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DDoS Attack Autonomous Detection Model Based on Multi-Strategy Integrate Zebra Optimization Algorithm

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Computers, Materials & Continua 2025年第1期82卷 645-674页

作者： Chunhui Li Xiaoying Wang qingjie Zhang Jiaye Liang Aijing Zhang School of Information Engineering Institute of Disaster PreventionLangfang065201China Langfang Key Laboratory of Network Emergency Protection and Network Security Langfang065201China

Previous studies have shown that deep learning is very effective in detecting known ***,when facing unknown attacks,models such as Deep Neural Networks(DNN)combined with Long Short-Term Memory(LSTM),Convolutional Neural Networks(CNN)combined with LSTM,and so on are built by simple stacking,which has the problems of feature loss,low efficiency,and low ***,this paper proposes an autonomous detectionmodel for Distributed Denial of Service attacks,Multi-Scale Convolutional Neural Network-Bidirectional Gated Recurrent Units-Single Headed Attention(MSCNN-BiGRU-SHA),which is based on a Multistrategy Integrated Zebra Optimization Algorithm(MI-ZOA).The model undergoes training and testing with the CICDDoS2019 dataset,and its performance is evaluated on a new GINKS2023 *** hyperparameters for Conv_filter and GRU_unit are optimized using the Multi-strategy Integrated Zebra Optimization Algorithm(MIZOA).The experimental results show that the test accuracy of the MSCNN-BiGRU-SHA model based on the MIZOA proposed in this paper is as high as 0.9971 in the CICDDoS 2019 *** evaluation accuracy of the new dataset GINKS2023 created in this paper is *** to the MSCNN-BiGRU-SHA model based on the Zebra Optimization Algorithm(ZOA),the detection accuracy on the GINKS2023 dataset has improved by 5.81%,precisionhas increasedby 1.35%,the recallhas improvedby 9%,and theF1scorehas increasedby 5.55%.Compared to the MSCNN-BiGRU-SHA models developed using Grid Search,Random Search,and Bayesian Optimization,the MSCNN-BiGRU-SHA model optimized with the MI-ZOA exhibits better performance in terms of accuracy,precision,recall,and F1 score.

关键词： Distributed denial of service attack intrusion detection deep learning zebra optimization algorithm multi-strategy integrated zebra optimization algorithm

The effect of the Ce content on the oxidative dehydrogenation of propane over CrOy-CeO2/γ-Al2O3 catalysts

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3035-3043页

作者： Cheng Zuo Man Wu qingjie Guo Key Laboratory of Clean Chemical Processing of Shandong Province College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China

A series of CrOy(17.5 wt%)-CeO2(X wt%)/γ-Al2O3 catalysts(X=0,0.5,2,5,8)with various Ce contentswere prepared by a wetness impregnation method and were applied to the dehydrogenation of propane to propylene at 550℃ and 0.1 *** prepared catalysts were characterized by BET,H2-TPR,O2-TPD,XPS,XRD,SEM-EDS and Raman *** the prepared catalysts,the 17.5Cr-2Ce/Al catalyst with the largest amount of lattice oxygen exhibited the best catalytic performance for the dehydrogenation of propane to propylene with lattice *** decreased presence of oxygen defects and reducibility were the factors responsible for the improved dehydrogenation activity of the *** CeO2 layer could inhibit the evolution of lattice oxygen(O2^−)to electrophilic oxygen species(O2^−),and the oxygen defects on the catalyst surfacewere *** inhibited lattice oxygen evolution prevented the deep oxidation of propane or propylene,the average COx selectivity decreased from 24.41%(17.5Cr/Al)to 5.71%(17.5Cr-2Ce/Al),and the average propylene selectivity increased from 60.15%(17.5Cr/Al)to 85.05%(17.5Cr-2Ce/Al).

关键词： Oxidation Selectivity Propane Propylene Fluidized-bed Oxygen carrier

Experimental study of a highway bridge with shape memory alloy restrainers focusing on the mitigation of unseating and pounding

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Earthquake Engineering and Engineering Vibration 2012年第2期11卷 195-204页

作者： Guo, Anxin Zhao, qingjie Li, Hui School of Civil Engineering Harbin Institute of Technology Harbin 150090 China School of Civil Engineering the 2nd Campus Harbin Institute of Technology P.O. Box 2537 Harbin 150090 China

This paper presents an experimental study to investigate the performance of shape memory alloy(SMA) restrainers for mitigating the pounding and unseating of highway bridges when subjected to seismic *** property tests of the SMA wire used in the restrainers are conducted first to understand the pseudo-elastic characteristics of the ***,a series of shaking table tests are carried out on a highway bridge *** structural responses of the highway bridge model equipped with SMA restrainers,installed in the form of deck-deck and deck-pile connections,are analyzed and compared with the uncontrolled *** test results of this study indicate that the SMA restrainers are not only effective in preventing unseating but also in suppressing the seismic-induced pounding of the highway bridge model used in this study.

