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基于数字孪生的云网智能运维技术研究

计算机技术与发展 2024年第5期34卷 24-29页

作者：曾至诚匡立伟武汉邮电科学研究院湖北武汉430073 烽火通信科技股份有限公司湖北武汉430074

云网融合的加速发展,既推动着通信网络数字化和智能化转型升级,也带来了云网运维复杂性不断提高的问题。尽管近年来通过各种智能化技术手段取得了一定进展,使网络管理控制变得更加敏捷和高效,但大规模云网设施仍然面临着运行维护过程中... 详细信息

云网融合的加速发展,既推动着通信网络数字化和智能化转型升级,也带来了云网运维复杂性不断提高的问题。尽管近年来通过各种智能化技术手段取得了一定进展,使网络管理控制变得更加敏捷和高效,但大规模云网设施仍然面临着运行维护过程中效率低、周期长和成本高等挑战。针对上述挑战,该文提出基于数字孪生的自适应探测、双重评估、优化调整三种智能运维的技术,旨在提高云网运维的效率并帮助预测网络异常。在自适应探测技术中,利用数据统计方法构建历史时序数据样本,通过算法选择适应的概率分布,预测故障发生的概率。双重评估技术中,通过对孪生系统和物理系统进行双重评估,验证故障原因并进行故障朔源。优化调整技术中,通过张量分解处理大数据,优化数据样本,并通过机器学习训练样本数据来优化调整智能运维模型。实验验证表明,该技术能够预测网络异常、快速定位故障,并优化调整系统,从而实现智能运维的目标。

关键词：云网融合智能运维数字孪生概率分布数据统计机器学习

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稀有金属元素在硬质合金中的应用研究进展

稀有金属与硬质合金 2024年第1期52卷 69-74页

作者：李春芳谯建春郑启文熊韬曾志诚郭智兴杨天恩成都工业职业技术学院四川成都610213 成都名钨科技有限责任公司四川成都610100 四川大学机械工程学院四川成都610065

综述了国内外对稀有金属元素在硬质合金中的应用研究进展,分析了四类元素稀有难熔金属、稀土、稀贵金属和稀散金属对硬质合金微观组织与性能的影响,并展望了稀有金属元素在硬质合金中的应用前景。

关键词：硬质合金稀有难熔金属稀土稀贵金属稀散金属研究进展应用前景

Applied anatomy for pituitary adenoma resection

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Chinese Medical Journal 2011年第15期124卷 2269-2274页

作者： LIU Liang LIU zhi-xiong LIU Yun-sheng LIU Jing-fang zeng Yu zeng zhi-cheng WANG Miao WANG Hao zeng Chang-ming JIANG Xing-jun HEN Xin YANG Shu-guang Department of Neurosurgery Xiangya Hospital Central South University Changsha Hunan 410008 China Department of-Anatomy and Neurobiology Xiangya School of Medicine Central South University Changsha Hunan 410013 China Department of Neurosurgery People＇s Hospital Ningxiang County Changsha Hunan 410600 China Department of Neurosurgery the Third Hospital Ningxiang County Changsha Hunan 410600 China Department of Neuroscience TCM Hospital of Ningxiang County Changsha Htman 410600 China

Background Pituitary adenomas are common intracranial tumors, with a rising incidence in China. Excision is a mainstay therapy for this disease, and is often carried out via transfr0ntal, transsphenoidal or transpterional approaches. However, few studies have systematically addressed the regional anatomy involved in these microsurgical procedures. The present study attempted to establish some key anatomic measurements relevant to pituitary adenoma resection based on cadaver and computer tomography （CT） image studies. Methods Head specimens from 30 randomly selected formalin-fixed adult cadavers were used for anatomical analysis. Measurements were made on the base of the skull following removal of brain structures above the pituitary gland, and on the mid-sagittal plane of the cranium. Parameters were designed by considering the 3 above-mentioned common microsurgical approaches, and obtained on each head using a sliding caliper. Multi-level CT images from 30 individuals were also used for distance measurements between landmark structures that are relevant to these surgeries. All data were subjected to statistical analysis using the SPSS 11.5 software. Results There was statistically significant difference （P〈0.05） of distance measured on cadavers relative to CT images in 3 sets of measurements related to the transfrontal surgical approach, i.e., distances from the midpoint of superciliary arch superior border to the cranial entrance of internal carotid arteries （ICAs）, the opposite side entrance of ICA and to the genu of ICA. While regional anatomical analyses were carried out according to the transpterional approach, statistically significant difference was also found in 3 sets of distance measurements between cadaver and CT image data, with regard to the distances between the pterion and some landmark structures around the pituitary. Conclusions The present study provides key anatomical and CT image measurements involving the 3 conventionally used surgical approach

关键词： pituitary neoplasms surgical approach applied anatomy

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo cheng Peng zeng Chuan-zhi Zang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Switching,explosion,and chaos of multi-wavelength soliton states in ultrafast fiber lasers

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 82-90页

作者： zhi-zeng Si Yue-Yue Wang Chao-Qing Dai College of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityLin’an 311300China

Because of the complexity and difficulty of realizing a multi-wavelength soliton state,reports on its internal dynamic characteristics are *** this study,the switching and periodic soliton explosion processes of the multi-wavelength soliton state in a negative dispersion passively mode-locked fiber laser are *** generation of the multi-wavelength soliton state undergoes the process of noise,oscillation,and stable mode-locking,and the splitting and annihilation of solitons with different group velocities directly impact the generation and disappearance of three *** and negative dispersion lead to different group velocities of *** presence and displacement of solitons with different group velocities cause soliton collisions,which lead to soliton explosions.A soliton experiences relative phase oscillation,chaos,and oscillation,as well as convergence and separation before and after an *** an increase in parameters related to pump power,single-soliton oscillation,multi-wavelength solitons,and chaos are found in experiments and simulations,proving the relevance and reliability between simulation and experimental *** work promotes the dynamical study of multi-soliton collisions in nonlinear science and the development of chaos theory in multi-comb lasers.

