景ずしお、寒冷地においお、凍害が特色で、BFSやFAを甚いたコンクリヌトの凍害の耇合劣化に察する関心が高たり぀぀あり、怜蚎する必芁がある。凍害ず塩害の耇合劣化に぀いおは倚くの既埀研究があるが、䞭性化ず凍害やアルカリ骚材反応ASRず凍害の耇合劣化に関する報告は少ない。ここで、本研究では、BFSやFAを甚いたコンクリヌトの性化ず凍害や凍害ずASRの耇合劣化の劣化機構を把握しおいく。1. NonAEでは、䞭性化により、OPCず䜎眮換率のBFSコンクリヌトの耐凍害性が䜎䞋しおいるが、高眮換率のBFS簿耐凍害性が向䞊しおいる。BFSの添加により、Non-AEコンクリヌトで、䞭性化埌の耐凍害性は䜎䞋しおいるが、AEコンクリヌトで、䞭性化埌の耐凍害性は䜎䞋しおいない。2 FAコンクリヌトに぀いお、䞭性化による耐凍害性が倉化しおいない。吞氎率に比べ、コンクリヌトの耐凍害性やスケヌリングが现孔構造ずのの関係は認められる。FAの添加により、Non-AEコンクリヌトで、䞭性化埌の耐凍害性は䜎䞋しおいるが、AEコンクリヌトで、䞭性化埌の耐凍害性は䜎䞋しおいない。3OPCコンクリヌトでは、先行のASRにより、凍害を促進したが、先行の凍害により、ASRによる膚匵を促進抑制された。BFSやFAコンクリヌトで、凍害に関わらず、ASRの膚匵を倧幅に枛らされた。BFSやFAの混入により、ASRを抑制するこずで、ひび割れの発生も少なく、ASR埌の耐凍害性を向䞊したこずが確認できた。実環境䞋で、JIS芏栌により、AEコンクリヌトの䜿甚は普通ずしおいる。CO2の削枛するために、環境負荷䜎枛リサむクル材ずするBFSやFAの掚進するずずもに、コンクリヌトの長期匷床など改善されられる。䞀方、BFSやFAの䜿甚は塩害や䞭性化したコンクリヌトの耐凍害性を倉化しおいなくお、さらにASRを受けたコンクリヌトの耐凍害性を向䞊できる。耇合劣化の芳点から、建築分野で、BFSやFAの䜿甚を広く普及するこずを提案した。For concrete structures in cold regions, the frost damage often occurs in the winter construction of concrete, which seriously threatens the performance and structural safety of concrete. The other concrete deteriorations such as salt damage, carbonation, and alkali-silica reaction (ASR) are also related closely to the durability of concrete. So far, the single deterioration mechanism is mainly studied in almost previous studies and the results have been accumulated substantially. However, for the actual concrete structures, it is not possible to suffer a single deterioration only. On the hand, in recent years, in the trend of CO2 emission reduction, blast furnace slag (BFS) and fly ash (FA) are used more widely to reduce the cement consumption in the field of building materials.Therefore, this study will investigate the combined deterioration between carbonation and frost damage, and ASR and frost damage of concrete containing BFS and FA, the effect on the combined deterioration would be also made clear.1. For Non-AE BFS concrete, carbonation can reduce the frost resistance of OPC concrete and BFS concrete with a low replacement ratio but can improve the frost resistance of BFS concrete with a high replacement ratio. For AE BFS concrete, the frost and scaling resistance of all concrete is kept at a high level. The additive of BFS can reduce the frost resistance of Non-AE concrete subjected to carbonation, and has no effect on frost resistance of AE concrete.2. For FA concrete, carbonation has little effect on the frost resistance of concrete. Besides, the frost and scaling resistance are far more reliant on the changes in pore structure than they are on the water absorption. Due to additive of FA, the frost and scaling resistance of AE concrete subjected to carbonation is kept at a high level; while, for Non-AE concrete subjected to carbonation, the frost and scaling resistance tends to decrease.3. for OPC concrete, expansion due to ASR could be restrained when subjected to freeze-thaw, and frost resistance is reduced when subjected to ASR. For BFS and FA concrete, expansion due to ASR could be restrained regardless of being subjected to frost damage. The additive of BFS and FA can improve the frost resistance of concrete subjected to ASR. In real environment, AE concrete is used wildly for concrete construction. Therefore, in the study, it can be obtained that the use of BFS and FA don’t reduce of frost resistance of concrete subjected to salt damage and carbonation and increase the frost resistance of concrete subjected to ASR. Overall evaluation, the use of BFS and FA are beneficial to the safety of concrete.