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Intelligent Optimization of Particle-Jamming-Based Variable Stiffness Module Design Using a Grey-box Model Based on Virtual Work Principle
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作者 Hao Huang Zhenyun Shi +2 位作者 Ziyu Liu Tianmiao Wang Chaozong Liu 《Journal of Bionic Engineering》 CSCD 2024年第5期2324-2339,共16页
Soft grippers are favored for handling delicate objects due to their compliance but often have lower load capacities compared to rigid ones.Variable Stiffness Module(VSM)offer a solution,balancing flexibility and load... Soft grippers are favored for handling delicate objects due to their compliance but often have lower load capacities compared to rigid ones.Variable Stiffness Module(VSM)offer a solution,balancing flexibility and load capacity,for which particle jamming is an effective technology for stiffness-tunable robots requiring safe interaction and load capacity.Specific applica-tions,such as rescue scenarios,require quantitative analysis to optimize VSM design parameters,which previous analytical models cannot effectively handle.To address this,a Grey-box model is proposed to analyze the mechanical response of the particle-jamming-based VSM by combining a White-box approach based on the virtual work principle with a Black-box approach that uses a shallow neural network method.The Grey-box model demonstrates a high level of accuracy in predict-ing the VSM force-height mechanical response curves,with errors below 15%in almost 90%of the cases and a maximum error of less than 25%.The model is used to optimize VSM design parameters,particularly those unexplored combinations.Our results from the load capacity and force distribution comparison tests indicate that the VSM,optimized through our methods,quantitatively meets the practical engineering requirements. 展开更多
关键词 Grey-box model Neural network Variable stiffness module Particle jamming virtual work principle
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Joint decision-making of virtual module formation and scheduling considering queuing time
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作者 Liang Mei Liu Yue Shilun Ge 《Data Science and Management》 2023年第3期134-143,共10页
Formation and scheduling are the most important decisions in the virtual modular manufacturing system;however,the global performance optimization of the system may be sacrificed via the superposition of two independen... Formation and scheduling are the most important decisions in the virtual modular manufacturing system;however,the global performance optimization of the system may be sacrificed via the superposition of two independent decision-making results.The joint decision of formation and scheduling is very important for system design.Complex and discrete manufacturing enterprises such as shipbuilding and aerospace often comprise multiple tasks,processes,and parallel machines,resulting in complex routes.The queuing time of parts in front of machines may account for 90%of the production cycle time.This study established a weighted allocation model of a formation-scheduling joint decision problem considering queuing time in system.To solve this nondeterministic polynomial(NP)problem,an adaptive differential evolution-simulated annealing(ADE-SA)algorithm is proposed.Compared with the standard differential evolution(DE)algorithm,the adaptive mutation factor overcomes the disadvantage that the scale of DE’s differential vector is difficult to control.The selection strategy of the SA algorithm compensates for the deficiency that DE’s greedy strategy may fall into a local optimal solution.The comparison results of four algorithms of a series of random examples demonstrate that the overall performance of ADE-SA is superior to the genetic algorithm,and average iteration,maximum completion time,and move time are 24%,11%,and 7%lower than the average of other three algorithms,respectively.The method can generate the joint decision-making scheme with better overall performance,and effectively identify production bottlenecks through quantitative analysis of queuing time. 展开更多
关键词 Joint decision-making Queue time virtual module Hybrid algorithm
