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Multi-target neural circuit reconstruction and enhancement in spinal cord injury 被引量:2
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作者 Lingyun Cao Siyun Chen +2 位作者 Shuping Wang Ya Zheng Dongsheng Xu 《Neural Regeneration Research》 2026年第3期957-971,共15页
After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the tim... After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the timing of interventions,combined with the limitations of current methods.To address these challenges,various techniques have been developed to aid in the repair and reconstruction of neural circuits at different stages of injury.Notably,neuromodulation has garnered considerable attention for its potential to enhance nerve regeneration,provide neuroprotection,restore neurons,and regulate the neural reorganization of circuits within the cerebral cortex and corticospinal tract.To improve the effectiveness of these interventions,the implementation of multitarget early interventional neuromodulation strategies,such as electrical and magnetic stimulation,is recommended to enhance functional recovery across different phases of nerve injury.This review concisely outlines the challenges encountered following spinal cord injury,synthesizes existing neurostimulation techniques while emphasizing neuroprotection,repair,and regeneration of impaired connections,and advocates for multi-targeted,task-oriented,and timely interventions. 展开更多
关键词 multi-targets nerve root magnetic stimulation neural circuit NEUROMODULATION peripheral nerve stimulation RECONSTRUCTION spinal cord injury task-oriented training TIMING transcranial magnetic stimulation
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Current development and future prospects of multi-target assignment problem:A bibliometric analysis review 被引量:1
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作者 Shuangxi Liu Zehuai Lin +1 位作者 Wei Huang Binbin Yan 《Defence Technology(防务技术)》 2025年第1期44-59,共16页
The multi-target assignment(MTA)problem,a crucial challenge in command control,mission planning,and a fundamental research focus in military operations,has garnered significant attention over the years.Extensively stu... The multi-target assignment(MTA)problem,a crucial challenge in command control,mission planning,and a fundamental research focus in military operations,has garnered significant attention over the years.Extensively studied across various domains such as land,sea,air,space,and electronics,the MTA problem has led to the emergence of numerous models and algorithms.To delve deeper into this field,this paper starts by conducting a bibliometric analysis on 463 Scopus database papers using CiteSpace software.The analysis includes examining keyword clustering,co-occurrence,and burst,with visual representations of the results.Following this,the paper provides an overview of current classification and modeling