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Platinum Nanoparticle-based Collision Electrochemistry for Rapid Detection of Breast Cancer MCF-7 Cells
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作者 Fu-Xing Qin Ming-Ke Li +4 位作者 Hui-Long Zhou Wei Wen Xiu-Hua Zhang Sheng-Fu Wang Zhen Wu 《电化学(中英文)》 CAS 北大核心 2024年第10期19-27,共9页
Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content... Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content of CTCs in peripheral blood is minimal,so the detection of CTCs in real samples is extremely challenging.Therefore,efficient enrichment and early detection of CTCs are essential to achieve timely diagnosis of diseases.In this work,we constructed an innovative and sensitive single-nanoparticle collision electrochemistry(SNCE)biosensor for the detection of MCF-7 cells(human breast cancer cells)by immunomagnetic separation technique and liposome signal amplification strategy.Liposomes embedded with platinum nanoparticles(Pt NPs)were used as signal probes,and homemade gold ultramicroelectrodes(Au UME)were used as the working electrodes.The effective collision between Pt NPs and UME would produce distinguishable step-type current.MCF-7 cells were accurately quantified according to the relationship between cell concentration and collision frequency(the number of step-type currents generated per unit time),realizing highly sensitive and specific detection of MCF-7 cells.The SNCE biosensor has a linear range of 10 cells·mL^(-1)to 10^(5) cells·mL^(-1)with a detection limit as low as 5 cells·mL^(-1).In addition,the successful detection of MCF-7 cells in complex samples showed that the SNCE biosensors have great potential for patient sample detection. 展开更多
关键词 Circulating tumor cells Single-nanoparticle collision electrochemistry Immunomagnetic separation LIPOSOME Platinum nanoparticles
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A self-organization formation configuration based assignment probability and collision detection
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作者 SONG Wei WANG Tong +1 位作者 YANG Guangxin ZHANG Peng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期222-232,共11页
The formation control of multiple unmanned aerial vehicles(multi-UAVs)has always been a research hotspot.Based on the straight line trajectory,a multi-UAVs target point assignment algorithm based on the assignment pro... The formation control of multiple unmanned aerial vehicles(multi-UAVs)has always been a research hotspot.Based on the straight line trajectory,a multi-UAVs target point assignment algorithm based on the assignment probability is proposed to achieve the shortest overall formation path of multi-UAVs with low complexity and reduce the energy consumption.In order to avoid the collision between UAVs in the formation process,the concept of safety ball is introduced,and the collision detection based on continuous motion of two time slots and the lane occupation detection after motion is proposed to avoid collision between UAVs.Based on the idea of game theory,a method of UAV motion form setting based on the maximization of interests is proposed,including the maximization of self-interest and the maximization of formation interest is proposed,so that multi-UAVs can complete the formation task quickly and reasonably with the linear trajectory assigned in advance.Finally,through simulation verification,the multi-UAVs target assignment algorithm based on the assignment probability proposed in this paper can effectively reduce the total path length,and the UAV motion selection method based on the maximization interests can effectively complete the task formation. 展开更多
关键词 straight line trajectory assignment probability collision detection lane occupation detection maximization of interests
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F-Law collision and system state recognition 被引量:4
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作者 Shi Kaiquan Xu Xiaojing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期259-264,共6页
Using function one direction S-rough sets (function one direction singular rough sets), f-law and F- law and the concept of law distance and the concept of system law collided by F-law are given. Using these concept... Using function one direction S-rough sets (function one direction singular rough sets), f-law and F- law and the concept of law distance and the concept of system law collided by F-law are given. Using these concepts, state characteristic presented by system law collided by F-law and recognition of these states characteristic and recognition criterion and applications are given. Function one direction S-rough sets is one of basic forms of function S-rough sets (function singular rough sets). Function one direction S-rough sets is importance theory and is a method in studying system law collision. 展开更多
关键词 Function one direction S-rough sets F -law collision Characteristic recognition Recognition criterion Applications.
