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大学新生爱情概念建构的认知隐喻解析

外语学刊 2024年第5期 42-47页

作者：徐知媛王凡菊浙江大学杭州310058

本文以认知隐喻理论为研究框架,探讨了中国大一新生对爱情概念的隐喻性建构。来自国内某高校73名大一新生完成关于“爱情是什么”的问卷回答。研究结果表明,处在人生重要过渡时期的大一新生,除使用食物、情绪体验和风景等常见的始源域外... 详细信息

本文以认知隐喻理论为研究框架,探讨了中国大一新生对爱情概念的隐喻性建构。来自国内某高校73名大一新生完成关于“爱情是什么”的问卷回答。研究结果表明,处在人生重要过渡时期的大一新生,除使用食物、情绪体验和风景等常见的始源域外,还使用相关研究尚未发现过的始源域,例如,知识、文娱活动等独具年龄特色的词汇建构爱情概念;而且所使用的始源域绝大部分是积极词汇,表明,大一新生对爱情总体上持肯定态度。性别影响爱情隐喻建构:在食物、风景、建筑、文娱活动等始源域选择上,两组未见显著差异;而在知识、物体、植物等始源域方面,两组存在显著差异;在具体的始源域词汇选择方面,女生比男生更多使用积极词汇,说明大一女生对于爱情持有更加乐观积极的态度。本研究结果表明,处在人生特殊阶段的中国大一学生,对爱情概念具有特殊的隐喻性建构,这种特殊的建构来源于其从高中阶段向大学阶段过渡时期对爱情的独特体验。本研究结果对大学教育工作者开展大学新生心理辅导及价值观念引领具有一定的参考意义。

关键词：大学新生认知隐喻爱情概念具身体验积极词汇性别

In vitro evaluation of artificial joints: a comprehensive review

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Advances in Manufacturing 2019年第1期7卷 1-14页

作者： Gang Shen ju-fan Zhang Feng-Zhou fang Centre of Micro/Nano Manufacturing Technology (MNMTDublin) University College Dublin Dublin Ireland State Key Laboratory of Precision Measuring Technology and Instruments Centre of Micro/Nano Manufacturing Technology (MNMT) Tianjin University Tianjin 300072 People's Republic of China

Development of artificial joints is a great progress for joint replacement operations of human being, but the short longevity of prostheses has concerned both industries and researchers since the advent of modem implants. Thus, continuous improvements have been made alongside the clinical applications. The methodologies to inspect the potential properties of new designs have also seen many advances. The test machines have evolved from easy pin-on-disk configuration to the modem joint simulator. Besides, various wear traces provided by testing machines are investigated greatly, and multi-directional files are recommended as motion profiles for in vitro testing. The typical testing parameters, like sliding speed or loading profile, are discussed in this article, and their working mechanisms are described in detail. Meanwhile, the calf or bovine serum has been regarded as the gold standard for testing lubricant, and the future trend of fluid will be focused on investigating the effects of lubricant composites on the tribological properties. Hard particles and proteins are discussed as well, and their effects on the wear mechanisms are the focus. Finally, various approaches to measure the wear rate, wear factor and the thickness of lubricant film are presented, and suggestions are given for the development in future.

关键词： Artificial joint Methodology Testing parameter Wear rate

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跨域数据管理

计算机科学 2024年第1期51卷 4-12页

作者：杜小勇李彤卢卫范举张峰柴云鹏数据工程与知识工程教育部重点实验室(中国人民大学) 北京100872 中国人民大学信息学院北京100872

随着数据成为新的生产要素和数字中国顶层战略的推进,跨域数据共享和流通对于实现数据要素价值最大化变得至关重要。国家通过布局全国一体化大数据中心体系、启动“东数西算”工程等一系列举措,为数据要素的跨域应用提供了基础设施。然... 详细信息

随着数据成为新的生产要素和数字中国顶层战略的推进,跨域数据共享和流通对于实现数据要素价值最大化变得至关重要。国家通过布局全国一体化大数据中心体系、启动“东数西算”工程等一系列举措,为数据要素的跨域应用提供了基础设施。然而,传统的数据管理局限于单一域内,无法满足跨域场景下的数据管理需求。跨域数据管理面临通信层面的跨空间域挑战、数据建模层面的异构模型融合问题,以及数据访问层面的跨信任域挑战。从跨空间域、跨管辖域和跨信任域3个视角出发,探讨了跨域数据管理的内涵、研究挑战及关键技术,并展望了其未来发展趋势。

关键词：数据管理跨空间域跨管辖域跨信任域

An investigation on HOBEM in evaluating ship wave of high speed displacement ship

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Journal of Hydrodynamics 2019年第3期31卷 531-541页

作者： Xi Chen Ren-chuan Zhu Ya-lan Song ju fan Marine Design & Research Institute of China Shanghai 200011 China State Key L aboratory of Ocean Engineering Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