techniques for addressing the MTA problem,distinguishing between static multi-target assignment(SMTA)and dynamic multi-target assignment(DMTA).Subsequently,existing solution algorithms for the MTA problem are reviewed,generally falling into three categories:exact algorithms,heuristic algorithms,and machine learning algorithms.Finally,a development framework is proposed based on the"HIGH"model(high-speed,integrated,great,harmonious)to guide future research and intelligent weapon system development concerning the MTA problem.This framework emphasizes application scenarios,modeling mechanisms,solution algorithms,and system efficiency to offer a roadmap for future exploration in this area. 展开更多
关键词 multi-target assignment Offensive and defensive confrontation Cooperative operation Modeling mechanism Solution algorithm CiteSpace analysis
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A fast-aware multi-target response prediction approach and its application in aeronautical engineering
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作者 Minzhao ZHANG Junliang DING Bin LI 《Chinese Journal of Aeronautics》 2025年第5期443-457,共15页
Response prediction is a fundamental yet challenging task in aeronautical engineering,requiring an accurate selection of sensor positions correlated with the target responses to achieve precise predictions. Unfortunat... Response prediction is a fundamental yet challenging task in aeronautical engineering,requiring an accurate selection of sensor positions correlated with the target responses to achieve precise predictions. Unfortunately, in large-scale structures, the rigorous selection of reliable sensor candidates for multi-target responses remains largely unexplored. In this paper, we propose a flexible and generalized framework for selecting the most relevant sensors to the multi-target response and predicting the target response, referred to as the Fast-aware Multi-Target Response Prediction(FMTRP) approach in the spirit of divide-and-conquer. Specifically, first, a multi-task learning module is designed to predict multi-point response tasks at the same time. Simultaneously, we meticulously devise adaptive mechanisms to facilitate loss-term reweighting and encourage prioritization of challenging tasks in multiple prediction tasks. Second, to ensure ease of interpretation,we introduce a hybrid penalty to select sensors at the group-sparsity, individual-sparsity and element-sparsity levels. Finally, due to the substantial number of candidate sensors posing a significant computational burden, we develop a more efficient search strategy and support computation to make the proposed approach applicable in practice, leading to substantial runtime improvements. Extensive experiments on aircraft standard model response datasets and large airliner test flight datasets validate the effectiveness of the proposed approach in identifying sensor locations and simultaneously predicting responses at multiple points. Compared to state-of-the-art methods,the proposed approach achieves an accuracy of over 99% in sinusoidal excitation and exhibits the shortest runtime(3.514 s). 展开更多
