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先发海洋强国发展经验及对21世纪海上丝绸之路建设的启示 被引量:1
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作者 李睿 《产业创新研究》 2019年第1期11-13,21,共4页
"一带一路"倡议是我国站在人类命运共同体的高度,为全球经济绿色、共享、创新发展提出的一剂药方。本文聚焦我国过去五年发展取得的成就,关注先发海洋强国与当代海洋强国发展经历与取得经验,为我国更好地促进21世纪海上丝绸... "一带一路"倡议是我国站在人类命运共同体的高度,为全球经济绿色、共享、创新发展提出的一剂药方。本文聚焦我国过去五年发展取得的成就,关注先发海洋强国与当代海洋强国发展经历与取得经验,为我国更好地促进21世纪海上丝绸之路倡议落地提出5点启示:一是关注管理涉海管理体制的优化重组,将海洋战略谋划的权责上升至国家层级;二是加强对海洋战略的认识与研究,尤其是理论思想研究;三是加强科学技术与装备能力建设,重视海洋教育与国家软实力构建;四是深化国际合作,提升全球运输投送与战略支点的后勤保障能力。 展开更多
关键词 21世纪海上丝绸之路 海洋 重要启示
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Damage and fracture behavior and spatio-temporal evolution of acoustic emission of sandstone before and after laser radiation
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作者 GAO Ming-zhong LIU Jun-jun +6 位作者 LIChun-xiang YANG Ben-gao LI Fei ZHOU Xue-min YANG Lei YANG Zun-dong XIE Jing 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3264-3280,共17页
Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to su... Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to such radiation.The uniaxial compressive strength of sandstone notably decreases by 22.1%–54.7%following exposure to a 750 W laser for 30 s,indicating a substantial weakening effect.Furthermore,the elastic modulus and Poisson ratio of sandstone exhibit an average decrease of 33.7%and 25.9%,respectively.Simultaneously,laser radiation reduces the brittleness of sandstone,increases the dissipated energy proportion,and shifts the failure mode from tensile to tension-shear composite failure.Following laser radiation,both the number and energy of acoustic emission events in the sandstone register a substantial increase,with a more dispersed distribution of these events.In summary,laser radiation induces notable damage to the mechanical properties of sandstone,leading to a substantial decrease in elastic energy storage capacity.Laser rock breaking technology is expected to be applied in hard rock breaking engineering to significantly reduce the difficulty of rock breaking and improve rock breaking efficiency. 展开更多
关键词 laser rock breaking efficient drilling acoustic emission mechanical damage strength reduction
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Application of the Sub-Model Method in the Engine Strength Analysis 被引量:9
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作者 邹文胜 左正兴 +1 位作者 冯慧华 廖日东 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期260-265,共6页
On the basis of introducing the fundamental theory and the basic analysis steps of the sub model method, the strength of the new engine complex assembly structure was analyzed according to the properties of the engin... On the basis of introducing the fundamental theory and the basic analysis steps of the sub model method, the strength of the new engine complex assembly structure was analyzed according to the properties of the engine structures, some of the key parts of the engine were analyzed with refined mesh by sub model method and the error of the FEM solution was estimated by the extrapolation method. The example showed that the sub model can not only analyze the comlex structures without the restriction of the software and hardware of the computers, but get the more precise analysis result also. This method is more suitable for the strength analysis of the complex assembly structure. 展开更多
关键词 sub model method ENGINE strength analysis FEM
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An elasto-plastic constitutive model for soft rock considering mobilization of strength 被引量:6
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作者 李杭州 熊光东 赵桂平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第3期822-834,共13页
A new elasto-plastic constitutive model is presented in the framework of plasticity theory. The strength characteristics of a diatomaceous soft rock is investigated. The friction angle and cohesion of soft rock are mo... A new elasto-plastic constitutive model is presented in the framework of plasticity theory. The strength characteristics of a diatomaceous soft rock is investigated. The friction angle and cohesion of soft rock are mobilized as a function of plastic strain. A hyperbolic hardening function for the mobilized friction and a mixed parabolic and exponential equation for the mobilized cohesion are proposed. In view of the unified strength theory and the mobilizations of strength components, a yield function is given. A plastic potential function is determined by using the non-associated plastic flow rule. An elasto-plastic constitutive model is developed and verified. The results indicate that the proposed model can predict the behavior of soft rock accurately. The advantages of the proposed constitutive model are analyzed. The evidences support that the proposed constitutive model is a mixed hardening/softening model. A hump hardening/softening function for mobilized friction is extended to a more generalized condition. 展开更多
