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Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin Zeng Le Wang Wenwu Zhang Gang Li Xing Cheng Peiqiang su yong Wan Xiang Li Department of Spine surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury

A Time-Domain Numerical Simulation for Free Motion Responses of Two Ships Advancing in Head Waves

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China Ocean Engineering 2024年第3期38卷 519-530页

作者： PAN su-yong CHENG yong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The constant panel method within the framework of potential flow theory in the time domain is developed for solving the hydrodynamic interactions between two parallel ships with forward *** solving problems within a time domain framework,the free water surface needs to simultaneously satisfy both the kinematic and dynamic boundary conditions of the free water *** provides conditions for adding artificial damping *** the Runge−Kutta method to solve equations related to *** upwind differential scheme is used in the present method to deal with the convection terms on the free surface to prevent waves *** the comparison with the available experimental data and other numerical methods,the present method is proved to have good mesh convergence,and satisfactory results can be *** constant panel method is applied to calculate the hydrodynamic interaction responses of two parallel ships advancing in head *** simulations are conducted on the effects of forward speed,different longitudinal and lateral distances on the motion response of two modified Wigley ships in head *** further investigations are conducted on the effects of different ship types on the motion response.

关键词： ship motions time domain simulation forward speed different distances wave loads

基于SE注意力多源域对抗网络的射频指纹识别

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计算机科学 2025年第1期52卷 412-419页

作者：苏超然张大龙黄勇董安郑州大学网络空间安全学院郑州450002

射频指纹利用射频前端的硬件特征作为标识符对设备进行识别。针对现有射频指纹识别研究忽略接收机硬件特性的干扰,导致模型在不同接收机设备上泛化性较差的问题,提出一种基于SE(Squeeze-and-Excitation)注意力多源域对抗网络的射频指纹... 详细信息

射频指纹利用射频前端的硬件特征作为标识符对设备进行识别。针对现有射频指纹识别研究忽略接收机硬件特性的干扰,导致模型在不同接收机设备上泛化性较差的问题,提出一种基于SE(Squeeze-and-Excitation)注意力多源域对抗网络的射频指纹识别方法。该方法采用多个源域有标签数据和少量目标域无标签数据进行对抗训练以提取与接收机域无关的特征;融合SE注意力机制增强模型对发送机射频指纹特征的学习能力;结合极少量目标域有标签数据对模型参数进行微调,进一步提高发送机识别性能。在Wisig公开数据集上的实验结果表明:该方法在跨接收机场景下可有效识别发送机设备,平均准确率可达83.1%;加入少量有标签数据微调后平均准确率可进一步提高至93.1%。

关键词：射频指纹识别多源域对抗深度学习物理层安全 SE注意力机制

TDOA estimation of dual-satellites interference localization based on blind separation

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Journal of Systems Engineering and Electronics 2019年第4期30卷 696-702页

作者： su Ting GAO yong College of Electronics and Information Engineering Sichuan University

The time difference of arrival(TDOA)estimation plays a crucial role in the accurate localization of the satellite interference *** the dual-satellites interference source localization system,the target signal from the adjacent satellite is likely to be interfered by the normal communication signal with the same ***,the signal to noise ratio(SNR)of the target signal would become too low,and the TDOA estimation through cross-correlation processing would be unreliable or even *** paper proposes a technique based on blind separation to solve the co-channel interference problem,where separation of the mixed signal can be carried out by the particle filter(PF)*** experimental results show that the proposed method could achieve more accurate TDOA *** measured data obtained by using the software radio platform at 915 MHz and 2 GHz respectively verify the effectiveness of the proposed method.

关键词： time difference of arrival(TDOA) co-channel interference blind separation particle filter(PF)

Simulation of water entry of an elastic wedge using the FDS scheme and HCIB method

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Journal of Hydrodynamics 2013年第3期25卷 450-458页

作者： shin Sangmook BAE sung yong Department of Naval Architecture and Marine Systems Engineering Pukyong National University Busan608-737 Korea

The hydroelasticity of water entry of an elastic wedge is simulated using a code developed using the flux-difference splitting scheme for immiscible and incompressible fluids and the hybrid Cartesian/immersed boundary method. The free surface is regarded as a moving contact discontinuity and is captured without any additional treatment along the interface. Immersed boundary nodes are distributed inside a fluid domain based on the edges that cross an instantaneous body boundary. Dependent variables are reconstructed at each immersed boundary node with the help of an interpolation along a local normal line for providing a boundary condition for a discretized flow problem. A dynamic beam equation is used for modeling the elastic deformation of a wedge. The developed code is validated through comparisons with other experimental and computational results for a free-falling wedge. The effects of the elastic deformation of the wedge on the pressure fields and time histories of the impact force are investigated in relation to the stiffness and density of the structure. Grid independence test is carried out for the computed time history of the force acting on an elastic wedge.

