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雷暴冲击风模拟及其荷载的风洞试验研究 被引量:24
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作者 赵杨 曹曙阳 +2 位作者 Yukio Tamura 段忠东 S. ozono 《振动与冲击》 EI CSCD 北大核心 2009年第4期1-3,9,共4页
为了研究在突变气流作用下结构的空气动力特性,介绍了利用主动控制风洞模拟突变气流的试验研究。首先通过该风洞模拟出了雷暴冲击风阵风剖面;然后,采用"阶跃流法"模拟了风速突变的时程;最后将高层结构模型置于该突变气流中,... 为了研究在突变气流作用下结构的空气动力特性,介绍了利用主动控制风洞模拟突变气流的试验研究。首先通过该风洞模拟出了雷暴冲击风阵风剖面;然后,采用"阶跃流法"模拟了风速突变的时程;最后将高层结构模型置于该突变气流中,观测在特殊气流中结构表面风压以及结构空气动力学参数的变化特征。试验结果表明,利用主动控制风洞模拟出的雷暴冲击风阵风剖面同理论的相似性达到90%以上,突变气流会使高层结构整体产生较大的非定常升力,并且在结构表面产生较大的非定常风压。 展开更多
关键词 雷暴冲击风 阶跃流法 主动控制风洞 风洞试验
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多风扇主动控制风洞类平板断面抖振力识别研究 被引量:8
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作者 潘韬 赵林 +2 位作者 曹曙阳 葛耀君 S.ozono 《振动与冲击》 EI CSCD 北大核心 2010年第6期178-183,230,共7页
针对目前一般的大气边界层物理风洞采用被动格栅产生的紊流脉动风场功率谱密度能量分布难以调整以及积分尺度过小的问题,借助于主动控制方法善于改变来流功率谱及积分尺度的特点,利用日本宫崎大学多风扇主动控制风洞调试出多种宽带紊流... 针对目前一般的大气边界层物理风洞采用被动格栅产生的紊流脉动风场功率谱密度能量分布难以调整以及积分尺度过小的问题,借助于主动控制方法善于改变来流功率谱及积分尺度的特点,利用日本宫崎大学多风扇主动控制风洞调试出多种宽带紊流风场和谐波脉动风场,采用脉动风速和气动力同步采集监控装置,使用测量稳定性好、精度较高的节段模型高频天平测力方法识别类平板模型的抖振力,对影响模型抖振力的主要参数(积分尺度、紊流度、攻角等)进行分析。 展开更多
关键词 多风扇主动控制 VonKarman谱 谐波脉动风场 类平板
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几种非平稳分析方法对非平稳风力时程的比较分析 被引量:7
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作者 赵杨 曹曙阳 +3 位作者 武岳 Tamura Yukio 段忠东 ozono S. 《土木工程学报》 EI CSCD 北大核心 2011年第9期51-57,共7页
非平稳信号的分析方法是信号分析领域中的一个重要问题。本文以风洞试验获得的非平稳风压信号和升力系数信号为研究对象,分别采用短时傅里叶变换、Wigner-Ville分布,小波变换方法和Hilbert-Huang变换(HHT)方法对信号进行时频分析。分析... 非平稳信号的分析方法是信号分析领域中的一个重要问题。本文以风洞试验获得的非平稳风压信号和升力系数信号为研究对象,分别采用短时傅里叶变换、Wigner-Ville分布,小波变换方法和Hilbert-Huang变换(HHT)方法对信号进行时频分析。分析结果表明,由于短时傅里叶变换、Wigner-Ville分布,小波变换方法都是基于傅里叶变换,因此,得到的频谱特性都大致相同,只是在分析的精细程度上有所差异;HHT方法可以获得有意义的瞬时频率,从而给出频率随时间变化的精确表达,信号最终被表示为时频平面上的能量分布,成为Hilbert谱,该方法适用于分析生活中普遍存在的大量频率随时间变化的非线性、非平稳信号,可将复杂的信号直接分离成从高频到低频的若干阶固有模态函数。另一方面,无论用哪一种分析方法都可以看出,风速和风压信号的能量大多分布在低频部分,高频部分所占比例很少,而升力信号的能量大多分布在高频部分,低频部分所占比例很少。本文采用HHT方法提取起控制作用的信号主成分。 展开更多
关键词 非平稳信号 希尔伯特-黄 短时傅里叶变换 Wigner-Vill分布 小波变换
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利用HHT方法对非平稳风力的时频分析 被引量:7
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作者 赵杨 武岳 +3 位作者 曹曙阳 段忠东 Yukio Tamura S. ozono 《振动与冲击》 EI CSCD 北大核心 2011年第2期5-9,14,共6页
非平稳信号的分析方法是信号分析领域中的一个重要问题。以风洞试验获得的非平稳风压信号和升力系数信号为研究对象,采用HHT方法对信号进行时频分析。HHT(Hilbert-Huang transform)方法可以获得有意义的瞬时频率,从而给出频率随时间变... 非平稳信号的分析方法是信号分析领域中的一个重要问题。以风洞试验获得的非平稳风压信号和升力系数信号为研究对象,采用HHT方法对信号进行时频分析。HHT(Hilbert-Huang transform)方法可以获得有意义的瞬时频率,从而给出频率随时间变化的精确表达;信号最终被表示为时频平面上的能量分布,成为Hilbert谱;该方法适用于分析生活中普遍存在的大量频率随时间变化的非线性、非平稳信号,可将复杂的信号直接分离成从高频到低频的若干阶固有模态函数。分析结果虽然没有表现出明显的频谱分布特性,但与以往HHT分析结果提取的固有模态函数不同,如果对该试验获得的非平稳信号提取的固有模态是低频部分的残余信号,忽略其他高频信号,则风压时程和升力系数时程的残余信号曲线就可以分别回归为一个线性函数和一个正弦函数。这也说明,该非平稳信号的主成分仍然是由平稳信号组成的,可以用分析平稳信号的方法进行时程分析。 展开更多
关键词 非平稳信号 希尔伯特-黄 经验模态分解法 固有模态函数 时程分析
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主动来流条件类平板断面气动力荷载效应分析 被引量:3
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作者 潘韬 赵林 +2 位作者 曹曙阳 葛耀君 S.ozono 《实验流体力学》 EI CAS CSCD 北大核心 2010年第6期32-37,56,共7页
利用日本宫崎大学11×9多风扇主动控制来流风洞和高精度动态天平测力设备,测量了类平板断面在正弦风波来流条件三分量气动力荷载,比较了不同来流平均风速、波动幅值、脉动频率和积分尺度等参数条件下类平板断面荷载效应。报导并证... 利用日本宫崎大学11×9多风扇主动控制来流风洞和高精度动态天平测力设备,测量了类平板断面在正弦风波来流条件三分量气动力荷载,比较了不同来流平均风速、波动幅值、脉动频率和积分尺度等参数条件下类平板断面荷载效应。报导并证实了大气边界层物理风洞固定壁面边界反射效应所产生的倍频放大效应;在获得并验证正弦风波加载离散频率荷载效应可线性迭加的有效频段区间内,初步比较了来流积分尺度和风速湍流度效应对于气动荷载效应的影响,阐明典型节段模型风洞试验结果与传统随机抖振气动力理论的差异。 展开更多
