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Prediction of lime utilization ratio of dephosphorization in BOF steelmaking based on online sequential extreme learning machine with forgetting mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 508-517页

作者： Runhao Zhang jian Yang han Sun Wenkui Yang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting mechanism(FOS-ELM)are applied in the prediction of the lime utilization ratio of dephosphorization in the basic oxygen furnace steelmaking *** ELM model exhibites the best performance compared with the models of MLR and ***-ELM and FOS-ELM are applied for sequential learning and model *** optimal number of samples in validity term of the FOS-ELM model is determined to be 1500,with the smallest population mean absolute relative error(MARE)value of 0.058226 for the *** variable importance analysis reveals lime weight,initial P content,and hot metal weight as the most important variables for the lime utilization *** lime utilization ratio increases with the decrease in lime weight and the increases in the initial P content and hot metal weight.A prediction system based on FOS-ELM is applied in actual industrial production for one *** hit ratios of the predicted lime utilization ratio in the error ranges of±1%,±3%,and±5%are 61.16%,90.63%,and 94.11%,*** coefficient of determination,MARE,and root mean square error are 0.8670,0.06823,and 1.4265,*** system exhibits desirable performance for applications in actual industrial pro-duction.

关键词： basic oxygen furnace steelmaking machine learning lime utilization ratio dephosphorization online sequential extreme learning machine forgetting mechanism

The Influence of Different Solar System Planetary Ephemerides on Pulsar Timing

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Research in Astronomy and Astrophysics 2024年第8期24卷 85-99页

作者： jian-Peng Dai Wei han Na Wang School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China

Pulsar timing offers a comprehensive avenue for exploring diverse topics in physics and *** solar system planetary ephemeris is crucial for pulsar timing as it provides the positions and velocities of solar system planets including the ***,it is inevitable that inherent inconsistencies exist in these *** between various ephemerides can significantly impact pulsar timing and parameter ***,pulsar timing highly depends on the JPL de ephemeris,for instance,the Pulsar Timing Array data analysis predominantly utilizes *** this study,we examine inconsistencies across various ephemeris series,including JPL de,EPM,and ***,discrepancies emerge particularly between the current ephemeris de436 and the earliest released ephemeris de200,as well as the most recent ephemerides,e.g.,de440,INPOP21A,and *** detailed analysis of the effects of ephemeris on geometric correction procedures for the conversion of measured topocentric times of arrival is presented in this *** researches reveal that variations in the Roemer delays across different ephemerides lead to distinct *** timing residuals and the fact that these discrepancies can be readily incorporated into the subsequent pulsar parameters,leading to inconsistent fitting estimates,suggest that the influence of errors in the ephemeris on the timing process might currently be underappreciated.

关键词： (stars)pulsars general-Planetary Systems-time-ephemerides

Knowledge enhanced graph inference network based entity-relation extraction and knowledge graph construction for industrial domain

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Frontiers of Engineering Management 2024年第1期11卷 143-158页

作者： Zhulin han jian WANG College of Electronic and Information Engineering Tongji UniversityShanghai 200092China

With the escalating complexity in production scenarios, vast amounts of production information are retained within enterprises in the industrial domain. Probing questions of how to meticulously excavate value from complex document information and establish coherent information links arise. In this work, we present a framework for knowledge graph construction in the industrial domain, predicated on knowledge-enhanced document-level entity and relation extraction. This approach alleviates the shortage of annotated data in the industrial domain and models the interplay of industrial documents. To augment the accuracy of named entity recognition, domain-specific knowledge is incorporated into the initialization of the word embedding matrix within the bidirectional long short-term memory conditional random field (BiLSTM-CRF) framework. For relation extraction, this paper introduces the knowledge-enhanced graph inference (KEGI) network, a pioneering method designed for long paragraphs in the industrial domain. This method discerns intricate interactions among entities by constructing a document graph and innovatively integrates knowledge representation into both node construction and path inference through TransR. On the application stratum, BiLSTM-CRF and KEGI are utilized to craft a knowledge graph from a knowledge representation model and Chinese fault reports for a steel production line, specifically SPOnto and SPFRDoc. The F1 value for entity and relation extraction has been enhanced by 2% to 6%. The quality of the extracted knowledge graph complies with the requirements of real-world production environment applications. The results demonstrate that KEGI can profoundly delve into production reports, extracting a wealth of knowledge and patterns, thereby providing a comprehensive solution for production management.