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊


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    寒䞭コンクリヌト工事で最も留意すべきこずずしお、初期凍害の防止ず匷床増進の遅れに察する察応が挙げられる。初期凍害は、フレッシュ時から硬化初期にかけおコンクリヌト䞭の氎分が凍結するこずにより、匷床発珟の停滞などを匕き起こす被害のこずである。日本建築孊䌚の寒䞭コンクリヌト斜工指針・同解説では、初期凍害に耐える圧瞮匷床5.0 MPa、適切な空気量などが芏定されおいる。しかし、日本土朚孊䌚はコンクリヌトの初期凍害を防ぐために、15.0 MPaの圧瞮匷床が必芁の堎合がある。日本建築孊䌚ず土朚孊䌚は芏定に぀いおの盞違点が存圚する珟象により、珟圚の寒䞭指針に関する囜際芏栌の統合を行い、䞖界的範囲内における寒䞭コンクリヌト斜工珟状を調査する必芁がある。䞀方で、珟堎で有効な初期凍害の非・埮砎壊の蚺断手法が望たしいので、新しい蚺断手法を開発するこずが求められる。本研究では新しい初期凍害の防止手法も目指す。そのため、以䞊の背景を螏たえ、寒䞭コンクリヌトの品質確保のために、コンクリヌト初期凍害の蚺断および防止の技術の研究を目的ずした。囜際寒䞭指針の調査により、諞囜の寒䞭コンクリヌト斜工の珟状が把握でき、倧郚分の斜工事項の内容が同じであるが、その䞭では初期凍害に耐える匷床の違い、有効な被害蚺断・防止手法の䞍足の問題点が発芋された。そのため、たず、初期凍害に耐える匷床の違いにより、凍結融解開始前圧瞮匷床がコンクリヌトの耐凍害性に及がす圱響を明らかにした。コンクリヌトの圧瞮匷床が倧きい皋、耐凍害性が良くなる。曎に、囜際寒冷地の気象条件により、幎間の凍結融解回数であるASTM盞圓サむクル数を甚いた初期凍害に耐える匷床5.0 MPaを評䟡した。5.0 MPaは䞖界的な共通の匷床ずしお初期凍害を防止するこずが安党である。䞀方で、埮砎壊の貫入詊隓は初期凍害を蚺断できるかを怜蚎した。釘の貫入詊隓は効果が良くないが、空気圧ピン貫入詊隓機の堎合では貫入量ず被害深さの関係により、被害皋床の掚定ができる。コンクリヌトの凝結時間調敎材ACFを甚いた初期凍害防止の効果を怜蚎した。ACF材の添加量は0246kg /m3の4氎準を蚭眮した。ACF材の添加量が倚い皋、凝結時間が早くなり、䜎枩でも顕著な効果がある。添加量の2kg /m3の堎合では、初期凍害を受ける状況は0kg /m3の堎合ず同じ。添加量が46kg /m3の堎合では、初期材霡に凍結を受けたコンクリヌトが初期凍害を受けなく、圧瞮匷床は凍結なしのコンクリヌトず同等になる。ACF材添加量の46kg /m3を初期凍害の防止手法ずしお提案した。The most critical things in cold weather concreting are preventing early age frost damage and guaranteeing a normal strength development. Early age frost damage is a serious problem for concrete structures in cold regions, which is caused by freezing and cyclic freeze-thaw cycles during the initial hardening stage. The objective of this study was to (1) grasp the present situation of cold weather concreting in various countries and summarize the content from various guidelines by investigating Guides to Cold Weather Concreting of various countries, (2) propose effective diagnosis methods for early age frost damage, (3) investigate the effect of compressive strength development at early ages on frost resistance of concrete and (4) propose a prevention method of early age frost damage by using additive for setting time adjustment.Based on the literature review of Guides to Cold Weather Concreting of various countries, it is known that most of the regulations are relatively similar. However, the minimum required compressive strength is the main difference in various countries. Meanwhile, technological development is needed to improve the diagnosis and prevention of early age frost damage.The nail and pneumatic penetration test machine methods are discussed to develop accurate diagnostic methods for detecting the depth of early age frost damage. The penetration test by pneumatic penetration test machine effectively diagnoses the depth of early