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一种估测运动目标Time-to-Collision的方法 被引量:2
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作者 李俊 张桂林 《数据采集与处理》 CSCD 1998年第3期236-240,共5页
提出了一种直接从图象序列中估测运动目标到被攻击物体的撞击时间的方法,建立了目标运动的象面模型,并设计了一种利用多子区相关跟踪器和最小二乘估计方法估测撞击时间的方案。计算机仿真实验结果证明了该方案的可行性。
关键词 计算机视觉 景象匹配 撞击时间 导弹 惯性制导
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THE CENTRAL PAMIR—AN ALPINE COLLISION ZONE 被引量:1
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作者 M.S.Dufour (Saint\|Petersburg University. Saint\|Petersburg, Russia St.Petersburg State University,Universitetskaya emb. 7/9. 199034 St.Petersburg, Russia,E\|mail:lena@hq.pu.ru) 《地学前缘》 EI CAS CSCD 2000年第S1期256-256,共1页
The Alpine zone of Central Pamir is elongated in sublatitudinal direction between the Hercynians of Northern Pamir and the Cimmerians of Southern Pamir south of the Vanch\|Akbaital thrust. Its western continuation is ... The Alpine zone of Central Pamir is elongated in sublatitudinal direction between the Hercynians of Northern Pamir and the Cimmerians of Southern Pamir south of the Vanch\|Akbaital thrust. Its western continuation is overthrusted by the Herat fault and its eastern continuation is cut by the Karakoram strike\|slip fault.. The Central Pamir is a mainly S\|vergent (at the southern part N\|vergent) Alpine nappe stack then folding in antiform. It comprises deposits from Vendian to Neogene which have a thickness of 10km. Paleozoic and Mesozoic tectonic activity was poorly displaied in its limits. Rifting took place in Early and probably Upper Paleozoic. Pre\|Upper Cretaceous unconformity is known only in southern (autochthonous) part of the Zone as a result of closing of Bangong\|Nu Jiang ocean. In northern (allochthonous) part of the zone the sequence of Mesozoic and Paleogene rocks has no unconformities. Alpine endogenous processes were developed very intensively. They implied nappes and imbricate structures, linear folding, different igneous activity, zonal metamorphism. Slices of pyroxenites and gabbroids occured. Calc\|alkaline lavas and tuffs constitutes the major part of Paleocene to Miocene sequence (andesites\|ryolites\|in Paleogene, alkaline basalts in Oligocene—Miocene). Oligocene—Miocene zonal metamorphic belt of the intermediate type of high pressure including series of granitegneiss domes can be traced along the Central Pamir. Cores of domes include migmatites and remobilized bodies of the Early Paleozoic gneissic granites. The decompression took place at a later stage and rocks were overprinted by the andalusite\|sillimanite type metamorphism.. Syenite and leucogranite bodies, pegmatite and aplite veins were emplaced. 展开更多
关键词 CENTRAL PAMIR ALPINE collision METAMORPHIC belt INT racontinental SUBDUCTION
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Fracture mechanism of a cylindrical shell cut by circumferential detonation collision 被引量:4
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作者 He-yang Xu Wei-bing Li +4 位作者 Wen-bin Li Qing Zhang Ya-jun Wang Xiao-wen Hong Ying Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1650-1659,共10页
The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated.A self-designed detonation wave regulator was used to control the... The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated.A self-designed detonation wave regulator was used to control the detonation and cut the shell.It was found that the self-designed regulator controlled the fragment shape.The macrostructure and micro-characteristics of fragments revealed that shear fracture was a prior mechanism,the shell fractured not only at the position of detonation collision,but the crack also penetrated the shell at the first contact position of the Chapmen-Jouguet(C-J)wave.The effects of groove number and outer layer thickness on the fracture behavior were tested by simulations.When the thickness of the outer layer was 5e18 mm,it has little effect on fragmentation of the shell,and shells all fractured at similar positions.The increase of the groove number reduced the fracture possibility of the first contact position of the C-J wave.When the groove number reached 7 with a 10 mm outer layer(1/4 model),the fracture only occurred at the position of detonation collision and the fragment width rebounded. 展开更多
关键词 Detonation wave Circumferential detonation collision Fracture mechanism Fragmentation control
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Crashworthiness design and experimental validation of a novel collision post structure for subway cab cars 被引量:4
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作者 XING Jie XU Ping +3 位作者 ZHAO Hui YAO Shu-guang WANG Qian-xuan LI Ben-huai 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第9期2763-2775,共13页
