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Journal of Iron and Steel Research International 2023年第9期30卷 1792-1802页

作者： yu-jie liu Shen Wang jie-bin Qi Xiao-qiang Yan School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Department of Mechanical Engineering and Mechanics Lehigh UniversityBethlehemCommonwealth of Pennsylvania 18015USA

Vibration issues of a five-stand tandem cold rolling mill were found in the steel production practice,and the experimental observation and numerical analysis indicated that the vibrations were related to the back-up roll *** results were validated by replacing the back-up roll bearing with the new bearing resulting in 30%decline in vibration *** describing the four-row cylindrical roller bearing and the vertical system of the cold rolling mill including the bearing were ***,the mechanisms of periodic excitation and amplified vibrations of fault-free bearing were explained theoretically,along with the analysis of bifurcation behaviors of the motion states of the roller bearing and rolling mill *** is found that the energy transmitted between vibrations with different frequencies if multiple excitation frequencies in the rolling mill system were close.

关键词： Rolling mill vibration Cold tandem mill Fault-free bearing Vibration amplification Variable stiffness Characteristics

Multi-objective optimization design of airfoil and wing

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Science China(Technological Sciences) 2004年第1期47卷 15-25页

作者： ZHU Ziqiang FU Hongyan yu Rixin liu jie Beijing University of Aeronautics and Astronautics Beijing 100083China Beijing University of Aeronautics and Astronautics Beijing 100083China Beijing University of Aeronautics and Astronautics Beijing 100083China Beijing University of Aeronautics and Astronautics Beijing 100083China

To extend available monoobjective optimization methods to multiobjective and multidisciplinary optimization, the construction of a suitable resultant objective function (in deterministic method-DM) or a fitness function (in genetic algorithm-GA) is important. An objective function combination method (OFCM) of constructing such a function for constrained optimization problems is suggested. How to use both deterministic and genetic algorithms to biobjetive and bidisciplinary optimal design of high performance airfoils and wings is discussed. Numerical results in both 2D (airfoil) and 3D (wing) cases show that the present method can be used to optimaize different kinds of initial airfoils and wings. The performance of optimized shape is improved significantly. The method is successful and effective.

关键词： multiobjective optimization, genetic algorithm, deterministic optimization method.

Poplar catkin:A natural biomaterial for highly specific and efficient enrichment of sialoglycopeptides

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Chinese Chemical Letters 2017年第5期28卷 1018-1026页

作者： Xiao-Dong Wang yu-jie liu Fen-jie Li Zhi-Li Li Department of Biophysics and Structural Biology Institute of Basic Medical SciencesChinese Academy of Medical Sciences&School of Basic MedicinePeking Union Medical CollegeBeijing 100005China

Sialic acids as terminal entities of larger glycans linked to proteins and lipids are involved in multiple different pathological and physiological *** characterisation of sialoglycoconjugates is required to understand their biological ***,a comprehensive sialylation analysis of sialoglycoconjugates has remained *** this study,we employ a natural biomaterial,poplar catkin derived from white poplar tree（Populus tomentosa Carr.）,to develop a novel capturing microtip for selective and efficient enrichment of sialoglycopeptides,without losses of sialic acid residues and water molecules from *** electron microscopy and Fourier-transform infrared spectroscopy analysis,along with Maule and Wiesner staining assays,indicated that the main components on the outer layer of the poplar catkin are syringyl and guaiacyl lignins which play a key role in enriching sialoglycopeptides from complex peptide mixture.

关键词： Sialogycopeptide Poplar catkin Enrichment Natural biomaterial Mass spectrometry

Effects of Nb and V on Microstructural Evolution,Precipitation Behavior and Tensile Properties in Hot-rolled Mo-bearing Steel

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Journal of Iron and Steel Research International 2016年第6期23卷 559-565页

作者： Fu-ming liu Jian-jun WANG yu-jie liu R.D.K.MISRA Chun-ming liu School of Materials Science and Engineering Northeastern University Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education Northeastern University Laboratory for Excellence in Advanced Steel Research Department of Metallurgical and Materials EngineeringUniversity of Texas at El Paso

Microstructural evolution,precipitation behavior,and tensile properties of four experimental Mo-bearing steels were studied to elucidate the effects of Nb and V on microstructural *** results indicated that the microstructure of hot-rolled steels consisted of polygonal ferrite and degenerate pearlite,and the morphology remained same after holding at 600 ℃for *** smallest grain size was obtained in Nb-V-Mo containing steel,followed by Nb-Mo and V-Mo *** was less in the hot-rolled Mo-bearing *** maximum volume fraction of precipitates was obtained in Nb-V-Mo bearing steel,and the Nb-V-Mo complex carbonitrides were highly stable at 600℃.In the Mo-bearing steel,the yield ratio was lowest at room temperature but highest at 600℃,which was attributed to the precipitation of Mo carbides and drag effect of Mo solute on dislocation movement.

