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A Secure and Efficient Handover Authentication and Key Management Protocol for 5G Networks

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Journal of Communications and Information Networks 2020年第1期5卷 40-49页

作者： Jiaqi Huang yi qian Department of Electrical and Computer Engineering University of Nebraska-Lincoln1110 S 67th StreetOmahaNE 68182USA

As a major component of thefifth-generation(5G)wireless networks,network densification greatly increases the network capacity by adding more cell sites into the ***,the densified network increases the handover frequency of fast-moving mobile users,like ***,seamless handover with security provision is highly desirable in 5G *** third generation partnership project(3GPP)has been working on standardization of the handover procedure in 5G networks to meet the stringent efficiency and security ***,the existing handover authentication process in 5G networks has securityflaws,*** to replay and de-synchronization attacks,and cannot provide perfect forward *** this paper,we propose a secure and efficient handover authentication and key management protocol utilizing the Chinese remainder *** proposed scheme preserves the majority part of the original 5G system architecture defined by 3GPP,thus can be easily implemented in *** security analysis based on BAN-logic shows that the proposed scheme achieves secure mutual authentication and can remedy some security flaws in original 5G handover *** analysis shows that the proposed protocol has lower communication overhead and computation overhead compared with other handover authentication schemes.

关键词： 5G wireless network handover authentication key management security

Toxic effect of sodium perfluorononyloxy-benzenesulfonate on Pseudomonas stutzeri in aerobic denitrification,cell structure and gene expression

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Frontiers of Environmental Science & Engineering 2021年第5期15卷 247-256页

作者： yi qian Weichuan Qiao Yunhao Zhang Department of Environmental Engineering College of Biology and the EnvironmentNanjing Forestry UniversityNanjing210037China

The toxicities of sodium perfluorononyloxy-benzenesulfonate(OBS)to animals and plants are similar to those of perfluorooctane ***,the mechanism of its toxicity to aerobic denitrifying bacteria is still *** the present study,the ecotoxicity of OBS on an aerobic denitrifying strain,Pseudomonas stutzeri,was *** results showed that a dosage of OBS clearly affected the growth and aerobic denitrification of *** compared with an unamended control,the degradation efficiency of the total nitrogen decreased by 30.13%during exposure to 200 mg/L of OBS,and the complete degradation time of nitrate-nitrogen was delayed by 4 *** lactate dehydrogenase and superoxide dismutase produced by the bacteria increased with the concentration of OBS,and reactive oxygen species were also detected by confocal laser scanning microscope *** electron microscope imaging revealed chromosome deformation of the cells and damage to cell content;moreover,outer membrane vesicles were secreted from the bacteria,which was the important detoxification mechanism of *** to *** of the genes involved in aerobic nitrification and oxidative stress were also changed under OBS stress,which further confirmed the toxicity of OBS to P *** study reveals the environmental exposure risk of OBS from the perspective of microorganisms.

关键词： Sodium perfluorononyloxy-benzenesulfonate Aerobic denitrification Pseudomonas stutzeri Ecotoxicity ROS

Sustainable Management of Water Resources

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Engineering 2016年第1期2卷 23-25页

作者： yi qian School of Environment Tsinghua University Beijing 100084 China

Water is a very valuable resource, sustaining human life, pro- duction processes, and ecosystems; thus, particular attention should be paid to the management of water resources. China is now facing a serious water crisis, including water shortages, flooding, and water pollution, due to both natural and artificial causes. This water crisis has threatened human health and eco- nomic development.

关键词：水资源短缺可持续管理生态系统生产过程人为原因经济发展水危机水污染

Liutex(vorex)cores in transitional boundary layer with spanwise-wall oscillation

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Journal of Hydrodynamics 2019年第6期31卷 1178-1189页

作者： yi-qian Wang Chaoqun Liu School of Mathematical Science Soochow UniversitySuzhou 215006China Department of Mathematics University of Texas at ArlingtonArlington 76019USA

The vortex core detection method based on the Liutex vector is utilized to investigate the alternation of vortical structures on a boundary layer transition subjected to spanwise-wall *** with iso-surface based methods,the Liutex core line method is shown to be precise,free of threshold and capable to capture both strong and weak vortices ***-Schlichting(T-S)waves in the linear growth region,A-and hairpin vortices in the transition region and twisted vortices in the turbulent region are all well captured by Liutex core *** cyclic wall movement accelerates the transition process while reducing the turbulent drag by 21.8%with selected *** the wall oscillation case,the development from T・S wave to Avortex is advanced about one T・S wave length in the stream wise *** the transition region,the A-vortex and legs of hairpin vortex are shortened in the wall oscillation case,and the symmetry of the vortical structures is lost in the late transition region since the introduction of asymmetry disturbances by the cyclic wall *** of weak vortices at the edge of boundary layer are found in the turbulent section which is often omitted by iso-surface based vortex identification ***,it is demonstrated that for the transitional boundary layer the Liutex core line method provides a systematic and thresholdvortex definition,which could serve as a powerful tool to understand and guide flow control.

关键词： Liutex vector Liutex core line boundary layer transition spanwise-wall oscillation

A letter for objective Liutex

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Journal of Hydrodynamics 2022年第5期34卷 965-969页

作者： yifei Yu yi-qian Wang Chaoqun Liu Department of Mathematics University of Texas at ArlingtonArlingtonTexas76019USA School of Mathematical Science Soochow UniversitySuzhou215006China

Vortex structures,detected by the existing popular vortex identification methods,of the same case are generally different if the results are measured by different observers,who are moving with different coordinate *** coordinate systems can be inertial or *** invariance can solve the moving observer problems in different inertial coordinate systems.A variable is invariant under Galilean transformation is called Galilean *** invariant vortex identification methods can provide invariant vortex structures based on different inertial ***,for some situations,the observers are non-inertial,e.g.,the observer is sitting on an aircraft which is accelerating or *** such a situation,it requires to use an objective *** represents a property that one variable is not observer-dependent(the observer’s motion can be either inertial or non-inertial).A strategy based on a zero-vorticity(measured in inertial frame)reference point is proposed in this letter to find the objective vortex *** is chosen as the vortex indicator and two numerical examples are used to test the proposed *** results show that the strategy is effective.

