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Fluorite REE characteristics of the Diyanqinamu Mo deposit,Inner Mongolia, China

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Chinese Journal Of Geochemistry 2015年第4期34卷 610-619页

作者： Long jian Hairui Sun jian'guo gao Faculty of Land Resource Engineering Kunming University of Science and Technology Development and Research Center of China Geological Survey National Exploration and Development Planning Technical Guidance Center in Ministry of Land and Resorces China University of Geosciences State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences

The Diyanqinamu Mo deposit, a newly discovered porphyry deposit in the northern-central part of the Great Xing'an Range, Inner Mongolia, China, is characterized by widely distributed fluorite. It is important to note that almost all the fluorite that is paragenetic with molybdenite is purple. The Tb/Ca–Tb/La ratios of these purple fluorite samples show that they have a hydrothermal *** unidirectional solidification texture at the apex of the aplitic granite and the low F contents in the andesite suggest that most of F in fluorite was derived from granitic melts. These observations suggest that the fluorite was related to the magmatic-hydrothermal fluids. All the fluorite separates have consistent total REE contents with LREE-depleted, HREE-enriched, negative Eu anomaly,unapparent Ce anomaly and positive Y anomaly. These characteristics are significantly different than those of country granite, andesite and tuff whole-rock. The positive Y anomaly of the fluorite separates implies that the hydrothermal fluids migrated a long distance, as suggested by the fact that the fluorite-molybdenite veins were mostly hosted in andesite and tuff, far from the Mo ore-forming granites. The features of LREE-depleted and HREE-enriched fluorite are due to the REE-complex in the F-enriched fluids during migration. The stronger negative Eu anomaly of fluorite than those of country rocks suggests that the Eu anomaly of the original hydrothermal fluid was enhanced by the high temperature(generally above 200 or250 °C). The widespread magnetite in the studied deposit indicates that the magmatic-hydrothermal fluid was oxidized at early stage. On the other hand, the pyrite was also paragenetic, with the molybdenite and unapparent Ce anomaly implying that the hydrothermal fluid probably experienced oxygen fugacity decreasing during migration,which is important for Mo mineralization.

关键词：钼矿床稀土元素特征内蒙古萤石中国热液成因岩浆热液迁移过程

A randomized diversification strategy for solving satisfiability problem with long clauses

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Science China(Information Sciences) 2017年第9期60卷 121-131页

作者： jian gao Ruizhi LI Minghao YIN College of Computer Science Northeast Normal University College of Information Science and Technology Dalian Maritime University Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University

Satisfiability problem(SAT) is a central problem in artificial intelligence due to its computational complexity and usefulness in industrial applications. Stochastic local search(SLS) algorithms are powerful to solve hard instances of satisfiability problems, among which CScore SAT is proposed for solving SAT instances with long clauses by using greedy mode and diversification mode. In this paper, we present a randomized variable selection strategy to improve efficiency of the diversification mode, and thus propose a new SLS *** perform a number of experiments to evaluate the new algorithm comparing with the recently proposed algorithms, and show that our algorithm is comparative with others for solving random instances near the phase transition threshold.

关键词： SAT local search randomized diversification strategy phase transition long clause

Automatic differentiation based discrete adjoint method for aerodynamic design optimization on unstructured meshes

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Chinese Journal of Aeronautics 2017年第2期30卷 611-627页

作者： Yisheng gao Yizhao Wu jian Xia College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A systematic methodology for formulating,implementing,solving and verifying discrete adjoint of the compressible Reynolds-averaged Navier-Stokes（RANS） equations for aerodynamic design optimization on unstructured meshes is ***,a general adjoint formulation is constructed for the entire optimization problem,including parameterization,mesh deformation,flow solution and computation of the objective function,which is followed by detailed formulations of matrix-vector products arising in the adjoint *** to this formulation,procedural components of implementing the required matrix-vector products are generated by means of automatic differentiation（AD） in a structured and modular ***,a duality-preserving iterative algorithm is employed to solve flow adjoint equations arising in the adjoint model,ensuring identical convergence rates for the tangent and the adjoint models.A three-step strategy is adopted to verify the adjoint *** proposed method has several remarkable features：the use of AD techniques avoids tedious and error-prone manual derivation and programming;duality is strictly preserved so that consistent and highly accurate discrete sensitivities can be obtained;and comparable efficiency to hand-coded implementation can be *** the current discrete adjoint method,a gradient-based optimization framework has been developed and applied to a drag reduction problem.

