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Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

Progress in Natural science:Materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2. FENG Zhijing1 and CHENG Kai3.1. State Key Laboratory of Tribiology, Tsinghua university, Beijing 100084, China 2. Department of Material {2.s, Changchun university of {2. and technology, Changchun 13.02., China 3. Faculty of Information and Engineering Systems, City Campus, Leeds LS1 3.E, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China Department of Material sciences Changchun University of Science and Technology Changchun 130021 China Faculty of Information and Engineering Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.2. nm root mean square (RMS) after 2. min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

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Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of Wuhan university of technology(Materials{2.) 2006年第4期21卷 146-149页

作者：霍凯成 Hubei Key Laboratory of Roadway Bridge & Structure Engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test

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A method of constructing a database-free optimal dynamical system and a global optimal dynamical system

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science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 905-915页

作者： WU ChuiJie1? & WANG Liang2.1 State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian university of technology, Dalian 11602., China 2.Research Center for Fluid Dynamics, School of{2.,{3., nanjing 2.1101, China 1. State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China 2. Research Center for Fluid Dynamics School of Science PLA University of Science and Technology Nanjing 211101 China

In this paper, to overcome the drawbacks of POT which minimize the reminder, not only the optimal functional with minimal residual is put forward, but also the method of global optimization is used. Under the condition of large reminder, the optimal bases can also be obtained through the method of POTres without the approaching of initial conditions. In addition, compared with local optimization, the advantage of global optimization is remarkable. On the one hand, we can expect that the dynamical system based on the global optimal bases will include more information than the ones based on the local optimal bases, since the global optimal bases are much more precise than the local optimal bases. On the other hand, from the point of view of error, the global optimal bases are independent of the choice of the object functional and the initial bases.

关键词： dynamical system residual global optimization

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Effect of Excipients on Stability and Structure of rhCuZn-SOD Encapsulated in PLGA Microspheres

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Chemical Research in Chinese Universities 2004年第3期20卷 323-327页

作者： LIU Ling 1,2.,GE Yu 1 and YUAN Qin-sheng 1 1. State Key Laboratory of Bioreactor Engineering and institute of Biochemistry,East China university of{2. and {3.,Shanghai 2.02.3},P. R. China 2. Public Health School,nanjing Medical university,nanjing 2.002.,P. R. China E China Univ Sci & Technol State Key Lab Bioreactor Engn Shanghai 200237 Peoples R China E China Univ Sci & Technol Inst Biochem Shanghai 200237 Peoples R China nanjing Med Univ Sch Publ Hlth Nanjing 210029 Peoples R China

When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 2.,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.

关键词： Poly( DL -lactide-co-glycolide)(PLGA) microsphere Recombinant human Cu Zn-superoxide dismutase(rhCu Zn-SOD) Fourier transform infrared(FTIR) spectroscopy Protein stability Excipient

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Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel

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science China(Technological sciences) 2004年第4期47卷 488-504页

作者： LIU Yan1,3. LIU Zhilin1, ZHANG Chengwei1,2.& ZHOU Yingchun1 1. Liaoning institute of {2., Jinzhou 12.001, China 2. China National Oil and Gas Exploration and Development Corporation, Beijing 100011, China 3. College of {2., Northeastern {3., Shengyang 110006, China 1. Liaoning institute of technology 121001 Jinzhou China 2. College of science Northeastern University 110006 Shengyang China 3. China National Oil and Gas Exploration and Development Corporation 100011 Beijing China

This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond n A with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference απ Using n A, S, απ we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.

关键词： valence electron structure, sulfide, hot brittleness, and rare earth.

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Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2. Lian Linsheng3. Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. College of Animal science and {2., China Agricultural {2., Beijing 100094, China 2. College of Biological science, China Agricultural {2., Beijing 100094, China 3. College of Animal science and {2., Yunnan Agricultural {2., Kunming 6502.1, China) College of Animal science and technology China Agricultural University Beijing 100094 China College of Biological science China Agricultural University Beijing 100094 China College of Animal science and technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2.2.(E4)-Asn and Ser-2.79(E4)-Gly were identified in exon 4 of the gene. The Lys-2.2.(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2.2.(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

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Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua science and technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2., Yuanyuan Dan 3., Sen Xu 4 1. School of Computer science and Engineering, Jiangsu {2. of science and {3., Zhenjiang 2.2.03. China 2. Department of Radiology, Carver College of Medicine, The {2. of Iowa, Iowa City, IA 52.42. USA 3. School of Biology and Chemical Engineering, Jiangsu {2. of science and {3., Zhenjiang 2.2.03. China 4. School of Information Engineering, Yancheng {12. of {3., Yancheng 2.4051, China School of Computer science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China|c|

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

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NUMERICAL SIMULATIONS OF SEA ICE WITH DIFFERENT ADVECTION SCHEMES

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Journal of Hydrodynamics 2011年第3期23卷 372-378页

