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Engineering 2021年第1期7卷 111-123页

作者： Khawaja Ali Hiroshi Katsuchi hitoshi yamada Department of Civil Engineering Yokohama National UniversityYokohama 240-8501Japan

This study provides new insights into the comparison of cable-stayed and extradosed bridges based on the safety assessment of their stay *** bridges are often regarded as identical structures owing to the use of inclined cables;however,the international standards for bridge design stipulate different safety factors for stay cables of both types of *** address this misconception,a comparative study was carried out on the safety factors of stay cables under fatigue and ultimate limit states by considering the effects of various untoward and damaging factors,such as overloading,cable loss,and *** primary goal of this study is to describe the structural disparities between both types of bridges and evaluate their structural redundancies by employing deterministic and nondeterministic *** achieve this goal,three-dimensional finite-element models of both bridges were developed based on the current design guidelines for stay cables in *** the balanced states of the bridge models were achieved,static analyses were performed for different safety factors of stay cables in a parametric ***,the first-order reliability method and Monte Carlo method were applied to determine the reliability index of stay *** analysis results show that cable-stayed and extradosed bridges exhibit different structural redundancies for different safety factors under the same loading ***,a significant increase in structural redundancy occurs with an incremental increase in the safety factors of stay cables.

关键词： Cable-stayed bridge Extradosed bridge Redundancy Stay cable Safety factor Reliability analysis

Improvement of aerodynamic stability of suspension bridges with H-shaped simplified stiffening girder

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Frontiers of Structural and Civil Engineering 2016年第1期10卷 93-102页

作者： Hiroshi KATSUCHI hitoshi yamada Mayuko NISHIO Yoko OKAZAKI Department of Civil Engineering Yokohama National University Yokohama 240-8501 Japan

Wind-tunnel study on the improvement of aerodynamic stability of simplified suspension-bridge girder structures was conducted with using a 1/40-scaled section model. Objective of the study is the development of an economically superior suspension bridge with 500-1,000 m center span length. The wind-tunnel test showed that an edge-girder type cross section exhibited large amplitude torsional vortex-induced vibration as well as torsional flutter at a low wind speed. Accordingly, aerodynamic countermeasures of open grating deck and triangular fating, and structural countermeasures of center stay, diagonal bracing and mass increase were tried to improve the aerodynamic stability. Finally, feasibility of the best combination to a full-scale bridge was examined by structural analysis.

关键词： suspension bridge aerodynamics simplified girder wind-tunnel test

Investigation of Turbulence Effects on the Aeroelastic Properties of a Truss Bridge Deck Section

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Engineering 2017年第6期3卷 845-853页

作者： Hoang Trong Lam Hiroshi Katsuchi hitoshi yamada The University of Danang-University of Science and Technology Danang Vietnam Yokohama National University Yokohama 240-8501 Japan

本文介绍了在不同湍流条件下通过随机系统识别(SSI)方法提取颤振导数(FD)的过程。研究旨在通过对节段模型风洞试验来研究湍流对悬索式大跨度桥梁的影响。针对不同的湍流特性,对桁架式桥梁断面进行了几项风洞试验,包括降低湍流强度和湍... 详细信息

本文介绍了在不同湍流条件下通过随机系统识别(SSI)方法提取颤振导数(FD)的过程。研究旨在通过对节段模型风洞试验来研究湍流对悬索式大跨度桥梁的影响。针对不同的湍流特性,对桁架式桥梁断面进行了几项风洞试验,包括降低湍流强度和湍流尺度。研究包括湍流对模型动态响应的影响。利用系统识别技术提取FD,对风洞试验中的瞬态响应和抖振响应进行了分析,同时讨论了该方法存在的困难。利用时域SSI同时从一自由度(1DOF)和二自由度(2DOF)系统提取所有的FD。最后,讨论了不同情况下的结果并得出结论。

关键词：颤振导数系统识别湍流效应抖振响应

Wind-Tunnel Investigation of the Aerodynamic Performance of Surface-Modification Cables