关键词： hydroelasticity free surface capturing non-boundary conforming method dynamic beam equation free falling impactforce

Analytic derivation of Monin-Obukhov similarity function for open atmospheric surface layer

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Science China(Physics,Mechanics & Astronomy) 2021年第3期64卷 73-83页

作者： yong Ji Zhen-su She State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing100871China

The Monin-Obukhov(MO)similarity functionφm of the atmospheric surface layer(ASL)describing the deviation from the log law of the canonical turbulent boundary layer because of thermal stratification has been traditionally determined *** study presents a unified analytic expression derived from a symmetry-based theory of wall turbulence,called structural ensemble dynamics(SED),which postulates a generalized dilation symmetry principle expressing the effect of the wall on turbulence,leading to an analytic multi-regimes expression for the mixing *** ASL in unstable and stable conditions(i.e.,UC and SC),a unified two-regime formula of the mixing length is proposed,leading to aφm,similar to the Businger-Dyer(BD)formula;with a simplified model energy balance equation,φm is completely specified with no free ***,the theory allows the study of the open ASL’s underlying additional physical processes such as bottom-up or top-down flux due to pressure variations *** that Tp is decomposed into shear-like and buoyancy-like components,we propose new explanations for two important features of typical ASL:a significantly smaller Karman constant of 0.36 and a varyingφm for SC mean speed *** theory is validated by the data obtained at Kansas and also at Qingtu Lake Observation Array in Northern China for a variety of heat flux *** conclusion,due to pressure variations,we assert that ASL is intrinsically open and that the current theory offers a new basis for its quantification.

关键词： Monin-Obukhov similarity theory open atmospheric surface layer boundary layer turbulence symmetry-based analysis

Cross-Domain Bilateral Access Control on Blockchain-Cloud Based Data Trading System

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 671-688页

作者： Youngho Park su Jin shin Sang Uk shin Electronics and Information Communications Research Center Pukyong National UniversityBusan48513Republic of Korea Department of Information Security Graduate SchoolPukyong National UniversityBusan48513Republic of Korea Division of Computer Engineering Pukyong National UniversityBusan48513Republic of Korea

Data trading enables data owners and data requesters to sell and purchase *** the emergence of blockchain technology,research on blockchain-based data trading systems is receiving a lot of ***,to reduce the on-chain storage cost,a novel paradigm of blockchain and cloud fusion has been widely considered as a promising data trading ***,the fact that data can be used for commercial purposes will encourage users and organizations from various fields to participate in the data *** the data marketplace,it is a challenge how to trade the data securely outsourced to the external cloud in a way that restricts access to the data only to authorized users across multiple *** this paper,we propose a cross-domain bilateral access control protocol for blockchain-cloud based data trading *** consider a system model that consists of domain authorities,data senders,data receivers,a blockchain layer,and a cloud *** proposed protocol enables access control and source identification of the outsourced data by leveraging identity-based cryptographic *** the proposed protocol,the outsourced data of the sender is encrypted under the target receiver’s identity,and the cloud provider performs policy-match verification on the authorization tags of the sender and receiver generated by the identity-based signature ***,data trading can be achieved only if the identities of the data sender and receiver simultaneously meet the policies specified by each *** demonstrate efficiency,we evaluate the performance of the proposed protocol and compare it with existing studies.

关键词： Bilateral access control blockchain data sharing policy-match

Time-Domain Higher-Order Boundary Element Method for Simulating High Forward-Speed Ship Motions in Waves

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China Ocean Engineering 2024年第5期38卷 904-914页

作者： ZHOU Xiao-guo CHENG yong PAN su-yong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

The hydrodynamic performance of a high forward-speed ship in obliquely propagating waves is numerically examined to assess both free motions and wave field in comparison with a low forward-speed *** numerical model is based on the time-domain potential flow theory and higher-order boundary element method,where an analytical expression is completely expanded to determine the base-unsteady coupling flow imposed on the moving condition of the *** ship in the numerical model may possess different advancing speeds,***,low speed,and high *** role of the water depth,wave height,wave period,and incident wave angle is analyzed by means of the accurate numerical *** is found that the resonant motions of the high forward-speed ship are triggered by comparison with the stationary *** specifically,a higher forward speed generates a V-shaped wave region with a larger elevation,which induces stronger resonant motions corresponding to larger wave *** shoaling effect is adverse to the motion of the low-speed ship,but is beneficial to the resonant motion of the high-speed *** waves obliquely propagate toward the ship,the V-shaped wave region would be broken due to the coupling effect between roll and pitch *** is also demonstrated that the maximum heave motion occurs in beam seas for stationary cases but occurs in head waves for high ***,the variation of the pitch motion with period is hardly affected by wave incident angles.

关键词： high forward speed oblique incident waves ship motion higher-order boundary element method time domain wave field

Hydraulic experiment on mushroom head in bottom-blown smelting furnace

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Journal of Iron and Steel Research International 2017年第5期24卷 490-494页

作者： Fu-yong su Zhi Wen School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

There are many bottom-blown smelting furnaces in metallurgical industry. When oxygen or air sprays from the jet nozzle into the bottom of the furnace, the melting phase will be frozen and a hemispherical porous zone with a mushroom head shape will be formed around the nozzle. The mushroom head can pro- tect the jet nozzle and mitigate the liquid spray on the surface of melt. In order to analyze the formation process of a mushroom head in the bottom-blown smelting furnaces, a hydraulic experiment system was designed and the formation of the mushroom head was investigated by hydraulic experiment. The hydrau- lic experiment results show that the formation process is mainly divided into generating crushing genera- ting process and stable mushroom head generation process. The formation of stable mushroom head re- quires certain thermodynamic condition and water splash is more intense without a mushroom head than with a mushroom head. The size, porosity and diameter of the mushroom head are affected by the flow rate, temperature and heat capacity of the bottom-blowing gas and the temperature of the superheat and the physical parameters of the melt.

关键词： Bottom-blown smelting furnace Mushroom head Hydraulic experiment Thermal equilibrium Similarity criterion