关键词 多风扇主动风洞 正弦来流 类平板断面 气动力荷载
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Multiple intrahepatic artery aneurysms during the treatment for IgG4-related sclerosing cholangitis:A case report
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作者 Hotaka Tamura Yoshinori ozono +5 位作者 Keisuke Uchida Naomi Uchiyama Hiroshi Hatada Souichiro Ogawa Hisayoshi Iwakiri Hiroshi Kawakami 《World Journal of Hepatology》 2024年第12期1505-1514,共10页
BACKGROUND The purpose of this case report is to describe a case of multiple intrahepatic artery aneurysms during treatment for IgG4-related sclerosing cholangitis(IgG4-SC)and to provide information for daily practice... BACKGROUND The purpose of this case report is to describe a case of multiple intrahepatic artery aneurysms during treatment for IgG4-related sclerosing cholangitis(IgG4-SC)and to provide information for daily practice.CASE SUMMARY A 64-year-old Japanese woman was diagnosed with IgG4-SC five years prior and was receiving maintenance treatment with prednisolone 7.5-10 mg/day.She developed abdominal pain and a sudden onset of black stool and was admitted to our hospital.Abdominal contrast-enhanced computed tomography(CT)and ultra-sonography(US)revealed multiple intrahepatic artery aneurysms that developed during the treatment for IgG4-SC.Emergency transarterial embolization for mu-ltiple hepatic artery aneurysms was performed.Hepatic artery aneurysms disappeared on contrast-enhanced CT and US,the progression of anemia ceased,and the melena resolved.Thus,hemostasis was achieved.CONCLUSION Hepatic artery aneurysms should be considered poor prognostic complications of IgG4-SC. 展开更多
关键词 Hepatic artery aneurysm PSEUDOANEURYSM IgG4-related sclerosing cholangitis EMBOLIZATION MELENA Atherosclerosis Case report
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Linked Data-based Slide Repository: The Episodic Slide Retrieval Using the Episodic Keyword Networks
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作者 Tomohiro Iwasa Yudai Kato +2 位作者 Shun Shiramatsu Tadaehika ozono Toramatsu Shintani 《Journal of Control Science and Engineering》 2016年第1期36-49,共14页
This paper focuses on developing a system that allows presentation authors to effectively retrieve presentation slides for reuse from a large volume of existing presentation materials. We assume episodic memories of t... This paper focuses on developing a system that allows presentation authors to effectively retrieve presentation slides for reuse from a large volume of existing presentation materials. We assume episodic memories of the authors can be used as contextual keywords in query expressions to efficiently dig out the expected slides for reuse rather than using only the part-of-slide-descriptions-based keyword queries. As a system, a new slide repository is proposed, composed of slide material collections, slide content data and pieces of information from authors' episodic memories related to each slide and presentation together with a slide retrieval application enabling authors to use the episodic memories as part of queries. The result of our experiment shows that the episodic memory-used queries can give more discoverability than the keyword-based queries. Additionally, an improvement model is discussed on the slide retrieval for further slide-finding efficiency by expanding the episodic memories model in the repository taking in the links with the author-and-slide-related data and events having been post on the private and social media sites. 展开更多