关键词： rolled steels Precipitation tensile solute attributed polygonal holding ferrite dislocation

Experimental study on uniaxial time-dependent ratcheting of a polyetherimide polymer

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 804-810页

作者： Dou-xing PAN Guo-zheng KANG Zhi-wu ZHU yu-jie liu School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

The uniaxial ratcheting behavior of a polyetherimide (PEI) polymer 'TECAPEI' was studied using stress-controlled cyclic loading at room temperature, including both cyclic tension-compression with non-zero tensile mean stress and tension- unloading tests. The experimental observations were focused on the time-dependent ratcheting of the PEI polymer revealed in cyclic tests at diverse stress rates and with different peak stress holding times. The results showed that the PEI polymer shows obvious ratcheting deformation; i.e., the ratcheting strain accumulates progressively in the tensile direction during stress- controlled cyclic tests with non-zero mean stress. The ratcheting is highly dependent on the applied mean stress and stress am-plitude, and is also characterized by a strong time-dependency during the cyclic stressing at diverse stress rates and with different peak stress holding times. The time-dependent ratcheting of the PEI polymer is caused mainly by its remarkable viscosity. A comparison of the ratcheting occurring before and beyond the ultimate stress point of the PEI polymer showed that the ratcheting beyond the ultimate stress point is more significant than that occurring before that point.

关键词： Polyetherimide (PEI) polymer Uniaxial ratcheting Time-dependence Cyclic loading Viscosity

A bi-population immune algorithm for weapon transportation support scheduling problem with pickup and delivery on aircraft carrier deck

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Defence Technology（防务技术） 2023年第4期22卷 119-134页

作者： Fang Guo Wei Han Xi-chao Su yu-jie liu Rong-wei Cui Naval Aviation University No.188Ermalu RoadZhifu DistrictYantai264001Shandong ProvinceChina

The weapon transportation support scheduling problem on aircraft carrier deck is the key to restricting the sortie rate and combat capability of carrier-based *** paper studies the problem and presents a novel solution *** the interference of the carrier-based aircraft deck layout on the weapon transportation route and precedence constraint into consideration,a mixed integer formulation is established to minimize the total objective,which is constituted of makespan,load variance and accumulative transfer time of support *** approach is developed for the ***,based on modeling the carrier aircraft parked on deck as convex obstacles,the path library of weapon transportation is constructed through visibility graph and Warshall-Floyd *** then propose a bi-population immune algorithm in which a population-based forward/backward scheduling technique,local search schemes and a chaotic catastrophe operator are ***,the randomkey solution representation and serial scheduling generation scheme are adopted to conveniently obtain a better *** Taguchi method is additionally employed to determine key parameters of the ***,on a set of generated realistic instances,we demonstrate that the proposed algorithm outperforms all compared algorithms designed for similar optimization problems and can significantly improve the efficiency,and that the established model and the bi-population immune algorithm can effectively respond to the weapon support requirements of carrier-based aircraft under different sortie missions.

关键词： Carrier-based aircraft Weapon transportation support scheduling Pickup and delivery Bi-population immune algorithm

Learn Robust Pedestrian Representation Within Minimal Modality Discrepancy for Visible-Infrared Person Re-Identification

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Journal of Computer Science & Technology 2022年第3期37卷 641-651页

作者： yu-jie liu Wen-Bin Shao Xiao-Rui Sun College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China

Visible-infrared person re-identification has attracted extensive attention from the community due to its potential great application prospects in video *** are huge modality discrepancies between visible and infrared images caused by different imaging *** studies alleviate modality discrepancies by aligning modality distribution or extracting modality-shared features on the original ***,they ignore a key solution,i.e.,converting visible images to gray images directly,which is efficient and effective to reduce modality *** this paper,we transform the cross-modality person re-identification task from visible-infrared images to gray-infrared images,which is named as the minimal modality *** addition,we propose a pyramid feature integration network(PFINet)which mines the discriminative refined features of pedestrian images and fuses high-level and semantically strong features to build a robust pedestrian ***,PFINet first performs the feature extraction from concrete to abstract and the top-down semantic transfer to obtain multi-scale feature ***,the multi-scale feature maps are inputted to the discriminative-region response module to emphasize the identity-discriminative regions by the spatial attention ***,the pedestrian representation is obtained by the feature *** experiments demonstrate the effectiveness of PFINet which achieves the rank-1 accuracy of 81.95%and mAP of 74.49%on the multi-all evaluation mode of the SYSU-MM01 dataset.

