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Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang Dong yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and gas reservoir geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and gas Equipment technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. the separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. the simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. the composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

hybrid vibration isolation optimization of a flexible manipulator based on neural network agent model

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Chinese journal of Aeronautics 2024年第5期37卷 482-505页

作者： yongxin ZhANg liang LI Dingguo ZhANg Wei-hsin liao Xian gUO School of Science Nanjing University of Science and TechnologyNanjing 210094China Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina

Segmented Active Constrained Layer Damping(SACLD)is an intelligent vibration-damping structure,which could be applied to the sectors of aviation,aerospace,and transportation engineering to reduce the vibration of flexible ***,machine learning technology is widely used in the engineering field because of its efficient multi-objective *** dynamic simulation of a rotational segmental flexible manipulator system is presented,in which enhanced active constrained layer damping is carried out,and the neural network model of genetic Algorithm-Back Propagation(gA-BP)algorithm is *** suppression and structural optimization of the SACLD manipulator model are studied based on vibration mode and damping *** modal responses of the SACLD manipulator model at rest and rotation are *** addition,the four model indices are optimized using the gA-BP neural network:axial incision size,axial incision position,circumferential incision size,and circumferential incision ***,the best model for vibration suppression is obtained.

关键词： Machine learning Vibration suppression Flexible manipulator Segmented active constrained layer damping Structural optimization

global existence and large-time behavior for primitive equations with the free boundary

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Science China Mathematics 2024年第10期67卷 2303-2330页

作者： hai-liang Li Chuangchuang liang School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Academy for Multidisciplinary Studies Capital Normal UniversityBeijing 100048China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

In the present paper, the primitive equations, which can be used to simulate the large-scale motion of the ocean and atmosphere, are considered in the three-dimensional domain bounded below by a fixed solid boundary and above by a free-moving boundary. the global existence and uniqueness of strong solutions are established, and the long-time convergence to the equilibrium state is shown to be either at an exponential rate for the horizontal periodic domain or at an algebraic rate for the horizontal whole space.

关键词： primitive equations the free boundary value problem global well-posedness large-time behavior

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Sufficient Conditions for Amalgamated 3-Manifolds to be ∂-Irreducible

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 161-172页

作者： Bing FANg Fengchun LEI liang liang School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina School of Mathematics Liaoning Normal UniversityDalian 116029LiaoningChina

In this paper,the authors give some sufficient conditions for an amalgamated 3-manifold along a compact connected surface F with boundary to be ∂-irreducible in terms of distances between some kinds of vertex subsets ... 详细信息

关键词： ∂-Irreducibility Irreducibility Amalgamated 3-manifold Curve complex Arc complex

towards net zero carbon buildings:Accounting the building embodied carbon and life cycle-based policy design for greater Bay Area,China

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geoscience Frontiers 2024年第3期15卷 284-297页

作者： hanwei liang Xin Bian liang Dong Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/research Center of Urban Sustainable Development/School of geographical Sciences Nanjing University of Information Science&Technology(NUIST)Nanjing 210044China Department of Architecture and Civil Engineering Chalmers University of TechnologySE-41296 GothenburgSweden Shenzhen research Institute(SrI) City University of Hong KongShenzhenChina Department of Public and International Affairs(PIA) City University of Hong Kong999077Hong Kong Special Administrative Region School of Energy and Environment(SEE) City University of Hong Kong999077Hong Kong Special Administrative RegionChina Centre for Public Affairs and Law City University of Hong Kong999077Hong Kong Special Administrative RegionChina

Carbon mitigation of buildings is critical to promote a net-zero *** international society has vigorously promoted‘‘Net Zero Carbon Buildings”across the globe,and accounting for building carbon emissions is critical to support this *** carbon,which represents carbon emissions from the entire lifecycle of the buildings,is fundamental for realizing the idea of zero ***,only limited studies have been conducted so far that take into account the city *** paper aimed to act as a first try to account for the embodied carbon emissions in buildings in 2020 for the guangdong-hong Kong Macao greater Bay Area in China(gBA).We integrated remote sensing techniques such as night-time light data(NLt)and building material flows analysis to calculate and spatialize the newly generated building material stocks(MS).Based on the MS data,we further applied life cycle assessment(LCA)to assess the embodied carbon in the *** results highlighted that over 163 million tons of embodied carbon in buildings of gBA are expected to be generated,from 497 million tons of newly generated building MS in *** embodied carbon in each life cycle stage is valuable for further lifecyclebased policy designs for:(i)supporting the updating of the green building certification system with consideration of the embodied carbon;(ii)promoting the green building material application and certification;and(iii)reducing the embodied carbon intensity from compact urban planning policy,such as the urban agglomeration policies in *** goal of this paper was to shed a light on reducing carbon emissions from the perspective of the entire lifecycle and promote the development of net zero carbon buildings in China and Asia-Pacific.