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Engineering 2017年第6期3卷 817-822页

作者： Hiroshi Katsuchi hitoshi yamada Ippei Sakaki Eiichi Okado Yokohama National University Yokohama 240-8501 Japan Shinko Wire Company Ltd. Amagasaki 660-0091 Japan

学界对包括风雨激振(RWIV)和干索驰振(DG)在内的斜拉桥拉索的风致振动等的研究已经有相当长的时间。一般来说,我们会应用机械阻尼器或表面处理来抑制振动。特别是已开发出几种表面处理拉索,包括压痕、纵向平行突起、螺旋角和U形开槽。... 详细信息

学界对包括风雨激振(RWIV)和干索驰振(DG)在内的斜拉桥拉索的风致振动等的研究已经有相当长的时间。一般来说,我们会应用机械阻尼器或表面处理来抑制振动。特别是已开发出几种表面处理拉索,包括压痕、纵向平行突起、螺旋角和U形开槽。最近又开发了一种带螺旋突起的新型空气动力学稳定拉索,这种拉索已被证明具有与锯齿状拉索相似的低阻力系数,并且可以防止拉索表面形成水线。在本研究中,应用风洞实验对这种拉索在各种来流角度和突起尺寸下的RWIV稳定性进行了研究。发现对于所有测试风角,螺旋突起拉索对于RWIV和DG在空气动力学基础上都能保持稳定,突起尺寸的影响也得到了确认。

关键词：风雨激振干索驰振斜拉索风洞实验

A wind tunnel study on control methods for cable dry-galloping

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Frontiers of Structural and Civil Engineering 2016年第1期10卷 72-80页

作者： Hung D. VO Hiroshi KATSUCHI hitoshi yamada Mayuko NISHIO Department of Civil Engineering Yokohama National University Yokohama 240-8501 Japan

The common vibration of cable caused by rain-wind combination has been known as most typical type and a lot kind of its countermeasures has been proposed for suppressing this phenomenon. Recently, stayed-cables were also proved that they could be excited in dry state （without rain）, which is called dry-galloping. Recently, its mechanisms have been explained by axial flow, Reynolds number and so on. To clarify the characteristics of this galloping, wind tunnel test of a cable model with various kinds of wind angle was conducted. Then, three types of countermeasure were examined to suppress dry- galloping of bridge cable. The tests confirmed that the occurrence of dry-galloping depends on relative wind attacked angles and onset reduced wind speed. Furthermore, single spiral wire, double spiral wire and circular ring were found to have high effectiveness in mitigating this galloping when those are installed properly.

关键词： dry-galloping wind-relative angle single spiral wire double spiral wire circular rings

Effects of elafibranor on liver fibrosis and gut barrier function in a mouse model of alcohol-associated liver disease

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World Journal of Gastroenterology 2024年第28期30卷 3428-3446页

作者： Aritoshi Koizumi Kosuke Kaji Norihisa Nishimura Shohei Asada Takuya Matsuda Misako Tanaka Nobuyuki Yorioka Yuki Tsuji Koh Kitagawa Shinya Sato Tadashi Namisaki Takemi Akahane hitoshi Yoshiji Department of Gastroenterology Nara Medical UniversityKashihara 634-8521Japan

