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China to the West:Stop Meddling

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Beijing Review 2016年第20期59卷 18-19页

作者： liu xiaoming

The issue of the South China Sea is being ramped up by those in the United States and the UK who accuse China of causing tension in the region. They proclaim theprinciple of free navigation and overflight but in reali... 详细信息

关键词：中国南海西方英国人

Existence and Uniqueness Results for a Fully Third-Order Boundary Value Problem

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Advances in Pure Mathematics 2023年第8期13卷 495-503页

作者： xiaoming liu Yongxiang Li Department of Mathematics Northwest Normal University Lanzhou China

The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have studied the boundary value problems of the complete third-order differential equations u′′′(t) = f (t,u(t),u′(t),u′′(t)). In this paper, we discuss the existence and uniqueness of solutions and positive solutions of the fully third-order ordinary differential equation on [0,1] with the boundary condition u(0) = u′(1) = u′′(1) = 0. Under some inequality conditions on nonlinearity f some new existence and uniqueness results of solutions and positive solutions are obtained.

关键词： Fully Third-Order BVP Solution Positive Solution Existence and Uniqueness Inequality Conditions

Fast Cycle Structure Detection for Power Grids Based on Graph Computing

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2204-2213页

作者： Xinqiao Wang Kewen liu Weijiang Lu Ting Zhao Baohua Zhao xiaoming liu the Computing&Application Technology Research Division Global Energy Interconnection Research InstituteBeijing 102209China

The cycle structure in a power grid may lower the stability of the network;thus,it is of great significance to accu-rately and timely detect cycles in power grid ***,detecting possible cycles in a large-scale network can be highly time consuming and computationally *** addition,since the power grid's topology changes over time,cycles can appear and disappear,and it can be difficult to monitor them in real *** traditional computing systems,cycle detection requires considerable computational resources,making real-time cycle detection in large-scale power grids an impossible *** computing has shown excellent performance in many areas and has solved many practical graph-related problems,such as power flow calculation and state *** this article,a cycle detection method,the Paton method,is implemented and optimized on a graph computing *** cases are used to test its performance in an actual power grid topology *** results show that the graph computing-based Paton method reduces the time consumption by at least 60%compared to that of other methods.

关键词： Cycle detection graph computing power grid distribution grid

Zircon and Monazite Ages Constraints on Devonian Magmatism and Granulite-Facies Metamorphism in the Southern Qaidam Block:Implications for Evolution of Proto-and Paleo-Tethys in East Asia

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Journal of Earth Science 2018年第5期29卷 1132-1150页

作者： Jin Ba Lu Zhang Chuan He Neng-Song Chen Timothy M.Kusky Qinyan Wang Yusheng Wan xiaoming liu School of Earth Sciences China University of GeosciencesWuhan 430074China College of Earth Science Chengdu University of TechnologyChengdu 610059China Sichuan Institute of Geological Survey Chengdu 610081China Center for Global Tectonics China University of GeosciencesWuhan 430074China Beijing SHRIMP Center Beijing 100037China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

High-temperature magma generation process and granulite-facies metamorphism can provide important information about mantle-crustal interaction and tectonic evolution. The strongly peralu- minous monzonite pluton, the Jinshuikou cordierite granite on the southern margin of the Qaidam Block, can provide important information about the mantle-crustal interaction and constraints on tectonic tran- sition from Proto-Tethys to Paleo-Tethys. This pluton develops enclaves of mafic granulite, amphibolite and quartzofeldspathic rocks, and is cut by massive monzonitic leuco-granite veins. Zircon and monazite U-Pb dating for the cordierite granite, the granulite enclaves and a massive monzonitic leuco-granite vein reveal that the cordierite granitic magma was generated from Mesoproterozoic continental crust with protolith derived from a provenanee that was composed of 〉2.8 Ga old recycled crustal materials and re- corded a -1.7 Ga magmatic event. The continental crust underwent low-pressure granulite-facies metamorphism at -380 Ma ago, whereas the cordierite granite magmas was generated and emplaced during 380 Ma, followed by intrusion of the massive monzonitic leuco-granite vein at circa 370-330 Ma. These data suggest that after the final closure of Proto-Tethys Ocean spreading along the southern Qaidam Block at -420 Ma, break-off of the subducted slab or delamination of the lower crustal base and upwelling of the asthenospheric mantle beneath the southern Qaidam Block occurred before the Mid-Devonian, and that the initiation of the Paleo-Tethys tectonics might initiate near the end of Early-Carboniferous in the East Kunlun-Qaidam region, East Asia.

关键词： zircon and monazite U-Pb geochronology cordierite peraluminous granite low pressure granulite Proto- and Paleo-Tethys evolution East Kunlun-Qaidam.

