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Digital Communications and Networks 2024年第3期10卷 620-630页

作者： Guanlin Wu Haipeng Wang Yu Liu you he Shenzhen International Graduate School Tsinghua UniversityShenzhen518071China Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen518055China Department of Electronic Engineering Tsinghua UniversityBeijing100084China

With the rapid growth of the maritime Internet of Things(IoT)devices for Maritime Monitor Services(MMS),maritime traffic controllers could not handle a massive amount of data in *** unmanned MMS,one of the key technologies is situation ***,the presence of slow-fast high maneuvering targets and track breakages due to radar blind zones make modeling the dynamics of marine multi-agents difficult,and pose significant challenges to maritime situation *** order to comprehend the situation accurately and thus offer unmanned MMS,it is crucial to model the complex dynamics of multi-agents using IoT big ***,previous methods typically rely on complex assumptions,are plagued by unstructured data,and disregard the interactions between multiple agents and the spatial-temporal correlations.A deep learning model,Graph Spatial-Temporal Generative Adversarial Network(GraphSTGAN),is proposed in this paper,which uses graph neural network to model unstructured data and uses STGAN to learn the spatial-temporal dependencies and *** experiments show the effectiveness and robustness of the proposed method.

关键词： Internet of things Multi-agents Graph neural network Maritime monitoring services

Density-based ship detection in SAR images:Extension to a self-similarity perspective

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Chinese Journal of Aeronautics 2024年第3期37卷 168-180页

作者： Xueqian WANG Gang LI Zhizhuo JIANG Yu LIU you he Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China

Nonlocal self-similarity is an important property of Synthetic Aperture Radar(SAR)images to characterize the repetitiveness of features embodied by SAR images within nonlocal areas and has been used for enhancement of SAR *** SAR ship detectors often independently handle small sub-images cropped from a large marine SAR image and do not exploit the nonlocal self-similarity *** this paper,we propose a new ship detector from the perspective of nonlocal self-similarity in SAR images to improve the ship detection performance,basically including three stages:prescreening,intra-cue calculation,and inter-cue *** the prescreening stage,we design a new Histogram-based Density(HD)feature to rapidly select candidate sub-images potentially containing ship targets from a large SAR *** the intra-cue calculation stage,target cues within a single candidate sub-image are *** the inter-cue calculation stage,thanks to the nonlocal self-similarity among different candidate sub-images in terms of density features,we innovatively extract a weighted superpixel-HD map to obtain accumulated intracues across all the candidate ***,for each candidate sub-image,we fuse its inter-cue and intra-cue to obtain final detection *** results based on real SAR images show that our newly proposed method provides a better target-to-clutter contrast and ship detection performance than those of other state-of-the-art detection approaches.

关键词： Ship detection Synthetic aperture radar(SAR) Density Self-similarity Histogram

Hydrocarbon gas huff-n-puff optimization of multiple horizontal wells with complex fracture networks in the M unconventional reservoir

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Petroleum Science 2024年第2期21卷 1018-1031页

作者： Hao-Chuan Zhang Yong Tang you-Wei he Yong Qin Jian-Hong Luo Yu Sun Ning Wang De-Qiang Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina CNPC Research Institute of Petroleum Exploration&Development Beijing100083China Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina State Key Laboratory of Offshore Oil Exploitation CNOOC Research Institute Co.LtdBeijing100027China

The oil production of the multi-fractured horizontal wells(MFHWs) declines quickly in unconventional oil reservoirs due to the fast depletion of natural energy. Gas injection has been acknowledged as an effective method to improve oil recovery factor from unconventional oil reservoirs. Hydrocarbon gas huff-n-puff becomes preferable when the CO_(2) source is limited. However, the impact of complex fracture networks and well interference on the EOR performance of multiple MFHWs is still unclear. The optimal gas huff-n-puff parameters are significant for enhancing oil recovery. This work aims to optimize the hydrocarbon gas injection and production parameters for multiple MFHWs with complex fracture networks in unconventional oil reservoirs. Firstly, the numerical model based on unstructured grids is developed to characterize the complex fracture networks and capture the dynamic fracture ***, the PVT phase behavior simulation was carried out to provide the fluid model for numerical simulation. Thirdly, the optimal parameters for hydrocarbon gas huff-n-puff were obtained. Finally, the dominant factors of hydrocarbon gas huff-n-puff under complex fracture networks are obtained by fuzzy mathematical method. Results reveal that the current pressure of hydrocarbon gas injection can achieve miscible displacement. The optimal injection and production parameters are obtained by single-factor analysis to analyze the effect of individual parameter. Gas injection time is the dominant factor of hydrocarbon gas huff-n-puff in unconventional oil reservoirs with complex fracture networks. This work can offer engineers guidance for hydrocarbon gas huff-n-puff of multiple MFHWs considering the complex fracture networks.

