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Preservation of local linearity by neighborhood subspace scaling for solving the pre-image problem

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第4期15卷 254-264页

作者： Sheng-kai yang jian-yi MENG Hai-bin SHEN Institute of VLSI Design Zhejiang University

An important issue involved in kernel methods is the pre-image problem. However, it is an ill-posed problem, as the solution is usually nonexistent or not unique. In contrast to direct methods aimed at minimizing the distance in feature space, indirect methods aimed at constructing approximate equivalent models have shown outstanding performance. In this paper, an indirect method for solving the pre-image problem is proposed. In the proposed algorithm, an inverse mapping process is constructed based on a novel framework that preserves local linearity. In this framework, a local nonlinear transformation is implicitly conducted by neighborhood subspace scaling transformation to preserve the local linearity between feature space and input space. By extending the inverse mapping process to test samples, we can obtain pre-images in input space. The proposed method is non-iterative,and can be used for any kernel functions. Experimental results based on image denoising using kernel principal component analysis(PCA) show that the proposed method outperforms the state-of-the-art methods for solving the pre-image problem.

关键词： Kernel method Pre-image problem Nonlinear denoising Kernel PCA Local linearity preserving

Modifying microstructures and tensile properties of Mg-Sm based alloy via extrusion ratio

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Journal of Magnesium and Alloys 2021年第3期9卷 1098-1109页

作者： kai Guan Rui Ma Jinghuai Zhang Ruizhi Wu Qiang yang jian Meng Key Laboratory of Superlight Material and Surface Technology Ministry of EducationCollege of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001PR China Department of Materials Engineering The University of TokyoTokyo 113-8656Japan State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022PR China

Microstructure and tensile properties of a Mg-Sm-Zn-Zr alloy with various extrusion ratios(ERs)of 6.9,10.4 and 17.6 were systematically *** was identified that,greater ER increased dynamic recrystallization(DRX)fraction and coarsened DRX grains,which further suggests weakened basal fiber texture for the studied *** is mainly due to the rising temperature from massive deformation heat when *** a result,greater ER corresponds to a decreased strength but improved ***,transmission electron microscopy(TEM)observations reveal that the dominant intermetallic phase,Mg_(3)Sm,is metastable,and it will transform into Mg_(41)Sm_(5)during extrusion with *** transformation leads to the accumulation of surplus Sm and Zn atoms,which induces the precipitation of Sm Zn_(3)phase at the surface of Mg_(41)Sm_(5)matrix.

关键词： Magnesium alloys Extrusion ratio Microstructure Phase transition Transmission electron microscopy Tensile properties

Distribution optimization of circulating water in air-cooled heat exchangers for a typical indirect dry cooling system on the basis of entransy dissipation

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Science China(Technological Sciences) 2015年第4期58卷 617-629页

作者： SUN jian YUAN kai yang Li Jun CHEN Lin DU Xiao Ze yang Yong Ping Key Laboratory of Condition Monitoring and Control for Power Plant Equipments of Ministry of Education School of Energy Power and Mechanical Engineering North China Electric Power University

The flow and heat transfer of air-cooled heat exchangers play important roles in the performance of indirect dry cooling systems in power plants,so it is of benefit to the design and operation of a typical indirect dry cooling system to optimize the thermo-flow characteristics of air-cooled heat *** entransy dissipation method is applied to the performance optimization of air-cooled heat exchangers in this *** irreversible heat transfer processes in air-cooled heat exchangers,the heat transfer between circulating water and cooling air and the mixing of circulating water,are taken into account and analyzed by means of the entransy dissipation *** total entransy dissipation rate,which connects the geometrical parameters of air-cooled heat exchanger sectors and the heat capacity rates of the fluids to the heat flow rate in every sector,is *** on the mathematical relation and the conditional extremum method,an optimization equation group is derived,by which the air-cooled heat exchanger with known air-side parameters is optimized,showing that the entransy dissipation based optimization approach can contribute to the distribution optimization of circulating water in air-cooled heat exchangers of a typical indirect dry cooling system.

