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Securing offshore resources development: A mathematical investigation into gas leakage in long-distance flexible pipes

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Petroleum Science 2024年第4期21卷 2734-2744页

作者： Xiang-An Lu Liang-Liang Jiang Jian-Sheng Zhang Min-gui wang Guangling College of Yangzhou University Department of Chemical and Petroleum Engineering University of Calgary Department of Energy and Power Engineering Tsinghua University

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development. Under high pressure conditions, small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space, incurring annular pressure build-up and/or production of acidic environment, which poses serious challenges to the structure and integrity of the flexible pipes. Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature, annular structure, external temperature. In a long-distance gas flexible pipe, moreover, gas permeation exhibits non-uniform features, and the gas permeated into the annular space flows along the metal gap. To assess the complex gas transport behavior in long-distance gas flexible pipes, a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes, the diffusion of gas in the inner liner, and the gas seepage in the annular space under varying permeable properties of the annulus. In addition, the effect of a variable temperature is accounted. A numerical calculation method is accordingly constructed to solve the coupling mathematical equations. The annular permeability was shown to significantly influence the distribution of annular pressure. As permeability increases, the annular pressure tends to become more uniform, and the annular pressure at the wellhead rises more rapidly. After annular pressure relief followed by shut-in, the pressure increase follows a convex function. By simulating the pressure recovery pattern after pressure relief and comparing it with test results, we deduce that the annular permeability lies between 123 and 512 m D. The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources.

关键词： Offshore resources development Transport security Long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation

Lymphatic plastic bronchitis and primary chylothorax: A study based on computed tomography lymphangiography

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World Journal of Clinical Cases 2024年第14期12卷 2350-2358页

作者： Xing-Peng Li Yan Zhang Xiao-Li Sun Kun Hao Meng-Ke Liu Qi Hao Ren-gui wang Department of Radiology Beijing Shijitan Hospital Affiliated to Capital Medical UniversityBeijing 100038China Department of Radiology Qilu HospitalShandong UniversityJinan 250063Shandong ProvinceChina Department of Lymph Surgery Beijing Shijitan Hospital Affiliated to Capital Medical UniversityBeijing 100038China Department of Radiology People's Hospital of Peking UniversityThe Second School of Clinical Medicine of Peking UniversityBeijing 100034China

BACKGROUND This study presents an evaluation of the computed tomography lymphangio-graphy(CTL)features of lymphatic plastic bronchitis(PB)and primary chylotho-rax to improve the diagnostic accuracy for these two *** To improve the diagnosis of lymphatic PB or primary chylothorax,a retrospective analysis of the clinical features and CTL characteristics of 71 patients diagnosed with lymphatic PB or primary chylothorax was *** The clinical and CTL data of 71 patients(20 with lymphatic PB,41 with primary chylothorax,and 10 with lymphatic PB with primary chylothorax)were collected *** was performed in all *** clinical manifestations,CTL findings,and conventional chest CT findings of the three groups of patients were *** chi-square test or Fisher's exact test was used to compare the differences among the three groups.A difference was considered to be statistically significant when P<***(1)The percentages of abnormal contrast medium deposits on CTL in the three groups were as follows:Thoracic duct outlet in 14(70.0%),33(80.5%)and 8(80.0%)patients;peritracheal region in 18(90.0%),15(36.6%)and 8(80.0%)patients;pleura in 6(30.0%),33(80.5%)and 9(90.0%)patients;pericardium in 6(30.0%),6(14.6%)and 4(40.0%)patients;and hilum in 16(80.0%),11(26.8%)and 7(70.0%)patients;and(2)the abnormalities on conven-tional chest CT in the three groups were as follows:Ground-glass opacity in 19(95.0%),18(43.9%)and 8(80.0%)patients;atelectasis in 4(20.0%),26(63.4%)and 7(70.0%)patients;interlobular septal thickening in 12(60.0%),11(26.8%)and 3(30.0%)patients;bronchovascular bundle thickening in 14(70.0%),6(14.6%)and 4(40.0%)patients;localized mediastinal changes in 14(70.0%),14(34.1%),and 7(70.0%)patients;diffuse mediastinal changes in 6(30.0%),5(12.2%),and 3(30.0%)patients;cystic lesions in the axilla in 2(10.0%),6(14.6%),and 2(20.0%)patients;and cystic lesions in the chest wall in 0(0%),2(4.9%),and 2(4.9%)*** CTL is

关键词： Lymphatic Plastic bronchitis Primary chylothorax Direct lymphangiography Computed tomography lymphangiography

Tuberous sclerosis complex combined with primary lymphedema:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2642-2648页