关键词： shape memory alloy restrainer unseating pounding highway bridge

Isolation performances and optimization of triple quasi-zero stiffness isolators

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 124-141页

作者： Yuntian Zhang Guangnan Zhu qingjie Cao School of Astronautics Harbin Institute of TechnologyHarbin 150001China

In this paper,triple quasi-zero stiffness(QZS)passive vibration isolators whose restoring force curve has a three-stage softening effect are ***-coupled SD oscillators with three independent geometrical parameters are used as negative stiffness mechanisms to achieve QZS characteristics at the origin and symmetrical positions on both sides of the *** performances of different triple QZS isolators are analyzed to show influences of the selection of QZS regions away from the origin on the range of isolation *** optimizations of system parameters are carried out to get a larger range of small restoring force regions and small stiffness *** performances of two triple QZS isolators are discussed to show the influence of different Pareto optimization solutions through the comparisons with single and double QZS *** showed that triple QZS isolators have both the advantages of single and double QZS isolators which results in better isolation performances under both small and large excitation *** improvement in isolation performances for triple QZS isolators is found with the decrease in average stiffness due to the appearance of two symmetrical QZS regions away from the *** displacements of QZS regions away from the origin result in better isolation performances when excitation amplitude is large,and triple QZS characteristics are similar to double QZS isolators at this *** restoring forces of QZS regions away from the origin lead to better isolation performances when excitation amplitude is small,and triple QZS characteristics are similar to single QZS isolators at this *** with the decrease in average stiffness,the improvement of isolation performances shows a hysteresis phenomenon due to the difference between static and dynamic characteristics.

关键词： triple quasi-zero stiffness vibration isolation Pareto optimization force transmissibility geometrical nonlinear

Splitting touching cells based on concave-point and improved watershed algorithms

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Frontiers of Computer Science 2014年第1期8卷 156-162页

作者： Hong SONG qingjie ZHAO Yinghong LIU School of Software Beijing Institute of Technology Beijing 100081 China School of Computer Science Beijing Institute of Technology Beijing 100081 China

Splitting touching cells is important for medi- cal image processing and analysis system. In this paper, a novel strategy is proposed to separate ellipse-like or circle- like touching cells in which different algorithms are used ac- cording to the concave-point cases of touching domains. In the strategy, a concave-point extraction and contour segmen- tation methods for cells in series and in parallel are used for the images with distinct concave points, and an improved watershed algorithm with multi-scale gradient and distance transformation is adopted for the images with un-distinct or complex concave points. In order to visualize each whole cell, ellipse fitting is used to process the segments. Experimental results show that, for the cell images with distinct concave points, both of the two algorithms can achieve good separat- ing results, but the concave-point based algorithm is more ef- ficient. However, for the cell images with unobvious or com- plex concave points, the improved watershed based algorithm can give satisfying segmenting results.

关键词： touching cells splitting concave points water-shed ellipse fitting

Recovery of V_2O_5 from Bayer liquor by ion exchange

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Rare Metals 2010年第2期29卷 115-120页

作者： ZHAO Zhuo LI Xiaobin ZHAO qingjie School of Metallurgical Science andEngineering Central South University Changsha 410083 China Zhengzhou Research Institute ofChalco Ltd Zhengzhou 450041 China

A new technology was developed to recover V2O5 from Bayer spent liquor by ion *** experimental results show that in the conditions of 105℃ and 0.20-0.25 mass ratios between CaO in lime and Al2O3 in spent liquor, the precipitation rate of vanadium in Bayer liquor is more than 85%.The vanadium-bearing precipitation is leached by NaHCO3 *** leaching rate of vanadium can reach 85% in the conditions of 95℃, 40 g·L-1 of NaHCO3 concentration, and ventilating of *** 201 × 7 type of resin has good adsorption effect on vanadium in the leaching *** adsorption rate is more than 94% with the flow rate of 0.09 mL·min-1·g-1 of leaching solution and the temperature of 40-50℃.By using 3 mol·L-1 of NaOH to desorb the saturated resin after adsorption at 40-50℃, a solution with more than 5 g·L-1 of V2O5 can be *** roasting ammonium metavanadate that precipitates from the desorption solution when NH4Cl is added at the temperature of 500-550℃ for 2 h, V2O5 with more than 99% of purity is obtained.