关键词 Slide Retrieval Linked Data-based Slide Repository Episodic Keyword Networks Linked Data episodic memories social media life event.
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成对交叉辊(PC)轧机在热轧机和冷轧机中的推广应用
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作者 Hiroshi Aratani Ryuichi ozono +1 位作者 Tsuneo Nakano 赵立新 《一重技术》 1994年第2期166-171,共6页
装有在线轧辊磨头的成对交叉辊(PC)热轧机改善了板带凸度、板形控制及实现了自由规程轧制。在中板轧机上采用了PC技术后也改善了产品质量、减少了轧制道次、提高了生产率、降低了板坯温降和能源消耗。使用在冷轧机上时的预期效果包括提... 装有在线轧辊磨头的成对交叉辊(PC)热轧机改善了板带凸度、板形控制及实现了自由规程轧制。在中板轧机上采用了PC技术后也改善了产品质量、减少了轧制道次、提高了生产率、降低了板坯温降和能源消耗。使用在冷轧机上时的预期效果包括提高压下率和改善板型(边部减薄)。 展开更多
关键词 热轧机 冷轧机 成对交叉辊
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Monocyte-derived fibrocytes elimination had little contribution on liver fibrosis
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作者 Yoshinori ozono Kotaro Shide +12 位作者 Fumiyo Toyoshima Yuuka Takaishi Mai Tsuchimochi Ayako Kamiunten Takuro Kameda Kenichi Nakamura Tadashi Miike Kazunori Kusumotoa Hisayoshi Iwakiri Satoru Hasuikea Kenji Nagata Akira Sawaguchi Kazuya Shimoda 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第4期348-353,共6页
Background:Monocyte-derived fibrocytes play an important role in the progression of fibrosis in the skin,lungs,heart and kidney.However,the contribution of fibrocytes to liver fibrosis is unclear.The aim of this study... Background:Monocyte-derived fibrocytes play an important role in the progression of fibrosis in the skin,lungs,heart and kidney.However,the contribution of fibrocytes to liver fibrosis is unclear.The aim of this study was to investigate whether fibrocytes contributed to fibrosis progression in the livers of carbon tetrachloride(CCl 4)-treated mice.Methods:C57BL/6J mice were divided into 4 groups:normal control group,CCl 4-treated group,CCl 4+control liposome-treated group,and CCl 4+clodronate liposome-treated group.For the elimination of systemic monocyte and monocyte-derived fibrocyte,one group was treated with clodronate liposome,and another group with control liposome as a control.After 4 weeks of treatment,hepatic mononuclear cells were subjected to immunofluorescent(IF)staining and fluorescence-activated cell sorter(FACS)analysis to detect fibrocytes.Measurement of collagen-positive Sirius red stained area and collagen-I mRNA expression in the liver were performed to evaluate the degree of liver fibrosis quantitatively.Results:In the liver of the CCl 4-treated and CCl 4+control liposome-treated groups,the number of fibrocytes,the area positive for Sirius red staining and collagen-I mRNA expression significantly increased compared with those in the normal control group.In the liver of the CCl 4+clodronate liposome-treated group,few fibrocytes was observed as in the normal control group,but Sirius red staining positive area and collagen-I mRNA expression were increased and equivalent to the CCl 4-treated and CCl 4+control liposome-treated groups.Conclusion:Monocyte-derived fibrocytes play a minimal role in CCl 4-induced liver fibrosis.Cells other than fibrocytes such as hepatic stellate cells play a central role in liver fibrosis. 展开更多