关键词： Unconventional oil reservoir Complex fracture network Hydrocarbon gas huff-n-puff Parameter optimization Numerical simulation

Generation and regulation of electromagnetic pulses generated by femtosecond lasers interacting with multitargets

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Nuclear Science and Techniques 2024年第1期35卷 96-107页

作者： Ya-Dong Xia De-Feng Kong Qiang-you he Zhen Guo Dong-Jun Zhang Tong Yang Hao Cheng Yu-Ze Li Yang Yan Xiao Liang Ping Zhu Xing-Long Xie Jian-Qiang Zhu Ting-Shuai Li Chen Lin Wen-Jun Ma Xue-Qing Yan State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871China Beijing Laser Acceleration Innovation Center Beijing 101407China Institute of Guangdong Laser Plasma Technology Guangzhou 510540China National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and FineChinese Academy of SciencesShanghai 201800China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Ultrashort and powerful laser interactions with a target generate intense wideband electromagnetic pulses(EMPs).In this study,we report EMPs generated by the interactions between petawatt(30 fs,1.4×10^(20) W/cm^(2))femtosecond(fs)lasers with metal flat,plastic flat,and plastic nanowire-array(NWA)*** analyses are conducted on the EMPs in terms of their spatial distribution,time and frequency domains,radiation energy,and *** results indicate that EMPs from metal targets exhibit larger amplitudes at varying angles than those generated by other types of targets and are enhanced significantly for NWA *** a plastic target holder and increasing the laser focal spot can significantly decrease the radiation energy of the ***,the composite shielding materials indicate an effective shielding effect against *** simulation results show that the NWA targets exert a collimating effect on thermal electrons,which directly affects the distribution of *** study provides guidance for regulating EMPs by controlling the laser focal spot,target parameters,and target rod material and is beneficial for electromagnetic-shielding design.

关键词： Electromagnetic pulses Laser plasma interaction Electromagnetic shielding Electron distribution

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数字鸿沟对农村老年人社会参与的影响

华南农业大学学报（社会科学版） 2024年第3期23卷 48-60页

作者：崔钰鹏何有世江苏大学管理学院江苏镇江212013

在数字时代与老龄化社会的双重背景下,数字鸿沟对农村老年人社会参与造成的影响亟待关注。基于2020年中国家庭追踪调查数据,运用层次回归和中介效应检验法实证研究数字鸿沟对农村老年人社会参与的影响及作用机制。研究发现:数字鸿沟对... 详细信息

在数字时代与老龄化社会的双重背景下,数字鸿沟对农村老年人社会参与造成的影响亟待关注。基于2020年中国家庭追踪调查数据,运用层次回归和中介效应检验法实证研究数字鸿沟对农村老年人社会参与的影响及作用机制。研究发现:数字鸿沟对农村老年人社会参与有显著负向影响,其中使用沟与知识沟负向作用于农村老年人社会参与,接入沟则正向作用于农村老年人社会参与。数字鸿沟主要通过健康状况、文化资本和社会信任3个渠道影响农村老年人社会参与,且健康状况、文化资本和社会信任均正向作用于农村老年人社会参与。异质性分析发现,相较于女性,数字鸿沟对农村男性老年人社会参与的负向影响效果更大,但在政治参与方面则相反。研究结论可为提升农村老年人社会参与水平、积极应对人口老龄化危机提供参考意见。

