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A stiffness-matching based evaluation approach for compliance of mechanical systems in shield tunneling machines

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Science China(technological Sciences) 2012年第10期55卷 2926-2935页

作者： Zhao Yong WANG hao YU HaiDong LAI XinMin LIN ZhongQin Shanghai Key Laboratory of digital Auto-body engineering Shanghai Jiao Tong UniversityShanghai 200240China State key Laboratory of Mechanical systems and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

As the most important performance,compliance of shield tunneling machines(STM) is defined as the capability to accommodate the sudden change of the load induced by the variable geological conditions during *** to the different requirements of the compliant tasks,the existing methods in the robotic field cannot be utilized in the analysis and design of the mechanical system of shield tunneling *** this paper,based on the stiffness of the mechanical system and the equivalent contact stiffness of the tunnel face,the tunneling interface-matching index(IMI) is proposed to evaluate the compliance of the *** IMI is defined as a metric to describe the coincidence of the stiffness curves of the mechanical system and the tunnel ***,a tunneling case is investigated in the paper as an example to expound the validation of IMI and the analytical *** conclusion,the IMI presented here can be served as an appraisement of the capability in conforming to the load fluctuation,and give instructions for the design of the thrust system of shield tunneling machines.

关键词： shield tunneling machine compliance stiffness matching

Mechanical properties and damage characteristics of solidified body-coal combination in continuous driving and gangue backfilling

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International Journal of Mining Science and Technology 2023年第10期33卷 1217-1228页

作者： Yi Tan hao Cheng Wenbing Guo Erhu Bai Shaopu Zhang Yu Wang Zihao Li School of Energy Science and engineering Henan Polytechnic UniversityJiaozuo 454000China State Collaborative Innovation center of Coal Work Safety and Clean-Efficiency Utilization Henan Polytechnic UniversityJiaozuo 454000China

Recovery of the coal buried under buildings,railways and water bodies and the residual coal in irregularly arranged fully mechanized mining faces is a common engineering problem facing underground coal *** this study,a mining technology of continuous driving and gangue backfilling(CDGB)was *** technology,which can not only alleviate ground subsidence and gangue discharge,but also release the above-mentioned coals,contributes to green and efficient sustainable development of *** stability of the system of the solidified body-reserved coal pillar combination(S-C combination)is crucial to the CDGB ***,it is of great significance to explore the mechanical and damage characteristics of S-C combination in the synergistic bearing ***,four sets of differentshaped S-C combination specimens were fabricated and a S-C combination bearing structure in CDGB was constructed to explore the differences in mechanical characteristics and damage modes of different-shaped S-C combination specimens during ***,their surface strain field evolutions and acoustic emission(AE)response characteristics in the load-bearing process were obtained with the aid of the {2. image correlation technique and the AE signal monitoring ***,a damage evolution model based on AE parameters and mechanical parameters was established to clarify the damage evolution *** following results were obtained:(1)The free area of S-C combination can serve as a quantitative index to evaluate the stability of the overburden control system;(2.The concept of critical value k of the free area was first *** the free area exceeds the critical value k(free area ratio greater than 1.13),the deformation resistance and the free area changes becomes negatively correlated;(3)As the free area expands,the failure of the S-C combination specimen evolves from tensile failure to shear *** distribution characteristics of the axial strain f

关键词： Continuous driving and gangue backfilling Solidified body-coal combination Mechanical properties Damage characteristics digital image correlation technology Acoustic emission

Construction of Human digital Twin Model Based on Multimodal Data and Its Application in Locomotion Mode Identifcation

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Chinese Journal of Mechanical engineering 2023年第5期36卷 7-19页

作者： Ruirui Zhong Bingtao Hu Yixiong Feng hao Zheng Zhaoxi Hong Shanhe Lou Jianrong Tan State Key Laboratory of Fluid Power and Mechatronic systems Zhejiang UniversityHangzhou 310027China engineering research {2. for Design engineering and digital Twin of Zhejiang Province Hangzhou 310027China Hangzhou Innovation Institute Beihang UniversityHangzhou 310052China School of Mechanical and Aerospace engineering Nanyang Technological UniversitySingapore 637460Singapore