BACKGROUND Alcohol-associated liver disease(ALD)is a leading cause of liver-related morbidity and mortality,but there are no therapeutic targets and modalities to prevent ALD-related liver *** proliferator activated receptor(PPAR)α and δ play a key role in lipid metabolism and intestinal barrier homeostasis,which are major contributors to the pathological progression of ***,elafibranor(EFN),which is a dual PPARαand PPARδagonist,has reached a phase III clinical trial for the treatment of metabolic dysfunctionassociated steatotic liver disease and primary biliary ***,the benefits of EFN for ALD treatment is *** To evaluate the inhibitory effects of EFN on liver fibrosis and gut-intestinal barrier dysfunction in an ALD mouse *** ALD-related liver fibrosis was induced in female C57BL/6J mice by feeding a 2.5% ethanol(EtOH)-containing Lieber-DeCarli liquid diet and intraperitoneally injecting carbon tetrachloride thrice weekly(1 mL/kg)for 8 ***(3 and 10 mg/kg/day)was orally administered during the experimental *** and molecular analyses were performed to assess the effect of EFN on steatohepatitis,fibrosis,and intestinal barrier *** EFN effects on HepG2 lipotoxicity and Caco-2 barrier function were evaluated by cell-based *** The hepatic steatosis,apoptosis,and fibrosis in the ALD mice model were significantly attenuated by EFN *** promoted lipolysis and β-oxidation and enhanced autophagic and antioxidant capacities in EtOH-stimulated HepG2 cells,primarily through PPARα***,EFN inhibited the Kupffer cell-mediated inflammatory response,with blunted hepatic exposure to lipopolysaccharide(LPS)and toll like receptor 4(TLR4)/nuclear factor kappa B(NF-κB)*** improved intestinal hyperpermeability by restoring tight junction proteins and autophagy and by inhibiting apoptosis and proinflammatory *** protective effect on intestinal bar

关键词： Liver fibrosis Ethanol Gut barrier function Apoptosis Autophagy Peroxisome proliferator activated receptor

Japanese Mythology From Ethnological Perspectives

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History Research 2013年第5期3卷 309-316页

作者： hitoshi yamada Tohoku University Sendai Japan

Comparative studies of Japanese mythology have developed since the 1920s above all through efforts of Japanese ethnologists. They have paid attention to the possible ethno-cultural complexes that brought mythological motifs into the archipelago. In the present paper the theories set forth by Nobuhiro Matsumoto, Akihide Mishina, and Masao Oka are examined in terms of retrospect. The result shows that they shared the view that at least three different complexes, based in ancient Yamato, Izumo, and Kyushu respectively, contributed to the formation of Japanese mythology compiled in the 8th century CE (Common Era). Their assumptions were synthesized by Taryo Obayashi in 1961, the hypothesis which has survived until today. In future we should cooperate with other disciplines and address the formation process of Japanese mythology.

关键词：民族学神话日本民族文化复合物

Comparison of minimally invasive glaucoma surgery with trabecular micro-bypass stent and microhook ab interno trabeculotomy performed in conjunction with cataract surgery

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International Journal of Ophthalmology(English edition) 2022年第7期15卷 1082-1088页

作者： Naoto Tokuda Yasushi Kitaoka Ayaka Tsukamoto Yasuhiro Toyoda Yusuke yamada Kana Sase hitoshi Takagi Department of Ophthalmology St Marianna University School of Medicine2-16-1 Sugao Miyamae-ku Kawasaki-shiKanagawa 216-8851Japan

AIM: To evaluate the effectuality and safety of cataract surgery combined with either ab interno trabeculotomy by the microhook(μLOT) or a single i Stent? trabecular bypass implantation(i Stent) in eyes with cataract and mild-tomoderate glaucoma. METHODS: This study enrolled subjects with mild-tomoderate open angle glaucoma with visually significant cataract who used two or more ophthalmic antiglaucoma agents between 60 and 90 y of age. Patients underwent cataract surgery cooperated with either implantation of an i Stent(i Stent-phaco) or excisional goniotomy with the μLOT(μLOT-phaco). Patients underwent μLOT-phaco in the eye with lower the mean deviation, according to the Humphrey field analyzer, while i Stent-phaco was carried out on the other eye. Intraocular pressure(IOP) pre-and post-surgery, alterations in anterior chamber flare(ACF), and corneal endothelial cell density(ECD) were ***: Twenty subjects were enrolled(mean age: 73.6±7.3 y). The mean medicated preoperative IOP was 16.7 mm Hg in the μLOT and 16.2 mm Hg in the i Stent eyes. The mean final IOP at 12 mo was 13.6 mm Hg in the μLOT eyes and 13.6 mm Hg in the i Stent eyes, representing a 17.8% and 17.2% reduction, respectively. The preoperative ACF in the μLOT eyes was 9.5 pc/ms and it returned to normal in 30 d postoperatively, with a value of 11.4 pc/ms. In the i Stent eyes, ACF was 9.6 pc/ms preoperatively and it returned to normal by 7 d postoperatively(11.2 pc/ms atday 7), demonstrating that postoperative inflammation was less in the i Stent eyes. The corneal ECD in both groups was not significantly ***: In this study, i Stent and μLOT are both effective through 12 mo of follow-up. Safety is more favorable in the i Stent eyes, based on early anterior chamber inflammation.