关键词： abstraction metallurgy V2O5 ion exchange Bayer process spent liquor

Oxide-supported Aun（SR）m nanoclusters for CO oxidation

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催化学报 2015年第2期36卷 135-138页

作者： Weili Li 葛庆杰 qingjie Ge Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

Supported Au nanoparticles have been extensively investigated in heterogeneous catalysis since the seminal work of Haruta's research group, in part because of their high activity in some reactions, especially CO oxidation. Although many studies have been performed, two problems still remain: aggregation of Au nanoparticles and their catalytic reaction mechanism. Many strategies have been developed to increase Au nanoparticle stability, such as modification of metal nanoparticle composition, metal-support interfaces, and support nanostructures. However, Au particles prepared by the deposition-precipitation method are usually larger than 2 nm. Au nanoparticles smaller than 2 nm easily aggregate, and how to stabilize them is an interesting topic. In addition, many studies on the reaction mechanism catalyzed by supported Au nanoparticles have been performed, but the conclusions are not in agreement. This is mainly because of the heterogeneous distribution of the active metal in the catalysts, which are usually prepared by the traditional deposition-precipitation method.

关键词：金纳米粒子 CO氧化纳米团簇负载氧化物金属纳米粒子 SR 多相催化

In situ carbon nanotube synthesis by the reduction of NiO/γ-Al_2O_3 catalyst in methane

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Journal of Natural Gas Chemistry 2010年第6期19卷 617-621页

作者： Dongyan Xu Haizhen Wang qingjie Guo College of Chemical Engineering Qingdao University of Science and Technology Qingdao 266042 Shandong China

The synthesis of carbon nanotubes （CNTs） via chemical vapour deposition of methane on NiO/γ-Al2O3 catalyst has been *** reduction behavior of NiO/γ-Al2O3 by methane was studied using thermogravimetric （TG） and X-ray diffraction （XRD） *** was found that the NiO supported on γ-Al2O3,was reduced to Ni0 in methane atmosphere in the temperature range of 710-770℃.The catalytic activity of NiO/γ-Al2O3 for CNTs synthesis by in situ chemical vapour deposition of methane during the reduction was also *** electron microscopy （SEM） and transmission electron microscopy （TEM） were used to observe the CNTs produced at various reduction *** results indicated that the reduction temperature exhibits obvious influence on the morphology and the yield of *** with the diameter of about 20 nm were obtained at reduction temperature of 750℃,and higher reduction temperature （such as 800 and 850℃） led to an increase in CNTs diameter and a decrease in CNTs yield.

关键词： chemical vapour deposition carbon nanotubes NiO/γ-Al2O3 catalyst reduction temperature

Experimental definition and its significance on the minimum safe distance of blown sand between the proposed Qinghai-Tibet Expressway and the existing Qinghai-Tibet Railway

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Science China(Technological Sciences) 2020年第12期63卷 2664-2676页

作者： XIE ShengBo QU JianJun HAN qingjie PANG YingJun Key Laboratory of Desert and Desertification Dunhuang Gobi and Desert Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institute of Desertification Studies Chinese Academy of ForestryBeijing 100091China

The Qinghai-Tibet Expressway is a major strategic project planned by China that will be built along the Qinghai-Tibet Engineering Corridor. At present,important traffic line projects,such as the Qinghai-Tibet Railway,have been built within this narrow corridor,particularly at the blown sand sections. How to ensure that the wind speed and its flow field between the new expressway and existing railway subgrades are not affected by each other is a priority to prevent breaking the dynamic balance of the blown sand movement of the existing subgrade,thereby avoiding aggravating or inducing new blown sand hazards and ensure the safe operation of the existing Qinghai-Tibet Railway. Therefore,defining the minimum distance of the wind speed and its flow field,which are not affected by each other,between the subgrades become a scientific problem that should be solved immediately to implement the construction of the Qinghai-Tibet Expressway. For this purpose,the minimum safe distance between the subgrades of the Qinghai-Tibet Expressway and Qinghai-Tibet Railway was investigated from the perspective of blown sand by making subgrade models for conducting wind tunnel experiments and combining the observation data of the local field. Results indicated that the minimum safe distance between the two subgrades is 45–50 times the subgrade height when the Qinghai-Tibet Expressway is located at the downwind direction of the Qinghai-Tibet Railway,and 50 times the subgrade height when the former is located at the upwind direction of the latter. These results have guiding significance for the route selection,survey,and design of the Qinghai-Tibet Expressway at the blown sand sections and for the traffic line projects in other similar sandy regions.

关键词： Qinghai-Tibet Expressway Qinghai-Tibet Railway wind speed wind flow field safety distance