关键词 constitutive model mobilized strength component unified strength theory soft rock
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地震安全性评价中若干地震地质问题探讨 被引量:21
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作者 周本刚 沈得秀 《震灾防御技术》 2006年第2期113-120,共8页
本文在对活动断层的工程涵义进行了简要分析后,讨论了断层物质测年的工程应用进展及其断层活动时代鉴定问题,并就如何加强中强地震发震构造判别、应用地震地质资料评估大地震年平均发生率、以及活动断层地表断错位移的概率评价等问题作... 本文在对活动断层的工程涵义进行了简要分析后,讨论了断层物质测年的工程应用进展及其断层活动时代鉴定问题,并就如何加强中强地震发震构造判别、应用地震地质资料评估大地震年平均发生率、以及活动断层地表断错位移的概率评价等问题作了初步探讨。 展开更多
关键词 地震安全性评价 断层活动性鉴定 地震震构造 大地震年平均生率
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Effects of Dilute Acid-intensified Hydrolysis on Fermentative Biohydrogen Production Capacity of Maize Stalk 被引量:2
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作者 孙学习 李俊峰 +3 位作者 李涛 曾召刚 任保增 樊耀亭 《Agricultural Science & Technology》 CAS 2010年第8期1-3,共3页
[Objective] This study was to explore the effects of dilute acid hydrolysis on fermentative biohydrogen production capacity of maize stalk. [Method] Using maize stalks subjected to mechanical disintegration,steam expl... [Objective] This study was to explore the effects of dilute acid hydrolysis on fermentative biohydrogen production capacity of maize stalk. [Method] Using maize stalks subjected to mechanical disintegration,steam explosion and dilute acid hydrolysis as experimental materials,we measured and analyzed the effects of different treatments and particle size of maize stalk were analyzed. [Result] The optimal fermentative biohydrogen production was found under following parameters:pretreatment of 0.8% dilute H2SO4 following steam explosion,particle size of maize stalk of 0.425-0.850 mm,liquid-solid ratio [0.8% H2SO4 (M):stalk (W)] of 10:1. [Conclusion] Post steam explosion,dilute 0.8% dilute H2SO4 intensified hydrolysis on maize stalk could produce fermentative biohydrogen production capacity. 展开更多
关键词 Maize stalk Dilute acid-intensified hydrolysis Fermentative biohydrogen production
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Cultural and luminescent Conditions of a Marine luminous Bacterium
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作者 方宏达 董燕红 +2 位作者 袁茵 李秀芹 易斌 《Marine Science Bulletin》 CAS 2008年第1期46-53,共8页
Study of marine noctilucence in marine is important to fishery, environmental monitoring and military affairs. A luminous bacterial strain D2 was isolated from the marine sediment samples collected near Donghai Island... Study of marine noctilucence in marine is important to fishery, environmental monitoring and military affairs. A luminous bacterial strain D2 was isolated from the marine sediment samples collected near Donghai Island in Zhanjiang, China. The primary cultural and luminescent conditions of luminous bacterium D2 which was identified as Vibrio sp. were determined in liquid culture. The results showed that pH 7.0, 35 ℃, with 2.0 % NaCI, were the best growth conditions, and pH5 - 6, 20℃, OD600 0.08, with 3.0 % NaCI, were the optimal luminescent conditions. 展开更多
关键词 Luminous bacterium growth conditions luminescent conditions quorum sensing system
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Porosity Determination Equation for Porous Silicon
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作者 廉德亮 谢国伟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第7期817-820,共4页
Through the studying of the carriers moving of the porous and the definition of S BET ,the equation of the relationship among the porosity,the current density and the etching speed can be deduced.Here,it is sh... Through the studying of the carriers moving of the porous and the definition of S BET ,the equation of the relationship among the porosity,the current density and the etching speed can be deduced.Here,it is shown that for porous silicon made from p type silicon,there is a universal relationship,it is possible to determine the change in porosity with respect to etching under a set etching current density.This relationship is checked against experimental data from several reports on these etching parameters,and they confirm the validity. 展开更多
关键词 POROSITY porous silicon luminescence intensity
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Effects of Light Intensity on Growth, Development and Formation on Fagopyrum cymosum 被引量:1
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作者 华劲松 戴红燕 《Agricultural Science & Technology》 CAS 2014年第3期363-366,共4页