作者： Xing-Peng Li Xiao-Li Sun Xin Liu Zhe Wen Li-Hua Jiang Yan Fu Yun-Long Yue Ren-gui wang Department of Radiology Beijing Shijitan Hospital Affiliated to Capital Medical UniversityBeijing 100038China Department of Lymph Surgery Beijing Shijitan Hospital Affiliated to Capital Medical UniversityBeijing 100038China Department of Nuclear Medicine Beijing Shijitan Hospital Affiliated to Capital Medical UniversityBeijing 100038China Department of MRI Beijing Shijitan Hospital Affiliated to Capital Medical UniversityBeijing 100038China

BACKGROUND Tuberous sclerosis complex(TSC)and primary lymphedema(PLE)are both rare diseases,and it is even rarer for both to occur in the same *** this work,we have provided a detailed description of a patient's clinical presentation,imaging findings,and *** a retrospective analysis was conducted on 14 published relevant case *** SUMMARY A 16-year-old male came to our hospital for treatment due to right lower limb *** swelling is already present from *** patient’s memory had been progressively *** had occurred 1 year prior at an unknown *** patient was diagnosed with TSC combined with PLE through multimodal imaging examination:Computed tomography,magnetic resonance imaging,and *** patient underwent *** swelling of the patient's right lower limb significantly improved after *** did not *** taking antiepileptic drugs and *** TSC with PLE is a rare and systemic *** can detect lesions of this disease,which are important for diagnosis and treatment.

关键词： Tuberous sclerosis complex Lymphedema Sirolimus Multimodal imaging examination Case report

生态资源价值化助推乡村振兴的逻辑机理与突破路径

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自然资源学报 2024年第1期39卷 29-48页

作者：郎宇王桂霞吉林农业大学经济管理学院长春130118

遵循“山水林田湖草沙”系统整全开发理念盘活乡村生态资源价值,是新时代助推乡村全面振兴的关键。在揭示生态资源价值化所经历的“生态资源价值培育—生态资源资本深化—生态资源价值实现”三阶段发展内涵的基础上,阐述生态资源价值化... 详细信息

遵循“山水林田湖草沙”系统整全开发理念盘活乡村生态资源价值,是新时代助推乡村全面振兴的关键。在揭示生态资源价值化所经历的“生态资源价值培育—生态资源资本深化—生态资源价值实现”三阶段发展内涵的基础上,阐述生态资源价值化与乡村振兴的内涵逻辑关联,并深入剖析生态资源价值化助推乡村振兴的三阶段逻辑机理,探讨助推乡村振兴的区域典型模式以及在助推过程中需要克服的区域现实难点和共性现实难点。基于逻辑发展、区域难点、共性难点三个视角提出生态资源价值化助推乡村振兴的突破路径,为盘活生态资源价值,助推乡村全面振兴提供科学依据和理论指导。

关键词：生态资源价值化山水林田湖草沙综合系统开发乡村振兴

多模式下的车辆和无人机联合配送模型与优化算法

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控制与决策 2024年第7期39卷 2125-2132页

作者：贾兆红王少贵刘闯安徽大学互联网学院合肥230000 安徽大学计算机科学与技术学院合肥230000

无人机已广泛用于物流配送,具有快速投递和低成本的优势.针对远离仓库中心、交通受限制客户的需求,在车机并行配送模式上引入车载无人机以服务该类客户,提出多模式下的车辆和无人机联合配送模型及其路径优化问题.该模型融合了车机协同... 详细信息

无人机已广泛用于物流配送,具有快速投递和低成本的优势.针对远离仓库中心、交通受限制客户的需求,在车机并行配送模式上引入车载无人机以服务该类客户,提出多模式下的车辆和无人机联合配送模型及其路径优化问题.该模型融合了车机协同配送模型和并行配送模型,包括搭载无人机的卡车和独立的无人机舰队.在此基础上建立以最小化交付时间为优化目标的混合整数规划模型,并设计基于知识学习策略的多算子遗传算法来提高搜索效率.实验结果表明,与传统交付方式相比,车辆与无人机联合配送模型可显著减少交付时间.在大规模数据集上,改进的遗传算法表现出更好的性能.该研究成果可为解决物流配送中的复杂动态的“最后一公里”问题提供指导和参考.

关键词：卡车无人机联合配送路径优化无人机遗传算法最后一公里

农户分化、价值认知与农户融入市场化生态补偿——以化肥减量施用为例

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山西财经大学学报 2024年第2期46卷 68-83页

作者：郎宇王桂霞吉林农业大学经济管理学院吉林长春130118

基于吉林省316户水稻种植户的实地调研样本,以化肥减量施用为例,运用SEM方法实证检验农户分化、价值认知对农户融入市场化生态补偿的影响,并分析不同群组间的差异性。研究发现,农户分化不仅是激发农户融入市场化生态补偿的直接动因,而... 详细信息