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A Practical Online Approach to Protecting Kernel Heap Buffers in Kernel Modules
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作者 Donghai Tian Xiaoqi Jia +2 位作者 Junhua Chen Changzhen Hu Jingfeng Xue 《China Communications》 SCIE CSCD 2016年第11期143-152,共10页
Heap overflow attack is one of the major memory corruption attacks that have become prevalent for decades. To defeat this attack,many protection methods are proposed in recent years. However,most of these existing met... Heap overflow attack is one of the major memory corruption attacks that have become prevalent for decades. To defeat this attack,many protection methods are proposed in recent years. However,most of these existing methods focus on user-level heap overflow detection. Only a few methods are proposed for kernel heap protection. Moreover,all these kernel protection methods need modifying the existing OS kernel so that they may not be adopted in practice. To address this problem,we propose a lightweight virtualization-based solution that can protect the kernel heap buffers allocated for the target kernel modules. The key idea of our approach is to combine the static binary analysis and virtualization technology to trap a memory allocation operation of the target kernel module,and then add one secure canary word to the end of the allocated buffer. After that,a monitor process is launched to check the integrity of the canaries. The evaluations show that our system can detect kernel heap overflow attacks effectively with minimal performance cost. 展开更多
关键词 kernel heap overflow virtualization technology kernel module
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Oxygenation promoting Se-coordination of amorphous adjacent Nb-Nb diatomic pairs for high-performance sodium-ion hybrid capacitors
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作者 Wenxiu He Fanyan Zeng +4 位作者 Bowen Liao Qincheng Zheng Dui Ma Meilan Xie Yang Pan 《Journal of Energy Chemistry》 2026年第1期474-483,I0011,共11页
Transition metal selenides as sodium-ion hybrid capacitor(SIHC)anodes still suffer from amorphization difficulties and capacity degradation triggered by polyselenide dissolution.Herein,an atomistic amorphous strategy ... Transition metal selenides as sodium-ion hybrid capacitor(SIHC)anodes still suffer from amorphization difficulties and capacity degradation triggered by polyselenide dissolution.Herein,an atomistic amorphous strategy is proposed to construct adjacent Nb-Nb diatomic pairs with Se/O-coordination(Se4-Nb2-O2)in N-doped carbon-confined amorphous selenide clusters(a-Nb-Se/O@NC).Synergistic carbon confinement and hydrothermal oxygenation induce amorphization of Nb–Se bonds,eliminating crystalline rigidity while creating isotropic dual-ion transport channels and high-density active sites enriched with dangling bonds,thereby enhancing structural integrity and Na+storage capacity.The unique Se/O-coordinated Nb-Nb diatomic configuration establishes an electron-delocalized system,where the low electronegativity of Se counterbalances electron withdrawal from coordinated O at Nb centers.These strengthen d-p orbital hybridization,reduce Na+adsorption energy,and optimize charge transfer pathways and reaction kinetics in the amorphous clusters.Electrochemical tests reveal that the a-Nb-Se/O@NC anode delivers a high reversible capacity of 312.57 mAh g^(−1)and exceptional cyclic stability(103%capacity retention)after 5000 cycles at 10.0 A g^(−1).Assembled SIHCs achieve outstanding energy/power densities(207.1 Wh kg^(−1)/18966 W kg^(−1)),surpassing most amorphous and crystalline counterparts.This work provides methodological insights for the design of electrodes in high-power storage devices through atomic modulation and electronic optimization of amorphous selenides. 展开更多
关键词 Amorphous selenide clusters Adjacent Nb-Nb diatomic pairs Se/o hetero-coordination Microstructural modulation Sodium-ion hybrid capacitors
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Virtually Baer模
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作者 王永铎 陈玉华 《兰州理工大学学报》 北大核心 2025年第1期145-149,共5页
引入virtually Baer模的概念,举例说明virtually Baer模是Baer模的真推广,给出了在一定条件下virtually Baer模对直和项的封闭性,讨论了virtually Baer模与GSIP模、广义SSIP模之间的关系,由此给出了半单artinian环及右V-环新的刻画.