Effects of light intensity on growth, development and formation on Fagopy- rum cymosum were explored with natural light intensities at 100%(A), 85.2%(B), 75.8%(C) and 59.7%(D). The results showed that the decl... Effects of light intensity on growth, development and formation on Fagopy- rum cymosum were explored with natural light intensities at 100%(A), 85.2%(B), 75.8%(C) and 59.7%(D). The results showed that the decline of light intensity re- duced nutrient growth period, so that plant growth stage entered in advance and extended, which indicated that the decline of light intensity would lower leaf number and area, the number of twigs from the stem, as well as photosynthate. Further- more, the reduction degree increased upon light intensity decrease degree, and the proper shading improved stem height and leaf area enhanced before growth term. 展开更多
关键词 Fagopyrum cymosum Light intensity Growth and development Morpho- logical characters
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Neutral Dissociation of Superexcited Nitric Oxide Induced by Intense Laser Fields
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作者 刘凯 宋迪 +2 位作者 Ali Azarm See-Leang Chin 孔繁敖 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期252-254,I0001,共4页
Superexcited states of NO molecule and their neutral dissociation processes have been studied both experimentally and theoretically. Neutral excited N^* and O^* atoms are detected by fluorescence spectroscopy for th... Superexcited states of NO molecule and their neutral dissociation processes have been studied both experimentally and theoretically. Neutral excited N^* and O^* atoms are detected by fluorescence spectroscopy for the NO molecule upon interaction with 800 nm intense laser radiation of duration 60 fs and intensity 0.2 PW/cm^2. Intense laser pulse causes neutral dissociation of superexcited NO molecule by way of multiphoton excitation, which is equivalent to single photon excitation in the extreme-ultraviolet region by synchrotron radiation. Potential energy curves (PECs) are also built using the calculated superexcited state of NO^+. In light of the PECs, direct dissociation and pre-dissociation mechanisms are proposed respectively for the neutral dissociation leading to excited fragments N^* and O^*. 展开更多
关键词 Superexcited state Neutral dissociation Intense laser
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Resonance-Enhanced Photon Excitation Spectroscopy of the Even-Parity 3p^5(2P1/2)nl′ [K′]J (l′=1, 3) Autoionizing Rydberg States of Ar
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作者 李春燕 何志巍 +3 位作者 王婷婷 甄军锋 陈旸 张劲松 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第3期259-264,I0003,共7页
Metastable 40Ar* atoms are produced in the two metastable states 3p54s [3/2]2 and 3p5 4s′ [1/2]0 in a pulsed DC discharge in a beam, and are subsequently excited to the even-parity autoionizing resonance series 3pSn... Metastable 40Ar* atoms are produced in the two metastable states 3p54s [3/2]2 and 3p5 4s′ [1/2]0 in a pulsed DC discharge in a beam, and are subsequently excited to the even-parity autoionizing resonance series 3pSnp′[3/2]1,2, 3p5 np′ [1/2]1, and 3p5nf′[5/2]3 using single photon excitation with a pulsed dye laser. The excitation spectra of the even-parity autoion- izing resonance series from the metastable 40Ar* are obtained by recording the autoionized Ar+ ions with time-of-flight ion detection in the photon energy range of 32500-35600 cm-1 with an experimental bandwidth of 〈0.1 cm-1. A wealth of autoionizing resonances are newly observed, from which more precise and systematic spectroscopic data of the level energies and quantum defects are derived. 展开更多
关键词 AR Pulsed DC discharge Resonance-enhanced photon excitation spectroscopy Autoionizing Rydberg resonance
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《中国研究型医院》杂志征稿启事
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《中国研究型医院》 2017年第5期5-5,共1页
《中国研究型医院》(JOURNAL OF RESEARCH HOPITALS)杂志是中华人民共和国民政部主管,由中国研究型医院学会和中国科学技术出版社主办,中国研究型医院学会名誉会长、原解放军总后勤部副部长秦银河担任名誉主编,中国研究型医院学会会... 《中国研究型医院》(JOURNAL OF RESEARCH HOPITALS)杂志是中华人民共和国民政部主管,由中国研究型医院学会和中国科学技术出版社主办,中国研究型医院学会名誉会长、原解放军总后勤部副部长秦银河担任名誉主编,中国研究型医院学会会长王发强担任总编辑。向国内外公开发行的医院管理及医学创新综合类中英文"双语"学术期刊。中国标准连续出版物刊号(CSSN): 展开更多
关键词 研究型医院 出版物刊号 名誉主编 医院管理 医学创新 银河 发强 学会名誉会长 双语 学术期刊
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全国老年体育健身主题示范活动在池州举行
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《运动》 2017年第16期157-157,共1页
全民健身日·全国老年体育健身主题示范活动暨第三届全国老年人体育健身大会健身气功交流活动于2017年8月7日在安徽省池州市开幕。国家体育总局副局长赵勇、安徽省人民政府副省长谢广祥、中国老年人体育协会主席张发强、全国老龄办... 全民健身日·全国老年体育健身主题示范活动暨第三届全国老年人体育健身大会健身气功交流活动于2017年8月7日在安徽省池州市开幕。国家体育总局副局长赵勇、安徽省人民政府副省长谢广祥、中国老年人体育协会主席张发强、全国老龄办巡视员曹健等出席开幕式。 展开更多
关键词 老年体育 老年人体育协会 健身气功 全国老龄办 赵勇 国家战略 发强 人民政府 副局长 示范活动
