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Numerical analysis of hydraulic fracture propagation in deep shale reservoir with different injection strategies

Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3558-3574页

作者： yingjie xia Mingyu Yao Tianjiao Li Hai Yang Chun'an Tang School of Civil Engineering Dalian University of TechnologyDalian116024China Deep Underground Engineering Research Center Dalian University of TechnologyDalian116024China CNPC Chuanqing Drilling Engineering Company Limited Chengdu610051China

Deep shale reservoirs are characterized by elevated breakdown pressures,diminished fracture complexity,and reduced modified volumes compared to medium and shallow ***,it is urgent to investigate particular injection strategies that can optimize breakdown pressure and fracturing efficiency to address the increasing demands for deep shale reservoir *** this study,the efficiency of various stimulation strategies,including multi-cluster simultaneous fracturing,modified alternating fracturing,alternating shut-in fracturing,and cyclic alternating fracturing,was ***,the sensitivity of factors such as the cycle index,shut-in time,cluster spacing,and horizontal permeability was ***,the flow distribution effect within the wellbore was *** results indicate that relative to multi-cluster simultaneous fracturing,modified alternating fracturing exhibits reduced susceptibility to the stress shadow effect,which results in earlier breakdown,extended hydraulic fracture lengths,and more consistent propagation despite an increase in breakdown *** alternating shut-in fracturing benefits the increase of fracture length,which is closely related to the shut-in ***,cyclic alternating fracturing markedly lowers breakdown pressure and contributes to uniform fracture propagation,in which the cycle count plays an important *** alternating fracturing demonstrates insensitivity to variations in cluster spacing,whereas horizontal permeability is a critical factor affecting fracture *** wellbore effect restrains the accumulation of pressure and flow near the perforation,delaying the initiation of hydraulic *** simulation results can provide valuable numerical insights for optimizing injection strategies for deep shale hydraulic fracturing.

关键词： Fracture propagation Numerical simulation Hydraulic fracturing Rock failure process analysis(RFPA) Injection strategy

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空地协同场景下具有隐私保护的高效异构认证方案

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浙江大学学报（工学版） 2024年第10期58卷 1981-1991页

作者：刘雪娇赵祥夏莹杰曹天聪杭州师范大学信息科学与技术学院浙江杭州311121 杭州电子科技大学微电子研究院浙江杭州310018 浙江大学计算机科学与技术学院浙江杭州310027

在空地协同场景下车辆与无人机频繁通信存在异构认证效率低、隐私容易泄露、计算开销较大等问题,为此提出高效的异构认证方案.设计基于Schnorr签名和物理不可克隆函数的高效异构认证协议以抵抗克隆攻击、物理攻击和重放攻击等安全威胁;... 详细信息

在空地协同场景下车辆与无人机频繁通信存在异构认证效率低、隐私容易泄露、计算开销较大等问题,为此提出高效的异构认证方案.设计基于Schnorr签名和物理不可克隆函数的高效异构认证协议以抵抗克隆攻击、物理攻击和重放攻击等安全威胁;设计基于模糊提取器和身份令牌的车辆假名生成方法,在保护用户隐私的同时准确追溯恶意车辆的身份信息,实现有条件的隐私保护;设计基于密钥共享的切换认证协议,减少认证过程中的计算量,降低认证过程中无人机的能量消耗.实验结果表明,所提方案有效提高了车辆与无人机认证效率,与现有方案相比,平均降低了54.8%的计算开销.