关键词 virtually Baer模 Baer模 GSIP模 半单artinian环 V-环
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A New DC Side Capacitance Voltages Balancing Method for Three-level Inverters Based on Hybrid Space Vector Modulation 被引量:6
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作者 Fan Bishuang Tan Guanzheng +1 位作者 Fan Shaosheng Deng zelin 《中国电机工程学报》 EI CSCD 北大核心 2012年第27期I0017-I0017,共1页
Three-level neutral point clamped(NPC)inverters have been widely applied in the high voltage and high power drive fields.The capacitance voltage balancing algorithm is a hot topic that many specialists and scholars ha... Three-level neutral point clamped(NPC)inverters have been widely applied in the high voltage and high power drive fields.The capacitance voltage balancing algorithm is a hot topic that many specialists and scholars have been working on.V arious capacitance voltage balancing strategies have been studied,in which the redundant short vectors are not fully utilized.In order to increase the capacitance voltage control effect of the short vectors,a new algorithm is proposed. 展开更多
关键词 Three-level Inverter virtual vector Hybrid Space Vector modulation Capacitance Voltage Balancing Time distribution factor
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Thickness-modulated in-plane Bi2O2Se homojunctions for ultrafast high-performance photodetectors 被引量:4
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作者 Cheng-Yun Hong Gang-Feng Huang +2 位作者 Wen-Wen Yao Jia-Jun Deng Xiao-Long Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期363-369,共7页
Bi2O2Se thin film could be one of the promising material candidates for the next-generation electronic and optoelectronic applications. However, the performance of Bi2O2Se thin film-based device is not fully explored ... Bi2O2Se thin film could be one of the promising material candidates for the next-generation electronic and optoelectronic applications. However, the performance of Bi2O2Se thin film-based device is not fully explored in the photodetecting area. Considering the fact that the electrical properties such as carrier mobility, work function, and energy band structure of Bi2O2Se are thickness-dependent, the in-plane Bi2O2Se homojunctions consisting of layers with different thicknesses are successfully synthesized by the chemical vapor deposition(CVD) method across the terraces on the mica substrates,where terraces are created in the mica surface layer peeling off process. In this way, effective internal electrical fields are built up along the Bi2O2Se homojunctions, exhibiting diode-like rectification behavior with an on/off ratio of 102, what is more, thus obtained photodetectors possess highly sensitive and ultrafast features, with a maximum photoresponsivity of 2.5 A/W and a lifetime of 4.8 μs. Comparing with the Bi2O2Se uniform thin films, the photo-electric conversion efficiency is greatly improved for the in-plane homojunctions. 展开更多
关键词 Bi2o2Se in-plane homojunction thickness modulation PHoToDETECToRS
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TPM Context Manager and Dynamic Configuration Management for Trusted Virtualization Platform 被引量:1
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作者 QIN Yu FENG Dengguo LIU Chunyong 《Wuhan University Journal of Natural Sciences》 CAS 2008年第5期539-546,共8页