This paper proposes a novel collision post structure designed to improve the crashworthiness of subway cab cars.The structure provides two innovative features:1)a simpler connection between the post and the car roof,w... This paper proposes a novel collision post structure designed to improve the crashworthiness of subway cab cars.The structure provides two innovative features:1)a simpler connection between the post and the car roof,which gives a more reasonable load transfer path to reduce the stress concentration at the joint;and 2)a stiffness induction design that provides an ideal deformation model to protect the safe space of the cab cars.The novel collision post structure was evaluated with finite element analysis,and a prototype cab car was mechanically tested.The results demonstrate that the deformation response was stable and agreed well with the expected ideal mode.The maximum load was 874.17 kN and the responses remained well above the elastic design load of 334 kN as required by the design specification.In addition,there was no significant tearing failure during the whole test process.Therefore,the novel collision post structure proposed has met the requirements specified in new standard to improve the crashworthiness of subway cab cars.Finally,the energy absorption efficiency and light weight design highlights were also summarized and discussed. 展开更多
关键词 collision post structure subway cab cars CRASHWORTHINESS quasi-static test
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■-law collision and system state recognition 被引量:1
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作者 Shi Kaiquan Chen Hui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期509-514,共6页
Using dual function one direction S-rough sets, this article gives the f-law, the F-law, law distance and the concept of system law collided by the F-law. The characteristics presented by the system law collided by th... Using dual function one direction S-rough sets, this article gives the f-law, the F-law, law distance and the concept of system law collided by the F-law. The characteristics presented by the system law collided by the F-law, the recognition of these characteristics and recognition criterion are also proposed. The dual function one direction S-rough sets is one of the basic forms of function S-rough sets. Its basic theory and application in the study of system law collision are reviewed. 展开更多
关键词 dual function one direction S-rough sets F-law collision characteristic recognition recognition criterion applications.
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Composition ship collision risk based on fuzzy theory 被引量:4
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作者 CHEN Shu Rashid Ahmad +1 位作者 Byung-Gil Lee Do Hyeun Kim 《Journal of Central South University》 SCIE EI CAS 2014年第11期4296-4302,共7页
Despite of modern navigation devices, there are problems in navigation of vessels in waterways due to the geographical structures, disturbances in water, dynamic nature, and heavily environmental influenced sea traffi... Despite of modern navigation devices, there are problems in navigation of vessels in waterways due to the geographical structures, disturbances in water, dynamic nature, and heavily environmental influenced sea traffic. Even though all vessels are equipped with modern navigation devices, the accidents are reported caused by various reasons and mainly by human factor according to investigation. We propose an effective and efficient composition collision risk calculation method for finding the collision probability and avoiding the collision between ships in possible collision situations. The proposed composition collision risk calculation method at ship's position using combination of fuzzy and fuzzy comprehensive evaluation methods. The algorithm is straightforward to implement and is shown to be effective in automatic ship handling for ships involved in complex navigation situations. Experiments are carried out with indigenous data and the results show the effectiveness of the proposed approach. 展开更多
关键词 automatic ship navigation collision risk fuzzy theory
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Simulation of Head-Disk Collisions in Magnetic Disk Drives
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作者 Zhu Yaolong, Zhou Xueren, and Yang YinpuBeijing Institute of Data Processing Technology P.O.Box: 3927, Beijing 100854, P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第4期26-32,共7页
Head disk collision models of 'coefficient-of-restitution' are widely used in the head disk interface simulation. A new head disk collision model called 'critical velocity model' has been developed. Nu... Head disk collision models of 'coefficient-of-restitution' are widely used in the head disk interface simulation. A new head disk collision model called 'critical velocity model' has been developed. Numerical simulation of dynamics of a typical Winchester-type slider is presented under the influence of head disk collisions due to disk surface defects such as localize asperities. Two kinds of head disk collision models have been compared and analysed. The results show that the critical velocity is a very important parameter which affects the dynamics of the slider. 展开更多
关键词 Magnetic disks TRIBOLOGY collision Hydrodynamics.
