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改善机械故障监测和维护的人工智能方法

价值工程 2025年第1期44卷 154-156页

作者：康晨祺青岛城市学院青岛251600

工业4.0时代,传统维护方式难以满足机械故障监测的高效、精准需求。本研究针对预测性维护(PdM),利用工业物联网(IIoT)技术自动采集数据。构建人工神经网络(ANN)模型,分析S型激活函数,采用均方误差(MSE)等评估性能。针对数据不均衡,结合... 详细信息

工业4.0时代,传统维护方式难以满足机械故障监测的高效、精准需求。本研究针对预测性维护(PdM),利用工业物联网(IIoT)技术自动采集数据。构建人工神经网络(ANN)模型,分析S型激活函数,采用均方误差(MSE)等评估性能。针对数据不均衡,结合专家知识分析。实验显示,ANN模型准确度87%,提升维护效率与准确性。PdM策略优势显著,为制造业提供高效、低成本维护方案,奠定科学评估基础,有望推动机械故障监测与维护领域进步。

关键词：故障诊断人工智能机械维护质量控制预测

Electro-optic and Photorefractive Properties of Doped Poly (N-Vinylcarbazole)

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Chinese Physics Letters 1997年第6期14卷 474-477页

作者： WANG Shu-feng HUANG zhi-wen chen zhi-jian GONG qi-huang ZHANG zhi-jie chen Hui-ying Department of Physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871 Department of Chemistry Peking UniversityBeijing 100871

In this work,100μm-thick doped poly(N-vinylcarbazole)films with different contents of the electro-optic(EO)chromophore 2,5-dimethyl-4-(p-nitrophenylazo)anisole and plasticizer N-ethylcarbazole were prepared and sandwiched between two indium-tin oxide-covered glass *** EO measurements and two-beam-coupling experiments were performed by using a single mode(TEM00)He-Ne *** the EO coefficient and the gain for two-beam-coupling were found to be strongly depending on the content of plasticizer.

关键词： Photorefractive coupling beam

Anodized metal oxide nanostructures for photoelectrochemical water splitting

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 584-601页

作者： Ying-zhi chen Dong-jian Jiang Zheng-qi Gong Jing-yuan Li Lu-ning Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Photoelectrochemical(PEC) water splitting offers the capability of harvesting, storing, and converting solar energy into clean and sustainable hydrogen energy. Metal oxides are appealing photoelectrode materials because of their easy manufacturing and relatively high stability. In particular, metal oxides prepared by electrochemical anodization are typical of ordered nanostructures, which are beneficial for light harvesting, charge transfer and transport, and the adsorption and desorption of reactive species due to their high specific surface area and rich channels. However, bare anodic oxides still suffer from low charge separation and sunlight absorption efficiencies. Accordingly, many strategies of modifying anodic oxides have been explored and investigated. In this review, we attempt to summarize the recent advances in the rational design and modifications of these oxides from processes before, during, and after anodization. Rational design strategies are thoroughly addressed for each part with an aim to boost overall PEC performance. The ongoing efforts and challenges for future development of practical PEC electrodes are also presented.

关键词： photoelectrochemical water splitting photoelectrode metal oxide anodization nanostructure structural engineering

Hypercrosslinking Polymers Fabricated from Divinyl Benzene via Friedel-Crafts Addition Polymerization

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Chinese Journal of Polymer Science 2022年第3期40卷 310-320,I0008页

作者： Zheng-Yu Duan Yan-Yan Wang qi-Wei Pan Yun-Feng Xie zhi-Yong chen Shandong Provincial Key Laboratory of Fluorine Chemistry and Chemical Materials School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China Nutrition&Health Research Institute COFCO CorporationBeijing Key Laboratory of Nutrition&Health and Food SafetyBeijing 102209China