关键词：数字鸿沟农村老年人社会参与老龄化

基于RCM的混流式水轮发电机组导水机构维修决策

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水电站机电技术 2024年第5期47卷 19-21页

作者：何有良云南大唐观音岩水电开发有限公司云南昆明650000

新能源发电的大量并网,要求常规机组更频繁地参与电网调峰调频,因而要求常规发电企业进一步提升设备可靠性和机组运行稳定性。本文提出了改进的以可靠性为中心的维修决策方法,并应用于水电机组的导水机构。首先划分设备单元,确定检修单... 详细信息

新能源发电的大量并网,要求常规机组更频繁地参与电网调峰调频,因而要求常规发电企业进一步提升设备可靠性和机组运行稳定性。本文提出了改进的以可靠性为中心的维修决策方法,并应用于水电机组的导水机构。首先划分设备单元,确定检修单元,然后进行故障模式及影响分析并计算故障模式风险优先数RPN,最后利用RPN进行逻辑决断,确定维修策略。实例验证了维修决策方法的可行性与有效性,可推广应用于发电企业。

关键词：水轮机导水机构 RCM RPN 维修决策

Mission-driven autonomous perception and fusion based on UAV swarm

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Chinese Journal of Aeronautics 2020年第11期33卷 2831-2834页

作者： you he Research Institute of Information Fusion Naval Aviation UniversityYantai 264001China

Distributed autonomous situational awareness is one of the most important foundation for Unmanned Aerial Vehicle(UAV)swarm to implement various *** the application environment being usually characterized by strong confrontation,high dynamics,and deep uncertainty,the distributed situational awareness system based on UAV swarm needs to be driven by the mission requirements,while each node in the network can autonomously avoid collisions and perform detection mission through limited resource sharing as well as complementarity of respective *** efficiently solving the problems of self-avoidance,autonomous flocking and splitting,joint estimation and control,etc.,perception data from multi-platform multi-source should be extracted and fused reasonably,to generate refined,tailored target information and provide reliable support for decision-making.

关键词： Autonomous perception Consensus Distributed information fusion Situation awareness State estimation Swarm Unmanned aerial vehicle

鄂尔多斯盆地庆城油田页岩油开发技术探索与实践

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大庆石油地质与开发 2024年第4期43卷 170-180页

作者：屈雪峰何右安尤源薛婷李桢吴阿蒙中国石油长庆油田公司勘探开发研究院陕西西安710018 低渗透油气田勘探开发国家工程实验室陕西西安710018 中国石油大学(北京)地球科学学院北京102249

为解决鄂尔多斯盆地庆城油田页岩油规模开发中遇到的技术难题,将矿场实践和理论分析相结合开展技术方法探索及认识创新。针对甜点定量预测难题,创建甜点指数(I_(SI)),构建地质品质指数(G_(GQ)),形成多学科三维甜点定量优选技术;针对提... 详细信息

为解决鄂尔多斯盆地庆城油田页岩油规模开发中遇到的技术难题,将矿场实践和理论分析相结合开展技术方法探索及认识创新。针对甜点定量预测难题,创建甜点指数(I_(SI)),构建地质品质指数(G_(GQ)),形成多学科三维甜点定量优选技术;针对提高油层钻遇率难题,构建了“四个迭代”的水平井轨迹实时调整技术;针对多油层叠合储量动用难题,建立4种差异化布井模式,形成页岩油水平井一次动用立体布井技术;针对页岩油单井产量递减快,含水下降慢的问题,形成页岩油水平井差异化闷、排、采技术。通过应用以上技术,庆城油田实现年均增长产油量50×10^(4)t,2023年产油量超过200×10^(4)t。庆城油田实现规模效益开发,坚定了国内陆相页岩油规模效益开发的信心,研究成果可为国内外同类页岩油开发提供借鉴。

关键词：页岩油开发技术甜点评价油层钻遇率庆城油田鄂尔多斯盆地

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腹腔镜阑尾手术治疗急性阑尾炎患者的临床价值分析

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中国医疗器械信息 2024年第3期30卷 128-130页

作者：游和海福建省漳州市招商局经济技术开发区第一医院普外科福建漳州363100

目的:探讨腹腔镜阑尾手术治疗急性阑尾炎的临床疗效。方法:针对2020年2月~2023年2月本院收治的51例急性阑尾炎患者进行分组对照研究,采用随机数字表法分为观察组和对照组,26例观察组急性阑尾炎患者接受腹腔镜阑尾手术治疗,25例对照组急... 详细信息