关键词： Automatic differentiation(AD) Discrete adjoint Navier-Stokes equations Optimization Unstructured meshes

Visual attention based model for target detection in large-field images

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Journal of Systems Engineering and Electronics 2011年第1期22卷 150-156页

作者： Lining gao Fukun Bi jian Yang Department of Electronic Engineering Tsinghua University Beijing 100084 P. R. China School of Information and Electronics Beijing Institute of Technology Beijing 100081 E R. China

It is of great significance to rapidly detect targets in large-field remote sensing images,with limited computation *** relative achievements of visual attention in perception psychology,this paper proposes a hierarchical attention based model for target ***,at the preattention stage,before getting salient regions,a fast computational approach is applied to build a saliency *** that,the focus of attention（FOA） can be quickly obtained to indicate the salient ***,at the attention stage,under the FOA guidance,the high-level visual features of the region of interest are extracted in ***,at the post-attention stage,by integrating these parallel and independent visual attributes,a decision-template based classifier fusion strategy is proposed to discriminate the task-related targets from the other extracted salient *** comparison,experiments on ship detection are done for validating the effectiveness and feasibility of the proposed model.

关键词： target detection visual attention salient region classifier fusion.

On Fault Tolerance of 3-Dimensional Mesh Networks

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Journal of Computer Science & Technology 2004年第2期19卷 183-190页

作者： gao-CaiWang jian-ErChen Guo-JunWang CollegeofInformationScienceandEngineering CentralSouthUniversityChangsha410083P.R.China SchoolofComputerandElectricalInformation GuangxiUniversityNanning530004P.R.China DepartmentofComputerScience TexasA&MUniversityU.S.A.

In this paper, the concept of k-submesh and k-submesh connectivity fault tolerance model is proposed. And the fault tolerance of 3-D mesh networks is studied under a more realistic model in which each network node has an independent failure probability. It is first observed that if the node failure probability is fixed, then the connectivity probability of 3-D mesh networks can be arbitrarily small when the network size is sufficiently large. Thus, it is practically important for multicomputer system manufacturer to determine the upper bound for node failure probability when the probability of network connectivity and the network size are given. A novel technique is developed to formally derive lower bounds on the connectivity probability for 3-D mesh networks. The study shows that 3-D mesh networks of practical size can tolerate a large number of faulty nodes thus are reliable enough for multicomputer systems. A number of advantages of 3-D mesh networks over other popular network topologies are given. Compared to 2-D mesh networks, 3-D mesh networks are much stronger in tolerating faulty nodes, while for practical network size, the fault tolerance of 3-D mesh networks is comparable with that of hypercube networks but enjoys much lower node degree.

关键词： interconnection network 3-D mesh network fault tolerance parallel processing

Experimental analyses on phase transitions in compiling satisfiability problems

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Science China(Information Sciences) 2015年第3期58卷 80-90页

作者： gao jian WANG jianan YIN MingHao College of Information Science and Technology Dalian Maritime University College of Computer Science Northeast Normal University

In the past decade,a kind of well-known phenomena in many complex combinatorial problems such as satisfiability problem,called phase transition,have been widely *** this paper,the phase transition phenomena are investigated during compiling k-satisfiability problems into tractable languages with empirical *** binary decision diagram and deterministic-decomposable negation normal form are selected as the tractable target languages for the *** intensive experiments,it can be concluded that an easy–hard–easy pattern exists during the compilations,which is only related to the ratio of the number of clauses to that of variables if we set k to a fixed value,rather than to the target ***,it can be concluded that the space exhausted during the compilations grows exponentially with the number of variables growing,whereas there is also a phase transition separating the polynomial-increment region from the exponential-increment ***,it can be observed that there is a phase transition of prime implicants around peak points of the easy–hard–easy pattern and the ratios of random instances whose average lengths of prime implicants are larger than the threshold 0.5 change *** these analyses,it can be concluded that prime implicant length and solution interchangeability are crucial impacts on sizes of compilation results.

