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Electron transport properties of boron-doped capped-carbon-nanotube-based molecular junctions

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science Bulletin 2010年第36期55卷 4104-4107页

作者： ZHAO Peng1 & LIU DeSheng2.1 school of science, {2. of jinan, jinan 2.002., china 2.school of Physics, State Key Laboratory of Crystal Materials, shandong university, jinan 2.0100, china school of science University of Jinan Jinan 250022 China school of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

Using the Landauer formalism that combines both the non-equilibrium Green’s function and first-principles density functional theory, the electron transport properties of a one-dimensional molecular junction based on capped carbon nanotubes with boron doping at various sites are investigated. The results show that the electron transport properties are strongly dependent on the boron-doping site. Negative differential resistance behavior can be observed when boron-atom dopants are present in the tip region.

关键词： carbon nanotube doping non-equilibrium Green’s function density functional theory

Precise point positioning and its application in mining deformation monitoring

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中国有色金属学会会刊：英文版 2011年第S3期21卷 499-505页

作者： XU Chang-hui1, 2. WANG Jin-ling2. GAO Jing-xiang1, WANG Jian1, HU Hong1 1. school of Environment and Spatial information,{2. university of Mining and Technology, Xuzhou 2.116,{2. 2. school of Surveying and Spatial information Systems, university of New South Wales, Sydney 2.52. Australia [a] school of Environment and Spatial information China University of Mining and Technology Xuzhou 22116 China [b] school of Surveying and Spatial information Systems University of New South Wales Sydney 2052 Australia

Precise point positioning (PPP)-based deformation monitoring scheme is presented for the use in mining deformation monitoring. Within the solutions of daily observation, outliers are detected and removed to avoid any potential misinterpretation of the results and then the deformation can be extracted by the coordinate differences between the two consecutive solutions. Meanwhile, because of the special location of a rover station in mining areas, the satellite geometry may be insufficient for a reasonable PPP solution, and the multipath impact an also be significant. Therefore, it is necessary to predict the satellite geometry before any daily observation. To evaluate the ability of extracting the deformation using the PPP-based method, various quality measures were introduced. The results of three datasets of the same station show that the precision of deformation monitored by PPP can reach up to cm level and even mm level.

关键词： precise point positioning deformation monitoring outlier identification geometry multipath

The Coagulation Process of Nascent Fibers in PAN Wet-spinning

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Journal of Wuhan university of Technology(Materials science) 2010年第2期25卷 200-205页

作者：陈娟葛曷一 school of Material science and Engineering University of Jinan

The evolvement of microstructure and properties of nascent fibers during coagulation process in the polyacrylonitrile （PAN） wet-spinning and the effect of coagulation bath conditions on the structure and properties of the nascent fibers were investigated by the means of X-ray diffraction （XRD）, scanning electron microscope （SEM）, fiber fineness machine, fiber tensile strength machine, etc. The experimental results indicate that the nascent fibers become denser and have fewer inner defects, the diameter of nascent fibers shrink and the crystallization degree of nascent fibers gradually increases with the increasing of coagulation time. Too large spinning tension leads to grooves occurring on surface of fibers. To obtain circular cross-section of nascent fibers the optimal coagulation conditions are 50 ℃, 65% （concentration） and 0.9 （draw ratio）.

关键词： PAN wet-spinning coagulation nascent fibers

Image denoising and deblurring: non-convex regularization, inverse diffusion and shock filter

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science china({2. sciences) 2011年第6期54卷 1184-1198页

作者： FU ShuJun 1,2.3 , ZHANG CaiMing 2.& TAI XueCheng 3,4 1 school of Mathematics, shandong university,{2., china 2.school of Computer science and Technology, shandong university, jinan 2.0101, china 3 school of Physical and Mathematical sciences, Nanyang Technological university, Singapore 639798, Singapore 4 Department of Mathematics, university of Bergen, Bergen 5008, Norway 1. school of Mathematics Shandong University Jinan 250100 China2. School of Computer Science and Technology Shandong University Jinan 250101 China3. School of Physical and Mathematical Sciences Nanyang Technological University Singapore 639798 Singapore4. Department of Mathematics University of Bergen Bergen 5008 Norway

A large number of applications in image processing and computer vision depend on image quality. In this paper, main concerns are image denoising and deblurring simultaneously in a restoration task by three types of methodologies: non-convex regularization, inverse diffusion and shock filter. We discuss their relations in the context of image deblurring: the inverse diffusion implied by the non-convex regularization, and the superior ability of deblurring edge of the shock filter to that of the inverse diffusion, both in 1D and 2. cases. Finally, we propose a region-based adaptive anisotropic diffusion with shock filter method, which shows advantages of deblurring edges, denoising and smoothing contours in experiments, compared with some related methods. Therein an idea of "divide and rule" is introduced.