关键词 multi-target response prediction Sensor placement Feature selection Dynamic task prioritization Fast implementation
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Low-complexity multi-target localization via multi-BS sensing
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作者 Yinxiao Zhuo Zhaocheng Wang 《Digital Communications and Networks》 2025年第4期1140-1148,共9页
Integrated Sensing and Communication(ISAC)is envisioned as a promising technology for Sixth-Generation(6G)wireless communications,which enables simultaneous high-rate communication and high-precision target localizati... Integrated Sensing and Communication(ISAC)is envisioned as a promising technology for Sixth-Generation(6G)wireless communications,which enables simultaneous high-rate communication and high-precision target localization.Compared to independent sensing and communication modules,dual-function ISAC could leverage the strengths of both communication and sensing in order to achieve cooperative gains.When considering the communication core network,ISAC system facilitates multiple communication devices to collaborate for networked sensing.This paper investigates such kind of cooperative ISAC systems with distributed transmitters and receivers to support non-connected and multi-target localization.Specifically,we introduce a Time of Arrival(TOA)based multi-target localization scheme,which leverages the bi-static range measurements between the transmitter,target,and receiver channels in order to achieve elliptical localization.To obtain the low-complexity localization,a two-stage search-refine localization methodology is proposed.In the first stage,we propose a Successive Greedy Grid-Search(SGGS)algorithm and a Successive-Cancellation-List Grid-Search(SCLGS)algorithm to address the Measurement-to-Target Association(MTA)problem with relatively low computational complexity.In the second stage,a linear approximation refinement algorithm is derived to facilitate high-precision localization.Simulation results are presented to validate the effectiveness and superiority of our proposed multi-target localization method. 展开更多
关键词 Integrated sensing and communication multi-target localization Measurement-to-target association problem Bi-static range measurement Low complexity
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Exploration of New Methods of Lightning Strike Risk Assessment in Wind Farms
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作者 Weixiang FENG Yijun LONG +3 位作者 Xiaoqing PAN Ruiliang CHEN Chunliang ZHANG Hui YANG 《Meteorological and Environmental Research》 2025年第1期44-48,共5页