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全国森林工程标准化技术委员会2017年年会暨标准审定会于11月3日在云南省昆明市召开
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《林业机械与木工设备》 2017年第12期35-35,共1页
全国森林工程标准化技术委员会2017年年会暨标准审定会于2017年11月3日在云南省昆明市召开,出席此次会议的有全国森林工程标准化技术委员会的委员和专家共23人。年会由国家林业局哈尔滨林业机械研究所徐克生副所长主持,国家林业局科技... 全国森林工程标准化技术委员会2017年年会暨标准审定会于2017年11月3日在云南省昆明市召开,出席此次会议的有全国森林工程标准化技术委员会的委员和专家共23人。年会由国家林业局哈尔滨林业机械研究所徐克生副所长主持,国家林业局科技司黄发强副司长和标准处程强副处长到会指导。 展开更多
关键词 森林工程 标准审定会 国家林业局 昆明市 工作总结报告 林业机械 徐克 发强 标准体系表 行业标准
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Fabrication and testing of phase change heat sink for high power LED 被引量:1
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作者 向建化 张春良 +2 位作者 江帆 刘晓初 汤勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2066-2071,共6页
A novel phase change heat sink was fabricated for packaging cooling of high power light emitting diode (LED). 3D structures as enhanced boiling structure in the evaporation surface were composed of a spiral micro-gr... A novel phase change heat sink was fabricated for packaging cooling of high power light emitting diode (LED). 3D structures as enhanced boiling structure in the evaporation surface were composed of a spiral micro-groove along circumferential direction and radial micro-grooves which were processed by ploughing-extrusion (P-E) and stamping, respectively. Meanwhile, the cycle power of refrigerant was supplied by wick of sintered copper powder on internal surface of phase change heat sink. Operational characteristics were tested under different heat loads and refrigerants. The experimental results show that phase change heat sink is provided with a good heat transfer capability and the temperature of phase change heat sink reaches 86.8 ℃ under input power of 10 W LED at ambient temperature of 20 ℃. 展开更多
关键词 high power light emitting diode phase change heat sink enhanced boiling WICK heat transfer performance
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CONDITION-BASED MAINTENANCE DECISION MAKING METHODS FOR CIVIL AEROENGINE 被引量:6
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作者 戎翔 左洪福 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期201-207,共7页
To provide some feasible condition-based maintenance (CBM) decision making methods for civil aeroengine, firstly, the theory of aeroengine CBM decision making is described. The proportional intensity(PI) model is ... To provide some feasible condition-based maintenance (CBM) decision making methods for civil aeroengine, firstly, the theory of aeroengine CBM decision making is described. The proportional intensity(PI) model is established based on the reliability and condition monitoring data. According to the model, the decision making methods are proposed for the optimal preventive maintenance(PM) interval and removal. Then, the time on wing (TOW) is predicted by collecting actual data based on the engine age and operating conditions. Finally, an example of a fleet for CF6-80C2 engines is illustrated. It shows that sufficient engine operation data are the key of accurate decision making. Results indicate that the CBM decision making methods are helpful for engineers in airlines to control engine maintenance actions and TOW, thus decreasing risks and maintenance costs. 展开更多
关键词 civil aviation aircraft engines maintenance condition-based maintenance proportional intensity model
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Electron Injection Enhancement by Diamond-Like Carbon Film in Polymer Electroluminescence Devices
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作者 李宏建 闫玲玲 +4 位作者 黄伯云 易丹青 胡锦 何英旋 彭景翠 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第1期30-34,共5页
A diamond-like carbon (DLC) film is deposited as an electron injection layer between the polymer light-emitting layer(MEH-PPV) and aluminum (Al) cathode electrode in polymer electroluminescence devices (PLEDs)... A diamond-like carbon (DLC) film is deposited as an electron injection layer between the polymer light-emitting layer(MEH-PPV) and aluminum (Al) cathode electrode in polymer electroluminescence devices (PLEDs) using a radio frequency plasma deposition system. The source material of the DLC is n-butylamine. The devices consist of indium tin oxide (ITO)/MEH-PPV/DLC/Al. Electron injection properties are investigated through I-V characteristics,and the mechanism of electron injection enhancement due to a thin DLC layer has been studied. It is found that: (1) a DLC layer thinner than 1.0nm leads to a higher turn-on voltage and decreased electroluminescent (EL) efficiency; (2) a 5.0nm DLC layer significantly enhances the electron injection and results in the lowest turn-on voltage and the highest EL efficiency; (3) DLC layer that exceeds 5.0nm results in poor device performance;and(4) EL emission can hardly be detected when the layer exceeds 10.0nm. The properties of ITO/MEH-PPV/DLC/Al and ITO/MEH-PPV/LiF/Al are investigated comparatively. 展开更多
