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Non-equilibrium concentration profile formulas of suspended sediment and their preliminary applications

International Journal of Sediment Research 2022年第4期37卷 505-513页

作者： Zipu Ma Qingchao Guo Jianzhao Guan maohua le State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Yellow River Institute of Hydraulic Research Yellow River Conservancy Commission of the Ministry of Water Resources

The vertical concentration profiles in non-equilibrium sediment transport processes generally deviate from the equilibrium concentration distribution of suspended sediment. The non-equilibrium concentration profile formulas currently available are those of Han and Brown, respectively. However, the complexity of these formulas limits their use in practical calculations. To improve the usefulness of these formulas, the unknown parameters in Han’s formula are reduced from three to two, and the three different forms of Brown’s formula are transformed into one. These formulas then are proved to be essentially the same to some extent, and only different in the expression form of the exponent. Han’s formula then is improved, based on which the theoretical calculation methods and distribution characteristics of non-equilibrium profiles are presented. Han’s and Brown’s formulas are verified qualitatively and quantitatively. Finally, these formulas are applied in the investigation of the characteristics of certain physical quantities, such as the recovery factor of sediment concentration, near-bottom sediment flux, and the non-equilibrium P eclet number in the non-equilibrium sediment transport process. These results clearly reveal that the magnitude of these physical quantities decreases in the erosion process and increases in the deposition process. The results also show that the formulas are largely applicable for the non-equilibrium sediment transport conditions.

关键词： Suspended sediment Vertical concentration profiles Non-equilibrium sediment conditions Non-saturation parameter Péclet number

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On the Diophantine Equation x^2-kxy+y^2+lx=0

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Chinese Annals of Mathematics,Series B 2013年第5期34卷 715-718页

作者： Yongzhong HU maohua le Department of Mathematics Foshan University Institute of Mathematics Zhanjiang Normal College

let l be a given nonzero integer. The authors give an explicit characterization of the positive integer k that makes the Diophantine equation x2 - kxy ＋ y2 ＋ 1x = 0 have infinitely many positive integer solutions （... 详细信息

关键词： Quadratic Diophantine equation Solvability Counting solutions

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CMAES-WFD:Adversarial Website Fingerprinting Defense Based on Covariance Matrix Adaptation Evolution Strategy

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Computers, Materials & Continua 2024年第5期79卷 2253-2276页

作者： Di Wang Yuefei Zhu Jinlong Fei maohua Guo School of Cyberspace Security Information Engineering UniversityZhengzhou450000China

Website fingerprinting,also known asWF,is a traffic analysis attack that enables local eavesdroppers to infer a user’s browsing destination,even when using the Tor anonymity *** advanced attacks based on deep neural network(DNN)can performfeature engineering and attain accuracy rates of over 98%,research has demonstrated thatDNNis vulnerable to adversarial *** a result,many researchers have explored using adversarial samples as a defense mechanism against DNN-based WF attacks and have achieved considerable ***,these methods suffer from high bandwidth overhead or require access to the target model,which is *** paper proposes CMAES-WFD,a black-box WF defense based on adversarial *** process of generating adversarial examples is transformed into a constrained optimization problem solved by utilizing the Covariance Matrix Adaptation Evolution Strategy(CMAES)optimization *** are injected into the local parts of the original traffic to control bandwidth *** to the experiment results,CMAES-WFD was able to significantly decrease the accuracy of Deep Fingerprinting(DF)and VarCnn to below 8.3%and the bandwidth overhead to a maximum of only 14.6%and 20.5%,***,for Automated Website Fingerprinting(AWF)with simple structure,CMAES-WFD reduced the classification accuracy to only 6.7%and the bandwidth overhead to less than 7.4%.Moreover,it was demonstrated that CMAES-WFD was robust against adversarial training to a certain extent.

关键词： Traffic analysis deep neural network adversarial sample Tor website fingerprinting

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RESEARCH ANNOUNCEMENTSOn the Simultaneous Pell Equations x2-D1y2=δ and z2 - D2y2 =δ

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数学进展 2001年第1期30卷 87-88页

作者：乐茂华湛江师范学院广东湛江 524048

　　let , , be the sets of all integers, positive integers and rational numbers, *** D1, D2 be distinct positive integers, and let δ∈-1, 1. The simultaneous Pell equations x2-D1y2=δ, z2-D2y2=δ, x,y,z∈, y≠0 1 arise in connection with a variety of classical problems on number theory and arithmetic algebraic geometry. As has been noted by K. One［1］, the solutions (x,y,z) of (1) imply the existence of rational points of infinite order on the elliptic curve E=Eδ: Y2=X(X+δD1)(X+δD2). let p,q be twin primes with

