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Failure Envelopes of Single-Plate Rigid Helical Anchors for Floating Offshore Wind Turbine

China Ocean Engineering 2023年第6期37卷 1000-1010页

作者： chen hong-zhen WANG Le TIAN Ying-hui ZHANG Chun-hui SHEN Zhi-chao LIU Meng-meng State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Infrastructure Engineering Faculty of Engineering and Information Technology The University of MelbourneVictoria 3010Australia School of Civil Engineering Hebei University of Science and TechnologyShijiazhuang 050018China Hebei Technological Innovation Center of Disaster Prevention and Mitigation Engineering of Geotechnical and Structural System Shijiazhuang 050018China School of Marine Science and Engineering South China University of TechnologyGuangzhou 511442China Institute of Ocean Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China

Helical anchor is a kind of novel foundation for floating offshore wind turbines,which should be subjected to combined tensile loading caused by wind,wave and ***,the research about the capacity of helical anchor was mainly examined under uniaxial loading and scarcely explored under combined *** this study,three-dimensional finite element limit analysis is adopted to assess the bearing capacities of single-plate rigid helical anchors with different ratios of helix to shaft diameter,D_(H)/D_(S) and embedment ratios L/D_(S).Result shows that the vertical,horizontal and moment bearing capacities increase with increasing D_(H)/D_(S) and L/D_(S).The normalized V-H failure envelopes expands with increasing L/D_(S),while the normalized V-M failure envelopes tend to contract with the increase of D_(H)/D_(S).With increasing D_(H)/D_(S) or decreasing L/D_(S),the normalized H-M failure envelopes expand when the horizontal and moment loading act in the same direction and contract when they act in the opposite *** effect of D_(H)/D_(S) and L/D_(S) on the shape of H-M failure envelope become insignificant when L/D_(S)≥4.A series of failure mechanisms under different loading conditions were observed and can be used to explain the ***,a series of approximate expressions were proposed to fit the uniaxial bearing capacities and the failure envelopes.

关键词： helical anchors bearing capacity failure envelope clay

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Bending-Rays Imaging Based on Genetic Algorithm

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 585-588页

作者： Foundation item: Liu Huai lin, Liu hong, chen Shu zhen College of Electronic Information, Wuhan University, Wuhan 430072, China College of Electronic Information Wuhan University Wuhan China

Basic principle of bending rays imaging is discussed briefly and an improved genetic algorithm is presented to settle the converse computation of bending rays imaging. Compared with other algorithms, this one improv... 详细信息

关键词： genetic algorithm bending rays incomplete projection travel time

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Study on Prediction of Summer Rainstorm Induced by Southwest Vortex in Guizhou Province

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Meteorological and Environmental Research 2011年第8期2卷 9-13页

作者： WANG Xing-ju chen zhen-hong YE Bang Lanzhou University Lanzhou 730020China Key Laboratory for Mountain Climate and Resources in Guizhou Province Guiyang 550002China Anshun Weather Bureau in Guizhou Province Anshun 561000China

[Objective] The aim was to study the prediction of summer rainstorm induced by southwest vortex.[Method] Based on 2.5°×2.5° re-analysis data in four time points a day from June to August during 1971-2008 at 700 hPa in northern hemisphere provided by NECP,rainstorm and southwest vortex from June to August in Guizhou Province were studied systematically,and the forecast data of rainstorm induced by southest vortex was obtained.[Result] Southwest vortex was one of major systems influencing rainstorm in flood season(from June to August),especially in June and July;the occurrence of this kind of rainstorm was closely related to the moving path of southwest vortex,activity of cold air,environmental flow field at 500 hPa,shear line at 850 hPa,southwest jet,position of subtropical high ridge,water vapour conditions,vorticity field,*** the basis of factual data,objective forecast system was established and verified by means of similar method and physical *** results showed that it was rational to choose upper trough,southwest vortex,conditions of vertical movement,southwest jet,water vapour conditions,*** forecast factors;when the center of southwest vortex was located in major key area(100°-105° E,25°-35° N),and secondary key area(105°-108° E,25°-35° N),regional rainstorm occurred most easily,especially in major key area with high frequency of rainstorm.[Conclusion] The study could provide references for the improvement of prediction level of rainstorm induced by southwest vortex,disaster prevention and reduction.

关键词： Southwest vortex Summer rainstorm Prediction Guizhou Province China

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Fetal reduction by bipolar cord coagulation in managing complicated monochorionic multiple pregnancies： preliminary experience in China

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Chinese Medical Journal 2010年第5期123卷 549-554页

作者： HE Zhi-ming FANG Qun YANG Yong-zhong LUO Yan-min chen Jun-hong chen Yong-zhen ZHOU Yi chen Min-ling Fetal Medicine Center First Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong 510080 China

