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China Foundry 2022年第6期19卷 544-550页

作者： Tian-yu liu Kun Shi Jun Zhao Shi-bing liu Hong-yu liu Bo-liang liu Xin-min Mei Zhao-sheng Ning Xiao-ming Chen State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang Research Institute of Foundry Co.Ltd.Shenyang 110022China

High-entropy alloys(HEAs)are based on solid solutions which characterized by chemical short-range ordering(CSRO),but there is no accurate structural tool to address CSRO characteristic,which obstacles precise composition design for *** this study,based on the cluster-plus-glue-atoms model,the composition law of Al-TMs(TMs,transition metals)HEAs with BCC and FCC structures was *** BCC structure,with five elements in equi-atomic ratio,the composition formula of Al-TMs HEAs can be expressed by a cluster formula[Al-M_(14)]Al_(3),and in non equi-atomic ratio can be expressed by[Al-M_(14)]Al,where M is the average atom of the *** in FCC structure,both Al-TMs HEAs with five elements in equiatomic and non equi-atomic ratios can be expressed by a cluster formula[Al-M_(12)]*** confirm the effectiveness of cluster formula for Al-TMs,two alloys were designed,[Al-Ti_(4)V_(3)Nb_(4)Mo_(3)]Mo and[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]*** show that the[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]Al alloy has both higher strength and higher plastic deformation at room ***,[Al-Ti_(3)V_(3)Nb_(4)Mo_(4)]Al alloy shows slower soften effect at 800℃,contributed to its higher *** substituting Ta for some of Mo,the strength of[Al-Ti_(3)V_(3)Nb_(4)Mo_(3)Ta]Al at room temperature and high temperature drastically decreases,suggesting that Ta element deteriorates the properties of Al-TMs alloys.

关键词： Al-TMs high-entropy alloys composition design short-range order cluster-plus-glue-atom model

The sedimentary facies and dynamic environment of the Diaokou lobe in the modern Huanghe River Delta of China

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Acta Oceanologica Sinica 2018年第11期37卷 40-52页

作者： GAO Wei liu Shihao liu Jie XU Yuanqin LI Ping Key Laboratory of Marine Sedimentology and Environmental Geology The First Institute of Oceanography State Oceanic Administration Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology (Qingdao) Research Center for Islands and Coastal Zone The First Institute of Oceanography State Oceanic Administration

The Huanghe River captures the Diaokou River in 1964 and forms a deltaic lobe in the subsequent 12 a. The progradational process of the Diaokou lobe is in associated with complicated evolution of riverine sheet flooding, merging, and swinging. On the basis of 11 borehole cores and 210 km high resolution seismic reflection data set, the sedimentary sequence and dynamic environment of the Diaokou lobe Cone subdelta lobe of the modern Huanghe River Delta） are studied. The stratigraphy of the lobe is characterized by an upward-coarsening ternary structure and forms a progradational deltaic clinoform. Totally six seismic surfaces are identifiable in seismic profiles, bounded six seismic units （SUs）. These SUs correspond to six depositional units （DUs） in the borehole cores, and among them, SUs 4-6 （DUs D to F） consist of the modern Diaokou lobe. Lithological and seismic evidences indicate that the delta plain part of the Diaokou lobe is comprised primarily by fluvial lag sediments together with sediments from sidebanks, overbanks, fluvial flood plains and levees, while the delta front part is a combination of river mouth bar sands （majority） and distal bar and deltaic margin sediments （minority）. As a result of the high sedimentation rate and weak hydrodynamic regime in the Huanghe River Delta, the sediments in the delta front are dominated by fine-grained materials. The grain size analysis indicates the Huanghe River hyperpycnal-concentrated flow shows the suspension, transportation and sedimentation characteristics of gravity flow, and the sediment transportation is primarily dominated by graded suspension, while uniform suspension and hydrostatic suspension are also observed in places. The strength of the hydrodynamic regime weakens gradually offshore from riverbed, river mouth bar, sidebank, distal bar subfacies to delta lateral margin and flooding plain subfacies.

关键词： modern Huanghe River Delta sedimentary facies sediment dynamics grain size

Processing Constrained K Closest Pairs Query in Spatial Databases

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 543-546页

作者： liu Xiaofeng liu Yunsheng XIAO Yingyuan College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074Hubei China

In this paper, constrained K closest pairs query is introduced, wbich retrieves the K closest pairs satisfying the given spatial constraint from two datasets. For data sets indexed by R trees in spatial databases, three algorithms are presented for answering this kind of query. Among of them, two-phase Range＋Join and Join＋Range algorithms adopt the strategy that changes the execution order of range and closest pairs queries, and constrained heap-based algorithm utilizes extended distance functions to prune search space and minimize the pruning distance. Experimental results show that constrained heap-base algorithm has better applicability and performance than two-phase algorithms.

