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Friction Behaviors of the Hot Filament Chemical Vapor Deposition Diamond Film under Ambient Air and Water Lubricating Conditions

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Chinese Journal of Mechanical Engineering 2009年第5期22卷 658-664页

作者： shen bin SUN Fanghong School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

The friction behavior of the hot filament chemical vapor deposition（HFCVD） diamond film plays a critical role on its applications in mechanical fields and largely depends on the environment. Studies on the tribological properties of HFCVD diamond films coated on Co-cemented tungsten carbide （WC-Co） substrates are rarely reported in available literatures, especially in the water lubricating conditions. In this paper, conventional microcrystalline diamond（MCD） and fine-grained diamond（FGD） films are deposited on WC-Co substrates and their friction properties are evaluated on a reciprocating ball-on-plate tribometer, where they are brought to slide against ball-bearing steel and copper balls in dry and water lubricating conditions. Scanning electron microscopy（SEM）, atomic force microscopy（AFM）, surface profilometer and Raman spectroscopy are adopted to characterize as-deposited diamond films; SEM and energy dispersive X-ray（EDX） are used to investigate the worn region on the surfaces of both counterface balls and diamond films. The research results show that the friction coefficient of HFCVD diamond films always starts with a high initial value, and then gradually transits to a relative stable state. For a given counterface and a sliding condition, the FGD film presents lower stable friction coefficients by 0.02-0.03 than MCD film. The transferred materials adhered on sliding interface are supposed to have predominate effect on the friction behaviors of HFCVD diamond films. Furthermore, the effect of water lubricating on reducing friction coefficient is significant. For a given counterpart, the stable friction coefficients of MCD or FGD films reduce by about 0.07-0.08 while sliding in the water lubricating condition, relative to in dry sliding condition. This study is beneficial for widespread applications of HFCVD diamond coated mechanical components and adopting water lubricating system, replacing ofoil lubricating, in a variety of mechanical processing fields to im

关键词： Hot filament chemical vapor deposition(HFCVD) diamond films friction behavior water lubricating

Holomorphic Maps from Sasakian Manifolds into Khler Manifolds

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Chinese Annals of Mathematics,Series B 2013年第4期34卷 575-586页

作者： bin shen Yibing shen Xi ZHANG Department of Mathematics Southeast University Department of Mathematics Zhejiang University Department of Mathematics Zhejiang University

The authors consider ±（Φ, J）-holomorphic maps from Sasakian manifolds into Koihler manifolds, which can be seen as counterparts of holomorphic maps in Kiihler ge- ometry. It is proved that those maps must be harmonic and basic. Then a Schwarz lemma for those maps is obtained. On the other hand, an invariant in its basic homotopic class is obtained. Moreover, the invariant is just held in the class of basic maps.

关键词： Sasakian manifold Harmonic Schwarz lemma Homotopic invariant

Regularized canonical correlation analysis with unlabeled data

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 504-511页

作者： Xi-chuan ZHOU Hai-bin shen Institute of VLSI Design Zhejiang University Hangzhou 310027 China

In standard canonical correlation analysis (CCA), the data from definite datasets are used to estimate their canonical correlation. In real applications, for example in bilingual text retrieval, it may have a great portion of data that we do not know which set it belongs to. This part of data is called unlabeled data, while the rest from definite datasets is called labeled data. We propose a novel method called regularized canonical correlation analysis (RCCA), which makes use of both labeled and unlabeled samples. Specifically, we learn to approximate canonical correlation as if all data were labeled. Then, we describe a generalization of RCCA for the multi-set situation. Experiments on four real world datasets, Yeast, Cloud, Iris, and Haberman, demonstrate that, by incorporating the unlabeled data points, the accuracy of correlation coefficients can be improved by over 30%.