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Search Algorithm for Determining the Range of the Possible Collision of Conver Polygons
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作者 Li Qinghua(Department of Computer Science and EngineeringHuazhong University of Science Technology, Wuhan, 430074, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第3期31-42,共12页
Let P=(po, p1,..., pn-1 ) and Q=(qo,q1..., qm-1) be two arbitrary convex polygonsin plane. In this paper, the author studies the problems of how to quickly determine their possiblecollision range and movable range. In... Let P=(po, p1,..., pn-1 ) and Q=(qo,q1..., qm-1) be two arbitrary convex polygonsin plane. In this paper, the author studies the problems of how to quickly determine their possiblecollision range and movable range. In the paper, a new sufficient and necessary condition for decidingpossible collision is proposed,and the basic characters of the oblique supporting lines are investigated,and on these grounds the problem to determine the possible collision range is transformed into thatof searching the supporting points on the sets of convex polygon vertexs. Using the strategy ofsearching simultaneously the sets of vertexes of P and Q, the author constructs the fast algorithmfor finding the supporting points, the time-complexity of which is O(log2(m + n)). Based on theseresults, the algorithms to quickly determine the range are given, which possess the time-complexityof O(log2(m+n)). 展开更多
关键词 Possible collision Ranges of possible and impossible collision Oblique supporting line Supporting points.
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Simulation on Collision of Bird with Windshield by Using MCA
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作者 罗荣梅 黄德武 王猛 《Defence Technology(防务技术)》 CAS 2012年第2期86-91,共6页
The collision process of a flying bird and the aircraft windshield was simulated by using movable cellular automata ( MCA) method to improve the structure design of aircrafts. The simulation results show that the whol... The collision process of a flying bird and the aircraft windshield was simulated by using movable cellular automata ( MCA) method to improve the structure design of aircrafts. The simulation results show that the whole strike process is performed in 4. 