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大型集装箱船拖曳水池敞开式风场中风阻试验与数值计算

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上海交通大学学报 2016年第3期50卷 389-394页

作者：罗少泽马宁平川嘉昭顾解忡上海交通大学船舶与海洋建筑工程学院上海200240 上海交通大学海洋工程国家重点试验室上海200240 上海交通大学高新船舶与深海开发装备协同创新中心上海200240 日本横滨国立大学海空制御系统研究室

就拖曳水池开展了风场研究,对敞开式风场风阻试验进行了可行性验证.在此基础上,对一缩尺比为1.0∶87.5的3 100箱集装箱船模进行了风阻测试与集装箱布置优化分析,结合一系列布置方案试验结果以及计算流体力学CFD数值模拟计算,讨论了集装... 详细信息

就拖曳水池开展了风场研究,对敞开式风场风阻试验进行了可行性验证.在此基础上,对一缩尺比为1.0∶87.5的3 100箱集装箱船模进行了风阻测试与集装箱布置优化分析,结合一系列布置方案试验结果以及计算流体力学CFD数值模拟计算,讨论了集装箱布置对船舶风阻的影响.结果表明:敞开式风场中风阻试验是一种简单有效的新式测量方法;试验结果与CFD及ITTC推荐公式进行了交叉验证,具有一定可靠性,CFD在精度与细节模拟上效果更佳;布置优化可以有效减少大型集装箱船风阻.

关键词：大型集装箱船敞开式风场风阻试验方法布置优化

Normalization of VIIRS DNB images for improved estimation of socioeconomic indicators

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International Journal of Digital Earth 2021年第5期14卷 540-554页

作者： Man Duc Chuc Tsubasa hirakawa Hiromichi Fukuic Graduate School of Engineering Chubu UniversityKasugaiJapan Chubu Institute for Advanced Studies Chubu UniversityKasugaiJapan Chubu Institute for Advanced Studies and International Digital Earth Applied Science Research Center(IDEAS) Chubu UniversityKasugaiJapan

Monthly Visible Infrared Imaging Radiometer Suite(VIIRS)Day-Night Band(DNB)composite data are widely used in research,such as estimations of socioeconomic parameters.However,some surface conditions affect the VIIRS DNB radiance,which may create some estimation bias in certain regions.In this paper,we propose a novel normalization algorithm for VIIRS DNB monthly composite data.The aim is to normalize VIIRS radiance,collected under different surface conditions,to a reference point,so that the bias is reduced.The algorithm is based on the utilization of stable lit pixels as a reference and a nonlinear regression algorithm,to match un-normalized data to the reference data.Experimental results show that the algorithm could improve correlation(R2)between the total sum of nightlights(TOL),electric power consumption(EPC),and gross domestic product(GDP)at both a global and local scale.The algorithm could significantly diminish the seasonal component of un-normalized nightlights radiance caused by snow.The intensified nightlights radiance in sandy regions could also be reduced to a more reasonable range in comparison with other regions.Visual inspection shows that the brightness of snow-affected and sandy regions was strongly reduced after undergoing normalization.

关键词： VIIRS DNB seasonal factors stable lit normalization socioeconomic indicators

Deep-nanometer-scale terahertz spectroscopy using a transistor geometry with metal nanogap electrodes

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Light(Advanced Manufacturing)

Light(Advanced Manufacturing) 2021年第4期2卷 67-79页

作者： Ya Zhang Shaoqing Du Kazuhiko hirakawa Institute of Engineering Tokyo University of Agriculture and TechnologyKoganei-shiTokyo184-8588Japan Institute of Industrial Science University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan Institute for Nano Quantum Information Electronics University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan

Terahertz(THz)spectroscopy is a powerful tool for characterizing electronic properties and vibronic excitations in various types of solids,liquids,and gases,and it has been extensively used not only for basic science but also for industrial applications.Recently,it has become necessary to understand electronic and vibronic excitations at the nanometer(nm)scale to realize state-of-the-art quantum nanodevices and the synthesis of new molecules for medicine.However,it is challenging to perform THz spectroscopy at the nm scale because the diffraction limit of electromagnetic waves hinders tight focusing of THz radiation at the nm scale.Here,we introduce a novel technique for THz spectroscopy using metal nanogap electrodes.Metal nanogap electrodes integrated with a THz antenna are employed to capture sensing targets,such as a single semiconductor quantum dot(QD)or molecule.Even extremely weak THz absorption can be detected with high sensitivity by measuring the THz-induced photocurrent through the sensing target.Taking advantage of THz-induced photocurrent spectroscopy,the electronic structures in single QDs as well as the vibrational states in single molecules are systematically investigated.The present characterization technology for nm-scale systems provides a key scientific foundation for creating nanodevices with new functions.