It is absolutely critical that trusted configuration management which significantly affects trust chain establishment, sealing storage and remote attestation, especially in trusted virtualization platform like Xen who... It is absolutely critical that trusted configuration management which significantly affects trust chain establishment, sealing storage and remote attestation, especially in trusted virtualization platform like Xen whose system configuration changes easily. TPM (trusted platform module) context manager is presented to carry out dynamic configuration management for virtual machine. It manages the TPM command requests and VM (virtual machine) configurations. The dynamic configuration representa- tion method based on Merkle hash tree is explicitly proposed against TCG (trusted computing group) static configuration representation. It reflects the true VM status in real time even if the configuration has changed, and it eliminates the invalidation of configuration representation, sealing storage and remote attestation. TPM context manager supports TCG storage protection, remote attestation etc, which greatly enhances the security on trusted virtualization platform. 展开更多
关键词 trusted computing TPM (trusted platform module trusted virtualization configuration representation configuration management
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小型PLC远程I/O模块的DC/DC供电变换器设计
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作者 王哲 《日用电器》 2025年第10期61-65,共5页
针对工业自动化系统中小型PLC(Programmable Logic Controller,可编程逻辑控制器)远程I/O模块的供电需求,本文提出一种基于PWM(Pulse Width Modulation,脉冲宽度调制)控制的12~5 V降压型DC/DC变换器。通过高频PWM信号驱动MOSFET开关管,... 针对工业自动化系统中小型PLC(Programmable Logic Controller,可编程逻辑控制器)远程I/O模块的供电需求,本文提出一种基于PWM(Pulse Width Modulation,脉冲宽度调制)控制的12~5 V降压型DC/DC变换器。通过高频PWM信号驱动MOSFET开关管,采用PI闭环补偿算法对误差进行调节,保证输出电压稳定性,最后制作了实验样机,验证了理论分析的正确性。 展开更多
关键词 PLC远程i/o模块 DC/DC 闭环补偿算法
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A Cluster-Based Virtual Cooperative MIMO Transmission Scheme
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作者 Hongfang Lyu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第3期89-96,共8页
The most essential issue is to ensure the reliability of data transmission during wireless communication and reduce energy consumption of the network for supervising the environmental state using wireless sensor netwo... The most essential issue is to ensure the reliability of data transmission during wireless communication and reduce energy consumption of the network for supervising the environmental state using wireless sensor network(WSN).Here,a cluster-based virtual cooperative MIMO transmission scheme(CVCM) is suggested,The proposed scheme involves optimization of cooperative nodes and the modulation speed dynamically as per the distance space the cluster head and the sink node,in order to minimize the communication energy consumption of each virtual MIMO unit and the convergence node,thereby reducing the capacity consumption of the entire network.Simulation and experimental results demonstrate the effectiveness of CVCM in reducing network energy consumption,increasing the network lifetime and improving data reception performance of the base station. 展开更多
关键词 CLUSTER virtual CooPERATIVE MIMo dynamic CoNFIGURATIoN modulATIoN SPEED
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基于AutoCAD参数的男装O型夹克样板自动生成 被引量:1
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作者 冯芳慧 张皋鹏 《毛纺科技》 北大核心 2025年第1期68-74,共7页
为探索AutoCAD参数化设计在休闲男装品类中大规模个性化定制中的适用性,以休闲男装经典款式之一的O型夹克为研究对象,采用椭圆弧及双圆弧拟合原理绘制袖窿及领口弧线,构建O型夹克结构的参数化模型,主要包括衣身原型各对象的标注约束及... 为探索AutoCAD参数化设计在休闲男装品类中大规模个性化定制中的适用性,以休闲男装经典款式之一的O型夹克为研究对象,采用椭圆弧及双圆弧拟合原理绘制袖窿及领口弧线,构建O型夹克结构的参数化模型,主要包括衣身原型各对象的标注约束及几何约束、原型初始尺寸及参数调整量;然后根据基本样板的结构特征调整参数值,自动生成变款纸样;最后借助CLO3D软件虚拟展示成衣效果并验证O型夹克参数化结构模型的准确性。结果验证了AutoCAD参数化功能在休闲男装品类个性化定制中的适用性,提高了参数化在男装设计中的应用广度以及在个性化定制中的快速反应能力。 展开更多
关键词 AUToCAD 参数化模型 服装制版 男装o型夹克 虚拟试衣
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Research on performance testing of radio fuse based on virtual separation technology
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作者 许爱国 贾立新 +1 位作者 杨晋伟 姜志保 《Journal of Measurement Science and Instrumentation》 CAS 2013年第4期339-342,共4页