关键词 FIBROCYTES Liver fibrosis Carbon TETRACHLORIDE CLODRONATE Collagen-I
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Efficacy and safety of sofosbuvir and ledipasvir in Japanese patients aged 75 years or over with hepatitis C genotype 1
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作者 Yoshinori ozono Kenji Nagata +20 位作者 Satoru Hasuike Hisayoshi Iwakiri Kenichi Nakamura Mai Tsuchimochi Yuri Yamada Yuka Takaishi Mitsue Sueta Tadashi Miike Yoshihiro Tahara Shojiro Yamamoto Kotaro Shide Tomonori Hidaka Yoko Kubuki Kazunori Kusumoto Toshimasa Ochiai Junya Kato Naoto Komada Shuichi Hirono Kazuo Kuroki Masafumi Shigehira Kazuya Shimoda 《World Journal of Hepatology》 CAS 2017年第36期1340-1345,共6页
AIM To evaluate the efficacy and safety of a regimen containing sofosbuvir(SOF) and ledipasvir(LDV) in Japanese patients aged ≥ 75 years with hepatitis C genotype 1.METHODS This multicenter, retrospective study consi... AIM To evaluate the efficacy and safety of a regimen containing sofosbuvir(SOF) and ledipasvir(LDV) in Japanese patients aged ≥ 75 years with hepatitis C genotype 1.METHODS This multicenter, retrospective study consisted of 246 Japanese patients with HCV genotype 1 at nine centers in Miyazaki prefecture in Japan. Demographic, clinical, virological, and adverse effects(AE)-related data obtained during and after SOF/LDV therapy were collected from medical records. These patients were divided into two groups, younger(aged < 75 years) and elderly(aged ≥ 75 years). Virological data and AEs were analyzed by age group.RESULTS The sustained virological response(SVR) rates at 12 wk after treatment were 99.2%, 99.4%, and 98.7% in the overall population and in patients aged < 75 and ≥ 75 years, respectively. Common AEs during therapy were headache, pruritus, constipation, and insomnia. These occurred in fewer than 10% of patients, and their incidence was not significantly different between the younger and elderly groups. Two patients discontinued treatment, one due to a skin eruption and the other due to cerebral bleeding. CONCLUSION Compared with younger patients, elderly patients had a similar virological response and tolerance to SOF/LDV therapy. 展开更多
关键词 Chronic hepatitis C Sofosbuvir Ledipasvir Sustained virological response Direct acting antivirals
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Web Block Extraction System Based on Client-Side Imaging for Clickable Image Map
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作者 Hiroyuki Sano Shun Shiramatsu Tadachika ozono Toramatsu Shintani 《通讯和计算机(中英文版)》 2013年第6期815-822,共8页
关键词 提取系统 客户端 网页 地图 成像 WEB页面 WEB信息 Web模块
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组织非特异性碱性磷酸酶基因的F310L和T1559del常见突变与日本患者的磷酸酯酶过少症天生表现型间有一定的相关性
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作者 Michigami T. Uchihashi T. +2 位作者 Suzuki A. K. ozono 王经纬 《世界核心医学期刊文摘(儿科学分册)》 2005年第9期43-44,共2页
