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HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3, XUE Qiong4.(1. school of Mechanical Engineering and Automation, wuhan Textile {2., wuhan 4.0073, hubei, china 2. State Key Laboratory of Material Processing and Die and Mould Technology, Huazhong {2. of Science and Technology, wuhan 4.0074. hubei, china 3. wuhan Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd, wuhan 4.0073, hubei, china 4. College of Science, wuhan university of Technology, wuhan 4.0079, hubei, china) [a] school of Mechanical Engineering and Automation Wuhan Textile University Wuhan 430073 Hubei China [b] State Key Laboratory of Material Processing and Die and Mould Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China [c] wuhan Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd Wuhan 430073 Hubei China [d] College of Science Wuhan University of Technology Wuhan 430079 Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

Electronic Structure of Doped Trans-Polyacetylene

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wuhan university Journal of Natural Sciences 2002年第1期7卷 51-53页

作者： Ren Da-zhi 1,2. Zhuang Wei 2. Wang Jun 2.1. wuhan university Journals Press,{4. 4.0072.{2.,china 2. school of Physics and Technology, wuhan university, {4. 4.0072.{2.,china wuhan university Journals Press Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C2.H2.)+n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated, by CNDO/2.method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease, of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.

关键词： trans polyacetylene CNDO/2 electronic structure doped

A Hybrid Genetic Algorithm for Reduct of Attributes in Decision System Based on Rough Set Theory

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wuhan university Journal of Natural Sciences 2002年第3期7卷 285-289页

作者： Dai Jian\|hua 1,2., Li Yuan\|xiang 1,2.,Liu Qun 3 1. State Key Laboratory of Software Engineering, wuhan university, wuhan 4.0072. {2.,china 2. school of computer, wuhan university, wuhan 4.0072. {2., china 3. school of {14. Science, wuhan university State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Chongqing university of Posts & Telecommunications School of Computer Science Chongqing China (GRID:grid.411587.e) (ISNI:***)

Knowledge reduction is an important issue when dealing with huge amounts of data. And it has been proved that computing the minimal reduct of decision system is NP-complete. By introducing heuristic information into genetic algorithm, we proposed a heuristic genetic algorithm. In the genetic algorithm, we constructed a new operator to maintaining the classification ability. The experiment shows that our algorithm is efficient and effective for minimal reduct, even for the special example that the simple heuristic algorithm can’t get the right result.

关键词： rough set reduction genetic algorithm heuristic algorithm

Integrating Audio-Visual Features and Text Information for Story Segmentation of News Video

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wuhan university Journal of Natural Sciences 2003年第4A期8卷 1070-1074页

作者： Liu Hua-yong, Zhou Dong-ru  school of computer,{2.,wuhan 4.0072. hubei, china wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

Video data are composed of multimodal information streams including visual, auditory and textual streams, so an approach of story segmentation for news video using multimodal analysis is described in this paper. The proposed approach detects the topic-caption frames, and integrates them with silence clips detection results, as well as shot segmentation results to locate the news story boundaries. The integration of audio-visual features and text information overcomes the weakness of the approach using only image analysis techniques. On test data with 135 4.0 frames, when the boundaries between news stories are detected, the accuracy rate 85.8% and the recall rate 97.5% are obtained. The experimental results show the approach is valid and robust.

关键词： news video story segmentation audio-visual features analysis text detection

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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Science china Earth Sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3, QU Jing1 & ZHAO Wenxia4.1. Graduate school, china {2. of Geosciences, wuhan 4.0074. china 2. Test Center, china {2. of Geosciences, wuhan 4.0074. china 3. Physics and Technology College, wuhan university, wuhan 4.0072. china 4. Test Center, Zhongshan {2., Guangzhou 5102.5, china china Univ Geosci Grad Sch Wuhan 430074 Peoples R China china Univ Geosci Test Ctr Wuhan 430074 Peoples R China wuhan Univ Phys & Technol Coll Wuhan 430072 Peoples R China Zhongshan Univ Test Ctr Guangzhou 510275 Peoples R China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.4.3 nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3m and Fd3m, respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974. is F4.32. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

Prediction of Tumor Outcome Based on Gene Expression Data

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wuhan university Journal of Natural Sciences 2004年第2期9卷 177-182页

作者： Liu Juan 1,2. Hitoshi Iba 3 1. school of computer, {2., {4. 4.0072. hubei, china 2. State Key Laboratory of Software Engineering, {4. 4.0072. hubei, china 3. Department of Frontier Informatics, university of Tokyo, Tokyo 113-8656, Japan wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) university of Tokyo Department of Frontier Informatics Tokyo Japan (GRID:grid.26999.3d) (ISNI:***)