关键词： Canonical correlation analysis (CCA) Regularization Unlabeled data Generalized canonical correlation analysis(GCCA)

Friction and Wear Performance of Boron Doped, Undoped Microcrystalline and Fine Grained Composite Diamond Films

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 155-163页

作者： WANG Xinchang WANG Liang shen bin SUN Fanghong School of Mechanical Engineering Shanghai Jiao Tong University

Chemical vapor deposition （CVD） diamond films have attracted more attentions due to their excellent mechanical properties. Whereas as-fabricated traditional diamond films in the previous studies don＇t have enough adhesion or surface smoothness, which seriously impact their friction and wear performance, and thus limit their applications under extremely harsh conditions. A boron doped, undoped microcrystalline and fine grained composite diamond （BD-UM-FGCD） film is fabricated by a three-step method adopting hot filament CVD （HFCVD） method in the present study, presenting outstanding comprehensive performance, including the good adhesion between the substrate and the underlying boron doped diamond （BDD） layer, the extremely high hardness of the middle undoped microcrystalline diamond （UMCD） layer, as well as the low surface roughness and favorable polished convenience of the surface fine grained diamond （FGD） layer. The friction and wear behavior of this composite film sliding against low-carbon steel and silicon nitride balls are studied on a ball-on-plate rotational friction tester. Besides, its wear rate is further evaluated under a severer condition using an inner-hole polishing apparatus, with low-carbon steel wire as the counterpart. The test results show that the BD-UM-FGCD film performs very small friction coefficient and great friction behavior owing to its high surface smoothness, and meanwhile it also has excellent wear resistance because of the relatively high hardness of the surface FGD film and the extremely high hardness of the middle UMCD film. Moreover, under the industrial conditions for producing low-carbon steel wires, this composite film can sufficiently prolong the working lifetime of the drawing dies and improve their application effects. This research develops a novel composite diamond films owning great comprehensive properties, which have great potentials as protecting coatings on working surfaces of the wear-resistant and anti-frictional com

关键词： BD-UM-FGCD film HFCVD friction behavior wear performance application

An improved analytical model of cutting temperature in orthogonal cutting of Ti6Al4V

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Chinese Journal of Aeronautics 2019年第3期32卷 759-769页

作者： Chenwei SHAN Xu ZHANG bin shen Dinghua ZHANG Key Laboratory of Modern Design and Integrated Manufacturing Technology of Ministry of Education Northwestern Polytechnical University 206 Institution North Electronics Research Institute Co. Ltd

Cutting heat has significant effects on the machined surface integrity of titanium alloys in the aerospace field. Many unwanted problems such as surface burning, work hardening, and tool wear can be induced by high cutting temperatures. Therefore, it is necessary to accurately predict the cutting temperature of titanium alloys. In this paper, an improved analytical model of the cutting temperature in orthogonal cutting of titanium alloys is proposed based on the Komanduri-Hou model and the Huang-Liang model. The temperatures at points in a cutting tool, chip, and workpiece are calculated by using the moving heat source method. The tool relief angle is introduced into the proposed model, and imaginary mirrored heat sources of the shear plane heat source and the frictional heat source are applied to calculate the temperature rise in a semi-infinite medium. The heat partition ratio along the tool-chip interface is determined by the discretization method. For validation purpose, orthogonal cutting of titanium alloy Ti6Al4V is performed on a lathe by using a sharp tool. Experimental results show to be consistent well with those of the proposed model,yielding a relative difference of predicted temperature from 0.49% to 9.00%. The model demonstrates its ability of predicting cutting temperature in orthogonal cutting of Ti6Al4V.

关键词： Cutting temperature Moving heat source method Orthogonal cutting Relief angle Titanium alloy

Observations of the Singlets of Higher-Degree Modes Based on the OSE

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Journal of Earth Science 2018年第6期29卷 1398-1408页

作者： Shi-Yu Zeng Wen-bin shen School of Geodesy and Geomatics/Key Laboratory of the Geospace Environment and Geodesy Wuhan University State Key Laboratory for Information Engineering in Surveying Mapping and Remote SensingWuhan University