The conception of virtual separation technology about high low frequency of electronic module was put forward based on the analysis of tactical performance testing of radio fuse.By means of the principle of fuse Doppl... The conception of virtual separation technology about high low frequency of electronic module was put forward based on the analysis of tactical performance testing of radio fuse.By means of the principle of fuse Doppler signal acquisition and injection,the high low frequency of electronic module was virtually separated,and one of important parameters—burst height of radio fuse is tested precisely. 展开更多
关键词 virtual separation tactical performance electronic module Doppler signal acquisition and injection
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VARIABLE-RATE MULTIUSER DIVERSITY IN CORRELATED MIMO CHANNEL VIA VIRTUAL CHANNEL REPRESENTATION
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作者 Tang Lan You Xiaohu Liang Yingchang 《Journal of Electronics(China)》 2006年第3期332-337,共6页
This paper studies the multiuser diversity with constellation selection based on a virtual representation of realistic Multiple Input Multiple Output (MIMO) correlated channels. To realize multiuser diversity in slo... This paper studies the multiuser diversity with constellation selection based on a virtual representation of realistic Multiple Input Multiple Output (MIMO) correlated channels. To realize multiuser diversity in slow fading channels, random beamforming is adopted. Random beamforming matrix exploiting virtual channel representation is constructed, which can match the channel matrix of the desired user better. Sirnultaneously, adaptive coded modulation is applied to each sub-channel of the selected user to improve the system performance further. 展开更多
关键词 Multiple Input Multiple output (MIMo Correlated channel virtual channel BEAMFoRMING Multiuser diversity Adaptive modulation
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Improved VSVPWM Modulation Method for Three-level NPC Inverter in Rural Power Grid
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作者 Li Ran Fang Jun-long +1 位作者 Wang Jun-fu Wang Guang-ya 《Journal of Northeast Agricultural University(English Edition)》 CAS 2021年第1期90-96,共7页
With the acceleration of agricultural electrification,a lot of nonlinear and shock loads appear in the rural power grid,and the resulting harmonic and reactive currents pollute the rural power grid more and more serio... With the acceleration of agricultural electrification,a lot of nonlinear and shock loads appear in the rural power grid,and the resulting harmonic and reactive currents pollute the rural power grid more and more seriously.To solve the above problem,three-level neutral point clamped(NPC)inverters have been widely used,but their development is greatly restricted by the defect of neutral point voltage imbalance.In this paper,an improved virtual space vector pulse width modulation(VSVPWM)was proposed.Firstly,the mathematical models of various space vectors were established,and the influence of various space vectors on neutral point voltage was analyzed.The sum of the vector current at the neutral point was zero and the voltage control at the neutral point was completed by.introducing the time offset into different switching times of the redundant small vector.This method was simple in design and avoided the redundant calculation of the traditional VSVPWM method and tedious switch sequence design.This balancing control strategy could greatly reduce the influence of virtual vectors on neutral point voltage and effectively control the low-frequency oscillation of neutral point voltage.The validity of the method was verified by establishing a matlab simulation model. 展开更多
关键词 rural power grid virtual space vector pulse width modulation neutral point clamped inverter neutral point voltage
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vCerberus:A DRTM System Based on Virtualization Technology
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作者 CHEN Wenzhi ZHANG Zhipeng YANG Jianhua HE Qinming 《Wuhan University Journal of Natural Sciences》 CAS 2010年第3期185-189,共5页