age frost damage in 7 days. It can roughly detect the damage depth with a micro-destructive degree.To investigate the effect of compressive strength development at early ages on the frost resistance of concrete, laboratory and outdoor exposure tests were conducted. Air-entrained concrete with a compressive strength of 5.0 MPa can withstand several freeze-thaw cycles and effectively prevent early age frost damage. Concrete that has finished its final setting can effectively resist early age frost damage in Air-entrained and Non-air-entrained conditions. To develop an effective prevention method for early age frost damage using additive for setting time adjustment, setting time test and compressive strength test are performed. Adding 4 and 6 kg/m3 of ACF additive effectively prevents early age frost damage, which can apply for cold weather concreting due to the outstanding prevention effectiveness of early age frost damage.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊


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    1. 緒蚀 金属材料の特性改善の方法ずしお匷ひずみ(SPD)加工が挙げられる。SPD加工は、巚倧な塑性倉圢によっお倚量のひずみを付䞎する方法で、様々な方法が考案されおおり、合金化、耇合化ず組み合わせおさらなる特性向䞊が期埅できる。連続匷ねじりひずみ加工法(RMA-CREO凊理)1, 2)は、長尺な䞞棒材に察し均䞀か぀連続的にSPD加工が可胜である。本研究では、RMA-CREO凊理を塑性加工性の䜎いHCP金属である玔チタン、ならびにFCC析出匷化型合金であるCu-Cr-Zr系合金ぞ適甚し、材料特性ぞ䞎える圱響を調査した。たた組織孊的調査から、結晶組織の圢成機構や埮现組織の各材料特性に察する䜜甚機序の解明を目指した。2. 玔チタンの塑性倉圢胜に及がすRMA-CREO凊理の圱響 HCP金属であるチタン合金やマグネシりム合金は高比匷床を有しおいるこずから、構造材料に広く利甚されおいる。䞀方でHCP構造由来の塑性倉圢性の䜎さが課題ずなっおいる。マグネシりム合金ぞRMA-CREO凊理を適甚するこずで、塑性倉圢胜の向䞊が報告されおいる3)。そこでマグネシりム同様にHCP構造を有し、匷床面で優れる玔チタンぞRMA-CREO凊理を適甚し、塑性倉圢胜に䞎える圱響を調査した。熱間鍛造詊隓より、RMA-CREO凊理を行った詊料の最倧倉圢抵抗が䜎䞋した。結晶方䜍解析を甚いた結晶組織調査から、詊料倖呚郚にRMA-CREO凊理によっお粗倧結晶粒を取り囲むように埮现な結晶粒が分垃するバむモヌダル組織が圢成されおいるこずが明らかずなった。このバむモヌダル組織による粗倧粒の加工硬化抑制や、埮现粒の粒界すべりが倉圢抵抗枛少に寄䞎しおいるこずが瀺唆された。3. Cu-Cr-Zr系合金の時効特性に䞎えるRMA-CREO凊理の圱響 高匷床、高導電性を有する析出匷化型合金であるCu-Cr-Zr系合金にRMA-CREO凊理を適甚し、時効特性に䞎える圱響を調査した。受入材に察しRMA-CREO凊理埌、623 Kの時効凊理を行うこずで、倧気炉を甚い溶䜓化凊理を斜した比范詊料ず同等の最倧ビッカヌス硬さ122 HVを維持しながら、時効時間は半枛し、導電率の向䞊が確認された。結晶組織調査の結果、RMA-CREO凊理による倚量の栌子ひずみの導入が確認された。栌子ひずみが析出物の優先的な栞生成サむトずなるこずで、時効時間の短瞮に寄䞎したず考えた。4. 総括 RMA-CREO凊理を塑性加工性の䜎いHCP金属である玔チタン、ならびにFCC析出匷化型合金であるCu-Cr-Zr系合金ぞ適甚し、材料特性ぞ䞎える圱響を調査した。 ・RMA-CREO凊理を適甚した玔チタンを熱間鍛造詊隓に䟛した結果、倉圢抵抗が枛少し、塑性倉圢胜の改善が確認された。 ・RMA-CREO凊理を適甚したCu-Cr-Zr系合金は、溶䜓化凊理を斜された比范詊料ず同等の最倧ビッカヌス硬さ122 HVを維持しながら、導電率が向䞊し時効時間が半枛した。参考文献1) 䞭村克昭, 堀田善治, 䞭垣道圊, 金子賢治, 根石浩叞: 特蚱公報4777775号, (2004).2) K. Nakamura, K. Neishi, K. Kaneko, M. Nakagaki, Z. Horita: Material Transactions, 45 (2004) 3338-3342.3) 䞭村克昭, 鈎朚裕, 型技術, 25 (2010), 91-92.1. IntroductionSevere plastic deformation (SPD) processing apply a large amount of distortion through huge plastic deformation for improving the metal material properties. RMA-CREO processing 1, 2) enables uniform and continuous SPD processing for long round bars. In this study, RMA-CREO processing was applied to commercially purity titanium, which is HCP metal with low plastic workability, and Cu-Cr-Zr alloy, which is FCC precipitation-strengthened alloy, and its effect on their characteristics was investigated. In addition, from the microstructure investigation, we aimed to clear the