关键词：空地协同异构相互认证密钥协商切换认证隐私保护

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页岩数字岩心重构与水力压裂数值试验

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工程科学学报 2024年第3期46卷 556-566页

作者：姚明宇李天娇丛文雨师耀利夏英杰唐春安大连理工大学建设工程学院大连116024 中国石油新疆油田公司勘探开发研究院克拉玛依834000

为了实现对深部页岩油储层水力裂缝扩展规律的精细研究,以吉木萨尔凹陷芦草沟组陆相页岩油储层下甜点主要油层段为研究对象,对3684.62~3705.70 m深度范围内的20组页岩样品进行扫描并构建数字岩心,开展水力压裂数值试验.试验获得了各模... 详细信息

为了实现对深部页岩油储层水力裂缝扩展规律的精细研究,以吉木萨尔凹陷芦草沟组陆相页岩油储层下甜点主要油层段为研究对象,对3684.62~3705.70 m深度范围内的20组页岩样品进行扫描并构建数字岩心,开展水力压裂数值试验.试验获得了各模型的破裂压力和水力裂缝扩展路径.结果表明:破裂压力随孔隙度的增加而降低,随着脆性矿物体积分数的增加而增加,和石英体积分数呈现较明显的线性关系.水力裂缝在孔隙位置起裂,连通独立的孔隙区域并沿着贯通的孔隙区域继续扩展.在远离孔隙区域时,水力裂缝主要沿垂直于最小主应力方向延伸.水力裂缝的复杂程度均随石英体积分数和孔隙度的增加而增加,但也会受到矿物分布形态的影响.当石英体积分数或孔隙度较高且呈现大面积连通分布时,水力裂缝的扩展受到抑制,水力压裂的增渗改造效果较弱.

关键词：微观矿物组分数字岩心水力压裂页岩油储层真实破裂过程分析

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农村家庭数字反哺的特征、抗阻因素与解决路径研究——基于江西新干县NY村家庭代际互动实践

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浙江理工大学学报（社会科学版） 2024年第3期52卷 314-321页

作者：董书华夏莹洁浙江理工大学史量才新闻与传播学院杭州310018

从“数字反哺”的相关理论出发,以江西省新干县NY村8户家庭为研究对象,运用深度访谈和参与式观察等研究方法,描述了农村家庭代际互动场域中子代对亲代数字反哺的现状。研究发现,农村家庭数字反哺存在以下特征:反哺节点明显,浅层次与反... 详细信息

从“数字反哺”的相关理论出发,以江西省新干县NY村8户家庭为研究对象,运用深度访谈和参与式观察等研究方法,描述了农村家庭代际互动场域中子代对亲代数字反哺的现状。研究发现,农村家庭数字反哺存在以下特征:反哺节点明显,浅层次与反复性并存;同村晚辈帮扶,邻里互哺助力;子代反哺主动性不足。农村老年群体的社会边缘地位、技术恐慌心理、代际沟通失衡均构成了数字反哺的抗阻因素。基于实地调研,认为跨越农村老年群体的数字鸿沟需要社会各方共同努力:一方面,在家庭场域中实施数字反哺,发挥子女的扶持与协助作用,帮助农村老年群体适应数字化社会;另一方面,须构建政府、新闻传媒、大众等多元主体共建共享的社会治理体系,保障农村老年人的数字权利,帮助老年人共享数字时代的发展成果,让数字化、智能化成果真正惠及全社会。

关键词：数字反哺数字鸿沟农村家庭老年人代际互动

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成人学习理论干预模式在四肢骨折术后患者中的应用效果

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临床医药实践 2024年第2期33卷 137-140页

作者：夏瑛洁江蕊黄婷敏江南大学附属医院江苏无锡214000

目的:探讨成人学习理论的干预模式在四肢骨折术后患者中的应用效果。方法:选择2020年3月—2021年3月收治的四肢骨折术后患者144例,随机分为对照组和观察组,每组72例。对照组采用常规干预模式,观察组采用基于成人学习理论的干预模式。比... 详细信息

目的:探讨成人学习理论的干预模式在四肢骨折术后患者中的应用效果。方法:选择2020年3月—2021年3月收治的四肢骨折术后患者144例,随机分为对照组和观察组,每组72例。对照组采用常规干预模式,观察组采用基于成人学习理论的干预模式。比较两组自我效能感、肿胀与疼痛程度、术后并发症发生率以及生活质量。结果:观察组干预后自我效能感评分和生活质量评分高于对照组,肢体周径差、疼痛程度评分及术后并发症发生率低于对照组,差异有统计学意义(P<0.05)。结论:将基于成人学习理论的干预应用于四肢骨折术后患者中,可逐渐增强自我效能感,缓解肢体肿胀、疼痛,有效减少术后相关并发症的发生,改善患者生活质量模式。