关键词： indirect dry cooling system air-cooled heat exchanger entransy dissipation optimization

PCB CT Image Element Segmentation Model Optimizing the Semantic Perception of Connectivity Relationship

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Computers, Materials & Continua 2024年第11期81卷 2629-2642页

作者： Chen Chen kai Qiao Jie yang jian Chen Bin Yan School of Information Systems Engineering PLA Strategy Support Force Information Engineering UniversityZhengzhou450001China

Computed Tomography(CT)is a commonly used technology in Printed Circuit Boards(PCB)non-destructive testing,and element segmentation of CT images is a key subsequent *** the development of deep learning,researchers began to exploit the“pre-training and fine-tuning”training process for multi-element segmentation,reducing the time spent on manual ***,the existing element segmentation model only focuses on the overall accuracy at the pixel level,ignoring whether the element connectivity relationship can be correctly *** this end,this paper proposes a PCB CT image element segmentation model optimizing the semantic perception of connectivity relationship(OSPC-seg).The overall training process adopts a“pre-training and fine-tuning”training process.A loss function that optimizes the semantic perception of circuit connectivity relationship(OSPC Loss)is designed from the aspect of alleviating the class imbalance problem and improving the correct connectivity ***,the correct connectivity rate index(CCR)is proposed to evaluate the model’s connectivity relationship recognition *** show that mIoU and CCR of OSPC-seg on our datasets are 90.1%and 97.0%,improved by 1.5%and 1.6%respectively compared with the baseline *** visualization results,it can be seen that the segmentation performance of connection positions is significantly improved,which also demonstrates the effectiveness of OSPC-seg.

关键词： Semantic segmentation PCB non-destructive testing mask image modeling connectivity relationship

Rh-Catalyzed diastereoselective addition of arylboronic acids to α-keto N-tert-butanesulfinyl aldimines: synthesis of α-amino ketones

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Organic Chemistry Frontiers 2022年第4期9卷 1016-1022页

作者： Cece Wang Lu Zhou jian Qiu kai yang Qiuling Song Key Laboratory of Molecule Synthesis and Function Discovery Fujian Province UniversityCollege of Chemistry at Fuzhou UniversityFuzhouFujian350108China Institute of Next Generation Matter Transformation College of Materials Science Engineering at Huaqiao University668 Jimei BoulevardXiamenFujian361021China

Herein we present a diastereoselective addition of arylboronic acids toα-keto N-tert-butanesulfinyl aldi-mines catalyzed by a Rh(I)*** reaction provides a practical method to obtain valuable chiralα-amino ketones with excellent diastereoselectivity,featuring operational simplicity,mild reaction con-ditions and a broad substrate scope.

关键词： catalyst boron stereoselective

Digital twin-based sustainable intelligent manufacturing: a review

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Advances in Manufacturing 2021年第1期9卷 1-21页

作者： Bin He kai-jian Bai Shanghai Key Laboratory of Intelligent Manufacturing and Robotics School of Mechatronic Engineering and AutomationShanghai UniversityShanghai 200444People's Republic of China

As the next-generation manufacturing system,intelligent manufacturing enables better quality,higher productivity,lower cost,and increased manufacturing *** concept of sustainability is receiving increasing attention,and sustainable manufacturing is *** digital twin is an emerging technology used in intelligent manufacturing that can grasp the state of intelligent manufacturing systems in real-time and predict system *** intelligent manufacturing based on a digital twin has advantages in practical *** fully understand the intelligent manufacturing that provides the digital twin,this study reviews both technologies and discusses the sustainability of intelligent ***,the relevant content of intelligent manufacturing,including intelligent manufacturing equipment,systems,and services,is *** addition,thesustainability of intelligent manufacturing is ***,a digital twin and its application are introduced along with the development of intelligent manufacturing based on the digital twin ***,combined with the current status,the future development direction of intelligent manufacturing is presented.