This paper presents vCerberus, a novel hypervisor to provide trusted and isolated code execution within virtual domains vCerberus is considerably tiny, while allowing secure sensitive codes to be executed in an isolat... This paper presents vCerberus, a novel hypervisor to provide trusted and isolated code execution within virtual domains vCerberus is considerably tiny, while allowing secure sensitive codes to be executed in an isolated circumstance from the virtual ddmain, and can be attested by a remote party in an efficient way. These properties will be guaranteed even if the vip operating system is malicious. This protects the secure sensitive codes against the malicious codes in the vip OS, e.g., the kernel rootkits. We present an approach to dynamically measure and isolate the launch environment on the virtual machines based on the para-virtualization technology and a novel virtualization of trusted platform module (TPM). Our performance experiment result shows that the overhead introduced by vCerberus is minimized; the performance of the launch environment in vCerberus is as competitive as the vip OS running on mainstream hypervisors. 展开更多
关键词 trusted computing para-virtualization dynamic root of trust for measurement (DRTM) trusted platform module (TPM)
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Transmission Facility Detection with Feature-Attention Multi-Scale Robustness Network and Generative Adversarial Network
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作者 Yunho Na Munsu Jeon +4 位作者 Seungmin Joo Junsoo Kim Ki-Yong Oh Min Ku Kim Joon-Young Park 《Computer Modeling in Engineering & Sciences》 2025年第7期1013-1044,共32页
This paper proposes an automated detection framework for transmission facilities using a featureattention multi-scale robustness network(FAMSR-Net)with high-fidelity virtual images.The proposed framework exhibits thre... This paper proposes an automated detection framework for transmission facilities using a featureattention multi-scale robustness network(FAMSR-Net)with high-fidelity virtual images.The proposed framework exhibits three key characteristics.First,virtual images of the transmission facilities generated using StyleGAN2-ADA are co-trained with real images.This enables the neural network to learn various features of transmission facilities to improve the detection performance.Second,the convolutional block attention module is deployed in FAMSR-Net to effectively extract features from images and construct multi-dimensional feature maps,enabling the neural network to perform precise object detection in various environments.Third,an effective bounding box optimization method called Scylla-IoU is deployed on FAMSR-Net,considering the intersection over union,center point distance,angle,and shape of the bounding box.This enables the detection of power facilities of various sizes accurately.Extensive experiments demonstrated that FAMSRNet outperforms other neural networks in detecting power facilities.FAMSR-Net also achieved the highest detection accuracy when virtual images of the transmission facilities were co-trained in the training phase.The proposed framework is effective for the scheduled operation and maintenance of transmission facilities because an optical camera is currently the most promising tool for unmanned aerial vehicles.This ultimately contributes to improved inspection efficiency,reduced maintenance risks,and more reliable power delivery across extensive transmission facilities. 展开更多
关键词 object detection virtual image transmission facility convolutional block attention module Scylla-IoU
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FPSO大型模块吊装有限元分析
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作者 孔国照 冯晓华 《船海工程》 北大核心 2025年第6期48-52,65,共6页