Microporous organic polymers with high surface area are widely used in many *** them,hypercrosslinked polymers have been extensively concerned because of their simple processes and low-cost ***,due to most state-of-the-art strategies for HCPs based on condensation reactions,the release of small molecules such as hydrochloric acid and methanol involved in such strategies brings about new hazards to ***,we propose a method of fabrication of hypercrosslinked polymers via self-addition polymerization of divinyl benzene and its crosslinking with polar aromatic *** hypercrosslinked polyDVB-based products are demonstrated by FriedelCrafts addition reaction of double bonds on DVB that can connect adjacent phenyl rings of aromatic molecules to form the crosslinked *** HCPDVB-CB obtained in 1-chlorobutane as solvent has a high micropore content and displays high surface area up to 931 m^(2)/*** this finding,DVB is used as a novel external crosslinker for knitting polar aromatic *** L-phenylalanine and bisphenol A are used as the aromatic units,the obtained HCP(Phe-DVB)and HCP(BPA-DVB)could reach surface area of 612 and 471 m^(2)/g,and have hydrogen uptake of0.62 wt%and 0.58 wt%at 77 K and 1.13 bar by comparison with HCPDVB-CB having hydrogen uptake of 0.30 wt%,respectively.

关键词： Hypercrosslinked polymers Divinyl benzene Friedel-Crafts alkylation Microporous organic polymers Gas storage

Ligustrazine inhibits high voltage-gated Ca^(2+) and TTX-resistant Na^+ channels of primary sensory neuron and thermal nociception in the rat:a study on peripheral mechanism

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Neuroscience Bulletin 2006年第2期22卷 79-84页

作者： Bi-Hua BIE Yong chen zhi-qi ZHAO Institute of Shanghai Physiology Chinese Academy of Sciences Shanghai 200031 China Institute of Neurobiology Fu-Dan University Shanghai 200433 China

Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinociceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency （PWL） to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion （DRG） neurons. Results Intraplantar injection of ligustrazine （0.5 mg in 25 μl） significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion （DRG） neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin （TTX） -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron .in the rat.

关键词： ligustrazine nociception dorsal root ganglion sodium channel calcium channel

Review on the challenges and strategies in oil and gas industry's transition towards carbon neutrality in China

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Petroleum Science 2023年第6期20卷 3931-3944页

作者： qi Zhang Jiang-Feng Liu zhi-Hui Gao Si-Yuan chen Bo-Yu Liu School of Business Administration China University of Petroleum(Beijing)at KaramayKaramay834000XinjiangChina School of Economics and Management China University of Petroleum(Beijing)Beijing102249China Tianshan Research Institute Karamay834000XinjiangChina School of Economics and Management North China Electric Power UniversityBeijing102206China

In light of carbon-neutral pledge, the oil and gas industry has been facing several critical new challenges in China. The current status and new challenges in terms of market mechanism reform, supply-consumption balance and key technology innovation in China's oil and gas industry are reviewed in the present study, and new strategies and roadmaps are proposed to cope with the challenges. The study found that (i) the oil and gas market faces challenges such as incomplete pricing mechanisms, unclear subject rights, and the lack of recognition and trading of carbon assets. (ii) the trade-off between short-term supply security and long-term low-carbon supply is the most critical issue. (iii) in addition to typical challenges such as immature technology and lack of funding support, the unclear multiple technology coupling development mode also poses problems for the low-carbon transformation of the oil and gas industry. To address these new challenges, comprehensive strategies and roadmaps for China's oil and gas industry towards carbon neutrality are proposed and discussed in the aspects of participating in market transactions, restructuring production and consumption, deploying key technology innovations, and planning enterprise strategies. The present study is expected to provide a blueprint for the future development of China's oil and gas industry towards carbon neutrality.