关键词： person re-identification modality discrepancy discriminative feature

How to Wear Beautifully？ Clothing Pair Recommendation

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Journal of Computer Science & Technology 2018年第3期33卷 522-530页

作者： yu-jie liu Yong-Biao Gao Ling-Yan Bian Wen-Ya Wang Zong-Min Li College of Computer and Communication Engineering China University of Petroleum (East China) Qingdao 266580 China

In this paper, we present a practical system to automatically suggest the most pairing clothing items, given the reference clothing （upper-body or low-body）. This has been a challenge, due to clothes having a variety of categories. Clothing is one of the most informative cues for human appearance. In our daily life, people need to wear properly and beautifully to show their confidence, politeness and social status in various occasions. However, it is not easy to decide what to wear and how to coordinate their own clothes. To address this problem, we propose a recommendation approach that includes clothing region detection, clothing pair recommendation and distance fusion. Clothing region detection based on Faster R-CNN is used to detect clothing region. Clothing pair recommendation consists of a quadruple network architecture, where one dual network of the architecture adopts Siamese convolution neural network architecture. Training examples are pairs of upper-body and low-body clothing items that are either compatible or incompatible. The other dual network is used to learn clothing style features of the input image. This framework is designed to learn a feature transformation from the images of clothing items into two latent spaces, which we call them compatible space and style space respectively. After training the two dual networks, we use a distance fusion method to fuse the features extracted from the compatible and style dual networks. To acquire an optimized model and verify our proposed method, we expand an existing large clothing dataset WoG （Weather-to-Garment）, and the resulted dataset is called ＂How to Wear Beautifully＂（H2WB）. Experiments on the H2WB dataset demonstrate that our approach is effective with clothing region detection and clothing pair recommendation as well as distance fusion.

关键词： clothing recommendation clothing pair style learning

Reconstruction of the Medial Patellofemoral Ligament Using Hamstring Tendon Graft With Different Methods:a Biomechanical Study

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Chinese Medical Sciences Journal 2013年第4期28卷 201-205页

作者： Wei He yu-ming Yang Ming liu Ai-yuan Wang yu-jie liu Department of Orthopedics The 305 Hospital of Chinese People's Liberation Army Department of Orthopedics The 261 Hospital of Chinese People's Liberation Army Department of Orthopedics General Hospital of Chinese People's Liberation Army

Objective To measure the tensile strength of the normal medial patellofemoral ligament(MPFL),and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the *** Eight fresh cadaver knees were prepared by isolating the patella,leaving only the MPFL as its attachment to the medial condyle of *** MPFL was reconstructed by three different methods:four-suture fixation,anchors-single suture fixation,and anchors-double suture *** tensile strength and the elongation of the normal MPFL and the tendon grafts were *** The tensile strength of the four-suture fixation group(234.86±49.02 N)was stronger than that of the normal MPFL(146.91±25.30 N,P=0.0014)and the anchors-single suture group(159.17±49.07N,P=0.0077),while weaker than that of the anchors-double suture group(314.74±78.46 N,P=0.0052)Conclusions With regard to the tensile strength,the four-suture fixation method is reliable for clinical *** with the anchor-suture method,the four-suture fixation method which has no specific implants is more economical,convenient and efficient.

关键词： medial patellofemoral ligament biomechanics fixation method hamstring tendons

A review of energy and environment electrocatalysis based on high-index faceted nanocrystals

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Rare Metals 2021年第12期40卷 3406-3441页

作者： yun-Rui Li Ming-Xuan Li Shu-Na Li yu-jie liu Juan Chen Yao Wang State Key Laboratory of Heavy Oil Processing College of Chemical Engineering and EnvironmentChina University of PetroleumBeijing 102249China Department of Chemistry Tsinghua UniversityBeijing 100084China

Today,nanocrystals enclosed by high-index facets(HIFs)are attracting widely attentions of researchers due to their tremendous potential in the field of catalysis,especially in electrocatalysis,such as electro-oxidation of small organic molecule(such as formic acid,methanol,and ethanol),oxygen reduction reaction(ORR),hydrogen evolution reaction(HER),as well as the oxygen evolution reaction(OER).However,the practical applications of nanocrystals enclosed by HIFs still face many limitations in preparations of advanced electrocatalysts,including preparation strategy,limited life-time and *** development of advanced electrocatalysts enclosed with HIFs is crucial for solving these problems if the large-scale application of them is to be ***,we firstly detailedly demonstrate the identification methods of nanocrystals enclosed by HIFs,and then preparation strategies are elaborated in detail in this *** advanced nanocrystals enclosed by HIFs in electrocatalytic application are also summarized and we present representative achievements to further reveal the relationship of excellent electrocatalytic performance and nanocrystals with ***,we predict the remaining challenges and present our perspectives with regards of design strategies of improving electrocatalytic performance of Ptbased catalysts in the future.

关键词： Nanocrystals with high-index facets High surface free energy Electrocatalytic performance Water splitting Fuel cell