In the past,the lightning strike risk assessment of wind farms mainly referred to the Lightning Protection Part 2:Risk Management(IEC 62305-2-2010)and the Lightning Protection of Wind Energy System(IEC 61400-24-2019)b... In the past,the lightning strike risk assessment of wind farms mainly referred to the Lightning Protection Part 2:Risk Management(IEC 62305-2-2010)and the Lightning Protection of Wind Energy System(IEC 61400-24-2019)based on protection angle method.In fact,the basic idea of the two is the same,that is,the source of the lightning fan is replaced by S1-S4 of the former lightning building with the latter ND-NDJ.According to the above method of wind farm evaluation,it has been proved that the practice can not achieve good results.Taking offshore wind farm as an example,this paper introduces a new method of establishing six evaluation indicators to determine the risk level according to the new technology and compliance principle of regional lightning protection(semi-circular method),which can be used for reference by wind farm technicians. 展开更多
关键词 Sea and land wind electric field Lightning strike risk assessment Compliance principle New evaluation method
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伸展盆地中的变换走滑构造及其油气地质意义
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作者 刘晓林 景安语 +1 位作者 武云云 李伟 《海洋地质前沿》 北大核心 2026年第1期11-24,共14页
变换构造在伸展盆地内普遍发育,变换走滑构造作为其中的一种特殊类型,是为保持区域或局部应变守恒、传递伸展断层之间的位移,发育在不同伸展断层域之间的具有明显水平位移的被动走滑构造,形成于非走滑应力体制下。变换走滑构造在中国东... 变换构造在伸展盆地内普遍发育,变换走滑构造作为其中的一种特殊类型,是为保持区域或局部应变守恒、传递伸展断层之间的位移,发育在不同伸展断层域之间的具有明显水平位移的被动走滑构造,形成于非走滑应力体制下。变换走滑构造在中国东部伸展盆地中普遍发育、类型多样,依据是否形成明显的走滑断裂可划分为变换走滑断层和变换走滑带,其类型与两侧断层伸展差异大小有关,进一步依据两侧断层的倾向,每类又可划分为倾向相反型、倾向相同型和倾向复杂型3个亚类。变换走滑构造对油气成藏具有重要的控制作用,可以为伸展盆地内构造圈闭解释判识提供依据,变换走滑构造导致局部地层的弯曲变形,控制了古地貌或微古地貌的分布,进而对沉积储层的发育展布具有一定的控制作用;变换走滑构造可以作为有利的油气聚集区带,也可以对油气分布起到分隔作用。 展开更多
关键词 变换走滑构造 类型划分 控藏作用 伸展盆地
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人工智能在断裂识别中的应用——以塔里木盆地哈拉哈塘地区奥陶系走滑断裂的识别为例
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作者 罗枭 韩龙 +7 位作者 赵宽志 任欢颂 艾明波 萨阿代提古丽·如则 杨美纯 苏洲 蔡泉 张驰 《天然气地球科学》 北大核心 2026年第1期178-190,共13页
随着人工智能技术的快速发展,其在地质勘探领域的应用也逐渐展现出巨大潜力。传统的断裂识别方法主要依赖于地质学家的经验和人工判读。这种方法不仅效率低下,而且容易受到主观因素的影响,难以实现大规模数据的高效处理。为解决这一问题... 随着人工智能技术的快速发展,其在地质勘探领域的应用也逐渐展现出巨大潜力。传统的断裂识别方法主要依赖于地质学家的经验和人工判读。这种方法不仅效率低下,而且容易受到主观因素的影响,难以实现大规模数据的高效处理。为解决这一问题,以塔里木盆地哈拉哈塘地区走滑断裂识别为例,探索了人工智能在走滑断裂识别中的应用效果及可行性。结果表明:哈拉哈塘地区主要发育2组高角度走滑断裂系统,北北东和北北西向,两者在平面上呈X型相互交切关系。基于区内高精度三维地震资料的预处理成果,并利用卷积神经网络(CNN)深度学习算法及U-Net架构模型对研究区断裂进行自动化识别与分类实验。在明显消除随机噪声影响的背景下,上述算法对主干断裂、分支断裂及其组合关系识别清晰。通过对实验结果的分析,验证了深度学习模型在提升走滑断裂识别精度与效率上的显著优势,为地质勘探工作提供了新的技术手段。 展开更多
关键词 人工智能 断裂识别 走滑断裂 属性体提取 哈拉哈塘 奥陶系
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顺北—顺南地区深层碳酸盐岩走滑断裂结构特征及其形成的主控因素分析
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作者 吴孔友 杨言军 +2 位作者 刘寅 洪梅 汪必峰 《浙江大学学报(理学版)》 北大核心 2026年第1期97-108,共12页
塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有... 塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有研究成果,通过野外相似露头踏勘,结合地震、岩心等资料,利用高精度三维地震数据体走滑断裂精细刻画、地震属性体走滑断裂体系识别、物理模拟实验、应力场数值模拟等技术方法,分析了走滑断裂的结构特征,并对其形成的主控因素进行了归纳总结。研究发现,顺北—顺南地区深层走滑断裂的空间结构主要表现为“平面沿走向分段、剖面分层变形”的特征,在平面上主断裂可划分为张扭段、压扭段、直立段,三者交替出现,在剖面上以中下奥陶统顶界面(T74)为界,将断裂分为深层和浅层系统,深、浅层断裂纵向叠置,分层特征明显。将内部结构划分为“滑动破碎带—诱导裂缝带”二元结构,二者差异明显,特征相异。多期构造活动、应力分布、断裂活动强度、地层岩性和后期的胶结充填作用均可影响断裂带的二元结构。 展开更多