关键词： China's oil and gas industry Carbon neutrality Challenges and strategies

Influence of the Spudcan Angle on the Ultimate Bearing Capacity of Jack-up Platform

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China Ocean Engineering 2018年第4期32卷 476-481页

作者： ZHANG qi-yi LIU zhi-jie Department of Ocean Engineering College of EngineeringOcean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Qingdao 266100China

Jack-up platforms of the Ocean engineering structures always withstand the vertical gravity loads which are applied to the seabed by spudcan, so it is important to determine the bearing capacity and the penetration depth of the spudcan for its geometry. In fact, it is up to the deformation law and the failure modes of soil surrounding the spudcan which can calculate the ultimate bearing capacity of the spudcan foundation on the soil seabed. By using the finite element analysis software Abaqus, the deformation law of soil around the spudcan is analyzed in detail, and the failure modes of soil surrounding the spudcan foundation are achieved. At the same time, based on the limit equilibrium theory, by use of static permissible slip-line field, the ultimate bearing capacity of the spudcan foundation is analyzed and the lower limit solution is derived theoretically, and the effect of the spudcan angle on the ultimate bearing capacity is investigated. The numerical results are compared with those obtained by the theoretical formulas deduced in this paper. On the basis of the lower limit solutions in this paper, the effect of the spudcan angle on the ultimate bearing capacity is revealed, and a practical bearing capacity formula is given to take the effect of the spudcan angle into consideration.

关键词： spudcan lower limit analysis ultimate bearing capacity failure modes Abaqus

Effect of slag on oxide inclusions in carburized bearing steel during industrial electroslag remelting

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 291-300页

作者： Shi-jian Li Guo-guang cheng zhi-qi Miao Lie chen Xin-yan Jiang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Xining Special Steel Group Co. Ltd.

Industrial experiments with three types of slags were performed to investigate the effect of slag on oxide inclusions during electroslag remelting(ESR) process. G20CrNi2Mo bearing steel was used as the consumable electrode and remelted using a 2400-kg industrial furnace. The results showed that most inclusions in the electrode were low-melting-point CaO-MgO-Al_2O_3. After ESR, all the inclusions in ingots were located outside the liquid region. When the slag consisted of 65.70 wt% CaF_2, 28.58 wt% Al_2O_3, and 4.42 wt% CaO was used, pure Al_2O_3 were the dominant inclusions in ingot, some of which presented a clear trend of agglomeration. When the ingot was remelted by a multi-component slag with 16.83 wt% CaO, a certain amount of sphere CaAl_4O_7 inclusions larger than 5 μm were generated in ingot. The slag with 8.18 wt% CaO exhibited greater capacity to control the inclusion characteristics. Thermodynamic calculations indicated that the total Ca and Mg in ingots were attributed from the relics in electrode and strongly influenced by the slag composition. The formation of ingot inclusions was calculated by FactSage^(TM) 7.0, and the results were basically in accordance with the observed inclusions, indicating that a quasi-thermodynamic equilibrium could be obtained in the metal pool.

关键词： bearing steel electroslag remelting slag inclusions thermodynamics

Synchronization Stability in Weighted Complex Networks with Coupling Delays

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Communications in Theoretical Physics 2009年第4期51卷 684-690页

作者： WANG qing-Yun DUAN zhi-Sheng chen Guan-Rong LU qi-Shao School of Statistics and Mathematics Inner Mongolia Finance and Economics College Huhhot 010051 China State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China Department of Electronic Engineering City University of Hong Kong Hong Kong SAR China School of Science Beijing University of Aeronautics and Astronautics Beijing 100083 China

Realistic networks display not only a complex topological structure, but also a heterogeneous distribution of weights in connection strengths. In addition, the information spreading through a complex network is often associated with time delays due to the finite speed of signal transmission over a distance. Hence, the weighted complex network with coupling delays have meaningful implications in real world, and resultantly gains increasing attention in various fields of science and engineering. Based on the theory of asymptotic stability of linear time-delay systems, synchronization stability of the weighted complex dynamical network with coupling delays is investigated, and simple criteria are obtained for both delay-independent and delay-dependent stabilities of synchronization states. The obtained criteria in this paper encompass the established results in the literature as special cases. Some examples are given to illustrate the theoretical results.

关键词： weighted complex networks coupling delays synchronization stability