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Optimization and Mechanical Accuracy Reliability of a New Type of Forging Manipulator

Chinese Journal of Mechanical engineering 2015年第2期28卷 236-248页

作者： CHEN Kang MA Chunxiang ZHENG Maoqi GAO Feng State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Beijing Aerospace Systems Engineering Institute

Researches on forging manipulator have enormous influence on the development of the forging industry and national *** device and lifting mechanism are the core parts of forging manipulator,and have been studied for longer ***,the optimization and mechanical accuracy reliability of them are less *** on General Function（G_F）set and parallel mechanism theory,proper configuration of 10t forging manipulator is selected firstly.A new type of forging manipulator driven by cylinders is *** solved mechanical analysis of manipulator＇s core mechanisms,expressions of force of cylinders are carried *** order to achieve smaller force afforded by cylinders and better mechanical characteristics,some particular sizes of core mechanisms are optimized intuitively through the combined use of the genetic algorithms（GA）and GUI interface in *** with the original mechanisms,optimized clamp saves at least 8 percent efforts and optimized lifting mechanism 20 percent under maximum working ***,considering the existed manufacture error of components,mechanical accuracy reliability of optimized clamp,lifting mechanism and whole manipulator are demonstrated respectively based on fuzzy reliability *** results show that the accuracy reliability of optimized clamp is bigger than 0.991 and that of optimized lifting mechanism is *** the whole manipulator under maximum working condition,that value exceeds 0.986 4,which means that optimized manipulator has high motion accuracy and is reliable.A new intuitive method is created to optimize forging manipulator sizes efficiently and more practical theory is utilized to analyze mechanical accuracy reliability of forging manipulator precisely.

关键词： forging manipulator G_F set configuration optimization mechanical reliability

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Behavior-based cooperative control method for fixed-wing UAV swarm through a virtual tube considering safety constraints

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Chinese Journal of Aeronautics 2025年

作者： Siyi YUE Duo ZHENG Mingjun WEI Zhichen CHU Defu LIN School of Astronautics Engineering Beijing Institute of Technology Beijing 100081 China National Key Laboratory of Complex System Control and Intelligent Agent Cooperation Yungang Street Beijing 100074 China

Unmanned Aerial Vehicle (UAV) swarm collaboration enhances mission effectiveness. However, fixed-wing UAV swarm flights face collaborative safety control problems within a limited airspace in complex environments. Aimed at the cooperative control problem of fixed-wing UAV swarm flights under the airspace constraints of a virtual tube in a complex environment, this paper proposes a behavior-based distributed control method for fixed-wing UAV swarm considering flight safety constraints. Considering the fixed-wing UAV swarm flight problem in complex environment, a virtual tube model based on generator curve is established. The tube keeping, centerline tracking and flight safety behavioral control strategies of the UAV swarm are designed to ensure that the UAV swarm flies along the inside of the virtual tube safety and does not go beyond its boundary. On this basis, a maneuvering decision-making method based on behavioral fusion is proposed to ensure the safe flight of UAV swarm in the restricted airspace. This cooperative control method eliminates the need for respective pre-planned trajectories, reduces communication requirements, and achieves a high level of intelligence. simulation results show that the proposed behavior-based UAV swarm cooperative control method is able to make the fixed-wing UAV swarm, which is faster and unable to hover, fly along the virtual tube airspace under various virtual tube shapes and different swarm sizes, and the spacing between the UAVs is larger than the minimum safe distance during the flight.

关键词： Unmanned aerial vehicles (UAV) UAV swarm Distributed cooperative control Swarm flight safety Behavior-based method Virtual tube airspace

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Modeling the dynamic alignment of business and information systems via the lens of human-centered architecture evolution

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Journal of systems engineering and Electronics 2021年第4期32卷 881-888页

作者： ZHANG Mengmeng YI Shuanghui CHEN Honghui LUO Aimin LIU Junxian ZHANG Xiaoxue Science and Technology on Information Systems Engineering Laboratory National University of Defense TechnologyChangsha 410072China National Key Laboratory for Complex System Simulation Military Academy of SciencesBeijing 100080China

The complexity of business and information systems(IS)alignment is a growing concern for researchers and practitioners *** extant research on alignment architecture fails to consider the human viewpoint,which makes it difficult to embrace emergent *** paper contributes to the extant literature in the following ***,we combine an enterprise architecture(EA)framework with a human viewpoint to address alignment issues in the architecture design phase;second,we describe a dynamic alignment model by developing a humancentered meta-model that explains first-and second-order changes and their effects on alignment *** paper provides better support for the theoretical research and the practical application of dynamic alignment.