Background Monochorionic multiple pregnancies （MMPs） are associated with higher rates of perinatal morbidity and mortality caused by interfetal vascular anastomoses in the monochorionic placenta, which can lead to fetal health interactions. In some circumstances, selective feticide of the affected fetus is necessary to save the healthy co-twin. We evaluated the effects and safety of our initial experiences using bipolar cord coagulation for the management of complicated MMPs. Methods Using ultrasound-guided bipolar cord coagulation, we performed selective feticide on 14 complicated MMPs （5 with twin-twin transfusion syndrome, 4 with acardia, 3 with discordant structural anomalies, and 2 with severe selective intrauterine growth restriction）. One patient with monochorionic triplets received the procedure twice to terminate 2 affected fetuses for different JndJcatJons. Data regarding the operations, complications and neonatal outcomes were analyzed. Results Cord occlusions were successfully performed in 13/14 （93%） cases. The failure happened in an acardiac fetus and the pregnancy was terminated by induction. The included cases delivered at a mean gestational age of 35.4 weeks with a perinatal survival rate of 11/13 （85%）. Three operation-related complications occurred （21%）, including membrane rupture of the terminated sac （1 case）, preterm labor at 28 weeks gestation （1 case）, and chorioamniotic membrane separation （1 case）. Amnioinfusion was indicated in 11 procedures to expand the target sacs for entering the trocar and obtaining sufficient working space. However, in all 4 cases of acardia, the acardiac sacs showed extreme oligohydramnios and could not be well expanded by infusion; thus, the trocar had to be inserted from the sac of the preserved co-twin. Conclusions The application of bipolar cord coagulation in complicated MMPs is safe and improves the prognosis. Amnioinfusion is useful in helping to expand the target sac when the working space is limited.

关键词： pregnancy reduction, multifetal," monochorionic cord coagulation," twin-twin transfusion syndrome," acardia

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数字全息术用于光学元件表面缺陷形貌测量

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光学精密工程 2017年第3期25卷 576-583页

作者：陈竹姜宏振刘旭陈波中国工程物理研究院激光聚变研究中心四川绵阳621900

利用像面数字全息显微术对光学元件表面缺陷的三维形貌测量进行了理论及实验研究。设计并搭建了相应光路系统记录全息图,采用角谱算法数值重建物光场,通过相位修正消除了系统误差引入的波前畸变,获得了经过待测光学元件表面缺陷调制的... 详细信息

利用像面数字全息显微术对光学元件表面缺陷的三维形貌测量进行了理论及实验研究。设计并搭建了相应光路系统记录全息图,采用角谱算法数值重建物光场,通过相位修正消除了系统误差引入的波前畸变,获得了经过待测光学元件表面缺陷调制的物光相位分布,并根据建立的相位分布与表面缺陷面形的关系模型计算得到缺陷三维形貌。实验以多个划痕和麻点等常见表面缺陷作为测量对象,分别获得了它们的三维形貌,以其中一条实际宽度为35μm、深度为270nm的划痕为例,测量得到该划痕的宽度为35.21μm,平均深度为267.6nm,与真实值相比,横向测量误差为0.6%,纵向测量误差为0.9%。实验结果证实该测量方法是有效、可靠的,能够准确测量光学元件表面缺陷的三维形貌,因而有助于判断光学元件损伤程度以及分析缺陷对系统波前的影响,对保障高功率激光装置的安全正常运行有重要意义。

关键词：数字全息显微术三维形貌测量光学元件表面缺陷相位修正

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冷却制度对铁素体基Ti-Mo微合金钢超细碳化物析出行为的影响

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材料工程 2014年第10期42卷 47-52页

作者：孙超凡蔡庆伍陈振华陈宏振北京科技大学高效轧制国家工程研究中心北京100083

采用SEM、TEM和SAXS研究了轧后γ→α相变过程以及γ→α相变后冷却速率对（Tix，Mo1-x）C粒子析出行为的影响。结果表明：在γ→α相变温度范围内采用较快的冷却速率可以使相间析出的（Tix，Mo1-x）C粒子尺寸更细小，分布更均匀，这些... 详细信息

采用SEM、TEM和SAXS研究了轧后γ→α相变过程以及γ→α相变后冷却速率对（Tix，Mo1-x）C粒子析出行为的影响。结果表明：在γ→α相变温度范围内采用较快的冷却速率可以使相间析出的（Tix，Mo1-x）C粒子尺寸更细小，分布更均匀，这些粒子尺寸多数在1～10nm；γ→α相变完成后缓慢冷却可以使（Tix，Mo1-x）C粒子在α基体中进一步弥散析出，这类弥散析出的粒子形成温度低，尺寸细小均匀。

关键词：冷却制度 Ti-Mo微合金钢相间析出超细碳化物

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Quenching Estimates for Reaction-diffusion Equations with Nonstandard Growth Conditions

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Chinese Quarterly Journal of Mathematics 2013年第3期28卷 408-416页

作者： LIU Bing-chen hong zhen-zhen College of Science China University of Petroleum Qingdao 266580 China

This paper deals with reaction-diffusion equations involving nonstandard growth conditions, subject to homogeneous Neumann boundary conditions. The complete clas- sification is established for simultaneous and non-simultaneous quenching under suitable assumptions on initial data. Moreover, quenching sets and quenching rates are obtained.