8 ms,the critical strike velocity for an aeronautic glass windshield is 360 km/h,the windshield vibrates and deforms in the collision,and after absorbing the kinetic energy,its temperature increases. The simulation results coincide with the experiment data better. It is clear that MCA method has more advantages than the usual methods of continuum mechanics. 展开更多
关键词 experimental technology of aerocraft MCA method flying bird strike collision WINDSHIELD movable cellular automation critical velocity
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Geochemistry and Sr,Nd Istopes of Granitoids from the Lac Ifni Area(Sirwa Massif-Anti-Atlas Morocco):A Geodynamic Setting for the Post-collisional Ediacaran Magmatic Chain of the Anti-Atlas
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作者 Lagage 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期200-200,共1页
The plutonic rocks of the westernmost part of the Sirwa massif belong to the Ediacaran post-collisional magmatic chain of the Anti-Atlas.The geochemistry of major and trace elements attests that the fractional crystal... The plutonic rocks of the westernmost part of the Sirwa massif belong to the Ediacaran post-collisional magmatic chain of the Anti-Atlas.The geochemistry of major and trace elements attests that the fractional crystallization cannot account for the variations between the granitoids and the associated MME.They represent two contemporaneous but independent magmatic tendencies.However,Sr and Nd configur data argue for a similar and juvenile material 展开更多
关键词 EDIACARAN ANTI-ATLAS GRANITOIDS POST-collision juvenile source breakoff delamination
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非正交面齿轮传动系统的擦边碰撞特性分析 被引量:1
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作者 高建设 吴家宝 +2 位作者 吴鲁纪 杨林杰 饶晓波 《振动与冲击》 北大核心 2025年第5期1-11,17,共12页
为深入研究非正交面齿轮传动系统中的擦边碰撞现象,以齿面碰撞面和齿背碰撞面为分界面,将相空间划分为三个部分,构建了考虑多种强非线性因素的非正交面齿轮传动系统动力学模型。在两分界面建立位置Poincaré映射,并对擦边分岔条件... 为深入研究非正交面齿轮传动系统中的擦边碰撞现象,以齿面碰撞面和齿背碰撞面为分界面,将相空间划分为三个部分,构建了考虑多种强非线性因素的非正交面齿轮传动系统动力学模型。在两分界面建立位置Poincaré映射,并对擦边分岔条件进行计算,随后结合啮合力周期变化图和相图找到擦边分岔点,并对分岔点附近的Floquet乘子进行求解,通过分析擦边分岔对系统动力学的影响来揭示擦边碰撞特性,最后利用Adams软件进行仿真验证。研究表明:擦边碰撞会导致面齿轮传动系统冲击状态发生改变,通常不会对面齿轮传动系统的运动状态造成影响;当擦边分岔与倍周期分岔同时发生时,面齿轮传动系统会出现余维二擦边分岔,此时,擦边碰撞会导致系统运动状态与冲击状态均发生改变。此研究结果为工程中提高面齿轮传动系统的可靠性和寿命提供理论依据。 展开更多