关键词： transistor antenna quantum

Simplification of vacuole structure during plant cell death triggered by culture filtrates of Erwinia carotovora

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Journal of Integrative Plant Biology 2015年第1期57卷 127-135页

作者： Yumi hirakawa Toshihisa Nomura Seiichiro Hasezawa Takumi Higaki Department of Integrated Biosciences Graduate School of Frontier Sciences The University of Tokyo RIKEN Center for Sustainable Resource Science

Vacuoles are suggested to play crucial roles in plant defense-related cell death. During programmed cell death, previous live cell imaging studies have observed vacuoles to become simpler in structure and have implicated this simplification as a prelude to the vacuole＇s rupture and consequent lysis of the plasma membrane. Here, we examined dynamics of the vacuole in cell cycle-synchronized tobacco BY-2 （Nicotiana tabacum L. cv. Bright Yellow 2） cells during ceil death induced by application of culture filtrates of Erwinia carotovora. The filtrate induced death in about 90% of the cells by 24 h. Prior to cell death, vacuole shape simplified and endoplasmic actin filaments disassembled; however, the vacuoles did not rupture until after plasma membrane integrity was lost. Instead of facilitating rupture, the simplification of vacuole structure might play a role in the retrieval of membrane components needed for defense-related cell death.

关键词： Actin filaments defense-related cell death Erwiniacarotovora tobacco BY-2 cells vacuoles

Regulation of Vascular Development by CLE Peptide-receptor Systems

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Journal of Integrative Plant Biology 2010年第1期52卷 8-16页

作者： Yuki hirakawa Yuki Kondo Hiroo Fukuda Department of Biological Sciences Graduate School of ScienceThe University of Tokyo

Cell division and differentiation of stem cells are controlled by non- cell-autonomous signals in higher organisms. The plant vascular meristem is a stem-cell tissue comprising procambial cells that produce xylem cells on one side and phloem cells on the other side. Recent studies have revealed that TDIF （tracheary element differentiation inhibitory factor）/CLE41/CLE44 peptide signal controls the procambial cell fate in a non-cell-autonomous manner. TDIF produced in and secreted from phloem cells is perceived by TDR/PXY, a leucine-rich repeat receptor kinase located in the plasma membrane of procambial cells. This signal suppresses xylem cell differentiation of procambial cells and promotes their proliferation. In addition to TDIF, some other CLE peptides play roles in vascular development. Here, we summarize recent advances in CLE signaling governing vascular development.

关键词： TDIF Regulation of Vascular Development by CLE Peptide-receptor Systems

Effect of Aging Treatment on Bending Workability of Dual Phase High Strength Stainless Steel

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Effect of Aging Treatment on Bending Workability of Dual Pha...

More efficient induction of genotoxicity by high-LET Fe-particle radiation than low-LET X-ray radiation at low doses

第十届中国钢铁年会暨第六届宝钢学术年会

作者： Naoki hirakawa Stainless Steel & High Alloy R&D Dept.Steel & Technology Dev.Lab. Nisshin Steel Co. Ltd.

A ferrite-martensite dual-phase stainless steel(0.07%C-2%Ni-16.3%Cr alloy) having good formability has been developed. However, when this steel is bent toward transverse direction, its bending workability is inferior to when bent toward longitudinal direction, because this steel has anisotropy of bending workability and ferrite-martensite lamellar structure formed by rolling one way. It was confirmed that the anisotropy of bending workability was improved by aging treatment in this investigation. This study was carried out to examine the effect of the aging treatment at various temperatures ranging from 250℃ to 450℃ for 14h. As a result, bend tests showed that the bending workability had been improved by the aging treatment at temperatures between 300℃ for 9h and 400℃ for 9h while maintaining strength. In the case of an aging treatment at temperature between 300℃ for 9h and 400℃ for 9h, the Cottrell atmosphere is formed by carbon in ferrite phase, therefore the hardness of ferrite phase increases. On the other hand, the hardness of martensitic phase decreases by tempering. This fact shows that an appropriate aging treatment decreases the strength difference between ferrite phase and martensitic phase. The decreasing of the strength difference reduces concentration of deformation in ferrite phase. The improvement of bending workability is attributed mainly to the decreasing of the strength difference between ferrite and martensite.

关键词： dual phase stainless steel high strength workability aging

来源： cnki会议评论

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Radiation Medicine and Protection 2023年第1期4卷 11-18页

作者： Bing Wang Takanori Katsube Kaoru Tanaka Yasuharu Ninomiya Hirokazu hirakawa Cuihua Liu Kouichi Maruyama Masahiro Murakami Tetsuo Nakajima Akira Fujimori Mitsuru Nenoi National Institutes for Quantum Science and Technology Chiba263-8555Japan