formation mechanism of the micro structure and the effect of the micro structure on each material property.2. The effect of RMA-CREO processing on plastic deformability of pure titaniumDilute titanium alloys and magnesium alloys, which are HCP metals, are widely used as structural materials because of their high specific strength. On the other hand, the low plastic deformability derived from the HCP structure has shown. Application of RMA-CREO processing to magnesium alloys has been reported to improve the plastic deformability3). Therefore, RMA-CREO processing was applied to pure titanium, which has an HCP structure such the same as and has higher strength than magnesium alloy, and the effect on plastic deformability was investigated.The maximum deformation stress of RMA-CREO processed specimens decreased for the hot forging test. From the microstructure investigation using the crystal orientation analysis, it was clarified that the RMA-CREO processing formed a bimodal structure in which fine grains were distributed so as to surround the coarse grains at the edge of the specimen. It was suggested that this bimodal structure contributes to the suppression of work hardening of coarse grains and grain boundary sliding of fine grains to reduce deformation stress.3. The effect of RMA-CREO processing on aging property of Cu-Cr-Zr alloyRMA-CREO processing was applied to Cu-Cr-Zr alloys, which are precipitation-strengthened alloys with high strength and high electrical conductivity, and the effects on aging properties were investigated. RMA-CREO processed specimen aged at 623 K reduced the aging time to peak Vickers hardness by half while maintaining the maximum hardness of 122 HV which is equivalent to the comparative solution treated specimen. Furthermore, an improvement in electrical conductivity was confirmed. As a result of the microstructure investigation, it was confirmed that a large amount of distortion was introduced by the RMA-CREO processing. It was thought that the distortion serves as preferential nucleation sites for precipitates, which contributes to the shortening of the aging time to peak hardness.1) K. Nakamura et al.: Published unexamined patent application No. 4777775, (2004).2) K. Nakamura et al.: Materials Transactions, 45 (2004) 3338-3342.3) K. Nakamura et al.: Die and Mould Technology, 25 (2010), 91-92.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊


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    珟圚、超音波を甚いた様々な珟象を甚いお物䜓の浮揚や䜍眮制埡が実珟されおいる。近距離堎音波浮揚は板状物䜓が振動面から音響攟射力を受け数癟µm皋床、浮揚し保持力によっお振動面䞊を保持する珟象である。この保持力を甚いるこずによっお、板状物䜓の非接觊2次元ステッピング搬送が実珟されおいる。しかし、振動面䞊に窪みを有しおおり非平面である堎合は振幅を増加させるこずで板状物䜓が非平面の振動面から跳躍するこずが確認された。たた、平面の振動面䞊に貫通穎を有する物䜓を貫通穎が振動面に重なるように配眮するず穎から空気が噎出するこずが確認された。このような振動面䞊からの跳躍珟象および穎からの流䜓噎出珟象はこれたで報告されおおらず、詳现な怜蚎により超音波の新たな分野が開拓されるこずが期埅できる。さらに、これらの珟象を利甚するこずで新しい超音波デバむスの開発に応甚できるず考えられる。以䞊の理由から本研究では実隓ず解析から跳躍珟象および流䜓噎出珟象に぀いお詳现に怜蚎し、明らかにした。たた、その珟象を利甚した応甚方法を提案した。跳躍珟象は振動面からの距離に察する音響攟射力の極小倀が浮揚物䜓重量を䞊回るこずで発生するこずを明らかにした。たた、振動面䞊の䞭心からずれた䜍眮に溝を蚭けるこずによっお板状物䜓の非接觊反転動䜜が実珟できた。この非接觊反転動䜜ず近距離堎音波浮揚を利甚した非接觊ステッピング搬送を組み合わせるこずによっお、板状物䜓の非接觊の搬送ず反転動䜜可胜になるこずが期埅できる。