关键词 擦边碰撞 擦边分岔 非光滑系统 面齿轮 冲击
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船冰多次碰撞下极地航行船舶舷侧结构动态响应研究 被引量:1
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作者 姜河蓉 姜金辉 +1 位作者 杨泽文 袁昱超 《舰船科学技术》 北大核心 2025年第1期8-13,共6页
近年来全球变暖的加剧使得北极航道的开放更具可行性,为分析极地船舶航行过程中的冰载荷及船体结构响应特性,本文针对船体舷侧结构与浮冰场多次碰撞的场景开展数值仿真研究。参考现阶段浮冰观测统计经验,建立船体舷侧结构-浮冰场相互作... 近年来全球变暖的加剧使得北极航道的开放更具可行性,为分析极地船舶航行过程中的冰载荷及船体结构响应特性,本文针对船体舷侧结构与浮冰场多次碰撞的场景开展数值仿真研究。参考现阶段浮冰观测统计经验,建立船体舷侧结构-浮冰场相互作用有限元数值模型,在不同碰撞角度与不同浮冰密集度下开展仿真计算,分析船冰连续多次碰撞过程中碰撞力、能量及响应数据,研究碰撞角度和浮冰场密集度对浮冰载荷及船体舷侧结构响应特性的影响规律。结果表明,船冰多次相互作用下的结构响应规律与船冰单次作用存在一定差异,碰撞角度与浮冰场密集度参数对船冰碰撞力与船体舷侧结构响应特征影响呈现出一定的规律。本文研究内容对极地航行船舶舷侧结构的安全性设计具有参考价值。 展开更多
关键词 船-冰多次碰撞 舷侧结构 结构响应 非线性有限元方法
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考虑冗余距离的融合空域下无人机防撞研究
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作者 王莉莉 闵幸兴 +1 位作者 孟令航 许皓星 《安全与环境学报》 北大核心 2025年第3期978-987,共10页
针对融合空域内,无人机需对存在潜在冲突风险的有人机进行探测和解脱的问题,提出在无人机上安装广播式自动相关监视接收端(Automatic Dependent Surveillance-Broadcast IN,ADS-B IN)系统来接收有人机机载广播式自动相关监视发射端(Auto... 针对融合空域内,无人机需对存在潜在冲突风险的有人机进行探测和解脱的问题,提出在无人机上安装广播式自动相关监视接收端(Automatic Dependent Surveillance-Broadcast IN,ADS-B IN)系统来接收有人机机载广播式自动相关监视发射端(Automatic Dependent Surveillance-Broadcast OUT,ADS-B OUT)系统发出的位置、航向等信息。从实际运行的安全角度出发,在以两架航空器半径之和构成的有人机球体保护区范围的基础上,引入ADS-B系统内数据接收处理及传输所产生的延迟距离。此外,考虑到当无人机位于有人机的尾流影响范围内时可能产生的不利影响,计算出前机诱导速度对后机产生的诱导滚转力矩,从而得到尾流影响下的安全距离,进一步调整有人机保护区的边界范围,建立两机之间的防撞模型。针对无人机在遇到潜在碰撞风险时的响应机制,根据最快解脱和最小机动原则,设置了二维平面下调整速度和航向的解脱方案,并在三维场景中,优化了传统的速度障碍法模型,进一步通过改变无人机的俯仰角来调整高度实现有效避让。为验证上述策略的有效性,最后设置仿真试验场景进行模拟试验,仿真结果满足最低间隔标准的要求,无人机防撞完成。 展开更多
关键词 安全工程 融合空域 无人机防撞 冲突解脱 冗余距离
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单塔斜拉桥在船舶撞击下动力响应及防撞设计
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作者 田力 张晗奇 《天津大学学报(自然科学与工程技术版)》 北大核心 2025年第4期343-356,共14页
首先,利用ANSYS/LS-DYNA有限元软件建立船-桥碰撞有限元模型,以附加质量模型考虑流体效应,利用落锤冲击试验验证了撞击作用下混凝土本构模型的有效性.其次,开展了不同撞击角度、不同船舶航速下船舶高速撞击斜拉桥桥塔数值模拟,分析了桥... 首先,利用ANSYS/LS-DYNA有限元软件建立船-桥碰撞有限元模型,以附加质量模型考虑流体效应,利用落锤冲击试验验证了撞击作用下混凝土本构模型的有效性.其次,开展了不同撞击角度、不同船舶航速下船舶高速撞击斜拉桥桥塔数值模拟,分析了桥塔损伤、碰撞力、桥塔位移、桥面位移、索力变化等方面的差异,并将碰撞力与国内外规范公式进行对比分析.再次,研究了30.0节(1节=0.5144 m/s)船速下桥塔瞬时倒塌过程及桥塔受损后持续荷载作用下倒塌机理.最后,为桥塔设计一种以FRP和橡胶为主要材料的防撞装置,模拟分析其在降低桥塔动力响应方面的防撞效果.结果表明:当船舶以高速撞击斜拉桥桥塔时,船桥碰撞整体动力响应随撞击角度和船舶航速增大而增大;采用一些国内外规范中的碰撞力公式偏于不安全;船桥碰撞后斜拉索索力迅速增大,靠近桥塔处索力变化率最大;船速为30.0节时,桥塔在碰撞后发生桥塔肢腿错位断裂的倒塌;船速为25.0节时,塔柱已有较大损伤破口,桥塔在遭受船舶碰撞后向碰撞侧倾斜,在重力及桥面荷载的持续作用下桥塔侧向位移逐渐增大而发生桥塔倒塌;设计的防撞装置能有效避免桥塔损伤,能削减碰撞力峰值、塔顶侧向位移、桥面位移及桥塔能量,同时保护斜拉桥与船舶. 展开更多
