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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3 1. college of resources and Civil Engineering, Northeastern university, Shenyang 110004, china 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, beijing normal university, beijing 100875, china 3. college of Computer science and technology, Jilin university, Changchun 130012, china [a] college of resources and Civil Engineering Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] college of Computer science and technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

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An asymptotic result of super-Brownian motion on hyperbolic space

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Chinese science Bulletin 1997年第15期42卷 1240-1244页

作者： TANG JiashanDepartment of Mathematics, beijing normal university, beijing 100875, china Institute of Mathematics, Shantou university, Shantou 515063, china Department of Mathematics Beijing Normal University Beijing China Institute of Mathematics Shantou University Shantou China

SUPERPROCESS is one kind of measure-valued branching Markov processes. In the recentdecades many results of superprocesses on Euclidean spaces and on general abstract spaces havebeen obtained, but there is only little work on Riemannian manifold. In this note, wewill consider the super-Brownian motions on the hyperbolic space of dimension d and give anasymptotic result of this process (see Corollary 1 below). Iscoe investigated a similar prob-

关键词： hyperbolic space radial super-Brownian motion hitting probability asymptotic.

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Pointwise estimates for the maximal multilinear singular integral operators

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science china Mathematics 2005年第12期48卷 1696-1706页

作者： HU Guo’en, LI Dengfeng & LU Shanzhen Department of Applied Mathematics, university of Information Engineering, P. O. Box 1001 -747, Zhengzhou 450002, china college of Mathematical and Information sciences, Henan university, Kaifeng 475001, china Department of Mathematics, beijing normal university, beijing 100875, china 1. Department of Applied Mathematics University of Information Engineering P.O.Box 1001-747 450002 Zhengzhou China 2. college of Mathematical and Information sciences Henan University 475001 Kaifeng China 3. Department of Mathematics Beijing Normal University 100875 Beijing China

Two pointwise estimates relating the maximal multilinear singular integral operators and some classical maximal operators are established. These pointwise estimates imply the rearrangement estimate and the BLO(Rn) est... 详细信息

关键词： multilinear singular integral,maximal operator,BMO (Rn),BLO (Rn).

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Sedimentary facies of the Silurian tide-dominated paleo-estuary of the Tazhong area in the Tarim Basin

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Petroleum science 2008年第2期5卷 95-104页

作者： Zhang Jinliang Zhang Zhongjie college of Resource science and technology Beijing Normal University Beijing 100875 China School of Marine Geo-science Ocean University of China Qingdao Shandong 266100 China

As the relative sea-level rose, a paleo-estuary was formed by the marine inundation of the braided river incised valley during the period of the lower sub-member of the upper member of the Kalpingtage. formation of the Silurian in the Tarim Basin, west china. Sandstone-mudstone rhythmite, tidal structures and bimodal cross-bedding are common in these deposits, indicating that tides played a significant role in generating the sedimentary structures and the estuary type was tide-dominated. Five depositional facies were grouped： tidal river, sandy and muddy subtidal flat, tidal flat, tidal bar, tidal channel on the basis of lithology, electric properties, rhythmicity, sedimentary structure, fossil and the contact relationship. The sediment distribution showing first fining seaward and subsequent coarsening seaward from head to mouth, implies the two sediment sources in the paleo-estuary. The paleo-estuary of the Tarim Basin is very different from other representative estuaries. The most important distinction is that there are two adjacent estuaries joined by tidal flat onshore and by sandy and muddy subtidal flat in the sea at the same time, while the others only architecture model for the tide-dominated estuary. have one, So the Tazhong paleo-estuary shows a good

关键词： Tarim basin Silurian tide-dominated estuary tidal river tidal bar

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Azomethine ylide-formation from N-phthaloylglycine by photoinduced decarboxylation:A theoretical study

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中国科学:化学 2012年第10期42卷 1499-1500页

作者： FANG Qiu,DING LiNa & FANG WeiHai* college of Chemistry,beijing normal university,beijing 100875,china college of Chemistry beijing normal university beijing 100875 china

In this work,we report the first CASPT2//CASSCF study of the mechanism of the photodecarboxylation of *** charge transfer excited state SCT(1ππ*) is initially populated upon irradiation at 266 *** a result of a fast internal conversion to the lowest excited singlet state SCT-N(1ππ*),this state becomes a favorable precursor state for proton transfer,which triggers ***,the excited state intramolecular proton transfer(ESIPT) and decarboxylation processes proceed in an asynchronous concerted *** ESIPT process is accomplished in the SCT-N(1ππ*) state,but the CO2 molecule is finally formed in the ground state via the SCT/S0 conical *** ylide is formed in the ground state as a complex with CO2.A barrier of ～15 kcal/mol indicates that azomethine ylide is stable in the ground state,which is consistent with the experimental *** work provides mechanistic details about the formation of azomethine ylide by photoreaction of N-phthaloylglycine.