Sedimentary fill history of the Huicheng Basin in the West Qinling Mountains and associated constraints on Mesozoic intracontinental tectonic evolution

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Science China Earth Sciences 2013年第5期56卷 1639-1653页

作者： LI Wei DONG YunPeng GUO AnLin liu xiaoming liu YiQun ZHA XianFeng ZHANG KuaiLe State Key Laboratory of Continental Dynamics Department of GeologyNorthwest University Xi'an Center of Geological Survey China Geological Survey

The Qinling Orogenic Belt is divided commonly by the Fengxian-Taibai strike-slip shear zone and the Huicheng Basin into the East and West Qinling mountains, which show significant geological differences after the Indosinian orogeny. The Fengxian-Taibai fault zone and the Meso-Cenozoic Huicheng Basin, situated at the boundary of the East and West Qinling, provide a natural laboratory for tectonic analysis and sedimentological study of intracontinental tectonic evolution of the Qin- ling Orogenic Belt. In order to explain the dynamic development of the Huicheng Basin and elucidate its post-orogenic tecton- ic evolution at the junction of the East and West Qinling, we studied the geometry and kinematics of fault zones between the blocks of West Qinling, as well as the sedimentary fill history of the Huicheng Basin. First, we found that after the collisional orogeny in the Late Triassic, post-orogenic extensional collapse occurred in the Early and Middle Jurassic within the Qinling Orogenic Belt, resulting in a series of rift basins. Second, in the Late Jurassic and Early Cretaceous, a NE-SW compressive stress field caused large-scale sinistral strike-slip faults in the Qinling Orogenic Belt, causing intracontinental escape tectonics at the junction of the East and West Qinling, including eastward finite escape of the East Qinling micro-plate and southwest lateral escape of the Bikou Terrane. Meanwhile, the strike-slip-related Early Cretaceous sedimentary basin was formed with a fight-order echelon arrangement in sinistral shear zones along the southern margin of the Huicheng fault. Overall during the Mesozoic, the Huicheng Basin and surrounding areas experienced four tectonic evolutionary stages, including extensional rift basin development in the Early and Middle Jurassic, intense compressive uplift in the Late Jurassic, formation of a strike-slip extensional basin in the Early Cretaceous, and compressive uplift in the Late Cretaceous.

关键词： the Qinling Orogenic Belt the West Qinling the Huicheng Basin sedimentary filling tectonic evolution escape tectonics

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Simultaneously healing cracks and strengthening additively manufactured Co_(34)Cr_(32)Ni_(27)Al_(4)Ti_(3) high-entropy alloy by utilizing Fe-based metallic glasses as a glue

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Journal of Materials Science & Technology 2024年第12期179卷 125-137页

作者： Hao Kang Kaikai Song Leilei Li xiaoming liu Yandong Jia Gang Wang Yaocen Wang Si Lan Xin Lin Lai-Chang Zhang Chongde Cao School of Physical Science and Technology Northwestern Polytechnical UniversityXian 710072China School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209China Institute of Materials Shanghai UniversityShanghai 200444China Herbert Gleiter Institute of Nanoscience School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXian 710072China Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWestern Australia 6027Australia Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China

Solidification cracking issues during additive manufacturing(AM)severely prevent the rapid development and broad application of this *** this work,a representative Co_(34)Cr_(32)Ni_(27)Al_(4)Ti_(3) high-entropy al-loy(HEA)susceptible to crack formation was fabricated by selective laser melting(SLM).As expected,many macroscopic cracks *** crack issues were successfully solved after introducing a certain amount of Fe-based metallic glass(MG)powder as a glue during *** effect of MG addition on the formation and distribution of defects in the SLM-processed HEA was quantitatively *** an increasing mass fraction of the MG,the dominant defects transformed from cracks to lack of fusion(LOF)defects and finally ***,the MG preferred to be segregated to the boundaries of the molten ***,the coarse columnar crystals gradually transformed into equiaxed crystals in the molten pool and fine-equiaxed crystals at the edge of the molten pool,inhibiting the initiation of cracks and providing extra grain boundary ***,multiple precipitates are formed at the boundaries of cellular structures,which contribute significantly to *** to the brit-tle SLM-processed Co_(34)Cr_(32)Ni_(27)Al_(4)Ti_(3) HEA,the SLM-processed HEA composite exhibited a high ultimate tensile strength greater than 1.4 Ga and enhanced *** work demonstrates that adding Fe-based MG powders as glues into SLM-processed HEAs may be an attractive method to heal cracks and simultaneously enhance the mechanical properties of additively manufactured products.