关键词： spatial databases query processing R-tree closest pairs query constrained closest pairs query

Self Organization Map for Clustering and Classification in the Ecology of Agent Organizations

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Journal of Central South University 2000年第1期12卷 53-56页

作者： Dimuthu Chandana Kelegama liu Li-hua liu Jian-qin College of Information Engineering Central South University of TechnologyChangsha 410083China

Development of computational agent organizations or “societies” has become the domiant computing paradigm in the arena of Distributed Artificial Intelligence, and many foreseeable future applications need agent organizations, in which diversified agents cooperate in a distributed manner, forming teams. In such scenarios, the agents would need to know each other in order to facilitate the interactions. Moreover, agents in such an environment are not statically defined in advance but they can adaptively enter and leave an organization. This begs the question of how agents locate each other in order to cooperate in achieving organizational goals. Locating agents is a quite challenging task, especially in organizations that involve a large number of agents and where the resource avaiability is intermittent. The authors explore here an approach based on self organization map (SOM) which will serve as a clustering method in the light of the knowledge gathered about various agents. The approach begins by categorizing agents using a selected set of agent properties. These categories are used to derive various ranks and a distance matrix. The SOM algorithm uses this matrix as input to obtain clusters of agents. These clusters reduce the search space, resulting in a relatively short agent search time.

关键词： clustering classification agent organizations agent societies self organizing distributed computing

Introduction to the Special Issue on Intelligent Models for Security and Resilience in Cyber Physical Systems

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Computer Modeling in Engineering & Sciences 2022年第4期131卷 23-26页

作者： Qi liu Xiaodong liu Radu Grosu Ching-Nung Yang School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China School of Computing Edinburgh Napier UniversityEdinburgh018373UK Institute of Computer Engineering Vienna University of TechnologyWien1040Austria Department of Computer Science and Information Engineering National Dong Hwa UniversityHualien97401Taiwan

Cyber Physical Systems(CPS)have been appealing in recent years as a result of the rapid emergence of unique hardware and software compositions that create smart,autonomously behaving ***-to-end procedures and new types of user-machine interaction are made possible via the *** the one hand,these CPS applications have the potential to deliver crucial services in a variety of developing application areas,including energy management,healthcare,traffic monitoring,industrial assessment and surveillance.

关键词： CPS hardware services

Perspective on Materials Genome~

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Chinese Science Bulletin 2014年第15期59卷 1619-1623页

作者： Zikui liu Department of Materials Science and Engineering The Pennsylvania State University University Park

The author’s perspective on Materials Genome is presented in this paper through several related *** thermodynamic and kinetic databases of multicomponent materials consist of Gibbs energy functions and atomic mobility of individual phases as functions of temperature,composition,and sometimes pressure,i.e.,with the individual phases based on crystal structures as the genome(building blocks)of *** is articulated that if an individual phase has its internal configurations,such as magnetic spin configurations and ferroelectric polarization,change significantly with respect to temperature,stress,and magnetic and electric fields,then those individual configurations instead should be considered as the genome of the individual ***‘‘mutation’’of an individual phase is governed by the entropy of mixing among the individual stable and metastable configurations,named as microstate configurational entropy,and responsible to anomalies in individual *** ability to tailor the properties of those individual configurations as a function of compositions is the key for the design of materials.

关键词：基因组材料动力学数据库能量函数物料流动晶体结构构型熵迁移率

Numerical Solution of Scalar Field for Nariai Case in 5D Ricci-Flat SdS Black String Space with Polynomial Approximation

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Communications in Theoretical Physics 2008年第10期50卷 889-892页

作者： WANG Chun-Xiao liu Mo-Lin liu Hong-Ya Department of Physics Fuyang Teachers College Fuyang 236041 China School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024 China

As one exact candidate of the higher dimensional black hole, the 5D Ricci-flat Schwarzsehild-de Sitter black string space presents something interesting. In this paper, we give a numerical solution to the real scalar field around the Nariai black hole by the polynomial approximation. Unlike the previous tangent approximation, this fitting function makes a perfect match in the leading intermediate region and gives a good description near both the event and the cosmological horizons. We can read from our results that the wave is close to a harmonic one with the tortoise coordinate. Furthermore, with the actual radial coordinate the waves pile up almost equally near the both horizons.