With the increasing attention to the state and role of people in intelligent manufacturing, there is a strong demand for human-cyber-physical systems (HCPS) that focus on human-robot interaction. The existing intelligent manufacturing system cannot satisfy efcient human-robot collaborative work. However, unlike machines equipped with sensors, human characteristic information is difcult to be perceived and digitized instantly. In view of the high complexity and uncertainty of the human body, this paper proposes a framework for building a human {2. twin (HDT) model based on multimodal data and expounds on the key technologies. Data acquisition system is built to dynamically acquire and update the body state data and physiological data of the human body and realize the {2. expression of multi-source heterogeneous human body information. A bidirectional long short-term memory and convolutional neural network (BiLSTM-CNN) based network is devised to fuse multimodal human data and extract the spatiotemporal features, and the human locomotion mode identifcation is taken as an application case. A series of optimization experiments are carried out to improve the performance of the proposed BiLSTM-CNN-based network model. The proposed model is compared with traditional locomotion mode identifcation models. The experimental results proved the superiority of the HDT framework for human locomotion mode identifcation.

关键词： Human digital twin Human-cyber-physical system Bidirectional long short-term memory Convolutional neural network Multimodal data

A virtual service placement approach based on improved quantum genetic algorithm

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Frontiers of Information Technology & Electronic engineering 2016年第7期17卷 661-671页

作者： Gang XIONG Yu-xiang HU Le TIAN Ju-long LAN Jun-fei LI Qiao ZHOU national digital Switching {2. engineering&technological research center Zhengzhou 450002China Department of Mathematics and Computer Science University of AntwerpAntwerp 2020Belgium

Despite the critical role that middleboxes play in introducing new network functionality,management and innovation of them are still severe challenges for network operators,since traditional middleboxes based on hardware lack service flexibility and ***,though new networking technologies,such as network function virtualization(NFV) and softwaredefined networking(SDN),are considered as very promising drivers to design cost-efficient middlebox service architectures,how to guarantee transmission efficiency has drawn little attention under the condition of adding virtual service process for ***,we focus on the service deployment problem to reduce the transport delay in the network with a combination of NFV and ***,a framework is designed for service placement decision,and an integer linear programming model is proposed to resolve the service placement and minimize the network transport *** a heuristic solution is designed based on the improved quantum genetic *** results show that our proposed method can calculate automatically the optimal placement *** scheme can achieve lower overall transport delay for a network compared with other schemes and reduce 30% of the average traffic transport delay compared with the random placement scheme.

关键词： Software-defined networking(SDN) Network function virtualization Quantum genetic algorithm Middlebox

S-Mesh: a Mesh-based on-chip network with separation of control and transmission

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 86-91,102页

作者： LIU hao ZOU Xue-cheng JI Li-xin CAI Meng ZHANG Ke-feng Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China national digital Switching {2. engineering and technological R&D center Zhengzhou 450002 China

The current network-on-chip （NoC） topology cannot predict subsequent switch node status promptly. Switch nodes have to perform various functions such as routing decision, data forwarding, packet buffering, congestion control and properties of an NoC system. Therefore, these make switch architecture far more complex. This article puts forward a separating on-chip network architecture based on Mesh （S-Mesh）, S-Mesh is an on-chip network that separates routing decision flow from the switches. It consists of two types of networks： datapath network （DN） and control network （CN）. The CN establishes data paths for data transferring in DN. Meanwhile, the CN also transfers instructions between different resources. This property makes switch architecture simple, and eliminates conflicts in network interface units between the resource and switch. Compared with 2.-Mesh, Toms Mesh, Fat-tree and Butterfly, the average packet latency in S-Mesh is the shortest when the packet length is more than 53 B. Compared with 2.-Mesh, the areas savings of S-Mesh is about 3%-7/% and the power dissipation is decreased by approximate 2..

关键词： network on-chip Mesh architecture separation system congestion avoidance lower latency

Robust optimal control for anaerobic-anoxic-oxic reactors

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Science China(technological Sciences) 2021年第7期64卷 1485-1499页

作者： HAN HongGui ZHANG JiaCheng DU ShengLi SUN hao Yuan QIAO JunFei Faculty of Information Technology Beijing University of TechnologyBeijing100124China Beijing Key Laboratory of Computational Intelligence and Intelligent system Beijing100124China engineering research {2. of digital Community Ministry of EducationBeijing100124China

Anaerobic-anoxic-oxic(A_2.) reactors, as the core parts of wastewater treatment process(WWTP), have attracted considerable attention to achieve the reliability of denitrification and dephosphorization. However, it is difficult to realize the optimal operation of A_2. reactors due to the existence of nonlinear dynamics and large uncertainties. To solve this problem, a robust optimal control(ROC) strategy is developed to improve the operation performance of A_2. reactors. First, data-driven systematic evaluation criteria are developed to describe the operational indicators of changeable conditions. Second, a robust optimization algorithm is designed to select the optimal solution. Third, a fuzzy neural network(FNN) is used to track the optimal solution in the control process. Finally, this proposed ROC strategy is applied to the phosphorus removal benchmark simulation model(BSM1-P) and the real A_2. reactors. The results demonstrate that the strategy developed in this paper has great potential for application in real A_2. reactors.