关键词： nonstandard growth conditions simultaneous quenching non-simultaneous quenching quenching set quenching rate

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圆柱型油罐SAR图像的多径散射特征和几何参数提取

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红外与毫米波学报 2012年第4期31卷 379-384页

作者：张月婷陈红珍丁赤飚王宏琦中国科学院研究生院北京100190 中国科学院电子学研究所北京100190 中国科学院空间信息处理与应用系统技术重点实验室北京100190 微波成像技术国家重点实验室北京100190

结合多径散射理论和雷达成像原理,针对圆柱型固定顶油罐和浮动顶油罐的SAR图像的多径散射提出了一种预测模型,该预测模型建立了多径散射机制引起的图像上的近似聚焦位置、强度与油罐、雷达相关参数的关系.同时,结合仿真实验和Terra-SAR... 详细信息

结合多径散射理论和雷达成像原理,针对圆柱型固定顶油罐和浮动顶油罐的SAR图像的多径散射提出了一种预测模型,该预测模型建立了多径散射机制引起的图像上的近似聚焦位置、强度与油罐、雷达相关参数的关系.同时,结合仿真实验和Terra-SAR图像验证了该模型的有效性,分析了油罐目标的多径特征,并针对Terra-SAR图像利用基于模型的方法有效提取了油罐目标的几何参数.结果和分析表明,该方法比传统的方法在精度、稳定性上均有所提高.

关键词：油罐 SAR图像多径散射几何参数提取

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Immunoenhancing activity of protopanaxatriol-type ginsenoside-F3 in murine spleen cells

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Acta Pharmacologica Sinica 2004年第12期25卷 105-110页

作者： Jun-li YU, De-qiang DOU2, Xiao-hong chen, hong-zhen YANG, Na GUO2,Gui-fang chenG3 Department of Pharmacology, Institute of Materia Medica, Chinese Academy of MedicalSciences, Peking Union MedicalCollege, Beijing 100050 Departmentof Natural ProductsChemistry, Shenyang Pharmaceutical University, Shenyang 110001, China 2 Department of Pharmacology Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

AIM: To investigate the immunoenhancing activity of ginsenoside-F3 inmurine spleen cells andexplore itsmechanism. METHODS: The enhancing effect of ginsenoside-F3 on murine spleen cell proliferation was studied using [3H] thymidine incorporation assay. Effects of ginsenoside-F3 on the production of type 1 cytokines IL-2, IFN-γ, and type 2 cytokines IL-4 and IL-10 from murine spleen cells were detected by ELISA method. Effects of ginsenoside- F3 on mRNA level of cytokines IL-4, IFN-γ, and transcription factors T-bet and GATA-3 were evaluated by RT- PCR analysis. Effect of ginsenoside-F3 on NF-κB DNA binding activity in murine spleen cells was investigated by electrophoretic mobility shift assays (EMSA). RESULTS: Ginsenoside-F3 at 0.1-100 μmol/L not only promoted the murine spleen cell proliferation, but also increased the production of IL-2 and IFN-γ, while decreased the production of IL-4 and IL-10 from murine spleen cells with the maximal effect at 10 μmol/L. RT-PCR analysis displayed that ginsenoside-F3 enhanced the IFN-γ and T-bet gene expression and decreased IL-4 and GATA-3 gene expression. EMSA experiment showed that ginsenoside-F3 10 μmol/L enhanced the NF-κB DNA binding activity induced by ConA in murine spleen cells. CONCLUSION: Ginsenoside-F3 has immunoenhancing activity by regu- lating production and gene expression of type 1 cytokines and type 2 cytokines in murine spleen cells.

关键词： ginsenoside F3 immunity cytokines transcription factors

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构造抬升对高、低煤阶煤层气藏储集层物性的影响

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石油勘探与开发 2007年第4期34卷 461-464页

作者：陈振宏贾承造宋岩王红岩中国科学院广州地球化学研究所中国石油勘探开发研究院中国石油勘探开发研究院廊坊分院

构造抬升对高、低煤阶煤层气藏储集层物性的影响具有显著差异。低煤阶煤层主要为基质型孔隙,高煤阶煤层主要为裂隙型孔隙。煤岩储集层原地受力分析表明,构造抬升使得基质承受的压力降低。构造抬升模拟实验及煤基质、裂隙渗透率应力敏感... 详细信息

构造抬升对高、低煤阶煤层气藏储集层物性的影响具有显著差异。低煤阶煤层主要为基质型孔隙,高煤阶煤层主要为裂隙型孔隙。煤岩储集层原地受力分析表明,构造抬升使得基质承受的压力降低。构造抬升模拟实验及煤基质、裂隙渗透率应力敏感性实验表明,构造抬升后煤层压力传导加速,割理开启,渗透率变大;基质渗透率比裂隙渗透率的应力敏感性弱。分析认为:构造抬升对高煤阶煤储集层物性影响明显,地层压力降低,割理、裂缝开启,裂隙渗透率显著增强;高煤阶煤层强烈抬升会使其渗透率增大,造成气体大量散失,对煤层气聚集不利;低煤阶煤层储集层物性受构造抬升影响较弱,由于构造抬升,压力降低,煤层气运移速率增大,对煤层气开采有利。

关键词：煤层气高煤阶低煤阶构造抬升储集层物性渗透率

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