振動面近傍に配眮された穎を持぀物䜓の流䜓噎出珟象による流速分垃はPIV蚈枬により蚈枬された。PIV蚈枬結果より振動面ず穎付き物䜓間には空気が流入せず、穎からの噎出流は穎近傍の空気を吞匕した穎軞䞊に排出する珟象であるこずが明らかずなった。したがっお、穎からの噎出流は流入郚ず流出郚が近くなるが、穎に察向する䜍眮に分離甚の穎を蚭けるこずによっお流入郚ず流出郚を分離するこずができた。たた、平面䞊に穎付きの円筒を配眮し、䞊偎から振動面を近づけるず穎付き円筒が浮揚し、さらに浮揚円筒には10mNの保持力が䜜甚した。10mNの保持力は近距離堎音波浮揚における保持力よりも玄10倍倧きい保持力ずなり、この浮揚方法を甚いた無重力空間における新しい浮揚保持ぞの応甚方法を提案した。Currently, the levitation and position control of an object has been developed by some ultrasonic phenomena. A planar object is levitated several hundred µm from a vibrating surface by near-field acoustic levitation (NFAL) phenomenon. The object was held by the holding force above the vibrating surface. This holding force was applied to the non-contact stepping transportation. However, when the vibrating surface has a recess, the planar object above the surface is jumped from the surface. In addition, the jet generated from the hole when the object has a through hole. These phenomena have not been reported before. A detailed examination of these phenomena was expected to extend new ultrasonic fields. Novel ultrasonic devices will be able to be applied by these phenomena. Therefore, this thesis described these phenomena to clear and suggestions about ultrasonic devices using these phenomena.The jumping phenomenon of the levitated object happened when the minimum force of the acoustic radiation force was larger than the object’s weight. The flip motion was realized by the asymmetric vibrating surface by a groove of a deviation position from a vibrating surface center. This thesis suggested combining non-contact stepping transportation by NFAL and flip motion.The jet phenomenon by an object with a small hole near the vibrating surface was measured by particle image velocimetry (PIV). The air did not flow in the air gap between the vibrating surface and the small hole of the object. The air around the small hole was absorbed, and then it was emitted from the hole. The inflow part and the outflow part of the jet were generated near each. The jet flow was separated by the separation hole at the opposite small hole. In addition, a cylinder with a small hole is levitated above the vibrating surface. The holding force acted on the levitated cylinder. The holding force reached 10mN. This force value is more than about 10 times larger than the holding force by NFAL. This levitation method was suggested to apply in zero gravity space in this thesis.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊


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    近幎の通信システムの倧容量化に䌎い、ミリ波およびテラヘルツ波垯域の䜿甚が積極的に怜蚎されおいる。非攟射性誘電䜓導波路(NRDガむド)は、非攟射性により䜎損倱なため倚くの泚目を集めおいる。これたで提案されおいるNRDガむドデバむスは、基本的な構造によるものが䞻である。さらに、NRDガむドはその構造から3次元解析手法がしばしば䜿甚され垂販の゜フトりェアでは蚈算コストが高くなる。この論文では、モザむク圢状を甚いたNRDガむドの最適蚭蚈に぀いおいく぀かの最適蚭蚈アプロヌチを提案する。蚈算コストを削枛するために、効率の高いシミュレヌション手法も開発した。 はじめに、盎接二倀探玢法(DBS)を開発した。蚭蚈効率を向䞊させるため、数倀シミュレヌション手法ずしお独自に開発した2次元フルベクトル有限芁玠法(2D-FVFEM)を採甚しおいる。有甚性を瀺すために、NRD垂販の亀差導波路ず90°曲り導波路の蚭蚈を行い、いずれも99%を超える高い䌝送効率が埗られた。次に、バむナリベヌスの遺䌝的アルゎリズム、差分進化アルゎリズム、ハヌモニヌサヌチアルゎリズム、蛍アルゎリズム、粒子矀最適化アルゎリズムを提案する。有甚性を瀺すために、亀差導波路、T分岐導波路、曲り導波路、および呚波数分離玠子の蚭蚈を行った。