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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 t

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

Geometrical transition properties of vortex cavitation and associated flow-choking characteristics in poppet valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 455-469页

作者： liang LU Zhongdong liang Yuming LIU Zhipeng WANG Shohei RYU School of Mechanical Engineering Tongji UniversityShanghai 201804China Frontiers Science Center for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China Technical Research Laboratory Hitachi Construction Machinery Co.Ltd.Tsuchiura 300-0013Japan

Poppet valves have become increasingly significant in ensuring precise digital flow rate and pressure control in hydraulic systems,necessitating a more profound understanding of the geometrical properties of cavitation in them,as well as associated flow-choking *** a comparative analysis with experimentally observed cavity images,we found that large eddy simulation(LES)turbulence modeling effectively replicates the geometrical properties of cavitation in these *** analysis demonstrated that cavitation is generated from vortices that result from the interaction between the notch contracta flow and the surrounding fluid *** in the internal or external vena contracta conditions result in fixed or discrete cavities,and the length-to-diameter ratio serves as a measure of the transition between internal and external vena contracta flow *** study establishes a threshold length-to-diameter ratio of approximately 2 for the tested poppet *** specifically,in notch structures with a smaller valve opening,longer sealing length,and smaller throttling angle(corresponding to a larger length-to-diameter ratio),the liquid-to-vapor transfer process is more evident than that in the reverse direction.A long-standing vapor cavity becomes fixed inside the notch,leading to a more pronounced flow-choking *** contrast,for structures with a smaller length-to-diameter ratio,the cavitation process for discrete vapor cavities is more complete,ensuring fluid flow continuity and significantly reducing the occurrence of the flow-choking phenomenon.

关键词： Poppet valves Vena contracta Vortex flow Vapor cavity Flow-choking

Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

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Rare Metals 2024年第6期43卷 2832-2841页

作者： Yan Jiang liang-liang Wei Jian He Hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(SC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the SC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) Superalloy

Review and comparison of methods and benchmarks for automatic modal identification based on stabilization diagram

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 209-224页

作者： Min He Peng liang Jiuxian Liu Zhiqiang liang School of Architecture and Civil Engineering Xi'an University of Science and TechnologyXi'an 710064China School of Highway Chang'an UniversityXi'an 710064China

Automatic modal identification via automatically interpreting the stabilization diagram provides key technique in bridge structural health *** paper reviews the progress in the area of automatic modal identification based on interpreting the stabilization *** whole identification process is divided into four steps from establishing the stabilization diagram to removing the outliers in the identification *** criteria and algorithms used in each step in the existing studies are carefully summarized and *** between typical methods in cleaning and interpreting the stabilization diagram are also *** structure benchmarks used in the existing studies to validate the proposed automatic modal identification methods are also *** on the review and comparison,the specific ratio method for cleaning the stabilization diagram,the hierarchical clustering method for interpreting the stabilization diagram and the adjusted boxplot for removing the outliers in the identification results are the most suitable methods for each *** key point of automatic modal identification based on interpreting the stabilization diagram has also discussed,and it is recommended to pay more attention to cleaning the stabilization *** study about automatic modal identification under situation with very few sensors deployed should be more *** review aims to help researchers and practitioners in implementing existing automatic modal identification algorithms effectively and developing more suitable and practical methods for civil engineering structures in the future.

关键词： Bridge structural health monitoring Automatic modal identification Stabilization diagram Eriteria and methods Real structure benchmarks

有机氟共聚改性聚对苯二甲酸乙二醇酯的合成及表面疏水性能

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高分子材料科学与工程 2017年第2期33卷 6-10页

作者：石慧梁倩倩江涌李绍龙唐安斌西南科技大学材料科学与工程学院四川绵阳621000 四川东材科技集团股份有限公司(国家绝缘材料工程技术研究中心) 四川绵阳621000

以2,2,3,3,4,4,5,5-八氟-1,6-己二醇(OFHD)作为有机氟单体,通过共聚反应制备了不同氟含量的有机氟共聚改性聚对苯二甲酸乙二醇酯(FPETs)。采用核磁共振氢谱和碳谱对其进行了表征,通过差示扫描量热分析、热重测试发现氟改性未对聚酯的热... 详细信息

以2,2,3,3,4,4,5,5-八氟-1,6-己二醇(OFHD)作为有机氟单体,通过共聚反应制备了不同氟含量的有机氟共聚改性聚对苯二甲酸乙二醇酯(FPETs)。采用核磁共振氢谱和碳谱对其进行了表征,通过差示扫描量热分析、热重测试发现氟改性未对聚酯的热性能造成影响。随着OFHD添加量的增加,X射线光电子能谱测试的FPET膜表面氟含量从0增加到1.22%时,相应的水静态接触角从76.56°增加到116.23°,原子力显微镜下能观察到较为明显的微纳米粗糙结构。