关键词： knowledge graph construction industrial BiLSTM-CRF document-level relation extraction graph inference

Pd-catalyzed asymmetric carbonyl alkynylation:Synthesis of axial chiral ynones

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Chinese Chemical Letters 2024年第6期35卷 293-297页

作者： Long Jin jian han Dongmei Fang Min Wang jian Liao Natural Products Research Center Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China College of Chemical Engineering Sichuan UniversityChengdu 610065China University of Chinese Academy of Sciences Beijing 100049China

Ynones are important skeletons in bioactive molecules and valuable building blocks for organic synthesis,thus great efforts have been devoted to their ***,introducing prochiral substrates to construct ynones bearing a chiral framework is unrealized to ***,we reported the first example of Pd/SOP-catalyzed asymmetric carbonylative alkynylation via a non-classical carbonylative Sonogashiratype approach(acyl-Pd(Ⅱ)species generated from nucleophiles).By using cyclic diaryliodonium salts as prochiral substrates,various axial chiral ynones with good functional group tolerance(39 examples),satisfied yields(71%-96%)and excellent enantioselectivities(generally 94%-99%ee)were *** of bioactive compounds,scale-up experiment and useful transformations were also conducted to demonstrate the utility of this process.

关键词： Pd-catalyzed Axial chiral ynones Cyclic diaryliodonium High-valent palladium catalyzed Asymmetric carbonyl alkynylation

Optimization Mechanism of Mechanical Properties of Basalt Fiber-Epoxy Resin Composites by Interfacially Enriched Distribution of Nano-Starch Crystals

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 289-296页

作者： Yanpeng Wei Jiale Zhao jian Zhuang Peng Zhang Zhiwu han College of Biological and Agricultural Engineering Jilin UniversityChangchun 130025China Key Laboratory of Bionics Engineering Ministry of EducationJilin UniversityChangchun 130025China Weichai Lovol Heavy Industry Co. LTDWeifang 261031China

Fibre reinforced polymer composites have become a new generation of structural materials due to their unique advantages such as high specific strength,designability,good dimensional stability and ease of large-area monolithic ***,the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has become a central difficulty in the development of basalt fibre-epoxy *** paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals,which are highly yield and ***,in this paper,corn starch nanocrystals(SNC)were prepared by hydrolysis,and were deposited on the surface of basalt fibers by electrostatic *** that,in order to maximize the modification effect of nano-starch crystals on the interface,the basalt fiber-epoxy resin composite samples were prepared by mixing in a pressureless molding *** test results shown that the addition of basalt fibers alone led to a reduction in the strength of the *** of 0.1 wt%SNC on the surface of basalt fibers can make the strength consistent with pure epoxy *** the adsorption amount of SNC reached 0.5 wt%,the tensile strength of the samples was 23.7%higher than that of pure epoxy *** is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin,which distorts the originally smooth interface,leading to increased stress concentration and the development of *** enhances the binding of basalt *** conclusions of this paper can provide an effective,simple,low-cost and non-polluting method of interfacial enhancement modification.

关键词： Basalt fibres Epoxy resin Fibre reinforced composites Starch nanocrystals Eco-friendly

Human-Machine Shared Lateral Control Strategy for Intelligent Vehicles Based on Human Driver Risk Perception Reliability

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Automotive Innovation 2024年第1期7卷 102-120页

作者： Dongjian Song Bing Zhu jian Zhao Jiayi han State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022China

Intelligent vehicle(Ⅳ)technology has developed rapidly in recent ***,achieving fully unmanned driving still presents numerous challenges,which means that human drivers will continue to play a vital role in vehicle operation for the foreseeable ***-machine shared driving,involving cooperation between a human driver and an automated driving system(AVS),has been widely regarded as a necessary stage for the development of *** onⅣdriving safety,this study proposed a human-machine shared lateral control strategy(HSLCS)based on the reliability of driver risk *** HSLCS starts by identifying the effective areas of driver risk perception based on eye *** establishes an anisotropic driving risk field,which serves as the foundation for the AVS to assess risk *** upon the cumulative and diminishing effects of risk perception,the proposed approach leverages the driver's risk perception effective area and converts the risk field into a representation aligned with the driver's ***,it quantifies the reliability of the driver's risk perception by using area-matching ***,based on the driver’s risk perception reliability and dif-ferences in lateral driving operation between the human driver and the AVS,the dynamic distribution of driving authority is achieved through a fuzzy rule-based system,and the human-machine shared lateral control is completed by using model predictive *** HSLCS was tested across various scenarios on a driver-in-the-loop test *** results show that the HSLCS can realize the synergy and complementarity of human and machine intelligence,effectively ensuring the safety ofⅣoperation.