それぞれの透過率は、亀差導波路が99.9%、T分岐導波路が49.9%:49.9%、曲り導波路では96.4 %、呚波数分離玠子では59 GHzで96.4 %、61 GHzで98.5 %が埗られおいる。 次に、これたでに開発した2D-FVFEMを、非盞反性材料を含んだNRDガむドデバむスの蚭蚈に適応できるように拡匵し、サヌキュレヌタずアむ゜レヌタの蚭蚈をするこずにより劥圓性を確認した。所望の特性を達成するために、ハヌモニヌサヌチず差分進化法を適甚し、単䞀呚波数での動䜜ず広垯域化を実珟した。 次に、NRDガむドデバむスの解析のための厳密な2次元フルベクトル有限差分時間領域法(2DFDTD)を提案する。吞収境界条件ずしお、畳み蟌み完党敎合局(CPML)を甚いた。さらに、LSM01ずLSE01の各モヌドの透過率を掚定するために厳密な定匏化を確立した。NRDガむド亀差導波路、T分岐導波路の解析を通しおこの手法の有効性を瀺した。この研究では、いく぀かの最適蚭蚈アプロヌチずシミュレヌション手法を開発しおいる。私達が提案する蚭蚈アプロヌチは、耇雑なデバむス構造ず機胜を備えた倚くのNRDガむドデバむスの蚭蚈にも適甚できる。蚭蚈されたデバむスは小型で高性胜なミリ波回路を実珟するために十分な胜力ず可胜性を持っおいる。The use of millimeter- and terahertz-wave bands are being actively explored to increase communication system capacity and meet modern communication requirements. In recent years, non-radiative dielectric (NRD) waveguide device has received a lot of attention due to low loss nature. Several NRD guide components have been reported so far without employing any optimization approaches. On the other hands, those devices are simulated numerically using 3D simulation methods and commercially available softwares result in high computational time and simulation resources required. In this thesis, we propose several optimal design approaches based on mosaic optimization concept for the design of NRD guide. In order to reduce the computational cost, we also developed highly efficient simulation methods.First, we develop direct binary search (DBS) algorithm. In order to improve design efficiency, we employ the originally developed two-dimensional full vectorial finite element method (2D-FVFEM) as a numerical simulation method. To show the usefulness, NRD crossing and 900-bend waveguide are considered and high transmission efficiency greater than 99% is achieved at operating frequency 60 GHz. Then, we propose binary representation-based genetic algorithm, differential evolution algorithm, harmony search algorithm, firefly algorithm, and particle swarm optimization. To show the usefulness, four NRD circuit components are designed which include low crosstalk waveguide crossing, T-branch power splitter, bending waveguide, and frequency demultiplexer. The proposed optimal devices achieve high transmission efficiencies greater than 99.9%, 49.9%:49.9%, 99.9% at 60 GHz and 96.4%, 98.5% at 59 GHz and 61 GHz. In addition, the same NRD guide components except frequency demultiplexer are also designed at wideband operation and achieve broad bandwidth around 5 GHz, 4 GHz, and 3 GHz.We extend our previously developed 2D-FV-FEM to be applicable for design of non-reciprocal NRD guide devices. The accuracy is confirmed by designing NRD circulator and isolator. To achieve the desired properties, harmony search and differential evolution algorithm are employed for single frequency and broadband operation respectively.We propose rigorous two-dimensional full-vectorial finite difference time domain method for the analysis of NRD guide devices. Convolutional perfectly matched layer (CPML) is employed as an absorbing boundary condition. Furthermore, we have established a rigorous formulation for estimating the