关键词：成立学习理论四肢骨折肿胀疼痛生活质量

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基于改进YOLOv5算法和DeepSort算法的多目标检测和跟踪

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济南大学学报（自然科学版） 2024年第5期38卷 556-563页

作者：李志安林道程姜晓凤夏英杰李金屏济南大学信息科学与工程学院山东济南250022 济南大学山东省网络环境智能计算技术重点实验室山东济南250022 济南大学信息处理与认知计算山东省高校重点实验室山东济南250022

针对因受水面波纹、反光及目标外观特征相似而导致的游泳池中目标检测跟踪困难的问题,提出一种基于改进YOLOv5算法和DeepSort算法的多目标检测和跟踪方法;通过引入注意力机制改进YOLOv5算法,增强算法对目标特征的提取能力;将检测结果输... 详细信息

针对因受水面波纹、反光及目标外观特征相似而导致的游泳池中目标检测跟踪困难的问题,提出一种基于改进YOLOv5算法和DeepSort算法的多目标检测和跟踪方法;通过引入注意力机制改进YOLOv5算法,增强算法对目标特征的提取能力;将检测结果输入到DeepSort算法中,在级联匹配中引入K邻域限制筛选目标检测框,减少因目标外观特征不明显引起的身份切换问题;利用匈牙利算法对检测框和预测框进行匹配,对未匹配成功的检测框采用距离交并比代替交并比进行二次匹配,提高DeepSort算法的跟踪性能;通过对比实验和消融实验验证所提出的多目标检测跟踪算法的性能。结果表明:改进的YOLOv5算法平均精准度提高2%,结合DeepSort算法跟踪检测,身份切换平均减少58次,多目标跟踪精确率为80.26%,比原始YOLOv5算法和Deepsort算法跟踪准确率提升了3.85%。

关键词：目标检测目标跟踪 YOLOv5算法 DeepSort算法注意力机制 K邻域限制

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Influence of pore pressure on tensile fracture growth in rocks： a new explanation based on numerical testing

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Frontiers of Earth Science 2015年第3期9卷 412-426页

作者： Shou MA Jianchun GUO Lianchong LI Leslie George THAM yingjie xia Chun'an TANG State Key Laboratory of Oil and Gas Geology and Exploitation Southwest Petroleum University Chengdu 610500 China SINOPEC Shengli Oilfield Company Dongying 257000 China School of Civil Engineering Dalian University of Technology Dalian 116024 China Department of Civil Engineering The University of Hong Kong Hong Kong China

The diffusion of pore fluid pressures may create both spatial and temporal effective stress gradients that influence or control the development and evolution of fractures within rock masses. To better understand the controls on fracturing behavior, numerical simulations are performed using a progressive fracture modeling approach that shares many of the same natural kinematic features in rocks, such as fracture growth, nucleation, and termination. First, the pinch-off breaking test is numerically performed to investigate the tensile failure of a rock specimen in a uniform pore pressure field. In this numerical simulation, both mechanical and hydrological properties of a suite of rocks are measured under simulated laboratory conditions. The complete tensional failure process of the rock specimen under pore pressure was reproduced. Second, a double-notched specimen is numerically extended to investigate how the water flow direction or pore pressure gradient influences the fracture growth. An exhaustive sensitivity study is conducted that examines the effects of varying both hydrological and mechanical boundary conditions. The simulation results indicate that local fluid pressure gradients strongly influence the state of stress in the solids and, thereby, fracture growth. Fracture and strength behavior is influenced not only by the pore pressure magnitude on a local scale around the fracture tip, but also by the orientation and distribution of pore pressure gradients on a global scale. Increasing the fracture growth rate increases the local model permeability and decreases the sample strength. The results of this study may provide useful information concerning the degree of hydrological and mechanical coupling action under geologic conditions.