关键词： image denoising image deblurring non-convex regularization inverse diffusion shock filter adaptive anisotropic diffusion

A 14/11-approximation algorithm for sorting by short block-moves

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science china({2. sciences) 2011年第2期54卷 279-292页

作者： JIANG HaiTao & ZHU DaMing school of Computer science and Technology,{2., jinan 2.0101, china 1. school of Computer science and Technology Shandong University Jinan 250101 China

Block-move is one of the popular operations for genome rearrangement. A short block-move is an operation on a permutation that moves an element at most two positions away from its original position. Heath and Vergara investigated the problem of finding a minimum-length sorting sequence of short block-moves for a given permutation and devised a 4/3-approximation algorithm. In this paper, we present a new 14/11-approximation algorithm for this problem. Firstly, we devise an exact polynomial time algorithm for sorting a special kind of sub permutations called umbrella; then we split the permutation into a series of related umbrellas and sort them greedily. We obtain a new lower bound of the short block-move distance by exploiting the properties of five kinds of sub-permutations. After some complicated analysis, we prove that the approximation ratio of the new algorithm is at most 14/11.

关键词： short block-move approximation algorithm

A Hybrid of Theorems of Goldbach and Piatetski-Shapiro

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Chinese Annals of Mathematics,Series B 2006年第3期27卷 341-352页

作者： Xianmeng MENG Mingqiang WANG school of Computer science and Technology,{2., jinan 2.0100, china Department of Statistics and Mathematics, shandong Finance Institute, jinan 2.0014, china. school of Computer science and Technology,{2., jinan 2.0100, china Department of Mathematics, Qufu Normal university, Qufu 2.3165, shandong, china. school of Computer science and Technology Shandong University Jinan 250100 China Department of Statistics and Mathematics Shandong Finance Institute Jinan 250014 China Department of Mathematics Qufu Normal University Qufu 273165 Shandong China

It is proved that for almost all sufficiently large even integers n, the prime variable equation n = p1 ＋ p2. p1 ∈ Pγ is solvable, with 13/15 〈γ≤ 1, where Pγ = {p ｜p = [m^1/γ], for integer m and prime p} is t... 详细信息

关键词： Circle method Sieve method Goldbach problem

Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2. ZHANG Yin-ling1, 2. WANG Fei 1 ,2. ZHANG Zhen-hui 3, GUO Yu-xiang1, 2.1. Key Laboratory of Mine Spatial information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003,{2. 2. school of Surveying and land information Engineering, Henan Polytechnic university, Jiaozuo 454003,{2. 3. Qingdao Branch of Naval Aeronautical Engineering Institute, Qingdao 2.6041,{2. Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

Electronic structure and magnetic properties of SmCo7-xTix

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science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 38-45页

作者： ZHANG Changwen1, LI Hua1, DONG Jianmin1, GUO Yongquan2.& LI Wei2.1. school of Physics and Microelectronics, shandong university,{2., china 2. Institute of Functional Materials, Central Iron and Steel Research Institute, Beijing 100081, china 1. school of Physics and Microelectronics Shandong University Jinan 250100 China 2. Institute of Functional Materials Central Iron and Steel Research Institute Beijing 100081 China

Electronic structure of SmCo7-xTix alloy has been studied by means of the spin-polarized MS-Xα method. It is shown that a few of electrons are transferred to Sm(5d) orbital due to orbital hybridization between Sm and Co atoms. The exchange interaction between 5d-3d electrons is stronger, which is the main reason resulting in the long-range ferromagnetic order between Co and Sm atoms. The Curie temperature of SmCo7-xTix is generally lower than that of pure Co metal, which may be explained by the weaker aver- age of coupling strength between Co sites due to some negative exchange couplings occurring mainly at 2. site. The calculated results for the Sm5Co2.Ti6 cluster may lead to a better understanding of why SmCo7-xTix is stable phase. Since the negative interaction of 2. sites weakens and the bonding at EF strengthens with increasing Ti concentration, which result in the decrease in the free energy of the alloy, the stable ferromagnetic order forms inside SmCo7-xTix. Considering the localization of 4f states and 5d moment arising from the orbital hybridization, the calculated moment is 9.47μB per formula unit that is in agreement with experiments.

关键词： electronic structure, spin polarization, atomic magnetic moment, exchange coupling, Curie temperature.

Detecting malignant patients via modified boosted tree

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science china({2. sciences) 2010年第7期53卷 1369-1378页

作者： DONG CaiLing1, YIN YiLong1 & YANG XiuKun2.1school of Computer science and Technology,{2., jinan 2.0101, china 2.ollege of information and Communication, Harbin Engineering university, Harbin 150001, china 1. school of Computer science and Technology Shandong University Jinan 250101 China2. College of Information and Communication Harbin Engineering University Harbin 150001 China

As one of the most effective measures to extract useful information from medical database and provide scientific decision-making for diagnosis and treatment of diseases, medical data mining has become an increasingly hot topic in the last few years. Some of the intrinsic characteristics of medical databases, such as the huge volume and imbalanced samples as well as stringent performance standards, make this mining process particularly challenging. By elaborating various challenges existing in Task 1 of KDD Cup 2.08 competition, this paper analyzes some potential solutions to these problems and presents a modified boosted tree as the final classification model. This model ranked the fourth among all the solutions to Task 1. We hope that our analysis and solutions to these challenges would contribute to the development of medical data mining applications.

关键词： classification boosted tree multiple instances scoring Real AdaBoost breast cancer detection medical data mining