关键词：聚对苯二甲酸乙二醇酯氟改性 2,2,3,3,4,4,5,5-八氟-1,6-己二醇疏水

Time-domain Differential Protection Based on Operating and Restraining Trajectory Indices for Lines Connecting Battery Storage Energy Stations

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1074-1086页

作者： Yingyu liang Cunyue Pan School of Mechanical and Electrical Engineering China University of Mining and Technology(Beijing)BeijingChina

Battery energy storage stations(BESSs)pose sever-al challenges for both phasor-based differential protection and the newly-proposed time-domain differential *** challenges include low sensitivity and even ***,the negative impact of various nonideal conditions,including current transformer(CT)saturation,errors,and outliers,on the security of differential protection remains an important *** by the aforementioned issues,this study ac-counts for the trajectory distribution discrepancy on Cartesian plane under various conditions and proposes a time-domain dif-ferential protection *** this paper,the trajectory formed by operating and restraining current samples is ***,after considering different operating states,the fault severity levels,and nonideal conditions,the variances in trajectory distribution between internal and external faults are extensively *** this basis,the Cartesian plane is divided into operating,uncertainty,and restraining ***-ther,the operating and restraining trajectory indices are meticu-lously designed and a protection criterion based on these indi-ces is formed to accurately separate internal faults from other events,unaffected by CT saturation,errors,and *** exceptional performance of the proposed protection method is extensively validated through PSCAD simulations and a hard-ware-in-the-loop testing *** the dependability,sensitivity,and security,the proposed protection method outper-forms three state-of-the-art differential protection methods.

关键词： Battery energy storage station time-domain differential protection operating trajectory index(OTI) restraining trajectory index(RTI)

Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system

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Petroleum Science 2024年第2期21卷 1305-1319页

作者： Nai-liang Li Bin Chen School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop.

关键词： Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging Correlation

Securing offshore resources development: A mathematical investigation into gas leakage in long-distance flexible pipes

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Petroleum Science 2024年第4期21卷 2734-2744页

作者： Xiang-An Lu liang-liang Jiang Jian-Sheng Zhang Min-Gui Wang Guangling College of Yangzhou University Department of Chemical and Petroleum Engineering University of Calgary Department of Energy and Power Engineering Tsinghua University

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development. Under high pressure conditions, small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space, incurring annular pressure build-up and/or production of acidic environment, which poses serious challenges to the structure and integrity of the flexible pipes. Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature, annular structure, external temperature. In a long-distance gas flexible pipe, moreover, gas permeation exhibits non-uniform features, and the gas permeated into the annular space flows along the metal gap. To assess the complex gas transport behavior in long-distance gas flexible pipes, a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes, the diffusion of gas in the inner liner, and the gas seepage in the annular space under varying permeable properties of the annulus. In addition, the effect of a variable temperature is accounted. A numerical calculation method is accordingly constructed to solve the coupling mathematical equations. The annular permeability was shown to significantly influence the distribution of annular pressure. As permeability increases, the annular pressure tends to become more uniform, and the annular pressure at the wellhead rises more rapidly. After annular pressure relief followed by shut-in, the pressure increase follows a convex function. By simulating the pressure recovery pattern after pressure relief and comparing it with test results, we deduce that the annular permeability lies between 123 and 512 m D. The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources.

关键词： Offshore resources development Transport security Long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation

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全球变化下菌根真菌的作用及其作用机制

生态学报 2014年第21期34卷 6039-6048页

作者：梁倩倩李敏刘润进郭绍霞青岛农业大学菌根生物技术研究所青岛266109 青岛农业大学园林与林学院青岛266109

全球气候、环境、经济与社会的发展变化,对环境与资源造成严重挑战和新的发展机遇。菌根真菌是陆地生态系统中的重要生物组份,占据不可替代的重要地位,充当调控生态系统稳定和保持可持续发展的多重角色。分析了全球变化对菌根真菌的影响... 详细信息

全球气候、环境、经济与社会的发展变化,对环境与资源造成严重挑战和新的发展机遇。菌根真菌是陆地生态系统中的重要生物组份,占据不可替代的重要地位,充当调控生态系统稳定和保持可持续发展的多重角色。分析了全球变化对菌根真菌的影响,探讨了全球变化下菌根真菌的地位、角色和作用,以及菌根真菌应对全球变化的可能作用机制,旨在为加强全面应对全球变化提供新的思路和途径。

关键词：菌根菌根真菌丛枝菌根外生菌根全球变化