关键词 diamond-like carbon polymer electroluminescence device electron injection enhancement
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Research on changes of coastal land use intensity in bay area during past 30 years——A case study of Xiangshan Bay 被引量:4
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作者 FENG Bai-xiang LI Jia-lin +1 位作者 HE Gai-li HUANG Ri-peng 《Marine Science Bulletin》 CAS 2018年第2期28-43,共16页
Taking the coastal zone of Xiangshan Bay as a study area,based on the information of four TM images of1985,1995,2005,and2015,this study divided the land use types into8categories.Then,through calculating4kinds of inde... Taking the coastal zone of Xiangshan Bay as a study area,based on the information of four TM images of1985,1995,2005,and2015,this study divided the land use types into8categories.Then,through calculating4kinds of index models:land-use dynamic index,conversion matrix,land use structure information entropy,and comprehensive index of land development and utilization intensity,the speed,structure,degree,and the spatial-temporal changes in the land development and utilization of Xiangshan Bay coastal zone from1985to2015are researched and analyzed.Results showed that:from1985to2015,the expansion speed of aquaculture land and salt pan of Xiangshan Bay coastal zone was the fastest,the highest dynamic degree could up to11.97%,construction land expansion rate of the second,with significant increase in the area.Intertidal zone reduced by a maximum speed,and the area of farmland decreased obviously.In that30years,the main land type change direction of Xiangshan Bay coastal zone was the farmland turn into construction land,followed by forest turn into farmland.Information entropy increased by period,the land use structure homogeneity constantly strengthened and regional development became gradually mature.The change rate of land use intensity in each period was greater than zero,and the intensity of land development and utilization in Xiangshan Bay coastal zone was enhanced continuously. 展开更多
关键词 land use development intensity spatial-temporal changes coastal zone of Xiangshan Bay
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NECESSARY CONDITION OF IDENTIFICATION FOR A DISTRIBUTED PARAMETER SYSTEM
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作者 金振东 梁洪俊 +1 位作者 喻文焕 李光泉 《Transactions of Tianjin University》 EI CAS 2000年第2期130-134,共页
This paper considers the necessary condition of the parameter identification problem dudt=(A+B(q))u u(0)=x x∈X with the cost functional J(q)≡12∫ T 0‖Cu(t;q)-y(t)‖ 2 H d t It is proved that the optimal... This paper considers the necessary condition of the parameter identification problem dudt=(A+B(q))u u(0)=x x∈X with the cost functional J(q)≡12∫ T 0‖Cu(t;q)-y(t)‖ 2 H d t It is proved that the optimal estimate q 0 is determined by the optimal system which consists of the sate equation,the adjoint equation and the optimal condition. 展开更多
关键词 C0-semigroup evolution equation strongly Frechet differential parameter identification optimal system
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Ultimate Strength Assessment of a Tanker Hull Based on Experimentally Developed Master Curves 被引量:1
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作者 Mingcai Xu Y. Garbatov C. Guedes Soares 《Journal of Marine Science and Application》 2013年第2期127-139,共13页
A geometrically similar scaling was made from small-scale specimen to full-scale stiffened panels and then their collapse behaviour is investigated. It is considered that the stiffened panel compressive ultimate stren... A geometrically similar scaling was made from small-scale specimen to full-scale stiffened panels and then their collapse behaviour is investigated. It is considered that the stiffened panel compressive ultimate strength test was designed according to geometrical scaling laws so that the output of the test could be used as representative of the stiffened panels of the compressive zone of a tanker hull subjected to vertical bending moment. The ultimate strength of a tanker hull is analysed by a FE analysis using the experimentally developed master stress-strain curves which are obtained by the beam tension test and the compressive test of the stiffened panel, and are then compared with the result achieved by the progressive collapse method. 展开更多
关键词 ship hull tanker hull stiffened panel ultimate strength scaling laws similitude analysis
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