关键词： business and information systems(IS)alignment human viewpoint enterprise architecture(EA) meta-model dynamic alignment

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Curvature-property coupling governed heat transfer deterioration in supercritical helically coiled tubes: Mechanistic insights and mitigation strategies via structural parametrization

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International Journal of Thermal Sciences 2025年 215卷

作者： Chang, Fucheng Xin, Jiaxing Wu, Xiaoyi Li, Liwei Li, Huixiong Zhu, Yanlin National Key Lab of Aerospace Power System and Plasma Technology School of Mechanical Engineering Xi'an Jiaotong University Xi'an710049 China China Special Equipment Testing and Research Institute Beijing100029 China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi'an Jiaotong University Xi'an710049 China Shanghai Nuclear Engineering Research & Design Institute Co. Ltd Shanghai200233 China

The unique thermo-hydrodynamic coupling phenomena in the helically coiled tube (HCT) handling supercritical fluids present both opportunities and challenges for next-generation compact heat exchangers. While the pronounced thermophysical property variations near pseudo-critical temperatures (Tpc) and curvature-induced secondary flows synergistically enhance heat transfer coefficient (HTC), their nonlinear coupling mechanisms may unexpectedly provoke severe heat transfer deterioration (HTD). Through systematic numerical investigations, this study reveals that circumferential wall temperature inhomogeneity (CWTI) exhibits an inverted N-shaped evolution, providing valuable insights for thermal homogenization design near Tpc. The secondary flow Reynolds number (Se), quantifying secondary flow intensity, shows a monotonic increase with decreasing coil diameter (Dc) or inner diameter (Di), reaching saturation in high-enthalpy regions. Notably, CWTI demonstrates non-monotonic behavior, achieving minimum values near Tpc before manifesting distinct rebound characteristics near Tpc conditions. Parametric analysis establishes that: (1) Elevating heat flux (q) increases Se, reducing Dc boosts it by 50.3 %, and decreasing Di raises it by 60.0 %. (2) HTD predominantly initiates at the outer wall under high-q conditions, with Dc reduction achieving HTD suppression and 26.9 % enhancement in the local HTC;(3) Reducing the Di results in a reduction of maximum CWTI by 22.5 %–28.6 %, suggesting that structural parametrization effectively mitigates wall temperature non-uniformity, thus suppressing the HTD. While centered on supercritical water, the dimensionless scaling relationships demonstrate extendibility to other media, with the curvature-property coupling mechanism both elucidating fundamental interactions and guiding robust heat exchanger design. © 2025 Elsevier Masson SAS

关键词： Electric heating

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Semantic segmentation of track image based on deep neural network

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The Journal of China Universities of Posts and Telecommunications 2020年第5期27卷 23-33页

作者： Wang Zhaoying Zhou Junhua Liao Zhonghua Zhai Xiang Zhang Lianping School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Complex Product Advanced Manufacturing Kngineering Research Center Beijing Simulation CenterBeijing 100854China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System EngineeringBeijing 100854China Alibaba Cloud Computing Beijing 100020China

In this paper,deep learning technology was utilited to solve the railway track recognition in intrusion detection *** railway track recognition can be viewed as semantic segmentation task which extends image processing to pixel level *** encoder-decoder architecture DeepLabv3+model was applied in this work due to its good performance in semantic segmentation *** images of the railway track collected from the video surveillance of the train cab were used as experiment dataset in this work,the following improvements were made to the *** first aspect deals with over-fitting problem due to the limited amount of training *** augmentation and transfer learning are applied consequently to rich the diversity of data and enhance model robustness during the training ***,different gradient descent methods are compared to obtain the optimal optimizer for training model *** third problem relates to data sample imbalance,cross entropy(CE)loss is replaced by focal loss(FL)to address the issue of serious imbalance between positive and negative *** of the improved DeepLabv3+model with above solutions is demonstrated by experiment results with different system parameters.

关键词： railway track recognition convolutional neural networks semantic segmentation DeepLabv3+

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Research on information capability based high-performance information sharing in the simulation grid

Research on information capability based high-performance in...

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2010 International Conference on Computer Modeling and simulation, ICCMS 2010

作者： Zhang, Ying-Chao Zhang, Jing Chen, Xin Yu, Qin-Zhang Zhang, Hao Beijing Institute of System Engineering National Key Laboratory of Science and Technology on Complex Systems Simulation Beijing China

ISBN: (纸本)9780769539416

For the purpose of achieving high-performance information sharing in the simulation grid, an information capability-based Three Phase High-performance Information Sharing Approach (TPHPISA for short) is advanced. The main idea of TPHPISA is selecting those information sources with highest information capability and executing the best query plan. To illustrate how TPHPISA works, an application example of implementing high-performance information sharing in the stock market simulation grid is thoroughly analyzed. At last, the searching efficiency and accuracy of TPHPISA are demonstrated through comparing with other similar method. © 2010 IEEE.