以某FPSO的电气间模块整体吊装作为研究对象,采用DNV规范确定计算载荷,运用SACS软件构建包含吊索具和模块在内的整体吊装有限元模型,通过施加虚拟力偶模拟模块重心偏移影响。计算模块吊装过程当中的结构响应及各吊耳的实际载荷情况,结... 以某FPSO的电气间模块整体吊装作为研究对象,采用DNV规范确定计算载荷,运用SACS软件构建包含吊索具和模块在内的整体吊装有限元模型,通过施加虚拟力偶模拟模块重心偏移影响。计算模块吊装过程当中的结构响应及各吊耳的实际载荷情况,结果表明,模块在吊装过程中的整体结构强度和变形均满足规范标准要求,有限元分析为大型模块整体吊装方案的可行性提供依据。 展开更多
关键词 大型模块 吊装 虚拟力偶 重心偏移 有限元分析
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Tuning of the Metal-Insulator Transition in Nd-Doped Bilayer Nickelate La_(3)Ni_(2)O_(7)Thin Films
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作者 Fang-Hui Zhu Xue-Yan Wang +7 位作者 Ting-Na Shao Qiang Zhao Wen-Long Yang Cheng-Xue Chen Mei-Ling Yan Rui-Fen Dou Chang-Min Xiong Jia-Cai Nie 《Chinese Physics Letters》 2025年第6期178-190,共13页
Recent studies have successfully demonstrated high-Tc superconductivity in bilayer nickelate La3Ni2O7.However,research on modulating the structural and transport characteristics of La3Ni2O7 films by applying“chemical... Recent studies have successfully demonstrated high-Tc superconductivity in bilayer nickelate La3Ni2O7.However,research on modulating the structural and transport characteristics of La3Ni2O7 films by applying“chemical”compressive pressure through cation substitution is still limited.Here,we address this issue in the La_(3−x)Nd_(x)Ni_(2)O_(7)(x=0,1.0,1.5,2.0,and 2.5)thin film samples.It was found that using Nd3+with a smaller radius instead of La3+can reduce the c-axis lattice constant and shift the metal-insulator transition(MIT)temperature TMIT.To probe the origin of the MIT at cryogenic temperatures,experimental measurements of magnetoresistance were conducted,and theoretical analysis was carried out using the Kondo model,Hikami-Larkin-Nagaoka equation,and other methods.The results indicate that as Nd doping rises,the contributions of the Kondo effect and two-dimensional weak localization(WL)first decrease and then increase.The total contribution of WL and the Kondo effect in the mid-doped La_(1.5)Nd_(1.5)Ni_(2)O_(7)sample was the smallest,which to some extent explains the changes in TMIT.The Kondo effect dominates in other La_(3−x)Nd_(x)Ni_(2)O_(7)(x=0,1.0,2.0,and 2.5)samples.This work demonstrates that cation doping has a significant impact on bilayer nickelates,providing experimental evidence for understanding the physical mechanism of the MIT in bilayer nickelates. 展开更多
关键词 bilayer nickelate thin films La Ni o modulating structural transport characteristics high Tc superconductivity Nd doping cation substitution metal insulator transition
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修改客户操作系统优化KVM虚拟机的I/O性能 被引量:13
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作者 张彬彬 汪小林 +4 位作者 杨亮 赖荣凤 王振林 罗英伟 李晓明 《计算机学报》 EI CSCD 北大核心 2010年第12期2312-2320,共9页
目前,运行在虚拟机上的客户操作系统(vipOS)是面向物理机器开发的普通操作系统,其中存在不适应虚拟化环境的因素,影响虚拟机的I/O性能.作者通过测试发现了影响虚拟机I/O性能的一些问题,针对这些问题提出了优化方法:一方面,通过合并客... 目前,运行在虚拟机上的客户操作系统(vipOS)是面向物理机器开发的普通操作系统,其中存在不适应虚拟化环境的因素,影响虚拟机的I/O性能.作者通过测试发现了影响虚拟机I/O性能的一些问题,针对这些问题提出了优化方法:一方面,通过合并客户操作系统中连续的I/O指令,降低虚拟机的时钟中断频率,从而降低环境切换的开销;另一方面,消除客户操作系统中的冗余操作,包括在虚拟化环境下无效的函数、冗余的I/O调度以及虚拟网卡驱动对NAPI的支持,使虚拟机只执行必要的操作,从而提高系统的性能. 展开更多
关键词 i/o虚拟化 KVM 性能测试 优化
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基于单根I/O虚拟化的多根I/O资源池化方法 被引量:8
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作者 王展 曹政 +4 位作者 刘小丽 苏勇 李强 安学军 孙凝晖 《计算机研究与发展》 EI CSCD 北大核心 2015年第1期83-93,共11页
虚拟化技术在为现代数据中心提供高效的服务器整合能力和灵活的应用部署能力的同时,也对数据中心服务器的I/O系统设计提出了新的需求,现有I/O资源与服务器紧密绑定的I/O体系架构将产生成本上升、资源冗余、I/O连线复杂化等一系列问题.... 虚拟化技术在为现代数据中心提供高效的服务器整合能力和灵活的应用部署能力的同时,也对数据中心服务器的I/O系统设计提出了新的需求,现有I/O资源与服务器紧密绑定的I/O体系架构将产生成本上升、资源冗余、I/O连线复杂化等一系列问题.针对上述问题,提出了一种基于单根I/O虚拟化协议(single root I/O virtualization,SR-IOV)的多根I/O资源池化方法:基于硬件的多根域间地址和ID映射机制,实现了多个物理服务器对同一I/O设备的共享复用,有效减少单体服务器所需的设备数量和连线数量,并进一步提高服务器密度;同时提出虚拟I/O设备热插拔技术和多根共享管理机制,实现了虚拟I/O资源在服务器间的实时动态分配,提高资源的利用效率.提出的方法在可编程逻辑器件(fieid-programmable gate array,FPGA)原型系统中进行了验证,其评测表明,方法能够在实现多根I/O虚拟化共享的同时,保证各个根节点服务器获得近乎本地直连设备的I/O性能. 展开更多
关键词 数据中心 服务器 i/o虚拟化 i/o资源池 PCIe兼容
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