In this study,we selected 18 SG（superconducting gravimeter）records from 15 GGP stations with 99 vertical and 69 horizontal components of IRIS broad-band seismograms during 2004 Sumatra Earthquake to detect the splitting of higher-degree Earth’s free oscillations modes（0S4,0S7〈sub〉0S10,2S4,1S5,2S5,1S6）and 12 inner-core sensitive modes（25S2,27S2,6S3,9S3,13S3,15S3,11S4,18S4,8S5,11S5,23S5,16S6）by using OSE（optimal sequence estimation）method which only considers *** indicate that OSE can completely isolate singlets of high-degree modes in time-domain,effectively resolve the coupled multiplets independently,and reduce the possibility of mode mixing and end effect,showing that OSE could improve some signals’signal-to-noise *** the results of SG records with seismic data sets suggests that the number of SG records is inadequate to detect all singlets of higher *** we mainly selected plentiful seismograms of IRIS to observe the multiplets of higher *** estimate frequencies of the singlets using AR method and evaluate the measurement error using bootstrap ***,we compared the observations with the predictions of PREM-tidal *** study demonstrates that OSE is effective in isolating singlets of Earth’s free oscillations with higher *** experimental results may provide constraints to the construction of 3D Earth model.

关键词： free oscillation mode splitting detection high-degree modes OSE

Level Structure of 83Rb in the Projected Shell Model

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Communications in Theoretical Physics 2002年第10期38卷 465-469页

作者： DING bin-Gang shen Shui-Fa Huzhou Teachers College Huzhou 313000 China Shanghai Institute of Nuclear Research the Chinese Academy of Sciences Shanghai 201800 China

The projected shell model is applied to the odd-proton nucleus 83 Rb. The results of theoretical calculationsabout the excited positive-parity yrast states and the negative-parity ground-state band are compared with experimentaldata, and the best reproduction of the experiment has been given by this model. In addition, a band diagram calculatedfor the negative-parity g.s. band is also shown in order to extract physics out of the numerical results.

关键词： projected shell model, yrast state, quadrupole deformation

Deep model-based feature extraction for predicting protein subcellular localizations from bio-images

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Frontiers of Computer Science 2017年第2期11卷 243-252页

作者： Wei SHAO Yi DING Hong-bin shen Daoqiang ZHANG School of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 211106 China Institute of Image Processing and Pattern Recognition Shanghai Jiao Tong University Shanghai 200240 China

Protein subcellular localization prediction is im- portant for studying the function of proteins. Recently, as significant progress has been witnessed in the field of mi- croscopic imaging, automatically determining the subcellular localization of proteins from bio-images is becoming a new research hotspot. One of the central themes in this field is to determine what features are suitable for describing the pro- tein images. Existing feature extraction methods are usually hand-crafted designed, by which only one layer of features will be extracted, which may not be sufficient to represent the complex protein images. To this end, we propose a deep model based descriptor （DMD） to extract the high-level fea- tures from protein images. Specifically, in order to make the extracted features more generic, we firstly trained a convolu- tion neural network （i.e., AlexNe0 by using a natural image set with millions of labels, and then used the partial parame- ter transfer strategy to fine-tnne the parameters from natural images to protein images. After that, we applied the Lasso model to select the most distinguishing features from the last fully connected layer of the CNN （Convolution Neural Net- work）, and used these selected features for final classifica- tions. Experimental results on a protein image dataset vali- date the efficacy of our method.

关键词： partial parameter transfer subcellular location classification feature extraction deep model convolution neural network

Bioimage-based protein subcellular location prediction： a comprehensive review

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Frontiers of Computer Science 2018年第1期12卷 26-39页

作者： Ying-Ying XU Li-Xiu YAO Hong-bin shen Institute of Image Processing and Pattern Recognition Shanghai Jiao Tong University Shanghai 200240 China Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai 200240 China

Subcellular localization of proteins can provide key hints to infer their functions and structures in cells. With the breakthrough of recent molecule imaging techniques, the usage of 2D bioimages has become increasingly popular in automatically analyzing the protein subcellular location pat- terns. Compared with the widely used protein 1D amino acid sequence data, the images of protein distribution are more intuitive and interpretable, making the images a better choice at many applications for revealing the dynamic char- acteristics of proteins, such as detecting protein translocation and quantification of proteins. In this paper, we systemati- cally reviewed the recent progresses in the field of automated image-based protein subcellular location prediction, and clas- sified them into four categories including growing of bioim- age databases, description of subcellular location distribution patterns, classification methods, and applications of the pre- diction systems. Besides, we also discussed some potential directions in this field.

关键词： bioimage informatics protein subcellular loca-tion prediction global and local features multi-location pro-tein recognition