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

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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

Specific Expression of a Novel Nodulin GmN479 Gene in the Infected Cells of Soybean (Glycine max) Nodules

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Agricultural Sciences in China 2011年第10期10卷 1512-1524页

作者： CHENG Xian-guo WANG Li WANG He YU Guo-hong BAI You-lu liu meng-meng Key Laboratory of Crop Nutrition and Fertilizer Agriculture of Ministry/Insititute of Agricultural Resource and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Shanxi Normal University College of Life Science Linfen 041004 P.R. China

A novel nodulin gene, GmN479 genomic clone composing of 3 630 nucleotides was isolated from mature soybean nodules using GmN479 cDNA as a probe by subtractive hybridization procedure. GmN479 encodes 170 amino acids with 2.09 kb nucleotides promoter region, and contains two important upstream promoter elements, one is a conserved cis-acting sequence motif 5′-AAAGAT-3′ controlling nodulin gene expression, and the other is typical CAAT boxes. GmN479 gene has a single zinc-finger C2H2 domain YSCAFCQRGFSNAQALLGGHMNIH and a conserved motif, QALGGHMN in the zinc-finger with a short leucine repeat in the LDLELRLGL motif closed to C-terminal. These two conserved motifs share respectively higher identity with those in the floral regulator SUPERMAN gene, indicating that GmN479 may function as a transcriptional regulator, and is a likely candidate for playing a role in nodule-morphogenesis. Blotting data showed that GmN479 is a single copy presenting in the genome of soybean nodule, and its expression profile is similar to that of Lb-a, but it is different from that of ENOD2. GUS staining showed that GmN479 promoter just functions in the infected cells of nodules, indicating that the GmN479 is one of the truly symbiotically induced host genes, and belongs to a late nodulin gene. The expression pattern of GmN479 gene seems to imply that it may be closely related to the development of the nodule. In a sense, it may be a useful marker for identifying the development of the infected cell system in the nodules of soybean.

关键词： nodulin GmN479 promoter soybean nodule transgenic plants

Pre-harvest spraying of oxalic acid improves postharvest quality associated with increase in ascorbic acid and regulation of ethanol fermentation in kiwifruit cv. Bruno during storage

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Journal of Integrative Agriculture 2019年第11期18卷 2514-2520页

作者： Maratab Ali liu meng-meng WANG Zhen-e LI Sheng-e JIANG Tian-jia ZHENG Xiao-lin College of Food Science and Biotechnology Zhejiang Gongshang University

The kiwifruit trees(Actinidia deliciosa ***)were sprayed with 5 mmol L-1 oxalic acid(OA)or water(as control)at 130,137 or 144 d after full-blossom,and then the fruit were harvested at commercial maturity and stored at room temperature(20±1)℃ for 13 *** effect of pre-harvest spraying of OA on postharvest quality of kiwifruit was evaluated during *** OA spraying slowed the increase in soluble solids content(SSC)and decrease in titratable acid(TA),as well as increased contents of ascorbic acid(AsA)and total-AsA accompanied with higher AsA/DHA ratio in kiwifruit during ***,the OA spraying significantly reduced the contents of acetaldehyde and ethanol in kiwifruit,along with significant decrease in activities of enzymes involved in ethanol fermentation metabolism during the later period of storage,which was beneficial to control off-flavor associated with over accumulation of ethanol during *** was suggested that pre-harvest spraying of OA might maintain the postharvest quality of kiwifruit in relation to delay in fruit ripening,AsA maintenance and regulation of ethanol fermentation.

关键词： ethanol metabolism kiwifruit oxalic acid pre-harvest spraying postharvest quality

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新型防沉板基础的地基承载力研究

岩土力学 2016年第11期37卷 3065-3071,3136页

作者：刘润刘孟孟马文冠天津大学水利工程仿真与安全国家重点实验室天津300072 天津大学港口岩土工程技术交通行业重点实验室天津300222

防沉板是水下生产系统中井口、管汇节点、脐带缆等的支撑结构,服役期间需承受V-H荷载空间的强耦合非线性荷载。提出了新型倾斜式裙板防沉板基础型式,倾斜式裙板不仅可以减少海流冲刷对基础下部土体的掏空冲蚀,还可通过调整裙板倾斜角度... 详细信息

防沉板是水下生产系统中井口、管汇节点、脐带缆等的支撑结构,服役期间需承受V-H荷载空间的强耦合非线性荷载。提出了新型倾斜式裙板防沉板基础型式,倾斜式裙板不仅可以减少海流冲刷对基础下部土体的掏空冲蚀,还可通过调整裙板倾斜角度α适应不同工程对承载力的要求,结合工程设计实例研究了新型防沉板的地基承载性能。结果表明,该新型防沉板基础单向极限承载力随土体强度不均匀性指标А的增加呈线性增长,基础与土体接触面属性对水平向承载力的影响远大于对竖向承载力的影响;防沉板基础V-H荷载空间归一化包络线对土体强度不均匀性指标А在0～10范围内具有普适性,在归一化竖向荷载介于0.5-0.8时Hanson公式高估了防沉板基础的承载力。

关键词：水下生产系统防沉板基础倾斜裙板承载特性

带丢包Markov切换线性系统的状态估计问题研究

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电子学报 2016年第3期44卷 646-652页

作者：周卫东刘萌萌哈尔滨工程大学自动化学院黑龙江哈尔滨150001

针对一类带丢包的Markov切换系统,提出一种含有双Markov切换参数的交互式多模型算法.该算法利用一个二态的Markov链对系统是否丢包进行建模,得到双Markov链系统,通过定义乘积集将两个Markov切换参数所对应的模型集进行融合,并给出单个... 详细信息

针对一类带丢包的Markov切换系统,提出一种含有双Markov切换参数的交互式多模型算法.该算法利用一个二态的Markov链对系统是否丢包进行建模,得到双Markov链系统,通过定义乘积集将两个Markov切换参数所对应的模型集进行融合,并给出单个模型集中各模型与乘积集中各模型的对应关系.在此基础上,以交互式多模型算法为框架,采用分层的方法,并利用一种新的最优估计算法对双Markov链系统进行滤波.仿真实验证明了该算法的有效性.