关键词 塔里木盆地 碳酸盐岩 走滑断裂 结构特征 控制因素
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风机电加热融冰叶片的雷击接闪特性
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作者 王欢 胡琴 +2 位作者 舒立春 蒋兴良 唐芳纯 《电工技术学报》 北大核心 2026年第3期1026-1039,共14页
风机叶片的覆冰和雷击问题突出,电加热融冰技术能较好地解决叶片覆冰问题,但电加热融冰叶片(简称融冰叶片)的雷击接闪问题还有待深入研究。该文根据叶片覆冰防护区域设计了融冰叶片,并遵循相似性理论,在雪峰山国家野外站搭建了缩比风机... 风机叶片的覆冰和雷击问题突出,电加热融冰技术能较好地解决叶片覆冰问题,但电加热融冰叶片(简称融冰叶片)的雷击接闪问题还有待深入研究。该文根据叶片覆冰防护区域设计了融冰叶片,并遵循相似性理论,在雪峰山国家野外站搭建了缩比风机叶片长间隙放电试验平台,研究了融冰叶片的雷击接闪特性,分析了接闪点的雷击概率,并与普通叶片进行对比。结果表明:融冰叶片的雷击接闪具有极性效应,导致在正极性雷击时接闪点及其概率分布更为分散。融冰叶片电热元件的雷击烧蚀损伤风险较为突出,其雷击概率与雷电的位置和极性、叶片状态有关;电热元件的雷击概率在雷电来自迎风面时最大(背风面时为0)、正极性雷击或叶片旋转时明显更高。与普通叶片相比,融冰叶片电热元件的邻域电场会产生畸变和屏蔽引下线电场,导致其接闪器及叶身的雷击概率下降,接闪点转移至电热元件,尤其是其边缘处。该文试验结果明晰了融冰叶片的雷击风险,并可为其防雷设计提供指导。 展开更多
关键词 风机叶片 电加热融冰 雷击放电 接闪特性 雷击概率 失效机制
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一种去除地层背景凸显缝洞体结构的地震描述新方法——以塔里木盆地富满地区YM区块为例
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作者 王彭 桂志鹏 +5 位作者 尹朋博 李会元 王青红 智德光 王雨 张军华 《石油物探》 北大核心 2026年第1期156-165,共10页
缝洞体核部识别是缝洞型储层描述的核心环节之一。由于缝洞体内部的孔、缝、洞和流体等与断层相互叠合,情况复杂,仅依靠地震相难以对缝洞体进行有效且准确的解释。传统的相干、曲率、最大似然等属性算法已无法满足当前油气勘探开发对缝... 缝洞体核部识别是缝洞型储层描述的核心环节之一。由于缝洞体内部的孔、缝、洞和流体等与断层相互叠合,情况复杂,仅依靠地震相难以对缝洞体进行有效且准确的解释。传统的相干、曲率、最大似然等属性算法已无法满足当前油气勘探开发对缝洞体识别精度的需求。针对塔里木盆地富满地区YM区块复杂缝洞体储层特点,提出了一套全新的缝洞体描述方法。首先,根据地震资料的精细解释地震数据确定储层的顶界面、底界面,从原始地震数据中提取目的层位体,形成地层切片体;利用空间-波数域滤波技术去除地层切片体的地层背景;然后,提取缝洞体梯度结构张量第一特征值,利用阈值和幅值控制能量脊,以此识别缝洞体核部;最后,融合识别结果与地层切片体,并将其内嵌到原始地震数据中,得到最终的缝洞体描述数据体。将该方法应用于W5井区的储层预测,识别的缝洞体核部与井震数据吻合度较高;此外,在应用于W2井区时,成功预测出3个有利靶点。该方法的应用结果表明,去除地层背景、凸显缝洞体结构的地震描述方法能够对复杂缝洞体实现有效描述,具有一定的推广应用价值。 展开更多
关键词 塔里木盆地 缝洞体 走滑断层 空间-波数域滤波 特征值 核部追踪
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Pricing Multi-Strike Quanto Call Options on Multiple Assets with Stochastic Volatility, Correlation, and Exchange Rates
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作者 Boris Ter-Avanesov Gunter Meissner 《Applied Mathematics》 2025年第1期113-142,共30页
Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign cur... Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign currencies each with a different strike price in the payoff function. We carry out a comparative performance analysis of different stochastic volatility (SV), stochastic correlation (SC), and stochastic exchange rate (SER) models to determine the best combination of these models for Monte Carlo (MC) simulation pricing. In addition, we test the performance of all model variants with constant correlation as a benchmark. We find that a combination of GARCH-Jump SV, Weibull SC, and Ornstein Uhlenbeck (OU) SER performs best. In addition, we analyze different discretization schemes and their results. In our simulations, the Milstein scheme yields the best balance between execution times and lower standard deviations of price estimates. Furthermore, we find that incorporating mean reversion into stochastic correlation and stochastic FX rate modeling is beneficial for MC simulation pricing. We improve the accuracy of our simulations by implementing antithetic variates variance reduction. Finally, we derive the correlation risk parameters Cora and Gora in our framework so that correlation hedging of quanto options can be performed. 展开更多