关键词 船-桥碰撞 数值模拟 附加质量 动力响应 防撞装置
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顶张力立管流致振动及碰撞实验研究
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作者 李效民 赵承杰 +3 位作者 顾洪禄 李福恒 郭海燕 初壮 《中国海洋大学学报(自然科学版)》 北大核心 2025年第6期140-151,共12页
针对顶张力立管在不同布置形式下的流致振动以及立管碰撞响应问题,本文对不同间距S下串联和并联布置顶张力立管进行了试验研究。试验基于光纤布拉格光栅(Fiber Bragg grating,FBG)应变传感器采集的立管弯曲应变数据,采用模态叠加法重构... 针对顶张力立管在不同布置形式下的流致振动以及立管碰撞响应问题,本文对不同间距S下串联和并联布置顶张力立管进行了试验研究。试验基于光纤布拉格光栅(Fiber Bragg grating,FBG)应变传感器采集的立管弯曲应变数据,采用模态叠加法重构立管位移响应,并对立管未碰撞和碰撞时的位移响应和频率响应特性进行了详细分析。结果表明:并联布置的立管流致振动轨迹不对称,且紧密排列时立管横流向位移增大,同时碰撞概率增加,而串联布置的上游立管在横流向上的最大位移小于下游立管;立管碰撞时,碰撞力及频率振幅变化规律受到立管间距和流速的双重影响;在S=3D(D为立管外径)时,碰撞力随着流速的增大而减小,而在S=2D时,碰撞力的大小随着流速的增大而增大;横流向频率振幅在碰撞前后的变化同管距S和流速均相关,而顺流向频率振幅则与流速正相关。 展开更多
关键词 顶张力立管 涡激振动 流致振动 碰撞响应 碰撞力
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高速公路团雾区驾驶特性分析与碰撞风险评价
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作者 吴付威 李育隆 +2 位作者 马勇 王畅 张智 《中国安全科学学报》 北大核心 2025年第5期124-134,共11页
为降低高速公路团雾环境下的交通事故风险,将高速公路团雾区划分为过渡区和冲突区,设计并开展驾驶模拟试验。首先,采用方差分析(ANOVA)、非参数检验等方法分析驾驶人在2个区域中的驾驶行为;然后,利用Pearson相关性分析探索过渡区与冲突... 为降低高速公路团雾环境下的交通事故风险,将高速公路团雾区划分为过渡区和冲突区,设计并开展驾驶模拟试验。首先,采用方差分析(ANOVA)、非参数检验等方法分析驾驶人在2个区域中的驾驶行为;然后,利用Pearson相关性分析探索过渡区与冲突区之间的驾驶行为指标关联特性;最后,通过二元Logistics回归模型挖掘驾驶行为对碰撞风险的影响机制。结果表明:在过渡区,驾驶经验与能见度变化率对速度标准差和内边界速度有显著影响;相比于新手驾驶人,熟练驾驶人速度标准差降低36.8%,内边界速度高13.5%;能见度变化率对速度标准差和内边界速度有统计学差异,不同能见度变化率对应的内边界速度和速度标准差不同。在冲突区,碰撞时间(TTC)与能见度呈显著正相关,避险反应时间与能见度呈显著负相关;TTC、避险反应时间及碰撞率均与冲突距离呈显著负相关;过渡区速度调整行为会显著影响冲突区的碰撞风险。 展开更多
关键词 高速公路 团雾 驾驶模拟 驾驶行为 碰撞风险
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基于智能算法的舰船避碰行动策略技术研究
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作者 苏娜 周雪芳 《舰船科学技术》 北大核心 2025年第6期149-153,共5页
快速且准确地制定舰船避碰行动方案对保证舰船安全及作战能力具有重要意义。本文将智能算法应用到舰船避碰行动策略制定中,从环境适应性、复杂场景处理能力以及实时性等3个方面对遗传算法、粒子群优化算法以及神经网络算法进行比较,以... 快速且准确地制定舰船避碰行动方案对保证舰船安全及作战能力具有重要意义。本文将智能算法应用到舰船避碰行动策略制定中,从环境适应性、复杂场景处理能力以及实时性等3个方面对遗传算法、粒子群优化算法以及神经网络算法进行比较,以避碰成功率、避碰时间、收敛速度为指标,对多种智能算法进行仿真分析,结果表明GA-PSO算法优于其他算法,提出了基于GA-PSO的舰船避碰行动策略。 展开更多
关键词 GA-PSO 避碰 舰船 行动策略
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