关键词： Information analysis

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Flexible peak shaving in coal-fired power plants: A comprehensive review of current challenges, recent advances, and future perspectives

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Energy 2025年 327卷

作者： Wu, Chunlei Wang, Chao Hou, Zongyu Wang, Zhe State Key Laboratory of Power System Operation and Control Tsinghua-Rio Tinto Joint Research Centre for Resources Energy and Sustainable Development International Joint Laboratory on Low Carbon Clean Energy Innovation Institute for Carbon Neutrality Department of Energy and Power Engineering Tsinghua University Beijing100084 China Shanxi Research Institute for Clean Energy Tsinghua University Shanxi 030032 China

Grid stability amidst the global energy transition and the pursuit of carbon neutrality is critically dependent on enhancing the flexible peak-shaving capability of Coal-Fired Power Plants (CFPPs). This review highlights recent advances in improving CFPP flexibility and identifies key challenges, including equipment limitations, inadequate control adaptability, and escalating environmental and economic pressures. These factors contribute to operational instability, reduced efficiency, and increased emissions during rapid and deep load fluctuations. Hybrid modeling approaches, achieving high prediction accuracy across full operational processes and broad load ranges with an average error of 0.79 %, support precise peak shaving optimization. Technologies such as low-load stable combustion, heat-power decoupling, and energy storage integration have facilitated minimum loads of approximately 15 %, while advanced intelligent control systems, in coordination with energy storage, significantly accelerate response times, enabling rapid responses within seconds to minutes. Despite these advancements, challenges remain in system coordination, equipment dynamics, and investment feasibility. Future efforts should focus on the development of digital twin frameworks, multi-scale optimization techniques, and integrated techno-economic strategies to propel CFPPs toward cleaner, smarter, and more resilient operations. © 2025 Elsevier Ltd

关键词： Virtual storage

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Explicit solvent molecular dynamics simulations of chaperonin-assisted rhodanese folding

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Particuology 2009年第3期7卷 220-224页

作者： Ying Ren Jian Gao Ji XU Wei Ge Jinghai Li State Key Laboratory of Multiphase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

Chaperonins are known to facilitate the productive folding of numerous misfolded proteins. Despite their established importance, the mechanism of chaperonin-assisted protein folding remains unknown. In the present article, all-atom explicit solvent molecular dynamics （MD） simulations have been performed for the first time on rhodanese folding in a series of cavity-size and cavity-charge chaperonin mutants. A compromise between stability and flexibility of chaperonin structure during the substrate folding has been observed and the key factors affecting this dynamic process are discussed.

关键词： Molecular dynamics simulation Explicit solvent Chaperonin-assisted Protein folding Molecular chaperonin Rhodanese

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Effect of acidic surface functional groups on Cr(Ⅵ) removal by activated carbon from aqueous solution

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Rare Metals 2010年第3期29卷 333-338页

作者： ZHOU Hualei CHEN Yunfa School of Applied Sciences University of Science and Technology Beijing Beijing 100083 China State Key Laboratory of Multi-phase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

The activated carbon with high surface area was prepared by KOH *** was further modified by H2SO4 and HNO3 to introduce more surface functional *** pore structure of the activated carbons before and after modification was analyzed based on the nitrogen adsorption *** morphology of those activated carbons was characterized using scanning electronic microscopy （SEM）.The surface functional groups were determined by Fourier transform infrared spectroscopy （FTIR）.The quantity of those groups was measured by the Boehm titration ***（VI） removal by the activated carbons from aqueous solution was investigated at different pH *** results show that compared with H2SO4,HNO3 destructs the original pore of the activated carbon more seriously and induces more acidic surface functional groups on the activated *** pH value of the solution plays a key role in the Cr（VI） *** ability of reducing Cr（VI） to Cr（III） by the activated carbons is relative to the acidic surface functional *** higher pH values,the Cr（VI） removal ratio is improved by increasing the acidic surface functional groups of the activated *** lower pH values,however,the acidic surface functional groups almost have no effect on the Cr（VI） removal by the activated carbon from aqueous solution.

关键词： activated carbon surface functional groups removal modification chromium（VI）

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Research on multi-agent based C4ISR effectiveness simulation and evaluation

Research on multi-agent based C4ISR effectiveness simulation...

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2010 International Conference on Computer Modeling and simulation, ICCMS 2010

作者： Zhang, Ying-Chao Feng, Ye Yu, Qin-Zhang Xin, Chen Beijing Institute of System Engineering National Key Laboratory of Science and Technology on Complex Systems Simulation Beijing China

ISBN: (纸本)9780769539416

The effectiveness evaluation of C4ISR is playing a more and more important role in its designing, developing and using. According to its characters, such as complexity and intelligence, the traditional evaluation methods and systems are not feasible and effective enough. In this paper, a multiagent based simulation and evaluation framework of C4ISR is advanced, which includes the architecture and the working procedure. The agent-based simulation model of C4ISR is put forward, according to which the C2 Agent, Armament Agent and the Evaluation Agent are founded. The interaction model between each agent is also designed. At final, based on the Swarm, a multi-agent based C4ISR effectiveness simulation and evaluation prototype is developed, through which NATO C2 effectiveness evaluation is thoroughly analyzed. © 2010 IEEE.

关键词： Multi agent systems

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