关键词： N-phthaloylglycine photodecarboxylation excited state intramolecular proton transfer CASPT2//CASSCF method

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PERFORMANCE AND INITIATION MECHANISM OF ISOPROPYLTHIOXANTHONE IN SURFACE PHOTOGRAFTING

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Chinese Journal of Polymer science 2000年第5期18卷 431-435页

作者： Wan-tai Yang Mei-zhen Yin Yu-feng Sun college of Material science and Engineering, beijing university of Chemical technology, beijing 100029, china beijing Univ Chem Technol Coll Mat Sci & Engn Beijing 100029 Peoples R China

In a polymerization model with low density polyethylene (LDPE) as the substrate and acrylic acid (AA) as the monomer, the performance of isopropylthioxanthone (ITX) in initiating surface photografting polymerization was evaluated. The results show that the reactivity of photopolymerization and photografting of ITX locate between benzophenone (BP) and benzildimethylketal (BDK) for polymerization, BDK > ITX > BP; for surface grafting polymerization, BP > ITX > BDK. These results can be explained by a reaction mechanism of the inter-molecular or intra-molecular hydrogen abstraction reaction of ITX.

关键词： photografting polymerization photopolymerization hydrogen abstraction reaction

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Challenges in the theoretical investigations of lipid membrane configurations

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Chinese Physics B 2013年第2期22卷 36-44页

作者：涂展春 Department of Physics Beijing Normal University Kavli Institute for Theoretical Physics china Chinese Academy of Sciences

We report some key results in the theoretical investigations of configurations of lipid membranes and present several challenges in this field,which involve（i）the exact solutions to the shape equation of lipid vesicles,（ii）the exact solutions to the governing equations of open lipid membranes,（iii）the neck condition of two-phase vesicles in the budding state,（iv） the nonlocal theory of membrane elasticity,and（v）the relationship between the symmetry and the magnitude of the free energy.

关键词： configuration lipid membrane

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Study on Tibetan Chicken embryonic adaptability to chronic hypoxia by revealing differential gene expression in heart tissue

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science china(Life sciences) 2009年第3期52卷 284-295页

作者： LI Mei & ZHAO ChunJiang college of Animal science and technology,china Agricultural university,beijing 100193,china 1. college of Animal science and technology China Agricultural University Beijing 100193 China

Oxygen concentration is essential for appropriate *** can exert a significant impact on physiological alteration of the cell and *** Chicken(Gallus gallus) is a Chinese indigenous breed inhabiting in Tibetan areas,which is also a chicken breed living at high altitude for the longest time in the *** has developed an adaptive mechanism to hypoxia,which is demonstrated by that Tibetan Chicken has much higher hatchability than low-land chicken breeds in high-altitude areas of *** the present study,Tibetan Chicken fertilized full sib eggs were incubated up to Hamburger-Hamilton stage 43 under 13% and 21% oxygen concentration,*** Chicken and Dwarf Recessive White Chicken were used as control *** hearts in all of the 3 chicken breeds under hypoxic and normoxic conditions were isolated and hybridized to Genechip Chicken Genome Array to study molecular mechanisms underlying the adaptation to high altitude of Tibetan *** a result,50 transcripts highly expressed in hypoxia are screened *** up-regulated genes,some are involved in the gene ontology(GO) such as cell growth,cell difference,muscle contraction and signal ***,the expression levels of 21 transcripts are lower in hypoxia than those in *** down-regulated genes take part in cell communication,ion transport,protein amino acid phosphorylation and signal ***,gene enrichment analyses of these differential gene expressions are mainly associated with immune system response and ion channel activity in response to ***,the transcriptional expression profiles analyzed by hierarchical clustering and CPP-SOM software in all of the 3 different chicken breeds revealed that Tibetan Chicken is much closely related to Shouguang Chicken rather than Dwarf Recessive White *** addition,12 transcripts of Tibetan Chicken breed-specific expressed genes were identified,which seem to result in a more

关键词： adaptation chronic hypoxia gene chip chicken genome array Tibetan Chicken(Gallus gallus) differential gene expression

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Complex variable method for plane elasticity of icosahedral quasicrystals and elliptic notch problem

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 773-780页

作者： LI LianHe1,2 & FAN TianYou1 1 Department of Physics, beijing Institute of technology, beijing 100081, china 2 college of Mathematics science, Inner Mongolia normal university, Hohhot 010022, china Department of Physics Beijing Institute of Technology Beijing 100081 China college of Mathematics science Inner Mongolia Normal University Hohhot 010022 China

The complex variable method for the plane elasticity theory of icosahedral quasicrystals is developed. Based on the general solution obtained previously, complex representations of stress and displacement components of phonon and phason fields in the quasicrystals are given. With the help of conformal transformation, an analytic solution for the elliptic notch problem of the material is presented. The solution of the Griffith crack problem can be observed as a special case of the results. The stress intensity factor and energy release rate of the crack are also obtained.

关键词： icosahedral quasicrystals plane elasticity elliptic notch complex variable method

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Birth-death processes on trees

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science china Mathematics 2010年第11期53卷 2993-3004页

作者： MA YuTao School of Mathematical sciences & Laboratory of Mathematics and Complex Systems, beijing normal university, beijing 100875, china 1. School of Mathematical sciences & Laboratory of Mathematics and Complex Systems Beijing Normal University Beijing 100875 China

In this paper, we consider birth-death processes on a tree T and we are interested when it is regular, recurrent and ergodic (strongly, exponentially). By constructing two corresponding birth death processes on Z+, we obtain computable conditions sufficient or necessary for that (in many cases, these two conditions coincide). With the help of these constructions, we give explicit upper and lower bounds for the Dirichlet eigenvalue λ0. At last, some examples are investigated to justify our results.

关键词： birth-death process tree ergodicity Dirichlet eigenvalue

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