A practical numerical tool is developed to evaluate ship waves of high speed displacement ships on the basis of potential flow theory, in which high order boundary element method (HOBEM) based on biquadratic shape functions is applied to solve the boundary value problem. Since the sinkage and trim of ship at high speeds are notable, influences of ship attitude on wave drag are investigated and three kinds of models are used to evaluate them. To make the numerical approach highly efficient, an incomplete LU factorization preconditioner is adopted and incorporated with the restarted generalized minimal residual method GMRES (m) to solve the boundary integral equation. A corresponding Fortran code is developed and applied to evaluate ship waves of the Wigley hull and 4a model, a transom stem ship. Computations are performed for both monohulls and catamarans over a wide range of Froude numbers (Fr= 0.10-l.00). Numerical issues including mesh convergence and computational efficiency are investigated at first. Computed results of the wave drag, sinkage and trim show generally good agreement with experimental data. Reasonable wave patterns are obtained and physical phenomena that wake angle max, where the largest waves occur, would become narrow at high speeds is also captured by the present computations. Numerical results indicate the proposed method would be accurate and efficient to evaluate resistance for hull design of high speed displacement ship.

关键词： High speed ship ship waves HOBEM ILU-GMRES sinkage and trim

SIMULATION OF TANK SLOSHING BASED ON OPENFOAM AND COUPLING WITH SHIP MOTIONS IN TIME DOMAIN

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Journal of Hydrodynamics 2012年第3期24卷 450-457页

作者： LI Yu-long ZHU Ren-chuan MIAO Guo-ping fan ju State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University Shanghai 200240 China

Tank sloshing in ship cargo is excited by ship motions, which induces impact load on tank wall and then affects the ship motion. Wave forces acting on ship hull and the retardation function are solved by using three-dimensional frequency domain theory and an impulse response function method based on the potential flow theory, and global ship motion is examined coupling with nonlinear tank sloshing which is simulated by viscous flow theory. Based on the open source Computational Fluid Dynamics （CFD） development platform Open Field Operation and Manipulation （OpenFOAM）, numerical calculation of ship motion coupled with tank sloshing is achieved and the corresponding numerical simulation and validation are carried out. With this method, the interactions of wave, ship body and tank sloshing are completely taken into consideration. This method has quite high efficiency for it takes advantage of potential flow theory for outer flow field and viscous flow theory for inside tank sloshing respectively. The numerical and experimental results of the ship motion agree well with each other.

关键词： Open Field Operation and Manipulation (OpenFOAM) time domain simulation tank sloshing and coupling effect,Impulse-Response Function (IRF)

Numerical simulation of rolling for 3-D ship with forward speed and nonlinear damping analysis

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Journal of Hydrodynamics 2013年第1期25卷 148-155页

作者： YANG Chun-lei ZHU Ren-chuan MIAO Guo-ping fan ju State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University

Strongly nonlinear characteristics of ship roll owing to viscous effect can be usually observed. To describe the nonlinear roll behavior, the CFD method has been frequently employed with obvious advantages compared with the traditional semi-empirical formula method in estimating the roll damping. Numerical simulations of free decay and forced rolling at various forward speeds and amplitudes for a 3-D ship hull are conducted in the present research to predict ship roll damping, in which a RANS solver is employed and a dynamic mesh technique is adopted and discussed in detail. Numerical results, including nonlinear flow characters around ships, rolling decay curves and damping coefficients, show that they are all in good agreement with available experimental data. The linear and nonlinear damping coefficients are estimated and analyzed by fitting with exponential functions for various rolling amplitudes, frequencies and speeds in the free decay simulations, and the damping coefficients are obtained by a polynomial fitting in the forced roll simulations. It is indicated that the damping coefficients increase with increasing rolling angle amplitude and velocity. It is also emphasized that the effect of forward speed is significant to roll damping and the nonlinear damping decreases with increasing velocity.

关键词： RANS method free decay forced roll nonlinear damping

一种伪装昆虫图像的前背景自动分割算法——ZDNet

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昆虫学报 2024年第8期67卷 1127-1136页

作者：范炬臣李小林任昊杰王荣张飞萍黄世国福建农林大学计算机与信息学院福州350002 智慧农林福建省高校重点实验室福州350002 福建农林大学林学院福州350002

【目的】昆虫常在色彩、纹理或形态上和背景相似,具有伪装性,识别难度大。本研究旨在探索基于深度学习的伪装昆虫前背景自动分割方法。【方法】将显著目标检测算法(salient object detection algorithm)、大模型图像分割算法(large-scal... 详细信息