关键词： multi-wavelength fiber laser soliton explosion chaos state switching real-time dynamics

Flexible tuning of multifocal holographic imaging based on electronically controlled metasurfaces

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Photonics Research 2024年第1期12卷 61-69页

作者： OWEN zeng CHENXIA LI BO FANG zhi HONG XUFENG JING Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China Centre for THz Research China Jiliang UniversityHangzhou 310018China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China

Programmable hyper-coded holography has the advantage of being programmable as well as being flexibly *** coded metamaterials with excellent electromagnetic modulation capability and the ability to control the phase to modulate the spatial radiation field through external excitation in the form of switching can be used to realize low-cost digital *** design a 1-bit encoded programmable metasurface,which is electrically connected to control the PIN diode in the switching state and to switch the condition of each metasurface cell between“0”and“1.”Using the designed programmable metasurface,we can randomly encode the cell structure to realize single-focus focusing,multi-focusing,and simple holographic letter *** on the nonlinear holographic model,we employ the Gerchberg-Saxton improvement algorithm to modulate the energy distribution at the focus by adjusting the phase ***,we introduce the Fourier convolution principle to regulate the holographic imaging focus flexibly.

关键词： holographic letter excitation

Design of artificial biomimetic channels with Na^(+)permeation rate and selectivity potentially outperforming the natural sodium channel

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Nano Research 2024年第9期17卷 8638-8646页

作者： zhi Zhu Yan Zhao Chao Chang Shaojian Yan Tingyu Sun Shiyu Gu Yangmei Li Dengsong Zhang Chunlei Wang Xiao cheng zeng School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Innovation Laboratory of Terahertz Biophysics National Innovation Institute of Defense TechnologyBeijing 100071China School of Physics Peking UniversityBeijing 100871China International Joint Laboratory of Catalytic Chemistry College of SciencesShanghai UniversityShanghai 200444China Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China

Artificial ion channels that enable high-efficiency ion transport have important implications in nanofluidics and biomedical applications such as drug ***,we show a simulation-based chemical design of a biomimetic sodium channel that possesses permeation rate and selectivity potentially higher than those of the state-of-the-art natural vertebrate voltage-gated sodium ***,our theoretical findings have undergone empirical testing,aligning well with the Arrhenius law as derived from a diverse range of experimental *** high-efficiency ion transport is achieved by anchoring the carboxylate functional groups within the channel filter.A key chemical guiding principle underlying the ion channel design is that the free-energy barrier for the Na^(+)passage across the channel should be comparable to typical thermal energy at room *** the implementation of the chemical design,we found that the relatively low free-energy barrier can be attributed to the compensation effect of the carboxylate groups to the partially lost oxygen shell of the ion within the ion channel,as well as to the consonant vibration of the ions inside and outside the *** mechanistic understanding brings new insight,at the molecular level,into the high-efficiency ion transport across the designed membrane *** proof of principle achieved from the simulations will stimulate future experimental confirmation and potential applications of the high-performance artificial channels in nanofluidics and in bioinspired iontronics.

关键词： sodium channels anchoring carboxylate functional groups molecular dynamics simulations low free-energy barrier for ion passage thermal kinetic energy

Reduction of dinitrogen to ammonia on doped three-atom clusters Nb_(2)M(M=Sc to Cu & Y to Ag)

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Rare Metals 2024年第8期43卷 3810-3818页

作者： Ran cheng Chao-Nan Cui zhi-Xun Luo Beijing National Laboratory for Molecular Science(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy ***-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active *** a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to Ag) clusters was *** key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic *** d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was *** examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these *** work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.

关键词： Three-atom cluster catalysis Three-criteria strategy Nitrogen fixation Ammonia synthesis Theoretical calculations

Low-Rank Optimal Transport for Robust Domain Adaptation

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1667-1680页

作者： Bingrong Xu Jianhua Yin cheng Lian Yixin Su zhigang zeng IEEE the School of Automation Wuhan University of TechnologyWuhan 430070China Intelligent Transportation Systems Research Center Wuhan University of TechnologyWuhan 430063 Chongqing Research Institute Wuhan University of TechnologyChongqingChina the School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 the Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

When encountering the distribution shift between the source(training) and target(test) domains, domain adaptation attempts to adjust the classifiers to be capable of dealing with different domains. Previous domain adaptation research has achieved a lot of success both in theory and practice under the assumption that all the examples in the source domain are welllabeled and of high quality. However, the methods consistently lose robustness in noisy settings where data from the source domain have corrupted labels or features which is common in reality. Therefore, robust domain adaptation has been introduced to deal with such problems. In this paper, we attempt to solve two interrelated problems with robust domain adaptation:distribution shift across domains and sample noises of the source domain. To disentangle these challenges, an optimal transport approach with low-rank constraints is applied to guide the domain adaptation model training process to avoid noisy information influence. For the domain shift problem, the optimal transport mechanism can learn the joint data representations between the source and target domains using a measurement of discrepancy and preserve the discriminative information. The rank constraint on the transport matrix can help recover the corrupted subspace structures and eliminate the noise to some extent when dealing with corrupted source data. The solution to this relaxed and regularized optimal transport framework is a convex optimization problem that can be solved using the Augmented Lagrange Multiplier method, whose convergence can be mathematically proved. The effectiveness of the proposed method is evaluated through extensive experiments on both synthetic and real-world datasets.

关键词： Domain adaptation low-rank constraint noise corruption optimal transport