modal power of each LSM01 and LSE01 mode. We confirmed the validity of the proposed method through the analysis of NRD crossing and T-branch guide devices. Excellent accuracy is achieved by the cross comparison of 2D-FV-FDTD results with 2D-FV-FEM.In this research work, we develop several optimal design approaches and simulation methods. Our proposed design approaches are applicable to design a lot of NRD guide devices with complex device structures and functionalities as well. The designed devices have enough ability and potential to integrate in a circuit for the realization of complex, compact and high-performance millimeter- wave circuit.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊


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    本研究では、98ケヌスの圧密非排氎単調・繰返し䞉軞詊隓結果に基づいお、単調および繰返し茉荷による流動化凊理土および補匷された流動化凊理土LSSの力孊挙動に぀いお議論されおいる。単調茉荷詊隓では、LSSの匷床・倉圢特性に及がす泥氎密床、逊生日数の圱響を怜蚎するずずもに、綿状に粉砕した新聞玙を0, 10 kg/m3で混合した宀内および原䜍眮逊生の繊維材混合流動化凊理土が比范・怜蚎された。詊隓結果に基づいお、LSSの匷床特性に及がす泥氎密床の圱響は、逊生日数の圱響よりも倧きいこずが明らかにされた。たた、ピヌク前のqa関係の挙動は、逊生日数の圱響ずは察照的に泥氎密床の圱響でより非線圢的になるこず、LSSのせん断による損傷皋床は、逊生日数の増倧ずずもに小さくなるが、泥氎密床にはあたり䟝存しないこずが明らかずなった。繰返し茉荷詊隓では、倉圢特性に及がす繰返し茉荷の圱響を怜蚎する目的で、宀内で28日間逊生した流動化凊理土に察しお、軞差応力振幅、初期応力、圧密圧力、ひずみ速床、制埡方法応力-ひずみサむクルなどを倉化させるずずもに、泥氎密床、繊維材混合量、セメント添加量などの流動化凊理土材料を倉化させたその結果、流動化凊理土および繊維材で補匷された流動化凊理土は液状化を生じないこずが明らかずなった。たた、砎壊モヌドは、繰返し軞差応力振幅ず初期軞差応力に䟝存するこず、等方応力状態から䞀定の軞差応力振幅で茉荷した堎合、間隙氎圧ず䞡振幅軞ひずみは繰返し茉荷回数の増加ずずもに増加するこず、繊維材混合流動化凊理土は、かなり倧きなひずみ振幅により、最終的に砎壊に至るこず、最終段階における有効応力履歎ルヌプは、バタフラむ圢状の応力経路ずなるこずなどが明らかにされた、たた、茉荷䞭立軞の軞差応力を正の倀にした繰返し茉荷では、それぞれの繰返し茉荷に䌎っお軞ひずみの蓄積が生じ、動員される䞡振幅軞ひずみはほずんど䞀定に保たれる。したがっお、氞久ひずみの過倧な蓄積により砎壊芏準は満たされるこずになる。最終段階の応力ルヌプの圢状は、バタフラむ型やレンズ型にはならず、限界状態線(CSL)を越えた埌、再び戻っおくる経路ずなった。これは、繊維材混合流動化凊理土は砎壊芏準線に到達する前に膚匵傟向になるこずを意味する。応力レベルを瀺す繰返し応力比CSRの範囲は0.2750.344であった。応力レベルがこの範囲より小さい堎合、流動化凊理土は蓄積される氞久軞ひずみにより膚匵傟向を瀺し砎壊には至らない。流動化凊理土の繰返しせん断抵抗は、初期平均有効応力ず固化材量が枛少するず枛少し、繊維材混合量や泥氎密床を増加するず増加するこずが明らかになった。有限芁玠法は地震振動解析に広く甚いられおいるが、その結果は構成匏ず数倀解析に適甚されるモデルパラメヌタに倧きく䟝存する。本研究では流動化凊理土の挙動を解析するための特定のモデル、Ramberg-OsgoodモデルのDelphiコヌドぞの実装が行われた。解析倀ず実隓倀の比范から、流動化凊理土の繰返し茉荷挙動の評䟡にRamberg-Osgoodモデルが適甚可胜であり、動的パラメヌタは適切に校正される必芁があるこずが明らかずなった。以䞊より、単調および繰返し茉荷を受ける補匷された流動化凊理土の力孊的挙動に関しお、倚くの新たな知芋が瀺された。In this study, the mechanical behavior of reinforced and unreinforced Liquefied Stabilized Soil (LSS) subjected to monotonic and cyclic loading is discussed based on a database with about Consolidated-Undrained monotonic and cyclic triaxial tests of 98 cases.In the monotonic tests, the influences of slurry density and curing time on the strength and deformation of LSS are investigated. Also, LSS mixed with the pulverized newspaper in the amount of 0 and 10 kg/m3 cured laboratory and in-situ are compared and investigated. Based on the test results, the effect of slurry density on the strength of LSS was found to be greater than the effect of curing time. The pre-peak behavior of the q~a curve became more non-linear under the effect of changing slurry density, in contrast to the effect of curing time. Moreover, the damage degree of LSS with shearing becomes small with curing time, while it seems to be rather independent of slurry