关键词： Intelligent vehicle Human-machine shared driving Risk perception Driving authority distribution

Research on the solid particle erosion wear of pipe steel for hydraulic fracturing based on experiments and numerical simulations

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Petroleum Science 2024年第4期21卷 2779-2792页

作者： Si-Qi Yang jian-Chun Fan Ming-Tao Liu de-Ning Li Jun-Liang Li Li-Hong han jian-Jun Wang Shang-Yu Yang Si-Wei Dai Lai-Bin Zhang State Key Laboratory of Oil and Gas Equipment CNPC Tubular Goods Research Institute Key Laboratory of Oil and Gas Safety and Emergency Technology China University of Petroleum Oil Production Technology Research Institute of Liaohe Oilfield Company Tianjin Gas Storage Branch PetroChina Dagang Oilfield Company Petroleum Production Engineering Research Institute Daqing Oilfield Company

Erosion wear is a common failure mode in the oil and gas industry. In the hydraulic fracturing, the fracturing pipes are not only in high-pressure working environment, but also suffer from the impact of the high-speed solid particles in the fracturing fluid. Beneath such complex conditions, the vulnerable components of the pipe system are prone to perforation or even burst accidents, which has become one of the most serious risks at the fracturing site. Unfortunately, it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing. Therefore, this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations. Firstly, we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material. The effects of impact angle, flow velocity and applied stress on erosion wear were comprehensively considered. Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters, and the evolution process of particle erosion under different impact angles, impact velocities and applied stress was analyzed. By combining the erosion characteristics, the micro-structure of the eroded area, and the micro-mechanics of erosion damage, the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time. Under high-pressure operating conditions, it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased, resulting in more severe erosion wear of fracturing pipes.

关键词： Erosion wear Applied stress Particle impact dynamics Erosion mechanism

Automatic modulation recognition of radiation source signals based on two-dimensional data matrix and improved residual neural network

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defence Technology（防务技术） 2024年第3期33卷 364-373页

作者： Guanghua Yi Xinhong Hao Xiaopeng Yan jian Dai Yangtian Liu Yanwen han Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China BIT Tangshan Research Institute Beijing 100081China

Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive ***,the AMR of radiation source signals at low SNRs still faces a great ***,the AMR method of radiation source signals based on two-dimensional data matrix and improved residual neural network is proposed in this ***,the time series of the radiation source signals are reconstructed into two-dimensional data matrix,which greatly simplifies the signal preprocessing ***,the depthwise convolution and large-size convolutional kernels based residual neural network(DLRNet)is proposed to improve the feature extraction capability of the AMR ***,the model performs feature extraction and classification on the two-dimensional data matrix to obtain the recognition vector that represents the signal modulation *** analysis and simulation results show that the AMR method based on two-dimensional data matrix and improved residual network can significantly improve the accuracy of the AMR *** recognition accuracy of the proposed method maintains a high level greater than 90% even at -14 dB SNR.

关键词： Automatic modulation recognition Radiation source signals Two-dimensional data matrix Residual neural network depthwise convolution

Clinical Manifestations of Adult Langerhans Cell Histiocytosis with Multisystem Involvement Successfully Treated Using Chemotherapy

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International Journal of dermatology and Venereology 2021年第2期4卷 122-124页

作者： Nai-Yu Lin Xu-Hua Tang jian-de han department of dermatology The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong 510080China

Introduction:Langerhans cell histiocytosis(LCH),the most common histiocytic disorder,characterized by the abnormal over production of histiocytes that tend to infiltrate single or multiple organ systems leading to significant tissue *** presentation:We describe a 23-year-old man suffering from central diabetes insipidus,"hemorrhoids",progressive hearing loss and a surge in *** examination revealed lesion involvement of the skin and mucous membranes,including the perianal area,gingiva,and external auditory *** was diagnosed as LCH,who achieved remission following a chemotherapy ***:LCH is common in children,but it is not surprising to see it in *** clinical manifestations of LCH are highly variable and may involve multiple organs and ***,skin involvement is the most obvious symptom,and dermatologists should be familiar with *** is the first-line treatment for multisystem or multifocal single system adult ***:Characteristic features of LCH involving the perianal area was described in this case which helped the dermatologist to make quick *** also emphasize that a global concept should be established confronting with a patient with multiple complaints.

关键词： Langerhans cell histiocytosis histiocytosis adult multisystem involvement chemotherapy