关键词： DI RESEARCH ANNOUNCEMENTSOn the Simultaneous Pell Equations x~2-D and z~2

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Small-scale fire tests in the underwater tunnel section model with new sidewall smoke extraction

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Deep Underground Science and Engineering 2024年第2期3卷 247-254页

作者： Shunyu Yue Ruifeng Miao Huihang Cheng maohua Zhong Xiujun Yang Department of Engineering Physics Institute of Public Safety ResearchTsinghua UniversityBeijingChina Shanxi Province Expressway Group Limited Liability Company Shanxi Expressway Group Shuoshen Co. LtdShuozhouChina Research Institute of Highway Ministry of Transport RIOH Transport ConsultantsLtdBeijingChina

The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea *** solve the smoke exhaust problem of a super large cross-section subsea tunnel,the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust *** order to evaluate the potential fire hazards of this type of tunnel,a 1:30 tunnel model was established and 140 smallscale experiments on underwater tunnel fires were *** changing the fire power,fire location,and fan operation mode,different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were *** this basis,the optimal smoke control strategy was proposed for different fire *** research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics,significantly improve smoke exhaust efficiency,and increase available evacuation time,thus further enhancing the fire safety of super large cross-section subsea tunnels.

关键词： sidewall smoke extraction system small‐scale fire tests smoke control

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Multiparameter collaborative optimization of the vibrating screen based on the behavior of oil sunflower seed penetrating screen holes

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 49-58页

作者： Wenbo Wei Jianchang Li Jianjun Hao maohua Xiao Huiju Zhang College of Mechanical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001HebeiChina College of Engineering Nanjing Agricultural UniversityNanjing 210032China The Higher Educational Key Laboratory for Flexible Manufacturing Equipment Integration of Fujian Province Xiamen Institute of TechnologyXiamen 361000FujianChina

The behavior of oil sunflower seeds penetrating screen holes is an important factor that affects the screening performance of oil sunflower *** this study,a double-deck reverse-motion vibrating screening device for oil sunflower seed screening was *** force condition and motion law of the oil sunflower seeds on the screen surface were *** study compared the effect of particle filling amount of discrete element model of oil sunflower seeds on the simulation *** screening process was numerically simulated using the coupled Discrete Element Method and Multibody Dynamics(DEM-MBD)technique with the screening percentage of oil sunflower seeds as the *** influence of the operating parameters of the vibrating screen on the screening effect was analyzed using a multiparameter collaborative optimization *** results of this study can provide a reference for the numerical simulation of crop screening behavior and the development of screening devices.

关键词： oil sunflower seeds screening analysis DEM-MBD discrete element method response surface analysis

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RpUGT344J7 is involved in the reproduction switch of Rhopalosiphum padi with holocyclic life cycle

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Insect Science 2024年第4期31卷 1073-1089页

作者： Suji Wang Wenjie Huang Mengtian Li Ni Wang Xi Liu maohua Chen Xiong Peng State Key Laboratory of Crop Stress Biology for Arid Areas Key Laboratory of Plant Protection Resources and Pest Management of Ministry of EducationKey Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture and Rural AffairsCollege of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi ProvinceChina

Many aphid species exhibit both cyclical parthenogenesis(CP)and the obligate parthenogenesis(OP)life history,which are genetically *** CP aphid lineages,the parthenogenetic individuals can switch from asexual to sexual reproduction quickly in response to environmental factors such as changes in photoperiod and ***,the OP aphid lineages do not undergo sexual reproduction under any *** far,mechanisms underlying the reproduction switch in CP aphids have not been fully *** padi,a serious worldwide insect pest of wheat,has both CP and OP *** diphosphate-glycosyltransferases(UGTs)are enzymes that participate in the metabolic detoxification of ***,we identified 43 RpUGT genes from *** genome and transcriptome sequences,and found that:(1)the UGT content of the CP lineage was significantly higher than that in the OP lineage at the key time points when CP lineage mainly produce virginoparae,gynoparae,and males under inducing condition,while there were no significant difference under normal conditions;(2)RpUGT344J7 gene was highly expressed during the time points when CP lineages produce gynopara and males;(3)the critical time points for CP lineages to produce virginoparaee,gynoparae,and males were affected when the CP lineages were injected with dsRpUGT344J7;(4)the knockdown of RpUGT344J7 caused a significant reduction in the total number of virginoparae,gynoparae,and males in the offspring under inducing *** findings contribute to our understanding of the molecular mechanisms underlying the quick shift from asexual to sexual reproduction in aphid species.

关键词： bird cherry-oat aphid cyclical parthenogenesis obligate parthenogenesis reproduction switch uridine diphosphate-glycosyltransferases(UGTs)

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