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Adaptive algorithm for estimating excavation-Induced displacements using field performance data

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Underground Space 2020年第2期5卷 115-124页

作者： Haijian Fan Gangqiang kong Transportation Engineer Texas Department of TransportationUSA College of Civil and Transportation Engineering Hohai UniversityNanjingJiangsu ProvinceChina

Empirical models provide a practical way to estimate the displacements induced by ***,there are uncertainties associated with the predictions of empirical models owing to:(a)the imperfect knowledge of the model and(b)the uncertainties of the input *** uncertainties of these models can be characterized by a bias factor which is defined as the ratio of the actual displacement to the predicted *** bias factors associated with the C&O method and the KJHH model are evaluated using the Bayesian method and a database of 71 excavations in *** improve the predictions of the maximum displacement,an adaptive algorithm is proposed using field performance *** performance of the proposed algorithm is demonstrated by an example in which excavation-induced displacements are generated by finite element method in normally consolidated *** example shows that the developed algorithm can significantly improve the predictions by incorporating the field performance data.

关键词： Excavation Displacement prediction Bayesian updating Model bias

Recent progresses of NMOS and CMOS logic functions based on two-dimensional semiconductors

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Nano Research 2021年第6期14卷 1768-1783页

作者： Lingan kong Yang Chen Yuan Liu Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education School of Physics and ElectronicsHunan UniversityChangsha410082China

Metal-oxide-semiconductor field effect transistors(MOSFET)based on two-dimensional(2D)semiconductors have attracted extensive attention owing to their excellent transport properties,atomically thin geometry,and tunable *** improving the transistor performance of individual device,lots of efforts have been devoted to achieving 2D logic functions or integrated circuit towards practical *** this review,we discussed the recent progresses of 2D-based logic *** will first start with the different methods for realization of n-type metal-oxide-semiconductor(NMOS)-only(or p-type metal-oxide-semiconductor(PMOS)-only)logic ***,various device polarity control and complementary-metal-oxide-semiconductor(CMOS)approaches are summarized,including utilizing different 2D semiconductors with intrinsic complementary doping,charge transfer doping,contact engineering,and electrostatics *** will discuss the merits and drawbacks of each approach,and lastly conclude with a short perspective on the challenges and future developments of 2D logic circuit.

关键词： field effect transistors two-dimensional semiconductors logic circuit complementary-metal-oxide-semiconductor(CMOS) polarity control

Cross-Linguistic Influence in Hong kong ESL Learners' Acquisition of Conjunctions

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Fudan Journal of the Humanities and Social Sciences 2023年第4期16卷 515-539页

作者： Ming Sum kong Mary Carr Sin Wang Chong International Education Institute University of St.AndrewsKinessburn Kennedy GardensSt Andrews KY169DJUK Student Services University of DundeeDundee DD14HNUK

Language transfer is one of the most significant aspects of cross-linguistic *** can be divided into two types:positive and negative,the beneficial and det-rimental use of one language's acquired characteristics in *** study aims to investigate the L1(Chinese)influence on Hong kong ESL learners'acquisition of conjunctions and whether the use of L1 has an impact on this *** online questionnaire combining questions about students'English learning experience and a grammatical judgement task was sent to a government-funded secondary school in Hong kong and completed by 79 *** of both positive and negative transfer from Chinese to English was found by testing six conjunctions or conjunc-tion pairs:although...but,because...so,not only...but also,either...or,neither...nor,.and *** results suggest that Chinese is likely to have an impact on students'acquisition of conjunctions,and the use of Chinese in English classes can worsen negative transfer and boost positive *** degree of transfer might increase when more Chinese is used in *** alleviate the impact of Chinese transfer and to provide more effective L2 teaching,monitoring the use of L1 and regular evalua-tion might be *** can also adjust the amount of Chinese used according to the students'English proficiency level.