关键词： phase transition knowledge compilation random k-SAT prime implicants easy–hard–easy pattern

Stratospheric Precursor of Non-Uniform Variation in Early Spring Surface Temperature over Eurasia

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Journal of Meteorological Research 2017年第2期31卷 389-396页

作者： fei LI Huijun WANG Yongqi gao Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Nanjing 210044 China Nansen Environmental and-Remote Sensing Centre and Bjerknes CentrejCor Climate Research Bergen N-5006 Norway

The stratospheric influences on the non-uniform variation in early spring（March–April,MA）surface temperature over Eurasia is investigated based on the ERA-Interim,NCEP-1,and NCEP-2 reanalysis data for the period1980–2016.A lead–lag correlation is found between preceding winter（December–February,DJF）stratospheric polar vortex displacements（SPVD）and the MA west–east seesaw pattern in surface temperature over *** analysis reveals that the East Asian jet stream may act as a bridge linking DJF SPVD and MA surface temperature over Eurasia.A positive change in SPVD is associated with a decelerated polar jet stream and an accelerated East Asian jet stream in the troposphere in *** East Asian jet stream signal can persist into *** a result,anomalous southerly/northerly winds prevail over western/eastern Eurasia,accounting for the west–east surface temperature seesaw over Eurasia.

关键词： stratospheric polar vortex displacement Eurasian surface temperature East Asian jet stream

Mechanochemical reactions of GaN-Al_(2)O_(3) interface at the nanoasperity contact:Roles of crystallographic polarity and ambient humidity

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Friction 2022年第7期10卷 1005-1018页

作者： jian GUO jian gao Chen XIAO Lei CHEN Linmao QIAN School of Mechanical Engineering University of South ChinaHengyang 421001China Tribology Research Institute State Key Laboratory of Traction PowerSouthwest Jiaotong UniversityChengdu 610031China Advanced Research Center for Nanolithography(ARCNL) Science Park 106Amsterdam 1098XGthe Netherlands Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province Southwest Jiaotong UniversityChengdu 610031China

Mechanochemical reactions of the GaN-Al_(2)O_(3) interface offer a novel principle for scientific and technological merits in the micro-/nano-scale ultra-precision surface *** this work,the mechanochemical reactions on Ga-and N-faced GaN surfaces rubbed by the Al_(2)O_(3) nanoasperity as a function of the environmental humidity were *** results indicate that the N-face exhibits much stronger mechanochemical removal over the relative humidity range of 20%-80%than the *** water molecules in environmental conditions significantly promotes the interfacial mechanochemical reactions and hence accelerates the atomic attrition on *** hypothesized mechanism of the selective water-involved mechanochemical removal is associated with the dangling bond configuration,which affects the mechanically-stimulated chemical reactions via altering the activation energy barrier to form the bonding bridge across the sliding *** findings can enrich the understanding of the underlying mechanism of mechanochemical reactions at GaN-Al_(2)O_(3) interface and a broad cognition for regulating the mechanochemical reactions widely existing in scientific and engineering applications.

关键词： crystallographic polarity ambient humidity mechanochemical removal GaN-Al_(2)O_(3)interface

Minimum best success probability by classical strategies for quantum pseudo-telepathy

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1244-1249页

作者： gao fei FANG Wei WEN QiaoYan State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

Quantum pseudo-telepathy(QPT)is a new type of game where the quantum team can win with certainty while the classical one *** means the advantages of quantum participants over classical ones in ***,there has been no systematic and formal analysis on the QPT game *** we present the formal description of the QPT game and the definition of the most simplified *** on the above definitions,we simplify a famous QPT game,*** Cabllo ***,according to some instances,we analyze the minimum best success probability by classical strategies of the two-player QPT,which reflects the advantage of the quantum ***,we prove the best success probability by classical strategies for the most simplified QPT is totally related to the number of all possible question combinations.

关键词： quantum game pseudo-telepathy quantum strategy