关键词： Intelligent manufacturing Digital twin Advanced manufacturing Industry 4.0 Sustainable manufacturing

Construction of cough refl ex intensity score for critically ill patients based on the Delphi method

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World Journal of Emergency Medicine 2023年第3期14卷 235-237页

作者： Yong-kai Li yang Liu Wen-bin Jia jian-zhong yang Jun Xu Emergency Trauma Center the First Affi liated Hospital of Xinjiang Medical UniversityUrumqi 830000China Emergency Department State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Clinical Medical College&Affi liated Hospital of Chengdu University Chengdu 610000China

Airway management is important for critically ill *** airway management can directly threaten the life of patients.[1]Early correct airway assessment and effective airway management can improve patient prognosis.[2]Coughing ability plays an important role in the decision-making process of airway *** with impaired coughing ability have a higher risk of tracheal intubation during *** concept of cough strength was first proposed by Khamiees in 2001,[3]but the evaluation criteria did not include coughing *** purpose of this study was to assess patients’coughing ability through the Delphi method and expert consultation,to provide data support for establishing a cough reflex intensity score and to construct an advanced airway management model for quick and eff ective evaluation.[4,5]

关键词： patients impaired critically

A Novel Ephemeris Model for Martian Moons Incorporating Their Free Rotation

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Research in Astronomy and Astrophysics 2024年第11期24卷 181-191页

作者： Yong-Zhang yang kai Huang jian-Guo Yan Yu-Qiang Li Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430070China

High-precision ephemerides not only support space missions,but can also be used to study the origin and future of celestial *** this paper,a coupled orbit-rotation dynamics model that fully takes into account the rotation of the Martian moons is *** and Deimos’rotations are first described by Eulerian rotational equations,and integrated simultaneously with the orbital motion *** and orientational parameters of Mars satellites were simultaneously obtained by numerical integration for the first *** order to compare the differences between our newly developed model and the one now used in the ephemerides,we first reproduced and simulated the current model using our own parameters,and then fit it to the Institut de Mécanique Céleste et de Calcul deséphémérides ephemerides using least-square *** adjustment test simulations show Phobos and Deimos’orbital differences between the refined model and the current model are no more than 300 m and125 m,*** orientation parameters are confirmed and the results are in good agreement with the International Astronomical Union ***,we simulated two perturbations(main asteroids and mutual torques)which were not included in our refined model,and find that their effects on the orbits are completely *** for the effect on rotation,we propose to take care of the role of mutual attraction in future models.

关键词： planets and satellites dynamical evolution and stability methods numerical celestial mechanics astrometry

Vapor-liquid Phase Equilibria for CO_2+Tertpentanol Binary System at Elevated Pressures

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Chemical Research in Chinese Universities 2011年第4期27卷 678-682页

作者： WANG Lin LUO jian-cheng yang Hao CHEN kai-xun Chemistry and Pharmaceutical Engineering College Nanyang Normal University Nanyang 473061 P R. China Chemical Engineering College Northwest University Xi ＇an 710069 P. R. China Chemical Engineering College Nanyang Institute of Technology Nanyang 473004 P. R. China

Vapor-liquid phase equilibrium data of tertpentanol in carbon dioxide were measured at temperatures of 313.4, 323.4, 333.5 and 343.5 K and in the pressure range of 4.56--11.44 MPa. The phase equilibium apparatus used in the work was a variable-volume high-pressure cell. The experimental data were reasonably correlated with Peng-Robinson equation of state（PR-EOS） together with van der Waals-2 two-parameter mixing rules. Henry＇s Law constants and partial molar volumes of CO2 at infinite dilution were estimated with Krichevsky-Kasarnovsky equa- tion, and Henry＇s Law constants increase with increasing temperature, however, partial molar volumes of CO2 at infinite dilution are negative whose magnitudes decrease with temperature. Partial molar volumes of CO2 and tertpentanol in liquid phase at equilibrium were calculated.

关键词： Carbon dioxide Tertpentanol Phase equilibrium Henry's Law constant Partial molar volume