关键词： Selective laser melting High-entropy alloys Crack healing Metallic glasses Mechanical properties

Sustainable Application of a Novel Water Cycle Using Seawater for Toilet Flushing

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Engineering 2016年第4期2卷 460-469页

作者： xiaoming liu Ji Dai Di Wu Feng Jiang Guanghao Chen Ho-Kwong Chui Mark C. M. van Loosdrecht Department of Civil and Environmental Engineering The Hong Kong University of Science and Technology Hong Kong China Water Technology Center The Hong Kong University of Science and Technology Hong Kong China Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution (Hong Kong Branch) The Hong Kong University of Science and Technology l-long Kong China School of Chemistry and Environment South China Normal University Guangzhou 510006 China Department of Biotechnology Delft University of Technology Delft2629 HZ the Netherlands

Global water security is a severe issue that threatens human health and well-being. Finding sustainable alternative water resources has become a matter of great urgency. For coastal urban areas, desalinated seawater could serve as a freshwater supply. However, since 20%-30% of the water supply is used for flushing waste from the city, seawater with simple treatment could also partly replace the use of freshwater. In this work, the freshwater saving potential and environmental impacts of the urban water system （water-wastewater closed loop） adopting seawater desalination, seawater for toilet flushing （SWTF）, or reclaimed water for toilet flushing （RWTF） are compared with those of a conventional freshwater system, through a life-cycle assessment and sensitivity analysis. The potential applications of these processes are also assessed. The results support the environmental sustainability of the SWTF approach, but its potential application depends on the coastal distance and effective population density of a city. Developed coastal cities with an effective population density exceeding 3000 ***-2 and located less than 30 km from the seashore （for the main pipe supplying seawater to the city） would benefit from applying SWTF, regardless of other impact parameters. By further applying the sulfate reduction, autotrophic denitrification, and nitrification integrated （SANI） process for wastewater treatment, the maximum distance from the seashore can be extended to 60 km. Considering that most modern urbanized cities fulfill these criteria, the next generation of water supply systems could consist of a freshwater supply coupled with a seawater supply for sustainable urban development.

关键词： Alternative water resources Seawater toilet flushing SANIUrban water system Life-cycle assessment

Efficacy and complications of inoperable malignant distal biliary obstruction treatment by metallic stents:fully covered or uncovered?

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Gastroenterology Report 2023年第1期11卷 151-158页

作者： Jiangning Gu Xiaoyi Guo Yong Sun Bin Fan Haoran Li Ting Luo Haifeng Luo Jiao liu Feng Gao Yuan Gao Guang Tan xiaoming liu Zhuo Yang Department of Endoscope General Hospital of Northern Theater CommandShenyangLiaoningP.R.China Department of Hepatobiliary Surgery The First affiliated Hospital of Dalian Medical UniversityDalianLiaoningP.R.China Department of General Surgery The First Hospital of Northwest University(Xi’an No.1 Hospital)Xi’anShaanxiP.R.China Department of Anesthesiology The First affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina

Obstructive jaundice caused by malignant distal biliary obstruction is a common clinical symptom in patients with inoperable biliary–pancreatic *** retrograde cholangiopancreatography(ERCP)-guided stent implantation is an effective treatment for obstructive *** stent drainage is more physiologic and associated with a better quality of life than external stent drainage methods such as percutaneous transhepatic gallbladder drainage or percutaneous transhepatic *** metallic stents,which may be covered and uncovered,are commonly ***,some uncertainties remain regarding the selection of metallic stents,including drainage patency time,clinical effect,stent migration,and post-operative complications such as pancreatitis,bleeding,and *** review aims to summarize the current progress and controversies surrounding the use of covered or uncovered metallic stents in inoperable common biliary obstruction via ERCP.

关键词： malignant distal biliary obstruction ERCP metallic stents USEMS CSEMS

ANALYSIS OF SLAB EDGING BY A 3-D RIGID VISCO-PLASTIC FINITE ELEMENT METHOD

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 48-52页

作者： Zhang xiaoming Jiang Zhengyi liu Xianghua Wang Guodong State Key Laboratory of Rolling Technology and Automation，Northeastern University， Shenyang 110006，China State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110006 China

3-D rigid visco-plastic finite element method (FEM) is used in the analysisof metal forming processes, including strip and plate rolling, shape rolling, slab edging, specialstrip rolling. The shifted incomplete Cholesky decomposition of the stiffness matrix with thesolution of the equations for velocity increment by the conjugate gradient method is combined. Thistechnique, termed the shifted ICCG method, is then employed to solve the slab edging problem. Theperformance of this algorithm in terms of the number of iterations, friction variation, shiftedparameter psi and the results of simulation for processing parameters are analysed. Numerical testsand application of this technique verify the efficiency and stability of the shifted ICCG method inthe analysis of slab edging.

关键词： 3-D rigid visco-plastic FEM Shifted ICCG method Slab edging Frictionvariation