【目的】昆虫常在色彩、纹理或形态上和背景相似,具有伪装性,识别难度大。本研究旨在探索基于深度学习的伪装昆虫前背景自动分割方法。【方法】将显著目标检测算法(salient object detection algorithm)、大模型图像分割算法(large-scale model-based image segmentation algorithm)以及伪装目标检测算法(camouflaged object detection algorithm)应用于伪装昆虫数据集,该数据集包括10类昆虫共1 900张图片;并进一步针对现有伪装目标检测算法的不足,提出了一种基于DGNet(deep-gradient network)的网络模型改进方法,即ZDNet(zoom-deep gradient network)。在构建该模型时,充分运用图像特征增强、交错图像金字塔、梯度诱导和跳跃式特征融合等技术。利用伪装目标检测公开数据集COD10K与CAMO构建了包含螽斯、蜘蛛等10个目昆虫的图像数据集,结合迁移学习进行网络训练,将经过训练的模型用于分割伪装昆虫。【结果】现有的伪装目标检测模型用于伪装昆虫前背景分割时,其分割性能明显优于显著目标检测模型和大模型分割图像。同时,ZDNet在性能上也明显优于现有的伪装目标检测算法,获得的S度量值、最大F度量值、平均F度量值、最大E度量值、平均E度量值和平均绝对误差(mean absolute error,MAE)分别为0.890, 0.865, 0.824, 0.966, 0.951和0.020。【结论】研究结果证明了ZDNet网络模型能够获得很好的伪装昆虫前背景分割结果,有利于提高昆虫识别的性能,也进一步拓宽了伪装目标检测方法的应用范围。

关键词：昆虫伪装目标检测深度学习图像分割深层梯度网络

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HULL GESTURE AND RESISTANCE PREDICTION OF HIGH-SPEED VESSELS

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Journal of Hydrodynamics 2011年第2期23卷 234-240页

作者： NI Chong-ben ZHU Ren-chuan MIAO Guo-ping fan ju School of Naval Architecture Ocean and Civil Engineering State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

Since trim and sinkage are significant while vessels are advancing forward with high speed, the predicted vessel resistance based on restrained model theory or experiment may not be real resistance of vessels during voyage. It is necessary to take the influence of hull gesture into account for oredicting the resistance of high-speed ship. In the present work the resistance problem of high speed ship is treated with the viscous flow theory, and the dynamic mesh technique is adopted to coincide with variation of hull gesture of high speed vessel on voyage. The simulation of the models of S60 ship and a trimaran moving in towing tank with high speed are conducted by using the above theory and technique. The corresponding numerical results are in good agreement with the experimental data. It indicates that the resistance prediction for high speed vessels should take hull gesture into consideration and the dynamic mesh method proposed here is effective in calculating the resistance of high speed vessels.

关键词： ship trim and sinkage dynamic mesh high-speed vessel resistance

BTG2 interference ameliorates high glucose-caused oxidative stress, cell apoptosis, and lipid deposition in HK-2 cells

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BIOCELL 2024年第9期48卷 1379-1388页

作者： Zhu, Wenjuan ju, Zhengzheng Cui, fan First Peoples Hosp Wuhu Dept Blood Transfus Wuhu 241000 Peoples R China First Peoples Hosp Wuhu Dept Clin Lab Wuhu 241000 Peoples R China

Objective: Diabetic nephropathy (DN) is a deleterious microangiopathy of diabetes, constituting a critical determinant of fatality in diabetic patients. This work is purposed to disclose the effects and modulatory mechanism of BTG anti-proliferation factor 2 (BTG2) during the pathological process of DN. Methods: BTG2 expression in kidney tissues of diabetic mice and high glucose (HG)-exposed human proximal tubular cell line HK-2 was assessed with Western blot and RT-qPCR. The diabetic mice model was constructed by streptozotocin injection and con fi rmed by the blood glucose level beyond 16.7 mmol/L. Hematoxylin and eosin (H&E) staining and measurement of kidney function hallmarks were conducted to assess kidney injury. Cell counting kit (CCK)-8 method and TUNEL assay appraised cell activity and apoptosis. Oil red O staining assayed lipid accumulation. Relevant commercial kits were used to estimate oxidative stress-related factors. Co-immunoprecipitation (Co-IP) assay testi fi ed the binding relationship of BTG2 with protein arginine methyltransferase 1 (PRMT1). Results: BTG2 expression was signi fi cantly raised in renal tissues of diabetic mice and HK-2 cells exposed to HG. BTG2 de fi ciency improved viability and extenuated the apoptosis, lipid deposition as well as oxidative stress in HK-2 cells following HG exposure. In addition, PRMT1 was also overexpressed in HK-2 cells exposed to HG. BTG2 interacted with PRMT1 and positively modulated PRMT1 expression. The effects of BTG2 interference on viability, apoptosis, lipid deposition, and oxidative stress in HG-challenged HK-2 cells were partially abrogated by PRMT1 overexpression. Conclusion: Altogether, BTG2 might aggravate HK-2 cell injury in response to HG by binding with PRMT1, providing a novel target for the therapeutic strategy of DN.

关键词： BTG2 Diabetic nephropathy Lipid deposition Oxidative stress PRMT1 PRMT1 GENE