关键词： minimally invasive glaucoma surgery iStent ab interno trabeculotomy

特朗普政府及新冠疫情对全球经济的影响回顾——聚焦中美关系

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日本研究 2024年第1期 74-87页

作者： [日]平川均张帅(译) 日本名古屋大学南开大学辽宁大学《日本研究》编辑部沈阳110136

由于美国前总统特朗普的“美国优先”对华政策,2018年开始的中美贸易战以及随后的新冠疫情促使中美贸易摩擦尖锐化。这场因贸易逆差引发的冲突不仅升级为两国之间的关税争端,还扩大到知识产权争端、不公平产业政策、技术霸权、国家安全... 详细信息

由于美国前总统特朗普的“美国优先”对华政策,2018年开始的中美贸易战以及随后的新冠疫情促使中美贸易摩擦尖锐化。这场因贸易逆差引发的冲突不仅升级为两国之间的关税争端,还扩大到知识产权争端、不公平产业政策、技术霸权、国家安全风险、人权问题、国家体制和意识形态问题等。2021年上台的美国拜登政府尝试扩展以民主价值观为纽带的联盟体系,制衡发展中的中国。另一方面,中国希望通过自身努力实现国内产业结构升级,提出“一带一路”倡议推动国际合作。世界经济正朝着形成独立经济集团的方向发展,中美两国在争夺先进战略产业和企业的同时,也有可能诞生一个新的经济集团。政治上意识形态的冲突将加剧,但在全球经济领域,中美两国之间的竞争将推动围绕“一带一路”倡议的非洲—欧亚经济基础设施的发展。

关键词：中美贸易战 “特朗普交易” 贸易逆差知识产权技术霸权

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On systematic development of FSI solvers in the context of particle methods

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Journal of Hydrodynamics 2022年第3期34卷 395-407页

作者： Abbas Khayyer hitoshi Gotoh Yuma Shimizu Department of Civil and Earth Resources Engineering Kyoto UniversityKyotoJapan

This paper presents a review on state-of-the-art of developments corresponding to fluid-structure interaction(FSI)solvers developed within the context of particle *** paper reviews and highlights the potential robustness of entirely Lagrangian meshfree FSI solvers in reproducing FSI corresponding to extreme events and portrays the future perspectives for systematic developments towards reliable engineering applications with respect to rapid advances in technology and emergence of so-called advanced materials that can result in complex and highly non-linear structural ***,the paper highlights the necessity for reproduction of comprehensive structural responses,including viscoelastic,elastoplastic and progressive damages/failures,by the advanced FSI solvers developed within the context of particle *** this regard,extensions of the structure model are suggested to be conducted in a variationally consistent framework to ensure stability,accuracy and physical reliability including thermodynamic *** paper reviews basics of mathematical and numerical modelling for entirely Lagrangian meshfree hydroelastic FSI solvers and presents a brief background on extensions of such solvers towards reproducing viscoelastic structural *** preliminary numerical results on structural viscoelasticity achieved by an extended Hamiltonian SPH(HSPH)model are *** vision paper also concisely portrays the future perspectives for systematic development of particle-based FSI solvers.

关键词： Fluid-structure interaction(FSI) entirely Lagrangian meshfree smoothed particle hydrodynamics(SPH) Hamiltonian SPH(HSPH) viscoelasticity