检索结果-内蒙古大学图书馆

Write-Optimized B^(+) Tree Index technology for Persistent Memory

Journal of Computer science & technology 2021年第5期36卷 1037-1050页

作者： Rui-Xiang Ma Fei Wu Bu-Rong Dong Meng Zhang Wei-Jun Li Chang-Sheng Xie Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430070China Key Laboratory of Information Storage System Ministry of Education of ChinaWuhan 430070China Engineering Research Center of Data Storage Systems and Technology Huazhong University of Science and Technology Wuhan 430070China School of Computer Science and Technology Huazhong University of Science and TechnologyWuhan 430070China Shenzhen DAPU Microelectronics Co. LtdShenzhen 518116China

Due to its low latency,byte-addressable,non-volatile,and high density,persistent memory(PM)is expected to be used to design a high-performance storage ***,PM also has disadvantages such as limited endurance,thereby proposing challenges to traditional index technologies such as B(+)tree.B(+)tree is originally designed for dynamic random access memory(DRAM)-based or disk-based systems and has a large write amplification *** high write amplification is detrimental to a PM-based *** paper proposes WO-tree,a write-optimized B(+)tree for ***-tree adopts an unordered write mechanism for the leaf nodes,and the unordered write mechanism can reduce a large number of write operations caused by maintaining the entry order in the leaf *** the leaf node is split,WO-tree performs the cache line flushing operation after all write operations are completed,which can reduce frequent data flushing ***-tree adopts a partial logging mechanism and it only writes the log for the leaf *** inner node recognizes the data inconsistency by the read operation and the data can be recovered using the leaf node information,thereby significantly reducing the logging ***,WO-tree adopts a lock-free search for inner nodes,which reduces the locking overhead for concurrency *** evaluate WO-tree using the Yahoo!Cloud Serving Benchmark(YCSB)*** with traditional B(+)tree,wB-tree,and Fast-Fair,the number of cache line flushes caused by WO-tree insertion operations is reduced by 84.7%,22.2%,and 30.8%,respectively,and the execution time is reduced by 84.3%,27.3%,and 44.7%,respectively.

关键词： persist memory B^(+)tree write amplication consistency YCSB(Yahoo!Cloud Serving Benchmark)

来源：评论

学校读者我要写书评

暂无评论

Research on Electromagnetic Launch Control system Based on ARM and FPGA Architecture 2

Research on Electromagnetic Launch Control System Based on A...

引用

2nd International Conference on Computational Modeling, Simulation and Data Analysis, CMSDA 2022

作者： Zhao, Xiaodong Li, Wantong Li, Haiyuan Nanjing University of Science and Technology National Key Laboratory of Transient Physics Nanjing China Unmanned System Research Institute Northwestern Polytechnical University Xi'an China

ISBN: (纸本)9798350345759

Aiming at the high reliability design problem of electromagnetic launch control system, this paper proposes a control system design method based on ARM and FPGA architecture. The overall structure of the control system is divided into three parts: box control, subsystem control and module control. Among them, the subsystem controller is composed of a control motherboard and a pulse power management board. The control motherboard is designed based on the architecture of ARM and FPGA. ARM runs logic related processing, and FPGA processes timing control, synchronous feedback and other functions that require high time accuracy. Based on the host computer software, the current curves of specific discharge energy and discharge time sequence are analyzed. The verification results show that the discharge current waveform can be controlled by controlling the discharge sequence of Pulse Forming Network (PFN) through the control system. Under the condition of long equal interval discharge sequence, the peak current decreases and the wave pattern changes gently. The electromagnetic launch control system realized in this paper has high scalability, can monitor more than twenty pulse power units, and can achieve highly reliable control of the launch system based on single shot and continuous shot operation mode. © 2022 IEEE.