关键词： anaerobic-anoxic-oxic reactors robust optimal control robust optimization fuzzy neural network

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一种解析与执行联动的SDN可编程数据平面

电子学报 2017年第5期45卷 1103-1108页

作者：孙鹏浩兰巨龙胡宇翔段通国家数字交换系统工程技术研究中心河南郑州450002

当前互联网技术发展迅速,新型网络协议的不断出现,要求网络转发设备能够及时提供对新协议的支持.目前,软件定义网络要兼顾可编程协议解析和数据转发性能仍然面临诸多困难.对此,本文提出了基于解析和执行联动结构的可编程数据平面(CLIPE)... 详细信息

当前互联网技术发展迅速,新型网络协议的不断出现,要求网络转发设备能够及时提供对新协议的支持.目前,软件定义网络要兼顾可编程协议解析和数据转发性能仍然面临诸多困难.对此,本文提出了基于解析和执行联动结构的可编程数据平面(CLIPE),通过在硬件的解析器上部署用户可定义模块,可实时更新硬件中解析逻辑中的协议多叉树,从而实现协议解析的用户定制性;并且,通过解析器和动作执行器联动的创新结构,减少了整个处理架构的冗余性,从而减小动作执行时延,提高了硬件资源利用率,与现有方案相比,节约了11%的逻辑资源和2.%的BRAM资源.最后,本文基于NetFPGA-10G板卡完成了本方案的原型机实现.

关键词：网络数据平面灵活解析动作处理器可编程

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面向全可编程网络数据平面的资源优化方法

电子学报 2018年第10期46卷 2423-2429页

作者：申涓段通兰巨龙国家数字交换系统工程技术研究中心河南郑州450002

现有数据平面无法在整体上支持网络功能的创新和演进,因此面向用户可编程的新型网络数据平面技术发展迅速.针对现有可编程数据平面硬件开销过大且缺乏资源优化的问题,从解析器、匹配表、动作执行器三个方面建立了资源开销模型,并分别提... 详细信息

现有数据平面无法在整体上支持网络功能的创新和演进,因此面向用户可编程的新型网络数据平面技术发展迅速.针对现有可编程数据平面硬件开销过大且缺乏资源优化的问题,从解析器、匹配表、动作执行器三个方面建立了资源开销模型,并分别提出了类型域合并、匹配域偏移量合并、"域-字"拆分合并映射等资源优化方法.基于Net FPGA的仿真结果表明,与现有机制相比,所提方法减小了38%左右的资源开销.

关键词：网络数据平面可编程硬件结构资源优化

Driftor: mitigating cloud-based side-channel attacks by switching and migrating multi-executor virtual machines

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Frontiers of Information Technology & Electronic engineering 2019年第5期20卷 731-748页

作者： Chao YANG yun-fei GUO Hong-chao HU Ya-wen WANG Qing TONG Ling-shu LI national digital Switching {2. engineering & technological research center Zhengzhou 450003 China

Co-residency of different tenants’ virtual machines(VMs) in cloud provides a good chance for side-channel attacks, which results in information leakage. However, most of current defense suffers from the generality or compatibility problem, thus failing in immediate real-world deployment. VM migration, an inherit mechanism of cloud systems, envisions a promising countermeasure, which limits co-residency by moving VMs between servers. Therefore, we first set up a unified practical adversary model, where the attacker focuses on effective side channels. Then we propose Driftor, a new cloud system that contains VMs of a multi-executor structure where only one executor is active to provide service through a proxy, thus reducing possible information leakage. Active state is periodically switched between executors to simulate defensive effect of VM migration. To enhance the defense, real VM migration is enabled at the same time. Instead of solving the migration satisfiability problem with intractable CIRCUIT-SAT, a greedy-like heuristic algorithm is proposed to search for a viable solution by gradually expanding an initial has-to-migrate set of VMs. Experimental results show that Driftor can not only defend against practical fast side-channel attack, but also bring about reasonable impacts on real-world cloud applications.

关键词： Cloud computing Side-channel attack Information leakage Multi-executor structure Virtual machine switch Virtual machine migration