关键词： Objective Liutex vortex structure Galilean invariance

Modeling and Computing of Fractional Convection Equation

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Communications on Applied Mathematics and Computation 2019年第4期1卷 565-595页

作者： Changpin Li qian yi Department of Mathematics Shanghai UniversityShanghai 200444China

In this paper,we derive the fractional convection(or advection)equations(FCEs)(or FAEs)to model anomalous convection *** using a continuous time random walk(CTRW)with power-law jump length distributions,we formulate the FCEs depicted by Riesz derivatives with order in(0,1).The numerical methods for fractional convection operators characterized by Riesz derivatives with order lying in(0,1)are constructed *** the numerical approximations to FCEs are studied in *** adopting the implicit Crank-Nicolson method and the explicit Lax-WendrofT method in time,and the secondorder numerical method to the Riesz derivative in space,we,respectively,obtain the unconditionally stable numerical scheme and the conditionally stable numerical one for the FCE with second-order convergence both in time and in *** accuracy and efficiency of the derived methods are verified by numerical *** transport performance characterized by the derived fractional convection equation is also displayed through numerical simulations.

关键词： Continuous time random walk Fractional convection equation Power-law distribution Riesz derivative

Repairing of rutin to the toxicity of combined F-53B and chromium pollution on the biofilm formed by Pseudomonas aeruginosa

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Journal of Environmental Sciences 2023年第5期127卷 158-168页

作者： Yunhao Zhang yi qian Ming Zhang Weichuan Qiao Department of Environmental Engineering College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China

The wastewater discharge from the process of chrome plating,which contains 6:2 chlorinated polyfluorinated ether sulfonate(F-53B)and chromium(Cr),may be toxic to *** this study we found that the biofilm formed by Pseudomonas aeruginosa PAO1 was inhibited by exposure to a combination of F-53B and Cr(VI).The combined pollution damaged the cell membranes and the structure of the biofilm,and inhibited the production of the Pseudomonas quinolone-based signal,which affected biofilm ***,the secretion of extracellular polymeric substances decreased as a result of this combined *** to F-53B and Cr(VI)individually or in combination could induce the excessive accumulation of intracellular reactive oxygen species(ROS),and the ROS positive rate of the bacteria increased under the treatment with 0.2 mmol/L of Cr(VI)and 250 nmol/L of F-53B,*** addition,the activities of superoxide dismutase(SOD)and catalase(CAT)were enhanced for scavenging ROS in the bacteria that were exposed to Cr(VI)and *** an antioxidant,rutin was used to repair the toxicity of Cr(VI)and F-53B towards the biofilm formed by the *** rutin was added to the bacteria medium,with either Cr(VI)or F-53B as pollutant,or with the combined pollutants,the extracellular protein content of the bacteria recovered to 0.84,0.94,and 0.85 times that of the control,***,the accumulation of ROS and the activities of SOD and CAT decreased,which indicated that the addition of rutin can alleviate the oxidative stress and promote the antioxidant stress system.

关键词： F-53B Chromium(Cr) Rutin Biofilm Toxic effect Repair

Entanglement of Para-Bose Entangled Coherent States and Probabilistic Teleportation

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Communications in Theoretical Physics 2008年第1期49卷 73-76页

作者： qian yi XU Jing-Bo Zhejiang Institute of Modern Physics and Department of Physics Zhejiang University Hangzhou 310027 China

We study the entanglement of the para-Bose entangled coherent states by adopting the entanglement of formation and propose a scheme of probabilistic teleportation via para-Bose entangled coherent states. It is found that the mean fidelity of the scheme increases with the decrease of the para-Bose parameter ho in the case of non-maximally entangled para-Bose entangled coherent states.

关键词： probabilistic teleportation entanglement para-Bose entangled coherent states

Explicit formula for the Liutex vector and physical meaning of vorticity based on the Liutex-Shear decomposition

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Journal of Hydrodynamics 2019年第3期31卷 464-474页

作者： yi-qian Wang yi-sheng Gao Jian-ming Liu Chaoqun Liu School of Aerospace Engineering Tsinghua University Beijing 100084 China Department of Mathematics University of Texas at Arlington Arlington 76019 Texas USA School of Mathematics and Statistics Jiangsu Normal University Xuzhou 221116 China

In the present study, the physical meaning of vorticity is revisited based on the Liutex-Shear (RS) decomposition proposed by Liu et al. in the framework of Liutex (previously called Rortex), a vortex vector field with information of both rotation axis and swirling strength (Liu et al. 2018). It is demonstrated that the vorticity in the direction of rotational axis is twice the spatial mean angular velocity in the small neighborhood around the considered point while the imaginary part of the complex eigenvalue (2c.) of the velocity gradient tensor (if exist) is the pseudo-time average angular velocity of a trajectory moving circularly or spirally around the axis. In addition, an explicit expression of the Liutex vector in terms of the eigenvalues and eigenvectors of velocity gradient is obtained for the first time from above understanding, which can further, though mildly, accelerate the calculation and give more physical comprehension of the Liutex vector.

关键词： Vorticity Liutex Liutex-Shear(RS)decomposition explicit formula of Liutex