关键词： Control systems

来源：评论

学校读者我要写书评

暂无评论

Numerical Study on the Impact Characteristics of a Single Molten Lead Bismuth Droplet on Water

SSRN

引用

SSRN 2024年

作者： Lin, Yue Zhang, Dalin Chen, Yutong Zhang, Xisi Deng, Jian Du, Peng Tian, Wenxi Qiu, Suizheng Su, Guanghui Department of Nuclear Science and Technology State Key Lab. of Multiphase Flow in Power Engineering Shaanxi Key Lab. of Advanced Nuclear Energy and Technology Xi’an Jiaotong University No.28 Xianningxilu Beilinqu Shaanxi Xi’an710049 China Institute of Reactor Engineering Technology China Institute of Atomic Energy Beijing102413 China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Sichuan Chengdu610213 China

As an important link in the possible occurrence of steam explosions, the interaction between molten materials and coolant is of great significance for safety analysis in severe accidents of nuclear reactors. This study is based on the two-dimensional multiphase and multi-component fluid dynamics code ACENA to model the process of single molten lead bismuth droplet impacting a water tank and obtain the velocity changes of the molten droplet as it moves through the water tank. Furthermore, a sensitivity analysis of relevant factors such as the heat transfer area fraction and drag coefficient of the droplet is carried out. To verify models in ACENA, the computation results are compared to experimental data. It is demonstrated that the overall trend of the velocity curve acquired by the ACENA code during the interaction between a molten lead bismuth droplet and water is consistent with the experimental results. The droplet falling velocity increases with the increase in droplet temperature when the temperature of water is the same, and the droplet falling velocity increases with the increase of water temperature at the same droplet temperature. The simulation results by ACENA code for MFCI are in good agreement with experiments which verifies the accuracy of relevant models in ACENA. It can provide an effective means for safety analysis of nuclear reactors in China. © 2024, The Authors. All rights reserved.

关键词： Drops

来源：评论

学校读者我要写书评

暂无评论

CMD: A Cache-assisted GPU Memory Deduplication Architecture

arXiv

引用

arXiv 2024年

作者： Zhao, Wei Feng, Dan Tong, Wei Wei, Xueliang Wu, Bing The Wuhan National Laboratory for Optoelectronics Key Laboratory of Information Storage System Engineering Research Center of Data Storage Systems and Technology Ministry of Education of China School of Computer Science and Technology Huazhong University of Science and Technology China

Massive off-chip accesses in GPUs are the main performance bottleneck, and we divided these accesses into three types: (1) Write, (2) Data-Read, and (3) Read-Only. Besides, We find that many writes are duplicate, and the duplication can be inter-dup and intra-dup. While inter-dup means different memory blocks are identical, and intra-dup means all the 4B elements in a line are the same. In this work, we propose a cache-assisted GPU memory deduplication architecture named CMD to reduce the off-chip accesses via utilizing the data duplication in GPU applications. CMD includes three key design contributions which aim to reduce the three kinds of accesses: (1) A novel GPU memory deduplication architecture that removes the inter-dup and inter-dup lines. As for the inter-dup detection, we reduce the extra read requests caused by the traditional read-verify hash process. Besides, we design several techniques to manage duplicate blocks. (2) We propose a cache-assisted read scheme to reduce the reads to duplicate data. When an L2 cache miss wants to read the duplicate block, if the reference block has been fetched to L2 and it is clean, we can copy it to the L2 missed block without accessing off-chip DRAM. As for the reads to intra-dup data, CMD uses the on-chip metadata cache to get the data. (3) When a cache line is evicted, the clean sectors in the line are invalidated while the dirty sectors are written back. However, most read-only victims are re-referenced from DRAM more than twice. Therefore, we add a full-associate FIFO to accommodate the read-only (it is also clean) victims to reduce the re-reference counts. Experiments show that CMD can decrease the off-chip accesses by 31.01%, reduce the energy by 32.78% and improve performance by 37.79%. Besides, CMD can improve the performance of memory-intensive workloads by 50.18%. © 2024, CC BY-NC-ND.