Objective:To understand differential effects on induction of genotoxicity and genomic instability(GI)by high-LET particle radiation and low-LET photon radiation,based on ground-based experiments using total body irradiation(TBI)of mice with Fe-particle radiation and X-ray radiation.Methods:TBI was delivered to C57BL/6J Jms strain female mice of 8 weeks old at a dose ranging from 0.1 to 3.0 Gy of Fe-particle radiation or at a dose ranging from 0.1 to 5.0 Gy of X-ray radiation.Induction of genotoxicity and GI by TBI was determined respectively at 1 and 2 months after exposure using frequency of micronuclei in bone marrow erythrocytes as the endpoint.Inhibition of bone marrow cell proliferation by TBI was measured as reduced erythropoiesis.Physiological conditions were also investigated.Results:TBI,regardless of the type of radiation,caused statistically significant increase in genotoxicity at 1 month after exposure,but did not induce GI at 2 months after exposure even at higher doses(>1.0 Gy).The doseresponse curve for the frequency of micronucleated polychromatic erythrocytes induced by Fe-particle radiation and X-ray radiation was y=0.7798 t 1.7889x–0.5978x^(2)(R^(2)=0.8109)and y=0.7421 t 1.3792x–0.2588 x^(2)(R^(2)=0.8081),respectively.The dose-response curve for the frequency of micronucleated normochromatic erythrocytes induced by Fe-particle radiation and X-ray radiation was y=0.7191 t 1.4545x–0.4978x^(2)(R^(2)=0.7047)and y=0.658 t 1.344x–0.2531x^(2)(R^(2)=0.7853),respectively.In general,high-LET Fe-particle radiation was more efficient in inducing genotoxicity than low-LET X-ray radiation at lower doses(<0.5 Gy).Conclusions:These results further confirm that exposure to TBI,even at higher doses and regardless the type of radiation,does not induce GI in C57BL/6J strain mice measured as increased micronuclei in bone marrow erythrocytes.These findings indicate that radiation-induced GI is mouse strain dependent and suggest that more comprehensive studies should be done to explore the late health consequences fro

关键词： Fe-particle radiation Genotoxicity Genomic instability Micronucleated erythrocyte C57BL/6J mice

Patellar dislocation following distal femoral replacement after extraarticular knee resection for bone sarcoma:A case report

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World Journal of Clinical Cases 2022年第11期10卷 3561-3572页

作者： Yuta Kubota Kazuhiro Tanaka Masashi hirakawa Tatsuya Iwasaki Masanori Kawano Ichiro Itonaga Hiroshi Tsumura Orthopaedic Surgery Oita UniversityYufu City 879-5593OitaJapan

BACKGROUND For the treatment of bone sarcoma in the distal femur,wide-margin resection and knee reconstruction with tumor endoprosthesis are standard therapies.Extraarticular knee resection is required in cases of tumor invasion of the knee joint;however,the incidence of complications,such as aseptic loosening,prosthesis infection,and implant failure,is higher than that following intra-articular knee resection.To the best of our knowledge,there are three reports of patellar dislocations after replacement of a tumor endoprosthesis.CASE SUMMARY A 36-year-old man with no significant past medical history was admitted to our institution with continuous pain in his left knee for 4 mo.An open biopsy was performed,and the patient was diagnosed with a left distal femoral malignant bone tumor.Extra-articular knee resection and knee reconstruction with a tumor endoprosthesis were performed.Although the alignment of the tumor prosthesis was acceptable,knee instability was noticed postoperatively.The axial radiographic view of the patellar and computed tomography showed lateral patellar dislocation at 4 wk postoperatively.The patient had to undergo a lateral release and proximal realignment.He could perform his daily activities at 9 mo postoperatively.Radiography revealed no patellar re-dislocation.CONCLUSION Proximal realignment may be considered during primary surgery if there is an imbalance in the forces controlling the patellar tracking.

关键词： Bone tumor Distal femoral replacement Lateral release Patellar dislocation Proximal realignment Case report

A 92-year-old man with retropharyngeal hematoma caused by an injury of the anterior longitudinal ligament

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Chinese Journal of Traumatology 2010年第2期13卷 120-122页

作者： Seiji Morita Shinichi lizuka Haruna hirakawa Shigeo Higami Takeshi Yamagiwa Sadaki Inokuchi Department of Emergency and Critical Care Medicine Tokai University School of Medicine 143 Shimokasuya Isehara-City Kanagawa 2591193 Japan

Abstract：Traumatic retropharyngeal hematoma is a rare condition and may be lethal in some cases.In patients with this condition, the absence of a vertebral fracture or a major vascular injury is extremely rare.We present the case of a 92-year-old man who hit his forehead by slipping on the floor in his house.He had no symptoms at the time; however, he experienced throat pain and dyspnea at 6 hours after the injury.On arrival, he complained of severe dyspnea; therefore, an emergency endotracheal intubation was performed.A lateral neck roentgenogram after intubation showed dilatation of the retropharyngeal and retrotracheal space and no evidence of a cervical vertebral fracture.Cer-vical computed tomography (CT) with contrast medium re-vealed a massive hematoma extending from the retropharyngeal to the superior mediastinal space but no evidence of contrast medium extravasation or a vertebral fracture.However, sagittal magnetic resonance imaging (MRI) revealed an anterior longitudinal ligament (C levels)injury.We determined that the cause of the hematoma was an anterior longitudinal ligament injury and a minor vascu-lar injury around the injured ligament.Therefore, we recom-mend that patients with retropharyngeal hematoma undergo sagittal cervical MRI when roentgehography and CT reveal no evidence of injury。

关键词：血管损伤血肿韧带男子呼吸困难气管插管磁共振成像断层扫描