A total of 22 Japanese patients with hypophosphatasia were included in a study analysing the relationship between mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene and the severity of the phenotyp... A total of 22 Japanese patients with hypophosphatasia were included in a study analysing the relationship between mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene and the severity of the phenotype in Japanese patients with hypophosphatasia. The enzymatic activity of some of the identified mutant TNSALP proteins was also examined using corresponding expression vectors. Eighteen mutations, including 6 novel ones, were identified in the patients. Among them,the common mutations were F310L and T1559del. Of note, five patients with F310L mutation in one of the alleles exhibited a relatively mild phenotype without respiratory complications despite its perinatal onset. In contrast, the T1559del mutation is associated with perinatal lethal and infantile forms when not found in patients with the F310L mutation. The genotype-phenotype relationship was, to some extent, consistent with the enzymatic activity of the mutant ALP proteins; mutations K207E and G409C found in a surviving case of infantile hypophosphatasia, as well as F310L, retained some residual activities, whereas T1559del caused a complete loss of activity. Conclusion: In Japanese patients, the common mutations F310L and T1559del are associated with the relatively mild and lethal forms of hypophosphatasia, respectively. Our results may enhance the importance of genotyping patients with hypophosphatasia to predict their prognosis. 展开更多
关键词 F310L T1559del 磷酸酯酶 表现型 基因突变 围生期 蛋白酶活性 碱性磷酸酶 呼吸道并发症 胎儿期
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Experimental Study of the Response of Transonic Diffuser Flow to a Piezoceramic Actuator at Diffuser Throat
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作者 Minoru Yaga Yusuke Uechi +2 位作者 Hiroaki ozono Masaaki Ishikawa Isao Teruya 《Open Journal of Fluid Dynamics》 2013年第2期14-21,共8页
An experimental study of the response of a piezoceramic actuator set at the throat to a transonic diffuser is carried out by measuring wall static pressure fluctuations and by visualizing the flow field using schliere... An experimental study of the response of a piezoceramic actuator set at the throat to a transonic diffuser is carried out by measuring wall static pressure fluctuations and by visualizing the flow field using schlieren technique. The visualized flow fields are captured with a digital still camera and a digital high speed video camera. The piezo ceramic actuator is attached at the throat of the diffuser and driven by sinusoidal amplified voltage signals. The diffuser used in this experiment is circular arc half nozzle with the height h* and width w of 3 mm and 25 mm, respectively. The blockage factor of the piezoceramic actuator to the diffuser throat is 9.2% assuring the effect of change in the throat area rather than the boundary layer disturbances. The piezoceramic actuator is driven at the frequency of 100 Hz, 200 Hz, and 300 Hz and its amplitude is about 1 mm. It is found that the wall static pressure fluctuations and the behavior of the shock wave clearly correspond to the vibration of the piezo ceramic actuator for all the frequency ranges whereas the averaged shock position remains almost unchanged. All the results mentioned above suggest that driving the piezo ceramic actuator at the diffuser throat can be one of the promising techniques to control unsteady transonic diffuser flow. 展开更多
关键词 COMPRESSIBLE Flow Shock Wave TRANSONIC DIFFUSER PIEZOCERAMIC ACTUATOR THROAT
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