关键词： pore pressure effective stress heterogeneous numerical simulation fracture growth rock

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Theoretical study on the lasing plasmon of a split ring for label-free detection of single molecules and single nanoparticles

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Chinese Physics B 2018年第5期27卷 504-512页

作者： Chunjie Zheng Tianqing Jia Hua Zhao yingjie xia Shian Zhang Zhenrong Sun State Key Laboratory of Precision Spectroscopy College of Physics and Materials East China Normal University Shanghai 200062 China

This paper reports the plasmonic lasing of a split ring filled with gain material in water. The lasing mode（1500 nm）is far from the pump mode（980 nm）, which can depress the detection noise from the pump light. The laser intensities of the two modes simultaneously increase by more than 10^3 in amplitude, which can intensify the absorption efficiency of the pumping light and enhance the plasmonic lasing. The plasmonic lasing is a sensitive sensor. When a single protein nanoparticle（n = 1.5, r = 1.25 nm） is trapped in the gap of the split ring, the lasing spectrum moves by 0.031 nm, which is much larger than the detection limit of 10^-5 nm. Moreover, the lasing intensity is also very sensitive to the trapped nanoparticle. It reduces to less than 1/600 when a protein nanoparticle（n = 1.5, r = 1.25 nm） is trapped in the gap.

关键词： label-free detection split-ring resonators plasmonic lasing single molecules and single nanoparticles

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2,3,7,8-Tetrachlorodibenzo-p-dioxin promotes migration ability of primary cultured rat astrocytes via aryl hydrocarbon receptor

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Journal of Environmental Sciences 2019年第2期31卷 368-376页

作者： Yangsheng Chen Rui Sha Li Xu yingjie xia Yiyun Liu Xuejun Li Heidi Qunhui Xie Naijun Tang Bin Zhao State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences Department of Occupational and Environmental Health sTianjin Medical University

Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed woundhealing assay and Transwell? motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations(10^(-10) and/or 10^(-9) mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mR NA expression of two promigratory genes, including cell division cycle 42(CDC42) and matrix metalloproteinase 2(MMP2)was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor(AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.

关键词： 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Astrocyte Migration Gene expression Aryl hydrocarbon receptor (AhR) pathway

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Dioxin induces expression of hsa-mi R-146b-5p in human neuroblastoma cells

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Journal of Environmental Sciences 2018年第1期30卷 260-267页

作者： Tuan Xu Heidi Q.Xie Yunping Li yingjie xia Rui Sha Lingyun Wang Yangsheng Chen Li Xu Bin Zhao State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Dioxin can cause a series of neural toxicological effects. Micro RNAs（mi Rs） play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa-mi R-146 b-5 p appears to be involved in neurodegenerative diseases and brain tumors. However, little is known about effects of dioxin on the expression of hsa-mi R-146 b-5 p. We found that the hsa-mi R-146 b-5 p expression and its promoter activity were significantly increased in dioxin treated SK-N-SH cells, a human-derived neuroblastoma cell line. Potential roles of hsa-mi R-146 b-5 p in mediating neural toxicological effects of dioxin may be due to the regulation of certain target genes. We further confirmed that hsa-mi R-146 b-5 p significantly suppressed acetylcholinesterase（ACh E） activity and targeted the3′-untranslated region of the ACh E T subunit, which has been down-regulated in dioxin treated SK-N-SH cells. Functional bioinformatic analysis showed that the known and predicted target genes of hsa-mi R-146 b-5 p were involved in some brain functions or cyto-toxicities related to known dioxin effects, including synapse transmission, in which ACh E may serve as a responsive gene for mediating the effect.

关键词： 2 3 7 8-Tetrachlorodibenzo-p-dioxin(TCDD) MicroRNA Acetylcholinesterase(AChE) Neuron Transcription regulation Post-transcriptional regulation

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