关键词 Quanto Option Multi-strike Option Stochastic Volatility (SV) Stochastic Correlation (SC) Stochastic Exchange Rates (SER) CORA GORA Correlation Risk
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基于LLS监测数据的山区微地形落雷分布差异及影响因素分析
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作者 余田野 张科杰 贺姗 《暴雨灾害》 2026年第1期121-129,共9页
为精细化研究山区不同位置的落雷分布差异,首先提出了落雷系数和落雷密度系数的概念,用其表征不同山区地形落雷密集程度(频次和密度),利用闪电击距理论,推导了山顶、山腰和山谷3种微地形的落雷系数和落雷密度系数计算公式;然后分析地形... 为精细化研究山区不同位置的落雷分布差异,首先提出了落雷系数和落雷密度系数的概念,用其表征不同山区地形落雷密集程度(频次和密度),利用闪电击距理论,推导了山顶、山腰和山谷3种微地形的落雷系数和落雷密度系数计算公式;然后分析地形高度、山体坡度2个地理参数以及电流强度对山区微地形落雷分布的影响。最后基于近10 a(2015—2024年)湖北大洪山地区极低频/低频(Very Low Frequency/Low Frequency,VLF/LF)雷电定位系统(Lighting Location System, LLS)闪电监测数据对公式进行了实例验证。结果表明:山顶对闪电具有吸引作用,导致其落雷系数、落雷密度系数均为最大,山谷对闪电具有屏蔽作用,其落雷系数、落雷密度系数最小,山腰落雷系数、落雷密度系数介于两者之间;地形高度越大,不同微地形的落雷系数、落雷密度系数差异越小,并逐渐趋于稳定;随着山体坡度的增加,不同微地形的落雷系数差异越大,而落雷密度系数呈减小趋势;电流强度越大,不同微地形落雷系数、落雷密度系数差异越大。实例验证显示,试验区山区微地形的落雷分布特征与上述结果吻合。本研究结果可为山区精细化雷电防护工程设计和雷电灾害风险评估等防雷提供参考。 展开更多
关键词 雷电定位系统 山区微地形 落雷系数 落雷密度系数 雷电密度
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近走滑断层山岭隧道全过程地震响应研究
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作者 刘中宪 刘佳乔 +1 位作者 张海 黄振恩 《东南大学学报(自然科学版)》 北大核心 2026年第1期61-69,共9页
充分结合间接边界元法(IBEM)在处理断层-大尺度复杂场地问题中的独特优势,以及有限元法(FEM)在模拟工程结构非线性地震响应方面的灵活性,提出了一种用于模拟断层破裂—场地放大—结构破坏全过程地震响应的IBEM-FEM耦合方法。通过模型试... 充分结合间接边界元法(IBEM)在处理断层-大尺度复杂场地问题中的独特优势,以及有限元法(FEM)在模拟工程结构非线性地震响应方面的灵活性,提出了一种用于模拟断层破裂—场地放大—结构破坏全过程地震响应的IBEM-FEM耦合方法。通过模型试算,并与IBEM模拟结果进行对比,验证了该耦合方法的准确性。进一步以近走滑断层山岭隧道模型为例,基于该耦合方法,研究了在设定震级Mw6.7下,不同断层破裂速度对山岭隧道结构地震响应的影响。结果表明,随着断层破裂速度的增加,隧道等效塑性应变以及损伤范围和程度均显著加剧。尤其在超剪切破裂条件下,隧道空间分布呈现出更强的不均匀性。因此,在近断层区域,山岭隧道的抗震设计应特别关注并加强对超剪切破裂的防范,提升其在极端地震条件下的适应性与抗震韧性。 展开更多
关键词 山岭隧道 三维IBEM-FEM耦合法 走滑断层 全过程地震响应 超剪切破裂
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琼海凸起及周缘潜山逆冲-走滑断裂特征与火山岩储层裂缝成因研究
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作者 单玄龙 耿旸 李昂 《石油科学通报》 2026年第1期14-27,共14页
琼海凸起及周缘潜山位于珠江口盆地珠三坳陷,是南海北部油气勘探重点区域。该区火山岩储层受裂缝改造作用显著,为厘清成因机制,研究结合高精度三维地震资料、钻井数据及薄片观察展开分析。结果表明,研究区断裂分两期发育:燕山早-中期NW... 琼海凸起及周缘潜山位于珠江口盆地珠三坳陷,是南海北部油气勘探重点区域。该区火山岩储层受裂缝改造作用显著,为厘清成因机制,研究结合高精度三维地震资料、钻井数据及薄片观察展开分析。结果表明,研究区断裂分两期发育:燕山早-中期NW向挤压形成NE向叠瓦式逆冲断层(喜山早期活化);燕山晚期左旋走滑形成含纯走滑、张扭、压扭段的NNE向断裂体系(喜山中期活化)。裂缝同步发育两期,其中逆冲断层上盘近断层区(如WC13-I井)、走滑带压扭段(如WC19-A井)及张扭段(如WC13-M井)裂缝最密集。具体而言,逆冲断层通过挤压使上盘岩层剪切破裂,走滑断裂不同分段因应力差异形成差异化裂缝网络,喜山期应力转换进一步活化早期裂缝,最终形成的裂缝网络为油气运移提供有效通道,为该区勘探提供依据。 展开更多
关键词 琼海凸起 火山岩储层 逆冲断裂 走滑断裂 裂缝发育规律 珠三坳陷 油气储层
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MULTI-FIGHTER COORDINATED MULTI-TARGET ATTACK SYSTEM 被引量:7