目的:探讨腹腔镜阑尾手术治疗急性阑尾炎的临床疗效。方法:针对2020年2月~2023年2月本院收治的51例急性阑尾炎患者进行分组对照研究,采用随机数字表法分为观察组和对照组,26例观察组急性阑尾炎患者接受腹腔镜阑尾手术治疗,25例对照组急性阑尾炎患者接受开腹阑尾切除手术治疗,比较手术疗效及术后恢复情况。结果:对比首次排气时间,观察组更短(P<0.05)。对比下床活动时间,观察组更短(P<0.05)。对比住院时间,观察组更短(P<0.05)。对比疼痛VAS评分(术后24h、48h、72h),观察组更低(P<0.05)。对比术后炎性因子指标(C反应蛋白,白细胞介素-6,降钙素原),观察组低于对照组(P<0.05)。对比术后细胞免疫功能指标(白细胞计数,中性粒细胞数),观察组更低(P<0.05)。结论:腹腔镜阑尾手术的实施,可以有效治疗急性阑尾炎,降低手术治疗风险,能够让患者更快、更好地恢复健康。

关键词：腹腔镜阑尾手术急性阑尾炎临床疗效

基于TGF-β/Smads信号通路探讨苦参碱对糖尿病肾病小鼠的影响

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中国临床药理学杂志 2024年第13期40卷 1923-1927页

作者：孔静何友立杨明明刘颖菏泽医学专科学校附属医院手术室山东菏泽274000 菏泽医学专科学校临床医学系山东菏泽274000 菏泽市立医院内分泌代谢病科山东菏泽274000 菏泽市立医院药学部山东菏泽274000

目的研究苦参碱通过调控转化生长因子-β/信号传导蛋白(TGF-β/Smads)信号通路改善糖尿病肾病(DN)的作用及机制。方法将C57BL/6小鼠随机分为NC组、DN组、DN+苦参碱组和DN+二甲双胍组,每组10只。除NC组外,其余各组均用高脂高糖饮食加腹... 详细信息

目的研究苦参碱通过调控转化生长因子-β/信号传导蛋白(TGF-β/Smads)信号通路改善糖尿病肾病(DN)的作用及机制。方法将C57BL/6小鼠随机分为NC组、DN组、DN+苦参碱组和DN+二甲双胍组,每组10只。除NC组外,其余各组均用高脂高糖饮食加腹腔注射链脲佐菌素(STZ)的方法建立小鼠DN模型,造模成功后DN+苦参碱组灌胃给予苦参碱治疗4周,DN+二甲双胍组给予二甲双胍,DN组和NC组给予等量0.9%NaCl。用蛋白质印迹(Western blot)法检测小鼠肾组织中Ⅳ型胶原蛋白(ColⅣ)、纤连蛋白(FN)、Smad同源物2/3(Smad2/3)和磷酸化Smad2/3(p-Smad2/3)的表达水平;用生化法检测小鼠血糖、血肌酸酐和尿素氮水平。结果NC组、DN组和DN+苦参碱组小鼠血糖水平分别为(8.16±2.53)、(24.84±4.67)和(23.88±3.57)mmol·L^(-1);血肌酸酐水平分别为(36.48±5.63)、(97.51±10.59)和(41.88±7.26)mmol·L^(-1);尿素氮水平分别为(53.11±4.72)、(91.50±8.62)和(63.29±5.69)mmol·L^(-1);肾组织中ColⅣ蛋白的表达水平分别为1.00±0.19、3.34±0.58和1.99±0.44,FN蛋白的表达水平分别为1.00±0.21、3.63±0.47和1.79±0.43,p-Smad2/3/Smad2/3分别为1.00±0.18、2.74±0.51和1.08±0.33。上述指标,NC组与DN组相比,在统计学上差异均有统计学意义(均P<0.05)。结论苦参碱能够有效抑制TGF-β/Smads信号通路的激活,减少细胞外基质相关蛋白的聚积,从而发挥保护DN肾损伤的作用。

关键词：苦参碱糖尿病肾病转化生长因子-β/信号传导蛋白信号通路纤连蛋白 Ⅳ型胶原蛋白