基于吉林省316户水稻种植户的实地调研样本,以化肥减量施用为例,运用SEM方法实证检验农户分化、价值认知对农户融入市场化生态补偿的影响,并分析不同群组间的差异性。研究发现,农户分化不仅是激发农户融入市场化生态补偿的直接动因,而且通过影响价值认知间接发挥作用。进一步的多群组分析发现,较之浅分化农户,深分化农户群组中推动农户融入市场化生态补偿的路径更多且影响更加强烈。

关键词：农户分化价值认知化肥减量市场化生态补偿生态产品价值实现

产学研融合的快速热循环注塑虚拟仿真实验教学课程建设与实践

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高分子通报 2024年第8期37卷 1117-1122页

作者：董桂伟王桂龙赵国群山东大学材料科学与工程学院济南250061

面向“虚拟仿真实验教学2.0”要求和高阶性、创新性、挑战度的“两性一度”的“金课”建设标准,将科研、教育、生产三者在功能和资源上的优势进行集成,构建了产学研融合的快速热循环注塑虚拟仿真实验教学课程。针对虚拟仿真实验项目的... 详细信息

面向“虚拟仿真实验教学2.0”要求和高阶性、创新性、挑战度的“两性一度”的“金课”建设标准,将科研、教育、生产三者在功能和资源上的优势进行集成,构建了产学研融合的快速热循环注塑虚拟仿真实验教学课程。针对虚拟仿真实验项目的现代信息技术性强、教学时空拓展性好等特点,开展了基于雨课堂、BOPPPS教学模型(一种学生全方位参与和及时反馈交流的教学模式和监测系统,包括导言(Bridge-in)、目标(Objective)、前测(Pre-assessment)、参与式学习(Participatory Learning)、后测(Postassessment)与总结(Summary)六个环节等)等以学生为中心的互动在线实验教学实践和产学研协同多元考核机制探索,服务创新人才培养,取得良好教学效果。

关键词：产学研融合快速热循环注塑虚拟仿真实验教学

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构式化视角下英语临界复杂介词的固化研究

现代外语 2024年第3期47卷 316-330页

作者：吴侠邵斌王贵浙江大学浙江省杭州市310058

英语复杂介词应界定为词还是短语,学界未有定论。本文以构式化理论为视角,借助语义向量空间的定量方法,考察临界复杂介词in the face of的固化过程。本研究发现:1)在过去200年间,该构式的能产性和图式性增加,而组构性降低。从基于使用... 详细信息

英语复杂介词应界定为词还是短语,学界未有定论。本文以构式化理论为视角,借助语义向量空间的定量方法,考察临界复杂介词in the face of的固化过程。本研究发现:1)在过去200年间,该构式的能产性和图式性增加,而组构性降低。从基于使用的视角来看,这种变化趋势不仅反映了构式固化程度的增强,同时也表明其逐渐向介词范畴的演进;2)该构式的固化过程并不是单向的线性发展,而是表现为构式节点间横向和纵向关系的变化;3)该构式固化的动因有二:一是高能产性导致的组块效应,二是识解层面的语义简化。

关键词：临界复杂介词构式化固化语义向量空间

定制服务代理对消费者购买意愿的影响--基于AI聊天机器人与人工服务比较的实验研究

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学习与探索 2024年第6期 145-159,196页

作者：王永贵张静浙江工商大学现代商贸研究中心浙江工商大学数字创新与管理研究院浙江工商大学工商管理学院首都经济贸易大学

人工智能(AI)的飞速发展在进一步拓展企业定制服务应用场景的同时,其带来的个性化和隐私问题也愈发受到重视。本研究基于隐私计算理论对定制服务中的“风险—收益”困境进行了研究:通过多个在线医护场景的定制服务实验,对定制服务代理... 详细信息

人工智能(AI)的飞速发展在进一步拓展企业定制服务应用场景的同时,其带来的个性化和隐私问题也愈发受到重视。本研究基于隐私计算理论对定制服务中的“风险—收益”困境进行了研究:通过多个在线医护场景的定制服务实验,对定制服务代理与购买意愿之间的关系进行了剖析,对能力感知与隐私担忧在定制服务代理与消费者购买意愿之间的链式中介作用进行了检验,并对定制服务平台的隐私保护声明在定制服务代理与消费者购买意愿之间关系的调节作用进行了验证。实验结果发现:(1)AI聊天机器人作为定制服务代理对购买意愿的促进作用明显弱于人工服务代理;(2)能力感知和隐私担忧在定制服务代理与购买意愿之间扮演着链式中介角色。其中,消费者对AI聊天机器人的能力感知弱于人工;对AI聊天机器人的隐私担忧高于人工,能力感知负向影响隐私担忧;(3)定制服务平台的隐私保护声明能够调节定制服务代理与购买意愿之间的关系,具有隐私保护声明的平台更能促进消费者的购买意愿。

关键词：定制服务代理 AI聊天机器人能力感知隐私担忧隐私计算消费者购买意愿

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