关键词： Cross-linguistic influence Language transfer Conjunctions Hong kong ESL learners

Additive manufacturing of high-strength Inconel 718 alloy through the addition of Ti_(2) AlC MAX particles

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Journal of Materials Science & Technology 2023年第27期158卷 180-193页

作者： Yu kong Kaiyuan Peng Haihong Huang School of Mechanical Engineering Hefei University of TechnologyHefei 230009China Key Laboratory of Green Design and Manufacturing of Mechanical Industry Hefei University of TechnologyHefei 230009China

Decreasing the content of detrimental Laves phase in additively manufactured Inconel 718 alloy is highly *** the present study,we introduce a novel approach to effectively suppress the precipitation of Laves *** ex-situ incorporation of Ti_(2) AlC MAX particles,Ti_(2) AlC/Inconel 718 composites with Ti_(2) AlC volume fractions of 5%and 10%are successfully fabricated using the directed energy deposition(DED)*** comparison to the Inconel 718 alloy,the 10 vol.%Ti_(2) AlC/Inconel 718 composite exhibits 70.9%higher yield strength,39.1%higher ultimate tensile strength,and 61.4%higher hardness.A detailed microstructure examination confirms that the detrimental Laves phase,which is abundantly present in the inter-dendritic region,is replaced by in-situ formed(Nb,Ti)(C,N)andγ’particles with average diam-eters of 1.12μm and 10 nm,*** non-equilibrium solidification process simulation,the suppression of Laves phase,in-situ formation of multi-scale precipitates,and the microstructural evolu-tion due to Ti_(2) AlC addition are illustrated at the mechanistic ***,a theoretical model of Ti_(2) AlC/Inconel 718 composite is developed to reveal its underlying strengthening *** is indi-cated that Ti_(2) AlC/Inconel 718 composites possess the capability to be a next-generation high-end nickel-based alloy.

关键词： Additive manufacturing Inconel 718 Max phase Microstructure Mechanical properties

Polymer-to-Monomers Chemically Recyclable Poly(imide-imine)Plastics with Extreme-Condition Resistance and Flame Retardancy

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Chinese Journal of Polymer Science 2024年第10期42卷 1525-1535,I0012页

作者： Zhen-Yu Wang Xiao-kong Liu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Polyimides are a family of high-tech plastics that have irreplaceable applications in the fields of aerospace,defense,and opto-electronics,but polyimides are difficult to be reprocessed and recycled at the end of their service life,resulting in a significant waste of ***,it is of great significance to develop recyclable polyimides with comparable properties to the commercial ***,we report a novel polymer-to-monomers chemically recyclable poly(imide-imine)(PtM-CR-PII)plastic,synthesized by cross-linking the amine-terminated aromatic bisimide monomer and the hexa-vanillin terminated cyclophosphazene monomer via dynamic imine *** PtM-CR-PII plastic exhibits comparable mechanical and thermal properties as well as chemical stability to the commercial *** PtM-CR-PII plastic possesses a high Young’s modulus of≈3.2 GPa and a tensile strength as high as≈108 MPa,which also exhibits high thermal stability with a glass transition temperature of≈220℃.Moreover,the PtM-CR-PII plastic exhibits outstanding waterproofness,acid/alkali-resistance,and solvent-resistance,its appearance and mechanical properties can be well maintained after long-term soaking in water,highly concentrated acid and base,and various organic ***,the cyclophosphazene moieties endow the PtM-CR-PII plastic with excellent flame *** PtM-CR-PII plastic exhibits the highest UL-94 flame-retarding rating of V-0 and a limiting oxygen index(LOI)value of 45.5%.Importantly,the PtM-CR-PII plastic can be depolymerized in an organic solvents-acid mixture medium at room temperature,allowing easy separation and recovery of both monomers in high *** recovered pure monomers can be used to regenerate new PtM-CR-PII plastics,enabling sustainable polymer-monomers-polymer circulation.