关键词： black string real scalar field Nariai black hole polynomial approximation

A full moon in another land:The Moon Bridge in the Japanese garden of the Huntington Library

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Frontiers of Architectural Research 2020年第3期9卷 556-567页

作者： Yan liu Society of Fellows in the Liberal Arts Southern University of Science and TechnolosyShenzhenChina

In 1913,a so-called Moon Bridge was built in the Japanese garden of the Huntington Library in San Marino,California,USA as a fruit of the Japonism in the Western world at that *** master carpenter was Toichiro Kawai,a Japanese immigrant from Yokohama who was originally a ship *** bridge is made of wood and shaped in the exaggerated arch form,which classifies the bridge as a"drum bridge"(Taiko-bashi)in Japanese ***,the unique structural form of this bridge,the"woven arch",is rare in building *** paper aims to explore why and how such a bridge appeared in such a place and *** this purpose,we go from the historical background to its construction history,from the concept of the designer to the detailed design *** come partly from the author’s first-hand investigation and the limited local *** most interesting discoveries were made during the detailed on-site investigation,including the fact that the bridge is designed to express the metaphor of"perfection"(full moon)through its geometrical features,and the design is based according to traditional Japanese methods.

关键词： Drum bridge Moon bridge Wooden arch bridge Woven arch bridge Building archaeology Japonism Bridge history

Effects of air damping on quality factors of different probes in tapping mode atomic force microscopy

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Chinese Physics B 2024年第9期33卷 506-519页

作者： Yu Zeng Guo-Lin liu Jin-Hao liu Zheng Wei School of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029China

The AFM probe in tapping mode is a continuous process of energy dissipation,from moving away from to intermittent contact with the sample *** present,studies regarding the energy dissipation mechanism of this continuous process have only been reported sporadically,and there are no systematic explanations or experimental verifications of the energy dissipation mechanism in each stage of the continuous *** quality factors can be used to characterize the energy dissipation in TM-AFM *** this study,the vibration model of the microcantilever beam was established,coupling the vibration and damping effects of the microcantilever *** quality factor of the vibrating microcantilever beam under damping was derived,and the air viscous damping when the probe is away from the sample and the air squeeze film damping when the probe is close to the sample were *** addition,the mechanism of the damping effects of different shapes of probes at different tip–sample distances was *** accuracy of the theoretical simplified model was verified using both experimental and simulation methods.A clearer understanding of the kinetic characteristics and damping mechanism of the TM-AFM was achieved by examining the air damping dissipation mechanism of AFM probes in the tapping mode,which was very important for improving both the quality factor and the imaging quality of the TM-AFM *** study’s research findings also provided theoretical references and experimental methods for the future study of the energy dissipation mechanism of micro-nano-electromechanical systems.

关键词： TM-AFM quality factors air viscous damping air squeeze film damping

Electric transport mechanism and magnetoresistance of La_(0.80)Sr_(0.15)Ag_(0.05)MnO_3/x(CuO)

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Rare Metals 2015年第5期34卷 329-333页

作者： Peng liu Gui-Ying Wang Qiang Mao Ning liu Zhen-Sheng Peng Anhui Key Laboratory of Spintronic and Nano-metric Materials School of Mechanics of Electronic Engineering Suzhou University School of Electrical Engineering Anhui Engineering University

The samples of La0.80Sr0.15Ag0.05MnO3/x（CuO）（x = 0, 0.05, 0.10, 0.15, 0.20） were prepared by the solid-state reaction method, and the structure of the sampies was detected by X-ray diffraction （XRD）, scanning electron microscope （SEM） equipped with energy dispersive spectroscopy （EDS）, electric transport mechanism, and magnetoresistance enhancement, and the temperature stability of magnetoresistance of the samples was studied through resistivity-temperature （ρ-T） curves, ρ-T fitted curves, and magnetoresistance-temperature （MR-T） curves. The results indicate that ρ-T data can be fitted by the formula ρ = ρ0 ＋ AT^2 very well, and the electric transport mechanism of all the samples in metal-like area is the scattering of single magneton upon spin electron; the magnetoresistance of composite samples is far larger than that of the original material, and the MR peak value of the sample with x = 0.20 is nearly 4 times as large as that of the sample with x = 0; composite samples have comparatively good temperature stability of magnetoresistance in the temperature range of 200-260 K, and the magnetoresistance of the sample with x = 0.15 almost does not change with temperature and keeps at （5.03 ± 0.20） % in the temperature range of 210-260 K.

关键词： Temperature stability of magnetoresistance Magnetoresistance enhancement Electric transport mechanism Two-phase composite