density. With in-situ LSS, the influence of curing time on the initial Young’s modulus, E0, is lower than the effect of slurry density.In the cyclic tests, in order to investigate the effect of cyclic load on the deformation property, the deviator stress amplitude, the initial stress, consolidation pressure, strain rate, and the control method (stress vs. strain cycles) were changed and LSS material which includes slurry density, fiber material, and cement base agent on LSS cured 28 days at the laboratory have been also varied. Based on the test results, it is found that the true liquefaction (q = p = 0) did not reach reinforced and unreinforced LSS. The failure mode is highly dependent on the cyclic deviator stress amplitude (σ_d) and initial deviator stress (σ_s). For symmetrical loading (σ_(s )= 0), the pore water pressure and double amplitude axial strain grew with an increasing number of cycles. LSS mixed with fiber material finally collapsed due to too large strain amplitudes. In the final stage, the loops of effective stress indicate a “Butterfly” stress path shape. For nonsymmetrical loading (σ_(s )> 0), an accumulation of compressional axial strain with each subsequent cycle occurred, while the mobilized double amplitude axial strain remained almost constant. Therefore, the failure criterion was fulfilled due to an excessive accumulation of permanent strains. The shape of the stress loop at the final stage did not pass the “butterfly” shape or lens shape to migrate to pass over the Critical State Line (CSL), then return to the touch again of the failure envelope. It means the LSS mixed fiber material tends to dilate before reaching the failure criterion. The range of critical cyclic stress ratio (CSR), which indicates the limitation of stress level, was between 0.275 to 0.344. If the stress level is lower than that value, the LSS sample is more dilative by accumulating permanent axial strain and does not reach failure. The cyclic shear resistance of LSS decreases when reducing the initial mean effective principal stress and cement content. In contrast, the cyclic shear resistance increases when adding fiber and increasing slurry density.The Finite Element Method (FEM) is used widely in the analysis of seismic vibration. However, the results depend critically on the constitutive models used and the model parameters adopted in the numerical analyses. The implementation of a specific model to analyze the behavior of LSS mixed fiber material under cyclic loading, the Ramberg-Osgood model, in the Delphi code is performed. Based on the result of the comparison of model simulations with experimental data, the overall is able to apply the Ramberg-Osgood model to evaluate the cyclic loading behavior of LSS, and dynamic parameters should be calibrated properly. In summary, a number of new findings were presented regarding the mechanical behavior of reinforced, liquefied stabilized soils subjected to monotonic and cyclic loading.宀蘭工業倧孊 (Muroran Institute of Technology)博士工孊


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