作者： LIU Xi-ying State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China institute of meteorology PLA University of Science and Technology Nanjing 211101 China

Numerical simulations are carried out for sea ice with four different advection schemes to study their effects on the simulation results. The sea ice model employed here is the Sea Ice Simulator （SIS） of the Geophysical Fluid Dynamics Laboratory （GFDL） Modular Ocean Model version 4b （MOM4b） and the four advection schemes are, the upwind scheme originally used in the SIS, the Multi-Dimensional Positive Advection （MDPA） scheme, the Incremental Remapping Scheme （IRS） and the Two Step Shape Preserving （TSSP） scheme. The latter three schemes are newly introduced. To consider the interactions between sea ice and ocean, a mixed layer ocean model is introduced and coupled to the SIS. The coupled model uses a tri-polar coordinate with 12.x65 grids, covering the whole earth globe, in the horizontal plane. Simulation results in the northern high latitudes are analyzed. In all simulations, the model reproduces the seasonal variation of sea ice in the northern high latitudes well. Compared with the results from the observation, the sea ice model produces some extra sea ice coverage in the Greenland Sea and Barents Sea in winter due to the exclusion of ocean current effects and the smaller simulated sea ice thickness in the Arctic basin. There are similar features among the results obtained with the introduced three advection schemes. The simulated sea ice thickness with the three newly introduced schemes are all smaller than that of the upwind scheme and the simulated sea ice velocities of movement are all smaller than that of the upwind scheme. There are more similarities shared in the results obtained with the MPDA and TSSP schemes.

关键词： advection scheme sea ice simulation

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Communication network designing:Transmission capacity,cost and scalability

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science China(Information sciences) 2012年第11期55卷 2454-2465页

作者： ZHANG GuoQiang1,2.3.& ZHANG GuoQing1 1institute of Computing {2.,Chinese Academy of {2.s,Beijing 100190,China 2.chool of Computer {2. and {2.,nanjing Normal university,nanjing 2.0046,China 3.rovincial Key Laboratory for Computer Information Processing {2.,Soochow university,Suzhou 2.5000,China 1. institute of Computing technology Chinese Academy of Sciences Beijing 100190 China2. School of Computer Science and Technology Nanjing Normal University Nanjing 210046 China3. Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215000 China

Despite the growing number of works centering around the traffic dynamics on complex networks,these researches still have some common shortcomings,e.g.,too simple traffic flow model and lack of considerations for the designing cost and scalability *** paper builds on a more realistic traffic flow model,and offers a holistic view on the network designing *** addition to the extensively studied transmission capacity,this paper takes designing cost and scalability as two other designing objectives,and presents a quantitative study of how different designing choices independently and collectively influence these objectives by the introduction of a cartesian coordinate *** is shown that different kinds of network topologies display different shapes of achievable solution spaces and exhibit different abilities to achieve cost-effective and scalable *** particular,we find the philosophy underlying empirical network designing and engineering today fails to meet the cost-effective and scalable designing requirements,and propose a cost-effective and scalable designing scheme for BA-like networks,i.e.,the efficient routing combined with effective betweenness based link bandwidth *** addition,when designing a thoroughly new network from the beginning,we find that ER network is a good candidate to achieve cost-effective and scalable designing in most settings.

关键词： cost-effective communication network designing network transmission efficiency network topology traffic dynamics next generation network scalable network designing

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Intuitionistic fuzzy hierarchical clustering algorithms

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Journal of Systems Engineering and Electronics 2009年第1期20卷 90-97页

作者： Xu Zeshui1,2.1. Coll. of Economics and Management, Southeast Univ., nanjing 2.0096, P. R. China 2. Inst. of sciences, {2. Univ. of science and technology, nanjing 2.0007, P. R. China Coll. of Economics and Management Southeast Univ. Nanjing 210096 P. R. China Inst. of sciences PLA Univ. of Science and Technology Nanjing 210007 P. R. China

Intuitionistic fuzzy set （IFS） is a set of 2.tuple arguments, each of which is characterized by a membership degree and a nonmembership degree. The generalized form of IFS is interval-valued intuitionistic fuzzy set （IVIFS）, whose components are intervals rather than exact numbers. IFSs and IVIFSs have been found to be very useful to describe vagueness and uncertainty. However, it seems that little attention has been focused on the clustering analysis of IFSs and IVIFSs. An intuitionistic fuzzy hierarchical algorithm is introduced for clustering IFSs, which is based on the traditional hierarchical clustering procedure, the intuitionistic fuzzy aggregation operator, and the basic distance measures between IFSs： the Hamming distance, normalized Hamming, weighted Hamming, the Euclidean distance, the normalized Euclidean distance, and the weighted Euclidean distance. Subsequently, the algorithm is extended for clustering IVIFSs. Finally the algorithm and its extended form are applied to the classifications of building materials and enterprises respectively.

关键词： intuitionistic fuzzy set interval-valued intuitionistic fuzzy set hierarchical clustering intuitionisticfuzzy aggregation operator distance measure.

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