关键词： Chemical recyclability Polyimides Polyimines Dynamic imine bonds Mechanical properties Chemical stability

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Effects of temperature and stress on the creep behavior of a Ni3Al base single crystal alloy

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Progress in Natural Science:Materials International 2013年第2期23卷 205-210页

作者： Zhigang kong Shusuo Li School of Automation Beijing University of Post and Telecommunications School of Materials Science and Engineering Beihang University

The creep behavior and microstructure of a Ni3Al base single crystal alloy IC6SX with [001] orientation under the testing conditions of 760 ℃/593 MPa, 980 ℃/205 MPa, and 1100 ℃/75 MPa were investigated. The experimental results showed that Alloy IC6SX had good creep resistance and its creep resistance at elevated temperatures was similar to the second generation nickel-base single crystal alloy containing Re. TEM analysis indicated that the dislocation configuration and movement pattern were different under different temperature and stress conditions. It has been found that under the test condition of 1070 ℃/137 MPa the dislocations moved within the γ channel during the primary creep stage, and the motion of dislocations were prevented by the matrix of γ′ phase, which reduced the creep rate of the alloy. In the secondary creep stage, dislocations cut into the γ′ phase from the γ/γ′ interface. However in the third creep stage, the dislocation pileups were observed in both γ and γ′ phase, and dislocation multiplication occurred when the dislocations with different Burgers vector met and reacted each other.

关键词： Single crystal Ni3Al alloy Creep Dislocation

Fabrication of bulk Al-Co-Cr-Fe-Ni high-entropy alloy using combined cable wire arc additive manufacturing(CCW-AAM):Microstructure and mechanical properties

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Journal of Materials Science & Technology 2021年第15期74卷 136-142页

作者： Qingkai Shen Xiangdong kong Xizhang Chen College of Mechanical and Electrical Engineering Wenzhou UniversityWenzhou325000China

Additive manufacturing is a very promising manufacturing method widely used in various *** this study,for the first time,a new type of combined cable wire(CCW)with multi-element composition has been designed and developed for arc additive manufacturing(AAM)of non-equiatomic Al-Co-Cr-FeNi high-entropy *** composed of 7 filaments and 5 elements has the advantages of high deposition efficiency,self-rotation of welding arc and energy saving *** HEA walls were fabricated under pure argon gas using cold metal transfer *** observations of the developed HEA reveal(i)BCC and FCC phases,(ii)Good bonding between layers and(iii)defect-free *** developed alloy exhibits high compression strength(~2.8 GPa)coupled with high plastic strain(~42%)values(possess both strength and ductility).It has been identified that by varying the heat input via torch travel speed,the microstructure and mechanical properties of the HEA can be *** this feasibility study,it has been proved that the innovative CCW method can be used to manufacture HEAs with ***,the study highlights the advantage of the rapid cooling involved in the CCW-AAM process which gives rise to superior mechanical properties.

关键词： Combined cable wire Arc additive manufacturing High-entropy alloy Microstructure Mechanical properties

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Fixed-parameter tractability of capacitated k-facility location

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Frontiers of Computer Science 2023年第6期17卷 171-173页

作者： Xiangyan kong Zhen ZHANG School of Computer Science and Engineering Central South UniversityChangsha 410000China School of Frontier Crossover Studies Hunan University of Technology and BusinessChangsha 410205China Changsha Social Laboratory of Artificial Intelligence Changsha 410205China

1 Introduction In this paper we study the capacitated k-facility location(Capk-FL)*** instance I of the problem is specified by a set C of clients and a set F of facilities located in a metric space with distance function d,and a positive integer k,where ICI+[F|=n,each facility f eF is associated with a capacityμ(f)>0 and a facility-opening cost o(f)>0,and connecting a client c ∈ C to f incurs a client-connection cost that equals the distance from c to f.

关键词： client problem Fixed

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Majorana gets an iron twist

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National Science Review 2019年第2期6卷 196-197页

作者： Lingyuan kong Hong Ding Institute of Physics Chinese Academy of Sciences

A magical coincidence of condensedmatter physics occurred in *** February of that year,a new kind of high-Tc（26 K）superconductivity was reported in the fluorine-doped iron-basedsuperconductor（FeSC） La[O1-xFx]FeAs[1],starting the ‘Iron Age’ of *** the following April,a 3D topological insulator（TI）was verified in Bi–Sb alloy[2],triggering a worldwide wave of searching for more

关键词： ARPES Majorana gets an iron twist MBS