关键词： Cache memory

来源：评论

学校读者我要写书评

暂无评论

Integration of SSPP Antenna and Vivaldi Arrays for 5G Sub-6 GHz and Millimeter-Wave Applications

引用

IEEE Antennas and Wireless Propagation Letters 2025年

作者： Cheng, Houyuan Li, Shangru Fu, Yang Yang, Helin Wu, Jiong Zhou, Xiangli Shi, Xintong Central China Normal University College of Physical Science and Technology Wuhan430079 China State Key Laboratory of Complex Electromagnetic Environmental Effects on Electronics and Information System National University of Defense Technology China

An integrated antenna system covering 5G Sub-6 GHz and millimeter-wave bands is proposed, combining a spoof surface plasmon polariton (SSPP) antenna and two Vivaldi arrays. The integrated design comprises three radiators: an SSPP array, a linear tapered slot (LTS), and Vivaldi arrays. The SSPP antenna (excited by port 1) operates in the Sub-6 GHz band (SUB: 4–4.9 GHz and 5.3–6 GHz) through its SSPP array, while the LTS covers millimeter-wave band 1 (MMW1: 23–25.8 GHz). Dual Vivaldi arrays, symmetrically distributed on both sides of the antenna and excited by ports 2 and 3, operate in millimeter-wave band 2 (MMW2: 18–25.8 GHz). Measured results demonstrate average realized gains of 11 dBi (SUB), 13 dBi (MMW1), and 14 dBi (MMW2). This design shows potential for 5G communication and radar systems. © 2002-2011 IEEE.

关键词： Millimeter waves

来源：评论

学校读者我要写书评

暂无评论

Multi-Level Robotic Pouring Using Offline Reinforcement Learning

Multi-Level Robotic Pouring Using Offline Reinforcement Lear...

引用

IEEE International Conference on Robotics and Biomimetics

作者： Xiaoxiong Zhang Junwei Liu Wei Zhang Shenzhen Key Laboratory of Control Theory and Intelligent Systems School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen China

ISBN: (数字)9798331509644

ISBN: (纸本)9798331509651

This paper presents a novel learning-based method for a robotic manipulator to achieve liquid pouring across different liquid levels using only visual sensors. Previous works have relied on either online reinforcement learning or imitation learning, which are limited by sim-to-real gaps or data efficiency. In this paper, we propose to combine supervised learning and offline reinforcement learning, utilizing a human demonstration dataset containing only successful pouring at the highest level. Specifically, our approach employs supervised learning for a visual classifier, transforming the visual input into a categorical distribution over liquid levels. The offline reinforcement learning method is applied to a binary-conditioned control policy, which takes a binary signal and the robot's proprioception as inputs to determine the action. The binary signal indicates whether the desired liquid level has been reached based on the target liquid level. Through experiments, our method demonstrates superior effectiveness compared to a state-of-the-art imitation learning algorithm. Moreover, tests in unseen scenarios and multiple liquid level commands verify the generalization and transferability of our approach.

关键词： Visualization Liquids Imitation learning Biomimetics Supervised learning Reinforcement learning Robot sensing systems Manipulators Sensors Robots

来源：评论

学校读者我要写书评

暂无评论

Multi-Agent Reinforcement Learning with Region Division and Leader-Follower Communication

Multi-Agent Reinforcement Learning with Region Division and ...

引用

Chinese Automation Congress (CAC)

作者： Chao Wang Xiang Xu Shenzhen Key Laboratory of Control Theory Intelligent Systems School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen China

ISBN: (数字)9798350368604

ISBN: (纸本)9798350368611

The integration of multi-agent reinforcement learning (MARL) into complex systems has paved new ways for collaborative problem-solving. However, traditional approaches to MARL frequently encounter the challenge of achieving ef-ficient communication among agents, essential for coordinated action. This paper introduces a region division and leader-follower(RDLF) communication algrithm with the MARL frame-work. RDLF divides the environment into several regions, each managed by a leader agent that coordinates the actions of fol-lower agents and handling inter-region communication. This hier-archical structure reduces unnecessary communication, enhancing learning efficiency. Experimental results in multi-particle en-vironments demonstrate RDLF's superiority over existing MARL algorithms, especially with increasing agent numbers. RDLF effectively addresses scalability and communication challenges in large-scale multi-agent systems, providing a robust foundation for its application in complex and dynamic environment.