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作者 耿延洛 姜长生 李伟浩 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期18-23,共6页
A definition of self-determined priority is used in airfight decision firstly. A scheme of grouping the whole fighters is introduced, and the principle of target assignment and fire control is designed. Based on the ... A definition of self-determined priority is used in airfight decision firstly. A scheme of grouping the whole fighters is introduced, and the principle of target assignment and fire control is designed. Based on the neutral network, the decision algorithm is derived and the whole coordinated decision system is simulated. Secondly an algorithm for missile-attacking area is described and its calculational result is obtained under initial conditions. Then the attacking of missile is realized by the proportion guidance. Finally, a multi-target attack system. The system includes airfight decision, estimation of missile attack area and calculation of missile attack procedure. A digital simulation demonstrates that the airfight decision algorithm is correct. The methods have important reference values for the study of fire control system of the fourth generation fighter. 展开更多
关键词 multi-target attack coordinated airfight decision missile attack area priority fire control
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Technology Research on Lightning Strike Risk Evaluation of a Cable Car 被引量:3
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作者 扈勇 冯鹤 《Agricultural Science & Technology》 CAS 2015年第10期2318-2321,共4页
According to structure function and lightning damage of a cable car, a feasible method of lightning strike risk evaluation for a cable car was put forward based on the evaluation model and evaluation method in the sta... According to structure function and lightning damage of a cable car, a feasible method of lightning strike risk evaluation for a cable car was put forward based on the evaluation model and evaluation method in the standard IEC62305-2. According to the difference between common buildings and cable cars, problems of height non-uniformity of equivalent section caused by inclination of the cable car and diversity of lightning activity regularity caused by the large area were resolved, and expected annual average frequency of lightning strike was calculated using three dimensional graphic approach and regional lightning characteristic analysis. Based on different types of damage process and loss consequences, according to interception effect against lightning invasion of the lightning protection measures and the method of probability selection proposed in the standard, the probability of casu- alty caused by direct lightning strike in a cable car and a waiting area as well as probabilities of casualty caused by failure of electronic information systems were cal- culated. 展开更多
关键词 Cable cars Lightning strike risk evaluation Technology research