关键词： Markov系统量测丢包双Markov链最优滤波估计交互式多模型算法

多径衰落信道下MIMO OFDM系统的定时同步算法

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北京邮电大学学报 2012年第3期35卷 95-98页

作者：许成谦刘萌萌燕山大学信息科学与工程学院河北秦皇岛066004

提出了一种多径衰落信道下多输入多输出正交频分复用(MIMO OFDM)系统的定时同步算法.算法将恒幅零自相关码作为训练序列,每根发射天线采用修正的循环延迟序列,在接收端分别计算本地序列和接收信号的互相关和接收信号的对称自相关,再将... 详细信息

提出了一种多径衰落信道下多输入多输出正交频分复用(MIMO OFDM)系统的定时同步算法.算法将恒幅零自相关码作为训练序列,每根发射天线采用修正的循环延迟序列,在接收端分别计算本地序列和接收信号的互相关和接收信号的对称自相关,再将二者结合起来以确定定时位置.为了对抗多径信道中第1径不是最强径的情况,还采用了多径后向搜索技术,并利用可变阈值进行判决,以改善同步性能.通过仿真对算法在加性高斯白噪声信道和多径信道下的性能进行了验证和比较.

关键词：多输入多输出正交频分复用定时同步恒幅零自相关多径后向搜索

“由做而知”——近代欧洲一种知识论观念的萌发和生长

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自然辩证法研究 2023年第6期39卷 124-132页

作者：刘萌萌黑龙江大学哲学学院哈尔滨150080

欧洲近代具有一种普遍性的但通常被忽视的知识论线索——“由做而知”。这一知识论观念有一个从古代到中世纪直至近代的漫长的发生学过程,其问题意识出现在古希腊哲学文本中,其思维特性根植于从中世纪至近代的神学思辨、技术实践和炼金... 详细信息

欧洲近代具有一种普遍性的但通常被忽视的知识论线索——“由做而知”。这一知识论观念有一个从古代到中世纪直至近代的漫长的发生学过程,其问题意识出现在古希腊哲学文本中,其思维特性根植于从中世纪至近代的神学思辨、技术实践和炼金术活动中,在近代初期开始成为欧洲知识生产中的核心观念。“由做而知”知识论观念在近代的呈现具有普遍性,影响到培根、笛卡尔、梅森、霍布斯、维柯等,是一个围绕真理论与怀疑论、围绕达到真理的可行方法、围绕人工物与自然物的分界、从自然哲学领域蔓延至人文社会科学领域的具有自身演进逻辑的过程。

关键词：由做而知近代知识论建构论

碳/SiO_2纳米纤维膜基定形相变材料的制备及性能

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功能材料 2014年第18期45卷 18063-18066页

作者：刘盟盟孙桂岩刘倩蔡以兵江南大学生态纺织教育部重点实验室江苏无锡214122

研究首先制得二元脂肪酸低共熔物,然后将用静电纺丝法制备不同SiO2含量的、并对其进行炭化的PAN/SiO2纳米纤维膜作为支撑材料,吸附二元脂肪酸低共熔物制得碳/SiO2纳米纤维膜基定形相变材料(CSNPCM),利用扫描电子显微镜(SEM)、差示扫描... 详细信息

研究首先制得二元脂肪酸低共熔物,然后将用静电纺丝法制备不同SiO2含量的、并对其进行炭化的PAN/SiO2纳米纤维膜作为支撑材料,吸附二元脂肪酸低共熔物制得碳/SiO2纳米纤维膜基定形相变材料(CSNPCM),利用扫描电子显微镜(SEM)、差示扫描量热仪(DSC)等对制备出的定形相变材料的形貌结构和储热性能进行分析和表征。随着SiO2含量的增加,定形相变材料对二元脂肪酸低共熔物的吸附容量有所降低。SEM结果表明,二元脂肪酸低共熔物均匀地包埋、分散在多孔纳米纤维膜的三维网络结构中。DSC测试结果表明,SiO2的加入降低了定形相变材料的相变潜热,对其相变温度无太大影响。

关键词：二元脂肪酸低共熔物静电纺丝定形相变材料物理吸附

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城市规模扩大对区域创新和发展的影响

科学管理研究 2018年第5期36卷 31-33页

作者：刘萌萌上海社会科学院应用经济研究所上海200020

城市规模扩大是一种全球性经济现象,从中等收入国家到高收入国家,大城市人口比重的显著提高是城市规模结构的最重要变化,城市规模扩大、密度增加对区域创新发展具有多方面的积极影响。文从分享、匹配和学习等视角进行了分析,并提出相关... 详细信息

城市规模扩大是一种全球性经济现象,从中等收入国家到高收入国家,大城市人口比重的显著提高是城市规模结构的最重要变化,城市规模扩大、密度增加对区域创新发展具有多方面的积极影响。文从分享、匹配和学习等视角进行了分析,并提出相关的政策建议。

关键词：城市规模密度区域创新