关键词： Automation Scalability Heuristic algorithms Collaboration Reinforcement learning Problem-solving Complex systems Multi-agent systems

来源：评论

学校读者我要写书评

暂无评论

design and analysis of truss deployable antenna mechanism based on a novel symmetric hexagonal profile division method

引用

Chinese Journal of Aeronautics 2021年第8期34卷 87-100页

作者： Jinwei GUO Yongsheng ZHAO Yundou XU Yongjie LI Jiantao YAO Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan UniversityQinhuangdao 066004China Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of National Education Yanshan UniversityQinhuangdao 066004China

As the deployment,supporting,and stability mechanisms of satellite antennas,space-deployable mechanisms play a key role in the field of *** order to design truss deployable antenna supporting mechanisms with large folding rate,high accuracy,easy deployment and strong stability,aiming at the geometric division of the parabolic reflector,a novel method based on symmetric hexagonal division and its corresponding modular truss deployable antenna mechanism is proposed,and the original method based on asymmetric triangular division and its corresponding mechanisms are presented for comparative ***,the screw theory is employed to analyze the mobility of different ***,the improved three-dimensional mesh method is used to divide the reflector surface of a large parabolic antenna designed by the two different methods,and the profile accuracy and the type of links are taken as the evaluation indexes to quantitatively analyze the division ***,a three-dimensional model of the modular deployable mechanism based on the symmetric hexagonal design is developed,and the deployable mechanisms with different configurations based on the two design methods are compared and analyzed from the mechanical *** research results provide a good theoretical reference for the design of deployable truss antenna mechanisms and their application in the aerospace field.

关键词： Mobility Modular mechanism Profile division Screw theory Truss deployable antenna

来源：评论

学校读者我要写书评

暂无评论

design of low-weight, small-size and high-efficiency equalization circuits based on switched-capacitors 4

Design of low-weight, small-size and high-efficiency equaliz...

引用

2022 4th International Conference on Electronic Engineering and Informatics, EEI 2022

作者： Ding, Yanhong Zhao, Xin Li, Kun Liu, Qing Shi, Gengxin School of Integrated Circuit Science and Engineering Tianjin University of Technology Tianjin China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control Tianjin University of Technology Tianjin China China Electronics Technology Group Corporation Tianjin China

ISBN: (纸本)9783800759231

An any cell to any cell equalization circuit, which is based on switched capacitors and energy bus, is proposed in this paper. In this equalization topology, any high voltage cell can directly transfer the power to any low voltage cell through energy bus. With the increasing miniaturisation and integration of circuit boards, the topology proposed in this paper reduces the size of the circuit by varying the capacitance and frequency in order to further reduce the area and weight of the circuit. At the same time compared with the equalization circuit using transformers or inductance devices, this circuit has the characteristics of low cost, low-weight, small-size, easy integration and simple control scheme and it is suitable for applictions such as aerospace and unmanned aerial vehicles. The feasibility of the circuit topology is verified by formula demonstration and simulation results. © VDE VERLAG GMBH ∙ Berlin ∙ Offenbach.

关键词： Cells

来源：评论

学校读者我要写书评

暂无评论

Carbon Fiber Composite Honeycomb Structures and the Application for Satellite Antenna Reflector with High Precision

引用

Advances in Astronautics science and technology 2022年第4期5卷 423-441页

作者： Wei, Xingyu Wang, Yan Xue, Pengcheng Zhang, Taotao Rouis, Abir Xiao, Wei Xiong, Jian Center for Composite Materials and Structures Harbin Institute of Technology Harbin 150001 China National Key Laboratory of Science and Technology On Advanced Composites in Special Environments Harbin Institute of Technology Harbin 150080 China Beijing Institute of Spacecraft System Engineering Beijing 10000 China

This article summarizes the composite honeycomb structure which possess important meaning and application value on the high-precision satellite antenna reflector. The key technologies of composite material honeycomb structure are summarized, including the material selection for satellite antenna reflector, honeycomb configuration, fabrication process, mechanical properties, lightweight design, surface accuracy, thermal deformation control and other issues. The development goal of “lighter, larger, more refined and more stable” are put forward after looking forward to the manufacturing technology and functional requirement of the future satellite antenna reflector. © 2022, Chinese Society of Astronautics.

关键词： Composite honeycomb material Fabrication method Mechanical property Sandwich structure Satellite antenna reflector

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：