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走滑型断溶体形成机制与油气成藏研究进展
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作者 王露露 代宗仰 +3 位作者 李阳 高洋 任铌 郭子家 《地质科技通报》 北大核心 2026年第1期95-109,共15页
断溶体在国内多数盆地普遍发育,其资源量巨大,已经成为地学界研究的热点课题。但由于其埋藏深、勘探难度大,对断溶体的圈闭划分、形成机制、发育控制因素观点不一,亟需形成一致的认识。首先回顾了断溶体的基本概念,指出其具有埋藏深、... 断溶体在国内多数盆地普遍发育,其资源量巨大,已经成为地学界研究的热点课题。但由于其埋藏深、勘探难度大,对断溶体的圈闭划分、形成机制、发育控制因素观点不一,亟需形成一致的认识。首先回顾了断溶体的基本概念,指出其具有埋藏深、非均质性强、流体性质差异大等特点,并强调了走滑断层在油气储集和运移中的重要作用。通过对塔里木盆地顺北地区及其他地区的地质数据进行分析,揭示了断溶体的圈闭类型、形成机制及其控藏因素。研究认为走滑断层的分段性、溶蚀流体的活动以及烃类的及时侵位对断溶体油气藏的发育至关重要。此外,研究了大气淡水、热液流体和烃类流体在储层改造中的作用,及如何共同影响断溶体油气藏的形成和分布。总结了断溶体油气藏的成藏模式。本研究有助于开拓新的油气勘探领域和方向。 展开更多
关键词 断溶体 圈闭类型 形成机制 控藏作用 走滑断层 成藏模式
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基于局部模型的船艇结构碰撞试验方法研究
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作者 潘柏衡 方馨悦 +1 位作者 梁晓锋 董安锐 《船海工程》 北大核心 2026年第1期117-122,共6页
为确定船艇防直接碰撞的能力,规范船艇实船碰撞试验流程,设计基于局部模型的实船碰撞试验方案,利用DNV规范确定撞击船与被撞船的速度质量转换关系,选取被撞船侧壁典型结构薄弱位置,构建被撞船的1:1局部模型,并开展实船碰撞试验,试验确... 为确定船艇防直接碰撞的能力,规范船艇实船碰撞试验流程,设计基于局部模型的实船碰撞试验方案,利用DNV规范确定撞击船与被撞船的速度质量转换关系,选取被撞船侧壁典型结构薄弱位置,构建被撞船的1:1局部模型,并开展实船碰撞试验,试验确保模拟撞击过程中的能量耗散与实际撞击的能量耗散一致,且均被侧壁材料的塑性变形所吸收。试验结果表明,通过此试验方法可直接观察样件碰撞后破损情况以确定船艇结构防直接碰撞能力,从而支撑全船碰撞能力的评估。实船碰撞试验的设计思路及关键实施步骤可为组织同类试验提供参考。 展开更多
关键词 局部模型试验 撞击 结构 耗散能一致 试验设计
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考虑多重雷击的10 kV线路避雷器雷击失效率计算方法
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作者 张佩瑄 韩永霞 +3 位作者 施剑峰 胡上茂 李志峰 宋坤宇 《广东电力》 北大核心 2026年第1期96-105,共10页
雷电多回击地闪引起配电线路短时间内遭受多重雷击,容易造成避雷器失效。针对国内外较少考虑多重雷击下配电线路避雷器的参数设计和选型,首先统计分析广东地区2014—2023年地闪参数及多回击地闪占比,提出雷电流幅值的概率分布和地闪密... 雷电多回击地闪引起配电线路短时间内遭受多重雷击,容易造成避雷器失效。针对国内外较少考虑多重雷击下配电线路避雷器的参数设计和选型,首先统计分析广东地区2014—2023年地闪参数及多回击地闪占比,提出雷电流幅值的概率分布和地闪密度分布。其次,结合雷电参数统计结果及10 kV配电线路雷电过电压仿真结果,提出直击雷和感应过电压下线路避雷器雷击失效率的计算方法。最后,基于该方法对比分析不同通流能力避雷器雷击失效率差异,结果表明:珠三角地区某10 km的10 kV线路安装D5型避雷器时年雷击失效数量不超过2.2只,较D3型降低61.11%,可有效提升配电网安全运行水平。考虑了广东省实际雷电参数、多回击地闪占比及避雷器失效率的准确计算方法,可为配电网雷电防护工作提供更明确的理论指导和工程参考。 展开更多
关键词 多重雷击 线路避雷器 雷击失效率 雷电防护
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川东北五宝场地区须家河组致密砂岩储层走滑断裂带识别及其油气地质意义
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作者 王珍 曾令平 +4 位作者 章海燕 曾联波 宋东昇 文建军 李浩 《石油科学通报》 2026年第1期28-40,共13页
川东北地区须家河组致密砂岩储层天然气富集规律复杂,断裂体系对油气成藏具有重要控制作用。为明确该区断裂构造特征及其对天然气富集的影响,本研究基于三维地震数据和钻井资料,采用人工智能断层识别技术和构造解析方法,在川东北五宝场... 川东北地区须家河组致密砂岩储层天然气富集规律复杂,断裂体系对油气成藏具有重要控制作用。为明确该区断裂构造特征及其对天然气富集的影响,本研究基于三维地震数据和钻井资料,采用人工智能断层识别技术和构造解析方法,在川东北五宝场地区须家河组识别出NE-SW向雁列式走滑断裂带,对其构造变形特征、形成演化及控储控藏效应进行了研究。结果表明,该断裂带具有纵向分层的变形特征,在上奥陶统至下三叠统嘉陵江组表现为逆冲断层,在上三叠统须家河组表现为系列NNW-SSE向小型逆断层呈右阶雁列式排列的走滑断裂带。该断裂带经历了2期构造演化阶段,印支期-燕山期在SE-NW向持续构造挤压应力作用下,表现为逆冲断层活动;喜马拉雅期区域构造应力场发生转变,在NE-SW向水平挤压应力场作用下,早期形成的主干断层发生了左旋走滑活动,在须家河组形成了一系列呈NNW-SSE向右阶雁列式排布的走滑断裂带。须家河组雁列式断层与深部主干断层相互连通,沟通了须家河组储集层、龙潭组烃源岩与深部流体,形成“下强上弱”输导体系及“双源供烃”模式,同时对须家河组致密砂岩储层产生“溶蚀增孔”与“胶结破坏”双重改造作用,为须家河组致密储层差异演化和甜点储层的发育提供了良好的动力条件,是须家河组致密砂岩储层天然气富集和保存的有利场所。研究显示,走滑断裂带是川东北地区三叠系致密砂岩储层天然气的有利富集带,应重视该类目标区的天然气评价与勘探。 展开更多
关键词 须家河组 致密砂岩 走滑断裂带 人工智能 地质意义
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