关键词： Net zero carbon building Embodied carbon Life cycle assessment Life cycle-based policies greater Bay area

reliability Assessment of a New general Matching Composed Network

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China Communications 2024年第2期21卷 245-257页

作者： Zhengyuan liang junbin liang guoxuan Zhong guangxi Key Laboratory of Multimedia Communications and Network technology School of ComputerElectronics and InformationGuangxi UniversityNanning 530004China jiangxi Engineering Laboratory of Iot technologies for Crop growth Ji’an 343000China

the reliability of a network is an important indicator for maintaining communication and ensuring its stable operation. therefore, the assessment of reliability in underlying interconnection networks has become an increasingly important research issue. however, at present, the reliability assessment of many interconnected networks is not yet accurate,which inevitably weakens their fault tolerance and diagnostic capabilities. to improve network reliability,researchers have proposed various methods and strategies for precise assessment. this paper introduces a novel family of interconnection networks called general matching composed networks(gMCNs), which is based on the common characteristics of network topology structure. After analyzing the topological properties of gMCNs, we establish a relationship between super connectivity and conditional diagnosability of gMCNs. Furthermore, we assess the reliability of g MCNs, and determine the conditional diagnosability of many interconnection networks.

关键词： conditional diagnosability interconnection networks network reliability super connectivity

Creep constitutive model considering nonlinear creep degradation of fractured rock

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International journal of Mining Science and technology 2024年第1期34卷 105-116页

作者： Wang Chunping Liu jianfeng Chen liang Liu jian Wang Lu liao yilin Beijing research Institute of Uranium geology Beijing 100029China CAEA Innovation Center for geological Disposal of high-Level radioactive Waste Beijing 100029China State Key Laboratory of hydraulics and Mountain river Engineering Sichuan UniversityChengdu 610065China School of Architecture and Civil Engineering Xihua UniversityChengdu 610039China

Stability analysis of underground constructions requires a model study of rock masses’ long-term performance. Creep tests under different stress conditions was conducted on intact granite and granite samples fractured at 30° and 45° angles. the experimental results indicate that the steady creep strain rates of intact and fractured rock present an exponential increase trend with the increase of stress level. A nonlinear creep model is developed based on the experimental results, in which the initial damage caused by fracture together with the damage caused by constant load have been taken into consideration. the fitting analysis results indicated that the model proposed is more accurate at identifying the full creep regions in fractured granite, especially the accelerated stage of creep deformation. the least-square fit error of the proposed creep model is significantly lower than that of Nishihara model by almost an order of magnitude. An analysis of the effects of elastic modulus, viscosity coefficient, and damage factors on fractured rock strain rate and creep strain is conducted. If no consideration is given to the effects of the damage, the proposed nonlinear creep model can degenerate into to the classical Nishihara model.

关键词： Fractured rock Damage Creep Beishan granite geological disposal

Non-interactive SM2 threshold signature scheme with identifiable abort

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Frontiers of Computer Science 2024年第1期18卷 171-185页

作者： huiqiang liang jianhua ChEN School of Mathematics and Statistics Wuhan UniversityWuhan 430072China

A threshold signature is a special digital signature in which the N-signer share the private key x and can construct a valid signature for any subset of the included t-signer,but less than t-signer cannot obtain any *** the breakthrough achievements of threshold ECDSA signature and threshold Schnorr signature,the existing threshold SM2 signature is still limited to two parties or based on the honest majority setting,there is no more effective solution for the multiparty *** make the SM2 signature have more flexible application scenarios,promote the application of the SM2 signature scheme in the blockchain system and secure cryptocurrency *** paper designs a non-interactive threshold SM2signature schemebasedon partially homomorphic encryption and zero-knowledge *** the last round requires the message input,so make our scheme non-interactive,and the pre-signing process takes 2 rounds of communication to complete after the key *** allow arbitrary threshold tgn a key update *** can achieve security with identifiable abort under the malicious majority,which means that if the signature process fails,we can find the failed *** analysis shows that the computation and communication costs of the pre-signing process grows linearly with the parties,and it is only 1/3 of the Canetti's threshold ECDSA(CCS'20).

关键词： SM2 signature secure multi-party computation threshold signature UC-secure dishonest majority

the Faber Operator Acting on BMOA, BMO-teichmüller Space and Chord-arc Curves

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2359-2387页

作者： tai liang LIU yu liang ShEN Department of Mathematics Soochow University

After reviewing grunsky operator and Faber operator acting on Dirichlet space, we discuss the boundedness of Faber operator on BMOA, a new subject which turns out to be closely related to the BMO theory of the universal teichmüller space. In particular, we show that the Faber operator acts as a bounded operator on BMOA if the symbol conformal map stays nearly to the base point in the BMO-teichmüller space. Meanwhile, we obtain several results on quasiconformal mappings, BMOteichm¨uller space and chord-arc curves as well. As by-products, this provides a complex analysis approach to the boundedness of the Cauchy integral acting on BMO functions on a chord-arc curve near to the unit circle in the BMO-teichmüller space.

关键词： 30C62 30h35 32g15 BMO BMO-teichmüller space BMOA Carleson measure Cauchy integral chord-arc curve Faber operator grunsky operator quasicircle quasiconformal mapping