Gene expression microarray data can be used to classify tumor types. We proposed a new procedure to classify human tumor samples based on microarray gene expressions by using a hybrid supervised learning method called MOEA+WV (Multi-Objective Evolutionary Algorithm+Weighted Voting). MOEA is used to search for a relatively few subsets of informative genes from the high-dimensional gene space, and WV is used as a classification tool. This new method has been applied to predicate the subtypes of lymphoma and outcomes of medulloblastoma. The results are relatively accurate and meaningful compared to those from other methods. Key words bioinformatics - tumor classification - Pareto optimization - MOEA CLC number Q 786 - TP 181 Foundation item: Supported by the National Natural Science Foundation of china (60301009), the Foundation of Young Scholars of Ministry of Education of china (150118) and Chenguang Project of {2. City (2.112.009).Biography: Liu Juan (1970-), female, Associate Professor, Postdoctoral, research direction: bioinformatics, data mining, machine learning.

关键词： bioinformatics tumor classification Pareto optimization MOEA

Commission Strategy of the Auction House

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wuhan university Journal of Natural Sciences 2006年第3期11卷 507-510页

作者： WANG Yan~ 1,2.1. College of Economics, Fudan university, Shanghai 2.04.3, china 2. {2. of Mathematics and Statistics, wuhan university , wuhan 4.0072. hubei, china College of Economics Fudan University 200433 Shanghai China school of Mathematics Statistics Wuhan University 430072 Wuhan Hubei China

In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders＇ equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage.

关键词： auction commission proportion Bayesian equilibrium bidding strategy

A Distributed Routing and Wavelength Assignment Algorithm for Online Multicast in All-Optical WDM Networks

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wuhan university Journal of Natural Sciences 2002年第1期7卷 27-36页

作者： Huang Chuan-he, Chen Xin-meng, Jia Xiao-hua school of computer, {2., wuhan 4.0072. hubei, china wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

Routing and wavelength assignment for online real-time multicast connection setup is a difficult task due to the dynamic change of availabilities of wavelengths on links and the consideration of wavelength conversion delay in WDM networks. This paper presents a distributed routing and wavelength assignment scheme for the setup of real-time multicast connections. It integrates routing and wavelength assignment as a single process, which greatly reduces the connection setup time. The proposed routing method is based on the Prim’s MST (Minimum Spanning Tree) algorithm and the K-restricted breadth-first search method, which can produce a sub-minimal cost tree under a given delay bound. The wave-length assignment uses the least-conversion and load balancing strategies. Simulation results show that the proposed algorithm is suitable for online multicast connection establishment in WDM networks.

关键词： Key words WDM networks routing and wavelength assignment multicast routing delay bounded routing

A Microenvironment, Rather than Chemical, Initiates the Cardiomyogenic Differentiation of Marrow Stromal Cells

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wuhan university Journal of Natural Sciences 2004年第4期9卷 513-521页

作者： LIU Wei-xin 1,2., SONG Jian 1 , WAN Yu 1, PAN Guo-dong 1 , LIU Yu 1 , CHENG Bang-chang 2.,CHEN Xi-chang 1 1. school of Medicine, wuhan university, {2. 4.0071, hubei, china 2. Renmin Hospital, wuhan university, {2. 4.0060, hubei, china wuhan university School of Medicine Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university Renmin Hospital Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university School of Medicine Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university Renmin Hospital Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

To investigate the potential of cardiomyogenic differentiation of rat bone marrow stromal cells (MSCs), they were exposed to 5-azacytidine tretments (single/repeat) at varying concentrations (3, 5, 10 μmol/L) and the fates of the cells were analyzed by immunocytochemistry, Western blot and the reporter gene of enhanced cyan fluorescent protein (ECFP) under the control of ventricular myosin light chain 2.(MLC2.) promoter. MSCs were also cocultured with cardiomyocytes for periods up to 16 days, the expression of cardiac myosin heavy chain (MHC) and troponin I (Tn I) proteins was analyzed. After the induction with 5-azacytidine, neither spontaneously beating cells nor myotubes were found; MHC and Tn I proteins were also undetectable and no ECFP-positive MSCs were detected. But when cocultured with cardiomyocytes, spontaneously contracting MSCs were observed and cardiac specific proteins could be detected. The results proved that the novel effects of 5-azacytidine on the cardiomyogenic differentiation of MSCs should be questioned and a direct intercellular communication with cardiomyocytes is necessary for MSCs to differentiate into cardiomyocytes. Key words cardiomyocyte - cell differentiation - stem cell CLC number Q 813.5 - R 54.0}2.2.Foundation item: Supported by the Natural Science Foundation of hubei Province (2.02.B00150)Biography: LIU Wei-xin (1976-), male, Ph. D candidate, research direction: stem cell and cellular biology.

关键词： cardiomyocyte cell differentiation stem cell